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https://zbmath.org/authors/?q=ai%3Aplonka.gerlind
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zbMATH — the first resource for mathematics
Plonka, Gerlind
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Author ID: plonka.gerlind Published as: Plonka, G.; Plonka, Gerlind External Links: MGP · Wikidata · GND
Documents Indexed: 75 Publications since 1992, including 3 Books Reviewing Activity: 184 Reviews
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Co-Authors
17 single-authored 12 Tasche, Manfred 5 Roşca, Daniela 4 Berg, Lothar 4 Steidl, Gabriele 3 Iske, Armin 3 Ma, Jianwei 3 Tenorth, Stefanie 3 Wannenwetsch, Katrin 2 Beinert, Robert 2 Bittens, Sina Vanessa 2 Heinen, Dennis 2 Peter, Thomas 2 Stampfer, Kilian 2 Strela, Vasily 2 Wischerhoff, Marius 1 Budinich, Renato 1 Chen, Dirong 1 Cohen, Albert 1 Cuyt, Annie A. M. 1 Daubechies, Ingrid Chantal 1 Gonska, Heinz Herbert 1 Guillemard, Mijail 1 Hasannasab, Marzieh 1 Hertrich, Johannes 1 Hoffmann, Sebastian 1 Jetter, Kurt 1 Keller, Ingeborg 1 Krause-Solberg, Sara 1 Krommweh, Jens 1 Kutyniok, Gitta 1 Lee, Wen-shin 1 Liu, Lina 1 Loock, Stefan 1 Neumayer, Sebastian 1 Pototskaia, Vlada 1 Potts, Daniel 1 Ron, Amos 1 Schumacher, Hagen 1 Selig, Kathi K. 1 Setzer, Simon 1 Weickert, Joachim 1 Zhang, Ran 1 Zheng, Yi 1 Zhou, Dingxuan
all top 5
Serials
5 Results in Mathematics 5 Numerical Algorithms 5 Applied and Computational Harmonic Analysis 5 Advances in Computational Mathematics 5 International Journal of Wavelets, Multiresolution and Information Processing 4 Journal of Approximation Theory 4 Linear Algebra and its Applications 4 The Journal of Fourier Analysis and Applications 3 Inverse Problems 3 Journal of Computational and Applied Mathematics 3 Rostocker Mathematisches Kolloquium 3 Constructive Approximation 2 Mathematics of Computation 2 GAMM-Mitteilungen 1 Numerische Mathematik 1 Journal of Symbolic Computation 1 SIAM Journal on Mathematical Analysis 1 IEEE Transactions on Image Processing 1 Journal of Applied Mathematics and Computing 1 Multiscale Modeling & Simulation 1 Analysis and Applications (Singapore) 1 Mathematical Geosciences 1 Applied and Numerical Harmonic Analysis
all top 5
Fields
43 Numerical analysis (65-XX) 38 Harmonic analysis on Euclidean spaces (42-XX) 25 Information and communication theory, circuits (94-XX) 24 Approximations and expansions (41-XX) 6 Linear and multilinear algebra; matrix theory (15-XX) 6 Computer science (68-XX) 5 Difference and functional equations (39-XX) 3 Functional analysis (46-XX) 3 Statistics (62-XX) 3 Geophysics (86-XX) 2 Partial differential equations (35-XX) 1 General and overarching topics; collections (00-XX) 1 Special functions (33-XX) 1 Operator theory (47-XX) 1 Calculus of variations and optimal control; optimization (49-XX) 1 Manifolds and cell complexes (57-XX) 1 Astronomy and astrophysics (85-XX) 1 Operations research, mathematical programming (90-XX)
Citations contained in zbMATH
60 Publications have been cited 440 times in 291 Documents Cited by Year
Regularity of refinable function vectors. Zbl 0914.42025
Cohen, Albert; Daubechies, Ingrid; Plonka, Gerlind
1997
Approximation order provided by refinable function vectors. Zbl 0870.41015
Plonka, G.
1997
Construction of multiscaling functions with approximation and symmetry. Zbl 0928.42017
Plonka, G.; Strela, V.
1998
A generalized Prony method for reconstruction of sparse sums of eigenfunctions of linear operators. Zbl 1276.47093
Peter, Thomas; Plonka, Gerlind
2013
Prony methods for recovery of structured functions. Zbl 1311.65012
Plonka, Gerlind; Tasche, Manfred
2014
A survey on $$L_2$$-approximation orders from shift-invariant spaces. Zbl 1039.42033
Jetter, K.; Plonka, G.
2001
From wavelets to multiwavelets. Zbl 0905.65138
Plonka, Gerlind; Strela, Vasily
1998
Fast and numerically stable algorithms for discrete cosine transforms. Zbl 1072.65171
Plonka, Gerlind; Tasche, Manfred
2005
On the computation of periodic spline wavelets. Zbl 0810.42018
Plonka, Gerlind; Tasche, Manfred
1995
A unified approach to periodic wavelets. Zbl 0874.42026
Plonka, Gerlind; Tasche, Manfred
1994
How many Fourier samples are needed for real function reconstruction? Zbl 1296.42001
Plonka, Gerlind; Wischerhoff, Marius
2013
Ambiguities in one-dimensional discrete phase retrieval from Fourier magnitudes. Zbl 1388.42004
Beinert, Robert; Plonka, Gerlind
2015
Some notes on two-scale difference equations. Zbl 0978.39004
Berg, Lothar; Plonka, Gerlind
2000
On the construction of wavelets on a bounded interval. Zbl 0838.65140
Plonka, Gerlind; Selig, Kathi; Tasche, Manfred
1995
Enforcing uniqueness in one-dimensional phase retrieval by additional signal information in time domain. Zbl 1394.42001
Beinert, Robert; Plonka, Gerlind
2018
Spectral properties of two-slanted matrices. Zbl 0931.15004
Berg, Lothar; Plonka, Gerlind
1999
A deterministic sparse FFT algorithm for vectors with small support. Zbl 1341.65056
Plonka, Gerlind; Wannenwetsch, Katrin
2016
The easy path wavelet transform: A new adaptive wavelet transform for sparse representation of two-dimensional data. Zbl 1175.65158
Plonka, Gerlind
2009
A multiscale wavelet-inspired scheme for nonlinear diffusion. Zbl 1111.65075
Plonka, Gerlind; Steidl, Gabriele
2006
Convergence of cascade algorithms in Sobolev spaces for perturbed refinement masks. Zbl 1017.42029
Chen, Di-Rong; Plonka, Gerlind
2002
Representation of sparse Legendre expansions. Zbl 1261.65016
Peter, Thomas; Plonka, Gerlind; Roşca, Daniela
2013
Uniform spherical grids via equal area projection from the cube to the sphere. Zbl 1231.65044
Roşca, Daniela; Plonka, Gerlind
2011
Curvelet-wavelet regularized split Bregman iteration for compressed sensing. Zbl 1208.94017
Plonka, Gerlind; Ma, Jianwei
2011
Compactly supported solutions of two-scale difference equations. Zbl 0935.39003
Berg, Lothar; Plonka, Gerlind
1998
Two-scale symbol and autocorrelation symbol for B-splines with multiple knots. Zbl 0828.41007
Plonka, Gerlind
1995
Periodic spline interpolation with shifted nodes. Zbl 0803.41003
Plonka, Gerlind
1994
A sparse fast Fourier algorithm for real non-negative vectors. Zbl 1366.65118
Plonka, Gerlind; Wannenwetsch, Katrin
2017
Directional Haar wavelet frames on triangles. Zbl 1177.42031
Krommweh, Jens; Plonka, Gerlind
2009
Factorization of refinement masks of function vectors. Zbl 0927.42028
Plonka, Gerlind
1995
Numerical Fourier analysis. Zbl 1412.65001
Plonka, Gerlind; Potts, Daniel; Steidl, Gabriele; Tasche, Manfred
2018
Deterministic sparse FFT for $$M$$-sparse vectors. Zbl 06871983
Plonka, Gerlind; Wannenwetsch, Katrin; Cuyt, Annie; Lee, Wen-Shin
2018
Reconstruction of polygonal shapes from sparse Fourier samples. Zbl 1362.94012
Wischerhoff, Marius; Plonka, Gerlind
2016
Phase retrieval for Fresnel measurements using a shearlet sparsity constraint. Zbl 1293.42034
Loock, Stefan; Plonka, Gerlind
2014
Optimally sparse image representation by the easy path wavelet transform. Zbl 1251.42012
Plonka, Gerlind; Tenorth, Stefanie; Iske, Armin
2012
A new hybrid method for image approximation using the easy path wavelet transform. Zbl 1372.94210
Plonka, Gerlind; Tenorth, Stefanie; Roşca, Daniela
2011
Easy path wavelet transform on triangulations of the sphere. Zbl 1198.42052
Plonka, Gerlind; Roşca, Daniela
2010
A new factorization technique of the matrix mask of univariate refinable functions. Zbl 0982.65150
Plonka, Gerlind; Ron, Amos
2001
Spline wavelets with higher defect. Zbl 0815.65012
Plonka, G.
1994
Efficient algorithms for periodic Hermite spline interpolation. Zbl 0769.65005
Plonka, G.; Tasche, M.
1992
Computation of adaptive Fourier series by sparse approximation of exponential sums. Zbl 1420.42002
2019
Optimal approximation with exponential sums by a maximum likelihood modification of Prony’s method. Zbl 1415.65095
Zhang, Ran; Plonka, Gerlind
2019
Optimal representation of piecewise Hölder smooth bivariate functions by the easy path wavelet transform. Zbl 1281.42040
Plonka, Gerlind; Iske, Armin; Tenorth, Stefanie
2013
An area preserving projection from the regular octahedron to the sphere. Zbl 1260.86015
Roşca, Daniela; Plonka, Gerlind
2012
Wavelet shrinkage on paths for denoising of scattered data. Zbl 1253.42034
Heinen, Dennis; Plonka, Gerlind
2012
Integer DCT-II by lifting steps. Zbl 1036.65118
Plonka, Gerlind; Tasche, Manfred
2003
Invertible integer DCT algorithms. Zbl 1030.65144
Plonka, Gerlind; Tasche, Manfred
2003
Necessary and sufficient conditions for orthonormality of scaling vectors. Zbl 0903.42017
Plonka, Gerlind
1997
Generalized spline wavelets. Zbl 0848.41009
Plonka, G.
1996
Approximation properties of multi-scaling functions: A Fourier approach. Zbl 0852.42021
Plonka, Gerlind
1995
Real sparse fast DCT for vectors with short support. Zbl 07125930
Bittens, Sina; Plonka, Gerlind
2019
Sparse fast DCT for vectors with one-block support. Zbl 07107362
Bittens, Sina; Plonka, Gerlind
2019
Reconstruction of stationary and non-stationary signals by the generalized Prony method. Zbl 1422.94015
Plonka, Gerlind; Stampfer, Kilian; Keller, Ingeborg
2019
Seismic data interpolation and denoising by learning a tensor tight frame. Zbl 1411.86004
Liu, Lina; Plonka, Gerlind; Ma, Jianwei
2017
Pseudo-inverses of difference matrices and their application to sparse signal approximation. Zbl 1338.15013
Plonka, Gerlind; Hoffmann, Sebastian; Weickert, Joachim
2016
Numerical stability of fast trigonometric and orthogonal wavelet transforms. Zbl 1060.65139
Plonka, Gerlind; Tasche, Manfred
2004
A global method for invertible integer DCT and integer wavelet algorithms. Zbl 1053.65103
Plonka, Gerlind
2004
Properties of locally linearly independent refinable function vectors. Zbl 1031.41020
Plonka, G.; Zhou, D.-X.
2003
On stability of scaling vectors. Zbl 0939.65148
Plonka, Gerlind
1997
Cardinal Hermite spline interpolation with shifted nodes. Zbl 0819.65008
Plonka, Gerlind; Tasche, Manfred
1994
An efficient algorithm for periodic Hermite spline interpolation with shifted nodes. Zbl 0803.65009
Plonka, Gerlind
1993
Computation of adaptive Fourier series by sparse approximation of exponential sums. Zbl 1420.42002
2019
Optimal approximation with exponential sums by a maximum likelihood modification of Prony’s method. Zbl 1415.65095
Zhang, Ran; Plonka, Gerlind
2019
Real sparse fast DCT for vectors with short support. Zbl 07125930
Bittens, Sina; Plonka, Gerlind
2019
Sparse fast DCT for vectors with one-block support. Zbl 07107362
Bittens, Sina; Plonka, Gerlind
2019
Reconstruction of stationary and non-stationary signals by the generalized Prony method. Zbl 1422.94015
Plonka, Gerlind; Stampfer, Kilian; Keller, Ingeborg
2019
Enforcing uniqueness in one-dimensional phase retrieval by additional signal information in time domain. Zbl 1394.42001
Beinert, Robert; Plonka, Gerlind
2018
Numerical Fourier analysis. Zbl 1412.65001
Plonka, Gerlind; Potts, Daniel; Steidl, Gabriele; Tasche, Manfred
2018
Deterministic sparse FFT for $$M$$-sparse vectors. Zbl 06871983
Plonka, Gerlind; Wannenwetsch, Katrin; Cuyt, Annie; Lee, Wen-Shin
2018
A sparse fast Fourier algorithm for real non-negative vectors. Zbl 1366.65118
Plonka, Gerlind; Wannenwetsch, Katrin
2017
Seismic data interpolation and denoising by learning a tensor tight frame. Zbl 1411.86004
Liu, Lina; Plonka, Gerlind; Ma, Jianwei
2017
A deterministic sparse FFT algorithm for vectors with small support. Zbl 1341.65056
Plonka, Gerlind; Wannenwetsch, Katrin
2016
Reconstruction of polygonal shapes from sparse Fourier samples. Zbl 1362.94012
Wischerhoff, Marius; Plonka, Gerlind
2016
Pseudo-inverses of difference matrices and their application to sparse signal approximation. Zbl 1338.15013
Plonka, Gerlind; Hoffmann, Sebastian; Weickert, Joachim
2016
Ambiguities in one-dimensional discrete phase retrieval from Fourier magnitudes. Zbl 1388.42004
Beinert, Robert; Plonka, Gerlind
2015
Prony methods for recovery of structured functions. Zbl 1311.65012
Plonka, Gerlind; Tasche, Manfred
2014
Phase retrieval for Fresnel measurements using a shearlet sparsity constraint. Zbl 1293.42034
Loock, Stefan; Plonka, Gerlind
2014
A generalized Prony method for reconstruction of sparse sums of eigenfunctions of linear operators. Zbl 1276.47093
Peter, Thomas; Plonka, Gerlind
2013
How many Fourier samples are needed for real function reconstruction? Zbl 1296.42001
Plonka, Gerlind; Wischerhoff, Marius
2013
Representation of sparse Legendre expansions. Zbl 1261.65016
Peter, Thomas; Plonka, Gerlind; Roşca, Daniela
2013
Optimal representation of piecewise Hölder smooth bivariate functions by the easy path wavelet transform. Zbl 1281.42040
Plonka, Gerlind; Iske, Armin; Tenorth, Stefanie
2013
Optimally sparse image representation by the easy path wavelet transform. Zbl 1251.42012
Plonka, Gerlind; Tenorth, Stefanie; Iske, Armin
2012
An area preserving projection from the regular octahedron to the sphere. Zbl 1260.86015
Roşca, Daniela; Plonka, Gerlind
2012
Wavelet shrinkage on paths for denoising of scattered data. Zbl 1253.42034
Heinen, Dennis; Plonka, Gerlind
2012
Uniform spherical grids via equal area projection from the cube to the sphere. Zbl 1231.65044
Roşca, Daniela; Plonka, Gerlind
2011
Curvelet-wavelet regularized split Bregman iteration for compressed sensing. Zbl 1208.94017
Plonka, Gerlind; Ma, Jianwei
2011
A new hybrid method for image approximation using the easy path wavelet transform. Zbl 1372.94210
Plonka, Gerlind; Tenorth, Stefanie; Roşca, Daniela
2011
Easy path wavelet transform on triangulations of the sphere. Zbl 1198.42052
Plonka, Gerlind; Roşca, Daniela
2010
The easy path wavelet transform: A new adaptive wavelet transform for sparse representation of two-dimensional data. Zbl 1175.65158
Plonka, Gerlind
2009
Directional Haar wavelet frames on triangles. Zbl 1177.42031
Krommweh, Jens; Plonka, Gerlind
2009
A multiscale wavelet-inspired scheme for nonlinear diffusion. Zbl 1111.65075
Plonka, Gerlind; Steidl, Gabriele
2006
Fast and numerically stable algorithms for discrete cosine transforms. Zbl 1072.65171
Plonka, Gerlind; Tasche, Manfred
2005
Numerical stability of fast trigonometric and orthogonal wavelet transforms. Zbl 1060.65139
Plonka, Gerlind; Tasche, Manfred
2004
A global method for invertible integer DCT and integer wavelet algorithms. Zbl 1053.65103
Plonka, Gerlind
2004
Integer DCT-II by lifting steps. Zbl 1036.65118
Plonka, Gerlind; Tasche, Manfred
2003
Invertible integer DCT algorithms. Zbl 1030.65144
Plonka, Gerlind; Tasche, Manfred
2003
Properties of locally linearly independent refinable function vectors. Zbl 1031.41020
Plonka, G.; Zhou, D.-X.
2003
Convergence of cascade algorithms in Sobolev spaces for perturbed refinement masks. Zbl 1017.42029
Chen, Di-Rong; Plonka, Gerlind
2002
A survey on $$L_2$$-approximation orders from shift-invariant spaces. Zbl 1039.42033
Jetter, K.; Plonka, G.
2001
A new factorization technique of the matrix mask of univariate refinable functions. Zbl 0982.65150
Plonka, Gerlind; Ron, Amos
2001
Some notes on two-scale difference equations. Zbl 0978.39004
Berg, Lothar; Plonka, Gerlind
2000
Spectral properties of two-slanted matrices. Zbl 0931.15004
Berg, Lothar; Plonka, Gerlind
1999
Construction of multiscaling functions with approximation and symmetry. Zbl 0928.42017
Plonka, G.; Strela, V.
1998
From wavelets to multiwavelets. Zbl 0905.65138
Plonka, Gerlind; Strela, Vasily
1998
Compactly supported solutions of two-scale difference equations. Zbl 0935.39003
Berg, Lothar; Plonka, Gerlind
1998
Regularity of refinable function vectors. Zbl 0914.42025
Cohen, Albert; Daubechies, Ingrid; Plonka, Gerlind
1997
Approximation order provided by refinable function vectors. Zbl 0870.41015
Plonka, G.
1997
Necessary and sufficient conditions for orthonormality of scaling vectors. Zbl 0903.42017
Plonka, Gerlind
1997
On stability of scaling vectors. Zbl 0939.65148
Plonka, Gerlind
1997
Generalized spline wavelets. Zbl 0848.41009
Plonka, G.
1996
On the computation of periodic spline wavelets. Zbl 0810.42018
Plonka, Gerlind; Tasche, Manfred
1995
On the construction of wavelets on a bounded interval. Zbl 0838.65140
Plonka, Gerlind; Selig, Kathi; Tasche, Manfred
1995
Two-scale symbol and autocorrelation symbol for B-splines with multiple knots. Zbl 0828.41007
Plonka, Gerlind
1995
Factorization of refinement masks of function vectors. Zbl 0927.42028
Plonka, Gerlind
1995
Approximation properties of multi-scaling functions: A Fourier approach. Zbl 0852.42021
Plonka, Gerlind
1995
A unified approach to periodic wavelets. Zbl 0874.42026
Plonka, Gerlind; Tasche, Manfred
1994
Periodic spline interpolation with shifted nodes. Zbl 0803.41003
Plonka, Gerlind
1994
Spline wavelets with higher defect. Zbl 0815.65012
Plonka, G.
1994
Cardinal Hermite spline interpolation with shifted nodes. Zbl 0819.65008
Plonka, Gerlind; Tasche, Manfred
1994
An efficient algorithm for periodic Hermite spline interpolation with shifted nodes. Zbl 0803.65009
Plonka, Gerlind
1993
Efficient algorithms for periodic Hermite spline interpolation. Zbl 0769.65005
Plonka, G.; Tasche, M.
1992
all top 5
Cited by 389 Authors
32 Plonka, Gerlind 9 Charina, Maria 9 Conti, Costanza 8 Chen, Dirong 8 Han, Bin 8 Tasche, Manfred 8 Yang, Shouzhi 7 Jiang, Qingtang 7 Prestin, Jurgen 6 Protasov, Vladimir Yu. 6 Roşca, Daniela 5 Berg, Lothar 5 Krüppel, Manfred 5 Li, Song 5 Potts, Daniel 5 Romani, Lucia 5 Sun, Qiyu 5 Yomdin, Yosef 4 Aldroubi, Akram 4 Bendory, Tamir 4 Cui, Lihong 4 Goldman, Gil 4 Jia, Rong-Qing 4 Kunis, Stefan 4 Li, Baobin 4 Peng, Lizhong 4 Perera, Sirani M. 4 Shen, Zuowei 4 Yang, Jianbin 3 Ashino, Ryuichi 3 Beinert, Robert 3 Bittens, Sina Vanessa 3 Cabrelli, Carlos A. 3 Chen, Hanlin 3 Cuyt, Annie A. M. 3 Huang, Yongdong 3 Iske, Armin 3 Iwen, Mark A. 3 Jetter, Kurt 3 Krishtal, Ilya Arkadievich 3 Lee, Wen-shin 3 Peter, Thomas 3 Putinar, Mihai 3 Ron, Amos 3 Sauer, Tomas 3 Sheng, Qiuhui 3 Steidl, Gabriele 3 Unser, Michael A. 3 von der Ohe, Ulrich 3 Wannenwetsch, Katrin 3 Xie, Changzhen 3 Zhang, Qingyue 3 Zhou, Dingxuan 2 Akinshin, Andrey 2 Andersson, Fredrik K. 2 Batenkov, Dmitry 2 Bergmann, Ronny 2 Britaňák, Vladimír 2 Budinich, Renato 2 Bultheel, Adhemar François 2 Carlsson, Marcus 2 Chui, Charles Kam-tai 2 Daubechies, Ingrid Chantal 2 Dekel, Shai 2 Edidin, Dan 2 Forster, Brigitte 2 Gao, Xieping 2 Goh, Say Song 2 Guglielmi, Nicola 2 Heil, Christopher E. 2 Holhoş, Adrian 2 Lebedeva, Elena A. 2 Lian, Jian’ao 2 Liu, Jianhua 2 Lou, Yifei 2 Marchesini, Stefano 2 Möller, Hans Michael 2 Molter, Ursula Maria 2 Peng, Silong 2 Ruch, David K. 2 Sauer, Thomas 2 Sprengel, Frauke 2 Stampfer, Kilian 2 Tang, Sui 2 Tenorth, Stefanie 2 Teo, Kok-Ming 2 Vaillancourt, Rémi 2 Van Fleet, Patrick J. 2 Zeng, Tie Yong 2 Zhang, Ruochuan 1 Abascal, Juan-Felipe P. J. 1 Akhtar, Md. Nasim 1 Alkhidhr, Hanan 1 Aràndiga, Francesc 1 Arnal, Romain D. 1 Arriëns, Huibert J. Lincklaen 1 Asaeedi, Saeed 1 Atreas, Nikolaos D. 1 Averbuch, Amir Z. 1 Aziznejad, Shayan ...and 289 more Authors
all top 5
Cited in 84 Serials
29 Applied and Computational Harmonic Analysis 18 Advances in Computational Mathematics 18 International Journal of Wavelets, Multiresolution and Information Processing 17 Journal of Approximation Theory 14 The Journal of Fourier Analysis and Applications 13 Journal of Computational and Applied Mathematics 10 Results in Mathematics 9 Computers & Mathematics with Applications 9 Journal of Mathematical Analysis and Applications 9 Numerical Algorithms 9 Acta Mathematica Sinica. English Series 8 Mathematics of Computation 7 Inverse Problems 7 Linear Algebra and its Applications 6 Applied Mathematics and Computation 4 Proceedings of the American Mathematical Society 4 Constructive Approximation 3 Numerical Functional Analysis and Optimization 3 Numerische Mathematik 3 Computer Aided Geometric Design 3 Applied Numerical Mathematics 3 SIAM Journal on Imaging Sciences 2 Applicable Analysis 2 Journal of Functional Analysis 2 Proceedings of the Edinburgh Mathematical Society. Series II 2 Transactions of the American Mathematical Society 2 Zeitschrift für Analysis und ihre Anwendungen 2 Journal of Symbolic Computation 2 Journal of Complexity 2 SIAM Journal on Matrix Analysis and Applications 2 Science in China. Series A 2 Signal Processing 2 St. Petersburg Mathematical Journal 2 ETNA. Electronic Transactions on Numerical Analysis 2 Abstract and Applied Analysis 2 Journal of Applied Mathematics and Computing 2 Analysis in Theory and Applications 2 Analysis and Applications (Singapore) 2 Science in China. Series F 2 Complex Analysis and Operator Theory 2 Science China. Mathematics 2 SIAM Journal on Applied Algebra and Geometry 1 Computer Methods in Applied Mechanics and Engineering 1 Journal of Computational Physics 1 Journal of the Franklin Institute 1 Lithuanian Mathematical Journal 1 Rocky Mountain Journal of Mathematics 1 Chaos, Solitons and Fractals 1 BIT 1 Czechoslovak Mathematical Journal 1 Mathematics and Computers in Simulation 1 Mathematische Nachrichten 1 Monatshefte für Mathematik 1 SIAM Journal on Numerical Analysis 1 Theoretical Computer Science 1 Circuits, Systems, and Signal Processing 1 Discrete & Computational Geometry 1 Computational Mechanics 1 Applied Mathematics Letters 1 Mathematical and Computer Modelling 1 Multidimensional Systems and Signal Processing 1 International Journal of Computer Mathematics 1 SIAM Journal on Mathematical Analysis 1 Acta Mathematica Sinica. New Series 1 The Journal of Analysis 1 Turkish Journal of Mathematics 1 ELA. The Electronic Journal of Linear Algebra 1 Mathematical Problems in Engineering 1 The ANZIAM Journal 1 Foundations of Computational Mathematics 1 Sampling Theory in Signal and Image Processing 1 GAMM-Mitteilungen 1 Frontiers of Mathematics in China 1 Inverse Problems and Imaging 1 EURASIP Journal on Advances in Signal Processing 1 Mathematical Geosciences 1 Proceedings of the Estonian Academy of Sciences 1 Journal of Singularities 1 Acta Crystallographica. Section A 1 Information and Inference 1 Axioms 1 Mathematical Sciences 1 Journal of Classical Analysis 1 SMAI Journal of Computational Mathematics
all top 5
Cited in 36 Fields
167 Harmonic analysis on Euclidean spaces (42-XX) 142 Numerical analysis (65-XX) 73 Information and communication theory, circuits (94-XX) 72 Approximations and expansions (41-XX) 20 Linear and multilinear algebra; matrix theory (15-XX) 19 Computer science (68-XX) 18 Difference and functional equations (39-XX) 13 Functional analysis (46-XX) 12 Operator theory (47-XX) 7 Operations research, mathematical programming (90-XX) 6 Functions of a complex variable (30-XX) 5 Number theory (11-XX) 5 Commutative algebra (13-XX) 5 Special functions (33-XX) 5 Partial differential equations (35-XX) 5 Statistics (62-XX) 4 Algebraic geometry (14-XX) 4 Geophysics (86-XX) 4 Systems theory; control (93-XX) 3 Real functions (26-XX) 3 Integral transforms, operational calculus (44-XX) 3 Calculus of variations and optimal control; optimization (49-XX) 3 Mechanics of deformable solids (74-XX) 3 Statistical mechanics, structure of matter (82-XX) 2 Ordinary differential equations (34-XX) 2 Integral equations (45-XX) 2 Biology and other natural sciences (92-XX) 1 Combinatorics (05-XX) 1 Field theory and polynomials (12-XX) 1 Measure and integration (28-XX) 1 Sequences, series, summability (40-XX) 1 Geometry (51-XX) 1 Convex and discrete geometry (52-XX) 1 Global analysis, analysis on manifolds (58-XX) 1 Optics, electromagnetic theory (78-XX) 1 Astronomy and astrophysics (85-XX)
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https://www.mcs.anl.gov/research/projects/otc/InteriorPoint/abstracts/Anjos-Wolkowicz-1.html
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## A Strengthened SDP Relaxation via a Second Lifting for the MAX-CUT Problem
### Miguel Anjos and Henry Wolkowicz
We present a strengthened semidefinite programming, SDP, relaxation for the Max-Cut problem, MC, and for the general quadratic boolean maximization problem. The well-known SDP relaxation can be obtained via Lagrangian relaxation and results in an SDP with variable $X \in {\cal S}^n$, the space of $n \times n$ symmetric matrices, and $n$ constraints, $\diag(X)=e,$ where $e$ is the vector of ones. The strengthened bound is based on applying a {\em lifting procedure} to this well-known semidefinite relaxation after adding the nonlinear constraints $X^2-nX=0$ and $X\circ X=E.$ The lifting procedure is again done via Lagrangian relaxation and results in an SDP with variable $Y \in {\cal S}^{t(n-1)+1}$, where $t(r)=r(r+1)/2,$ and $2t(n-1)+1$ constraints. It is shown that the new bound obtained this way strictly improves the previous SDP bound, both empirically and theoretically.
Technical Report CORR-55 October, 1999 University of Waterloo Department of Combinatorics and Optimization Waterloo, Ontario N2L 3G1, Canada
Contact: [email protected]
| 2021-09-27T03:31:11 |
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|
https://wiki.cosmos.esa.int/planckpla2015/index.php?title=Sky_temperature_maps&oldid=11043
|
# Sky temperature and polarization maps
## General description
Sky maps give the best estimate of the intensity and polarization (Stokes Q and U components), if available, of the signal from the sky after removal, as far as possible, of known systematic effects (mostly instrumental, but including also the solar and earth-motion dipole, Galactic strylight and the Zodiacal light). Sky maps are provided for the full Planck mission using all valid detectors in each frequency channel, and also for various subsets by splitting the mission in various time ranges or in subsets of the detectors in a given channel. These products are useful for the study of source variability, but they are especially interesting for characterisation purposes (see also the data validation section). The details of the start and end of the time ranges are given in the table below.
To help in further processing, there are also masks of the Galactic Plane and of point sources, each provided for several different depths.
All sky maps are in Healpix format, with Nside of 1024 (LFI 30, 44 and 70) and 2048 (LFI 70 and HFI), in Galactic coordinates, and Nested ordering. The signal is given in units of Kcmb for 30-353 GHz, and of MJy/sr (for a constant energy distribution ) for 545 and 857 GHz. For each frequency channel, the intensity and polarization maps are packaged into a BINTABLE extension of a FITS file together with a hit-count map (or hit map, for short, giving the number of observation samples that are cumulated in a pixel, all detectors combined) and with the variance and covariance maps. Additional information is given in the FITS file header. The structure of the FITS file is given in the FITS file structure section below.
Ranges for mission and surveys
Range ODs HFI rings pointing-IDs Comment
nominal mission 91 - 563 240 - 14723 00004200 - 03180200
full mission 91 - 974 240 - 27005 00004200 - 05322620 for HFI
full mission 91 - 1543 n/a 00004200 - 06511160 for LFI
Survey 1 91 - 270 240 - 5720 00004200 - 01059820
Survey 2 270 - 456 5721 - 11194 01059830 - 02114520
Survey 3 456 - 636 11195 - 16691 02114530 - 03193660
Survey 4 636 - 807 16692 - 21720 03193670 - 04243900
Survey 5 807 - 974 21721 - 27005 05267180 - 05322590 end of mission for HFI
Survey 5 807 - 993 n/a 05267180 - 06344800 end of survey for LFI
Survey 6 993 - 1177 n/a 06344810 - 06398120 LFI only
Survey 7 1177 - 1358 n/a 06398130 - 06456410 LFI only
Survey 8 1358 - 1543 n/a 06456420 - 06511160 LFI only
Survey 9 1543 - 1604 n/a 06511170 - 06533320 LFI only Not in this delivery
HFI mission-half-1 91 - 531 240 - 13471 00004200 - 03155580
HFI mission-half-2 531 - 974 13472 - 27005 03155590 - 05322590
LFI Year 1 91 - 456 n/a 00004200 - 02114520
LFI Year 2 456 - 807 n/a 02114530 - 04243900
LFI Year 3 807 - 1177 n/a 05267180 - 06398120
LFI Year 4 1177 - 1543 n/a 06398130 - 06511160
## Production process
Sky maps are produced by combining appropriately the data of all working detectors in a frequency channel over some period of the mission. They give the best estimate of the signal from the sky (unpolarised) after removal, as far as possible, of known systematic effects and of the dipole signals induced by the motion of the solar system in the CMB and of the Planck satellite in the solar system. In particular, they include the Zodiacal light emission (Zodi for short) and also the scattering from the far-side lobes of the beams (FSL). More on this below.
### HFI processing
The mapmaking and calibration process is described in detail in the Map-making section and in the mapmaking paper, where detailed references are found. In brief it consists of:
binning the TOI data onto rings
Healpix rings (HPRs) are used here, each ring containing the combined data of one pointing period.
flux calibration
at 100-353 GHz, the flux calibration factors are determined by correlating the signal with the orbital dipole, which is determined very accurately from the Planck satellite orbital parameters provided by Flight Dynamics. This provides a single gain factor per bolometer. At 545 and 857 GHz the gain is determined from the observation of Uranus and Neptune (but not Jupiter which is too bright) and comparison to recent models made explicitly for this mission. A single gain is applied to all rings at these frequencies.
destriping
in order to remove low-frequency noise, an offset per ring is determined by minimizing the differences between HPRs at their crossings, and removed.
Zodiacal light correction
a Zodiacal light model is used to build HPRs of the the Zodi emission, which is subtracted from the calibrated HPRs.
projection onto the map
the offset-corrected, flux-calibrated, and Zodi-cleaned HPRs are projected onto Healpix maps, with the data of each bolometer weighted by a factor of 1/NET of that bolometer.
These steps are followed by some post-processing which is designed to prepare the maps for the component separation work. This post processing consists of:
Dust bandpass leakage correction
the Q and U maps are corrected for the dust leakage due to the different bandpasses that is determined using the ground method as described here
Far Side Lobe calibration correction
the 100-217 maps are multiplied by factors of 1.00087, 1.00046, and 1.00043, respectively, to compensate for the non-removal of the far-side lobes, and similarly the corresponding covariance maps have also been corrected by multiplication by the square of the factor.
Fill missing pixels
missing pixels are filled in with a value that is the mean of valid pixels within a given radius. A radius of 1 deg is used for the full channel maps, and 1.5 deg is used for the detset maps. This step is not applied to the single survey maps since they have large swaths of the sky that are not covered.
These maps provide the main mission products. Together with signal maps, hit count, variance, and variance maps are also produced. The hit maps give the (integer) number of valid TOI-level samples that contribute to the signal of each pixel. All valid samples are counted in the same way, i.e., there is no weighting factor applied. The variance maps project the white noise estimate, provided by the NETs, in the sky domain.
Note that the nominal mission maps have not had the post-processing applied, which makes them more easily comparable to the PR1 products.
### LFI processing
Input timelines are cleaned by 4pi convolved dipole and Galactic Straylight obtained as convolution of the 4pi in band far sidelobes and Galactic Simulation
LFI maps were constructed with the Madam map-making code, version 3.7.4. The code is based on generalized destriping technique, where the correlated noise component is modeled as a sequence of constant offset, called baselines. A noise filter was used to constrain the baseline solution allowing the use of 1 second baselines.
Radiometers were combined according to the horn-uniform weighting scheme to minimize systematics. The used weights are listed in Map-making. The flagged samples were excluded from the analysis by setting their weights to = 0. The galaxy region was masked out in the destriping phase, to reduce error arising from strong signal gradients. The polarization component was included in the analysis...
A detailed description of the map-making procedure is given in Planck-2013-II[1]Planck-2015-A07[2] and in section Map-making.
## Types of maps
### Full mission, full channel maps (6 HFI, 4 LFI)
Full channel maps are built using all the valid detectors of a frequency channel and cover the either the full or the nominal mission. For HFI, the 143-8 and 545-3 bolometers are rejected entirely as they are seriously affected by RTS noise. For this release, HFI provides the Q and U components for the 353 GHz channel only. LFI provides the I, Q and U maps for all the channels. The I maps are displayed in the figures below. The color range is set using a histogram equalisation scheme (from HEALPIX) that is useful for these non-Gaussian data fields. The Q and U maps are not shown as they look like noise to the naked eye. The 70 GHz full map is available also at Nside 2048.
### Nominal mission, full channel maps (6 HFI)
These maps are similar to the ones above, but cover the nominal mission only. They are meant primarily to be compared to the PR1 products in order to see the level of improvements in the processing. Because of this, they are produced in Temperature only, and have not had the post-processing applied.
### Single survey, full channel maps (30 HFI, 35 LFI)
Single survey maps are built using all valid detectors of a frequency channel; they cover separately the different sky surveys. The surveys are defined as the times over which the satellite spin axis rotates but 180 degrees, which, due to the position of the detectors in the focal plane does not cover the full sky, but a fraction between ~80 and 90% depending on detector position. During adjacent surveys the sky is scanned in opposite directions. More precisely it is the ecliptic equator that is scanned in opposite directions. While these are useful to investigate variable sources, they are also used to study the systematics of the time-response of the detectors as they scan bright sources, like the Galactic Plane, in different directions during different survey. Note that the HFI and LFI missions cover 5 and 8 surveys, respectively, and in case of HFI the last survey in incomplete. The 70 GHz surveys maps are available also at Nside 2048. Note LFI provide a special surveys maps combination used in the low l analysis. This maps, available at the three LFI frequency 30, 44 and 70 GHz, was built using the combination of survey 1, 3, 5, 6, 7 and 8.
### Year maps, full channel maps (12 HFI, 16 LFI)
These maps are built using the data of surveys 1+2, surveys 3+4, and so forth. They are used to study long-term systematic effects. The 70 GHz years maps are available also at Nside 2048.
### Half-mission maps, full channel maps (12 HFI, 12 LFI)
For HFI, the half mission is defined after eliminating those rings discarded for all bolometers. There are 347 such rings, may of which are during the 5th survey when the End-of-Life tests were performed. The remaining 26419 rings are divided in half (up to the odd ring) to define the two halves of the mission. This exercise is done for the full mission only.
For LFI instead of the half-mission the following year combination has been created: Year 1+2, Year 1+3, Year 2+4, Year 3+4,
### Full mission, single detector maps (18 HFI, 22 LFI)
IN case of HFI these maps are built only for the SWBs (non polarized) and contain only temperature data, of course. They are not built for the polarisation sensitive detectors because they are not fixed on the sky as the polarisation component depends on the position angle at the time of observation. Instead, we provide maps built by quads of polarisation-sensitive detectors (see next section), which have different polarisation angles and that can be used to built I, Q, and U maps
HFI Temperature sensitive bolometers
Frequency Detector names
143 GHz 143-5, 6, 7
217 GHz 217-1, 2, 3, 4
353 GHz 353-1, 2, 7, 8
545 GHz 545-1, 2, 4
857 GHz 857-1, 2 , 3, 4
The 143-8 and 353-3 bolometer data are affected by strong RTS (random telegraphic signal) noise. They have not been used in the data processing, and are not delivered. For a figure showing the focal plane layout, see this Introduction of the Detector Pointing chapter.
In case of LFI, all the 22 Radiometers maps are available, those, obviously, are only in temperature.
### Full mission, detector set or detector pairs maps (8 HFI, 8 LFI)
The objective here is to build independent temperature (I) and polarisation (Q and U) maps with the two pairs of polarisation sensitive detectors of each channel where they are available, i.e. in the 44-353 GHz channels. The table below indicates which detectors were used to built each detector set (detset).
Definition of HFI Detector Sets
Frequency DetSet1 DetSet2
100 GHz 100-1a/b & 100-4a/b 100-2a/b & 100-3a/b
143 GHz 143-1a/b 1 & 43-3a/b 143-2a/b & 143-4a/b
217 GHz 217-5a/b & 217-7a/b 217-6a/b & 217-8a/b
353 GHz 353-3a/b & 353-5a/b 353-4a/b & 353-6a/b
Definition of LFI Detector Pairs
Frequency Horn Pair Comment
44 GHz 24 This maps is only in temperature
44 GHz 25 & 26
70 GHz 18 & 23 Available also at Nside = 2048
70 GHz 19 & 22 Available also at Nside = 2048
70 GHz 20 & 21 Available also at Nside = 2048
### Half-ring maps (64 HFI, 62 LFI)
These maps are similar to the ones above, but are built using only the first or the second half of each ring (or pointing period). The HFI provides half-ring maps for the full mission only, and for the full channel, the detsets, and the single bolometers. The LFI provides half-rings maps for the channel full mission (70 GHz also at Nside 2048), for the radiometer full mission and the horn pairs full mission.
### The Zodiacal light correction maps
The Zodiacal light signal depends on the location of the observer relative to the Zodiacal light bands, and thus it is not a fixed pattern on the sky but depends on the period of observation. The maps presented here are the difference between the uncorrected (and not delivered) and the corrected maps.
### Caveats and known issues
TBW
#### Map zero-level
For the 100 to 857 GHz maps, the zero levels are set to their optimal levels for Galactic and CIB studies. A procedure for adjusting them to astrophysical values is given in the HFI Mapmaking and Calibration paper [3].
For the 30, 44 and 70 GHz, maps are corrected for zero level monopole by applying an offset correction, see LFI Calibration paper Planck-2013-V[4] section 3.4 "Setting the zero levels in the maps" and Planck-2015-A06[5]. Note that the offset applied is indicated in the header as a comment keyword.
## Inputs
### HFI inputs
• The cleaned TOIs of signal of each detector, together with their flags, produced by the TOI processing pipeline
• The TOIs of pointing (quaternions), described in Detector pointing
• Bolometer-level characterization data, from the DPC's internal IMO (not distributed)
• Planck orbit data used to compute and remove the earth dipole
• Planck solar dipole information used to calibrate the CMB channels
• Planet models used to calibrate the Galactic channels.
### LFI inputs
The Madam map-maker takes as an input:
• The calibrated timelines (for details see TOI Processing)
• The detector pointings (for details see Detector pointing)
• The noise information in the form of three-parameter (white noise level (), slope, and knee frequency ($f_\mathrm{knee}$)) noise model (for details see RIMO)
## Related products
This section presents the masks of the point sources and of the Galactic plane. These are general purpose masks. Other masks specific to certain products are packaged with the products.
#### Point source masks
For HFI and LFI two sets of masks are provided:
• Intensity masks, which removes sources detected with SNR > 5.
• Polarisation masks, which remove sources which have polarisation detection significance of 99.97 % or greater at the position of a source detected in intensity. They were derived from the polarisation maps with dust ground bandpass mismatch leakage correction applied. The cut around each source has a radius of 3σ (width) of the beam ~ 1.27 FWHM (for LFI the cut around each source has a radius of 32 arcmin at 30GHz, 27 arcmin at 44 GHz and 13 arcmin at 70 GHz).
Both sets are found in the file HFI_Mask_PointSrc_2048_R2.00.fits in which the first extension contains the Intensity masks, and the second contains the Polarisation masks.
#### Galactic Plane masks
Eight masks are provided giving 20, 40, 60, 70, 80, 90, 97, and 99% sky coverage derived from the 353 GHz map, after CMB subtraction. They are independent of frequency channel. Three versions of these are given: not apodized, and apodized by 2 and 5 deg. The filenames are HFI_Mask_GalPlane-apoN_2048_R2.00.fits, where N = 0, 2, 5.
The masks are shows below. The 8 GalPlane masks are combined (added together) and shown in a single figure for each of the three apodization. While the result is quite clear for the case of no apodization, it is less so for the apodized case. The point source masks are shown separately for the Intensity case.
## File names
The FITS filenames are of the form {H|L}FI_SkyMap_fff{-tag}_Nside_R2.nn_{coverage}-{type}.fits, where fff are three digits to indicate the Planck frequency band, tag indicates the single detector or the detset, Nside is the Healpix Nside of the map, coverage indicates which part of the mission is covered (full, half mission, survey, year, ...) , and the optional type indicates the subset of input data used. The table below lists the products by type, with the appropriate unix wildcards that form the full filename.
HFI FITS filenames
Coverage filename half-ring filename
Full chan, full mission HFI_SkyMap_???_2048_R2.??_full.fits HFI_SkyMap_???_2048_R2.??_full-ringhalf-?.fits
Full channel, nominal mission HFI_SkyMap_???_2048_R2.??_nominal.fits n/a
Full channel, single survey HFI_SkyMap_???_2048_R2.??_survey-?.fits n/a
Full channel, single year HFI_SkyMap_???_2048_R2.??_year-?.fits n/a
Full channel, half mission HFI_SkyMap_???_2048_R2.??_halfmission*-?.fits n/a
Det-set, full mission HFI_SkyMap_???-ds?_2048_R2.??_full.fits HFI_SkyMap_???-ds?_2048_R2.??_full-ringhalf-?.fits
Single SWB, full mission HFI_SkyMap_???-?_2048_R2.??_full.fits HFI_SkyMap_???-?_2048_R2.??_full-ringhalf-?.fits
LFI FITS filenames
Coverage filename half-ring filename Comment
Full channel, full mission LFI_SkyMap_???_1024_R2.??_full.fits LFI_SkyMap_???_1024_R2.??_full-ringhalf-?.fits Available also at Nside = 2048
Full channel, single survey LFI_SkyMap_???_1024_R2.??_survey-?.fits n/a Available also at Nside = 2048
Full channel, survey combination LFI_SkyMap_???_1024_R2.??_survey-1-3-5-6-7-8.fits n/a n/a
Full channel, single year LFI_SkyMap_???_1024_R2.??_year-?.fits n/a Available also at Nside = 2048
Full channel, year combination LFI_SkyMap_???_1024_R2.??_year?-?.fits n/a n/a
Horn pair, full mission LFI_SkyMap_???-??-??_1024_R2.??_full.fits LFI_SkyMap_???_??-??_1024_R2.??_full-ringhalf-?.fits Available also at Nside = 2048
Single radiometer, full mission LFI_SkyMap_???-???_1024_R2.??_full.fits LFI_SkyMap_???-???_1024_R2.??_full-ringhalf-?.fits n/a
For the benefit of users who are only looking for the frequency maps with no additional information, we also provide a file combining the 9 frequency maps as separate columns in a single extension. The 9 columns in this file contain the intensity maps ONLY and no other information (hit maps and variance maps) is provided.
## FITS file structure
The FITS files for the sky maps contain a minimal primary header with no data, and a BINTABLE extension (EXTENSION 1, EXTNAME = FREQ-MAP) containing the data. The structure is shows schematically in the figure below. The FREQ-MAP extension contains a 3- or a 10-column table that contain the signal, hit-count and variance maps, all in Healpix format. The 3-column case is for intensity only maps, the 10-column case is for polarisation. The number of rows is the number of map pixels, which is Npix = 12 Nside2 for Healpix maps, where Nside = 1024 or 2048 for most the maps presented in this chapter.
FITS file structure
Note that file sizes are ~0.6 GB for I-only maps and ~1.9 GB for I,Q,U maps at Nside 2048 and ~0.14 GB for I-only maps and ~0.45 GB for I,Q,U maps at Nside 1024 .
Keywords indicate the coordinate system (GALACTIC), the Healpix ordering scheme (NESTED), the units (K_cmb or MJy/sr) of each column, and of course the frequency channel (FREQ). Where polarisation Q and U maps are provided, the COSMO polarisation convention (used in HEALPIX) is adopted, and it is specified in the POLCCONV keyword (see this section. The COMMENT fields give a one-line summary of the product, and some other information useful for traceability within the DPCs. The original filename is also given in the FILENAME keyword. The BAD_DATA keyword gives the value used by Healpix to indicate pixels for which no signal is present (these will also have a hit-count value of 0). The main parameters are summarised below:
Sky map file data structure
1. EXTNAME = 'FREQ-MAP' : Data columns
Column Name Data Type Units Description
I_STOKES Real*4 K_cmb or MJy/sr The Stokes I map
Q_STOKES Real*4 K_cmb or MJy/sr The Stokes Q map (optional)
U_STOKES Real*4 K_cmb or MJy/sr The Stokes U map (optional)
HITS Int*4 none The hit-count map
II_COV Real*4 K_cmb2 or (MJy/sr)2 The II variance map
IQ_COV Real*4 K_cmb2 or (MJy/sr)2 The IQ variance map (optional)
IU_COV Real*4 K_cmb2 or (MJy/sr)2 The IQ variance map (optional)
QQ_COV Real*4 K_cmb2 or (MJy/sr)2 The QQ variance map (optional)
QU_COV Real*4 K_cmb2 or (MJy/sr)2 The QU variance map (optional)
UU_COV Real*4 K_cmb2 or (MJy/sr)2 The UU variance map (optional)
Keyword Data Type Value Description
PIXTYPE string HEALPIX
COORDSYS string GALACTIC Coordinate system
ORDERING string NESTED Healpix ordering
POLCCONV String COSMO Polarization convention
NSIDE Int 1024 or 2048 Healpix Nside
FIRSTPIX Int*4 0 First pixel number
LASTPIX Int*4 12 Nside2 – 1 Last pixel number
FREQ string nnn The frequency channel
The same structure applies to all SkyMap products, independent of whether they are full channel, survey of half-ring. The distinction between the types of maps is present in the FITS filename (and in the traceability comment fields).
## Polarization convention used in the Planck project
The Planck collaboration used the COSMO convention for the polarization angle (as usually used in space based CMB missions), whereas other astronomical fields usually use the IAU convention. In the following document we report the difference between these two conventions, and the consequence if it is NOT taken into account correctly in the analysis.
Figure 1. COSMO convention (left) and IAU convention (right). The versor points outwards the pointing direction in COSMO, and inwards in IAU. The bottom panel refers to the plane tangent to the sphere.
Changing the orientation convention is equivalent to a transformation of the polarization angle (Figure 1). The consequence of this transformation is the inversion of the Stokes parameter . The components of the polarization tensor in the helicity basis are:
where are the spin weighted spherical harmonic functions. The and modes can be defined as:
where the coefficients and are derived from linear combinations of the , defined implicitly in the first equation ().
Figure 2. Error on Planck-LFI 70 GHz (top) and (bottom) spectra, in case of wrong choice of the coordinate system convention (IAU instead of COSMO).
The effect of the sign inversion of on the polarization spectra is a non trivial mixing of and modes.
An example of the typical error on and auto-spectra in case of a wrong choice of the polarization basis is shown in Figure 2.
BE CAREFUL about the polarization convention you are using. If the IAU convention is used in computing the power spectra, the sign of the component of the Planck maps must be inverted before computing and modes.
### Note on the convention used by the Planck Catalog of Compact Sources (PCCS)
For continuity with other compact sources catolgues, the Catalogue of Compact Sources provided by Planck follows the IAU convention, and the polarization angles are defined on an interval of [-90,90] degrees. To switch to the COSMO convention, the polarization angles listed in the catalogue have to be shifted by 90 degrees and multiplied by -1.
## References
1. Planck 2013 results. II. Low Frequency Instrument data processing, Planck Collaboration, 2014, A&A, 571, A2
2. Planck 2015 results. VI. LFI mapmaking, Planck Collaboration, 2016, A&A, 594, A6.
3. Planck 2013 results. V. LFI Calibration, Planck Collaboration, 2014, A&A, 571, A5
4. Planck 2015 results. V. LFI calibration, Planck Collaboration, 2016, A&A, 594, A5.
(Planck) Low Frequency Instrument
(Planck) High Frequency Instrument
Flexible Image Transfer Specification
Cosmic Microwave background
[LFI meaning]: absolute calibration refers to the 0th order calibration for each channel, 1 single number, while the relative calibration refers to the component of the calibration that varies pointing period by pointing period.
Noise Equivalent Temperature
random telegraphic signal
Data Processing Center
Full-Width-at-Half-Maximum
| 2022-05-26T12:08:00 |
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|
https://www.pmel.noaa.gov/maillists/tmap/ferret_users/fu_95/msg00017.html
|
# Re: ferret to .eps
```On Nov 9, 10:29am, S.P. Jewson wrote:
> Subject: ferret to .eps
>
> I'm looking for ways to include ferret output in a latex document.
>
> Using 'set mode meta' and gksm2ps/Fprint results in a .ps file
> which cannot be resized within the latex document.
>
> The best way round this that I have found is to use the freeware
> ImageMagick-display to rotate the plot and resave as .eps format.
> This can then be resized within latex.
> This, however, results in a loss of quality.
>
> My question: is there a better way to do this?
> Can the .plt files be converted directly into .eps files?
> Can the .ps output from gksm2ps be edited to rotate it
> and make it resizable in latex?
This one threw me for a while too.
First thing, the gksm2ps output is not strictly EPS compliant. There is a line
in the postscript that causes problems when trying to include the graphic in a
LaTeX file. The best way to exclude the problematic line is to use grep. For
example:
grep -v initmatrix FILENAME.ps > NEWFILENAME.ps
This will exclude a line that contains the command `initmatrix' from the
postscript file. Now you can include the EPS file in a LaTeX document. (You
could also just edit the .ps file, search for initmatrix and delete the whole
line.
The best way I have found for including postscript files in LaTex is via the
pstricks macros written by Timothy Van Zandt. This is freeware, and should be
available at CTAN archives, if I remember correctly. This gives you a lot more
flexibility than anything else I have tried. Here is a brief example:
In the document declaration include epsf and pstricks:
Then to include a graphic:
\pspicture(0,0)(8.4,9.4)
% \psgrid
\epsfxsize=8.1cm
\rput(4.4,5.2){\epsfbox{pacio_plots/pacio.ps}}
\endpspicture
The pspicture declares the positioning of a graphics "space" in the document,
psgrid turns on a useful underlying grid, that helps with positioning and
sizing, epsfxsize is the usual scaling command,
rput allows positioning and rotation of the graphic, epsfbox include the eps
file.
It's pretty quick and dirty. Plus there are alot of other nice tricks in the
pstricks macros that I find useful.
Hope this helps! Mark
--
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Mark Verschell ([email protected])
Center for Ocean and Atmospheric Prediction Studies
020 Love Building
Florida State University
Tallahassee, FL 32306-3041
(904) 644-6532
(904) 644-4841 (fax)
```
| 2022-07-01T19:24:12 |
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|
https://tjyj.stats.gov.cn/CN/Y2015/V32/I7/81
|
• 论文 •
### 遥感辅助的农作物种植面积小域估计方法研究
• 出版日期:2015-07-15 发布日期:2015-07-17
### A Study on Small Area Estimation for Crop Acreage in Remote Sensing Assisted Crop Survey
Zhou Wei etal
• Online:2015-07-15 Published:2015-07-17
Abstract: Remote sensing imagery is one form of the big data. It typically uses regression estimator or calibration estimator to estimate the planted acreage by applying remote sensing. Therefore, it’s necessary to combine the sample data from ground survey with satellite image classification. For most cases of regression estimator, the estimation of provincial crop acreage only satisfies the precision target for a province but could not disaggregate to small areas, such as county and town level statistics. This paper is adopted small area estimation approach to estimate crop acreage at county level in Heilongjiang province by combining ground survey data with image classification of the year 2011. A basic level small area model in the form of multi-response multiple regression with fixed effects is adopted to estimate acreage for major crops. Based on regression estimator, not only all county level estimation is produced but also the constraint that the aggregate of county level estimates could be equal to the estimate for entire province under linear model is satisfied.
| 2022-07-02T04:54:11 |
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|
https://pavpanchekha.com/blog/herbie-goals.html
|
## By Pavel Panchekha
### 07 April 2019
Share under CC-BY-SA.
# Long-term Goals for Herbie
One of the most rewarding non-research tasks I've done in grad school is to maintain Herbie, a tool for automatically improving the accuracy of floating-point programs. I published Herbie at PLDI’15, which means that Herbie was largely done (as a research project) in 2014. But in the five years since, Herbie has had several major changes that have significantly improved it.
## Making Herbie more maintainable
Since I maintain Herbie in my free time (I have other research projects), making Herbie easier to maintain is a central goal. Picking an input format, a math library, and a sampling mechanism settled questions that otherwise had to be decided again and again.
The FPCore input format gave Herbie a standard, well-documented input format. It has a proper parser, with syntax and type checking, instead of eval-ing each input file, which provides better warnings and errors.
Supporting math.h gives Herbie a clear answer to what functions Herbie supports and how they are implemented. We sacrificed some convenience functions like sqr and cube, but we gained clarity.
Removing samplers, so Herbie always samples input points uniformly over bit patterns, removed a confusing and poorly-implemented feature. The main use for custom distributions was to efficiently sample from small ranges like 12 ≤ x ≤ 14. Now, Herbie uses a static analysis to do the same.
## Making Herbie more predictable
Often a good idea starts with a pile of supporting hacks and heuristics. Removing those bit by bit makes Herbie more reliable and eliminates errors and corner cases.
Herbie now soundly finds exact outputs for programs with interval-analysis, to correctly measure how much a program's accuracy. That used to involve heuristics. Heuristics are useful, but not in the part of Herbie that measures how well Herbie works.
Herbie's regime inference is better thanks to binary search, which generates accurate if statements that don't change by factors of ten with every run. Plus, regime inference now supports more types of conditions.
Making the web demo and HTML reports the standard interface to Herbie gives users more information about what Herbie did and made Herbie easier to use. I don't know if anyone even uses the command-line version any more.
Herbie now collects a lot of metrics about its internals and presents it in a pretty GUI. That makes it a lot easier to track down problems with accuracy and speed, and has helped make Herbie much faster.
## Future goals
I have high hopes Herbie will continue getting better—it's a fun project to work on, with real users, and leverage to improve the state of scientific computing.
Refactoring Herbie with multiple formats will separate the notion of a type and its representation. That will support mixed-precision programs and new formats like posits. It could also help make Herbie a platform for research into new FP data types.
Support for pluggable libraries means Herbie could be extended to support complex numbers, matrices, vectors, and all sorts of other libraries, potentially even by users. This could make Herbie much more useful to scientists.
Faster simplification is essential for speeding Herbie up, since simplification is now the majority of Herbie's runtime. Simplification is a bottleneck on the search process: if it were faster, Herbie could try more things and get better results.
The web interface should give users access to preconditions, precisions, or command-line flags. The web should be a first-class interface to Herbie. Developing UIs takes time, but it is worth it.
Herbie's core search algorithm is too focused, and often discards promising candidates too early. I think I know how to fix it. Even if it doesn't improve Herbie's results, it should remove a heuristic and make those results more reliable.
| 2023-02-07T21:47:26 |
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|
https://www.usgs.gov/faqs/what-do-bats-eat?qt-news_science_products=0
|
# What do bats eat?
Bats are the most significant predators of night-flying insects. There are at least 40 different kinds of bats in the U.S. that eat nothing but insects. A single little brown bat, which has a body no bigger than an adult human’s thumb, can eat 4 to 8 grams (the weight of about a grape or two) of insects each night. Although this may not sound like much, it adds up—the loss of the one million bats in the Northeast has probably resulted in between 660 and 1320 metric tons of insects no longer being eaten each year by bats.
Bats locate each insect by echolocation, then they trap it with their wing or tail membranes and reach down to take the insect into their mouth. This action, as well as the chase, results in the erratic flight most people are familiar with when they observe bats feeding in the late evening or around lights at night.
Other species of bats eat many different things, including fruit, nectar, and pollen. Bats are important pollinators as they fly from plant to plant in search of food. In the southwestern deserts of North America, bats are the key pollinators of saguaro and organ pipe cactus. Tequila is made from the agave plant, which is pollinated by bats.
## Related Content
Filter Total Items: 9
### Where do bats live?
Bats can be found in almost all parts of the world and in most regions of the United States. In general, bats seek out a variety of daytime retreats such as caves, rock crevices, old buildings, bridges, mines, and trees. Different species require different roost sites. Some species, such as the Mexican free-tailed and gray bats live in large...
### Why are bats important?
By eating insects, bats save U.S. agriculture billions of dollars per year in pest control. Some studies have estimated that service to be worth over $3.7 billion per year, and possibly as much as$53 billion. This value does not, however, take into account the volume of insects eaten by bats in forest ecosystems and the degree to which that...
### Are bats dangerous?
All healthy bats try to avoid humans by taking flight and are not purposely aggressive. Most bats are about the size of a mouse and use their small teeth and weak jaws to grind up insects. You should avoid handling bats because several species, such as the hoary and big brown bats, have large teeth that can puncture skin if they are handled...
### Do vampire bats really exist?
Yes, but not in most of the United States. Of the three species of vampire bats in North America, only a single specimen has been recorded for the United States in extreme southwest Texas. Vampire bats do not suck blood--they make a small incision with their sharp front teeth and lap up the blood with their tongue. Vampire bats in Mexico and South...
### Are bats blind?
No, bats are not blind. Bats have small eyes with very sensitive vision, which helps them see in conditions we might consider pitch black. They don’t have the sharp and colorful vision humans have, but they don’t need that. Think of bat vision as similar to a dark-adapted Mr. Magoo (a cartoon character with very poor vision). Learn more at the...
### How are bats affected by wind turbines?
Dead bats are found beneath wind turbines all over the world. It’s estimated that tens to hundreds of thousands die at wind turbines each year in North America alone. Unfortunately, it’s not yet clear why this is happening. It’s possible that wind turbines interfere with seasonal migration and mating patterns in some species of bats. More than...
### What species of bats are affected by White-nose Syndrome?
White-nose Syndrome mostly affects hibernating bats. More than half of the 47 bat species living in the United States and Canada hibernate to survive the winter. Thirteen bat species, including two endangered species and one threatened species, have been confirmed with white-nose syndrome in North America. The causative fungus, Pseudogymnoascus...
### What should I do if I find dead or dying bats, or if I observe bats with signs of White-nose Syndrome?
If you find a dead or dying bat: Contact your state wildlife agency, file an electronic report in those states that offer this service, e-mail U.S. Fish and Wildlife Service biologists in your area, or contact your nearest Fish and Wildlife Service field office to report your potential White-nose Syndrome (WNS) observations. It is important to...
### What is White-nose Syndrome?
White-nose syndrome is an emergent disease of hibernating bats that has spread from the northeastern to the central United States at an alarming rate. Since the winter of 2007-2008, millions of insect-eating bats in at least 33 states and seven Canadian provinces have died from this devastating disease. The disease is named for the white fungus,...
Filter Total Items: 4
Date published: June 22, 2020
### It’s Pollinator Week!
Pollinators in the form of bees, birds, butterflies, bats and beetles provide vital but often invisible services, from supporting terrestrial wildlife and plant communities, to supporting healthy watersheds.
Date published: October 28, 2019
### Trick or Treat? The Frightening Threats to Bats
Date published: January 17, 2017
### A Deadly Double Punch: Together, Turbines and Disease Jeopardize Endangered Bats
Date published: March 31, 2011
### Bats Worth Billions to Agriculture: Pest-control Services at Risk
Pest-control services provided by insect-eating bats in the United States likely save the U.S. agricultural industry at least \$3 billion a year, and yet insectivorous bats are among the most overlooked economically important, non-domesticated animals in North America, according to an analysis published in this week’s Science magazine Policy Forum.
Filter Total Items: 23
September 26, 2019
### PubTalk 09/2019 — Bats in the West
Title: Bats in the West: Discoveries, Questions, and Future Research
By Gabriel A. Reyes, USGS Biologist
• Learn about bat ecology, diversity, and the role they play in our ecosystem.
• See how scientists are using a variety of methods including capture, acoustic monitoring, and tracking, to learn more about local bat species.
• Find out how
August 1, 2018
### Pallid bat with transmitter
A Pallid bat (Antrozous pallidus) is outfitted with a radio transmitter to help lead us to its roost. The transmitter is attached with a temporary adhesive that will wear off within around 2 weeks, about as long as the battery life of the transmitter lasts. By following the bat USGS researchers will be able to learn what habitat types are important for this species,
...
December 31, 2017
### Southeastern Bat with P. destructans Fungus
This southeastern bat (Myotis austroriparius) from Alabama shows signs of infection from the Pseudogymnoascus destructans fungus that causes white-nose syndrome in bats. The USGS National Wildlife Health Center later confirmed white-nose syndrome in this animal, marking the first time that WNS was found in a southeastern bat. As of June 2017, the species joins eight other
...
December 31, 2017
### Hibernating little brown bat
little brown bat (Myotis lucifugus) with white-nose syndrome hibernating in a Virginia cave during late spring of 2016. Patches of the fungus that causes white-nose syndrome can be seen growing out of the skin (white areas) near the nose and across the folded wing skin of this bat. Spherical drops of water condensation coat the bat's outer fur, a
...
October 16, 2017
### Western red bat release
Like most wild animals, bats often don't appreciate being handled for research purposes. However when holding bats after handling and examination, they often appreciate the warmth and need a little push to go. This Western red bat (Lasiurus blossevillii) was captured during USGS WERC research to learn more about the ecology, distribution, and movement patterns of
...
March 2, 2017
### Little brown bat with white-nose syndrome
Little brown bat with white-nose syndrome
December 31, 2016
### Dissected bat guano pellet showing antennae, eyes, and body parts
Dissected guano pellet showing antennae, eyes, and body fragments of midges.
December 19, 2016
### Mosquito, carrier of the Encephalitis virus
December 15, 2016
### Examples of Insect fragments from bat guano
Examples of Insect fragments belonging to ground beetles, water boatmen, click beetles, weevils, scarabs, and adult antlions identified from various dissected guano pellets of different studies.
December 15, 2016
### Allen's big-eared bat (Idionycteris phyllotis), an insectivore.
Allen's big-eared bat (Idionycteris phyllotis), an insectivore known from the southwestern United States.
October 26, 2016
A spotted bat.
June 27, 2016
| 2020-10-23T12:20:44 |
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|
https://par.nsf.gov/biblio/10225814-energy-resolution-linearity-xenon1t-mev-energy-range
|
Energy resolution and linearity of XENON1T in the MeV energy range
Abstract Xenon dual-phase time projection chambers designed to search for weakly interacting massive particles have so far shown a relative energy resolution which degrades with energy above $$\sim$$ ∼ 200 keV due to the saturation effects. This has limited their sensitivity in the search for rare events like the neutrinoless double-beta decay of $$^{136} \hbox {Xe}$$ 136 Xe at its Q value, $$Q_{\beta \beta }\simeq 2.46\,\hbox {MeV}$$ Q β β ≃ 2.46 MeV . For the XENON1T dual-phase time projection chamber, we demonstrate that the relative energy resolution at $$1\,\sigma /\mu$$ 1 σ / μ is as low as ( $$0.80 \pm 0.02$$ 0.80 ± 0.02 ) % in its one-ton fiducial mass, and for single-site interactions at $$Q_{\beta \beta }$$ Q β β . We also present a new signal correction method to rectify the saturation effects of the signal readout system, resulting in more accurate position reconstruction and indirectly improving the energy resolution. The very good result achieved in XENON1T opens up new windows for the xenon dual-phase dark matter detectors to simultaneously search for other rare events.
Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
Award ID(s):
Publication Date:
NSF-PAR ID:
10225814
Journal Name:
The European Physical Journal C
Volume:
80
Issue:
8
ISSN:
1434-6044
1. Abstract The DARWIN observatory is a proposed next-generation experiment to search for particle dark matter and for the neutrinoless double beta decay of $$^{136}$$ 136 Xe. Out of its 50 t total natural xenon inventory, 40 t will be the active target of a time projection chamber which thus contains about 3.6 t of $$^{136}$$ 136 Xe. Here, we show that its projected half-life sensitivity is $$2.4\times {10}^{27}\,{\hbox {year}}$$ 2.4 × 10 27 year , using a fiducial volume of 5 t of natural xenon and 10 year of operation with a background rate of less than 0.2 events/(t $$\cdot$$ · year) in the energymore »
4. Abstract We detail the sensitivity of the proposed liquid xenon DARWIN observatory to solar neutrinos via elastic electron scattering. We find that DARWIN will have the potential to measure the fluxes of five solar neutrino components: pp , $$^7$$ 7 Be, $$^{13}$$ 13 N, $$^{15}$$ 15 O and pep . The precision of the $$^{13}$$ 13 N, $$^{15}$$ 15 O and pep components is hindered by the double-beta decay of $$^{136}$$ 136 Xe and, thus, would benefit from a depleted target. A high-statistics observation of pp neutrinos would allow us to infer the values of the electroweak mixing angle, $$\sinmore » 5. Abstract The selection of low-radioactive construction materials is of utmost importance for the success of low-energy rare event search experiments. Besides radioactive contaminants in the bulk, the emanation of radioactive radon atoms from material surfaces attains increasing relevance in the effort to further reduce the background of such experiments. In this work, we present the$$^{222}$$${}^{222}$Rn emanation measurements performed for the XENON1T dark matter experiment. Together with the bulk impurity screening campaign, the results enabled us to select the radio-purest construction materials, targeting a$$^{222}$$${}^{222}$Rn activity concentration of$$10\,\mathrm{\,}\upmu \mathrm{Bq}/\mathrm{kg}$$$10\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}\mu \mathrm{Bq}/\mathrm{kg}$in$$3.2\,\mathrm{t}$$$3.2\phantom{\rule{0ex}{0ex}}t$of xenon. The knowledge of the distribution of the$$^{222}${}^{222}$Rn sources allowed us to selectivelymore »
| 2022-06-28T03:10:34 |
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|
http://www.stats.gov.cn/english/statisticaldata/yearlydata/YB1999e/ge.htm
|
Production and Consumption of Energy Brief Introduction I. the data in this chapter cover mainly the energy production and consumption and their composition, the elasticity ratio of energy production and consumption, the overall balance of energy and the balance by the variety of energy, the consumption of energy by sector and by main variety, efficiency of energy conversion and the consumption of energy for residential use. II. The national energy balance in this chapter is compiled by the Department of Industrial and Transport Statistics, NBS on the basis of data from surveys and from input-output tables. III. Coverage and calculation of Data: (1) the data on the production of primary energy are the same as the concerned data of the industrial statistics. (2) the state classification of national economic sectors is used in the classification of sectors. (3) the elasticity ratio of energy production is calculated as the quotient of the growth rate of energy production divided by the growth rate of GDP; And the elasticity ratio of energy consumption is calculated as the quotient of the growth rate of energy consumption divided by the growth rate of GDP. (4) in the energy balance, the data on the imports and exports are data from the customs statistics. the refueling by Chinese ships and airplanes abroad is included in the imports. The refueling by foreign ships and airplanes in China is included in the exports. The coefficient for conversion of electric power into the standard coal equivalent is calculated according to the average consumption of coal for generating electricity. (5) in the table on the efficiency of energy conversion, the coefficient for conversion of electric power into the standard coal equivalent is calculated on the basis of heat value equivalent.
| 2022-01-25T08:59:00 |
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|
https://par.nsf.gov/biblio/10278882-unravelling-physics-multiphase-agn-winds-through-emission-line-tracers
|
Unravelling the physics of multiphase AGN winds through emission line tracers
ABSTRACT Observations of emission lines in active galactic nuclei (AGNs) often find fast (∼1000 km s−1) outflows extending to kiloparsec scales, seen in ionized, neutral atomic and molecular gas. In this work we present radiative transfer calculations of emission lines in hydrodynamic simulations of AGN outflows driven by a hot wind bubble, including non-equilibrium chemistry, to explore how these lines trace the physical properties of the multiphase outflow. We find that the hot bubble compresses the line-emitting gas, resulting in higher pressures than in the ambient interstellar medium or that would be produced by the AGN radiation pressure. This implies that observed emission line ratios such as [O iv]$_{25 \, \rm {\mu m}}$ / [Ne ii]$_{12 \, \rm {\mu m}}$, [Ne v]$_{14 \, \rm {\mu m}}$ / [Ne ii]$_{12 \, \rm {\mu m}}$, and [N iii]$_{57 \, \rm {\mu m}}$ / [N ii]$_{122 \, \rm {\mu m}}$ constrain the presence of the bubble and hence the outflow driving mechanism. However, the line-emitting gas is under-pressurized compared to the hot bubble itself, and much of the line emission arises from gas that is out of pressure, thermal and/or chemical equilibrium. Our results thus suggest that assuming equilibrium conditions, as commonly done in AGN line emission models, is not justified more »
Authors:
; ;
Award ID(s):
Publication Date:
NSF-PAR ID:
10278882
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
503
Issue:
2
Page Range or eLocation-ID:
1568 to 1585
ISSN:
0035-8711
National Science Foundation
More Like this
1. ABSTRACT
We study the gas distribution and kinematics of the inner kpc of six moderately luminous (43.43 ≤ log Lbol ≤ 44.83) nearby (0.004 ≤ z ≤ 0.014) Seyfert galaxies observed with the Near-infrared Integral Field Spectrograph (NIFS) in the J ($1.25\,\mu$m) and K ($2.2\,\mu$m) bands. We analyse the most intense emission lines detected on these spectral wavebands: [Fe ii] $1.2570\, \mu$m and Paβ, which trace the ionized gas in the partially and fully ionized regions, and $\mathrm{ H}_2 \ 2.1218\, \mu$m, which traces the hot (∼2000 K) molecular gas. The dominant kinematic component is rotation in the disc of the galaxies, except for the ionized gas in NGC 5899 that shows only weak signatures of a disc component. We find ionized gas outflow in four galaxies, while signatures of H2 outflows are seen in three galaxies. The ionized gas outflows display velocities of a few hundred km s−1, and their mass outflow rates are in the range 0.005–12.49 M⊙ yr−1. Their kinetic powers correspond to 0.005–0.7 per cent of the active galactic nuclei (AGN) bolometric luminosities. Besides rotation and outflows signatures in some cases, the H2 kinematics also reveals inflows in three galaxies. The inflow velocities are 50–80 km s−1 and the mass inflow rates are in the range 1–9 × 10−4 M⊙ yr−1 formore »
2. ABSTRACT
Interstellar chemistry is important for galaxy formation, as it determines the rate at which gas can cool, and enables us to make predictions for observable spectroscopic lines from ions and molecules. We explore two central aspects of modelling the chemistry of the interstellar medium (ISM): (1) the effects of local stellar radiation, which ionizes and heats the gas, and (2) the depletion of metals on to dust grains, which reduces the abundance of metals in the gas phase. We run high-resolution (400 M⊙ per baryonic particle) simulations of isolated disc galaxies, from dwarfs to Milky Way-mass, using the fire galaxy formation models together with the chimes non-equilibrium chemistry and cooling module. In our fiducial model, we couple the chemistry to the stellar fluxes calculated from star particles using an approximate radiative transfer scheme; and we implement an empirical density-dependent prescription for metal depletion. For comparison, we also run simulations with a spatially uniform radiation field, and without metal depletion. Our fiducial model broadly reproduces observed trends in H i and H2 mass with stellar mass, and in line luminosity versus star formation rate for [C ii]$_{158 \rm {\mu m}}$, [O i]$_{63 \rm {\mu m}}$, [O iii]$_{88 \rm {\mu m}}$, [N ii]$_{122 \rm {\mu m}}$, andmore »
3. Abstract
We study the ionization and excitation structure of the interstellar medium in the late-stage gas-rich galaxy merger NGC 6240 using a suite of emission-line maps at ∼25 pc resolution from the Hubble Space Telescope, Keck/NIRC2 with Adaptive Optics, and the Atacama Large Millimeter/submillimeter Array (ALMA). NGC 6240 hosts a superwind driven by intense star formation and/or one or both of two active nuclei; the outflows produce bubbles and filaments seen in shock tracers from warm molecular gas (H22.12μm) to optical ionized gas ([Oiii], [Nii], [Sii], and [Oi]) and hot plasma (FeXXV). In the most distinct bubble, we see a clear shock front traced by high [Oiii]/Hβand [Oiii]/[Oi]. Cool molecular gas (CO(2−1)) is only present near the base of the bubble, toward the nuclei launching the outflow. We interpret the lack of molecular gas outside the bubble to mean that the shock front is not responsible for dissociating molecular gas, and conclude that the molecular clouds are partly shielded and either entrained briefly in the outflow, or left undisturbed while the hot wind flows around them. Elsewhere in the galaxy, shock-excited H2extends at least ∼4 kpc from the nuclei, tracing molecular gas even warmer than that between the nuclei, wheremore »
4. ABSTRACT
We present a detailed analysis of the ionized gas distribution and kinematics in the inner ∼ 200 pc of NGC 4546, host of a low-luminosity active galactic nucleus (LLAGN). Using GMOS−IFU observations, with a spectral coverage of 4736–6806 Å and an angular resolution of 0.7 arcsec, we confirm that the nuclear emission is consistent with photoionization by an AGN, while the gas in the circumnuclear region may be ionized by hot low-mass evolved stars. The gas kinematics in the central region of NGC 4546 presents three components: (i) a disc with major axis oriented along a position angle of 43° ± 3°, counter rotating relative to the stellar disc; (ii) non-circular motions, evidenced by residual velocities of up to 60 km s−1, likely associated with a previous capture of a dwarf satellite by NGC 4546; and (iii) nuclear outflows in ionized gas, identified as a broad component (σ ∼ 320 km s−1) in the line profiles, with a mass outflow rate of $\dot{M}_{\rm out} = 0.3 \pm 0.1$ M⊙ yr−1 and a total mass of Mout = (9.2 ± 0.8) × 103 M⊙ in ionized gas, corresponding to less than 3 per cent of the total mass of ionized gas in the inner 200 pc of NGC 4546. The kinetic efficiency of themore »
5. Abstract
We present results on the nature of extreme ejective feedback episodes and the physical conditions of a population of massive (M*∼ 1011M), compact starburst galaxies atz= 0.4–0.7. We use data from Keck/NIRSPEC, SDSS, Gemini/GMOS, MMT, and Magellan/MagE to measure rest-frame optical and near-IR spectra of 14 starburst galaxies with extremely high star formation rate surface densities (mean ΣSFR∼ 2000Myr−1kpc−2) and powerful galactic outflows (maximum speedsv98∼ 1000–3000 km s−1). Our unique data set includes an ensemble of both emission ([Oii]λλ3726,3729, Hβ, [Oiii]λλ4959,5007, Hα, [Nii]λλ6549,6585, and [Sii]λλ6716,6731) and absorption (Mgiiλλ2796,2803, and Feiiλ2586) lines that allow us to investigate the kinematics of the cool gas phase (T∼ 104K) in the outflows. Employing a suite of line ratio diagnostic diagrams, we find that the central starbursts are characterized by high electron densities (medianne∼ 530 cm−3), and high metallicity (solar or supersolar). We show that the outflows are most likely driven by stellar feedback emerging from the extreme central starburst, rather than by an AGN. We also present multiple intriguing observational signatures suggesting that these galaxies may have substantial Lyman continuum (LyC) photon leakage, including weak [Sii]nebular emission lines. Our results imply that these galaxies may be captured in a short-lived phase of extrememore »
| 2022-12-05T11:45:12 |
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https://pos.sissa.it/334/089/
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Volume 334 - The 36th Annual International Symposium on Lattice Field Theory (LATTICE2018) - Hadron Spectroscopy and Interactions
Towards the P-wave nucleon-pion scattering amplitude in the $\Delta$ (1232) channel
S. Paul,* G. Silvi, C. Alexandrou, G. Koutsou, S. Krieg, L. Leskovec, S. Meinel, J. Negele, M. Petschlies, A. Pochinsky, G. Rendon, S. Syritsyn
*corresponding author
Full text: pdf
Published on: 2019 May 29
Abstract
We use lattice QCD and the L\"uscher method to study elastic pion-nucleon scattering in the isospin $I = 3/2$ channel, which couples to the $\Delta(1232)$ resonance. Our $N_f=2+1$ flavor lattice setup features a pion mass of $m_\pi \approx 250$ MeV, such that the strong decay channel $\Delta \rightarrow \pi N$ is close to the threshold. We present our method for constructing the required lattice correlation functions from single- and two-hadron interpolating fields and their projection to irreducible representations of the relevant symmetry group of the lattice. We show preliminary results for the energy spectra in selected moving frames and irreducible representations, and extract the scattering phase shifts. Using a Breit-Wigner fit, we also determine the resonance mass $m_\Delta$ and the $g_{\Delta-\pi N}$ coupling.
DOI: https://doi.org/10.22323/1.334.0089
Open Access
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
| 2020-06-06T15:23:40 |
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https://zbmath.org/authors/viazovska.maryna-s
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## Viazovska, Maryna S.
Compute Distance To:
Author ID: viazovska.maryna-s Published as: Viazovska, Maryna; Viazovska, Maryna S.; Vyazovskaya, M. S.; Vyazovs’ka, M. S. more...less Further Spellings: V”yazovs’ka, Maryna Sergiïvna; Вязовская М С; Вязовская Марина Сергеевна; В’язовська Марина Сергіївна Homepage: https://people.epfl.ch/maryna.viazovska External Links: MGP · ORCID · Wikidata · Google Scholar · ResearchGate · Math-Net.Ru · dblp · GND Awards: Clay Research Award (2017) · New Horizons in Mathematics Prize (2018) · EMS Prize (2020) · Fields Medal (2022)
Documents Indexed: 16 Publications since 2005 1 Contribution as Editor Biographic References: 2 Publications Co-Authors: 13 Co-Authors with 11 Joint Publications 326 Co-Co-Authors
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### Co-Authors
6 single-authored 6 Bondarenko, Andriy V. 5 Radchenko, Danylo V. 1 Blomer, Valentin 1 Bringmann, Kathrin 1 Cohn, Henry Lee 1 Kane, Ben 1 Kowalski, Emmanuel 1 Kumar, Abhinav 1 Mellit, Anton S. 1 Michel, Philippe Gabriel 1 Miller, Stephen D. 1 Prymak, Andriy V. 1 Pupashenko, N. S.
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### Serials
3 Annals of Mathematics. Second Series 1 Mathematical Notes 1 Ukraïns’kyĭ Matematychnyĭ Zhurnal 1 Publications Mathématiques 1 Journal of Approximation Theory 1 Journal für die Reine und Angewandte Mathematik 1 Constructive Approximation 1 SIAM Journal on Discrete Mathematics 1 Mathematical Research Letters 1 East Journal on Approximations 1 Oberwolfach Reports 1 European Mathematical Society Magazine
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### Fields
7 Number theory (11-XX) 6 Combinatorics (05-XX) 5 Convex and discrete geometry (52-XX) 4 Approximations and expansions (41-XX) 3 Harmonic analysis on Euclidean spaces (42-XX) 1 General and overarching topics; collections (00-XX) 1 Topological groups, Lie groups (22-XX) 1 Real functions (26-XX) 1 Functional analysis (46-XX)
### Citations contained in zbMATH Open
11 Publications have been cited 263 times in 164 Documents Cited by Year
The sphere packing problem in dimension 8. Zbl 1373.52025
Viazovska, Maryna S.
2017
The sphere packing problem in dimension $$24$$. Zbl 1370.52037
Cohn, Henry; Kumar, Abhinav; Miller, Stephen D.; Radchenko, Danylo; Viazovska, Maryna
2017
Optimal asymptotic bounds for spherical designs. Zbl 1270.05026
Bondarenko, Andriy; Radchenko, Danylo; Viazovska, Maryna
2013
Well-separated spherical designs. Zbl 1314.52020
Bondarenko, Andriy; Radchenko, Danylo; Viazovska, Maryna
2015
Fourier interpolation on the real line. Zbl 1455.11075
2019
Theta lifts and local Maass forms. Zbl 1296.11036
Bringmann, Kathrin; Kane, Ben; Viazovska, Maryna
2013
Spherical designs via Brouwer fixed point theorem. Zbl 1229.05057
Bondarenko, Andriy V.; Viazovska, Maryna S.
2010
CM values of higher Green’s functions and regularized Petersson products. Zbl 1356.11033
Viazovska, Maryna
2015
New asymptotic estimates for spherical designs. Zbl 1170.05013
Bondarenko, Andriy V.; Viazovska, Maryna S.
2008
Petersson inner products of weight-one modular forms. Zbl 1459.11109
Viazovska, Maryna
2019
Sharp sphere packings. Zbl 1447.52021
Viazovska, Maryna
2018
Fourier interpolation on the real line. Zbl 1455.11075
2019
Petersson inner products of weight-one modular forms. Zbl 1459.11109
Viazovska, Maryna
2019
Sharp sphere packings. Zbl 1447.52021
Viazovska, Maryna
2018
The sphere packing problem in dimension 8. Zbl 1373.52025
Viazovska, Maryna S.
2017
The sphere packing problem in dimension $$24$$. Zbl 1370.52037
Cohn, Henry; Kumar, Abhinav; Miller, Stephen D.; Radchenko, Danylo; Viazovska, Maryna
2017
Well-separated spherical designs. Zbl 1314.52020
Bondarenko, Andriy; Radchenko, Danylo; Viazovska, Maryna
2015
CM values of higher Green’s functions and regularized Petersson products. Zbl 1356.11033
Viazovska, Maryna
2015
Optimal asymptotic bounds for spherical designs. Zbl 1270.05026
Bondarenko, Andriy; Radchenko, Danylo; Viazovska, Maryna
2013
Theta lifts and local Maass forms. Zbl 1296.11036
Bringmann, Kathrin; Kane, Ben; Viazovska, Maryna
2013
Spherical designs via Brouwer fixed point theorem. Zbl 1229.05057
Bondarenko, Andriy V.; Viazovska, Maryna S.
2010
New asymptotic estimates for spherical designs. Zbl 1170.05013
Bondarenko, Andriy V.; Viazovska, Maryna S.
2008
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### Cited by 239 Authors
7 Bétermin, Laurent 7 Gorbachëv, Dmitriĭ Viktorovich 6 Brauchart, Johann S. 6 Dai, Feng 6 Steinerberger, Stefan 5 Ehler, Martin 5 Grabner, Peter J. 5 Schwagenscheidt, Markus 5 Womersley, Robert S. 4 Bringmann, Kathrin 4 Cohn, Henry Lee 4 Gonçalves, Felipe M. 4 Gräf, Manuel 4 Ivanov, Valerĭ Ivanovich 4 Radchenko, Danylo V. 4 Saff, Edward Barry 4 Tikhonov, Sergey Yur’evich 4 Viazovska, Maryna S. 3 Alfes-Neumann, Claudia 3 Bannai, Eiichi 3 Boĭvalenkov, Pet”r Georgiev 3 de Laat, David 3 Dick, Josef 3 Etayo, Ujué 3 Faulhuber, Markus 3 Hardin, Douglas P. 3 Lev, Nir 3 Li, Yingkun 3 Mazáč, Dalimil 3 Petrache, Mircea 3 Stepanyuk, Tetiana A. 3 Wang, Yuguang 2 Bilyk, Dmitry 2 Bondarenko, Andriy V. 2 Breger, Anna 2 Carmelo Interlando, J. 2 Chen, Xiaojun 2 da Nóbrega Neto, Trajano Pires 2 Dantas Lopes, José Othon 2 de Oliveira Filho, Fernando Mário 2 Fernique, Thomas 2 Gaál, Marcell 2 Gariboldi, Bianca 2 Gigante, Giacomo 2 Hartman, Thomas E. 2 Kallus, Yoav 2 Kane, Ben 2 Knüpfer, Hans 2 Kuperberg, Gregory John 2 Leopardi, Paul Charles 2 Lopes Nunes, José Valter 2 Lu, Jianfeng 2 Okuda, Takayuki 2 Peled, Ron 2 Peter, Thomas 2 Ramos, João P. G. 2 Rastelli, Leonardo 2 Reti, Gilad 2 Sloan, Ian Hugh 2 Smirnov, Oleg Igorevich 2 Stoyanova, Maya M. 2 Vallentin, Frank 2 Xiang, Ziqing 2 Yu, Wei-Hsuan 2 Zhou, Yang 1 Afkhami-Jeddi, Nima 1 Aistleitner, Christoph 1 Amato, Daniela A. 1 An, Congpei 1 Andreanov, Alexei 1 Ash, Avner 1 Avigad, Jeremy 1 Babecki, Catherine 1 Bachoc, Christine 1 Bannai, Etsuko 1 Beltrán, Carlos 1 Berman, Robert J. 1 Björner, Anders 1 Bourne, David P. 1 Brandolini, Luca 1 Bremer, Peer-Timo 1 Briol, François-Xavier 1 Bruinier, Jan Hendrik 1 Buhmann, Martin Dietrich 1 Carneiro, Emanuel 1 Castillo, Ignacio 1 Cherlin, Gregory L. 1 Chirre, Andrés 1 Choksi, Rustum 1 Corral, Nuria 1 Criado del Rey, Juan G. 1 Cristoferi, Riccardo 1 Cui, Zhen 1 Darmon, Henri René 1 De Courcy-Ireland, Matthew 1 De Luca, Lucia 1 Deblois, Jason 1 DeCorte, Evan 1 Delchev, Konstantin 1 Dixon, Geoffrey M. ...and 139 more Authors
all top 5
### Cited in 93 Serials
9 Advances in Mathematics 8 Discrete & Computational Geometry 6 Journal of Approximation Theory 6 Transactions of the American Mathematical Society 6 Journal of High Energy Physics 5 Journal of Complexity 4 Constructive Approximation 3 Communications in Mathematical Physics 3 Mathematics of Computation 3 Mathematische Annalen 3 Bulletin of the American Mathematical Society. New Series 3 The Journal of Fourier Analysis and Applications 2 Archive for Rational Mechanics and Analysis 2 Israel Journal of Mathematics 2 Journal d’Analyse Mathématique 2 Journal of Mathematical Analysis and Applications 2 Journal of Statistical Physics 2 Rocky Mountain Journal of Mathematics 2 Duke Mathematical Journal 2 Inventiones Mathematicae 2 Mathematische Zeitschrift 2 Mathematika 2 Linear Algebra and its Applications 2 SIAM Journal on Mathematical Analysis 2 Experimental Mathematics 2 Applied and Computational Harmonic Analysis 2 Advances in Computational Mathematics 2 Foundations of Computational Mathematics 2 Journal of Algebra and its Applications 1 Analysis Mathematica 1 Bulletin of the Australian Mathematical Society 1 Computer Methods in Applied Mechanics and Engineering 1 Journal of Mathematical Physics 1 Letters in Mathematical Physics 1 Mathematical Notes 1 Mathematical Proceedings of the Cambridge Philosophical Society 1 Physics Reports 1 Ukrainian Mathematical Journal 1 Abhandlungen aus dem Mathematischen Seminar der Universität Hamburg 1 Applied Mathematics and Computation 1 Archiv der Mathematik 1 Commentarii Mathematici Helvetici 1 Compositio Mathematica 1 Publications Mathématiques 1 Journal of Functional Analysis 1 Journal of Pure and Applied Algebra 1 Mathematics of Operations Research 1 Monatshefte für Mathematik 1 Numerische Mathematik 1 Proceedings of the American Mathematical Society 1 Results in Mathematics 1 SIAM Journal on Computing 1 SIAM Journal on Numerical Analysis 1 Acta Mathematica Hungarica 1 Applied Numerical Mathematics 1 Graphs and Combinatorics 1 Statistical Science 1 Revista Matemática Iberoamericana 1 The Journal of Geometric Analysis 1 Designs, Codes and Cryptography 1 M$$^3$$AS. Mathematical Models & Methods in Applied Sciences 1 Numerical Algorithms 1 Geometric and Functional Analysis. GAFA 1 SIAM Journal on Applied Mathematics 1 Mathematical Programming. Series A. Series B 1 Calculus of Variations and Partial Differential Equations 1 Combinatorics, Probability and Computing 1 Advances in Applied Clifford Algebras 1 Bulletin des Sciences Mathématiques 1 Sbornik: Mathematics 1 Izvestiya: Mathematics 1 Annals of Mathematics. Second Series 1 Interdisciplinary Information Sciences (IIS) 1 Communications in Contemporary Mathematics 1 Journal of Mathematical Logic 1 Annales Henri Poincaré 1 Journal of Machine Learning Research (JMLR) 1 Mediterranean Journal of Mathematics 1 Foundations of Physics 1 Mathematical Biosciences and Engineering 1 International Journal of Number Theory 1 Chebyshevskiĭ Sbornik 1 Optimization Letters 1 SIAM Journal on Imaging Sciences 1 Journal of Topology and Analysis 1 Analysis and Mathematical Physics 1 Forum of Mathematics, Sigma 1 Annales de l’Institut Henri Poincaré D. Combinatorics, Physics and their Interactions (AIHPD) 1 Waves, Wavelets and Fractals. Advanced Analysis 1 Discrete Analysis 1 Algebraic Combinatorics 1 Japanese Journal of Statistics and Data Science 1 European Mathematical Society Magazine
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### Cited in 45 Fields
42 Number theory (11-XX) 39 Convex and discrete geometry (52-XX) 29 Numerical analysis (65-XX) 27 Combinatorics (05-XX) 27 Approximations and expansions (41-XX) 26 Harmonic analysis on Euclidean spaces (42-XX) 20 Operations research, mathematical programming (90-XX) 15 Statistical mechanics, structure of matter (82-XX) 10 Functional analysis (46-XX) 9 Quantum theory (81-XX) 8 Special functions (33-XX) 8 Computer science (68-XX) 8 Mechanics of deformable solids (74-XX) 8 Information and communication theory, circuits (94-XX) 7 Calculus of variations and optimal control; optimization (49-XX) 6 Partial differential equations (35-XX) 6 Global analysis, analysis on manifolds (58-XX) 6 Statistics (62-XX) 5 Measure and integration (28-XX) 5 Potential theory (31-XX) 5 Probability theory and stochastic processes (60-XX) 4 Nonassociative rings and algebras (17-XX) 4 Real functions (26-XX) 4 Functions of a complex variable (30-XX) 4 Ordinary differential equations (34-XX) 2 History and biography (01-XX) 2 Algebraic geometry (14-XX) 2 Group theory and generalizations (20-XX) 2 Dynamical systems and ergodic theory (37-XX) 2 Abstract harmonic analysis (43-XX) 2 Geometry (51-XX) 2 Differential geometry (53-XX) 2 Relativity and gravitational theory (83-XX) 1 General and overarching topics; collections (00-XX) 1 Mathematical logic and foundations (03-XX) 1 Linear and multilinear algebra; matrix theory (15-XX) 1 Associative rings and algebras (16-XX) 1 Topological groups, Lie groups (22-XX) 1 Sequences, series, summability (40-XX) 1 Integral transforms, operational calculus (44-XX) 1 General topology (54-XX) 1 Manifolds and cell complexes (57-XX) 1 Fluid mechanics (76-XX) 1 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 1 Biology and other natural sciences (92-XX)
### Wikidata Timeline
The data are displayed as stored in Wikidata under a Creative Commons CC0 License. Updates and corrections should be made in Wikidata.
| 2022-08-09T04:36:47 |
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https://pokemon.fandom.com/wiki/User_talk:Energy_X/Archive_4
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## FANDOM
17,646 Pages
Witch character images in particular? Marioandluigibros12345 (talk) 15:51, January 6, 2014 (UTC)
You already deleted the picture. Thank you Animespace (talk) 16:54, February 10, 2014 (UTC)
## Shard question
Do you want me to place that link on the talk page just so people don't start trying to argue about it, or would directing them to your archive 3 page suffice? Shardsilver (talk) 20:57, January 6, 2014 (UTC)
Would you please show how can I remove pictures which I uploaded by mistake? Animespace (talk) 15:30, February 10, 2014 (UTC)
## Report on Kaneandbigshow2 (Talk Page removal)
King Marth 64 – (other wikis • blogs) - At first. There are Shadow Dragon, Falchion Sword, and Fire Emblem: Shadow Dragon.TALK – Time Right Now: Thursday, 13 August 2020, 09:15. This was signed at: 01:28, January 7, 2014 (UTC). I am reporting on that Kaneandbigshow2 was removing your comment from his talk page and I just undid Shardsilver's edit that he did undo that edit that I reverted Kaneandbigshow2's edit earlier.
From what I understand, blanking talk pages is fine here, right?
I noticed someone doing it before and they assured me it was ok here for some reason. ƒelinoel ~ (Talk) 01:41, January 7, 2014 (UTC)
If it is your talk page, you can remove what you want. If you see someone revert a user who is removing comments off their own talk page, report that person, because they're not suppose to nor do they have the right. Shardsilver (talk) 01:44, January 7, 2014 (UTC)
Wait... so if it is your talk page you can remove whatever you want? ƒelinoel ~ (Talk) 01:52, January 7, 2014 (UTC)
Of course (unless you were blocked and a mod then takes away your ability to edit your talk page-some will take away your ability to edit your talk page when blocked depending on the circumstance of the block). Shardsilver (talk) 01:59, January 7, 2014 (UTC)
As far as I know, one can't remove anything from his talk page.He can archive them but removal is not allowed.--Monfernape_If any problem? 09:35, January 7, 2014 (UTC)
No, you can (it's your talk page, thus it's your right what stays and what doesn't). See the policy about it. Shardsilver (talk) 12:19, January 7, 2014 (UTC)
Offensive messages and spam would be deemed acceptable to be removed from your talk page. But any other message can only be removed from your talk page if it is archived off onto a subpage of you talk page. RainbowShifter 16:55, January 7, 2014 (UTC)
You need to read it, because it says you're free to still remove comments off your page even if archiving is preffered. I even have it (and other things you need to read) quoted on your talk page. Shardsilver (talk) 21:42, January 7, 2014 (UTC)
Well what I was talking about wasn't a User page, but an actual article's talk page. Someone was blanking it and told me it was allowed when I questioned it. ƒelinoel ~ (Talk) 05:24, January 8, 2014 (UTC)
## Re: Edits
Hello. I was on vacation, so I wasn't able to edit during that time. Now that I am back home, I will be getting used to normal life again and return :-) 18:52, January 7, 2014 (UTC)
Yeah I am interested, but I can't do this right now. I will try my best to edit periodically. 21:31, January 7, 2014 (UTC)
Couldn't one assemble a bot to do this?
Not me sadly, but someone who knows programming could get that done. ƒelinoel ~ (Talk) 05:07, January 8, 2014 (UTC)
It could indeed, do you want me to find someone who can make a bot for that? ƒelinoel ~ (Talk) 00:49, January 9, 2014 (UTC)
## Gallery Box
I saw my edits reverted, so I thought it would be best to capture the mistake.So I am here.I want to ask that is it not allowed to use Gallery Box Small templated other than episode pages? If not then I am sorry for my recent edits. I shall take care of this in future.--Monfernape_If any problem? 19:18, January 7, 2014 (UTC)
## Sorry
I'm sorry. But why does everyone hate me over my talk page, I'm not bad..... =( Kaneandbigshow2 (talk) 22:38, January 7, 2014 (UTC)
I little mistake I made. I was making category of X and Y images but I wrote XY anime images. I didn't intend to do this.Please fix it and make it category.--Monfernape_If any problem? 17:14, January 8, 2014 (UTC)
Oh! I'm sorry. Next time it will have proper caption. Animespace (talk) 12:01, January 23, 2014 (UTC)
## Renaming Image
Hi there, can you please show me how to rename an image please? —Preceding unsigned comment added by DragonSpore18 (talkcontribs)
Thanks for the info on characterizing the image, but the problem is I can't figure out how to convert the Pokémon png image into a jpg image. —Preceding unsigned comment added by DragonSpore18 (talkcontribs)
## XY Images
You asked about the XY images.In your previous archive, I have told you that I would try to upload the XY images as soon as possible to save ourselves with burden of images altogether. But if there's any problem I can stop it.--Monfernape_If any problem? 19:06, January 9, 2014 (UTC)
Hi Energy X, I was wondering if i could edit your profile page so it is more appealing to users and reorganise so it looks neater. Ellis99 (talk) 20:59, January 9, 2014 (UTC)Ellis99
## Rayquaza
What summary box?--Kyurem147 (talk) 10:53, January 10, 2014 (UTC)
No I really need recreate it!. Dragonspore ask me if I'm going recreate a better one and I say yes. Ask her for her opinon. Consider it a vouch.--Kyurem147 (talk) 11:01, January 10, 2014 (UTC)
Please trust me on this. I'm not bad as you think I am.--Kyurem147 (talk) 11:02, January 10, 2014 (UTC)
This is way more personal. This my favorite pokemon We're talking about. Please understand, do me just this one favor. I've never asked you this before and it's only one time. I really need this!.--Kyurem147 (talk) 11:11, January 10, 2014 (UTC)
You still don't get it. I really need to recreate the article! I can make it like new. We don't know each other very well, but please understand this my favorite pokemon. You've got to do me this one favor. I'll come up with a payback. --Kyurem147 (talk) 11:22, January 10, 2014 (UTC)
It's a deal. I promise.--Kyurem147 (talk) 00:01, January 11, 2014 (UTC)
Thank you so much! but just one thing why'd you change Jeanette take my pic out of the box?--Kyurem147 (talk) 00:34, January 11, 2014 (UTC)
What are you talking about you and dragonspore did the same thing.--Kyurem147 (talk) 00:39, January 11, 2014 (UTC)
Ok ok ok lets not hasty! How can I copy it without it looking similar?--Kyurem147 (talk) 00:44, January 11, 2014 (UTC)
## Serena
Why did you take out the part about Serena liking Ash? I gave you a link that proved it (in your recent archive). Shardsilver (talk) 02:49, January 11, 2014 (UTC)
Placed proof on talk page. It's on page 353 near the bottom in the source I gave. If possible, perhaps you could get that table and upload it to Serena's gallary (if you want). Shardsilver (talk) 14:21, January 11, 2014 (UTC)
As far as I know, that table was official. Usually people get stuff like that from a very credible source or from the writer, and they post in forums so people can see it. If that table does turn out to be fake, I'll let you know, but as far as I can see it's not Shardsilver (talk) 15:22, January 11, 2014 (UTC)
It was the best place to me, since they have shown official japanese magazine things. Albiet I didn't like using a rival site to do it, but times call for measures. In any case, I will keep looking just to ensure that japanese table isn't fake. Shardsilver (talk) 15:31, January 11, 2014 (UTC)
## Hello
My name is TheUltraman, I'm the head admin and runner of the Super Smash Bros Wiki (http://supersmashbros.wikia.com). Recently our wiki has become partners with the Mario Wiki (http://mario.wikia.com), I have contacted you and the two other active admins here asking if you're wiki would like to become partners with ours aswell. Pokemon is one of Nintendos biggest franchise's and because of that they have had alot of apperances in Smash. If you would like to accept my offer post below and we can make an announcement on both wiki's. If you decline I understand.
Thanks for taking the time to read my announcement. TheUltraman (talk) 20:04, January 11, 2014 (UTC)
## Re: Main Page
The FamilyTree template looks terrible altogether but theres nowhere else we could put it. RainbowShifter 21:15, January 11, 2014 (UTC)
Nevermind, I see your recent edit to it. RainbowShifter 21:15, January 11, 2014 (UTC)
## Generation <#> Pokémon artworks
You're saying I've got to add this [[Generation <#> Pokémon artworks]]? Same for those others I put?--Kyurem147 (talk) 01:31, January 12, 2014 (UTC)
## Artwork
You lost at this-The difference is that the first inserts a category, while the second to an article that does not exist. Also when I add that catergory I have to put this <#>? --Kyurem147 (talk) 14:13, January 12, 2014 (UTC)
## Affiliates
Hello, my name is Dreb607 and I would like to ask the same thing Ultraman is asking. Would you like to becomer partners with the following wikis:
## Delete
You tell me not to blank a page. So I just put delete on it and then what?--Kyurem147 (talk) 22:59, January 12, 2014 (UTC)
It has to be a good reason right? What would be a good reason?--Kyurem147 (talk) 23:15, January 12, 2014 (UTC)
Fixed it.--Kyurem147 (talk) 18:53, January 13, 2014 (UTC)
Fine, I'll put a reason, but if I do and you say no. You'll see why I don't put reasons because they never agreeable.--Kyurem147 (talk) 20:25, January 15, 2014 (UTC)
There, I put reasonable reasons. If they're not right can tell me about the existing so I can put the right one. I'm like working hard in these.--Kyurem147 (talk) 20:43, January 15, 2014 (UTC)
Please I know there is a reason I just didn't put the right one. That's way I need to know the other existing ones. Just let me ask you this. Why'd you delete the Rayquaza (MS007) page when I asked you to.--Kyurem147 (talk) 21:47, January 15, 2014 (UTC)
Oh, right. Ok I'll tell you my reason, but I'll say it simply. I wanted to recreate that page because it was favorite pokemon right? Well like rayquaza and I don't usually/always do this, but they're certain pokemon pages with a certain pokemon I want to create. I think I told this and you given the solution, but it's not enough. See regular pages are like history, they're seen by all. A sandbox is private (sort of). Call it an urge. I've told dragonspore and no she's an ADMIN, but she understands. I've got an personal acquaintance of mine who knows me.--Kyurem147 (talk) 22:03, January 15, 2014 (UTC)
Hey, ok that's just harsh! Ok urge was so the wrong word, but you're wrong the others. I'm saying not this is my site and I'm not demanding I'm asking like I did with rayquaza. persistent yes, but still asked. I said I don't always do this. I'm not bad and I'm not trying make enemies with spore (or you for that matter). Also to answer this Plus, how would I know that your article does not have something that the former had. I can put more bio info but only you tell me how to not make it so copycatty. Try talking to me in a nice way. --Kyurem147 (talk) 22:19, January 15, 2014 (UTC)
I keep telling you I'm not demanding, but I get the unexplainable edits part. And what words are you talking about? Also when you asked me this article does not have something that the former had. It was kind of clue. If I tell you and if necessary show you that my page won't same as the last one, could recreate it? If you have to help me then could you please tell me how can I not copy text and how can I legally recreate an article?--Kyurem147 (talk) 23:06, January 15, 2014 (UTC)
Ok We're starting to get on track. You're right an article that is to be deleted may have a portion of info that when deleted. I'm way ahead of you. I don't want the info gone either so I have a safety measure to save the info and put it back on once a page is remade.--Kyurem147 (talk) 23:20, January 15, 2014 (UTC)
You said you were help out with this.--Kyurem147 (talk) 19:36, January 16, 2014 (UTC)
I already told you I have it covered. I copy the info on a word file so we don't lose it!. That's how I did it with Rayquaza (MS007).--Kyurem147 (talk) 19:42, January 16, 2014 (UTC)
I'm talking about the info you're worried about getting deleted.--Kyurem147 (talk) 19:48, January 16, 2014 (UTC)
Hear out me X. You like creating pages it's what you and everybody enjoys, but let me ask this. If their was a certain page you really wanted to and/or was just about to create (like I really wanted to create rayquaza) and someone got in your way. Would you get upset like I am.--Kyurem147 (talk) 20:16, January 16, 2014 (UTC)
Well maybe you can take a loss like that, but for me the scars run deep (VERY DEEP). How is it X? someone else creating the missing pages: How is that you are able to take something that so well. How is it you're able to shake it off and let go?--Kyurem147 (talk) 20:46, January 16, 2014 (UTC)
## Re: Episode plots
I have a lot of episode plots which I wrote back then but never remebered to publish, most of those episodes already have plots now. I hope to be able to rewatch some of the older anime episodes and write more soon. RainbowShifter 16:31, January 13, 2014 (UTC)
## Professor Sycamore's Garchomp
You said put a good reason deletion right? Well I got one.--Kyurem147 (talk) 16:32, January 14, 2014 (UTC)
Sorry 'bout that.
If you could add this, it would help me. I'm currently doing Mega Latias.
Thx.
Waxality is the key (talk) 22:19, January 16, 2014 (UTC)
Oh, still kinda don't know how to do that. He he... kinda just started editing......if you could or
just tell me.
=] thx.
Waxality is the key (talk) 22:54, January 16, 2014 (UTC)
## Ash's Froakie
Ash's Froakie is confirmed as a male because Premier's Sylveon used Attract on him in the episode.
## Re: User of the month
lol really? Thanks then! ƒelinoel ~ (Talk) 06:38, January 17, 2014 (UTC)
## Why
This is Imperial Wyrm. Why did you undo my edit on Ash's Father? I was being accurate...the Rapidash trainer was Ash's father wasn't it? {{SUBST:User:Jadenyuki93/sig}} 20:22, January 17, 2014 (UTC)
## Johnny
What'd you do the page? I worked hard on that.--Kyurem147 (talk) 00:52, January 19, 2014 (UTC)
## Re: FOB
I was thinking Ludicolo versus Shiftry due to their grass type similarities and their move similarities. RainbowShifter 19:24, January 19, 2014 (UTC)
## Legendary Birds (MS002)
Do they need separate character pages?--Kyurem147 (talk) 01:38, January 20, 2014 (UTC)
So I can make character pages of the birds?--Kyurem147 (talk) 16:21, January 20, 2014 (UTC)
## Thoughts?
Forum:No_Fairy_for_Gen_I-V. ƒelinoel ~ (Talk) 02:28, January 20, 2014 (UTC)
Look there was a photo i had up they were all pokemon related and later being taken down?! how were they taken down please reply -MaverickYveltal
## OI018
When the time comes, please upload a bigger version of this pic. Signed, Winxfan1. (I am the ultimate fan of Winx Club) 13:18, January 21, 2014 (UTC)
Well, you are gonna replace it, so why not upload an image exactly like this?
Signed, Winxfan1. (I am the ultimate fan of Winx Club) 21:45, January 21, 2014 (UTC)
I would appreciate that. Thank you.
Signed, Winxfan1. (I am the ultimate fan of Winx Club) 21:50, January 21, 2014 (UTC)
Over at the Adventure Time wiki we have a template for images of poorer than preferred quality, it puts a banner on the image's article explaining that it is requesting that someone uploads a new version of the same image but with better quality, AND it puts it in a category for images of poor quality so that someone who wants to upload images can just check out the category. One could easily copy the template for use here to stop the need for future discussions like this since everyone will already know what needs a better quality version. ƒelinoel ~ (Talk) 18:09, January 22, 2014 (UTC)
## Re: Anime characters
Wait, it shoukd actually be "Biography" per the Layout Guide. RainbowShifter 20:18, January 23, 2014 (UTC)
## Manga Images
I would like to clarify that I don't remember uploading any manga images and if I did it is from the Pokemon Adventures Manga Wiki.Ellis99 (talk) 16:24, January 24, 2014 (UTC)Ellis99 (Underlined for the site.)
## Yes!
Yes, I think thats possible, but I would like someone to contribute with me too.Ellis99 (talk) 19:43, January 24, 2014 (UTC)Ellis99
## Lorelei
If I wanted a page about one of prima's pokemon, is it Prima's or Lorelei's?--Kyurem147 (talk) 03:00, January 25, 2014 (UTC)
So I wanted to create her Dewgong, it should be prima's Dewgong because there's Lorelei's Dewgong.--Kyurem147 (talk) 16:57, January 25, 2014 (UTC)
What Pokémon: Advanced Generation Series images?--Kyurem147 (talk) 01:40, January 26, 2014 (UTC)
## Message
I'm sorry sorry, I was tring to make a fan fiction on Pokemon Fanon wiki when the editing ended up on this wikia.-Dino-drones (talk)
## RE:TCG
Yeah that will work~
Slay Talk "Shadows wonder why we scream."01:07,1/26/2014 4,527
## Pokédex Entry Errors
Hi I just wanted to let you know that while I was editing some pages I came across some black and white 2 entries. Some people edit the pokedex entries as "black2" and "white2" instead of making a space between the words like (black 2) and (white 2). This causes the pokedex entry to not show up. I have edited the ones I have seen and it seems to be occouring frequently. JPace8921 (talk) 11:33, January 26, 2014 (UTC)
## Manga
Thanks, I have the Pokemon Adventure books upto the Gold/Silver Arc.Ellis99 (talk) 14:02, January 26, 2014 (UTC)Ellis99
## Template:Starter
Hi there, I was wondering if I could edit the the template, but somehow I can't, could you help please.Ellis99 (talk) 19:00, January 26, 2014 (UTC)Ellis99
## Thanks
Thank you for the template links.Ellis99 (talk) 19:07, January 26, 2014 (UTC)ellis99
## Help
Sorry for asking (again), but do you know who posted the Pokemon xy 3d models, if you could ask them to massage me the site they found them from, it would be a great deal to me. Ellis99 (talk) 19:16, January 26, 2014 (UTC)
## Question
Hi there, I have a question I would like to ask you. Is the anime character, O, from the Sinnoh region or from the Kanto region?
Please lock the pokemon Transporter page as well. In doing so you will stop vandalism.
Arquillius Maximus (talk) 01:04, January 28, 2014 (UTC)
## Manga
Hi there, I will start writing the manga plot on Saturday. Ellis99 (talk) 09:44, January 30, 2014 (UTC)
Hi Jakov,its Rick here i want to work for walkthrough projects how can apply there plus nic meeting you're an amazing user thanks for reading my message.BlazeFire
We should not close the idea of poke power that new users will replace the old ones cause you know they might never come back but still we can re-start the project for te betterment of this wiki.Please can you allow me to put your name in next the featured wikians list. BlazeFire 09:20, January 31, 2014 (UTC)
## Manga
Well, at this moment, I can't scan images through a printer because it's playing up, so I will have to buy a new printer. Ellis99 (talk) 21:08, January 31, 2014 (UTC)
## 2 for 1
1. No, including moves that have debuted would be overkill.
2. I pick Ludicolo and Roselia.
Signed, Winxfan1. (I am the ultimate fan of Winx Club) 22:49, January 31, 2014 (UTC)
1. True, but with the hundreds of moves it would be impossible to put them all in by episode.
2. Okay, ... Roselia vs. okay, what gen 3 grass or poison pokemon have been done before?
Signed, Winxfan1. (I am the ultimate fan of Winx Club) 00:33, February 1, 2014 (UTC)
Uh i wanted to be a part of walkthrough project also plus i am new here thanks mr.admin.Plasma X (talk) 04:41, February 1, 2014 (UTC)
1. Okay, why not, but don't expect me to do this.
2. How about Roselia vs. Cacturne?
Signed, Winxfan1. (I am the ultimate fan of Winx Club) 12:40, February 1, 2014 (UTC)
## Vandalism/Spam
This user is spamming/vandalizing the N page. Can you please help? Thanks. - Healer144 (talk) 06:52, February 1, 2014 (UTC)Healer144
## RE:WALKTHROUGH
Pokémon FireRed/LeafGreen Walkthrough look i will be currently working this!Plasma X (talk) 12:41, February 1, 2014 (UTC)
http://pokemon.wikia.com/wiki/Pok%C3%A9mon_Yellow_Walkthrough This is messed up he had written it whole wrong.Plasma X (talk) 12:52, February 1, 2014 (UTC)
Hey how can i get selected for the featured user please tell me.Plasma X (talk) 12:22, February 2, 2014 (UTC)
Thanks and i get it now but i am nothing compared to you!see ya tommorow. Plasma X (talk) 12:30, February 2, 2014 (UTC)
## Pages to delete, Egg Groups, request, anime character pages
Hi Energy X. There's something I need to tell you. I don't know if you can delete pages, but I want you to take a look at these pages:
These are just some of the pages that need to be deleted. I placed the delete template on Diancia, Hoopa and Volcanion for one reason. Even though I know they're real and someday Game Freak will announce the trio officially along with an event, they haven't been officially confirmed, so I say that we shouldn't have those pages until the event is announced.
Also, you told me to make a cleanup of Generation IV Pokémon and so, I haven't. The reason is that I've noticed that in most Pokémon pages they don't know the Egg Groups the Pokémon belong to, so after I finish with the last pages of Egg Groups, Monster, Fairy and Dragon, I will go and edit. I didn't even know exactly of Pokémon's egg groups so I could place them, but now I do and everybody does.
Besides, I'm aware of my request for rollback, I don't know if you are, but check it. It doesn't bother me, I keep on editing as if anything has happened, but I would like to know what you think about the situation, because I have two support votes, one neutral and two oppose votes.
I also want to tell you that possibly you've noticed a long while ago that I almost abandoned the anime character pages, the reason is that the only seasons I've watched are the Diamond and Pearl saga, the Black and White and the XY in Japanese. So, I don't know about the Original series and Advanced Generation very well, I mean, I've seen a few episodes of them, but I don't know enough about them to edit. Besides there's someone who's already adding and editing the pages I missed, because I couldn't.
I think that's all, and sorry if I took a lot of time making you read all this, and as always, you can count on me with anything. $Adrian$ $Perry GZ$ 21:10, February 3, 2014 (UTC)
## Plasma
I got it Jakov!Thanks,by the way nice profile pic.Plasma X (talk) 09:08, February 4, 2014 (UTC)
## Vandalism or Bad Edits
He/She is doing poor edits like publishing like removing off a punctuation and in the next edits he/she is returning it back to normal this might be that. Plasma X (talk) 09:14, February 4, 2014 (UTC)
Thank you, I'm new to this wiki, but I've edited other sites. I hope I don't mess up again!
## Images
Can you also remind him that what ever image I put up on a Pokémon page does not have to be deleted as well, please. One time I added the Charge Beam move picture to the Marble's Luxray page and he deleted it off for no reason. He even did the same exact thing for the Limone's Blaziken page when I added the picture of it using Flamethrower.
## Generation IV and Next Battle
Yesterday night I finished with all the Egg Groups, and I'm ready to move on. I'm ready to make the navbox for Generation IV Pokémon and as you told me, I'm contacting you. Also, about the Pokémon, I was thinking of the pair of Claydol and Dusclops, it would be interesting, but if there is any problem with those two, please tell me. So, yeah. I'm ready whenever you like.
## At the time
At the time Serebii had the pics up before Filb. So, no. But it did expand. Isn't that good enough?
Signed, Winxfan1. (I am the ultimate fan of Winx Club) 23:07, February 6, 2014 (UTC)
## Unblocked
I'm back in.--Kyurem147 (talk) 21:07, February 7, 2014 (UTC)
Well maybe I wouldn't be delete tagging without reason if you help me by giving a good reason. Besides I said with pictures there some articles I would want to create myself. There will be some I'd want to recreate.--Kyurem147 (talk) 21:24, February 7, 2014 (UTC)
## Ground Pokémon Mystery
Take a look at this: http://pokemon.wikia.com/wiki/Category:Ground_Pok%C3%A9mon.
As you can see, almost every single Pokémon is under the Category of "Ground Pokémon". That category should be used for the Ground-type Pokémon, just as there is a "Grass Pokémon" or "Ghost Pokémon" categories. I can't figure out why that category is in every Pokémon page. I took my time after cleaning Cleffa to check every template to see their categorizations. In each of them, everything looks normal. At first I thought it was from the template "PokéBox", because Ground Pokémon is either the first or second category. For example, with Cleffa is the first, but with Pichu is the second. The order according to the template's page is:
1. Type
2. Type 2 (if it doesn't have it is not placed)
3. Generation and region
4. Single type or Dual type
5. Branched evolution
6. Evolution stage
7. Gender
8. Color
9. Body style
10. Evolutionary line
11. Egg group
And since the very first template in the pages is PokéBox, I thought even stronger it was from PokéBox, but I don't seem to find it. It can't be from Type 2 because Pokémon like Ho-Oh and Giratina, which are dual-typed have also the Ground Pokémon category. I hope you can help me with this situation. As always, thanks. $Adrian$ $Perry GZ$ 20:30, February 8, 2014 (UTC)
Possibly yes. That would be a good idea, they will know what to do. $Adrian$ $Perry GZ$ 20:54, February 8, 2014 (UTC)
Maybe you, because I don't know how to contact them. $Adrian$ $Perry GZ$ 03:21, February 8, 2014 (UTC)
What do you mean by "clean"? Which way can I "clean" the pages? Please give me an example so I can "clean" the others. $Adrian$ $Perry GZ$ 00:32, February 11, 2014 (UTC)
I found the whole reason. When they updated the template, they put things that other users didn't notice. In that was the reason of the Ground Pokémon category. I don't know why or how, but it is in "type", for example: type=Electric
If you only put "Electric", the Ground Pokémon category won't appear. Also, you don't have to write "backcolor" nor "border". Those colors are determined by type, I mean, in "type" and "type 2". It took me a long time to figure it out, but I've finally done it. I still wish I knew exactly why the type template caused it, but doesn't matter now.
Also, possibly all this is what you told me, "clean the PokéBox templates on those pages", but I didn't quite understand, so it had me curious to make a weird experiment with Reshiram (anime), and that led me to finding out the answers. $Adrian$ $Perry GZ$ 00:52, February 12, 2014 (UTC)
## Recreate
I know were at major tension, but please have a heart. Let me recreate on article, this ones special because it's the only owned kind of pokemon known in the anime. There no others. I promise you lose the info, I saved it so I wouldn't forget.--Kyurem147 (talk) 07:20, February 9, 2014 (UTC)
Please don't block me permentley. I'll stop!!! I'm really sorry for making you, Rainbow Shifter, Felinoel and everyone else unhappy. Can you tell them that? I'll undo everything. All I can do is ask for forgiveness, compassion and a conversation so to speak. You're a compassionate guy aren't you? I'm a big pokemon fan and a good one. I swear!! I've got lots of new ideas. I just really need someone who really understands me--Kyurem147 (talk) 08:12, February 9, 2014 (UTC)
Ok the images I can do and deal with, that's easy. Articles are another matter. Remember when I told you there some pages I really wanted to create. I don't tag everyone I see. --Kyurem147 (talk) 16:38, February 9, 2014 (UTC)
This time I ask. Please let me recreate one page, please just one. Vito's Swellow Instead of tagging I'm asking. I'm sure you preferred that.--Kyurem147 (talk) 10:25, February 10, 2014 (UTC)
How am I doing at redeeming myself? I asked before I tagged.--Kyurem147 (talk) 23:27, February 10, 2014 (UTC)
## A Suggestion About Pictures!
Instead of removing perfectly good pictures due to having what you call unacceptable names, it might be better if you rename those pictures with more acceptable names. Jenkins92 (talk) 11:47, February 9, 2014 (UTC)
I do not know the site was my brother and he did not think to tell me
## Project
What project?--Kyurem147 (talk) 23:51, February 10, 2014 (UTC)
## Mystery on a Deserted Island
Hey X you know the Mystery on a Deserted Island!?--Kyurem147 (talk) 01:14, February 12, 2014 (UTC)
## Move infobox bug with fairy
Can you edit MediaWiki:Common.css and add the Fairy color to the list of background colors? Thanks! 20:45, February 12, 2014 (UTC)
Go to the section titled /* Background associated to types */ and paste
.type1-Fairy .ctype {background: #F7DEF7;} right below Poison on another line. That should fix it. 21:26, February 12, 2014 (UTC)
Do you think you could move the Fairy line in between Poison and Unknown? I think the placement causes it to put Unknown first then Fairy, which causes Fairy not to appear. Also, change the hex color to #D962D9. 21:45, February 13, 2014 (UTC)
Found out the problem. Go to MediaWiki:Wikia.css and remove the color list from it. 18:57, February 19, 2014 (UTC)
## Melanie
Hey what's going on?!--Kyurem147 (talk) 23:46, February 12, 2014 (UTC)
Well I personally I think appearances are much better!. Gives it more character. Even you're right, you stole that picture form me! I made that myself with my 2 hands!. I don't like it.--Kyurem147 (talk) 23:51, February 12, 2014 (UTC)
I still say that picture still my creation. If you're so instant appearances and headshots then at least let me reload it.--Kyurem147 (talk) 23:56, February 12, 2014 (UTC)
Sorry, but you didn't let me finish my edits first.--Kyurem147 (talk) 23:48, February 13, 2014 (UTC)
## Videos
Do you think I should put battle video's of team leaders and thier admins, so people who dont have the game get a grasp of what it's like.Ellis99 (talk) 13:33, February 13, 2014 (UTC)
## Use the Template:Seasonbox
You have using the Template:Seasonbox.
Hey Energy,I'm Plasma i saw DragonSpore and Kyurem are adding many articles are they helpful or not?Plasma X (talk) 17:21, February 13, 2014 (UTC)
## Thanks
Thanks for replying, and yeah I'll do that.
Thanks, Jakov for driving me out of confusion.I'll try my level best to add info and improve grammar on that pages.Plasma X ~~ Talk ~~ My Contributions 06:11, February 14, 2014 (UTC)
## Deoxys
Hey ok yes I did blank, but in my defense it was for good reason.--Kyurem147 (talk) 18:53, February 14, 2014 (UTC)
X Please help with this one. Can you please delete Madame X's Malamar? There's no proof of it owned I checked I saw it. http://bulbapedia.bulbagarden.net/wiki/XY019: A Malamar is set to make an appearance in XY019. It antagonizes Ash, his friends and Team Rocket using its powers of hypnosis. This Malamar is specifically referred to as "the most evil Pokémon." Trust me on this one--Kyurem147 (talk) 16:54, February 20, 2014 (UTC)
Thank you. Does that you believed me?--Kyurem147 (talk) 20:52, February 20, 2014 (UTC)
I was thinking about what said:you shouldn't create character pages before the episode is released. What do you think about movie characters. Oh say Xerneas (MS017) That counts right? Should that be deleted?--Kyurem147 (talk) 02:55, February 21, 2014 (UTC)
## Lorelei
Check Lorelei's Cloyster, Lorelei's Jynx, and Lorelei's Slowbro. They should be deleted and I didn't blank them.--Kyurem147 (talk) 03:20, February 15, 2014 (UTC)
## Hi, I'm Fangirl111
but you can call me Ember. I was reading some Creepypasta about Pokémon (Strangled Red/Steven/S!3v3n, Glitchy Red, Lost Silver) and I was wondering (cuz I don't know that much about Pokémon) is Steven (Strangled Red) actually a character from Pokémon? Is Glitchy Red a character too and is Lost Silver (Gold) or are they all made up? And if they are actual characters, what order of generation are they? (I think it's like, Steven, Red, Gold, Ash or something, am I wrong?)
Ember —Preceding unsigned comment added by Fangirl111 (talkcontribs)
Oh, so Steven, Red, and Gold aren't characters? K.
Fangirl111 (Ember) (talk) 18:45, February 15, 2014 (UTC)
## Mirage
Hey X what do you about these. Mirage Rayquaza and Mirage Arcanine. These pokemon didn't actually appear, they were just summoned on mirage mewtwos body. Personally I don't think they count and are useful. It's common sense right? It only if it appears in form.--Kyurem147 (talk) 20:12, February 15, 2014 (UTC)
Well ok fine, but can you please do this favor. Please let me recreate Mirage Rayquaza. Rayquaza's my favorite pokemon. I'd gain satisfaction. It's just one page. If you help me on this one, I'll help on your project (if show me where it is). We're both on the mirage deal, all I want this one little article is all.--Kyurem147 (talk) 23:32, February 15, 2014 (UTC)
What do you mean Start acting professional? Sandbox's aren't professional and it won't change the fact that article was made by someone else you know. Besides once you add a text to a sandbox and want to put another, you have to erase the first. Surely you knew that right?--Kyurem147 (talk) 23:46, February 15, 2014 (UTC)
And do you mean minor character, I'm talking about appearance. They appeared on mewtwos body, I don't think that counts as character, more like a body part of the main pokemon--Kyurem147 (talk) 23:54, February 15, 2014 (UTC)
I'll upload the pics, but let ne tell you this, once you add a text to a sandbox and want to put another, you have to erase the first. What's the point of using it if you add, have to erase, then readd. It doesn't make sense. Answer me that.--Kyurem147 (talk) 00:19, February 16, 2014 (UTC)
Thnaks, but still answer this. Once you add a text to a sandbox and want to put another, you have to erase the first. What's the point of using it if you add, have to erase, then readd. It doesn't make sense. and what about that mirage deal?--Kyurem147 (talk) 23:27, February 16, 2014 (UTC)
You lost me at this: The times it shouldn't make articles are when a character mentions it has a Pokémon (but does not appear).--Kyurem147 (talk) 23:35, February 16, 2014 (UTC)
O I get it now. Ok I'm through with that, but still answer this. Once you add a text to a sandbox and want to put another, you have to erase the first. What's the point of using it if you add, have to erase, then readd. It doesn't make sense. Riddle me that.--Kyurem147 (talk) 00:19, February 17, 2014 (UTC)
I'm a little stumped on this:plan out rewriting the entire article as how it can look before putting it in. You can view it as "recreating", just without deleting. Why don't you show me how it's done on you're point view. So I'm convinced or just I need to I mean.--Kyurem147 (talk) 00:34, February 17, 2014 (UTC)
## Sorry
I checked Bulbapedia and I don't see any similarities in the Japanese names.
Signed, Winxfan1. (I am the ultimate fan of Winx Club) 22:36, February 15, 2014 (UTC)
Yeah, must be an error on the other editor's part.
Signed, Winxfan1. (I am the ultimate fan of Winx Club) 23:16, February 15, 2014 (UTC)
It's not right, this time I'm positive. It was never nicknamed.--Kyurem147 (talk) 21:29, February 16, 2014 (UTC)
I'm telling you, I swear it was never named. check http://bulbapedia.bulbagarden.net/wiki/Cher and see what mean.--Kyurem147 (talk) 21:33, February 16, 2014 (UTC)
## Re: Episode Plots
I mainly have a bit of a backlog for Gen III and II episodes which I still hope to actually add to the wiki (they're saved on my computer somewhere... I just need to find where!). RainbowShifter 16:36, February 17, 2014 (UTC)
## Re: Blocking
When blocking the vandals do you click all the boxes underneath the time limit and reasons? If so then that should prevent logged in users and anyone else from editing from that IP. If you did and this still happens then there isn't really anything we can do about it as the person is changing their IPs. We just have to keep reverting and hope that they get bored sooner or later. RainbowShifter 07:54, February 18, 2014 (UTC)
## Layout
Have you tried out Monobookin the preferances section about the layout, the layout is so much better than the original.Ellis99 (talk) 20:40, February 18, 2014 (UTC)
Ellis probably can tell because the people who use the other layout can sometimes leave behind stray pieces of code when they edit. ƒelinoel ~ (Talk) 05:34, February 21, 2014 (UTC)
## Layout
The only disappointment is it overlaps a few things, e.g main page and massage me back on how good it is.
## Protect Articles
Could you protect articles relating to Omanyte and Kabuto until this ridiculous twitch joke blows over and loses its popularity? -The Forgotten Beast (talk) 02:26, February 20, 2014 (UTC)
## Hi
Hey Energy X. Guess what, I'm actually starting to get the hang of renaming files now. I'm getting the hang of it now. Marioandluigibros12345 (talk) 03:48, February 20, 2014 (UTC)
## The First Movie
Hi Energy X, I'm watching the anime again, but I'm rather confused about the first moive. I thought it was between Indigo League and Orange Islands, but looking at their priemere, It shows somewhere between episodes in Indigo League. If you knwow, can you please tell me when I should watch the movie?
Already, thanks Finn Tracy (talk) 12:28, February 20, 2014 (UTC)
This is also with other movies, so I suppose they just come in between the episodes. Then, shall I do the American dates or the Japanese ones. For instance, Spell of the Unknown comes on July 8, 2000 in Japan, which is (in the Japanese order) after JE039, but in the American version, the movie comes on April 6, 2001, which is JE032 (in the American order). Can you please tell me? Finn Tracy (talk) 12:36, February 20, 2014 (UTC)
Ok i got it will do it tommorrow as my exams are going i extremely sorry for my inactiveness and i'm grateful to you as alwaysPlasma X ~~ Talk ~~ My Contributions 17:52, February 20, 2014 (UTC)
Plasma X, can you please explain to me what your talking about? And Enegry X, I found a website with the movies between the episodes. It's based on which Pokemon Ash and his friends/enemy's already have, and it seems to be right. http://www.tv.com/shows/pokemon/episodes/ Finn Tracy (talk) 14:39, February 21, 2014 (UTC)
## Music
I don't like the fact that the user quoted creepy pasta stuff. So I'm not happy about that. I say we don't allow that. Creepy pasta is not something that we want to be related to or link to in any way.
Slay Talk "Shadows wonder why we scream."23:07,2/21/2014 4,527
## FOB
Is the Festival of Battles thing over?
If not, how much longer does it have?
Slay Talk "Shadows wonder why we scream."23:12,2/21/2014 4,527
Community content is available under CC-BY-SA unless otherwise noted.
| 2020-08-13T09:15:33 |
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|
https://elist.ornl.gov/pipermail/visit-users/2010-March/006374.html
|
# [visit-users] Python to Session File ?
Kathleen S. Bonnell bonnell2 at llnl.gov
Mon Mar 15 12:20:28 EDT 2010
Steve,
Yes, I have downloaded the files, and have looked into the problem.
Definitely a few bugs, and they will be fixed for 2.0
1) SaveSession from cli on Windows, will save with '.session'
extension, even though '.vses' is the expected extension on windows.
2) RestoreSession window in gui only allows searching for files with
'.vses' extension
3) RestoreSession via gui window always prepends the user's visit
directory (eg %My Documents%).
To work around the issue with 1.12, you will need to restore your
session from the cli.
If you want to still run the gui, then open Controls->Command
In one of the tabs type:
RestoreSession("C:\\path\\to\\your\\session\\file\
\sessionfile.vses.session", 0)
Then click 'Execute'.
A cli command window will open, and your session should be restored.
I apologize for the inconvenience this issue is causing, and thank
you for bringing it to our attention.
Please let us know if you discover further issues.
Kathleen
On Mon, 2010-03-15 at 09:57 -0600, Alignment Services Company wrote:
> March 15, 2010 09:50A.
> Hi Kathleen,
> Bests, ss.
> ps: May I remove the subject links from our server (ie, Have you
>
>
> At 09:30 AM 3/15/2010, you wrote:
> >hello Steve,
> >
> >Thank you for all the files in support of the bug report. I will take
> >a look at it as soon as possible. If there is a way to make it work
> >with 1.12 I will let you know, otherwise the issue will be addressed
> >for 2.0.
> >
> >Kathleen
> >
> >On Sun, 2010-03-14 at 11:06 -0600, Alignment Services Company wrote:
> > > March 14, 2010 11:00A.MT. (GMT-07)
> > > Hello VisIt help:
> > > The *.VTK files for the below issue are per:
> > > www.**GoMeasure.com/Working/TestReportExample_sms1_PSToVisIT_1-VTKs.zip
> > > (~2KB)
> > > ss.
> > >
> > >
> > > ----------------------------
> > >
> > > March 13, 2010 12:15P.MT. (GMT-07)
> > > Hello VisIt help:
> > > fwiw, the debug log files for the below issue are per:
> > > www.**GoMeasure.com/Working/VLog_03132010-1213.zip
> > > (~40KB)
> > > ss.
> > >
> > >
> > > ----------------------------
> > >
> > > March 13, 2010 10:45A.MT. (GMT-07)
> > > Hello VisIt help:
> > >
> > > Still having zero success with VisIt GUI [Restore Session]:
> > >
> > >
> > > detail:
> > >
> > > 0) Using VisIt 1.12.2 {successfully installed from exe with all
> > > defaults} on single Windows XPpro SP3+.
> > >
> > > 1) Python script successfully executed (VisIt graphic is correct and
> > > manipulates properly; no errors reported in cmd window) from CLI
> > > utilizing SaveSession(full path to file) as last command in python
> > > script;
> > > example: SaveSession("C:\AATemp\Dillon_Jobs\GYRO_Alignment-Display
> > > \TestReportExample-sms\TestReportExample_sms1_PSToVisIT_1.vses")
> > > Subject script is within zip per:
> > > www.**GoMeasure.com/Working/TestReportExample_sms1_PSToVisIT_1.zip
> > > (~21KB)
> > >
> > > 2) Session File "C:\AATemp\Dillon_Jobs\GYRO_Alignment-Display
> > > \TestReportExample-sms
> > > \TestReportExample_sms1_PSToVisIT_1.vses.session" exists.
> > > Subject .session file is within same zip per above:
> > > www.**GoMeasure.com/Working/TestReportExample_sms1_PSToVisIT_1.zip
> > >
> > > 3) Launch VisIt GUI on desktop; Manually navigate via: [File],
> > > [Restore Session], {explicitly select session file per above}.
> > >
> > > 4) Error Results @ VisIt GUI:
> > > "Information" window
> > > "Error!"
> > > "VisIt could not locate the session file: C:\Documents and Settings
> > > \ASC\My Documents\VisIt 1.12.2\C:/AATemp/Dillon_Jobs/GYRO_Alignment-
> > > Display/TestReportExample-
> > > sms/TestReportExample_sms1_PSToVisIT_1.vses.session. Check that you
> > > provided the correct session file name or try including the entire
> > > path to the session file."
> > >
> > > notes:
> > > _removing the full path, within above step 1) , does not solve issue.
> > > _navigating to "C:\Documents and Settings\ASC\My Documents\VisIt
> > > 1.12.2\*.*" does not reveal any new files and nothing apparently
> > > related to the just attempted session save. Specifically there is one
> > > empty sub folder { \My Images\ } and two files { guiconfig for
> > > ASC.ini, state1.12.2.txt }.
> > >
> > >
> > >
> > > Thank you in advance for assistance in solving this issue.
> > > ss.
> > >
> > >
> > >
> > > === previous: ===
> > >
> > > At 03:32 PM 3/12/2010, you wrote:
> > > > The only difference is the ".session" vs ".vses" file extension. I
> > > > chose .vses for the Windows session file extension since windows
> > > > extensions are typically no longer than 3-4 characters and I was
> > > > trying to create an association between .vses and VisIt so they'd
> > > > open in VisIt when double-clicked. This has generated some confusion
> > > > over time and made it a little more of a chore to interchange
> > > > session files between Windows and UNIX, which I guess is something I
> > > > thought would rarely happen. We should probably use the same file
> > > > extension all the time.
> > > >
> > > >
> > > >
> > > > > I just tried this on a Linux machine with 1.12, and it appears to
> > > > > work okay for me. Just saying SaveSession("foo.session") appears
> > > > > to save to my current working directory. You might try adding a
> > > > > full path when saving the session. (You could get this in python
> > > > > with os.getcwd() if needed.)
> > > > >
> > > > > Are you on Windows? That might explain the file extension
> > > > > difference. I think if you just put "*" in the session file open
> > > > > box, it will force it to find all files, and then you could find
> > > > > the *.session file to open. It *should* work, I think, but maybe
> > > > > someone with more knowledge of the Windows session files wiykd
> > > > > know more.
> > > > >
> > > > > --
> > > > > Jeremy Meredith
> > > > > Oak Ridge National Laboratory
> > > > >
> > > > >
> > > > > > -----Original Message-----
> > > > > > From: Alignment Services Company [ mailto:ASC at GoMeasure.com]
> > > > > > Sent: Friday, March 12, 2010 3:12 PM
> > > > > > To: VisIt software users community
> > > > > > Subject: Re: [visit-users] Python to Session File ?
> > > > > >
> > > > > > March 12, 2010 1:00P.MT. (GMT-07)
> > > > > > Hello Hank,
> > > > > > In regard to below, when we add SaveSession(...) to the python
> > > > > > script, then execute, result is a "*.session" file (not .vses)
> > > > > > and
> > > > > > it is not located within our expected 'working'
> > > > > > folder. Additionally, the *.session does not open within the
> > > > > > VisIt
> > > > > > GUI which is apparently expecting a *.vses file. I suspect
> > > > > > there are
> > > > > > some Settings that we need to set within the script prior to
> > > > > > calling
> > > > > > SaveSession. ?
> > > > > > I've performed about a 1hr search through the documentation and
> > > > > > VP
> > > > > > interface but to little solution.
> > > > > > Any guidance is appreciated.
> > > > > > thx,
> > > > > > ss.
> > > > > >
> > > > > >
> > > > > > === previous: ===
> > > > > >
> > > > > > Will Do....Thanks Hank! ss.
> > > > > >
> > > > > > At 10:51 AM 3/11/2010, you wrote:
> > > > > > >Hi Steve,
> > > > > > >
> > > > > > >Can you run the script and then call "SaveSession()" from the
> > > > > > command
> > > > > > line?
> > > > > > >
> > > > > > >Best,
> > > > > > >Hank
> > > > > > >
> > > > > > >On Thu, Mar 11, 2010 at 9:50 AM, Alignment Services Company
> > > > > > ><ASC at gomeasure.com> wrote:
> > > > > > > >
> > > > > > > > March 11, 2010 10:30A. (GMT-07)
> > > > > > > > Hello visit-users at email.ornl.gov:
> > > > > > > >
> > > > > > > > We desire to convert VisIt display (via python script) to a
> > > > > > VisIt
> > > > > > Session
> > > > > > > > file (*.vses).
> > > > > > > > This so as to allow a further editing option from within
> > > > > > our
> > > > > > software.
> > > > > > > >
> > > > > > > > Detail:
> > > > > > > > Initial VisIt display is produced via: "VisIt.exe -cli -s
> > > > > > xxxxx.pys"
> > > > > > > > Then, we would like to optionally allow more detailed
> > > > > > editing of
> > > > > > the
> > > > > > > > display.
> > > > > > > > The full editing available via the VisIt GUI provides the
> > > > > > desired
> > > > > > > > functionality.
> > > > > > > > Thus, How might we turn a python generated VisIt display
> > > > > > into a
> > > > > > > session file
> > > > > > > > which can then be re-launched from the VisIt GUI ?
> > > > > > > >
> > > > > > > > This is not a one-time need; Intention is to add this
> > > > > > functionality to our
> > > > > > > > source-code which presently launches Visit pys per above.
> > > > > > > >
> > > > > > > >
> > > > > > > > Thank you in advance for any guidance,
> > > > > > > > S. Stokes
> > > > > > > >
> > > > > > > > ==||==
> > > > > > > > ALIGNMENT SERVICES, LLC
> > > > > > > > P.O. Box 7470
> > > > > > > > Jackson, Wyoming 83002
> > > > > > > > USA
> > > > > > > > 307-733-7245
> > > > > > > > ASC at GoMeasure.com
> > > > > > > > www.***GoMeasure.com
> > > > > > > > Person On-Call: 562-546-3638 { 1-JOB-LINE-ME-Up }
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > > > --
> > > > > > > > List subscription information:
> > > > > > > > https://***email.ornl.gov/mailman/listinfo/visit-users
> > > > > > > > Searchable list archives:
> > > > > > https://***email.ornl.gov/pipermail/visit-
> > > > > > users
> > > > > > > > VisIt Users Wiki: http://***visitusers.org/
> > > > > > > > Frequently Asked Questions for VisIt:
> > > > > > http://***visit.llnl.gov/FAQ.html
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > >--
> > > > > > >List subscription information:
> > > > > > > https://***email.ornl.gov/mailman/listinfo/visit-users
> > > > > > >Searchable list archives:
> > > > > > https://***email.ornl.gov/pipermail/visit-users
> > > > > > >VisIt Users Wiki: http://***visitusers.org/
> > > > > > >Frequently Asked Questions for VisIt:
> > > > > > http://***visit.llnl.gov/FAQ.html
> > > > > >
> > > > > > --
> > > > > > List subscription information:
> > > > > > https://***email.ornl.gov/mailman/listinfo/visit-users
> > > > > > Searchable list archives:
> > > > > > https://***email.ornl.gov/pipermail/visit-users
> > > > > > VisIt Users Wiki: http://***visitusers.org/
> > > > > > Frequently Asked Questions for VisIt:
> > > > > > http://***visit.llnl.gov/FAQ.html
> > > > >
> > > > > --
> > > > > List subscription information:
> > > > > https://***email.ornl.gov/mailman/listinfo/visit-users
> > > > > Searchable list archives:
> > > > > https://***email.ornl.gov/pipermail/visit-users
> > > > > VisIt Users Wiki: http://***visitusers.org/
> > > > > Frequently Asked Questions for VisIt:
> > > > > http://***visit.llnl.gov/FAQ.html
> > > >
> > > >
> > > > --
> > > > ======================================================================
> > > > Brad Whitlock Lawrence Livermore National
> > > > Laboratory
> > > > whitlock2 at llnl.gov
> > > > (925)424-2614
> > > > ======================================================================
> > > > --
> > > > List subscription information:
> > > > https://**email.ornl.gov/mailman/listinfo/visit-users
> > > > Searchable list archives: https://**email.ornl.gov/pipermail/visit-
> > > > users
> > > > VisIt Users Wiki: http://**visitusers.org/
> > > > Frequently Asked Questions for VisIt:
> > > > http://**visit.llnl.gov/FAQ.html
> > >
> > > --
> > > List subscription information:
> > > https://**email.ornl.gov/mailman/listinfo/visit-users
> > > Searchable list archives: https://**email.ornl.gov/pipermail/visit-
> > > users
> > > VisIt Users Wiki: http://**visitusers.org/
> > > Frequently Asked Questions for VisIt: http://**visit.llnl.gov/FAQ.html
> > >
> > >
> > >
> > > --
> > > List subscription information:
> > > https://**email.ornl.gov/mailman/listinfo/visit-users
> > > Searchable list archives: https://**email.ornl.gov/pipermail/visit-
> > > users
> > > VisIt Users Wiki: http://**visitusers.org/
> > > Frequently Asked Questions for VisIt: http://**visit.llnl.gov/FAQ.html
> > > --
> > > List subscription information:
> > > https://**email.ornl.gov/mailman/listinfo/visit-users
> > > Searchable list archives: https://**email.ornl.gov/pipermail/visit-
> > > users
> > > VisIt Users Wiki: http://**visitusers.org/
> > > Frequently Asked Questions for VisIt: http://**visit.llnl.gov/FAQ.html
> > > --
> > > List subscription information:
> > https://**email.ornl.gov/mailman/listinfo/visit-users
> > > Searchable list archives: https://**email.ornl.gov/pipermail/visit-users
> > > VisIt Users Wiki: http://**visitusers.org/
> > > Frequently Asked Questions for VisIt: http://**visit.llnl.gov/FAQ.html
> > >
> >
> >--
> >List subscription information:
> >https://*email.ornl.gov/mailman/listinfo/visit-users
> >Searchable list archives: https://*email.ornl.gov/pipermail/visit-users
> >VisIt Users Wiki: http://*visitusers.org/
> >Frequently Asked Questions for VisIt: http://*visit.llnl.gov/FAQ.html
>
> --
> List subscription information: https://*email.ornl.gov/mailman/listinfo/visit-users
> Searchable list archives: https://*email.ornl.gov/pipermail/visit-users
> VisIt Users Wiki: http://*visitusers.org/
> Frequently Asked Questions for VisIt: http://*visit.llnl.gov/FAQ.html
>
>
| 2018-02-18T22:12:48 |
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|
https://mooseframework.inl.gov/syntax/Transfers/index.html
|
# Transfers System
When running simulations that contain MultiApps—simulations running other sub-simulations—it is often required to move data to and from the sub-applications. Transfer objects in MOOSE are designed for this purpose.
note
Prior to understanding Transfers it is important to grasp the idea of MultiApps first, so please refer to the MultiApps documentation for additional information.
## Example Transfer
Assuming that the concept of MultiApps is understood, Transfers are best understood via an example problem. First, consider a "master" simulation that is solving the transient diffusion equation. This master simulation also includes two "sub" applications that rely on the average value of the unknown from the master application.
### The "master" Simulation
Listing 1 is an input file snippet showing the MultiApps block that includes a TransientMultiApp, this sub-application will execute along with the master (at the end of each timestep) as time progresses.
Listing 1: The MultiApps block of the "master" application that contains two sub-application that solves along with the master as time progresses.
[MultiApps]
[./pp_sub]
type = TransientMultiApp
app_type = MooseTestApp
positions = '0.5 0.5 0 0.7 0.7 0'
execute_on = timestep_end
input_files = sub.i
[../]
[]
(test/tests/transfers/multiapp_postprocessor_to_scalar/master.i)
For this example, the sub-applications require that the average from the master in the form of a scalar AuxVariable, see the AuxVariables documentation for further information. Therefore the master will transfer the average value (computed via the ElementAverageValue Postprocessor) to a scalar AuxVariable on each sub-application. As shown in Listing 2, the MultiAppPostprocessorToAuxScalarTransfer is provided for this purpose.
Listing 2: The Transfers block of the "master" application that contains a Transfer of a Postprocessor to a scalar AuxVariable on sub-applications.
[Transfers]
[./pp_transfer]
type = MultiAppPostprocessorToAuxScalarTransfer
direction = to_multiapp
multi_app = pp_sub
from_postprocessor = average
to_aux_scalar = from_master_app
[../]
[]
(test/tests/transfers/multiapp_postprocessor_to_scalar/master.i)
### The "sub" Simulations
For this simple example the sub-application must contain an appropriate AuxVariable to receiving the Postprocessor value from the master application.
Listing 3: The AuxVariables block of the "sub" application that contains a scalar that the master application will update.
[AuxVariables]
[./from_master_app]
order = FIRST
family = SCALAR
[../]
[]
(test/tests/transfers/multiapp_postprocessor_to_scalar/sub.i)
The sub-applications do not have any "knowledge" of the master application, and simply perform calculations that utilize the scalar variable, regardless of how this scalar is computed. This approach allows the sub-application input file to run in union of independent from the master without modification, which is useful for development and testing.
## Available Transfer Objects
The following is a complete list of the available Transfer objects, each links to a page with further details.
| 2019-02-22T14:02:18 |
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|
https://dofuswiki.fandom.com/wiki/Perceptor
|
## FANDOM
19,064 Pages
Perceptors (originally named Perceptors then renamed to Collectors, then changed back) are a kind of "Guild monster". Commonly called Percs, they can be placed by members of a Guild to gather XP and Drops from fights occuring in the area.
## Placing a PerceptorEdit
Designated guild members may place a Perceptor on their current map. To do that, a Perceptor Summoning Potion can be used. The Perceptor will get drops and experience gained in the area as if it were a participant in all combats there, and will hold them until a guild member collects them or until they are killed by another adventurer (who would get all the dropped items, and if they're a member of a guild, all the guild XP gathered).
Perceptors used to steal drops from other players, but now Perceptors have their own separate roll for drops, and, as they roll last, any drops they receive are simply extra drops, and not stolen from other players.
Not all maps accept perceptors. Places such as Class Temples, and non-subscriber zones no longer accept the placement of perceptors.
### AppearanceEdit
Perceptors hold a banner with the guild's logo. Their spots take on the primary color of said guild, and their bracers and headband correspond to the secondary colors.
## CharacteristicsEdit
As a guild gains levels, their Perceptors become more powerful. A Perceptor has 3000+(Guild level)*20 Vitality and 25% Resistances to all elements (fixed). Perceptors gain 5 stat points for each level their Guild gains. These points can be spent to raise any of the following:
Characteristic Base Max Cost
Prospecting 100 500 1 per point
Wisdom 0 400 1 per point
Pods 1000 5000 20 per point
Number of Perceptors 1 50 1 per 10 points
Spells* Level 0 Level 5 1 per 5 points
*See Spells section below for a more in depth description.
Perceptor spells and characteristics can be reset using a Perceptor deleveling potion.
## SpellsEdit
Just like characters, Perceptors have spells. In contrast to Characters who gain spells at level 1 and can use them without spending spell points, Perceptors begin with all spells at level 0 (and must raise them to level 1 to make them usable). Their spells range from Shields to Healing. Perceptor spell use is erratic. In battles where many defenders are present, they often move away from enemies or end their turn without acting.
Icon Name Element Short description
Aqueous Shield Reduces Water damage.
Glowing Shield Reduces Fire damage.
Earth Shield Reduces Earth damage.
Wind Shield Reduces Air damage.
Flame
Fire
High Fire damage, linear.
Cyclone
Air
Low/Average Air damage, No line of sight.
Wave
Water
Low/Average Water damage, linear, 3 square linear AoE.
Rock
Earth
Average to High Earth Damage, 2 squares circular AoE.
Word of Healing Heals target.
Unbewitchment Unbewitches target.
Mass Compulsion Increases allies damage in an AoE.
Destabilization -Critical Hits to target.
Spell level Points Total points
1 5 5
2 5 10
3 5 15
4 5 20
5 5 25
## Collecting PerceptorsEdit
Guild members who have the right to remove items from a Perceptor may do so if they're on the same map. As of 1.23, any of these exchanges also removes the Perceptor from the map. Removing a Perceptor does not return the potion used to place it.
Once withdrawn (or defeated), a Perceptor cannot be placed on the same map by the same Guild for $(Guild level) * 10 minutes$, so for a level 24 Guild, it would be 240 minutes, or 4 hours.
## Perceptor FightsEdit
Perceptor fights are similar to other forms of PvP, with a few differences:
• The preparation phase is significantly longer than with other fights in order to allow for Guild members to join the Perceptor's side.
• Only one character per IP can join a Perceptor fight.
• If the Perceptor is killed, the battle ends immediately even if there are still defenders from the Guild left alive.
• If you lose against a Perceptor you lose 3000 energy in addition to normal energy loss.
• When you lose a fight, you must wait 60 minutes before you can attack the same Perceptor.
• You cannot attack a Perceptor in a dungeon room if you logged in at that room, although you can still join the fight if another person starts it.
• Perceptors can no longer be attacked by characters who are below level 50.
## Defending a PerceptorEdit
When a Guild's Perceptor is attacked, every player in the Guild and their Alliance (if they have one) will receive a notification. By opening the guild/alliance menu and going to the Perceptor menu, they can join the fight by clicking "Join". Members with "Be the main Perceptor defender" right, has a priority in joining the defending of a perceptor.
Battles against the Perceptors are now 5 defenders against 5 offenders maximum (Perceptors not included) in order to speed up these battles and make them easier to organize.
Only one character per IP can be used in defense of the Perceptor.
Winners of a Perceptor battle are returned to where they were before the battle, while losers are returned to their last save point. Defenders of a Perceptor do not lose energy nor do their pets lose health.
## EventsEdit
Since 2010 (2014 not included), during Kwismas, Perceptors change appearance from their normal centaur like appearance to that of a reindeer.
Community content is available under CC-BY-SA unless otherwise noted.
| 2019-10-16T11:40:12 |
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|
https://www.itl.nist.gov/div898/handbook/mpc/section1/mpc123.htm
|
2. Measurement Process Characterization
2.1. Characterization
2.1.2. What is a check standard?
## Analysis
Short-term or level-1 standard deviations from J repetitions An analysis of the check standard data is the basis for quantifying random errors in the measurement process -- particularly time-dependent errors.
Given that we have a database of check standard measurements as described in data collection where
$$Y_{kj}(k=1, \,\ldots, \, K, \,\, j=1, \,\ldots, \, J)$$ represents the jth repetition on the kth day, the mean for the kth day is
$$\overline{Y}_{k \, \small{\bullet}} = \frac{1}{J}\sum_{j=1}^{J} Y_{kj}$$ and the short-term (level-1) standard deviation with v = J - 1 degrees of freedom is
$${\large s}_k = \sqrt{\frac{1}{J-1} \sum_{j=1}^{J} ( Y_{kj} - \overline{Y}_{k \, \small{\bullet}} ) ^2} \,\,\,\, .$$
Drawback of short-term standard deviations An individual short-term standard deviation will not be a reliable estimate of precision if the degrees of freedom is less than ten, but the individual estimates can be pooled over the K days to obtain a more reliable estimate. The pooled level-1 standard deviation estimate with v = K(J - 1) degrees of freedom is $${\large s}_1 = \sqrt{\frac{1}{K} \sum_{k=1}^{K} {\large s}_k^2} \,\,\,\, .$$ This standard deviation can be interpreted as quantifying the basic precision of the instrumentation used in the measurement process.
Process (level-2) standard deviation The level-2 standard deviation of the check standard is appropriate for representing the process variability. It is computed with v = K - 1 degrees of freedom as:
$${\large s}_{chkstd} = {\large s}_2 = \sqrt{\frac{1}{K-1} \sum_{k=1}^{K} \left( \overline{Y}_{k \, \small{\bullet}} - \overline{Y}_{\small{\bullet} \small{\bullet}} \right) ^2}$$ where $$\overline{Y}_{\small{\bullet} \small{\bullet}} = \frac{1}{K} \sum_{k=1}^{K} \overline{Y}_{k \, \small{\bullet}}$$ is the grand mean of the KJ check standard measurements.
Use in quality control The check standard data and standard deviations that are described in this section are used for controlling two aspects of a measurement process:
Case study: Resistivity check standard For an example, see the case study for resistivity where several check standards were measured J = 6 times per day over several days.
| 2021-08-03T23:06:01 |
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|
https://lammps.sandia.gov/doc/fix_wall_reflect.html
|
# fix wall/reflect/kk command
## Syntax
fix ID group-ID wall/reflect face arg ... keyword value ...
• ID, group-ID are documented in fix command
• wall/reflect = style name of this fix command
• one or more face/arg pairs may be appended
• face = xlo or xhi or ylo or yhi or zlo or zhi
arg = EDGE or constant or variable
EDGE = current lo edge of simulation box
constant = number like 0.0 or 30.0 (distance units)
variable = equal-style variable like v_x or v_wiggle
• zero or more keyword/value pairs may be appended
• keyword = units
units value = lattice or box
lattice = the wall position is defined in lattice units
box = the wall position is defined in simulation box units
## Examples
fix xwalls all wall/reflect xlo EDGE xhi EDGE
fix walls all wall/reflect xlo 0.0 ylo 10.0 units box
fix top all wall/reflect zhi v_pressdown
## Description
Bound the simulation with one or more walls which reflect particles in the specified group when they attempt to move through them.
Reflection means that if an atom moves outside the wall on a timestep by a distance delta (e.g. due to fix nve), then it is put back inside the face by the same delta, and the sign of the corresponding component of its velocity is flipped.
When used in conjunction with fix nve and run_style verlet, the resultant time-integration algorithm is equivalent to the primitive splitting algorithm (PSA) described by Bond. Because each reflection event divides the corresponding timestep asymmetrically, energy conservation is only satisfied to O(dt), rather than to O(dt^2) as it would be for velocity-Verlet integration without reflective walls.
Up to 6 walls or faces can be specified in a single command: xlo, xhi, ylo, yhi, zlo, zhi. A lo face reflects particles that move to a coordinate less than the wall position, back in the hi direction. A hi face reflects particles that move to a coordinate higher than the wall position, back in the lo direction.
The position of each wall can be specified in one of 3 ways: as the EDGE of the simulation box, as a constant value, or as a variable. If EDGE is used, then the corresponding boundary of the current simulation box is used. If a numeric constant is specified then the wall is placed at that position in the appropriate dimension (x, y, or z). In both the EDGE and constant cases, the wall will never move. If the wall position is a variable, it should be specified as v_name, where name is an equal-style variable name. In this case the variable is evaluated each timestep and the result becomes the current position of the reflecting wall. Equal-style variables can specify formulas with various mathematical functions, and include thermo_style command keywords for the simulation box parameters and timestep and elapsed time. Thus it is easy to specify a time-dependent wall position.
The units keyword determines the meaning of the distance units used to define a wall position, but only when a numeric constant or variable is used. It is not relevant when EDGE is used to specify a face position. In the variable case, the variable is assumed to produce a value compatible with the units setting you specify.
A box value selects standard distance units as defined by the units command, e.g. Angstroms for units = real or metal. A lattice value means the distance units are in lattice spacings. The lattice command must have been previously used to define the lattice spacings.
Here are examples of variable definitions that move the wall position in a time-dependent fashion using equal-style variables.
variable ramp equal ramp(0,10)
fix 1 all wall/reflect xlo v_ramp
variable linear equal vdisplace(0,20)
fix 1 all wall/reflect xlo v_linear
variable wiggle equal swiggle(0.0,5.0,3.0)
fix 1 all wall/reflect xlo v_wiggle
variable wiggle equal cwiggle(0.0,5.0,3.0)
fix 1 all wall/reflect xlo v_wiggle
The ramp(lo,hi) function adjusts the wall position linearly from lo to hi over the course of a run. The vdisplace(c0,velocity) function does something similar using the equation position = c0 + velocity*delta, where delta is the elapsed time.
The swiggle(c0,A,period) function causes the wall position to oscillate sinusoidally according to this equation, where omega = 2 PI / period:
position = c0 + A sin(omega*delta)
The cwiggle(c0,A,period) function causes the wall position to oscillate sinusoidally according to this equation, which will have an initial wall velocity of 0.0, and thus may impose a gentler perturbation on the particles:
position = c0 + A (1 - cos(omega*delta))
Styles with a gpu, intel, kk, omp, or opt suffix are functionally the same as the corresponding style without the suffix. They have been optimized to run faster, depending on your available hardware, as discussed on the Speed packages doc page. The accelerated styles take the same arguments and should produce the same results, except for round-off and precision issues.
These accelerated styles are part of the GPU, USER-INTEL, KOKKOS, USER-OMP and OPT packages, respectively. They are only enabled if LAMMPS was built with those packages. See the Build package doc page for more info.
You can specify the accelerated styles explicitly in your input script by including their suffix, or you can use the -suffix command-line switch when you invoke LAMMPS, or you can use the suffix command in your input script.
See the Speed packages doc page for more instructions on how to use the accelerated styles effectively.
Restart, fix_modify, output, run start/stop, minimize info:
No information about this fix is written to binary restart files. None of the fix_modify options are relevant to this fix. No global or per-atom quantities are stored by this fix for access by various output commands. No parameter of this fix can be used with the start/stop keywords of the run command. This fix is not invoked during energy minimization.
## Restrictions
Any dimension (xyz) that has a reflecting wall must be non-periodic.
A reflecting wall should not be used with rigid bodies such as those defined by a “fix rigid” command. This is because the wall/reflect displaces atoms directly rather than exerts a force on them. For rigid bodies, use a soft wall instead, such as fix wall/lj93. LAMMPS will flag the use of a rigid fix with fix wall/reflect with a warning, but will not generate an error.
| 2020-08-10T12:12:51 |
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|
https://firas.moosvi.com/oer/physics_bank/content/public/021.Circuits/Ohm%27s%20Law/OSUPv2p10_23/OSUPv2p10_23.html
|
Unknown Voltage Source#
Part 1#
What is the internal resistance of a voltage source if its terminal potential drops by $${{ params.dV }}\rm\ V$$ when the current supplied increases by $${{ params.dI }}\rm\ A$$?
Answer Section#
Please enter a numeric value.
Part 2#
Can the emf of the voltage source be found with the information supplied?
pl-answer-panel#
$$R=$$ $$\rm\ \Omega$$
Attribution#
Problem is from the OpenStax University Physics Volume 2 textbook, licensed under the CC-BY 4.0 license.
| 2022-09-26T02:51:14 |
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|
https://www.detailedpedia.com/wiki-Christopher_Latham_Sholes
|
# Christopher Latham Sholes
C. Latham Sholes
Christopher Latham Sholes
Member of the Wisconsin Senate
from the 8th district
In office
January 9, 1856 – January 13, 1858
Succeeded bySamuel R. McClellan
Member of the Wisconsin Senate
from the 16th district
In office
June 5, 1848 – January 9, 1850
Preceded byPosition Established
Succeeded byElijah Steele
Member of the Wisconsin State Assembly
from the Kenosha 2nd district
In office
January 12, 1853 – January 11, 1854
Preceded byLathrop Burgess
Succeeded byJesse Hooker
Member of the Wisconsin State Assembly
from the Kenosha 1st district
In office
January 14, 1852 – January 12, 1853
Preceded byObed Hale
Succeeded byJames C. McKisson
Personal details
Born
Christopher Latham Sholes
February 14, 1819
Mooresburg, Penn., U.S.
DiedFebruary 17, 1890 (aged 71)
Milwaukee, Wisconsin, U.S.
Resting placeForest Home Cemetery, [1]
NationalityAmerican
Political party
Spouse(s)Mary Jane McKinney (died 1888)
Children
• Charles Latham Sholes
• (1843–1902)
• Clarence Gordon Sholes
• (1845–1926)
• Mary Katherine (Tyrrell)
• (1847–1896)
• Frederick Sholes
• (1847–1933)
• Louis C. Sholes
• (1849–1914)
• Elizabeth (Gilmore)
• (1852–1937)
• Lillian (Fortier)
• (1856–1941)
• George Orrin Sholes
• (1859–1894)
• Jessie Sholes
• (1861–1898)
• Zalmon Gilbert Sholes
• (1864–1917)
MotherCatherine (Cook) Sholes
FatherOrrin Sholes
RelativesCharles Sholes (brother)
OccupationPrinter, inventor, legislator
Known for"The Father of the typewriter,"[1] inventor of the QWERTY keyboard
Signature
Christopher Latham Sholes (February 14, 1819 – February 17, 1890) was an American inventor who invented the QWERTY keyboard,[2] and, along with Samuel W. Soule, Carlos Glidden and John Pratt, has been contended to be one of the inventors of the first typewriter in the United States.[3][4][5] He was also a newspaper publisher and Wisconsin politician. In his time, Sholes went by the names C. Latham Sholes, Latham Sholes, or C. L. Sholes, but never "Christopher Sholes" or "Christopher L. Sholes".
## Youth and political career
Born in Mooresburg, in Montour County, Pennsylvania, Sholes moved to nearby Danville and worked there as an apprentice to a printer. After completing his apprenticeship, Sholes moved to Milwaukee, Wisconsin, in 1837, and later to Southport, Wisconsin (present-day Kenosha). He became a newspaper publisher and politician, serving in the Wisconsin State Senate from 1848 to 1849 as a Democrat, in the Wisconsin State Assembly from 1852 to 1853 as a Free Soiler, and again in the Senate as a Republican from 1856 to 1857.[6][7] He was instrumental in the successful movement to abolish capital punishment in Wisconsin; his newspaper, The Kenosha Telegraph, reported on the trial of John McCaffary in 1851, and then in 1853 he led the campaign in the Wisconsin State Assembly.[8] He was the younger brother of Charles Sholes (1816–1867), who was also a newspaper publisher and politician who served in both houses of the Wisconsin State Legislature and as mayor of Kenosha.[9]
## The "Voree Record"
In 1845, Sholes was working as editor of the Southport Telegraph, a small newspaper in Kenosha. During this time, he heard about the alleged discovery of the Voree Record, a set of three minuscule brass plates unearthed by James J. Strang, a would-be successor to Joseph Smith, founder of the Latter Day Saint movement.[10] Strang asserted that this proved that he was a true prophet of God, and he invited the public to call upon him and see the plates for themselves. Sholes accordingly visited Strang, examined his "Voree Record," and wrote an article about their meeting. He indicated that while he could not accept Strang's plates or his prophetic claims, Strang himself seemed to be "honest and earnest" and his disciples were "among the most honest and intelligent men in the neighborhood." As for the "record" itself, Sholes indicated that he was "content to have no opinion about it."[11]
## Inventing the typewriter
John Pratt's Pterotype, the inspiration for Sholes in July 1867, a version close to the stock model advocated by fellow inventor Frank Haven Hall.
Wisconsin Historical Marker
Typewriters with various keyboards had been invented as early as 1714 by Henry Mill and have been reinvented in various forms throughout the 1800s. It is believed that Sholes drew inspiration from the inventions of others, including those of Frank Haven Hall, Samuel W. Soule, Carlos Glidden, Giuseppe Ravizza and, in particular, John Pratt, whose mention in an 1867 Scientific American article Glidden is known to have shown Sholes. Sholes' typewriter improved on both the symplicity and efficiency of previous models, which led to his successful patent and commercial success.[12]
Sholes had moved to Milwaukee and became the editor of a newspaper. Following a strike by compositors at his printing press, he tried building a machine for typesetting, but this was a failure and he quickly abandoned the idea. He arrived at the typewriter through a different route. His initial goal was to create a machine to number pages of a book, tickets and so on. He began work on this at a machine shop in Milwaukee, together with a fellow printer Samuel W. Soule They patented a numbering machine on November 13, 1866.[12]
Sholes and Soule showed their machine to Carlos Glidden, a lawyer and amateur inventor at the machine shop who was working on a mechanical plow. Glidden wondered if the machine could not be made to produce letters and words as well. Further inspiration came in July 1867, when Sholes came across a short note in Scientific American[13] describing the "Pterotype", a prototype typewriter that had been invented by John Pratt. From the description, Sholes decided that the Pterotype was too complex and set out to make his own machine, whose name he got from the article: the typewriting machine, or typewriter.
For this project, Soule was again enlisted and Glidden joined them as a third partner to provide funding. The Scientific American article (unillustrated) had figuratively used the phrase "literary piano"; the first model that the trio built had a keyboard literally resembling a piano. It had black keys and white keys, laid out in two rows. It did not contain keys for the numerals 0 or 1 because the letters O and I were deemed sufficient:
3 5 7 9 N O P Q R S T U V W X Y Z
2 4 6 8 . A B C D E F G H I J K L M
The first row was made of ivory and the second of ebony, the rest of the framework was wooden. Despite the evident prior art by Pratt, it was in this same form that Sholes, Glidden and Soule were granted patents for their invention on June 23, 1868[14] and July 14.[15] The first document to be produced on a typewriter was a contract that Sholes had written, in his capacity as the comptroller for the city of Milwaukee. Machines similar to Sholes's had been previously used by the blind for embossing, but by Sholes's time the inked ribbon had been invented, which made typewriting in its current form possible.[12]
At this stage, the Sholes-Glidden-Soule typewriter was only one among dozens of similar inventions. They wrote hundreds of letters on their machine to various people, one of whom was James Densmore of Meadville, Pennsylvania. Densmore believed that the typewriter would be highly profitable, and offered to buy a share of the patent, without even having seen the machine. The trio immediately sold him one-fourth of the patent in return for his paying all their expenses so far. When Densmore eventually examined the machine in March 1867, he declared that it was good for nothing in its current form, and urged them to start improving it. Discouraged, Soule and Glidden left the project, leaving Sholes and Densmore in sole possession of the patent.
Realizing that stenographers would be among the first and most important users of the machine, and therefore best in a position to judge its suitability, they sent experimental versions to a few stenographers. The most important of them was James O. Clephane of Washington D.C., who tried the instruments as no one else had tried them, subjecting them to such unsparing tests that he destroyed them, one after another, as fast as they could be made and sent to him. His judgments were similarly caustic, causing Sholes to lose his patience and temper. But Densmore insisted that this was exactly what they needed:[12][16]
This candid fault-finding is just what we need. We had better have it now than after we begin manufacturing. Where Clephane points out a weak lever or rod let us make it strong. Where a spacer or an inker works stiffly, let us make it work smoothly. Then, depend upon Clephane for all the praise we deserve.
Sholes typewriter, 1873. Buffalo History Museum.
Sholes took this advice and set to improve the machine at every iteration, until they were satisfied that Clephane had taught them everything he could. By this time, they had manufactured 50 machines or so, at an average cost of $250 (equivalent to almost$5,000 in 2020). They decided to have the machine examined by an expert mechanic, who directed them to E. Remington and Sons (which later became the Remington Arms Company), manufacturers of firearms, sewing machines and farm tools. In early 1873, they approached Remington, who decided to buy the patent from them. Sholes sold his half for $12,000, while Densmore, still a stronger believer in the machine, insisted on a royalty, which would eventually fetch him$1.5 million.[12]
Sholes returned to Milwaukee and continued to work on new improvements for the typewriter throughout the 1870s, which included the QWERTY keyboard (1873).[17] James Densmore had suggested splitting up commonly used letter combinations in order to solve a jamming problem caused by the slow method of recovering from a keystroke: weights, not springs, returned all parts to the "rest" position. This concept was later refined by Sholes and the resulting QWERTY layout is still used today on both typewriters and English language computer keyboards, although the jamming problem no longer exists.
Sholes died on February 17, 1890, after battling tuberculosis for nine years.[18] He is buried at Forest Home Cemetery in Milwaukee.
## Notes
1. ^ a b Weller, Charles Edward (1918). The Early History of the Typewriter. Chase & Shepard, printers. p. 75.
2. ^ "Early Typewriter History"
3. ^ Larson, Erik (February 10, 2004). A Devil in the White City: Murder, Magic, and Madness at the Fair that Changed America. New York: Vintage Books, a Division of Random House, Inc. p. 291 (Adobe epub book). ISBN 9781400076314.
4. ^ Hendrickson, Walter B. (1956). "The Three Lives of Frank H. Hall" (PDF). Journal of the Illinois State Historical Society. University of Illinois Press. 49 (3). Archived from the original (PDF) on August 6, 2010.
5. ^ Anonymous (April 24, 2011). "Hall Braille Writer". American Printing House for the Blind, Inc. Archived from the original on April 27, 2012. Retrieved February 29, 2012.
6. ^ "Sholes, Christopher Pichon 1819 - 1890". Wisconsinhistory.org. Retrieved October 12, 2011.
7. ^ "Archived copy" (PDF). Archived from the original (PDF) on December 9, 2006. Retrieved January 17, 2015.CS1 maint: archived copy as title (link)
8. ^ "A Brief History of Wisconsin's Death Penalty". Wisbar.org. Archived from the original on August 14, 2012. Retrieved October 12, 2011.
9. ^ "Sholes, Charles Clark 1816 - 1867". Wisconsinhistory.org. Retrieved October 12, 2011.
10. ^ See "Voree Plates" at http://www.strangite.org/Plates.htm Archived 2012-09-17 at archive.today.
11. ^ Fitzpatrick, Doyle, The King Strang Story (National Heritage, 1970), pp. 36-37.
12. Iles, George (1912). Leading American Inventors. New York: Henry Holt and Company.
13. ^ "Type-Writing Machine". Scientific American. 17 (1): 3. July 6, 1867. Retrieved January 14, 2009.
14. ^ "#79265". Retrieved October 12, 2011.
15. ^ "#79868". Retrieved October 12, 2011.
16. ^ Mares, G.C. (1909), The history of the typewriter, successor to the pen: An illustrated account of the origin, rise, and development of the writing machine, London: Guilbert Putnam Reprinted by Post-era Books, Arcadia, CA, 1985.
17. ^ "The Sholes (QWERTY) Keyboard". Cs.ttu.ee. Archived from the original on October 9, 2011. Retrieved October 12, 2011.
18. ^ "Death of an Inventor". Scranton Tribune. Milwaukee, Wisconsin. February 19, 1890. p. 2. Retrieved January 6, 2021 – via Newspapers.com.
## References
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https://phys.libretexts.org/Bookshelves/College_Physics/Book%3A_College_Physics_(OpenStax)/33%3A_Particle_Physics
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$$\require{cancel}$$
# 33: Particle Physics
Particle physics (or high energy physics) studies the nature of the particles that constitute matter (particles with mass) and radiation (massless particles). Although the word "particle" can refer to various types of very small objects (e.g., protons, gas particles, or even household dust), "particle physics" usually investigates the irreducibly smallest detectable particles and the irreducibly fundamental force fields necessary to explain them.
• 33.1: Prelude to Particle Physics
In its study, we have found a relatively small number of atoms with systematic properties that explained a tremendous range of phenomena. Nuclear physics is concerned with the nuclei of atoms and their substructures. Here, a smaller number of components—the proton and neutron—make up all nuclei. Exploring the systematic behavior of their interactions has revealed even more about matter, forces, and energy.
• 33.2: The Yukawa Particle and the Heisenberg Uncertainty Principle Revisited
Particle physics as we know it today began with the ideas of Hideki Yukawa in 1935. Yukawa was interested in the strong nuclear force in particular and found an ingenious way to explain its short range. His idea is a blend of particles, forces, relativity, and quantum mechanics that is applicable to all forces. Yukawa proposed that force is transmitted by the exchange of particles (called carrier particles). The field consists of these carrier particles.
• 33.3: The Four Basic Forces
There are only four distinct basic forces in all of nature. This is a remarkably small number considering the myriad phenomena they explain. Particle physics is intimately tied to these four forces. Certain fundamental particles, called carrier particles, carry these forces, and all particles can be classified according to which of the four forces they feel.
• 33.4: Accelerators Create Matter from Energy
The fundamental process in creating previously unknown particles is to accelerate known particles, such as protons or electrons, and direct a beam of them toward a target. I the energy of the incoming particles is large enough, new matter is sometimes created in the collision. Limitations are placed on what can occur by known conservation laws, such as conservation of mass-energy, momentum, and charge. Even more interesting are the unknown limitations provided by nature.
• 33.5: Particles, Patterns, and Conservation Laws
After World War II, accelerators energetic enough to create these particles were built. Not only were predicted and known particles created, but many unexpected particles were observed. Initially called elementary particles, their numbers proliferated to dozens and then hundreds, and the term “particle zoo” became the physicist’s lament at the lack of simplicity. But patterns were observed in the particle zoo that led to simplifying ideas such as quarks, as we shall soon see.
• 33.6: Quarks - Is That All There Is?
Quarks have been mentioned at various points in this text as fundamental building blocks and members of the exclusive club of truly elementary particles. Note that an elementary or fundamental particle has no substructure (it is not made of other particles) and has no finite size other than its wavelength. This does not mean that fundamental particles are stable—some decay, while others do not. Keep in mind that all leptons seem to be fundamental, whereas no hadrons are fundamental.
• 33.7: GUTs - The Unification of Forces
The search for a correct theory linking the four fundamental forces, called the Grand Unified Theory (GUT), is explored in this section in the realm of particle physics. Frontiers of Physics expands the story in making a connection with cosmology, on the opposite end of the distance scale.
• 33.E: Special Relativity (Exercise)
Thumbnail: In this Feynman diagram, an electron and apositron annihilate, producing a photon(represented by the blue sine wave) that becomes aquark–antiquark pair, after which the antiquark radiates a gluon (represented by the green helix). Image used with permission (CC-SA-BY 2.5; Joel Holdsworth).
# Contributors
• Paul Peter Urone (Professor Emeritus at California State University, Sacramento) and Roger Hinrichs (State University of New York, College at Oswego) with Contributing Authors: Kim Dirks (University of Auckland) and Manjula Sharma (University of Sydney). This work is licensed by OpenStax University Physics under a Creative Commons Attribution License (by 4.0).
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https://www.zbmath.org/authors/?q=ai%3Adel-piero.gianpietro
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# zbMATH — the first resource for mathematics
## Del Piero, Gianpietro
Compute Distance To:
Author ID: del-piero.gianpietro Published as: Del Piero, G.; Del Piero, Gianpietro; del Piero, G.; del Piero, Gianpietro External Links: MGP · Wikidata
Documents Indexed: 55 Publications since 1972, including 5 Books Biographic References: 4 Publications
all top 5
#### Co-Authors
36 single-authored 3 Deseri, Luca 3 Maceri, Franco 3 Owen, David R. 2 Rizzoni, Raffaella 2 Ru, Chongqing 2 Truskinovsky, Lev 1 Choksi, Rustum 1 Fonseca, Irene 1 Huo, Yongzong 1 Lancioni, Giovanni 1 March, Riccardo 1 Pampolini, Giampiero 1 Sampaio, Rubens
all top 5
#### Serials
12 Journal of Elasticity 4 Archive for Rational Mechanics and Analysis 4 Continuum Mechanics and Thermodynamics 3 Meccanica 3 Mathematics and Mechanics of Solids 3 Mathematics and Mechanics of Complex Systems 2 CISM International Centre for Mechanical Sciences. Courses and Lectures 1 Applicable Analysis 1 Archives of Mechanics 1 International Journal of Plasticity 1 International Journal of Solids and Structures 1 Journal of the Mechanics and Physics of Solids 1 Quarterly of Applied Mathematics 1 Note di Matematica 1 Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Serie IX. Rendiconti Lincei. Matematica e Applicazioni 1 Matemática Aplicada e Computacional 1 ISNM. International Series of Numerical Mathematics 1 Bulletin of the Transilvania University of Braşov. Series III. Mathematics, Informatics, Physics
all top 5
#### Fields
53 Mechanics of deformable solids (74-XX) 8 Calculus of variations and optimal control; optimization (49-XX) 6 General and overarching topics; collections (00-XX) 2 History and biography (01-XX) 2 Operations research, mathematical programming (90-XX) 1 Linear and multilinear algebra; matrix theory (15-XX) 1 Partial differential equations (35-XX) 1 Operator theory (47-XX) 1 Numerical analysis (65-XX) 1 Mechanics of particles and systems (70-XX) 1 Classical thermodynamics, heat transfer (80-XX)
#### Citations contained in zbMATH
36 Publications have been cited 380 times in 260 Documents Cited by Year
Structured deformations of continua. Zbl 0795.73005
Del Piero, Gianpietro; Owen, David R.
1993
Constitutive equation and compatibility of the external loads for linear elastic masonry-like materials. Zbl 0679.73002
Del Piero, Gianpietro
1989
On the concepts of state and free energy in linear viscoelasticity. Zbl 0891.73024
Del Piero, Gianpietro; Deseri, Luca
1997
Some properties of the set of fourth-order tensors, with application to elasticity. Zbl 0412.73007
Del Piero, Gianpietro
1979
A variational model for fracture mechanics: Numerical experiments. Zbl 1166.74413
Del Piero, Gianpietro; Lancioni, Giovanni; March, Riccardo
2007
On the analytic expression of the free energy in linear viscoelasticity. Zbl 0891.73025
Del Piero, Gianpietro; Deseri, Luca
1996
Limit analysis and no-tension materials. Zbl 0911.73022
Del Piero, G.
1998
On the completeness of crystallographic symmetries in the description of the symmetries of the elastic tensor. Zbl 0755.73015
Huo, Yongzong; Del Piero, Gianpietro
1991
Macro- and micro-cracking in one-dimensional elasticity. Zbl 1004.74064
Del Piero, Gianpietro; Truskinovsky, Lev
2001
Structured deformations as energy minimizers in models of fracture and hystersis. Zbl 1001.74566
Choksi, R.; del Piero, G.; Fonseca, I.; Owen, D.
1999
Integral-gradient formulae for structured deformations. Zbl 0836.73023
Del Piero, Gianpietro; Owen, David R.
1995
A variational approach to fracture and other inelastic phenomena. Zbl 1394.74163
Del Piero, Gianpietro
2013
Elastic bars with cohesive energy. Zbl 1170.74378
Del Piero, Gianpietro; Truskinovsky, Lev
2009
Weak local minimizers in finite elasticity. Zbl 1159.74356
Del Piero, Gianpietro; Rizzoni, Raffaella
2008
The energy of a one-dimensional structured deformation. Zbl 1028.74019
Del Piero, Gianpietro
2001
Lower bounds for the critical loads of elastic bodies. Zbl 0437.73032
Del Piero, Gianpietro
1980
On the elastic-plastic material element. Zbl 0354.73007
Del Piero, Gianpietro
1975
Nonclassical continua, pseudobalance, and the law of action and reaction. Zbl 1400.74007
Del Piero, Gianpietro
2014
Monotonic, completely monotonic, and exponential relaxation functions in linear viscoelasticity. Zbl 0855.73026
Del Piero, Gianpietro; Deseri, Luca
1995
The variational structure of classical plasticity. Zbl 1401.74052
Del Piero, Gianpietro
2018
An axiomatic framework for the mechanics of generalized continua. Zbl 1391.74007
Del Piero, Gianpietro
2018
On the decomposition of the deformation gradient in plasticity. Zbl 1387.74028
Del Piero, Gianpietro
2018
The relaxed work functional in linear viscoelasticity. Zbl 1181.74020
Del Piero, Gianpietro
2004
Interface energies and structured deformations in plasticity. Zbl 1045.74017
Del Piero, Gianpietro
2002
Recent developments in the mechanics of materials which do not support tension. Zbl 0722.73016
Del Piero, G.
1990
“Reality” and representation in mechanics: the legacy of Walter Noll. Zbl 1415.74001
Del Piero, Gianpietro
2019
Strain localization in polyurethane foams: experiments and theoretical model. Zbl 1189.74010
Pampolini, Giampiero; Del Piero, Gianpietro
2009
Two-sided estimates for local minimizers in compressible elasticity. Zbl 1423.74124
Del Piero, G.; Rizzoni, R.
2008
Bi-modal cohesive energies. Zbl 1097.74009
Del Piero, Gianpietro
2006
A class of fit regions and a universe of shapes for continuum mechanics. Zbl 1074.74008
Del Piero, Gianpietro
2003
Representation theorems for hemitropic and transversely isotropic tensor functions. Zbl 0922.73002
Del Piero, Gianpietro
1998
Unilateral problems in structural analysis IV. Proceedings of the fourth meeting, Capri, Italy, June 14-16, 1989. Zbl 0745.00040
Del Piero, Gianpietro (ed.); Maceri, Franco (ed.)
1991
Well-posedness and Galerkin approximation for unbounded operators in Banach spaces. Zbl 0592.65034
Del Piero, G.
1985
Unilateral problems in structural analysis. Proceedings of the Second Meeting on Unilateral Problems in Structural Analysis, Ravello (Italy), September 22-24, 1983. Zbl 0581.00018
Del Piero, G. (ed.); Maceri, F. (ed.)
1985
On a mathematical theory of elastic-plastic materials. Zbl 0315.73056
Del Piero, Gianpietro
1975
A priori bounds for the plastic dissipation of elastic-plastic oscillators. Zbl 0256.73015
Del Piero, Gianpietro
1972
“Reality” and representation in mechanics: the legacy of Walter Noll. Zbl 1415.74001
Del Piero, Gianpietro
2019
The variational structure of classical plasticity. Zbl 1401.74052
Del Piero, Gianpietro
2018
An axiomatic framework for the mechanics of generalized continua. Zbl 1391.74007
Del Piero, Gianpietro
2018
On the decomposition of the deformation gradient in plasticity. Zbl 1387.74028
Del Piero, Gianpietro
2018
Nonclassical continua, pseudobalance, and the law of action and reaction. Zbl 1400.74007
Del Piero, Gianpietro
2014
A variational approach to fracture and other inelastic phenomena. Zbl 1394.74163
Del Piero, Gianpietro
2013
Elastic bars with cohesive energy. Zbl 1170.74378
Del Piero, Gianpietro; Truskinovsky, Lev
2009
Strain localization in polyurethane foams: experiments and theoretical model. Zbl 1189.74010
Pampolini, Giampiero; Del Piero, Gianpietro
2009
Weak local minimizers in finite elasticity. Zbl 1159.74356
Del Piero, Gianpietro; Rizzoni, Raffaella
2008
Two-sided estimates for local minimizers in compressible elasticity. Zbl 1423.74124
Del Piero, G.; Rizzoni, R.
2008
A variational model for fracture mechanics: Numerical experiments. Zbl 1166.74413
Del Piero, Gianpietro; Lancioni, Giovanni; March, Riccardo
2007
Bi-modal cohesive energies. Zbl 1097.74009
Del Piero, Gianpietro
2006
The relaxed work functional in linear viscoelasticity. Zbl 1181.74020
Del Piero, Gianpietro
2004
A class of fit regions and a universe of shapes for continuum mechanics. Zbl 1074.74008
Del Piero, Gianpietro
2003
Interface energies and structured deformations in plasticity. Zbl 1045.74017
Del Piero, Gianpietro
2002
Macro- and micro-cracking in one-dimensional elasticity. Zbl 1004.74064
Del Piero, Gianpietro; Truskinovsky, Lev
2001
The energy of a one-dimensional structured deformation. Zbl 1028.74019
Del Piero, Gianpietro
2001
Structured deformations as energy minimizers in models of fracture and hystersis. Zbl 1001.74566
Choksi, R.; del Piero, G.; Fonseca, I.; Owen, D.
1999
Limit analysis and no-tension materials. Zbl 0911.73022
Del Piero, G.
1998
Representation theorems for hemitropic and transversely isotropic tensor functions. Zbl 0922.73002
Del Piero, Gianpietro
1998
On the concepts of state and free energy in linear viscoelasticity. Zbl 0891.73024
Del Piero, Gianpietro; Deseri, Luca
1997
On the analytic expression of the free energy in linear viscoelasticity. Zbl 0891.73025
Del Piero, Gianpietro; Deseri, Luca
1996
Integral-gradient formulae for structured deformations. Zbl 0836.73023
Del Piero, Gianpietro; Owen, David R.
1995
Monotonic, completely monotonic, and exponential relaxation functions in linear viscoelasticity. Zbl 0855.73026
Del Piero, Gianpietro; Deseri, Luca
1995
Structured deformations of continua. Zbl 0795.73005
Del Piero, Gianpietro; Owen, David R.
1993
On the completeness of crystallographic symmetries in the description of the symmetries of the elastic tensor. Zbl 0755.73015
Huo, Yongzong; Del Piero, Gianpietro
1991
Unilateral problems in structural analysis IV. Proceedings of the fourth meeting, Capri, Italy, June 14-16, 1989. Zbl 0745.00040
Del Piero, Gianpietro (ed.); Maceri, Franco (ed.)
1991
Recent developments in the mechanics of materials which do not support tension. Zbl 0722.73016
Del Piero, G.
1990
Constitutive equation and compatibility of the external loads for linear elastic masonry-like materials. Zbl 0679.73002
Del Piero, Gianpietro
1989
Well-posedness and Galerkin approximation for unbounded operators in Banach spaces. Zbl 0592.65034
Del Piero, G.
1985
Unilateral problems in structural analysis. Proceedings of the Second Meeting on Unilateral Problems in Structural Analysis, Ravello (Italy), September 22-24, 1983. Zbl 0581.00018
Del Piero, G. (ed.); Maceri, F. (ed.)
1985
Lower bounds for the critical loads of elastic bodies. Zbl 0437.73032
Del Piero, Gianpietro
1980
Some properties of the set of fourth-order tensors, with application to elasticity. Zbl 0412.73007
Del Piero, Gianpietro
1979
On the elastic-plastic material element. Zbl 0354.73007
Del Piero, Gianpietro
1975
On a mathematical theory of elastic-plastic materials. Zbl 0315.73056
Del Piero, Gianpietro
1975
A priori bounds for the plastic dissipation of elastic-plastic oscillators. Zbl 0256.73015
Del Piero, Gianpietro
1972
all top 5
all top 5
#### Cited in 61 Serials
45 Journal of Elasticity 22 Meccanica 21 Continuum Mechanics and Thermodynamics 18 Computer Methods in Applied Mechanics and Engineering 17 Mathematics and Mechanics of Solids 15 Archive for Rational Mechanics and Analysis 15 European Journal of Mechanics. A. Solids 12 Journal of the Mechanics and Physics of Solids 8 Quarterly of Applied Mathematics 7 Acta Mechanica 7 International Journal of Engineering Science 5 International Journal for Numerical Methods in Engineering 4 International Journal of Solids and Structures 4 M$$^3$$AS. Mathematical Models & Methods in Applied Sciences 3 Journal of Mathematical Analysis and Applications 3 ZAMP. Zeitschrift für angewandte Mathematik und Physik 3 Discrete and Continuous Dynamical Systems. Series B 3 Mathematics and Mechanics of Complex Systems 2 Mechanics Research Communications 2 Annales de l’Institut Henri Poincaré. Analyse Non Linéaire 2 Mathematical and Computer Modelling 2 Journal of Nonlinear Science 2 Proceedings of the Royal Society of London. A. Mathematical, Physical and Engineering Sciences 1 Applicable Analysis 1 Archives of Mechanics 1 Journal of Mathematical Physics 1 Mathematical Methods in the Applied Sciences 1 Rheologica Acta 1 Wave Motion 1 Zeitschrift für Angewandte Mathematik und Mechanik (ZAMM) 1 Journal of Geometry and Physics 1 Annali di Matematica Pura ed Applicata. Serie Quarta 1 Applied Mathematics and Computation 1 Applied Mathematics and Optimization 1 Journal of Computational and Applied Mathematics 1 Journal of Optimization Theory and Applications 1 Mathematics and Computers in Simulation 1 Transactions of the American Mathematical Society 1 Applied Mathematics and Mechanics. (English Edition) 1 Computational Mechanics 1 Applied Mathematics Letters 1 Journal of Non-Equilibrium Thermodynamics 1 SIAM Journal on Mathematical Analysis 1 Archive of Applied Mechanics 1 Computational Optimization and Applications 1 Calculus of Variations and Partial Differential Equations 1 NoDEA. Nonlinear Differential Equations and Applications 1 Discrete and Continuous Dynamical Systems 1 European Series in Applied and Industrial Mathematics (ESAIM): Control, Optimization and Calculus of Variations 1 Nonlinear Dynamics 1 Journal of Applied Mechanics and Technical Physics 1 ZAMM. Zeitschrift für Angewandte Mathematik und Mechanik 1 Communications in Nonlinear Science and Numerical Simulation 1 Communications in Contemporary Mathematics 1 Archives of Computational Methods in Engineering 1 International Journal of Fracture 1 Nonlinear Oscillations 1 Optimization Letters 1 International Journal of Structural Stability and Dynamics 1 Evolution Equations and Control Theory 1 Bollettino dell’Unione Matematica Italiana
all top 5
#### Cited in 24 Fields
244 Mechanics of deformable solids (74-XX) 25 Partial differential equations (35-XX) 22 Calculus of variations and optimal control; optimization (49-XX) 14 Linear and multilinear algebra; matrix theory (15-XX) 12 Classical thermodynamics, heat transfer (80-XX) 7 Fluid mechanics (76-XX) 5 Integral equations (45-XX) 5 Numerical analysis (65-XX) 3 Real functions (26-XX) 3 Operator theory (47-XX) 2 History and biography (01-XX) 2 Group theory and generalizations (20-XX) 2 Functions of a complex variable (30-XX) 2 Ordinary differential equations (34-XX) 2 Differential geometry (53-XX) 2 Computer science (68-XX) 2 Optics, electromagnetic theory (78-XX) 2 Statistical mechanics, structure of matter (82-XX) 2 Operations research, mathematical programming (90-XX) 1 Dynamical systems and ergodic theory (37-XX) 1 Functional analysis (46-XX) 1 Mechanics of particles and systems (70-XX) 1 Systems theory; control (93-XX) 1 Information and communication theory, circuits (94-XX)
#### Wikidata Timeline
The data are displayed as stored in Wikidata under a Creative Commons CC0 License. Updates and corrections should be made in Wikidata.
| 2021-01-18T17:39:15 |
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https://alldimensions.fandom.com/wiki/Forostone
|
## FANDOM
2,887 Pages
A Forostone is the exact core of a Dimension/Alter Reality, holding 30-55% of a dimension's mass.
## Foroverse
A Foroverse is a strange universe 3 dimensions lower than the Forostone it is in, and is 0.005% of the diameter of the Forostone. It is the least dense part of the Forostone, It is $\pi^{10^{6}}$ times less dense than the space between the Forostone and the Foroverse.
Community content is available under CC-BY-SA unless otherwise noted.
| 2020-07-12T08:02:41 |
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https://pdglive.lbl.gov/DataBlock.action?node=S126YTC
|
# top Yukawa coupling INSPIRE search
VALUE CL% DOCUMENT ID TECN COMMENT
$\bf{<1.7}$ 95 1
2020 C
CMS ${{\mathit p}}{{\mathit p}}$ , 13 TeV
• • • We do not use the following data for averages, fits, limits, etc. • • •
$<1.67$ 95 2
2019 BY
CMS ${{\mathit p}}{{\mathit p}}$ , 13 TeV
$<2.1$ 95 3
2018 BU
CMS ${{\mathit p}}{{\mathit p}}$ , 13 TeV
1 SIRUNYAN 2020C search for the production of four top quarks with same-sign and multilepton final states with 137 fb${}^{-1}$ ${{\mathit p}}{{\mathit p}}$ collision data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The results constraint the ratio of the top quark Yukawa coupling ${{\mathit y}_{{t}}}$ to its the Standard Model by comparing to the central value of a theoretical prediction (see their Refs. [1-2]), yielding $\vert {{\mathit y}_{{t}}}/{{\mathit y}_{{t}}^{SM}}\vert$ $<$ 1.7 at 95$\%$ CL. See their Fig. 5.
2 SIRUNYAN 2019BY measure the top quark Yukawa coupling from ${{\mathit t}}{{\overline{\mathit t}}}$ kinematic distributions, the invariant mass of the top quark pair and the rapidity difference between ${{\mathit t}}$ and ${{\overline{\mathit t}}}$, in the ${{\mathit \ell}}$+jets final state with 35.8 fb${}^{-1}$ ${{\mathit p}}{{\mathit p}}$ collision data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The results constraint the ratio of the top quark Yukawa coupling to its the Standard Model to be $1.07$ ${}^{+0.34}_{-0.43}$ with an upper limit of 1.67 at 95$\%$ CL (see their Table III).
3 SIRUNYAN 2018BU search for the production of four top quarks with same-sign and multilepton final states with 35.9 fb${}^{-1}$ ${{\mathit p}}{{\mathit p}}$ collision data at $\mathit E_{{\mathrm {cm}}}$ = 13 TeV. The results constraint the ratio of the top quark Yukawa coupling ${{\mathit y}_{{t}}}$ to its the Standard Model by comparing to the central value of a theoretical prediction (see their Ref. [16]), yielding $\vert {{\mathit y}_{{t}}}/{{\mathit y}_{{t}}^{SM}}\vert$ $<$ 2.1 at 95$\%$ CL.
References:
SIRUNYAN 2020C
EPJ C80 75 Search for production of four top quarks in final states with same-sign or multiple leptons in proton-proton collisions at $\sqrt{s}=$ 13 TeV
SIRUNYAN 2019BY
PR D100 072007 Measurement of the top quark Yukawa coupling from $\mathrm{t\bar{t}}$ kinematic distributions in the lepton+jets final state in proton-proton collisions at $\sqrt{s} =$ 13 TeV
SIRUNYAN 2018BU
EPJ C78 140 Search for standard model production of four top quarks with same-sign and multilepton final states in proton?proton collisions at $\sqrt{s} = 13\,\text {TeV}$
| 2021-02-28T19:36:32 |
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https://par.nsf.gov/biblio/10392983-shocks-very-local-interstellar-medium
|
This content will become publicly available on June 1, 2023
Shocks in the Very Local Interstellar Medium
Abstract Large-scale disturbances generated by the Sun’s dynamics first propagate through the heliosphere, influence the heliosphere’s outer boundaries, and then traverse and modify the very local interstellar medium (VLISM). The existence of shocks in the VLISM was initially suggested by Voyager observations of the 2-3 kHz radio emissions in the heliosphere. A couple of decades later, both Voyagers crossed the definitive edge of our heliosphere and became the first ever spacecraft to sample interstellar space. Since Voyager 1’s entrance into the VLISM, it sampled electron plasma oscillation events that indirectly measure the medium’s density, increasing as it moves further away from the heliopause. Some of the observed electron oscillation events in the VLISM were associated with the local heliospheric shock waves. The observed VLISM shocks were very different than heliospheric shocks. They were very weak and broad, and the usual dissipation via wave-particle interactions could not explain their structure. Estimates of the dissipation associated with the collisionality show that collisions can determine the VLISM shock structure. According to theory and models, the existence of a bow shock or wave in front of our heliosphere is still an open question as there are no direct observations yet. This paper reviews the outstanding more »
Authors:
; ; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
Publication Date:
NSF-PAR ID:
10392983
Journal Name:
Space Science Reviews
Volume:
218
Issue:
4
ISSN:
0038-6308
5. Voyager 1 (V1) has been exploring the heliospheric boundary layer in the very local interstellar medium (VLISM) since August 2012. This study presents a broadband multi-scale analysis of VLSIM magnetic turbulence between 124 and 144 au from the Sun, as observed by V1 during the period from 2013.36 to 2019.0. We use high resolution 48-s data and show the existence of physically relevant fluctuations on scales as small as the ion inertial length in the thermal plasma. In the fine-scale regime below $\sim 10^{-3}$ au, an evidence is provided of the intermittent turbulence cascade which retains a significant level of magnetic compressibility. Observed fluctuations are compatible with the presence of filamentary structures and sawtooth-like waveforms of mixed compressible/transverse nature. A striking example of small-scale enhanced turbulence (wavelengths in the range of $\sim 1-10^3$ ion inertial lengths) is observed in front of the shock wave that overtook V1 on DOY 237, 2014 at 140 au from the Sun. This event starts on DOY 178, 2014, and suggests the presence of an ion foreshock. Besides, small-scale intermittency has been growing smoothly since 2018.5. Our analysis suggests that local processes are contributing to the production of turbulence in this regime. We identified themore »
| 2023-03-22T12:41:13 |
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https://indico.bnl.gov/event/10050/
|
***ATTENTION Indico Users***
Important changes to user logins are coming to Indico at BNL.
This seminar will be broadcast via zoom. You can join using the URL https://bnl.zoomgov.com/j/1618659309?pwd=Unc4QTY4QUlBUXoyY1lEeGRMSDh2Zz09.
Nuclear Physics Seminars at BNL
Jerome Jung, "Soft dielectron production in pp collisions at sqrt(s)=13 TeV with ALICE"
US/Eastern
Description
The production of soft photons in small systems was extensively
studied in fixed-target experiments at beam momenta ranging from 10.5 to 450 GeV/c. Most experiments reported an excess of soft photons compared with the expectation from hadron decays that could not be explained by initial- and final-state bremsstrahlung. The emergence of a photon excess in a transverse momentum (pT) range far below 0.2 GeV/c was dubbed the soft-photon puzzle. At the Intersecting Storage Rings (ISR) at CERN, also an excess of dielectrons had been measured at low invariant mass and small pair pT_ee in pp collisions at sqrt(s) = 63 GeV. In ALICE the reconstruction efficiency of low-pT electrons can be increased by reducing the magnetic field of the central barrel solenoid. This allows a better electron background rejection and simultaneously enables the investigation of a kinematic domain at low dielectron invariant mass m_ee and pair transverse momentum pT_ee similar to that of the ISR experiment, which was previously inaccessible at the LHC.
In this talk, a measurement of dielectron production in proton-proton (pp) collisions at sqrt(s) = 13 TeV, recorded with the ALICE detector at the CERN LHC, will be presented. The data set was taken with a reduced magnetic solenoid field of 0.2 T. The cross section for dielectron production is studied as a function of mee, pT_ee, and event multiplicity dNch/deta. Comparison of the measured dielectron yield to the hadronic decay cocktail at 0.15<m_ee <0.6 GeV/c2 and for pT <0.4 GeV/c indicates an enhancement of soft dielectrons, reminiscent of the ’anomalous’ soft-photon and -dilepton excess in hadron-hadron collisions. Acceptance-corrected excess spectra are extracted and compared with calculations of dielectron production from hadronic bremsstrahlung and thermal radiation within a hadronic many-body approach.
Organized by
Takao Sakaguchi
| 2022-01-18T21:51:06 |
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http://www.popflock.com/learn?s=Coupled_mode_theory
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Coupled Mode Theory
Get Coupled Mode Theory essential facts below. View Videos or join the Coupled Mode Theory discussion. Add Coupled Mode Theory to your PopFlock.com topic list for future reference or share this resource on social media.
Coupled Mode Theory
Coupled mode theory (CMT) is a perturbational approach for analyzing the coupling of vibrational systems (mechanical, optical, electrical, etc.) in space or in time. Coupled mode theory allows a wide range of devices and systems to be modeled as one or more coupled resonators. In optics, such systems include laser cavities, photonic crystal slabs, metamaterials, and ring resonators.
## History
Coupled mode theory first arose in the 1950s in the works of Miller on microwave transmission lines,[1] Pierce on electron beams,[2] and Gould on backward wave oscillators.[3] This put in place the mathematical foundations for the modern formulation expressed by H. A. Haus et al. for optical waveguides.[4][5]
In the late 1990s and early 2000s, the field of nanophotonics has revitalized interest in coupled mode theory. Coupled mode theory has been used to account for the Fano resonances in photonic crystal slabs[6] and has also been modified to account for optical resonators with non-orthogonal modes.[7]
## Overview
The oscillatory systems to which coupled mode theory applies are described by second order partial differential equations (e.g. a mass on a spring, an RLC circuit). CMT allows the second order differential equation to be expressed as one or more uncoupled first order differential equations. The following assumptions are generally made with CMT:
• Linearity
• Time-reversal symmetry
• Time-invariance
• Weak mode coupling (small perturbation of uncoupled modes)
• Energy conservation
## Formulation
The formulation of the coupled mode theory is based on the development of the solution to an electromagnetic problem into modes. Most of the time it is eigenmodes which are taken in order to form a complete base. The choice of the base and the adoption of certain hypothesis like parabolic approximation differs from formulation to formulation. The classification proposed by [8] of the different formulation is as follows:
1. The choice of starting differential equation. some of the coupled mode theories are derived directly from the Maxwell differential equations [9][10] (here) although others use simplifications in order to obtain a Helmholtz equation.
2. The choice of principle to derive the equations of the CMT. Either the reciprocity theorem [9][10] or the variational principle have been used.
3. The choice of orthogonality product used to establish the eigenmode base. Some references use the unconjugated form [9] and others the complex-conjugated form.[10]
4. Finally, the choice of the form of the equation, either vectorial [9][10] or scalar.
When n modes of an electromagnetic wave propagate through a media in the direction z without loss the power transported by each mode is described by a modal power Pm. At a given frequency ?.
${\displaystyle P^{\omega }(z)=\sum _{m}^{n}P_{m}^{\omega }(z)={\frac {1}{4}}\sum _{m}^{n}N_{m}^{\omega }\left|a_{m}^{\omega }(z)\right|^{2}\,\!}$
where Nm is the norm of the mth mode and am is the modal amplitude.
## References
1. ^ S.E.Miller,"Coupled wave theory and waveguide applications.", Bell System Technical Journal, 1954
2. ^ J. R. Pierce, "Coupling of modes of propagations", Journal of Applied Physics, 25, 1954
3. ^ R.W. Gould, "A coupled mode description of the backward-wave oscillator and the Kompfner dip condition" I.R.E. Trans. Electron Devices, vol. PGED-2, pp. 37-42, 1955.
4. ^ Haus, H., et al. "Coupled-mode theory of optical waveguides." Journal of Lightwave Technology 5.1 (1987): 16-23.
5. ^ H. A. Haus, W. P. Huang. "Coupled Mode Theory."Proceedings of the IEEE, Vol 19, No 10, October 1991.
6. ^ S. Fan, W. Suh, J. Joannopoulos, "Temporal coupled-mode theory for the Fano resonance in optical resonators," JOSA A, vol. 20, no. 3, pp. 569-572, 2003.
7. ^ W. Suh, Z. Wang, and S. Fan, "Temporal coupled-mode theory and the presence of non-orthogonal modes in lossless multimode cavities," Quantum Electronics, IEEE Journal of, vol. 40, no. 10, pp. 1511-1518, 2004
8. ^ Barybin and Dmitriev,"Modern Electrodynamics and Coupled-mode theory",2002
9. ^ a b c d Hardy and Streifer, "Coupled mode theory of parallel waveguides", Journal of Lightwave Technology,1985
10. ^ a b c d A. W. Snyder and J. D. Love, "Optical waveguide Theory",Chapman and Hall, 1983
## See also
This article uses material from the Wikipedia page available here. It is released under the Creative Commons Attribution-Share-Alike License 3.0.
| 2020-11-29T02:40:10 |
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https://zbmath.org/authors/?q=ai:sigmund.karl
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## Sigmund, Karl
Compute Distance To:
Author ID: sigmund.karl Published as: Sigmund, Karl; Sigmund, K. External Links: MGP · Wikidata · GND · IdRef
Documents Indexed: 111 Publications since 1969, including 10 Books 10 Contributions as Editor Co-Authors: 58 Co-Authors with 68 Joint Publications 1,489 Co-Co-Authors
all top 5
### Co-Authors
52 single-authored 15 Schuster, Peter 14 Hofbauer, Josef 10 Nowak, Martin Andreas 7 Wolff, Robert 4 Dawson, John W. jun. 4 Hauert, Christoph 4 Traulsen, Arne 3 Brandt, Hannelore 3 Dieckmann, Ulf 3 Kurzhanskiĭ, Aleksandr Borisovich 3 Michor, Peter Wolfram 2 Aubin, Jean-Pierre 2 Beham, Bernhard 2 Boerlijst, Maarten C. 2 De Silva, Hannelore 2 Hilbe, Christian 2 Hlawka, Edmund 2 Menger, Karl 2 Sigmund, Anna Maria 1 Alt, Franz L. 1 Bauer, Walter 1 Binder, Christa 1 Brännström, Åke 1 Čap, Andreas 1 Debreu, Gérard 1 Demetrius, Lloyd A. 1 Denker, Manfred 1 Diekmann, Odo 1 Dierker, Egbert 1 El-Sedy, Esam. A. S. 1 Engelking, Ryszard 1 Enzensberger, Hans Magnus 1 Feichtinger, Hans Georg 1 Gaunersdorfer, Andrea 1 Golland, Louise Ahrndt 1 Gottlieb, Ramon 1 Grillenberger, Christian 1 Gruber, Peter Manfred 1 Haiden, Nina 1 Hauser, Herwig 1 Helmberg, Gilbert 1 Hildenbrand, Werner 1 Hofstadter, Douglas R. 1 Iwasa, Yoh 1 Jansen, Vincent A. A. 1 Koth, Maria 1 Lamel, Bernhard 1 Lee, Joung Hun 1 Merz, Philip 1 Metz, Johan A. Jacob 1 Mühlberger, Kurt 1 Reich, Ludwig 1 Saari, Donald Gene 1 Sabelis, Maurice W. 1 Sasaki, Tatsuya 1 Schachermayer, Walter 1 Schmetterer, Leopold 1 Schuder, P. 1 Schweizer, Berthold 1 Shigesada, Nanako 1 Sklar, Abe 1 Takeuchi, Yasuhiro 1 Teichmann, Josef 1 Teschl, Gerald 1 Uchida, Satoshi
all top 5
### Serials
9 Internationale Mathematische Nachrichten 8 The Mathematical Intelligencer 5 Theoretical Population Biology 4 Biological Cybernetics 4 Journal of Mathematical Biology 4 Journal of Theoretical Biology 3 Mathematical Biosciences 3 Mitteilungen der Deutschen Mathematiker-Vereinigung (DMV) 3 Bulletin of Mathematical Biology 3 Monatshefte für Mathematik 3 Proceedings of the National Academy of Sciences of the United States of America 2 Games and Economic Behavior 2 SIAM Journal on Applied Mathematics 2 Lecture Notes in Economics and Mathematical Systems 1 American Mathematical Monthly 1 Israel Journal of Mathematics 1 Journal of Mathematical Analysis and Applications 1 American Journal of Mathematics 1 Applied Mathematics and Computation 1 Compositio Mathematica 1 Gazette des Mathématiciens 1 Inventiones Mathematicae 1 Journal of Computational and Applied Mathematics 1 Journal of Differential Equations 1 Journal für die Reine und Angewandte Mathematik 1 Manuscripta Mathematica 1 Mathematical Systems Theory 1 Mathematische Zeitschrift 1 Proceedings of the American Mathematical Society 1 Transactions of the American Mathematical Society 1 Zeitschrift für Wahrscheinlichkeitstheorie und Verwandte Gebiete 1 Acta Applicandae Mathematicae 1 Applied Mathematics Letters 1 Annals of Operations Research 1 SIAM Review 1 Bulletin of the American Mathematical Society. New Series 1 Notices of the American Mathematical Society 1 Complexity 1 Documenta Mathematica 1 Discrete and Continuous Dynamical Systems. Series B 1 Lecture Notes in Mathematics 1 London Mathematical Society Student Texts 1 Proceedings of Symposia in Applied Mathematics 1 Science 1 Dynamic Games and Applications
all top 5
### Fields
42 Biology and other natural sciences (92-XX) 40 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 34 History and biography (01-XX) 24 Dynamical systems and ergodic theory (37-XX) 14 General and overarching topics; collections (00-XX) 13 Measure and integration (28-XX) 11 Ordinary differential equations (34-XX) 7 General topology (54-XX) 7 Probability theory and stochastic processes (60-XX) 3 Mathematical logic and foundations (03-XX) 3 Classical thermodynamics, heat transfer (80-XX) 3 Operations research, mathematical programming (90-XX) 3 Systems theory; control (93-XX) 2 Number theory (11-XX) 2 Calculus of variations and optimal control; optimization (49-XX) 2 Geometry (51-XX) 2 Global analysis, analysis on manifolds (58-XX) 1 Algebraic geometry (14-XX) 1 Linear and multilinear algebra; matrix theory (15-XX) 1 Statistics (62-XX) 1 Numerical analysis (65-XX) 1 Computer science (68-XX) 1 Mechanics of particles and systems (70-XX)
### Citations contained in zbMATH Open
78 Publications have been cited 3,266 times in 2,428 Documents Cited by Year
Evolutionary games and population dynamics. Zbl 0914.90287
Hofbauer, Josef; Sigmund, Karl
1998
Ergodic theory on compact spaces. Zbl 0328.28008
Denker, Manfred; Grillenberger, Christian; Sigmund, Karl
1976
The theory of evolution and dynamical systems. Mathematical aspects of selection. Zbl 0678.92010
Hofbauer, Josef; Sigmund, Karl
1988
Evolutionary game dynamics. Zbl 1049.91025
Hofbauer, Josef; Sigmund, Karl
2003
The calculus of selfishness. Zbl 1189.91010
Sigmund, Karl
2010
Via freedom to coercion: the emergence of costly punishment. Zbl 1226.91010
Hauert, Christoph; Traulsen, Arne; Brandt, Hannelore; Nowak, Martin A.; Sigmund, Karl
2007
On dynamical systems with the specification property. Zbl 0286.28010
Sigmund, Karl
1974
Generic properties of invariant measures for Axiom A diffeomorphisms. Zbl 0193.35502
Sigmund, Karl
1970
Topological dynamics of transformations induced on the space of probability measures. Zbl 0314.54042
Bauer, Walter; Sigmund, Karl
1975
Adaptive dynamics and evolutionary stability. Zbl 0709.92015
Hofbauer, J.; Sigmund, K.
1990
The evolution of stochastic strategies in the prisoner’s dilemma. Zbl 0722.90092
Nowak, Martin; Sigmund, Karl
1990
Exploration dynamics in evolutionary games. Zbl 1202.91029
Traulsen, Arne; Hauert, Christoph; De Silva, Hannelore; Nowak, Martin A.; Sigmund, Karl
2009
Dynamical systems under constant organization. III: Cooperative and competitive behaviour of hypercycles. Zbl 0384.34029
Schuster, P.; Sigmund, K.; Wolff, R.
1979
On $$\omega$$-limits for competition between three species. Zbl 0418.92016
Schuster, P.; Sigmund, K.; Wolff, R.
1979
Evolution of extortion in iterated prisoner’s dilemma games. Zbl 1292.91031
Hilbe, Christian; Nowak, Martin A.; Sigmund, Karl
2013
On the stabilizing effect of predators and competitors on ecological communities. Zbl 0716.92024
Hofbauer, J.; Sigmund, K.
1989
The take-it-or-leave-it option allows small penalties to overcome social dilemmas. Zbl 1355.91045
Sasaki, Tatsuya; Brännström, Åke; Dieckmann, Ulf; Sigmund, Karl
2012
Selfregulation of behaviour in animal societies. I. Symmetric contests. Zbl 0465.92016
Schuster, Peter; Sigmund, Karl; Hofbauer, Josef; Wolff, Robert
1981
Selfregulation of behaviour in animal societies. II. Games between two populations without selfinteraction. Zbl 0465.92017
Schuster, Peter; Sigmund, Karl; Hofbauer, Josef; Wolff, Robert
1981
Dynamical systems under constant organization. I: Topological analysis of a family of non-linear differential equations - a model for catalytic hypercycles. Zbl 0384.34028
Schuster, P.; Sigmund, K.; Wolff, R.
1978
Automata, repeated games and noise. Zbl 0837.90140
Nowak, Martin A.; Sigmund, Karl; El-Sedy, Esam
1995
Polynucleotide evolution and branching processes. Zbl 0576.92020
Demetrius, Lloyd; Schuster, Peter; Sigmund, Karl
1985
Permanence for replicator equations. Zbl 0638.92012
Hofbauer, J.; Sigmund, K.
1987
On the space of invariant measures for hyperbolic flows. Zbl 0242.28014
Sigmund, Karl
1972
Shaken not stirred: On permanence in ecological communities. Zbl 0963.92505
Jansen, Vincent A. A.; Sigmund, Karl
1998
Adaptive dynamics of infectious diseases. In pursuit of virulence management. Zbl 1228.92050
2002
Mass action kinetics of selfreplication in flow reactors. Zbl 0464.92023
Schuster, Peter; Sigmund, Karl; Wolff, Robert
1980
Dynamical systems under constant organization. II: Homogeneous growth functions of degree p=2. Zbl 0411.34061
Hofbauer, J.; Schuder, P.; Sigmund, K.; Wolff, R.
1980
The competition of assessment rules for indirect reciprocity. Zbl 1406.91055
Uchida, Satoshi; Sigmund, Karl
2010
Game-dynamical aspects of the prisoner’s dilemma. Zbl 0673.90104
Nowak, Martin; Sigmund, Karl
1989
Partners or rivals? Strategies for the iterated prisoner’s dilemma. Zbl 1318.91029
Hilbe, Christian; Traulsen, Arne; Sigmund, Karl
2015
Selfregulation of behaviour in animal societies. III. Games between two populations with selfinteraction. Zbl 0465.92018
Schuster, Peter; Sigmund, Karl; Hofbauer, Josef; Gottlieb, Ramon; Merz, Philip
1981
Game dynamics, mixed strategies, and gradient systems. Zbl 0618.92013
Sigmund, Karl
1987
Competition and cooperation in catalytic selfreplication. Zbl 0448.92011
Hofbauer, J.; Schuster, P.; Sigmund, K.
1981
On the dynamics of asymmetric games. Zbl 0732.92031
Gaunersdorfer, Andrea; Hofbauer, Josef; Sigmund, Karl
1991
Permanence and uninvadability for deterministic population models. Zbl 0538.92018
Sigmund, K.; Schuster, P.
1984
Evolutionstheorie und dynamische Systeme. Mathematische Aspekte der Selektion. Zbl 0578.92015
Hofbauer, Josef; Sigmund, Karl
1984
Game dynamics in Mendelian populations. Zbl 0473.92015
Hofbauer, Josef; Schuster, Peter; Sigmund, Karl
1982
On minimal centers of attraction and generic points. Zbl 0354.54025
Sigmund, Karl
1977
Social control and the social contract: the emergence of sanctioning systems for collective action. Zbl 1214.91011
Sigmund, Karl; Hauert, Christoph; Traulsen, Arne; De Silva, Hannelore
2011
Time averages for unpredictable orbits of deterministic systems. Zbl 0778.58050
Sigmund, Karl
1992
On mixing measures for axiom A diffeomorphisms. Zbl 0225.28013
Sigmund, Karl
1973
The calculus of selfishness. Reprint of the 2010 hardback edition. Zbl 1338.91008
Sigmund, Karl
2016
On the connectedness of ergodic systems. Zbl 0365.28014
Sigmund, Karl
1977
Equal pay for all prisoners. Zbl 1044.91500
Boerlijst, Maarten C.; Nowak, Martin A.; Sigmund, Karl
1997
The dynamics of public goods. Zbl 1154.91398
Hauert, Christoph; Haiden, Nina; Sigmund, Karl
2004
Games of corruption: how to suppress illegal logging. Zbl 1412.91008
Lee, Joung-Hun; Sigmund, Karl; Dieckmann, Ulf; Iwasa, Yoh
2015
On the distribution of periodic points for $$\beta$$-shifts. Zbl 0333.58008
Sigmund, Karl
1976
A maximum principle for frequency dependent selection. Zbl 0617.92013
Sigmund, Karl
1987
The population dynamics of conflict and cooperation. Zbl 0907.92027
Sigmund, Karl
1998
Kolmogorov and population dynamics. Zbl 1222.01036
Sigmund, Karl
2007
The good, the bad and the discriminator – errors in direct and indirect reciprocity. Zbl 1446.91022
Brandt, Hannelore; Sigmund, Karl
2006
A survey of replicator equations. Zbl 0606.92001
Sigmund, Karl
1986
A philosopher’s mathematician: Hans Hahn and the Vienna circle. Zbl 0841.01012
Sigmund, Karl
1995
Results of a mathematical colloquium. (Ergebnisse eines Mathematischen Kolloquiums. Mit Beiträgen von J. W. Dawson jun., R. Engelking, W. Hildenbrand, Geleitwort von G. Debreu, Nachwort von F. Alt. Hrsg. von E. Dierker und K. Sigmund.) Zbl 0917.01024
Menger, Karl
1998
Exact thought in a demented time: Karl Menger and his Viennese Mathematical Colloquium. Zbl 1052.01522
Golland, Louise; Sigmund, Karl
2000
Ergodic averages for Axiom A diffeomorphisms. Zbl 0214.15901
Sigmund, K.
1971
On the prevalence of zero entropy. Zbl 0225.28012
Sigmund, Karl
1971
The maximum principle for replicator equations. Zbl 0576.92023
Sigmund, Karl
1985
Gradients for the evolution of bimatrix games. Zbl 0642.92010
Koth, Maria; Sigmund, Karl
1987
A mathematical model of the hypercycle. Zbl 0437.92015
Schuster, P.; Sigmund, K.
1980
On the time evolution of statistical states for Anosov systems. Zbl 0283.58012
Sigmund, Karl
1974
Normal and quasiregular points for automorphisms of the torus. Zbl 0297.28020
Sigmund, Karl
1975
Invasion dynamics of the finitely repeated prisoner’s dilemma. Zbl 0840.90143
Nowak, Martin A.; Sigmund, Karl
1995
The logic of reprobation: assessment and action rules for indirect reciprocation. Zbl 1464.92182
Brandt, Hannelore; Sigmund, Karl
2004
Random selection. A simple model based on linear birth and death processes. Zbl 0525.92013
Schuster, P.; Sigmund, K.
1984
Permanence and viability. Zbl 0659.93059
Aubin, Jean-Pierre; Sigmund, Karl
1988
Affine transformations on the space of probability measures. Zbl 0385.28010
Sigmund, Karl
1978
Leray in Edelbach. Zbl 1189.01064
Sigmund, Anna Maria; Michor, Peter; Sigmund, Karl
2005
Introduction to evolutionary game theory. Zbl 1241.91021
Sigmund, Karl
2011
Random selection and the neutral theory. Sources of stochasticity in replication. Zbl 0541.60092
Schuster, P.; Sigmund, K.
1984
Dynamics of macrosystems. Proceedings of a Workshop on the Dynamics of Macrosystems Held at the International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria, September 3-7, 1984. Zbl 0572.00024
1985
Permanence and heteroclinic cycles for ecological equations. Zbl 0665.92018
Sigmund, Karl
1987
Fixation probabilities for advantageous mutants: A note on multiplication and sampling. Zbl 0669.92008
Schuster, Peter; Sigmund, Karl
1989
Kepler in Eferding. Zbl 1055.01522
Sigmund, Karl
2001
Exact thinking in demented times. The Vienna Circle and the epic quest for the foundations of science. With a preface by Douglas Hofstadter. Translated from the German by the author. Revised edition of the German original. Zbl 1404.03003
Sigmund, Karl
2017
Obituary for Leopold Schmetterer (1919–2004). (Nachruf auf Leopold Schmetterer.) Zbl 1126.01018
Binder, Christa; Hlawka, Edmund; Sigmund, Karl
2006
Pictures at an exhibition. Zbl 1104.01318
Sigmund, Karl
2006
Exact thinking in demented times. The Vienna Circle and the epic quest for the foundations of science. With a preface by Douglas Hofstadter. Translated from the German by the author. Revised edition of the German original. Zbl 1404.03003
Sigmund, Karl
2017
The calculus of selfishness. Reprint of the 2010 hardback edition. Zbl 1338.91008
Sigmund, Karl
2016
Partners or rivals? Strategies for the iterated prisoner’s dilemma. Zbl 1318.91029
Hilbe, Christian; Traulsen, Arne; Sigmund, Karl
2015
Games of corruption: how to suppress illegal logging. Zbl 1412.91008
Lee, Joung-Hun; Sigmund, Karl; Dieckmann, Ulf; Iwasa, Yoh
2015
Evolution of extortion in iterated prisoner’s dilemma games. Zbl 1292.91031
Hilbe, Christian; Nowak, Martin A.; Sigmund, Karl
2013
The take-it-or-leave-it option allows small penalties to overcome social dilemmas. Zbl 1355.91045
Sasaki, Tatsuya; Brännström, Åke; Dieckmann, Ulf; Sigmund, Karl
2012
Social control and the social contract: the emergence of sanctioning systems for collective action. Zbl 1214.91011
Sigmund, Karl; Hauert, Christoph; Traulsen, Arne; De Silva, Hannelore
2011
Introduction to evolutionary game theory. Zbl 1241.91021
Sigmund, Karl
2011
The calculus of selfishness. Zbl 1189.91010
Sigmund, Karl
2010
The competition of assessment rules for indirect reciprocity. Zbl 1406.91055
Uchida, Satoshi; Sigmund, Karl
2010
Exploration dynamics in evolutionary games. Zbl 1202.91029
Traulsen, Arne; Hauert, Christoph; De Silva, Hannelore; Nowak, Martin A.; Sigmund, Karl
2009
Via freedom to coercion: the emergence of costly punishment. Zbl 1226.91010
Hauert, Christoph; Traulsen, Arne; Brandt, Hannelore; Nowak, Martin A.; Sigmund, Karl
2007
Kolmogorov and population dynamics. Zbl 1222.01036
Sigmund, Karl
2007
The good, the bad and the discriminator – errors in direct and indirect reciprocity. Zbl 1446.91022
Brandt, Hannelore; Sigmund, Karl
2006
Obituary for Leopold Schmetterer (1919–2004). (Nachruf auf Leopold Schmetterer.) Zbl 1126.01018
Binder, Christa; Hlawka, Edmund; Sigmund, Karl
2006
Pictures at an exhibition. Zbl 1104.01318
Sigmund, Karl
2006
Leray in Edelbach. Zbl 1189.01064
Sigmund, Anna Maria; Michor, Peter; Sigmund, Karl
2005
The dynamics of public goods. Zbl 1154.91398
Hauert, Christoph; Haiden, Nina; Sigmund, Karl
2004
The logic of reprobation: assessment and action rules for indirect reciprocation. Zbl 1464.92182
Brandt, Hannelore; Sigmund, Karl
2004
Evolutionary game dynamics. Zbl 1049.91025
Hofbauer, Josef; Sigmund, Karl
2003
Adaptive dynamics of infectious diseases. In pursuit of virulence management. Zbl 1228.92050
2002
Kepler in Eferding. Zbl 1055.01522
Sigmund, Karl
2001
Exact thought in a demented time: Karl Menger and his Viennese Mathematical Colloquium. Zbl 1052.01522
Golland, Louise; Sigmund, Karl
2000
Evolutionary games and population dynamics. Zbl 0914.90287
Hofbauer, Josef; Sigmund, Karl
1998
Shaken not stirred: On permanence in ecological communities. Zbl 0963.92505
Jansen, Vincent A. A.; Sigmund, Karl
1998
The population dynamics of conflict and cooperation. Zbl 0907.92027
Sigmund, Karl
1998
Results of a mathematical colloquium. (Ergebnisse eines Mathematischen Kolloquiums. Mit Beiträgen von J. W. Dawson jun., R. Engelking, W. Hildenbrand, Geleitwort von G. Debreu, Nachwort von F. Alt. Hrsg. von E. Dierker und K. Sigmund.) Zbl 0917.01024
Menger, Karl
1998
Equal pay for all prisoners. Zbl 1044.91500
Boerlijst, Maarten C.; Nowak, Martin A.; Sigmund, Karl
1997
Automata, repeated games and noise. Zbl 0837.90140
Nowak, Martin A.; Sigmund, Karl; El-Sedy, Esam
1995
A philosopher’s mathematician: Hans Hahn and the Vienna circle. Zbl 0841.01012
Sigmund, Karl
1995
Invasion dynamics of the finitely repeated prisoner’s dilemma. Zbl 0840.90143
Nowak, Martin A.; Sigmund, Karl
1995
Time averages for unpredictable orbits of deterministic systems. Zbl 0778.58050
Sigmund, Karl
1992
On the dynamics of asymmetric games. Zbl 0732.92031
Gaunersdorfer, Andrea; Hofbauer, Josef; Sigmund, Karl
1991
Adaptive dynamics and evolutionary stability. Zbl 0709.92015
Hofbauer, J.; Sigmund, K.
1990
The evolution of stochastic strategies in the prisoner’s dilemma. Zbl 0722.90092
Nowak, Martin; Sigmund, Karl
1990
On the stabilizing effect of predators and competitors on ecological communities. Zbl 0716.92024
Hofbauer, J.; Sigmund, K.
1989
Game-dynamical aspects of the prisoner’s dilemma. Zbl 0673.90104
Nowak, Martin; Sigmund, Karl
1989
Fixation probabilities for advantageous mutants: A note on multiplication and sampling. Zbl 0669.92008
Schuster, Peter; Sigmund, Karl
1989
The theory of evolution and dynamical systems. Mathematical aspects of selection. Zbl 0678.92010
Hofbauer, Josef; Sigmund, Karl
1988
Permanence and viability. Zbl 0659.93059
Aubin, Jean-Pierre; Sigmund, Karl
1988
Permanence for replicator equations. Zbl 0638.92012
Hofbauer, J.; Sigmund, K.
1987
Game dynamics, mixed strategies, and gradient systems. Zbl 0618.92013
Sigmund, Karl
1987
A maximum principle for frequency dependent selection. Zbl 0617.92013
Sigmund, Karl
1987
Gradients for the evolution of bimatrix games. Zbl 0642.92010
Koth, Maria; Sigmund, Karl
1987
Permanence and heteroclinic cycles for ecological equations. Zbl 0665.92018
Sigmund, Karl
1987
A survey of replicator equations. Zbl 0606.92001
Sigmund, Karl
1986
Polynucleotide evolution and branching processes. Zbl 0576.92020
Demetrius, Lloyd; Schuster, Peter; Sigmund, Karl
1985
The maximum principle for replicator equations. Zbl 0576.92023
Sigmund, Karl
1985
Dynamics of macrosystems. Proceedings of a Workshop on the Dynamics of Macrosystems Held at the International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria, September 3-7, 1984. Zbl 0572.00024
1985
Permanence and uninvadability for deterministic population models. Zbl 0538.92018
Sigmund, K.; Schuster, P.
1984
Evolutionstheorie und dynamische Systeme. Mathematische Aspekte der Selektion. Zbl 0578.92015
Hofbauer, Josef; Sigmund, Karl
1984
Random selection. A simple model based on linear birth and death processes. Zbl 0525.92013
Schuster, P.; Sigmund, K.
1984
Random selection and the neutral theory. Sources of stochasticity in replication. Zbl 0541.60092
Schuster, P.; Sigmund, K.
1984
Game dynamics in Mendelian populations. Zbl 0473.92015
Hofbauer, Josef; Schuster, Peter; Sigmund, Karl
1982
Selfregulation of behaviour in animal societies. I. Symmetric contests. Zbl 0465.92016
Schuster, Peter; Sigmund, Karl; Hofbauer, Josef; Wolff, Robert
1981
Selfregulation of behaviour in animal societies. II. Games between two populations without selfinteraction. Zbl 0465.92017
Schuster, Peter; Sigmund, Karl; Hofbauer, Josef; Wolff, Robert
1981
Selfregulation of behaviour in animal societies. III. Games between two populations with selfinteraction. Zbl 0465.92018
Schuster, Peter; Sigmund, Karl; Hofbauer, Josef; Gottlieb, Ramon; Merz, Philip
1981
Competition and cooperation in catalytic selfreplication. Zbl 0448.92011
Hofbauer, J.; Schuster, P.; Sigmund, K.
1981
Mass action kinetics of selfreplication in flow reactors. Zbl 0464.92023
Schuster, Peter; Sigmund, Karl; Wolff, Robert
1980
Dynamical systems under constant organization. II: Homogeneous growth functions of degree p=2. Zbl 0411.34061
Hofbauer, J.; Schuder, P.; Sigmund, K.; Wolff, R.
1980
A mathematical model of the hypercycle. Zbl 0437.92015
Schuster, P.; Sigmund, K.
1980
Dynamical systems under constant organization. III: Cooperative and competitive behaviour of hypercycles. Zbl 0384.34029
Schuster, P.; Sigmund, K.; Wolff, R.
1979
On $$\omega$$-limits for competition between three species. Zbl 0418.92016
Schuster, P.; Sigmund, K.; Wolff, R.
1979
Dynamical systems under constant organization. I: Topological analysis of a family of non-linear differential equations - a model for catalytic hypercycles. Zbl 0384.34028
Schuster, P.; Sigmund, K.; Wolff, R.
1978
Affine transformations on the space of probability measures. Zbl 0385.28010
Sigmund, Karl
1978
On minimal centers of attraction and generic points. Zbl 0354.54025
Sigmund, Karl
1977
On the connectedness of ergodic systems. Zbl 0365.28014
Sigmund, Karl
1977
Ergodic theory on compact spaces. Zbl 0328.28008
Denker, Manfred; Grillenberger, Christian; Sigmund, Karl
1976
On the distribution of periodic points for $$\beta$$-shifts. Zbl 0333.58008
Sigmund, Karl
1976
Topological dynamics of transformations induced on the space of probability measures. Zbl 0314.54042
Bauer, Walter; Sigmund, Karl
1975
Normal and quasiregular points for automorphisms of the torus. Zbl 0297.28020
Sigmund, Karl
1975
On dynamical systems with the specification property. Zbl 0286.28010
Sigmund, Karl
1974
On the time evolution of statistical states for Anosov systems. Zbl 0283.58012
Sigmund, Karl
1974
On mixing measures for axiom A diffeomorphisms. Zbl 0225.28013
Sigmund, Karl
1973
On the space of invariant measures for hyperbolic flows. Zbl 0242.28014
Sigmund, Karl
1972
Ergodic averages for Axiom A diffeomorphisms. Zbl 0214.15901
Sigmund, K.
1971
On the prevalence of zero entropy. Zbl 0225.28012
Sigmund, Karl
1971
Generic properties of invariant measures for Axiom A diffeomorphisms. Zbl 0193.35502
Sigmund, Karl
1970
all top 5
### Cited by 3,011 Authors
49 Nowak, Martin Andreas 36 Hofbauer, Josef 36 Sigmund, Karl 32 Cressman, Ross 31 Wang, Yuanshi 30 Traulsen, Arne 24 Oprocha, Piotr 22 Chen, Xiaojie 20 Ohtsuki, Hisashi 20 Wang, Long 17 Hauert, Christoph 17 Křivan, Vlastimil 17 Schuster, Peter 17 Wu, Hong 16 Schreiber, Sebastian J. 15 Broom, Mark 15 Perc, Matjaž 15 Tian, Xueting 14 Szolnoki, Attila 13 Kurokawa, Shun 13 Rand, David G. 13 Stadler, Peter F. 13 Takeuchi, Yasuhiro 12 Allen, Benjamin L. 12 Bomze, Immanuel M. 12 Lessard, Sabin 11 Ahmed, Elsayed 11 Hofbauer, Franz 11 Wang, Xianjia 11 Wang, Zhen 10 Ashwin, Peter 10 Boyle, Mike 10 Fu, Feng 10 Garay, József 10 Lu, Zhengyi 10 Pacheco, Jorge M. 10 Santos, Francisco C. 10 Sun, Wenxiang 10 Tao, Yi 10 van Veelen, Matthijs 10 Wu, Bin 10 Xia, Chengyi 10 Zhang, Boyu 9 Bratus, Alexander S. 9 Denker, Manfred 9 Gokhale, Chaitanya S. 9 He, Mingfeng 9 Jiang, Jifa 9 McAvoy, Alex 9 Mertikopoulos, Panayotis 9 Mukhamedov, Farruh Maksutovich 9 Pan, Qiuhui 9 Shi, Lei 9 Smith, Hal Leslie 9 Varandas, Paulo 9 Wang, Zhen 9 Ye, Xiangdong 8 Argasinski, Krzysztof 8 Bellomo, Nicola 8 Dieckmann, Ulf 8 Gyllenberg, Mats 8 Lind, Douglas A. 8 Liu, Linjie 8 Park, Junpyo 8 Radi, Davide 8 Rychtár, Jan 8 Sasaki, Tatsuya 8 Shaiju, A. J. 8 Shen, Chen 8 Souza, Max O. 7 Alsedà, Lluís 7 Auger, Pierre M. 7 Benaïm, Michel 7 Berger, Ulrich 7 Bischi, Gian-Italo 7 Chalub, Fabio A. C. C. 7 Das, Ruchi 7 Dercole, Fabio 7 Freedman, Herbert Irving 7 Hilbe, Christian 7 Huttegger, Simon M. 7 Imhof, Lorens A. 7 Karev, Georgiĭ Petrovich 7 Li, Mingchu 7 Liu, Chao 7 Masuda, Naoki 7 Mobilia, Mauro 7 Płatkowski, Tadeusz 7 Spirakis, Paul G. 7 Tanimoto, Jun 7 Tarniţǎ, Corina E. 7 Yamamoto, Kenichiro 6 Baake, Michael 6 Baigent, Stephen A. 6 Bauch, Chris T. 6 Blanchard, François 6 Bürger, Reinhard 6 Castro, Sofia B. S. D. 6 Champagnat, Nicolas 6 Chu, Chen ...and 2,911 more Authors
all top 5
### Cited in 326 Serials
281 Journal of Theoretical Biology 142 Journal of Mathematical Biology 100 Applied Mathematics and Computation 83 Chaos, Solitons and Fractals 79 Theoretical Population Biology 69 Bulletin of Mathematical Biology 66 Dynamic Games and Applications 61 Mathematical Biosciences 59 Ergodic Theory and Dynamical Systems 48 Games 45 Physica A 43 Journal of Mathematical Analysis and Applications 39 Transactions of the American Mathematical Society 37 Journal of Differential Equations 36 Monatshefte für Mathematik 35 Games and Economic Behavior 28 Israel Journal of Mathematics 27 Proceedings of the American Mathematical Society 27 International Journal of Bifurcation and Chaos in Applied Sciences and Engineering 27 Chaos 26 Physica D 22 Journal of Difference Equations and Applications 20 Journal of Statistical Physics 20 Physics Letters. A 19 Discrete and Continuous Dynamical Systems 18 International Journal of Game Theory 18 Nonlinear Analysis. Real World Applications 17 Dynamical Systems 16 Journal of Economic Theory 16 Topology and its Applications 16 Journal of Dynamics and Games 13 Theoretical Computer Science 13 International Journal of Modern Physics C 13 Discrete and Continuous Dynamical Systems. Series B 13 Journal of Biological Dynamics 12 Inventiones Mathematicae 12 Nonlinear Analysis. Theory, Methods & Applications. Series A: Theory and Methods 11 The Annals of Applied Probability 11 M$$^3$$AS. Mathematical Models & Methods in Applied Sciences 11 Proceedings of the National Academy of Sciences of the United States of America 11 Journal of Dynamics and Differential Equations 11 International Game Theory Review 11 Stochastics and Dynamics 10 Nonlinearity 10 Communications in Nonlinear Science and Numerical Simulation 10 Advances in Complex Systems 9 Computers & Mathematics with Applications 9 Communications in Mathematical Physics 9 Advances in Mathematics 9 Mathematische Zeitschrift 9 Journal of Economic Dynamics & Control 8 Acta Applicandae Mathematicae 8 Linear Algebra and its Applications 8 Stochastic Processes and their Applications 8 Journal of Nonlinear Science 8 Qualitative Theory of Dynamical Systems 8 SIAM Journal on Applied Dynamical Systems 8 Mathematical Biosciences and Engineering 8 The European Physical Journal B. Condensed Matter and Complex Systems 8 Mathematical Modelling of Natural Phenomena 7 Automatica 7 Journal of Computational and Applied Mathematics 7 The Journal of Mathematical Sociology 7 Theory and Decision 7 Complexity 7 Nonlinear Dynamics 7 Advances in Difference Equations 6 Biological Cybernetics 6 Physics Reports 6 The Mathematical Intelligencer 6 Systems & Control Letters 6 Annals of Operations Research 6 Journal de Mathématiques Pures et Appliquées. Neuvième Série 6 SIAM Journal on Mathematical Analysis 6 Acta Mathematica Sinica. English Series 6 Nonlinear Analysis. Theory, Methods & Applications 6 Proceedings of the Royal Society of London. A. Mathematical, Physical and Engineering Sciences 5 Applicable Analysis 5 Journal of the Franklin Institute 5 Mathematical Methods in the Applied Sciences 5 Mathematical Proceedings of the Cambridge Philosophical Society 5 Journal of Applied Probability 5 Journal of Computer and System Sciences 5 Zeitschrift für Wahrscheinlichkeitstheorie und Verwandte Gebiete 5 Mathematical Social Sciences 5 Mathematical and Computer Modelling 5 Japan Journal of Industrial and Applied Mathematics 5 European Journal of Operational Research 5 Abstract and Applied Analysis 5 New Journal of Physics 5 International Journal of Biomathematics 4 Rocky Mountain Journal of Mathematics 4 Bulletin de la Société Mathématique de France 4 Mathematics of Operations Research 4 Forum Mathematicum 4 Proceedings of the Royal Society of Edinburgh. Section A. Mathematics 4 Economic Theory 4 Differential Equations and Dynamical Systems 4 Discrete Dynamics in Nature and Society 4 Journal of Dynamical and Control Systems ...and 226 more Serials
all top 5
### Cited in 55 Fields
1,092 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 987 Biology and other natural sciences (92-XX) 704 Dynamical systems and ergodic theory (37-XX) 325 Ordinary differential equations (34-XX) 176 Probability theory and stochastic processes (60-XX) 147 General topology (54-XX) 139 Measure and integration (28-XX) 85 Partial differential equations (35-XX) 76 Computer science (68-XX) 69 Systems theory; control (93-XX) 54 Operations research, mathematical programming (90-XX) 53 Statistical mechanics, structure of matter (82-XX) 39 Combinatorics (05-XX) 34 Numerical analysis (65-XX) 32 Calculus of variations and optimal control; optimization (49-XX) 30 Operator theory (47-XX) 29 Number theory (11-XX) 27 Information and communication theory, circuits (94-XX) 25 Linear and multilinear algebra; matrix theory (15-XX) 24 Difference and functional equations (39-XX) 19 Statistics (62-XX) 15 History and biography (01-XX) 14 Mathematical logic and foundations (03-XX) 13 Topological groups, Lie groups (22-XX) 13 Functional analysis (46-XX) 13 Differential geometry (53-XX) 11 Global analysis, analysis on manifolds (58-XX) 10 General and overarching topics; collections (00-XX) 10 Integral equations (45-XX) 10 Mechanics of particles and systems (70-XX) 10 Quantum theory (81-XX) 9 Real functions (26-XX) 9 Functions of a complex variable (30-XX) 9 Manifolds and cell complexes (57-XX) 8 Convex and discrete geometry (52-XX) 8 Classical thermodynamics, heat transfer (80-XX) 6 Group theory and generalizations (20-XX) 5 Fluid mechanics (76-XX) 4 Several complex variables and analytic spaces (32-XX) 3 Algebraic geometry (14-XX) 3 Harmonic analysis on Euclidean spaces (42-XX) 3 Abstract harmonic analysis (43-XX) 2 Field theory and polynomials (12-XX) 2 Nonassociative rings and algebras (17-XX) 2 Approximations and expansions (41-XX) 2 Optics, electromagnetic theory (78-XX) 1 Commutative algebra (13-XX) 1 Associative rings and algebras (16-XX) 1 Potential theory (31-XX) 1 Special functions (33-XX) 1 Algebraic topology (55-XX) 1 Relativity and gravitational theory (83-XX) 1 Astronomy and astrophysics (85-XX) 1 Geophysics (86-XX) 1 Mathematics education (97-XX)
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https://pos.sissa.it/306/031/
|
Volume 306 - XII Multifrequency Behaviour of High Energy Cosmic Sources Workshop (MULTIF2017) - Astrophysics of High Energy Cosmic Sources
Future Ground-based Wide Field of View Air Shower Detectors
G. Di Sciascio
Full text: pdf
Pre-published on: 2018 February 03
Published on: 2018 May 30
Abstract
Extensive air shower (EAS) arrays directly sample the shower particles that reach the observation altitude.
They are wide field of view (FoV) detectors able of simultaneously and continuously viewing all the overhead sky. In fact, EAS arrays have an effective FoV of about 2 sr and operate with a duty cycle of $\sim$100\%.
This capability makes them well suited to study extended sources, such as the Galactic diffuse emission and measure the spectra of Galactic sources at the highest energies (near or beyond 100 TeV).
Their sensitivity in the sub-TeV/TeV energy domain cannot compete with that of Cherenkov telescopes, but the wide FoV
is ideal to perform unbiased sky surveys, discover transients or explosive events (GRBs) and monitor variable or flaring sources such as Active Galactic Nuclei (AGN).
An EAS array is able to detect at the same time events induced by gammas and charged cosmic rays, thus studying the connession between these two messengers of the non-thermal Universe.
Therefore, these detectors are, by definition, multi-messenger instruments.
Wide FoV telescopes are crucial for a multi-messanger study of the Gravitational Wave events due to their capability to survey simultaneously all the large sky regions identified by LIGO and VIRGO, looking for a possibile correlated $\gamma$-ray emission.
In this contribution we summarize the scientific motivations which push the construction of new wide FoV detectors and introduce the future instruments currently under installation. Finally, we emphasize the need of an EAS array in the Southern hemisphere to monitor the Inner Galaxy and face a number of important open problems.
DOI: https://doi.org/10.22323/1.306.0031
Open Access
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
| 2020-06-04T18:38:57 |
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http://dlmf.nist.gov/28.32
|
# §28.32 Mathematical Applications
## §28.32(i) Elliptical Coordinates and an Integral Relationship
If the boundary conditions in a physical problem relate to the perimeter of an ellipse, then elliptical coordinates are convenient. These are given by
The two-dimensional wave equation
then becomes
The separated solutions can be obtained from the modified Mathieu’s equation (28.20.1) for and from Mathieu’s equation (28.2.1) for , where is the separation constant and .
This leads to integral equations and an integral relation between the solutions of Mathieu’s equation (setting , in (28.32.3)).
Let be a solution of Mathieu’s equation (28.2.1) and be a solution of
Also let be a curve (possibly improper) such that the quantity
approaches the same value when tends to the endpoints of . Then
defines a solution of Mathieu’s equation, provided that (in the case of an improper curve) the integral converges with respect to uniformly on compact subsets of .
Kernels can be found, for example, by separating solutions of the wave equation in other systems of orthogonal coordinates. See Schmidt and Wolf (1979).
## §28.32(ii) Paraboloidal Coordinates
The general paraboloidal coordinate system is linked with Cartesian coordinates via
where is a parameter, , , and . When the Helmholtz equation
28.32.8
is separated in this system, each of the separated equations can be reduced to the Whittaker–Hill equation (28.31.1), in which are separation constants. Two conditions are used to determine . The first is the -periodicity of the solutions; the second can be their asymptotic form. For further information see Arscott (1967) for , and Urwin and Arscott (1970) for .
| 2013-06-19T05:20:02 |
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|
http://popflock.com/learn?s=Electrical_work
|
Electrical Work
Get Electrical Work essential facts below. View Videos or join the Electrical Work discussion. Add Electrical Work to your PopFlock.com topic list for future reference or share this resource on social media.
Electrical Work
Electric field work is the work performed by an electric field on a charged particle in its vicinity.
A charged particle located within the influence of an electric field experiences an interaction that is formally equivalent to other work by force fields in physics. The electric field performs work on the particle.[1] The work per unit of charge is defined by moving a negligible test charge between two points, and is expressed as the difference in electric potential at those points. The work can be done, for example, by electrochemical devices (electrochemical cells) or different metals junctions generating an electromotive force. The physical and mathematical formalism for electrical work is identical to that of mechanical work.
## Physical process
Particles that are free to move, if positively charged, normally tend towards regions of lower electric potential (net negative charge), while negatively charged particles tend to shift towards regions of higher potential (net positive charge).
Any movement of a positive charge into a region of higher potential requires external work to be done against the electric field, which is equal to the work that the electric field would do in moving that positive charge the same distance in the opposite direction. Similarly, it requires positive external work to transfer a negatively charged particle from a region of higher potential to a region of lower potential.
The electric force is a conservative force: work done by a static electric field is independent of the path taken by the charge. There is no change in the electric potential around any closed path; when returning to the starting point in a closed path, the net of the external work done is zero. The same holds for electric fields.
This is the basis of Kirchhoff's voltage law, one of the most fundamental laws governing electrical and electronic circuits, according to which the voltage gains and the drops in any electrical circuit always sum to zero.
The formalism for electric work has an equivalent format to that of mechanical work. The work per unit of charge, when moving a negligible test charge between two points, is defined as the voltage between those points.
${\displaystyle W=Q\int _{a}^{b}\mathbf {E} \cdot \,d\mathbf {r} =Q\int _{a}^{b}{\frac {\mathbf {F_{E}} }{Q}}\cdot \,d\mathbf {r} =\int _{a}^{b}\mathbf {F_{E}} \cdot \,d\mathbf {r} }$
where
Q is the electric charge of the particle, q, the unit charge
E is the electric field, which at a location is the force at that location divided by a unit ('test') charge
FE is the Coulomb (electric) force
r is the displacement
${\displaystyle \cdot }$ is the dot product
## Mathematical description
Given a charged object in empty space, Q+. To move q+ (with the same charge) closer to Q+ (starting from infinity, where the potential energy=0, for convenience), positive work would be performed. Mathematically:
${\displaystyle -{\frac {\partial U}{\partial \mathbf {r} }}=\mathbf {F} }$
In this case, U is the potential energy of q+. So, integrating and using Coulomb's Law for the force:
${\displaystyle U=-\int _{r_{0}}^{r}\mathbf {F} \cdot \,d\mathbf {r} =-\int _{r_{0}}^{r}{\frac {1}{4\pi \varepsilon _{0}}}{\frac {q_{1}q_{2}}{\mathbf {r^{2}} }}\cdot \,d\mathbf {r} ={\frac {q_{1}q_{2}}{4\pi \varepsilon _{0}}}\left({\frac {1}{r_{0}}}-{\frac {1}{r}}\right)+c}$
c is usually set to 0 and r(0) to infinity (making the 1/r(0) term=0) Now, use the relationship
${\displaystyle W=-\Delta U\!}$
To show that in this case if we start at infinity and move the charge to r,
${\displaystyle W={\frac {q_{1}q_{2}}{4\pi \varepsilon _{0}}}{\frac {1}{r}}}$
This could have been obtained equally by using the definition of W and integrating F with respect to r, which will prove the above relationship.
In the example both charges are positive; this equation is applicable to any charge configuration (as the product of the charges will be either positive or negative according to their (dis)similarity). If one of the charges were to be negative in the earlier example, the work taken to wrench that charge away to infinity would be exactly the same as the work needed in the earlier example to push that charge back to that same position. This is easy to see mathematically, as reversing the boundaries of integration reverses the sign.
### Uniform electric field
Where the electric field is constant (i.e. not a function of displacement, r), the work equation simplifies to:
${\displaystyle W=Q(\mathbf {E} \cdot \,\mathbf {r} )=\mathbf {F_{E}} \cdot \,\mathbf {r} }$
or 'force times distance' (times the cosine of the angle between them).
## Electric power
The electric power is the rate of energy transferred in an electric circuit. As a partial derivative, it is expressed as the change of work over time:
${\displaystyle P={\frac {\partial W}{\partial t}}={\frac {\partial QV}{\partial t}}}$,
where V is the voltage. Work is defined by:
${\displaystyle \delta W=\mathbf {F} \cdot \mathbf {v} \delta t,}$
Therefore
${\displaystyle {\frac {\partial W}{\partial t}}=\mathbf {F_{E}} \cdot \,\mathbf {v} }$
## References
1. ^ Debora M. Katz (1 January 2016). Physics for Scientists and Engineers: Foundations and Connections. Cengage Learning. pp. 1088-. ISBN 978-1-337-02634-5.
This article uses material from the Wikipedia page available here. It is released under the Creative Commons Attribution-Share-Alike License 3.0.
| 2021-01-24T16:12:38 |
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https://ftp.aimsciences.org/article/doi/10.3934/dcds.2016.36.3741
|
Article Contents
Article Contents
# On some two phase problem for compressible and compressible viscous fluid flow separated by sharp interface
• In this paper, we prove a local in time unique existence theorem for some two phase problem of compressible and compressible barotropic viscous fluid flow without surface tension in the $L_p$ in time and the $L_q$ in space framework with $2< p <\infty$ and $N< q <\infty$ under the assumption that the initial domain is a uniform $W^{2-1/q}_q$ domain in $\mathbb{R}^N (N\ge 2)$. After transforming a unknown time dependent domain to the initial domain by the Lagrangian transformation, we solve the problem by the contraction mapping principle with the maximal $L_p$-$L_q$ regularity of the generalized Stokes operator for the compressible viscous fluid flow with free boundary condition. The key step of our method is to prove the existence of $\mathcal{R}$-bounded solution operator to resolvent problem corresponding to linearized problem. The $\mathcal{R}$-boundedness combined with Weis's operator valued Fourier multiplier theorem implies the generation of analytic semigroup and the maximal $L_p$-$L_q$ regularity theorem.
Mathematics Subject Classification: Primary: 35K35; Secondary: 76N10.
Citation:
• [1] I. V. Denisova, Evolution of compressible and imcompressible fluids separated by a closed interface, Interface Free Bound., 2 (2000), 283-312.doi: 10.4171/IFB/21. [2] I. V. Denisova and V. A. Solonnikov, Classical solvability of a problem on the motion of an isolated mass of a compressible liquid, St. Petersburg Math. J., 14 (2003), 53-74. [3] I. V. Denisova and V. A. Solonnikov, Classical solvability of a model problem in a half-space, related to the motion of an isolated mass of a compressible fluid, J. Math. Sci., 115 (2003), 2753-2765.doi: 10.1023/A:1023365718404. [4] R. Denk, M. Hieber and J. Prüß, $\mathcalR$-boundedness, Fourier multiplier and problems of elliptic and parabolic type, Memories of AMS., 166 (2003), viii+114 pp.doi: 10.1090/memo/0788. [5] Y. Enomoto, L. v. Below and Y. Shibata, On some free boundary problem for a compressible barotopic viscous fluid flow, Ann Univ Ferrara, 60 (2014), 55-89.doi: 10.1007/s11565-013-0194-8. [6] Y. Enomoto and Y. Shibata, On the $\mathcalR$-sectoriality and its application to some mathematical study of the viscous compressible fluids, Funkcial. Ekvac., 56 (2013), 441-505.doi: 10.1619/fesi.56.441. [7] D. Götz and Y. Shibata, On the $\mathcalR$-boundedness of the solution operators in the study of the compressible viscous fluid with free boundary condition, Asymptotic Analysis, 90 (2014), 207-236.doi: 10.3233/ASY-141238. [8] T. Kubo, Y. Shibata and K. Soga, On the $\mathcalR$-boundedness for the Two phase prolem: Compressible-incompressible model prolem, Boundary Value Problems, 2014 (2014), 33p.doi: 10.1186/s13661-014-0141-3. [9] P. Scchi and A. Valli, A free boundary problem for compressible viscous fluid, J. Reine Angew, Math., 341 (1983), 1-31.doi: 10.1515/crll.1983.341.1. [10] Y. Shibata and S. Shimizu, On the $L_p$-$L_q$ maximal regularity of the Neumann problem for the Stokes equations in a bounded domain, J.Reine Angew. Math., 615 (2008), 157-209.doi: 10.1515/CRELLE.2008.013. [11] Y. Shibata and K. Tanaka, On a resolvent problem for the linealized system from the dynamical system describing the compressible viscous fluid motion, Math. Mech. Appl. Sci., 27 (2004), 1579-1606.doi: 10.1002/mma.518. [12] V. A. Solonnikov and A. Tani, Free boundary problem for a viscous compressible flow with the surface tension, Constantin Carathéodory: An International Tribute (Ih. M. Rassias, ed.), Vol. 1,2, World Sci. Publishing, Teaneck, (1991), 1270-1303. [13] G. Ströhmer, About the resolvent of an operator from fluid dynamics, Math. Z., 194 (1987), 183-191.doi: 10.1007/BF01161967. [14] A. Tani, On the free boundary value problem for compressible viscous fluid motion, J. Math. Kyoto Univ., 21 (1981), 839-859. [15] A. Tani, Two-phase free boundary problem for compressible viscous fluid motion, J. Math. Kyoto Univ., 24 (1984), 243-267. [16] L. Weis, Operator-valued Fourier multiplier theorems and maximal $L_p$-regularity, Math. Ann., 319 (2001), 735-758.doi: 10.1007/PL00004457.
Open Access Under a Creative Commons license
| 2023-03-21T03:51:44 |
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https://www.zbmath.org/authors/?q=ai%3Amassey.william-a
|
# zbMATH — the first resource for mathematics
## Massey, William A.
Compute Distance To:
Author ID: massey.william-a Published as: Massey, W. A.; Massey, William A. External Links: MGP · Wikidata
Documents Indexed: 41 Publications since 1978
all top 5
#### Co-Authors
9 single-authored 13 Whitt, Ward 4 Hampshire, Robert C. 4 Mandelbaum, Avi 3 Baccelli, François Louis 3 Pender, Jamol 2 Eick, Stephen G. 2 Jennings, Otis B. 2 Wang, Qiong 1 Davis, Jimmie L. 1 Dean, Nathaniel 1 Duffield, Nick G. 1 Feldman, Zohar 1 Goodman, Jonathan B. 1 Harchol-Balter, Mor 1 Kelmans, Alexander K. 1 Lanning, Steve G. 1 Lih, Keh-Wei 1 Morrison, John A. 1 Raphael, Derrick 1 Reiman, Martin I. 1 Srinivasan, Raj 1 Srinivasan, Rengarajan 1 Towsley, Donald Fred 1 Walker, Erica N. 1 Winkler, Peter M. 1 Wright, Paul E.
all top 5
#### Serials
7 Queueing Systems 5 Journal of Applied Probability 4 Management Science 4 Mathematics of Operations Research 3 Probability in the Engineering and Informational Sciences 2 Operations Research 2 The Annals of Applied Probability 1 Advances in Applied Probability 1 Bell System Technical Journal 1 Journal of the Association for Computing Machinery 1 Theoretical Computer Science 1 Performance Evaluation 1 Statistics & Probability Letters 1
all top 5
#### Fields
32 Probability theory and stochastic processes (60-XX) 26 Operations research, mathematical programming (90-XX) 8 Computer science (68-XX) 2 General and overarching topics; collections (00-XX) 2 Special functions (33-XX) 2 Mathematics education (97-XX) 1 Combinatorics (05-XX) 1 Ordinary differential equations (34-XX) 1 Functional analysis (46-XX) 1 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 1 Information and communication theory, circuits (94-XX)
#### Citations contained in zbMATH
35 Publications have been cited 617 times in 345 Documents Cited by Year
Strong approximation for Markovian service networks. Zbl 0911.90167
Mandelbaum, Avi; Massey, William A.; Reiman, Martin I.
1998
Strong approximations for time-dependent queues. Zbl 0834.60096
Mandelbaum, Avi; Massey, William A.
1995
Networks of infinite-server queues with nonstationary Poisson input. Zbl 0778.60068
Massey, William A.; Whitt, Ward
1993
The physics of the $$M_ t/G/\infty$$ queue. Zbl 0781.60086
Eick, Stephen G.; Massey, William A.; Whitt, Ward
1993
Server staffing to meet time-varying demand. Zbl 0880.90052
Jennings, Otis B.; Mandelbaum, Avishai; Massey, William A.; Whitt, Ward
1996
Staffing of time-varying queues to achieve time-stable performance. Zbl 1232.90275
Feldman, Zohar; Mandelbaum, Avishai; Massey, William A.; Whitt, Ward
2008
Stochastic orderings for Markov processes on partially ordered spaces. Zbl 0622.60098
Massey, William A.
1987
$$M_ t/G/\infty$$ queues with sinusoidal arrival rates. Zbl 0773.60086
Eick, Stephen G.; Massey, William A.; Whitt, Ward
1993
Uniform acceleration expansions for Markov chains with time-varying rates. Zbl 0937.60066
Massey, William A.; Whitt, Ward
1998
Gaussian skewness approximation for dynamic rate multi-server queues with abandonment. Zbl 1285.60091
Massey, William A.; Pender, Jamol
2013
An analysis of the modified offered-load approximation for the nonstationary Erlang loss model. Zbl 0812.60082
Massey, William A.; Whitt, Ward
1994
Asymptotic analysis of the time dependent M/M/1 queue. Zbl 0567.60089
Massey, William A.
1985
Acyclic fork-join queueing networks. Zbl 0675.90033
Baccelli, François; Massey, William A.; Towsley, Don
1989
Unstable asymptotics for nonstationary queues. Zbl 0801.60087
Massey, William A.; Whitt, Ward
1994
A probabilistic generalization of Taylor’s theorem. Zbl 0765.60032
Massey, William A.; Whitt, Ward
1993
Approximating and stabilizing dynamic rate Jackson networks with abandonment. Zbl 1370.60178
Pender, Jamol; Massey, William A.
2017
Fluid and diffusion limits for transient sojourn times of processor sharing queues with time varying rates. Zbl 1117.60083
Hampshire, Robert C.; Harchol-Balter, Mor; Massey, William A.
2006
The non-ergodic Jackson network. Zbl 0562.60096
Goodman, Jonathan B.; Massey, William A.
1984
Sensitivity to the service-time distribution in the nonstationary Erlang loss model. Zbl 0865.60091
Davis, Jimmie L.; Massey, William A.; Whitt, Ward
1995
A sample path analysis of the M/M/1 queue. Zbl 0683.60070
Baccelli, François; Massey, William A.
1989
A time-varying call center design via Lagrangian mechanics. Zbl 1173.90362
Hampshire, Robert C.; Jennings, Otis B.; Massey, William A.
2009
Peak congestion in multi-server service systems with slowly varying arrival rates. Zbl 0878.90044
Massey, William A.; Whitt, Ward
1997
Dynamic pricing to control loss systems with quality of service targets. Zbl 1173.90363
Hampshire, Robert C.; Massey, William A.; Wang, Qiong
2009
Stationary-process approximations for the nonstationary Erlang loss model. Zbl 0879.90099
Massey, William A.; Whitt, Ward
1996
A nonstationary offered-load model for packet networks. Zbl 1030.68650
Duffield, N. G.; Massey, W. A.; Whitt, W.
2001
Calculating exit times for series Jackson networks. Zbl 0626.60091
Massey, William A.
1987
An operator-analytic approach to the Jackson network. Zbl 0539.60093
Massey, William A.
1984
Open networks of queues: Their algebraic structure and estimating their transient behavior. Zbl 0528.60093
Massey, William A.
1984
Dynamic rate Erlang-A queues. Zbl 1408.60085
Massey, William A.; Pender, Jamol
2018
Calculation of steady-state probabilities for content of buffer with correlated inputs. Zbl 0389.94026
Massey, W. A.; Morrison, J. A.
1978
A note on the event horizon for a processor sharing queue. Zbl 1162.90395
Hampshire, Robert C.; Massey, William A.
2008
The spanning tree enumerating problem for digraphs. Zbl 0844.05053
Dean, Nathaniel; Kelmans, A. K.; Lih, Keh-Wei; Massey, William A.; Winkler, Peter
1995
Determining the exit time distribution for a closed cyclic network. Zbl 0789.60074
Baccelli, François; Massey, William A.; Wright, Paul E.
1994
Stochastic ordering for Markov processes on partially ordered spaces with applications to queueing networks. Zbl 0760.60088
Massey, William A.
1991
A family of bounds for the transient behavior of a Jackson network. Zbl 0602.60084
Massey, William A.
1986
Dynamic rate Erlang-A queues. Zbl 1408.60085
Massey, William A.; Pender, Jamol
2018
Approximating and stabilizing dynamic rate Jackson networks with abandonment. Zbl 1370.60178
Pender, Jamol; Massey, William A.
2017
Gaussian skewness approximation for dynamic rate multi-server queues with abandonment. Zbl 1285.60091
Massey, William A.; Pender, Jamol
2013
A time-varying call center design via Lagrangian mechanics. Zbl 1173.90362
Hampshire, Robert C.; Jennings, Otis B.; Massey, William A.
2009
Dynamic pricing to control loss systems with quality of service targets. Zbl 1173.90363
Hampshire, Robert C.; Massey, William A.; Wang, Qiong
2009
Staffing of time-varying queues to achieve time-stable performance. Zbl 1232.90275
Feldman, Zohar; Mandelbaum, Avishai; Massey, William A.; Whitt, Ward
2008
A note on the event horizon for a processor sharing queue. Zbl 1162.90395
Hampshire, Robert C.; Massey, William A.
2008
Fluid and diffusion limits for transient sojourn times of processor sharing queues with time varying rates. Zbl 1117.60083
Hampshire, Robert C.; Harchol-Balter, Mor; Massey, William A.
2006
A nonstationary offered-load model for packet networks. Zbl 1030.68650
Duffield, N. G.; Massey, W. A.; Whitt, W.
2001
Strong approximation for Markovian service networks. Zbl 0911.90167
Mandelbaum, Avi; Massey, William A.; Reiman, Martin I.
1998
Uniform acceleration expansions for Markov chains with time-varying rates. Zbl 0937.60066
Massey, William A.; Whitt, Ward
1998
Peak congestion in multi-server service systems with slowly varying arrival rates. Zbl 0878.90044
Massey, William A.; Whitt, Ward
1997
Server staffing to meet time-varying demand. Zbl 0880.90052
Jennings, Otis B.; Mandelbaum, Avishai; Massey, William A.; Whitt, Ward
1996
Stationary-process approximations for the nonstationary Erlang loss model. Zbl 0879.90099
Massey, William A.; Whitt, Ward
1996
Strong approximations for time-dependent queues. Zbl 0834.60096
Mandelbaum, Avi; Massey, William A.
1995
Sensitivity to the service-time distribution in the nonstationary Erlang loss model. Zbl 0865.60091
Davis, Jimmie L.; Massey, William A.; Whitt, Ward
1995
The spanning tree enumerating problem for digraphs. Zbl 0844.05053
Dean, Nathaniel; Kelmans, A. K.; Lih, Keh-Wei; Massey, William A.; Winkler, Peter
1995
An analysis of the modified offered-load approximation for the nonstationary Erlang loss model. Zbl 0812.60082
Massey, William A.; Whitt, Ward
1994
Unstable asymptotics for nonstationary queues. Zbl 0801.60087
Massey, William A.; Whitt, Ward
1994
Determining the exit time distribution for a closed cyclic network. Zbl 0789.60074
Baccelli, François; Massey, William A.; Wright, Paul E.
1994
Networks of infinite-server queues with nonstationary Poisson input. Zbl 0778.60068
Massey, William A.; Whitt, Ward
1993
The physics of the $$M_ t/G/\infty$$ queue. Zbl 0781.60086
Eick, Stephen G.; Massey, William A.; Whitt, Ward
1993
$$M_ t/G/\infty$$ queues with sinusoidal arrival rates. Zbl 0773.60086
Eick, Stephen G.; Massey, William A.; Whitt, Ward
1993
A probabilistic generalization of Taylor’s theorem. Zbl 0765.60032
Massey, William A.; Whitt, Ward
1993
Stochastic ordering for Markov processes on partially ordered spaces with applications to queueing networks. Zbl 0760.60088
Massey, William A.
1991
Acyclic fork-join queueing networks. Zbl 0675.90033
Baccelli, François; Massey, William A.; Towsley, Don
1989
A sample path analysis of the M/M/1 queue. Zbl 0683.60070
Baccelli, François; Massey, William A.
1989
Stochastic orderings for Markov processes on partially ordered spaces. Zbl 0622.60098
Massey, William A.
1987
Calculating exit times for series Jackson networks. Zbl 0626.60091
Massey, William A.
1987
A family of bounds for the transient behavior of a Jackson network. Zbl 0602.60084
Massey, William A.
1986
Asymptotic analysis of the time dependent M/M/1 queue. Zbl 0567.60089
Massey, William A.
1985
The non-ergodic Jackson network. Zbl 0562.60096
Goodman, Jonathan B.; Massey, William A.
1984
An operator-analytic approach to the Jackson network. Zbl 0539.60093
Massey, William A.
1984
Open networks of queues: Their algebraic structure and estimating their transient behavior. Zbl 0528.60093
Massey, William A.
1984
Calculation of steady-state probabilities for content of buffer with correlated inputs. Zbl 0389.94026
Massey, W. A.; Morrison, J. A.
1978
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#### Cited by 490 Authors
38 Whitt, Ward 19 Pender, Jamol 13 Liu, Yunan 11 Mandelbaum, Avi 11 Massey, William A. 9 Zeifman, Alexander Izrailevich 7 van Dijk, Nico M. 7 Yin, Gang George 6 Guo, Yongjiang 6 Pang, Guodong 5 Baccelli, François Louis 5 Boucherie, Richard J. 5 Di Crescenzo, Antonio 5 Mandjes, Michel Robertus Hendrikus 5 Momčilović, Petar 5 Ramanan, Kavita 5 Ross, Andrew M. 4 Hampshire, Robert C. 4 Ko, Young Myoung 4 Pekergin, Nihal 4 Rand, Richard H. 4 Satin, Ya. A. 4 Tezcan, Tolga 4 Wesson, Elizabeth N. 3 Atar, Rami 3 Bet, Gianmarco 3 Boxma, Onno Johan 3 Daw, Andrew 3 Gao, Xuefeng 3 Ingolfsson, Armann 3 Korolev, Viktor Yur’evich 3 Lebedev, Eugene O. 3 Lipshutz, David 3 Liu, Liming 3 Ma, Ni 3 Nazarov, Anatoly A. 3 Nguyen, Son Luu 3 Nobile, Amelia G. 3 Puhalskii, Anatolii A. 3 Shanthikumar, Jeyaveerasingam George 3 Templeton, James G. C. 3 Tran, Ky Quan 3 van Leeuwaarden, Johan S. H. 3 Weiss, Gideon 3 Willmot, Gordon E. 3 Worthington, Dave 3 Yin, George Gang 3 Zeltyn, Sergey 3 Zhang, Hanqin 3 Zwart, Bert P. 2 Abramov, Vyacheslav M. 2 Adan, Ivo J. B. F. 2 Adell, José Antonio 2 Ata, Baris 2 Bekker, Rebecca 2 Böhm, Walter 2 Borst, Sem C. 2 Bruneel, Herwig 2 Chao, Xiuli 2 Chen, Hong 2 Chernavskaya, E. A. 2 Daduna, Hans 2 Dai Pra, Paolo 2 Damodaran, Purushothaman 2 Dayar, Tugrul 2 De Bruin, A. M. 2 Delgado, Rosario 2 Foss, Sergey G. 2 Fralix, Brian H. 2 Gaujal, Bruno 2 Giorno, Virginia 2 Glynn, Peter W. 2 Goldberg, David Alan 2 Heidergott, Bernd F. 2 Hulett, Maria 2 Izady, Navid 2 Javier López, F. 2 Jennings, Otis B. 2 Jonckheere, Matthieu 2 Kang, Weining 2 Kelbert, Mark Ya. 2 Knessl, Charles 2 Krishna Kumar, Balasubramanian 2 Leahu, Haralambie 2 Lee, Chihoon 2 Leskelä, Lasse 2 Liu, Ran 2 Löpker, Andreas H. 2 Louis, Pierre-Yves 2 Margolius, Barbara H. 2 Mathijsen, Britt W. J. 2 Minelli, Ida Germana 2 Moiseev, Alexander 2 Motaei, Amir 2 Perros, Harry G. 2 Piunovskiĭ, Alekseĭ Borisovich 2 Rüschendorf, Ludger 2 Sanz, Gerardo 2 Satin, Yacov 2 Sen, Kanwar ...and 390 more Authors
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#### Cited in 88 Serials
69 Queueing Systems 25 European Journal of Operational Research 18 Probability in the Engineering and Informational Sciences 16 The Annals of Applied Probability 15 Operations Research Letters 11 Annals of Operations Research 9 Operations Research 9 Stochastic Processes and their Applications 8 Computers & Operations Research 8 Stochastic Models 7 Journal of Applied Probability 6 Statistics & Probability Letters 6 Journal of Mathematical Sciences (New York) 6 INFORMS Journal on Computing 6 Stochastic Systems 5 Advances in Applied Probability 5 Journal of Statistical Planning and Inference 5 Mathematics of Operations Research 5 Automation and Remote Control 5 Methodology and Computing in Applied Probability 5 Stochastics 4 Acta Mathematicae Applicatae Sinica. English Series 4 Discrete Event Dynamic Systems 4 Mathematical Methods of Operations Research 4 OR Spectrum 3 Journal of Mathematical Analysis and Applications 3 Journal of Statistical Physics 2 The Annals of Probability 2 Kybernetika 2 Theoretical Computer Science 2 Insurance Mathematics & Economics 2 International Journal of Production Research 2 Annales de l’Institut Henri Poincaré. Probabilités et Statistiques 2 Cybernetics and Systems Analysis 2 Applied Stochastic Models in Business and Industry 2 Scandinavian Actuarial Journal 1 Applicable Analysis 1 Mathematical Biosciences 1 Mathematical Notes 1 Problems of Information Transmission 1 Chaos, Solitons and Fractals 1 Theory of Probability and its Applications 1 Applied Mathematics and Computation 1 Automatica 1 Information Sciences 1 Journal of Combinatorial Theory. Series A 1 Journal of Computational and Applied Mathematics 1 Journal of Economic Theory 1 Journal of Soviet Mathematics 1 Nonlinear Analysis. Theory, Methods & Applications. Series A: Theory and Methods 1 Opsearch 1 Transactions of the American Mathematical Society 1 Stochastic Analysis and Applications 1 Acta Mathematica Hungarica 1 American Journal of Mathematical and Management Sciences 1 Statistical Science 1 Journal of Theoretical Probability 1 Applied Mathematics Letters 1 Mathematical and Computer Modelling 1 Machine Learning 1 Applied Mathematical Modelling 1 Communications in Statistics. Theory and Methods 1 SIAM Journal on Mathematical Analysis 1 SIAM Review 1 International Journal of Bifurcation and Chaos in Applied Sciences and Engineering 1 Lifetime Data Analysis 1 International Transactions in Operational Research 1 European Series in Applied and Industrial Mathematics (ESAIM): Probability and Statistics 1 Nonlinear Dynamics 1 Abstract and Applied Analysis 1 Journal of Combinatorial Optimization 1 Journal of Scheduling 1 Fractional Calculus & Applied Analysis 1 International Journal of Theoretical and Applied Finance 1 Macroeconomic Dynamics 1 International Journal of Applied Mathematics and Computer Science 1 RAIRO. Operations Research 1 International Game Theory Review 1 Brazilian Journal of Probability and Statistics 1 The ANZIAM Journal 1 Sādhanā 1 Comptes Rendus. Mathématique. Académie des Sciences, Paris 1 ASTIN Bulletin 1 Advances in Difference Equations 1 Journal of Industrial and Management Optimization 1 Frontiers of Mathematics in China 1 The Annals of Applied Statistics 1 Journal of Computational Dynamics
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#### Cited in 18 Fields
255 Probability theory and stochastic processes (60-XX) 229 Operations research, mathematical programming (90-XX) 48 Computer science (68-XX) 26 Statistics (62-XX) 14 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 14 Systems theory; control (93-XX) 10 Ordinary differential equations (34-XX) 9 Calculus of variations and optimal control; optimization (49-XX) 8 Numerical analysis (65-XX) 7 Partial differential equations (35-XX) 5 Biology and other natural sciences (92-XX) 4 Statistical mechanics, structure of matter (82-XX) 3 Combinatorics (05-XX) 2 Linear and multilinear algebra; matrix theory (15-XX) 2 Special functions (33-XX) 2 Approximations and expansions (41-XX) 2 Operator theory (47-XX) 1 Real functions (26-XX)
#### Wikidata Timeline
The data are displayed as stored in Wikidata under a Creative Commons CC0 License. Updates and corrections should be made in Wikidata.
| 2021-01-19T00:31:03 |
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https://par.nsf.gov/biblio/10174275
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Sensitivity of the ${}^{13}\mathrm{C}\left(\alpha ,n\right){}^{16}\mathrm{O}\phantom{\rule{4pt}{0ex}}S$ factor to the uncertainty in the level parameters of the near-threshold state
Authors:
; ; ; ; ;
Award ID(s):
Publication Date:
NSF-PAR ID:
10174275
Journal Name:
Physical Review C
Volume:
101
Issue:
4
ISSN:
2469-9985
| 2023-02-09T00:37:09 |
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https://indico.fnal.gov/event/19348/contributions/186573/
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Indico search will be reestablished in the next version upgrade of the software: https://getindico.io/roadmap/
# Neutrino 2020
June 22, 2020 to July 2, 2020
US/Central timezone
## Exploring the effect of Lorentz invariance violation with the currently running long-baseline experiments.
Not scheduled
10m
Poster
### Speaker
Mr RUDRA MAJHI (UNIVERSITY OF HYDERABAD)
### Description
Neutrinos can propagate very long distances without any deviation as they undergo only through weak interactions. This characteristic property can thus provide an ideal platform to investigate Planck suppressed physics, such as CPT violation, through their long distance propagation. CPT violation can be studied through Lorentz invariance violation (LIV) in the long-baseline neutrino oscillation experiments. Considering four-dimensional Lorentz violating parameters, we obtain the sensitivity limits on the LIV parameters from NO$\nu$A and T2K experiments. The sensitivity limits on LIV parameters obtained from T2K are much weaker than that of NO$\nu$A and the synergy of T2K and NO$\nu$A can improve these sensitivities. Also, we show their effects on mass hierarchy and CP violation sensitivities for NO$\nu$A experiment. The mass hierarchy and CPV sensitivities are either enhanced or deteriorated significantly, as they crucially depend on the CP-violating phases of LIV parameters.
### Mini-abstract
Sensitivity Limits on LIV parameters and their effects are studied for NOvA and T2K experiments.
Experiment/Collaboration NOvA
### Primary author
Mr RUDRA MAJHI (UNIVERSITY OF HYDERABAD)
### Co-authors
Prof. Rukmani Mohanta (University of Hyderabad) Dr Soumya C. (Institue of Physics, Bhubaneswar, India)
### Presentation Materials
LIV-NEUTRINO-2020-ID-309.mp4 LIV-Neutrino-2020.pdf
| 2021-11-27T18:13:40 |
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|
https://zbmath.org/authors/?q=ai%3Atretter.christiane
|
# zbMATH — the first resource for mathematics
## Tretter, Christiane
Compute Distance To:
Author ID: tretter.christiane Published as: Tretter, C.; Tretter, Ch.; Tretter, Chr.; Tretter, Christiane Homepage: http://www.philnat.unibe.ch/a_dept_math/a_inst_math/content/ueber_uns/personen/p... External Links: MGP · Wikidata · dblp
Documents Indexed: 85 Publications since 1992, including 8 Books Reviewing Activity: 68 Reviews
all top 5
#### Co-Authors
18 single-authored 22 Langer, Heinz 8 Langer, Matthias 7 Marletta, Marco 6 Mennicken, Reinhard 5 Markus, Alexander S. 5 Wagenhofer, Markus 4 Bögli, Sabine 4 Brown, B. Malcolm 4 Ibrogimov, Orif O. 4 Pivovarchik, Vyacheslav N. 4 Shkalikov, Andreĭ Andreevich 3 Adamyan, Vadym Movsesovych 3 Siegl, Petr 2 Cuenin, Jean-Claude 2 Denk, Robert 2 Gohberg, Israel 2 Kraus, Margarita 2 Matsaev, Vladimir Igorevich 2 Möller, Manfred 2 Naboko, Serguei N. 2 Najman, Branko 2 Pivovarchik, Vyacheslav M. 2 Schmid, Harald 2 Winklmeier, Monika 1 Albeverio, Sergio A. 1 Arlins’kyĭ, Yuriĭ Moĭseĭovych 1 Engström, Christian 1 Freitas, Pedro 1 Günther, Uwe 1 Jacob, Birgit 1 Kopachevsky, Nikolay Dmitrievich 1 Koppen, Mario 1 Laptev, Ari 1 Li, Chi-Kwong 1 Martynuk, Olga 1 Motovilov, Aleksandr Konstantinovich 1 Pashkova, Yuliya S. 1 Radl, Agnes 1 Rasulov, Tulkin Khusenovich 1 Rodman, Leiba X. 1 Rozhenko, Natalia A. 1 Sakhnovich, Alexander L. 1 Trunk, Carsten 1 Vogt, Hendrik 1 Wyss, Christian
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#### Serials
5 Integral Equations and Operator Theory 5 Journal of Differential Equations 5 Journal of Functional Analysis 4 Journal of Mathematical Analysis and Applications 3 Mathematische Nachrichten 3 Complex Analysis and Operator Theory 2 Linear and Multilinear Algebra 2 Zeitschrift für Angewandte Mathematik und Mechanik (ZAMM) 2 Indiana University Mathematics Journal 2 Journal of Operator Theory 2 Journal of Physics A: Mathematical and General 2 Linear Algebra and its Applications 2 Proceedings of the Royal Society of Edinburgh. Section A. Mathematics 2 Czechoslovak Journal of Physics 2 Operator Theory: Advances and Applications 2 Mathematik Kompakt 1 Applicable Analysis 1 Communications in Mathematical Physics 1 Journal of Mathematical Physics 1 Mathematical Methods in the Applied Sciences 1 Rocky Mountain Journal of Mathematics 1 Reviews in Mathematical Physics 1 Acta Scientiarum Mathematicarum 1 Advances in Mathematics 1 Duke Mathematical Journal 1 Journal of Computational and Applied Mathematics 1 Journal of the London Mathematical Society. Second Series 1 Mathematische Zeitschrift 1 Proceedings of the American Mathematical Society 1 Proceedings of the Edinburgh Mathematical Society. Series II 1 Transactions of the American Mathematical Society 1 Asymptotic Analysis 1 SIAM Journal on Matrix Analysis and Applications 1 Differential Geometry and its Applications 1 Communications in Partial Differential Equations 1 SIAM Journal on Applied Mathematics 1 SIAM Journal on Mathematical Analysis 1 Journal of Difference Equations and Applications 1 Methods of Functional Analysis and Topology 1 ZAMM. Zeitschrift für Angewandte Mathematik und Mechanik 1 Proceedings of the Royal Society of London. Series A. Mathematical, Physical and Engineering Sciences 1 LMS Journal of Computation and Mathematics 1 Annales Henri Poincaré 1 Journal of Evolution Equations 1 Operators and Matrices 1 Journal of Pseudo-Differential Operators and Applications
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#### Fields
59 Operator theory (47-XX) 34 Ordinary differential equations (34-XX) 19 Partial differential equations (35-XX) 15 Fluid mechanics (76-XX) 13 Quantum theory (81-XX) 6 Linear and multilinear algebra; matrix theory (15-XX) 5 Numerical analysis (65-XX) 4 Functional analysis (46-XX) 4 Calculus of variations and optimal control; optimization (49-XX) 3 General and overarching topics; collections (00-XX) 3 Difference and functional equations (39-XX) 3 Mechanics of particles and systems (70-XX) 3 Mechanics of deformable solids (74-XX) 2 Real functions (26-XX) 2 Integral equations (45-XX) 2 Global analysis, analysis on manifolds (58-XX) 2 Mathematics education (97-XX) 1 History and biography (01-XX) 1 Combinatorics (05-XX) 1 Functions of a complex variable (30-XX) 1 Approximations and expansions (41-XX) 1 Algebraic topology (55-XX) 1 Optics, electromagnetic theory (78-XX) 1 Statistical mechanics, structure of matter (82-XX)
#### Citations contained in zbMATH Open
69 Publications have been cited 627 times in 367 Documents Cited by Year
Spectral theory of block operator matrices and applications. Zbl 1173.47003
Tretter, Christiane
2008
A Krein space approach to $$PT$$ symmetry. Zbl 1162.81375
Langer, Heinz; Tretter, Christiane
2004
Boundary eigenvalue problems for differential equations $$N\eta=\lambda P\eta$$ with $$\lambda$$-polynomial boundary conditions. Zbl 0984.34010
Tretter, Christiane
2001
A new concept for block operator matrices: The quadratic numerical range. Zbl 0998.15035
Langer, H.; Markus, A.; Matsaev, V.; Tretter, C.
2001
Spectral decomposition of some nonselfadjoint block operator matrices. Zbl 0996.47006
Langer, Heinz; Tretter, Christiane
1998
Eigenvalue estimates for non-selfadjoint Dirac operators on the real line. Zbl 1287.81050
Cuenin, Jean-Claude; Laptev, Ari; Tretter, Christiane
2014
Spectral inclusion for unbounded block operator matrices. Zbl 1179.47005
Tretter, Christiane
2009
Spectral theory of the Klein-Gordon equation in Pontryagin spaces. Zbl 1114.47038
Langer, Heinz; Najman, Branko; Tretter, Christiane
2006
Singular Dirac systems and Sturm-Liouville problems nonlinear in the spectral parameter. Zbl 1012.34082
Schmid, Harald; Tretter, Christiane
2002
Spectral theory of the Klein-Gordon equation in Krein spaces. Zbl 1152.81020
Langer, Heinz; Najman, Branko; Tretter, Christiane
2008
Existence and uniqueness of contractive solutions of some Riccati equations. Zbl 0982.47019
2001
Diagonalization of certain block operator matrices and applications to Dirac operators. Zbl 0976.47014
Langer, Heinz; Tretter, Christiane
2001
Spectral analysis for linear pencils $$N-\lambda P$$ of ordinary differential operators. Zbl 0862.34058
Shkalikov, Andrey A.; Tretter, Christiane
1996
Self-adjoint block operator matrices with non-separated diagonal entries and their Schur complements. Zbl 1060.47004
Langer, H.; Markus, A.; Matsaev, V.; Tretter, C.
2003
Linear operator pencils $$A-\lambda B$$ with discrete spectrum. Zbl 0977.47012
Tretter, Christiane
2000
On $$\lambda$$-nonlinear boundary eigenvalue problems. Zbl 0785.34054
Tretter, Christiane
1993
Dirichlet-Neumann inverse spectral problem for a star graph of Stieltjes strings. Zbl 1286.34025
Pivovarchik, Vyacheslav; Rozhenko, Natalia; Tretter, Christiane
2013
Spectral problems for systems of differential equations $$y^{\prime} + A_0 y = \lambda A_1 y$$ with $$\lambda$$-polynomial boundary conditions. Zbl 0959.34067
Tretter, Christiane
2000
Kamke problems. Properties of the eigenfunctions. Zbl 0813.34071
Shalikov, Andrey A.; Tretter, Christiane
1994
Rational eigenvalue problems and applications to photonic crystals. Zbl 1351.65084
Engström, Christian; Langer, Heinz; Tretter, Christiane
2017
Direct and inverse spectral problem for a system of differential equations depending rationally on the spectral parameter. Zbl 1020.34024
Mennicken, R.; Sakhnovich, A. L.; Tretter, C.
2001
Variational principles and eigenvalue estimates for unbounded block operator matrices and applications. Zbl 1066.49030
Kraus, Margarita; Langer, Matthias; Tretter, Christiane
2004
The block numerical range of an $$n\times n$$ block operator matrix. Zbl 1051.47003
Tretter, Christiane; Wagenhofer, Markus
2003
Variational principles for eigenvalues of block operator matrices. Zbl 1048.47011
Langer, Heinz; Langer, Matthias; Tretter, Christiane
2002
Location and multiplicities of eigenvalues for a star graph of Stieltjes strings. Zbl 1328.39033
Pivovarchik, Vyacheslav; Tretter, Christiane
2015
On a class of non-self-adjoint quadric matrix operator pencils arising in elasticity theory. Zbl 1019.47017
2002
Essential spectrum of a system of singular differential operators and the asymptotic Hain-Lüst operator. Zbl 1044.47004
Mennicken, Reinhard; Naboko, Serguei; Tretter, Christiane
2002
Nonselfadjoint spectral problems for linear pencils $$N- \lambda P$$ of ordinary differential operators with $$\lambda$$-linear boundary conditions: Completeness results. Zbl 0862.34057
Tretter, Christiane
1996
Non-symmetric perturbations of self-adjoint operators. Zbl 1341.47017
Cuenin, Jean-Claude; Tretter, Christiane
2016
Dichotomous Hamiltonians with unbounded entries and solutions of Riccati equations. Zbl 1320.47012
Tretter, Christiane; Wyss, Christian
2014
Essential spectra of coupled systems of differential equations and applications in hydrodynamics. Zbl 1129.47061
Marletta, Marco; Tretter, Christiane
2007
Bounds on the spectrum and reducing subspaces of a $$J$$-self-adjoint operator. Zbl 1236.47032
Albeverio, Sergio; Motovilov, Alexander K.; Tretter, Christiane
2010
Approximations of spectra of Schrödinger operators with complex potentials on $$\mathbb{R}^d$$. Zbl 1384.35016
Bögli, Sabine; Siegl, Petr; Tretter, Christiane
2017
Spectrum of definite type of self-adjoint operators in Krein spaces. Zbl 1079.47040
Langer, Heinz; Langer, Matthias; Markus, Alexander; Tretter, Christiane
2005
Spectral issues for block operator matrices. Zbl 1056.47500
Tretter, Christiane
2000
A selfadjoint linear pencil $$Q-\lambda P$$ of ordinary differential operators. Zbl 0927.47008
Langer, Heinz; Mennicken, Reinhard; Tretter, Christiane
1996
Inverse problem for a damped Stieltjes string from parts of spectra. Zbl 1330.39021
Martynuk, Olga; Pivovarchik, Vyacheslav; Tretter, Christiane
2015
Pencils of differential operators containing the eigenvalue parameter in the boundary conditions. Zbl 1055.34021
Marletta, Marco; Shkalikov, Andrei; Tretter, Christiane
2003
Corners of numerical ranges. Zbl 0990.47007
Langer, Heinz; Markus, Alexander; Tretter, Christiane
2001
On fundamental systems for differential equations of Kamke type. Zbl 0827.34004
Tretter, Christiane
1995
The damped wave equation with unbounded damping. Zbl 1392.35188
Freitas, Pedro; Siegl, Petr; Tretter, Christiane
2018
Eigenvalue enclosures and exclosures for non-self-adjoint problems in hydrodynamics. Zbl 1301.76083
Brown, B. Malcolm; Langer, Matthias; Marletta, Marco; Tretter, Christiane; Wagenhofer, Markus
2010
A linearization for a class of $$\lambda$$-nonlinear boundary eigenvalue problems. Zbl 0959.34066
Tretter, Christiane
2000
Spectral properties of the Orr-Sommerfeld problem. Zbl 0897.34070
Langer, Heinz; Tretter, Christiane
1997
Dirac-Krein systems on star graphs. Zbl 1360.81155
Adamyan, V.; Langer, H.; Tretter, C.; Winklmeier, M.
2016
Essential spectrum of systems of singular differential equations. Zbl 1324.47029
Ibrogimov, Orif O.; Langer, Heinz; Langer, Matthias; Tretter, Christiane
2013
Corrigendum to: A Krein space approach to $$PT$$ symmetry. Zbl 1163.81309
Langer, Heinz; Tretter, Christiane
2006
Eigenvalue bounds for the singular Sturm-Liouville problem with a complex potential. Zbl 1058.34113
Brown, B. M.; Langer, M.; Marletta, M.; Tretter, C.; Wagenhofer, M.
2003
On buckling problems. Zbl 0974.34079
Tretter, C.
2000
The essential numerical range for unbounded linear operators. Zbl 07190456
Bögli, Sabine; Marletta, Marco; Tretter, Christiane
2020
On the spectrum of an operator in truncated Fock space. Zbl 1402.81151
Ibrogimov, Orif O.; Tretter, Christiane
2018
Analysis of the essential spectrum of singular matrix differential operators. Zbl 1328.47008
Ibrogimov, O. O.; Siegl, P.; Tretter, C.
2016
Guaranteed resonance enclosures and exclosures for atoms and molecules. Zbl 1371.81347
Bögli, Sabine; Brown, B. Malcolm; Marletta, Marco; Tretter, Christiane; Wagenhofer, Markus
2014
On the spectrum of the magnetohydrodynamic mean-field $$\alpha^2$$-dynamo operator. Zbl 1218.47008
Günther, Uwe; Langer, Heinz; Tretter, Christiane
2010
The Virozub-Matsaev condition and spectrum of definite type for self-adjoint operator functions. Zbl 1177.47019
Langer, Heinz; Langer, Matthias; Markus, Alexander; Tretter, Christiane
2008
Variational principles for eigenvalues of the Klein-Gordon equation. Zbl 1112.78008
Langer, Matthias; Tretter, Christiane
2006
Asymptotic separation of the spectrum of quadratic operator pencils associated with damped dynamical systems. Zbl 1068.47018
Pivovarchik, Vjacheslav; Tretter, Christiane
2003
Everything is possible for the domain intersection dom $$T \cap$$ dom $$T^\ast$$. Zbl 07258214
Arlinskiĭ, Yury; Tretter, Christiane
2020
Systems with strong damping and their spectra. Zbl 06986309
Jacob, Birgit; Tretter, Christiane; Trunk, Carsten; Vogt, Hendrik
2018
Spectral inclusion for unbounded diagonally dominant $$n\times n$$ operator matrices. Zbl 06866711
Rasulov, Tulkin H.; Tretter, Christiane
2018
Essential spectrum of elliptic systems of pseudo-differential operators on $$L^2(\mathbb {R}^N) \oplus L^2(\mathbb {R}^N)$$. Zbl 06818249
Ibrogimov, Orif O.; Tretter, Christiane
2017
Spectral bounds and basis results for non-self-adjoint pencils, with an application to Hagen-Poiseuille flow. Zbl 1262.47006
Marletta, Marco; Tretter, Christiane
2013
Simplicity of extremal eigenvalues of the Klein-Gordon equation. Zbl 1228.81165
Koppen, Mario; Tretter, Christiane; Winklmeier, Monika
2011
The spectrum of the multiplication operator associated with a family of operators in a Banach space. Zbl 1108.47006
Denk, R.; Möller, M.; Tretter, C.
2006
Eigenvalue accumulation for Dirac operators with spherically symmetric potential. Zbl 1064.81040
Schmid, Harald; Tretter, Christiane
2004
A new method for eigenvalue estimates for Dirac operators on certain manifolds with $$S^{k}$$-symmetry. Zbl 1030.58023
Kraus, Margarita; Tretter, Christiane
2003
The spectrum of a parametrized partial differential operator occurring in hydrodynamics. Zbl 1017.47035
Denk, R.; Möller, M.; Tretter, C.
2002
Lyapunov stability of a perturbed multiplication operator. Zbl 0921.47028
Naboko, S. N.; Tretter, C.
1998
Spectral properties of a compactly perturbed linear span of projections. Zbl 0865.47009
Langer, H.; Pivovarchik, V.; Tretter, C.
1996
The essential numerical range for unbounded linear operators. Zbl 07190456
Bögli, Sabine; Marletta, Marco; Tretter, Christiane
2020
Everything is possible for the domain intersection dom $$T \cap$$ dom $$T^\ast$$. Zbl 07258214
Arlinskiĭ, Yury; Tretter, Christiane
2020
The damped wave equation with unbounded damping. Zbl 1392.35188
Freitas, Pedro; Siegl, Petr; Tretter, Christiane
2018
On the spectrum of an operator in truncated Fock space. Zbl 1402.81151
Ibrogimov, Orif O.; Tretter, Christiane
2018
Systems with strong damping and their spectra. Zbl 06986309
Jacob, Birgit; Tretter, Christiane; Trunk, Carsten; Vogt, Hendrik
2018
Spectral inclusion for unbounded diagonally dominant $$n\times n$$ operator matrices. Zbl 06866711
Rasulov, Tulkin H.; Tretter, Christiane
2018
Rational eigenvalue problems and applications to photonic crystals. Zbl 1351.65084
Engström, Christian; Langer, Heinz; Tretter, Christiane
2017
Approximations of spectra of Schrödinger operators with complex potentials on $$\mathbb{R}^d$$. Zbl 1384.35016
Bögli, Sabine; Siegl, Petr; Tretter, Christiane
2017
Essential spectrum of elliptic systems of pseudo-differential operators on $$L^2(\mathbb {R}^N) \oplus L^2(\mathbb {R}^N)$$. Zbl 06818249
Ibrogimov, Orif O.; Tretter, Christiane
2017
Non-symmetric perturbations of self-adjoint operators. Zbl 1341.47017
Cuenin, Jean-Claude; Tretter, Christiane
2016
Dirac-Krein systems on star graphs. Zbl 1360.81155
Adamyan, V.; Langer, H.; Tretter, C.; Winklmeier, M.
2016
Analysis of the essential spectrum of singular matrix differential operators. Zbl 1328.47008
Ibrogimov, O. O.; Siegl, P.; Tretter, C.
2016
Location and multiplicities of eigenvalues for a star graph of Stieltjes strings. Zbl 1328.39033
Pivovarchik, Vyacheslav; Tretter, Christiane
2015
Inverse problem for a damped Stieltjes string from parts of spectra. Zbl 1330.39021
Martynuk, Olga; Pivovarchik, Vyacheslav; Tretter, Christiane
2015
Eigenvalue estimates for non-selfadjoint Dirac operators on the real line. Zbl 1287.81050
Cuenin, Jean-Claude; Laptev, Ari; Tretter, Christiane
2014
Dichotomous Hamiltonians with unbounded entries and solutions of Riccati equations. Zbl 1320.47012
Tretter, Christiane; Wyss, Christian
2014
Guaranteed resonance enclosures and exclosures for atoms and molecules. Zbl 1371.81347
Bögli, Sabine; Brown, B. Malcolm; Marletta, Marco; Tretter, Christiane; Wagenhofer, Markus
2014
Dirichlet-Neumann inverse spectral problem for a star graph of Stieltjes strings. Zbl 1286.34025
Pivovarchik, Vyacheslav; Rozhenko, Natalia; Tretter, Christiane
2013
Essential spectrum of systems of singular differential equations. Zbl 1324.47029
Ibrogimov, Orif O.; Langer, Heinz; Langer, Matthias; Tretter, Christiane
2013
Spectral bounds and basis results for non-self-adjoint pencils, with an application to Hagen-Poiseuille flow. Zbl 1262.47006
Marletta, Marco; Tretter, Christiane
2013
Simplicity of extremal eigenvalues of the Klein-Gordon equation. Zbl 1228.81165
Koppen, Mario; Tretter, Christiane; Winklmeier, Monika
2011
Bounds on the spectrum and reducing subspaces of a $$J$$-self-adjoint operator. Zbl 1236.47032
Albeverio, Sergio; Motovilov, Alexander K.; Tretter, Christiane
2010
Eigenvalue enclosures and exclosures for non-self-adjoint problems in hydrodynamics. Zbl 1301.76083
Brown, B. Malcolm; Langer, Matthias; Marletta, Marco; Tretter, Christiane; Wagenhofer, Markus
2010
On the spectrum of the magnetohydrodynamic mean-field $$\alpha^2$$-dynamo operator. Zbl 1218.47008
Günther, Uwe; Langer, Heinz; Tretter, Christiane
2010
Spectral inclusion for unbounded block operator matrices. Zbl 1179.47005
Tretter, Christiane
2009
Spectral theory of block operator matrices and applications. Zbl 1173.47003
Tretter, Christiane
2008
Spectral theory of the Klein-Gordon equation in Krein spaces. Zbl 1152.81020
Langer, Heinz; Najman, Branko; Tretter, Christiane
2008
The Virozub-Matsaev condition and spectrum of definite type for self-adjoint operator functions. Zbl 1177.47019
Langer, Heinz; Langer, Matthias; Markus, Alexander; Tretter, Christiane
2008
Essential spectra of coupled systems of differential equations and applications in hydrodynamics. Zbl 1129.47061
Marletta, Marco; Tretter, Christiane
2007
Spectral theory of the Klein-Gordon equation in Pontryagin spaces. Zbl 1114.47038
Langer, Heinz; Najman, Branko; Tretter, Christiane
2006
Corrigendum to: A Krein space approach to $$PT$$ symmetry. Zbl 1163.81309
Langer, Heinz; Tretter, Christiane
2006
Variational principles for eigenvalues of the Klein-Gordon equation. Zbl 1112.78008
Langer, Matthias; Tretter, Christiane
2006
The spectrum of the multiplication operator associated with a family of operators in a Banach space. Zbl 1108.47006
Denk, R.; Möller, M.; Tretter, C.
2006
Spectrum of definite type of self-adjoint operators in Krein spaces. Zbl 1079.47040
Langer, Heinz; Langer, Matthias; Markus, Alexander; Tretter, Christiane
2005
A Krein space approach to $$PT$$ symmetry. Zbl 1162.81375
Langer, Heinz; Tretter, Christiane
2004
Variational principles and eigenvalue estimates for unbounded block operator matrices and applications. Zbl 1066.49030
Kraus, Margarita; Langer, Matthias; Tretter, Christiane
2004
Eigenvalue accumulation for Dirac operators with spherically symmetric potential. Zbl 1064.81040
Schmid, Harald; Tretter, Christiane
2004
Self-adjoint block operator matrices with non-separated diagonal entries and their Schur complements. Zbl 1060.47004
Langer, H.; Markus, A.; Matsaev, V.; Tretter, C.
2003
The block numerical range of an $$n\times n$$ block operator matrix. Zbl 1051.47003
Tretter, Christiane; Wagenhofer, Markus
2003
Pencils of differential operators containing the eigenvalue parameter in the boundary conditions. Zbl 1055.34021
Marletta, Marco; Shkalikov, Andrei; Tretter, Christiane
2003
Eigenvalue bounds for the singular Sturm-Liouville problem with a complex potential. Zbl 1058.34113
Brown, B. M.; Langer, M.; Marletta, M.; Tretter, C.; Wagenhofer, M.
2003
Asymptotic separation of the spectrum of quadratic operator pencils associated with damped dynamical systems. Zbl 1068.47018
Pivovarchik, Vjacheslav; Tretter, Christiane
2003
A new method for eigenvalue estimates for Dirac operators on certain manifolds with $$S^{k}$$-symmetry. Zbl 1030.58023
Kraus, Margarita; Tretter, Christiane
2003
Singular Dirac systems and Sturm-Liouville problems nonlinear in the spectral parameter. Zbl 1012.34082
Schmid, Harald; Tretter, Christiane
2002
Variational principles for eigenvalues of block operator matrices. Zbl 1048.47011
Langer, Heinz; Langer, Matthias; Tretter, Christiane
2002
On a class of non-self-adjoint quadric matrix operator pencils arising in elasticity theory. Zbl 1019.47017
2002
Essential spectrum of a system of singular differential operators and the asymptotic Hain-Lüst operator. Zbl 1044.47004
Mennicken, Reinhard; Naboko, Serguei; Tretter, Christiane
2002
The spectrum of a parametrized partial differential operator occurring in hydrodynamics. Zbl 1017.47035
Denk, R.; Möller, M.; Tretter, C.
2002
Boundary eigenvalue problems for differential equations $$N\eta=\lambda P\eta$$ with $$\lambda$$-polynomial boundary conditions. Zbl 0984.34010
Tretter, Christiane
2001
A new concept for block operator matrices: The quadratic numerical range. Zbl 0998.15035
Langer, H.; Markus, A.; Matsaev, V.; Tretter, C.
2001
Existence and uniqueness of contractive solutions of some Riccati equations. Zbl 0982.47019
2001
Diagonalization of certain block operator matrices and applications to Dirac operators. Zbl 0976.47014
Langer, Heinz; Tretter, Christiane
2001
Direct and inverse spectral problem for a system of differential equations depending rationally on the spectral parameter. Zbl 1020.34024
Mennicken, R.; Sakhnovich, A. L.; Tretter, C.
2001
Corners of numerical ranges. Zbl 0990.47007
Langer, Heinz; Markus, Alexander; Tretter, Christiane
2001
Linear operator pencils $$A-\lambda B$$ with discrete spectrum. Zbl 0977.47012
Tretter, Christiane
2000
Spectral problems for systems of differential equations $$y^{\prime} + A_0 y = \lambda A_1 y$$ with $$\lambda$$-polynomial boundary conditions. Zbl 0959.34067
Tretter, Christiane
2000
Spectral issues for block operator matrices. Zbl 1056.47500
Tretter, Christiane
2000
A linearization for a class of $$\lambda$$-nonlinear boundary eigenvalue problems. Zbl 0959.34066
Tretter, Christiane
2000
On buckling problems. Zbl 0974.34079
Tretter, C.
2000
Spectral decomposition of some nonselfadjoint block operator matrices. Zbl 0996.47006
Langer, Heinz; Tretter, Christiane
1998
Lyapunov stability of a perturbed multiplication operator. Zbl 0921.47028
Naboko, S. N.; Tretter, C.
1998
Spectral properties of the Orr-Sommerfeld problem. Zbl 0897.34070
Langer, Heinz; Tretter, Christiane
1997
Spectral analysis for linear pencils $$N-\lambda P$$ of ordinary differential operators. Zbl 0862.34058
Shkalikov, Andrey A.; Tretter, Christiane
1996
Nonselfadjoint spectral problems for linear pencils $$N- \lambda P$$ of ordinary differential operators with $$\lambda$$-linear boundary conditions: Completeness results. Zbl 0862.34057
Tretter, Christiane
1996
A selfadjoint linear pencil $$Q-\lambda P$$ of ordinary differential operators. Zbl 0927.47008
Langer, Heinz; Mennicken, Reinhard; Tretter, Christiane
1996
Spectral properties of a compactly perturbed linear span of projections. Zbl 0865.47009
Langer, H.; Pivovarchik, V.; Tretter, C.
1996
On fundamental systems for differential equations of Kamke type. Zbl 0827.34004
Tretter, Christiane
1995
Kamke problems. Properties of the eigenfunctions. Zbl 0813.34071
Shalikov, Andrey A.; Tretter, Christiane
1994
On $$\lambda$$-nonlinear boundary eigenvalue problems. Zbl 0785.34054
Tretter, Christiane
1993
all top 5
#### Cited by 437 Authors
39 Tretter, Christiane 15 Jeribi, Aref 14 Langer, Heinz 12 Chen, Alatancang 12 Wang, Junmin 10 Trunk, Carsten 9 Marletta, Marco 9 Siegl, Petr 9 Znojil, Miloslav 8 Ibrogimov, Orif O. 8 Langer, Matthias 8 Motovilov, Aleksandr Konstantinovich 8 Sakhnovich, Alexander L. 7 Ammar, Aymen 6 Albeverio, Sergio A. 6 Behrndt, Jussi 6 Cuenin, Jean-Claude 6 Engström, Christian 6 Guo, Bao-Zhu 6 Krejčiřík, David 6 Rasulov, Tulkin Khusenovich 6 Shkalikov, Andreĭ Andreevich 6 Strauss, Michael A. 5 Markus, Alexander S. 5 Ozkan, Ahmet Sinan 5 Pivovarchik, Vyacheslav N. 5 Wyss, Christian 4 Azizov, Tomas Ya. 4 Bögli, Sabine 4 Boulton, Lyonell S. 4 Dijksma, Aad 4 Huang, Junjie 4 Krichen, Bilel 4 Makarov, Konstantin A. 4 Möller, Manfred 4 Philipp, Friedrich 4 Torshage, Axel 4 Winklmeier, Monika 4 Wu, Deyu 4 Xu, Gen-Qi 4 Yurko, Vjacheslav Anatoljevich 3 Aliyev, Ziyatkhan S. 3 Brown, B. Malcolm 3 Chen, Shaozhu 3 Cvetković-Ilić, Dragana S. 3 Fritzsche, Bernd 3 Gérard, Christian 3 Gesztesy, Fritz 3 Gil’, Michael Iosif 3 Grubišić, Luka 3 Günther, Uwe 3 Häfner, Dietrich 3 Keskin, Baki 3 Kirstein, Bernd 3 Kostrykin, Vadim V. 3 Laptev, Ari 3 Matsaev, Vladimir Igorevich 3 Moalla, Nedra 3 Muhammad, Ahmed 3 Psarrakos, Panayiotis J. 3 Qi, Jiangang 3 Ran, André C. M. 3 Saadaoui, Bilel 3 Štampach, František 3 Veselić, Krešimir 3 Yung, Siu Pang 3 Zinsou, Bertin 2 Adamyan, Vadym Movsesovych 2 Annaby, Mahmoud H. 2 Arlins’kyĭ, Yuriĭ Moĭseĭovych 2 Aydemir, Kadriye 2 Bartels, Casey 2 Bebiano, Natália Isabel Quadros 2 Borisov, Denis Ivanovich 2 Boussaid, Nabile 2 Chanane, Bilal 2 Chentouf, Boumediène 2 Currie, Sonja 2 da Providência Santarém e Costa, João 2 Davies, Edward Brian 2 Deng, Lianwang 2 Dilmurodov, Elyor B. 2 Engel, Klaus-Jochen 2 Fanelli, Luca 2 Freiling, Gerhard 2 Freitas, Pedro 2 Frommer, Andreas 2 Gardas, Bartłomiej 2 Georgescu, Vladimir 2 Giga, Yoshikazu 2 Giribet, Juan Ignacio 2 Gridneva, Irina V. 2 Güldü, Yalçın 2 Guo, Yongxia 2 Hai, Guojun 2 Han, Zhongjie 2 Hansmann, Marcel 2 Ilchmann, Achim 2 Jakubský, Vít 2 Jin, Guohai ...and 337 more Authors
all top 5
#### Cited in 128 Serials
38 Integral Equations and Operator Theory 22 Journal of Mathematical Analysis and Applications 19 Journal of Functional Analysis 16 Linear Algebra and its Applications 14 Journal of Mathematical Physics 14 Journal of Differential Equations 11 Mathematische Nachrichten 11 Complex Analysis and Operator Theory 10 Annales Henri Poincaré 8 Mathematical Methods in the Applied Sciences 8 Mathematical Notes 7 Journal of Spectral Theory 5 Proceedings of the American Mathematical Society 4 Journal of Computational and Applied Mathematics 3 Applicable Analysis 3 Communications in Mathematical Physics 3 International Journal of Theoretical Physics 3 Linear and Multilinear Algebra 3 Rocky Mountain Journal of Mathematics 3 Theoretical and Mathematical Physics 3 Advances in Mathematics 3 Applied Mathematics and Computation 3 Results in Mathematics 3 Transactions of the American Mathematical Society 3 Systems & Control Letters 3 Turkish Journal of Mathematics 3 Acta Mathematica Sinica. English Series 3 Differential Equations 3 Mediterranean Journal of Mathematics 3 Boundary Value Problems 3 Operators and Matrices 3 Analysis and Mathematical Physics 2 Journal of Statistical Physics 2 Letters in Mathematical Physics 2 Ukrainian Mathematical Journal 2 ZAMP. Zeitschrift für angewandte Mathematik und Physik 2 Reviews in Mathematical Physics 2 Numerische Mathematik 2 Transactions of the Moscow Mathematical Society 2 Constructive Approximation 2 Numerical Algorithms 2 SIAM Journal on Applied Mathematics 2 SIAM Journal on Mathematical Analysis 2 SIAM Review 2 Applied Mathematics. Series B (English Edition) 2 Journal of Mathematical Sciences (New York) 2 Opuscula Mathematica 2 European Series in Applied and Industrial Mathematics (ESAIM): Control, Optimization and Calculus of Variations 2 Abstract and Applied Analysis 2 Mathematical Physics, Analysis and Geometry 2 Positivity 2 LMS Journal of Computation and Mathematics 2 Czechoslovak Journal of Physics 2 Journal of Evolution Equations 2 Central European Journal of Mathematics 2 Journal of Pseudo-Differential Operators and Applications 2 Journal of Applied Analysis and Computation 1 International Journal of Modern Physics A 1 Archive for Rational Mechanics and Analysis 1 Computers & Mathematics with Applications 1 International Journal of Control 1 Israel Journal of Mathematics 1 Journal d’Analyse Mathématique 1 Journal of Engineering Mathematics 1 Journal of the Franklin Institute 1 Arkiv för Matematik 1 Fortschritte der Physik 1 Annali di Matematica Pura ed Applicata. Serie Quarta 1 The Annals of Statistics 1 BIT 1 Functional Analysis and its Applications 1 International Journal of Mathematics and Mathematical Sciences 1 Journal of Optimization Theory and Applications 1 Mathematische Annalen 1 Mathematische Zeitschrift 1 Monatshefte für Mathematik 1 Nonlinear Analysis. Theory, Methods & Applications. Series A: Theory and Methods 1 Numerical Functional Analysis and Optimization 1 SIAM Journal on Control and Optimization 1 Siberian Mathematical Journal 1 Studies in Applied Mathematics 1 Bulletin of the Korean Mathematical Society 1 Chinese Annals of Mathematics. Series B 1 Acta Mathematica Hungarica 1 Bulletin of the Iranian Mathematical Society 1 MCSS. Mathematics of Control, Signals, and Systems 1 Journal of Scientific Computing 1 Differential Geometry and its Applications 1 Applications of Mathematics 1 International Journal of Computer Mathematics 1 Journal de Mathématiques Pures et Appliquées. Neuvième Série 1 Proceedings of the Royal Society of Edinburgh. Section A. Mathematics 1 Indagationes Mathematicae. New Series 1 Journal of Inverse and Ill-Posed Problems 1 ETNA. Electronic Transactions on Numerical Analysis 1 NoDEA. Nonlinear Differential Equations and Applications 1 Journal of Difference Equations and Applications 1 Boletín de la Sociedad Matemática Mexicana. Third Series 1 Discrete and Continuous Dynamical Systems 1 Arab Journal of Mathematical Sciences ...and 28 more Serials
all top 5
#### Cited in 35 Fields
217 Operator theory (47-XX) 114 Ordinary differential equations (34-XX) 88 Partial differential equations (35-XX) 66 Quantum theory (81-XX) 27 Numerical analysis (65-XX) 26 Linear and multilinear algebra; matrix theory (15-XX) 18 Functional analysis (46-XX) 17 Fluid mechanics (76-XX) 15 Mechanics of deformable solids (74-XX) 13 Systems theory; control (93-XX) 10 Dynamical systems and ergodic theory (37-XX) 10 Statistical mechanics, structure of matter (82-XX) 9 Difference and functional equations (39-XX) 8 Calculus of variations and optimal control; optimization (49-XX) 7 Mechanics of particles and systems (70-XX) 7 Optics, electromagnetic theory (78-XX) 6 Global analysis, analysis on manifolds (58-XX) 5 Combinatorics (05-XX) 5 Functions of a complex variable (30-XX) 5 Integral equations (45-XX) 2 General and overarching topics; collections (00-XX) 2 Topological groups, Lie groups (22-XX) 2 Special functions (33-XX) 2 Harmonic analysis on Euclidean spaces (42-XX) 2 Biology and other natural sciences (92-XX) 1 History and biography (01-XX) 1 Mathematical logic and foundations (03-XX) 1 Measure and integration (28-XX) 1 Several complex variables and analytic spaces (32-XX) 1 General topology (54-XX) 1 Probability theory and stochastic processes (60-XX) 1 Statistics (62-XX) 1 Relativity and gravitational theory (83-XX) 1 Geophysics (86-XX) 1 Information and communication theory, circuits (94-XX)
#### Wikidata Timeline
The data are displayed as stored in Wikidata under a Creative Commons CC0 License. Updates and corrections should be made in Wikidata.
| 2021-06-18T08:02:59 |
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|
https://nroer.gov.in/55ab34ff81fccb4f1d806025/file/588725a3472d4a1fef8116f4
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### Restless Earth 03:
The earth was not always as it has been. It is believed that all the land was into one piece of land, known as 'Pangaea'. Later the continents were formed.
| 2020-11-28T18:06:42 |
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|
https://hero.epa.gov/hero/index.cfm/reference/details/reference_id/3221921
|
## Health & Environmental Research Online (HERO)
3221921
Journal Article
Transport of lycopodium spores and other small particles to rough surfaces
Chamberlain, AC
1967
Proceedings of the Royal Society of London. Series A, Mathematical and physical sciences
ISSN: 0950-1207
296
1444
45-70
English
Measurements have been made in the field and in a wind tunnel of the transport of Lycopodium spores to grass and other surfaces, and wind tunnel experiments also have been done with aerosols of various smaller particle sizes. The spores and other particles were made radioactive to enable the deposition of small numbers on rough surfaces to be detected. In principle the experiments in the wind tunnel were similar to those previously done with gases (Chamberlam 1966), but the mechanisms by which particles and gases are transported across the boundary layer are different. The velocity of deposition v$_g$ of the particle to the surface is equal to the terminal velocity v$_s$ if the wind speed is very small, but at higher speeds deposition by impaction on roughness elements becomes progressively more important. If the roughness elements are of a form which gives good impaction efficiency, and have a sticky surface, v$_g$ is determined by the rate of eddy diffusion in the turbulent boundary layer above the surface, and may equal or even exceed the analogous velocity of deposition of momentum. The effect of surface texture and stickiness was investigated by comparing the catch of particles on segments of real leaves with the catch on similarity shaped segments of PVC treated with adhesive. Stickiness is important in determining v$_g$ for particles of about 10 $\mu$m diameter upwards, but not for smaller particles. In the field experiments, the use of radioactive tagging enabled the presence of a few Lycopodium spores in several grams of grass or soil to be detected, and the deposition could be measured at ranges up to 100 m from the source. At low wind speeds, v$_g$ was only a little greater than v$_s$ but at higher speeds the contribution of impaction became evident. A particularly high value was obtained when the grass was wet after recent rain. The field results with Lycopodium give a ratio of velocity of deposition to wind speed of 0$\cdot$01, and this value is used to calculate the percentage of large spores or pollen grains which will travel various distances in normal meteorological conditions. It is found that the median range is about 1 km if the particles are liberated at a height of 50 cm, but 10 km if the height is 10 m. The relative importance of direct deposition to the ground and washout by ram of the air spora is considered, and is shown to depend on the effective height of the cloud of particles. For an effective height of 500 m, derived from vertical profiles of concentration observed from aircraft, it is calculated that about 25% of the total deposition of pollen grains may be in rain.
| 2020-05-31T18:43:56 |
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|
https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100N300.txt
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&EPA United States Environmental Protection Agency UJLM Source Water Protection: A Training Manual for Communities in Nicaragua A Project of the United States Environmental Protection Agency and the United States Agency for International Development ------- United States Environmental Protection Agency (4606M) EPA 816-R-02-003 www. epa. gov/safewater February 2002 Printed on Recycled Paper ------- Source Water Protection A Training Manual for Communities in Nicaragua A Project of The United States Environmental Protection Agency and The United States Agency for International Development Prepared by Horsley & Witten, Inc. ------- Table of Contents Acknowledgements Chapter 1: Introduction to Source Water Assessment and Protection in Nicaragua 1.1 Background 1.2 Introduction 1.3 Source Water Protection 1.4 The Training Manual Chapter 2: Water Quality and Community Health 2.1 Introduction 2.2 Sources and Health Effects of Common Drinking Water Contaminants 2.3 Drinking Water Standards Chapter 3: Benefits from Source Water Protection 3.1 Direct and Indirect Benefits to Human Health 3.2 Environmental Benefits 3.3 Conclusion Chapter 4: Source Water Protection Areas 4.1 Introduction 4.2 Delineating and Mapping Protection Areas for Surface Water Sources 4.3 Delineating and Mapping Protection Areas for Wells 4.4 Identifying Potential Sources of Contamination 4.5 Ranking of Potential Sources of Contamination 4.6 Conclusion Chapter 5: Developing a Community Source Water Management Plan 5.1 Introduction 5.2 A Review of the Existing Legal Framework for Source Water Protection and Management in Nicaragua 5.3 Assessing the Current State of Drinking Water Management in a Community 5.4 Developing a Consensus-Based Source Water Management Plan 5.5 Water Supply Treatment in Conjunction with Source Water Protection 5.6 Local Management of Water Supplies Chapter 6: Public Participation - A Primer 6.1 Introduction 6.2 Six Components of Successful Public Participation 6.3 Conclusion Chapter 7: Case Studies from Pilot Projects 7.1 Overview 7.2 Introduction 7.3 Ocotal 7.4 Esteli 7.5 Matagalpa Chapter 8: Innovative and Alternative Technologies 8.1 Introduction 8.2 Innovative and Alternative Technologies Applicable in Nicaragua Chapter 9: Sources of Information 9.1 Nicaraguan Local and National Government Organizations 9.2 Foreign Government and Multilateral Organizations 9.3 Non-Governmental Organizations 9.4 Educational and Research Institutions 9.5 Documents from the Pilot Projects that May Be Useful List of References Glossary of Terms Glossary of Acronyms ------- List of Figures Chapter 1 1.1 What is EPA? 1.2 What is US AID? 1.3 What is a Source Water Protection Area (SWPA)? 1.4 The Impact of Hurricane Mitch Chapter 2 2.1 Graphs of Public Water Sources in Nicaragua / Access to Drinking Services / Sanitary Disposal Services 2.2 Laboratory Capacity-Building Program for Drinking Water Quality in Nicaragua 2.3 Testing for Coliform Bacteria 2.4 What Is Total Coliform Test? 2.5 What Is Fecal Coliform Test? 2.6 Potential Drinking Water Contaminants and Contaminant Sources in the Three Pilot Project Communities 2.7 Water Borne Diseases 2.8 Metals Commonly Found in Drinking Water and their Possible Sources in Nicaragua 2.9 Special Risk of Contaminated Drinking Water to Children 2.10 pH scale 2.11 Interpreting EPA Standards and WHO Drinking Water Guidelines 2.12 Existing Legal Framework for Source Water Protection in Nicaragua Chapter 4 4.1 Paths of Water Through a Surface Watershed 4.2 Paths of Water Through a Zone of Contribution to a Well 4.3 Source Water Protection Area 4.4 Source Water Protection Area for a Well 4.5 The B oundary of a Watershed... 4.6 Delineating a Watershed for a Surface Drinking Water Source 4.7 Source Water Protection Area for a Well Based on the Calculated Fixed Radius Method 4.8 Using the Volumetric Flow Equation in the Calculated Fixed Radius Method 4.9 Candidate Source Water Protection Areas for Drinking Water Wells in Esteli 4.10 Source Water Protection Area for a Well Using the Uniform Flow Equation 4.11 Three-Tiered Source Water Protection Area for a Well 4.12 List of Potential Contaminants and Contaminant Sources for Wells in Esteli 4.13 Point Sources and Non-Point Sources of Contamination 4.14 Inventories of Potential Contaminant Sources for Four Wells in Esteli 4.15 Simple Example of a Source Water Protection Area in Which the Potential Contaminant Sources Have Been Mapped 4.16 Ranking Matrix of Potential Source and Contaminants 4.17 Representative Values for Nutrient Loading Rates for Various Sources Chapter 5 5.1 Steps to a Source Water Management Plan 5.2 Initiation of Source Water Protection in Ocotal 5.3 A Meeting of Stakeholders... 5.4 Example Management Goals and Target Dates for a Source Water Management Plan 5.5 Source Water Management Tools and Possible Implementing Agencies 5.6 Monitoring the Quality of Source Water... 5.7 Local Water Agency 5.8 Time Frame for Developing a Source Water Management Plan Chapter 6 6.1 Why Should I Protect the Public Drinking Water Source... 6.2 Public Participation in Source Water Protection in Matagalpa 6.3 Sample Press Release 6.4 Flow Chart of Pubic Participation in Source Water Management Chapter 7 7.1 Report of the Student Ecological Brigade for The Rio Dipilto during the 2000-2001 Coffee Season 7.2 Results of the Coffee Picker Surveys, May 2001 ------- Acknowledgements The Environmental Protection Agency appreciates the interest and involvement of the United States Agency for International Development in funding this project to assist Nicaragua in developing its source water protection program. EPA also thanks United States Department of Agriculture for its support and cooperation. EPA was responsible for managing funding and for significant technical input and review. Offices within EPA that contributed to the development of this project were the Office of Water and the Office of International Activities. EPA staff persons specifically involved in this work were Dr. Marilyn Ginsberg, Ron Hoffer, Stephanie Adrian, Chuck Job, and Stan Austin. EPA extends a special thank you to the individuals and organizations in the communities of Esteli, Matagalpa, and Ocotal in Nicaragua for their interest and coop- eration in establishing pilot projects upon which to base the national source water protection program. Also, EPA thanks the US AID office in Managua, and the agencies of Nicaraguan Aqueduct and Sewer Company (Empresa Nicaraguense de Acueductos y Alcantarillados), Ministry of Health (Ministerio de Salud), and Aqueducts and Sewerage of Matagalpa (Acueductos y Alcantarillados de Matagalpa) for their assistance and guidance. EPA thanks Horsley & Witten, Inc. for serving as contractors on the project, and Pan American Health Organization for providing translation and publication serv- ices for the manual. ------- 1 Introduction to Source Water Assessment and Protection in Nicaragua 1.1 Background 1.2 Introduction 1.3 Source Water Protection 1.4 The Training Manual Satellite image of Hurricane Mitch. Source: National Oceanic and Atmospheric Administration, 2001 1.1 Background The Nicaragua source water protection technical assistance project, of which this training manual is a part, stems from a Hurricane Mitch relief effort initiated shortly after that disaster struck in 1998. The two agencies primarily respon- sible for assisting Nicaragua in the development of its source water protection program are the United States Agency for International Development (USAID) and the United States Environmental Protection Agency (EPA). In conjunction with USAID, EPA has been working with three pilot project communities in Nicaragua to introduce some approaches to drinking water management used in the United States. EPA is providing technical assistance to these communities to assist them in adapting and implementing the US approaches to source water assess- ment and protection and to facilitate work in the communities to aid them in establishing source water pro- tection programs of their own. The project has culminated in the preparation of this source water protection training manual and several training sessions for people involved with water resource protection and man- agement throughout the Hurricane Mitch affected areas of Nicaragua. The objectives of the workbook are to present useful information to workshop participants on the basic ele- ments of source water protection, facilitate the development of community drinking water protection pro- grams, and enable communities to reduce the impact of future natural disasters on water supplies. The audi- ence for the manual is predominantly community leaders, regional government officials, local and national water utility representatives, engineers, health agencies, educational organizations, consultants, non-govern- mental organizations, and graduate level university students. 1.2 Introduction This training manual is about protecting the quality of drinking water sources in Nicaragua. Clean drinking water is a precious commodity. Both quality and quanti- ty issues routinely present major challenges to commu- nities. One of the difficulties in addressing these issues is the lack of 'source water protection' programs. Protection of all surface and ground water resources in Nicaragua is an admirable but unrealistic goal. However, focused efforts to protect those surface waters and ground waters that serve as sources of drinking water (generally called ' source water') is not only possible, but Protection of children's health is a major objective of vital to the health of every community. Drinking water drinking water protection efforts in Nicaragua. sources include surface waters, like rivers and streams, and ground water underneath the land surface, accessed through small community wells and larger city wells. Clean drinking water is critical to reduce, or even eliminate, the occurrence of many devastating illnesses, especially among children and the elderly. Clean water can also enhance local economies by improving the quality of life, and potentially attracting professionals and businesses to locate in an area, thereby boosting the prosperity of a community. Local com- munities in Nicaragua can play a pivotal role in protecting pub- lic health by protecting drinking water supplies from potential sources of contamination. Drinking water sources include rivers and streams. What is EPA? The EPA is an executive level agency under the Office of the President of the United States. The mis- sion of the EPA is "to protect human health and to safeguard the natural environment." Programs with- in the purview of the EPA include drinking water protection, air quality, hazardous waste cleanup, sur- face water quality, coastal resource protection, wetlands, human health, environmental management and waste management. The EPA is one of the primary governmental organizations that is responsible for protecting human health and natural ecosystems, and plays a major role in the regulation, protec- tion and improvement of the water resources of the United States. Source: EPA, 2001. Figure 1.1 ------- What is US AID? The US AID is a United States governmental agency that provides technical assistance to developing countries "recovering from disaster, trying to escape poverty, and engaging in democratic reforms." The Agency works in six areas: economic growth and agricultural development, population, health and nutri- tion, environment, democracy and governance, education and training, and humanitarian assistance. It has individual missions in many countries around the world including Nicaragua (Managua). Source: US AID, 2001. 1.3 Source Water Protection Protecting drinking water sources involves several steps, including: 1. Identifying all sources of existing or future water supplies for a community (discussed in Chapter 4). 2. Performing an assessment of those sources by: -Delineating source water protection areas (SWPAs) (discussed in Chapter 4); -Inventorying potential contaminant sources in those areas (discussed in Chapter 4); -Ranking potential contaminant sources (discussed in Chapter 4); and -Increasing public awareness/involvement (discussed in Chapters 5 and 6), 3. Developing a management plan to reduce the potential impacts of contaminants on drinking water sources (discussed in Chapter 5). These steps comprise a process called 'source water protection.' In order to achieve comprehensive source water protection, a community must identify, evaluate, and manage its source waters. Effective source water protection programs involve collaborative efforts among the people who use and impact the water resource to ensure the safety of that resource. Residents, local officials, water agencies, businesses, and farmers in a community all fall into a group of peo- ple known as 'stakeholders.' Stakeholders can repre- sent a variety of social, cultural and economic back- grounds and values, and it is essential that a source water protection program considers and incorporates these differences. While varying points of view may In order to achieve comprehensive source water protec- make consensus difficult to reach, best efforts must be tion, a community must identify, evaluate, and manage 111 made to balance opinion. its source waters. Successful source water protection requires extensive stakeholder involvement as a protection program is developed and implemented. With stakeholder involvement, everyone in a community has the opportunity to participate in shaping a drinking water protection program that best fits the needs and resources of the com- munity. A protection program developed by just a small number of individuals with minimal public partici- pation is unlikely to succeed because there is insufficient personal investment in the program by affected indi- viduals and groups in the community. A clear understanding of social, cultural, and economic differences is essential to meeting the goals of overall public participation. The general public would be unlikely to feel committed to the goals of the program. However, with extensive involvement of stakeholders in the planning process, people are far more likely to support implementation of actions to protect the drinking water supply. Source water protection is best accomplished at the local level of government. Community residents have the largest stake in protecting their own water supply. Community members can work together with local, regional, and national government agencies, taking advantage of existing governmental and non-governmen- tal programs and services to enhance drinking water protection. It is important to recognize that community drinking water sources are not governed by community bound- aries. Water sources can often be affected by activities and land uses occurring in other cities and towns with- in the same source water protection area. Therefore, cooperation with and involvement of neighboring com- munities are critical components of water supply protection. Communities often share a water source such as a river or ground water aquifer, only a portion of which is used as a drinking water supply. It is the por- tion used for drinking water purposes that must be protected from potential sources of contamination. Crop cultivation (left) is a potential source of drinking water contamination due to the use of agrochemicals With stakeholder involvement, everyone in a community has the opportunity to participate in shaping a drinking water protection program. ------- What is a Source Water Protection Area (SWPA)? A Source Water Protection Area is that land area that does one of two things: Source Water Protection Area Watershed Boundary Public Drtnklrig Water Intake Mouth of River 1. contributes overland flow of water to a stream, river, or lake that serves as a drinking water supply, or Public Drinking Water Well 2. contributes water that flows to a well that supplies drink- ing water to a population. 1.4 The Training Manual This training manual provides a step-by-step guide for communities to develop a source water protection pro- gram. It supplies information on how a community or group of communities can collaborate to develop and implement a local drinking water protection plan, and how various interest groups in communities can be involved in the process. The manual is designed as an instructional and reference guide for a variety of agen- cies, organizations and individuals interested in developing and implementing local drinking water assess- ment and protection programs in Nicaragua. The manual is based, in part, upon experiences gained in the three pilot project communities of Ocotal, Esteli, and Matagalpa. The source water protection experiences in each of these municipalities are described in detail in Chapter 7. Examples from the pilot projects are used throughout the manual to illustrate different approaches that may be useful for community source water pro- tection efforts in Nicaragua. The Impact of Hurricane Mitch The 1998 hurricane season in the Atlantic Ocean was the deadliest in over 200 years. Hurricane Mitch was the worst of the storms, a Category 5 hurricane with maximum sustained winds over 200 mph. It was responsible for more than 11,000 deaths. Nicaragua was one of the counties hardest hit by Hurricane Mitch. Torrential rains caused widespread flooding and landslides that severely affected the northwestern Pacific coast, the north-central region, and the northeastern Atlantic coast. Figure 1.3 This satellite image of Hurricane Mitch shows the immense size of the storm as it hit Central America. Source: National Oceanic and Atmospheric Administration, 2001. The aftermath of Hurricane Mitch underscored a tremendous need to develop local programs to manage and protect source waters in Nicaragua. The impact of Hurricane Mitch on Nicaragua's water and san- itation systems was tremendous. The damage and problems continued to multiply days and months after Mitch, due to the deforestation caused by the storm. Severe erosion and mudslides overloaded the already damaged water and sanitation systems. Many communities in Mitch-affected areas were with- out potable water for extended periods after the storm. The threat of waterborne disease was widespread as a result of contamination of rivers and streams used for drinking water. Figure 1.4 ------- ^^>v- - • , •-- -*. lfc " ^k^».J* *•• V-—- -.1 >; \ • "•- •-- "v' s ;" •*^^t. ^"-,1"- *V **.'^' >;~- - >^?;: -A »- * *^* • The heavy rains of Hurricane Mitch caused dramatic erosion in many streambeds (above). This erosion, exacerbated by deforestation of the hillsides contributed to contamination of surface drinking water supplies. The rainfall also washed such huge volumes of sediment into the rivers that sand removal was still ongoing in many areas (right) two years after the storm. Reconstruction projects have been undertaken to repair and replace the water and sewer systems dam- aged or destroyed by the hurricane. Emergency health campaigns helped to prevent outbreaks of waterborne diseases following the disaster. But the effects of the hurricane are still visible in Nicaragua and other regions of Central America. Much of the worst devastation following the Hurricane was felt in areas where land uses and water and sanitation services were inadequate prior to the disaster. While it would be impossible to completely control pervasive drinking water contamina- tion during a storm as destructive as Hurricane Mitch, it is possible to reduce the impact of future events, as well as to make dramatic improvements in water quality under normal weather conditions. This training manual is designed in large part to assist Nicaraguan communities as they develop their source water protection programs. These programs will provide the communities with a greater degree of resiliency in terms of drinking water quality in the event of future natural disasters like Hurricane Mitch. Figure 1.4 (continued) ------- 2 Water Quality and Community Health 2.1 Introduction 2.2 Sources and Health Effects of Common Drinking Water Contaminants 2.3 Drinking Water Standards Typical freshwater stream in northern Nicaragua. 2.1 Introduction Clean drinking water plays a very important role in the health of a community. While most cities in Nicaragua are able to provide treatment for the municipal drinking water supply, the situation is vastly different in rural areas. In rural areas, the number of residents receiving treated water is con- siderably smaller, and use of untreated drinking water supplies is common. According to the Pan American Health Organization (PAHO), approxi- mately 37 percent of the estimated total Nicaraguan population of 4.46 million people has access to treat- ed drinking water (distributed by piping systems). The urban population is estimated to be 63.7 percent 100- Q. Q. Public Water Sources in Nicaragua 70% LJ 30% Ground Water Surface Water 100- o TO n Q. 0 50- •5 n- A ccess to Drinking Services 93% 12% Urban Rural 100- % of Population 3 8 Sanitary Disposal Services 87% 54% Urban Rural of the total population, or approximately 2.84 mil- lion people (PAHO, 1999). Of that urban popula- tion, it is estimated that 93 percent has access to drinking water services, while only 12 percent of the rural population has similar access. Forty-two per- cent of the total population has access to sanitary disposal services (including the use of latrines). Of the urban population, 87 percent benefit from such services, but only 54 percent of the rural population does (PAHO, 1999). Community access to clean drinking water can be improved by protecting drinking water sources and managing them for contaminant reduction and pre- vention for both present and future uses. In 1990, 70 percent of the public water supply systems in Nicaragua used ground water, while the remaining 30 percent used surface water (PAHO, 1998). While ground water is generally more protected from con- tamination than surface water, ground water supplies can be extremely difficult to clean up once they become contaminated. They are underground and therefore impossible to see, and water underground moves relatively slowly, meaning that once contam- ination enters the ground water, it can take many years to show up in drinking water wells. These fac- tors cause ground water remediation to be very dif- ficult, and make protection of these waters from ini- tial contamination extremely important. The majority of surface drinking water supplies in Nicaragua that receive treatment uses a combination of filtration, settling basins, aeration, chemical addi- tives (to assist in contaminant removal), and chlori- nation. Chlorine is the most commonly used disin- fectant worldwide because it is highly effective against microbes, is widely available, and is inex- pensive relative to other treatment options. Water from surface sources must be filtered of sediments and organic matter prior to chlorination. Chlorination of turbid water can be ineffective and chlorine can react with the organic matter to form harmful byproducts such as trihalomethanes, haloacetic acids and chlorite (EPA, 200la). Further, the amount of chlorine needed to treat all of the harmful bacteria in turbid water can far exceed safe levels for humans. Treatment plants, such as the one in Matagalpa, also use other chemicals to remove bacteria. For exam- ple, aluminum sulfate and calcium oxide are added to the water in specified amounts during the treat- ment process, based on the quality of the influent water (Proyecto Cuencas Matagalpa, et al., 1999). These chemicals act as coagulants, and promote removal of suspended sediment, thereby enhancing the treatment process. Drinking water is aerated during the treatment process to reduce contaminate levels. Figure 2.1 Settling chambers are used to remove sediment from drinking water. It is important to note that typical water treatment systems for either surface or ground water supplies do not remove some categories of contaminants, par- ------- ticularly nitrates, organic chemicals, and dissolved metals. For example, a drinking water source con- taminated with agricultural chemicals, namely fertil- izer and pesticides, or with metals like arsenic or copper from a mining operation, would not be cleansed by treatment processes that remove microbes. Prevention and management of pollutants in a source water area, therefore, play a key role in helping to protect drinking water. For people who do not receive treated drinking water from a public water supply system, simple fil- tration methods can be helpful. A sand filter can remove many contaminants from a surface supply of drinking water, including clays and silts, some microorganisms, natural organic matter, iron, and magnesium (EPA, 1999). Sand filters can be used in individual homes or by small groups of several near- by households, as is done in some households in the Dipilto River watershed north of Ocotal. They can also be installed to serve a larger number of people, such as occupants in a hotel or workers at a coffee farm. Selva Negra coffee plantation resort in Matagalpa uses sand filtration to treat water near its source on the mountainside before it is delivered to the hotel and the workers' community. After water has been filtered, it is possible to disin- fect it in the home with chlorine, which can be pur- chased in liquid form in local stores. It is extremely important that people read, understand, and follow the directions for using this type of disinfectant because chlorine and its byproducts can be toxic to human health if used improperly (Proyecto Cuencas Matagalpa, et al., 1999). While chlorination affects the taste of water, and may be objectionable to some people, the benefits of its use far outweigh the risks of exposure to microbes in drinking water. 2.2 Sources and Health Effects of Common Drinking Water Contaminants A variety of both natural and man-made contami- nants can affect drinking water quality. Typical drinking water contaminants include microbes, Laboratory Capacity-Building Program for Drinking Water Quality in Nicaragua Water quality testing for drinking water throughout Nicaragua is generally carried out at the centralized MINSA and ENACAL laboratories located in Managua. In some areas, smaller regional laboratories perform basic water quality testing such as bacteriological tests, temperature, pH, and nitrite/nitrate tests. However, the current laboratory system in Nicaragua suffers from inadequate resources for routine test- ing and monitoring, detailed water quality testing, proper technician training, and modern equipment. A current project administered by PAHO, part of the United Nations system, is working to build the capacity of the central laboratories of MINSA, ENACAL, and a university laboratory, by providing train- ing and equipment. The laboratory capacity-building portion of this project receiving significant funding from EPA. Eventually this capacity-building program will serve as the foundation for laboratory accred- itation in Nicaragua, and capacity building in the regional laboratories. This work is part of PAHO's Regional Plan of Action to Improve Access to and Quality of Drinking Water in Latin America, which was a product of the 1994 Summit of the Americas. Similar improve- ments are being implemented concurrently in El Salvador through the same program. Figure 2.2 nitrates, solvents and petroleum products, pesticides, and metals. The relative occurrence of these cate- gories of contaminants in drinking water in Nicaragua is largely unknown because of limited water quality testing capabilities in the country. However, routine bacterial testing does occur at most if not all of municipal drinking water treatment facilities, and laboratory data generally indicate sig- nificant levels of total and fecal coliform bacteria in surface water being used for drinking water supplies. Bacterial data for ground water sources, such as in Esteli, was not available in the regional laboratory analysis data sheet provided by the Nicaraguan Aqueduct and Sewer Company (ENACAL), and may not be collected at many ground water well sites (ENACAL - Esteli, 1999). Morbidity and mortality data for water borne ill- nesses is maintained by the Ministry of Health (MINSA), and can provide some insight into the lev- els of harmful bacterial exposure possible attributa- ble to contaminated drinking water. Such data from exposure to the other types of contaminants (nitrates, solvents, pesticides, and metals) do not generally exist for Nicaragua. However, there is a reasonable likelihood that some or all of these contaminants are present in drinking water, depending on the location of the water supply and land uses in the area. Without water quality data to reveal the levels of these contaminants, it is impossible to speculate how they may be affecting the health of the population. However, general background information of the health effects of exposure to these contaminants is provided in the sections that follow. The contaminants described in this chapter are like- ly to affect water quality, to some extent, in every community in Nicaragua. The most pervasive con- taminants, based on observation of land use and human activity, are probably microorganisms and nitrates. Depending on the intensity of agricultural and/or industrial activity in a source water area, sol- vents and petroleum products, pesticides, and metals may or may not pose a significant risk to human health. The degree of risk can be determined large- ly through the source water assessment process described in Chapter 4. 2.2.A Microbial Contaminants What Are They and What Are the Sources? Sometimes open defecation takes place in unvegetated areas, where people congregate and wait. Here, coffee pickers wait for a truck to bring their bags of coffee to a drying facility. Microbes are microscopic life forms. Certain microbes normally inhabit the intestines of humans and animals and aid in digestion. While most microbes are harmless and many even perform ben- eficial functions, pathogenic microbes can cause ill- ness when ingested with drinking water or food. Harmful microbes include certain bacteria, viruses, and protozoa. These invisible contaminants can get into drinking water in several ways: • direct urination or defecation by humans and/or animals near or into a stream, river or lake used for drinking water; • discharge from a sewage treatment plant inside a source water protection area; and • overflow of waste from poorly constructed or flooded latrines in a source water protection area, especially near wells and surface waters. This drawing shows a magnified view of a bacterium, invisi- ble to the naked eye. ------- Testing for Coliform Bacteria Coliform bacteria are typically found in the digestive tract of warm-blooded animals, but can also be found naturally in the environment. Because they are generally associated with human and animal fecal matter, the presence of coliform bacteria is used as an indicator for other harmful pathogens in drinking water associated with human and animal fecal matter. Human bacterial pathogens include Escherichia coli, Salmonella spp., Shigella spp. and V. cholerae. Two tests are used to identify potential fecal con- tamination: the total coliform test and the fecal coliform test. The total coliform test is used to determine general levels of bacterial contamination while the fecal coliform test specifically indicates the presence of bacteria originating from fecal matter. Figure 2.3 What is a Total Coliform Test? The most common method of testing for total coliforms is the membrane filter method. This is a simple method that can provide results within 24 hours. To perform the total coliform test, 100 ml of water is filtered through a sterile membrane with pore diameter small enough that the bacteria remain on the fil- ter membrane. The membrane is then placed in a dish on a growth medium and incubated in a small spe- cialized oven for 24 hours. After the incubation period, each individual coliform microbe will have grown into a visible colony on the filter membrane, and can be counted. The result of the test is pre- sented as number of bacterial colonies per 100 ml of water. Typically, a drinking water supply is con- sidered clean only when zero colonies per 100 ml of water are present. (source: Madigan, et al., 2000; Gaudy and Gaudy, 1980) Figure 2.4 What is a Fecal Coliform Test? A fecal coliform test indicates only the presence of fecal coliforms, which are a subset of total coliform bacteria. Fecal coliforms grow only in the intestines of humans and animals. The membrane filter method is used for this test as well, but the growth medium and the incubation temperature are different. Bile salts are included in the growth medium so that bacteria that do not grow in human and animal intes- tines do not grow in the medium, and the incubation temperature is increased slightly. Again, results are measured in colonies per 100 ml of filtered water, and water is only considered clean if the test reveals zero colonies growing on the medium. (source: Madigan, et al., 2000; Gaudy and Gaudy, 1980) Figure 2.5 The presence of microbes in a water supply is deter- mined by laboratory tests that culture indicator bac- teria on a special growth medium (see text boxes at left). The results of these tests predict the likelihood of the presence of harmful microorganisms in the water. What Are the Human Health Effects? When certain microbes enter a human body they can cause people to get sick. Different microbes cause different illnesses. The most common illness caused by ingestion of water contaminated with fecal bacte- ria is dysentery, an infectious disease marked by dangerous hemorrhagic diarrhea. Children can suf- fer serious dehydration, and in severe cases, may even die. Other common waterborne illnesses asso- Children can suffer serious effects, particularly dehydration, from waterborne diseases. ciated with microbes in drinking water include cholera, hepatitis A, and typhoid fever (Evans and Brachman, 1991). Potential Drinking Water Contaminants and Contaminant Sources in the Three Pilot Project Communities Community Esteli Matagalpa Ocotal Potential Contaminant Solvents Petroleum Products Nitrates Bacteria Bacteria Natural Organic Material: coffee husks, honey water Pesticides Bacteria Natural Organic Material: coffee husks, honey water Pesticides Potential Source Machinery, furniture factories, auto repair shops Gas stations, factories Sewage, fertilizer Waste and wastewater Waste and wastewater Coffee processing Coffee farms, agriculture Waste and wastewater Coffee processing Coffee farms, agriculture Figure 2.6 ------- w vi Tl en su ed Cl sp di Water Borne Diseases ater borne diseases are caused by different types of microbial organisms, including bacteria, protozoa, ruses, and parasitic worms, that can be transmitted in water to humans from other humans and animals. lese harmful microbes generally thrive in the gastrointestinal tract of humans or animals and are pres- t in the environment when they are excreted. Once in the environment, these microbes have varying rvival times, but can be transmitted via surface runoff, on food, or through direct contact with infect- humans and animals (Evans and Brachman, 1991). lolera, cryptosporidiosis, typhoid fever and enteric fever caused by Escherichia coll are all commonly read via water when the diseases are present in the human population. A general list of water borne seases and information on their transmission is provided in the figure below. Common Waterborne Diseases Transmitted Through Contaminated Drinking Water Disease Cholera Cryptosporidiosis Salmonellosis Shigellosis Typhoid Fever Primary Routes of Transmission Stool to Water Stool to Water Stool to Food Stool to Human Stool to Water Urine to Water Contaminated Food Figure 2.7 Microbial contamination of drinking water poses a significant threat to human health in Nicaragua. A cholera epidemic hit Nicaragua and other Latin American countries in the early and mid-1990s. A cholera control campaign in Nicaragua, which involved improved sanitation and public education, brought the number of cholera cases back under con- trol, but only after the control campaign was again challenged by Hurricane Mitch in 1998. In 2000, the number of reported cases of cholera in Nicaragua was down to eleven (PAHO, 2001). According to MINSA, however, dysentery remains a threatening public health problem in Nicaragua (MINSA, personal communication, November, 2000). In 1990, for example, the number of report- ed deaths due to diarrhea was 2,166 (PAHO, 1998). The numbers of reported cases of diarrhea in 1993 and 1994 were 255,000 and 264,366, respectively (PAHO, 1999). It can be reasonably assumed that a large proportion of these cases is attributable to ingestion of contaminated drinking water, as opposed to poor hygiene or contaminated food, although the exact proportion is unknown. By 1996, the number of reported deaths due to diarrhea had been reduced to just 82 due to national control efforts (PAHO, 1999), but the number of cases con- tinues to be high. Intestinal infectious diseases like dysentery and cholera are of additional concern because they are among the leading causes of death of children under one year of age (PAHO, 1998). Of the 2,166 report- ed deaths from diarrhea in Nicaragua in 1990, 75 percent were children under the age of one (PAHO, 1998). Source water protection can play an integral role in the prevention of outbreaks of disease, such as dysentery and cholera, caused by microbial contam- ination of drinking water and food. Cholera and dysentery can be propagated through both inade- quate sanitation and contaminated drinking water. Managing land uses, identifying and managing potential contaminant sources, and planning for the future can all contribute to reduced risk to these dis- eases and can help to limit the magnitude of future disease outbreaks. 2.2.B Nitrates What Are They and What Are the Sources? Nitrates are molecules comprised of nitrogen and oxygen in the chemical form NO3. Nitrates are nat- urally occurring in low levels in the environment as part of the nitrogen cycle. The greatest sources of nitrates are agricultural fertilizers, but human and animal wastes can also contribute nitrates to the environment. Nitrates can affect both surface and ground water drinking supplies. Treating drinking water contami- nated with nitrates is expensive, and can be compli- cated by the presence of other types of contaminants. While nitrate concentrations can vary over time due to atmospheric sources, agricultural inputs, and weather conditions, it is reasonably safe to assume that nitrates are affecting drinking water quality in Nicaragua, and should be a target of source water management efforts. Cattle wastes washing into rivers and streams are a significant source of nitrogen and bacterial input to drinking water supplies. ------- What are the Human Health Effects? Elevated levels of nitrates in drinking water are of concern because of their potential effect on infants, young children, and pregnant women. Nitrates above 10 mg/1 in drinking water can cause blue baby syndrome (methemoglobinemia), an illness charac- terized by oxygen starvation in the blood, which can lead to mental retardation and, in severe cases, even death. Ingesting nitrates is also associated with ele- vated cancer risk, especially gastrointestinal cancers. 2.2.C Solvents and Petroleum Products What Are They and What Are the Sources? Some businesses and industrial operations use petro- leum-based chemicals or man-made organic sol- vents in the course of performing their work. For example, automotive repair shops often use and dis- pose of a variety of solvents or petroleum prod- ucts including motor oil and degreasers. Painting opera- tions use paint thinners, varnish- es, oils and stains. Gas sta- tions store and deliver fuel. All of these materials can pollute drinking water if they are not handled, stored, or disposed of safely. What Are the Human Health Effects? Solvents can pose significant health risks to people of all ages, especially when ingested routinely over long periods of time, even at seemingly low concen- trations. Many organics are associated with an increased risk of cancer in all age groups. They are also linked to liver problems and can impair the nor- mal function of the circulatory and nervous systems. Women may experience reproductive difficulties, and children are at a high risk of developing a spec- trum of health problems related to exposure to these chemicals in drinking water (EPA, 200Ib, online: www. epa.gov/safewater/mcl. html). 2.2.D Pesticides What Are They and What Are the Sources? A pesticide is "any substance or mixture of sub- stances intended for preventing, destroying, repelling, or mitigating any pest" (EPA, 200Ic). Pesticides include insecticides, which are intended to kill or repel insects; fungicides, which are intend- ed to kill fungi; and herbicides, intended to kill unwanted weeds and plants. In Nicaragua, common pesticides include gramoxone (a herbicide), methamidophos (an insecticide), endosulfan (an insecticide), and metalaxyl (a general use fungicide). When chemicals such as these are used to control weeds and insects in crop production or to control household pests, they can contaminate drinking water supplies either by way of disposal or in runoff. The active ingredients in most pesticides are usually either synthetic organic compounds (such as those Ridomil is a trade name for Metalaxyl, a fungicide used on crops in Nicaragua. listed above), or toxic metals, like copper or arsenic (use of arsenic was more common in the past than it is today). These chemicals are poisonous to humans and can cause short-term effects like headaches, nausea and vomiting, and/or long-term impacts like nervous system damage and cancer. What Are the Human Health Effects? The health effects of exposure to pesticides through ingestion in drinking water are similar to those of sol- vents. Pesticides are also organic chemicals, and the health effects are often similar. Liver and kidney prob- lems, as well as increased cancer risk, have been connected to pesticide exposure through drinking water (EPA, 200Ib). Children are especially at risk when they routinely ingest significant concentrations of pesticides in drinking water. There are "critical periods" in human development when exposure to a toxin is particularly damaging. For example, pesticides may harm a child by blocking absorption of important food nutrients necessary for normal healthy growth. Also, if a child's excretory system is not fully developed, the body may not fully remove pesticides. (EPA, 200Id) 2.2.E Metals What Are They and What Are The Sources? Metals can occur naturally in drinking water sources by leaching from the soil. Metals are also associated with a range of human sources including urban stormwater runoff, industrial or domestic wastewater dis- charges, oil and gas production, mining, and farming. In acidic soil conditions (low pH), metals that are clinging to sediments from natural or human sources can be released into ground and surface water by leach- ing from the soils. These metals include naturally occurring trace elements such as lead, mercury, iron, and copper. Concentrations of these metals at greater than trace levels are often associated with industrial or min- ing agriculture. Metals in drinking water can also originate from organometallic compounds used in organic pesticides (for example, the fungicide copper sulfate) or from wood and leather preservation processes (which often use tin or arsenic) (Manahan, 1994). Lead and other metals can also leach from old water distribution pipes when drinking water is very acidic (low pH). What Are The Human Health Effects? Although at low levels metals are important in the human diet, at high levels they can be dangerous to human health and the envi- ronment. Metals can be a serious source of contamination in drink- ing water. Once metals are dissolved in water, they become avail- able for biological uptake. Metals above standards can be toxic to aquatic life, and can have significant negative human health effects when ingested through drinking water. Some metals can interfere with human and animal nervous system function and others can cause reproductive and developmental problems. For example, inorganic arsenic in drinking water is associated with high inci- dences of skin cancer and other cancers (WHO, 1993). Copper can have gastrointestinal effects, although the exact levels above which adverse human health effects are seen are not well defined. Lead can accumulate in the human skeleton and can inhibit enzyme development and calcium metabolism in infants and children. Lead is also toxic to the Mining operations can be a source of metals in drinking water. ------- central and peripheral nervous systems (WHO, 1993). While the most common source of lead in drinking water is plumbing and distribution pipes, additional industrial sources are possible and should be managed (WHO, 1993) Metals Commonly Found in Drinking Water and their Possible Sources in Nicaragua pH Scale Metal Arsenic Cadmium Copper Lead Effects of ingestion in Drinking Water Skin damage, circulation system problems, increased risk of cancer Kidney Damage Short term exposure: gastrointestinal distress; Long term exposure: liver or kidney damage Infants and children: delays in physical or mental development; Adults: kidney problems, high blood pressure Sources in Nicaragua Erosion of natural deposits, mining byproduct, runoff from glass and electronics production wastes Corrosion of galvanized pipes, erosion of natural deposits, discharge from metal refineries, leachate from disposed batteries and paints Corrosion of household plumbing systems, erosion of natural deposits, mining byproducts Corrosion of household plumbing systems, erosion of natural deposits Figure 2.8 Special Risk of Contaminated Drinking Water to Children Diseases and ailments caused by exposure to various contaminants typically pose a greater risk to chil- dren than to adults. Infants and children may be especially sensitive to health risks posed by organic chemicals (solvents, petroleum products, and pesticides) and metals for several reasons: • their internal organs are still developing and maturing; • in relation to their body weight, infants and children eat and drink more than adults, potentially increasing their exposure to chemicals in food and water; and • certain behaviors, such as playing on floors or treated outdoor areas, or putting objects in their mouths, increase children's exposure to chemicals used in homes and neighborhoods. Figure 2.9 pH is a measurement of the acidity of a substance, based on the concentration of hydrogen ions pres- ent. It provides an understanding of the general conditions in the medium being tested, for exam- ple, soils, streams and ground water. pH is present- ed on a log 10 scale from 1 to 14, with neutral being pH 7. The pH of natural surface water and ground water vary considerably from one location to another due to the natural conditions of the area, but monitoring of pH changes can provide a good indication of possible contamination of a water source. Figure 2.10 Gastric Fluids Volcanic Soils Acid Mine Drainage Orange Juice Tomato Juice Acidic Soils Cabbage Urine Pure Water Sea Water Baking Soda Alkaline Soils Ammonia Solution Soapy Water Bleach Liquid Drain Cleaner 2.3 Drinking Water Standards Most countries seek to protect public health by setting legal stan- dards for drinking water quality. In the United States, drinking water suppliers are required to test for an extensive list of pollu- tants ("priority" pollutants) on a routine basis, and if a violation of a standard is reported, corrective measures must be taken. Both the EPA National Primary and Secondary Drinking Water Standards under the Safe Drinking Water Act (passed in 1974 and amended in 1986 and 1996; EPA, 200la online) and the World Health Organization (WHO) Guidelines for Drinking Water Quality (original version published in 1984 and 1985 and revised edition published in 1993 and 1996; WHO, 1996) can be used as references for safe drinking water standards for common contaminants. These standards provide a basis on which govern- ments worldwide can manage, monitor and regulate drinking water quality for the protection of human health. Both documents are available on the internet. The EPA Primary and Secondary Drinking Water Standards can be located on the internet at www.epa.gov/safewater/agua/estandares.html. The World Health Organization Drinking Water Guidelines can be found on the internet in English at www.who.int/water_sanitation_health/GDWQ. ------- Interpreting EPA Standards and WHO Drinking Water Guidelines The units of measure applied to both the EPA standards and WHO guidelines are "parts per million" (ppm, also expressed as milligrams per liter or mg/1) and "parts per billion" (ppb, also expressed as micrograms per liter or mg/1). These concentrations are extremely minute. One part per million can be thought of as the equivalent of one minute in two years. One part per billion can be thought of as one second in 32 years. Yet, these minute concentrations are the levels at which impacts to human health have either been documented or extrapolated from research, based on an average person's daily exposure to the contaminants through drinking water (WHO, 1996). It is therefore important to be mindful that even small quantities of certain chemicals entering water can contaminate a large volume of drinking water. With regard to bacterial contaminants, the drinking water standards are commonly described in number of organisms per 100 milliliters of water (the amount which is commonly filtered for the test). Both the EPA Drinking Water Standards and the WHO Guidelines set the limit of fecal coliforms and other microbes in drinking water at zero (undetectable). While contact with just a single disease organism can cause disease, the higher the concentration of that organism in a volume of drinking or bathing water, the higher the risk of contracting the disease with which that organism is associated. Testing for viruses and protozoa is not common, as the tests are specialized and expensive. MINSA is responsible for defining the national drinking water quality standards in Nicaragua for all pub- lic supplies of water, such as those managed by ENACAL. Water quality testing is carried out at the national water quality laboratory in Managua as well as at several smaller regional laboratories. While improvements to Nicaragua's laboratory capacity are in process (see "Laboratory Capacity-Building Program for Drinking Water Quality in Nicaragua" in this chapter), the quality of all public drinking water in Nicaragua can still not be ensured up to the standards. This is a primary reason in support of a source water protection program in Nicaragua. Data collected by MINSA show that surface water entering the Ocotal treatment plant from the Rio Dipilto exhibits bac- terial contamination. Figure 2.11 Existing Legal Framework for Source Water Protection in Nicaragua Several national laws in Nicaragua outline the potential significant roles of other agencies in source water protection in Nicaragua. These laws are described in more detail in Chapter 6, but are summarized here: • The Ley 290, the Ley de Organization, Competencias y Procedimientos del Poder Ejecutivo (1998), out- lines the responsibility of all national government agencies. • Ley 217 , the Ley General del Medio Ambiente y los Recursos Naturales (1996), establishes the respon- sibility of the Ministry of Environment and Natural Resources (MARENA) for regulating and setting national environmental standards. • Decree Number 33-95, Disposiciones Para el Control de la Contamination Provientes de las Descargas de Aguas Residuales Domesticas, Industriales, e Agropecuarias (1995), sets maximum limits on various contaminant concentrations in the discharge of different categories of household, industrial and agricul- tural wastes into sewer systems and surface waters. Figure 2.12 ------- Benefits from Source Water Protection 3.1 Direct and Indirect Benefits to Human Health 3.2 Environmental Benefits 3.3 Conclusion Clean water is fundamental to the health of human populations and ecosystems. Beyond the benefit to public health, there are a number of economic, social and environmental advantages stemming from source water protection. However, accounting for all the advantages of source water protection in economic terms is dif- ficult, and the human benefits provided by an unimpaired water supply are rarely explained in the tradition- al form of economic valuation. Consequently, clarifying the benefits of source water protection is usually done in a qualitative rather than quantitative manner. 3.1 Direct and Indirect Benefits to Human Health The most obvious benefit of clean drinking water is maintaining public health. Water-related diseases worldwide are estimated to cost at least $125 billion/year in direct medical expenses and lost work time (Gleick, 1998). While improved management of potential contaminant sources will not remove all sources of contamination, it can significantly reduce them. A reduction in contaminants affecting the water resource under- Source water protection can benefit standably then translates into a reduction in both direct and indirect costs coffee workers and others by improv- attributable to drinking water contamination. inS drinking water quality and reducing risks of some illnesses. 3.1.A Family Benefits The social benefits of source water protection are best expressed in terms of avoided impacts and their asso- ciated costs. Generally speaking, an increase in water quality can be expected to result in a decrease in dis- ease, especially in infants, children and the elderly. Costs associated with treating disease, including travel to medical facilities, time away from work, and the cost of medication, can be very burdensome, especially among impoverished or low-income families and individuals. According to PAHO (1998), the average cost per patient to provide health care services and drugs per illness episode was estimated at 30 cordobas for chil- dren ages 0-5 years and 65 cordobas for children over 6 years of age. Depending on the illness, the govern- ment health center may bear much of the cost, although in some cases the patient's family must bear the bulk of the health services cost. Whether paid by the government or patients, the costs of water borne diseases in Nicaragua are sig- nificant. The average per capita income in 1999 was just less than 4000 cordobas, or approximately US$300 (World Bank, 2001). The annual per capi- ta cost of medical attention resulting from contami- nated drinking water could be as much as one to even five percent of the average per capita income, depending on the number of medical visits required in a year (World Bank, 2000). Many drugs used to target diseases such as tubercu- losis, malaria, dengue, and sexually transmitted dis- eases, as well as drugs to improve the health of mothers and children, should be available free of charge at local health centers (PAHO, 1998). However, the availability of drugs in 1996 averaged only between 60 and 70 percent of the actual need (PAHO, 1998). Clearly, a reduction in illnesses can reduce the strain on an already limited supply of drugs, save significant expenses, and reduce demand on the limited number of trained medical technicians (tecnicos) in the country. Clean water is fundamental to the health of human populations and ecosystems. Illness has other implications for families as well. It can cause both physical and emotional stress, espe- cially if a family member needs care for an extend- ed time. Care requirements for an ill child or an elder are likely to preclude carrying out of regular household duties or earning daily wages to support a household. Family income can be reduced at the same time that money is needed for medical expens- es. School attendance can also go down due to ill- ness or to the need to care for a family member with an illness. Protecting drinking water sources from contamina- tion could reduce the illness-related costs to fami- lies. When the savings to an individual household due to availability of clean water are multiplied across a community or watershed, the total econom- ic value is considerable. 3.1.B Community Economic Benefits Effective water resource protection at the commu- nity level can provide a stimulant to the economy at both local and national levels. Ecotourism could be advanced in areas with safe drinking water. ------- For example, dependable potable water and an effi- cient drinking water delivery system may increase the potential for investment by foreign or domestic companies seeking locations with a solid infrastruc- ture. Well-protected and well-managed drinking water sources also increase the overall quality of life in a community, and can enhance recreational values in a source water area. Healthy and inviting surface waters (rivers, streams, lakes) provide opportunities for fishing, swimming and bathing. Ecotourism can be advanced as a potentially prosperous business venture if people know there are recreational oppor- tunities and access to a safe source of drinking water in an environmentally attractive area. Property val- ues may also increase over time with improvements in the quality of both surface and ground water resources. Finally, source water protection reduces the need for water treatment. The cost of maintenance and repairs for a community drinking water treatment plant that is stressed by excessive levels of contami- nants can be disproportionately high. Source water protection can help reduce suspended solids in a river (caused by erosion) as well as bacterial loading from livestock and open human defecation. Sediment loads can interfere with the efficiency of a treatment plant, as can sporadic excess loads of bac- teria. Good management of a surface source water protec- tion area can reduce the potential for excessive loads of pollutants to a river. It can also result in more consistent water quality conditions in a surface water source, and thus help ensure efficient and cost- effective operation of the treatment facility. Source water protection for drinking water wells can also be effective in reducing water treatment needs and associated costs. Chemicals, such as petroleum products or solvents, that may leach into the ground from surface spills, gas stations and other potential sources can eventually reach ground water. Leaders involved in source water protection efforts may enhance their capacity to accom- plish other key tasks in a community. Ground water contaminated by these chemicals can be very expensive to treat, and in some cases may render a drinking water source unusable. By pro- tecting the area around a drinking water well, the risks of serious contamination and associated treat- ment costs can be minimized and the source of drinking water can be conserved for long-term use. In areas such as Esteli that depend primarily on ground water pumped through a series of wells located throughout the city, the benefits of source water protection are readily apparent. 3.1.C Capacity Building Benefits The process of source water assessment and protec- tion can build significant capacity to address other important local issues. Protecting source water is a broad, long-term community undertaking that requires establishment of a comprehensive network of stakeholders. The gains earned from forging ties among stakeholders, including individuals in the community, non-governmental organizations, business associations, schools, and governments, can be sig- nificant and enduring. Leaders involved in directing a source water protection program may gain sufficient political standing to accomplish other key tasks within a community. Also, the benefits of successful source water protection in one town can inspire other communities, thereby broadening the impact of one commu- nity's success. 3.2 Environmental Benefits While this manual focuses predominantly on source water protection for the purpose of improving drinking water quality, there are considerable environmental gains to be achieved from safeguarding water resources. A healthy ecosystem able to support the array of flora and fauna native to Nicaragua, generally requires a water source free of significant pollution. When overland flow of water picks up excessive levels of nutrients, chemicals, or harmful microorganisms on its way to join a river or stream, environmental problems can result. Unnatural constituents in water can cause an imbalance in the aquatic environment that may become evident through a change in the animal or plant community, loss of one or more species, and/or an overabundance of one species or group of species, for example an algal bloom. The Lago Puerto Viejo along the Pan American Highway north of Managua is an example of a surface water ecosystem experiencing an overgrowth of aquatic vegetation. The overgrowth is most likely due to an exces- sive amount of nutrients (probably phos- phorous) in the surface water and/or ground water entering the lake. It can be reasonably assumed that the excess nutri- ents are coming from fertilizer used on surrounding agricultural land. While water quality tests could help character- ize the condition of the aquatic environ- ment, the thick coverage of aquatic vege- tation likely indicates the lake is eutroph- ic, meaning that it suffers from an accel- erated growth rate of aquatic plant species. Eutrophication leads to oxygen- starved conditions in a surface water body. It is often true that highly eutro- phied lakes such as Lago Puerto Viejo are unable to support normal populations of fish, amphibians plants. and native aquatic Lago Puerto Viejo If surface runoff rainwater infiltrating the ground picks up contaminants from a chemical dump or from mine tailings for example, it can carry those materials into the ground water system. When contaminated ground water discharges to a lake, stream, river, or even the ocean, it can damage ecosystems in the receiving waters. In general, ecosystems free of significant contaminant stress are more healthy than contaminated ecosystems, and therefore are better able to provide a normal range of natural benefits. ------- 3.3 Conclusion Source water protection has significant human health, economic, social and environmental benefits. A com- munity with safe drinking water is a more healthy community, experiencing fewer social costs associated with illness and enjoying more potential for economic well-being. Source water protection efforts can result in immediate benefits, especially if a single problematic contaminant, such as bacteria, is identified and signif- icantly reduced. The greatest advantage of these efforts, however, is the potential for long-term protection of drinking water sources. A comprehensive source water protection program can improve the quality of life for individuals, families, communities, and the nation for generations to come. ------- Source Water Protection Areas 4.1 Introduction 4.2 Delineating and Mapping Protection Areas for Surface Water Sources 4.3 Delineating and Mapping Protection Areas for Wells 4.4 Identifying Potential Sources of Contamination 4.5 Ranking Potential Sources of Contamination 4.6 Conclusion What is a Source Water Protection Area? A Source Water Protection Area (SWPA) is defined as the area that supplies water to a public water supply, ground water well, or sur- face water intake. It is this area through which contaminants are likely to pass and eventually reach the ground water well or sur- face water intake. The SWPA can be delineated using one of sever- al methods, which are described in Sections 4.2 and 4.3. 4.1 Introduction The first step in protecting drinking water is to identi- fy the geographic area(s) that provide drinking water to a river intake or to a well. Such an area is either 1) the watershed area contributing water to that part of a river or stream that is used as a source of drinking water, or 2) a zone of contribution to a well (that is, the land area beneath which water flows to a well that extracts drinking water from the underground aquifer). After rain water reaches the earth's surface, it gener- ally either seeps into the ground to the underlying aquifer (recharge) or flows overland (runoff) into the nearest downstream surface water body (see Figure 4.1). Protecting source water requires consideration Watershed Boundary Precipitation UH of the entire watershed area, or the zone of contribu- tion through which potential drinking water flows before it is withdrawn from a river or public well. The simplest way to protect drinking water is to pro- tect and manage the way land is used within the SWPA. The first step in protection is to delineate the source water area and show it on a map. For exam- ple, Figures 4.2 and 4.3 show the source water pro- tection area for a surface water source (an intake on a river), and the source water protection area for a ground water source (a well) respectively. These maps provide a candidate SWPA for each drinking water supply. Figure 4.1 Paths of Water Through a Watershed Watershed Area Boundary Source Water Protection Area Watershed Boundary Public Drinking » Water Intake Source Water Protection Area for a Well Well Figure 4.2 Figure 4.3 What are Watersheds and Watershed Areas? Watershed: The land area (sometimes referred Watershed Area: The land area from which to a drainage basin) from which water drains water drains to a point on a receiving body of into a receiving body of water (including lakes, water (Figure 4.2). ponds, wetlands, embayments, estuaries, and oceans) or to the terminus of a river, stream, or tributary (Figure 4.4). 1 Overland Flow \2 Ground Water Flow \3 Shallow Subsurface Stormflow ------- 4.2 Delineating and Mapping Source Water Protection Areas for Surface Water Sources Source water protection areas for surface water and ground water sources are delineated using different methods. The boundaries of a surface watershed are sometimes obvious. Often, the hills or mountains surrounding the drainage basin form clear bound- aries and the shape of the watershed can be easily visualized. Where the watershed boundary is less easily visualized, a topographic map is used. The boundary of a watershed can be defined by asking for any point X on the map: "If a drop of water falls here, will it eventually flow to the mouth of the river or stream of concern?" The answer can be determined by tracing the flow path of the drop from higher elevations to lower ele- vations, its direction always staying perpendicular to topographic con- tour lines. If the answer is yes, then that point is within the watershed. If the answer is no, then that point falls outside. However, it is impor- tant to note that every point falls within some watershed, even if it is not the current watershed of concern. Figure 4.4 illustrates this point. Figure 4.4 The boundary of a watershed can be defined by asking, "If a drop of water falls to the ground at point X, will it eventually flow into the river or stream of concern?" How are watershed area limits drawn for surface water sources? First, the point along the surface water body that marks the drinking water intake is located on the topographic map. All of the land uphill from this point, and from which water drains, is the watershed area. This is com- monly a subset, or sub-watershed, of a larger watershed associated with an entire river. The upper boundary of the watershed area coincides with the boundary of the watershed (Figure 4.5). The boundary along the down gradient edge of the SWPA will be estimated using a topographic map as a reference. All the water in the watershed area will flow down gradient through this single point. Starting at the intake location, a line is drawn along the land surface that is directly perpendicular to every contour line on the topographic map. The upper boundary of the water- shed area will likely be easily defined based on topography. The down gradient boundary will likely have to be estimated since this boundary does not usually coincide with the natural watershed boundary. Figure 4.5 illustrates this point. In some cases, the available topographic maps may not present enough detail or may not be at a scale useful to delineate the watershed area. In these cases, individuals will need to visit the stream and tour the water- shed in order to estimate the boundaries of the watershed area based on observation. Watershed areas can be subdivided to facilitate different levels of pro- tection. In general, those portions ('sub areas') closest to the drinking water intake will have the shortest travel time and the shortest distance over which particulates may be naturally removed, and therefore might be placed under a higher level of protection or management. Definition of sub-areas allows communities to prioritize protection and manage- ment activities within the watershed area. Other criteria that can be used to subdivide protection areas include soil type, vegetation and slope of the ground within the SWPA. 4.3 Delineating and Mapping Source Water Protection Areas for Wells Many public water supplies are wells that pump water from a ground water aquifer. For example, the community of Esteli pumps its drinking water from a series of 16 wells that are located in and around the city. As in most urban centers, these wells are susceptible to contaminants from surface activities and land uses, such as oil from cars and buses, pesticides and fertilizers from local agricultural fields, or release of industrial chemicals. Discharges of pollutants from land uses at the sur- Source Water Protection Area Watershed Boundary Public Drinking • Water Intake Mouth of River Figure 4.5 Delineating a watershed for a surface drinking water source. The area contributing to a surface water intake is commonly a subset of a larger watershed. face can mingle with rainwater as it infiltrates downward and reaches the aquifer, possibly having a negative effect on the quality of drinking water pumped by the wells. When a well is pumped, it pulls water from the underground aquifer, causing water surrounding the well to move towards the well. Water that falls on the land surface and recharges the aquifer may eventually get pumped back out of the ground through a well. The land area that contributes water to the well is the zone of contribu- tion for the well. Figure 4.6 is a very simplified cross sectional diagram showing how water flows through a zone of contribution to a well. Using information about the physical characteristics of the aquifer, the rainfall and recharge rate (how fast the water seeps into the soil and reaches the aquifer below) in the local region, and the rate of pumping of the well, we can estimate the boundary of the well's zone of contri- bution, which may serve as the source water protection area (SWPA). ------- Figure 4.6 Paths of Water Through a Zone of Contribution to a Well The following methods are applicable to places like Esteli where there are sand or sand and gravel aquifers. In other places where the aquifers are frac- tured rock, mapping source water protection areas for wells is more difficult. Extensive drilling and geophysical investigation are required to accurately understand the subsurface network of rock fractures that may hydraulically connect to a given drinking water well. However, this manual does not go into detail on methods to accurately delineate source water protection areas for wells in these circum- stances. The amount of investigation and analysis required is beyond the scope of this training. In the United States, some states have faced this problem. In general, the United States program recommends using a 1/4 mile (approximately 400 meters) radius until more site-specific information can be gathered. Source Water Protection Area for a Well Based on the Hydrologic Balance Equation in the Calculated Fixed Radius Method Well Pumping (Q) = Recharge (R) edge of the pumping rate of the well and the recharge rate for the aquifer. The recharge rate can often be estimat- ed by determining the annual rainfall and subtracting estimates of evapotran- spiration (evaporation plus the transpi- ration from plants) and surface runoff over the course of a year. The radius of the circle that defines the protection area is determined by the following equation: Figure 4.7 1. Calculated Fixed Radius. In these methods of delineating source water protection areas for a well, a circle is drawn around the well based upon hydro- logic data, such as recharge rate or time of travel of ground water. One calculated fixed radius method is based upon a hydrologic balance between the pumping rate and the recharge rate. This method uses a simple equa- tion based on the volume of water drawn to the well during a specified time period, and requires knowl- r= yQ/Rn Where r = radius of the protection area (feet) Q = well pumping rate (cubic feet/year) R = recharge rate (feet/year) Another type of calculated fixed radius method uses the volumetric flow equation. This equation allows the volume of the aquifer from which water flows to a pumping well, over a specified amount of time, to be calculated. Based on that volume, the correspon- ding radius of the protection area on the ground sur- face can be determined. If the goal is to protect the (Further information may be found at the EPA web- site (www.epa.gov)). A number of different methods may be used to delin- eate source water protection areas for wells (that is, the zone of contribution of ground water to a well). Usually, the method that is used will depend on the amount and types of data that can be obtained, as well as the availability of a technical staff. Delineation methods include: • Calculated Fixed Radius • Analytical Methods • Numerical Methods • Hydrogeologic Mapping dcy X wellhead from specific known contaminants, the travel time can be specified to correspond with the probable decay rate or sorption rate of a contaminant of concern so that the amount of contaminant that reaches the well is minimal or zero. However, little is known about these rates in ground water. Therefore, communities often base protection radii on management priorities. In the U.S., a communi- ty can use radii that coincide with a estimated travel times of the ground water that are considered to be reasonably protective. These travel times are 2 years (especially when the concern is coliform bacteria) or 5 or 10 years when other contaminants are the pri- mary concern. Use of the volumetric flow equation requires knowl- edge of the pumping rate of the well, the travel time for water to reach the well, the porosity of the aquifer (determined by type of material in the All of these methods are described briefly here, but we will only provide detailed examples of the first two methods. These first two methods are common- ly used and provide a very useful starting point for community-based source water protection. The remaining two methods require a great amount of data, technical skill, and computer modeling, and are therefore less easily implemented. H Figure 4.8 Volume of Aquifer Needed to Supply the Well, Using the Volumetric Flow Equation in the Calculated Fixed Radius Method aquifer), and the length of the well screen (from well construction records). The volumetric flow equation can be used in the following form to determine the radius of the protection area: r = Qt nH Where r = radius of the protection area Q = well pumping rate (feet) t = travel time to well (years) (based on community's management priorities) n = porosity of the aquifer H = length of the well screen (feet) 3 ------- Candidate Source Water Protection Areas for DrWking Water Welte\in Esteli University students in Esteli have delineated candidate SWPAs for all 16 drinking water wells in the city. They worked with representatives from ENACAL to gather data on locations of the wells and pumping rates, and estimat- ed the rate of recharge of precipitation to be about 50 per- cent of the total rainfall in the region. These SWPAs are only suggestions and have not been adopted as legally recognized protection areas. Figure 4.9 ------- 2. Analytical Methods. A number of analytical methods have been developed to predict the ground water flow patterns surrounding a pumping well. Analytical methods often require the input of hydro- geologic parameters, for example, transmissivity, porosity, hydraulic gradient, hydraulic conductivity, and saturated thickness of the aquifer. Analytical methods generally involve computer modeling. These methods simulate the movement of ground water as a function of pumping rates, aquifer char- acteristics and water table conditions. One type of analytical method that utilizes the uniform flow equation has been commonly used. This equation, like other analytical methods, requires more detailed hydrogeologic data than the previous method. Specifically, the pumping rate of the well, the hydraulic conductivity of the aquifer, the saturated thickness of the aquifer, and the hydraulic gradient of the aquifer are required data. This equation pro- vides the down-gradient (XL) and lateral limits (YL) of the protection area around the well. The uniform flow equation can be solved for the down-gradient and lateral limits of the protection area, as shown below: X, =- Q Equipotential Lines Flow Lines - -K Y, =± 2nKbi Q 2Kb! Figure 4.10 Source water protection area for a well using the uniform flow equation Where: Q = Pumping rate of well (cubic feet/day) K = Hydraulic conductivity (feet/day) b= Saturated thickness (feet) i = hydraulic gradient (rise/distance) The uniform flow lines (Figure 4.10) indicate the direction of flow of the ground water. The equipo- tential lines indicate lines of equal water table eleva- tion within the ground water aquifer. The line inter- secting the equipotential lines at right angles and passing through the three points designated on Figure 4.10 (XL, -YL, and +YL) forms a parabola that delineates the down-gradient and lateral limits (that is, the ground water divide) of the protection area. The method does not indicate where the up-gradient limit is located. One way to estimate the up-gradient limit is to combine this method with the calculated fixed radius approach. The up-gradient boundary of the protection area calculated by the uniform flow equation would then be located where the area of the entire protection area is equal to the area calculated using the calculated fixed radius method. 3. Numerical Methods. Numerical methods gen- erally require a computer program and more exten- sive field data. These methods allow for two- and three-dimensional modeling of aquifers. The study area is divided into a computer-generated grid to which values of water table elevation, hydraulic con- ductivity, and aquifer thickness are assigned. The model then simulates changes in the water table ele- vation in each grid in response to pumping of the well. The resulting depression in the water table is then used to delineate the protection area. An exam- ple of a computer model that uses numerical meth- ods is MODFLOW, a frequently used program developed by the United States Geological Survey (USGS) to simulate ground water flow. This method requires specialized expertise in hydrogeologic and computer modeling, and may, therefore, be imprac- tical for most communities. 4. Hydrogeologic Mapping. Hydrogeologic map- ping can be used to map flow boundaries based on geologic, geomorphic, geophysical and dye-tracing information. Because of these requirements, it is best suited to smaller aquifers with near-surface flow boundaries. This method requires specialized expertise in geological and physical mapping, dye tracing methods, and flow boundary analysis and may therefore be impractical for most communities. Source water protection areas for wells can also be delineated using a combination of the methods pre- sented above. This approach may be helpful in des- ignating different levels of protection within the overall protection area. For example, Figure 4.11 shows a three-tiered source water protection area for a well. Zone I represents an arbitrary fixed radius at 100 meters. Zone II is based on an analytical flow model, and Zone III is based on hydrogeologic map- ping. It is important to note that the candidate SWPAs for wells can overlap with one another or can be too large for a community to effectively manage. For example, in the case of the candidate SWPAs delin- eated by the university students in Esteli, the SWPAs overlap such that almost the entire land area of the town would fall within a protection area (see Figure 4.9). As a result, management of these SWPAs may prove very difficult. In order to balance the size of a SWPA with the effective manageability of the SWPA, it may be necessary to alter the delineation method or assumptions in order to decrease the area of the candidate SWPA(s) by reducing them before they are finalized. Zone I- 100m radius Zone II - Primary recharge area _ _i Zone III - Secondary recharge Figure 4.11 Three-tiered source water protection area for a well. 4.4 Identifying Potential Sources of Pollution Once the protection area around a community drink- ing water source has been delineated, the next step is to identify and map the potential contamination within the protection area. Common potential sources of contaminants in the pilot project commu- nities, and probably in many communities in Nicaragua, are manure from livestock (especially cattle), pesticides and fertilizers from agricultural fields, solvents and petroleum products from auto- motive repair shops or garages, and discharge water and coffee husks from coffee processing facilities. Potential sources of contaminants can be identified by researching and observing the activities that occur within a mapped source water protection area ------- List of Potential Contaminants and Contaminant Sources for Wells in Estelf Potential Sources (Commercial and/or Industrial) Automotive Factories Cement Factories Chemical Processes of Hydrocarbons Construction/Demolition Laundromat Dry goods Factory Repair and Manufacture of Electrical Products and Electronics Bus and Taxi Terminal Processing of Foods Funeral Services and Cemeteries Repair and Manufacture of Furniture Gas Station Hardware Store and Lumber yard Deposits of Trash Manufacture of house products Deposits of scrap iron Laboratories Centers of repair of machines Centers Doctors and veterinarians Metallurgical factories Military Bases Mining/extraction of sand and gravel Office buildings Photograph development Petroleum Residue Manufacture of plastic and synthetic products Centers of sale Tanks of underground storage Treatment of wood Processing of wood Potential Sources (Municipal and/or Residential) Airports Centers of treatment of potable water Parks Houses Latrines Colleges Highways Stations of public services Centers of treatment of water grays/blacks Potential Sources (Agricultural and/or Rural) Handling of animals Agriculture Liquid lagoons and remainders Handling of forests Storage of fertilizers, Pesticides, and petroleum Type of Contaminant Acids, Antifreeze, Metals, Petroleum Residue, and Solvents Acids, Metals, and Solvents Acids, Metals, Petroleum Residue, and Solvents Acids, Dusts, Metals, Sediments, and Solvents Solvents Acids, Metals, Solvents, and PCBs Acids, Metals, Solvents, PCBs, and Dusts Acids, Antifreeze, Metals, Petroleum Residue, and Solvents Acids, Metals, and Solvents Nutrients, Pesticides, and Solvents Metals and Solvents Antifreeze, Metals, Petroleum Residue, and Solvents Acids, Metals, and Solvents Metals, Pesticides, and Solvents Acids, Metals, Sediments, and Solvents Acids, Metals, and Solvents Acids, Metals, Petroleum Residue, and Solvents Acids, Antifreeze, Metals, Petroleum Residue, and Solvents Acids, Antifreeze, Metals, Petroleum Residue, and Solvents Acids, Antifreeze, Metals, PCBs, and Solvents Metals, Pesticides, Petroleum Residue, Radioactive Remainders, and Solvents Metals, Sediments, and Solvents Acids, Antifreeze, Metals, Petroleum Residue, and Solvents Acids, Antifreeze, Dusts, Metals, Wastes, and Solvents Acids, Antifreeze, Smoke, Metals, Petroleum Residue, and Solvents Acids, Metals, and Solvents Metals, Petroleum Residue, and Solvents Creosote, Metals, and Solvents Acids, Antifreeze, Metals, Petroleum Residue, and Solvents Type of Contaminant Acids, Antifreeze, Metals, Petroleum Residue, and Solvents Acids, Metals, PCBs, and Solvents Nutrients, Pesticides, and Sediments Bacteria, Nutrients, Pesticides, Petroleum Residue, Sediments, and Viruses Bacteria, Nutrients, and Viruses Creosote, Metals, Pesticides, and Solvents Petroleum Residue and Sediments Acids, Creosote, Metals, and Solvents Bacteria, Nutrients, Metals, Solvents, and Viruses Type of Contaminant Acids, Bacteria, Microbes, Solvents and Viruses Acids, Metals, Nutrients, Pesticides, and Sediments Bacteria, Microbes, Nutrients, Solvents, and Viruses Nutrients, Pesticides, and Sediments Nutrients, Pesticides, and Petroleum Residue such as was done in Esteli by the students at National Autonomous University of Nicaragua (Universidad Nacional Autonoma de Nicaragua)/University Center of the Northern Region (Centre Universitario de la Region Norte). Experience shows that certain potential contaminants are often associated with specific activities, land uses, or industries. For example, bacteria in drinking water are generally associated with cattle or human waste, and pesticides are generally associated with agricultural practices. A list of potential sources of contami- nation in Nicaraguan communities and the associated contam- inants is provided in Figure 4.12 developed by the UNAN/CURN students. There are four main steps involved in identifying potential sources of contamination. At a minimum, Step 1 should be completed. Information collected in Step 1 can be supple- mented by completing Steps 2 and 3. Step 4, mapping, is a very important tool to help decision-makers interpret the infor- mation collected in previous steps. 1. Review the public records To begin the process of identifying potential sources of con- tamination, a search of available public records should be con- ducted. Municipal or other government-issued maps may show the location of potential sources of contamination like gas stations, automobile repair shops, factories, or wastewater outfalls. Land-use maps can identify areas where non-point sources of contamination such as agricultural runoff and stormwater runoff from roads may be of concern. If available, tax records, land use or property maps, and other government records can be useful in identifying potential sources of con- tamination. One of the best resources to help identify potential sources of contamination will be local environmental and water supply officials and agencies. Fire departments, planning officers, health departments and public works departments may have information. The local agency managing the water system may already be aware of activities within the area that threaten the water supply, and may have records of contaminant sources. Students at a nearby university may also be of assis- tance in identifying and locating contaminants and sources of concern. Point Sources and Non-Point Sources of Contamination Some potential contaminant sources are easier to map than others, because they are located at dis- tinct points, while other sources, such as agricul- tural runoff, occur over a larger area. These two different types of contaminants are referred to as point sources and non-point sources, respective- ly. Point sources of contamination have a single identifiable location, such as an outfall pipe from a sewage treatment plant. This type of contami- nation is often easier to monitor, control, and regulate than non-point source pollution. Non- point sources of contamination do not have a sin- gle point of origin. Instead, they are diffuse, and include the following: • Fields, which contribute agricultural runoff that may contain agrochemicals (pesticides and fertilizers) and/or bacteria from live- stock; • Roads, which contribute runoff that may con- tain metals and oils from vehicles; and • Communities of roofs, which as a whole act as a diffuse source and which can contribute bacterial and inorganic pollutants to surface runoff and infiltrating water during rain events. The nature of non-point sources makes them more difficult to control and regulate. However, they are often responsible for the largest amount of contamination in source waters. Figure 4.12 Figure 4.13 2. Interview people who know about the area The people who live and work within the source water protection area can provide very valuable information that may not be found in the public records. Shop owners can provide a wealth of infor- mation on the materials and practices they employ. Local inhabitants often make observations that can add to the knowledge of possible contaminant sources in the area. These people may know where a certain outflow pipe is located, or they may be ------- Inventories of Potential Contaminant Sources for Four Wells in Esteli Wells Number 9 and Number 19 (Combined Potential Sources (Commercial and/or Industrial) Residual water Mill Bread store Illegal Waste Processing of wood Mechanics shop Hair salon Potential Source (Municipal and/or Residential) Latrines Residual Water Colleges Potential Source (Agricultural and/or Rural) Handling of animals Inventory) Number of Facilities 4 2 5 1 2 2 3 Present? (amount) For all of the population 3 1 Present? (amount) 2 Types of Contamination Soap, detergent, bacteria, virus, and nutrient Soap and Detergent Detergent and Soap Solid Waste Acids, gasoline, glue, antifreeze, solvents and metals Acids, antifreeze, solvents, metals and gasoline Dyes, oxygenated water, permanent, soap, shampoo Types of Contaminants Bacteria, virus Soap, detergents and chlorine Metals, pesticides and solvents Types of Contaminants Bacteria, virus and organic waste Well Number 14 Potential Source (Commercial and/or Industrial) Carpentry factory Saw mill Bus Terminal Illegal waste Mill Tobaco factory Photographic studio Coffee packaging factory Mechanic shop Brick floor factory, Laundamat, latrines and tubes Wooden box factory Potential Source (Municipal and/or Residential) Latrines Causes Houses College Potential Source (Agricultural and/or Rural) Handling of animals Present? (amount) 2 3 1 3 4 5 1 1 5 1 1 Present? (amount) For all of the population 5 All the district 3 Present? (amount) 2 Types of Contaminants Soap, solvent and varnish Metals and solid waste Metals and oils Solid waste Soap and detergent Fats, solid waste Solid waste Solid waste and oils Gasoline, oil, fat and solid waste Disolvent, oil, dyes, cement, metals Fat. Solvent, sellador, glue Types of Contaminants Bacteria, virus Bacteria, sediments and solid waste Bacteria, virus, garbage Detergents, chlorine and soap Types of Contaminants Bacteria, virus and organic waste Well Number 8 Potential Source (Commercial and/or Industrial) Brick factory Mill Bread store Illegal waste Furniture factory Mechanics shop Washing of cars Hair salon Potential Source (Municipal and/or Residential) Latrines Residual Water Houses College Potential Source (Agricultural and/or Rural) Handling of animals Present? (amount) 2 4 1 3 9 4 1 1 Present? (amount) For all of the population 2 All the district 5 Present? (amount) 2 Types of Contaminants Organic Material Soap and Detergent Oil Solid Waste and Metals Acids, gasoline, glue, antifreeze, solvents and metals Gasoline Lubricants. Oil, paint Oxygenated Water Types of Contaminants Bacteria, virus Soaps, detergents and chlorine Bacterias, solid waste Chlorine and detergent Types of Contaminants Bacteria, virus and organic waste aware of a certain business's disposal practices or past prac- tices. Local officials are another excellent source of input on public contamination sources. 3. Walk/tour the source water protection area Perhaps the most useful method to collect information on public contamination sources is by walking or touring the source water protection area and visiting the locations iden- tified as having potential sources of contamination. Talking with the owners/operators, observing their operations, and reading product labels can be very revealing. Foot surveys will also provide verification of contaminant source loca- tions and may unveil additional potential contaminant sources. Students in Esteli collected potential contaminant source inventories for the 16 candidate source water protection areas in their town by walking through the protection areas they had delineated. To compile detailed inventories, they spoke with local business owners, observed local practices, and noted the type and number of potential sources and associated contaminants. Figure 14 presents a sample of Watershed Area Boundary ..rXM V- Common Clothes Washing Location Source Water Protection Area y^Watershed ' Boundary Public , Drinking Water Intake e Well Furniture Factory Students in Esteli touring the source water protection area. four of the inventories from Esteli. The students decided to combine the inventories for Wells 9 and 19 because the protection areas overlapped almost entirely. 4. Map the contaminant sources Once the potential sources of contaminants in the source water protection area are identified, the final step is to map their location on a source water protection map. An example of a mapped source water protection area in which the potential contaminant sources have been identi- fied is shown in Figure 4.15. The mapped areas should show the public supply well location(s) or drinking water intake locations as well as the potential contaminant sources. Figure 4.15 Simple example of a source water protection area in which the potential contaminant sources have been mapped. Source Water Protection Area for a Well Not to Scale Figure 4.14 Protection of source water requires a collaborative community approach. It is therefore critically impor- tant to maintain good relationships with all stakeholders even in cases where they may be responsible for release of potential contaminants. This objective should be kept in mind while touring a source water protection area. The process of performing the contaminant source inventory may be a good opportunity to begin a dialogue, with people living and working in the protection area, about source water protection and the connections between health and drinking water protection. Chapter 9 provides more ideas about where to find additional information on the drinking water supply and potential contaminant sources in your town. 7 ------- 4.5 Ranking of Potential Contamination Sources After all of the major potential sources of contami- nation have been identified and mapped, ranking of those sources will help to guide the management strategy developed by a community or its represen- tatives. Financial resources available for source water management are commonly limited. Therefore, every effort should be made to direct management efforts to the most important locations and the most harmful contaminant sources. Ranking the threats from each potential source of contamina- tion based on the magnitude of the threat, allows for development of an efficient management strategy. protect drinking water sources from contamination. The basis for ranking contaminants is the decision of and overseen by the Source Water Management And Planning Committee (see Chapter 5). It is useful to develop a simple matrix to compare the threats of public contaminant sources. Some may be more harmful to human health than others. Some may be easier to control and/or cheaper to manage than oth- ers. Some may be reaching the water supply in greater concentrations than others. Proximity of the contamination source to the water resource, the type of contaminant, the quantities of hazardous materi- als on a property, travel times and natural degrada- tion of chemicals, and management practices of the owner/operators are also important considerations. Figure 4.16 shows an example of a basic ranking Representative Values for Nitrogen Loading Rates for Various Sources matrix that might be developed by a community in Ranking Matrix of Potential Sources and Contaminants Source Bus Terminal Gas Station Open Defecation Cattle grazing Furniture Factory Contaminants Oil and grease Oil and grease Bacteria Bacteria Solvents, oil and grease Proximity to Well" 4 4 4 2 2 Travel Time to Well" 4 4 3 2 3 Quantity of Contaminant1 5 5 5 5 2 Natural Degradation" 4 4 2 2 4 Total Rank (Average) 4.25 4.25 3.5 2.75 2.75 a) 1 = far, 5 = close b) 1 = long time, 5 = long time c) 1 = small, 5 = large d) 1 = very rapid, 5 = slow Figure 4.16 Ranking of potential sources of drinking water con- tamination can be performed, as is done in the United States, for example, by the entity responsible for delivering water, or by the local health or sanita- tion board. Ranking can also be done by a commit- tee or by a group that represents the various stake- holders in the protection area. The ranking of con- tamination sources provides an important piece of information for the source water managers and stakeholders. It is from this ranking that members of the public are able to contribute informed input on planning protection activities. Source water man- agers can look at a list of priority sources of con- tamination and decide upon appropriate actions to Nicaragua. One fundamental consideration in ranking potential contaminant sources is the relative amount (or "load") of pollutant, which might be generated by each source within the watershed. For example, one source might be cattle (a non-point source of con- tamination). If cattle have free access to a river that serves as a water supply, the potential nitrogen load from those cattle could be estimated. If it is known that there are 80 head of cattle grazing in the source water area within close or direct proximity to the river, and each head of cattle generates approximate- ly 73 kg of nitrogen per year in manure (Lander, et al., 1998), the loading of nitrogen can be estimated at 5,840 kg/yr from the cattle. Land Use Loading Rate Atmospheric Deposition on Forest Landa Atmospheric Deposition on Agricultural/rural Landa Atmospheric Deposition on Urban Industrial Landa Latrinea Cattle" Horseb Agriculture3 Pasture* 6.4 kilograms/hectare/yr 13.3 kilograms/hectare/yr 21.2 kilograms/hectare/yr 2.5 kilograms/person/yr 73 kilograms/animal/yr 54 kilograms/horse/yr 4.9 - 8.9 kilograms/hectare/yr 14.6 kilograms/hectare/yr a) Source: EPA. 1999. Tools for Watershed Protection: A Workshop for Local Governments. Prepared by Inc. for US EPA, Office of Wetlands, Oceans and Watersheds. b) Source: MA DEP No Date. Massachusetts Department of Environmental Protection. Nitrogen Modelin Horsley & Witten, Inc. for the MA DEP, Division of Water Supply. Horsley & Witten, g. Prepared by Figure 4.17 Based on that estimate, the cattle farm could be ranked in a matrix against other sources in terms of importance and potential impact to the water supply. A cattle farm with cattle roaming in the river would likely be given a high rating, perhaps a 5 on a scale of 1 to 5 (5 being of greatest concern), since it has the potential for major negative impacts to water quality. However, if the same number of cattle are restrained from access to the river, and direct flush- ing of cattle urine and feces into the river are miti- gated, that source of contamination would likely receive a lower rating, perhaps a 2 or 3, as it does not pose as great a threat to water quality. Similar meth- ods can be used for other potential non-point pollu- tant sources, such as pesticide use on agricultural lands or fecal bacteria from humans and cattle in the source water protection area. A point source of contamination like a sewage out- fall pipe might receive a rating of 5 if the discharge were close enough to a water source as to pose a serious threat to water quality. However, it might receive a 3 if the sewage is treated before being released and if it is located on the outer perimeter of the area of contribution to a water source. Contamination sources that might receive a ranking of 1 or 2 would be perhaps a hair salon that utilizes small quantities of hazardous materials, a small chemical user that complies with waste disposal guidelines or regulations set by the environment ministry, or a coffee farm, if it were organic and treated its coffee processing waste. 4.6 Conclusion Source water assessment includes all the steps out- lined in this chapter: delineation of the SWPA, inventory of potential contaminant sources, and ranking of those sources. These steps lay the foun- dation for the development of a management plan to protect the source water area. Stakeholders can then play a vital role in determining what actions might be most effective to protect and manage the drinking water sources. A guide to developing a management plan is presented in Chapter 5. The key to success of a source water management plan is to provide a mechanism for the general public to participate in the development and implementation of the manage- ment plan. A primer on public participation in source water management is provided in Chapter 6. The next step in source water protection is to devel- op a program to include the public in shaping a com- munity source water protection plan. ------- 5 Developing a Community Source Water Management Plan 5.1 Introduction 5.2 A Review of the Existing Legal Framework for Source Water Protection and Management in Nicaragua 5.3 Assessing the Current State of Drinking Water Management in a Community 5.4 Developing a Consensus-Based Source Water Management Plan 5.5 Water Supply Treatment in Conjunction with Source Water Protection 5.6 Local Management of Water Supplies 5.1 Introduction Once the Source Water Assessment (Chapter 4) has been completed, a management plan can be devel- oped to protect the community's drinking water sources. This chapter describes activities that are essential in establishing an effective source water management plan, including: • assessment of the current management of local drinking water; • development of a consensus-based management plan; • identification and selection of a set of manage- ment tools to help carry out the source water management program; • coordination of source water protection with centralized treatment, and Before developing a source water management plan, it is important to understand the legal basis for watershed protection and drinking water protection that already exists in Nicaragua. 5.2 A Review of the Existing Legal Framework for Source Water Protection and Management in Nicaragua Several laws have been enacted in Nicaragua that provide a legal basis for drinking water protection and environmental protection. Law 290, the Law of Organization, Competencies and Procedures of the Executive Power, (Ley de Organization, exploration of local management options. How many people receive waterfront the local public water supply? Competencias y Procedimientos del Poder Ejecutivo, 1998), outlines the responsibilities, including those pertaining to environmental protec- tion, of all national government agencies. In accor- dance with this law, several national agencies are accountable for various aspects of environmental protection, environmental monitoring and natural resource use (Ministry of Environment and Natural Resources [Ministerio de Ambiente y Recursos Naturales], no date). This law establishes MARENA's responsibility for protecting the environment through formulating and managing national policy, setting environmental quality standards, overseeing compliance with those standards, administering a system of environmental impact assessment, and controlling activities that may contaminate the environment (MARENA, no date). The Ministry of Agriculture and Forestry (Ministerio de Agricultura y Forestal) is responsible for administering policies for agricultural and forestry development in Nicaragua. MAGFOR also must coordinate with MARENA to develop propos- als for ecological protection programs, "with empha- sis on the conservation of soils and water (MARE- NA, no date)." The Nicaraguan Aqueduct and Sewer Company (Empresa Nicaraguense de Acueductos y Alcantarillados) is responsible for providing potable drinking water and sanitation services nationally. It has a division called the Rural Areas Division of the Nicaraguan Aqueduct and Sewer Company (Empresa Nicaraguense de Acueductos y Alcantarillados - Division de Areas Rurales) that is responsible for rural areas. The Ministry of Health (Ministerio de Salud) promotes environmental health and good hygiene among the population, formulates standards for hygiene and environmental health, and controls the quality of water for human consumption. The law most directly pertaining to drinking water protection is Law 217, the General Law of the Environment and Natural Resources (Ley General del Medio Ambiente y los Recursos Naturales) (pub- lished in the Diario Oficial in 1996). This law estab- lished MARENA's responsibility for regulating and What major problems exist with regard to the public drinking water supply? What are the trends in popu- lation and land use? Who manages the local drinking water supply? What organizations are already in the community and are concerned with drinking water? What other entities are organized and active in drinking water protection? ------- setting national environmental standards. Title III outlines MARENA's responsibility to carry out envi- ronmental laws and uphold natural resource use standards. Title IV addresses environmental laws and standards for environmental quality and the con- trol of contamination of air, water and soil. Another law, the Disposiciones Para el Control de la Contamination Proveniente de las Descargas de Aguas Residuales Domesticas, Industriales, y Agropecuarias, Decree Number 33-95, was passed in 1995 in an effort to control contamination of water from various discharge sources in Nicaragua. This law sets maximum limits on various contami- nant concentrations in the discharge of different cat- egories of household, industrial and agricultural wastes into sewer systems and surface waters. Implementation of Decree Number 33-95 falls under the jurisdiction of MARENA. Municipalities also share in the responsibility for environmental health and drinking water protection as outlined in the Ley de Municipios (Ley 40 and 261) (MARENA, no date). They are responsible for rational use and conservation of natural resources, developing local initiatives for environmental pro- tection, and contributing to national efforts to moni- tor and control environmental quality. Municipal officials, local representatives from MAGFOR, MINSA, and MARENA, and local leaders from NGO's meet in Ocotal, Nicaragua to discuss the local source water protec- tion project. Together, these laws provide legal environmental framework to support development and implementa- tion of a national program or network of programs for source water protection in Nicaragua. Because the number of government entities tasked with pro- tecting, monitoring and using natural resources in Nicaragua is large, coordination is suggested. Designating a lead agency for source water protec- tion is often helpful for organizing discussion and actions toward source water protection, as discussed in later sections of this chapter. 5.3 Assessing the Current State of Drinking Water Management in a Community The development of a source water management plan should begin with an assessment of the current status of local drinking water management and local watershed management programs. It should then build upon the programs and institutions already in place within the community. Therefore, the first step is to examine the existing management structure and identify the organizations involved. The answers to the following questions will facilitate an assessment of the current approach to management of the local drinking water supply: • Who manages the local drinking water supply? Is it a local water utility, such as AYAMAT in Matagalpa, a national water utility, such as ENACAL, or some other entity? • How many people receive water from the local public water supply? Where do they live? Who lives in the source water protection area, and do they all receive water from the public water sup- ply? • Who works or lives in the source water protec- tion area that does not utilize the public water supply? • What existing local, regional, national and inter- national institutions and organizations are con- cerned with drinking water, public health and/or environmental resources and are active in the community? • What other entities in the community are organ- ized and active and could become involved in drinking water protection? • What are the trends in population and land use within the source water protection area? • What major quality and quantity problems exist with regard to the public drinking water supply? • What problems can be expected in the future? In researching the answers to these questions, it will be necessary to talk to the mayor's office, the health department, MINSA, the ENACAL office, and vari- ous other agencies, individuals, and organizations in the community. The goal of this step is to under- stand the current management arrangements so that a new effort to protect source waters can build upon the system that already exists. This assessment will also help determine where there may be strengths and weaknesses in the current management struc- ture, which will help direct development of the man- agement plan. 5.4 Developing a Consensus-Based Source Water Management Plan Once the current state of drinking water management is documented, efforts to develop a management plan for drinking water sources can be initiated. One key to developing and implementing a successful drinking water source management plan is involvement of the local government. The Mayor's office should be involved in the development of the plan, and the Mayor should be briefed on the source water protec- tion issues. The involvement of municipal depart- ments is also recommended, for example the Planning Department (where zoning may be administered) and the Health Department (where water quality monitor- ing may be coordinated). Another key to a successful source water management plan is involvement of stakeholders and community members. Both of these groups should be permitted and encouraged to participate in the development of the management plan. These groups include people who not only drink the water and benefit from a clean source of water, but can also affect the quality, and even the quantity of the water supply. Management plans depend to a significant degree on public and stakeholder support and participation. Without the input and support of both stakeholders and communi- ty members, a management plan may overlook or incorrectly address important issues, and may there- fore be extremely difficult to put into practice. There are several steps that should be followed in developing a community-based source water manage- ment plan. These efforts build on the information that has already been collected in the Source Water Assessment (Chapter 4), the public participation phas- es of the program (Chapter 6), and the assessment of current source water management (described above). Steps to a Source Water Management Plan 1. Initiate the Source Water Protection Process 2. Form the Source Water Management Planning Committee 3. Define Collective Management Goals 4. Define the Time Frame of Your Management Goals 5. Develop a List of Management Options to Achieve the Management Goals 6. Determine the Primary Implementing Body for the Plan 7. Choose Management Tools and Develop a Detailed Management Plan 8. Review and Update Management Plan Figure 5.1 ------- 5.4.A. Initiate the Source Water Protection Process. Developing a source water management plan is most likely a combined effort among the local, regional, and national governments, stake- holders such as industries and NGO's, and commu- nity residents. From experience with the pilot proj- ects in Esteli, Matagalpa and Ocotal, it is clear that clean drinking water is a prime concern among peo- ple in the communities. The idea of a long-term pro- gram to manage and protect drinking water sources has met with positive responses in these pilot project towns. Such a program, however, requires leader- ship to initiate it and strong management to carry it out. At the local level, a source water protection program can be initiated by the entity that has legal authority to do so, which may be the office of the Mayor. Leadership for the program can come from munici- pal and/or quasi-municipal departments with person- nel that understand the circumstances surrounding source water management within their specific com- munity, including general land uses, social and health concerns, and economic issues. As discussed in Section 5.3, the local source water protection effort should build off of the existing institutional structure within each city. The institu- tional structure of each city can vary, and each may be slightly different. 'Institutional structure' refers to the variety of agencies that play a role in day-to- day city management. Examples may include: • departments within the Alcaldia; • educational institutions present in the city; • non-governmental organizations functioning in the town; • multilateral and bilateral aid projects established in the town; • health centers; and • the drinking water management agency. 5.4.B Form the Source Water Management Planning Committee. A fundamental component of a source water protection program is establish- ment of a committee to write a source water protec- tion plan and assist in its implementation. The enti- ty with the legal authority to initiate source water protection in the community should draw on local human resources to form a committee on source water management. The committee can then be charged with the responsibility to develop the plan. There are several options for the composition of this Source Water Management Planning Committee. It can be made up of stakeholders, health profession- als, water utility managers, or some combination of these groups. This committee should, with oversight from either the local government or the local water utility, take the lead in development of a local source water management plan. Part of the Source Water Management Planning Committee's role should be to organize a forum, such as a series of public meet- ings, for public participation and input in the devel- opment of the management plan (see Chapter 6: Public Participation). The local government, with the support of the committee, can also work with other local governments, and the national govern- ment (probably ENACAL in the case of Nicaragua) to develop the appropriate structure for a national source water protection program. Who are 'Stakeholders'? Any specific interest group, company, or organization that is affected by water quality, affects water quality, or may be affected by the management of a source water protection area falls into the stakeholder category. This list will likely be quite long for any given protec- tion area. For example, local associations of cattle ranchers or coffee growers as well as stu- dent environmental awareness groups might all share a specific interest in the quality and man- agement of the drinking water source, and should all be considered stakeholders. Just as the general community's input is integral to the success of the management plan, so is the input of all stakeholder groups in a source water pro- tection area. Figure 5.2 Initiation of Source Water Protection in Ocotal At the initiation of the Ocotal pilot project, repre- sentatives from the Mayor's office brought togeth- er a group of stakeholders to discuss source water issues. This group could become the basis for a source water management planning committee. The participants at the meeting included a wide variety of non-governmental and governmental organizations involved in drinking water and health issues in Ocotal. The attendees represented the following organizations: Movimiento Comunal (Community Movement) Association of Women in Development (AMDES) INAFOR MARENA MAGFOR World Relief/ Auxilio Mundial MINSA High School of Biologists and Ecologists of Nicaragua (COBEN) - Ocotal Office of the Mayor (Alcaldia) 5.4.C Define collective management goals. An effective source water management plan must have a clearly-stated set of goals. Different stakeholders or stakeholder groups may prefer different management goals. Members of the public may also other view- points. It is critical that the process of establishing goals be done in a manner that builds consensus. In some localities, the management goals may be quite clear, but in most cases, this step can be expected to require significant discussion. Management goals should be defined in measurable terms. Clear goals provide strong guidance for developing management options, and allow accurate assessment of the effec- tiveness of the management plan over time. All interested stakeholders and members of the public should have input into defining the source water man- agement goals, and every effort should be made to get as many affected people involved in the decision-mak- ing as possible. A recommended forum for discussion is a well-publicized, open public meeting. The broad- er the involvement of stakeholders and the public in this process, the more likely the plan is to succeed. ------- A meeting of stakeholders in a small source water protection area in northern Nicaragua may have an invitee list as follows: ENACAL Any interested citizens ENACAL-DAR Alcaldes from all towns involved Coffee growers association MINSA University Students studying Environmental Management High School Environmental Awareness Group Cattle farmers association MAGFOR Rice producers association Local Businesses: • Local gas station manager Furniture Finishing Factory Owner/Manager MARENA Figure 5.3 Water treatment plant operator The substance of the management goals should be driven primarily by the source water assessment for the protection area (Chapter 4) and by the input of stakeholders and the public. It is important that stakeholders and the public are made aware of the assessment information so that they have all the nec- essary information to engage in an informed discus- sion. A management goal may be based on achiev- ing better water quality, for example, reducing fecal coliform bacteria to a certain level at the drinking water intake or reducing the concentration of nitrate to a specified level. Alternately, a management goal may be defined using human health parameters, such as a 50% reduction in the incidence of diarrhea in children. Management goals may also address uses of land and water, such as reducing the number of cows roaming in the river by 75 %, or increasing the use of latrines by permanent and seasonal residents in the watershed by 90 %. 5.4.D Define the time frame of the management goals. Another important component of the source water management plan is the time frame in which the goals are to be reached. It is common to have both short-term and long-term management goals. Using examples from Section C above, a short term management goal may be a documented increase in the use of latrines; a medium term goal could be a numerical reduction in the number of cows with free access to rivers; and a long term management goal may be a measured improvement in water quality. An example timetable is shown in Figure 5.4. 5.4.E Develop a list of local management options to achieve the management goals. While energy, interest and support from the commu- nity and stakeholders is essential to a program's suc- cess, management of a source water protection pro- gram is generally a joint venture between the nation- al and local government. On the national level, the agency in charge of drinking water management, for example, ENACAL, would be the most likely and logical agency to oversee the program. Collaboration with the Ministry of Health is neces- sary to appropriately address the human health risks from the drinking water contaminants of concern. The national government will also benefit from local collaboration in the local assessment and implemen- tation of a national source water protection program. However, a national framework for source water protection would provide additional needed finan- cial, legal, technical and organizational support from the national government. Municipalities can use their local regulatory author- ity to promote source water protection by employing one or a combination of tools, such as: • Incorporate watershed management costs into the local water rates to cover some costs associated with the source water protection program. Local water management agencies, such as AYAMAT in Matagalpa, or the local offices of ENACAL could include a very small fee within the water rates specifically for watershed management efforts, such as public education or construction of community wash stations. • Develop zoning regulations for specified land uses within source water protection areas. For example, in a town that depends primarily on ground water, such as Esteli, it may be helpful to develop a zoning map based on the source water protection areas for the wells that would exclude certain risky commercial and industrial land uses from those areas. • Develop a framework for conservation ease- ments to conserve natural lands in protection areas. For example, a local non-profit organiza- tion may be interested in conserving some natu- ral land for ecotourism, environmental health and/or source water protection. By providing a framework for easements to be instituted, the likelihood of the land actually being protected is increased. • Provide tax incentives (and reduce disincentives) for improvements in land use, household and industrial practices and the use of innovative and alternative technologies that reduce source water contamination. For example, there is currently an improvement tax levied on coffee farmers that build coffee husk collection basins. These basins allow coffee farmers to ferment the husks into fertilizer rather than disposing of them directly into surface waters. Conversely, a tax break would actually provide more incentive for coffee farmers to invest in these basins. These tools and others are described in more detail below. In general, management tools fall into one of two categories: regulatory and non-regulatory. Example Management Goals and Target Dates for a Source Water Management Plan Management Goal Increase use of latrines to 90% of population Reduce fecal coliform counts at drinking water Intake by 75% Reduce annual Incidence of diarrhea In children by 50% Reduce the number of cows grazing directly in the river by 75% Target Date 1 -3 years 3-5 years 3-5 years 3-5 years Figure 5.4 ------- Regulatory Tools: Regulatory tools may include zoning, health regula- tions, performance standards and best management practices. These may not currently exist, but are worthy of consideration. Zoning Regulations. The purpose of zoning is to separate incompatible land uses by assigning dif- ferent areas for each use (e.g., commercial, resi- dential, industrial, agricultural) and setting stan- dards for the uses permitted in each zone. A zoning board of the local municipal government usually determines zoning regulation. Under the umbrella of zoning regulation, the type of land uses, the density of land uses, and the allowable practices for each land use type can be regulated. For example, a zoning map could be used to reg- ulate agricultural practices in a given area such that pesticide use in that area may not exceed a prescribed level. Similarly, certain types of industry that pose high risks to water quality may be prohibited in identified source water pro- tection areas around drinking water wells. Health Regulations. A health regulation can be adopted by a municipality to protect drinking water. Health regulations can include prohibi- tion of dwellings and latrines within a buffer area around a well or surface water intake or prohibi- tion and control of the use of certain pesticides in a delineated source water protection area for a drinking water intake or a well. • Performance Standards. A local health or water board may impose a requirement that any water discharges to the ground or to a surface water body must meet certain water quality limits. For example, a surface water discharge may be required to have undetectable levels of bacterial contamination, low nutrient concentrations or limited levels of metals and organic chemicals. • Best Management Practices. A community reg- ulatory authority could require residents and businesses to employ certain techniques called best management practices (BMPs), to minimize the discharge of pollutants into drinking water sources. Examples of BMPs might include fenc- ing of livestock away from surface waters, regu- lar removal of solids in latrines, and the use of infiltration basins to minimize contaminant load- ing to surface waters from storm water runoff. • Tax Breaks. Tax breaks from the local or nation- al government may help to promote positive source water protection improvements and actions among individuals and companies. For example, tax breaks could be awarded for improvements such as pretreatment of discharge water from industry or improved on-site land use management, or for a contribution to a public education campaign. Non-Regulatory Tools: Non-regulatory management tools can be very effec- tive in protecting drinking water by providing infor- mation and opportunities for involvement. • Education. Public education campaigns can be carried out by many different groups in a com- munity, depending on the interest and resources of those groups. Educational efforts are often an effective way to spread the word about issues, especially in cases where general awareness is low. For example, as part of the Ocotal pilot project, students in a local environmental brigade carried out an educational campaign to teach coffee workers, cof- fee farm owners, and cattle ranchers about the connec- tion between their activi- ties, various land uses, the quality of the water they drink, and their personal health. The use of conservation easements for ecologi- cal and natural resource conservation in Latin America is a relatively new and exciting prac- tice. The first Latin American conservation easement (servidumbre ecologica) was instated in 1992 in San Ramon de Tres Rios, near San Jose, Costa Rica after the idea was introduced to Central America by the Iniciativa para la Conservation de Tierras Privadas de Centre America (Mack, 1997). Since then, over 35 con- servation easements have been negotiated throughout Central America and Mexico (Charney, 2000). Conservation easements can protect vital source water areas. In some cases, a conservation ease- ment can open a natural area to use by the pub- lic for low-impact activities such as hiking while still maintaining ecosystem integrity. Easements can be a useful tool for protecting undeveloped Conservation Easements. Conservation easements are land use rights that are turned over from a private landowner to a town, national government, indi- vidual or conservation group in exchange for some financial reward, usually in the form of a tax break. The owner of the land retains title to the property, but gives up the right to develop that land. s ] ource Water Management Tools and Possible Implementing Agencies Management Tools Possible Implementing Agency Regulatory • Zoning Regulation • Health Regulation • Performance Standards • Best Management Practicies • Tax Breaks Zoning Board, Office of the Mayor MINSA, Office of the Mayor MINSA, ENACAL, MARENA Office of the Mayor, MARENA, MAGFOR Office of the Mayor, ENACAL, National Government Non-Regulatory • Education • Conservation Easement • Water Quality Monitorings • Local Drinking Water Management • Economic Incentives Office of the Mayor, School Group, ENECAL, MINSA, Non-Governmental Organization Office of the Mayor School Group, ENECAL, MINSA, Non-Governmental Organization, MARENA ENACAL, Office of the Mayor National Government, Municipal Government "igure 5.5 ------- areas within a source water protection area around a well. However, the benefits to the landowner must be significant and there must be enough confidence in legal land rights structures to ensure that the easement will be upheld in per- petuity. Water Quality Monitoring. Monitoring the qual- ity of source water is a very useful and important management tool. Monitoring allows a commu- nity to identify water quality issues and track the successes and failures over a period of months or years. It also enables a community to identify water quality problems as they arise. An impor- tant part of source water protection is monitoring the quality of the water supply at different points in the delineated source water protection area. Ongoing water quality monitoring allows the community to recognize threats to drinking water and identify contaminant sources. It allows rapid identification of contaminants and enables timely response. Monitoring programs can be expensive, but a collaborative approach that utilizes local funds, volunteer aid, and national support can make a comprehensive monitoring effort economically feasible. Water quality data can be useful not only to a specific source water protection program, but also for universities, environmental and other non-governmental organizations, health offi- cials, and local or national government entities interested in further study of water quality relat- ed issues. Water quality monitoring can be car- ried out by a national agency, such as MINSA or ENACAL, by the local municipal government, or by local citizen groups, which can be extreme- ly effective. While laboratory services are not accessible to most communities in Nicaragua at the present time, affordable water quality moni- toring kits are available from several companies. These test kits generally allow field-testing of pH, temperature, nitrates, fecal or total coliform bacteria, and some metals. Therefore, the water quality results can be obtained rapidly in the Monitoring the quality of source water is a very useful and important management tool Figure 5.6 field rather than requiring water quality tests to be performed in a laboratory. Laboratory water quality testing on a routine basis may be expen- sive and/or logistically difficult due to travel between the sample location and the laboratory. When taking water quality samples, it is impor- tant to properly document the sampling process and sampling conditions for future reference. An example of a basic water quality sampling field data sheet that could be used for documen- tation is presented in this chapter. • Local Drinking Water Management. Another non-regulatory tool is the establishment of a local water control or authority (for example, AYAMAT in Matagalpa) (see Figure 5.7). Local control of the water source and water treatment and distribution system can be beneficial to the community because a local board may be able to react to local needs more directly and rapidly than a national agency. • Economic Incentives. A final tool that can be considered under the non-regulatory framework is the development of economic incentives to encourage landowners and businesses to take Water Quality Sampling Field Data Sheet Stream (Well) Name/Number: Watershed Name: Municipality: Department: Geographic Location: Sampling Site Name and Number (if any): Physical Description: Investigators: Date: Time: Weather in the Past 24 hours: (storm, rain, showers, overcast, clear/sunny) Current Weather: (storm, rain, showers, overcast, clear/sunny) Comments: Sampling information: Sample Number Parameter Field Measurement action to protect water quality. This may be in the form of a government grant or favorable financing for loans to make improvements that help to protect source water. Examples of posi- tive improvements include a settling basin for recovering coffee husks, construction of a biodi- gestion chamber for coffee processing discharge water treatment, or construction of a community clothes washing station. Government grants could also support public education campaigns on local source water protection. 5.4.F Determine the primary implementing body for the plan. In order to implement the manage- ment plan effectively, there must be a managing body to oversee the effort. This agency would take the lead on actions contained in the management plan. It would also coordinate with other agencies and organizations to implement each management tool and monitor success. Depending on the tool, coordination would take place between the lead agency and another government body, such as MINSA, MARENA, MAGFOR, ENACAL, the Alcaldia, or a local water board, or a local organiza- tion, such as a school, a non-governmental organiza- tion, or a local association. In some cases, a new group could be formed for the purpose of imple- menting one or more of the management tools. Figure 5.5 presents the source water management tools discussed in the previous section and the pos- sible implementing agencies. 5.4.G Choose management tools and develop a detailed management plan. The final step in the management plan process is to assemble all the plan components into one concise document that is made publicly available. The final management plan will likely include a set of management tools to achieve between one and four management goals in a given time frame. The set of tools could be chosen with stakeholder input at a public meeting or hearing in which the benefits and drawbacks of the tools are presented to the public. A variety of criteria could be used to decide on which tool to use to address a given source water problem. Some tools might be more easily implemented than others, some might address the problem faster than others, or some might be less expensive to implement than others. The goals (discussed in Section C) should be very clearly stated at the beginning of the plan. The plan should document stakeholder and public concerns, and identify who is responsible for implementing each management tool in the plan. Before finalizing the management plan, it is generally a good idea to make the final draft available to stakeholders and the public for a comment period. This will provide all stakeholders and the public with the opportunity to review the plan, express any concerns and have those concerns addressed before the plan is finalized. During development of the management plan, there are several important issues that should be kept in mind. Managing a drinking water source is not a stat- ic process, but an anticipatory (and dynamic) task. Because conditions change with time, there should be ------- provisions in the management plan to deal with unpre- dictable shifts in conditions and/or priorities. It is rec- ommended that the following points be addressed in the planning process: • Plan for new water sources in addition to those already in use. A growing community will need to look for alternative sources of water. Identifying potential future drinking water sources allows the community to protect those sources for future use. Protection may involve special zoning or limited land uses in areas around possible future wells, and may help to direct the pattern of development to ensure a safe drinking water supply in the future. • Develop a contingency plan. It is a good idea for the community to have a contingency plan for alternative drinking water sources. Even with a proper management plan, accidents can happen and a primary drinking water source can become contaminated or a water treatment facility can be disrupted. For example, if ground water is the main source of drinking water, having a large stor- age tank filled at all times, which could be used in an emergency, might be appropriate. In other situ- ations, it may be appropriate to close off a con- taminated ground water well and draw drinking water from alternative wells. To the extent possi- ble, a community should have a plan to warn citi- Local Water Agency An example of a local water agency in Nicaragua that appears to be achieving management success is AYA- MAT (Acueductos y Alcantarillados de Matagalpa). AYAMAT is a semi-private spin-off from ENACAL in Matagalpa, established in the 1990s. AYAMAT is man- aged similarly to a private company but also works in cooperation with ENACAL. It has been successful in managing the issue of limited water quantity in the city of Matagalpa. AYAMAT has been working with the local Mayor's office and the local watershed protection project Proyecto Cuencas Matagalpa to carry out better water supply management for the city and surrounding areas. Figure 5.7 zens of a contamination incident, provide an alter- native drinking water source, repair problems in a water treatment facility, remove the source of con- tamination, and treat the contaminated water so that it can be returned to use. 5.4.H Review and Update Management Plan. Ensure flexibility in your management plan. Because the future can rarely be predicted, flexible manage- ment is a critical characteristic of an effective drinking water protection program. Conditions in the commu- nity may change, and the plan that is developed today may not be the best plan three or five years from now. In order to build flexibility into the source water man- agement, the planning committee should continue to meet periodically to monitor the implementation and effectiveness of the management plan, and to update and adjust the plan to address changing conditions and concerns. In addition, the committee should continue to maintain an open dialogue with stakeholders and the general public, most likely through open information- al meetings or newspaper announcements. 5.5 Water Supply Treatment in Conjunction with Source Water Protection The first defense in providing potable water to an entire community is adequate protection of the drink- ing water resource itself. Once a drinking water source is contaminated, especially a ground water source, it can be extremely difficult and costly to clean. Many pollutants, especially some synthetic chemicals, are very persistent and cannot be broken down easily in nature. In many cases, only a relative- ly small amount of pollutant can contaminate a large volume of water. Effective protection can keep treat- ment costs relatively low and provide more people with access to clean water. However, comprehensive protection of drinking water sources is a long-term process, and may not always succeed. In that case, communities must treat their drinking water, as is cur- rently the case throughout Nicaragua. In general, treatment of surface water supplies provid- ed at centralized treatment centers involves filtration, flocculation, and chlorination. The drinking water treatment process is generally effective in the removal of bacterial contamination, sediments, and many con- taminants that adsorb onto sediments, including pesti- cides and other organic compounds. Ground water treatment is usually less extensive because ground water sources are usually less prone to contamination, especially by bacteria. Ground water is naturally fil- tered as it infiltrates through the ground and reaches the aquifer, so it generally has fewer contaminants than surface water. Treatment of ground water often ranges from no treatment to simple disinfection, usu- ally by chlorination. However, typical treatment regimes for surface and ground waters are only mar- ginally effective in the removal of dissolved contami- nants including organic compounds, metals and nutri- ents. Source water protection therefore plays a key role, not only in improving raw water quality for people who obtain their water before it is treated, but also in reduc- ing human exposure to harmful chemicals and con- stituents that are not removed in the treatment process. Many people in rural areas where centralized potable water systems are unavailable drink water taken directly from a stream or river. For these people, source water protection is likely the only line of defense against certain forms of contamination, such as microbes or pesticides, in their drinking water. A management plan can be used to prevent contami- nants, including those that are difficult to treat, from ever reaching the drinking water source in significant concentrations. Bacteria and sediment that can usual- ly be handled by a treatment plant at moderate levels can, in excessive amounts, overload the plant, requir- ing longer treatment time and more intense chlorina- tion. Sometimes a treatment plant is unable to suffi- ciently remove high amounts of contaminants in the intake water. Decreased levels of contamination enter- ing a treatment plant can help to maintain a more dependable contaminant removal process over a longer period of time. Time Frame for Developing a Source Water Management Plan The time frame for development of a community source water protection plan should be approximately one year. A typical schedule is as follows: • initiation of source water management program (one month) • formation of the source water management planning committee (one month) • organization of first public meeting (one month) • compilation of public comments (one month) • development of draft management plan (four months) • public comment on draft plan (one month) • revisions to draft plan (two months) • presentation of final plan (one month) • review and updating of source water management plan (periodically) Figure 5.8 5.6 Local Management of Water Supplies Direct local management of water supplies is not com- mon in Nicaragua. Other countries, including the U.S., have shown that local management can allow for more responsive management, and create the opportu- nity for collaboration among local agencies. For example, a local water agency can work with the municipal planning office, the local tax office and other local offices to adapt health and land use regula- tions and community management plans for better source water protection. A local water agency can underwrite costs by collection of water use fees. Consequently, a local water entity can be run more like a business than a public agency, with efficient opera- tion and maintenance and more dependable service. This capacity can have important implications for the health of a community. ------- Public Participation - A Primer 6.1 Introduction 6.2 Six Components of Successful Public Participation 6.3 Conclusion 6.1 Introduction Protecting the quality of drinking water begins with people. The people who live in the watershed area of a drinking water intake or in a zone of contribu- tion to a well have a very important role to play. The kinds of things they do on a daily basis have a direct effect on the quality of drinking water. The more people understand their role in both protecting and impacting water quality, and the more they partici- pate in taking action to safeguard water quality, the better the management of the water resource, and the better the health of people in the community. Therefore, public participation is the most critical element of a successful source water protection pro- gram. Without a comprehensive, well-planned effort to include the public in development and implementation of a source water management plan, it is unlikely that the program will be successful. Protecting the quality of drinking water begins with people. "Why should I protect the public drinking water source if I don't drink water from that source?" People who live in the watershed area of a pub- lic drinking water intake or zone of contribution of a well but who do not receive treated water delivered from that intake or well might wonder why they should take action to protect the quality of that water. By protecting the greater source water area, which may also include streams, rivers or wells where they get their own water, people also protect their own water quality and their own health. They will also be contributing to the environmental health of the area. Similarly, a business that operates within a source water pro- tection area, but may not use the public water supply, should take action to prevent possible contamination of public drinking water sources for the benefit of their customers and workers who do use public water. Figure 6.1 6.2 Seven Components of Successful Public Participation Public participation is the process by which all interest groups (stakeholders and the general public) in a com- munity are provided the opportunity to make their views known on drinking water issues and protection, and to contribute to designing a drinking water source protection plan. An effort must be made to include the full range of community opinion in discussion of approaches to protection of drinking water sources so that all issues are brought to light and an appropriate and workable source water protection strategy can be devel- oped. Public participation is important to source water protection because it: -Builds networks among key individuals in a community who will implement source water protection measures, -Identifies needs and priorities with respect to source water protection in the community; -Provides education and information to all residents of a community; -Focuses public attention on the issue of source water protection; -Sets up a framework for community support of protective action; -Builds momentum for the program; and -Provides the benefit of input and experience from a broad cross-section of the community. Public participation has many components, all of which should be considered when developing a source water protection plan. These components potentially include direct involvement of stakeholders in the source water management planning committee (see Chapter 5), involvement in general public informational meetings through submission of written and oral comments, and participation in community events such as art contests and demonstration projects. Additional components include development and distribution of educational products that target the public at large, for example fact sheets, posters, radio ads, brochures, and artwork. There are seven main components to a success- ful public participation effort: 1. Public Introduction to Local Source Water Issues A general public meeting can be a very effective way to introduce the issues relating to the local drinking water source, such as existing and poten- tial problems with contamination of source waters and the impacts that contamination may be hav- ing on public health. Assuming that local gov- ernment will take the lead on source water pro- tection and management in the community, an effective approach, based on local source water protection programs in the U.S., would be as fol- lows. First, the entity with legal authority to ini- tiate source water protection efforts (in the case of Nicaragua this is probably the Mayor) would ini- tiate a public informational meeting. During this meeting, open to everyone in the community, Public participation is the process by which stakeholders make their views known. ------- including all stakeholders and the general public, local government representatives would introduce the subject of source water protection and related issues. Then, attendees would have an opportunity to respond with ideas, comments, questions and con- cerns. 2. Formation of a Source Water Management Planning Committee Depending on the approach of the local authority initiating the source water protection program, a small committee of individuals interested in devel- oping a management plan would be convened either prior to, or after, a general open meeting of all stake- holders and the public. This committee is the same Source Water Management Planning Committee introduced in Chapter 5, and might be composed of stakeholders, health professionals, local water utility managers, or some combinations of these groups. The job of this committee would be to develop the source water management plan according to the process presented in Chapter 5. This work would most likely be done under the direction of the local government or local water utility. The committee would also be charged with involving stakeholders and the general public periodically in the plan devel- opment process (presented in the remainder of this chapter). Later, when the management plan is writ- ten and finalized, the Source Water Management Planning Committee could transform to an imple- mentation committee and become responsible for review and modification of the plan on a regular schedule, for example every year or two years. 3. Obtaining Public Input Once the Source Water Management Planning Committee is formed, one of its first actions should be to develop a schedule of events for obtaining pub- lic comment prior to and during development of the plan. Public participation via meetings is the pri- mary mechanism to involve all stakeholders and members of the public. It is critical to clearly invite public and stakeholder comment, emphasize the openness of the process, and assure that all public and stakeholder input will be given careful consider- ation. Effective ways to publicize meetings and to solicit input on plan components are newspaper and radio announcements, posters, fliers, and word of mouth. Access to the public participation process is an important element to include when planning for public input. The lead agency needs to consider how it will reach people and organizations in remote areas of the commu- nity, as well as people with mobility, hearing, or literacy challenges. 4. Presentation of the Draft Source Water Management Plan for Public Comment The next step in public participation would be to hold a public meeting to present the draft plan to all stake- holders and the community. An explanation of what the management plan seeks to accomplish is important at this stage. Stakeholders and the general public would then review and comment upon the committee's draft proposed source water management plan. Then comments would be collected in an organized manner, often in writing or through an additional public meeting. Public Participation in Source Water Protection in Matagalpa A public participation meeting was held in Matagalpa on January 18, 2001, as part of the community's pilot project. Approximately 50 stakeholders, including cattle ranchers, coffee farmers, government rep- resentatives, teachers and students, with a vital interest in the source water protection areas around Matagalpa, attended the daylong meeting. The group discussed sources of contamination affecting their drinking water and some possible management strategies to control those sources. This meeting pro- vided an organized forum for stakeholders and members of the public to voice their own thoughts and and react to other's ideas. The outcome of the meeting was development of a list of potential contami- nant sources and a list of alternatives and management strategies for the source water areas. The pres- ence and participation of a large number of stakeholders, members of the public, and government rep- resentatives at this meeting provided strong incentive for further development of a source water man- agement strategy for Matagalpa. The schedule for public input should, at a minimum, include an initial meeting, a mid- project update and input meeting, and a draft- plan presentation meeting. Some communi- ties may wish to develop a more regular schedule of meetings at which stakeholders and the public can provide input to the plan- ning committee on a regular basis, as the source water protection plan is developed. Figure 6.2 5. Coordination with Neighboring Communities Coordination within a community, and between communities, can greatly increase the success of a source water management plan, and thus the pro- tection of key water resources. The boundaries and extent of water resources, such as a river or ground water aquifer, usually do not coincide with the bor- ders of a single community or town. Therefore, the effectiveness of actions taken in one community to protect its water source may be somewhat limited if similar actions are not taken by other communities sharing a given water source. Developing a source water management plan that is compatible with, and supportive of, the plans of other communities sharing the same water source increases the overall effectiveness of the individual community plans. Coordination with upstream communities, such as between Ocotal and its upstream neighbor Dipilto (pictured here), can greatly increase the success of a management plan. ------- 6. Media involvement Involvement of the media during development of a source water management plan can assist the process of plan development in a variety of ways. In addition to helping inform stakeholders and the public and increas- ing public involvement, the media can play a role in encouraging community support for a source water pro- tection program. Visibility in the media can also communicate the need for financial and technical assistance to government bodies, national and international NGOs, and lending institutions. A simple press release (such as that shown in Figure 6.3) can be used by the Source Water Management Planning Committee to inform the media during development of a management plan. Initiate Source Water Protection Efforts (Local Authority) Press releases such as this one, can be used by a Source Water Management Planning committee to inform the media of a source water management planning meeting. Source: Local Government Environmental Assistance Network, 2001. OnlineToolboxwww.lgean.org. Sam, Contact: [Wame, iPtmnc #\ • " S.i!.- •""« "- Won. nm^ «"• *>»IWP. To „„,, „,, ra,"'uT "'«>*>" ** u> fi* """"""""' Hold Initial Public Meeting on Source Water Management Form Source Water Management Committee * Draft Source Water Management Plan Flow chart of Public Participation in Source Water Management. * note: this step can come before or after one initial public meeting. \ Present Source Water Management Plan to the Public Finalize Source Water Management Plan Figure 6.4 Public Review and Comment Implement Source Water Management Plan Figure 6.3 Review and Revise Source Water Management Plan 7. Regular review and modification One key to the success of a source water management plan is to maintain an open dialogue with stakehold- ers and the public beyond the plan development stage (presented in Chapter 5). The Source Water Management Planning Committee should institute a vehicle for regular comment or review of the manage- ment plan once it has been implemented. This can be a good source of information for the committee about how well the plan is working and what elements of the plan are effective or ineffective. In addition, a simi- lar open dialogue should be maintained for all modifications to the plan in subsequent years after the plan is initially adopted. 6.3 Conclusion A source water management plan developed through public participation represents a consensus on how to best manage the drinking water sources for a community. The benefits gained from this process include awareness in the community about the issues relating to the protection of drinking water, institution of coop- erative networks within the community, and commitment among stakeholders and community members to implement and uphold the management plan. The public participation process tremendously increases the potential for successful source water protection. ------- 7 Case Studies from Pilot Projects 7.1 Overview 7.2 Introduction 7.3 Ocotal 7.4 Esteli 7.5 Matagalpa 7.1 Overview In an effort to develop a meaningful approach to assisting communities in Nicaragua with development of their own source water protection programs, the project began with three pilot projects in communities impacted by Hurricane Mitch. The pilot projects used different methods to address various aspects of source water management. In Ocotal, local high school students inter- ested in environmen- tal issues carried out a source water pro- tection education campaign. A com- mittee of representa- tives from the mayor's office and environmental and health organizations operating in Ocotal worked together to define the target audience and create local environmental education program, Proyecto Cuencas Matagalpa, organized a large public meeting to bring together stake- holders in the surround- ing watersheds to dis- cuss protection of the city's surface water sources. This meeting Local stakeholders attend a public participation meeting on provided a torum tor source water protection in Matagalpa. local farmers, ranchers, teachers, non-governmental organizations, students, and government representatives, and others, to voice their ideas about the threats to drinking water quali- ty in their area and what could be done to reduce them. The stakeholders also learned about source water protection from several speakers, including AYAMAT and Proyecto Cuencas representatives, and listened to each other express their opinions as well. This drawing by three local school children was used in the educational brochures distributed in Ocotal. three educational brochures. The students used the brochures, as well as a survey they had created, to inform cattle ranchers, coffee farmers and seasonal coffee workers about actions they could take to pro- tect their drinking water source. A significant portion of Matagalpa's drinking water comes from several watersheds surrounding the city. The local water supply agency, AYAMAT, and a Students in Esteli talk with workers in a furniture factory dur- ing an inventory of potential contaminant sources. Students at Esteli's campus of the National Autonomous University of Nicaragua (UNAN) pro- vided extensive time and effort to initiate a compre- hensive source water protection endeavor in that city. The students learned how to delineate source water protection areas for each of the city's drinking water wells, and then inventoried the potential sources of contamination for each protection area. 7.2 Introduction This chapter describes the three pilot projects that provided considerable basis for the preparation of this training, which is designed to assist Nicaraguans with development of programs to protect communi- ty drinking water sources. The purpose of the pilot projects was to provide technical assistance to the target communities while establishing approaches and methodologies for source water protection that could be applicable on a national level. The work in the pilot communities served to introduce ideas for watershed protection, test assumptions, gain reaction and input, and undertake initial actions to accom- plish source water protection. The selection of the pilot communities, Ocotal, Esteli and Matagalpa, was based on an initial assess- ment of conditions and opportunities for source water protection in areas damaged by Hurricane Mitch. After tentative selection, the leadership of each community was consulted to explore its inter- est and willingness to participate. The three towns ultimately included as part of the project represent locations of different population and geographic area, with differing source water management issues, in three distinct regions of the Mitch-affected areas of Nicaragua. Each pilot project was designed to address a partic- ular issue in source water management and, through empowerment to local stakeholders, to implement a specific component of source water protection: • Esteli: delineate source water protection areas for wells; • Ocotal: gain coordination and cooperation among various entities and communities in the watershed, and provide public education about contaminant sources; • Matagalpa: develop effective public participa- tion in watershed management by identifying potential sources of contamination and enumer- ating management solutions. ------- While the objective of the overall project has been to support the development of comprehensive source water protection programs in Nicaraguan communi- ties, the pilot projects were limited to just one or two components in order to focus the work and develop meaningful products within a relatively short time frame. For each pilot project, short-term objectives were identified, approaches to meet objectives undertaken, results recorded, and future needs iden- tified. The experience gained in the pilot towns has been integrated into this manual. Summaries of the pilot project case studies are pre- sented below. In addition to illustrating the unique circumstances of each community, the summaries present a concise overview of the source water pro- tection process in Nicaragua, and how it might be expected to unfold in localities beyond the pilot proj- ect communities. Mayor Marta Adriana Peralta was closely involved in development of the Ocotal pilot project. The pilot project in Ocotal was initiated in July, 2000, following a meeting between EPA representatives and Mayor Marta Adriana Peralta, during which drinking water protec- tion and its importance for the health of the community was discussed. Thanks to the enthusiastic support of the Mayor and her staff, the project got underway quickly, led by a small working group of key individuals concerned with water resources and water- shed management. The working group, organized by staff in the Ocotal Alcaldia, included community associations and non- governmental agencies, national agencies such as MAGFOR and MARENA, and inter- national organizations working in Ocotal on issues related to water quality, watershed management, and public health. 7.3 Ocotal 7.3.A Objectives • Develop partnerships among entities concerned with water quality in the community • Develop partnerships between Ocotal and the upstream communities in the source water area • Increase public awareness of source water issues and personal roles in protecting drinking water sources 7.3.B Project Summary Ocotal is a town of approximately 25,000 people, located along the Rio Dipilto in the Nueva Segovia Department in north-central Nicaragua. Ocotal depends on a central drinking water system that draws from an intake along the Rio Dipilto just upstream of the city. The water is first treated at a central facility using filtration, sedimentation, and chlorination. While the treatment plant is one of the more advanced in Nicaragua, high loads of bacteria from storm water runoff and sediment from erosion occasionally upset the balance of the treatment process and jeopardize the quality of delivered water. Upsets to the drinking water treatment system were particularly problematic in the aftermath of Hurricane Mitch. The permanent population of the Rio Dipilto watershed above Ocotal is 6,000 inhabitants, which swells to 24,000 during the four months of the coffee harvest. Approximately 25 percent of the permanent population within the watershed does not receive treated drinking water (IRENA, 1993). Instead, water is taken direct- ly from the river for household use. Therefore, both the population served by the central delivery system and the population taking untreated water from the source stand to benefit from improved protection and man- agement of source waters. This potential for improved drinking water quality provided the impetus for the source water protection pilot project in Ocotal. Initially, the working group held several discussions to identify key water quality, source water protection and public health issues in the Rio Dipilto watershed, and the most effective ways to begin to address them. Key questions raised in the meetings included: • What are the most serious water quality prob- lems affecting the health of the community? • What are the most significant potential sources of those water quality problems? • Who can and should be involved in remedying these problems? • What management techniques should be consid- ered? The identified water quality issues included cattle roaming freely in the river, runoff from coffee pro- cessing flowing directly into streams, lack of use of latrines by seasonal and permanent coffee workers, and deforestation and erosion. After the working group meetings, members of the group, along with EPA representatives, toured the watershed to observe the activities relating to identified water quality concerns. After completion of the meetings and watershed tours, the working group developed a sequence of steps to begin to address identified watershed pro- tection needs. Targeted public education was pre- dicted to yield the greatest impact in terms of over- all watershed protection. Three of the problems identified through the meetings and field visits were selected as priorities for action, based on general consensus among the working group members. These issues were: • contamination of the river by cattle, • the lack of latrine use by seasonal coffee work- ers, and • the absence of latrines available for use by sea- sonal and permanent workers in the coffee fields. Members of the Ocotal working group and EPA representa- tives toured the watershed. The Ocotal working group identified the need for increased use of latrines by seasonal coffee workers. 2 ------- The working group identified other threats to the quality of the drinking water source, but it was agreed that these matters could be addressed later in the source water protection effort. Those additional water quality issues included improperly treated and disposed coffee wastes (husks and honey water), improperly disposed trash, and deforestation. The Ocotal working group determined that broad public outreach on the priorities for action could be accomplished through the development and distribu- tion of a series of educational brochures. The brochures would deliver a clear, concise source water protection message to the target groups asso- ciated with the identified priori- ty problems: cat- tle ranchers, cof- fee farmers, and coffee pickers. In order to raise community awareness, school children were invited to design a logo for the brochures. EPA representa- The influx of seasonal coffee workers tlves developed during the coffee harvest quadruples the text and graphics area's population north of Ocotal. for separate brochures on each issue. Each brochure displayed the winning logo. Following revision and approval by the work- ing group, 300 copies of the brochures were deliv- ered to the Mayor's office for distribution. The culmination of the educational campaign was delivery of the brochures to the target populations in the watershed. Under the leadership of COBEN (the local school of Nicaraguan biologists and eologists) a group of environmentally concerned high school students was organized into two brigades to assist with the public education effort. The students iden- tified a set of coffee farms and cattle ranches within the watershed that they then visited once a week for 7 weeks. Small groups of students interviewed 9 coffee farm owners, 34 coffee pickers, and 11 cattle ranchers during their visits to get an idea of their environmental awareness and how that awareness increased over the course of the 7-week campaign. During each visit, students also distributed brochures and discussed water quality issues. The students used a questionnaire (a copy of one is included in this chapter) for guidance in their dis- cussion and interviews with each audience. Responses from the people interviewed were posi- tive, and the connection between water quality, indi- vidual action, land uses and health was conveyed successfully, according to the report compiled by the students at the conclusion of the educational cam- paign (a copy of the report pertaining to coffee pick- ers is provided in this manual). The logo for the educational brochure used in Ocotal was developed by three school children. 7.3.C Outcomes and Accomplishments The educational effort in Ocotal brought together a variety of stakeholders, all of who had interest in water resources and their management. The spec- trum of stakeholders included businesses, residents, farmers, transient and permanent farm workers, local government, water treat- ment and delivery managers, non-govern- ment organizations and students ranging from elementary to high school levels. In addition, cooperation among the several communities present in the watershed (Ocotal, Dipilto, Las Manos) was initiat- ed for the purpose of source water protec- tion. This effort helped to open new avenues of communication and strength- en ties between the communities in work- ing towards the common goal of drinking water protection. An increased awareness now exists on the part of the upstream communities that their actions to protect water quality can not only improve their own drinking water, but could also improve the water quality of downstream communities. An emerging sense of stew- ardship supports the prospect of contin- ued progress in watershed protection for the Rio Dipilto area. It is anticipated that a regional philosophy toward source water protection will become more preva- lent as communities experience the bene- fits of collaboration. Figure 7.1 The principal outcome of the Ocotal pilot project was a heightened awareness of water quality issues both in the community itself and in upstream areas. The community also gained first hand experience in designing and carrying out a public education campaign. As a result, students, coffee workers, coffee farmers, cattle ranchers and their families have an increased understanding of the primary health issue in their community: drinking water quality. Through the endeavors of the working group, connections have been made between workers, students, communities, local government offices, and local organizations. 7.3.D Future Endeavors Ocotal has established a firm foundation for continued efforts in source water protection. Primary drinking water issues have been identified, practical experience in designing and implementing a public education campaign gained, and groundwork laid for the necessary cooperative efforts that will provide optimal pro- tection of the drinking water resources in the future. A program to protect source water in Ocotal has begun in earnest, and efforts to implement a comprehensive source water protection plan, once it is developed, have a great likelihood of success. In Entr Non Non Ubi Are No. I. II. III. IV. V. VI. VII. VIII IX. forme del trabajo realizado por brigadistas ecologicos en la cuenca de el rio Dipilto en la temporada de cafe 2000-2001. evista para los ganaderos: ihre de el productor ibre de la finca sacion is de cultivo de cabeza de ffanado ^Cuantos trabajadores contrata cada a— o en su finca? Permanente H — M Temporales H — M — ^,C6mo maneja los desechos de la finca? <^asulla A------- Preparado por: Lie. Myriam Cruz Peralta, Presidente COBEN- Ocotal y Srita. Maria Patricia Lopez Aguilar, Responsable de Brigadas Ecologicas- Ocotal En el periodo de realization de las encuesta se seleccionaron a dos Brigadas Ecologicas, conformada por estudiantes de secundaria de V ano de el Colegio Fe y Alegria integrado por los jovenes: Brigada" Las Golondrinas" (7 mujeres) y Brigada" Los Chacales" (8 hombres). Estos jovenes brigadistas se movilizaron en grupos de tres en las fincas cafetaleras de Dipilto Viejo, El Volcan y Las Manos en el municipio de Dipilto, visitaron un total de nueve fincas cafetaleras, en las cuales realizaron un total de treinta y cuatro entrevistas a cortadores de cafe de ellos (12 mujeres) y (22 hombres) estas personas entrevistadas ano con ano regresan a las mismas fincas a cortar cafe y lo hacen acompanados de sus hijos menores y su companera o companero. Asi contestaron a las preguntas los cortadores de cafe I. ^Esta preocupado por la calidad de el agua que toma? Esta sucia y contaminada, sale oscura y con mal sabor, les preocupa que se puedan enfermar porque sale de la quebrada (rio), porque es necesario clorarla, por la salud de su familia, por la pulpa de el cafe. II. ^Sabe usted que cuando las personas y los animales tiran desechos al rio pueden enfermarse al tomar de esta misma agua? Si: No, explique por favor: Si, porque al tomarla ellos mismos pueden morir, porque ellos la consumen, esta infestada, por las enfermedades, se contamina su organismo, perjudica la salud, el desaseo. Hay microbios que viven en los excrementos y orina, humana y animal, que no pueden ser vistos. Cuando llueve, si hay excrementos en las partes altas del rio (cuenca), estos desechos pueden caer al rio llevando consigo los microbios. Si hay ganado en el rio o cerca de el, estos microbios en los desechos tambien caeran al rio. Cuando bebe agua que contiene estos microbios invisibles puede darle fiebre, diarrea, vomitos, dolor de estomago, dolor corporal, y deshidratacion. A veces estos sintomas pueden causar la muerte, especialmente, a infantes, nifios y ancianos. III. i, Se ha enfermado alguien en su familia recientemente, o conoce a alguien que haya estado enfermo por las causas anteriores? Si, la enfermedad fue causada por haber tornado agua "sucia." No, estamos contentos que siga saludable aunque otras personas no hayan tenido la misma suerte. Si, se han enfermado presentando dolores de estomago. Se enfermaron los ninos solamente dos, los restantes dijeron que no porque hierven o cloran el agua. IV. Hay cosas que se pueden hacer para proteger el agua de los microbios; entre estas se destacan: • Usar las letrinas disponibles • Mantener las vacas fuera de el rio ( entre mas lejos de el rio mejor) • Incluso los afluentes son importantes porque ellos suplen al rio V. i Preferiria usar letrina si existieran? Si, No ^Por que? Por que necesitan hacer sus necesidades, si no hay tienen que hacerlas al aire libre y luego enterrarlos, para prevenir enfermedades, para evitar la contamination, por las moscas, para protegerse, por que es necesario tenerlas, ayuda a nuestra salud, por limpieza y seguridad, es importante para evitar los microbios. VI. ^Considera que debe cuidar su salud, utilizar las letrinas y cambiar algunos habitos de higiene? • Concienciar a los que la usan • Para cuidar nuestra salud • Lavarse las manos • Clorar o hervir el agua • Para no contaminar el agua • Para mantener limpio • Vivir aseados • Lavar los alimentos • Mantener las letrinas cerradas por las moscas • Porque haciendolo al aire libre podemos contraer enfermedades • Tapar el agua • Usar papel higienico y quemarlo • Limpiar o cambiar las letrinas • No mantener animales en la cocina VII. Brinde su opinion sobre: • El uso de las letrinas. • Mantener el ganado fuera de el rio. Se pude hacer esto, y si no se puede £Por que no? Puede sugerir algunas otras cosas para que esto pueda hacerse (el uso de las letrinas y alejar al ganado de el rio)? Es importante usar letrinas, se puede mantener limpia la letrina, es primordial tenerla para que nadie se enferme, donde hay agua puede haber ganado por que tienen microbios, es importante por la salud, se debe llamar la atencion a personas que no mantienen limpia la letrina, porque se mantiene el agua limpia y se protege la salud, el ganado debe estar encerrado, las letrinas son muy utiles, es necesario hacer buen uso de las letrinas y mantenerlas aseadas, es una buena medida para evitar enfermedades y contaminar el agua. VIII. i, Hay algunas otras acciones que puedan ser tomadas para mantener los excrementos (humanos / de animales ) fuera de el alcance de el rio? • El uso de las letrinas. • Es dificil por que mucha gente busca el campo para hacer sus necesidades; por ejemplo: en una fmca de 80 trabajadores solo 3 usan letrina. • Se debe enterrar los excretos. • Se debe mantener tapada la letrina. • Mantener los animales encerrados. • No llevar el ganado al rio. • Usar los excretos como abono. • Beber agua de pozo. • Orientar a la poblacion sobre el asunto de las letrinas. • Aumentar el numero de letrinas en las fincas. • Dejarla de abono en la fmca. • Meterla en un hoyo, despulpar en seco el cafe, dejarle de abono. Figure 7.2 ------- 7.4 Esteli: 7.4.A Objectives • Delineate Source Water Protection Areas (SWPA) for Esteli wells • Inventory potential contaminant sources for all SWPAs for all wells • Rank potential contaminant sources in all SWPAs for wells • Engage students, mayor's office, and other key agencies and organizations in the city in a source water protection effort • Develop coordination between the university and the mayor's office 7.4.B Project Summary The city of Esteli was chosen as a pilot project com- munity for several reasons: the relatively large size of the community, the fact that Esteli depends on ground water sources for its drinking water, the presence of the University Center of the Northern Region of UNAN (UNAN-CURN) there, and inter- est on the part of the Mayor. An exploratory meet- ing with the Mayor took place in July, 2000, and a project to delineate the source water protection areas for wells in Esteli was launched soon thereafter. Esteli is served by 16 drinking water wells, most of which are located in or immediately adjacent to the urban center. During initial discussions with the Mayor, concern for the longevity of these wells became evident, as did the community's interest in developing a base of technical information about the wells and surrounding areas that would assist in the management of these drinking water sources. EPA representatives were aware of the existence of a branch of UNAN located in Esteli, and, with the support of the Mayor's office, approached the direc- tor of the Environment and Natural Resource Management Program about student participation in a source water protection area delineation project for the drinking water wells in the city. The director of the program, Dr. Ramona Rodriguez Perez, enthusi- astically supported the proposal, and worked closely with EPA representatives to formulate a credit proj- ect for third year graduate students in the environ- mental and natural resource management program. The woodworking factory and tile factory, shown here, were toured by UNAN-CURN students as part of their inventory of potential sources of contamination. The UNAN-CURN delineation project involved 25 students who participated in two EPA training ses- sions, one in November, 2000, and one in January, 2001. During the first class, students learned how to perform delin- eations of source water protection areas for wells, using the calculated fixed radius equation (based upon recharge and pumping rates) presented in Chapter 4 of this manual. After the first class, the students calculated candidate radii for all 16 wells serving the city. They then developed a map show- ing the circular source water protection area for each well. These calculations were based on an estimat- ed recharge rate (assumed to be 50% of the annual precipitation rate), and 100% of the pumping capac- ity of each well, as suggested by the trainer for this first exercise. During the second class, EPA repre- sentatives verified the protection area calculations and provided instructions on methods to inventory potential sources of contamination within the mapped areas. The second classroom session was immediately fol- lowed by a field trip to identify potential sources of contamination in one of the delineated areas and to collect information needed for the ranking process. The students chose a protection area for a well near the UNAN-CURN campus and walked throughout the protection area as a group with the EPA repre- sentatives. A variety of potential contaminant sources were investigated, including a woodworking shop, a tile factory, road runoff, and sewage and storm water discharge pipes from homes and busi- nesses. Students' knowledge of the importance of positive collaboration in the pursuit of drinking water protection goals was put into practice during discussions with owners and operators of potential contamination sources. The field trip concluded with a visit to the site of the well that currently draws water from the delineated area they had just toured, underscoring the potential impact of activities with- in the protection area on drinking water quality. During the months following the second class, the students identified potential sources of contamina- tion in each of the delineated source water protection areas. They first developed a list of potential sources of contaminants that applied specifically to the land uses and industries in their town, and then walked throughout each pro- tection area to directly investigate all the potential contaminant sources. In the process of the investi- gation, the students talked with shop own- ers and other local people about the chemicals used, stored or disposed of at their facility, business or home. They also col- lected data on methods used by local shops and fac- tories for chemical and waste storage and disposal. The students will use this information in the future when they rank the potential contaminant sources, based on potential risk and other factors, in order to develop management options. (Ranking of potential contaminant sources is discussed in more detail in Chapter 4.) This inventory exercise provided the students a clear understanding of the potential threats to the drinking water supply, and provided a basis for discussion of drinking water protection with the business owners, workers, and local agen- cies. The final piece of the UNAN-CURN graduate class project will be to rank the potential sources of con- tamination based on a set of chosen criteria, such as travel time to the well, quantity of contaminant, or type of contaminant. (Ranking is discussed in more detail in Chapter 4.) Ranking sources will help the students to evaluate the potential risk to drinking water supplies from the sources. This information will then be shared with the municipal government to facilitate efforts to implement source water pro- tection measures. As the students worked on the source water area delineations, word about the project spread within ------- The students at UNAN-CURN delineated the source water pro- tection area and conducted an inventory of potential contami- nation sources for Well #18 in Esteli, pictured here. the community. Others began to take an interest in the project, in particu- lar, AMCRE (Association of Municipalities of the Esteli River Watershed). Thanks to the initiative of the university, AMCRE became involved in the project. Applying its Geographic Information System (GIS) capabilities, AMCRE will work with students to digitize the maps of the source water pro- tection areas for the Esteli wells. This effort will make the source water protection area information compatible with a variety of software applications, and thus highly useful to other institutions working in the area on natural resource management and drinking water and watershed protection. The students also established a working relationship with the local office of ENACAL, which supplied information on well locations, pumping rates, and other design specifics. Project results will be made available to the ENACAL office to assist in opera- tion and management decisions, and in planning for future service needs. A continued working relation- ship among the University, the municipality, AMCRE and ENACAL can move the source water protection effort forward into the management stages. Currently, the project is being carried ahead primarily by the work of the students at UNAN- CURN. Over time, the political leadership of the municipality and ENACAL most likely will become integral players in implementing management options. The students and professors at UNAN- CURN hope to continue working on the topic of source water protection with future classes, and to maintain the working partnerships established dur- ing this project. Continued involvement of students at the University is likely to strengthen source water protection efforts in Esteli. 7.4.C Outcomes and Accomplishments Students in the source water protection class at UNAN- CURN each received a certificate of completion. A number of noteworthy achievements resulted from the Esteli case study effort. The most out- standing of these was demonstration of the value of involving University students in providing technical support for drinking water protection efforts. The interest, competence, and dedication of the students and faculty involved in this project indicate that expansion of university involvement in source water protection efforts throughout Nicaragua would be a valuable component of long-term programs. In terms of the UNAN-CURN class specifically involved in the pilot project, the students developed skills and understanding that can be put to work in the immediate future. Their determination that almost every part of the city of Esteli falls within a protection area, established an important connection for the students between land use and the potential for drinking water contamination. Other projects related to the delineation effort are being developed and collaborative efforts between the University and the local government to develop components of a source water protection program have begun. As a result of this project, the city of Esteli now has a calculated and mapped set of candidate source water protection areas, and corresponding invento- ries of potential contaminant sources, for its 16 drinking water wells. The students can now use this information as a tool in pursuing the next steps in source water protection, along with the help of ENACAL, the municipality, AMCRE and other stakeholders. Another positive outcome of the pilot project was development of a comprehensive inventory of potential contaminant sources in each source water protection area, and the ranking of potential sources of contamination within each of these areas. It is anticipated that this information will be of consider- able benefit to the local government, which has indi- cated a strong interest in initiating a comprehensive drinking water protection program for the city. 7.4.D Future Endeavors Professors at the University have expressed an inter- est in continuing to develop coursework relative to drinking water protection. This will likely be cov- ered as part of the Physical Chemistry and Toxicology track in the Natural Resource Management Masters program (Gestion en Medio Ambiente y Recursos Naturales) at UNAN-CURN at UNAN-CURN Esteli. The students who received the training as part of the pilot project may continue with efforts to protect drinking water in Esteli or undertake similar work elsewhere. Indications from the Mayor's office are that the work of the students will contribute significantly to source water protec- tion efforts in the community, and that this project has provided the impetus to begin to assemble a citywide strategy for drinking water protection. The students who have participated in the pilot project in Esteli may continue with efforts to protect drinking water in Esteli or elsewhere. The contributions of the agencies and individu- als involved in the pilot project efforts in Ocotal, Esteli and Matagalpa have been invaluable in Nicaragua's effort to establish a national pro- gram to protect drinking water sources. Their assistance is greatly appreciated. 6 ------- 7.5 Matagalpa 7.5.A Objectives • Public participation in source water protection • Enhanced local management of drinking water sources • Development of a wash basin demonstration project 7.5.B Project Summary Matagalpa is a mid-sized city lying at the con- fluence of the Rio Molino Norte and the Rio San Francisco. Matagalpa draws its water from three major sources: the Rio Molino Norte, the Rio San Francisco and the Rio Aranjuez. AYA- MAT is also currently investigating the possi- bility of drawing additional water from ground water sources in the Sebaco Valley, Chaguitillo. The pilot project in Matagalpa built upon the activities of an existing network of local water- related groups, and focused on facilitating dis- cussion of drinking water issues among stake- holders in the various watersheds that supply surface drinking water to Matagalpa. The source water protection areas for the combined surface and ground water drinking water sources in the Matagalpa region are vast. A local environmental education program, Proyecto Cuencas Matagalpa, has mapped these source areas for its own educational purposes, so the watershed boundaries around Matagalpa are generally recognized and understood by the community and water resource and envi- ronmental managers in the region. The effort by Proyecto Cuencas Matagalpa to delineate the watersheds and educate the community on the subject appears to have greatly facilitated source water protection efforts and management activities in and around Matagalpa. Matagalpa is unique in that its drinking water is managed by an innovative prototype organization called AYAMAT AYAMAT is a semi-private entity related to ENACAL working to manage protection and delivery of drinking water in a sustainable and efficient manner, with limited involvement by ENACAL. Matagalpa is also unusual in that it has a very strong, well-established environmental organization in place in the commu- nity. Proyecto Cuencas Matagalpa works with local community members and students to provide environ- mental education, promote environmental campaigns at the local level, and support innovative, environmen- tally friendly, and economically beneficial alternatives to habitual activities that contribute to the degradation of drinking water sources. The Matagalpa pilot project capitalized on the successes of these institutional arrangements to initiate a sustained public involvement program for the source water protection areas. The first step in developing the source water protection program in Matagalpa was to work with AYAMAT and Proyecto Cuencas Matagalpa to organize a stakeholder meeting to discuss the major problems affecting A community clothes washing station in Matagalpa could help pre- vent bacteria and harsh soaps from flowing directly into the river. drinking water quality, and to develop new ideas and options for mitigating those problems. On January 18, 2001, representatives of EPA, AYAMAT and Proyecto Cuencas Matagalpa facilitated a meeting of approximately 50 stakeholders who had been identi- fied and invited to participate by AYAMAT and Proyecto Cuencas. Proyecto Cuencas Matagalpa was able to use its existing network from its ongoing environmental education and outreach work to iden- tify a large group of stakeholders from throughout the surrounding watersheds. The stakeholders repre- sented the following interests: • Members of Proyecto Cuencas Matagalpa • Local government officials • Town water committees • MARENA-Matagalpa • National Forestry Institute (INAFOR) - Matagalpa • Health organizations • Small Producers Association of Molino Norte (a watershed that supplies drinking water to Matagalpa) • Cattle ranchers • Farmers (large- and small-scale): vegetables, grains, corn, coffee • Tree nursery operators • Dairy farmers • School teachers • Students from National Agrarian University in Managua The first half of the day was devoted to key topics in watershed management, including: • source water assessment and the benefits of pro- tection; • the role of public participation in protection of drinking water sources; • the Proyecto Cuencas Matagalpa and current efforts underway to improve and protect source waters for Matagalpa drinking water; and • alternative technologies and practices to address potential contamination associated with the coffee industry. In the afternoon, EPA representatives led a discus- sion of the major contaminant issues in the source water areas of Matagalpa, and what might be done to mitigate the contaminants. The meeting became lively at points, with participants expressing their ideas over a spectrum of economic, political, educa- tional and social perspectives. While significant dif- ferences of opinion emerged over the course of the meeting, many vital issues were put forth for discus- sion. Ultimately, the group identified nine signifi- cant sources of contamination: • Honey waters from coffee processing • Trash - plastics, wrappers, glass • Cattle ranching • Clothes washing directly in the rivers • Dairy farming • Leather processing • Pesticides and chemicals used in high volumes on flower farms • Sewage waste • Deforestation (effects on quality and quantity of water) The discussion clearly bolstered the process of source water protection. Several of the participants made a point to say that the meeting was well worth the time spent and they were glad to have participat- ed. Others felt the community needed to have more meetings of a similar nature to discuss issues and initiate action. In general, the group concluded that more education on drinking water quality and pro- tection was needed in the watershed communities. One of the major themes emerging from the public meeting was the need for and interest in alternative technologies to reduce negative impacts on water quality and watershed ecosystems. Alternatives dis- cussed included the following: • Use of coffee pulp as an organic fertilizer; • Use of biogas instead of wood; • Reduced use of water in coffee processing; • Treatment of honey water; • Use of the inner coffee husk to form energy bricks ------- to reduce wood consumption; Use of more efficient ovens; and Use of community clothes-washing stations locat- ed away from the river. Participants in the public participation meeting in Matagalpa tour the coffee waste treatment technologies at Selva Negra. 7.5.C Outcomes and Accomplishments Based on the feedback of participants, the Matagalpa public meeting was clearly effective in raising the level of awareness of watershed issues, and in gen- erating interest to resolve them. Some of the more notable successes were the large number of partici- pants, the broad representation of diverse interests from a large geographical area, and the considerable interchange that took place among the presenters and audience. Such interaction is a critical element of the source water protection process. The presence of several government representatives at the meet- ing, from international, national and local levels, gave people a sense that their ideas and comments mattered, and further added to the momentum gen- erated by the meeting. In the future, further discus- sion of issues surrounding source water protection and management can be hosted through the outreach network of Proyecto Cuencas Matagalpa. The Matagalpa public meeting was also an opportu- nity to showcase one of the leading examples of local source water management in Nicaragua. It was evident from the discussions over the course of the day that AYAMAT is in a unique position to react to the issues brought up at the meeting and to work with the watershed communities to continue the effort of source water protection. As more people become aware of the existence and operation of enti- ties like AYAMAT, local communities may be stim- ulated to apply the model to their own situations and, in the process, bring source water protection efforts closer to home. Leaders from Proyecto Cuencas Matagalpa and AYAMAT use this watershed map (above) and 3-dimensional model (below) to point out potential contamination sources and drinking water intake locations. 7.5.D Future Endeavors The Matagalpa public meeting laid the foundation for a highly participatory public involvement process in the creation of a source water protection plan for the region. EPA representatives promoted the idea of further meetings as a means of keeping attention focused on water quality issues and gener- ating action. During the public meeting, one of the issues raised was the impact of clothes washing on river water quality. From this discussion emerged the idea of constructing a community wash station set back from the river and supplied by water diverted from the river. The wash water could be directed to an infiltration area to prevent discharge directly to the river. This wash station, which could accommodate a small number of families, could be used as a demonstration project for other similar projects in the future. Such a facility could serve as a model and encourage broad scale use as a means to protect surface water quality. ------- Innovative and Alternative Technologies 8.1 Introduction 8.2 Innovative and Alternative Technologies Applicable in Nicaragua 8.1 Introduction We are continually increasing our own awareness about the negative impacts of human activity on environmental resources. For example, the use of rivers to discharge industrial and municipal waste- water, the application of agrochemicals to crops, and the practice of burying hazardous wastes have been recognized as major causes of environmental dam- age and, in some cases, human health problems. In response, communities and societies around the globe have begun to undertake efforts to adapt activ- ities and to develop innovative practices that better protect resources and ecosystems. In particular, many effective innovative and alterna- tive technologies have been developed to address water pollution problems both at the community and the individual level. Conventional practices, such as disposing of coffee husks and honey waters from coffee processing directly into a surface water body, washing clothes directly in a river, and allowing cat- tle to roam directly into a river to drink, sometimes have associated environmental costs like pollution of water resources. Innovative and alternative tech- nologies are ways of meeting community needs such that negative environmental impacts are reduced or eliminated. Some innovative and alternative technologies are now being applied in communities in Nicaragua that are working to reduce contamination in the water- sheds, achieve cleaner drinking water, improve envi- ronmental health, realize cost savings, and limit the overuse of resources. The benefits to drinking water quality from the use of innovative and alternative technologies can be significant. Therefore, a chapter of this manual is devoted to summarizing several of these. As drink- ing water resource management plans are devel- oped in the communities of Nicaragua, it is impor- tant to consider how and where innovative and alternative technologies can be employed. Whether taken as a direct application of the alternatives pre- sented here, an adaptation of them, or a formulation of altogether new approaches, innovative technolo- gies can significantly increase the success and/or reduce the cost of a drinking water protection pro- gram both at a national and local level. Water resource managers and other leaders should pursue opportunities for developing new and alternative technologies. It should be noted that three of the innovative and alternative technologies presented in this chapter could result in pollution of groundwater. The bene- fits gained from clothes washing stations, cattle watering troughs away from surface waters, and latrines all rely on the process of filtration for con- taminant removal. The percolated water can eventu- ally reach the ground water, with the slight possibil- ity of carrying with it nutrients, viruses and bacteria from cattle waste, human waste and clothes washing water. These technologies could potentially cause pollution of groundwater resources. While these technologies may not be ideal in terms of protection of water supplies, they do provide a marked improvement over direct discharge to surface waters that serve as sources of drinking water. Finally, it is also important to note that in Nicaragua, personal property taxes or improvement taxes may be imposed on certain types of new construction. This fact may act as a deterrent to individuals who might otherwise employ an alternative technology. A significant initial investment, sometimes required to institute a technology, might also be a disincentive for implementation. An effort to eliminate such dis- incentives could include working with the local municipality to develop a program of tax breaks or other incentives as part of the source water protec- tion and management plan (see Chapter 6 for further discussion). Firewood collection contributes to unstable conditions on hill- sides leaving them vulnerable to erosion. 8.2 Innovative and Alternative Technologies Applicable in Nicaragua 1) Fuel bricks from coffee husks (cascarillas) According to Proyecto Cuencas Matagalpa, a water- shed protection program in Matagalpa, fuel bricks (briquetas) can produce more energy than a similarly sized log of firewood. Several neighborhoods in the north of Matagalpa have begun using briquetas for fuel (Proyecto Cuencas Matagalpa, 2000) instead of wood. The coffee husk bricks can replace some of the need for firewood, which is already sparse on many hillsides due to previous deforestation. Further cut- ting of trees for firewood promotes unstable condi- tions on hillsides, and leaves the terrain vulnerable to erosion. Erosion of soils from the hillsides can cause heavy sedimentation in rivers and streams, which can impact the quality of drinking water sources. Using coffee husks for fuel bricks or purchasing fuel bricks instead of firewood can slow the rate of deforestation on hillsides. The recycling of coffee husks in this manner also reduces the practice of discharging husks directly into surface waters, which is a typical means of disposal during the coffee harvest season. Fuel bricks produce more energy than a similarily sized log of firewood. ------- 2) Composting of coffee husks (pulpa de cafe) for fertilizer Coffee husks can also be composted (allowed to decom- pose in a pile) and used for fertilizer the next year. Coffee husk composting requires construction of a sump or basin, usually built of cement or brick, in which the coffee husks can settle out of the honey waters. The honey waters are diverted elsewhere for further treatment and the coffee husks are moved to a compost area. A separate area near the settling basin must be designated where the husks can be composted. This area can be a simple hand-dug hole in the ground or just an open space for a compost pile. It is estimated that recycling husks from a coffee farm can pro- vide fertilizer for approximately 20 percent of that farm (Kuhl, 2001), potentially cutting fertilizer costs by 20 per- cent. Cost savings on fertilizer can therefore cover the ini- tial construction cost for the settling basin rather quickly. Coffee husk composting can be instituted on a farm of any size. Coffee husks can be collected, composted, and turned into fertilizer. 3) Biogas production from biodigestion of honey waters in coffee production Honey waters produced in wet coffee processing (lavado del cafe) are extremely high in organic mate- rial (such as sugars). When this material is broken down by naturally occurring bacteria, methane gas is produced. This process is called biodigestion, and can be carried out in a biodigester tank (see photo at right). The methane is captured within the tank and delivered to homes via simple pipe systems for use in cooking. Use of biogas as a fuel is usually only effi- cient when it can be produced near the area where it is used. The gas can be used as a cooking fuel in place of wood. Proyecto Cuencas Matagalpa has been working with area coffee farms to construct and implement the use of biodigesters to produce biogas. At least four farms have begun to use the biogas they are producing in their biodigesters (Proyecto Cuencas Matagalpa, 2000). Biogas produced from the decomposition of coffee husks can be collected and used as a fuel source. 4) Clothes washing station Washing clothes in a river can contribute significant amounts of bacteria and soaps to the river. By wash- ing clothes away from rivers, the pollution load from soiled clothes and soap can be minimized or eliminat- ed. Clothes washing stations for small communities or neighborhoods can be constructed in convenient loca- tions away from rivers. Typically, a pipe is construct- ed and water is transported via gravity or pumped from the river to a cement wash station at least 100 meters from the edge of the river. The discharge water from the wash station is directed to a specified location to infiltrate into the ground before it returns to the river. Washing clothes away from rivers prevents bacteria and soap from entering a surface drinking water source. Infiltration allows bacteria to be filtered out of the water by the soil, and absorption or uptake of the nutrients in soap to take place. Any water returning to the river via underground flow has lower levels of pollutants. Ready-made washbasins, as well as piping, fittings, and valves can be purchased in most large towns. A community may wish to form a small management board to take care of maintenance and management of a community wash station. Money is usually required for upkeep of the system, or for power for a water pump, if one is used. Possible sources of funds include the local government, water utilities, non-govern- mental organizations working in the area, and user fees. Each community must determine the best method to support the day to day operation and maintenance of a wash station. 5) Watering troughs Keeping cattle or other livestock out of rivers and streams is essential to protecting surface water quali- ty. Excrement and urine from livestock can be a major source of drinking water pollution. One method to restrain livestock is to fence off surface water bod- ies and provide animals with an alternative source of drinking water. A trough of water located well away from a river or stream can be supplied with water from upstream via a gravity pipe or by pumping it up from the river if necessary. While construction of troughs and fences may require a significant initial investment, and maintenance needs can be high, the benefits to water quality from reduced bacteria and nitrogen entering a surface drinking water supply can be considerable. Similar to wash basin projects, sources of funds might include local governments, water utilities, non-governmental organizations work- ing in the area, and user fees. Water troughs must be provided for livestock restrained from rivers and streams by use of fencing. ------- 6) Public/community latrines One of the sources of bacterial inputs to rivers and streams is overland runoff of human waste. In an effort to reduce open defecation in unvegetated areas, especially roadsides, communities could invest in public latrines in critical locations. Such locations might include bus stops, coffee pick-up stations, mar- kets, and other sites where people typically gather for periods of time. Public latrines would need to be sited and built in a manner protective of water supplies. They should be located away from rivers and streams and should be designed to ensure that wastes are fil- tered into the ground rather than carried off in any storm runoff to a surface water body. Public latrines in gathering places like local markets can reduce the need for open defecation. 7) Sand filters Sand filters can be used for cleansing relatively small volumes of surface water or spring water for individual dwellings and small communities at higher elevations where bacterial contaminants are less likely to occur in high concentrations. Ideally, sand filters would be used as one step in a series of water treatment steps that would also include disinfection, such as chlo- rination. However, even in the absence of possible further treatment options, filtration of drinking water is a worthwhile practice. Because of the relatively limited capacity of sand filters to reduce contamination levels in water, they are only practical in areas where bacterial and other contaminant inputs are relatively low. Typically, the least contaminated surface waters occur close to the water sources in the upper watersheds. An example of a region that could benefit from increased use of sand filters is the higher elevations in the Rio Dipilto watershed. Sand filters can be effective in filtering out some particulate matter, such as suspended sediments and particulate metals from water. Basic sand filtration can also remove some bacteria that may be attached to particulate matter in the water. Water is diverted from a stream or river and dispersed at a slow rate of flow through a container of sand, collected at the bottom of the container, and piped by gravity flow to the home or homes using the supply. Sand filters of varying sizes can be con- structed depending on the volume and flow of water to be cleaned on a daily basis. It is very important to size the sand fil- ter appropriately for the volume and flow of water being treated in order to allow for the maximum contaminant removal. An improperly sized or maintained sand filter could be virtually ineffective, or could harbor growth of bacteria or build-up of contaminants within the sand bed. The sand should be clean and should be replaced frequently, depending on the level of bacterial contamination of the water. Finally, the top of the sand filter should be covered, while still maintaining plenty of open air circulation for the sand and water, in order to prevent contamination from animals. ------- Sources of Information 9.1 Nicaraguan Local and National Government Organizations 9.2 Foreign Government and Multilateral Organizations 9.3 Non-Governmental Organizations 9.4 Educational and Research Institutions 9.5 Documents from the Pilot Project Arena That May Be Useful One of the most important pieces in the source water protection process is accessing the available body of information about the source water area of interest. There is no need to start from scratch when information may already exist about: land uses in the watershed, water quality, topography, water distribution, current management, and other relevant topics. In addition, experiences from source water protection efforts in other areas can be helpful in planning a local effort. Below is a list of possible sources of information in local communities and in the greater national and international community that may be of help. A majority of this contact information was gathered from web sites hosted by the organizations listed below, and is as current as the infor- mation provided on the web site. All web site locations and contact information otherwise collected are current as of May, 2001. 9.1 Nicaraguan Local and National Government Organizations Local Alcaldia Planning and land use information Statistics about population, land uses, local programs Empresa Nicaraguense de Acueductos y Alcantarillados (ENACAL) Km 5 !/2 Carretera Sur Contiguo a la Casona E.E.U.U. Managua, Nicaragua Tel: 505-265-0861 Fax: 505-265-0981 Local offices may also be able to provide: Well Information Water Service and Distribution Information Acueductos y Alcantarillados de Matagalpa (AYAMAT) Contiguo a Interbank Matagalpa, Nicaragua Tel: 505-6125461, 6122979 Fax: 505-6123148 Institute Nicaraguense de Estudios Territoriales (INETER) Direccion de Recursos Naturales Frente a la Policlinica Oriental del Seguro Social Apdo. Postal 2110 Managua, Nicaragua Tel: 505-249-2756 Fax: 505-249-1890 Topographic maps Map of major watersheds in Nicaragua Map of average annual precipitation in Nicaragua Map of average high precipitation in post El-Nino years in Nicaragua Hydrogeologic Maps and Cross-sections Ministerio Agropecuario y Forestal (MAGFOR) www.magfor.gob.ni (Spanish) Agricultural and forestry resources Soil information Land use information Planning and land use information Statistics about population, land use programs Ministerio de Salud (MINSA) Complejo Nacional de Salud "Dra. Conception Palacios" Costado Oeste Colonia Primero de Mayo Managua, Nicaragua Tel: 505-289-7274, 289-7235 www.minsa.gob.ni (Spanish) Public health information Water quality information in some water treatment plants Ministerio del Ambiente y Recursos Naturales (MARENA) Direccion General del Ambiente y Recursos Hidricos (DGA) Km 12 Vi Carretera Norte Apartado Postal 5123 Managua, Nicaragua Tel: 505-263-2095/263-2088 Fax: 505-263-2088/263-2354 Asociacion Municipios de la Cuenca y Subcuencas Tributarias delRioEsteli (AMCRE) Esteli, Nueva Segovia, Nicaragua Tel: 505-713-7725 Fax: 505-713-6721 [email protected] 9.2 Foreign Government and Multilateral Organizations US Environmental Protection Agency Office of Water Home Page www.epa.gov/OW/index.html (English) Office of Ground Water and Drinking Water Home Page www.epa.gov/safewater (English) El agua potable y la salud: lo que Ud. debe saber www.epa.gov/safewater/agua/apsalud.html (Spanish) Estandares de Agua Potable en Los Estados Unidos www.epa.gov/safewater/agua/estandares.html (Spanish) Drinking water contaminants - Fact Sheets www.epa.gov/safewater/hfacts.html (English) ------- Safe Drinking Water Help Line: www.epa.gov/OGWDW/drinklink.html (English and Spanish) Tel: 800-426-4791 (toll free from the US) US Peace Corps Colonia Bolonia Canal 2, Ic. Abajo, 2 cuadra al sur Managua, Nicaragua Tel: 505-266-7033/ 266-7034/ 266-7035/ 266-7036 Fax: 505-266-1392 US Agency for International Development (USAID) Nicaragua Mission De la Loteria Nacional, 200 metros abajo Frente a Syscom Pista Sub-Urbana, Apartado Postal C-167, zp-13 Managua, Nicaragua Tel: 505-267-0502 Fax: 505-278-3828 www.usaid.org.ni (English) USAID Environmental Health Project Del Hotel Colon Ic. al sur, 1 /^ arriba, Los Robles Managua, Nicaragua Tel: 505-270-2380, 505-270-2517 Fax: 505-278-4961 www.ehpnicaragua.org.ni (Spanish) The World Bank De los Semaforos de la Centroamerica 400 mts. Abajos, segundo piso Edificio SYSCOM Managua, Nicaragua Tel: 505-270-000 Fax: 505-270-0077 www.worldbank.org (English) United Nations Development Program Rotonda El Gueguense Plaza Espana 400 mts al sur Apartado Postal 3260 Managua, Nicaragua Tel: 505-266-3191, 505-266-3193, 505-266-3195 505-266-1701, 505-266-3155 Fax: 505-266-6909 www.undp.org.ni (Spanish) The World Health Organization Home Page www.who.int/home-page/index.es.shtml (Spanish) Links to Environment and Health related information http://www.who.int/home/map_ht.html#Environment and Lifestyle (English) Drinking water quality information and contaminant guidelines http: //www. who. int/water_sanitati on_health/Water_quality/ drinkwat.htm (English) http://www.cepis.ops-oms.org/indexeng.html (Spanish) Pan American Health Organization Oficina Sanitaria Panamericana Complejo Nacional de Salud Apartado Postal 1309 Managua, Nicaragua Tel: 505-289-4200, 505-289-4800 Fax: 505-289-4999 www.ops.org.ni (Spanish) Information about health, links to technical documents and references about diseases and disease prevention, databases, and contact infor- mation Comite Coordinador Regional de Instituciones de Agua Potable y Saneamiento de Centroamerica, Panama y Republica Dominicana (CAPRE) Avenidas Central y Primera, Calle 5 Edificio la Llanuca, Piso 15 Apdo. Postal 5120-1000 San Jose, Costa Rica Tel: 506-222-4392/257-6054 Fax: 506-222-3941 9.3 Non-Governmental Organizations CARE International Sandy's Carretera a Masaya Ic. abajo, /^ c. al lago Apartado Postal 3084 Managua, Nicaragua Tel: 505-267-8395, 505-278-3834, 505-278-0018, 505-278-0115 Fax: 505-267-0386 CARE International supports rural water, sanitation and preventive health projects in communities in Nicaragua. These projects include PALES A, the El Viejo Potable Water project, the Latrines and Health Education Project, and the Water for Today and Tomorrow project. For more information, visit www.care.org.ni. (Spanish) Amigos de las Americas Amigos de las Americas, a Non-governmental organization from the United States, brings volunteer teams to work with small communi- ties on sanitation, environmental education, and drinking water proj- ects, as well as on other community development issues. In Nicaragua, AMIGOS' partner organization is CARE International (see above). Auxilio Mundial - World Relief Managua, Nicaragua Tel: 505-265-3415, 505-265-3430 Agua Para la Vida 2311 Webster Street Berkeley, CA 94705, USA Tel: 510-643-8003,510-528-8318 Fax: 510-643-5571 Agua Para la Vida is a non-profit organization started in 1987 to help start small rural Nicaraguan communities to construct their own drinking water systems. 9.4 Educational and Research Institutions Centre Agronomico Tropical de Investigation y EnseiTanza (CATIE) 7170 CATIE Apdo. Postal 19-7170 Turrialba, Costa Rica Tel: 506-556-6081, ext. 337 Fax: 506-556-6166 Proyecto Cuencas Matagalpa Edificio Alcaldia de Matagalpa Planta Alta Matagalpa, Nicaragua Tel: 505-612-2850 cuencama(S)ib w.ni. com ------- Environmental education project to protect the watersheds around Matagalpa Universidad Nacional Autonoma de Nicaragua (UNAN) UNAN - Managua ENEL Central 3 Km al Sur Apartado Postal: 663 Managua, Nicaragua Tel: 505-278-6769 Fax: 505-277-4943 www.unan.edu.ni (Spanish) Universidad Nacional Autonoma de Nicaragua (UNAN) Centre Universitario Region Norte (CURN) Programa de Gestion en Medio Ambiente y Recursos Naturales Esteli, Nicaragua Tel: 505-713-2437, 505-713-6890 Universidad Centroamericana de Managua (UCA) Pista de la Resistencia, semaforos de ENEL SOOmts. al este Apartado Postal #69 Managua, Nicaragua Tel: 505-2783923 Fax: 505-2670106 www.uca.edu.ni (Spanish) Universidad Nacional de Ingenieria (UNI) Campus "Simon Bolivar" Avenida Universitaria, Managua, Nicaragua Campus "Pedro Arauz P.," Costado Sur Villa Progreso Managua, Nicaragua Apartado Postal 5595 Tel: 505-267-0274, 505-249-4287 Fax: 505-267-3709 www.uni.edu.ni (Spanish) Universidad Nacional Agraria (UNA) Km 12 1/2, Carretera Norte Apartado postal No. 453, Managua tel: 505-2331619 fax: 505-2331950 www.una.edu.ni (Spanish) Escuela Agricola Panamericana Zamorano www.zamorano.edu.hn (Spanish and English) Latin American Network Information Center www.lanic.utexas.edu (English) Links to helpful websites in Latin America, by region or country, under the topics of sustainable development, economics, government, media, social sciences and more. Centre Panamericano de Ingenieria Sanitaria y Ciencas del Ambiente (CEPIS) http://www.cepis.ops-oms.org (Spanish and English) Virtual library of information about health, water quality and sanita- tion in Latin America. 9.5 Documents from the Pilot Project Arena That May Be Useful Esteli • "Esteli Municipal Development Plan" (in Spanish). • Basic Information for the Implementation of a Plan for the Rehabilitation, Management and Conservation of Watersheds that are Used for Potable Water Supply in the Departments of Esteli, Madriz and Nueva Segovia." ENACAL, Northern Technical Assistance Unit. • Environmental Rehabilitation Plan - Southern Rio Esteli Watershed. Preliminary Version. National Service of Watershed Management (SENOC), MARENA, the Interinstitutional Commission for the Recuperation and Conservation of the Rio Esteli Watershed (CICRE), and German Social Technical Cooperation Service (DED). • Water Quality Data for Drinking Water Wells in Esteli, Complete Physical Chemical Analysis Performed in Regional Laboratory, Urban Sector, Municipality of Esteli. 1999. ENACAL - Esteli. • Esteli Water Supply Plan showing locations of public water supply wells. Ocotal • Municipal Governments of Dipilto and Ocotal, Nueva Segovia. Process of Improvement of Citizen Participation for Sustainable Development. Intermunicipal Forum of Dipilto, Ecological Situation of the Rio Dipilto. August 19, 1997. • Project Document: A Green Ocotal to the 21st Century. Municipal Government of Ocotal and Community. Forest Management and Reforestation in Ocotal Region. • Map of Barrios in Ocotal. • 1999 Population projection (urban and rural) in Ocotal, by age group and sex. Matagalpa • Proyecto Cuencas Matagalpa. Bulletin. 2000. Matagalpa, Nicaragua. • Proyecto Cuencas Matagalpa. Environmental Education Modules. 2000. Matagalpa, Nicaragua. • Potential Land Use within Two Major Drinking Water Watersheds in Matagalpa • Actual Versus Potential Land Use within Two Major Drinking Water Watersheds in Matagalpa • Soils within Two Major Drinking Water Watersheds in Matagalpa • Potential Evapotranspiration within Two Major Drinking Water Watersheds in Matagalpa • Proposed Forestry and Forest Protection within Two Major Drinking Water Watersheds in Matagalpa • Changes in Land Use for Annual Cultivation and Coffee within Two Major Drinking Water Watersheds in Matagalpa • Hydrologic Conditions within Two Major Drinking Water Watersheds in Matagalpa ------- General • Enlace Special Issue. Special Issue 72, Year 2000. Local stories relating experiences in improving local living conditions and how to better prepare for emergencies such as Hurricane Mitch. • Environmental Education Program. Watershed Restoration, Multiple Water Use, Water Contamination, and Water Resource Conservation. Information and Presentation from Lie. Msc. Manual Silva and Lie. Msc. David Rios O. Ecological consultants in educa tion and environment. • Watershed Protection Pamphlet. GreenCOM El Salvador Project, US AID and the Academy for Educational Development. ------- References Chapter 1 Environmental Protection Agency (EPA), [2001]. Home Page of the United States Environmental Protection Agency. Online: www.epa.gov. National Oceanic and Atmospheric Administration (NOAA), [2001]. Mitch: The Deadliest Atlantic Hurricane Since 1780. NOAA, U.S. Department of Commerce. Online: www. ncdc. noaa.gov/ol/reports/mitch/mitch. html. United States Agency for International Development (US AID), [2001]. Home Page of the United States Agency for International Development, Online: www.aid.gov. Chapter 2 Nicaraguan Aqueduct and Sewer Company (Empresa Nicaraguense de Acueductos y Alcantarillados) (ENACAL) - Esteli, [1999]. Physical chemical lab analysis of drinking water quality. Urban Sector, Municipalidad of Esteli, 1999. Laboratorio Regional. ENACAL U.A.T.N. Control de Calidad de Agua. Environmental Protection Agency (EPA), [1999]. Drinking Water Treatment. EPA 810-F-99-013. December 1999. Environmental Protection Agency (EPA), [2001] a. Disinfection Byproduct Information. US EPA EnviroFacts Warehouse. Online: www.epa.gov/enviro/html/icr/dbp.html (as of June 20, 2001). Environmental Protection Agency (EPA), [2001] b. National Primary Drinking Water Regulations. Online: www.epa.gov/safewater/mcl.html Environmental Protection Agency (EPA), [2001] c. What is a Pesticide? US EPA Office of Pesticide Programs. June 20, 2001. Online: www.epa.gov/opp00001/whatis.htm Environmental Protection Agency (EPA), [2001] d. Why Children May be Especially Sensitive to Pesticides. US EPA Office of Pesticide Programs. February 21, 2001. Online: www.epa.gov/pesticides/food Evans, A.S. and PS. Brachman, [1991]. Bacterial Infections of Humans: Epidemiology and Control. Second Edition. Plenum Medical Book Company, New York. p. 20-23. Gaudy, A.F. and E.T. Gaudy, [1980]. Microbiology for Environmental Scientists and Engineers. McGraw-Hill Book Company, New York. p. 670-685. Madigan, M.T., J.M. Martinko, and J. Parker., [2000]. Brock Biology of Microorganisms. Prentice Hall, Upper Saddle River, NJ. p. 974-975. Ministry of Environment and Natural Resources (Ministerio de Ambiente y Recursos Naturales) (MARENA), [no date]. Manual Sobre Regulaciones de Calidad Ambiental. Direccion general de Calidad Ambiental Asesoria Legal de MARENA. Financiado por PASMA-DANIDA/MARENA. Ministry of Health (Ministerio de Salud) (MINSA), [November 17, 2000]. Personal communication by Horsley & Witten, Inc. with Maritza Obando and Victor Calixto. MINSA, Managua, Nicaragua. Pan American Health Organization (PAHO), [1998]. Health in the Americas, 1998 Edition, Volume II. p. 382-390. Pan American Health Organization (PAHO), [1999]. Nicaragua: Basic Country Health Profiles, Summaries 1999. Online: www.paho.org.english/sha/prflnic.htm. Pan American Health Organization (PAHO), [2001]. Number of cholera cases in the Americas 1991- 2000. Online: www.paho.org/English/HCP/HCT/Cholera_cases_1991-2000.htm. Proyecto Cuencas Matagalpa, MINSA, AYAMAT, and MECD, [1999]. Modulo: Situacion higienico sanitaria en las cuencas Molino Norte y San Francisco y barrios norte de Matagalpa. Matagalpa, Nicaragua. World Health Organization (WHO), [1993]. Guidelines for drinking-water quality, 2nd Edition. Volume 1: Recommendations. Geneva, World Health Organization. Online: http://www.who.int/water_sanitation_health/GDWQ/Chemicals (as of June 20, 2001). World Health Organization (WHO), [1996]. Guidelines for drinking-water quality, 2nd Edition. Volume 2: Health Criteria and Other Supporting Information. Geneva, World Health Organization. Online: http://www.who.int/water_sanitation_health/GDWQ (as of June 20, 2001). Chapter 3 Gleick, Peter H., [1998]. The World's Water: The Biennial Report on Freshwater Resources 1998-1999. Island Press, Washington, D.C. Pan American Health Organization (PAHO), [1998]. Health in the Americas, 1998 Edition. Volume II. World Bank, [2000]. Nicaragua at a Glance. Online: http://www.worldbank.org/data/countrydata/aag/nic_aag.pdf. September 12, 2000. World Bank, [2001]. Nicaragua Poverty Assessment: Challenges and Opportunities for Poverty Reduction. Volume 1: Main Report. World Bank Report No. 20488-NI. February 21, 2001. Manahan, Stanley E., [1994]. Environmental Chemistry. Sixth Edition. Lewis Publishers, Boca Raton, p. 179-188. ------- Chapter 4 Environmental Protection Agency (EPA), [1999]. Tools for Watershed Protection: A Workshop for Local Governments. Prepared by Horsley & Witten, Inc. for US EPA, Office of Wetlands, Oceans and Watersheds. Lander, Charles H., David Moffitt, and Klaus Alt, [1998]. Nutrients Available from Livestock Manure Relative to Crop Growth Requirements. Appendix II: Manure Characteristics. Resource Assessment and Strategic Planning Working Paper 98-1. U.S. Department of Agriculture, Natural Resource Conservation Service. February, 1998. Massachusetts Department of Environmental Protection (MA DEP), [No Date]. Nitrogen Modeling. Prepared by Horsley & Witten, Inc. for the MA DEP, Division of Water Supply. Chapter 5 Charney, Alexandra. August [2000], Prototipo Expendiente de Una Servidumbre Ecologica. Masters Project/Internship for The Nature Conservancy. Ecuador. Mack, Stephen A.J.D. [1997], Las servidumbres ecologicas en America Central - Conservation Easements in Central America. Costa Rica: COMBOS, CEDARENA, The Nature Conservancy. Ministry of Environment and Natural Resources (Ministerio de Ambiente y Recursos Naturales) (MARENA), [no date]. Manual Sobre Regulaciones de Calidad Ambiental. Direccion general de Calidad Ambiental Asesoria Legal de MARENA. Financiado por PASMA-DANIDA/MARENA. Chapter 7 Institute Nicaraguense de Recursos Naturales y el Ambiente (IRENA), [1993]. Plan de Desarrollo de la Cuenca del Rio Dipilto. Servicio Nacional de Ordenamiento de Cuencas (SENOC). February. Managua, Nicaragua. Chapter 8 Kuhl, Mausi., January, [2001]. Personal Communication. January 18, 2001. Matagalpa, Nicaragua. Proyecto Cuencas Matagalpa, [2000]. Bulletin. Matagalpa, Nicaragua. ------- Glossary of Terms Aquifer: A subsurface unit of rock or sediment characterized by formations and/or sediments capable of storing and transmitting water in sufficient quantities to supply pumping wells. Biodigestion: Bacterial breakdown of organic material, such as that found in discharge waters from coffee processing, that produces methane as a byproduct. Compost: A mixture of decaying organic matter used to improve soils and provide nutrients. Conservation Easement: A legal mechanism under which a private landowner relinquishes land use rights to a town, national government, individual or conservation group in exchange for some financial benefit to the land owner. Ground Water: Water beneath the earth's surface. Pesticide: Any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating pests including weeds, insects and fungus. PH test: A measurement of a substance to show whether it is acidic or basic based on the concentration of hydrogen ions present. Recharge: Water, typically from precipitation, that seeps into the ground and reaches a ground water aquifer. Runoff: Precipitation that does not seep into the ground, but flows down slope over the land surface to the nearest surface water body. Source Water Protection Area (SWPA): An area that supplies water to a public water supply, ground water well, or surface water intake. Stakeholders: Any individuals or groups, such as local farmers, trade organizations, government entities, local businesses, and community residents with an interest in the quality of drinking water and management of source water areas. Surface Water: Water occurring at the land surface, including streams, rivers, ponds, lakes, estuaries and the ocean. Uniform Flow Equation: A mathematical equation that can be solved to delineate the down-gradient and lateral limits of a source water protection area for a well. Volumetric Flow Equation: Equation that can be used in the Calculated Fixed Radius method to delineate a source water protection area for a well. Watershed: The land area that contributes water to the mouth of a river or stream, or to a lake. Watershed Area: The land area from which water drains to a point on a receiving body of water. Zone of Contribution: The land area through which recharge occurs and beneath which water flows to a pumping well. ------- Glossary of Acronyms AMCRE: Association of Municipalities of the Esteli River Watershed (Asociacion de Municipios de la Cuenca del Rio Esteli) AYAMAT: Aqueducts and Sewerage of Matagalpa (Acueductos y Alcantarillados de Matagalpa) CFR: Calculated Fixed Radius method, used to delineate a source water protection area for a well. The basic equation used is r = (Q/Rp)l/2, where r = radius of the protection area (feet), Q well pumping rate (cubic feet/year) and R = recharge rate (feet/year). COBEN: High School of Biologists and Ecologists of Nicaragua (Colegio de Biologistas y Ecologistas de Nicaragua) CURN: UNAN University Center of the Northern Region (Centre Universitario de la Region Norte) ENACAL: Nicaraguan Aqueduct and Sewer Company (Empresa Nicaraguense de Acueductos y Alcantarillados) ENACAL-DAR: Rural Areas Division of the Nicaraguan Aqueduct and Sewer Company (Empresa Nicaraguense de Acueductos y Alcantarillados - Division de Areas Rurales) EPA: United States Environmental Protection Agency GIS: Geographic Information System INAFOR: National Forestry Institute (Institute Nacional Forestal) INETER: Nicaraguan Institute of Territorial Studies (Institute Nicaraguense de Estudios Territoriales) MAGFOR: Ministry of Agriculture and Forestry (Ministerio de Agricultura y Forestal) MARENA: Ministry of Environment and Natural Resources (Ministerio de Ambiente y Recursos Naturales) MINSA: Ministry of Health (Ministerio de Salud) PAHO: Pan American Health Organization UNAN: National Autonomous University of Nicaragua (Universidad Nacional Autonoma de Nicaragua) USAID: United States Agency for International Development USDA: United States Department of Agriculture WHO: World Health Organization ------- -------
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https://www.ssa.gov/policy/docs/ssb/v83n1/v83n1p1.html
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# Effects of the Ticket to Work Program: Return on Investment and Overall Assessment of Outcomes Versus Design
by
Social Security Bulletin, Vol. 83 No. 1, 2023
The Ticket to Work (TTW) program was established by 1999 legislation to expand access to vocational rehabilitation services for beneficiaries of Social Security Administration (SSA) disability benefit programs. We evaluate TTW and compare its outcomes with the intentions of its authorizing legislation. We also compare the program's costs with the benefit savings resulting from the reemployment of successful program participants. We analyze unadjusted descriptive statistics, then consider potential participation bias among individuals who received employment services by devising an econometric analysis that accounts for the seriousness of a participant's interest in work. We find that TTW improved employment outcomes and generated net benefit savings to SSA for many employment-service clients, but the savings did not fully offset program costs. However, these estimates should be regarded as lower bounds of TTW's positive effects because they do not account for higher service needs of TTW program participants.
Paul O'Leary is an economist with the Office of Retirement and Disability Policy, Social Security Administration. Emily Roessel is a senior policy researcher with the Social Security Advisory Board.
Acknowledgments: The authors thank Mark Trapani for his particularly insightful guidance on early drafts of this manuscript as well as helpful comments on the final draft. We also thank Kai Filion, Jackson Costa, David Weaver, Robert Weathers, and Jeffrey Hemmeter for useful feedback and suggestions.
The findings and conclusions presented in the Bulletin are those of the authors and do not necessarily represent the views of the Social Security Administration.
## Introduction
BFW benefits forgone for work CDR continuing disability review DAF Disability Analysis File DI Disability Insurance EN employment network GAO Government Accountability Office OLS ordinary least square SGA substantial gainful activity SSA Social Security Administration SSI Supplemental Security Income STW (benefits) suspended or terminated because of work SVRA state vocational rehabilitation agency TPM Ticket Program Manager TTW Ticket to Work TWP trial work period VR vocational rehabilitation
The Social Security Administration (SSA) has operated the Ticket to Work (TTW) program for 2 decades. TTW aims to enable SSA disability program beneficiaries to exit the program rolls and attain self-sufficiency through work by facilitating their access to and participation in employment training and support services. Many policymakers had high hopes for TTW when it was established and, for some, the program's results have been disappointing. This analysis examines the program's intentions, as described in the Ticket to Work and Work Incentives Improvement Act of 1999, and its outcomes through 2016. It also compares the program's costs with the benefit payments forgone for the beneficiaries the program served as intended.
TTW was based on the premise that many Supplemental Security Income (SSI) and Social Security Disability Insurance (DI) beneficiaries had the functional capacity and the desire to work but had too few options for employment services. Before TTW, all such services were provided by entities called state vocational rehabilitation agencies (SVRAs). It was thought that because SVRAs faced no competition for SSA disability program clients and received payments from SSA under a cost-reimbursement model, the existing vocational rehabilitation (VR) system did not give SVRAs incentives to provide the innovative solutions that could enable more of their clients to discontinue cash benefits through long-term employment. A Disability Policy Panel convened by the National Academy of Social Insurance in 1993 envisioned an expansion of employment service availability and choice by allowing public and private service providers, which would come to be known as employment networks (ENs), to compete with SVRAs for clientele. The panel also conceived a performance-based model for SSA payments to the service providers (Mashaw and Reno 1996). The existing payment system, entailing reimbursement for costs associated with providing employment services, would remain available; but providers would now have the option of receiving payments based on their clients' performance-based milestones and outcomes. A key feature of the new system would be the direct linkage of provider payments to beneficiary progress toward employment success and the resulting reductions in benefit payments. In this way, the program attempted to align the incentives of the employment service providers with those of SSA and the beneficiaries attempting to exit the disability rolls and achieve financial independence via work (Stapleton and Livermore 2003; Huynh and O'Leary 2003).
The Ticket to Work and Work Incentives Improvement Act, Public Law 106-170, was signed into law on December 17, 1999. A centerpiece of the act was the Ticket to Work and Self-Sufficiency Program, which was meant to comprehensively address longstanding issues that were seen as limiting employment for beneficiaries with disabilities. TTW created the new class of service providers, ENs, that the Disability Policy Panel had envisioned, and established the rules that aligned the SSA provider payments they received with the long-term success of beneficiaries. The legislation also protected beneficiaries from continuing disability reviews (CDRs, which affirm or deny ongoing eligibility for benefits) while they participated in TTW,1 extended access to Medicare or Medicaid coverage for beneficiaries returning to work, and allowed for expedited benefit reinstatement if the work attempt ultimately failed. As the Ticket to Work and Work Incentives Advisory Panel noted in their final report (2007), the act “represented the culmination of efforts by diverse stakeholders who recognized the importance of removing barriers to employment and labor market activity for individuals with disabilities.” The panel further noted that the legislation “demonstrated the evolution of thinking and attitudes about the interest in and capacity of people with disabilities to work, contribute to our nation's economy, and reduce their reliance on public benefits.” Radtke (2000) described the act as “one of the most significant changes in disability policy in the last 20 years.”
Despite early optimism, as the program unfolded and the results of SSA's evaluations were released, many came to regard TTW as a failure (Butler 2018; Government Accountability Office [GAO] 2011; Khazan 2015; Lankford 2017; Lawler 2014; SSA 2008). Eimicke, Cohen, and Miller (2017) noted that “by December 2005…a mere 1.8% of disability beneficiaries were participating in the TTW program in the 13 Phase 1 states” and that “as of early 2007, ENs as well as SVRAs were losing interest in the program.” Autor and Duggan (2010) described the TTW program as “ineffective” and noted that “fewer than 1,400 tickets (0.01 percent) of 12.2 million tickets issued in the first seven years of the…program led to successful workforce integration.”
It seems clear that the TTW program has not achieved the lofty changes many had anticipated for it. It is less clear, however, whether one should regard the program as a failure. Improving the rate at which beneficiaries leave the disability program rolls and become self-sufficient was an obvious goal of the program, but it was not the only goal, and one should consider all of TTW's objectives in assessing its level of success. That is a complex undertaking, as measures of program success are open to interpretation. SSA hired an independent contractor to evaluate TTW, which produced extensive findings on TTW activities, outcomes, and effects. In seven reports,2 the evaluation delves into topics ranging from SSA's implementation of TTW, participation by ENs and beneficiaries, the effect of regulatory changes implemented in 2008, crossover effects between SVRAs and ENs, program costs, and outcomes involving work attempts, earnings, and disability benefit receipt. Although the reports describe successes, failures, and adjustments, SSA did not design the evaluation to reach a single conclusion on TTW. Instead, the agency intended the evaluation to provide detailed findings on the various program aspects to inform decision makers and the public. As such, readers can reach a variety of conclusions from the reports.
To provide an overall TTW program assessment, we examine two basic research questions: Does the program achieve the stated objectives of its authorizing legislation, and has it produced benefits that exceed its costs? Although these questions are conceptually simple, overall costs and benefits can be difficult to measure.
The analysis is structured as follows. We start with an overview of expectations for the TTW program as outlined in the legislation that created it. We then review the findings from the TTW evaluation in the context of the legislative goals. We then extend those findings in two ways. First, we analyze service delivery, program costs, and employment and benefit outcomes without regard to what would have happened in the absence of TTW. Second, we assess employment outcomes using multivariate regressions, focusing on DI beneficiaries who have completed a trial work period (TWP)—during which a beneficiary can accrue earnings without risking benefit termination, under program rules—as a means of addressing selection bias among those who choose to use TTW services.
## Overview of TTW Expectations and Perceived Results
The text of Public Law 106-170 stated that the primary purpose of TTW was
to establish a return to work ticket program that will allow individuals with disabilities to seek the services necessary to obtain and retain employment and reduce their dependency on cash benefit programs.
Subsequent passages, designated as “findings” 1 and 10–12 of the law's text, suggested additional goals of the program:
(1) It is the policy of the United States to provide assistance to individuals with disabilities to lead productive work lives.
(10) Eliminating…barriers to work by creating financial incentives to work and by providing individuals with disabilities real choice in obtaining the services and technology they need to find, enter, and maintain employment can greatly improve their short and long-term financial independence and personal well-being.
(11) In addition to the enormous advantages [this law's] changes promise for individuals with disabilities, redesigning government programs to help individuals with disabilities return to work may result in significant savings and extend the life of the Social Security Disability Insurance Trust Fund.
(12) If only an additional one-half of one percent of the current Social Security Disability Insurance and Supplemental Security Income recipients were to cease receiving benefits as a result of employment, the savings to the Social Security Trust Funds and to the Treasury in cash assistance would total $3,500,000,000 over the worklife of such individuals, far exceeding the cost of providing incentives and services needed to assist them in entering work and achieving financial independence to the best of their abilities. Thus, although the primary goal to TTW was to reduce benefit payments by significantly increasing the rate at which benefits can be suspended or terminated because of work (STW), the act clearly included at least three other, though arguably secondary, objectives: 1. Expand the services available to and used by beneficiaries that might allow them to obtain and retain employment. 2. Improve the lives of beneficiaries by enabling greater self-sufficiency, with increased earnings allowing the reduction or elimination of dependence on cash benefits. 3. Bring about benefit reductions in amounts that exceed the cost SSA pays to providers for employment services. Since the completion of the TTW evaluation in 2013, stakeholders have tended to focus on the finding that the program has not made significant progress toward the primary goal of reducing the disability rolls. Less attention has been paid to the substantial evidence, presented below, that TTW has (1) expanded the range of services available to beneficiaries, (2) had a positive effect on participants, and (3) done so with costs that are no higher than those for the SVRA-only services it replaced, and are potentially lower than the benefit reductions that have ensued. ## TTW Effects on Benefit Receipt As noted above, SSA funded a comprehensive TTW evaluation, as required in the authorizing legislation. SSA contracted with the Lewin Group in 2000 to design the TTW evaluation, and with Mathematica (then known as Mathematica Policy Research) in 2002 to implement the evaluation. SSA also contracted with Mathematica in 2003 to conduct a survey to collect information needed for the evaluation that was not available in agency administrative data. Mathematica conducted the survey in four rounds from 2004 through 2010, collecting information from more than 20,000 beneficiary respondents. The evaluation spanned 11 years and produced seven reports, each comprising from one to nine separately published studies, and several policy briefs. The fourth evaluation report (Stapleton and others 2008) and a study from the seventh report (Stapleton, Mamun, and Page 2013) specifically addressed TTW's net effect on the size of SSA's disability beneficiary population. If that outcome is measured by the rate at which TTW enabled DI disabled-worker beneficiaries to resume work at an earnings level that constitutes substantial gainful activity (SGA)—and thereby allows them to forgo cash benefits—then Table 1 appears to show that TTW had little or no effect.3 Although the benefit termination rates for SGA were marginally lower than 0.55 percent in years after 2001, the last full year before TTW Phase 1 implementation, the rates varied little. However, this simple measure does not account for differences over time in the beneficiary population or other environmental factors. The results in Table 1 are generally regarded as “gross outcomes,” as they do not attempt to account for related factors that could accentuate or offset any TTW effects. Results of analyses that attempt to remove or “net out” these related factors are generally regarded as “net effects.” To account for these other factors, more sophisticated statistical methods are needed. The evaluation contractor therefore attempted to measure the net increase in the rate at which beneficiaries reduced their dependence on disability benefits that was specifically attributable to the TTW program. Stapleton and others (2008) reported the results of the first of these analyses, and Stapleton, Mamun, and Page (2013) revised and updated those results using improved analytical techniques and additional data. The findings of these two analyses were consistent, and because the 2013 analysis was more robust, we focus on that latter report here. Table 1. DI disabled-worker beneficiaries: Total and with benefits terminated because of SGA-level work, 2001–2016 Year Total With benefits terminated because of SGA Number Percent 2001 5,268,039 29,000 0.55 2002 5,539,597 29,165 0.53 2003 5,868,541 27,926 0.48 2004 6,197,385 28,613 0.46 2005 6,519,001 36,263 0.56 2006 6,806,918 36,242 0.53 2007 7,098,723 33,381 0.47 2008 7,426,691 37,711 0.51 2009 7,788,013 32,445 0.42 2010 8,203,951 40,959 0.50 2011 8,575,544 39,813 0.46 2012 8,826,591 38,228 0.43 2013 8,940,950 31,591 0.35 2014 8,954,518 35,846 0.40 2015 8,909,430 39,652 0.45 2016 8,808,736 47,887 0.54 SOURCES: SSA, Annual Statistical Report on the Social Security Disability Insurance Program, 2001–2016 editions, Tables 1 and 50. SSA implemented TTW in three phases, each encompassing a different group of states, from the beginning of 2002 through the end of 2004. The 9/11 attacks disrupted the Phase 1 rollout in New York, leaving only Phases 2 and 3 as viable for analysis. In each phase, SSA divided randomly selected beneficiaries into 10 “mail-month” groups. SSA mailed tickets, which program participants could exchange for employment services with an SVRA or an EN, to the first group in November of that phase's year, sent no tickets in December, and sent tickets to one of the remaining groups each month from January through September of the next year. Thus, a random subset of beneficiaries in each phase got their tickets as much as 11 months sooner than those in the latter mail-month groups. Stapleton, Mamun, and Page (2013) used this randomness to estimate the difference in TTW effects between the early and late mailing groups.4 However, because all mail-month groups in each phase received tickets within an 11-month span, the period available for measuring TTW effects was limited, which in turn limited the precision of this evaluation method. Both the 2008 and 2013 analyses concluded that TTW had generated a statistically significant net increase in employment service enrollment with both ENs and SVRAs, but it did not increase, at statistically significant levels, the proportion of beneficiaries with disabilities who were able to transition from cash benefits to STW status—that is, to self-sufficiency. In particular, the evaluators found evidence that receiving a ticket 11 months sooner than other beneficiaries in Phase 2 increased the attainment of STW status by 7 percent, and the number of months in STW status by 5 percent, as of 48 months after the phase began. However, for Phase 3, the evaluators found no significant effect on STW status, and the effect on the number of STW-status months was similar to that for Phase 2 but in the opposite direction. They also found that TTW's effects on the completion of TWP months were insignificant for Phase 2, which cast further doubt on the positive Phase 2 STW-status findings because improved STW-status outcomes should be associated with improved TWP outcomes, as the latter is a precursor to the former. The evaluators concluded that the effects they measured were effectively random and therefore not statistically different from zero. Although the evaluators' finding was disappointing, two points are worth considering. First, Congress designed the TTW program to supplement the cost reimbursement system that SSA had used for SVRAs since 1981. Under that system, SVRAs were reimbursed if a client attained an earning objective, with or without reaching STW status. TTW added ENs as eligible service providers and allowed ENs and SVRAs to choose whether to be reimbursed under the traditional system or under one of two alternatives: either a “milestone plus outcome” or an “outcome only” system, which tied payments to the client's STW status in the current month. Following standard practice, the evaluator analyzed the TTW's effects relative to the prior system. In other words, the net effect of TTW was the difference between the combination of EN and SVRA services and SVRA services alone, the services which had been available prior to TTW. The evaluation did not, and could not, measure the effect of TTW by comparing outcomes for beneficiaries receiving services from an SVRA or an EN to outcomes for beneficiaries who had no access to services. The TTW evaluation did not attempt to measure the effect of employment services on the beneficiaries who used them, but other studies have, albeit with several limitations. For example, Dean, Dolan, and Schmidt (1999) and Dean and others (2001, 2014) used the earnings of SVRA clients to measure success, and compared annual earnings to service costs to assess their performance. Those studies found that beneficiaries generally increase employment and earnings after receiving SVRA services and that their earnings exceed the cost of services.5 Earnings relative to service costs, however, tell us little about effectiveness relative to disability benefit receipt. One analysis of earnings relative to SGA found that such earnings are not sufficient to discontinue disability benefits (GAO 2007). However, because SVRA-provided supports represent an ongoing national program, it is not possible to use an experimental design to study their effects. Researchers are thus left with only quasiexperimental methods that compare participants with characteristically similar nonparticipants such as VR service dropouts. Whether the comparison groups have been similar enough to participants to address the inherent selection bias implicit in completing VR services is unclear and this limits the strength of the findings in these studies. We will discuss selection bias in more detail later. Second, the evaluation notably did not estimate TTW effects on participants only. By necessity, Mathematica evaluated TTW's effects on all beneficiaries (this is known as the “intent-to-treat” approach in the economic literature). Because TTW serves a relatively small proportion of DI beneficiaries and SSI recipients with disabilities, and many such beneficiaries and recipients forgo benefits for work without using employment services, TTW's effects on participants would need to be substantial to have a measurable effect on the larger population of beneficiaries and recipients. Mathematica did not find a large effect, but a small positive effect would have been undetectable because of the limitations of the methods available. Both evaluation-design elements—the assessment of TTW effects relative to the prior system and the use of intent-to-treat methodology—made sense, given the way Congress required SSA to roll TTW out and the program's main goal of substantially increasing exits from the disability benefit rolls. However, these design parameters limited the methods available to the evaluator, and those methods limit the implications of the results. We know that TTW did not lead to a large increase in disability benefit exits, but we do not know if smaller effects were achieved. In fact, Stapleton, Mamun, and Page (2013) found that “the statistical power of the projections for STW [status] and the number of STW [status] months is insufficient to rule out the possibility that TTW had impacts of at least five percent on each outcome for Phases 2 and 3 pooled.” More precisely, their analysis found that TTW increased STW status incidence by less than 30 percent and the number of months in STW status by less than 9 percent, but they could not rule out smaller effects that approached those boundaries. This is not to say that the evaluation found evidence that positive outcomes occurred. Instead, we merely note that, given the inherent limitations of the evaluation methodology, effects of less than these magnitudes could have occurred without statistically significant detection. The methodological restrictions simply prevented a more precise result. The evaluation also could not assess TTW's effect on other outcomes of interest. In particular, it did not address whether EN and SVRA services significantly increased employment among participants. Because employment by itself does not directly affect benefit eligibility, SSA does not track employment data. SSA tracks earnings, but only if they are high enough to affect benefits. Further, pre- and post-TTW earnings data are inconsistent because the quality of the earnings tracking changed after TTW implementation, as the program required SSA to improve its earnings data to calculate EN payments accurately. As such, the earnings and employment data for disability program beneficiaries that would allow a comprehensive TTW assessment are in some instances unavailable, or are available with gaps, especially for the pre-TTW comparison period. These limitations were not flaws of the evaluation design. Rather they reflect what was possible given the information available to the evaluator, the characteristics of the TTW program, and the way Congress required SSA to implement it. Even the finding that TTW did not greatly affect the disability roll exit rate is more complicated than it first appears. The evaluation found that the success rate that resulted from combining EN and SVRA services was statistically no different from offering only SVRA services. To the extent that SVRA services had been effective prior to TTW, they continued to have a similar level of success after TTW, and the success rates for ENs were similar to the SVRA results. In fact, the success rate was higher for ENs, meaning that the new ENs were at least as effective as SVRAs. This does not necessarily mean, however, that ENs are better at serving beneficiaries than SVRAs. Because ENs can choose their clients while SVRAs cannot, adding ENs to the service mix under TTW may have simply shifted some of the easier-to-serve cases from SVRAs to ENs.6 Regardless, combined EN and SVRA services reach the same level of success that SVRAs alone had previously achieved. We explore this finding in further detail later. ## Other Effects of TTW As noted earlier, increasing the rate at which beneficiaries leave the disability rolls for work and thereby lower the amount of cash benefits paid by SSA was not TTW's only objective. Other objectives included expanding the availability and use of employment services, increasing the self-sufficiency of people with disabilities through expanded earnings, and spending less on employment services than the dollar value of benefits that would be paid if beneficiaries remained on the rolls. TTW clearly increased consumer choice for beneficiaries. Further, under TTW, SVRAs could choose, case by case, whether to serve a client under either the existing cost reimbursement model or one of the new TTW payment options—in the latter cases, operating essentially as ENs. In addition to these SVRAs operating under both the new and old payment rules, approximately 600 ENs joined the ranks of employment service providers under TTW.7 Many of those ENs were VR vendors that had provided services under contract with SVRAs, but others offered new service models. These included “consumer-directed service ENs, which share a portion of the TTW payments they receive with their clients; employer ENs receiving TTW payments based on work activity of their TTW participant employees; [and] state workforce agency ENs comprising local workforce investment boards and One-Stop Career Centers” (Schimmel and others 2013). Beneficiaries have responded to the expanded choice by using EN services at an increasing rate since they were first offered, and this increase in choice also likely contributed to some of the increase in participation in return-to-work services that Mathematica found. Using data from SSA's Disability Analysis File (DAF), Chart 1 shows that although SVRAs have dominated the TTW ticket assignments, EN assignments have risen steadily since that option was fully implemented in 2005.8 Although SVRAs received 93 percent of ticket assignments in 2005, their market share had dropped to 72 percent by 2019. Further, while the numbers of tickets assigned to SVRAs have remained relatively constant since 2012 (with slight declines since 2015), EN assignments have increased by 80 percent since 2012, indicating progress toward Congress' intent of expanding service alternatives. Show as table Table equivalent for Chart 1. TTW participation: Tickets assigned, by provider type, 2005–2019 (in thousands) Year ENs SVRAs (adjusted) SVRAs (unadjusted) 2005 4.769 66.172 63.583 2006 4.581 71.490 66.312 2007 4.522 77.710 69.944 2008 10.646 88.770 78.415 2009 14.748 93.707 80.763 2010 19.121 104.676 89.143 2011 18.998 107.234 159.010 2012 17.424 97.133 97.133 2013 22.519 87.032 . . . 2014 18.809 98.972 . . . 2015 18.742 106.992 . . . 2016 21.284 104.453 . . . 2017 24.022 100.014 . . . 2018 28.024 91.193 . . . 2019 30.679 90.934 . . . 2020 17.704 44.448 . . . SOURCE: Authors' calculations based on 2020 DAF. NOTE: SSA instituted stricter reporting requirements for SVRAs in 2011. The adjusted figures for SVRAs smooth the spike in “catch-up” assignments reported for 2011 by estimating likely annual flows had the reporting requirements been in place from 2005 forward. . . . = not applicable. Mathematica also found that TTW increased the level of interest in work among disability program beneficiaries. The National Beneficiary Survey (NBS), sponsored by SSA and conducted by Mathematica, includes questions that probe beneficiaries' expectations about future employment. Comparing results from the first NBS in 2004 (Thornton and others 2006) with those from the round completed in 2015 (SSA 2018a) shows an increase in beneficiary interest in substantial work across multiple measures: • Goals include work or career advancement (from 30 percent to 37 percent); • Sees oneself working for pay • in the next 2 years (from 20 percent to 25 percent) • in the next 5 years (from 26 percent to 28 percent); • Sees oneself working and earning enough to stop receiving disability benefits • in the next 2 years (from 7 percent to 11 percent) • in the next 5 years (from 15 percent to 17 percent).9 This increase in interest in work is consistent with the net increase in participation in employment services noted above. Stapleton, Mamun, and Page (2013) found that employment service enrollment increased by about 15 percent over the 48-month observation period in the Phase 2 and Phase 3 states. Increases in reported interest in work and in employment service participation would seem to be a significant positive result, even without increases in disability roll exits. Congress intended TTW, at least partly, to improve opportunities for disability program beneficiaries and to change expectations about work, so it seems reasonable to regard higher interest in work and employment service participation as TTW successes. Not all of the additional participants assigned their tickets to ENs: They distributed their tickets among both provider types, and the TTW evaluations found differences between participants who sought EN services and those who sought SVRA services (Thornton and others 2006; Stapleton and others 2008). For example, Stapleton and others found that participants were more likely to assign their Ticket to an EN if they had low benefits, were African American, had minor children, or had been on the rolls for a year or less. Those with [intellectual disability, with] sensory or other nervous system disorders, [with] severe mental health problems, or in need of assistance to perform a daily activity were more likely to assign their Ticket to an SVRA than to an EN. Thus, TTW likely led a broader range of beneficiaries to attempt employment and gave them greater chances of finding services that fit their situations. This, combined with the overall increase in employment service use, suggests that TTW prompted certain beneficiary groups to consider work and to pursue employment goals in greater numbers.10 The fact that participation increased without an increase in the proportion reaching STW status implies that these new participants were less successful overall than those who had participated before TTW implementation. This suggests that TTW broadened the range of beneficiaries interested in work, drawing participants from groups facing marginally greater challenges to work than those who had received SVRA services prior to TTW. These additional participants from the margin likely had less success than other beneficiaries. Moreover, even if we saw no increase in STW status for these beneficiaries, they may have improved their self-worth by attaining some level of work and likely improved their quality of life by adding some earnings to their benefit income. Livermore, Hoffman, and Bardos (2012) found that most TTW participants were satisfied with the services they received during the program's early rollout. About 60 percent of EN users considered themselves “very” or “somewhat” satisfied with those services. Satisfaction was higher for SVRA clients, at about 70 percent. Regression-adjusted satisfaction results improved for both EN and SVRA users after SSA implemented modified TTW regulations in 2008, although only the increase for ENs was statistically significant, at 36 percent.11 Each year, many SVRAs do not have enough resources to serve all their applicants. When that occurs, those SVRAs enter “order of selection” status, wherein they must ration services and prioritize individuals with the most significant disabilities.12 SVRA clients include individuals who are not beneficiaries of SSA programs; and although SSA program beneficiaries tend to have the most significant disabilities among SVRA applicants, they do not constitute all the clients who are prioritized under orders of selection (Honeycutt and Stapleton 2013). Thus, by adding ENs as service providers, TTW has helped to expand the availability of employment services for beneficiaries despite tight fiscal resources among SVRAs. Without ENs, either SVRAs would need to increase the level of services they provide to absorb the demand currently fulfilled by ENs or unmet demand for employment support services would increase. Although TTW has not significantly increased the number of beneficiaries who reach self-sufficiency relative to an SVRA-only system, it has increased the overall availability of employment services, consumer choice, and beneficiary participation, and beneficiaries are generally satisfied with the services they receive through TTW. ## Measuring TTW Costs and Benefits Assessing whether TTW's net effects were “substantial” is a matter of interpretation. The most policy-relevant question is whether TTW provided benefit savings (and other effects) sufficient to offset program costs. TTW participants represent a relatively small proportion of disability beneficiaries. As a result, Thornton (2012) estimated that relatively modest program effects, on the order of a net increase of 2,000 to 3,000 disability roll exits, would be sufficient to offset the costs of the TTW program. Unfortunately, measuring such a small effect was precluded by the evaluation's limited precision: The fact that we did not find statistically significant impacts on STW [incidence or months in STW status] does not by itself rule out the possibility that TTW under the initial regulations had impacts on these outcomes that were sufficiently large for the program to be “self-financing”—that is, for savings from a net reduction in benefits to be sufficient to pay for TTW payments to providers and all administrative costs attributed to the program. Thornton (2012) suggests that only a very small impact—an increase of 3,000 or so in the number of all beneficiaries experiencing STW [status] for the first time in each year—might be sufficient for the program to be self-financing. An annual impact on first-time [STW incidence] that is as small as 3,000 might correspond to such a small impact on STW [incidence] as of month 48 for new, young [DI] beneficiaries that the evaluation would be unable to differentiate between that impact and no impact at all (Stapleton, Mamun, and Page 2013). Stapleton, Mamun, and Page estimated that 3,000 new instances of STW status in 2007 as a result of TTW would have represented a 5 percent increase in those cases. This leaves us with a rather ambiguous evaluation result. We know that the program did not lead to large-scale changes—TTW increased STW incidence by less than 30 percent and it increased the number of months in STW status by less than 9 percent—but we cannot rule out the possibility that it had effects that were of policy relevance. An increase as modest as 5 percent in DI and SSI exits would be sufficient to cover the cost of the program, but we cannot tell if such a change occurred. We can look at cost in the broader sense as well. Because the employment service participation rate increased without a corresponding increase in the rate of disability roll exits, we would expect that the cost of providing such services rose. This in fact took place, but not necessarily because EN services were, on average, more costly. As we detail in Appendix A, ENs and SVRAs have different cost structures related to their different client populations, and this complicates the comparison of costs between the two provider types. Thornton (2012) found that the total provider payments per STW case were notably lower for ENs than for SVRAs. He estimated that SSA-financed return-to-work assistance per STW case was$11,500 (in 2009 dollars) for ENs and $14,035 for SVRAs.13 “The$2,535 difference represents the savings SSA receives when it pays for exits under the new TTW system, which makes outcome payments only while beneficiaries remain off of cash benefits, rather than under the traditional payment system” (Thornton 2012, 40). This result should be viewed with caution as it defines costs narrowly for both ENs and SVRAs, but it does suggest that costs could be higher if SSA reverted to an SVRA-only system and SVRAs served all beneficiaries currently receiving services through ENs.14
Even under Thornton's narrow definition of costs, the actual increase in SVRA costs relative to those for ENs would likely be less than the $2,500 per STW case noted above because the lower EN costs partly reflect the ability of ENs to choose to serve only lower-cost beneficiaries. If those beneficiaries used SVRAs, they would likely generate lower costs and SSA reimbursements, bringing down the average SVRA cost per STW case. Still, as we describe in Appendix A, it seems safe to conclude that TTW has expanded service availability without increasing costs over what would be required to serve the same number of beneficiaries under an SVRA-only system. ### Comparison of TTW Costs and Benefits Regardless of whether TTW expanded service availability and use or changed net disability benefit receipt, we would like to know whether TTW services are effective and provide efficient results for participating beneficiaries. In other words, did TTW services decrease SSA benefit payments relative to what participants would have received in the absence of those services, and were the costs of TTW services less than the net reductions in benefits? Stapleton, Mamun, and Page (2013) focused on whether TTW changed the rate at which disability program beneficiaries return to work relative to the SVRA-only system that preceded it. Their study did not assess whether either the SVRA or EN components of TTW led to reduced benefit payments relative to no services. This is an important distinction. We showed above that TTW expanded service delivery and had the same success as the SVRA-only program that preceded it. We now address whether services provided through SVRAs or ENs under TTW reduce reliance on cash benefits. This is a crucial question, as nothing is gained in expanding an ineffectual program. Although TTW subsumed the national SVRA services program for SSA program beneficiaries with disabilities, many aspects of SVRA and EN services remain separate. We therefore explore the costs and benefits of these two provider types separately, assess their efficiencies, and compare their results. To estimate the beneficial effects of TTW, we focus on the reductions in disability benefits that have resulted from participation. Ideally, we would estimate reductions in disability benefits that have been adjusted to account for the counterfactual: what would have happened if neither EN nor SVRA services were available under TTW. As noted in our discussion of the 2008 and 2013 evaluation reports, however, the methods available for estimating these effects have shortcomings. We therefore start by estimating gross benefit reductions without considering the counterfactual. Because gross benefit reductions are essentially an upper-bound estimate of TTW effects, they can be compared with costs to get a sense of whether net benefits exist at all. If costs are greater than any associated reductions in benefit payments, the program cannot pay for itself. Conversely, if the magnitude of benefit reductions grows relative to program costs, the opportunity for actual savings increases. So, although the outcome analysis cannot definitively show whether TTW provides savings, it can compare program costs to the benefits forgone for work (BFW) to provide an upper bound on TTW effects and thus set context for analyzing whether TTW may offset all or most of its costs.15 ### TTW Costs The two components of TTW program-related expenses are the administrative cost of running the program and the SSA provider payments to ENs and SVRAs. Agency administrative data closely track the provider payments as part of managing the program. SSA's Office of the Inspector General reports these amounts by the year when the payments occur (SSA 2018b). This accounting method has problems because it is affected by budgetary and administrative priorities that are not directly relevant to TTW operations. Reporting cost by date of disbursement tends to show lower payment levels in years when staffing for SSA payment processing was tight, followed by higher payment levels in subsequent years as processing catches up with backlogs. Recording payments by the dates when they are due—when the service provider completes the documentation that supports that payment—would better represent the timing of the beneficiary's work activity that triggered the payment. Table 2 shows the number and value of payments made to employment service providers from 2002 through 2016.16 The numbers of payments under the new TTW systems prior to 2006 were much lower than traditional-system reimbursements as SSA phased in the new program. The low figures in the early years also reflect the lag between the start of EN services and the point at which participants began working at a level sufficient to initiate a payment for the service provider. Payment frequencies under the TTW systems picked up starting in 2006 and then rose significantly after 2008 when SSA implemented new TTW regulations. In the later years, providers using the new milestone- and outcome-oriented payment systems established by TTW received far greater numbers of payments than did SVRAs using the traditional reimbursement model. This reflects the nature of the two payment structures, wherein traditional reimbursement is essentially a “lump-sum” payment after service completion while multiple payments under the newer TTW systems occur over time as beneficiaries reach employment milestones. By 2016, total annual new TTW-system payment amounts had risen to more than$63 million. Yet because the new TTW-system payment amounts are relatively small on average, their total value each year is still lower than that of traditional-system reimbursements. Payment amounts under the traditional system have averaged around $125 million annually, although payments in 2003, 2010, and 2011 were noticeably lower, likely because those years were affected by recessions. All payments under the traditional system went to SVRAs; most of the payments under the TTW's new systems went to ENs, but about 20 percent went to SVRAs (not shown). Table 2. Annual TTW payments to employment service providers, by payment system, 2002–2016 Year of work activity Traditional reimbursement system (SVRAs only) New TTW payment systems (ENs and SVRAs) Number Amount (2016$) Number Amount (2016 $) Total Average Total Average 2002 8,732 148,808,101 17,042 619 237,580 384 2003 5,882 92,822,208 15,781 2,785 1,194,173 429 2004 6,297 101,406,129 16,104 5,831 2,562,568 439 2005 7,510 110,149,079 14,667 8,366 3,535,649 423 2006 6,784 104,411,154 15,391 11,265 4,551,720 404 2007 8,329 125,976,989 15,125 13,642 5,528,360 405 2008 9,761 143,962,909 14,749 25,416 16,939,049 666 2009 8,755 134,450,407 15,357 36,576 26,202,851 716 2010 5,807 90,124,147 15,520 40,730 29,584,050 726 2011 5,255 84,098,895 16,004 46,766 33,029,082 706 2012 7,138 104,086,930 14,582 51,422 35,280,750 686 2013 9,385 135,296,335 14,416 62,839 43,739,871 696 2014 11,137 160,042,350 14,370 76,098 52,458,226 689 2015 12,482 184,826,959 14,807 92,408 62,857,333 680 2016 a 15,687 a 199,507,673 a 12,718 96,897 63,088,995 651 SOURCE: 2016 DAF. NOTE: Annual payment calculations based on the payment-triggering month for ENs and the last date of continuous SGA in the payment claim for SVRAs. a. Estimated based on 11,765 actual payments for$149,630,755 in the first 3 quarters of 2016.
Table 2 includes an interesting dynamic in that the total payment amounts for the new TTW systems relative to the traditional system climbed steadily over time, growing from nearly nothing in 2002 to nearly 40 percent in 2011. Since 2011, TTW-system payment amounts have apparently settled at about one-third the amount of traditional-system payments, although differences in payment lag times between the systems might skew the proportions for 2015 and 2016. By 2015, total provider payments had reached about 250 million, with indications that they would continue to rise. In addition to the payment costs to providers, SSA has incurred administrative costs to run TTW. Some of these costs can be viewed as the continuation of the SVRA administrative costs that existed before TTW subsumed the old system. TTW was not funded under a separate appropriation so there is no line item in the budget that can be used to cite TTW administrative costs. Because there also is no administrative need to track TTW costs separately from those for related functions, SSA does not do so. Still, stakeholders overseeing TTW have expressed interest in quantifying those costs. In response, we used SSA data on staffing levels and estimated the hours spent on TTW-related tasks to compute TTW administrative costs for 2017 in an unpublished SSA report (O'Leary and Roessel 2018).17 For this analysis, we adjust those 2017 cost estimates to 2016 dollars so that they align with our data on EN and SVRA provider payments. The absence of TTW cost estimates for all program years poses alignment issues for this cost-benefit analysis, which covers TTW operations and beneficiary participation beginning in 2006. We make the simplifying assumption that the administrative costs that occurred in 2006 are the only administrative costs for this cohort.18 Ideally, 2006 costs would have been estimated shortly after the close of 2006 and then adjusted to 2016 dollars for this analysis, but no such estimates are available, and recall issues would make new estimates for that year unreliable. Instead, we use the 2017 cost estimate, adjusted to 2016 dollars, which implicitly assumes that annual TTW administrative costs have been flat since 2006. This poses a limitation, which we discuss further below. In this analysis, the TTW administrative cost estimates account only for SSA staffing, printing, mailing, and contract resources specifically dedicated to the TTW program. Costs are separately calculated for operations related to EN and SVRA ticket assignments. Staffing costs include those for headquarters, regional office, and field office personnel and are based on workload assessments for a representative sample of staff. The administrative cost estimates do not include costs for activities not specifically related to the TTW program. They also do not include any costs for information systems except those managed by the Ticket Program Manager (TPM) under the TPM contract. Further, they exclude any costs associated with beneficiaries who remain on the rolls because SSA did not conduct a CDR, under the TTW provision protecting participating beneficiaries from undergoing one (which might lead to benefit cessation).19 Finally, we also exclude any potential excess costs of unrecovered overpayments for TTW participants and associated administrative costs.20 We estimate total TTW administrative costs for 2016 of18.8 million, of which $12.3 million were for operations related to EN ticket assignments and$6.5 million were related to SVRA assignments (Table 3). Based on the 2016 figures from Tables 2 and 3, the administrative costs related to SVRA ticket assignments under the traditional payment system represent about 3 percent of total costs of operating that part of the program ($6.5 million ÷ [$199.5 million + $6.5 million]), and administrative costs related to EN assignments under the TTW payment systems represent about 16 percent of total costs of operating that part of the program ($12.3 million ÷ [$63.1 million +$12.3 million]). Notably, the costs related to SVRA assignments do not account for the substantial SVRA funding provided by non-SSA federal block grants and state funds, which we discuss in Appendix A.21
Table 3. Estimated TTW administrative costs for 2016
Cost category Amount (2016 $) Total 18,835,670 SVRA ticket assignments Subtotal 6,504,129 Staff 1,980,802 TPM contract 4,018,330 Printing and mailing 504,996 EN ticket assignments Subtotal 12,331,541 Staff 3,674,133 TPM contract 8,538,952 Printing and mailing 118,456 SOURCE: Authors' calculations based on O'Leary and Roessel (2018). ### Benefits of TTW Prior analyses of the utility of employment services generally measured success based on the earnings of the client after the completion of services (for example, Ashenfelter 1978; Couch 1992; Dean, Dolan, and Schmidt 1999; and Dean and others 2001, 2015). Although a client's postservice earnings are of interest to SSA, they are not an ideal measure of TTW's effectiveness and efficiency. To SSA, the more important question is whether these services lead to a decreased reliance on cash benefits (Dean and others 2014), and more specifically, whether the reduction in benefits linked to TTW services is greater than what SSA pays for those services. SSA recently developed BFW, a new measure that uses an algorithm to calculate the cash benefits given up over time when beneficiaries start working (Mathematica 2022). BFW has been incorporated into the DAF, enabling us to use it for this analysis. Linking TTW service data with the BFW data in the DAF allows us to compare the cost of these services with any subsequent decrease in cash benefits because of work. We examine the effect of TTW services by following a client cohort over time. A successful progression through employment services generally begins with enrollment (ticket assignment), followed by service provision, then employment, possibly involving several attempts. Because the traditional cost reimbursement system and the newer TTW payment systems are all outcome-oriented, some level of employment success is necessary before SSA begins to incur costs in the form of employment service provider payments. For reimbursement under the traditional payment system, an SVRA's client must attain earnings of SGA level or higher for at least 9 months in a 12-month period. The TTW payment systems are more complex.22 Recall that SVRAs that opt for payment under one of these systems are effectively ENs. ENs can qualify for a phase 1 milestone payment, a phase 2 milestone payment, and an outcome payment.23 An EN qualifies for a phase 1 milestone payment when the beneficiary reaches 1, 3, 6, and 9 months of earnings at the TWP level ($810 in 2016). An EN qualifies for a phase 2 milestone payment each month that the beneficiary earns at or above SGA level. Outcome payments require that the beneficiary be in STW status.
For an SSI recipient, earnings of more than $85 per month can trigger a benefit reduction. As such, a reduction can take effect rather quickly, although the dollar reduction is usually modest. For DI beneficiaries, by contrast, there are no partial reductions in benefit amounts, and they must complete a TWP before attaining STW status, although the benefit reduction amounts are typically more substantial. Because of these differences, it is unclear whether TTW is more cost-effective for SSI recipients or DI beneficiaries. DI beneficiaries are better candidates for employment because of their work histories, but they typically are also older, are more likely to have physical disabilities that are associated with poorer return-to-work outcomes, and must sustain employment longer to generate benefit reductions. Conversely, SSI recipients tend not to have extensive work histories, but they are younger, are more likely to have mental conditions that are associated with better return-to-work outcomes, and can generate benefit reductions sooner (SSA 2020). Regardless of the payment system, positive employment outcomes take time to occur. Clients might take a year or two to complete employment services, with another year to find stable employment, and, for DI beneficiaries, still another year to complete their TWP. Only then does the beneficiary enter an extended period of eligibility during which benefits are suspended because of work. Thus, substantial benefit reductions are likely to take 3–4 years after enrollment to emerge, and even longer if the labor market sours or the participant does not quickly find stable employment. Further, because the cost of employment services can be high, and SSA pays at least a portion of those costs before the client accrues substantial work duration, a long time may pass before the value of benefits not paid because of work covers the cost of services. Because it takes time to see whether TTW outcomes may have offset costs, we examine a 2006 cohort of TTW participants and follow them through receipt of employment services and any attainment of STW status that ensues through 2016.24 We selected the 2006 cohort because pre-2006 cohorts participated in TTW while its rollout was not yet complete, and the experiences of the 2007–2009 cohorts were more directly affected by the anomalous economic conditions of the Great Recession. Employment outcomes for the 2008–2011 cohorts were lower than those for 2006, but beginning with the 2013 cohort, inflation-adjusted outcomes again approached the 2006 levels. The 2006 cohort should thus provide representative results for a period of relative economic stability.25 Under both the TTW and traditional payment systems, some payments occur before a beneficiary maintains work for a substantial period. This means SSA pays providers for some beneficiaries whose work effort never reduces benefit payments enough to fully offset the service costs. However, service providers must submit payment requests with documentation, as appropriate, in a timely manner to be eligible to receive those payments. Because service providers do not always complete these payment-request steps within program-required limits, some beneficiaries receive services and attain employment that reduces SSA's benefit costs without generating SSA payments to ENs or SVRAs.26 We track TTW participants by the type of provider to which they assigned their ticket and by whether SSA made payments to the provider. Table 4 shows the extent to which 2006 DI beneficiaries or SSI recipients aged 18–65 in January 2006 participated in TTW services during 2006 and had their cash benefits suspended because of work that followed employment-service receipt.27 Table 4. TTW participation in 2006 and employment outcomes as of 2016 TTW participation and outcome Number Percent Attained STW status by December 31, 2016 (%) a Total 11,122,282 100.00 -- Never enrolled in TTW (through 2016) 10,982,613 98.74 3.2 Enrolled in SVRA services 135,363 1.22 18.7 SVRA received provider payment by year-end 2016? No 127,945 1.15 15.4 Yes b 7,418 0.07 76.3 Enrolled in EN services 4,306 0.04 28.6 EN received provider payment by year-end 2016? No 3,191 0.03 16.7 Yes b 1,115 0.01 62.7 SOURCE: Authors' calculations using 2016 DAF. NOTES: Includes DI and DI/SSI beneficiaries and SSI recipients who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who enrolled in an SVRA or an EN before or after 2006. -- = not available. a. Applies to individuals who received neither DI benefits nor SSI payments in at least 1 month because of work. b. Includes some individuals who generated payments to both an SVRA and an EN under a single ticket assignment. These cases most likely reflect a TTW initiative called Partnership Plus that enables a client to transfer an ongoing assignment from one provider type to the other. SSA's DAF indicates STW status as well as the BFW measure mentioned above. SSA created STW status as a research variable because the agency's administrative data do not specifically identify work as a reason for a suspension or termination. SSA uses an algorithm to compare an individual's benefit status with information on work, earnings, other income, medical reviews, retirement, and death to determine whether benefit suspension or termination resulted from work or for one of these other reasons (Mathematica 2022). Table 4 shows that very few beneficiaries enrolled in TTW in 2006. Of the 11.1 million beneficiaries on the rolls at some point in 2006, only 1.2 percent enrolled for SVRA services that year and only 0.04 percent enrolled for EN services. Yet those who enrolled for services had substantially better employment outcomes through the end of 2016 than those who did not. Of those who could have enrolled in TTW in 2006 but did not, only 3.2 percent reached STW status for at least 1 month by the end of 2016. For those who enrolled in SVRA services in 2006, the proportion was 18.7 percent and for those entering EN services in 2006, it was 28.6 percent. As might be expected, those who generated SSA payments to their service provider had even higher rates of STW status by the end of 2016. Of those generating SVRA payments as of year-end 2016, 76.3 percent attained STW status for at least 1 month, while of those generating EN payments, 62.7 percent reached STW status for at least 1 month. Table 5 shows the values of BFW and the costs incurred for those beneficiaries under TTW. Table 4 showed that 3.2 percent of the 2006 cohort was able to reach STW status without the help of EN or SVRA services and Table 5 shows that this small share of beneficiaries nonetheless generated significant BFW. This is because 3.2 percent of such a large base (nearly 11 million) is a substantial number of (current and former) beneficiaries. Through 2016, those who were eligible for TTW services in 2006 but did not use them generated nearly$16 billion in gross BFW—benefits that were not paid because those beneficiaries were in STW status. Because those beneficiaries received no services, there are no service costs and the net BFW are this same $16 billion. Table 5. TTW participation in 2006 and BFW and cost outcomes as of 2016 TTW participation and outcome Number BFW and costs through December 31, 2016 (millions of 2016$)
Gross BFW Administrative costs a Payments to service providers Net BFW
Total 11,122,282 16,647.2 18.8 119.2 16,509.2
Never enrolled in TTW (through 2016) 10,982,613 15,881.3 0.0 0.0 15,881.3
Enrolled in SVRA services 135,363 711.7 6.5 108.9 596.3
SVRA received provider payment by year-end 2016?
No 127,945 454.5 6.1 0.0 448.4
Yes b 7,418 257.2 0.4 108.9 147.9
Enrolled in EN services 4,306 54.2 12.3 10.3 31.6
EN received provider payment by year-end 2016?
No 3,191 8.8 9.1 0.0 -0.3
Yes b 1,115 45.3 3.2 10.3 31.8
SOURCE: Authors' calculations using 2016 DAF and O'Leary and Roessel (2018).
NOTES: Includes DI and DI/SSI beneficiaries and SSI recipients who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who enrolled in an SVRA or an EN before or after 2006.
Totals do not necessarily equal the sum of rounded components.
BFW and costs for TTW participants exclude those resulting from any subsequent ticket assignments.
a. 2017 costs adjusted to 2016 dollars.
b. Includes some individuals who generated payments to both an SVRA and an EN under a single ticket assignment. These cases most likely reflect a TTW initiative called Partnership Plus that enables a client to transfer an ongoing assignment from one provider type to the other.
The smaller proportions of beneficiaries that used EN and SVRA services are reflected in the lower BFW results. Overall, each dollar spent by SSA on SVRA services resulted in more than $6 in gross BFW, while each dollar spent on EN services generated more than$2 in gross BFW. SVRA clients who enrolled in 2006 ultimately generated $711.7 million in gross BFW,$6.5 million in administrative costs, and $108.9 million in provider reimbursement costs, leaving$596.3 million in net BFW. Those who enrolled with ENs generated $54.2 million in gross BFW,$12.3 million in administrative costs, and $10.3 million in provider payments, leaving$31.6 million in net BFW.
Interestingly, Table 5 also shows substantial gross BFW in cases that never generated a payment to a service provider: $454.5 million for SVRA users and$8.8 million for EN users. This can occur for a variety of reasons, but the most likely cause is service providers losing track of some participants who find work. Unaware of their clients' employment success, the providers are not timely in their request for payment from SSA (Stapleton and others 2010). With minimal administrative costs and no provider reimbursements in these instances, the net BFW are nearly equal to the gross BFW for these SVRA users. For EN users, the administrative costs more than offset the gross BFW, leaving a net loss of $0.3 million in these cases. For clients who generate provider payments, combined administrative costs and provider payments reduce gross BFW by 42 percent for SVRA enrollees and by 30 percent for EN enrollees, leaving net BFW of$147.9 million and $31.8 million, respectively. Although the total amounts show the scale of BFW, they are not useful for examining TTW's relative efficiency. Table 6 repeats Table 5 with per-beneficiary averages in place of total amounts. Beneficiaries in 2006 who never enrolled in TTW services generated a relatively modest average net BFW of$1,446. SVRA clients who generated no payments to their providers averaged $3,504 in net BFW. SSA's cost for EN clients who generated no provider payments exceeded gross BFW by$99 per beneficiary.
Table 6. TTW participation in 2006 and BFW and cost outcomes per beneficiary as of 2016
TTW participation and outcome Number BFW and costs through December 31, 2016 (2016 $) Gross BFW Administrative costs a Payments to service providers Net BFW Total 11,122,282 1,497 2 11 1,484 Never enrolled in TTW (through 2016) 10,982,613 1,446 0 0 1,446 Enrolled in SVRA services 135,363 5,258 48 805 4,405 SVRA received provider payment by year-end 2016? No 127,945 3,552 48 0 3,504 Yes b 7,418 34,672 48 14,682 19,942 Enrolled in EN services 4,306 12,579 2,863 2,392 7,324 EN received provider payment by year-end 2016? No 3,191 2,764 2,863 0 -99 Yes b 1,115 40,671 2,863 9,237 28,571 SOURCE: Authors' calculations using 2016 DAF and O'Leary and Roessel (2018). NOTES: Includes DI and DI/SSI beneficiaries and SSI recipients who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who enrolled in an SVRA or an EN before or after 2006. BFW and costs for TTW participants exclude those resulting from any subsequent ticket assignments. a. 2017 costs adjusted to 2016 dollars. b. Includes some individuals who generated payments to both an SVRA and an EN under a single ticket assignment. These cases most likely reflect a TTW initiative called Partnership Plus that enables a client to transfer an ongoing assignment from one provider type to the other. The average net BFW for SVRA clients who generated a provider payment were nearly$20,000 and the average net BFW for EN enrollees who generated a provider payment were about 50 percent higher, at nearly $30,000, despite ENs' higher administrative costs. This is because average gross BFW are significantly higher for EN enrollees than for SVRA enrollees, while average EN provider payment amounts are significantly lower. For TTW enrollees overall, disregarding provider payment status, EN clients generated substantially higher average net BFW ($7,324) than SVRA clients ($4,405). Although it is tempting to conclude from Table 6 that EN services are more expensive than SVRA services but attain significantly better outcomes, that is a misleading oversimplification. EN services are more costly to SSA but differences in the SVRA and EN cost structures and client populations, detailed in Appendix A, result in a significant portion of SVRA costs being borne by state and federal governments through block grants.28 Further, costs are not distributed evenly across TTW participants; those with greater employment success incur higher administrative and service costs than those with less success. Further still, because SVRAs and ENs are subject to different enrollment rules, SVRAs receive far more ticket assignments than ENs and are reimbursed for a much smaller fraction of their clients (5 percent, versus 26 percent for ENs). Because costs are linked to success, average costs for SVRAs are significantly lower than those for ENs. Although this poses no problem for comparing administrative and provider-payment costs with BFW, as in Table 6, simple averages cannot tell us what the expected costs for a typical EN participant would be under an SVRA assignment or vice versa. Would the typical EN (or SVRA) participant be more (or less) successful than the typical SVRA (or EN) participant and thereby generate costs to SSA that are higher (or lower) than those of the other provider type, assuming similar results? In Appendix A we adjust for the differences in SVRA and EN clientele and show that the average costs by provider type are similar—even if we ignore the effects of block grants. These adjustments are imperfect, but they imply that shifting clients from SVRAs to ENs and vice versa is unlikely to significantly change the overall cost of providing employment services to SSA disability program beneficiaries. Beyond this, the higher BFW values attained by EN clients also reflect differences stemming from the enrollment rules under which the ENs and SVRAs operate. ENs are allowed to choose which beneficiaries they will serve while SVRAs are required to serve anyone they are able to help and, if they are over capacity, must serve those with the most severe disabilities first. Thus, SVRAs could be expected to have a harder-to-serve clientele, on average, than ENs have. In the same way that one would not expect the average cost for one provider type to apply to the other, one would not expect the average success rate for one provider type to apply to the clientele of the other: an SVRA's (or EN's) success would improve (or decline) if it served the other provider type's clientele. Rather than comparing costs and outcomes between ENs and SVRAs, the point to be drawn from Table 6 is that participants in both ENs and SVRAs attain BFW that are significantly greater than their costs to SSA, and the results are far better than those for beneficiaries who get no SSA-funded services. Although the outcome comparisons in Table 6 are interesting, the comparisons between service recipients and nonrecipients are likely to include significant bias because seeking services is itself a strong signal of interest in work. That bias would tend to make TTW outcomes look better than they really are because TTW participants represent a more motivated subpopulation among beneficiaries. We can adjust for this bias by limiting the analysis to DI beneficiaries who have completed a TWP. That group is not representative of all beneficiaries; it consists only of those who received DI benefits (either with or without concurrent SSI payments) and worked enough to earn at the trial work level (in 2016, at least$810 per month) for 9 or more months within a span of 12 consecutive months. The TWP duration and earnings criteria remove much of the bias in Table 6 in that they require the willingness and the ability to work at a substantial level, regardless of whether the beneficiary seeks employment services. However, a serious interest in work is not the only potential bias related to service use. Those who receive services presumably believe they need them. To the extent they are correct, one might expect these beneficiaries, in the absence of services, to have poorer employment outcomes than beneficiaries who forgo services, all else being equal. So, although we adjust for motivation toward work by restricting the analysis to beneficiaries who complete a TWP, the negative bias of service users needing those services likely remains.
Using TWP completion to control for work effort and aptitude narrows our examination to a subset of beneficiaries; therefore, any results for that group cannot be extrapolated for the larger group. Nevertheless, restricting to those with TWP completion allows us to intuitively account for bias and reveal more accurate net effects of TTW for at least this subset of beneficiaries. Table 7 shows the average BFW and costs for beneficiaries who were eligible for TTW services in 2006 and subsequently completed a TWP. Of the beneficiaries who never enrolled in TTW, only 3.0 percent (333,659) ever completed a TWP; and while only 3.2 percent of TTW nonenrollees overall ever attained STW status, 48.8 percent of those who completed a TWP did. Average net BFW also differed dramatically, at $1,446 for TTW nonparticipants overall (Table 6) and$27,387 for those who eventually completed a TWP (Table 7). Controlling for TWP completion also changes the STW-status and BFW numbers for TTW participants, although by significantly smaller proportions. Comparing Tables 4 and 7 shows that STW status increases from 18.7 percent for SVRA participants overall to 50.2 percent for those who completed a TWP, and from 28.6 percent to 60.4 percent for EN participants. Among those who completed a TWP, average gross BFW for SVRA clients are $17,622 and for EN clients they are$31,812. Although the average gross BFW for all SVRA clients in Table 7 are lower than those for TTW nonparticipants, the average gross BFW for TTW participants whose service providers received SSA payments are much higher than those for nonparticipants ($43,742 for SVRA clients and$53,410 for EN clients). Accounting for TTW costs drops the average net BFW further below the level for nonparticipants (who had no service costs) for both SVRAs and ENs overall, but for cases that generated SSA payments for services, the average net BFW still exceed those for nonparticipants.
Table 7. TTW participation in 2006 and employment outcomes for beneficiaries who completed a TWP as of 2016
TTW participation and outcome Number Attained STW status by December 31, 2016 (%) a Per-beneficiary BFW and costs through December 31, 2016 (2016 $) Gross BFW Administrative costs b Payments to service providers Net BFW Never enrolled in TTW (through 2016) 333,659 48.8 27,387 0 0 27,387 Enrolled in SVRA services 23,431 50.2 17,622 48 2,457 15,117 SVRA received provider payment by year-end 2016? No 19,400 43.5 12,195 48 0 12,147 Yes c 4,031 82.7 43,742 48 14,285 29,409 Enrolled in EN services 1,303 60.4 31,812 2,863 5,837 23,112 EN received provider payment by year-end 2016? No 621 45.6 8,094 2,863 0 5,231 Yes c 682 73.9 53,410 2,863 11,152 39,395 SOURCE: Authors' calculations using 2016 DAF and O'Leary and Roessel (2018). NOTES: Includes DI and DI/SSI beneficiaries who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who had entered STW status before 2006, or who enrolled in an SVRA or an EN before or after 2006. BFW and costs for TTW participants exclude those resulting from any subsequent ticket assignments. a. Applies to individuals who received neither DI benefits nor SSI payments in at least 1 month because of work. b. 2017 costs adjusted to 2016 dollars. c. Includes some individuals who generated payments to both an SVRA and an EN under a single ticket assignment. These cases most likely reflect a TTW initiative called Partnership Plus that enables a client to transfer an ongoing assignment from one provider type to the other. Table 7 may also indicate the effect of differing levels of need for services in the difference between outcomes for ENs, which can choose whom they serve, and SVRAs, which cannot. Thus, the poorer outcomes for SVRAs could reflect a clientele that not only needs services to succeed, but also needs more intensive services than those provided by ENs. These findings suggest that, even when we restrict our analysis to beneficiaries who completed their TWP, significant differences remain between those who do and do not receive services, and between those who receive services from ENs versus SVRAs. Table 8 compares the characteristics of DI beneficiaries who completed a TWP for each of the three types of employment service use (none, SVRAEN). EN clients were the quickest to start working and had higher average initial earnings than SVRA clients. Although it took SVRA clients longer than EN clients to start work after assigning their tickets, the median time differed by only 6 months. Table 8. Characteristics of DI beneficiaries on the rolls in 2006 who completed a TWP by December 2016, by type of employment service received in 2006 Characteristic None SVRA EN Number of beneficiaries 333,659 23,431 1,303 Average age 43.9 37.9 42.6 Average monthly benefit (2016$) 985 908 979
Benefit type (%)
DI only 85.7 82.6 91.1
DI and SSI concurrently 14.3 17.4 8.9
Sex (%)
Men 48.2 53.9 47.0
Women 51.8 46.1 53.0
Impairment type (%)
Musculoskeletal system disorder 25.2 11.8 19.3
Psychiatric disorder 33.2 39.8 44.3
Intellectual disability 6.1 11.8 5.4
Sensory system disorder 2.0 13.7 4.1
Organ systems disorder 15.1 8.0 10.7
Nervous system disorder 5.3 5.8 5.7
Injuries 4.1 4.6 2.8
Blood disorders or infectious diseases 3.4 1.8 2.9
Neoplasms 3.9 1.0 3.1
Congenital anomalies 0.2 0.5 0.2
Skin disorders 0.3 0.1 0.2
Unknown 0.1 0.1 (X)
Other 1.3 0.8 1.5
Most recent work before starting benefits (%)
Did not work 4.4 5.9 2.7
2 or fewer years 25.4 20.0 23.9
3–4 years 2.8 1.9 1.8
5 or more years 1.0 0.7 1.2
Average number of months from disability onset to December 2006 93.4 98.2 102.0
As of December 2016, percentage who died a 8.8 4.8 8.9
Of those with any earnings as of December 2016—
Total earnings (thousands of 2016 $) 108,738 103,347 134,896 Median number of months to first earnings From January 2006 21 13 9 From ticket assignment . . . 9 3 Median first-month earnings (2016$) 582 493 573
Average number of months in STW status 18.9 18.6 26.7
SOURCE: Authors' calculations using 2016 DAF.
NOTES: Includes DI and DI/SSI beneficiaries who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who had entered STW status before 2006, or who enrolled in an SVRA or an EN before or after 2006.
Rounded components of percentage distributions do not necessarily sum to 100.0.
(X) = suppressed to avoid disclosing information about particular individuals; . . . = not applicable.
a. Includes only deaths occurring while receiving disability benefits or in STW status. Omits deaths occurring after conversion to retirement benefits or while benefits are suspended or terminated for reasons other than work.
Relative to the other service-type groups, service nonusers were significantly more likely to have musculoskeletal- or organ-system impairments, SVRA clients were significantly more likely to have intellectual or sensory-system disabilities or to receive concurrent DI and SSI benefits, and EN clients were less likely to have disabilities from injuries or to have no work experience prior to starting benefits. SVRA clients were also about half as likely to die during the observation period as were those in the other service-type groups, which likely reflects the younger average age of SVRA users. Consistent with Table 7, which shows that EN clients tend to attain higher BFW and are more likely to reach STW status than nonparticipants and SVRA users, Table 8 shows that EN clients also maintain STW status for a longer period.
### Multivariate Analyses
Differences in beneficiary characteristics are likely to account for the differences in TTW outcomes that remain after controlling for TWP completion. We can account for these differences by using the following simple ordinary least square (OLS) multivariate regression:
(1)
$Y=α+βX+δT+γε$
where:
$Y$ is our outcome,
$X$ is our vector of observable characteristics,
$T$ is a dummy indicating whether the beneficiary received TTW services, and
$ε$ is our error term.
Table 9 shows the regression results for total earnings, STW status attainment and duration, and gross BFW for DI beneficiaries who completed a TWP, controlling for the observable differences.
Table 9. OLS regressions relating DI beneficiary characteristics and employment service use to selected positive employment outcomes: Beneficiaries on the rolls in 2006 who completed a TWP by December 2016
Characteristic Aggregate earnings (thousands of 2016 $) Attained STW status (%) Months in STW status Per-beneficiary gross BFW (2016$)
Estimate Standard error Estimate Standard error Estimate Standard error Estimate Standard error
Intercept 109,256*** 1,518 0.854*** 0.005 40.91*** 0.29 40,971*** 450
Per year of age -1,882*** 29 -0.009*** 0.000 -0.62*** 0.01 -973*** 8
Per dollar of average monthly benefit 93*** 1 0.000*** 0.000 0.01*** 0.00 31*** 0
Benefit type (%)
DI only (reference category) . . . . . . . . . . . . . . . . . . . . . . . .
DI and SSI concurrently -42,116*** 812 -0.094*** 0.002 -8.76*** 0.15 -13,631*** 241
Sex (%)
Men 4,381*** 575 0.030*** 0.002 0.96*** 0.11 1,206*** 170
Women (reference category) . . . . . . . . . . . . . . . . . . . . . . . .
Impairment type (%)
Musculoskeletal system disorder (reference category) . . . . . . . . . . . . . . . . . . . . . . . .
Psychiatric disorder -11,561*** 773 -0.022*** 0.002 -1.83*** 0.15 -2,694*** 229
Intellectual disability -24,138*** 1,326 -0.138*** 0.004 -10.11*** 0.25 -10,077*** 393
Sensory system disorder 3,625** 1,788 -0.089*** 0.005 -3.41*** 0.34 -5,308*** 530
Organ systems disorder -2,418*** 914 -0.001 0.003 0.54*** 0.17 543** 271
Nervous system disorder -2,832** 1,330 -0.040*** 0.004 -1.06*** 0.25 -2,020*** 394
Injuries 30,569*** 1,483 0.037*** 0.004 6.07*** 0.28 9,450*** 440
Blood disorders or infectious diseases 11,992*** 1,635 0.049*** 0.005 4.00*** 0.31 3,797*** 485
Neoplasms 82,693*** 1,556 0.148*** 0.005 16.23*** 0.29 27,444*** 461
Congenital anomalies -4,070 5,641 -0.070*** 0.017 -4.73*** 1.06 -8,197*** 1,671
Skin disorders 3,977 5,445 -0.017 0.016 1.02 1.03 309 1,613
Unknown -491 11,916 -0.010 0.035 -0.66 2.25 1,293 3,532
Other 13,642*** 2,547 -0.013* 0.008 1.57*** 0.48 3,363*** 755
Most recent work before starting benefits (%)
Did not work (reference category) . . . . . . . . . . . . . . . . . . . . . . . .
2 or fewer years -7,506*** 645 0.009*** 0.002 0.38*** 0.12 -507*** 191
3–4 years -11,419*** 1,687 -0.009* 0.005 -0.79** 0.32 -2,188*** 500
5 or more years -22,143*** 2,745 -0.044*** 0.008 -2.50*** 0.52 -3,407*** 814
Per month from disability onset to December 2006 -27*** 3 0.000*** 0.000 0.00 0.00 0 1
TTW participation
Did not participate (reference category) . . . . . . . . . . . . . . . . . . . . . . . .
Assigned ticket to SVRA -4,808*** 1,144 -0.008** 0.003 -1.62*** 0.22 -10,601*** 339
Assigned ticket to EN 24,214*** 4,578 0.107*** 0.014 7.07*** 0.86 3,381** 1,357
R2 0.08 0.04 0.06 0.01
SOURCE: Authors' calculations using 2016 DAF.
NOTES: Includes DI and DI/SSI beneficiaries who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who had entered STW status before 2006, or who enrolled in an SVRA or an EN before or after 2006.
. . . = not applicable; * = statistically significant at the 90 percent level; ** = statistically significant at the 95 percent level; *** = statistically significant at the 99 percent level.
Given the large dataset (358,393 beneficiaries), it is not surprising that many of the parameter estimates are statistically significant. We therefore focus on those that are both significant and of greater magnitude. Across all four models, intellectual disability is significantly negatively associated with positive employment outcomes, while neoplasms have a significant positive relationship. Disability because of injury has significant positive effects on earnings, months in STW status, and BFW, and a modest positive effect on attaining STW status. Concurrent-benefit status is negatively associated with employment outcomes in all models but the magnitude of the effect on attaining STW status is small.
Longer periods between last employment and first benefit are negatively associated with earnings and BFW, although only the earnings magnitudes are large. Disabled-worker beneficiaries must by definition have work histories, so DI beneficiaries without prior earnings must qualify either as disabled widow(er)s or disabled adult children with eligibility based on the work history of a spouse or parent who is disabled or has retired or died. These results suggest that, among beneficiaries who completed a TWP, surviving spouses and adult children tend to have the highest earnings; but among those with work histories, recency of work is associated with higher earnings. For the two STW-status regressions, the signs in the results are more in line with expectations in that those who worked within 2 years of benefit commencement had positive STW-status outcomes, but the magnitudes are small. Further, among TWP completers, both age and sex have limited effects on outcomes, although results are consistent with other research, as employment success declines with age and men are more likely than women to attain employment.
After accounting for these characteristics, our results are roughly consistent with those of the simple outcome analysis in Table 7. Table 9 also shows that those who received EN services attained $24,214 more in total earnings than those who received no services. Further, they were 10.7 percent more likely to reach STW status, accrued 7.07 more months in STW status, and accounted for$3,381 more in gross BFW through the end of 2016 (versus the $4,425 difference indicated in Table 7). Relative to those who did not receive employment services, SVRA clients had lower total earnings, attained and retained STW status at about the same levels, and accounted for$10,601 less in gross BFW (compared with the $9,765 difference indicated in Table 7). We can also use TWP completion status to model gross BFW on the full DI population using a Heckman two-stage selection model. The Heckman model was developed to produce regression estimates—for example, of wages—for an entire population when input data are available for only a subset of the population—for example, those who work (Heckman 1974, 1976). Without such a model, any estimate based on only the wages of workers would be biased and tend to overstate wages for nonworkers. Whether individuals work is related to wage rates: They will work only if they can earn above a particular amount. The Heckman model uses information on the work decision (which, unlike that for wages, is available for everyone) to adjust the wage equation for those who do work. It solves the bias problem by estimating a first-stage equation on the probability of work (that is, the probability of having wages) based on characteristics that drive the work decision. From this equation, one can calculate the inverse Mills ratio, $λ$, which provides a measure of the selection bias driving whether an individual works, and thus has earnings, for the wage equation. By including $λ$ in the second-stage wage equation, the Heckman model can produce unbiased wage estimates for the entire population. Although Heckman developed this technique in the context of wages and work, it can apply to other situations where outcome data are only available for a subpopulation that is defined by a participation decision. For our purposes, we can use it to estimate dollar outcomes (BFW) that are subject to exceeding a threshold value. We use the following model to estimate BFW: (2) $Y=α+βX+δT+γA+ρN+ε$ where: $Y$ is the BFW outcome, $X$ is the vector of observable characteristics, $T$ is a dummy indicating whether the beneficiary receives TTW services, $A$ is aptitude for self-supporting work, and $N$ is need for assistance in attaining self-supporting work. $A$ and $N$ are unobservable, yet they determine whether we have data on $Y$. If we run our analysis on the full population and do not account for these unobservable variables, we will have biased results. In the regressions in Table 9, we adjusted for $A$ by including only those who had completed a TWP. Under the Heckman model, we include all DI beneficiaries and modify equation 2 as follows: (3) $Y=α+βX+δT+ρN+μ$ (4) We drop the unobservable quantity $A$ from equation 3 and add equation 4, the selection equation, with $B$ as the threshold dummy variable indicating whether we see outcome $Y$. For our analysis, only a person with sufficient aptitude and desire for self-supporting work generates BFW; that is, when $γX′+υ≥0$. We substitute $T$, the completion of the TWP, for $B$ as our selection variable. Both $B$ and $T$ are indicators of self-supporting aptitude; but whereas $B$ indicates that self-supporting work has occurred, $T$ indicates the broader condition that self-supporting work is possible and the beneficiary is sufficiently motivated to attain it.29 Another advantage of using TWP completion is that it is an SSA program variable (meaning that administrative data track the count precisely) while BFW is a constructed variable, constituting an estimate generated from an algorithm (Mathematica 2022). Also, note that our selection equation only addresses selection that is due to aptitude for self-supporting work. The variable $N$, the need for assistance to get to self-supporting work, remains unobservable because our Heckman model does not have a proxy for it, so it is omitted and our results will retain some bias. Note also that $A$ and $N$ work in opposite directions: omitting $A$ will tend to overstate the effect of TTW services, $δ$, and omitting $N$ will tend to understate $δ$. Equation 4 is our first-stage selection equation on the probability of completing the TWP, and equation 3 is our second-stage estimate of BFW, adjusted for those who do complete their TWP and thus are unlikely to have nonzero BFW. Notice that we use the vector of independent variables,$X′$, in the selection equation rather than $X$. To implement the Heckman approach properly, we need exclusion restrictions both to minimize correlation between $λ$ and the vector of independent variables and to facilitate model identification.30 To do so, we want to include independent variables in stage one that predict selection into the TWP-completion group but do not predict the BFW, at least not directly. Although equations 3 and 4 include many of the same independent variables, only the selection equation includes whether the beneficiary died before the end of the observation period. This variable is meant to proxy for health (as distinct from disability) in that it seems likely that many beneficiaries with short life horizons will be aware of that likelihood and will be less likely to pursue work at substantial levels as a result. We also exclude the two variables that, based on Table 9, are related more to earnings (stage 2) than to the decision to work at a substantial level (stage 1): most recent work before benefits and benefit type (DI only versus concurrent DI/SSI). The Heckman model results are shown in Table 10. Table 10. Heckman selection model regressions relating beneficiary characteristics and employment service use to selected positive employment outcomes: Beneficiaries on the rolls in 2006 with outcomes as of December 2016 Characteristic Stage 1: Probit regression on TWP completion Stage 2: OLS regression on gross BFW (including inverse Mills ratio from stage 1) Estimate Standard error Estimate Standard error Intercept 0.046*** 0.004 65,938*** 650 Per year of age -0.030*** 0.000 147*** 22 Per dollar of average monthly benefit . . . . . . 31*** 0 Benefit type DI only (reference category) . . . . . . . . . . . . DI and SSI concurrently . . . . . . -13,509*** 241 Sex Men -0.048*** 0.002 3,550*** 185 Women (reference category) . . . . . . . . . . . . Impairment type Musculoskeletal system disorder (reference category) . . . . . . . . . . . . Psychiatric disorder -0.017*** 0.002 -1,773*** 243 Intellectual disability -0.331*** 0.004 2,027*** 469 Sensory system disorder 0.079*** 0.005 -7,824*** 565 Organ systems disorder 0.011*** 0.003 2,366*** 287 Nervous system disorder -0.166*** 0.004 4,338*** 430 Injuries 0.007* 0.004 9,409*** 465 Blood disorders or infectious diseases 0.276*** 0.005 -4,693*** 543 Neoplasms 0.227*** 0.005 23,588*** 494 Congenital anomalies -0.413*** 0.017 7,434*** 1,785 Skin disorders 0.018 0.017 147 1,715 Unknown -0.157*** 0.033 6,776* 3,704 Other -0.151*** 0.007 9,370*** 795 Most recent work before starting benefits Did not work (reference category) . . . . . . . . . . . . 2 or fewer years . . . . . . -704*** 190 3–4 years . . . . . . -2,509*** 496 5 or more years . . . . . . -3,672*** 807 Per month from disability onset to December 2006 -0.002*** 0.000 56*** 1 Died by December 2016 -0.476*** 0.003 . . . . . . TTW participation Did not participate (reference category) . . . . . . . . . . . . Assigned ticket to SVRA . . . . . . -10,692*** 339 Assigned ticket to EN . . . . . . 3,544** 1,351 λ . . . . . . -42,374*** 754 R2 . . . 0.11 SOURCE: Authors' calculations using 2016 DAF. NOTES: Includes DI and DI/SSI beneficiaries and SSI recipients who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who had entered STW status before 2006, or who enrolled in an SVRA or an EN before or after 2006. . . . = not applicable; * = statistically significant at the 90 percent level; ** = statistically significant at the 95 percent level; *** = statistically significant at the 99 percent level. In the first-stage (probit) regression, congenital anomalies and intellectual disability have strong negative correlations, relative to musculoskeletal system impairments, with completing a TWP. The same is true, to a lesser degree, for nervous system impairments. Not surprisingly, death before the end of the observation period is also strongly and negatively associated with TWP completion. Alternatively, blood disorders/infectious diseases and neoplasms are positively, and strongly, associated with TWP completion. Being male, older, and with longer time on the rolls are all negatively associated with TWP completion, but the effects are relatively small. In the second-stage (OLS) regression, recipients of concurrent DI/SSI payments have significantly lower gross BFW than DI-only beneficiaries, by$13,509 on average. Relative to musculoskeletal impairments, sensory system disorders and blood disorders/infectious diseases all significantly reduce gross BFW. Injuries and congenital anomalies are both associated with higher BFW relative to musculoskeletal impairments, but neoplasms are associated with the highest relative increase in BFW at $23,588. Higher monthly benefit amounts are also associated with higher BFW: An increase of just$100 in the monthly benefit is associated with a $3,100 increase in BFW. Given that DI benefits generally vary between$1,000 and $2,000 per month, this effect can be substantial. Not surprisingly, men are more likely to attain higher BFW levels than women, but the relative difference is modest ($3,550). Similarly, not having worked since 5 or more years before starting benefits has the expected negative effect, but again it is modest relative to those with no prior work ($3,672). The Heckman model results of greatest interest are the effects of SVRA and EN services. EN service use increased gross BFW over the period by$3,544 per beneficiary (relative to TTW nonparticipants) while the effect of SVRA service use under TTW was to reduce BFW over the period by $10,692. Both estimates are very close to the Table 9 OLS regressions on BFW ($3,381 and −$10,601, respectively). The parameter estimate for the inverse Mills ratio ($λ$) in the Heckman model is significant and, as expected, negative. The magnitudes of TTW effects estimated with the Heckman model are much smaller than those that would have resulted from running the regression without any selection adjustment for serious interest in work.31 We also find that the simple estimations of effects (Table 7) are close to the net effects resulting from the Heckman regression controlling for seriousness toward work and observable characteristics. In Table 10, those who received EN services attained$3,544 more on average in gross BFW through the end of 2016 than nonparticipants (compared with $4,425 more in Table 7), and those who received SVRA services attained$10,692 less in gross BFW per beneficiary than those with no services (compared with $9,765 less in Table 7). The simple analysis overstates the effect of TTW, but not by much. The costs shown in Table 7 are for beneficiaries completing a TWP. However, the Heckman estimate is for all recipients of DI or concurrent DI/SSI benefits regardless of TWP status. For that larger group, the TTW costs were$5,680 per EN client and $854 per SVRA client (not shown). Combining those figures with the gross BFW results in Table 10 suggests that neither EN nor SVRA services reduced SSA's costs through BFW in the years following a beneficiary's TTW participation. For EN clients, BFW through the end of 2016 recouped about two-thirds of costs and for SVRA clients, with negative net BFW, per participant costs sum to$11,546.32
However, as noted above, this is not the full story. Our Heckman model adjusts for serious interest in work, but it does not adjust for the fact that many who seek employment services do so because they think those services are necessary for them to succeed. If this self-assessed need is reasonably accurate, our regression—which ignores that assessment—will underestimate the effects of service use. The fact that SVRA service use has a negative, large, and significant effect for beneficiaries who are serious about work and complete their TWP clearly seems to indicate that SVRA clients may have greater barriers to employment success than other TWP completers do.
Also noteworthy is that the stage 2 regression model has a low R2 value, indicating that much of what drives these effects is not accounted for. This, in turn, means that even after limiting our analysis to those who have completed their TWP, significant quantities of information remain unobserved in the model. At least part of this missing information is likely due to the service needs of those who enroll in employment service programs.
Charts 2A and 2B track the earnings and employment outcomes of 2001 DI awardees to further examine potential bias related to beneficiaries' employment-service need. We shift the study cohort from 2006 beneficiaries to 2001 awardees to provide enough lead time for beneficiaries to have sorted themselves into the three types of employment service use: none, EN, and SVRA. We define the user groups by their status as of 2006, thus allowing beneficiaries 5 years from benefit start to decide whether to seek services, followed by a 10-year observation period that lets us track and compare their earnings and employment outcomes. To provide visual comparisons, Charts 2A and 2B also track earnings and employment outcomes for service nonusers who did not work until after 2006. However, our discussion focuses only on EN users, SVRA users, and service nonusers who worked as of 2006.
Show as table
Table equivalent for Chart 2A. Average earnings of 2001 DI awardees among those with earnings as of 2006 or later, by type of employment service use as of 2006, 2001–2016 (in thousands of 2016 dollars)
Year EN SVRA None (working by 2006) None (not working by 2006)
2001 7.725 5.583 8.916 . . .
2002 7.770 5.493 7.886 . . .
2003 6.732 6.460 9.021 . . .
2004 8.706 7.453 9.679 . . .
2005 10.459 8.322 9.981 . . .
2006 11.668 9.269 10.442 . . .
2007 13.352 10.469 11.611 4.398
2008 13.595 11.132 12.127 6.240
2009 14.552 11.868 12.764 7.750
2010 14.811 11.935 12.758 7.853
2011 14.883 12.133 12.955 8.238
2012 15.087 12.436 13.397 8.794
2013 14.460 12.789 14.009 9.192
2014 14.363 13.159 14.590 9.510
2015 14.639 14.011 15.450 10.257
2016 15.571 14.497 15.900 10.618
SOURCES: Authors' calculations using 2016 DAF; SSA (2020, 22).
Annualized SGA level = $13,560. Annualized TWP level =$9,720.
. . . = not applicable.
Show as table
Table equivalent for Chart 2B. Employment rate among 2001 DI awardees, by type of employment service use as of 2006, 2001–2016 (in percent)
Year EN SVRA None (working in 2006) None (not working in 2006)
2001 46.8 49.6 73.6 . . .
2002 32.3 39.6 36.1 . . .
2003 40.8 40.8 32.9 . . .
2004 49.0 42.7 32.8 . . .
2005 53.5 43.9 32.6 . . .
2006 56.8 44.0 32.8 . . .
2007 52.8 43.5 30.5 2.2
2008 48.4 41.4 28.6 2.9
2009 40.2 36.8 25.6 2.8
2010 38.1 35.1 24.6 3.2
2011 35.6 33.9 24.0 3.3
2012 33.7 33.4 23.8 3.5
2013 33.3 33.2 23.6 3.7
2014 33.4 33.5 23.6 4.1
2015 34.0 33.9 24.4 4.4
2016 32.8 34.6 25.0 4.9
SOURCES: Authors' calculations using 2016 DAF; SSA (2020, 21).
NOTE: Some beneficiaries who had not worked as of 2006 attained work in later years.
. . . = not applicable.
The charts cover 2001–2016; but because some 2001 awardees had prebenefit earnings in 2001, our first year of interest is 2002. As might be expected, beneficiaries who worked and did not seek services in the first 5 years on the benefit rolls had the highest average earnings in 2002, slightly above those of EN clients and substantially higher than those of SVRA clients (Chart 2A). For service nonusers who worked, earnings increased steadily over the observation period, and they had the highest average earnings, by a small margin, in the last few observation years. Although service users started the period with lower average earnings, EN clients reached and sustained higher earnings over time. SVRA clients started with average earnings well below the other groups and, over time, they reduced the earnings gap with service nonusers who worked, but did not equal them. By 2005, earnings for EN clients had surpassed those of service nonusers who worked, and by 2008, EN users' average earnings eclipsed the annualized SGA level. SVRA clients had closed about half the earnings gap with service nonusers who worked by 2006 and although they didn't further close the gap thereafter, their average earnings continued to climb, finally edging above SGA level by 2015.
All three of the service-use groups that Chart 2B tracks before 2007 had similarly low proportions of beneficiaries working in 2002. For service nonusers who worked, the rate was 36 percent in 2002 and declined thereafter. That downward trend likely reflects the workers who were unable to sustain employment, and as they dropped out, the culling effect likely played a significant part in the increase in earnings for service nonusers who work (Chart 2A), in that the beneficiaries who continued to work were pared down over time to only the highest earners in the group. Among EN users, only 32 percent worked in 2002 (Chart 2B), but the rate rose steadily and significantly through 2006. SVRA users had a higher employment rate in 2002 (41 percent) and the rate rose steadily, but less sharply than that of EN users, through 2006. More importantly, both the EN and SVRA users had earnings and employment-rate increases: Each year from 2003 to 2006, more enrollees worked, and they had higher earnings. Although the employment rates declined after 2006, they were, for both groups, about 10 percentage points higher in 2016 than the rate for service nonusers who had worked as of 2006.
Although the evidence is not definitive, Charts 2A and 2B support the hypothesis that beneficiaries who seek EN and (especially) SVRA services do so because they believe that they need those services, without which, such beneficiaries would be expected to have poorer employment outcomes than those who never seek services. The charts also suggest that EN services can fill clients' needs and SVRA services can at least ameliorate them.
## Limitations
This analysis focuses on the costs and effects of the TTW program and does not attempt to identify or account for any costs and effects related to other provisions of the authorizing legislation. Examples of the latter include costs associated with the elimination of work activity as a basis for reviewing an individual's disabled status, expedited reinstatement of benefits after a failed work attempt, outreach and support for the TTW Work Incentives Planning and Assistance initiative, and extended access to medical benefits, along with the previously mentioned protection of TTW participants from CDRs and the exclusion of unrecovered overpayments. Some of these costs are not specific to TTW and could be modified or eliminated irrespective of the program. As such, we treated them as general SSA costs that apply to all beneficiaries who work. Similarly, we did not account for computer system development costs that were related to or prioritized by TTW implementation, other than those included in the TPM contract. Although we do not attempt to account for these general SSA costs, we acknowledge that some of them may be used disproportionately for TTW participants.
We have reliable data on costs for services associated with beneficiaries who assigned their tickets in 2006 but we do not have 2006 data on administrative costs. We therefore substituted 2017 administrative costs adjusted to 2016 dollars. This substitution assumes that annual TTW administrative costs have been flat since 2006, which is not accurate; but we think it is reasonably close after we remove the nonsteady-state costs associated with TTW startup. To the extent that our estimates are lower than the true costs, program effects will be overstated.
Although our Heckman analysis adjusted for selection bias based on work aptitude and interest, it had no adjustment for service need. The negative need-for-service bias is likely to be substantial based on three findings in the analysis. First, we found that SVRA participation had a large, negative, and statistically significant effect on BFW. This defies common sense. Although it seems possible that helping someone build skills and find work has no discernible effect, it seems unlikely that a beneficiary who receives such services is worse off than one who receives no services at all. Perhaps some SVRA clients delayed a work start without getting anything useful from the SVRA during the delay. However, given that average gross BFW for SVRA clients are fully one-third less than those for service nonusers, and the median time from ticket assignment to work start is only 6 months longer for SVRA clients than for EN clients, it is hard to believe that the difference is due only to an employment delay caused by SVRA participation.
Second, we cannot determine how much of the difference between SVRA and EN outcomes is attributable to the success of the new service models under TTW and how much is due to bias from client self-sorting, based on need and ability, into ENs or SVRAs. We know from the contractor's evaluation that EN and SVRA services differ (Schimmel and others 2013) but we also know that ENs can choose which beneficiaries they serve while SVRAs cannot. Given that EN payments follow a fixed payment structure while SVRA payments use a reimbursement model, it seems likely that the beneficiaries with the greatest need end up at SVRAs. We cannot quantify differences in service need among TTW participants, but those unmeasured differences in client needs and abilities are likely to be the primary factors driving the differences between EN and SVRA outcomes. This seems evident in the earnings profiles of beneficiaries in the years after benefits begin, as those who seek SVRA services start out with significantly lower average earnings than either EN clients or service nonusers. Although SVRA clients' earnings improve significantly over time, and they narrow the gap with service nonusers, they remain the group with the lowest average earnings across the entire study period.
The selection of beneficiaries based on service need also suggests a limitation of the Heckman model for this analysis. The model assumes we can capture bias through the first-stage regression, but this works only if a single threshold variable can be used to capture the bias entirely. That seems unlikely in this instance, where the bias moves in two directions: increased aptitude for self-supporting work makes success more likely, while the need for assistance makes it less likely.
We have not attempted to build a comprehensive model of the factors affecting a beneficiary's likelihood of returning to work or leaving the disability benefit rolls. Instead, our analysis uses the available administrative data from the DAF on variables that are thought to be potential correlates with this behavior. Yet SSA data do not track several characteristics that could illuminate the analysis. These missing beneficiary characteristics include educational attainment, job characteristics prior to benefit start (such as industry, occupation, and job tenure), the stage at which benefits were awarded (initial determination, reconsideration, appeal), residual functional capacity, proximity to services, and access to transportation. Because SSA introduced an automated application processing system called the Electronic Disability (eDib) System, some of this information is available for beneficiaries applying from 2008 forward, but there are concerns about the completeness of the eDib data. In attempting to use eDib data for this analysis we encountered differences between eDib and DAF data, the causes of which we could not determine. Although we did not use eDib information in our analysis, its breadth remains an attractive extension for future study.
Another limitation is that our Heckman model excludes SSI recipients who do not receive concurrent DI benefits. This is because we use TWP completion as our threshold variable, and the TWP does not apply to SSI-only recipients. An alternative would be to use the STW-status variable, which applies to both SSI and DI and is conceptually similar to TWP completion. As noted earlier, however, we chose TWP completion because it is a program variable while the STW-status variable is constructed for the DAF. In one sense, STW status is a better choice in the Heckman setup: If one's benefits are suspended for work, BFW must be nonzero, in the same way that if work occurs, earnings are nonzero under the Heckman theoretical framework (Killingsworth 1983). However, STW status is a higher threshold than TWP completion for DI beneficiaries and a lower one for SSI. For DI, STW status implies TWP completion and at least 1 month of SGA after the end of the TWP. For SSI, STW status does not necessarily indicate a sustained work effort because it can occur for any month in which earnings are approximately double the SSI payment amount.33 Further analysis of the use of STW status as the threshold variable is worth examining in future research.
We made several assumptions in estimating TTW administrative costs. As noted in Appendix A, those costs are spread out over several years, so we approximate a single year's costs associated with the enrollee cohort. Although costs have changed over time, we use 2017 as a representative year for administrative costs because it is the best available estimate and represents a year in which TTW was operationally mature. It is likely that actual costs for 2006 were higher, but we think that many of those costs are attributable to TTW's startup status. We do not think the range of possible steady-state cost values for 2006 would materially affect our basic findings.34
## Summary
The TTW program was implemented with high hopes that it would significantly broaden access to employment services, efficiently fund those services, reduce dependency on cash benefits, and increase the proportion of beneficiaries who are able to exit the disability benefit rolls and live self-sufficiently, thereby generating savings to the Social Security trust funds (for DI) and the general fund of the treasury (for SSI).
Although some observers regard TTW as a failure, that conclusion is based narrowly on findings that TTW did not substantially increase disability program exits. Broader evidence shows that TTW accomplished other goals. It expanded the service options available to SSA disability program beneficiaries and increased enrollment in employment services overall. There is also evidence that TTW participation, for both EN and SVRA clients, has yielded positive earnings results, improving lives and reducing dependency on cash benefits. In addition, long-term net-outcomes analysis shows substantial BFW for TTW participants.
Finding that the TTW's effects were not as substantial as its designers had hoped does not mean that new EN services added under the program had failed. Because TTW superseded a preexisting SSA program to provide VR services, Mathematica's evaluation compared TTW's effects with those of that prior program—it did not assess the TTW effects relative to a no-services counterfactual. The evaluation found that TTW expanded service provision and participation without the decline in disability program exit rates that might have been expected as more beneficiaries (perhaps with poorer work prospects) enrolled for services. This means that services provided by ENs, combined with those offered by the preexisting SVRAs, were no less effective than those that were previously available to fewer potential clients, presumably with better median employment prospects, from SVRAs alone. Also of note: Although Mathematica did not find that TTW had a large effect on the disability roll exit rate, a smaller effect, not measurable with the methods available, may have occurred. Specifically, TTW increased STW status by less than 30 percent and the number of months in STW status by less than 9 percent—but the evaluation could not determine, with the available data, how closely the actual figures approached those ceilings.
Further, separate models assessing EN and SVRA services found better outcomes for ENs. TTW's introduction of ENs thus expanded service options and availability and reshuffled the service landscape while achieving the same benefit exit rate as the prior SVRA-only system. With increased service availability, beneficiaries were able to choose the providers that best met their needs.
The Mathematica evaluation examined TTW's marginal effect, but not the overall effect of the employment services. We therefore examined the net outcomes—program-associated costs and savings—for all beneficiaries. Analyzing program outcomes, without adjustments to account for selection biases, we found that TTW participants using either EN or SVRA services had much better employment results and, on average, accrued much higher BFW than nonparticipants. Then, adjusting for bias related to work interest and capability among employment service users, we limited the analysis to DI beneficiaries who had completed a TWP. Among this work-motivated group, we found that EN and SVRA clients accrued high average gross BFW, but average net BFW, after adjusting for average service costs, were lower for TTW service users than for TWP completers who received no services.
We next examined the effect of TTW services using more complex regression analyses to account for differences between service users and nonusers. Our Heckman model found that TTW employment service use, relative to nonuse of any services, increased gross BFW per beneficiary by $3,544 for EN users and reduced per-beneficiary gross BFW by$10,692 for SVRA users over the 2006–2016 study period. We also found that the simple adjusted outcomes, when restricted to DI beneficiaries who were TWP completers, were close to the more complex regression results. This is a useful finding: Because the simple model is intuitive and easy to explain, and provides similar results, it serves as a proxy for the more accurate and complex econometric models and can illustrate the results to a broader audience.
## Conclusions
Although this analysis clarifies TTW's effects, significant questions remain. We show that simple outcome measures can be misleading because they do not account for the biases inherent in who does and does not seek services. Restricting the analysis to DI beneficiaries who completed a TWP and applying the Heckman model both seem to work reasonably well in adjusting for serious interest in work. However, neither of these approaches account for bias related to the differences in service needs between service users and nonusers, so the actual effects are likely greater.
By adjusting for interest in work but not for self-assessed need of services, our estimates appear to represent a lower bound for TTW effects. Unfortunately, this finding does not address whether savings from benefit reductions cover TTW costs: accounting for the beneficiary's need for service would likely increase the estimated benefits of TTW, and would likely erase the apparent negative outcomes of SVRA services, but perhaps not enough to fully offset EN and SVRA service costs. The absence of clear findings after nearly 2 decades of observation, evaluation, and analysis underscores the difficulty in estimating definitive effects without a well-designed randomized control trial. The quasiexperimental methods used thus far simply do not seem capable of capturing the complex biases inherent in the return-to-work decisions facing beneficiaries with disabilities.
Still, our analysis finds that EN services, for which service need is less likely to be a limiting factor, significantly boost client earnings, STW status, and BFW for DI beneficiaries. This, along with Mathematica's finding that the combined employment outcomes for EN and SVRA services under TTW were similar to the pre-TTW SVRA-only outcomes, suggests that SVRAs are likely more successful than the Heckman analysis implies: DI beneficiaries who use EN services would have been as successful under the old system as they are under TTW. If this were not the case, then overall employment success would have improved when SSA switched from SVRA services only to the hybrid SVRA/EN model under TTW. It may be that pre-TTW SVRAs succeeded only with clients who have self-sorted into using ENs under TTW, but that seems unlikely. The likelier scenario is that SVRAs have a range of successes across the continuum of beneficiaries they serve and that SVRA clients with lower service needs have positive outcomes like those attained by EN clients. Other SVRA clients with greater service needs probably have poorer outcomes, but it seems unlikely that those outcomes are worse than they would have been with no services (as the Heckman model implies) when the SVRAs seem capable of achieving significant positive results for other clients. Further, the Heckman model's large negative finding for SVRA users suggests that the service-need bias that remains in the model could be quite substantial and that removing the bias could lead to significantly larger estimated effects for both ENs and SVRAs.
We also find that it seems unlikely for TTW or any alternative return-to-work program to significantly improve on the TTW's results. TTW offered many innovations to address perceived shortfalls of previous programs:
• It enables payment for outcomes rather than reimbursing only for costs. Reimbursements to SVRAs are predicated on the client reaching SGA in any 9 out of 12 consecutive months, while EN payments are tied more directly to employment outcomes and long-term success.35
• It removes several barriers to work that had been identified as keeping beneficiaries from leaving the rolls. TTW significantly extended health insurance coverage for former beneficiaries after leaving the rolls for work, eased a return to benefits if the beneficiary's work attempt failed, and offered protections from CDRs while enrollees participated in the program.
• It expanded service choice by offering services from ENs as an alternative to SVRAs. Although many ENs were VR vendors offering services as ENs much like those they offered under contract with SVRAs, some, such as consumer-directed service ENs and employer ENs, offered entirely new service models. TTW also likely expanded the availability of services, as ENs were able to absorb excess demand from SVRAs that reached capacity and went into order of selection status.
Combined, these TTW innovations affected employment service participation, but they have not led to large increases in disability program exits. It is hard to imagine how further changes in incentives, or the removal of additional barriers, could both remain within the current benefit rules and result in significantly more program exits than we have seen under TTW.
The 2008 change in TTW regulations is also instructive. As discussed in Livermore, Hoffman, and Bardos (2012), the new regulations increased TTW participation and seem to have drawn beneficiaries with greater work challenges on average than those who participated before 2008. Schimmel and others (2013) found that these newly induced participants were less successful in finding work than prior TTW participants had been, which led to an overall decline in STW status:
The recession almost certainly explains some and possibly most of the adjusted decline in the percentage [of participants] with at least one [STW-status] month [−39 percent], but other explanations are possible. In particular, the regulatory changes increased incentives to serve beneficiaries with a lower likelihood of sustaining high levels of earnings.
The authors found similar results for BFW.
Together, these findings suggest that TTW may have reached the maximum number of beneficiaries who are able and wish to work and can be served by employment service providers. This does not mean that employment programs for disability program beneficiaries cannot be improved, but that doing so is likely to have only marginal effects, and it is hard to imagine that a large new program addressing these same incentives and barriers would dramatically move the needle in the way that the TTW legislation envisioned. Instead, significant changes in beneficiary work activity would seem to require structural changes to the disability program rules that would change beneficiary incentives for work.
Still, this analysis shows that TTW has had some significant positive outcomes. It has improved choice and induced more beneficiaries to try to improve their lives with work. TTW employment services have produced definitive improvements in earnings, STW status, and BFW, at least for DI beneficiaries who are served by ENs; it likely had similar effects for SVRA clients as well. At a minimum, these benefit reductions offset some employment service costs, although further research is needed to determine the extent of the net effects. These are all important and valid achievements that SSA should build on. Although TTW has not brought the sea change its designers hoped for, there is substantial evidence that it has, and will continue to have, a significant positive effect on the lives of the people it serves.
## Appendix A: Alternative Average Cost Calculations for EN and SVRA Services
Table 6 presents estimated costs per EN and SVRA enrollee, but comparing the average costs of providing EN and SVRA services under TTW is not straightforward for many reasons, of which these two are among the more prominent:
1. Because SVRAs are also funded by block grants, SSA provider payments cover only part of their costs. In 2017, block grants funded $3.97 billion of SVRA payments, with$3.12 billion (78.7 percent) representing the non-SSA federal share and $0.85 billion (21.3 percent) representing the state share. According to our review of Case Service Reports from the Department of Education's Rehabilitation Services Administration, beneficiaries of SSA disability programs make up at least 30 percent of SVRA enrollees. Therefore, at least some of these federal funds are spent on SSA beneficiaries, even though SSA does not pay them. 2. Although ENs are allowed to choose which beneficiaries they will serve, SVRAs are required to serve anyone they are able to help. As a consequence, many SVRA clients are not expected to return to work (VR services may target functional improvement rather than employment as a goal), and these clients are not considered to be TTW participants who are likely to generate SSA reimbursement for the provider. Although SSA counts these clients as TTW participants while services are ongoing, SSA funds are highly unlikely to be used for them. For these and other reasons, SVRAs and ENs use different approaches to enrolling and serving beneficiaries, which likely drives some of the differences between EN and SVRA outcomes seen in Tables 4 and 5. For example, Table 5 indicates that SVRAs receive provider payments for only about 5 percent of the beneficiaries they enroll while ENs receive payments for 26 percent of their clients. This is significant because the different approaches SVRAs and ENs use are reflected in their costs. Some TTW administrative costs involve services that are available to all beneficiaries. These include outreach and support (for example, the telephone help line provided under the TPM contract) and training for field and regional office staff about the TTW program. Some costs, such as those for managing ticket assignments and unassignments, relate only to TTW participants. Other costs apply only to currently active EN and SVRA clients who are actively participating in TTW; examples include benefit planning queries and other questions handled at field and regional offices. Lastly, the cost of administering TTW provider payments to ENs and SVRAs relates only to TTW participants who generate payments. Because of operational differences, ENs and SVRAs have different proportions of the TTW subpopulations to which these costs apply, so simply averaging the total cost among a single subpopulation, such as all enrollees, might provide misleading comparative results. We therefore seek estimates that account for these differences, to let us compare the cost for beneficiaries who received services from one provider type with the hypothetical cost they would generate had they used the other provider type and attained similar results. We cannot sort these subpopulations into mutually exclusive categories; but summary statistics compiled from Tables 3, 4, and 5 on total enrollees, enrollees who reach STW status, and enrollees who generate provider payments can capture important differences in the SVRA and EN clientele and associated SSA costs (Table A-1). In Table A-2, we use the subpopulations and cost estimates shown in Table A-1 as the basis for illustrating five alternative methods of calculating average costs for EN and SVRA services. Each calculation method includes a caveat. Table A-1. TTW 2006 enrollee cohort and related costs Provider type Number of 2006 enrollees Costs (millions of 2016$)
Total Attained STW status as of December 2016 Generated provider payments as of December 2016 Annual administrative costs a Cumulative SSA provider payments
SVRA 135,363 25,313 7,418 6.5 108.9
EN 4,306 1,232 1,115 12.3 10.3
SOURCE: Authors' calculations using 2016 DAF and O'Leary and Roessel (2018).
NOTES: Includes DI and DI/SSI beneficiaries and SSI recipients who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who enrolled in an SVRA or an EN before or after 2006.
Includes some individuals who generated payments to both an SVRA and an EN under a single ticket assignment. These cases most likely reflect a TTW initiative called Partnership Plus that enables a client to transfer an ongoing assignment from one provider type to the other.
a. 2017 costs adjusted to 2016 dollars.
Table A-2. Alternative average cost calculations for SVRAs and ENs
Provider type Average costs (2016 $) Percentage change in SVRA block grants that would equalize SVRA and EN provider payments Caveat Total Administrative costs a Provider payments 1. Administrative costs and provider payments per enrollee SVRA 853 48 805 15 An imprecise measure because most enrollees do not generate a provider payment. It artificially increases the participation base and lowers average costs, especially for SVRAs. EN 5,248 2,856 2,392 . . . 2. Administrative costs and provider payments per STW exit SVRA 4,559 257 4,302 9 An imprecise measure because many enrollees who attain STW status do not generate a provider payment. It artificially increases the participation base and lowers average costs, especially for SVRAs. EN 18,344 9,984 8,360 . . . 3. Administrative costs and provider payments per enrollee generating payment SVRA 15,557 876 14,681 1 An imprecise measure because many administrative costs cover overall operations, not just for those who generate payments. It artificially decreases the participation base and raises average costs, especially for ENs. EN 20,269 11,031 9,238 . . . 4. Administrative costs per STW exit, provider payments per enrollee generating payment SVRA 14,937 257 14,681 3 Potentially more accurate, but this measure likely divides administrative costs by too few cases because many costs attributed to ENs are for outreach and training, which affect all enrollees. It may thus overestimate average EN costs. EN 19,221 9,984 9,238 . . . 5. Administrative costs per enrollee, provider payments per enrollee generating payment SVRA 14,729 48 14,681 -9 Potentially more accurate, but this measure may divide administrative costs by too many cases because costs are likely to be higher for enrollees generating payments. It may thus underestimate average EN costs. EN 12,094 2,856 9,238 . . . SOURCE: Authors' calculations using 2016 DAF and O'Leary and Roessel (2018). NOTES: Includes DI and DI/SSI beneficiaries and SSI recipients who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who enrolled in an SVRA or an EN before or after 2006. Includes some individuals who generated payments to both an SVRA and an EN under a single ticket assignment. These cases most likely reflect a TTW initiative called Partnership Plus that enables a client to transfer an ongoing assignment from one provider type to the other. . . . = not applicable. a. 2017 costs adjusted to 2016 dollars. Table A-2 also includes a column that addresses the fact that SVRAs receive some non-SSA funds to serve SSA program beneficiaries. With those beneficiaries accounting for at least 30 percent of SVRA clients, one might presume that SSA payments represent a similar share of total SVRA funding. Because we cannot determine the proportion of block grant funds that SVRAs use to serve SSA program beneficiaries, we instead identify the percentage of SVRA block grant funding that would equalize average EN and SVRA costs under each of the five cost calculations. For example, the total EN cost per enrollee in Table A-2, calculation 1, exceeds the SVRA cost by$4,395. If, on average, SVRAs spent this difference of $4,395 from their block grant funds on each of their 135,363 enrollees who were SSA program beneficiaries in 2016, that cost would have totaled about$595 million, which is equal to about 15 percent of the $3.97 billion in block grants they received for that year.36 Under average-cost calculation 1, if SVRAs spend more than 15 percent of their non-SSA resources on SSA program beneficiaries, then SVRA services are more expensive on average than EN services. If the figure is less than 15 percent, then SVRA services are less expensive than EN services. Among the five calculation methods, the greater the difference between the EN and SVRA average costs, the higher the percentage of block grant spending that would be needed to equalize these costs. For calculation 5, average costs are lower for ENs than for SVRAs, so the percentage becomes negative and EN services are less expensive regardless of what proportion of the non-SSA funds are spent on SSA program beneficiaries. In no case, however, does the block grant percentage approach 30 percent, so unless SVRAs consistently spend considerably less than 30 percent of their non-SSA resources on the 30 percent of clients who are SSA program beneficiaries, SVRA services are more expensive on average than EN services when all SSA payments, federal block grants, and state block grant shares are included. We explored the five alternative calculations to find an allocation method that reasonably adjusts for service intensity, such that providers whose clients require more intensive services get a higher share of the costs. The caveats in Table A-2 address potential strengths or limitations of each allocation method. In particular, the variability in the calculations shows that averaging all costs by a single group likely leads to imprecise estimates because administrative costs and provider payments are focused on different subsets of the beneficiary population. Averages per enrollee overall (calculation 1) likely underestimate both administrative costs and provider payments while averages per STW exit (calculation 2) likely overestimate administrative costs and underestimates payments. Calculations 4 and 5 provide the best comparative average cost estimates for ENs and SVRAs by using different populations for averaging administrative and payment costs. Only in calculation 5 are the average total costs lower for ENs than for SVRAs. Still, neither of these estimates is entirely accurate and we conclude the true costs likely lie somewhere between calculations 4 and 5. Regardless of calculation method for average costs, total administrative costs are greater for ENs than for SVRAs. Table A-3 looks at the types of costs that account for the differences. Administrative costs for headquarters operations and provider payments are similar for the two provider types. Regional and field office operational costs are higher for ENs because those services entail more TTW training for SSA staff and more inquiries from providers and participants than SVRA services do. TPM contract costs also diverge widely, mostly because the larger of the two components of TPM costs—for provider outreach/recruitment and timely completion of client progress reviews—is specific to EN services. The other TPM costs, for operating the TTW call center and managing ticket assignments, are higher for SVRA services because they are allotted by the relative size of the EN and SVRA participant populations. Table A-3. TTW administrative costs, by category: SVRAs and ENs, 2017 Cost category Costs (2016$) Difference (EN minus SVRA)
Total SVRA EN 2016 $Percent Total 18,835,670 6,504,129 12,331,541 5,827,413 31 Staff All 5,654,934 1,980,802 3,674,133 1,693,330 30 To administer— SSA headquarters operations and provider payments 2,939,856 1,378,063 1,561,793 183,730 6 Regional and field office operations a 2,715,078 602,739 2,112,339 1,509,600 56 TPM contract All 12,557,283 4,018,330 8,538,952 4,520,622 36 To administer— Provider outreach/recruitment and participant progress reviews 7,534,370 0 7,534,370 7,534,370 100 Ticket assignments and TTW call center operations 5,022,913 4,018,331 1,004,583 -3,013,748 -60 Printing and mailing 623,452 504,996 118,456 -386,540 -62 SOURCE: Authors' calculations using 2016 DAF and O'Leary and Roessel (2018). NOTE: Totals do not necessarily equal the sum of rounded components. a. Most of these costs are related to training and responding to inquiries from service providers and participants. Some of these costs are not strictly administrative in that they are not necessary to run the TTW program. For instance, responding to participant queries and completing timely progress reviews can respectively be viewed as broader beneficiary services and program integrity workloads that are not central to TTW operations. To estimate how “administrative” costs that are not strictly administrative in nature could affect the difference between average EN and SVRA costs, in Table A-4 we reconsider calculations 4 and 5 from Table A-2, identifying the EN costs that, if removed, would essentially eliminate the differences. Calculation 6 in Table A-4 shows that if$7 million in EN costs are not essential to TTW operations37 and we remove those costs, EN and SVRA costs equalize, even though this method adopts calculation 4's denominator (enrollees who reach STW status), which likely overstates EN average costs. This is not to say there are $7 million in EN costs that are not essential to TTW operations. TTW mandated many costs, and if$7 million of those costs were unnecessary, EN and SVRA costs would be the same.
Table A-4. Alternative average cost calculations for SVRA and EN services isolating "nonessential" administrative costs
Provider type Average costs (2016 $) Percentage change in SVRA block grants that would equalize SVRA and EN provider payments Caveat Total Administrative costs a Provider payments 6. Administrative costs per STW exit, provider payments per enrollee generating payment SVRA 14,937 257 14,681 0 Removes$7 million in TPM contract costs for EN services. Administrative costs are likely still to be overestimated because some beneficiaries who receive TTW services do not attain STW status.
EN 14,937 5,700 9,238 . . .
7. Administrative costs per enrollee, provider payments per enrollee generating payment
SVRA 14,831 150 14,681 -6 Administrative cost estimates are adjusted to try to account for different levels of TTW activity among service providers of each type.
EN 13,238 4,000 9,238 . . .
SOURCE: Authors' calculations using 2016 DAF and O'Leary and Roessel (2018).
NOTES: Includes DI and DI/SSI beneficiaries and SSI recipients who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who enrolled in an SVRA or an EN before or after 2006.
Includes some individuals who generated payments to both an SVRA and an EN under a single ticket assignment. These cases most likely reflect a TTW initiative called Partnership Plus that enables a client to transfer an ongoing assignment from one provider type to the other.
. . . = not applicable.
a. 2017 costs adjusted to 2016 dollars.
Using the methodology of calculation 5 in Table A-2 and a rough estimate of the likely distribution of administrative costs among service providers with high and low TTW activity, calculation 7 in Table A-4 shows a “best guess” of average costs and the actual provider payment amounts. Even in this scenario, costs are lower for ENs than for SVRAs (ignoring block grant resources), although the differences are smaller than those for calculation 5 in Table A-2.
This appendix shows that when we analyze TTW costs in a manner that addresses the inherent differences in how each provider type operates, it is reasonable to conclude that average EN and SVRA costs are similar. It also shows how the simple average can be misleading. Table A-5 shows the simple average costs for 2016 of $835 for SVRAs and$5,204 for ENs. If all EN clients had been served by SVRAs, total cost, as estimated using simple averages, would be $116.6 million. This suggests that moving clients from ENs to SVRAs would significantly lower costs. However, these EN clients are more successful than the average SVRA client so the SVRA cost for serving these clients would be higher than the simple SVRA average cost. If we use only SVRA costs for both EN and SVRA enrollees but compute average administrative costs using all enrollees and provider payments using only those enrollees generating payments (as in calculation 5), the estimated total cost is$129.3 million. This higher estimate adjusts for the higher success rate for EN clients and the higher costs associated with that success. This estimate is slightly lower than the combined EN and SVRA costs ($135.5 million) because it assumes that none of the$3.97 billion in non-SSA funds were used to serve these SVRA clients.
Table A-5. Alternative cost calculations for SVRA and EN services assuming SVRA costs for both provider types (in 2016 dollars)
Provider type Number of 2006 enrollees Average administrative costs a per enrollee Number of enrollees who generated a provider payment Average payment per enrollee who generated a payment Simple average costs Total costs (in millions)
Actual Assuming SVRA-level costs for both provider types
Based on simple average Based on adjusted average
TTW 139,669 135 8,533 13,671 970 135.5 116.6 129.3
SVRA 135,363 48 7,418 14,367 835 113.1 113.0 113.1
EN 4,306 2,863 1,115 9,041 5,204 22.4 3.6 16.2
SOURCE: Authors' calculations and O'Leary and Roessel (2018).
NOTE: Includes DI and DI/SSI beneficiaries and SSI recipients who were aged 18–65 in January 2006 and were on the rolls at any point in 2006. Excludes beneficiaries who enrolled in an SVRA or an EN before or after 2006.
a. 2017 costs adjusted to 2016 dollars.
Because EN and SVRA costs are so similar when properly calculated, removing either the EN or SVRA side of TTW services would not materially change the overall cost of providing employment services to SSA disability program beneficiaries. The costs would simply shift to the other provider type and the net effect would be minimal. In other words, if SSA were to stop supporting EN services, SVRA costs would go up by an amount similar to the resulting reduction in EN costs, as the ENs' former clients moved to the SVRAs. The only way for costs to decline in this case would be if the change resulted in an overall decrease in service provision.
## Notes
1 CDRs are suspended while an individual is enrolled in TTW. In the absence of this protection, CDRs generally occur every 3 to 7 years, depending on the severity of the beneficiary's disabling condition.
2 Each report consists of from one to nine individual “studies.” All of the reports and the component studies are available at https://www.ssa.gov/disabilityresearch/twe_reports.htm#twe.
3 SGA is an annually adjusted monthly earnings threshold with which SSA determines whether an individual is disabled. SSA generally regards individuals with monthly earnings at or above the SGA threshold to be capable of working at a self-sustaining level and thus not disabled. There are two thresholds depending on the nature of the disability. For 2023, the monthly SGA thresholds are $2,460 for individuals who are statutorily blind and$1,470 for other individuals.
4 Because this method relies on random groups with differing access to services, it is regarded as an experimental design.
5 For example, Dean, Dolan, and Schmidt (1999) examined SVRA case closures from 1980 and found that both men and women increased their earnings by about $5,000 in total over the 8 years after SVRA participation (our calculations based on that study's Table 6) and had “an aggregate [earnings to service cost] ratio of 2.61 for 12,031 women and 2.43 for 14,075 men.” The authors concluded “that the [SVRA] program returns roughly$2.50 for each dollar spent.”
6 Further complicating the comparison, states often do not have sufficient resources to serve all eligible individuals. When this occurs, the state's SVRAs enter “order of selection” status, under which they are required to prioritize services for individuals who are deemed by the state to have the most significant disabilities. In such circumstances, SVRAs are significantly disadvantaged relative to ENs in terms of their clients' employment prospects. We will revisit this circumstance later.
7 The number of entities that have registered as ENs is higher, but the number that actively participate in TTW at a given time has generally hovered around 600 (Prenovitz, Bardos, and O'Day 2012).
8 The TTW rollout began in 2003 but the program was not available in all states until the end of 2005.
9 A chi-square test of independence showed statistically significant increases from 2004 to 2015 in four of the five measures of work interest. Only the change in “Sees oneself working for pay in the next 2 years” was not significant.
10 Stapleton and others (2008) also found that older beneficiaries were relatively more likely to assign their ticket to an EN. Schimmel and others (2013) added that “there is no indication that the [573 percent] increase in [EN milestone-only (MO) payment-method] assignments [from 2007 to 2010] simply reflects a shift from SVRA acceptance of assignments under the traditional payment system toward more acceptance under the MO system. Indeed, the pace of growth of assignments to SVRAs under the traditional system was about the same as that of eligible beneficiaries during this period, with 0.6 percent of beneficiaries making assignments to the traditional payment system in each year from 2005 through 2010.”
11 The regression-adjusted satisfaction estimates for ENs rose from 50 percent to 68 percent. We use regression-adjusted estimates for this metric because the composition of participants before and after the implementation of the 2008 regulations differed.
12 Honeycutt and others (2015, Table 6) found that 31 of the 51 SVRAs they examined were under an order of selection. GAO (2009, Table 7) found at least one SVRA under an order of selection in 31 states in fiscal year 2008.
13 Thornton could not directly measure exits because of STW status for SVRAs. Instead, he used SSA payments to SVRAs for successful employment rehabilitation (meaning work at the SGA level for 9 months within a 12-month period) as a proxy. Such rehabilitation outcomes do not necessarily entail STW status.
14 SVRA and EN costs are structured differently, which complicates comparisons. For example, for ENs, Thornton (2012) combined the sum of the milestone payments (which SSA pays in full when a client reaches STW status) plus at least one outcome payment, plus additional outcome payments according to the proportions of clients that remain off the disability rolls over time. For SVRA costs, Thornton used average cost reimbursement paid by SSA, assuming that all clients who generate a provider reimbursement reach STW status (which is an oversimplification). It is an imperfect measure that ignores administrative costs (which are higher for ENs than for SVRAs) and provider payments funded by state VR block grants. It also excludes payments to ENs for beneficiaries who never reach STW status. Thornton accounted for both administrative costs and provider payments for EN clients who never reach STW status in calculating what it would take for EN savings to cover EN costs, but not in his comparison of EN and SVRA costs. Our Appendix A provides alternative cost estimates but its findings are similar to Thornton's.
15 We examine costs and benefits only from the perspective of the SSA disability programs. As such, BFW reflects only DI and SSI benefits and ignores potential effects on other programs such as Medicare and Medicaid. With additional data, a broader analysis of costs and benefits could be completed from the perspective of the entire federal government, state governments, and the taxpayer. Any potential TTW-related administrative costs incurred by other federal agencies and state governments, such as those involved in removing former beneficiaries from Medicaid or food stamps or processing income tax returns, would likely be negligible and probably contribute to net positive results. As such, the non-SSA effects of TTW would at worst be zero. To the extent that TTW has positive net effects beyond SSA, then the net effects on SSA are a lower bound that would imply greater net savings or lesser net costs if they were included in the analysis.
16 Because service providers typically must request reimbursement to be paid, and providers sometimes delay (or neglect) filing a request, Table 2 does not fully account for reimbursable services provided.
17 In our 2018 report, we estimated TTW administrative costs as the sum of SSA staffing and contract costs related to the TTW program. Contracting costs were provided by SSA's Office of Employment Support, the office that operates TTW, and SSA's Office of Budget.
18 Total costs in 2006 would have included tracking and payment functions for prior years' participants and recruitment activities that led to participation in subsequent years. We assume that the values for preceding and subsequent years essentially cancel each other out and avoid these computational complexities.
19 Estimating the cost of protecting TTW participants from CDRs is beyond the scope of this analysis. The Congressional Budget Office (CBO) estimated that the CDR exemption would enable SSA to save $10 million a year by conducting fewer CDRs and add$25 million a year in benefits paid to individuals who would have been found ineligible in a CDR, for a net annual cost of 15 million (CBO 1999). However, that study was overly optimistic about TTW participation, assuming that 7 percent of beneficiaries would participate, nearly triple the actual rate of less than 2.5 percent (Altshuler and others 2013). Proportionally reducing the CBO estimate to align with actual participation rates yields a net cost to SSA of4.7 million a year ($7.4 million in 2016 dollars). For the Ticket Act's 2008 amendments, SSA estimated that the cost of the CDR deferrals would be$287 million over 10 years. This translates into $320 million in 2016 dollars, or$32 million per year, which is 4.3 times the adjusted CBO estimate. More recently, the GAO found that including CDR costs took the TTW program from $2.03 billion in net savings to$529 million in net costs for the period August 2008 through December 2018 (GAO 2021, Table 7). Adjusted to 2016 dollars, GAO's estimated cost of the CDR exemption is $2.4 billion, or about$230 million per year, which is 31 times the adjusted CBO estimate and 7 times the SSA estimate. Calculating the CDR cost of TTW is clearly unsettled so we omit these estimates from our analysis.
20 We regard overpayments as a general administrative cost rather than a TTW-specific cost. Adding this cost to TTW unfairly penalizes the program for succeeding in getting beneficiaries back to work.
21 Because SVRAs are also funded by a combination of federal block grants and state funds (see https://rsa.ed.gov/about/programs/vocational-rehabilitation-state-grants), SSA pays only part of the cost of their operations. The Department of Education disburses federal grants authorized by the Rehabilitation Act of 1973, as amended by Title IV of the Workforce Innovation and Opportunity Act. The grants assist states in operating VR programs for individuals with disabilities. The federal funds are provided via a block grant formula that requires state matching funds. Currently, the federal funds provide 78.7 percent of the VR operating costs and states provide the remaining 21.3 percent. The combined funds cover both administrative and service-provision costs. In 2017, non-SSA expenditures on VR services totaled $3.97 billion, of which$3.12 billion came from federal grants. Because SSA program beneficiaries constitute no less than 30 percent of SVRA enrollees, at least some of these federal grants are spent on them.
22 For details, see https://yourtickettowork.ssa.gov/program-operations/payments.html.
23 The EN payment milestone phases have no connection with the TTW program rollout phases.
24 In our calculations, we stop attributing to the 2006 cohort any service provider payments and any BFW that result from a subsequently assigned new ticket.
25 We compared postenrollment employment outcomes for the 2006 and later enrollee cohorts. Using a 3-year postenrollment follow-up period for each cohort, we found the employment outcomes for post-2006 enrollees to be similar to, but generally lower than, those for 2006 enrollees. For example, the proportion of participants with at least 1 month of STW status in the 3 years after assignment was 11.8 percent for the 2006 cohort, 8.3 percent for the 2009 cohort, and 10.5 percent for the 2013 cohort. Similarly, average BFW were $2,328 for the 2006 cohort,$1,547 for the 2009 cohort, and $2,132 for the 2013 cohort. Because the deviations for the 2009 cohort seem to be driven largely by the Great Recession, the 2006 cohort outcomes can be regarded as reflecting TTW assignments during a relatively robust economic period. 26 Stapleton and others (2010) found that “providers received [new TTW-system] payments in approximately 40 percent of the months in which…participants were off the rolls for work during the period from 2002 through 2006.” We found similar results for SVRA participants. 27 Our analysis excludes individuals who participated in TTW only in years other than 2006. It also excludes any costs or BFW outcomes that result from a new ticket assigned after 2006 by a 2006 enrollee. We assume that costs and outcomes occurring after a subsequent ticket assignment are attributable to that subsequent assignment and not the 2006 assignment. Because we omitted individuals who participated in TTW in years other than 2006, the comparison group in our analysis—TTW nonparticipants—never participated in TTW at any time during the observation period. 28 It is also possible that some ENs receive state or non-TTW federal funding through programs such as the Workforce Investment Act. SSA does not collect such data and we have not attempted to account for funding from these potential sources. 29 Although we could have used STW status instead of TWP completion, we chose the latter because it follows 9 months of work above SGA level, thereby providing the earliest indication of work ability and serious motivation—and seriousness about work is what we most want to capture. Using TWP completion also seems akin to including the self-employed in the standard age/education Heckman framework with the selection equation based on hours of work. Positive hours of work indicate serious work effort the same way that TWP completion does, with the possibility that the effort could result in zero or even negative earnings, just as BFW can be zero despite TWP completion. 30 Technically, we do not have a true identification problem between the two stages of the Heckman model because stage one is a nonlinear probit model and stage two is a linear OLS regression. 31 In fact, ignoring selection bias attributable to unobservable work aptitude and effort results in significantly higher effects for both EN services (to$10,603) and SVRA services (from a negative value to $2,351). 32 Note that BFW continued to accrue after 2016 and thereby have since risen relative to costs. Administrative costs accrue only in the year of assignment under our cost methodology, and SSA payments to service providers beyond 2016 are very small. Although only a small proportion of beneficiaries who exit the benefit rolls remain independent permanently, their employment success raises their cumulative BFW each month until they die or reach retirement age. 33 More precisely, STW status occurs for SSI recipients when the benefit payment drops to$0 because the recipient's earnings exceed the combined general and earnings exclusion of $85, and the benefit is reduced to$0 by the $2 reduction in payment for every$1 in earning above the exclusion. Thus, for an individual with an $800 monthly SSI benefit,$1,685 in earnings in a month would put the recipient in STW status.
34 We completed a back-of-the-envelope administrative cost estimate using a combination of historical data and level-of-effort information from O'Leary and Roessel (2018) and found that 2006 costs may have been about $28 million (in 2016 dollars) rather than the$19 million we used in this analysis. However, about half of the difference ($4.5 million) is attributable to TPM contracting costs and the other half covers SSA headquarters staff time to implement and manage TTW. These costs rose from 2006 to 2012 then declined thereafter. The TTW rollout ended in 2006, new regulations were implemented in 2008, and significant changes to payment processing occurred through 2011, all of which contributed to higher administrative costs over this period. From 2012 to 2017, administrative costs declined, as new assignments rose by an average of 1.7 percent per quarter and in-use tickets increased from 392,823 to 462,000 (compared with 214,428 for 2006, based on authors' calculations using DAF data). Together, this suggests that a significant portion of the higher 2006 costs reflects startup activities that are not part of the mature TTW program, leading us to conclude that 2017 data better represent steady-state administrative costs. 35 TTW's expansion of payment models may have had less effect than was expected because the SVRA reimbursement model that predated TTW can itself be seen as outcome-based in that provider payments are predicated on the client reaching SGA in 9 of 12 months. The milestone payment model is a departure from a pure outcome system yet it functions much like reimbursement in that it pays for services based on milestones toward STW status rather than fully attaining STW status. Because outcomes did not change dramatically with the addition of EN service options and the new payment systems, the SVRA payment trigger of reaching SGA in 9 of 12 months seems to indicate the same level of success as reaching STW status under the new TTW payment rules. 36 This percentage calculation uses the number of SVRA clients that we used in calculating average administrative costs (that is, either total enrollees, the number reaching STW, or the number who generate provider payments) as specified for each average-cost calculation method in Table A-2. 37 Using figures from Table A-2, calculation 4, we subtracted the difference between EN total cost and SVRA total cost ($19,221 − $14,937, or$4,284) from the average administrative costs per STW exit for EN clients ($9,984). We then multiplied the result ($5,700) by the number of 2006 EN enrollees who attained STW status as of December 2016 in Table A-1 (1,232) to estimate \$7,022,400 in TPM contract costs for EN services.
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———. 2018b. The Social Security Administration's Programs and Projects That Assist Beneficiaries in Returning to Work. A-04-18-50600. Washington, DC: SSA, Office of the Inspector General. https://oig-files.ssa.gov/audits/full/A-04-18-50600_0.pdf.
———. 2020. DI & SSI Program Participants: Characteristics & Employment, 2015. Washington, DC: SSA. https://www.ssa.gov/policy/docs/chartbooks/di-ssi-employment/2015/index.html.
Stapleton, David C., and Gina A. Livermore. 2003. “A Conceptual Model and Evaluation Strategy for the Empirical Study of the Adequacy of Incentives in the Ticket to Work Program.” In Paying for Results in Vocational Rehabilitation: Will Provider Incentives Work for Ticket to Work?, edited by Kalman Rupp and Stephen H. Bell (71–100). Washington, DC: Urban Institute Press.
Stapleton, David, Gina Livermore, Craig Thornton, Bonnie O'Day, Robert Weathers, Krista Harrison, So O'Neil, Emily Sama Martin, David Wittenburg, and Debra Wright. 2008. Ticket to Work at the Crossroads: A Solid Foundation with an Uncertain Future. Washington, DC: Mathematica Policy Research. https://www.ssa.gov/disabilityresearch/ttw4/TTW_Rpt4_508_vol1r.pdf.
Stapleton, David, Arif Mamun, and Jeremy Page. 2013. Initial Impacts of the Ticket to Work Program for Young New Social Security Disability Awardees: Estimates Based on Randomly Assigned Mail Months. Washington, DC: Mathematica Policy Research. https://www.ssa.gov/disabilityresearch/documents/Ticket%20Impact%20Report.pdf.
Stapleton, David, Jody Schimmel, Miriam Loewenberg, and Sarah Prenovitz. 2010. Work Activity and Use of Employment Supports Under the Original Ticket to Work Regulations: Time That Beneficiaries Spend Off the Rolls Due to Work and the Payments Generated for Employment Networks. Washington, DC: Mathematica Policy Research. https://www.ssa.gov/disabilityresearch/documents/TTW5_8_LDW.pdf.
Thornton, Craig. 2012. Can the Ticket to Work Program Be Self-Financing? Washington, DC: Mathematica Policy Research. https://www.ssa.gov/disabilityresearch/documents/TTW%20Financing%20508.pdf.
Thornton, Craig, Thomas Fraker, Gina Livermore, David Stapleton, Bonnie O'Day, Tim Silva, Emily Sama Martin, John Kregel, and Debra Wright. 2006. Evaluation of the Ticket to Work Program: Implementation Experience During the Second Two Years of Operations (2003–2004). Washington, DC: Mathematica Policy Research. https://www.ssa.gov/disabilityresearch/twe_reports/twe2.htm.
Ticket to Work and Work Incentives Advisory Panel. 2007. Building on the Ticket: A New Paradigm for Investing in Economic Self-Sufficiency for People with Significant Disabilities. Final Report to the President and Congress, Year Eight of the Panel. SSA Publication No. 63-011. Washington, DC: SSA.
| 2023-03-27T08:10:00 |
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https://www.pnnl.gov/news?news%5B0%5D=research-topic%3AEmergency%20Response&news%5B1%5D=research-topic%3ANeutrino%20Physics&news%5B2%5D=research-topic%3AVehicle%20Energy%20Storage
|
# News & Media
##### Contact
21 results found
Filtered by Emergency Response, Neutrino Physics, and Vehicle Energy Storage
OCTOBER 14, 2019
News Release
### Scientists Pinpoint Cause of Harmful Dendrites and Whiskers in Lithium Batteries
Scientists have uncovered a root cause of the growth of needle-like structures—known as dendrites and whiskers—that plague lithium batteries, sometimes causing a short circuit, failure, or even a fire.
OCTOBER 4, 2019
Web Feature
### Scientists Widen the Temperature Range for Electric Car Batteries
PNNL researchers have created a chemical cocktail that could help electric cars power their way through extreme temperatures where current lithium-ion batteries don’t operate as efficiently as needed.
JULY 23, 2019
Web Feature
### Molecular Mayhem at Root of Battery Breakdown
PNNL researchers demonstrate how the excitation of oxygen atoms that contributes to better performance of a lithium-ion battery also triggers a process that leads to damage, explaining a phenomenon that has been a mystery to scientists.
JUNE 20, 2019
Web Feature
### High-Tech Damage Assessment Speeds Disaster Recovery
PNNL has developed a unique suite of tools that utilize satellite imagery to generate timely damage assessments with revealing detail.
JUNE 1, 2019
Web Feature
### A New Look at One of the Most Abundant Particles in the Universe
Researchers at PNNL are applying deep learning techniques to learn more about neutrinos, part of a worldwide network of researchers trying to understand one of the universe’s most elusive particles.
SEPTEMBER 19, 2018
Web Feature
AUGUST 2, 2018
News Release
### Smart Ideas Wanted for Grid Modernization
Plug and Play DER Challenge seeks to enable distributed energy technologies to integrate, connect and operate in harmony on the power grid.
JUNE 27, 2018
Web Feature
JUNE 26, 2018
Web Feature
### Liu Receives DOE Distinguished Achievement Award
MAY 23, 2018
Staff Accomplishment
MARCH 28, 2018
Web Feature
MARCH 27, 2018
News Release
### Research Hints at Double the Driving Range for Electric Vehicles
When it comes to the special sauce of batteries, PNNL researchers say it's all about the salt concentration.
MARCH 19, 2018
Staff Accomplishment
JANUARY 24, 2018
Web Feature
DECEMBER 5, 2017
Web Feature
### Sprenkle Discusses PNNL Energy Storage Research with U.S. Senate
NOVEMBER 13, 2017
News Release
### National Grid and Pacific Northwest National Laboratory to Collaborate on Transmission Grid Modernization and Energy Storage Research
Grid modernization, improved energy storage goals of agreement between PNNL and East Coast energy company.
OCTOBER 9, 2017
Web Feature
AUGUST 3, 2017
News Release
### World's Smallest Neutrino Detector Finds Big Physics Fingerprint
Scientists detect phenomenon in lab that occurs during neutron star formation and supernovae explosions.
JULY 19, 2017
News Release
APRIL 26, 2017
News Release
### Video Captures Bubble-blowing Battery in Action
PNNL research has created a unique video that shows oxygen bubbles inflating and later deflating inside a tiny lithium-air battery. The knowledge gained from the video could help make lithium-air batteries that are more compact, stable and
| 2019-10-16T22:31:10 |
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http://www.scstatehouse.gov/sess122_2017-2018/sj18/20180627.htm
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South Carolina General Assembly
122nd Session, 2017-2018
Journal of the Senate
NO. 74
JOURNAL
OF THE
SENATE
OF THE
STATE OF SOUTH CAROLINA
REGULAR SESSION BEGINNING TUESDAY, JANUARY 9, 2018
_________
WEDNESDAY, JUNE 27, 2018
Wednesday, June 27, 2018
(Statewide Session)
Indicates Matter Stricken
Indicates New Matter
The Senate assembled at 12:00 Noon, the hour to which it stood adjourned, and was called to order by the PRESIDENT.
A quorum being present, the proceedings were opened with a devotion by the acting Chaplain, Senator ALEXANDER as follows:
James 4:10
"Humble yourselves before the Lord and He will lift you up."
Let us pray. We come humbly before You Lord as we gather in this Senate Chamber to do the work You would have us do as the state Senate for the people of our State.
Lift us up Lord, direct our path this day, bless each Senator and all the staff as we are grateful for the opportunity to serve You. Lead, guide and direct us in this Body in the work that is before us. In thy Holy name, Amen.
The PRESIDENT called for Petitions, Memorials, Presentments of Grand Juries and such like papers.
COMMUNICATION
June 4, 2018
The Honorable Jeffrey S. Gossett
Clerk of the Senate
Suite 401, Gressette Building
Columbia, SC 29201
Dear Mr. Clerk:
With regret, I am writing you today to resign from the South Carolina Senate effective immediately.
My service of thirty-four years to the people of District 20 in the South Carolina Senate has been a tremendous personal honor. Unfortunately, I have let them down by my actions and because of that, I must resign. I will miss serving with the members and staff of the Senate and will cherish the friendships I made.
With warmest personal regards, I am
Sincerely,
John E. Courson
On motion of Senator MASSEY, with unanimous consent, the committee selection process in Rule 19 was waived and a vacancy was filled in the following manner:
Senator BENNETT fills a vacancy on the Ethics Committee.
STANDING COMMITTEE CHAIRS OF THE SENATE
AGRICULTURE AND NATURAL RESOURCES
Campbell, Paul G., Jr., Chairman
BANKING AND INSURANCE
Cromer, Ronnie W., Chairman
CORRECTIONS AND PENOLOGY
Martin, Shane R., Chairman
EDUCATION
Peeler, Harvey S., Jr., Chairman
ETHICS
Bennett, Sean M., Chairman
FINANCE
Leatherman, Hugh K., Sr., Chairman
FISH, GAME AND FORESTRY
Campsen, George E. "Chip", III, Chairman
GENERAL COMMITTEE
Shealy, Katrina F., Chairwoman
INTERSTATE COOPERATION
Leatherman, Hugh K., Sr., Chairman
INVITATIONS
Davis, Tom, Chairman
JUDICIARY
Rankin, Luke A., Chairman
LABOR, COMMERCE AND INDUSTRY
Alexander, Thomas C., Chairman
MEDICAL AFFAIRS
Verdin, Daniel B. "Danny", III Chairman
RULES
Massey, A. Shane, Chairman
TRANSPORTATION
Grooms, Lawrence K. "Larry", Chairman
MESSAGE FROM THE GOVERNOR
The following appointments were transmitted by the Honorable Henry Dargan McMaster:
Local Appointments
Reappointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Martin Ira Easler, 209 Short Street, Kingstree, SC 29556-3926
Reappointment, Abbeville County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Susan G. Gladden, 438 Highway 20, Abbeville, SC 29620-4130
Initial Appointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Randy Brice Foxworth, 209 Short Street, Kingstree, SC 29510-3926
Reappointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
William Driggers, 209 Short Street, Kingstree, SC 29556-3926
Reappointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Brian McKnight, 209 Short Street, Kingstree, SC 29556-3926
Reappointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Bryan Keith Griffin, 115 North Harvin Street, Sumter, SC 29150-4956
Reappointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Fred H. Gordon, 115 North Harvin Street, Sumter, SC 29150-4956
Reappointment, Abbeville County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Philip D. Ray, 527 Noble Dr., Abbeville, SC 29620-4115
Reappointment, Abbeville County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Carolyn Brownlee, 417 Hanover Rd., Abbeville, SC 29620-5234
Reappointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Glen Kennedy, 209 Short Street, Kingstree, SC 29556-3926
Reappointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Cecil Jackson, 115 North Harvin Street, Sumter, SC 29150-4956
Reappointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Larry Blanding, 190 East Canal Street, Sumter, SC 29150-4951
Initial Appointment, Marlboro County Part-Time Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Grover McQueen, 502 McQueen Rd., Bennettsville, SC 29512-7923
Initial Appointment, Spartanburg County Part-Time Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Chuck Bagwell, 318 Woodgrove Trace, Spartanburg, SC 29301-6432
Initial Appointment, Georgetown County Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Johnathan Guiles, 32 Genesis Dr., Georgetown, SC 29440-9398 VICE Elaine C. Elliot
Reappointment, Abbeville County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Initial Appointment, Hampton County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Tonja Alexander, P.O. Box 837, Varnville, SC 29944-0837
Initial Appointment, Marlboro County Part-Time Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Delton Powers, 107 S. Parsonage Street, Bennettsville, SC 29572 VICE Gail McInnis
Initial Appointment, Richland County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Roger Myers, 430 Old Bluff Road, Hopkins, SC 29061-9112 VICE New Seat
Initial Appointment, York County Part-Time Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Brooke Rhodes, 12088 Smithford Road, Hickory Grove, SC 29717-7765 VICE Melvin Howell
Initial Appointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Lee Anna Tindal, 190 East Canal Street, Sumter, SC 29150-4951
Leave of Absence
At 12:25 P.M., Senator NICHOLSON requested a leave of absence for Senator WILLIAMS for Wednesday, June 27, 2018 and Thursday, June 28, 2018.
Leave of Absence
At 12:25 P.M., Senator SETZLER requested a leave of absence for Senator McLEOD for the Wednesday, June 27, 2018 and Thursday, June 28, 2018.
Leave of Absence
At 12:33 P.M., Senator SETZLER requested a leave of absence for Senator SHEHEEN for the day.
INTRODUCTION OF BILLS AND RESOLUTIONS
The following were introduced:
S. 1268 (Word version) -- Senators McLeod and Setzler: A SENATE RESOLUTION TO CONGRATULATE THE CARDINAL NEWMAN SCHOOL BASEBALL TEAM, COACHES, AND SCHOOL OFFICIALS ON AN OUTSTANDING SEASON AND TO HONOR THEM FOR WINNING THE 2018 SOUTH CAROLINA INDEPENDENT SCHOOL ASSOCIATION AAA STATE BASEBALL CHAMPIONSHIP.
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S. 1269 (Word version) -- Senator Setzler: A SENATE RESOLUTION TO HONOR PAMELA P. LACKEY, PRESIDENT OF AT&T SOUTH CAROLINA, ON THE OCCASION OF HER RETIREMENT, TO EXTEND DEEP APPRECIATION FOR HER MANY YEARS OF DISTINGUISHED SERVICE TO THE RESIDENTS OF SOUTH CAROLINA, AND TO OFFER BEST WISHES FOR A SATISFYING AND REWARDING RETIREMENT.
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S. 1270 (Word version) -- Senator Scott: A SENATE RESOLUTION TO CONGRATULATE LAVERN PRIOLEAU GLOVER UPON THE OCCASION OF HER RETIREMENT, TO COMMEND HER FOR HER THIRTY-TWO YEARS OF DEDICATED PUBLIC SERVICE TO THE SOUTH CAROLINA DEPARTMENT OF TRANSPORTATION, AND TO WISH HER CONTINUED SUCCESS IN ALL HER FUTURE ENDEAVORS.
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S. 1271 (Word version) -- Senator M. B. Matthews: A SENATE RESOLUTION TO CONGRATULATE BEATRICE "BEE" FIELDS GRAHAM ON THE OCCASION OF HER ONE HUNDREDTH BIRTHDAY AND TO WISH HER A JOYOUS BIRTHDAY CELEBRATION AND MUCH HAPPINESS IN THE DAYS AHEAD.
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S. 1272 (Word version) -- Senator M. B. Matthews: A SENATE RESOLUTION TO EXPRESS THE PROFOUND SORROW OF THE MEMBERS OF THE SOUTH CAROLINA SENATE UPON THE PASSING OF HOWARD WILBUR DAVIS AND TO EXTEND THEIR DEEPEST SYMPATHY TO HIS FAMILY AND MANY FRIENDS.
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S. 1273 (Word version) -- Senator M. B. Matthews: A SENATE RESOLUTION TO CELEBRATE THE JOYOUS OCCASION OF THE ONE HUNDRED FIFTIETH ANNIVERSARY OF ST. JOHN AFRICAN METHODIST EPISCOPAL CHURCH AND TO RECOGNIZE THE CONGREGATION FOR ITS MANY YEARS OF DEDICATED SERVICE TO THE COTTAGEVILLE COMMUNITY.
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S. 1274 (Word version) -- Senator Setzler: A SENATE RESOLUTION TO CONGRATULATE DAVE SPENCE UPON THE OCCASION OF HIS RETIREMENT AS PRESIDENT OF THE SOUTHERN REGIONAL EDUCATION BOARD AND TO COMMEND MR. SPENCE AND THE SOUTHERN REGIONAL EDUCATION BOARD FOR THEIR MANY YEARS OF DEDICATED PUBLIC SERVICE TO SOUTH CAROLINA AND THE SOUTHEAST.
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S. 1275 (Word version) -- Senator Setzler: A SENATE RESOLUTION TO CONGRATULATE TURNER MEMORIAL AFRICAN METHODIST EPISCOPAL CHURCH UPON THE OCCASION OF ITS ONE HUNDRED FIFTIETH ANNIVERSARY, TO RECOGNIZE AND HONOR THE CHURCH FOR ITS DEEP HERITAGE IN WEST COLUMBIA, AND TO COMMEND ITS LEADERSHIP AND CONGREGATION FOR THEIR MANY YEARS OF SERVICE TO THE COMMUNITY.
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S. 1276 (Word version) -- Senator Alexander: A SENATE RESOLUTION TO CONGRATULATE GREGORY P. DIETTERICK UPON THE OCCASION OF HIS RETIREMENT, TO COMMEND HIM FOR HIS MANY YEARS OF DEDICATED PUBLIC SERVICE TO THE CITY OF SENECA, AND TO WISH HIM CONTINUED SUCCESS IN ALL HIS FUTURE ENDEAVORS.
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S. 1277 (Word version) -- Senators Scott and M. B. Matthews: A SENATE RESOLUTION TO EXPRESS SYMPATHY ON THE PASSING OF REVEREND DR. JAMES DANIEL RILEY, JR., AND TO OFFER SINCERE CONDOLENCES TO HIS LARGE AND LOVING FAMILY AND MANY FRIENDS.
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S. 1278 (Word version) -- Senator Scott: A SENATE RESOLUTION TO CONGRATULATE AND HONOR SHARON BURGESS MADISON ON THE OCCASION OF HER RETIREMENT ON JUNE 14, 2018, FROM THE ROLE OF DEPUTY DIRECTOR OF THE SOUTH CAROLINA DEPARTMENT OF MOTOR VEHICLES AND TO WISH HER MUCH CONTINUED HAPPINESS AND SUCCESS IN ALL HER FUTURE ENDEAVORS.
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S. 1279 (Word version) -- Senator Davis: A SENATE RESOLUTION TO CONGRATULATE THE PARRIS ISLAND YOUNG MARINES FOR GARNERING SECOND PLACE FOR THE KIKI CAMARENA AWARD IN THE 3RD DIVISION PRESENTED BY THE UNITED STATES DRUG ENFORCEMENT ADMINISTRATION AND TO DESIGNATE OCTOBER 23 TO OCTOBER 31, 2018, AS "RED RIBBON WEEK" IN SOUTH CAROLINA.
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S. 1280 (Word version) -- Senator Setzler: A JOINT RESOLUTION TO PROHIBIT THE PUBLIC SERVICE COMMISSION FROM HOLDING A HEARING ON THE MERITS FOR DOCKET IN WHICH REQUESTS WERE MADE PURSUANT TO THE BASE LOAD REVIEW ACT BEFORE NOVEMBER 1, 2018; TO REQUIRE THE PUBLIC SERVICE COMMISSION TO ISSUE AN ORDER FOR REQUESTS MADE PURSUANT TO THE BASE LOAD REVIEW ACT BY DECEMBER 21, 2018; TO CLARIFY THAT A FINAL DETERMINATION OF MATTERS OF THESE REQUESTS SHALL OCCUR EARLIER THAN ESTABLISHED IN THIS JOINT RESOLUTION; AND TO TEMPORARILY SUSPEND ANY STATUTE IN TITLE 58 THAT CONFLICTS WITH THE PROVISION OF THIS RESOLUTION FOR PURPOSES OF UTILITY RATES FOR MATTERS RELATED TO THE V.C. SUMMER NUCLEAR REACTOR UNITS 2 AND 3.
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Read the first time and referred to the Committee on Judiciary.
S. 1281 (Word version) -- Senator Massey: A JOINT RESOLUTION TO PROHIBIT THE PUBLIC SERVICE COMMISSION HOLDING A HEARING ON THE MERITS FOR REQUESTS MADE PURSUANT TO THE BASE LOAD REVIEW ACT UNTIL MARCH 1, 2019 AND TO REQUIRE A FINAL ORDER TO BE ISSUED SIX WEEKS AFTER THE CONCLUSION OF A HEARING ON THE MERITS; TO PROVIDE FOR DISCOVERY REQUEST DISPUTES; TO CLARIFY THAT THE COMMISSION'S FAILURE TO ISSUE A FINAL ORDER IN THE TIME PERIOD PRESCRIBED BY THIS JOINT RESOLUTION DOES NOT CONSTITUTE APPROVAL BY THE COMMISSION NOR MAY THE UTILITY PUT INTO EFFECT ITS REQUESTED RATE CHANGE; AND TO SUSPEND ANY CONFLICTING STATUTES IN TITLE 58 FOR PURPOSES OF UTILITY RATES RELATED TO V.C. SUMMER NUCLEAR REACTOR UNITS 2 & 3.
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Read the first time and referred to the Committee on Judiciary.
S. 1282 (Word version) -- Senator Sabb: A SENATE RESOLUTION TO RECOGNIZE JULY 21, 2018 AS "BISHOP EDWARD BLAIN, II DAY" IN SOUTH CAROLINA, TO COMMEND BISHOP BLAIN FOR HIS MANY YEARS OF DEDICATED SERVICE AS FOUNDER AND SENIOR BISHOP OF THE GLORIOUS UNITED PENTECOSTAL CHURCH OF GOD, INC., AND TO CONGRATULATE HIM ON THE OCCASION OF HIS NINETY-FOURTH BIRTHDAY.
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S. 1283 (Word version) -- Senator Sabb: A SENATE RESOLUTION TO CONGRATULATE THE HONORABLE JAMES E. DOSTER, JR. UPON THE OCCASION OF HIS RETIREMENT FROM THE WILLIAMSBURG COUNTY SUMMARY COURT, TO COMMEND HIM FOR HIS MANY YEARS OF DEDICATED PUBLIC SERVICE TO WILLIAMSBURG COUNTY, AND TO WISH HIM CONTINUED SUCCESS IN ALL HIS FUTURE ENDEAVORS.
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S. 1284 (Word version) -- Senator Corbin: A SENATE RESOLUTION TO EXPRESS THE PROFOUND SORROW OF THE MEMBERS OF THE SOUTH CAROLINA SENATE UPON THE UNTIMELY PASSING OF ISABELLA "BELLA" MUNTEAN AND TO EXTEND THEIR DEEPEST SYMPATHY TO HER FAMILY AND MANY FRIENDS.
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S. 1285 (Word version) -- Senator Jackson: A SENATE RESOLUTION TO CONGRATULATE AND COMMEND THE UNITED FAMILY REUNION ON ITS LAUDABLE EFFORTS TO RECOUNT THE HISTORY AND CONTRIBUTIONS OF ENSLAVED AFRICAN AMERICANS AND THEIR DESCENDANTS OF THE LANG SYNE, OAKLAND, GOSHEN, SANDY LAWN, AND TRUE BLUE PLANTATIONS AT FORT MOTTE IN CALHOUN COUNTY AND RECORD IT FOR FUTURE GENERATIONS AS A LESSON IN THE POWER OF KNOWLEDGE AND FAITH IN FORMING A STRONG COMMUNITY AND STATE.
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HOUSE CONCURRENCE
S. 1267 (Word version) -- Senator Cromer: A CONCURRENT RESOLUTION TO CONGRATULATE THE MID-CAROLINA MIDDLE SCHOOL ACADEMIC TEAM, COACHES, AND SCHOOL OFFICIALS ON WINNING THE 2018 SOUTH CAROLINA STATE CHAMPIONSHIP OF ACADEMICS.
Returned with concurrence.
THE SENATE PROCEEDED TO A CONSIDERATION OF REPORTS OF COMMITTEES OF CONFERENCE AND FREE CONFERENCE.
H. 4931--REPORT OF THE
H. 4931 (Word version) -- Reps. Elliott, Alexander, Simrill, Stringer, West, Allison, Henderson, G.R. Smith, Burns, Trantham, Hamilton, Bannister, Putnam, Robinson-Simpson, Chumley, Taylor, Douglas, Knight, Dillard and Blackwell: A BILL TO AMEND SECTION 59-103-15, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE MISSIONS AND FOCUSES OF INSTITUTIONS OF HIGHER LEARNING, SO AS TO AUTHORIZE AN APPLIED BACCALAUREATE IN MANUFACTURING DEGREE IF STATE FUNDS ARE NOT APPROPRIATED FOR THE OPERATIONS OF THE DEGREE PROGRAM.
On motion of Senator TURNER, with unanimous consent, the Report of the Committee of Conference was taken up for immediate consideration.
Senator TURNER spoke on the report.
The question then was adoption of the Report of Committee of Conference.
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 39; Nays 2
AYES
Alexander Allen Bennett
Campbell Cash Climer
Corbin Cromer Davis
Fanning Gambrell Goldfinch
Gregory Grooms Hembree
Hutto Jackson Johnson
Kimpson Leatherman Malloy
Martin Matthews, Margie McElveen
Nicholson Peeler Rankin
Reese Rice Sabb
Scott Senn Setzler
Shealy Talley Timmons
Turner Verdin Young
Total--39
NAYS
Campsen Massey
Total--2
The Committee of Conference Committee was adopted as follows:
H. 4931 -- Conference Report
The General Assembly, Columbia, S.C., June 26, 2018
The COMMITTEE OF CONFERENCE, to whom was referred:
H. 4931 (Word version) -- Reps. Elliott, Alexander, Simrill, Stringer, West, Allison, Henderson, G.R. Smith, Burns, Trantham, Hamilton, Bannister, Putnam, Robinson-Simpson, Chumley, Taylor, Douglas, Knight, Dillard and Blackwell: A BILL TO AMEND SECTION 59-103-15, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE MISSIONS AND FOCUSES OF INSTITUTIONS OF HIGHER LEARNING, SO AS TO AUTHORIZE AN APPLIED BACCALAUREATE IN MANUFACTURING DEGREE IF STATE FUNDS ARE NOT APPROPRIATED FOR THE OPERATIONS OF THE DEGREE PROGRAM.
Beg leave to report that they have duly and carefully considered the same and recommend:
That the same do pass with the following amendments: (Reference is to Printer's Version 05/09/18-S.)
Amend the bill, as and if amended, by striking all after the enacting words and inserting:
/ SECTION 1. Section 59-103-15 of the 1976 Code is further amended to read:
"Section 59-103-15. (A)(1) The General Assembly has determined that the mission for higher education in South Carolina is to be a global leader in providing a coordinated, comprehensive system of excellence in education by providing instruction, research, and life-long learning opportunities which are focused on economic development and benefit the State of South Carolina.
(2) The goals to be achieved through this mission are:
(b) affordable and accessible education;
(c) instructional excellence;
(d) coordination and cooperation with public education;
(e) cooperation among the General Assembly, Commission on Higher Education, Council of Presidents of State Institutions, institutions of higher learning, and the business community;
(f) economic growth;
(g) clearly defined missions.
(B) The General Assembly has determined that the primary mission or focus for each type of institution of higher learning or other post-secondary school in this State is as follows:
(1) Research institutions
(a) college-level baccalaureate education, master's, professional, and doctor of philosophy degrees which lead to continued education or employment;
(b) research through the use of government, corporate, nonprofit-organization grants, or state resources, or both;
(c) public service to the State and the local community;
(2) Four-year colleges and universities
(a) college-level baccalaureate education and selected master's degrees which lead to employment or continued education, or both, except for doctoral degrees currently being offered;
(b) bachelor of science degree in Mechanical Engineering approved by the Commission on Higher Education at South Carolina State University;
(c) bachelor of science degree in Electrical Engineering approved by the Commission on Higher Education at South Carolina State University;
(d) doctoral degree in Marine Science approved by the Commission on Higher Education;
(e) subject to subsection (C), doctoral degree in Nursing Practice approved by the Commission on Higher Education at Francis Marion University;
(f) subject to subsection (C), doctoral degree in Nursing Practice approved by the Commission on Higher Education at the University of South Carolina Aiken;
(g) subject to subsection (C), doctor of philosophy degree in Education Administration approved by the Commission on Higher Education at Coastal Carolina University;
(h) subject to subsection (C), doctor of philosophy degree in Computer and Information Science approved by the Commission on Higher Education at the College of Charleston;
(i) limited and specialized research;
(j) public service to the State and the local community;
(3) Two-year institutions - branches of the University of South Carolina
(a) college-level pre-baccalaureate education necessary to confer associates degrees which lead to continued education at a four-year or research institution;
(b) public service to the State and the local community;
(4) State technical and comprehensive education system
(a) all post-secondary vocational, technical, and occupational diploma and associate degree programs leading directly to employment or maintenance of employment and associate degree programs which enable students to gain access to other post-secondary education;
(b) up-to-date and appropriate occupational and technical training for adults;
(c) special school programs that provide training for prospective employees for prospective and existing industry in order to enhance the economic development of South Carolina;
(d) public service to the State and the local community;
(e) continue to remain technical, vocational, or occupational colleges with a mission as stated in item (4) and primarily focused on technical education and the economic development of the State;
(f) subject to subsection (C), an Applied Baccalaureate in Advanced Manufacturing Technology degree approved first by the Board for Technical and Comprehensive Education and then the Commission on Higher Education.
(C) Notwithstanding subsection (B), the doctoral degrees set forth in subsection (B)(2)(c), (d), and (e), (f), (g), and (h), and subsection (B)(4)(f) are only allowed so long as new state general funds are not appropriated for the operations of the degree program."
SECTION 2. This act takes effect upon approval by the Governor. /
Amend title to conform.
/s/Sen. Clarence Ross Turner, III /s/Rep. Bill Taylor
/s/Sen. Tom Young, Jr. /s/Rep. Jason Thomas Elliott
/s/Sen. Karl B. Allen /s/Rep. Terry Alexander
On Part of the Senate. On Part of the House.
, and a message was sent to the House accordingly.
Message from the House
Columbia, S.C., June 27, 2018
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has adopted the Report of the Committee of Conference on:
H. 4931 (Word version) -- Reps. Elliott, Alexander, Simrill, Stringer, West, Allison, Henderson, G.R. Smith, Burns, Trantham, Hamilton, Bannister, Putnam, Robinson-Simpson, Chumley, Taylor, Douglas, Knight, Dillard and Blackwell: A BILL TO AMEND SECTION 59-103-15, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE MISSIONS AND FOCUSES OF INSTITUTIONS OF HIGHER LEARNING, SO AS TO AUTHORIZE AN APPLIED BACCALAUREATE IN MANUFACTURING DEGREE IF STATE FUNDS ARE NOT APPROPRIATED FOR THE OPERATIONS OF THE DEGREE PROGRAM.
Very respectfully,
Speaker of the House
H. 4931--REPORT OF COMMITTEE OF CONFERENCE
ENROLLED FOR RATIFICATION
H. 4931 (Word version) -- Reps. Elliott, Alexander, Simrill, Stringer, West, Allison, Henderson, G.R. Smith, Burns, Trantham, Hamilton, Bannister, Putnam, Robinson-Simpson, Chumley, Taylor, Douglas, Knight, Dillard and Blackwell: A BILL TO AMEND SECTION 59-103-15, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE MISSIONS AND FOCUSES OF INSTITUTIONS OF HIGHER LEARNING, SO AS TO AUTHORIZE AN APPLIED BACCALAUREATE IN MANUFACTURING DEGREE IF STATE FUNDS ARE NOT APPROPRIATED FOR THE OPERATIONS OF THE DEGREE PROGRAM.
The Report of the Committee of Conference having been adopted by both Houses, ordered that the title be changed to that of an Act, and the Act enrolled for Ratification.
A message was sent to the House accordingly.
S. 954--REPORT OF THE
S. 954 (Word version) -- Senators Leatherman, Setzler, Massey and Fanning: A JOINT RESOLUTION TO PROVIDE FOR AN EXPERIMENTAL RATE FOR CUSTOMERS OF A PUBLIC UTILITY WHO ARE PAYING COSTS ASSOCIATED WITH THE BASE LOAD REVIEW ACT; TO PROHIBIT THE PUBLIC SERVICE COMMISSION FROM HOLDING A HEARING ON THE MERITS FOR A MATTER RELATED TO THE BASE LOAD REVIEW ACT BEFORE NOVEMBER 1, 2018, BUT MUST ISSUE A FINAL ORDER ON THE MERITS BY DECEMBER 21, 2018; AND TO SUSPEND PROVISIONS IN TITLE 58 THAT ARE IN CONFLICT WITH THE PROVISIONS OF THIS JOINT RESOLUTION FOR MATTERS RELATED TO THE V.C. SUMMER NUCLEAR REACTOR UNITS 2 AND 3 UNTIL THE PUBLIC SERVICE COMMISSION ISSUES ITS FINAL ORDER IN THE MATTER.
On motion of Senator SETZLER, with unanimous consent, the Report of the Committee of Conference was taken up for immediate consideration.
Senator SETZLER spoke on the report.
The question then was adoption of the Report of Committee of Conference.
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 41; Nays 0
AYES
Alexander Allen Bennett
Campbell Campsen Cash
Climer Corbin Cromer
Davis Fanning Gambrell
Goldfinch Gregory Grooms
Hembree Hutto Jackson
Johnson Leatherman Malloy
Martin Massey Matthews, John
Matthews, Margie McElveen Nicholson
Peeler Rankin Reese
Rice Sabb Scott
Senn Setzler Shealy
Talley Timmons Turner
Verdin Young
Total--41
NAYS
Total--0
The Committee of Conference Committee was adopted as follows:
S. 954 -- Conference Report
The General Assembly, Columbia, S.C., June 27, 2018
The COMMITTEE OF CONFERENCE, to whom was referred:
S. 954 (Word version) -- Senators Leatherman, Setzler, Massey and Fanning: A JOINT RESOLUTION TO PROVIDE FOR AN EXPERIMENTAL RATE FOR CUSTOMERS OF A PUBLIC UTILITY WHO ARE PAYING COSTS ASSOCIATED WITH THE BASE LOAD REVIEW ACT; TO PROHIBIT THE PUBLIC SERVICE COMMISSION FROM HOLDING A HEARING ON THE MERITS FOR A MATTER RELATED TO THE BASE LOAD REVIEW ACT BEFORE NOVEMBER 1, 2018, BUT MUST ISSUE A FINAL ORDER ON THE MERITS BY DECEMBER 21, 2018; AND TO SUSPEND PROVISIONS IN TITLE 58 THAT ARE IN CONFLICT WITH THE PROVISIONS OF THIS JOINT RESOLUTION FOR MATTERS RELATED TO THE V.C. SUMMER NUCLEAR REACTOR UNITS 2 AND 3 UNTIL THE PUBLIC SERVICE COMMISSION ISSUES ITS FINAL ORDER IN THE MATTER.
Beg leave to report that they have duly and carefully considered the same and recommend:
That the same do pass with the following amendments: (Reference is to Printer's Version 04/19/18.)
/ Amend the joint resolution, as and if amended, by striking all after the enacting words and inserting:
Whereas, while SCANA has taken steps to reduce its own costs related to the abandoned Project, such as obtaining a guaranty settlement from Toshiba in the amount of approximately \$1.2 billion for SCANA's ownership interests, and also has received benefits from the recent federal tax code amendments, its customers' rates continue to reflect 100% of authorized Project costs prior to abandonment; and
Whereas, the General Assembly recognizes that SCANA, as a corporate entity, has legal rights and remedies that must be considered and respected throughout the process of resolving cost recovery issues for the abandoned Project, yet believes that recognition of SCANA's legal rights and remedies does not require that SCANA customers continue to pay 100% of the rates previously authorized by the Commission when the Project was expected, upon completion, to provide valuable services to the customers; and
Whereas, the General Assembly recognizes the need for adequate discovery by all parties, and therefore is extending the time period for the Public Service Commission to issue its final order in this matter; and
Whereas, the General Assembly passed the BLRA in 2007 for the explicit purpose of providing "recovery of the prudently incurred costs associated with new base load plants...when constructed by investor-owned electrical utilities, while at the same time protecting customers of investor-owned electrical utilities from responsibility for imprudent financial obligations or costs"; and
Whereas, the General Assembly, with the passage of the BLRA in 2007 did not intend to, and could not, overrule a fundamental regulatory principal for utility rate-making that rates must be just and reasonable, the fundamental regulatory principal codified in South Carolina Code Section 58-27-810; and
Whereas, the General Assembly is concerned that the rates that SCANA customers are currently paying are unjust and unreasonable; and
Whereas, Section 1, Article IX of the Constitution of this State vests the General Assembly with authority to regulate investor-owned utilities in order to protect the public interest; and
Whereas, based upon information identified in this Joint Resolution, along with other information recently made available to the South Carolina House of Representative and the South Carolina Senate, the General Assembly finds that serious questions have arisen regarding the prudency of incurred costs that have led to rate increases pursuant to the BLRA for the abandoned Project, including SCANA's apparent failure to avoid or minimize costs that should have been avoided or minimized since at least 2011; and
Whereas, the General Assembly recognizes the protections provided by the Constitutions of the United States and the State of South Carolina, and has no desire or intention to set a rate that is unjust, unreasonable, or confiscatory, nor does it intend to jeopardize SCANA's ability to satisfy bond payment obligations associated with the V.C. Summer nuclear units 2 and 3; and
Whereas, the General Assembly also believes it is in the public interest of all its citizens, both private citizens and corporate, to rely upon incentives offered by the General Assembly to encourage growth in South Carolina, however, this reliance should be predicated upon a good faith effort to comply with all terms of any incentives so that noncompliance or misrepresentation in order to obtain offered incentives are not unfairly born by South Carolina's citizens;
Now, therefore,
Be it enacted by the General Assembly of the State of South Carolina:
SECTION 1. The Public Service Commission shall not hold a hearing on the merits before November 1, 2018, for a docket in which requests were made pursuant to the Base Load Review Act; however, the Public Service Commission may hold an administrative or procedural hearing for such a docket prior to a hearing on the merits. The Public Service Commission must issue a final order on the merits for a docket in which requests were made pursuant to the Base Load Review Act no later than December 21, 2018.
SECTION 2. No final determination of matters described in this joint resolution, whether by a final order issued by the Public Service Commission or by operation of law, shall occur earlier than the time period prescribed in SECTION 1. The Public Service Commission's failure to issue a final order prior to the time period established in this joint resolution shall not constitute approval by the Public Service Commission and a utility must not put into effect the change in rates it requested in its schedule.
SECTION 3. Any statute in Title 58 in conflict with the provisions of this joint resolution are suspended for purposes of the utility rates for matters related to V.C. Summer Nuclear Reactor Units 2 and 3 at Jenkinsville, South Carolina. This suspension remains in effect until the Public Service Commission issues its final order in this matter.
SECTION 4. If any provision of this joint resolution is held or determined to be unconstitutional, invalid, or otherwise unenforceable by a court of competent jurisdiction, it is the intention of the General Assembly that the provision is severable from the remaining provisions of this joint resolution and that the holding does not invalidate or render unenforceable another provision of this joint resolution.
SECTION 5. This joint resolution takes effect upon approval by the Governor. /
Amend title to conform.
/s/Sen. Nikki G. Setzler /s/Rep. Peter M. McCoy, Jr.
/s/Sen. Luke A. Rankin, Sr. /s/Rep. Kirkman Finlay, III
/s/Sen. A. Shane Massey /s/Rep. J. Todd Rutherford
On Part of the Senate. On Part of the House.
, and a message was sent to the House accordingly.
Message from the House
Columbia, S.C., June 27, 2018
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has adopted the Report of the Committee of Conference on:
S. 954 (Word version) -- Senators Leatherman, Setzler, Massey and Fanning: A JOINT RESOLUTION TO PROVIDE FOR AN EXPERIMENTAL RATE FOR CUSTOMERS OF A PUBLIC UTILITY WHO ARE PAYING COSTS ASSOCIATED WITH THE BASE LOAD REVIEW ACT; TO PROHIBIT THE PUBLIC SERVICE COMMISSION FROM HOLDING A HEARING ON THE MERITS FOR A MATTER RELATED TO THE BASE LOAD REVIEW ACT BEFORE NOVEMBER 1, 2018, BUT MUST ISSUE A FINAL ORDER ON THE MERITS BY DECEMBER 21, 2018; AND TO SUSPEND PROVISIONS IN TITLE 58 THAT ARE IN CONFLICT WITH THE PROVISIONS OF THIS JOINT RESOLUTION FOR MATTERS RELATED TO THE V.C. SUMMER NUCLEAR REACTOR UNITS 2 AND 3 UNTIL THE PUBLIC SERVICE COMMISSION ISSUES ITS FINAL ORDER IN THE MATTER.
Very respectfully,
Speaker of the House
Message from the House
Columbia, S.C., June 27, 2018
Mr. President and Senators:
The House respectfully informs your Honorable Body that the Report of the Committee of Conference having been adopted by both Houses, and this Bill having been read three times in each House, it was ordered that the title thereof be changed to that of an Act and that it be enrolled for Ratification:
S. 954 (Word version) -- Senators Leatherman, Setzler, Massey and Fanning: A JOINT RESOLUTION TO PROVIDE FOR AN EXPERIMENTAL RATE FOR CUSTOMERS OF A PUBLIC UTILITY WHO ARE PAYING COSTS ASSOCIATED WITH THE BASE LOAD REVIEW ACT; TO PROHIBIT THE PUBLIC SERVICE COMMISSION FROM HOLDING A HEARING ON THE MERITS FOR A MATTER RELATED TO THE BASE LOAD REVIEW ACT BEFORE NOVEMBER 1, 2018, BUT MUST ISSUE A FINAL ORDER ON THE MERITS BY DECEMBER 21, 2018; AND TO SUSPEND PROVISIONS IN TITLE 58 THAT ARE IN CONFLICT WITH THE PROVISIONS OF THIS JOINT RESOLUTION FOR MATTERS RELATED TO THE V.C. SUMMER NUCLEAR REACTOR UNITS 2 AND 3 UNTIL THE PUBLIC SERVICE COMMISSION ISSUES ITS FINAL ORDER IN THE MATTER.
Very respectfully,
Speaker of the House
On motion of Senator REESE, with unanimous consent, Senators TALLY, GROOMS and REESE were granted leave to attend a conference committee meeting and were granted leave to vote from the balcony.
S. 709--REPORT OF THE
S. 709 (Word version) -- Senator Hembree: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING ARTICLE 4 TO CHAPTER 23, TITLE 59 SO AS TO REQUIRE FIRE AND SAFETY INSPECTIONS AT ALL PUBLIC SCHOOL FACILITIES AT LEAST ANNUALLY, AND TO PROVIDE RELATED POWERS AND DUTIES OF THE OFFICE OF THE STATE FIRE MARSHAL.
On motion of Senator NICHOLSON, with unanimous consent, the Report of the Committee of Conference was taken up for immediate consideration.
Senator NICHOLSON spoke on the report.
The question then was adoption of the Report of Committee of Conference.
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 40; Nays 1
AYES
Alexander Bennett Campbell
Campsen Cash Climer
Cromer Davis Fanning
Gambrell Goldfinch Gregory
Grooms Hembree Hutto
Jackson Johnson Kimpson
Leatherman Malloy Martin
Massey Matthews, John Matthews, Margie
McElveen Nicholson Peeler
Rankin Reese Rice
Sabb Scott Senn
Setzler Shealy Talley
Timmons Turner Verdin
Young
Total--40
NAYS
Corbin
Total--1
The Committee of Conference Committee was adopted as follows:
S. 709 -- Conference Report
The General Assembly, Columbia, S.C., June 27, 2018
The COMMITTEE OF CONFERENCE, to whom was referred:
S. 709 (Word version) -- Senator Hembree: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING ARTICLE 4 TO CHAPTER 23, TITLE 59 SO AS TO REQUIRE FIRE AND SAFETY INSPECTIONS AT ALL PUBLIC SCHOOL FACILITIES AT LEAST ANNUALLY, AND TO PROVIDE RELATED POWERS AND DUTIES OF THE OFFICE OF THE STATE FIRE MARSHAL.
Beg leave to report that they have duly and carefully considered the same and recommend:
That the same do pass with the following amendments: (Reference is to Printer's Version 04/26/18-H.)
Amend the bill, as and if amended, by striking all after the enacting words and inserting:
/ SECTION 1. Chapter 17, Title 59 of the 1976 Code is amended by adding:
"Section 59-17-160. (A) Prior to the beginning of the 2019-2020 School Year, the State Department of Education and the Office of the State Fire Marshal shall collaborate and develop model fire and safety policies and program guidelines that must be made available to each school district and charter school in the state. The provisions of this section do not apply to charter schools whose instruction is primarily delivered online.
(B) Each school district board of trustees and the governing body of each charter school shall adopt a policy and program for school facility fire and safety, including inspections, before the beginning of the 2020-2021 School Year. The policy and program must:
(1) be adopted in open meetings in which the public may provide comment on the terms of the policies and programs;
(2) include routine self-assessments; and
(3) be published on the district's or charter school's Internet website in a prominent location that is easily accessible by the public.
(C) Prior to July 1, 2021, each district and charter school shall submit its fire and safety policy and program to the Office of the State Fire Marshal and the State Department of Education. The office and department shall collaborate in the review of the school policies and programs. Within one hundred twenty days of the receipt of a policy or program, the office and department must jointly provide written comments to the district on how the policies and programs may be improved.
(D) Local school district boards of trustees and charter school governing bodies may request technical assistance in the development of fire and safety policies and programs."
SECTION 2. Section 59-63-910 of the 1976 Code is amended to read:
"Section 59-63-910. (A) All teachers or superintendents in charge of the schools of the State which are supported in whole or in part by taxation public schools, including charter schools whose instruction is not primarily delivered online, shall conduct fire, active shooter/intruder, and severe weather/earthquake drills at least once each month. Any teacher or superintendent failing to observe the provisions of this section shall be fined not less than ten dollars nor more than twenty-five dollars for each offense. Such fine shall be deducted from his salary and turned over to the county treasurer for ordinary county purposes Within each school year, schools must conduct at least two fire drills, two active shooter/intruder drills, and two severe weather/earthquake drills, with at least one of each drill conducted each semester.
(B) Before August 1, 2018, the State Department of Education and the South Carolina Law Enforcement Division shall develop guidelines for the conduct of active shooter/intruder training required in this section, and developmentally appropriate training materials. The department and the State Law Enforcement Division must consult with school-employed mental health professionals and the State Fire Marshal in creating and updating the guidelines. These guidelines must be included in annual teacher collegial development required by Section 59-1-425(A)."
SECTION 3. Section 59-63-920 of the 1976 Code is amended to read:
"Section 59-63-920. The principal or supervising teacher charter school leader of each school shall indicate on his monthly pay voucher whether he has complied comply with the requirements of Section 59-63-910, and should it appear that he has failed to do so the superintendent of education shall deduct from that teacher's salary the minimum fine for the first offense and the maximum fine for each following offense and document their compliance."
SECTION 4. Section 59-63-930 of the 1976 Code is repealed.
SECTION 5. Article 9, Chapter 63, Title 59 of the 1976 Code is redesignated "Safety and Security Drills."
SECTION 6. This act takes effect upon approval by the Governor. /
Amend title to conform.
/s/Sen. Floyd Nicholson /s/Rep. Merita Ann Allison
/s/Sen. Greg Hembree /s/Rep. R. Raye Felder
/s/Sen. Clarence Ross Turner, III /s/Rep. Marvin R. Pendarvis
On Part of the Senate. On Part of the House.
, and a message was sent to the House accordingly.
Message from the House
Columbia, S.C., June 27, 2018
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has adopted the Report of the Committee of Conference on:
S. 709 (Word version) -- Senator Hembree: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING ARTICLE 4 TO CHAPTER 23, TITLE 59 SO AS TO REQUIRE FIRE AND SAFETY INSPECTIONS AT ALL PUBLIC SCHOOL FACILITIES AT LEAST ANNUALLY, AND TO PROVIDE RELATED POWERS AND DUTIES OF THE OFFICE OF THE STATE FIRE MARSHAL.
Very respectfully,
Speaker of the House
S. 709--REPORT OF COMMITTEE OF CONFERENCE
ENROLLED FOR RATIFICATION
S. 709 (Word version) -- Senator Hembree: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING ARTICLE 4 TO CHAPTER 23, TITLE 59 SO AS TO REQUIRE FIRE AND SAFETY INSPECTIONS AT ALL PUBLIC SCHOOL FACILITIES AT LEAST ANNUALLY, AND TO PROVIDE RELATED POWERS AND DUTIES OF THE OFFICE OF THE STATE FIRE MARSHAL.
The Report of the Committee of Conference having been adopted by both Houses, ordered that the title be changed to that of an Act, and the Act enrolled for Ratification.
A message was sent to the House accordingly.
H. 4375--REPORT OF THE
H. 4375 (Word version) -- Reps. McCoy, Ott, Lucas, Anderson, Ballentine, Blackwell, Caskey, Crawford, Crosby, Davis, Finlay, Forrester, Gilliard, Hardee, Henegan, Hixon, Mack, Pope, Rutherford, J.E. Smith, Sandifer, Stavrinakis, Erickson, Huggins, W. Newton, Bales, Young, McEachern, Clary, Tallon, Brown, Fry, Robinson-Simpson, V.S. Moss, Clyburn, Martin, Magnuson, Bennett, Arrington, Daning, Weeks, Henderson and Govan: A BILL TO AMEND SECTION 58-33-220, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO DEFINITIONS UNDER THE BASE LOAD REVIEW ACT, SO AS TO ADD CERTAIN DEFINITIONS; TO REPEAL ARTICLES 4 AND 5, CHAPTER 33, TITLE 58, RELATING TO THE BASE LOAD REVIEW ACT, AND TO PROVIDE A SPECIFIC EXCEPTION TO THIS REPEAL; BY ADDING CHAPTER 34 TO TITLE 58 SO AS TO PROVIDE FOR THE MANNER IN WHICH AND PROCEDURES UNDER WHICH ELECTRICITY RATES FOR CERTAIN RATEPAYERS WHO ARE PAYING ADDITIONAL CHARGES UNDER THE BASE LOAD REVIEW ACT FOR THE CONSTRUCTION OF NUCLEAR PLANTS OR PROJECTS SHALL BE REVISED AND DETERMINED; AND TO PROVIDE FOR PROCEDURES AND PROVISIONS OF LAW WHICH APPLY AND DO NOT APPLY IN REGARD TO THE ADJUSTMENT OF ELECTRICITY RATES AS PROVIDED BY CHAPTER 34.
On motion of Senator SETZLER, with unanimous consent, the Report of the Committee of Conference was taken up for immediate consideration.
Senator SETZLER spoke on the report.
Senator MASSEY spoke on the report.
ACTING PRESIDENT PRESIDES
Senator HUTTO assumed the Chair.
Senator RANKIN spoke on the report.
PRESIDENT PRESIDES
The PRESIDENT assumed the Chair.
Senator HUTTO spoke on the report.
ACTING PRESIDENT PRESIDES
Senator GOLDFINCH assumed the Chair.
ACTING PRESIDENT PRESIDES
Senator CROMER assumed the Chair.
Point of Quorum
At 2:55 P.M., Senator MALLOY made the point that a quorum was not present. It was ascertained that a quorum was present. The Senate resumed.
Objection
Senator MALLOY asked unanimous consent to make a motion to carry over the Bill, with Senator HUTTO retaining the floor.
Senator LEATHERMAN objected.
Senator HUTTO resumed speaking on the conference report.
On motion of Senator CAMPSEN, with unanimous consent, Senators SCOTT, YOUNG and CAMPSEN were granted leave to attend a conference committee meeting and were granted leave to vote from the balcony.
Senator HUTTO moved to carry over the conference report.
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 0; Nays 40
AYES
Total--0
NAYS
Alexander Allen Bennett
Campbell Campsen Cash
Climer Corbin Cromer
Davis Fanning Gambrell
Goldfinch Gregory Grooms
Hembree Jackson Johnson
Kimpson Leatherman Malloy
Massey Matthews, John Matthews, Margie
McElveen Nicholson Peeler
Rankin Reese Rice
Sabb Scott Senn
Setzler Shealy Talley
Timmons Turner Verdin
Young
Total--40
The Senate refused to carry over the conference report.
The question then being the adoption of the conference report.
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 37; Nays 2
AYES
Alexander Allen Bennett
Campbell Campsen Cash
Climer Corbin Cromer
Davis Fanning Gambrell
Goldfinch Gregory Grooms
Hembree Jackson Johnson
Leatherman Malloy Massey
Matthews, John McElveen Nicholson
Peeler Rankin Reese
Rice Sabb Scott
Senn Setzler Shealy
Timmons Turner Verdin
Young
Total--37
NAYS
Hutto Matthews, Margie
Total--2
H. 4375 -- Conference Report
The General Assembly, Columbia, S.C., June 27, 2018
The COMMITTEE OF CONFERENCE, to whom was referred:
H. 4375 (Word version) -- Reps. McCoy, Ott, Lucas, Anderson, Ballentine, Blackwell, Caskey, Crawford, Crosby, Davis, Finlay, Forrester, Gilliard, Hardee, Henegan, Hixon, Mack, Pope, Rutherford, J.E. Smith, Sandifer, Stavrinakis, Erickson, Huggins, W. Newton, Bales, Young, McEachern, Clary, Tallon, Brown, Fry, Robinson-Simpson, V.S. Moss, Clyburn, Martin, Magnuson, Bennett, Arrington, Daning, Weeks, Henderson and Govan: A BILL TO AMEND SECTION 58-33-220, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO DEFINITIONS UNDER THE BASE LOAD REVIEW ACT, SO AS TO ADD CERTAIN DEFINITIONS; TO REPEAL ARTICLES 4 AND 5, CHAPTER 33, TITLE 58, RELATING TO THE BASE LOAD REVIEW ACT, AND TO PROVIDE A SPECIFIC EXCEPTION TO THIS REPEAL; BY ADDING CHAPTER 34 TO TITLE 58 SO AS TO PROVIDE FOR THE MANNER IN WHICH AND PROCEDURES UNDER WHICH ELECTRICITY RATES FOR CERTAIN RATEPAYERS WHO ARE PAYING ADDITIONAL CHARGES UNDER THE BASE LOAD REVIEW ACT FOR THE CONSTRUCTION OF NUCLEAR PLANTS OR PROJECTS SHALL BE REVISED AND DETERMINED; AND TO PROVIDE FOR PROCEDURES AND PROVISIONS OF LAW WHICH APPLY AND DO NOT APPLY IN REGARD TO THE ADJUSTMENT OF ELECTRICITY RATES AS PROVIDED BY CHAPTER 34.
Beg leave to report that they have duly and carefully considered the same and recommend:
That the same do pass with the following amendments:
Amend the bill, as and if amended, by striking all after the enacting words and inserting:
/ SECTION 1. Section 58-33-220 of the 1976 Code is amended by adding appropriately numbered items to read:
"( ) 'Imprudent' or 'imprudence' includes, but is not limited to, lack of caution, care, or diligence as determined by the commission in regard to any action or decision taken by the utility or one acting on its behalf including, but not limited to, its officers, board, agents, employees, contractors, subcontractors, consultants affecting the project or any other person acting on behalf of or for the utility affecting the project. Imprudent or imprudence includes, but does not require, a finding of negligence, carelessness, or recklessness.
Imprudence on behalf of any contractor, subcontractor, agent, or person hired to construct a plant or perform any action or service on behalf of the utility shall be attributed to the utility.
( ) 'Prudent', 'prudence', or 'prudency' means a high standard of caution, care, and diligence in regard to any action or decision taken by the utility or one acting on its behalf including, but not limited to, its officers, board, agents, employees, contractors, subcontractors, consultants affecting the project or any other person acting on behalf of or for the utility affecting the project.
To the extent a utility enters a contract with a third party that delegates some or all decision-making authority related to the project, the utility retains the burden of establishing the prudency of specific items of cost or specific third-party decisions.
'Prudent', 'prudence', or 'prudency' also requires that any action or decision be made in a timely manner.
In determining whether any action or decision was prudent, the commission shall consider, including, but not limited to:
(a) whether the utility acts in a timely manner, with any passage of time which results in increased costs or expense prior to the utility acting or making the decision weighing against a finding of prudency;
(b) whether prior actions or decisions by the utility were imprudent and such imprudent actions led to a decision by the utility that could otherwise be prudent. Such circumstances weigh against a finding of prudency; and
(c) any other relevant factors, including commission of a fraudulent act, which are deemed not to be prudent.
As used in item (c), 'fraud' includes, in addition to its normal legal connotation, concealment, omission, misrepresentation, or nondisclosure of a material fact in any proceeding or filing before the commission or Office of Regulatory Staff. Proceedings and filings to which the provisions of this paragraph apply include, but are not limited to, rate or revised rate filings, responsive filings, motions, pleadings, briefs, memoranda, document requests, and other communications before the commission or Office of Regulatory Staff."
SECTION 2. A. As of the effective date of this act, the Public Service Commission must not accept a base load review application, nor may it consider any requests made pursuant to Article 4, Chapter 33 of Title 58 other than in a docket currently pending before the Commission.
B. The provisions of Article 4, Chapter 33 of Title 58 are repealed upon the conclusion of litigation concerning the abandonment of V.C. Summer Units 2 and 3.
SECTION 3. Title 58 of the 1976 Code is amended by adding:
"CHAPTER 34
Determination of Electricity Rates
Section 58-34-10. (A) The investor-owned utility holding the majority interest in the V. C. Summer Nuclear Reactor Units 2 and 3 at Jenkinsville, South Carolina, has entered into a merger agreement with an out-of-state investor-owned utility. This merger agreement contemplates the continuation of rate increases imposed under the Base Load Review Act contained in Article 4, Chapter 33, Title 58.
(B) Pursuant to the authority vested in the General Assembly by Section 1, Article IX of the Constitution of this State, the General Assembly is required to regulate investor owned utilities in order to protect the public interest. The General Assembly has determined that Section 1, Article IX of the Constitution requires that the General Assembly exercise its authority to set certain utility rates for the purpose of protecting the public interest until a determination can be made by the appropriate regulatory and judicial authorities. This rate shall apply to all customers of the investor-owned utility identified in subsection (A), which has imposed nine rate increases for the purpose of funding the V. C. Summer project.
Section 58-34-20. Within five calendar days after the effective date of this chapter, the Public Service Commission, by order, is directed to exercise its authority pursuant to Section 58-27-870(F) to provide an experimental rate that customers of the utility identified in Section 58-34-10 shall pay during the pendency of litigation currently before the commission which shall include full and final compliance by the utility with the order issued by Public Service Commission under this section or until replaced by an order of the commission under Section 58-34-30. This experimental rate shall cause rates to be reduced on a going forward basis in an amount equal to the electric utility rates these ratepayers are paying reduced by the following rate increases imposed under the provisions of the Base Load Review Act in the Public Service Commission's orders Docket No. 2011-207-E , Order No. 2011-738, Docket No. 2012-186-E , Order No. 2012-761, Docket No. 2013-150-E , Order No. 2013-680(A), Docket No. 2014-187-E , Order No. 2014-785, Docket No. 2015-160-E , Order No. 2015-712, Docket No. 2016-224-E, Order No. 2016-758, for the period of no earlier than April 1, 2018, until the issuance of the Public Service Commission's final order on the merits on the matters before the commission.
Section 58-34-30. Notwithstanding any other provision of law, the experimental rate set pursuant to Section 58-34-20 shall remain in full force and effect during the pendency of the matters before the commission. However, the commission shall monitor the net effect of the experimental rate and may alter the experimental rate, on its own motion, only if it determines that an adjustment to the experimental rate is necessary to satisfy constitutional requirements of utility ratemaking. If required to adjust the rate, the commission shall, under applicable provisions of law, determine the just and reasonable rates for these ratepayers after considering all factors and evidence. In determining such rate and in considering the constitutionally allowable zone of reasonableness in which rates may properly fall, the commission is directed to set the lowest possible rate within the zone of reasonableness. Nothing herein prevents the commission from adopting as its own rate the experimental rate directed by the General Assembly in Section 58-34-10 and ordered pursuant to Section 58-34-20.
Section 58-34-40. Any provision of Article 7, Chapter 27, Title 58 in conflict with the provisions of this chapter, including, but not limited to, Section 58-27-870(B), are suspended for purposes of the utility rates provided for by this chapter and for any pending matters related to V.C. Summer Nuclear Reactor Units 2 and 3 at Jenkinsville, South Carolina, pending before the commission on or after the effective date of this chapter. The suspension remains in effect during the pendency of any litigation or appeal concerning the experimental or interim rates directed by the General Assembly or ordered by the Public Service Commission pursuant to this chapter, or related issues surrounding the establishment of these rates, until a final determination of the matter, including any subsequent appeals, is made by the appropriate court.
Section 58-34-50. Section 58-27-930 and the time limitations contained in Section 58-33-240(A) and (E) are hereby suspended for purposes of the utility rates provided for by this chapter and for any pending matters related to V.C. Summer Nuclear Reactor Units 2 and 3 at Jenkinsville, South Carolina, pending before the commission on or after the effective date of this chapter. The suspension remains in effect during the pendency of any litigation or appeal concerning the experimental or interim rates directed by the General Assembly or ordered by the Public Service Commission pursuant to this chapter, or related issues surrounding the establishment of these rates, until a final determination of the matter, including any subsequent appeals, is made by the appropriate court."
SECTION 4. Section 58-33-280(G) of the 1976 Code is amended to read:
"(G) Where both Office of Regulatory Staff and the utility agree in writing on the revised rates to be implemented, the commission shall may give substantial weight to the agreement in issuing its revised rates order but may consider additional factors at its discretion."
SECTION 5. Section 37-6-602 of the 1976 Code of Laws is amended to read:
"Section 37-6-602. The Consumer Advocate may be the Administrator of Consumer Affairs or he may be appointed by the administrator with the approval of the Commission on Consumer Affairs. The Consumer Advocate must be an attorney qualified to practice in all courts of this State with a minimum of three eight years' practice experience."
SECTION 6. Section 37-6-604 of the 1976 Code of Laws is amended to read:
"Section 37-6-604. (A) The functions and duties of the Division of Consumer Advocacy are:
(1)to provide legal representation of the consumer interest before the state and federal regulatory agencies which undertake to fix rates or prices for consumer products or services or to enact regulations or establish policies related thereto and to provide legal representation of the consumer interest concerning insurance matters, certificates of need for health facilities and services as required for an activity under Section 44-7-160, and other health-related provisions;
(2) to monitor existing regulations, rate structures, and policies of that agency of special interest to consumers and report to the public through the news media proposed changes therein under consideration and the effect of those changes on the lives of the citizens of the State; and
(3) to evaluate and act upon requests from consumers concerning the matters set forth in items (1) and (2), except that any proceedings initiated by the Consumer Advocate must be brought on behalf of the public at large and not for individuals; initiation or continuation of any proceedings is in the sole discretion of the Consumer Advocate.
(B) The annual report required of the Commission on Consumer Affairs must include a report on the activities of the Division of Consumer Advocacy.
(C) After January 1, 2005, the division must not represent consumers in matters arising under Title 58. Matters or appeals under Title 58 that are pending on January 1, 2005, shall be transferred to the Office of Regulatory Staff. The Consumer Advocate shall be provided notice of any matter filed at the Public Service Commission that could impact consumers' utility rates, and may intervene as a party to advocate for the interest of consumers before the Public Service Commission and appellate courts in such matters as the Consumer Advocate deems necessary and appropriate."
SECTION 7. Section 37-6-607 of the 1976 Code of Laws is amended to read:
"Section 37-6-607. With the exception of matters arising under Title 58, the The Consumer Advocate is considered to have an interest sufficient to maintain actions for judicial review and may, as of right and in the manner prescribed by law, intervene or otherwise participate in any civil proceeding which involves the review or enforcement of an agency action that the Consumer Advocate determines may substantially affect the interests of consumers."
SECTION 8. Section 58-4-10 of the 1976 Code of Laws is amended to read:
"Section 58-4-10. (A) There is hereby created the Office of Regulatory Staff as a separate agency of the State with the duties and organizations as hereinafter provided.
(B) Unless and until it chooses not to participate, the Office of Regulatory Staff must be considered a party of record in all filings, applications, or proceedings before the commission. The regulatory staff must represent the public interest of South Carolina before the commission. For purposes of this chapter, 'public interest' means the a balancing of the following:
(1) concerns of the using and consuming public with respect to public utility services, regardless of the class of customer;
(2) economic development and job attraction and retention in South Carolina; and
(3) preservation of the financial integrity of the state's public utilities and continued investment in and maintenance of utility facilities so as to provide reliable and high quality utility services.
(C) The Office of Regulatory Staff is subject to the provision of Section 58-3-260 prohibiting ex parte communications with the commission, and any advice given to the commission by the regulatory staff must be given in a form, forum, and manner as may lawfully be given by any other party or person."
SECTION 9. Section 58-4-80 of the 1976 Code of Laws is amended to read:
"Section 58-4-80. The executive director representing the regulatory staff is considered to have an interest sufficient to maintain actions for judicial review from commission orders or decisions and may, as of right and in a manner prescribed by law, intervene or otherwise participate in any civil proceeding which involves the review or enforcement of commission action that the executive director determines may substantially affect the public interest. This right includes intervention in any action for judicial review from commission orders or decisions that are pending at any stage of the action. The executive director representing the regulatory staff has the same rights of appeal from commission orders or decisions as other parties to commission proceedings. On appeal, the Office of Regulatory Staff does not represent the commission."
SECTION 10. Section 58-4-55 of the 1976 Code is amended to read:
"Section 58-4-55. (A) The regulatory staff, in accomplishing its responsibilities under Section 58-4-50, may require the production of books, records, and other information to be produced at the regulatory staff's office, that, upon request of the regulatory staff, must be submitted under oath and without the requirement of a confidentiality agreement or protective order being first executed or sought. The regulatory staff must treat the information as confidential or proprietary unless or until the commission rules such information is not entitled to protection from public disclosure or the public utility agrees that such information is no longer confidential or proprietary. Unless the commission's order contains a finding to the contrary, all documents or information designated as confidential or proprietary pursuant to this subsection are exempt from public disclosure under Sections 30-4-10, et seq. and the regulatory staff shall not disclose such documents and information, or the contents thereof, to any member of the commission or to any other person or entity; provided, however, that, if the commission determines that it is necessary to view such documents or information, it shall order the regulatory staff to file the documents or information with the commission under seal, and such documents or information shall not be available for public inspection unless otherwise ordered by the commission.
If the books, records, or other information provided do not appear to disclose full and accurate information and, if such apparent deficiencies are not cured after reasonable notice, the regulatory staff may require the attendance and testimony under oath of the officers, accountants, or other agents of the parties having knowledge thereof at such place as the regulatory staff may designate and the expense of making the necessary examination or inspection for the procuring of the information must be paid by the party examined or inspected, to be collected by the regulatory staff by suit or action, if necessary. If, however, the examination and inspection and the reports thereof disclose that full and accurate information had previously been made, the expense of making the examination and inspection must be paid out of the funds of the regulatory staff.
(B) If the regulatory staff initiates an inspection, audit, or examination of a public utility, the public utility that is the subject of the inspection, audit, or examination may petition the commission to terminate or limit the scope of such inspection, audit, or examination. The commission must grant such petition if it finds that such inspection, audit, or examination is arbitrary, capricious, unnecessary, unduly burdensome, or unrelated to the public utility's regulated operations.
(1) If such an inspection, audit, or examination is not part of a contested case proceeding, the public utility may also raise objections or seek relief available under the South Carolina Rules of Civil Procedure to a party upon whom discovery is served or to a person upon whom a subpoena is served. The commission shall provide the regulatory staff reasonable notice to respond to any such objection or request. Absent the consent of the public utility raising such an objection or request and the Office of Regulatory Staff, the commission must rule on such an objection or request within sixty days of the date it was filed. During the pendency of the commission's ruling, the public utility making such an objection or request is not required to produce or provide access to any documents or information that is the subject of the objection or request.
(2) If such an inspection, audit, or examination is part of a contested case proceeding, the commission shall address objections to information sought by the regulatory staff in the same manner in which it addresses objections to discovery issued by the parties to the contested case proceeding.
(C) Any public utility that provides the regulatory staff with copies of or access to documents or information in the course of an inspection, audit, or examination that is not part of a contested case proceeding may designate any such documents or information as confidential or proprietary if it believes in good faith that such documents or information would be entitled to protection from public disclosure under the South Carolina Rules of Civil Procedure or any provision of South Carolina or federal law. The regulatory staff may petition the commission for an order that some or all of the documents so designated are not entitled to protection from public disclosure and it shall be incumbent on the utility to prove that such documents are entitled to protection from public disclosure under the South Carolina Rules of Civil Procedure or any provision of South Carolina or federal law. The commission shall rule on such petition after providing the regulatory staff and the utility an opportunity to be heard. Unless the commission's order on such a petition contains a finding to the contrary, all documents or information designated as confidential or proprietary pursuant to this subsection are exempt from public disclosure under Sections 30-4-10, et seq. and the regulatory staff shall not disclose such documents and information, or the contents thereof, to any member of the commission or to any other person or entity; provided, however, that, if the commission determines that it is necessary to view such documents or information in order to rule on such a petition, it shall order the regulatory staff to file the documents or information with the commission under seal, and such documents or information shall not be available for public inspection during the pendency of the petition.
(D) Nothing in this section restricts the regulatory staff's ability to serve discovery in a contested case proceeding that seeks the type of documents or information the regulatory staff has obtained in the course of any review, investigation, inspection, audit, or examination, nor does anything in this section restrict the ability of any public utility to object to such discovery or to seek relief regarding such discovery, including without limitation the entry of a protective order. The regulatory staff shall not be required to execute a confidentiality agreement or seek a protective order prior to accessing the public utility's documents or information, and such information or documents shall be treated as confidential or proprietary unless or until the commission rules such information is not entitled to protection from public disclosure or the public utility agrees that such information is no longer confidential or proprietary. Unless the commission's order contains a finding to the contrary, all documents or information designated as confidential or proprietary pursuant to this subsection are exempt from public disclosure under Sections 30-4-10, et seq. and the regulatory staff shall not disclose such documents and information, or the contents thereof, to any member of the commission or to any other person or entity; provided, however, that, if the commission determines that it is necessary to view such documents or information, it shall order the regulatory staff to file the documents or information with the commission under seal, and such documents or information shall not be available for public inspection unless otherwise ordered by the commission.
(E) The Office of Regulatory Staff, in order to accomplish any of the responsibilities assigned to it by Chapter 4, Title 58 or any other provision of law, may apply to the circuit court for subpoenas to be issued to entities over which the Public Service Commission does not have jurisdiction. Such subpoenas will be issued by the circuit court in the same manner as subpoenas are issued to parties to proceedings before that court, and all rules applicable to the issuance of such subpoenas, including enforcement and penalties, shall apply to subpoenas issued at the request of the regulatory staff."
SECTION 11. If any provision of this act is enjoined, held, or determined to be unconstitutional, invalid, or otherwise unenforceable by a court of competent jurisdiction, it is the intention of the General Assembly that the provision is severable from the remaining provisions of this act and that the injunction or holding does not invalidate or render unenforceable another provision of this act.
SECTION 12. This act takes effect upon approval by the Governor and applies to all cases, proceedings, petitions, or matters pending before the Public Service Commission or in any other court or venue on or after the effective date of this act. /
Amend title to conform.
/s/Sen. Nikki G. Setzler /s/Rep. J. Todd Rutherford
/s/Sen. Luke A. Rankin /s/Rep. Peter M. McCoy, Jr.
/s/Sen. A. Shane Massey /s/Rep. Kirkman Finlay III
On Part of the Senate. On Part of the House.
, and a message was sent to the House accordingly.
Message from the House
Columbia, S.C., June 27, 2018
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has adopted the Report of the Committee of Conference on:
H. 4375 (Word version) -- Reps. McCoy, Ott, Lucas, Anderson, Ballentine, Blackwell, Caskey, Crawford, Crosby, Davis, Finlay, Forrester, Gilliard, Hardee, Henegan, Hixon, Mack, Pope, Rutherford, J.E. Smith, Sandifer, Stavrinakis, Erickson, Huggins, W. Newton, Bales, Young, McEachern, Clary, Tallon, Brown, Fry, Robinson-Simpson, V.S. Moss, Clyburn, Martin, Magnuson, Bennett, Arrington, Daning, Weeks, Henderson and Govan: A BILL TO AMEND SECTION 58-33-220, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO DEFINITIONS UNDER THE BASE LOAD REVIEW ACT, SO AS TO ADD CERTAIN DEFINITIONS; TO REPEAL ARTICLES 4 AND 5, CHAPTER 33, TITLE 58, RELATING TO THE BASE LOAD REVIEW ACT, AND TO PROVIDE A SPECIFIC EXCEPTION TO THIS REPEAL; BY ADDING CHAPTER 34 TO TITLE 58 SO AS TO PROVIDE FOR THE MANNER IN WHICH AND PROCEDURES UNDER WHICH ELECTRICITY RATES FOR CERTAIN RATEPAYERS WHO ARE PAYING ADDITIONAL CHARGES UNDER THE BASE LOAD REVIEW ACT FOR THE CONSTRUCTION OF NUCLEAR PLANTS OR PROJECTS SHALL BE REVISED AND DETERMINED; AND TO PROVIDE FOR PROCEDURES AND PROVISIONS OF LAW WHICH APPLY AND DO NOT APPLY IN REGARD TO THE ADJUSTMENT OF ELECTRICITY RATES AS PROVIDED BY CHAPTER 34.
Very respectfully,
Speaker of the House
H. 4375--REPORT OF COMMITTEE OF CONFERENCE
ENROLLED FOR RATIFICATION
H. 4375 (Word version) -- Reps. McCoy, Ott, Lucas, Anderson, Ballentine, Blackwell, Caskey, Crawford, Crosby, Davis, Finlay, Forrester, Gilliard, Hardee, Henegan, Hixon, Mack, Pope, Rutherford, J.E. Smith, Sandifer, Stavrinakis, Erickson, Huggins, W. Newton, Bales, Young, McEachern, Clary, Tallon, Brown, Fry, Robinson-Simpson, V.S. Moss, Clyburn, Martin, Magnuson, Bennett, Arrington, Daning, Weeks, Henderson and Govan: A BILL TO AMEND SECTION 58-33-220, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO DEFINITIONS UNDER THE BASE LOAD REVIEW ACT, SO AS TO ADD CERTAIN DEFINITIONS; TO REPEAL ARTICLES 4 AND 5, CHAPTER 33, TITLE 58, RELATING TO THE BASE LOAD REVIEW ACT, AND TO PROVIDE A SPECIFIC EXCEPTION TO THIS REPEAL; BY ADDING CHAPTER 34 TO TITLE 58 SO AS TO PROVIDE FOR THE MANNER IN WHICH AND PROCEDURES UNDER WHICH ELECTRICITY RATES FOR CERTAIN RATEPAYERS WHO ARE PAYING ADDITIONAL CHARGES UNDER THE BASE LOAD REVIEW ACT FOR THE CONSTRUCTION OF NUCLEAR PLANTS OR PROJECTS SHALL BE REVISED AND DETERMINED; AND TO PROVIDE FOR PROCEDURES AND PROVISIONS OF LAW WHICH APPLY AND DO NOT APPLY IN REGARD TO THE ADJUSTMENT OF ELECTRICITY RATES AS PROVIDED BY CHAPTER 34.
The Report of the Committee of Conference having been adopted by both Houses, ordered that the title be changed to that of an Act, and the Act enrolled for Ratification.
A message was sent to the House accordingly.
H. 4009--REPORT OF THE
H. 4009 (Word version) -- Reps. Lucas, Williams, Crawford, Alexander, McCoy, Hiott, Clemmons, Bales, Bedingfield, Ott, G.R. Smith, Herbkersman, Sandifer and S. Rivers: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING CHAPTER 69 TO TITLE 12 SO AS TO ENACT THE "MOTORSPORTS ENTERTAINMENT COMPLEX INVESTMENT ACT" BY EXEMPTING CERTAIN BUILDING MATERIALS FOR A COMPLEX FROM THE SALES TAX AND TO PROVIDE THE PROCESS BY WHICH A QUALIFIED COMPANY MAY CLAIM THE EXEMPTION, TO CREATE THE MOTORSPORTS TOURISM INCENTIVE FUND TO AWARD GRANTS OR LOANS TO ATTRACT AND EXPAND TOURISM AND HOSPITALITY PROJECTS RELATED TO EVENTS AT SUCH COMPLEXES, TO PROVIDE THAT A COMPLEX IS ELIGIBLE FOR BENEFITS FROM THE CLOSING FUND, TO ALLOW A TAX CREDIT OF TWENTY-FIVE PERCENT OF THE COSTS INCURRED BY A TAXPAYER TO INSTALL EQUIPMENT OR TECHNOLOGY THAT ALLOWS INFORMATION TO BE TRANSMITTED THROUGH A WIRELESS LOCAL AREA NETWORK AT A COMPLEX; TO AMEND SECTION 12-20-110, RELATING TO THE APPLICABILITY OF CORPORATION LICENSE FEE PROVISIONS, SO AS TO MAKE SUCH PROVISIONS INAPPLICABLE TO A COMPLEX; AND TO AMEND SECTION 12-21-2425, RELATING TO THE ADMISSION LICENSE TAX, SO AS TO INCREASE THE EXEMPTION ON A COMPLEX, TO REMOVE THE TIME PERIOD FOR THE EXEMPTION, AND TO PROVIDE THAT THE EXEMPTED REVENUE MUST BE USED ON MARKETING FOR EVENTS AT THE COMPLEX.
On motion of Senator MALLOY, with unanimous consent, the Report of the Committee of Conference was taken up for immediate consideration.
Senator MALLOY spoke on the report.
The question then was adoption of the Report of Committee of Conference.
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 38; Nays 0
AYES
Alexander Allen Bennett
Campbell Campsen Cash
Climer Corbin Cromer
Davis Fanning Gambrell
Goldfinch Gregory Grooms
Hembree Hutto Jackson
Johnson Kimpson Leatherman
Malloy Matthews, Margie McElveen
Nicholson Peeler Rankin
Reese Rice Sabb
Scott Setzler Shealy
Talley Timmons Turner
Verdin Young
Total--38
NAYS
Total--0
The Committee of Conference Committee was adopted as follows:
H. 4009 -- Conference Report
The General Assembly, Columbia, S.C., May 23, 2018
The COMMITTEE OF CONFERENCE, to whom was referred:
H. 4009 (Word version) -- Reps. Lucas, Williams, Crawford, Alexander, McCoy, Hiott, Clemmons, Bales, Bedingfield, Ott, G.R. Smith, Herbkersman, Sandifer and S. Rivers: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING CHAPTER 69 TO TITLE 12 SO AS TO ENACT THE "MOTORSPORTS ENTERTAINMENT COMPLEX INVESTMENT ACT" BY EXEMPTING CERTAIN BUILDING MATERIALS FOR A COMPLEX FROM THE SALES TAX AND TO PROVIDE THE PROCESS BY WHICH A QUALIFIED COMPANY MAY CLAIM THE EXEMPTION, TO CREATE THE MOTORSPORTS TOURISM INCENTIVE FUND TO AWARD GRANTS OR LOANS TO ATTRACT AND EXPAND TOURISM AND HOSPITALITY PROJECTS RELATED TO EVENTS AT SUCH COMPLEXES, TO PROVIDE THAT A COMPLEX IS ELIGIBLE FOR BENEFITS FROM THE CLOSING FUND, TO ALLOW A TAX CREDIT OF TWENTY-FIVE PERCENT OF THE COSTS INCURRED BY A TAXPAYER TO INSTALL EQUIPMENT OR TECHNOLOGY THAT ALLOWS INFORMATION TO BE TRANSMITTED THROUGH A WIRELESS LOCAL AREA NETWORK AT A COMPLEX; TO AMEND SECTION 12-20-110, RELATING TO THE APPLICABILITY OF CORPORATION LICENSE FEE PROVISIONS, SO AS TO MAKE SUCH PROVISIONS INAPPLICABLE TO A COMPLEX; AND TO AMEND SECTION 12-21-2425, RELATING TO THE ADMISSION LICENSE TAX, SO AS TO INCREASE THE EXEMPTION ON A COMPLEX, TO REMOVE THE TIME PERIOD FOR THE EXEMPTION, AND TO PROVIDE THAT THE EXEMPTED REVENUE MUST BE USED ON MARKETING FOR EVENTS AT THE COMPLEX.
Beg leave to report that they have duly and carefully considered the same and recommend:
That the same do pass with the following amendments: (Reference is to Printer's Version 5/8/18--S.)
Amend the bill, as and if amended, by striking after the title and before the enacting clause and inserting:
/ Whereas, since 1950, with the inaugural running of the Southern 500, the first stock car race on a paved track, South Carolina has served as a cornerstone in the development of stock car racing, one of the fastest growing and most popular spectator sports in the country; and
Whereas, South Carolina lays claim to many of the legends of NASCAR racing, including Rex White, David Pearson, Bud Moore, James Hylton, Tiny Lund, and Cale Yarborough; and
Whereas, the State of South Carolina is rich in historical references to the sport of stock car racing, as evidenced by the Darlington Raceway Stock Car Museum and the National Motorsports Press Association Hall of Fame, in addition to dirt raceways across the State of South Carolina that served as home to the fledgling sport of NASCAR racing in the 1950s; and
Whereas, the NASCAR events in South Carolina focus our nation's attention and the attention of the world upon our great State as a sport and tourism destination each year; and
Whereas, the annual economic impact that NASCAR racing has on South Carolina is in excess of fifty million dollars, as NASCAR fans from across the country and around the world visit the State each year to attend racing events and then vacation in communities throughout the Palmetto State. Now, therefore, /
Amend further by striking all after the enacting words and inserting:
/ SECTION 1. Title 12 of the 1976 Code is amended by adding:
"CHAPTER 69
Motorsports Entertainment Complex Investment
Section 12-69-10. This chapter may be cited as the 'Motorsports Entertainment Complex Investment Act'.
Section 12-69-20. For purposes of this chapter:
(1) 'Company' means any corporation, partnership, limited liability company, or other business entity.
(2) 'Department' means the Department of Revenue.
(3) 'Motorsports entertainment complex' has the same meaning as provided in Section 12-21-2425.
Section 12-69-30. (A) A company, upon making application for, meeting the requirements of, and receiving written certification of that designation from the department, as provided in subsection (B), is exempt from state and local sales tax on building materials, supplies, fixtures, and equipment for the construction, repair, or improvement of or that become a part of a motorsports entertainment complex.
(B) A company shall become a qualified company by applying with the department. The director of the department shall approve the application so long as the application is accompanied by a practical plan to make a capital investment of at least ten million dollars on any motorsport entertainment complex in this State within the five-year period immediately following the approval of the application. Upon receiving written certification from the department, a company may utilize the exemption specified in subsection (A).
(C) Once a company has met the requirements of subsection (B), the department shall issue a sales and use tax exemption certificate to the company as evidence of the exemption. The exemption is effective upon receipt and shall remain effective until December thirty-first of the fifth full calendar year after its issuance. Once the exemption certificate is ineffective, the company must return the exemption certificate to the department and submit a report to the department of the actual expenditures made in South Carolina in connection with the investment. The company must designate a member or representative of the company to work with the department on reporting of the investment.
(D) A company that is approved and receives a sales and use tax exemption certificate but fails to meet the capital investment requirements within the five-year period, is liable for the sales and use taxes that would have been paid had the approval not been granted in the same proportion as the actual capital investment failed to meet the required capital investment. The company must be given a sixty-day period in which to pay the sales and use taxes without incurring penalties. The sales and use taxes are considered due as of the date the tangible personal property was purchased in or brought into South Carolina for use, storage, or consumption."
SECTION 2. Except where specified otherwise, this act takes effect upon approval by the Governor and applies to tax years beginning after 2017. /
/ TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING CHAPTER 69 TO TITLE 12 SO AS TO ENACT THE "MOTORSPORTS ENTERTAINMENT COMPLEX INVESTMENT ACT" BY EXEMPTING CERTAIN BUILDING MATERIALS FOR A COMPLEX FROM THE SALES TAX AND TO PROVIDE THE PROCESS BY WHICH A QUALIFIED COMPANY MAY CLAIM THE EXEMPTION. /
/s/Sen. Gerald Malloy /s/Rep. James H. "Jay" Lucas
/s/Sen. Paul G. Campbell, Jr. /s/Rep. J. Gary Simrill
/s/Sen. Shane R. Martin /s/Rep. Robert Q. Williams
On Part of the Senate. On Part of the House.
, and a message was sent to the House accordingly.
Message from the House
Columbia, S.C., June 27, 2018
Mr. President and Senators:
The House respectfully informs your Honorable Body that the Report of the Committee of Conference having been adopted by both Houses, and this Bill having been read three times in each House, it was ordered that the title thereof be changed to that of an Act and that it be enrolled for Ratification:
H. 4009 (Word version) -- Reps. Lucas, Williams, Crawford, Alexander, McCoy, Hiott, Clemmons, Bales, Bedingfield, Ott, G.R. Smith, Herbkersman, Sandifer and S. Rivers: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING CHAPTER 69 TO TITLE 12 SO AS TO ENACT THE "MOTORSPORTS ENTERTAINMENT COMPLEX INVESTMENT ACT" BY EXEMPTING CERTAIN BUILDING MATERIALS FOR A COMPLEX FROM THE SALES TAX AND TO PROVIDE THE PROCESS BY WHICH A QUALIFIED COMPANY MAY CLAIM THE EXEMPTION, TO CREATE THE MOTORSPORTS TOURISM INCENTIVE FUND TO AWARD GRANTS OR LOANS TO ATTRACT AND EXPAND TOURISM AND HOSPITALITY PROJECTS RELATED TO EVENTS AT SUCH COMPLEXES, TO PROVIDE THAT A COMPLEX IS ELIGIBLE FOR BENEFITS FROM THE CLOSING FUND, TO ALLOW A TAX CREDIT OF TWENTY-FIVE PERCENT OF THE COSTS INCURRED BY A TAXPAYER TO INSTALL EQUIPMENT OR TECHNOLOGY THAT ALLOWS INFORMATION TO BE TRANSMITTED THROUGH A WIRELESS LOCAL AREA NETWORK AT A COMPLEX; TO AMEND SECTION 12-20-110, RELATING TO THE APPLICABILITY OF CORPORATION LICENSE FEE PROVISIONS, SO AS TO MAKE SUCH PROVISIONS INAPPLICABLE TO A COMPLEX; AND TO AMEND SECTION 12-21-2425, RELATING TO THE ADMISSION LICENSE TAX, SO AS TO INCREASE THE EXEMPTION ON A COMPLEX, TO REMOVE THE TIME PERIOD FOR THE EXEMPTION, AND TO PROVIDE THAT THE EXEMPTED REVENUE MUST BE USED ON MARKETING FOR EVENTS AT THE COMPLEX.
Very respectfully,
Speaker of the House
H. 3789--REPORT OF THE
H. 3789 (Word version) -- Reps. Govan, Yow, Henegan, J.E. Smith, Thigpen, Hart, Clemmons, Whipper and Brown: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, SO AS TO ENACT THE "SOUTH CAROLINA YOUTH CHALLENGE ACADEMY AND SOUTH CAROLINA JOBS CHALLENGE PROGRAM EXPUNGEMENT ACT"; BY ADDING ARTICLE 10 TO CHAPTER 22, TITLE 17 SO AS TO PROVIDE THAT PERSONS ELIGIBLE FOR EXPUNGEMENT OF A CRIMINAL RECORD PURSUANT TO SECTION 17-22-910 WHO SUCCESSFULLY GRADUATE AND COMPLETE THE SOUTH CAROLINA YOUTH CHALLENGE ACADEMY AND SOUTH CAROLINA JOBS CHALLENGE PROGRAM ADMINISTERED BY THE SOUTH CAROLINA ARMY NATIONAL GUARD MAY APPLY TO HAVE THEIR RECORD EXPUNGED UPON SUCCESSFUL GRADUATION AND COMPLETION OF THE PROGRAMS UNDER CERTAIN DELINEATED CIRCUMSTANCES; AND TO AMEND SECTION 17-22-940, AS AMENDED, RELATING TO THE EXPUNGEMENT PROCESS, SO AS TO INCLUDE A REFERENCE TO THE DIRECTOR OF THE SOUTH CAROLINA YOUTH CHALLENGE ACADEMY ATTESTING TO THE ELIGIBILITY OF THE CHARGE FOR EXPUNGEMENT ON AN EXPUNGEMENT APPLICATION.
On motion of Senator CAMPSEN, with unanimous consent, the Report of the Committee of Conference was taken up for immediate consideration.
Senator CAMPSEN spoke on the report.
The question then was adoption of the Report of Committee of Conference.
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 39; Nays 1
AYES
Alexander Allen Bennett
Campbell Campsen Cash
Climer Cromer Fanning
Gambrell Goldfinch Gregory
Grooms Hembree Hutto
Jackson Johnson Kimpson
Leatherman Malloy Massey
Matthews, John Matthews, Margie McElveen
Nicholson Peeler Rankin
Reese Rice Sabb
Scott Senn Setzler
Shealy Talley Timmons
Turner Verdin Young
Total--39
NAYS
Corbin
Total--1
The Committee of Conference Committee was adopted as follows:
H. 3789 -- Conference Report
The General Assembly, Columbia, S.C., June 27, 2018
The COMMITTEE OF CONFERENCE, to whom was referred:
H. 3789 (Word version) -- Reps. Govan, Yow, Henegan, J.E. Smith, Thigpen, Hart, Clemmons, Whipper and Brown: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, SO AS TO ENACT THE "SOUTH CAROLINA YOUTH CHALLENGE ACADEMY AND SOUTH CAROLINA JOBS CHALLENGE PROGRAM EXPUNGEMENT ACT"; BY ADDING ARTICLE 10 TO CHAPTER 22, TITLE 17 SO AS TO PROVIDE THAT PERSONS ELIGIBLE FOR EXPUNGEMENT OF A CRIMINAL RECORD PURSUANT TO SECTION 17-22-910 WHO SUCCESSFULLY GRADUATE AND COMPLETE THE SOUTH CAROLINA YOUTH CHALLENGE ACADEMY AND SOUTH CAROLINA JOBS CHALLENGE PROGRAM ADMINISTERED BY THE SOUTH CAROLINA ARMY NATIONAL GUARD MAY APPLY TO HAVE THEIR RECORD EXPUNGED UPON SUCCESSFUL GRADUATION AND COMPLETION OF THE PROGRAMS UNDER CERTAIN DELINEATED CIRCUMSTANCES; AND TO AMEND SECTION 17-22-940, AS AMENDED, RELATING TO THE EXPUNGEMENT PROCESS, SO AS TO INCLUDE A REFERENCE TO THE DIRECTOR OF THE SOUTH CAROLINA YOUTH CHALLENGE ACADEMY ATTESTING TO THE ELIGIBILITY OF THE CHARGE FOR EXPUNGEMENT ON AN EXPUNGEMENT APPLICATION.
Beg leave to report that they have duly and carefully considered the same and recommend:
That the same do pass with the following amendments: (Reference is to Printer's Version 5/10/17-H.)
Amend the bill, as and if amended, by striking all after the title and inserting:
/ Whereas, the South Carolina General Assembly recognizes the efforts of the South Carolina National Guard in administering the South Carolina Youth Challenge Academy program designed to help at-risk youth learn basic skills and achieve the education necessary to succeed in life; and
Whereas, offering two classes a year, the program provides a unique educational environment and serves the state's youth looking for a second chance to succeed; and
Whereas, the program is led by current and retired members of the South Carolina Army National Guard and other branches of the military providing military leadership and discipline to students in the program with the eight core components of the intensive residential program being academic excellence, life-coping skills, job skills, health and hygiene, responsible citizenship, service to community, leadership/followership, and physical fitness; and
Whereas, in partnership with the federal Department of Labor, the State is pleased to offer youth who successfully graduate from the program an opportunity to take part in a five and one-half month South Carolina Jobs Challenge Program which provides training for careers in such fields as nursing assistance, welding, and computer technology; and
Whereas, this approximate yearlong commitment by youths ages sixteen to nineteen towards building a better future warrants allowing those youths that may have a criminal record otherwise eligible for expungement to apply to have their record expunged upon the successful graduation and completion of the South Carolina Youth Challenge Academy and the South Carolina Jobs Challenge Program administered by the South Carolina Army National Guard. Now, therefore,
Be it enacted by the General Assembly of the State of South Carolina:
SECTION 1. This act may be cited as the "South Carolina Youth Challenge Academy and South Carolina Jobs Challenge Program Expungement Act".
SECTION 2. Chapter 22, Title 17 of the 1976 Code is amended by adding:
"Article 10
South Carolina Youth Challenge Academy and South Carolina Jobs Challenge Program Expungement
Section 17-22-1010. (A) A person who is eligible for expungement of his criminal record pursuant to the provisions of Sections 22-5-910, 22-5-920, 34-11-90(e), and 56-5-750(F) may apply to have his record expunged pursuant to the procedures provided in Article 9 if he graduates and successfully completes the South Carolina Youth Challenge Academy and the South Carolina Jobs Challenge Program administered by the South Carolina Army National Guard. Notwithstanding another provision of law, such person may apply for expungement immediately upon graduation and successful completion of the South Carolina Youth Challenge Academy and the South Carolina Jobs Challenge Program.
(B) If the person has had no other conviction during the approximately one-year period as provided in subsection (A), the circuit court may issue an order expunging the records including any associated bench warrant. No person may have his records expunged under this section more than once.
(C) If the expungement order is granted by the court, the records must be destroyed or retained by any law enforcement agency or municipal, county, or state agency or department pursuant to the provisions of Section 17-1-40.
(D) The effect of the expungement order is to restore the person, in the contemplation of the law, to the status he occupied before the arrest or indictment or information. No person as to whom the order has been entered may be held pursuant to another provision of law to be guilty of perjury or otherwise giving a false statement by reason of his failure to recite or acknowledge the arrest, or indictment or information, or trial in response to an inquiry made of him for any purpose.
(E) After the expungement, the South Carolina Law Enforcement Division is required to keep a nonpublic record of the offense and the date of the expungement to ensure that no person takes advantage of the rights of this section more than once. This nonpublic record is not subject to release pursuant to Section 34-11-95, the Freedom of Information Act, or any other provision of law except to those authorized law or court officials who need to know this information in order to prevent the rights afforded by this section from being taken advantage of more than once.
(F) As used in this section, 'conviction' includes a guilty plea, a plea of nolo contendere, or the forfeiting of bail."
SECTION 3. Section 17-22-910 of the 1976 Code, as last amended by Act 22 of 2015, is further amended to read:
"Section 17-22-910. (A) Applications for expungement of all criminal records must be administered by the solicitor's office in each circuit in the State as authorized pursuant to:
(1) Section 34-11-90(e), first offense misdemeanor fraudulent check;
(2) Section 44-53-450(b), conditional discharge;
(3) Section 22-5-910, first offense conviction in magistrates court;
(4) Section 22-5-920, youthful offender act;
(5) Section 56-5-750(F), first offense failure to stop when signaled by a law enforcement vehicle;
(6) Section 17-22-150(a), pretrial intervention;
(7) Section 17-1-40, criminal records destruction, except as provided in Section 17-22-950;
(8) Section 63-19-2050, juvenile expungements;
(9) Section 17-22-530(A), alcohol education program;
(10) Section 17-22-330(A), traffic education program; and
(11) Section 17-22-1010, youth challenge academy and jobs challenge program; and
(11)(12) any other statutory authorization.
(B) A person's eligibility for expungement of an offense contained in this section, or authorized by any other provision of law, must be based on the offense that the person pled guilty to or was convicted of committing and not on an offense for which the person may have been charged. In addition, if an offense for which a person was convicted is subsequently repealed and the elements of the offense are consistent with an existing similar offense which is currently eligible for expungement, a person's eligibility for expungement of an offense must be based on the existing similar offense.
(C) The provisions of this section apply retroactively to allow expungement as provided by law for each offense delineated in subsection (A) by persons convicted prior to the enactment of this section or the addition of a specific item contained in subsection (A)."
SECTION 4. Section 17-22-940(E) of the 1976 Code, as last amended by Act 276 of 2014, is further amended to read:
"(E) In cases when charges are sought to be expunged pursuant to Section 17-22-150(a), 17-22-530(a), 22-5-910, or 44-53-450(b), or 17-22-1010, the circuit pretrial intervention director, alcohol education program director, traffic education program director, South Carolina Youth Challenge Academy director, or summary court judge shall attest by signature on the application to the eligibility of the charge for expungement before either the solicitor or his designee and then the circuit court judge, or the family court judge in the case of a juvenile, signs the application for expungement."
SECTION 5. This act takes effect upon approval by the Governor. /
Amend title to conform.
/s/Sen. George E. Campsen, III /s/Rep. Thomas E. Pope
/s/Senator John L. Scott /s/Rep. J. David Weeks
/s/Senator Tom Young, Jr. /s/Rep. Chris Murphy
On Part of the Senate. On Part of the House.
, and a message was sent to the House accordingly.
THE SENATE PROCEEDED TO A CONSIDERATION OF THE VETOES.
Message from the House
Columbia, S.C., June 27, 2018
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has sustained the veto by the Governor on R.272, H. 4973 by a vote of 60 to 46:
Very respectfully,
Speaker of the House
Message from the House
Columbia, S.C., June 27, 2018
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has overridden the veto by the Governor on R.237, H. 3209 by a vote of 108 to 1:
(R237, H3209 (Word version)) -- Reps. Pope, Robinson-Simpson, Crosby, Whipper, Brown, M. Rivers, King, Magnuson, Norrell, Martin, B. Newton, Long, Govan, Henegan, Dillard and Gilliard: AN ACT TO AMEND SECTION 17-22-910, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO APPLICATIONS FOR THE EXPUNGEMENT OF CRIMINAL RECORDS FOR CERTAIN OFFENSES, SO AS TO ADD FIRST OFFENSE SIMPLE POSSESSION OR POSSESSION WITH INTENT TO DISTRIBUTE DRUGS TO THE LIST OF OFFENSES ELIGIBLE FOR EXPUNGEMENT, AND TO PROVIDE FOR ELIGIBILITY FOR EXPUNGEMENT OF OFFENSES SUBSEQUENTLY REPEALED WHEN THE ELEMENTS OF THE OFFENSE ARE CONSISTENT WITH AN EXISTING SIMILAR OFFENSE WHICH IS SUBJECT TO EXPUNGEMENT AND TO CLARIFY THAT EXPUNGEMENT PROVISIONS APPLY RETROACTIVELY TO THE OFFENSES DELINEATED; TO AMEND SECTION 22-5-910, RELATING TO SUMMARY COURT OFFENSES ELIGIBLE FOR EXPUNGEMENT, SO AS TO EXPAND ELIGIBILITY BEYOND FIRST OFFENSES AND CLARIFY THAT EXPUNGEMENT PROVISIONS APPLY RETROACTIVELY; TO AMEND SECTION 22-5-920, RELATING TO EXPUNGEMENT OF PERSONS CONVICTED AS YOUTHFUL OFFENDERS, SO AS TO REDEFINE "CONVICTION" TO EXPAND ELIGIBILITY, TO INCLUDE THAT A PERSON REQUIRED TO REGISTER ON THE SEX OFFENDER REGISTRY IS NOT ELIGIBLE FOR EXPUNGEMENT, AND PROVIDE RETROACTIVE APPLICATION UNDER CERTAIN CIRCUMSTANCES; BY ADDING SECTION 22-5-930 SO AS TO PROVIDE FOR EXPUNGEMENT ELIGIBILITY FOR FIRST OFFENSE CONVICTIONS OF CERTAIN CONTROLLED SUBSTANCE OFFENSES; TO AMEND SECTION 63-19-2050, RELATING TO DESTRUCTION OF RECORDS OF PERSONS ADJUDICATED DELINQUENT, SO AS TO ALLOW FOR EXPUNGEMENT OF ANY NUMBER OF OFFENSES FROM A SINGLE SENTENCING PROCEEDING FOR CLOSELY CONNECTED OFFENSES; TO AMEND SECTION 17-22-940, RELATING TO FEES ASSOCIATED WITH THE EXPUNGEMENT PROCESS, SO AS TO RESTRUCTURE THE FEES PROCESS AND ALLOW FOR THE COLLECTION OF PRIVATE DONATIONS, AND TO MAKE CONFORMING CHANGES; AND BY ADDING SECTION 17-22-960 SO AS TO PROVIDE IMMUNITY FOR EMPLOYERS WHO HIRE PERSONS WHOSE CRIMINAL RECORDS HAVE BEEN EXPUNGED.
Very respectfully,
Speaker of the House
VETO OVERRIDDEN
(R237, H3209 (Word version)) -- Reps. Pope, Robinson-Simpson, Crosby, Whipper, Brown, M. Rivers, King, Magnuson, Norrell, Martin, B. Newton, Long, Govan, Henegan, Dillard and Gilliard: AN ACT TO AMEND SECTION 17-22-910, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO APPLICATIONS FOR THE EXPUNGEMENT OF CRIMINAL RECORDS FOR CERTAIN OFFENSES, SO AS TO ADD FIRST OFFENSE SIMPLE POSSESSION OR POSSESSION WITH INTENT TO DISTRIBUTE DRUGS TO THE LIST OF OFFENSES ELIGIBLE FOR EXPUNGEMENT, AND TO PROVIDE FOR ELIGIBILITY FOR EXPUNGEMENT OF OFFENSES SUBSEQUENTLY REPEALED WHEN THE ELEMENTS OF THE OFFENSE ARE CONSISTENT WITH AN EXISTING SIMILAR OFFENSE WHICH IS SUBJECT TO EXPUNGEMENT AND TO CLARIFY THAT EXPUNGEMENT PROVISIONS APPLY RETROACTIVELY TO THE OFFENSES DELINEATED; TO AMEND SECTION 22-5-910, RELATING TO SUMMARY COURT OFFENSES ELIGIBLE FOR EXPUNGEMENT, SO AS TO EXPAND ELIGIBILITY BEYOND FIRST OFFENSES AND CLARIFY THAT EXPUNGEMENT PROVISIONS APPLY RETROACTIVELY; TO AMEND SECTION 22-5-920, RELATING TO EXPUNGEMENT OF PERSONS CONVICTED AS YOUTHFUL OFFENDERS, SO AS TO REDEFINE "CONVICTION" TO EXPAND ELIGIBILITY, TO INCLUDE THAT A PERSON REQUIRED TO REGISTER ON THE SEX OFFENDER REGISTRY IS NOT ELIGIBLE FOR EXPUNGEMENT, AND PROVIDE RETROACTIVE APPLICATION UNDER CERTAIN CIRCUMSTANCES; BY ADDING SECTION 22-5-930 SO AS TO PROVIDE FOR EXPUNGEMENT ELIGIBILITY FOR FIRST OFFENSE CONVICTIONS OF CERTAIN CONTROLLED SUBSTANCE OFFENSES; TO AMEND SECTION 63-19-2050, RELATING TO DESTRUCTION OF RECORDS OF PERSONS ADJUDICATED DELINQUENT, SO AS TO ALLOW FOR EXPUNGEMENT OF ANY NUMBER OF OFFENSES FROM A SINGLE SENTENCING PROCEEDING FOR CLOSELY CONNECTED OFFENSES; TO AMEND SECTION 17-22-940, RELATING TO FEES ASSOCIATED WITH THE EXPUNGEMENT PROCESS, SO AS TO RESTRUCTURE THE FEES PROCESS AND ALLOW FOR THE COLLECTION OF PRIVATE DONATIONS, AND TO MAKE CONFORMING CHANGES; AND BY ADDING SECTION 17-22-960 SO AS TO PROVIDE IMMUNITY FOR EMPLOYERS WHO HIRE PERSONS WHOSE CRIMINAL RECORDS HAVE BEEN EXPUNGED.
The veto of the Governor was taken up for immediate consideration.
Senator HEMBREE argued in favor of overriding the veto.
Senator HEMBREE moved that the veto of the Governor be overridden.
The question was put, "Shall the Act become law, the veto of the Governor to the contrary notwithstanding?"
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 35; Nays 5
AYES
Alexander Allen Bennett
Campbell Campsen Cash
Climer Cromer Fanning
Gambrell Goldfinch Gregory
Grooms Hembree Hutto
Jackson Johnson Kimpson
Leatherman Malloy Massey
Matthews, John Matthews, Margie McElveen
Nicholson Rankin Reese
Sabb Scott Setzler
Shealy Talley Timmons
Turner Young
Total--35
NAYS
Corbin Peeler Rice
Senn Verdin
Total--5
The necessary two-thirds vote having been received, the veto of the Governor was overridden, and a message was sent to the House accordingly.
H. 4950--GENERAL APPROPRIATIONS BILL
Senator LEATHERMAN was recognized to give a status report on the Committee of Conference.
On motion of Senator LEATHERMAN, the Senate agreed that if and when the Senate adjourns today, it stand adjourned to meet tomorrow at 10:00 A.M.
LOCAL APPOINTMENTS
Confirmations
Having received a favorable report from the Senate, the following appointments were confirmed in open session:
Reappointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Martin Ira Easler, 209 Short Street, Kingstree, SC 29556-3926
Reappointment, Abbeville County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Susan G. Gladden, 438 Highway 20, Abbeville, SC 29620-4130
Initial Appointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Randy Brice Foxworth, 209 Short Street, Kingstree, SC 29510-3926
Reappointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
William Driggers, 209 Short Street, Kingstree, SC 29556-3926
Reappointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Brian McKnight, 209 Short Street, Kingstree, SC 29556-3926
Reappointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Bryan Keith Griffin, 115 North Harvin Street, Sumter, SC 29150-4956
Reappointment, Sumter County Magistrate, with the term to commence April 30, 2019, and to expire April 30, 2022
Fred H. Gordon, 115 North Harvin Street, Sumter, SC 29150-4956
Reappointment, Abbeville County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Philip D. Ray, 527 Noble Dr., Abbeville, SC 29620-4115
Reappointment, Abbeville County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Carolyn Brownlee, 417 Hanover Rd., Abbeville, SC 29620-5234
Reappointment, Williamsburg County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Glen Kennedy, 209 Short Street, Kingstree, SC 29556-3926
Reappointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Cecil Jackson, 115 North Harvin Street, Sumter, SC 29150-4956
Reappointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Larry Blanding, 190 East Canal Street, Sumter, SC 29150-4951
Initial Appointment, Marlboro County Part-Time Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Grover McQueen, 502 McQueen Rd., Bennettsville, SC 29512-7923
Initial Appointment, Spartanburg County Part-Time Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Chuck Bagwell, 318 Woodgrove Trace, Spartanburg, SC 29301-6432
Initial Appointment, Georgetown County Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Johnathan Guiles, 32 Genesis Dr., Georgetown, SC 29440-9398 VICE Elaine C. Elliot
Reappointment, Abbeville County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Initial Appointment, Hampton County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Tonja Alexander, P.O. Box 837, Varnville, SC 29944-0837
Initial Appointment, Marlboro County Part-Time Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Delton Powers, 107 S. Parsonage Street, Bennettsville, SC 29572 VICE Gail McInnis
Initial Appointment, Richland County Part-Time Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Roger Myers, 430 Old Bluff Road, Hopkins, SC 29061-9112 VICE New Seat
Initial Appointment, York County Part-Time Magistrate, with the term to commence April 30, 2015, and to expire April 30, 2019
Brooke Rhodes, 12088 Smithford Road, Hickory Grove, SC 29717-7765 VICE Melvin Howell
Initial Appointment, Sumter County Magistrate, with the term to commence April 30, 2018, and to expire April 30, 2022
Lee Anna Tindal, 190 East Canal Street, Sumter, SC 29150-4951
On motion of Senator LEATHERMAN, the Senate agreed to stand adjourned.
On motion of Senator ALEXANDER, with unanimous consent, the Senate stood adjourned out of respect to the memory of Mr. John "Johnny" Walter Fields of Seneca, S.C. Johnny served in the United States Army and received a Purple Heart for valor in the field. He later earned a Juris Doctor degree from the University of South Carolina. He served as the Seneca City Judge and as Assistant Solicitor before becoming a member of City Council. He served on the board of trustees for the University of South Carolina. Johnny was a member of Bethel Presbyterian Church. Johnny was a loving husband, devoted father and doting grandfather who will be dearly missed.
and
| 2018-07-18T23:50:42 |
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|
https://pdglive.lbl.gov/Particle.action?init=0&node=M249&home=MXXX035
|
CHARMED MESONS($\mathit C$ = $\pm1$) ${{\mathit D}^{+}}$ = ${\mathit {\mathit c}}$ ${\mathit {\overline{\mathit d}}}$, ${{\mathit D}^{0}}$ = ${\mathit {\mathit c}}$ ${\mathit {\overline{\mathit u}}}$, ${{\overline{\mathit D}}^{0}}$ = ${\mathit {\overline{\mathit c}}}$ ${\mathit {\mathit u}}$, ${{\mathit D}^{-}}$ = ${\mathit {\overline{\mathit c}}}$ ${\mathit {\mathit d}}$, similarly for ${{\mathit D}^{*}}$ 's
#### ${{\mathit D}_{{1}}^{*}{(2760)}^{0}}$
$I(J^P)$ = $1/2(1^{-})$
$\mathit J{}^{P}$ determined by AAIJ 2015V from the Dalitz plot analysis of ${{\mathit B}^{-}}$ $\rightarrow$ ${{\mathit D}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{-}}$ decays.
${{\mathit D}_{{1}}^{*}{(2760)}^{0}}$ MASS $2781 \pm22$ MeV
${{\mathit D}_{{1}}^{*}{(2760)}^{0}}$ WIDTH $177 \pm40$ MeV
$\Gamma_{1}$ ${{\mathit D}^{+}}{{\mathit \pi}^{-}}$ seen 637
FOOTNOTES
| 2022-12-07T19:59:21 |
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|
https://www.legisquebec.gouv.qc.ca/en/version/cr/A-29.01,%20r.%204%20?code=se:6_2_1&history=20221128
|
### A-29.01, r. 4 - Regulation respecting the basic prescription drug insurance plan
6.2.1. Notwithstanding the provisions of section 6.2, the rates of adjustment of the maximum contribution and deductible may not exceed the rate of increase in the Pension index established under the Act respecting the Québec Pension Plan (chapter R-9) applicable on January 1 of the year where the adjustment takes place, which rate is:
(1) for the maximum contribution:
(a) reduced by 0.5% in regard to the persons referred to in the first paragraph of section 28 of the Act respecting prescription drug insurance (chapter A-29.01);
(b) increased by 0.5%, in regard to the persons referred to in the second paragraph of section 28 of the Act respecting prescription drug insurance;
(2) for the deductible, increased by 0.5%.
The rate of adjustment of the deductible may however be less than that established in accordance with the provisions of the first paragraph of this section and the first paragraph of section 6.2, where the amount of the deductible is equivalent to more than 20% of the amount of the maximum contribution in the case of the persons referred to in the second paragraph of section 28 of the Act respecting prescription drug insurance.
O.C. 1300-2020, s. 1.
| 2023-02-09T05:42:43 |
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|
https://pos.sissa.it/382/232/
|
Volume 382 - The Eighth Annual Conference on Large Hadron Collider Physics (LHCP2020) - Poster session
Collider probes of real triplet scalar dark matter
Y. Du
Full text: pdf
Pre-published on: October 16, 2020
Published on:
Abstract
We study the real triplet model in which the neutral component of the triplet is a dark matter candidate and the charge components are long-lived. The long-lived triplet particles will result in disappearing charged tracks when produced at colliders. Utilizing this disappearing charged track signature from the decay of the charged components, we study exclusion limits from the LHC and a prospective 100TeV $pp$ collider. We also investigate the dark matter candidate and obtain constraints from present and future dark matter direct detection experiments. We conclude that XENON20T could cover almost the entire parameter space of this model except for a vanishingly small portal coupling.
How to cite
Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.
Open Access
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
| 2020-10-24T09:38:20 |
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https://huggingface.co/datasets/olivierdehaene/xkcd
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# Datasets: olivierdehaene /xkcd
Languages: English
Multilinguality: monolingual
Size Categories: 1K<n<10K
Language Creators: other
Dataset Preview
id (int64)title (string)image_title (string)url (string)image_url (string)explained_url (string)transcript (string)explanation (string)
1
"Barrel - Part 1"
"Barrel - Part 1"
"https://www.xkcd.com/1"
"https://imgs.xkcd.com/comics/barrel_cropped_(1).jpg"
"https://www.explainxkcd.com/wiki/index.php/1:_Barrel_-_Part_1"
"[A boy sits in a barrel which is floating in an ocean.] Boy: i wonder where i'll float next? [A smaller frame with a zoom out of the boy in the barrel seen from afar. The barrel drifts into the distance. Nothing else can be seen.] "
"The comic shows a young boy floating in a barrel in an ocean that doesn't have a visible end. It comments on the unlikely optimism and perhaps naïveté people sometimes display. The boy is completely lost and seems hopelessly alone, without any plan or control of the situation. Yet, rather than afraid or worried, he is instead quietly curious: "I wonder where I'll float next?" Although not necessarily the situation in this comic, this is a behavior people often exhibit when there is nothing they can do about a problematic situation for a long time; they may have given up hope or developed a cavalier attitude as a coping mechanism. The title text expands on the philosophical content, with the boy representing the average human being: wandering through life with no real plan, quietly optimistic, always opportunistic and clueless as to what the future may hold. The isolation of the boy may also represent the way in which we often feel lost through life, never knowing quite where we are, believing that there is no one to whom to turn. This comic could also reflect on Randall's feelings towards creating xkcd in the first place; unsure of what direction the web comic would turn towards, but hopeful that it would eventually become the popular web comic that we know today. This is the first in a six-part series of comics whose parts were randomly published during the first several dozen strips. The series features a character that is not consistent with what would quickly become the xkcd stick figure style. The character is in a barrel. In 1110: Click and Drag there is a reference to this comic at 1 North, 48 East . After Randall released the full The Boy and his Barrel story on xkcd, it has been clear that the original Ferret story should also be included as part of the barrel series. The full series can be found here . They are listed below in the order Randall chose for the short story above: [A boy sits in a barrel which is floating in an ocean.] Boy: i wonder where i'll float next? [A smaller frame with a zoom out of the boy in the barrel seen from afar. The barrel drifts into the distance. Nothing else can be seen.] "
2
"Petit Trees (sketch)"
"Petit Trees (sketch)"
"https://www.xkcd.com/2"
"https://imgs.xkcd.com/comics/tree_cropped_(1).jpg"
"https://www.explainxkcd.com/wiki/index.php/2:_Petit_Trees_(sketch)"
"[Two trees are growing on opposite sides of a sphere.] "
"This comic does not present a particular point; it is just a picture drawn by Randall . The Little Prince (in French Le Petit Prince) is a novella written by Antoine de Saint-Exupéry in 1943, about the titular Little Prince, who lives on an asteroid and visits other inhabited asteroids and eventually the Earth. The book is filled with drawings of the asteroid, the prince, and the travels they make. It is noted how, on occasion, baobab trees can begin to grow on these asteroids, and should they not be immediately uprooted, the growth of their roots would tear the asteroid apart. In this drawing, the roots are encircling the sphere, rather than piercing it, as Le Petit Prince describes. The Little Prince has later been referenced both in 618: Asteroid and in 1350: Lorenz at the end of the space trip branch. It was also referenced to in the What If article Leap Seconds . [Two trees are growing on opposite sides of a sphere.] "
3
"Island (sketch)"
"Island (sketch)"
"https://www.xkcd.com/3"
"https://imgs.xkcd.com/comics/island_color.jpg"
"https://www.explainxkcd.com/wiki/index.php/3:_Island_(sketch)"
"[A color sketch of an island.] "
"This comic does not present a particular point; it is just a picture drawn by Randall . The title text may be a play on the classical "Hello, world!" program, traditionally a first program when learning a new programming language. [A color sketch of an island.] "
4
"Landscape (sketch)"
"Landscape (sketch)"
"https://www.xkcd.com/4"
"https://imgs.xkcd.com/comics/landscape_cropped_(1).jpg"
"https://www.explainxkcd.com/wiki/index.php/4:_Landscape_(sketch)"
"[A sketch of a landscape with sun on the horizon.] [There is text from the checkered paper at the top:] From Page No.__ "
"This comic does not present a particular point; it is just a picture drawn by Randall. There is a joke in the title text that a river, made of water, is flowing through the ocean, which is also made of water. It is also worth noting that the sketch, when flipped vertically, maintains the appearance of having the sea on the bottom and sky on top, although the setting sun is on the wrong part of the horizon. Similar to works of M. C. Escher , this picture takes visual components of a typical scene and combines then in ways that appear to work well on a small scale, but would never combine that way in real life and do not make sense in the larger context of the image. The clouds are casting shadows on the sky. [A sketch of a landscape with sun on the horizon.] [There is text from the checkered paper at the top:] From Page No.__ "
5
"Blown apart"
"Blown apart"
"https://www.xkcd.com/5"
"https://imgs.xkcd.com/comics/blownapart_color.jpg"
"https://www.explainxkcd.com/wiki/index.php/5:_Blown_apart"
"[A black number 70 sees a red package. This small panel is partly overlaid on the next larger panel, which is shifted down.] 70 70: hey, a package! [The package explodes in a cloud of brown smoke. This panel is both behind the first in the top left corner, and below the last panel, which has been laid on top of that corner.] BOOM [There are a red 7, a green 5, and a blue 2 lying near a scorched mark on the floor.] 7 5 2 "
"This comic is a mathematical and technical joke involving prime numbers and primary colors. In the comic, an anthropomorphic black-colored number 70 sees a package, but it turns out to be a letter bomb that explodes when opened. The result is pieces of the number scattered about. The specific pieces are a red-colored 7 , a green-colored 5 , and a blue-colored 2 . The title text explains the logic for splitting 70 into 7, 5, and 2; as with many of the earlier comics, the title text explains the joke rather than adding to it. 7*5*2 is a prime factorization of the number 70. Prime numbers are numbers that cannot be divided by any number other than itself and 1. Factors of a number are numbers that can be multiplied together to produce that number (i.e. 2×5×7 = 70). 70 has other factors, including 1, 10, 14, 35, and 70, but 2, 5, and 7 are the only factors that are prime. All other factors of 70 can be formed by choosing zero, two, or three of the prime factors and multiplying them together. An implication of this comic is that prime numbers would be immune to explosions, as they are already their smallest parts. Although not explicitly called out, the colors of the numbers also seem to have been blown apart. Red, green, and blue are the primary colors in the additive color model. These colors mixed in pairs produce cyan, magenta, and yellow, which are primary colors in the subtractive color model. The removal of all additive primary colors, or conversely, the combination of all subtractive primary colors, produces black, which is the color of the original 70 (according to the official transcript , although it looks dark blue in the drawing). The comic is somewhat misleading in that red, green, and blue do not compose black in either color model, but the difference between the two models is not widely understood (most still view the additive primaries as red, yellow, and blue). [A black number 70 sees a red package. This small panel is partly overlaid on the next larger panel, which is shifted down.] 70 70: hey, a package! [The package explodes in a cloud of brown smoke. This panel is both behind the first in the top left corner, and below the last panel, which has been laid on top of that corner.] BOOM [There are a red 7, a green 5, and a blue 2 lying near a scorched mark on the floor.] 7 5 2 "
6
"Irony"
"Irony"
"https://www.xkcd.com/6"
"https://imgs.xkcd.com/comics/irony_color.jpg"
"https://www.explainxkcd.com/wiki/index.php/6:_Irony"
"[A panel only with text. The last text is written below a line in all capital letters.] When self-reference, irony, and meta-humor go too far A CAUTIONARY TALE [Cueball talks to to his Cueball-like friend.] Cueball: This statement wouldn't be funny if not for irony! [Cueball laughs at his own joke in front of his friend.] Cueball: ha ha Friend: ha ha, I guess. [Again a panel only with text.] 20,000 years later... [A desolate brown badlands landscape with an imposing red sun in the dark blue sky.] "
"It must be part of the human condition that causes us to think that odd statements are sometimes more humorous than those supposed to be funny. Cueball makes a true statement, that his statement is not very funny. However, because he invoked irony and thus makes it self-referential, the sentence is now funny! The other guy (also a Cueball-like character), producing a fake laugh, is probably not so sure that it is actually funny. Now going meta: In 20,000 years, there might be no more humans on earth to find the irony funny anymore. How ironic ! Alternatively, the barren landscape would have occurred regardless of whether someone made the joke, so ironically, the cautionary tale is completely meaningless, although still funny. This is the first xkcd comic showing stick figure people, which eventually becomes a defining characteristic of the future comic series. It is thus also the first comic with Cueball (and the first with Multiple Cueballs ). Note however, that it was actually not the first comic Randall released using either of the above mentioned features, see the trivia below. The "too much perspective" line comes from the visit of Spın̈al Tap to the grave of Elvis Presley . In addition, the perspective theme also invokes the Total Perspective Vortex in The Hitchhiker's Guide to the Galaxy . This is located on the desolate planet Frogstar B, possibly looking not unlike the final image in the comic. Self-references was already used again in 33: Self-reference , and again and again , but never more famously than in 688: Self-Description . [A panel only with text. The last text is written below a line in all capital letters.] When self-reference, irony, and meta-humor go too far A CAUTIONARY TALE [Cueball talks to to his Cueball-like friend.] Cueball: This statement wouldn't be funny if not for irony! [Cueball laughs at his own joke in front of his friend.] Cueball: ha ha Friend: ha ha, I guess. [Again a panel only with text.] 20,000 years later... [A desolate brown badlands landscape with an imposing red sun in the dark blue sky.] "
7
"Girl sleeping (Sketch -- 11th grade Spanish class)"
"Girl sleeping (Sketch -- 11th grade Spanish class)"
"https://www.xkcd.com/7"
"https://imgs.xkcd.com/comics/girl_sleeping_noline_(1).jpg"
"[Girl sleeping on her side, facing away from view.] "
"This comic does not present a particular point; it is just a picture drawn by Randall. It is just what the title says - a sketch of a girl sleeping drawn during a Spanish class. According to the title text, she is also on the floor. [Girl sleeping on her side, facing away from view.] "
8
"Red spiders"
"Red spiders"
"https://www.xkcd.com/8"
"https://imgs.xkcd.com/comics/red_spiders_small.jpg"
"https://www.explainxkcd.com/wiki/index.php/8:_Red_spiders"
"[Many six-legged red spiders standing on and hanging from cuboids. The cuboids hang in the air with no visible means of support. Some of the spiders have made a bridge out of themselves.] "
"The early comics often feature a style different to what would become the signature xkcd stick-figure style. This comic is the first in an arc of comics, spaced out over 3 years (so far), in which Red Spiders are seen attacking humans. Its objective is not to be funny, philosophical, or scientifically interesting; it just tells a story, in a Questionable Content -esque way. Interestingly, the red spiders actually more closely resemble opiliones, the order of arachnids that includes the Daddy Longlegs, and which are actually more closely related to mites than to spiders. Of course, the number of legs is incorrect. The full series of Red Spiders comics: [Many six-legged red spiders standing on and hanging from cuboids. The cuboids hang in the air with no visible means of support. Some of the spiders have made a bridge out of themselves.] "
9
"Serenity is coming out tomorrow"
"Serenity is coming out tomorrow"
"https://www.xkcd.com/9"
"https://imgs.xkcd.com/comics/firefly.jpg"
"https://www.explainxkcd.com/wiki/index.php/9:_Serenity_is_coming_out_tomorrow"
"[Several stick figures stand side by side in a lineup. A forlorn male in a coat, a male with combed hair, a male with spiky hair and arms outstretched enthusiastically, a female with long hair and cornrows, a shorter female with stringy hair falling over her face, an enthusiastic female with arms raised in celebration with shorter hair, a male with short hair and a goatee and hands on hips, a female with curly hair wearing a dress, and a stern-looking man with flyaway hair.] "
"This comic is about the release of the movie Serenity , which was the followup to Joss Whedon 's TV show, Firefly , which was cancelled by Fox after only one season. Plus, three episodes were not shown on Fox but debuted on Sci Fi Channel in the UK. The show was followed by a devoted number of fans who were outraged by the cancellation of the show. High DVD sales and strong fan support allowed the follow up film Serenity to be created, which tied up many of the loose ends that Firefly left open, such as the cause of River 's abilities and the origins of the Reavers . The image shows the main characters of Firefly. From left to right: This is the first xkcd with adorned stick figures (e.g. hair, coats, etc.) to represent distinct characters, which later becomes a standard motif of the comic. Nathan Fillion , Summer Glau , and Jewel Staite , the actors who play Mal, River, and Kaylee respectively, show up later in Randall's series The Race . [Several stick figures stand side by side in a lineup. A forlorn male in a coat, a male with combed hair, a male with spiky hair and arms outstretched enthusiastically, a female with long hair and cornrows, a shorter female with stringy hair falling over her face, an enthusiastic female with arms raised in celebration with shorter hair, a male with short hair and a goatee and hands on hips, a female with curly hair wearing a dress, and a stern-looking man with flyaway hair.] "
10
"Pi Equals"
"Pi Equals"
"https://www.xkcd.com/10"
"https://imgs.xkcd.com/comics/pi.jpg"
"https://www.explainxkcd.com/wiki/index.php/10:_Pi_Equals"
"[A huge π to the left, then a large equal-to sign, and then five rows of text.] π = 3.14159265 3589793help imtrappedin auniversefac tory7108914..."
"There are two possible references here. One is from the book Contact by Carl Sagan, where the existence of God was shown in the last chapter to be encoded in the digits of pi . The other is an old joke of a fortune cookie with a fortune that reads, "Help! I'm trapped in a fortune cookie factory!" Similar jokes are often repeated for any mass-manufactured personalized item, often implying that the worker who made the item is working in a sweatshop somewhere or is literally trapped inside a factory and calling for help via the items they produce. This joke is also referenced in 327: Exploits of a Mom 's title text, where Mrs. Roberts daughter 's name is "Help I'm trapped in a driver's license factory." The most literal interpretation of the joke would be that some being who helped to create the universe in a "universe factory" snuck a message into the digits of pi (a number that has an endlessly long decimal that never repeats) asking for help to get out. Mathematical concepts being manufactured in a factory is the main mental image here. One can't help but wonder if the primordial beings who labored on the universe to produce things like the gravitational constant and pi have a labor union. Judging by the fact that they're calling for help, it seems they don't. Since pi never ends and does not follow any sort of known pattern, if each number pair were assigned a letter from the alphabet, or if it was converted to base-26 (or preferably ASCII or some other form of text encoding, if you desire capitalization and punctuation), the entire works of Shakespeare, as well as any other expressible piece of information, including the message in this comic, could presumably be found (it is not really known that pi really has this property , but the absence of this property would in itself be an extraordinary coincidence); although the probability of finding any given string of numbers within a calculable range of digits of pi diminishes rapidly as the string length increases . In the novel Contact by Carl Sagan , he includes a "Signature of God" (There was a link here, but the page no longer exists). In brief, the signature consists of a very long string of 1s and 0s far out (after some 10^20 seemingly random numbers) in the base-11 expansion of pi that when arranged in a square of a specific size yields a clear drawing of a circle with a diameter of several hundred digits. The existence of this pattern was hinted to the protagonist by a member of an advanced alien civilization as being encoded in physics by an even more advanced civilization with the ability to create universes. Interestingly enough, this could also work for pictures: if you assign a set of nine numbers to equal an RGB hexadecimal color value, eventually you will find the Mona Lisa. In the title text, Randall notes that this became one of his most famous comics (at the time it was re-released on the new xkcd site on the 1st of January 2006.) He also notes that it was one of his first drawings for the site (it was the 11th posted originally). See trivia below. [A huge π to the left, then a large equal-to sign, and then five rows of text.] π = 3.14159265 3589793help imtrappedin auniversefac tory7108914..."
11
"Barrel - Part 2"
"Barrel - Part 2"
"https://www.xkcd.com/11"
"https://imgs.xkcd.com/comics/barrel_mommies.jpg"
"https://www.explainxkcd.com/wiki/index.php/11:_Barrel_-_Part_2"
"[A boy sits in a barrel which is floating in an ocean.] Boy: none of the places i floated had mommies. "
"Like in the previous comic in the Barrel series, the boy is floating in the ocean in a barrel. The previous comic made a point about the uncertainty of life; here, the boy's lament at not finding a mother is pure sentimentality, as accentuated by the title text. According to Freud, the first stage of psycho-sexual development is the Oral Stage, which relates to a baby's relationship with its mother. The realization that 'mommy' cannot be found is the first point at which a person learns to stop trusting the world and realizes that the world is not always comforting and safe. This is the second in a six-part series of comics whose parts were randomly published during the first several dozen strips. The series features a character that is not consistent with what would quickly become the xkcd stick figure style. The character is in a barrel. After Randall released the full The Boy and his Barrel story on xkcd, it has been clear that the original Ferret story should also be included as part of the barrel series. The full series can be found here . But below they are listed in the order Randall has put them in his collection linked to above: [A boy sits in a barrel which is floating in an ocean.] Boy: none of the places i floated had mommies. "
12
"Poisson"
"Poisson"
"https://www.xkcd.com/12"
"https://imgs.xkcd.com/comics/poisson.jpg"
"https://www.explainxkcd.com/wiki/index.php/12:_Poisson"
"[Cueball is talking to Black Hat. Cueball has his mouth wide open and has both of his arms up.] Cueball: I'm a poisson distribution! [Same scene, except Cueball has only one arm up.] Cueball: Still a Poisson distribution! Black Hat: what the hell, man. Why do you keep saying that? [Cueball's face is gone, and he is not holding any arms up.] Cueball: Because I'm totally a poisson distribution. Black Hat: I'm less than zero. [Cueball is gone. Black Hat is now whistling.] "
"Cueball expresses himself as a Poisson distribution . A Poisson distribution is a distribution that shows the probability of a given number of events occurring in a fixed interval of time or space. The X axis typically represents the "number of events" while the Y axis is a decimal representing the probability (i.e. 0.5 for 50% probability) a given number of events will occur in that fixed interval of time or space. It is commonly represented by a bar graph or a scatter graph (sometimes with a line connection to show a trend, even though there is no actual value for non-integers). What's important to note for this comic is that this distribution only has data points on non-negative integers and is not continuous through decimal numbers or (as the image text tells us) negative numbers because events can't occur 0.3 of a time, or −2 times. After implying that the concept of a person being a mathematical distribution is irrational, Black Hat suggests he is "less than zero". Since the Poisson distribution doesn't exist or has no value at negative values, Cueball either leaves or disappears magically. Hence, the punchline is the same as the title text: Cueball doesn't exist to Black Hat anymore, because he has a value less than zero. Another one of the early comics where Randall explains the joke in the title text. Also, because a Poisson point process is memoryless, the figure claiming to be the distribution may simply be repeating the fact as a reference to this. [Cueball is talking to Black Hat. Cueball has his mouth wide open and has both of his arms up.] Cueball: I'm a poisson distribution! [Same scene, except Cueball has only one arm up.] Cueball: Still a Poisson distribution! Black Hat: what the hell, man. Why do you keep saying that? [Cueball's face is gone, and he is not holding any arms up.] Cueball: Because I'm totally a poisson distribution. Black Hat: I'm less than zero. [Cueball is gone. Black Hat is now whistling.] "
13
"Canyon"
"Canyon"
"https://www.xkcd.com/13"
"https://imgs.xkcd.com/comics/canyon_small.jpg"
"https://www.explainxkcd.com/wiki/index.php/13:_Canyon"
"[Two guys, both Cueball-like, are standing at a cliff's edge.] Friend: What time is it? [Cueball looks at his watch in silence.] [Cueball looks up.] Cueball: Now. [The full scene is shown: the two men (barely visible) are standing at the lip of a huge canyon in a rocky, barren landscape. A pock-marked moon and a ringed planet are visible in the burgundy-colored sky.] [The two guys are again seen standing at what is now known to be the lip of the canyon.] Friend: That's a pretty boring answer. [Same scene as before.] Cueball: Is not. [Same scene.] Cueball: It's the least boring answer imaginable. "
"This is one of the early comics that explores a theme xkcd returns to often: the wonder around us, if we would just look. Cueball and his friend (who also looks like Cueball) are having a discussion. After the friend asks Cueball what the time is, Cueball simply states that it is "now." Then there is a beat panel showing the two standing at the lip of a great canyon drawn in detail and color. The friend claims that "now" is a boring answer, since it's a tautology , a functionally useless answer, and a bad joke all at the same time. Cueball, however, asserts that "now" is the least boring answer he could give. It is typical for human beings to focus on mundane concerns, like a meeting they might be late for or a bus they have to catch, and take their familiar environment for granted, no matter how fabulous it might have been at first sight. The title text explains that they stand on the lip of the canyon, which may not be clear if you do not look very carefully at the color drawing. There are two tiny stick figures at the edge of the canyon, near the center of the panel. On the other six panels, there is just a ragged line, which thus obviously is this lip of the canyon. [Two guys, both Cueball-like, are standing at a cliff's edge.] Friend: What time is it? [Cueball looks at his watch in silence.] [Cueball looks up.] Cueball: Now. [The full scene is shown: the two men (barely visible) are standing at the lip of a huge canyon in a rocky, barren landscape. A pock-marked moon and a ringed planet are visible in the burgundy-colored sky.] [The two guys are again seen standing at what is now known to be the lip of the canyon.] Friend: That's a pretty boring answer. [Same scene as before.] Cueball: Is not. [Same scene.] Cueball: It's the least boring answer imaginable. "
14
"https://www.xkcd.com/14"
"[A colored drawing of a hilly, grassy landscape. Cueball is leaning against a tree.] Cueball: Sometimes I just can't get outraged over copyright law "
"Following the copyright wars can be tiring and irritating, but faced with the beauty of nature, the importance of such matters withers away. Copyright is a monopoly granted by governments to writers, artists, performers, or corporations to control the distribution, copying, and performance of their creative expression or the creative expression of artists under contract with them. Before the digital age, it allowed authors and publishers an opportunity to profit from their work without fear of someone making copies and selling them for their gain. In the digital age, when the cost and difficulty of copying has been reduced to near zero, it hasn't worked so well, especially for publishers of music and video. Industry trade organizations like the RIAA and MPAA have fought to preserve their old business models, lobbying for new laws to protect their income streams in an age where anyone can copy an MP3 file or a DVD quickly and cheaply. This has involved ordering web sites to take down "infringing" material (and many times material that wasn't infringing), media campaigns comparing file copiers to folks who commit murder on the high seas, and suing artists and writers who have used samples of music or movies in their own work. The RIAA has claimed that rampant illegal copying hurts the artists whose work is copied, as it cuts into the artists' royalty payments; many artists, on the other hand, complain that the RIAA's accounting practices have denied them their fair royalties for decades anyway, and that increased copying leads to increased fans and money through direct sales and is actually better for them than the RIAA. It's a vicious war. An early casualty in the copyright wars was Napster ; a later casualty was the concept of DRM (Digital Restrictions Malware) on recorded music and/or elsewhere. The wars have been going on since the early 1990s and show no sign of slowing down. Slashdot and Boing Boing are two news aggregation websites that cover (among other things) the copyright wars in detail, usually biased against the RIAA, MPAA, and similar organizations. [A colored drawing of a hilly, grassy landscape. Cueball is leaning against a tree.] Cueball: Sometimes I just can't get outraged over copyright law "
15
"https://www.xkcd.com/15"
"[A man is standing on top of a green dinosaur and holding reins to the dinosaur's head.] Man: Before you talk to me, I should warn you: I am kind of strange "I bet she's cool. I mean, she has a dinosaur! I'm gonna update this MWF for a while and see how that works. " "
"Here, a man is seen riding on a Brontosaurus ? (This is according to the official transcript on xkcd, including the questionmark.) Later Randall would probably have called it an Apatosaurus , see the Category:Apatosaurus . The joke here is that this person feels the need to point out that they are "kind of strange," even though one might think that that would be clear from the fact that they are riding an extinct and potentially dangerous creature. In the title text the man continues by saying Just thought you should know . Just a service notice. In 650: Nowhere Megan is seen imagining herself riding an Apatosaurus. [A man is standing on top of a green dinosaur and holding reins to the dinosaur's head.] Man: Before you talk to me, I should warn you: I am kind of strange "I bet she's cool. I mean, she has a dinosaur! I'm gonna update this MWF for a while and see how that works. " "
16
"Monty Python -- Enough"
"Monty Python -- Enough"
"https://www.xkcd.com/16"
"https://imgs.xkcd.com/comics/monty_python.jpg"
"https://www.explainxkcd.com/wiki/index.php/16:_Monty_Python_--_Enough"
"[The comic is drawn on blue-ruled graph paper.] [A Cueball with raised hands talks to two other Cueball-like characters and one Megan.] Cueball: We are the Knights who say... Ni!! Cueballs and Megan: hahaha [There is only text in the second panel] Does anyone else find it funny that decades later, people are still quoting --word-for-word-- a group loved for their mastery of shock, the unexpected, and defiance of convention? [Two Cueballs are looking at a hairy guy.] Hairy guy: We are the Knights who... oh, God, I'm so sorry [Close up of hairy guy.] Hairy guy: So sorry, the car just came too fast and [Words crumpled inside the panel, there's barely enough space for the hairy guy to the right and below the text. The last two words need to be to the right of him.] Hairy guy: She was right there and I saw her and then it was a blur and so much I ran to help didn't know what she wasn't moving I'm so sorry Hairy guy: so sorry [The two Cueballs are looking again at the hairy guy.] Hairy guy: Anyway, yeah, Knights who say "Ni." [The last panel is also almost only text. The text is centered. Below is a drawing that looks a flat infinity sign with two small lines at the center.] H on or Monty Python: promote surreal humor. "
"This comic refers to the classic British sketch comedy group Monty Python , active primarily during the 1970s and early 1980s but also partly reunified in 2014 , whose humor style was frequently based on surreal jokes that subverted sense and logic. Their sketches are so popular that, as noted in the comic, many fans can repeat the dialog word-for-word, and often do. This comic points out the inherent irony of repeating a surrealist sketch, as surrealist humor primarily depends on presenting something the audience does not expect. By repeating the sketch verbatim among those who have already seen it, the listeners know and expect the punchlines and jokes. This is akin to a common ironic concept of a teenager who wants to rebel against conformity by doing all the things their friends are also doing. The sketch in question here is the " Knights who say Ni " sketch from the film Monty Python and the Holy Grail , about a group of knights who protect certain sacred words, including the word "Ni" (pronounced like the word "knee," but shortened and with more staccato). The comic suggests that readers continue in the surreal traditions of Monty Python, and provides an example: The character in panels 3-6 interrupts his retelling of the sketch with what appears to be a traumatic recalling of the time he saw someone run a woman over with their car and kill her, before returning to the sketch. The surreal humor is that the character dismisses the significant and serious comment he has just made by returning to the sketch as if nothing happened. The title text refers to how fans of Monty Python can go for long periods of time simply quoting the sketches, as one person quotes a sketch, another recognizes it and says another quote without context, assuming everyone will recognize it. Perhaps a more contemporary version of this might be The Simpsons or Family Guy quote frenzies. [The comic is drawn on blue-ruled graph paper.] [A Cueball with raised hands talks to two other Cueball-like characters and one Megan.] Cueball: We are the Knights who say... Ni!! Cueballs and Megan: hahaha [There is only text in the second panel] Does anyone else find it funny that decades later, people are still quoting --word-for-word-- a group loved for their mastery of shock, the unexpected, and defiance of convention? [Two Cueballs are looking at a hairy guy.] Hairy guy: We are the Knights who... oh, God, I'm so sorry [Close up of hairy guy.] Hairy guy: So sorry, the car just came too fast and [Words crumpled inside the panel, there's barely enough space for the hairy guy to the right and below the text. The last two words need to be to the right of him.] Hairy guy: She was right there and I saw her and then it was a blur and so much I ran to help didn't know what she wasn't moving I'm so sorry Hairy guy: so sorry [The two Cueballs are looking again at the hairy guy.] Hairy guy: Anyway, yeah, Knights who say "Ni." [The last panel is also almost only text. The text is centered. Below is a drawing that looks a flat infinity sign with two small lines at the center.] H on or Monty Python: promote surreal humor. "
17
"What If"
"What If"
"https://www.xkcd.com/17"
"https://imgs.xkcd.com/comics/what_if.jpg"
"https://www.explainxkcd.com/wiki/index.php/17:_What_If"
"[A large black circle (drawn on grid paper) with white bubbles inside it, filled with hearts, question marks, and stick figure couples. The hearts are colored red.] [Bottom left circle - stick figure couple with a heart] [Top right circle - with couple:] what if this isn't everything it should be? [Two circles left of top-right:] i'm not even sure how i feel [One circle right of top-right:] what if i'm making a mistake? "One of my best friends just got engaged. I really, truly think they're going to be very happy together." The friends referred to are Scott and Sarah. "
"This comic features a man and a woman in a romantic setting, surrounded by a fractal combination of love and doubts; an arrangement based on the Apollonian gasket construction. Three circles are drawn tangent to each other, then additional circles are added that are tangent to three existing circles (without overlapping), ad infinitum. Randall's character design wasn't yet fully settled. Considering that Megan arguably was introduced two comics ago, and that the man has some hair, the couple might or might not be interpreted as Cueball and Megan. Randall's later blog and book have the same name, what if? , though with very different meaning. [A large black circle (drawn on grid paper) with white bubbles inside it, filled with hearts, question marks, and stick figure couples. The hearts are colored red.] [Bottom left circle - stick figure couple with a heart] [Top right circle - with couple:] what if this isn't everything it should be? [Two circles left of top-right:] i'm not even sure how i feel [One circle right of top-right:] what if i'm making a mistake? "One of my best friends just got engaged. I really, truly think they're going to be very happy together." The friends referred to are Scott and Sarah. "
18
"Snapple"
"Snapple"
"https://www.xkcd.com/18"
"https://imgs.xkcd.com/comics/snapple.jpg"
"https://www.explainxkcd.com/wiki/index.php/18:_Snapple"
"[Above the frame:] This one is entirely James' fault. [Two Cueball-like guys are standing and talking.] Cueball: Here, take a bite of this Snapple. Friend: food! [Cueball's friend takes a bite.] Friend: Ow! What is this? Clink [The panel switches to Cueball.] Cueball: It's an apple infused with tin. [Beat panel. A wide shot of the two.] [Same scene, except the panel is lightly shaded and the is a box above saying:] Those of you who know your periodic table should be laughing right about now. "
"Cueball hands another Cueball-like guy an apple calling it a snapple. When the guy bites into it, his teeth go clink against the apple's metal surface; Cueball has infused the apple with tin. The fourth panel is a silent wide shot, perhaps suggesting the joke was met with silence as a weak joke . As a meta-joke, the final panel might jokingly suggest that the silence is because those unfamiliar with the periodic table of elements don't get the joke. The joke in this comic is pretty self-explanatory, especially given that the title text continues the trend in early xkcd comics of explaining the joke. Tin is a metallic element whose abbreviation on the periodic table is "Sn" (as the Latin word for tin is "stannum"). Thus, the apple is a "Sn-apple." Snapple is a brand of beverages -- mostly bottled juices and teas -- whose name is based on a carbonated apple juice they once produced ("snappy apple"). James (in the caption) presumably once made a joke to Randall about tin or Snapple or both. [Above the frame:] This one is entirely James' fault. [Two Cueball-like guys are standing and talking.] Cueball: Here, take a bite of this Snapple. Friend: food! [Cueball's friend takes a bite.] Friend: Ow! What is this? Clink [The panel switches to Cueball.] Cueball: It's an apple infused with tin. [Beat panel. A wide shot of the two.] [Same scene, except the panel is lightly shaded and the is a box above saying:] Those of you who know your periodic table should be laughing right about now. "
19
"George Clinton"
"George Clinton"
"https://www.xkcd.com/19"
"https://imgs.xkcd.com/comics/george_clinton.jpg"
"https://www.explainxkcd.com/wiki/index.php/19:_George_Clinton"
"[George Clinton uses a baton to point to the bottom of two equations on a blackboard. There is one more equation and a diagram on another blackboard to the right, which is cut off. There is text above:] I once tried to start the urban legend that George Clinton has a B.A. in mathematics [On the left blackboard there are two formulas:] L(F(t) = F(s) = ∫ ∞ 0 f(t)e -st dt L -1 (F(s)) = f(t) = ∫ ∞ 0 F(t)e st dt [On the right blackboard there is part of a formula and a diagram with an x-y scale and three other lines touching down to the base. Above these lines are some numbers that are partly indecipherable.] γ n = 2 n/12 K 0 2 3 ⌊⌊⌊⌊ [Below George and the blackboards is text:] ...but I wanted it to be true so badly that I started believing it myself."
"George Clinton is an American musician most famous for his funk music and wild hair style. His recorded music features themes of space, sci-fi, technology, and futurism. An example of his work most appropriate to this comic is the song "Mathematics" from the 1996 album T.A.P.O.A.F.O.M. (The awesome power of a fully operational mothership). "I count the moments we're apart. And add them up mathematically and multiply them by the kisses supposedly I've been missing. Divided by the attention not to mention the affection. Subtract that from your gross potential and see I ain't missin' none. Cause any percentage of you is as good the whole pie. Any fractions thereof brings dividends of interest. Any percentage of you is as good as the whole pie. Any fractions thereof brings dividends of love. I take the square root and get boxed in every time. When I know the shortest distance between two points is in a straight line. I'ma go into you, I'ma come into you two times, and carry the fun over the one to where we equal one.” (Chorus 2x) As Randall says, he had attempted to spread around an urban legend that George Clinton had a Bachelor of Arts degree in mathematics. However, the more Randall thought about this rumor, the more he found himself believing it was true. This behavior is related to pseudologia fantastica , which is more commonly known as pathological or compulsive lying. This comic references the associated behavior that an "individual may be aware they are lying, or may believe they are telling the truth, being unaware that they are relating fantasies." These individuals may eventually stop the lie as demonstrated by the title text, which indicates that at some later time, the individual realized that the rumor was not true, but wishes it to be so. This may also be a reference to James Thurber's 13 clocks, in which a character called the Golux has the following exchange with the main character: "When I was young I told a tale of buried gold, and men from leagues around dug in the woods. I dug myself." "But why?" "I thought the tale of treasure might be true." "You said you made it up." "I know I did, but I didn't know I had. I forget things, too." The equations on the board are laplace transforms of functions. [George Clinton uses a baton to point to the bottom of two equations on a blackboard. There is one more equation and a diagram on another blackboard to the right, which is cut off. There is text above:] I once tried to start the urban legend that George Clinton has a B.A. in mathematics [On the left blackboard there are two formulas:] L(F(t) = F(s) = ∫ ∞ 0 f(t)e -st dt L -1 (F(s)) = f(t) = ∫ ∞ 0 F(t)e st dt [On the right blackboard there is part of a formula and a diagram with an x-y scale and three other lines touching down to the base. Above these lines are some numbers that are partly indecipherable.] γ n = 2 n/12 K 0 2 3 ⌊⌊⌊⌊ [Below George and the blackboards is text:] ...but I wanted it to be true so badly that I started believing it myself."
20
"Ferret"
"Ferret"
"https://www.xkcd.com/20"
"https://imgs.xkcd.com/comics/ferret.jpg"
"https://www.explainxkcd.com/wiki/index.php/20:_Ferret"
"[A color drawing of a ferret with airplane wings and tail on it.] [Cueball and his Cueball-like friend (to the left) are talking.] Friend: Why on earth did you make those wings? You don't seriously think they could let your ferret fly, right? Cueball: I... of course not. [They continue to talk.] Cueball: That would be pretty dumb. It's just, uh... ...a Halloween costume. Friend: oh, okay. [They continue to talk. The head of the ferret can be seen to the far right on a table.] Friend: Besides, who would want a pet to fly anyway? Cueball: Yeah. Pretty lame, huh? [The friend leaves the frame while Cueball stays. The ferret cannot be seen.] Friend: Anyway, let's go play video games. [Cueball stands behind after his friend has left. He looks back towards his ferret.] [Cueball imagines his ferret flying over the ocean near the beach using his makeshift wings while holding his ferret.] "
"Cueball 's (Cueball-like) friend makes fun of his imagination that involves a flying ferret, and then suggests to go play video games instead. This shows the irony of his definition of "imagination." He makes fun of Cueball's creative fantasy while instead opting for a mass-produced fantasy. The fact that Cueball lies about his goal could be a commentary on abandoning dreams to avoid confronting societal expectations. The title text refers to the fact that Randall's brother in real life had such a pet ferret. Originally, Randall drew this comic while the ferret was still alive, and then it passed away in between his posting it on LiveJournal and reposting it with a title text on the new xkcd site. He now wishes that it will rest in peace. The ferret returns in 31: Barrel - Part 5 and did in this way become part of the Barrel series . This has also been canonized by Randall as can be seen on this web-archive version of xkcd: The Boy and his Barrel . The full series can be found here . But below they are listed in the order Randall has put them in his collection linked to above: [A color drawing of a ferret with airplane wings and tail on it.] [Cueball and his Cueball-like friend (to the left) are talking.] Friend: Why on earth did you make those wings? You don't seriously think they could let your ferret fly, right? Cueball: I... of course not. [They continue to talk.] Cueball: That would be pretty dumb. It's just, uh... ...a Halloween costume. Friend: oh, okay. [They continue to talk. The head of the ferret can be seen to the far right on a table.] Friend: Besides, who would want a pet to fly anyway? Cueball: Yeah. Pretty lame, huh? [The friend leaves the frame while Cueball stays. The ferret cannot be seen.] Friend: Anyway, let's go play video games. [Cueball stands behind after his friend has left. He looks back towards his ferret.] [Cueball imagines his ferret flying over the ocean near the beach using his makeshift wings while holding his ferret.] "
21
"Kepler"
"Kepler"
"https://www.xkcd.com/21"
"https://imgs.xkcd.com/comics/kepler.jpg"
"https://www.explainxkcd.com/wiki/index.php/21:_Kepler"
"[Two Cueball-like guys stand in an aisle in a store.] Cueball: Nice store. How do you keep the floors so clean? Store manager: Oh, we hired this dude named Kepler, he's really good. Hard worker. Doesn't mind the monotony. Sweeps out the same area every night. "
"A Cueball-like guy asks Cueball , the store manager, how they keep the store so clean, and he is told that they have hired Kepler, a hard worker who doesn't mind the monotony and sweeps out the same area every night. Johannes Kepler was a German mathematician, astronomer, and astrologer, best known for his laws of planetary motion. By using Tycho Brahe 's observations of our solar system (Brahe gave Kepler the job of observing and explaining the motion of the planet Mars), Kepler was able to deduce that planets in the system do not move in a circular orbit around the Sun, but rather in an elliptical one. In doing so, he directly contradicted Brahe's own conviction that the Earth was the centre of the universe. According to Kepler's Second Law , "A line joining a planet and the Sun sweeps out equal areas during equal intervals of time," somewhat akin to sweeping a broom over the floor. In the comic, the janitor Kepler also sweeps the same area, although in this case, "area" is used in the sense of "surface" (of floor) rather than in the purely mathematical sense. It is also very monotonous, like a planet's set orbit, but Kepler doesn't mind this. The comic could also be seen as a subtle reference to the Kepler space telescope that was searching for exoplanets (planets outside the Solar system) from March 2009 to August 2013, by looking at exactly the same spot in the night sky over and over again. Even though the telescope was not launched until 4 years after this comic was published, the details of Project Kepler had been disclosed by NASA press releases as early as 2001 . The title text assumes that the reader is scientifically illiterate and won't understand the joke, which is ironic, considering how xkcd came to be known for embracing STEM fields and nerdiness in general. [Two Cueball-like guys stand in an aisle in a store.] Cueball: Nice store. How do you keep the floors so clean? Store manager: Oh, we hired this dude named Kepler, he's really good. Hard worker. Doesn't mind the monotony. Sweeps out the same area every night. "
22
"Barrel - Part 3"
"Barrel - Part 3"
"https://www.xkcd.com/22"
"https://imgs.xkcd.com/comics/barrel_whirlpool.jpg"
"https://www.explainxkcd.com/wiki/index.php/22:_Barrel_-_Part_3"
"[A large and deep vortex is in the center; spinning water covers the whole panel. A boy in a floating barrel is near the edge, apparently about to be sucked in.] Boy: wow! "
"In the first two comics in the Barrel series, the boy is floating in the ocean in a barrel, making fairly innocent points about life's uncertainty. In this comic, the view has zoomed out considerably, and the boy is seen to be on the edge of a gigantic whirlpool . Thus, there is now a palpably heightened sense of danger, though the boy's reaction continues to be innocent wonder. The comic's visual composition is reminiscent of a classic 1919 illustration by Harry Clarke , made for Edgar Allan Poe 's 1841 short story " A Descent into the Maelström ." In the short story, the main character escapes from drowning by using a barrel to escape The Maelström. This is the third in a six-part series of comics whose parts were randomly published during the first several dozen strips. The series features a character who is not consistent with what would quickly become the xkcd stick figure style. The character is in a barrel. After Randall released the full The Boy and his Barrel story on xkcd, it has been clear that the original Ferret story should also be included as part of the barrel series. The full series can be found here . But below they are listed in the order Randall has put them in his collection linked to above: [A large and deep vortex is in the center; spinning water covers the whole panel. A boy in a floating barrel is near the edge, apparently about to be sucked in.] Boy: wow! "
23
"T-shirts"
"T-shirts"
"https://www.xkcd.com/23"
"https://imgs.xkcd.com/comics/t-shirts.jpg"
"https://www.explainxkcd.com/wiki/index.php/23:_T-shirts"
"[A collection of phrases on T-shirts. The first and the last on actual black T-shirts worn by the same person, whose facial expression is more sad on the last one.] I see dumb people As a matter of fact the world does revolve around me I can only please one person per day / today is not your day. You know what your problem is? You're stupid. Get a clue Do I look like a people person? Your village called / they want their idiot back Go away I hate you all Die. Help. Maybe if this T-shirt is witty enough, someone will finally love me. Oh God I'm so alone. "
"This comic satirizes the plethora of "snarky" phrase T-shirts that exist today. In the top-left, the character wears a typical (and real) snark shirt, "I see dumb people" (suggesting that the wearer thinks everyone else is dumb, while being a parody of the phrase "I see dead people" from the movie The Sixth Sense ). Other shirts shown also suggest that the wearer is better than everyone else, and perhaps the shirts increasingly suggest that the wearer is anti-social moving from top to bottom. Near the bottom of the screen, the T-shirts no longer attempt to be witty and simply have straightforward phrases like "go away" and "die". These are exaggerations of the message that the other more-realistic shirts broadcast. The final three shirts are also exaggerated shirts that suggest Randall 's view that people who wear snarky shirts are overcompensating for the fact that they are already alone or perhaps putting up a tough exterior to conceal their sadness that no one would talk to them anyway. Most notably "maybe if this T-shirt is witty enough, someone will finally love me" sums up what Randall thinks snarky shirts really say. There are shirts with this or a similar message, although it is unclear whether they were created before this comic or as a tribute to this comic. In the title text, Randall says that it's depressing how many of the shirts in the comic actually exist in real life, further underlining the point that these shirts are overly arrogant, to the point where one might believe that Randall made them up. This highlights the inadequacy of substance within these T-shirts and the terror they invoke in Randall's mind. [A collection of phrases on T-shirts. The first and the last on actual black T-shirts worn by the same person, whose facial expression is more sad on the last one.] I see dumb people As a matter of fact the world does revolve around me I can only please one person per day / today is not your day. You know what your problem is? You're stupid. Get a clue Do I look like a people person? Your village called / they want their idiot back Go away I hate you all Die. Help. Maybe if this T-shirt is witty enough, someone will finally love me. Oh God I'm so alone. "
24
"Godel, Escher, Kurt Halsey"
"Godel, Escher, Kurt Halsey"
"https://www.xkcd.com/24"
"https://imgs.xkcd.com/comics/godel_escher_kurthalsey.jpg"
"https://www.explainxkcd.com/wiki/index.php/24:_Godel,_Escher,_Kurt_Halsey"
"Drawn during an unending NASA lecture [Two people are talking, one in a hat.] Cueball: it's just so hard to compare kids now with kids in the past. you can't help but to belong to one group or the other. Cueball: and of course every generation seems awful to the one before it. look at quotes from throughout history. Hatted: yeah, and it sure would be nice to have some historical perspective on some of this stuff. I just don't know what to make of it. [Circles are appearing--maybe snow?] Cueball: i guess you do what you can to help the people around you and hope it turns out okay. Cueball: in the end, what else can you do? Hatted: lead a crusade? [We can no longer see the people, just the circles.] it's presentism, man. the idea that historical context is irrelevant, that we understand it all that we need take no warnings from the follies of the past. that we're facing something new. socrates couldn't imagine the internet. but people don't change. [We can start to see a darker circle in the lower right corner.] (The borders between the three panels on this line are cracking.) have you seen those collections of historical pornography? talk about historical context. did you know the first porn photo was bestial in. [inside a circle:] nature? at least that stuff was out of the mainstream [each word in one circle:] no just in history (the three panels have merged into one on each row.) i don't know about you, but [circled] I [uncircled] never even once seen [The circles are highly variable in size now, and pressed up against a larger one on the right side.] [There is mass of circles of different sizes, with some dark fissures in between, against the side of a large circle which we can see part of in the right half of the panel. They look like cells. There's a tiny square in the center of the giant cell.] [We see only the tiny square, centered. It has a few marks inside it.] [Closer, the square is divided into rectangles of different sizes, each of which has text in it.] [Much closer, we can see fragments of the text. Some are sideways, some are cut off, some are too small to read.] machine language translated by principles of isomorphism it is a consequence of the Church-Turing thesis that ... but how do you select the channel you wish to se- thou ... shou ... palin ... stri ... it is a ... crab ... be obvious to one-s ... your great intellectual achievements ... Tortise. Why ... you give this old Tortise ... [Closer still, we can just see a huge sideways s and h.] [Those letters are faded and mixed with a faded version of the next panel.] girls take boys away ... never be further than a phone call and a goosebumped shiver away ... drove all night listening to mix tapes ... the past is just practice [There is a heart at the bottom and, in the lower left, the name Kurt.] [The same as the previous panel, but with the words blurred out to scribbles.] [Jagged, shaded shapes and strands start to fall. Faint panel borders appear again. There is a person on the far right.] (Back to three panels per row.) [Cueball and Megan are standing amid the fragments.] Cueball: There's too much. And so little feels important. [The jagged edge of the shaded area is encroaching on the sides of the panel.] What do you do? [We see them from farther away through a rough hole in the shaded area. Bits continue to fall around them.] [They are holding hands.] "One of a series of strips I drew during a long and boring NASA lecture. It careens wildly from intellectual to chaotic to Godel, Escher, Bach to Kurt Halsey to chaotic and sappy. The whole series is here . " "
"At the time xkcd was created, Randall was working on robotics at NASA 's Langley Center. This drawing was apparently made during that period, while attending a talk that he didn't like. The name of the comic is a portmanteau-like play on the following: The comic is drawn in the form of a storyboard and is clearly intended to be visualized as an animated sequence. In the first part of the comic, two people discuss the difficulty of comparing past and present generations, since the person making the comparison invariably belongs to one of the two groups. It's unclear whether the behatted guy is Black Hat , as Randall hadn't standardized his character designs yet, though the sarcastic comment suggests that it is. If it is, then this would be his first appearance. (He also appears in 12: Poisson , but that comic was released about 3 months later, but the numbering did not follow the release day on LiveJournal when the comics were transferred to xkcd - see the trivia for that comic.) Actually due to the order of release on LiveJournal, this, being number 6, was the first releases to use both stick figures, Cueball , Black Hat and Megan , as well as Multiple Cueballs ! See the trivia below. The assembly of text panels found in the middle of the strip is similar to 124: Blogofractal . The philosophy of Kurt Gödel is also a theme in 468: Fetishes . Drawn during an unending NASA lecture [Two people are talking, one in a hat.] Cueball: it's just so hard to compare kids now with kids in the past. you can't help but to belong to one group or the other. Cueball: and of course every generation seems awful to the one before it. look at quotes from throughout history. Hatted: yeah, and it sure would be nice to have some historical perspective on some of this stuff. I just don't know what to make of it. [Circles are appearing--maybe snow?] Cueball: i guess you do what you can to help the people around you and hope it turns out okay. Cueball: in the end, what else can you do? Hatted: lead a crusade? [We can no longer see the people, just the circles.] it's presentism, man. the idea that historical context is irrelevant, that we understand it all that we need take no warnings from the follies of the past. that we're facing something new. socrates couldn't imagine the internet. but people don't change. [We can start to see a darker circle in the lower right corner.] (The borders between the three panels on this line are cracking.) have you seen those collections of historical pornography? talk about historical context. did you know the first porn photo was bestial in. [inside a circle:] nature? at least that stuff was out of the mainstream [each word in one circle:] no just in history (the three panels have merged into one on each row.) i don't know about you, but [circled] I [uncircled] never even once seen [The circles are highly variable in size now, and pressed up against a larger one on the right side.] [There is mass of circles of different sizes, with some dark fissures in between, against the side of a large circle which we can see part of in the right half of the panel. They look like cells. There's a tiny square in the center of the giant cell.] [We see only the tiny square, centered. It has a few marks inside it.] [Closer, the square is divided into rectangles of different sizes, each of which has text in it.] [Much closer, we can see fragments of the text. Some are sideways, some are cut off, some are too small to read.] machine language translated by principles of isomorphism it is a consequence of the Church-Turing thesis that ... but how do you select the channel you wish to se- thou ... shou ... palin ... stri ... it is a ... crab ... be obvious to one-s ... your great intellectual achievements ... Tortise. Why ... you give this old Tortise ... [Closer still, we can just see a huge sideways s and h.] [Those letters are faded and mixed with a faded version of the next panel.] girls take boys away ... never be further than a phone call and a goosebumped shiver away ... drove all night listening to mix tapes ... the past is just practice [There is a heart at the bottom and, in the lower left, the name Kurt.] [The same as the previous panel, but with the words blurred out to scribbles.] [Jagged, shaded shapes and strands start to fall. Faint panel borders appear again. There is a person on the far right.] (Back to three panels per row.) [Cueball and Megan are standing amid the fragments.] Cueball: There's too much. And so little feels important. [The jagged edge of the shaded area is encroaching on the sides of the panel.] What do you do? [We see them from farther away through a rough hole in the shaded area. Bits continue to fall around them.] [They are holding hands.] "One of a series of strips I drew during a long and boring NASA lecture. It careens wildly from intellectual to chaotic to Godel, Escher, Bach to Kurt Halsey to chaotic and sappy. The whole series is here . " "
25
"Barrel - Part 4"
"Barrel - Part 4"
"https://www.xkcd.com/25"
"https://imgs.xkcd.com/comics/barrel_part_4.jpg"
"https://www.explainxkcd.com/wiki/index.php/25:_Barrel_-_Part_4"
"[The barrel is shown on a grid paper background, floating sideways and empty in a choppy sea.] Barrel series By the way, here are all the barrel comics on a single (easily linked) page: http://www.xkcd.com/barrel.html [This is an archived version of the page. The original link is dead. This text is not included in the statement.] I cheated, and went back and lightened the gridlines in #2. It was just bothering me. I'll try not to do that much. But as I'm not destroying anyone's childhood, I don't feel like I'm really pulling a George Lucas. I mean, I'm not destroying more than one childhood. Oops. "
"In the first three comics of the series, the character explored the ocean in a barrel and then encountered a whirlpool, all with a reaction of innocent wonder. Here, the empty barrel floating adrift, plus the title text and a previous announcement by Randall that this would be the conclusion of barrel boy's story, imply that the character's encounter with the whirlpool separated him from the barrel, and he may have come to some harm. This is the fifth in a six-part series of comics whose parts were randomly published during the first several dozen strips. The series features a character who is not consistent with what would quickly become the xkcd stick figure style. The character was in the barrel in parts 1-3. After Randall released the full The Boy and his Barrel story on xkcd, it has been clear that the original Ferret story should also be included as part of the barrel series. The full series can be found here . But below they are listed in the order Randall has put them in his collection linked to above: [The barrel is shown on a grid paper background, floating sideways and empty in a choppy sea.] Barrel series By the way, here are all the barrel comics on a single (easily linked) page: http://www.xkcd.com/barrel.html [This is an archived version of the page. The original link is dead. This text is not included in the statement.] I cheated, and went back and lightened the gridlines in #2. It was just bothering me. I'll try not to do that much. But as I'm not destroying anyone's childhood, I don't feel like I'm really pulling a George Lucas. I mean, I'm not destroying more than one childhood. Oops. "
26
"Fourier"
"Fourier"
"https://www.xkcd.com/26"
"https://imgs.xkcd.com/comics/fourier.jpg"
"https://www.explainxkcd.com/wiki/index.php/26:_Fourier"
"[Cueball talks on phone. A grotesque-looking cat with many sharp vertical points looks on.] Cueball: Hi, Dr. Elizabeth? Yeah, uh ... I accidentally took the Fourier transform of my cat... Cat: Meow! "
"A Fourier transform is a mathematical function transformation often used in physics and engineering. The theory is that any line graph can be represented as the sum of a bunch of sine waves of different frequencies and amplitudes. (The most obvious application is in analyzing a sound recording in terms of the different frequencies of sounds used.) So, for any line graph, you can produce another graph of the frequencies and their amplitudes. This can be done by evaluating an integral based on the function, which is referred to as "taking the Fourier transform" of the function. The form of the integral that needs to be taken is actually shown in the third line of the comic 55: Useless . Unfortunately, Cueball has applied this "transform" to his cat. Although it seems to still be alive and possibly even unharmed, it is clearly not in its familiar shape, and it is not clear if this condition is permanent or not. "Periodic components" in the title text refers to the spikes in the graph. Because sine waves repeat themselves as you go along, the presence of large amounts of one particular sine wave in the Fourier transform graph (each spike) shows that the overall result (the initial graph) is likely to have parts that also repeat themselves, like a periodic function . In other words, the cat has repeating parts. [Cueball talks on phone. A grotesque-looking cat with many sharp vertical points looks on.] Cueball: Hi, Dr. Elizabeth? Yeah, uh ... I accidentally took the Fourier transform of my cat... Cat: Meow! "
27
"Meat Cereals"
"Meat Cereals"
"https://www.xkcd.com/27"
"https://imgs.xkcd.com/comics/meat_cereals.jpg"
"https://www.explainxkcd.com/wiki/index.php/27:_Meat_Cereals"
"[A collection of fictional meat based cereals in bright colors with nice pictures on them.] Pork Loops Mice Krispies Hammios Frosted Bacon Flakes Scrapple Jacks Hey, these don't taste like Scrapple! Honey Bunches of Goats "
"Randall parodies several real-world breakfast cereals (which typically consist solely of grains and sweet flavorings) by creating versions that contain meat (animal products). The cereals that appear to be parodied (clockwise from top-left) include Froot Loops, Rice Krispies, Honey Bunches of Oats, Apple Jacks, Frosted Flakes, and Cheerios. There does not appear to be a deeper meaning to this comic than that. The Scrapple Jacks parody (the only slightly obscure reference) appears to be made with scrapple , which, according to Wikipedia, is a mush of pork scraps and trimmings combined with cornmeal and wheat flour, often buckwheat flour, and spices. Real Apple Jacks ran an ad campaign in the 1980s and 1990s in which an adult or authority figure tasted the cereal and declared "these don't taste like apples!", thus missing the point of why kids liked the cereal. The slogan is parodied on the Scrapple Jacks box. Randall referenced this same slogan again in " 38: Apple Jacks ". The title text, reading, "Disgusting.", apparently reflects Randall's opinion of his own creation. [A collection of fictional meat based cereals in bright colors with nice pictures on them.] Pork Loops Mice Krispies Hammios Frosted Bacon Flakes Scrapple Jacks Hey, these don't taste like Scrapple! Honey Bunches of Goats "
28
"Elefino"
"Elefino"
"https://www.xkcd.com/28"
"https://imgs.xkcd.com/comics/elefino.jpg"
"https://www.explainxkcd.com/wiki/index.php/28:_Elefino"
"Q: What do you get when you cross an Elephant with a Rhino? [Picture of elephant, mathematical addition symbol, picture of rhino, equals sign, large question mark.] A: I haven't a goddamn clue. Found it. Pepe and Seymour Elifino ... Totally worth the 🐇 hole. Iggynelix ( talk ) 15:45, 18 April 2020 (UTC) "
"The basis for this fairly simple xkcd comic is the subject riddle, which is properly answered, as given in the title text: "Hell if I know." When spoken, this "correct" answer sounds like "elephino" – a portmanteau of " eleph ant" and "rh ino ." This makes it again one of the early comics where Randall explains the comic via the title text. Instead of giving the punchline of the joke, Randall answers with the unexpected "I haven't a goddamn clue," which, while having the same meaning, ruins the joke. Q: What do you get when you cross an Elephant with a Rhino? [Picture of elephant, mathematical addition symbol, picture of rhino, equals sign, large question mark.] A: I haven't a goddamn clue. Found it. Pepe and Seymour Elifino ... Totally worth the 🐇 hole. Iggynelix ( talk ) 15:45, 18 April 2020 (UTC) "
29
"Hitler"
"Hitler"
"https://www.xkcd.com/29"
"https://imgs.xkcd.com/comics/hitler.jpg"
"https://www.explainxkcd.com/wiki/index.php/29:_Hitler"
"[Black Hat and Cueball are talking together in the same position in all four panels.] Cueball: Learning about the Holocaust has really shaken my belief in God. Black Hat: You know, as a young man, Hitler was rejected from art school. Cueball: Yeah... shame he didn't get in. Black Hat: Well, have you seen any of his paintings? They're awful . Defy all rules of composition. Cueball: What are you suggesting? Black Hat: Maybe there is a god, but he's a real art lover. Cueball: This is why I don't go out in public with you. "
"Cueball speaks to an early version of Black Hat (with more of a top hat than his later "boater" hat style) about the Holocaust and Adolf Hitler . Hitler was the leader of Nazi Germany beginning in 1933 and starting World War II in 1939 by attacking Poland. During that war, the Germans (under Hitler's leadership) killed millions of people; most of them were Jews, but other ethnic groups, homosexuals, and the mentally disabled were all targeted as well. This has come to be known as the Holocaust. Black Hat's comment that Hitler wanted to be a painter, but did not get into art school, is historically accurate. He applied to the Vienna Academy of Fine Arts twice. In any event, Cueball implies in the second frame that had Hitler been accepted into art school, the course of history might have changed, and the Holocaust might never have occurred. Black Hat suggests that perhaps God intentionally prevented Hitler from becoming an artist because God is an "art lover" and Hitler's art was terrible. As with other early comics, the title text explains the comic for us: this implies that God would have preferred the Holocaust to have occurred rather than allow Hitler to make some bad paintings. Such a comment that God could be so callous would surely be offensive to many people. Cueball's reaction to this shocking statement is relatively mild and suggests that Black Hat has made such controversial statements before. He will make a similarly controversial and Nazi-related statement again in 984: Space Launch System . The title text also informs the reader that Black Hat is based on a character named Aram from a now-defunct comic strip entitled Men in Hats . In the original quote when this comic was posted on LiveJournal (see Trivia ) Randall directed the user to a specific Men in Hats comic about parenting . Like Black Hat, Aram seems to have frequently made judgmental, insulting, or controversial comments in a very emotionless manner. Aram wore a grey (perhaps intended to be black) suit with a red bowtie and a black top hat with a white strip above the brim. Black Hat's hat clearly evolved from the top hat design later in xkcd. This may be the comic where Black Hat truly comes into existence for the first time. He appears earlier in 12: Poisson , but that was actually first released more than a month later. Then there is also 24: Godel, Escher, Kurt Halsey , released a good month earlier. But here Black Hat does not really resemble his later appearances. [Black Hat and Cueball are talking together in the same position in all four panels.] Cueball: Learning about the Holocaust has really shaken my belief in God. Black Hat: You know, as a young man, Hitler was rejected from art school. Cueball: Yeah... shame he didn't get in. Black Hat: Well, have you seen any of his paintings? They're awful . Defy all rules of composition. Cueball: What are you suggesting? Black Hat: Maybe there is a god, but he's a real art lover. Cueball: This is why I don't go out in public with you. "
30
"Donner"
"Donner"
"https://www.xkcd.com/30"
"https://imgs.xkcd.com/comics/donner.jpg"
"https://www.explainxkcd.com/wiki/index.php/30:_Donner"
"[Three people stand outside a restaurant; Megan, a man with some hair and another shorter person, probably a woman. There is a sign above the door which says "Joe's" (presumably the name of the restaurant) and a menu next to it. Outside the door, there is a maître d' with a cap behind a lectern. There is a sign on the lectern which says "Eat in".] maître d': Donner, party of four? Man: Actually, never mind. Megan: We're full. "
"The title text explains to the reader that the Donner party was a group of pioneers who set out west along a new route that was supposed to be easier to travel, but ultimately proved slow and treacherous. They became trapped in the Sierra Nevada mountains and many died. Low on food, many of the pioneers resorted to cannibalism, eating the bodies of party members who had already died, it is believed. In this comic, three Donner party members arrive at Joe's restaurant, where they have ordered a table for four, as given by the fact that the maître d' knows they are the Donner party and calls for a party of four. The three decline the table since they are already full. This suggests that they just have eaten the fourth member (unknown to us) of their party after they placed the order for a table at the restaurant, but before they strolled over to it anyway. Of course, since they are not in a survival situation in this strip, cannibalism would be completely unnecessary. However, it may be possible that they are suffering from Wendigo Psychosis . Alternatively, the Donner Dinner Party may have resorted to cannibalism because it took so long to be seated at the restaurant. In the early days of xkcd (and days when Wikipedia was not quite in the mainstream consciousness), Randall didn't trust people to understand his comics or his references, and often explained the joke in the title text like here and for instance also in 38: Apple Jacks . [Three people stand outside a restaurant; Megan, a man with some hair and another shorter person, probably a woman. There is a sign above the door which says "Joe's" (presumably the name of the restaurant) and a menu next to it. Outside the door, there is a maître d' with a cap behind a lectern. There is a sign on the lectern which says "Eat in".] maître d': Donner, party of four? Man: Actually, never mind. Megan: We're full. "
31
"Barrel - Part 5"
"Barrel - Part 5"
"https://www.xkcd.com/31"
"https://imgs.xkcd.com/comics/barrel_part_5.jpg"
"https://www.explainxkcd.com/wiki/index.php/31:_Barrel_-_Part_5"
"[A boy is grasping on to a piece of driftwood in an ocean.] [A zoomed out view of the boy still grasping on to a piece of driftwood in the ocean.] [A ferret with some airplane wings and an airplane tail flies above the ocean.] [A shot of the ocean, now empty.] [The flying ferret is carrying the boy to safety.] [The ferret carrying the boy is now in the distance with the sun on the horizon.] "
"This gives a happy ending to the Barrel series . The flying ferret is from 20: Ferret . The humor is derived from the juxtaposition of two unlike elements - in this case, the contemplative and even dark nature of the Barrel series being resolved through the timely intervention of a comical flying mammal. Said mammal could also be interpreted as a symbol of hope and following your dreams, seeing as in its original appearance, its powers of flight were just that: a dream. However, the dream becomes reality to save a child from an endless sea of hopelessness. The series is probably inspired by the novella The Little Prince by Antoine de Saint-Exupéry . Randall is well known to be a fan of this book. Somewhere between the release of the first ferret comic in October 2005 and the re-release of that comic (and all the other from LiveJournal in 2005) on New Year's Day 2006 on the new xkcd site, Randall's brother's ferret died - as given by the new RIP comment in the title text. The sad comment in the title text of 25: Barrel - Part 4 , ":(", possibly implying harm to the boy, along with this RIP comment, may imply that the boy has died and joined the ferret (in flying to Heaven). However, this line of reasoning only makes sense if the ferret actually died before the release of both the Part 4 comic at the end of October and this comic, which was released in the middle of November 2005, 1½ months before the new title text was made public. This is the last in a six-part series of comics whose parts were randomly published during the first several dozen strips. The series features a character who is not consistent with what would quickly become the xkcd stick figure style. The character was in a barrel in parts 1-3. After Randall released the full The Boy and his Barrel story on xkcd it has been clear that the original Ferret story should also be included as part of the barrel series. The full series can be found here . But below they are listed in the order Randall has put them in his collection, linked to above: [A boy is grasping on to a piece of driftwood in an ocean.] [A zoomed out view of the boy still grasping on to a piece of driftwood in the ocean.] [A ferret with some airplane wings and an airplane tail flies above the ocean.] [A shot of the ocean, now empty.] [The flying ferret is carrying the boy to safety.] [The ferret carrying the boy is now in the distance with the sun on the horizon.] "
32
"Pillar"
"Pillar"
"https://www.xkcd.com/32"
"https://imgs.xkcd.com/comics/pillar.jpg"
"https://www.explainxkcd.com/wiki/index.php/32:_Pillar"
"[At the top of the panel is a black frame with the following text:] This one is mostly by my little brother, Doug. [A Cueball-like guy stands on a the top of a tall pole and talks to his Cueball-like friend on the ground. The drawing is repeated three time in the same panel, once for each comment by the two guys.] Pole-guy: The sky is so blue, and all the leaves are green. Friend: Haven't you ever wondered if we really see the same colors as everyone else? It's all perception. Pole-guy: Well, you might as well call into question all of human experience. Who really knows what world someone else sees? Friend: Yeah, I guess. Pole-guy: Anyway, can you help me down from this pole? Friend: What pole? "Oops, I totally forgot to update yesterday afternoon. Well, I haven't slept, so I say it's still Friday. It's been a weird couple days and I was just thinking it was the weekend. Anyway, the first version of this strip was drawn by me and then written by Doug. I redrew/wrote it and now you are reading it! Cool, huh? Also, all the barrel strips are now here for easy linkage to people you think might like them." The link (now here above directing to a webarchive) used to direct to a collection of all six The Boy and his Barrel comics. It seems Randall had a long Friday back then. So long that he forgot to post this Friday comic before midnight. And although he still had not slept when he posted it, the time-stamp reads 7:55 AM on Saturday. This thus became the first comic to be released on a Saturday. This also happened to him the next Friday/Saturday. And then two times more before he closed LiveJournal. Since then it has not happened. "
"Two Cueball -like guys ponder the unanswerable philosophical question of whether all people observe the universe the same, or whether, for example, what one person sees as "red" might be what another see as "green". They muse that no one really knows how anyone else sees the world. The misdirection and punchline of the comic come when the pole-guy asks if his friend can help him down from this pole where he's been standing for the entire comic. The friend's reply indicates that he does not see a pole, proving that one person can observe the world differently than another, in this case, in a far more extreme and unexpected way than color differences. Another interpretation of the punchline is that the friend doesn't like pole-guy's idea of questioning all of human existence and mocks that philosophy by pretending not to see that he is standing on a pole. The concept of a philosopher on a pole is likely a reference to many " stylites " or "pillar-saints" of the late antiquity period, perhaps the first and most famous them being Simeon Stylites . Unlike most other xkcd comics, the "panels" of this comic are not divided and are drawn within a single frame. As noted at the title text, this comic is based on a comic drawn by Randall 's brother Doug, although Randall apparently redrew and rewrote it. [At the top of the panel is a black frame with the following text:] This one is mostly by my little brother, Doug. [A Cueball-like guy stands on a the top of a tall pole and talks to his Cueball-like friend on the ground. The drawing is repeated three time in the same panel, once for each comment by the two guys.] Pole-guy: The sky is so blue, and all the leaves are green. Friend: Haven't you ever wondered if we really see the same colors as everyone else? It's all perception. Pole-guy: Well, you might as well call into question all of human experience. Who really knows what world someone else sees? Friend: Yeah, I guess. Pole-guy: Anyway, can you help me down from this pole? Friend: What pole? "Oops, I totally forgot to update yesterday afternoon. Well, I haven't slept, so I say it's still Friday. It's been a weird couple days and I was just thinking it was the weekend. Anyway, the first version of this strip was drawn by me and then written by Doug. I redrew/wrote it and now you are reading it! Cool, huh? Also, all the barrel strips are now here for easy linkage to people you think might like them." The link (now here above directing to a webarchive) used to direct to a collection of all six The Boy and his Barrel comics. It seems Randall had a long Friday back then. So long that he forgot to post this Friday comic before midnight. And although he still had not slept when he posted it, the time-stamp reads 7:55 AM on Saturday. This thus became the first comic to be released on a Saturday. This also happened to him the next Friday/Saturday. And then two times more before he closed LiveJournal. Since then it has not happened. "
33
"Self-reference"
"Self-reference"
"https://www.xkcd.com/33"
"https://imgs.xkcd.com/comics/self-reference.jpg"
"https://www.explainxkcd.com/wiki/index.php/33:_Self-reference"
"[Cueball is standing alone.] Cueball: I promise to never again squeeze humor out of self-reference. [Beat panel.] [Cueball is standing alone.] Cueball: God dammit."
"Self-reference is a situation where something (a comic, a drawing, a musical work, a novel, a mathematical theorem) refers to itself in some manner. This can be a powerful technique in art, music, mathematics, and computer science (it is the basis of recursion). In this comic, Cueball promises not to use self-reference for humor, and then realizes after a beat panel that, since this comic is referring to the series of comics he is part of, he is using self-reference, thus breaking his promise. Without the last panel, this comic wouldn't be funny, and therefore wouldn't break the promise about using self-reference for humor. But with it, and his realization that he is breaking his promise, it does break that promise. (Do you get it?) The title text is just another humorous self-reference. Self-references has been used most famously later in 688: Self-Description , but was already used in 6: Irony and also in other comics . [Cueball is standing alone.] Cueball: I promise to never again squeeze humor out of self-reference. [Beat panel.] [Cueball is standing alone.] Cueball: God dammit."
34
"Flowers"
"Flowers"
"https://www.xkcd.com/34"
"https://imgs.xkcd.com/comics/flowers.jpg"
"https://www.explainxkcd.com/wiki/index.php/34:_Flowers"
"[A sketch of flowers, drawn in green, red, and yellow on a black background.] "Original drawing is pencil on graph paper . Bonus points if you can identify the flowers. 'cause I sure can't." "
"This is a drawing of flowers that Randall made. It seems the flowers are based on his imagination, rather than being a real species - see the original quote in the trivia section. The title text explains that Randall originally drew the flowers in pencil on normal paper; he did not paint them. Instead, he used the invert feature of a photo-editing program to reverse it from black-on-white to white-on-black. After that, he added color to the flowers. [A sketch of flowers, drawn in green, red, and yellow on a black background.] "Original drawing is pencil on graph paper . Bonus points if you can identify the flowers. 'cause I sure can't." "
35
"Sheep"
"Sheep"
"https://www.xkcd.com/35"
"https://imgs.xkcd.com/comics/sheep.jpg"
"https://www.explainxkcd.com/wiki/index.php/35:_Sheep"
"[Caption in a black frame above the image written in normal letters not all caps:] Another from my high-school notebooks. [A sheep and a green saguaro cactus in a brown pot are linked by an arcing yellow electricity bolt.] In the comment to the original LiveJournal post there was a user called Scott who posted this original poem: I had a little cactus and I treasured it with pride, admiring its spines and dainty flowers. Until the day - oh tragic day! - when it was RAMIFIED, by a ram with strange psychokinetic powers. Baaing deep, this shaman sheep came whiffling through the brambles. It gazed upon my cactus and, with yellow flash and thudrous crash, with dashing, brash, and rash panache, it blew the plant to shambles. I was, I confess, horrified - I sat and cried my eyes out! Oh stupid sheep, satanic sheep, so wrong and rash and willful! I nursed the cactus best I could, till finally it came about. It grows apace now, once again, but all it blooms is steel wool! [And then in another post beneath this posted four minutes after the poem at 4:57 UTC (AM?) he finished with:] Oh God I need sleep! If this is the Scott who is a friend of Randall, it is not entirely clear.... Mary had a little lamb She tied it to a pylon Ten thousand volt went up its a** And turned its wool to nylon. "
"Due to Randall's vacation, he picked out comics from his old high-school notebooks. This is the second in a row. It was also released a day too late. It is a very weird drawing, especially with the title text proclaiming that it may be the sheep that is zapping the cactus. The comic 520: Cuttlefish may be a reference to this comic. It may also be a Pokémon reference, with the sheep being the Electric-type Mareep or its evolution Flaaffy, and the cactus being Cacnea or Cacturne. [Caption in a black frame above the image written in normal letters not all caps:] Another from my high-school notebooks. [A sheep and a green saguaro cactus in a brown pot are linked by an arcing yellow electricity bolt.] In the comment to the original LiveJournal post there was a user called Scott who posted this original poem: I had a little cactus and I treasured it with pride, admiring its spines and dainty flowers. Until the day - oh tragic day! - when it was RAMIFIED, by a ram with strange psychokinetic powers. Baaing deep, this shaman sheep came whiffling through the brambles. It gazed upon my cactus and, with yellow flash and thudrous crash, with dashing, brash, and rash panache, it blew the plant to shambles. I was, I confess, horrified - I sat and cried my eyes out! Oh stupid sheep, satanic sheep, so wrong and rash and willful! I nursed the cactus best I could, till finally it came about. It grows apace now, once again, but all it blooms is steel wool! [And then in another post beneath this posted four minutes after the poem at 4:57 UTC (AM?) he finished with:] Oh God I need sleep! If this is the Scott who is a friend of Randall, it is not entirely clear.... Mary had a little lamb She tied it to a pylon Ten thousand volt went up its a** And turned its wool to nylon. "
36
"Scientists"
"Scientists"
"https://www.xkcd.com/36"
"https://imgs.xkcd.com/comics/scientists.jpg"
"https://www.explainxkcd.com/wiki/index.php/36:_Scientists"
"[Cueball is staring at an empty box on the floor.] Cueball: In what scientists are calling "pretty gay", I can't find my shoes. "
"This comic plays on the type of statement that news reports often use: "in what [group of experts] are calling '[quote]'," to add more weight and credibility to their stories. In this case, Cueball is using the phrase to attempt to add gravitas to the (relatively mundane) fact that his shoes are missing and he thinks it's "pretty gay" by assigning this opinion to scientists (rather than it being, presumably, his friend's or his own opinion). The same joke is at play in the image text where a leading expert thinks the situation is "retarded." There may be a second level to the joke: Randall was still working for NASA at the time the comic was posted, so his friends at that time would presumably include scientists and "leading experts." If his friends made fun of him for not being able to find his shoes, it would therefore be accurate to say that scientists had made those statements. However, since their being scientists is irrelevant to the legitimacy of their opinions about Randall's shoe problems, presenting their teasing as an expert opinion is humorously misleading; a similar joke is at play in 1206: Einstein . The phrases "pretty gay" and "retarded" are infantile and offensive slang for "foolish" or "contemptible," and so they are the opposite type of speech expected of experts on news reports. (These terms were not generally considered more than mildly offensive by most of the public at the time this comic was posted; the cultural mainstream is now typically much more critical of this type of language, and this comic would likely be heavily criticized if it were published today.) [Cueball is staring at an empty box on the floor.] Cueball: In what scientists are calling "pretty gay", I can't find my shoes. "
37
"Hyphen"
"Hyphen"
"https://www.xkcd.com/37"
"https://imgs.xkcd.com/comics/hyphen.jpg"
"https://www.explainxkcd.com/wiki/index.php/37:_Hyphen"
"[Cueball (on the left) is talking to his Cueball-like friend (on the right) about a car (left to both of them) that resembles a Volkswagen Beetle. Above the drawing is a statement:] My hobby: whenever anyone calls something an [adjective]-ass [noun], I mentally move the hyphen one word to the right. Cueball: Man, that's a sweet ass-car. "
"This is the first " My Hobby " comic in xkcd . In these comics, Randall suggests an obscure activity or pastime he enjoys that he declares as his "hobby." In the premiere "My Hobby" comic, Randall's hobby is mentally re-interpreting what people mean when they say "[adjective]-ass [noun]" by moving the hyphen to after the word "ass" instead of before. The semi- scatological suffix "-ass" is used as an intensifier in informal US English speech, usually attached to an adjective directly modifying a noun, as in "big-ass car" or "funny-ass comedian." In this comic, Cueball is exploring the increased humor aspect of changing "-ass" from a suffix modifying the adjective, to "ass-", a prefix modifying the noun, yielding a "big ass-car" or a "funny ass-comedian," the former presumably being a large car for carrying buttocks, the latter being a humorous comedian specializing in jokes about lower backs. The prefix "ass-" may also have a negative connotation, indicating that something is disliked. An "ass-car" may be a very terrible car, for example. Another explanation would be that, since this suffix/prefix refers to an element of human anatomy, the car would be in the shape of said anatomical piece. Outside of North America, most English speakers use "arse" to mean the buttocks, so to them, it may sound as if Randall's talking about donkeys. [Cueball (on the left) is talking to his Cueball-like friend (on the right) about a car (left to both of them) that resembles a Volkswagen Beetle. Above the drawing is a statement:] My hobby: whenever anyone calls something an [adjective]-ass [noun], I mentally move the hyphen one word to the right. Cueball: Man, that's a sweet ass-car. "
38
"Apple Jacks"
"Apple Jacks"
"https://www.xkcd.com/38"
"https://imgs.xkcd.com/comics/apple_jacks.jpg"
"https://www.explainxkcd.com/wiki/index.php/38:_Apple_Jacks"
"[Cueball is standing holding a bowl in his hand. His son is sitting on the floor playing video games.] Cueball: Hey, these don't taste like apples! Son: Fuck off, Dad. "
"Apple Jacks is a breakfast cereal produced by Kellogg's . As the title text begins to explain, there was an ad campaign for the cereal in the 1990s that focused on someone (usually someone in authority like a parent) pointing out that Apple Jacks doesn't taste like apples, and one or more kids pointing out that it doesn't matter and that "we eat what we like." However, instead of laughing off his dad's comment and correcting him, as in the campaign, this son responds by simply saying "fuck off, dad." This could be a commentary on today's youth being far less respectful, as the son is playing video games and seems annoyed at being interrupted, though this does not align with Randall’s public views. It may not be the first time the father has used the line, and the son is irritated by the repetition. It could also be saying that the response in the ads is unrealistic, and this is a much more realistic response. The same ad campaign was referenced previously in 27: Meat Cereals on a parody cereal labeled Scrapple Jacks. Cereal advertising was again referenced in 1470: Kix . The title text could be a reference to the fact that this comic requires explanation for those who don't know of the ad (the reason this webpage exists), or it is an addition to the joke. This is another of the early comics where Randall felt the need to explain the joke in the title text, see for instance 30: Donner . [Cueball is standing holding a bowl in his hand. His son is sitting on the floor playing video games.] Cueball: Hey, these don't taste like apples! Son: Fuck off, Dad. "
39
"Bowl"
"Bowl"
"https://www.xkcd.com/39"
"https://imgs.xkcd.com/comics/bowl.jpg"
"https://www.explainxkcd.com/wiki/index.php/39:_Bowl"
"[A boy is glaring at a model sailing ship floating in a bowl of water.] Boy: Sooner or later, my friend, one of us will run out of time. "This is not the barrel boy. Current Mood: Final Exam-y " Announcement "What with winter break starting and the like, I'll probably be going off my regular update schedule. I'll try to post something here and there, and might end up doing more drawings than I expect, but won't stick to the MWF schedule. Thanks for the support! This has been and will continue to be a lot of fun." This may also be due to his examinations coming up. But probably he was using a lot of time preparing for the release of his new xkcd site after new year. "
"The comic roughly parodies a situation in which two characters are seeing who can wait longer to get the result they want. However, in the comic, the model sailing ship is not alive and doesn't experience time (except perhaps if it absorbs water and falls apart, or beaches once the water in the bowl evaporates). The comic compares the patience of a boy with that of an inanimate object. Also, it could imply that the boy has too much time on his hands. Like many of the earlier comics, some of this comic's humor comes from the surreality of the situation. The gravity of the boy's statement is juxtaposed with the insignificance of a child's toy floating in a bowl of water. On one level, the absurdity of this is funny in itself; on another level, the audience is invited to imagine what might possibly be going through the boy's mind to make him take this toy and bowl so seriously. Alternatively, the comic can be taken to recognize the mortality and ultimate fate of death/decay for both the boat and the boy, creating a grim moral. But, if one goes deeper into meaning, one could realize that the comic itself is humorous for trying to make a fatalistic statement using a boy and a toy boat, still making the comic ultimately humorous. In the original quote for this comic (see trivia ), Randall states that this is not the barrel boy . This is not only because they have a similar hairstyle. Since the Barrel Boy was floating on the water in a barrel, and this boy is looking into a bowl (not barrel) filled with water, it would be easy to draw some parallels. It was obviously important for Randall to make clear that there were no such connections. [A boy is glaring at a model sailing ship floating in a bowl of water.] Boy: Sooner or later, my friend, one of us will run out of time. "This is not the barrel boy. Current Mood: Final Exam-y " Announcement "What with winter break starting and the like, I'll probably be going off my regular update schedule. I'll try to post something here and there, and might end up doing more drawings than I expect, but won't stick to the MWF schedule. Thanks for the support! This has been and will continue to be a lot of fun." This may also be due to his examinations coming up. But probably he was using a lot of time preparing for the release of his new xkcd site after new year. "
40
"Light"
"Light"
"https://www.xkcd.com/40"
"https://imgs.xkcd.com/comics/light.jpg"
"https://www.explainxkcd.com/wiki/index.php/40:_Light"
"[A crowd of figures stand around in the dark. A Megan is illuminated by a beam of light.] In a dark and confusing world, you burn brightly I never feel lost "
"Lighthouses were built on coasts to give ships a point of reference where land was, so that they could find where they were going, and to know where they should avoid during a storm. Megan fills this role for Cueball . She is his lighthouse to know where he can be safe. This also has a romantic notion, as Megan is lighting up the world for Cueball to find her. [A crowd of figures stand around in the dark. A Megan is illuminated by a beam of light.] In a dark and confusing world, you burn brightly I never feel lost "
41
"Old Drawing"
"Old Drawing"
"https://www.xkcd.com/41"
"https://imgs.xkcd.com/comics/unspeakable_pun.jpg"
"https://www.explainxkcd.com/wiki/index.php/41:_Old_Drawing"
"[A tree holding a chainsaw over a recently cut-down tree. The first text is in a frame at the top of the panel.] I found this in one of my high-school notebooks. I think I drew it just to take revenge on people snooping through my stuff. Tree stump: Well, you stumped me... "
"This comic plays off the pun between stumped , meaning confused or at a loss, and a stump , which is the remnants of a tree that has been cut down. Anyone snooping into his journal would be punished by such a terrible pun. The pun is so terrible that even Randall does not want to talk about it, as he mentioned in the title text. [A tree holding a chainsaw over a recently cut-down tree. The first text is in a frame at the top of the panel.] I found this in one of my high-school notebooks. I think I drew it just to take revenge on people snooping through my stuff. Tree stump: Well, you stumped me... "
42
"Geico"
"Geico"
"https://www.xkcd.com/42"
"https://imgs.xkcd.com/comics/geico.jpg"
"https://www.explainxkcd.com/wiki/index.php/42:_Geico"
"[Cueball holding a golf club.] Cueball: I just saved a bunch of money on my car insurance by threatening my agent with a golf club. "
"This comic references a long-running ad campaign for Geico insurance in which a character (different in each commercial) lists a series of horrible events or news, but then caps it off with "but I've got good news: I just saved a bunch of money on my car insurance by switching to Geico" – news that may be good, but is usually either trivial compared to the magnitude of the preceding bad news, or else is said to the person whom all of the preceding bad news applied to, giving them false hope that the good news was for them. It became a recognizable pop culture phrase. Geico's ad is also mentioned in 870: Advertising . In this one-panel comic, Cueball parodies the punchline by saving money on his car insurance by intimidation, instead of choosing the best provider. In the title text, Randall attributes this comic to the unknown friend David . He does the same in 51: Malaria and 100: Family Circus . We can assume (or rather, we can hope ) that "this" refers to the act of writing the comic, as opposed to the act of threatening his insurance agent. A golf club is also mentioned, and used for similarly socially unacceptable actions, in 81: Attention, shopper . [Cueball holding a golf club.] Cueball: I just saved a bunch of money on my car insurance by threatening my agent with a golf club. "
43
"Red Spiders 2"
"Red Spiders 2"
"https://www.xkcd.com/43"
"https://imgs.xkcd.com/comics/red_spiders_2.jpg"
"https://www.explainxkcd.com/wiki/index.php/43:_Red_Spiders_2"
"[Nine red spiders, with round appendages at the end of each of their six legs, are seen navigating an environment of blocks and other geometric constructions. The second-from-the-top spider appears to be holding a block down for the spider just below to climb on to help it up, or they might be lifting the block together. One is almost outside the frame at the top.] "
"This is the second published comic in the red spiders story arc, published just over 2 months after the first one . Like its predecessor, it is more of a sketch than a comic. The titular spiders appear to be ascending —or possibly building— a structure, probably to get into the window at the top of the picture. Two spiders at the top appear to be passing a block between them, implying that they are, at least, trying to change the structure. According to the title text, it was drawn years before the previous Red Spiders . The full series of Red Spiders comics: [Nine red spiders, with round appendages at the end of each of their six legs, are seen navigating an environment of blocks and other geometric constructions. The second-from-the-top spider appears to be holding a block down for the spider just below to climb on to help it up, or they might be lifting the block together. One is almost outside the frame at the top.] "
44
"Love"
"Love"
"https://www.xkcd.com/44"
"https://imgs.xkcd.com/comics/love.jpg"
"https://www.explainxkcd.com/wiki/index.php/44:_Love"
"[Cueball and Megan stand facing one another.] Cueball: I love you! Megan: I love you! [Same scene as before.] Cueball: I love you more! Megan: Yeah. [Beat panel.] "
"This comic expresses the view of a love that is unbalanced and unequal. And how one form of love can be painful when closely examined. It is customary for people in a romantic relationship, when one makes a declaration of love or affection, for the other to make a matching declaration. However, instead of continuing Cueball 's escalation by saying the expected response "I love you more!", Megan stops and agrees with him: he does love her more than she loves him. This leads to an uncomfortable dynamic in the relationship. The final frame shows the couple standing in silence. In the title text, Randall expresses how this comic is shockingly stark in its portrayal of love. [Cueball and Megan stand facing one another.] Cueball: I love you! Megan: I love you! [Same scene as before.] Cueball: I love you more! Megan: Yeah. [Beat panel.] "
45
"Schrodinger"
"Schrodinger"
"https://www.xkcd.com/45"
"https://imgs.xkcd.com/comics/schrodinger.jpg"
"https://www.explainxkcd.com/wiki/index.php/45:_Schrodinger"
"[Black Hat and Cueball are standing next to each other. Above them the text is written in a box with shades around it.] Schrödinger's Comic [Black Hat and Cueball are still standing next to each other, but Cueball has lifted his arms above his head. The text is again written in a box with shades around it.] The last panel of this comic is both funny and not funny at the same time. [Black Hat and Cueball are still standing next to each other, Cueball arms are down again. The text is again written in a box with shades around it.] Until you read it, there's no way to tell which it will end up being. [Black Hat and Cueball are still standing next to each other. Cueball has become smaller and smaller through the three frames after the first. Quite clearly here in the last panel. The text is again written in a box with shades around it.] Shit. "
"This comic is a joke creating a humorously false synthesis, combining the principles of quantum superposition and the effects of reading a comic one panel at a time. Schrödinger's cat is a thought experiment that illuminates the notion that a particle only resolves itself to its state upon observation, and until such observation is made, it is in all of its possible states simultaneously. In the thought experiment, a cat is both dead and alive until observation; likewise, in this comic, Black Hat and Cueball are likening the last panel to the box with the cat: until you read it, it is in a mixed state (a superposition) of both funny and unfunny. Finally, in the last panel, both of them say "Shit." The joke is that after reading the last panel, the comic is both funny (as it is unexpected) and not funny (as the last line was a non sequitur and therefore there is no climax) at the same time, thus proving Black Hat and Cueball wrong, hence them expressing discontent with the word "shit." The title text , which Randall here calls the alt-text, suggests that the alt text did not exist until the mouse over action occurred. This is another reference to Schrödinger's cat. You do not know if there is a title text until you mouse over, so before you mouse over, the title text could be missing or existent. Schrödinger's cat is a famous thought experiment proposed by Erwin Schrödinger to question the Copenhagen interpretation of quantum mechanics. Under the Copenhagen interpretation , any particle is described by a wave function that allows one to calculate the probability that it is any given state. A radioactive nucleus with a half-life of one hour, for instance, would have a wave-function that would split, showing two distinct states (decayed, undecayed) that change over time until some "observation" forced the wave-function into one state or another (called "collapsing the wave-function"). Before the wave-function is collapsed, it is incorrect to say that the atom has decayed or has not decayed; it is in a "superposition" of states, effectively both decayed and undecayed. Schrödinger thought that the Copenhagen interpretation was absurd, and devised the below thought experiment to show this. The experiment goes as follows: Put a cat in a box, he said, with a device triggered by the decay of an atom with a half-life of one hour that would release a poisonous gas if triggered. Then, after waiting an hour, the Copenhagen interpretation would say that the atom is in a superposition of decayed and undecayed states, and thus, by extension, the cat would be in a superposition of alive and dead states. Only when the box is opened would the wave-function for the cat collapse into either alive or dead states. This thought experiment is not meant to be taken literally, as every interaction of a particle with another constitutes an observation, and many particles must interact for a cat to die, but still his argument was that since it is absurd for a cat to be both alive and dead, it is absurd for an atom to be both decayed and undecayed. If this experiment were to be performed, the cat would not be both dead and alive. [Black Hat and Cueball are standing next to each other. Above them the text is written in a box with shades around it.] Schrödinger's Comic [Black Hat and Cueball are still standing next to each other, but Cueball has lifted his arms above his head. The text is again written in a box with shades around it.] The last panel of this comic is both funny and not funny at the same time. [Black Hat and Cueball are still standing next to each other, Cueball arms are down again. The text is again written in a box with shades around it.] Until you read it, there's no way to tell which it will end up being. [Black Hat and Cueball are still standing next to each other. Cueball has become smaller and smaller through the three frames after the first. Quite clearly here in the last panel. The text is again written in a box with shades around it.] Shit. "
46
"Secrets"
"Secrets"
"https://www.xkcd.com/46"
"https://imgs.xkcd.com/comics/secrets.jpg"
"https://www.explainxkcd.com/wiki/index.php/46:_Secrets"
"[Drawing of a lonely girl staring down with almost closed eyes. The first line of text stands next to her to the left. The last part bottom, right.] I just want you to share in my secrets and not run away Kurt Halsey was also referenced in 24: Godel, Escher, Kurt Halsey . "
"This comic addresses the issue of commitment-phobic partners who get into relationships but get cold feet when it starts to get serious. The girl wants someone who can see every part of who she is and still love her. In the title text, Randall mentions that he is a big fan of Kurt Halsey , a comic artist from Oregon. His style is similar to that in this comic. Many of his comics and paintings depict a couple and convey various emotions they go through, as does this comic. In the original Randall quote (see trivia ), he gives the above link to the official home page of Kurt Halsey. Then he mentions that if you had not realized he was a big fan already, you should reconsider clicking on the link because it's depressing how much better at this he is than me . [Drawing of a lonely girl staring down with almost closed eyes. The first line of text stands next to her to the left. The last part bottom, right.] I just want you to share in my secrets and not run away Kurt Halsey was also referenced in 24: Godel, Escher, Kurt Halsey . "
47
"Counter-Red Spiders"
"Counter-Red Spiders"
"https://www.xkcd.com/47"
"https://imgs.xkcd.com/comics/counter-red-spiders.jpg"
"https://www.explainxkcd.com/wiki/index.php/47:_Counter-Red_Spiders"
"[A stack of stick figures, standing on each others shoulders, extends from the bottom of the frame to the top. Cuboids hang in the air.] The counter-red-spider offensive begins... "
"In previous comics, red spiders are seen navigating similar landscapes. Here, humanoid stick figures are standing on top of each other to reach some place above the top of the comic, in a similar manner to how the red spiders navigate. These stick figures must be extremely light, or gravity must be really weak there, because it is extremely unlikely or even impossible to have a stack of humans that tall. The full series of Red Spiders comics: [A stack of stick figures, standing on each others shoulders, extends from the bottom of the frame to the top. Cuboids hang in the air.] The counter-red-spider offensive begins... "
48
"Found"
"Found"
"https://www.xkcd.com/48"
"https://imgs.xkcd.com/comics/found.jpg"
"https://www.explainxkcd.com/wiki/index.php/48:_Found"
"[Cueball and Megan are standing on a white hill (presumably snow) with a grey sky covered with thick streaks of white, and small pink dots. All letters are written in lower case.] we are just two people who found each other "
"Cueball and Megan are standing together in the middle of a simple maze. As indicated by the words in the comic, they have simply found each other, implying that there is no relationship between them other than running into each other. As indicated in the title text, there is nothing else to say about how they met. [Cueball and Megan are standing on a white hill (presumably snow) with a grey sky covered with thick streaks of white, and small pink dots. All letters are written in lower case.] we are just two people who found each other "
49
"Want"
"Want"
"https://www.xkcd.com/49"
"https://imgs.xkcd.com/comics/want.jpg"
"https://www.explainxkcd.com/wiki/index.php/49:_Want"
"[Cueball is standing talking in the same position in all four panels. In the second panel, Cueball seems to have hair.] Cueball: I want to be brave enough to tell you how I feel. Cueball: I want to say "I love you" before I hang up the phone for once. Cueball: I want to drive all night with you, listening to mix tapes, not caring where we end up. Cueball: Oh, and I also really want to get with your sister. Cueball: I mean, DAMN. "
"Cueball is making an honest profession of his feelings. This is often held up as a valuable thing in cementing a relationship. In the first three panels, he makes the kind of cliched poetic, romantic statements that would typically be expected. In the last panel, however, he undercuts all of this by crassly revealing that he also really wants to have sex with his paramour's sister. In the title text, he attempts to excuse his statement by reasoning that the sister is very attractive. [Cueball is standing talking in the same position in all four panels. In the second panel, Cueball seems to have hair.] Cueball: I want to be brave enough to tell you how I feel. Cueball: I want to say "I love you" before I hang up the phone for once. Cueball: I want to drive all night with you, listening to mix tapes, not caring where we end up. Cueball: Oh, and I also really want to get with your sister. Cueball: I mean, DAMN. "
50
"https://www.xkcd.com/50"
"[A color drawing of Tycho, a man with wild brown hair in blue and cyan colored shirt. He has a big open mouth and holds one arm up while the other may be in his (unseen) pocket. He has two speech bubbles,] Tycho: You know what? If you've never played the 1995 SNES RPG " Seiken Densetsu ", don't even bother reading today's strip. Tycho: We don't need your kind here. "
"Penny Arcade is a popular web comic that focuses on video game culture. The character above is Tycho Brahe, one of the two main characters of Penny Arcade (the other being Jonathan "Gabe" Gabriel). Penny Arcade has a reputation for making obscure references to video games without explaining, expecting the reader to be as well-versed in gaming culture as they are, represented by the attitude shown in this comic. 'Seiken Densetsu,' as mentioned in the strip, probably refers to Seiken Densetsu 3 , an Action role-playing game (Action-RPG) released for the Super Nintendo Entertainment System (SNES) in Japan in 1995. The game was neither released in the North American region nor officially translated to English for more than thirteen years after this strip. However, many North American game players might have recognized Seiken Densetsu 2 , the predecessor in the series, by its North American name: Secret of Mana . As the title text admits, they know they behave like this, and have this reputation, but they don't care, and even refer to it in their own comic. [A color drawing of Tycho, a man with wild brown hair in blue and cyan colored shirt. He has a big open mouth and holds one arm up while the other may be in his (unseen) pocket. He has two speech bubbles,] Tycho: You know what? If you've never played the 1995 SNES RPG " Seiken Densetsu ", don't even bother reading today's strip. Tycho: We don't need your kind here. "
51
"Malaria"
"Malaria"
"https://www.xkcd.com/51"
"https://imgs.xkcd.com/comics/malaria.jpg"
"https://www.explainxkcd.com/wiki/index.php/51:_Malaria"
"[Four Cueball-like children wearing party hats, a discarded balloon is lying to the right. There is text above:] We had a malaria party [And there is text below:] but it turned out not to be very much fun. "
"This comic humorously considers pox parties as a means of preventing malaria. In these "parties," adults bring their children to deliberately expose them to a communicable disease to promote immunity . This is commonly done for a childhood disease like chickenpox and measles instead of vaccination. In this comic, we see four Cueball -like children in party hats with a balloon lying on the ground, suggesting a missing "celebrant." Some illnesses are more serious for adults than children. For example, chickenpox is far less severe contracted as a child than as an adult, the latter sometimes ending in sterility, brain damage, or worse. (Note that shingles is not adult-onset chickenpox, but a condition occasionally developed by older people who previously had chickenpox.) Having caught chickenpox once, a person's immune system has developed antibodies , reducing vulnerability to the virus. The antibodies create immunity for a significant period of time, possibly life. However, immunity through antibody creation is not usually an effective strategy against malaria. Contrarily, once one has suffered from malaria, it can recur on its own, even after apparent healing from symptoms. Thus, having a malaria party would not be a useful exercise, as many could suffer significant illness and die. The title text blames "David" for the party, referencing the idea of children blaming each other for an idea that turns out poorly. A malaria party is likely to have more severe consequences than, for instance, a group of 10 year olds building a ski ramp in the backyard. Also it could be a reference to the Bible: when King David has to choose between three Threads, he chooses a disease for the whole people, lasting 3 days. Malaria is a Mosquito-borne disease of humans and other animals caused by protists (a type of microorganism) of the genus Plasmodium . It begins with a bite from an infected female mosquito , which introduces the protists via its saliva into the circulatory system, and ultimately to the liver where they mature and reproduce. The disease causes symptoms that typically include fever and headache, which in severe cases can progress to coma or death. At the end of the 1990s, a study reported what would turn out to be made-up health threats from MMR- vaccines , which created an MMR vaccine controversy and lower vaccination rates, even after they were exposed as false. This made pox parties more popular as the "natural alternative." However, even usually-"harmless" diseases like measles can (rarely) have complications and side-effects, up to and including death, which are by far more common and/or more severe than the actual health risks involved in vaccination. In the past 20 years, 2 Americans died from measles, both people with compromised immune systems. Also none, or late immunization, may create an immunization gap through which nearly extinct diseases can reenter a population (see e.g. Epidemiology of measles ). If this gap can be closed (or made small enough), it is possible to make a disease extinct. This was actually successfully done with smallpox , and is now attempted with the poliovirus (Causing poliomyelitis , also known as infantile paralysis). [Four Cueball-like children wearing party hats, a discarded balloon is lying to the right. There is text above:] We had a malaria party [And there is text below:] but it turned out not to be very much fun. "
52
"Secret Worlds"
"Secret Worlds"
"https://www.xkcd.com/52"
"https://imgs.xkcd.com/comics/secret_worlds.jpg"
"https://www.explainxkcd.com/wiki/index.php/52:_Secret_Worlds"
"[A multitude of circles connected with several lines. Most of them are rather small and colored red, yellow, green and blue. Nine of them are white, six of these are larger than all the other circles, but one is the same size as the largest colored (green) circle, and the two smallest are smaller than a few of the colored circles. Pieces of text are written in all the white circles. Although it can be confusing at first, the reading order is still the normal one: left to right and top to bottom. Reading the circles in that order gives the following text:] "Everybody has a secret world inside of them. All of the people in the whole world I mean everybody No matter how dull and boring they are on the outside Inside they've all got unimaginable magnificent, wonderful, stupid, amazing, worlds Not just one world. Hundreds of them. Thousands, maybe." --Neil Gaiman Sandman "
"The quote written in the large white bubbles comes from The Sandman , a comic book series about dreams. Neil Gaiman is a science fiction and fantasy author who came to fame for writing The Sandman. The interconnected bubbles represent the secret worlds of different people and how they are connected. They may have the second meaning of the neurons in our brain. The title text indicates that Randall used the Four color theorem , which states that a graph drawn on a flat plane (like this one) requires at most four colors so that each region differs from all of its neighbors. The comic uses four colors (red, yellow, green, blue). This clearly does not include the white bubbles with text. Here is the quote, to those wondering how to read the comic: “Everybody has a secret world inside of them... All of the people in the whole world, I mean everybody — no matter how dull and boring they are on the outside. Inside them they've all got unimaginable, magnificent, wonderful, stupid, amazing worlds... Not just one world. Hundreds of them. Thousands, maybe.” Neil Gaiman, A Game of You [A multitude of circles connected with several lines. Most of them are rather small and colored red, yellow, green and blue. Nine of them are white, six of these are larger than all the other circles, but one is the same size as the largest colored (green) circle, and the two smallest are smaller than a few of the colored circles. Pieces of text are written in all the white circles. Although it can be confusing at first, the reading order is still the normal one: left to right and top to bottom. Reading the circles in that order gives the following text:] "Everybody has a secret world inside of them. All of the people in the whole world I mean everybody No matter how dull and boring they are on the outside Inside they've all got unimaginable magnificent, wonderful, stupid, amazing, worlds Not just one world. Hundreds of them. Thousands, maybe." --Neil Gaiman Sandman "
53
"Hobby"
"Hobby"
"https://www.xkcd.com/53"
"https://imgs.xkcd.com/comics/hobby.jpg"
"https://www.explainxkcd.com/wiki/index.php/53:_Hobby"
"[A person with hair lies on the ground in a pool of red blood. At the top of the panel there is a caption. Then a text. And above the person there is a score with small lines around to indicate that it has just appeared over the body.] My hobby: When the police bust drug hideouts, I sneak in and hide. Then I jump out and startle them into shooting me so they lose points. -100 "I'm reminded of Area 51 where you accidently kept shooting the cops in the back...over and over again. Brilliant." Randall made the following reply: "That was actually precisely the game I was thinking of. I remember my brother playing that game all day at the arcade when we were little. Fuckin' innocents." This comment is reflected in the title text on xkcd. "
"This is the second in the " My Hobby " series of xkcd comics. This comic humorously compares the rules of light gun cabinet arcade video games with real life. Randall suggests that his hobby is going to drug busts with the expressed purpose of getting shot as an innocent bystander, thereby causing the police to lose 100 points. Drug busts are events where police attempt to catch drug dealers, suppliers, and financiers in situations with enough evidence to convict them. In the style of arcade video games being examined, drug busts are usually depicted as chaotic events with villains, innocent bystanders, captives, and allies popping up like spring loaded targets at a shooting range in a setting with lots of places to hide. If you don't shoot a hostile target sufficiently quickly, you will be shot, so it is common to shoot the wrong targets. To add extra challenge, these games often deduct points — or worse, cause damage to the player character — if the player shoots the wrong target. This is often frustrating; not only does the player feel that they have failed to judge their target properly, but the wasted time can cause them to get shot by the real targets. Obviously, doing this in real life would be a really bad idea, as the hobbyist would quickly be killed. Whether this can even be a hobby is questionable because hobbies typically refer to actions that one does repeatedly, but if one was killed the first time, one would not be able to sneak into drug busts and startle police officers again. Also, if Randall actually did this, he would be dead and therefore unable to draw a comic about it. [ citation needed ] The title text refers to the game Area 51 , which was a popular shooter arcade game from 1995 (although a console/PC game of the same name was released in 2005). Area 51 was one of many cabinet arcade games that featured a light gun that allowed players to aim at the screen and shoot in a realistic control mechanic. The title text confirms that the comic is referring to these light gun cabinet games specifically. The title text of 188: Reload references this strip. [A person with hair lies on the ground in a pool of red blood. At the top of the panel there is a caption. Then a text. And above the person there is a score with small lines around to indicate that it has just appeared over the body.] My hobby: When the police bust drug hideouts, I sneak in and hide. Then I jump out and startle them into shooting me so they lose points. -100 "I'm reminded of Area 51 where you accidently kept shooting the cops in the back...over and over again. Brilliant." Randall made the following reply: "That was actually precisely the game I was thinking of. I remember my brother playing that game all day at the arcade when we were little. Fuckin' innocents." This comment is reflected in the title text on xkcd. "
54
"Science"
"Science"
"https://www.xkcd.com/54"
"https://imgs.xkcd.com/comics/science.jpg"
"https://www.explainxkcd.com/wiki/index.php/54:_Science"
"[A graph with a curve that begins at zero, then peaks at a given frequency, indicated via a thin vertical line, and then fades down towards zero. It is possible to see the data points, which fit the curve perfectly. The y-axis is labelled. Along the x-axis, the zero point and the frequency where the peak has its maximum are labelled and close to the arrow the unit of this axis is written.] y-axis: Energy Density Along the x-axis: 0 160.4 GHz [Above the graph to the right is the following formula, with the last inner parentheses only included to make the formula clear, since in the drawing the fractions are written above and below horizontal lines:] I(f) = (2hf 3 /c 2 )(1/(e hf/kT -1)) [Below the graph is written the following:] Science. It works, bitches. "
"The solid line represents the theoretical radiation for a blackbody at 2.73 K according to Planck's Law (derived as early as 1900 by Max Planck ). The formula, almost as written in the graph, can be found here . The only changes are that on Wikipedia, the frequency f is represented by the Greek letter ν (nu) and the temperature T is included as an independent variable, so I ( f ) becomes I ( v , T ). However, I ( v , T ) still represents the spectral radiance (similar to energy density). In this formula, h is the Planck constant, c is the speed of light in a vacuum, and k is the Boltzmann constant. The frequency ( f or v ) along the x -axis is measured in gigahertz . The curve peaks at 160.4 GHz. There is no scale or unit on the energy density on the y -axis. The theory is that the blackbody in question was the universe at the point when it had cooled down enough to allow photons to escape , 0.38 million years into its 13.8 billion years history. The photons that reach us today are the ones that have been travelling to us at lightspeed since then. As the light from astronomical objects suffers from redshift due to the expansion of the universe, and this shift becomes more pronounced with distance from the observer, this light displays in the infrared range. The title text praises viewers who can identify where this equation and corresponding graph come from (without consulting this wiki, of course). This comic was made into a T-shirt, but is no longer available. On the xkcd store, there was both an explanation for the title: And specifically an explanation for the graph: The above is a direct copy paste, with errors. The current wiki page of the COBE mission can be found at Cosmic Background Explorer on Wikipedia . [A graph with a curve that begins at zero, then peaks at a given frequency, indicated via a thin vertical line, and then fades down towards zero. It is possible to see the data points, which fit the curve perfectly. The y-axis is labelled. Along the x-axis, the zero point and the frequency where the peak has its maximum are labelled and close to the arrow the unit of this axis is written.] y-axis: Energy Density Along the x-axis: 0 160.4 GHz [Above the graph to the right is the following formula, with the last inner parentheses only included to make the formula clear, since in the drawing the fractions are written above and below horizontal lines:] I(f) = (2hf 3 /c 2 )(1/(e hf/kT -1)) [Below the graph is written the following:] Science. It works, bitches. "
55
"Useless"
"Useless"
"https://www.xkcd.com/55"
"https://imgs.xkcd.com/comics/useless.jpg"
"https://www.explainxkcd.com/wiki/index.php/55:_Useless"
"[Different mathematical equations, all with a heart on left side, and all ending up with question marks.] √♥ = ? cos ♥ = ? d/dx ♥ = ? [1 0]♥ = ? [0 1] F{♥} = 1/√2π ∫ ∞ -∞ f(t)e it♥ dt = ? [Caption below:] My normal approach is useless here. "
"Randall is attempting to apply mathematics to the concept of love to no avail. Specifically, he is attempting his "normal approach", which is a term used in mathematics for the method one typically uses to solve a certain type of problem. However, as love is not a well-defined mathematical entity, his normal approach is useless. Simply put: he's saying he has found no way of describing love using only the tools of mathematics. From the top, moving left to right, he tries the square root of love, the cosine of love, and the derivative of love with respect to x. He then attempts to left-multiply love by a 2x2 identity matrix , and finally he defines a function of love as a Fourier transform . These are all "normal approaches" to solving certain math problems. The message of the comic is that for someone who uses math to solve all their problems, defining love is impossible. It also indicates that love is not always a rational (or irrational) phenomenon. This comic has been made into a t-shirt in the xkcd store, with a Laplace transform in place of the bottom integral. Note: The Wikipedia links will provide far more detailed explanations of the mathematics. [Different mathematical equations, all with a heart on left side, and all ending up with question marks.] √♥ = ? cos ♥ = ? d/dx ♥ = ? [1 0]♥ = ? [0 1] F{♥} = 1/√2π ∫ ∞ -∞ f(t)e it♥ dt = ? [Caption below:] My normal approach is useless here. "
56
"The Cure"
"The Cure"
"https://www.xkcd.com/56"
"https://imgs.xkcd.com/comics/the_cure.jpg"
"https://www.explainxkcd.com/wiki/index.php/56:_The_Cure"
"[A charcoal drawing of Robert Smith's head and face.] [Caption below:] Robert Smith should do a cover of Coldplay's Clocks, so when he sings "Am I part of the cure or am I part of the disease?" we can say, "Ooh, we know this one!" "
"The "real face" is that of Robert Smith , best known as the singer of the musical group The Cure , hence the title. The joke in this comic is very simple: When Robert would sing the above lines of Coldplay 's song " Clocks ", fans of his music would know the answer: he's part of The Cure. In the title text, Randall notes that he has not tried to draw a real face in years, as he mainly does stick drawings. In that way this comic also sticks out. [A charcoal drawing of Robert Smith's head and face.] [Caption below:] Robert Smith should do a cover of Coldplay's Clocks, so when he sings "Am I part of the cure or am I part of the disease?" we can say, "Ooh, we know this one!" "
57
"Wait For Me"
"Wait For Me"
"https://www.xkcd.com/57"
"https://imgs.xkcd.com/comics/wait_for_me.jpg"
"https://www.explainxkcd.com/wiki/index.php/57:_Wait_For_Me"
"[Cueball and Megan stand facing one another.] Megan: Why didn't you wait for me? Cueball: I thought you were gone forever! [Megan throws out her arms, and Cueball is looking down.] Megan: I said I'd be back in a minute! Cueball: The... the seconds went fast at first, but then they started to drag on. Cueball: She was there for me. [Same scene as before, except Megan has her arms out less.] Megan: You had an affair in the 90 seconds I was gone?! Cueball: ...yes. [Cueball and Megan stand facing one another in a smaller panel.] Cueball: And we had a son. [Same scene as before.] Cueball: He'd be about your age now. "
"This comic juxtaposes a familiar exchange with a surreal outcome. Megan is returning after a short absence. Cueball reacts as if she had been gone for years, and admits to having an affair while waiting. In this comic, a familiar exchange occurs where one person asks the other why they did not wait. The humor lies in the improbability of him falling in love and having an affair within 90 seconds, the impossibility of him having a son in that time, and the ridiculous notion that the son would now be about Megan's current age. This is of course impossible, as it would imply that Cueball experienced twenty-ish years of life in what felt like 1.5 minutes for Megan. (He might conceivably have managed to have sex in that time span, which would fit with the experience of Cueball in 1068: Swiftkey ). Scott appears to be a friend of Randall . Comics 57 through 59 all have the title text Opening dialogue by Scott , forming a sort of informal mini-series inspired by him. They are: As there already was a comic released on Monday that week, the first of these three was released on Tuesday, then Wednesday and Friday. This may be related to the fact that this was the first week where the comics were not also released on LiveJournal . [Cueball and Megan stand facing one another.] Megan: Why didn't you wait for me? Cueball: I thought you were gone forever! [Megan throws out her arms, and Cueball is looking down.] Megan: I said I'd be back in a minute! Cueball: The... the seconds went fast at first, but then they started to drag on. Cueball: She was there for me. [Same scene as before, except Megan has her arms out less.] Megan: You had an affair in the 90 seconds I was gone?! Cueball: ...yes. [Cueball and Megan stand facing one another in a smaller panel.] Cueball: And we had a son. [Same scene as before.] Cueball: He'd be about your age now. "
58
"Why Do You Love Me?"
"Why Do You Love Me?"
"https://www.xkcd.com/58"
"https://imgs.xkcd.com/comics/why_do_you_love_me.jpg"
"https://www.explainxkcd.com/wiki/index.php/58:_Why_Do_You_Love_Me%3F"
"[Cueball and Megan are having a conversation. The same scene is shown for all panels.] Cueball: Why do you love me? Megan: I don't know; my heart never gave me a choice. Cueball: Aww. [Beat panel.] Megan: I wish it had. "
"Cueball asks "Why do you love me?" to Megan , a fairly common question that couples ask each other. She responds by saying, "My heart never gave me a choice," a seemingly very sentimental, romantic answer. However, after a beat panel , she effectively kills the romance of the moment by adding, "I wish it had," indicating that she would rather not have loved Cueball. Scott appears to be a friend of Randall Munroe . Comics 57 through 59 all have the title text Opening dialogue by Scott , forming a sort of informal mini-series inspired by him. They are: As there already was a comic released on Monday that week, the first of these three was released on Tuesday, then Wednesday and Friday. This may be related to the fact that this was the first week were the comics were not also released on LiveJournal . [Cueball and Megan are having a conversation. The same scene is shown for all panels.] Cueball: Why do you love me? Megan: I don't know; my heart never gave me a choice. Cueball: Aww. [Beat panel.] Megan: I wish it had. "
59
"https://www.xkcd.com/59"
"[Megan and Blondie are talking.] Blondie: What do you want to do when you graduate? [Same scene as before.] Megan: I want to become a lighthouse operator. Blondie: Oh? Megan: Yeah. [Cut to scene of lighthouse with text overlaid.] Megan: Lighthouses are built on interesting pieces of coast, so I'll have an interesting place to walk and swim, and great views of all kinds of weather. I'd feel good about myself and my work every single day. [Cut back to Megan and Blondie. Megan has her arms up.] Megan: I'd get to be the girl in the tower, only I'd be the one rescuing people. [Megan now has her arms down.] Megan: Why, what do you want to do? Blondie: I'm going to grad school. I don't really know why. [Same scene as before.] Megan: Wanna come hang in my lighthouse over breaks? Blondie: ...yeah. "
"Megan and a young Blondie (in her first appearance) discuss their plans for life after college. Megan has taken the increasingly unusual choice of pursuing a career as a lighthouse operator , a path that has become increasingly less traveled, as lighthouses have become ever more automated and supplanted by other solutions. Before GPS technology, lighthouses were invaluable markers of where dangers to marine navigation, such as shallow reefs or coastal headlands, were located. Megan likes the idea of subverting the trope of the helpless maid in the tower who needs saving, by helping to save seafarers by operating a lighthouse that helps them to find their way safely back home. When it comes to her turn to answer her own question, Blondie answers that she plans to pursue postgraduate education , but admits that she has no purpose for doing so. After obtaining an undergraduate / bachelor's degree, graduate school is the next level of education, where students pursue a master's or doctoral degree . Augmenting one's education with post-graduate studies is a conventional career path, and would imply that the student has a definite plan for their career, yet some people may attend grad school only because it is conventional, without having any definite plan for their career. This appears to be the case for Blondie, contrasted with Megan's choice of a seemingly blue collar / unskilled career — one might expect such a career to indicate someone who has no specific career plan, yet Megan seems to know her exact purpose, unlike Blondie. The fact that Blondie then accepts an invitation to spend her breaks at Megan's lighthouse suggests that she finds this a more attractive prospect than her more conventional path. Other comics with a similar theme about finding or taking unexplored paths, instead of fitting into the mold, include 137: Dreams and 267: Choices: Part 4 . Scott appears to be a friend of Randall Munroe . Comics 57 through 59 all have the title text Opening dialogue by Scott , forming a sort of informal mini-series inspired by him. They are: As there already was a comic released on Monday that week, the first of these three was released on Tuesday, then Wednesday and Friday. This may be related to the fact that this was the first week where the comics were not also released on LiveJournal . [Megan and Blondie are talking.] Blondie: What do you want to do when you graduate? [Same scene as before.] Megan: I want to become a lighthouse operator. Blondie: Oh? Megan: Yeah. [Cut to scene of lighthouse with text overlaid.] Megan: Lighthouses are built on interesting pieces of coast, so I'll have an interesting place to walk and swim, and great views of all kinds of weather. I'd feel good about myself and my work every single day. [Cut back to Megan and Blondie. Megan has her arms up.] Megan: I'd get to be the girl in the tower, only I'd be the one rescuing people. [Megan now has her arms down.] Megan: Why, what do you want to do? Blondie: I'm going to grad school. I don't really know why. [Same scene as before.] Megan: Wanna come hang in my lighthouse over breaks? Blondie: ...yeah. "
60
"Super Bowl"
"Super Bowl"
"https://www.xkcd.com/60"
"https://imgs.xkcd.com/comics/super_bowl.jpg"
"https://www.explainxkcd.com/wiki/index.php/60:_Super_Bowl"
"[A green car with text above and next to it.] My hobby: While everyone is watching the Super Bowl, feeling smugly superior because they're "Only watching for the ads," I steal cars. In a distant future (2015), Randall (or Cueball ) spends his time differently during the Super Bowl - see 1480: Super Bowl . (This was the second time that two xkcd comics have shared the exact same name .) In between this comic and the one nine years later, no other comics came out related to the Super Bowl. The year after (2016), there was a comic ( 1640 ) about the Super Bowl, and in 2018 a comic ( 1951 ) appeared about a Super Bowl watch party. "
"The third in the " My Hobby " series. The Super Bowl is the championship American football game of the National Football League , which is usually played each February, and the final game of the 2006 season, Super Bowl XL , was played on the evening of 2006-02-05, the day before this comic was released. As the game is one of the most watched television broadcasts in North America, advertising during the game has become increasingly expensive (among the most expensive advertising rates of any broadcast) to the point where corporations produce their best, most expensive advertisements to air during the game, to ensure that they would get value out of the expensive spots. The Super Bowl has thus become notorious for the "best" commercials, with some viewers purportedly tuning in solely to see the commercials, rather than the actual football game. News reports the next day often highlight the best and worst Super Bowl commercials, as do websites devoted to Super Bowl commercials. Realizing that the Super Bowl is viewed by a large percentage of the population, Randall , somewhat tongue-in-cheek, states that those people would be quite distracted during that time, and therefore it would be possible to steal cars without fear of being caught. The title text takes this even further, suggesting that the entire Super Bowl was invented entirely for the purpose of being a distraction for car thieves. Naturally, the addition of the ads would make this even more effective, as it would attract even more viewers and ensure that they stayed in front of the TV during commercial breaks as well as the game. The phrase "I steal cars" also provides a contrast to the fact that many viewers are only watching for the advertisements, making their smug sense of superiority seem petty compared to the fact that they but not Randall are not stealing cars and that they therefore are morally superior to Randall in this respect. This calls into question whether or not they really are significantly superior by comparing this marginal superiority to not being criminals. Alternatively, Randall may resent these people for feeling superior even though they aren't actually superior (at least in the eyes of Randall) and therefore steal their cars as punishment. Or Randall might be implying that they have no reason to being smug as they are being duped into having their cars stolen, and the thief is the one in the best position to be smug. Randall may have chosen to use a car as a reference to the large number of car commercials that play during the Super Bowl, in addition to the ease of stealing a car at that time. [A green car with text above and next to it.] My hobby: While everyone is watching the Super Bowl, feeling smugly superior because they're "Only watching for the ads," I steal cars. In a distant future (2015), Randall (or Cueball ) spends his time differently during the Super Bowl - see 1480: Super Bowl . (This was the second time that two xkcd comics have shared the exact same name .) In between this comic and the one nine years later, no other comics came out related to the Super Bowl. The year after (2016), there was a comic ( 1640 ) about the Super Bowl, and in 2018 a comic ( 1951 ) appeared about a Super Bowl watch party. "
61
"https://www.xkcd.com/61"
"[A hairy man.] Man: Look, I know you think that since I walked out she could use a guy like you. But trust me. That woman has got a lot going on, and you want none of it. Man: Get out while you still can. [Printed across the bottom of the panel.] Stacey's dad. "
"This comic refers to the song " Stacy's Mom " by Fountains of Wayne (See the music video on YouTube). As the background singers repeatedly say, "Stacy's mom has got it goin' on." Although Randall has used the wrong spelling of 'Stacy'. The song is from the perspective of a young teenage boy who has a crush on his best friend's mother — 'Stacy's Mom' — and has deluded himself into thinking that she might like him back. In one verse, he tells Stacy "I know that you think it's just a fantasy, but since your Dad walked out your Mom could use a guy like me," and this is the line the comic is referencing, with Stacy's Dad (drawn the same way as Hairy , making this his first appearance) directly echoing the line and explaining why he left Stacy's Mom, suggesting that the singer do the same. The line "Stacy's Mom has got it going on" is repeated throughout the song, and in context simply means that Stacy's Mom is very attractive. Here, however, Stacy's Dad changes it, saying that she "has a lot going on," which means that she has issues that would make a relationship difficult. The humor comes from the fact that, in the song, it is very clear that the singer does not actually have a chance with Stacy's Mom and is merely kidding himself, as he is still just a kid. But in the comic, Stacy's Dad appears to be taking the situation completely seriously, and is worried enough about the possibility of Stacy's Mom and the boy getting together that he feels the need to warn him away. The title text is referencing the second verse, which begins: "Stacy remember when I mowed your lawn." Mowing the lawn is the sort of chore that a kid might get paid to do for a friend's parent, and in the song, this is meant to emphasize that Stacy's Mom sees the singer as a child, not as a potential partner. But here, Stacy's Dad seems to be implying that mowing the lawn is something that Stacy's Mom made him — and possibly all her previous partners — do for her, and so her getting the boy to do it is actually a sign that she is interested in him. The song Stacy's Mom was again referenced in 575: Tag Combination . [A hairy man.] Man: Look, I know you think that since I walked out she could use a guy like you. But trust me. That woman has got a lot going on, and you want none of it. Man: Get out while you still can. [Printed across the bottom of the panel.] Stacey's dad. "
62
"Valentine - Karnaugh"
"Valentine - Karnaugh"
"https://www.xkcd.com/62"
"https://imgs.xkcd.com/comics/karnaugh.jpg"
"https://www.explainxkcd.com/wiki/index.php/62:_Valentine_-_Karnaugh"
"[Squiggly heart design.] You make me feel so much it all runs together I wish I could tell you [Crisscrossing heart design. Cueball and Megan on opposite sides of big heart.] So few words for so many feelings crisscrossing my heart [Heart matrix design.] A matrix of desire Tangled relations I can't simplify [Karnaugh map of hearts.] I wish I could find the Karnaugh map for love. "
"A Karnaugh map is a Boolean algebra tool that is used to simplify expressions. The final picture, the one that looks like a crossword puzzle, is similar to the way that a Karnaugh map is used on a Boolean truth table, to identify areas that can be simplified. This PDF document shows how the process is used to simplify logic circuits. The lament of the Valentine is that feelings don't yield themselves to the same kind of analysis. This comic has four pictures with lines of text alongside them. The text can be used to understand the picture. The first three pictures show love to become more coherent and well-defined but yet complicated. The last picture and text alongside it show Cueball 's desire that there should be a way to simplify complications in love, just like Karnaugh maps for Boolean expressions. The first line means that love is such an overwhelming feeling that it is hard to understand it and even harder to explain. The picture alongside has incoherent lines depicting the feelings of someone in love and hearts represents the overwhelming love. The second picture and related text mean that the feelings are now identified to some extent but are numerous, and there are too few words to explain them. The picture depicts Cueball and Megan on separate side of his heart crisscrossed by many feelings. It shows that his inability to explain his feelings is like a barrier between them. The third picture shows that Cueball has a much better understanding of love and now sees it as a matrix of desires and tangled relations, but it is still very complex to fully understand love. The fourth picture shows a Karnaugh map that Cueball wishes he could find in the future to solve the matrix of desires and tangled relations that is love. [Squiggly heart design.] You make me feel so much it all runs together I wish I could tell you [Crisscrossing heart design. Cueball and Megan on opposite sides of big heart.] So few words for so many feelings crisscrossing my heart [Heart matrix design.] A matrix of desire Tangled relations I can't simplify [Karnaugh map of hearts.] I wish I could find the Karnaugh map for love. "
63
"Valentine - Heart"
"Valentine - Heart"
"https://www.xkcd.com/63"
"https://imgs.xkcd.com/comics/valentine.jpg"
"https://www.explainxkcd.com/wiki/index.php/63:_Valentine_-_Heart"
"[A Valentine's Day heart bordered with wavy red lace-like pattern with text:] "
"The comic shows a Valentines card that starts off nicely, but then " escalates quickly " becoming very unromantic although probably very honest, that the only purpose of this card is getting the receiver into bed. It says that if this is not the case, if she (or he) doesn't want to go naked after receiving this card, then it is not really meant (i.e. their heart is not in it). The title text implies that this is being offered as a Valentine that someone might give and then "pretend" that they were kidding. Which seems to imply that they would not, in fact, be kidding, that this represents their real feelings. A funny thing is also that the text on the card implies that if the card indeed does get the receiver naked, that the action of giving it was truly meant. In that case, the giver would always deny that it was not meant and claim he/she is truly in love. Of course this cannot be true, since getting laid was the main motivation of appreciating the 'loved' one. "In it" could be an intentional sexual innuendo. [A Valentine's Day heart bordered with wavy red lace-like pattern with text:] "
64
"Solar Plexus"
"Solar Plexus"
"https://www.xkcd.com/64"
"https://imgs.xkcd.com/comics/solar_plexus.jpg"
"https://www.explainxkcd.com/wiki/index.php/64:_Solar_Plexus"
"[Black Hat and Cueball are talking to each other.] Black Hat: Asolarplexussayswhat? Cueball: What? [Beat panel.] [Beat panel.] [Black Hat punches Cueball in the solar plexus.] "
"The solar plexus is a network of interconnecting nerves that is centered in the area of the abdomen near the stomach. A blow to this area is painful and the cause of the feeling called "getting the wind knocked out of you" and is prevalent in media. The trick "An[incomprehensible mumble]sayswhat" is a juvenile taunt that tricks a person into calling themselves a name. Black Hat resolves the solar plexus joke with a punch to Cueball in the solar plexus as opposed to a normal punch(line). The title text mentions truthfully that it hurts to be hit there. [Black Hat and Cueball are talking to each other.] Black Hat: Asolarplexussayswhat? Cueball: What? [Beat panel.] [Beat panel.] [Black Hat punches Cueball in the solar plexus.] "
65
"Banter"
"Banter"
"https://www.xkcd.com/65"
"https://imgs.xkcd.com/comics/banter.jpg"
"https://www.explainxkcd.com/wiki/index.php/65:_Banter"
"[Two Cueball like characters have a discussion. They are drawn the same in all eight panels.] Guy: Man, she's hot Friend: Whatever, you are so gay. Guy: C'mon, everyone knows you're the gay one. Friend: Hey, your mom's pretty masculine, but sleeping with her doesn't make me gay. Guy: Fag. Friend: Ass pirate. Guy: Fudge packer Friend: Cock jockey Guy: Cum dumpster. [Beat panel.] Guy: Okay, seriously, are you gay? Because if you've been holding out on me, we're missing out. Friend: No, it's cool. Guy: OK, me neither. [Beat panel.] [Beat panel.] "
"Two guys are trash-talking each other with homophobic comments and your mom jokes . It goes somewhat astray and becomes awkward when the first guy makes a pass at the second guy and is rejected. Part of the element of the humor in this comic stems from a common assertion that the most-homophobic of men are the most likely to be a closeted homosexual . Another element is the incredible awkwardness of the end conversation. Fag , ass pirate , fudge packer , and cock jockey are all insults for a homosexual man. Cum dumpster can apply to both men and women (usually conveying sluttiness ). Randall's title text, that he mock-held this conversation with a friend in a TGIF restaurant, indicates how awkward this would be in real life. Even the waitress, a bystander, is put off by it. [Two Cueball like characters have a discussion. They are drawn the same in all eight panels.] Guy: Man, she's hot Friend: Whatever, you are so gay. Guy: C'mon, everyone knows you're the gay one. Friend: Hey, your mom's pretty masculine, but sleeping with her doesn't make me gay. Guy: Fag. Friend: Ass pirate. Guy: Fudge packer Friend: Cock jockey Guy: Cum dumpster. [Beat panel.] Guy: Okay, seriously, are you gay? Because if you've been holding out on me, we're missing out. Friend: No, it's cool. Guy: OK, me neither. [Beat panel.] [Beat panel.] "
66
"Abusive Astronomy"
"Abusive Astronomy"
"https://www.xkcd.com/66"
"https://imgs.xkcd.com/comics/abusive_astronomy.jpg"
"https://www.explainxkcd.com/wiki/index.php/66:_Abusive_Astronomy"
"Identifying star clusters: [Image of a star cluster.] This is the Pleiades , asshole. Orion's Belt: [Image of Orion's Belt.] Only a moron couldn't find it. This is the Big Dipper : [Image of the Big Dipper.] What the hell is wrong with you? As noted in the title text, the drawing for this comic was originally done in pencil, then inverted. Here is a re-inverted version of the file, to show (approximately) what the original drawing looked like. Alternatively, Randall may be using sarcasm when saying that the medium is pencil on paper, since it would be incredibly impractical and nearly impossible to draw the uniform black background while leaving white gaps for stars (assuming it was not inverted). At the very bottom of the about page on xkcd, Randall answers the question What is your favorite astronomical entity? with The Pleiades . "
"An asterism is a pattern of stars that forms some sort of perceived shape in the night sky. Some of these are patterns used to name regions of the sky, as constellations. Modern astronomy organizes the sky into 88 constellations, but different cultures saw different patterns in the same night sky, going back at least as far as the Babylonians, and there are many other patterns and grouping of stars. The Pleiades (or Subaru ), Orion's belt , and the Big Dipper are among the most common asterisms that we recognize today and are among the first taught to people with an interest in astronomy. The Pleiades is an open star cluster in the constellation of Taurus. It is a group of stars that formed from the same nebula and are moving together. Orion's belt comprises three stars that appear close in the sky, but are in fact at great distance from each other. The Big Dipper is part of the constellation Ursa Major. It can be used to help find the north pole star Polaris , which is an aid to night-time navigation. During planetarium tours, the tour guide will point out popular constellations and stars; sometimes they will ask a question to get the audience involved in the presentation. Usually these people are big on showing the wonder of the galaxy and are all smiles, but people have bad days. The comic is presenting an especially aggressive way of introducing the night sky. When astronomers in the Northern Hemisphere are showing stars to people, there will frequently be someone who points to the Pleiades and says, "There's the Big Dipper!" (both appear as a trapezium of stars, with a handle, though the Pleiades is much smaller). This gets frustrating about the 100th time that you encounter this error. So, this comic could show someone releasing their frustration on the misinformed public by pointing out that what they just pointed at is actually the Pleiades, then, pointing out that you can always locate the Pleiades by following the line of the stars in the belt of Orion, then, pointing out the REAL Big Dipper. In the title text, Randall explains that he drew this comic as a line drawing on white paper, using only a pencil. The image was later inverted for publication. Identifying star clusters: [Image of a star cluster.] This is the Pleiades , asshole. Orion's Belt: [Image of Orion's Belt.] Only a moron couldn't find it. This is the Big Dipper : [Image of the Big Dipper.] What the hell is wrong with you? As noted in the title text, the drawing for this comic was originally done in pencil, then inverted. Here is a re-inverted version of the file, to show (approximately) what the original drawing looked like. Alternatively, Randall may be using sarcasm when saying that the medium is pencil on paper, since it would be incredibly impractical and nearly impossible to draw the uniform black background while leaving white gaps for stars (assuming it was not inverted). At the very bottom of the about page on xkcd, Randall answers the question What is your favorite astronomical entity? with The Pleiades . "
67
"Nerd Girls"
"Nerd Girls"
"https://www.xkcd.com/67"
"https://imgs.xkcd.com/comics/nerd_girls.jpg"
"https://www.explainxkcd.com/wiki/index.php/67:_Nerd_Girls"
"[Girl with shoulder length brown hair and glasses, wearing a shirt which says "Do not meddle in the affairs of dragons".] Girl: At least, thanks to your constant fawning, we have an excuse for our social ineptness. What's yours ? "
"The stereotypical nerd is socially inept and has an obsession with a non-mainstream hobby such as Dungeons and Dragons . Nerd males are also typically represented as treating all women (including female nerds) with reverence and awkward fawning due to their supposed inexperience and lack of female company in comparison to other males. In the comic, the nerd girl uses this as an excuse for her social ineptitude. The T-shirt the girl is wearing contains the text "Do not meddle in the affairs of Dragons," which is an actual text used for T-shirts, continuing with "for you are crunchy and taste good with ketchup!" This text is a modified version of a quote from Tolkien's The Fellowship of the Ring : "Do not meddle in the affairs of Wizards, for they are subtle and quick to anger." To all the high schoolers who are at the stage when they begin to find dates, Randall is saying that it is nothing personal, i.e. he is not trying to insult them by pointing this situation out. [Girl with shoulder length brown hair and glasses, wearing a shirt which says "Do not meddle in the affairs of dragons".] Girl: At least, thanks to your constant fawning, we have an excuse for our social ineptness. What's yours ? "
68
"Five Thirty"
"Five Thirty"
"https://www.xkcd.com/68"
"https://imgs.xkcd.com/comics/five_thirty.jpg"
"https://www.explainxkcd.com/wiki/index.php/68:_Five_Thirty"
"Comics from 5:30 AM [A succession of unrelated and completely random panels.] Cueball: It's 80's night at the club. Wanna go? Friend: There is no Tuesday. Cueball: Jack the Ripper or Jack Black? [Cueball in this panel is holding a glinting sword.] Friend: You crashed my helicopter! Cueball: Verily! [A small figure is talking with a larger figure.] Figure 1: Basically, neither of us have shins. Figure 2: Over and out. [Two men are shown: one with three arms, and another with just two. All arms have round appendages at their ends.] Men: shitshitshitshitshitshitdaylightsavingsshitshitshitshitsh [Two figures with pumpkins (carved with faces) for heads.] Figure 1: You're out of ointment and out of time! [A diagram of a right-angled triangle, with a theta at the smallest angle.] FUCK THE COSINE Friend: Does being a mermaid for five minutes make you gay? Cueball: I hope so! [The friend is holding a gun to Cueball's head.] Friend: Barbershops are for pussies. Friend: My hair is bleeding. Cueball: √3 [Cueball seems to be walking on the ceiling.] Cueball: Bachelor party! [Warning sign with picture of an ant.] WARNING: STRETCHY DEATH "
"At 5:30 AM, one's sleep-deprived or prematurely-roused mind sometimes comes up with things that seem like nonsense later. None of the twelve panels in this comic seem to have any correlation with one another, each one being its own "story," and none of them really make any sense. It is unknown whether Randall really wrote this comic while awake at 5:30 in the morning, or if he wrote it while completely alert and is trying to pass off his rejected ideas by saying what one's mind may experience when trying to process information at an hour when the person is not used to being awake. The title text could actually refer to two different panels. If a person chooses to read the comic left-to-right, top-to-bottom (which is more likely given that this is the order in the official transcript), the eighth panel could be the one with where Cueball asks "Does being a mermaid for five minutes make you gay?" However, if a person chooses to read the comic top-to-bottom, left-to-right, the eighth panel will instead be the one with Cueball hanging upside down shouting "Bachelor party!" Comics from 5:30 AM [A succession of unrelated and completely random panels.] Cueball: It's 80's night at the club. Wanna go? Friend: There is no Tuesday. Cueball: Jack the Ripper or Jack Black? [Cueball in this panel is holding a glinting sword.] Friend: You crashed my helicopter! Cueball: Verily! [A small figure is talking with a larger figure.] Figure 1: Basically, neither of us have shins. Figure 2: Over and out. [Two men are shown: one with three arms, and another with just two. All arms have round appendages at their ends.] Men: shitshitshitshitshitshitdaylightsavingsshitshitshitshitsh [Two figures with pumpkins (carved with faces) for heads.] Figure 1: You're out of ointment and out of time! [A diagram of a right-angled triangle, with a theta at the smallest angle.] FUCK THE COSINE Friend: Does being a mermaid for five minutes make you gay? Cueball: I hope so! [The friend is holding a gun to Cueball's head.] Friend: Barbershops are for pussies. Friend: My hair is bleeding. Cueball: √3 [Cueball seems to be walking on the ceiling.] Cueball: Bachelor party! [Warning sign with picture of an ant.] WARNING: STRETCHY DEATH "
69
"Pillow Talk"
"Pillow Talk"
"https://www.xkcd.com/69"
"https://imgs.xkcd.com/comics/pillow_talk.jpg"
"https://www.explainxkcd.com/wiki/index.php/69:_Pillow_Talk"
"Cueball: Staring at the ceiling, she asked me what I was thinking about. Cueball: I should have made something up. Cueball: The Bellman-Ford algorithm makes terrible pillow talk. "
"The Bellman-Ford algorithm is an algorithm that calculates the shortest path(s) through a weighted digraph or collection of connected nodes or vertices. The "Wexler" in the title text refers to Wexler's algorithm, which is used to deal with the inverse problem of electrical impedance tomography , or simply stated: the electrical conductivity of an (inhomogenous) object. Both of these would make terrible pillow talk . Pillow talk is the conversation made by lovers after they have had sex, and is usually relaxed and intimate instead of technical. Cueball: Staring at the ceiling, she asked me what I was thinking about. Cueball: I should have made something up. Cueball: The Bellman-Ford algorithm makes terrible pillow talk. "
70
"Guitar Hero"
"Guitar Hero"
"https://www.xkcd.com/70"
"https://imgs.xkcd.com/comics/guitar_hero.jpg"
"https://www.explainxkcd.com/wiki/index.php/70:_Guitar_Hero"
"[On a stage, Megan is in the background as a singer holding a microphone. In the center is Hairy with an electric guitar. The catwalk has bumps to resemble the tracks of Guitar Hero.] [Caption above the stage]: When I'm in a rock band, I'm gonna do a cool, mellow song. Then in the middle I'll stop, announce "this part is just to be an asshole to people playing Guitar Hero," and then flail wildly on the strings for 30 seconds."
"Guitar Hero is a series of video games (originally a single game) distributed by Activision . In the game, players simulate playing the guitar on famous guitar songs using a plastic guitar-shaped controller with five color-coded buttons on the neck representing guitar frets and a rocker bar on the body simulating a strumming motion. The game now includes other instruments such as drums and vocals, although not at the time this comic was published. While the player plays the game, an animated band is shown on the upper half of the screen, and an extended guitar neck is shown vertically on the bottom half of the screen with horizontal frets, often called the "note highway." As the song progresses, coloured markers or "gems" indicating notes travel down the screen in time with the music; the note colours and positions match the five fret keys on the guitar controller. Once the notes reach the bottom, the player must play the indicated notes by holding down the correct fret buttons and hitting the strumming bar in order to score points. The image in the comic is similar to what is shown when playing Guitar Hero . In this comic, Randall suggests that, were he in a real rock band, he would perform a mellow song, but intentionally put a complicated guitar solo in, not for musical value, but solely to antagonize Guitar Hero players with an impossible solo. As the comic suggests, a random flailing would likely make for a very difficult passage to play in Guitar Hero . This is highlighted by the previous statement that the song would otherwise be mellow, lulling the player into a false sense that the song was easy to play and relaxing. Even worse for Guitar Hero players, if there was anyone who is good enough to play the solo, they would still have no fun playing the song if it is otherwise very mellow. Probably, the "impossible solo" proposed here would turn useless, as there are some songs where the artist actually flails the guitar, and the developers translated that in gameplay as a bonus where the players can freely spam their controller/guitar for extra points. The title text refers to a mechanic in Guitar Hero called "Star Power." Normally, when a player misses too many notes in a short time, their character is booed off the stage, and they have to restart. Using Star Power temporarily boosts the score from each note, so the player can clear a difficult section of the song even if they haven't hit most of the notes. So, when faced with Randall's impossible guitar solo, most players will immediately use Star Power to survive it. However, it takes time to build up Star Power, and it all gets expended at once, so if the song has a second stretch of wild flailing, the player won't be able to escape and will fail. (Also note that in Guitar Hero III: Legends of Rock and many other titles of the series, a full meter of Star Power lasts for eight measures, so as long as the song is mildly fast (80BPM would more than suffice for a 4/4 or 12/8 time signature), 30 seconds would be enough already.) [On a stage, Megan is in the background as a singer holding a microphone. In the center is Hairy with an electric guitar. The catwalk has bumps to resemble the tracks of Guitar Hero.] [Caption above the stage]: When I'm in a rock band, I'm gonna do a cool, mellow song. Then in the middle I'll stop, announce "this part is just to be an asshole to people playing Guitar Hero," and then flail wildly on the strings for 30 seconds."
71
"In the Trees"
"In the Trees"
"https://www.xkcd.com/71"
"https://imgs.xkcd.com/comics/in_the_trees.jpg"
"https://www.explainxkcd.com/wiki/index.php/71:_In_the_Trees"
"[Cueball is standing in a forest.] Cueball: We made it so far together but then I lost you in the trees. [A closer view of Cueball.] Cueball: Finally. "
"This comic focuses on dark humor. In the first panel, the viewer is led to believe that it is a comic lamenting on the loss of love, as it states, "We made it so far together, but then I lost you in the trees." However, when we read the second panel ("Finally"), it becomes clear that the joke is that the loss of this "love" is what he had been hoping for all along. The supposed pain that came from such losing a long relationship came not from lamenting the loss of something he put so much effort into, but instead into the fact that it took so long to get there. The title text just furthers this idea. There is a similar twist in comics 334: Wasteland and 1042: Never . [Cueball is standing in a forest.] Cueball: We made it so far together but then I lost you in the trees. [A closer view of Cueball.] Cueball: Finally. "
72
"Classhole"
"Classhole"
"https://www.xkcd.com/72"
"https://imgs.xkcd.com/comics/classhole.jpg"
"https://www.explainxkcd.com/wiki/index.php/72:_Classhole"
"Cueball: How did you spend your morning? Black Hat: Feeding rocks to children in the park. Cueball: Your sociopathic abuse of random strangers staggers me. Black Hat: I aspire to have more creativity than the common asshole. Black Hat: I'm more of a classy asshole -- A class-hole, if you will. For example, I like poking tiny holes in styrofoam noodle cups at the grocery store -- Black Hat: Thanks to me, someone gets surprise boiling water in the lap. Cueball: I am in awe. Black Hat: It's even more fun to do to condoms. "
"The subject of this comic is Black Hat himself. He admits to being an asshole, a profanity that describes someone who does things that antagonize, irritate, or anger others (either intentionally or incidentally). While a common example might be someone who weaves in and out of traffic, or someone who parks across two parking spaces, Black Hat is "more creative." This also suggests that, while most people described as assholes are either ignorant or selfish, Black Hat seems to intentionally behave this way strictly to be an asshole and not for any self-benefit. He claims to be a "classy asshole," or as he coins the portmanteau , a "class-hole." He seems to equate creativity with class, although that seems like a leap. In any event, this is another early Black Hat strip that, for the first time, explicitly sets out that he goes out of his way to wreak havoc. Among his "pranks," he suggests poking holes in grocery noodle cups. These are pre-packaged cups filled with dried noodles and dried soup mix (either in a separate pouch, or loose in the cup) to which one adds boiling water, which both boils the pasta and dissolves the soup mix to become the soup/broth. By poking holes in the cup, Black Hat ensures that someone pouring boiling water in the cup would have it leak all over them, causing them great surprise and pain. He also suggests poking holes in condoms , which could cause even more serious consequences. This form of contraceptive sabotage is a way to cause unintended pregnancy or sexually transmitted disease infection. Sabotage may be by someone acting maliciously at random (such as poking holes at the store pre-purchase) or by one of the participants to attempt to cause a pregnancy when the other partner does not want it, often occurring as part of reproductive abuse. [1] The 2013 movie The Priest's Children describes a similar campaign. The title text explains that the word was first introduced to Randall (and probably to the world) by a friend of his named Beth. Cueball: How did you spend your morning? Black Hat: Feeding rocks to children in the park. Cueball: Your sociopathic abuse of random strangers staggers me. Black Hat: I aspire to have more creativity than the common asshole. Black Hat: I'm more of a classy asshole -- A class-hole, if you will. For example, I like poking tiny holes in styrofoam noodle cups at the grocery store -- Black Hat: Thanks to me, someone gets surprise boiling water in the lap. Cueball: I am in awe. Black Hat: It's even more fun to do to condoms. "
73
"Zeppelin"
"Zeppelin"
"https://www.xkcd.com/73"
"https://imgs.xkcd.com/comics/zeppelin.jpg"
"https://www.explainxkcd.com/wiki/index.php/73:_Zeppelin"
"Cueball: What time is it? [Picture of a Zeppelin style watch, indicating the time about 12:13 o'clock.] [Cueballs look up at the sky.] [A huge Zeppelin is visible in the sky.] "
"A Zeppelin is a type of rigid dirigible aircraft, used in the early part of the 20th century for commercial airline traffic. They were well known for being the most luxurious, comfortable air travel of the time. The Hindenburg disaster, as well as World War II, led to the end of their use as commercial airliners. Also associated with the Zeppelin name is a particular design of wristwatches, [1] notable for having the word "Zeppelin" at the top of the dial, at or under where the number 12 would be. In this comic, Randall implies that, since the hour hand of the watch is pointing to the word Zeppelin, it is time for a Zeppelin to appear in the sky. The title text refers to the webcomic Buttercup Festival , which, at the time of this comic, was defunct. It was later revived by the author then defuncted again in 2015 and revived, again, in 2019. As of 18/07/20, the comic is running its third series. It is a tribute to Buttercup festival in the way it interprets things in the world naïvely and literally to achieve humour, in a simple yet effective and uncontrived way. Cueball: What time is it? [Picture of a Zeppelin style watch, indicating the time about 12:13 o'clock.] [Cueballs look up at the sky.] [A huge Zeppelin is visible in the sky.] "
74
"Su Doku"
"Su Doku"
"https://www.xkcd.com/74"
"https://imgs.xkcd.com/comics/su_doku.jpg"
"https://www.explainxkcd.com/wiki/index.php/74:_Su_Doku"
"[A square divided into 2×2 squares, the top-right one has an 1 in it, the bottom-right one has a 0, the two left ones are empty.] Binary Su Doku "
"Su Doku (Japanese for "single number," and now usually written as "sudoku") is a type of number puzzle, in which the player must place digits in a matrix field in the correct arrangement, such that they do not repeat within given domains. The most common arrangement is a 9×9 grid subdivided into nine 3×3 grids, into which the nine non-zero digits of the normal decimal counting system must be inserted, with no digit being allowed to appear twice in a horizontal or vertical row or in each individual 3×3 grid. The number and combination of pre-filled squares determines the difficulty of the puzzle. However, Randall presents a 2x2 binary sudoku puzzle which isn't subdivided. The joke is that the binary system has only two digits (0 and 1), and as a result binary sudoku puzzles would be trivially easy and thus pointless. The puzzle in the comic would be completed by filling 0 in the top-left and 1 in the bottom-left empty box. The only other possible grid would have the 0s and 1s swapped. This fulfills the criterion of having no repeated digits in any row, column or cell. The title text appears to reference a series of published sudoku puzzle books called "Martial Arts Sudoku". The difficulty of each book is denoted by a martial arts belt color, with each color representing a certain skill level. A red belt is a rather high level, second only to the black belt. When applied to binary sudokus, a sudoku with one number given would be the most difficult one (though still trivial) and thus be a black belt. This sudoku has two numbers given, hence the medium red belt level. [A square divided into 2×2 squares, the top-right one has an 1 in it, the bottom-right one has a 0, the two left ones are empty.] Binary Su Doku "
75
"Curse Levels"
"Curse Levels"
"https://www.xkcd.com/75"
"https://imgs.xkcd.com/comics/curse_levels.jpg"
"https://www.explainxkcd.com/wiki/index.php/75:_Curse_Levels"
"My hobby: mixing curse levels Cueball: What a gosh-darned cunt. "
"In this fourth " My Hobby " strip, the hobby is mixing curse levels. Curse words (aka: swear words/profanities) are disrespectful words that are typically impolite to use in public. As noted in the strip, there are "levels" of curse words ranging from those "mild" words that are more acceptable to use, to those "severe" words that are considered very impolite (the milder curse words can be used on network television in the US, for example, while severe ones can not). Although they cannot be exactly defined, they roughly fit into "safe"(heck, gosh, dang, etc.),"mild"(d*mn, s**t, h*ll and so forth) and "severe"(those that refer to more suggestive things than the others, as well as racial slurs and such). One usually uses milder cursing ("safe") because either they personally don't feel comfortable using the more severe words, or because it would not be appropriate in the context (such as on network television, in the presence of children, etc.) Thus, mixing mild and severe curses in one usage does not usually occur, as the effect achieved by keeping the one curse word mild is negated by using another that is severe. In a mild curse, "gosh-darned" is typically used as a minced oath of "God-damned" when the latter would be inappropriate. This is mixed with " cunt " — a vulgar term for the female genitalia, considered the most offensive swear word in many English-speaking countries. My hobby: mixing curse levels Cueball: What a gosh-darned cunt. "
76
"Familiar"
"Familiar"
"https://www.xkcd.com/76"
"https://imgs.xkcd.com/comics/familiar.jpg"
"https://www.explainxkcd.com/wiki/index.php/76:_Familiar"
"[Hairy and Megan are talking] Megan: I worry that I'm just with you because it's familiar. Of course no one else compares. I've known you for so long that I'd have to spend years with someone to build up this kind of connection and I daren't let you go of you long enough to let that happen. Megan: But I guess this is really all I can ask for. I'm happy with you; I should stop worrying. [Megan takes Hairy's hand.] Hairy: This is probably a bad time to bring this up, but I don't actually like you. "
"Megan tells her boyfriend ( Hairy ) her reservations about their relationship: she's happy with him, she thinks he doesn't compare to anyone else, and they have a strong connection built up over the course of years, but she's worried that all this is just because they've been dating so long that she hasn't had the opportunity to experience potentially better relationships. However, she recognizes that what she has should be enough, and resolves to stop worrying. Hairy responds to this by saying that he doesn't even like her, recognizing that it's relatively poor timing to say so after her expression of love (albeit a rather ambivalent one). The title text is a sad-face emoticon, representing either Megan's sadness about his dislike of her, his (possibly disingenuous) sympathy for her, or the narrator's recognition that he's depicted a sad situation. [Hairy and Megan are talking] Megan: I worry that I'm just with you because it's familiar. Of course no one else compares. I've known you for so long that I'd have to spend years with someone to build up this kind of connection and I daren't let you go of you long enough to let that happen. Megan: But I guess this is really all I can ask for. I'm happy with you; I should stop worrying. [Megan takes Hairy's hand.] Hairy: This is probably a bad time to bring this up, but I don't actually like you. "
77
"Bored with the Internet"
"Bored with the Internet"
"https://www.xkcd.com/77"
"https://imgs.xkcd.com/comics/bored_with_the_internet.jpg"
"https://www.explainxkcd.com/wiki/index.php/77:_Bored_with_the_Internet"
"[Black Hat and Not-Hairy are talking in a room with a computer on.] Not-Hairy: I feel like I'm wasting my life on the internet. Let's walk around the world. Black Hat: Sounds good. [The two men are shown walking through trees.] [The two men are shown walking on flat stretch, with mountains in the distance.] [The two men are shown in a magnificent canyon. They stand, silently looking at the scene.] Not-Hairy: And yet all I can think is, "This will make for a great LiveJournal entry." "
"A character who has hair (not to be confused with Hairy ) suggests to Black Hat that he is wasting his life on the Internet, and they should go explore the world. They appear to walk a great distance, through what appears to be a swamp or perhaps a forest in winter, across a plain, and down to a river valley. Despite traveling so far and through such varied landscapes, in the last panel, Not-Hairy admits that all he can think about is what a great Livejournal post their trip would make. It appears that the plan to get the Internet off their mind has failed. Livejournal is a website on which users can make accounts and, effectively, blog, although the site is designed around the premise that the blogs ought to be used as personal journals, with the ability to privatize the journal or only let certain friends see certain entries. Livejournal was an early social network and an early blog platform, and was a good way for people to let others know what was going on in their lives. As of 2020, Livejournal still exists, although sites like Facebook and Twitter have become far more powerful and popular sites for sharing one's daily life. Unlike most of his appearances (especially later ones), Black Hat does not exhibit any of his signature Classhole tendencies. The title text suggests that Randall has overcome a tendency to think about how he will document what he has been doing, rather than concentrate on the thing itself. [Black Hat and Not-Hairy are talking in a room with a computer on.] Not-Hairy: I feel like I'm wasting my life on the internet. Let's walk around the world. Black Hat: Sounds good. [The two men are shown walking through trees.] [The two men are shown walking on flat stretch, with mountains in the distance.] [The two men are shown in a magnificent canyon. They stand, silently looking at the scene.] Not-Hairy: And yet all I can think is, "This will make for a great LiveJournal entry." "
78
"Garfield"
"Garfield"
"https://www.xkcd.com/78"
"https://imgs.xkcd.com/comics/garfield.jpg"
"https://www.explainxkcd.com/wiki/index.php/78:_Garfield"
"I want to see something unexpected in comics. Just one strip could make up for it all. [Garfield is standing on hind legs facing and looking directly at the camera. But is off-center in the frame, about 1/3 from the left, rotated very slightly clockwise.] [Zoom in on Garfield, still to the left, now rotated slightly counterclockwise.] [Zoom in again on Garfield, now the frame clips off the left side of his face.] Garfield thought bubble: The world is burning. [Final zoom in, the frame is ripped like a page, offset, and Garfield's eyes are half closed on the right half.] Garfield thought bubble: Run. Jim Davis, throw off your commercial shackles. Challenge us. Go out in a blaze of Dadaist glory. There is still time. "
"The newspaper comic strip Garfield , which features an orange cat as the main character, has increasingly been known for repetitive, quality-lacking strips. In the past, this was because the creator, Jim Davis , prefers to explore the same subjects he is comfortable with but in different ways — or from a less charitable view, because the strip is intended for a wide audience and thus becomes homogenized and inoffensive by nature. This attitude has only become more pronounced in the 21st century, as the aging Davis becomes less and less interested in the franchise. Regardless of the reason, these strips are now ghost written with little input from Davis and rarely explore the unconventional. The comic is challenging Davis to do something unexpected and surprise us all. The comic also accuses Davis of being a "sell out", sticking to bourgeois/commercial logic, something that dadaist artists challenged. Dadaism was an artistic movement in the early 20th century marked primarily by chaos, irrationality, and surrealism. Some of the artists believed that the bourgeois logic made human beings unhappy and therefore led to war. Randall leads by example by featuring a strip that parodies the style of Garfield, with multiple colors (xkcd usually contains only black and white, with some few containing an additional color like red or yellow) and a character that is not a stick figure breaking the normal xkcd pattern. Another dadaist aspect is the fact that while Garfield is smiling, he is communicating something that could be considered terrifying. The title text explains that xkcd is exercising legal use of Davis's intellectual property, namely the title character of his comic. The Supreme Court case mentioned, Campbell v. Acuff-Rose Music , confirmed that parody is legal even when there is commercial gain as a result, and also referenced the Copyright Act of 1976 , 17 U.S.C. § 107, for the same reason. While this is normally understood by most anyone who questions such matters, Randall includes it as a reference to the lessening of strict copyright law, which many comics also mention, usually in the context of open-source software and those who promote it, like at the comics featuring Richard Stallman . I want to see something unexpected in comics. Just one strip could make up for it all. [Garfield is standing on hind legs facing and looking directly at the camera. But is off-center in the frame, about 1/3 from the left, rotated very slightly clockwise.] [Zoom in on Garfield, still to the left, now rotated slightly counterclockwise.] [Zoom in again on Garfield, now the frame clips off the left side of his face.] Garfield thought bubble: The world is burning. [Final zoom in, the frame is ripped like a page, offset, and Garfield's eyes are half closed on the right half.] Garfield thought bubble: Run. Jim Davis, throw off your commercial shackles. Challenge us. Go out in a blaze of Dadaist glory. There is still time. "
79
"Iambic Pentameter"
"Iambic Pentameter"
"https://www.xkcd.com/79"
"https://imgs.xkcd.com/comics/iambic_pentameter.jpg"
"https://www.explainxkcd.com/wiki/index.php/79:_Iambic_Pentameter"
"[Two identical Cueballs are having a conversation. The latter is identified as Cueball, since he represents Randall who has the Hobby.] Friend: What time can you pick Michael up? Cueball: Well, I can meet the plane at ten of six. Friend: Do you know where to find him? Cueball: I'll meet him at the stairs before the gate. [Below the two Cueballs are the following text:] My hobby: answering casual questions in iambic pentameter. Iambs and other types of poetry " feet " are the subject of 1383: Magic Words . "
"In this part of the My Hobby series, the hobby is responding to casual questions using iambic pentameter . Iambic pentameter is a form of poetic verse defined by the number of syllables per line. In this form, a line contains exactly five (penta means five in Greek) " iambs " per line. An iamb is a unit of two syllables with the stress falling on the second. The actual breakup of the words is unimportant; the definition is based solely on the pattern of stressed and unstressed syllables. One line of strict iambic pentameter will have ten syllables, with the stress falling on the second, fourth, sixth, eighth, and last. In this comic, Cueball (i.e. Randall - the one with the hobby) is replying to his friend's questions. (The friend also looks like Cueball, but are here differentiated by who has the hobby.) Cueball's responses are each one line of iambic pentameter, just visually broken into two lines for space reasons. They read (adding the emphasis): "Well, I can meet the plane at ten of six " and "I'll meet him at the stairs be fore the gate " with a sort of bouncing rhythm. Shakespeare was one of the most famed users of iambic pentameter in his plays. This is the "strict form" of iambic pentameter. In practice, poets often strayed from the strict count of iambs as the image text suggests. Wikipedia offers two Shakespearian examples being "Now is the winter of our discontent," in which the first iamb is reversed ("Now" is stressed rather than "is"), and "To be or not to be, that is the question," which adds an extra unstressed syllable at the end. As the comic suggests in the title text, without such exceptions, it can be very difficult to stick to strict iambic pentameter for every sentence. [Two identical Cueballs are having a conversation. The latter is identified as Cueball, since he represents Randall who has the Hobby.] Friend: What time can you pick Michael up? Cueball: Well, I can meet the plane at ten of six. Friend: Do you know where to find him? Cueball: I'll meet him at the stairs before the gate. [Below the two Cueballs are the following text:] My hobby: answering casual questions in iambic pentameter. Iambs and other types of poetry " feet " are the subject of 1383: Magic Words . "
80
"My Other Car"
"My Other Car"
"https://www.xkcd.com/80"
"https://imgs.xkcd.com/comics/other_car.jpg"
"https://www.explainxkcd.com/wiki/index.php/80:_My_Other_Car"
"[The back of a blue Mitsubishi with a spoiler is shown.] Bumper sticker: This IS my other car. "
"This comic refers to a popular form of bumper sticker that follows the template "my other car is a ____." Sometimes the blank is a fancy vehicle like a Porsche or a Ferrari ; sometimes it's related to the person's job (e.g. "My other car is a fire truck"); sometimes it's an even more expensive form of transportation like a " yacht " or " private jet ," or even something joking or in fiction (like a " TARDIS "). The premise was to jokingly imply that someone driving in a less fancy vehicle was wealthier than they looked, as they could afford a fancy car (they simply chose to drive the clunker that day). The designer of the first stickers might even have intended them for serious use by wealthy drivers. The form of sticker ultimately became so well known that the phrase entered the pop-culture lexicon. Due to their popularity, these stickers also have been parodied in various ways, like the one Randall has invented here. Randall's sticker is a more "honest" sticker that admits "this IS my other car;" in other words, this is the nicer of the two cars. This sticker could probably be used on an expensive car to mirror the traditional sticker's use on a cheaper car. However, the car in the strip is a Mitsubishi, which is not a particularly expensive brand, though the presence of a spoiler indicates it may be one of the top-range models, or at least has had a little extra paid for some sports 'extras'. Thus it appears that Randall is using the sticker for contrasting purposes: while others would drive a modest car but joke that they have a really nice one at home, Randall's car is the one you see, and, as he noted in the title text, his other one is much worse than this one. It's also possible that this is a play on meta-levels; by definition, the car that you're driving can't be your other car, as it's your car you're driving now. Your other car is the one sitting at home. [The back of a blue Mitsubishi with a spoiler is shown.] Bumper sticker: This IS my other car. "
81
"Attention, shopper"
"Attention, shopper"
"https://www.xkcd.com/81"
"https://imgs.xkcd.com/comics/attention_shopper.jpg"
"https://www.explainxkcd.com/wiki/index.php/81:_Attention,_shopper"
"[Black Hat is holding a golf club and speaking into a P.A. system.] Black Hat: Attention, Black Hat: To the owner of a Dodge Viper SRT-10 with license plate "MYTOY," your lights are on and your windshield was just smashed with a golf club. "
"A common trope (often referenced in TV and film) is a loudspeaker announcement in which a store employee (or anyone else in charge somewhere where people gather, like church or a school) announces that a certain colour and model of car has its lights on, or is blocking another car, or is about to be towed, or similar. A licence plate is sometimes included to allow the owner to identify that it is specifically their car that is involved. In this case, Black Hat is up to his old ways as, in addition to announcing that an SRT-10 has its lights on, he also announces that it has had its windshield smashed with a golf club. Black Hat is, of course, holding a golf club, frustrated at the owner’s revolting arrogance. The lights are probably on because the attack triggered the car's alarm system. The Dodge Viper SRT-10 was a version of the Dodge Viper available on the third and fourth generations of Viper from 2003-2010. It was a very expensive sports car. The two license plates in the comic are personalized license plates. The one in the comic-proper is clearly "My Toy"; the plate in the title text is most likely "Dad's Money," which Randall suggests is a real plate on a car outside his building, suggesting that the driver's father paid for the car, bragging about how rich their family is. This car will likely also soon earn Black Hat’s wrath. [Black Hat is holding a golf club and speaking into a P.A. system.] Black Hat: Attention, Black Hat: To the owner of a Dodge Viper SRT-10 with license plate "MYTOY," your lights are on and your windshield was just smashed with a golf club. "
82
"Frame"
"Frame"
"https://www.xkcd.com/82"
"https://imgs.xkcd.com/comics/frame.jpg"
"https://www.explainxkcd.com/wiki/index.php/82:_Frame"
"[Cueball stands alone in the center of this almost normally framed panel. But there are four small indentations two both left and right and maybe also one top right.] [Tendrils from the frame develop and grow inwards while breaking the outer frame down. The tendrils comes close to Cueball. There are 13, three from three of the four sides and four from the right.] [The tendrils have now completely broken the outer frame down and 11 have reached Cueball and these begins to wind themselves around him. There are tendrils around his forehead, neck, cheek, left arm, left wrist, left hand, right wrist, right hand, lower torso, left leg and right leg. Those around his legs spiraling almost up to his crotch. 14 other tendrils have not reached him yet. All those reaching him was among the 13 from the previous panel. Only the two from the bottom right corner did not make contact. The other 12 not reaching him where new.] [Finally the 11 tendrils that have reached Cueball retract along with the other 14 tendrils back to the frame, tearing Cueball apart in 9 pieces, leaving one central piece (his upper torso with a part of each arm) floating in the center without tendrils on it. His head has been split in two by three tendrils, that keep the parts close together. The left arm with one tendril has been split from the hand with two tendrils, whereas the two holding the wrist and hand kept their part of the arm in one piece. The two legs have been separated from the lower torso at the crotch, and they as well as the lower torso is all being pulled away by one tendril. The other tendrils have almost reached the frame, three of them are already gone leaving 11 near the frame. The frame has also nearly reformed it self again.] "
"Cueball is standing in the middle of the first square panel, but then the panel's frame starts warping away from being square and starts to form into tendrils that move toward him, then slowly wrap themselves around him, and finally retract, reforming the frame again, but pulling him apart in the process, in a rather macabre comic. Typically, the frame on a cartoon is used to separate different periods of the action. Here, this has been subverted by the frame becoming a character, the main protagonist, and sole survivor of the strip. There is some indication that Cueball is also just part of a drawing, since his upper torso, with parts of each arm, is left hanging in the air without any tendrils touching it. If it was not stuck in the center of the image, it would fall down, but more importantly, even if all tendrils pulled very fast at the same time, it is highly unlikely that they could pull so precisely that the body would split in four pieces around this remaining body cross, and one of the tendrils should have pulled this part along with either an arm, the head, or the lower torso. This could be some comfort for those who think that this is too much. Of course, it could also just be something that Randall did not think was important in such a surreal comic. Comics often use artifacts on the frame to add mood to the comic. This comic then makes those artifacts a major feature of the comic, like a Chekhov's gun ("If you say in the first chapter that there is a rifle hanging on the wall, in the second or third chapter it absolutely must go off.") The use of creative panel layouts and effects was first made possible in newspaper comics at the insistence of Bill Watterson, author of Calvin and Hobbes (which it is known that Randall has been influenced by), requiring lengthy negotiations due to the printing technology of the time. The creative use of panel layout and effects is thus part of the artistic legacy of Calvin and Hobbes. xkcd, among others, has continued along that path of pushing the boundaries of the medium. The title text "..." could indicate that Randall wasn't being very serious about this comic. But perhaps it was an idea to creatively use parts of the comic nobody thought about, and it spoke for itself and needed no extra comment. The three dots also indicate that something more will happen soon. The reader may visualize the final result and empty square panel, ready for the next unfortunate person to walk into this trap. Alternatively, it could mean that Randall found the comic so bizarre, even he couldn't comment on it (see Trivia section ). [Cueball stands alone in the center of this almost normally framed panel. But there are four small indentations two both left and right and maybe also one top right.] [Tendrils from the frame develop and grow inwards while breaking the outer frame down. The tendrils comes close to Cueball. There are 13, three from three of the four sides and four from the right.] [The tendrils have now completely broken the outer frame down and 11 have reached Cueball and these begins to wind themselves around him. There are tendrils around his forehead, neck, cheek, left arm, left wrist, left hand, right wrist, right hand, lower torso, left leg and right leg. Those around his legs spiraling almost up to his crotch. 14 other tendrils have not reached him yet. All those reaching him was among the 13 from the previous panel. Only the two from the bottom right corner did not make contact. The other 12 not reaching him where new.] [Finally the 11 tendrils that have reached Cueball retract along with the other 14 tendrils back to the frame, tearing Cueball apart in 9 pieces, leaving one central piece (his upper torso with a part of each arm) floating in the center without tendrils on it. His head has been split in two by three tendrils, that keep the parts close together. The left arm with one tendril has been split from the hand with two tendrils, whereas the two holding the wrist and hand kept their part of the arm in one piece. The two legs have been separated from the lower torso at the crotch, and they as well as the lower torso is all being pulled away by one tendril. The other tendrils have almost reached the frame, three of them are already gone leaving 11 near the frame. The frame has also nearly reformed it self again.] "
83
"Katamari"
"Katamari"
"https://www.xkcd.com/83"
"https://imgs.xkcd.com/comics/katamari.jpg"
"https://www.explainxkcd.com/wiki/index.php/83:_Katamari"
"[Megan stands on the left. Cueball is sitting on the floor with a game controller in his hand. He is looking at a TV on the floor connected to a game console, also on the floor.] Megan: Can you pause for a moment and help me with something? Cueball: You know, our love is like a katamari. We travel along, rolling up more and more of the world into our shared experience, taking it and making it our own. Megan: I, you... wow. Geekiness aside, that was actually incredibly sweet. Cueball: The clutter of everyday life, with a simple core to tie it together, eventually becomes something grand as the world itself. [A rainbow extends outward from the TV, with "ROYAL RAINBOW!" above it. Cueball raises his hands in victory.] Megan: Okay, also sweet, but now I'm wondering if you could possibly get any gayer. Katamari Damacy is also a subject of 161: Accident and 851: Na . "
"Katamari Damacy is a Japanese game in which the player must roll around an infinitely sticky katamari ball, cottoning up objects and terrain to increase the ball's size. In this comic, Cueball uses the katamari as an analogy for his love for Megan , pushing it to such embarrassing extremes that Megan feels the need to remark whether he could "possibly get any gayer." At this point, Cueball wins the level he is playing and is transported by a "Royal Rainbow," an in-game occurrence at the completion of each level. The rainbow is a symbol of gay pride, in addition to being just a generally happy (i.e. gay) idea. Cueball also only takes up such a stand after Megan requests that he help her. This is possibly a criticism of male selfishness (perhaps Randall's self-criticism), in that males do not discuss romantic ideas, except as a way out. The King of All Cosmos , mentioned in the title text, is an instructive character in all of the Katamari games. The title text points out that perhaps we either like or love video games not because they are fun, but because they let us forget our problems and retreat into someone else or an intricate fantasy. [Megan stands on the left. Cueball is sitting on the floor with a game controller in his hand. He is looking at a TV on the floor connected to a game console, also on the floor.] Megan: Can you pause for a moment and help me with something? Cueball: You know, our love is like a katamari. We travel along, rolling up more and more of the world into our shared experience, taking it and making it our own. Megan: I, you... wow. Geekiness aside, that was actually incredibly sweet. Cueball: The clutter of everyday life, with a simple core to tie it together, eventually becomes something grand as the world itself. [A rainbow extends outward from the TV, with "ROYAL RAINBOW!" above it. Cueball raises his hands in victory.] Megan: Okay, also sweet, but now I'm wondering if you could possibly get any gayer. Katamari Damacy is also a subject of 161: Accident and 851: Na . "
84
"National Language"
"National Language"
"https://www.xkcd.com/84"
"https://imgs.xkcd.com/comics/national_language.jpg"
"https://www.explainxkcd.com/wiki/index.php/84:_National_Language"
"[Caption on top:] This happened to my friend: [Three men and two women are standing in a row.] Cueball: English should be the national language. These immigrants should have to learn English when they come here. Megan: Yeah. Cueball: When you go to live somewhere, you learn the language they speak there. Cueball: English is the language of the land. Ponytail: Excuse me, but osio Sarah dawado. Cueball: What the hell was that? Ponytail: Cherokee. "
"This comic is about the concept of nativism , which is the view that those who are native to a place should have more rights than immigrants. A frequently expressed view in the U.S. (and in other countries) is that immigrants should learn English, which is the primary language in the United States. In the comic, one character is arrogantly arguing the nativist position. However, the woman next to him interrupts him and says a phrase in the Cherokee language - "Hello, my name is Sarah" - which is an Iroquoian language used by the Cherokee Native American people. Although Cherokee seems to be a relatively young culture , it is much more native to America than any European culture, such as English. The woman is therefore effectively suggesting a "what's good for the goose is good for the gander" argument, that if the Europeans did not have to learn the native language, why should current immigrants learn English? She points out that even the English speakers are immigrants who did not learn the native language. Alternatively, she is saying that the term "national language" has no clear meaning, especially in the United States, where there is no official language; therefore, the "language they speak there" can be any of the languages spoken in the country: English, Spanish, German, Cantonese, or Cherokee, to name a few. The title text reveals that Ponytail is in fact Randall's friend; in the comic it is unclear who his friend is. [Caption on top:] This happened to my friend: [Three men and two women are standing in a row.] Cueball: English should be the national language. These immigrants should have to learn English when they come here. Megan: Yeah. Cueball: When you go to live somewhere, you learn the language they speak there. Cueball: English is the language of the land. Ponytail: Excuse me, but osio Sarah dawado. Cueball: What the hell was that? Ponytail: Cherokee. "
85
"Paths"
"Paths"
"https://www.xkcd.com/85"
"https://imgs.xkcd.com/comics/paths.jpg"
"https://www.explainxkcd.com/wiki/index.php/85:_Paths"
"[Blueprint of a campus. Two buildings in the upper and lower left corners, respectively, and a rectangular lawn. A road encloses the lawn, another road traverses horizontally through the center of the lawn. The character is in the lower left and the upper right corner, where it says "my apartment".] [Dashed line 1, from the lower-left along the road to the top-left corner, then to the top-right corner.] 60 seconds [Dashed line 2, from the lower-left along the road up to the center crossroads, then diagonally over the lawn to the top-right corner.] 48 seconds (80%) [Dashed line 3, diagonally from the lower-left to the top-right corner.] 44.7 seconds (74%) My apartment 1=t 2=(t*(1+√2))/3 3=(t*√5)/3 When I'm walking, I worry a lot about the efficiency of my path. "
"This comic centers around the consideration of what is the shortest path available to a person traveling by foot. Cueball has to travel across a rectangular distance, which has an established path around the periphery. When Cueball follows these paths, he has to walk for 60 seconds. He realizes that by ignoring the paths and taking the desire lines from corner to corner, his route will be shorter, and he calculates that he could cut up to 26% of his time. As a result, every time he has to travel this rectangle, he worries about the extra time taken as a result of following the path. There are downfalls to this plan, however. This is convenient for Cueball but probably not for the building owner, as many rectangular lawns have delicate decorations such as flowers on them. [Blueprint of a campus. Two buildings in the upper and lower left corners, respectively, and a rectangular lawn. A road encloses the lawn, another road traverses horizontally through the center of the lawn. The character is in the lower left and the upper right corner, where it says "my apartment".] [Dashed line 1, from the lower-left along the road to the top-left corner, then to the top-right corner.] 60 seconds [Dashed line 2, from the lower-left along the road up to the center crossroads, then diagonally over the lawn to the top-right corner.] 48 seconds (80%) [Dashed line 3, diagonally from the lower-left to the top-right corner.] 44.7 seconds (74%) My apartment 1=t 2=(t*(1+√2))/3 3=(t*√5)/3 When I'm walking, I worry a lot about the efficiency of my path. "
86
"Digital Rights Management"
"Digital Rights Management"
"https://www.xkcd.com/86"
"https://imgs.xkcd.com/comics/sony_microsoft_mpaa_riaa_apple.jpg"
"https://www.explainxkcd.com/wiki/index.php/86:_Digital_Rights_Management"
"[Black Hat is standing on an advancing glacier] Black Hat: Dear Sony, Microsoft, the MPAA, the RIAA, and Apple: Let's make a deal. You stop trying to tell me where, when, and how I play my movies and music, and I won't crush your homes under my inexorably advancing wall of ice. There appears to be a larger version of Black Hat, drawn in pencil and erased, behind him. The smaller figure makes the inexorably advancing wall of ice appear correspondingly larger. "
"Digital rights management (DRM) is a class of methods for controlling digital files, such as by preventing media from playing on any device besides the device from which the purchase is made. It is used by several major companies, as it makes it more difficult to pirate media, which they claim cuts into their profits. Those companies typically also lobby for laws forbidding circumvention of DRM techniques, like the Digital Millennium Copyright Act (DMCA). However, DRM is usually disliked by consumers, as it makes it difficult to use their purchased media. For example, if they buy a new computer, there's no guarantee that their DRM-covered media will be usable on the new computer. Thus, Black Hat is suggesting to the pro-DRM organizations Sony , Microsoft , the Motion Picture Association of America (MPAA), the Recording Industry Association of America (RIAA), and Apple that they stop their DRM-fiddling and lobbying, and he'll stop his inexorable ice-wall. The title text refers readers to law professor Lawrence Lessig 's book Free Culture . [Black Hat is standing on an advancing glacier] Black Hat: Dear Sony, Microsoft, the MPAA, the RIAA, and Apple: Let's make a deal. You stop trying to tell me where, when, and how I play my movies and music, and I won't crush your homes under my inexorably advancing wall of ice. There appears to be a larger version of Black Hat, drawn in pencil and erased, behind him. The smaller figure makes the inexorably advancing wall of ice appear correspondingly larger. "
87
"Velociraptors"
"Velociraptors"
"https://www.xkcd.com/87"
"https://imgs.xkcd.com/comics/velociraptors.jpg"
"https://www.explainxkcd.com/wiki/index.php/87:_Velociraptors"
"[Picture of a suburban house, with lines pointing to various aspects.] High bathroom window: probably secure. Outer door: secure. Picture window: VELOCIRAPTOR ENTRY POINT! It's been over a decade since Jurassic Park opened, and I still size up buildings for their potential as shelter against Velociraptor attacks. This comic marks the first reference in xkcd to Jurassic Park , and specifically to Randall 's fear of velociraptors . The fear will continue to be a subject of future comics and running jokes. "
"This comic refers to the film Jurassic Park , a 1993 movie based on the 1990 novel by Michael Crichton . The film depicts a billionaire who buys an island and opens a zoo/theme park for dinosaurs cloned from DNA recovered from blood found in fossilized mosquitoes. Naturally, everything goes haywire, and several of the creatures, among which are the velociraptors subject of this comic, try to devour every human in the theme park. Velociraptors (often shortened as " raptors ") are a species of relatively small, carnivorous dinosaur that play a central role in the original film and its sequels. In the film, packs of Velociraptors attack the main characters at various points, even entering buildings; they play a large role in the climax of the film. According to Wikipedia, the velociraptors in the film were erroneously based on Deinonychus . The movie depicts the velociraptors as having scaly reptilian skin, though dinosaurs of this type are now theorized to have been feathered. As we see in this comic, and will see in future comics, even though it had been approximately thirteen years since he presumably first saw the film, Randall apparently has lived in perpetual fear of a real raptor attack. Specifically, in this comic, he worries how a building would stand up against the creatures. The main risk posed by the house depicted comes by the large window in the living room, through which a Velociraptor could break-and-enter (believing that the bathroom window is too high for them to reach, and the door too secure to break through). The image text points out what he presumes is the reader's disbelief that Jurassic Park had (as of 2006) been released so long ago (thirteen years prior). This is another classic xkcd premise that will later be the subject of 891: Movie Ages five years later, which includes Jurassic Park again. This is the first in a long line of comments and comics Randall has made about how realizing the release dates of things in popular culture can make us feel old. [Picture of a suburban house, with lines pointing to various aspects.] High bathroom window: probably secure. Outer door: secure. Picture window: VELOCIRAPTOR ENTRY POINT! It's been over a decade since Jurassic Park opened, and I still size up buildings for their potential as shelter against Velociraptor attacks. This comic marks the first reference in xkcd to Jurassic Park , and specifically to Randall 's fear of velociraptors . The fear will continue to be a subject of future comics and running jokes. "
88
"Escher Bracelet"
"Escher Bracelet"
"https://www.xkcd.com/88"
"https://imgs.xkcd.com/comics/escher_wristband.jpg"
"https://www.explainxkcd.com/wiki/index.php/88:_Escher_Bracelet"
"[A Livestrong-type bracelet is featured, but with an Escher twist in it. The band is a Mobius strip. The band has the letters "WWED" printed on it.] What Would Escher Do? "
"This image parodies "WWJD" bracelets, which is an acronym for "What Would Jesus Do?". Christians (primarily) wear such bracelets (or other "WWJD" paraphernalia) as a reminder to act in a way that Jesus would act, which presumably is the "Christian" way to act. It is not entirely clear, but this particular bracelet appears to be the rubber type most famously popularized by the yellow ones of cyclist Lance Armstrong's Livestrong charity, which later became a popular fad for all sorts of charitable and non-charitable causes. In this comic, the "J" has been replaced by an "E" for M. C. Escher , a Dutch graphic artist (1898–1972) best known for art containing imagery that would be impossible in the real world (often referred to as impossible constructions or optical illusions). Among his most famous works are " Drawing Hands " – two hands drawing each other on paper; " Relativity ", in which a series of staircases and arches come from the floor, ceiling, and the walls in all directions, each with people standing on them as if each direction is "down"; and " Ascending and Descending " – a building with a staircase on its roof that is a closed square that appears to ascend or descend infinitely, depending on the direction that is walked. In keeping with Escher's art, the WWED bracelet has a single half-twist in it, creating what is known as a Mobius strip . Although this is not an impossible construction, it is still an apparently confusing structure that Escher used in his art. Most notably, his work "Mobius Strip II" depicts ants crawling around a Mobius strip. One can create this shape simply by taking a strip of paper (or any bendable material), making a half twist, and attaching the ends together. If you draw a single continuous line starting down the centre of the bracelet from the middle of the "W" going left, you will end up drawing from the "WWED", going around again on the "inside" of the bracelet, before coming back around to the front again and ending up at the "D". In other words, the surface of the bracelet has only one side (the front and the back are the same side). The phrase "the only downside" in the image-text may be a pun referencing this one-sidedness. As the title text suggests, the twist in the bracelet might make it uncomfortable to wear. [A Livestrong-type bracelet is featured, but with an Escher twist in it. The band is a Mobius strip. The band has the letters "WWED" printed on it.] What Would Escher Do? "
89
"Gravitational Mass"
"Gravitational Mass"
"https://www.xkcd.com/89"
"https://imgs.xkcd.com/comics/gravitational_mass.jpg"
"https://www.explainxkcd.com/wiki/index.php/89:_Gravitational_Mass"
"[Black Hat standing.] Black Hat: Gravitational mass is identical to inertial mass. That is, the amount of inertia something has and the amount of gravity it has are effectively the same. What's interesting is that there doesn't seem to be any reason this should be true. One could imagine an extremely large object with lots of resistance to force and no gravity (or vice versa), but this is never observed. [Black Hat still standing. The panel is now shorter.] Black Hat: You know what? I'm just gonna skip the rest of the buildup and say it: Yo mama's fat."
"Black Hat launches into what appears to be an in-depth exposition about the relativity of gravity and inertia. However, it transpires that this is just a convoluted build-up to a Yo' Momma joke along the lines of "she's fat and not that attractive." Black Hat then can't be bothered with, or can't figure out, the lengthy route to his punchline, so just goes for a straightforward insult instead. A well known joke format goes: "Yo' momma's so fat, when she X, she Y." For example: "Yo' momma's so fat, when she sits around the house, she sits around the house!" Variations play with the format, for example: "Yo' momma's so fat, she fell in the Grand Canyon and got stuck!" A "Yo' Momma" joke also appears in comic 681: Gravity Wells to the right of Jupiter. The title text is a play on the law of gravitational attraction, which diminishes as the square of the distance, so if the distance between two objects doubles, the attraction is reduced to a quarter, and if the distance is halved, the attraction quadruples. Black Hat is saying that the attraction goes up as the cube, so if the distance is halved, the attraction increases eight-fold, and decreases eight-fold when the distance doubles. This implies that "your momma is so fat, she breaks the laws of physics (and does so in a way that she isn't as attractive as physics would dictate, given enough distance)." The title text is slightly ambiguous; it seems to say that as distance increases, the attraction increases, but it doesn't explicitly state whether the distance is increasing or decreasing. Note: Contrary to Black Hat's explanation, and as per Albert Einstein's theory of general relativity , the reason that objects have equal gravitational and inertial mass is that anything with mass or energy causes a warping of space-time that causes all other objects (including such objects that classically shouldn't be affected, like photons) to experience the same gravitational acceleration. [Black Hat standing.] Black Hat: Gravitational mass is identical to inertial mass. That is, the amount of inertia something has and the amount of gravity it has are effectively the same. What's interesting is that there doesn't seem to be any reason this should be true. One could imagine an extremely large object with lots of resistance to force and no gravity (or vice versa), but this is never observed. [Black Hat still standing. The panel is now shorter.] Black Hat: You know what? I'm just gonna skip the rest of the buildup and say it: Yo mama's fat."
90
"Jacket"
"Jacket"
"https://www.xkcd.com/90"
"https://imgs.xkcd.com/comics/jacket.jpg"
"https://www.explainxkcd.com/wiki/index.php/90:_Jacket"
"[Two men stand and talk to one another.] Cueball: Where's my fucking jacket? [Friend indicates something behind him.] Friend: Over there, next to your regular one. Cueball: My what? Friend: Never mind. This comic is the second comic to use an all-caps lettering, the first being 78: Garfield , where the all-caps lettering may have been based off of the lettering in the actual comic strip. "
"Cueball clearly means to use fucking as an intensifier. However, the friend (likely intentionally in response to the unnecessary swearing) takes fucking to be an identifier of which jacket is being discussed, and gives a smart-aleck response. His counterpart gets confused by the sarcasm, and the topic is dismissed. The title text states that this often occurs in Cueball/Randall's apartment. [Two men stand and talk to one another.] Cueball: Where's my fucking jacket? [Friend indicates something behind him.] Friend: Over there, next to your regular one. Cueball: My what? Friend: Never mind. This comic is the second comic to use an all-caps lettering, the first being 78: Garfield , where the all-caps lettering may have been based off of the lettering in the actual comic strip. "
91
"Pwned"
"Pwned"
"https://www.xkcd.com/91"
"https://imgs.xkcd.com/comics/pwned.png"
"https://www.explainxkcd.com/wiki/index.php/91:_Pwned"
"Welcome to text-only Counterstrike. You are in a dark, outdoor map. > GO NORTH You have been pwned by a grue. "
"In the days of early personal computers, such as the IBM-XT, Atari, or C64, games were largely text-based adventure games . Those games were based on an interactive story, and the player had to solve a puzzle on this by communicating to the application using only a keyboard or, later, a mouse. Play was turn-based (like chess): the computer displayed some textual context, you entered a command (GO <direction>, TAKE <object>, KILL <person>, LOOK AT <object>, etc.), and the computer responded by giving the outcome of your command. This sparse context arose from the fact that games in the 1970s and 1980s needed to run on limited memory and microprocessor capacity, and on basic displays. Over the following 20 years, technical advances allowed games to run in a real-time graphical context. Adventure games were largely displaced by other genres, including Role Playing Games (RPG) , where the player navigates a character through a graphical environment to achieve goals or gain in abilities, often involving a combat component. While the broad structure of these has a lot of similarity to adventure games, the experience is very different. Zork is a classic example of a text-adventure game franchise. In the Zork games, players have to evade predators known as grues, which fear light, but love to devour adventurers entering the dark. Therefore, you cannot win the game without owning some light source. "Counterstrike" is a reference to the Half-Life mod Counter-Strike and its subsequent sequel. In the Counter-Strike series, you are either a terrorist or a counter-terrorist operative, and your goal is to stop the other from completing their objective. On a dark map, players would generally use night vision goggles, which don't produce light that would give away their position to the enemy. Randall imagines a version of Counterstrike played in the text-context of Zork. Ironically, the outcome is not so different to what might be a typical experience of Counterstrike gameplay, particularly for inexperienced players: on starting the game, the player moves to another room and is immediately " pwned " (a typical online gaming term meaning beaten, killed, or trapped/tricked) by an enemy. In the title text, Randall suggests that a comparison of the genres, analyzing the reasons why RPGs have proved more popular, would make an interesting study. His imagined example suggests that what has been gained in immersive environments may have been lost in complexity of story and gameplay. Welcome to text-only Counterstrike. You are in a dark, outdoor map. > GO NORTH You have been pwned by a grue. "
92
"Sunrise"
"Sunrise"
"https://www.xkcd.com/92"
"https://imgs.xkcd.com/comics/sunrise.jpg"
"https://www.explainxkcd.com/wiki/index.php/92:_Sunrise"
"[Hairy is on the street. Behind him is a house with a lawn.] Hairy (thinking): I love the time just before sunrise. It's quiet; no one is ever just walking about. Hairy (thinking): It's like a secret Hairy (thinking): I always hope that I'll find someone else quietly hiding from sleep, and we'll see each other and sit and talk. Hairy (thinking): I guess this is a bad place to meet people. Hairy (thinking): I wish it weren't. [Hairy goes into the house, brushes his teeth, shaves his head (?), and leaves the house again.] [Hairy is at a club, disco balls in the ceiling and a giant woofer. Many people are dancing around him.] "
"This comic is about the desire for an intimate connection with another, and the compromises we make to not be alone. Hairy finds a certain beauty in the way the world looks without billions of humans crawling around on it. He thinks of this as a secret place that thrills him. He is excited about the remote chance of finding someone like him who appreciates its beauty. But he realizes that it's the very thing that makes this time beautiful to him that makes his imagined chance encounter exceedingly unlikely. Reconciled to the fact that he will not find a kindred spirit outside this morning, he heads back home. At the house, he gets ready and drives to a club to meet people. The club is drawn using an inverted color scheme (white people, black background) to emphasize that it is the opposite of the 4am outside world. The club is dark and full of people, who are the lightest things present, where outside, the natural beauty shines without interruption by human forms. Hairy is seen alone in the middle of the crowd. The title text is a reference to a common music video scene (sometimes country music videos) where people play the guitar on parking garages as the sun rises. [Hairy is on the street. Behind him is a house with a lawn.] Hairy (thinking): I love the time just before sunrise. It's quiet; no one is ever just walking about. Hairy (thinking): It's like a secret Hairy (thinking): I always hope that I'll find someone else quietly hiding from sleep, and we'll see each other and sit and talk. Hairy (thinking): I guess this is a bad place to meet people. Hairy (thinking): I wish it weren't. [Hairy goes into the house, brushes his teeth, shaves his head (?), and leaves the house again.] [Hairy is at a club, disco balls in the ceiling and a giant woofer. Many people are dancing around him.] "
93
"Jeremy Irons"
"Jeremy Irons"
"https://www.xkcd.com/93"
"https://imgs.xkcd.com/comics/jeremy_irons.jpg"
"https://www.explainxkcd.com/wiki/index.php/93:_Jeremy_Irons"
"[Cueball points at Megan with his mouth open. Jeremy Irons stands behind him.] Jeremy Irons: But as THICK as you are, pay attention Jeremy Irons: My words are a matter of PRIDE! My goal: To make enough money to hire Jeremy Irons, the voice of Scar from The Lion King , to follow me around and do my dialogue. "
"Similar to the " My Hobby " series, this comic depicts one of Randall 's goals in life: He wants to hire Academy-Award-winning actor Jeremy Irons to deliver all of Randall's dialogue in life (while Randall, perhaps, lip syncs it). He is apparently basing this desire on the fact that Irons, a classically trained English actor, portrayed Scar, the main antagonist in the 1994 Disney animated feature The Lion King . The line spoken in the comic is from the song " Be Prepared ", which Scar sings in the film. Thus, it's not entirely clear whether Randall enjoys Irons's deep, rumbling British-accented voice, or whether it's Scar's dialogue in the film that Randall truly would like to be speaking. The title text suggests that Randall knows the dialogue of The Lion King from memory; it also suggests that there are others he knows as well. He is around the appropriate age to have been in the target market for the film (he would have been around 10 at the time) and probably saw it many times. [Cueball points at Megan with his mouth open. Jeremy Irons stands behind him.] Jeremy Irons: But as THICK as you are, pay attention Jeremy Irons: My words are a matter of PRIDE! My goal: To make enough money to hire Jeremy Irons, the voice of Scar from The Lion King , to follow me around and do my dialogue. "
94
"Profile Creation Flowchart"
"Profile Creation Flowchart"
"https://www.xkcd.com/94"
"https://imgs.xkcd.com/comics/profile_flowchart.jpg"
"https://www.explainxkcd.com/wiki/index.php/94:_Profile_Creation_Flowchart"
"[A flowchart is shown.] Have Friends? → No → Link to your LiveJournal Have Friends? → Yes, and want to alienate everyone else → Inside jokes! Have Friends? → Yes → Have Boyfriend/ Girlfriend? → No → Angsty about it? → Yes → Link to your LiveJournal No → Yes you are → Angsty about it? Yes → A profile tribute is the greatest possible expression of love. "
"AIM (short for AOL Instant Messenger, now defunct) offered its users profile pages to share info about themselves or their friends. Randall notes that these pages fall into one of three categories: Both AIM and LiveJournal were known for their teenage user base, as shown by the title text's fictional AIM screen name. The title text seems to reference the kind of behavior someone with a tribute page would display, but is actually an example of an inside joke, for cartoonists. The text comes from Natalie Dee Comic 956, from January 8, 2006 , a few months before this XKCD comic was published on April 26 of the same year. [A flowchart is shown.] Have Friends? → No → Link to your LiveJournal Have Friends? → Yes, and want to alienate everyone else → Inside jokes! Have Friends? → Yes → Have Boyfriend/ Girlfriend? → No → Angsty about it? → Yes → Link to your LiveJournal No → Yes you are → Angsty about it? Yes → A profile tribute is the greatest possible expression of love. "
95
"The Sierpinski Penis Game"
"The Sierpinski Penis Game"
"https://www.xkcd.com/95"
"https://imgs.xkcd.com/comics/the_sierpinski_penis_game.jpg"
"https://www.explainxkcd.com/wiki/index.php/95:_The_Sierpinski_Penis_Game"
"[A large triangle, point down, is shown, with many smaller triangles inside all pointing up. There is one large triangle in the middle, with 3 medium triangles on either side and three triangles on either of their sides as well, for a total of 9. This trend then continues three more times, with 27 around the nine and 81 around those. Finally, there were supposed to be 243 (3x81) very small filling out all the space outside the larger triangles, but staying inside the original triangle. But there seem to be missing three of these near the top. Two of those are on either side of the first (top left) of the nine triangles of size 3, as well as one to the left of the top of the top right second largest triangle. But there is also one extra triangle just below the P in the bottom triangle with a sentence. That would have been the first of the next level of 3*243=729 triangles in level 7. But it is the only one. So 240 small triangles plus 1 even tinier for a total of 362 inside the largest framing triangle.] [There is a word inside the largest of the triangles and a sentence in the largest triangle below that triangle.] Penis! Haha, penis. "
"The Chaos Game is a method of generating a fractal by repeatedly applying randomly-chosen transformation functions to a point and plotting the position of the new point each time. The transformation functions are randomly chosen from a small, predefined list. The surprising result of this is that, even though the functions are picked randomly, a distinctly non-random fractal image emerges. The exact nature of this image depends on the list of transformation functions used. One such fractal that can be produced by the Chaos Game is the Sierpinski Triangle , which is the fractal pictured in this comic. See details in this video . The Penis Game, on the other hand, is a childish activity where people (usually schoolchildren) compete to shout "Penis!" increasingly loudly in the presence of an authority figure (usually a teacher) without getting in trouble. The two games could be said to be similar in that they both involve iterations of transformations; in the Chaos Game, a point's position is transformed (moving it closer and closer to the attractor set of the transformations); in the Penis game, the volume of the phrase "Penis!" is transformed (becoming louder and louder). The difference is that the Chaos Game works by negative feedback (eventually settling down into a well-defined image) whereas the Penis Game involves positive feedback (at some point, the cry of "Penis!" will become loud enough that the culprit will get in trouble and the game will end). Nonetheless, they could be vaguely considered inverses of each other, and Randall appears to be conflating the two in this comic. The title text mentions two inappropriate places to play the Penis Game. A baby shower is supposed to be a celebration of childbirth or pregnancy, so it would be an inappropriate place for such crude humor. A terrorist attack is typically a time in which lives are lost, so it would be very immature to play such a crude game. The title text may also be calling attention to the fact that a mathematical object such as a fractal is also an inappropriate place in which to be playing the Penis Game. [A large triangle, point down, is shown, with many smaller triangles inside all pointing up. There is one large triangle in the middle, with 3 medium triangles on either side and three triangles on either of their sides as well, for a total of 9. This trend then continues three more times, with 27 around the nine and 81 around those. Finally, there were supposed to be 243 (3x81) very small filling out all the space outside the larger triangles, but staying inside the original triangle. But there seem to be missing three of these near the top. Two of those are on either side of the first (top left) of the nine triangles of size 3, as well as one to the left of the top of the top right second largest triangle. But there is also one extra triangle just below the P in the bottom triangle with a sentence. That would have been the first of the next level of 3*243=729 triangles in level 7. But it is the only one. So 240 small triangles plus 1 even tinier for a total of 362 inside the largest framing triangle.] [There is a word inside the largest of the triangles and a sentence in the largest triangle below that triangle.] Penis! Haha, penis. "
96
"Mail"
"Mail"
"https://www.xkcd.com/96"
"https://imgs.xkcd.com/comics/mail.png"
"https://www.explainxkcd.com/wiki/index.php/96:_Mail"
"[Cueball is talking to someone through a phone.] Phone: Do you think I could mail a running chainsaw to someone? Cueball: I doubt it Phone: What about a baby's first word? Cueball: Look, your obsession with sending strange things through the mail is getting out of hand. Phone: Can you mail a blank stare? Phone: A dizzying height? Phone: Pi? Cueball: ... Phone: Well, did you at least get that package of time I sent you? Cueball: I... you... no, I didn't. Phone: Well, there was a lot of it, so it will probably take a while "
"Cueball 's interlocutor is working their way through a list of increasingly impractical or impossible suggestions for things to send through postal mail. The pay-off is that they have already somehow sent a package of time through the mail, and this is taking a while to arrive, presumably because the amount of time it will take to reach the recipient is equal to the amount of time being sent. By the time it reaches Cueball, the time will have passed, and therefore not be of much use. The reference to a 'package of time' could refer to quantizing time ("discrete packets of time") - a theory that time is not continuous as particles in the quantum mechanics . It could be one of the big mistakes in modern science, but feels as if there's more to it, in the world of romance, sarcasm, math, and language. A no-fly list is a list of people who are not allowed to use commercial airlines for travel. In the United States, it is maintained by the Terrorist Screening Center . According to the title text, the person sending strange objects through mail is on a no-fly list for the United States Postal Service (USPS). While the USPS has a list of items banned from being shipped in the mail, which includes most consumer electronics with lithium batteries, it does not have such a list for people. This could suggest that this person has attempted to send so many strange items that USPS will no longer accept mail from him, or it could imply that they attempted, at one point, to send themselves via air mail, and have been banned from doing so again. This comic might be related to W. Reginald Bray , an Englishman from the turn of the 20th century, who was famous for mailing unusual objects (including himself) to experiment with the postal system. A list of the things: [Cueball is talking to someone through a phone.] Phone: Do you think I could mail a running chainsaw to someone? Cueball: I doubt it Phone: What about a baby's first word? Cueball: Look, your obsession with sending strange things through the mail is getting out of hand. Phone: Can you mail a blank stare? Phone: A dizzying height? Phone: Pi? Cueball: ... Phone: Well, did you at least get that package of time I sent you? Cueball: I... you... no, I didn't. Phone: Well, there was a lot of it, so it will probably take a while "
97
"A Simple Plan"
"A Simple Plan"
"https://www.xkcd.com/97"
"https://imgs.xkcd.com/comics/a_simple_plan.jpg"
"https://www.explainxkcd.com/wiki/index.php/97:_A_Simple_Plan"
"[Cueball, standing in front of stool with a radio on it.] Radio: You don't know what it's like to be me! [Caption below the panel:] At first, I loved A Simple Plan . Then I realized, with creeping horror, that they were serious. "
"The song on the radio is " Welcome to My Life " by Simple Plan (not A Simple Plan), which was released in 2004 as a first single from the band's second album " Still Not Getting Any... " The lyrics of the song mainly deal with the frustration of adolescence and the stress of newfound independence. Many, if not all, adolescents go through a phase where the ongoing realization of becoming fully responsible for their body, mind, and personality frightens them. Simple Plan's lyrics seem particularly inappropriate and ridiculous, given that the members of the band are all in their 30s. The absurdity of middle-aged men expressing teen angst could be interpreted as a spoof or parody, which Cueball mistakenly believes to be the truth. In the comic, Cueball slowly comes to the horrifying realization that the members of the band are actually seriously whining about the typical life of a spoiled teenager, rather than parodying them. In the title text, Randall states that this was his own reaction to the song, and that he now considers it ridiculous. [Cueball, standing in front of stool with a radio on it.] Radio: You don't know what it's like to be me! [Caption below the panel:] At first, I loved A Simple Plan . Then I realized, with creeping horror, that they were serious. "
98
"Fall Apart"
"Fall Apart"
"https://www.xkcd.com/98"
"https://imgs.xkcd.com/comics/fall_apart.jpg"
"https://www.explainxkcd.com/wiki/index.php/98:_Fall_Apart"
"[Various people struggle as the comic disintegrates. Toward the top, people are standing calmly, some holding hands. As the parts of the comic break apart, people try to reach for each other, hold parts together, or curl up into a ball. By the bottom, a Cueball is falling, surrounded by pieces of the comic.] "
"Despite Randall being enthusiastic about receiving ink pens, his first experiment with them has resulted in a rather bleak comic. Instead of multiple panels, the entire comic is a single drawing, with an apparent passage of time as we travel down the page. The frame, which represents the world of the characters, gradually disintegrates and leaves them falling helplessly. At the top, we see some people standing alone, apparently happy enough, and a couple. As we descend the page, we see examples of a couple split by a narrow chasm, someone huddled isolated and alone on their own world fragment, a couple desperately trying to hang on to each other, and a single figure falling chaotically and without control. The comic seems to be expressing what it feels like to someone when a relationship breaks up — their world falls apart, and one of the implications is that the process cannot easily be reversed. In short, it is catastrophic. The identity of '#pugglewumper Tashari,' the supplier of the pens, is not known. Judging by the use of the hash sign, it is someone with whom Randall communicates in IRC . In fact, 'pugglewump' appears to be an IRC channel. Although hashtags later came to be strongly associated with Twitter , this was not true at the time the comic was drawn. [Various people struggle as the comic disintegrates. Toward the top, people are standing calmly, some holding hands. As the parts of the comic break apart, people try to reach for each other, hold parts together, or curl up into a ball. By the bottom, a Cueball is falling, surrounded by pieces of the comic.] "
99
"Binary Heart"
"Binary Heart"
"https://www.xkcd.com/99"
"https://imgs.xkcd.com/comics/binary_heart.jpg"
"https://www.explainxkcd.com/wiki/index.php/99:_Binary_Heart"
"[All the numbers are black except for a heart-shaped red section in the middle.] "
"An array of zeros and ones is depicted, 21 across by 23 down. Some of the zeros and ones are red instead of black to form the shape of a Valentine heart. The digits themselves are an ASCII bit stream reading: The final octet is incomplete, but the three bits that are present are consistent with the start of an "e". The mixture of upper-case and lower-case "O"s is presumed intentional to avoid a repeating pattern. [All the numbers are black except for a heart-shaped red section in the middle.] "
100
"Family Circus"
"Family Circus"
"https://www.xkcd.com/100"
"https://imgs.xkcd.com/comics/family_circus.jpg"
"https://www.explainxkcd.com/wiki/index.php/100:_Family_Circus"
"[Picture shows a pathway winding through trees to a sink inside a house, out to some swings and back to the sink, out to a ball and back to the sink, then on into the house.] Jeffy's ongoing struggle with obsessive-compulsive disorder "
"The Family Circus is a comic characterized by single-panel round comics with a caption below the comic. Jeffy is a character in Family Circus , and dotted lines representing his wanderings are a frequent theme of Family Circus comics. Obsessive-compulsive disorder (OCD) is a mental illness that compels the sufferer to perform repetitive actions. Common symptoms include, but are not restricted to, excessive hand washing and repeated opening and closing of a door. The comic depicts the character Jeffy as having Obsessive-Compulsive Disorder and traces his movements over a period of time. The dotted line that depicts his movements returns frequently to the kitchen sink, presumably to repeatedly wash his hands. In the title text, Randall attributes this idea to the unknown friend David . He did the same in 42: Geico and 51: Malaria . [Picture shows a pathway winding through trees to a sink inside a house, out to some swings and back to the sink, out to a ball and back to the sink, then on into the house.] Jeffy's ongoing struggle with obsessive-compulsive disorder "
End of preview (truncated to 100 rows)
# Dataset Card for "XKCD"
### Dataset Summary
XKCD is an export of all XKCD comics with their transcript and explanation scrapped from https://explainxkcd.com.
## Dataset Structure
### Data Instances
• id: 1
• title: Barrel - Part 1
• image_title: Barrel - Part 1
• url: https://www.xkcd.com/1
• image_url: https://imgs.xkcd.com/comics/barrel_cropped_(1).jpg
• explained_url: https://www.explainxkcd.com/wiki/index.php/1:_Barrel_-_Part_1
• transcript: [A boy sits in a barrel which is floating in an ocean.] Boy: i wonder where i'll float next? [A smaller frame with a zoom out of the boy in the barrel seen from afar. The barrel drifts into the distance. Nothing else can be seen.]
• explanation: The comic shows a young boy floating in a barrel in an ocean that doesn't have a visible end. It comments on the unlikely optimism and perhaps naïveté people sometimes display. The boy is completely lost and seems hopelessly alone, without any plan or control of the situation. Yet, rather than afraid or worried, he is instead quietly curious: "I wonder where I'll float next?" Although not necessarily the situation in this comic, this is a behavior people often exhibit when there is nothing they can do about a problematic situation for a long time; they may have given up hope or developed a cavalier attitude as a coping mechanism. The title text expands on the philosophical content, with the boy representing the average human being: wandering through life with no real plan, quietly optimistic, always opportunistic and clueless as to what the future may hold. The isolation of the boy may also represent the way in which we often feel lost through life, never knowing quite where we are, believing that there is no one to whom to turn. This comic could also reflect on Randall's feelings towards creating xkcd in the first place; unsure of what direction the web comic would turn towards, but hopeful that it would eventually become the popular web comic that we know today. This is the first in a six-part series of comics whose parts were randomly published during the first several dozen strips. The series features a character that is not consistent with what would quickly become the xkcd stick figure style. The character is in a barrel. In 1110: Click and Drag there is a reference to this comic at 1 North, 48 East . After Randall released the full The Boy and his Barrel story on xkcd, it has been clear that the original Ferret story should also be included as part of the barrel series. The full series can be found here . They are listed below in the order Randall chose for the short story above:
### Data Fields
• id
• title
• url: xkcd.com URL
• image_url
• explained_url: explainxkcd.com URL
• transcript: english text transcript of the comic
• explanation: english explanation of the comic
## Dataset Creation
The dataset was scrapped from both explainxkcd.com and xkcd.com. The dataset is therefore licensed under the Creative Commons Attribution-ShareAlike 3.0 license for the transcript and explanation fields, while the image itself is licensed under the Creative Commons Attribution-NonCommercial 2.5 license.
See the Copyrights page from explainxkcd.com for more explanations.
### Update
You can update the dataset by using the scrapper.py script. First install the dependencies:
pip install aiolimiter aiohttp beautifulsoup4 pandas
Then run the script:
python scrapper.py
## Considerations for Using the Data
As the data was scrapped, it is entirely possible that some fields are missing part of the original data.
The dataset is licensed under the Creative Commons Attribution-ShareAlike 3.0 license for the transcript and explanation fields, while the images are licensed under the Creative Commons Attribution-NonCommercial 2.5 license.
| 2022-12-04T18:59:43 |
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|
https://bridgedale360.gen-europe.org/mod/forum/view.php?id=22
|
## Money Game
flickr photo shared by funkandjazz under a Creative Commons ( BY-NC-ND ) license
## Introduction
The rich get richer and the poor get poorer - a catchphrase most of us have come across. But what are the reasons for this growing rich-poor gap? How does the current banking system enable this?
Imagine you want to buy a house, but you do not have the money to do so. What do you do? You go to a bank to take a loan. What a great invention banks are, right? Well, let’s look into that briefly. Instead of just paying back the sum you borrowed, you also pay back interest on that sum - which goes to both the bank and the lender. The lender is a person that put their money in the bank for safety reasons and among other things, to earn from lending to poor people like you through - yes, you are right - the miracle of interest! And this is how wealth accumulates in the hands of the few.
The alternative and is there any? It is no coincidence that historically usury (interest-based loans) was prohibited in different cultures, including the Roman empire, ancient China, ancient Greece etc and it was usually interconnected with the condemnation of charging interest at lent money.
Money is associated with power and control as well as dependence or feeling of being taken care of. In this activity, we explore our relationship to money. In addition to that, we look into how the system, where most of the money in circulation is created out of thin air by commercial banks when they issue loans - meaning it has to be paid back with interest - affects us all.
## Activity Type
Group / Experiential
## Duration
Simple version: 30 min, complex version: 2 hours
## Learning Outcomes
• To better understand the feelings and beliefs we have about money in our lives and in society
• To gain a deeper insight into how the current banking system and interest work
## Instructions
### Required Materials and Tools:
• Real money, preferably in small coins and bills, the amount is up to you. It has been played with amounts varying from $1 to$200
• A journal and pen or pencil
• Time keeper
• Bell
### Step-by-Step Instructions for simple version:
1. Each person brings a certain amount of money, preferably small coins and bills. It should not be too big a sum so that you don’t lose all your money/go bankrupt, but it still has to be an amount that would cause you discomfort if you were to lose it. If some people don’t want to participate, that is fine as long as they don’t interfere with the others playing.
2. Split the participants in groups of 4, 5 or 6 people and ask them so sit on the floor or around tables so that they can clearly place their money in front of them and easily reach out for other people’s money.
3. Allow some time for people to prepare a piece of paper and a pen to write down their reflections later on.
4. Explain that there will be several 1-minute rounds. After each 1-minute round, ask the participants to stop the activity; you could signal this with a bell or such like. The whole activity should be happening in silence.
5. Round 1: explain to participants that they should take the money in front of them (their money) and give the entire sum to the other participants in their small group (it does not matter to whom they give it). Make sure it is clear whose money is where. After 1 minute, ring the bell and ask the participants to stop the activity. Then, ask the participants to shortly write down their personal observations. How did giving away their money make them feel?
6. Round 2: explain to participants that now they should take money from others and put it in their own pile. They should try to take as much as possible and only from the people in their group. Again, make the bell sound after a minute and let them write down how the second round make them feel.
7. Round 3: explain to participants that now they can take money from whomever and give to whomever. Again, make the bell sound after a minute and let them write down how they feel.
8. Round 4: first ask each participant to take away 20% of the money in front of them. The 20% from all the people playing in the small group is placed in a separate spot - “ the bank” and this money will not be included in this round. Explain to participants that now again they should take money from others and put it in their own pile. After a minute stop the process and ask them to check who is the person that has the most money in front of them. This person also gets the 20% from everybody else that was put in “the bank”. Explain the 20% interest-related money accumulation by making reference to the current banking system - the richer get richer and the poorer get poorer. Make sure to also introduce the concept of interest-free banking, as mentioned in the activity introduction above. Ask people to write down their reflections, by also reflecting on an interest-free banking system.
9. You can say that in the real world nobody cares how they feel about the money and that you also don’t want to know how they felt during the game. Each person keeps the money gained during the game. Of course other options are possible if people don’t feel comfortable with that, let people figure it out themselves. (ex: each person takes back the amount they brought; if somebody made extra money, she/he doesn’t give it back but buys some sweets and shares them with the group; all the money collected in each group is split up among all participants equally; all the money in each group is split up in a solidarity way, so the ones that are in a more precarious situation get more etc).
10. Do invite people to share in a group how they felt and what they observed during the entire process. Use the questions from the reflection section.
To play the a more complex version of the game look for instructions under “Support Files”!
## Reflection
• What are the main lessons learned from this activity?
• How is the last round and 20% given to the “richest” person connected to the current banking system with interest?
• How did the participants share the money in the end - did each take back the money they invested or was some other solidarity-based model adopted?
• What types of reflections did the participants write on the pieces of paper, what was their relationship to money?
## Instructions for Submission
Upload your written reflection, so that your peers can give you feedback. Instructions on how to upload a picture in Moodle or submit your written reflection can be found here: Instructions on Submission&Uploading
## Instructions for Assessment
Provide feedback to at least one participant that has done this activity. Instructions on providing feedback can be found here: Instructions on Feedback
## Author
Creative Commons - ySI4R Content Team - inspired by the exercise from Margrit Kennedy.
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| 2023-03-30T14:36:00 |
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https://dup.silverchair.com/demography/article/59/5/1739/317747/Long-Term-Exposure-to-Neighborhood-Policing-and
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## Abstract
Researchers are increasingly exploring the consequences of policing for the educational outcomes of minority youth. This study contributes to this literature by asking three questions. First, what are racial/ethnic disparities in long-term exposure to neighborhood policing? Second, how does this exposure affect high school graduation? Third, how much of the ethnoracial gap in high school graduation would remain if neighborhood policing was equalized? To address these questions, we use data from the New York City Department of Education and follow five cohorts of NYC public school students from middle to high school. Our findings reveal starkly different experiences with neighborhood policing across racial/ethnic groups. Using novel methods for time-varying treatment effects, we find that long-term exposure to neighborhood policing has negative effects on high school graduation, with important differences across racial/ethnic groups. Using gap-closing estimands, we show that assigning a sample of Black and Latino students to the same level of neighborhood policing as White students would close the Black–White gap in high school graduation by more than one quarter and the Latino–White gap by almost one fifth. Alternatively, we explore interventions where policing is solely a function of violent crime, which close the Black–White gap by as much as one tenth. Our study advances previous research by focusing on cumulative, long-term exposure to neighborhood policing and by assessing various counterfactual scenarios that inform research and policy.
## Introduction
Neighborhood policing is an important aspect of urban life that is central to debates about racial inequities. Previous research has shown that exposure to neighborhood policing has a negative impact on academic performance and other outcomes (Ang 2021; Gottlieb and Wilson 2019; Hirschfield 2009; Hjalmarsson 2008; Kirk and Sampson 2013; Legewie and Fagan 2019; Shedd 2015). This research focuses on single incidents of police stops, arrests, or acts of police violence and short-term exposure to neighborhood policing. Exposure to policing, however, cumulates over extended periods of time, such that systematic ethnic and racial differences in exposure can grow over adolescence, resulting in cumulative disadvantages for minority youth (Justice 2021). Building on prior research on the temporal dimensions of neighborhood effects (Wodtke et al. 2011), our study contributes to this growing literature by focusing on ethnic and racial disparities in long-term exposure to neighborhood policing.
Using administrative data from the New York City Department of Education and the New York City Police Department, we follow five cohorts of 231,177 NYC public school students over an eight-year period from middle to high school. First, we document racial and ethnic disparities in long-term exposure to neighborhood policing over key developmental periods. Second, we focus on the effect of long-term exposure to policing on high school graduation. Using innovative methods for time-varying treatment effects (Wodtke et al. 2011; Zhou and Wodtke 2020) allows us to examine the role of cumulative exposure across middle and high school. These models address the dynamic relation between neighborhood crime and policing, in which the level of policing in one period is affected by crime in previous periods. Third, using novel gap-closing estimands, we assess several counterfactual scenarios that help us understand how the racial/ethnic gap in high school graduation would change for a sample of students if exposure to neighborhood policing were equalized or based solely on neighborhood crime (Lundberg 2021).
Descriptively, we show that differential neighborhood policing cumulates to create striking ethnic and racial disparities in exposure to the criminal justice system over adolescence. Though levels of neighborhood policing decline over the observation period, ethnic and racial disparities in cumulative exposure persist across cohorts. We also show that the cumulative nature of exposure matters: compared with our measure of cumulative exposure, focusing on a single year of exposure during middle or high school understates the negative impact of neighborhood policing on minority students' high school graduation rates. Counterfactual scenarios illustrate that assigning a sample of Black and Latino students to the same level of neighborhood policing as White students would reduce the Black–White gap in high school graduation by 27.8% and the Latino–White gap by 17.5%. However, assigning neighborhood policing solely as a function of violent crime reduces the Black–White gap to a more modest extent by 10.3%.
Our results highlight policing as one of many mechanisms through which neighborhoods shape children's life chances (Chetty et al. 2014; Harding et al. 2010; Sampson 2012) and create starkly different residential experiences for Black and White youth (Massey and Denton 1993; Peterson and Krivo 2010). By showing how long-term exposure to neighborhood policing matters for high school graduation in addition to crime and other common neighborhood characteristics (Sharkey and Torrats-Espinosa 2017; Torrats-Espinosa 2020), these findings also heed the call to examine how policing shapes social structure above and beyond its effects on crime (Bell 2021).
## Neighborhood Policing and Educational Outcomes
A growing effort among social scientists has examined how ethnic and racial inequalities in direct and indirect contact with the criminal justice system shape educational outcomes. Researchers focusing on direct criminal justice system exposure have suggested that students who experience arrests (Hirschfield 2009; Kirk and Sampson 2013; Lopes et al. 2012; Sweeten 2006) and juvenile incarceration (Aizer and Doyle 2015) are more likely to drop out of high school and less likely to enroll in higher education (Kirk and Sampson 2013; Widdowson et al. 2016). Other research has documented the deleterious effects of indirect exposure to the criminal justice system on educational outcomes via parental incarceration (for a review, see Foster and Hagan 2009, 2015), vicarious exposure through friends or family members (Gottlieb and Wilson 2019), or exposure to neighborhood and school-level policing (Ang 2021; Bacher-Hicks and de la Campa 2020; Browning et al. 2021; Legewie and Fagan 2019). This work has consistently documented the negative effects of various types of direct and indirect criminal justice contact on educational outcomes, such as test scores or high school graduation.
Most important for the current study, several articles have focused on neighborhood- or school-level exposure to policing. Legewie and Fagan (2019), for example, showed that neighborhood-level exposure to aggressive policing programs has substantial negative impacts on minority children's test scores, with larger effects for Black than for Latino students. Ang (2021) focused on incidents of police violence in the residential environment and similarly found negative effects on minority students' GPA, with no effects on White students. Closely related research has focused on school-level exposure to police stops and documented comparable negative effects on Black students' high school graduation rates, with potential positive effects for White students (Bacher-Hicks and de la Campa 2020). This work has consistently found larger effects on Black students as the racial group disproportionally targeted by policing.
Two key mechanisms explain the effect of neighborhood-level proactive policing on educational outcomes. The first focuses on eroded trust in state institutions and system avoidance. Negative encounters with the police—such as mistreatment, procedural injustice among friends and family members, or neighborhood-level exposure to aggressive policing programs—can negatively impact perceptions of police legitimacy, reduce trust in government, and lead to withdrawal from state institutions, including schools (Bell 2020; Geller and Fagan 2019). Other research has focused on broader systems of surveillance across state institutions, describing system avoidance as a behavioral response in which individuals avoid institutions that are involved in surveillance and keep formal records (Brayne 2014:368). Both distrust in law enforcement and avoidance of state institutions have implications for educational outcomes, such as high school graduation. Indeed, empirical research has directly tied system avoidance following paternal incarceration to reductions in parental involvement in schooling (Haskins and Jacobsen 2017), and a national analysis from the Urban Institute found that more than 65% of high school students attend schools with a law enforcement presence (Lindsay et al. 2018). Exposure to police officers at school, together with zero-tolerance discipline policies, highlights how distrust of the legal system may impact school attendance and educational outcomes more broadly.
A growing literature documents a second mechanism, which focuses on the negative health effects of police contact that can impact children's educational performance. Geller et al. (2014), for example, showed that participants who report prior encounters with the police display higher rates of trauma and anxiety, particularly when stops were intrusive or perceived as unfair. Building on the stress process paradigm, Sugie and Turney (2017) looked at a set of criminal justice contacts, including arrest, conviction, and incarceration, and found negative consequences for mental health. Sewell and colleagues focused on neighborhood-level exposure to policing and showed similar negative effects on stress, trauma, anxiety, and other mental health problems (Sewell and Jefferson 2016; Sewell et al. 2016; Sewell et al. 2020). Toro and collaborators (2019) linked these health effects to educational outcomes. They showed that part of the relationship between direct and vicarious police contact and grades in school is mediated by psychological distress, sleep problems, and self-rated health. Both processes explain the potential effect of neighborhood-level proactive policing on educational outcomes.
## Cumulative Exposure to Neighborhood Policing and the Racial/Ethnic Gap in High School Graduation
While previous research has documented the social consequences and costs of proactive policing programs for the education of minority youth, this work focused either on single incidents of police stops, arrests, or acts of police violence or on short-term exposure to neighborhood policing. For example, Legewie and Fagan (2019) examined the effect of immediate exposure to an aggressive policing program over a single year on test scores, and Ang (2021) focused on the acute effect of police killings in the residential environment on GPA. This approach ignores the potential for cumulative effects of exposure to policing over extended periods of time that are experienced by many minority youth. In the present study, we follow five cohorts of middle school students in New York City over eight years and focus on long-term exposure to policing throughout adolescence. This longitudinal perspective advances the literature in three important ways.
First, research focused on the acute or “short-run” effects of neighborhood policing potentially underestimates the effect of cumulative exposure. Many of the mechanisms at the core of policing effects and the effects of racism on individual outcomes focus on long-term and repeated exposure. System avoidance and legal estrangement, for example, are cumulative processes of disengagement from formal institutions that develop in response to sustained and repeated experiences of injustice over an extended period of time (Bell 2017). Incidents of police violence, racial discrimination, or other encounters that initially act as acute stressors translate to chronic stressors with additional health consequences as a result of sustained and repeated exposure to policing and structural racism. Accordingly, the focus on long-term exposure to neighborhood policing documents the cumulative effect that is essential for understanding the consequences of neighborhood policing for child development.
Second, a longitudinal perspective allows us to better measure racial and ethnic disparities in exposure to neighborhood policing. Policing in New York City and many metropolitan areas underwent major changes over recent decades. After a steep increase in the use of the Stop, Question, and Frisk (SQF) operations during the 2000s, the use of police stops peaked in 2011 with over 650,000 incidents. In response to the public outcry against the SQF program and the Floyd v. City of New York lawsuit, the New York Police Department (NYPD) dramatically reduced the number of stop and frisk operations over the following years, reaching about 45,000 in 2014. As a result, early cohorts in our sample were exposed to an average of 2,210 police stops in their residential census tract, compared with an average of 1,157 stops for later cohorts. At the same time, families move between neighborhoods, with implications for their local exposure to neighborhood policing (de Souza Briggs and Keys 2009; Wodtke et al. 2011). In light of these shifts, a longitudinal perspective more accurately reflects the experiences of adolescents in their neighborhoods.
Third, a longitudinal perspective allows us to disentangle the dynamic relationship between neighborhood policing and neighborhood crime. The latter is associated with both neighborhood policing and children's' educational attainment (for a review, see Sharkey 2018), and behavioral adaptations to crime develop over extended periods (Harding 2009). Policing can thus have positive consequences for youths' educational outcomes by reducing students' exposure to violent crime over time. Research suggests that declines in violent crime attributable to exogenous increases in the availability of funds to hire police officers via federal funds substantially raised English Language Arts (ELA) test scores, particularly among Black youth (Torrats-Espinosa 2020). Examining the effect of recent exposure to police stops while adjusting for violent crime might thus control away the positive impact of prior levels of policing on declines in subsequent crime levels. Our longitudinal perspective uses novel methods to adjust for time-varying confounders, allowing us to examine the effect of policing on children's high school graduation while considering the dynamic relationship between neighborhood policing and crime.
Together, these advances allow us to more precisely measure and assess the consequences of exposure to neighborhood policing, with implications for our understanding of its effects on child development, urban inequality, and the racial/ethnic gap in high school graduation. To leverage these insights, we further study several counterfactual scenarios that help us assess how the racial/ethnic gap in high school graduation would change depending on different levels of exposure to neighborhood policing.
## Data and Methods
### Data
Our analyses follow five cohorts of middle school students over eight years using administrative school district records from the New York City Department of Education. The school district records consist of student-level data from all NYC public school students in grades 6 to 12 from the school years 2006 to 2018. We focus our analysis on the 2005–2006 to 2009–2010 (five) cohorts of middle school students. Each cohort is defined as all students who enrolled in sixth grade for the first time in a respective school year. We track these cohorts for eight years to capture their long-term exposure to neighborhood policing during an important developmental period prior to our key outcome variable, high school graduation.
We link student data to information on pedestrian stops from the SQF program and crime complaints from the NYPD based on residential census tracts. The SQF program regulates police stops in situations where officers reasonably suspect that a person has committed, is committing, or is about to commit a felony or a Penal Law misdemeanor (Ridgeway 2007). Stops are well documented and reliably recorded on the “Stop, Question and Frisk Report Worksheet” (UF-250 form) during the height of the SQF program, but they are possibly underreported in later years (Braga et al. 2022; Eterno and Silverman 2012; Ridgeway 2007). The possible underreporting of stops in later years is an important data limitation and is discussed later. NYPD crime complaints include geocoded, incident-level felony, misdemeanor, and violation crimes reported to the NYPD. Official crime data are limited to incidents known to the police through citizen or police reporting. This data limitation, however, is less problematic when studying police behavior because police cannot respond to crime that is unknown to them. While unreported crime likely impacts educational outcomes as well, it is presumably not related to neighborhood police stops or arrests and therefore is not a major concern for our analysis.
### Outcome
Our main dependent variable is high school graduation, which is a hugely important milestone in the educational trajectory of adolescents with implications for a range of social, economic, and health outcomes later in life (Rumberger 1987; Rumberger and Rotermund 2012). We measure whether students graduate within eight years from their initial enrollment in sixth grade, allowing for one additional year compared with on-time graduation. We exclude students who leave NYC public schools (see following details), so our analyses compare graduating students to students who drop out or are still actively enrolled at the end of our observation period.
### Treatment and Covariates
Our main independent variable measures cumulative, neighborhood-level exposure to police stops in the six years after students enroll in sixth grade. SQF operations in New York City were a core component of proactive policing programs that use police stops to engage citizens, targeting low-level crimes and minor disorderly behavior (Zimring 2013). These operations are particularly salient for middle and high school students because they frequently target young people of color (Figures and Legewie 2019; Geller 2021). In supplementary analysis, we present results for the cumulative number of low-level arrests, defined as all misdemeanor and violation arrests in students' residential census tract. While arrests are still uncommon for students in our sample, they are an alternative measure of proactive policing that allows us to assess the robustness of our findings.
We define $At∈{0,1,2...5}$ as the number of police stops in a student's residential census tract during the fall term of the calendar year. To measure cumulative exposure to police stops, we sum over years 1 to 5 as and divide this student-level measure into quintiles defined over all students in the sample.1 The result is a categorical measure of cumulative exposure to neighborhood policing in the residential environment during middle and high school, ranging from very low to very high. “Very low” indicates that a student experienced between 0 and 201 police stops during years 1 to 5 (first quintile), “low” indicates 202 to 393 stops (second quintile), “average” indicates 394 to 680 stops (third quintile), “high” indicates 681 to 1,208 stops (fourth quintile), and “very high” indicates 1,209 to 10,866 stops (fifth quintile). Compared to a continuous measure, this categorical variable provides two key advantages:2 first, it allows us to measure nonlinear effects of cumulative exposure to neighborhood policing, and second, it makes it possible to identify gap-closing estimands and therefore directly link the two parts of our analysis.
In additional analysis, we measure exposure to police stops during a single year in either middle or high school. These measures are similarly divided into quintiles for “middle school exposure” (t = 1) and “high school exposure” (t = 3). They allow us to compare the effect of cumulative exposure with short-term exposure over a single year, as is more commonly used in previous research.
In addition, we use three measures of crime as time-varying, neighborhood-level covariates $Ltx∈{0,1,2...5}$: the number of violent crimes, the number of property crimes, and the number of misdemeanors in the spring term. To ensure a clear temporal order between treatment and confounders across our analyses, these time-varying confounders are measured during the spring term, while the treatment variable is measured during the fall term of the same calendar year. Table A1 in the online appendix illustrates this temporal structure for the 2005–2006 middle school cohort.
Finally, our analyses include baseline covariates on the student and neighborhood levels. On the student level, we control for cohort, gender, free lunch status as a measure of parental socioeconomic background, English learner status as a measure of immigrant background, and sixth-grade ELA and mathematics test scores. Both free lunch status and English learner status are binary variables that indicate whether a student ever received free lunch or was designated as an English learner by the NYC Department of Education. Adjusting for cohort ensures that we control for all time-specific characteristics that are common across students from the same cohort, such as general economic conditions or changes in the reporting practices of police stops (including possible underreporting).
On the neighborhood level, we control for several characteristics of student's baseline neighborhood (residential census tract in sixth grade) derived from the 2010 decennial census and the 2006–2010 American Community Survey five-year estimates. These variables include police precinct fixed effects; population size; racial composition in terms of proportions Black, Asian, Latino, and other residents, with proportion White as a reference; residential instability; and concentrated disadvantage. The last two variables are indices constructed from an exploratory maximum likelihood factor analysis with one-factor solutions. The factor analysis for concentrated disadvantage includes poverty rate, unemployment rate, professional jobs, share of high school graduates, and share of single-mother families; that for residential instability includes percentage of renter-occupied units, share of residents who moved between 2000 and 2009, and housing unit rental vacancy rate. Concentrated disadvantage and residential instability are both standardized on the neighborhood level. Finally, we control for cumulative exposure to police stops around school defined as the number of police stops within 500 meters of a school. This control variable ensures that our results for neighborhood-level exposure to policing are not driven by exposure to policing at school.
Table 1 provides summary statistics for all the variables by race and ethnicity.
### Estimation Strategy
Estimating the effect of cumulative exposure to neighborhood police stops on high school graduation is challenging because policing is a time-varying treatment that is closely linked to crime. The level of neighborhood crime at a particular point in time is affected by recent policing, which itself is influenced by previous criminal activity. This dynamic relationship raises concerns about posttreatment confounding (Zhou and Wodtke 2020). The naive approach to condition on posttreatment confounders is problematic because it may induce bias by blocking causal pathways, controlling away the effect of the treatment on the outcome that operates through the time-varying confounder, or by leading to spurious associations between treatment and outcome via collider stratification bias if these confounders share unobserved common causes with the treatment.
One approach to overcome this challenge is the use of marginal structural models with residual balancing to construct weights designed to account for dynamic causal relationships between time-varying treatments and confounders (Imai and Kim 2019; Wodtke et al. 2011; Zhou and Wodtke 2020). Residual balancing requires modeling the conditional means of the posttreatment confounders $Xj$ to obtain a set of weights that balance the residuals from these models across future levels of treatment A and prior levels of the treatment and the confounders. Estimating marginal structural models using these weights creates a pseudo-population where time-varying, posttreatment confounders ($Xit$) do not predict future treatments, conditional on prior values of the treatment ($Ait$) and prior values of the confounder (). In this pseudo-population, the residualized posttreatment confounders $X′it$ are balanced across levels of the treatment $Ait$ while remaining uncorrelated to the observed past (and ). This procedure properly adjusts for biases arising from posttreatment confounding without overcontrolling for the effect of the treatment or inducing collider stratification bias. For details on the implementation and construction of weights, see Zhou and Wodtke (2020).
In the context of this study, we implement residual balancing to purge the effects of crime on policing from posttreatment confounding. We model all time-varying control variables as a function of lagged measures of time-varying control () and treatment variables (). These time-varying variables j include counts of violent, property, and misdemeanor crimes during the spring term, modeled as a function of the treatment during the previous fall, and counts of violent, property, and misdemeanor crimes during the preceding spring.3 We then implement the residual balancing procedure with the R package rbw (Zhou and Wodtke 2020). Using the reweighted sample, we estimate the following marginal structural model:
where refers to four indicator variables for low, average, high, and very high level of neighborhood policing in student i's residential neighborhood from years 2 to 6 in our sample (t = 1 to t = 5) as a measure of cumulative exposure. $Xi$ represents the time-invariant covariates on the student level, such as gender, free lunch and English learner status, sixth-grade ELA and mathematics test scores, and indicator variables for four of the five cohorts, with the 2005–2006 cohort as the reference category. Finally, $Uj$ represents the baseline control variables on the neighborhood level (census tract in grade six) and includes police precinct fixed effects; population size; racial composition in terms of proportions Black, Asian, Latino, and other residents; residential instability; and concentrated disadvantage.
These models provide unbiased and consistent estimates of marginal effects for the target population under three key assumptions. The first assumption is that the models for the conditional mean of the time-varying confounders are correctly specified. Misspecifying these models can lead to a weighted pseudo-population in which future treatments are orthogonal to the time-varying covariates without resembling the target population, leading to bias in estimates of the treatment effect for the population of interest (Zhou and Wodtke 2020). We mitigate these concerns by checking the robustness of our estimates to different model specifications for the time-varying covariates, where we (1) include a set of baseline confounders in the models for the time-varying covariates and (2) estimate similar models on a subset of a sample for which we have additional sets of measured time-varying covariates. The second assumption states that the specified balancing conditions are sufficient. We mitigate these concerns by assessing the robustness of our estimates when we include interactions between the time-varying covariates and higher order terms in the models for the time-varying confounders. Finally, similar to other research using marginal structural models, our estimates are subject to the sequential ignorability assumption, stating that, conditional on past treatments and observed confounders, the treatment at each time point is unconfounded by unobserved confounders including unobserved individual characteristics. Compared to other recent research on the effects of neighborhood- or school-level exposure to policing, our approach comes with trade-offs. It allows us to examine the effects of long-term exposure to neighborhood policing stops while accounting for the dynamic relation between policing and crime, but does not leverage more plausibly exogenous sources of variation from quasi-experimental designs such as Legewie and Fagan (2019), Bacher-Hicks and de la Campa (2020), or Ang (2021).
### Gap-Closing Estimates
In the second step of our analyses, we use gap-closing estimands to determine how the racial/ethnic gap in high school graduation would change depending on different levels of exposure to neighborhood policing (Lundberg 2021; VanderWeele and Robinson 2014). Though related to Kitagawa–Blinder–Oaxaca decompositions (Blinder 1973; Kitagawa 1955; Oaxaca 1973), gap-closing estimands are distinct in that they explicitly invoke a causal claim: they are defined as the disparity in an outcome (such as high school graduation) we would expect across groups (such as race/ethnicity) when a sample of the population receives a counterfactual intervention to the treatment (such as exposure to neighborhood policing). The counterfactual treatment assignment can be either fixed to a certain value or stochastic.
In our analysis, we examine how the racial/ethnic gap in high school graduation would change under four counterfactual scenarios: (1) if we intervened so that all students experienced very low levels of neighborhood policing; (2) if a sample of students all experienced the same level of neighborhood policing as White students; (3) if the level of neighborhood policing was entirely determined by the level of crime; and (4) if the level of neighborhood policing was solely based on crime, but using the policing–crime relation for the last cohort in our sample. Over the study period, the use of SQF dramatically declined, so that in later years the same number of violent crimes predict a lower level of policing.
Identifying gap-closing estimands directly builds on our estimation strategy discussed earlier. In particular, we convert the function to predict the outcome from the foregoing marginal structural model to an estimate of the gap-closing estimand using the g-formula (Hernán and Robins 2020:166; Lundberg 2021). To implement this approach, we first use the outcome model to predict unobserved potential outcomes under all five possible values of the treatment variable (neighborhood police stops). We then calculate the group-specific estimates of the expected outcome under each counterfactual assignment rule by averaging over all observations in each group weighted by the sample weight and assignment probability for each treatment category. The difference in these group-specific estimates of the predicted outcome is an estimator of the gap-closing estimand, and the standard errors are based on bootstrapping (for more details, see Lundberg 2021:18).4 Their causal interpretation is subject to the same assumptions discussed earlier.
### Sample Restrictions and Missing Data
We restrict our analytic sample in several ways. First, we focus on White, Black, and Latino students because the sample size is sufficiently large to support our analysis. This restriction leaves us with 287,064 students across five cohorts. Second, our analyses exclude 55,887 students (19.47%) who left NYC public schools before the end of our observation period because they transfer to a private school, leave the NYC school district, or are discharged for other reasons that are not related to graduation or dropout. This restriction is an important limitation of administrative school district records that raises concerns about selection out of the sample. We address this challenge by using inverse probability weighting to control for various forms of attrition (for details, see Huber 2012). The weights are defined as the inverse of the predicted values from a logistic regression that predicts whether students remain in the sample using the same set of predictors as in the main analysis.
These restrictions leave us with an analytic sample of 231,177 students across five cohorts. The frequency of missing values is low for most variables, ranging from almost 0% to 3%. However, it is as high as 15.5% for free lunch status and English learner status, and is around 6% for other covariates. To address this issue, we use multiple imputation with five imputed data sets based on the chained equation approach (Van Buuren and Groothuis-Oudshoorn 2011). The imputation is based on a model that includes all relevant variables from the final analysis.
## Results
We begin by describing racial/ethnic disparities in long-term exposure to neighborhood policing. The five cohorts in our study came of age during a period of changing policing policies in New York City. Table 2 presents the average number of Stop, Question, and Frisk operations in students' residential environment (census tract) over a five-year period (cumulative exposure) by race/ethnicity and cohort.5 The average Black student in the 2005–2006 middle school cohort experienced 1,861 SQF operations in their census tract during middle and high school, or roughly 1.0 SQF operation per day. This cumulative exposure for Black students in the 2005–2006 cohort ranges from 319 stops for students in low-policing neighborhoods (5th percentile) to 7,835 stops for students in high-policing neighborhoods (95th percentile). Accordingly, some Black students were exposed to an average of 4.3 police stops in their census tract—a relatively small geographic area—every single day over this five-year period. For each subsequent cohort, the cumulative exposure declined (except for 2006–2007), reaching an average of 986 SQF operations for Black students in the 2009–2010 cohort. While SQF operations were likely underreported in later years (Braga et al. 2022), the decline reflects a substantial change in policing policy in NYC. Across the five cohorts, Latino students experienced slightly lower but overall similar levels of policing in their immediate residential environment. White students, however, were consistently exposed to substantially lower levels of policing. On average, White students in the 2005–2006 cohort were exposed to 568 police stops in their neighborhood over a five-year period, corresponding to 0.3 stops per day, compared with 1.0 and 0.9 stops per day for Black and Latino students, respectively. Cumulative exposure among White students further decreased for subsequent cohorts, averaging 299 police stops for the 2009–2010 cohort. While the level of policing substantially declined over time, racial disparities in cumulative exposure remained consistent. For the 2005–2006 cohort, the cumulative exposure ratio indicates that Black students were exposed to 3.27 times the number of police stops in their neighborhood as White students over middle and high school, and this ratio was remarkably constant across cohorts despite dramatic declines in the use of SQF. The Latino/White exposure ratio similarly remained relatively constant across cohorts on a slightly lower level (e.g., 2.97 for the 2005–2006 cohort).
In the next step of the analysis, we estimate the effect of cumulative, long-term exposure to SQF on high school graduation. Table 3 shows the results from marginal structural models for White, Black, and Latino students, and Figure 1 illustrates the key coefficients. Long-term exposure to SQF is associated with a decreased likelihood of graduating from high school for Black and Latino students, whereas the evidence for White students is mixed. Using “very low” exposure as the reference category (first quintile), we find a gradually increasing negative effect size for higher levels of exposure. For Black students, “low” compared to “very low” exposure to police stops during middle and high school is associated with a 2.3-percentage-point-lower graduation rate. “Average” exposure is associated with a 5.1-percentage-point-lower graduation rate, “high” exposure with a 6.6-percentage-point-lower rate, and “very high” exposure with an 8.8-percentage-point-lower rate. To put the size of this effect into perspective, 6.6- and 8.8-percentage-point-lower graduation rates correspond to 8.4% and 11.1% decreases, respectively, in the graduation rate for Black students (i.e., rates of 72.4% and 70.2%, respectively, compared with the observed graduation rate of 79.0%). The Black–White gap in high school graduation is 11.3 percentage points in our sample, and hence the estimated effect size corresponds to a substantial proportion of that gap.
Latino students similarly experienced a negative effect of police exposure on high school graduation, but the size of the effect is somewhat smaller. “High” compared with “very low” exposure to police stops is associated with a 4.9-percentage-point-lower graduation rate for Latino students, and “very high” exposure with a 4.7-percentage-point-lower rate. The difference in the effect size between Black and Latino students is meaningful but only statistically significant for “very high” exposure (see the “L–B” column in Table 3). For White students, the sample size is insufficient to draw clear conclusions, particularly for higher levels of exposure. While the point estimates indicate that White students experienced a smaller but still negative effect of cumulative exposure to policing, the uncertainty in the estimates is large and the estimates are not statistically significant. However, we do find statistically significant differences in the coefficient estimates between Black and White and between Latino and White students for most levels of exposure. Additional analysis presented in Table A3 in the online appendix shows similar patterns with somewhat smaller effect sizes for neighborhood exposure to low-level arrests on high school graduation, reaffirming the results with a different measure of proactive neighborhood policing.
Table 4 compares the effect of cumulative exposure to police stops for Black students with the effect of exposure over a single year in middle or high school. Table A4 in the online appendix presents the same results for White and Latino students. Overall, the effect size of cumulative exposure is larger compared with the effect of exposure during a single year in middle or high school, but the magnitude and statistical significance of these differences in effect size vary across the level of treatment. Compared with a single year of exposure during middle school, the effect of cumulative exposure on high school graduation is consistently larger, and this difference is statistically significant at the 0.01 level for the coefficients “average,” “high,” and “very high” in relation to “very low” SQF exposure. Comparing a single year of exposure to SQF during high school with cumulative exposure similarly shows that the effect size of cumulative exposure is either essentially the same (for the “low” compared to “very low” levels) or larger. However, the differences in effect size are statistically significant only for “very high” compared to “very low” exposure levels. These findings highlight the importance of focusing on long-term exposure to policing to understand the consequences of sustained experience with the police.
### Gap-Closing Estimands
The analyses so far reveal a large and statistically significant negative effect of long-term exposure to neighborhood policing on high school graduation. However, it remains unclear whether neighborhood policing plays a meaningful role in explaining the Black–White and Latino–White gaps in high school graduation and whether interventions to policing would reduce the gap. Figure 2 shows that the Black–White and Latino–White gaps are 11.3 and 11.7 percentage points, respectively, and persist across the five cohorts in our study. In the next part of the analysis, we use gap-closing estimands to determine how this racial/ethnic gap in high school graduation would change if we intervened to assign some students to a lower (or higher) level of exposure to neighborhood police stops under different counterfactual scenarios.
First, we examine how the racial/ethnic gap in high school graduation would change under a deterministic scenario, where we intervene to assign a sample of students to the lowest level of policing. As shown in Table 5, after assigning students to the lowest level of policing, the Black–White and Latino–White disparities would be reduced to 7.0 and 8.8 percentage points, respectively. These disparities would represent a 38.6% and 25.4% reduction of the gap, respectively, highlighting the degree to which the racial/ethnic gap in high school graduation is a consequence of neighborhood policing.
Second, we examine how the racial/ethnic gap in high school graduation would change if we intervened so that a sample of students experienced the same level of neighborhood policing as White students. The assignment rule is stochastic and based on the distribution of White students across the five categories of our treatment variable with the following assignment probabilities: 51.4% for the first quintile, 27.6% for the second, 13.0% for the third, 5.3% for the fourth, and 2.8% for the fifth. (See the online Table A5 for the assignment probabilities under each of the four interventions discussed here.) Under this intervention, the Black–White and Latino–White disparities would be reduced to 8.2 and 9.7 percentage points, respectively, which correspond to a 27.8% and 17.5% reduction of the gap. This reduced racial/ethnic gap in high school graduation rates is a result of both a larger effect of neighborhood policing on Black students and a substantial reduction in cumulative exposure for both Black and Latino students when assigning them to the distribution of exposure among White students. It indicates that group differences in exposure explain a substantial part of the gap in high school graduation, but important differences remain.
Third, we assess how the racial/ethnic gap in high school graduation would change if we intervened so that the level of neighborhood policing is entirely determined by the level of crime. For this purpose, we use student-level data from all five cohorts to predict cumulative exposure to police stops as a function of neighborhood crime using an ordered logistic regression. This model allows us to derive the assignment probabilities for all students using the predicted probabilities for each of the five categories of the treatment variable. Table A5 presents the average assignment probabilities by race/ethnicity. The results of the gap-closing estimates presented in Table 5 indicate that this intervention would do little to close the racial/ethnic gap in high school graduation. In particular, the Black–White and Latino–White disparities would remain at 11.2 and 11.7 percentage points, respectively, which correspond to a change of 1.1% and 3.4%. The reason for this finding is that basing policing on crime alone changes little about racial/ethnic disparities in police exposure, as documented in Table A5 for this third intervention.
Lastly, we focus on a similar intervention in which police exposure is solely a function of crime, but instead of using data from all cohorts, we use data from the 2009–2010 cohort—the last cohort in our study. This cohort came of age during a period of substantially lower levels of police stops (see Table 2). Compared with the previous intervention, cumulative exposure to policing under this intervention is lower across all racial/ethnic groups simply because the overall number of police stops dramatically declined over time: the same level of neighborhood crime predicts a lower level of police exposure (see Table A5). Under this intervention, the Black–White and Latino–White disparities in high school graduation would be 10.2 and 10.9 percentage points, respectively, which correspond to a modest reduction of 10.3% of the Black–White gap and a smaller change of 6.9% for the Latino–White gap. This counterfactual scenario informs two important issues. First, it speculates about a world without a spike in the use of police stops during the 2000s and early 2010s. SQF is one of the most prominent and controversial policing programs of the recent past. A generation of minority youth in New York City and other places with similar programs was exposed to startlingly high levels of police stops in their residential environment. Our results suggest that without the dramatic increase in the use of SQF, the Black–White gap in high school graduation would be 10.2 percentage points smaller, with higher graduation rates across all three groups. From a policy perspective, the intervention is informative because it explores the expected disparities in high school graduation under a largely race-neutral allocation of police resources. The counterfactual intervention is more realistic because police exposure is directly linked to crime, empirically informed by current levels of police stops, and continues to show racial/ethnic disparities. However, the intervention also assumes that the higher level of police stops in earlier years did not help reduce crime.
## Discussion
Policing is a divisive political issue that is central to debates about racial inequities. A growing body of research contributes to this debate and examines the social consequences and costs of policing for the health, education, and civic engagement of minorities. The results presented in this article contribute to this work by providing the first systematic assessment of long-term exposure to neighborhood policing. A longitudinal perspective highlights how unequal exposures to neighborhood policing cumulate over adolescence and allows us to disentangle the dynamic relationship between neighborhood policing, crime, and educational attainment.
Using administrative data from the New York City Department of Education and the New York City Police Department, we follow five cohorts of 231,177 NYC public school students over an eight-year period from middle to high school. First, we document racial and ethnic disparities in long-term exposure to neighborhood policing over key developmental periods. The longitudinal perspective crystallizes racial and ethnic disparities in exposure to neighborhood policing with profoundly different experiences for Black, Latino, and White youth. Similar to the way in which Massey and Denton (1993) (see also Peterson and Krivo 2010) described the lack of overlap in neighborhood conditions experienced by White and Black people in urban areas, a high level of neighborhood policing experienced by White students is comparable to the average experience for Black and Latino students. These disparities have important implications for our understanding of urban inequality and replicate disparities in other forms of criminal justice contact, such as arrest or incarceration (Weaver et al. 2019; Wildeman 2009).
Second, we examine the effect of cumulative exposure to policing across middle and high school on high school graduation using innovative methods for time-varying treatment effects. These models address the dynamic relation between neighborhood crime and policing, capturing the full effect of policing on educational attainment without “controlling away” the potentially beneficial effect of policing that operates indirectly through reductions in violent crime. Our results show that the effect of long-term exposure to SQF is large and statistically significant for Black students and, to a smaller extent, for Latino students. Furthermore, our analyses show that the effects of cumulative exposure matter above and beyond the effects of differences in exposure observed during single-year periods at different developmental stages. These findings illustrate that ignoring cumulative, long-term exposure to neighborhood policing underestimates the full extent to which policing impacts educational outcomes. They demonstrate that Black and Latino youth are more likely to experience aggressive forms of neighborhood policing throughout adolescence and are disproportionately impacted by this exposure. Together, the racial/ethnic differences in both exposure to and the effect of long-term neighborhood policing create a double disadvantage, particularly for Black students, that perpetuates systematic and institutionalized inequalities. This double disadvantage constitutes a form of “hobbling” (Justice 2021), a social process that restricts demographically targeted children's right to a public education, limits their social mobility, disempowers communities subjugated by race and class (Weaver and Geller 2019), and sustains structural racism.
While administrative school district records allow us to create a unique longitudinal data set, these data lack detailed information on underlying mechanisms. We could not examine the two key processes—institutional trust and trauma—that link long-term exposure to neighborhood policing to high school graduation. Future research should address this limitation with a specific focus on cumulative exposure to policing.
Our research echoes the notion that residential environments have an important effect on children's life chances (Chetty et al. 2014; Sampson 2012). We show that neighborhood policing can be an important contributor to the negative effects of growing up in a disadvantaged neighborhood and highlight policing practices as one of many dimensions through which residential environments can affect an individual's outcomes (Harding et al. 2010). In addition to considering how the absence of positive mechanisms, such as collective efficacy, contributes to the detrimental effects of neighborhoods on their residents' well-being, future research should also consider how the presence of negative mechanisms, such as systems avoidance and the erosion of trust in state institutions, disempowers their residents and shapes their perceptions of neighborhoods (Bell 2020).
Aside from focusing on disparities in and the effect of long-term exposure to neighborhood policing, this article uses novel gap-closing estimands (Lundberg 2021) to examine several counterfactual scenarios that help us understand how the racial/ethnic gap in high school graduation would change for a sample of students if exposure to neighborhood policing were equalized or solely based on neighborhood crime. This analysis is the first to assess whether neighborhood policing plays a meaningful role in explaining the Black–White and Latino–White gaps in high school graduation and whether changes in policing policy would reduce these gaps. The findings show that assigning a sample of Black and Latino students to the same level of neighborhood policing as White students would reduce the Black–White gap in high school graduation by 27.8% and the Latino–White gap by 17.5%. Alternatively, we show that if neighborhood policing was solely a function of violent crime, the Black–White gap would close by up to 10.2%, but only if the level of police stops is lower than at the peak of the SQF program.
From a scientific perspective, these findings indicate that neighborhood policing accounts for almost a third of the Black–White gap in high school graduation and to a smaller extent for the Latino–White gap. This assessment, however, is limited by the far-reaching and sometimes implausible nature of claims about a radically different world. From a policy perspective, the gap-closing estimands portray the expected disparities in high school graduation under a largely race-neutral allocation of police resources and suggest that such an intervention would make a meaningful but not large difference for such disparities. Overall, gap-closing estimands are a novel and innovative way to explore the role of policing policy for an important and consequential aspect of racial/ethnic inequalities—the gap in high school graduation rates. Building on Lundberg's work (2021), our article presents one of the first applications of this approach to a concrete applied problem that is relevant for population science and beyond.
## Acknowledgments
For helpful comments and advice, we thank Xiang Zhou, Ian Lundberg, and David Brady. The study was approved by the institutional review board at Harvard University (IRB Protocol ID IRB18-1584). Replication code is available at https://osf.io/6br57/. This research was funded by National Science Foundation grant 1850666.
## Notes
1
Less than 1% of the sample (2,941 students or 0.869%) drop out of school before the end of the period during which we measure cumulative exposure to police stops. In supplementary analysis, we exclude these students from the analytic sample. The results are substantively the same as the findings presented here.
2
Table A2 in the online appendix reports the regression results for a continuous (logged) measure of cumulative exposure. Converting continuous treatment variables into categorical variables can be problematic if the distribution of students within quintiles differs across groups. The results in Table A2 alleviate these concerns. They show a similar pattern, although the results provide clearer evidence for a potential negative effect on White students.
3
We also include drug and weapons crimes as time-varying covariates when estimating the effect of pedestrian stops and misdemeanor arrests on the subset of cohorts for which we observe these variables across the observation period. These results are substantively identical to the more parsimonious models and are not included.
4
Lundberg (2021) also proposed a doubly robust estimator that combines an estimator based on predicted outcomes like the one discussed here with an estimator based on predicted treatment probabilities. The doubly robust estimator is more robust to certain misspecifications. Our analysis relies on the predicted outcomes approach using the g-formula because it directly builds on our estimation strategy that is particularly suited for settings with time-varying treatment and controls.
5
Note that the descriptive statistics presented here focus on neighborhood police stops during the entire school year and not just the fall term as the measure used in the regression analysis to ensure a clear temporal order between the time-varying treatment and confounder. Table 1 presents descriptive statistics for the measures used in the analysis.
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| 2023-01-30T03:54:33 |
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https://www.usgs.gov/center-news/volcano-watch-volcanoes-are-a-part-breathing-earth
|
# Volcano Watch — Volcanoes are a part of the "breathing" of the Earth
Release Date:
One evening a couple of weeks ago, the summit of Kilauea began to deform at an impressive rate. Although the ground tilt and associated tremor caused by magma moving beneath the caldera was not humanly perceptible, sensitive instruments let us know that something unusual was up.
A couple of hours later, those of us here at HVO who study volcanic gases were found carefully picking our way back to the trailhead from our favorite Halemaumau sampling sites through the dark and murk of a near white-out. Our goal for the rest of the evening was to analyze the gas samples we collected, looking for, among other things, a possible change in the amount of carbon dioxide emitted from Kilauea by comparing these results with those of the previous day.
Carbon dioxide, CO2, is the gas we exhale and the gas that bubbles out of soda, beer, and even champagne when it's uncorked. It's also at the heart of the global warming debate.
Although nearly tasteless and odorless at low concentration, atmospheric CO2 monitoring was long ago recognized as a purposeful way to watch the Earth "breathe." In the late 1950s, researchers began doing just that. They chose Hawaii to site the instrumentation, because the island's remote location was devoid of large local forms of pollution that might bias the data.
Forty-three years later, Mauna Loa Observatory, part of the Department of Commerce, hosts the longest continuous atmospheric CO2 database on the planet. Great care has been taken to ensure that the data are globally representative.
No matter where you stand on the global warming issue, one particular conclusion from these data is irresistible: Carbon dioxide levels in the atmosphere have increased over 15 percent since 1958. This "modern" database can be combined with studies of CO2 trapped in polar ice cores, where CO2 concentrations are literally frozen in time. Together, the data suggest that although concentrations ranged widely during 400,000 years of ice core record, the recent high levels of atmospheric CO2 are unprecedented.
The ice core data show that CO2 has been part of the atmosphere for at least the last 400,000 years, and studies in Hawai'i and elsewhere indicate that volcanoes played a profound role in the formation of Earth's atmosphere during the previous 4-plus billion years. Visualize Kilauea's magma chamber as a leaky balloon being filled from below. The material entering the balloon is a bubbly mixture of magma and gas coming up a narrow pipe-shaped conduit from the earth's mantle.
The pressure at the depth of the mantle is enormous, more than 28 million kilograms per square meter (40,000 pounds per square inch), owing to the weight of solid and liquid rock resting upon it. It's like being at the bottom of a swimming pool, only the pool is 10,000 meters (33,000 feet) instead of 4 meters (13 feet) deep, and it's filled with dense liquid rock instead of merely water. As magma ascends from the mantle and enters the chamber "balloon," pressure becomes lower because the chamber is centered a scant 4 km (2.5 miles) beneath the summit of the volcano. This lower pressure allows some of the gas, notably CO2, to bubble out in the same way uncorking a champagne bottle does.
Much of the buoyant CO2 floats to the top of the chamber and leaks out through the roof, escaping to the atmosphere through surface vents and fumaroles-more than 8,000 tonnes each day. The magma, however, almost continuously leaks out through the side and is currently being erupted at Puu Oo. Sudden changes of magma supply or eruption rate, or of plumbing, such as those detected two weeks ago, accompany pressure changes within the chamber.
On a good day, those of us who study gases record these events as more or less spectacular changes in gas emissions. Although our sampling results from two weeks ago were of the less spectacular variety, these and other studies have taught us much about how volcanoes work. They have enhanced our understanding of how emissions from a very active volcano contribute to the breathing of the earth.
### Volcano Activity Update
Eruptive activity of Kilauea Volcano continued unabated and effusively at the Puu Oo vent during the past week. Lava extruded sporadically from several vents in the crater of Puu Oo as well as from the Episode 55 pit and Puka Nui, two small craters at the southwest base of the cone. Bright glow persists over the "rootless" shield area, where short flows emanate from overflows of the perched ponds and from leaks at the base of the shields. No surface flows were observed on Pulama pali or on the fan at the base of the pali. There are no ocean entries.
One earthquake was reported felt during the week ending on April 18. A resident of Leilani Estates subdivision felt a magnitude-2.7 shock at 10:32 a.m. on April 16. The earthquake was located about 3 km (1.8 miles) northeast of Pu`ulena Crater at a very shallow depth.
| 2020-08-04T03:48:11 |
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|
http://indico.vecc.gov.in/conferenceDisplay.py/openMenu%3FcurrentURL=http%253A%252F%252Findico.vecc.gov.in%252Findico%252FcontributionDisplay.py%253FcontribId%253D88%2526confId%253D1&confId=1.html
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# ICPAQGP-2010
5-10 December 2010
6th International Conference on Physics and Astrophysics of Quark Gluon Plasma (ICPAQGP 2010)
Home > Timetable > Contribution details
Effect of running coupling on photons from jet - plasma interaction in relativistic heavy ion collisions
Content: We discuss the role of collisional energy loss on high $p_T$ photon data measured by PHENIX collaboration by calculating photon yield in jet-plasma interaction. The phase space distribution of the participating jet is dynamically evolved by solving Fokker-Planck equation. We treat the strong coupling constant ($\alpha_s$) as function of momentum and temperature while calculating the drag and diffusion coefficients. It is observed that the quenching factor is substantially modified as compared to the case when $\alpha_s$ is taken as constant. It is shown that the data is reasonably well reproduced when contributions from all the relevant sources are taken into account. Predictions at higher beam energies relevant for LHC experiment have been made.
Id: 88
Place:
Room: Main Auditorium
Starting date:
--not yet scheduled--
Duration: 00'
Primary Authors: Mrs. BHATTACHARYA, Lusaka (Saha Institute of Nuclear Physics)
Mr. MANDAL, Mahatsab (Saha Institute of Nuclear Physics)
Presenters: Mrs. BHATTACHARYA, Lusaka
| 2021-10-24T19:21:36 |
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https://pdglive.lbl.gov/DataBlock.action?node=S070T0&home=BXXX045
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${{\boldsymbol \Xi}_{{b}}^{0}}$ MEAN LIFE
OUR EVALUATION'' is an average using rescaled values of the data listed below. The average and rescaling were performed by the Heavy Flavor Averaging Group (HFLAV) and are described at https://hflav.web.cern.ch/. The averaging/rescaling procedure takes into account correlations between the measurements and asymmetric lifetime errors.
${{\boldsymbol \Xi}_{{b}}^{0}}$ MEAN LIFE
VALUE ($10^{-12}$ s) DOCUMENT ID TECN COMMENT
$\bf{ 1.480 \pm0.030}$ OUR EVALUATION
$1.477$ $\pm0.026$ $\pm0.019$ 1
2014 Z
LHCB ${{\mathit p}}{{\mathit p}}$ at 7, 8 TeV
1 Uses ${{\mathit \Xi}_{{b}}^{0}}$ $\rightarrow$ ${{\mathit \Xi}_{{c}}^{+}}{{\mathit \pi}^{-}}$ and ${{\mathit \Xi}_{{c}}^{+}}$ $\rightarrow$ ${{\mathit p}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}$ decays. The measurement comes from the value of relative lifetime of ${{\mathit \Xi}_{{b}}^{0}}$ to ${{\mathit \Lambda}_{{b}}^{0}}$.
References:
AAIJ 2014Z
PRL 113 032001 Precision Measurement of the Mass and Lifetime of the ${{\mathit \Xi}_{{b}}^{0}}$ Baryon
| 2022-01-24T03:32:51 |
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http://dergipark.gov.tr/ijot/issue/26363/277770
|
Yıl 2016, Cilt 19, Sayı 4, Sayfalar 198 - 204 2016-12-01
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## Comprehensive study on the role of eco-friendly working fluid properties on ORC performances
#### Jahar Sarkar [1]
##### 231 228
In the present study, the effects of various low-GWP fluid properties on organic Rankine cycle (ORC) performances are examined for low grade heat sources and an attempt is made to prepare a general guideline to compare working fluids for ORC based on their basic properties. Theoretical study on ORC is conducted to study the effects of various fluid properties on net power generation, thermal efficiency, turbo-machinery and heat exchanger compactness. The considered eco-friendly working fluids for ORC were shortlisted based on operational, environmental and safety criteria. Performance comparison between selected working fluids shows that ammonia is the best fluid in terms of net power generation and compactness of turbo-machineries, whereas n-Pentane is the best fluid in terms of thermal efficiency and heat exchangers compactness. Study shows that the molar mass, normal boiling point temperature, critical temperature and phase diagram characteristics have significant effect on cycle performance indexes. However, the effect of properties does not show any common criteria for best in terms of all performance indexes. Present study summarizes the required fluid properties to get individually best for all performance indexes, which will be useful for fluid comparison and selection for certain design target.
Organic Rankine cycle, Environmental Safety; Fluid properties; Performance
Konular Regular Original Research Article Yazar: Jahar Sarkar
Bibtex @ { ijot277770, journal = {International Journal of Thermodynamics}, issn = {1301-9724}, eissn = {2146-1511}, address = {Yaşar DEMİREL}, year = {2016}, volume = {19}, pages = {198 - 204}, doi = {10.5541/eoguijt.277770}, title = {Comprehensive study on the role of eco-friendly working fluid properties on ORC performances}, key = {cite}, author = {Sarkar, Jahar} } APA Sarkar, J . (2016). Comprehensive study on the role of eco-friendly working fluid properties on ORC performances. International Journal of Thermodynamics, 19 (4), 198-204. Retrieved from http://dergipark.gov.tr/ijot/issue/26363/277770 MLA Sarkar, J . "Comprehensive study on the role of eco-friendly working fluid properties on ORC performances". International Journal of Thermodynamics 19 (2016): 198-204 Chicago Sarkar, J . "Comprehensive study on the role of eco-friendly working fluid properties on ORC performances". International Journal of Thermodynamics 19 (2016): 198-204 RIS TY - JOUR T1 - Comprehensive study on the role of eco-friendly working fluid properties on ORC performances AU - Jahar Sarkar Y1 - 2016 PY - 2016 N1 - DO - T2 - International Journal of Thermodynamics JF - Journal JO - JOR SP - 198 EP - 204 VL - 19 IS - 4 SN - 1301-9724-2146-1511 M3 - UR - Y2 - 2019 ER - EndNote %0 International Journal of Thermodynamics Comprehensive study on the role of eco-friendly working fluid properties on ORC performances %A Jahar Sarkar %T Comprehensive study on the role of eco-friendly working fluid properties on ORC performances %D 2016 %J International Journal of Thermodynamics %P 1301-9724-2146-1511 %V 19 %N 4 %R %U ISNAD Sarkar, Jahar . "Comprehensive study on the role of eco-friendly working fluid properties on ORC performances". International Journal of Thermodynamics 19 / 4 (Aralık 2016): 198-204.
| 2019-03-18T13:41:33 |
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http://apo.ansto.gov.au/dspace/handle/10238/3926
|
Please use this identifier to cite or link to this item: http://apo.ansto.gov.au/dspace/handle/10238/3926
Title: Critical magnetic transition in TbNi2Mn-magnetization and Mössbauer spectroscopy Authors: Wang, JLCampbell, SJKennedy, SJZeng, RDou, SXWu, GH Keywords: SpectroscopyMagnetizationRare EarthsX-ray DiffractionInorganic CompoundsMagnetic Susceptibility Issue Date: 1-Jun-2011 Publisher: IOP Publishing LTD Citation: Wang, J.L., Campbell, S.J., Kennedy, S.J., Zeng, R., Dou, S.X., Wu, G.H. (2011). Critical magnetic transition in TbNi2Mn-magnetization and Mössbauer spectroscopy. Journal of Physics: Condensed Matter, 23(21), Art. No. 216002. Abstract: The structural and magnetic properties of the TbNi2Mnx series (0.9 ≤ x ≤ 1.10) have been investigated using x-ray diffraction, field- and temperature-dependent AC magnetic susceptibility, DC magnetization (5–340 K; 0–5 T) and 57Fe Mössbauer spectroscopy (5–300 K). TbNi2Mnx crystallizes in the MgCu2-type structure (space group Fd\bar {3}m ). The additional contributions to the magnetic energy terms from transition-metal–transition-metal interactions (T–T) and rare-earth–transition-metal interactions (R–T) in RNi2Mn compounds contribute to their increased magnetic ordering temperatures compared with RNi2 and RMn2. Both the lattice constant a and the Curie temperature TC exhibit maximal values at the x = 1 composition indicating strong magnetostructural coupling. Analyses of the AC magnetic susceptibility and DC magnetization data of TbNi2Mn around the Curie temperature TC = 147 K confirm that the magnetic transition is second order with critical exponents β = 0.77 ± 0.12, γ = 1.09 ± 0.07 and δ = 2.51 ± 0.06. These exponents establish that the magnetic interactions in TbNi2Mn are long range despite mixed occupancies of Tb and Mn atoms at the 8a site and vacancies. The magnetic entropy − ΔSM around TC is proportional to (μ0H/TC)2/3 in agreement with the critical magnetic analyses. The Mössbauer spectra above TC are fitted by two sub-spectra in agreement with refinement of the x-ray data while below TC three sub-spectra are required to represent the three inequivalent local magnetic environments.(c) 2011 IOP Publishing LTD URI: http://dx.doi.org/10.1088/0953-8984/23/21/216002http://apo.ansto.gov.au/dspace/handle/10238/3926 ISSN: 0953-8984 Appears in Collections: Journal Articles
Files in This Item: There are no files associated with this item.
Items in APO are protected by copyright, with all rights reserved, unless otherwise indicated.
DSpace Software Copyright © 2002-2010 Duraspace - Feedback
| 2014-04-17T19:14:12 |
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https://gitlab.software.imdea.org/alessandra.gorla/imdea-se-bib/-/blame/51249692110f18a7dbda05dd2ef5e4ef7d4768c2/README.md
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Alessandra Gorla committed Feb 23, 2018 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 imdea-se-bib: collection of BibTeX bibliography files ====================================================== This project is a fork of forked of the plume-bib project from Michael D. Ernst: https://github.com/mernst/plume-bib To obtain the bibliographies, run: git clone https://gitlab.software.imdea.org/alessandra.gorla/imdea-se-bib.git This is a set of BibTeX bibliographies. You can re-use them rather than having to re-type or download. Re-typing or downloading bibliography entries is a notorious source of errors. For example, even the ACM Digital Library often has incorrect capitalization, or gives a SIGPLAN Notices reference when the conference proceedings would be more appropriate. Here are some other features: * Short and long versions of names, locations, and dates for conferences, journals, etc. The short (abbreviated) version is convenient if your paper is nearing its page limit. Changing between the two versions only requires a tiny change to your LaTeX file (see below), and no changes to any bib files. * Consistent naming convention for citation keys: last name of first author, followed by last initial of each other author, followed by year. This makes the citation more recognizable in your LaTeX source, and avoids duplicates. * Searchable via the bibfind tool. For instance, bibfind keyword1 keyword2 displays all the bibliographies with all the keywords, either in the entries in the comments. (This is why there are no blank lines in the comments that abut some bib entries: the search tool considers each blank line to start a new entry. We may lift that restriction in the future.) You can obtain the bibliographies by running the command git clone https://gitlab.software.imdea.org/alessandra.gorla/imdea-se-bib.git but you do not need to -- see below for how to set your build system to automatically obtain and/or update a copy. You can also set the IMDEASEBIB environment variable to the location of your clone (usually a directory named bib), so that you will have just one clone rather than one for each paper you write. USAGE ----- To choose the abbreviated (short) or unabbreviated (long) version of the bibliography strings, use one of these commands in your LaTeX file: 53 54 55 56 57 58 59 60 61 62 Most complete option. It will use full strings for journals (bibstring-unabbrev) and full proceedings info for conferences (crossrefs). \bibliography{bibstring-unabbrev,...,crossrefs} No month and address option. It will use short strings for journals (bibstring-abbrev) and full proceedings info for conferences, but omitting months and addresses. (crossrefs-abbrev). Alessandra Gorla committed Feb 23, 2018 63 \bibliography{bibstring-abbrev,...,crossrefs-abbrev} 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 Abbreviations option. It will use short strings for journals (bibstring-abbrev) and will shorten some words in the proceedings info for conferences (e.g. Proceedings --> Proc., Conference --> Conf.) as in crossrefs-abbrevv. \bibliography{bibstring-abbrev,...,crossrefs-abbrevv} Super-compressed option. It will use short strings for journals (bibstring-abbrev) and will shorten proceedings for conferences leaving only acronyms. (e.g. ICSE 2017: Proceedings of the International Conference...--> ICSE 2017), as in crossrefs-super-abbrev. \bibliography{bibstring-abbrev,...,crossrefs-super-abbrev} Alessandra Gorla committed Feb 23, 2018 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 When using the bibliographies, add near the top of your LaTeX document: \usepackage{url} This defines the \url command used in the bibliographies. To make URLs use a slightly narrower font (the regular tt font is very wide), use: \usepackage{pslatex} or, to use a smaller font, use: \usepackage{relsize} \def\UrlFont{\smaller\ttfamily} EDITING AND ADDING ENTRIES -------------------------- Changes, corrections, and additions are welcome. When adding new bibliography entries, please create an entry in crossrefs.bib for conferences, and create bibliography strings in bibstring-master for journal/institution names and abbreviations. For consistency, please start each new bibliography entry with "@" in the first column, and end the entry with "}" on its own line. If you make changes but you lack write access to the Git repository then please submit a pull request, or email a patch (a diff file) with your changes to Alessandra Gorla . SETUP -- if you use a Makefile to process your paper ---------------------------------------------------- 1. Add "bib" as a dependency for the rule that calls bibtex; for example, make "bib" a dependency for the myfile.bbl target. If no rule calls bibtex, you can skip this step. 2. Add "bib-update" as a dependency of your default target (such as "all"). 3. Add the following rules to your Makefile. export BIBINPUTS ?= .:bib bib: ifdef IMDEASEBIB ln -s ${IMDEASEBIB}$@ else git clone https://gitlab.software.imdea.org/alessandra.gorla/imdea-se-bib.git $@ endif .PHONY: bib-update bib-update: bib # Even if this command fails, it does not terminate the make job. # However, to skip it, invoke make as: make NOGIT=1 ... ifndef NOGIT -(cd bib && git pull && make) endif SETUP -- non-Makefile version ----------------------------- If you have previously cloned plume-bib and set the IMDEASEBIB environment variable, there is nothing to do. Otherwise, run this command: cd; git clone https://gitlab.software.imdea.org/alessandra.gorla/imdea-se-bib.git bib Then, set the IMDEASEBIB environment variable to$HOME/bib and add the "bib" directory to your BIBINPUTS environment variable. bash syntax: export IMDEASEBIB=$HOME/bib export BIBINPUTS=.:${IMDEASEBIB}:..: SETUP -- miscellaneous details ------------------------------ For the bibfind command, see https://github.com/mernst/uwisdom/blob/wiki/README.adoc . The bibfind command uses the bibroot file in the imdea-se-bib directory. If you wish to have only a single copy of the bibliographies on your computer, you can clone the repository just once and set the IMDEASEBIB environment variable. Then your Makefile will create (or you can make by hand) a symbolic link from any directories where you are writing a paper. Note for miktex users: The bibtex that is supplied with miktex (the popular Windows implementation) does not support the BIBINPUTS variable. You need to modify the miktex configuration. In file ...\miktex\config\miktex.ini, edit this entry: Input Dirs=searchpath (search path for BibTeX input files -- both databases and style files). INVOKING BIBTEX: crossref and -min-crossrefs=9999 ------------------------------------------------- imdea-se-bib's .bib files use @crossref. To avoid outut like [1] Brun et al. Paper title. In [2]. [2] Proceedings of ESEC/FSE 2011. Szeged, Hungary, Sep. 7--9, 2011. you need to pass the -min-crossrefs=9999 command-line option to BibTeX; for example: bibtex -min-crossrefs=9999 mypaper LICENSE ------- Uses the Creative Commons Attribution ("CC-BY") license. See file LICENSE.
| 2022-05-23T20:53:03 |
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https://arrow.fandom.com/wiki/User_talk:Chinkycandie
|
8,607 Pages
# Chinkycandie
## aka BichYu Ngu
0 Discussion posts
My favorite wikis
• I live in Australia
• I was born on April 29
• My occupation is IT Assistant
• I am Female
## Moderator Warning
I understand you were the target of a personal attack, but this:
"'No. You're being the insufferable person. You sound and write like a teen."
—(You)[src]
...is only perpetuating the situation.
Just don't. --Kir the Wizard (talk) 10:20, October 10, 2017 (UTC)
I don't normally have such childish discussions but all that person did was constantly call me stupid even if I was being rational and thinking maturely. Chinkycandie (talk) 10:41, October 10, 2017 (UTC)
## Images
Generally speaking, we use screenshots over promo still. Also, try naming images with a descriptive name. It's possible someone will overwrite the image with a completely different image since it's a generic name while that image is used for a specific section of a biography which would mess it up.TIMESHADE |Talk/Wall| - |C| 07:08, November 1, 2017 (UTC)
## Synopsis
Just so you know, you've been spelling "synopsis" as "sypnosis", which is wrong. An easy mistake to make, just letting you know. —MakeShift (talk page) 13:03, November 3, 2017 (UTC)
## Re:Subpage
It's been brought up before. However, such a scenario would just leave more pages to moderate and more places to vandalize. And it gets subjective what goes in the subpage and what goes on the main page.TIMESHADE |Talk/Wall| - |C| 09:10, November 6, 2017 (UTC)
Our wiki has a far larger user base, so it means more people edit and we have to moderate them to make sure they're up to standards, which ours needs to be high due to high viewer base. If anything, a way to solve the long page issue is what OuaT wiki does with expandable/collapseable sections.TIMESHADE |Talk/Wall| - |C| 00:13, November 8, 2017 (UTC)
## RE: Complimentary
Hey, thanks! Well, I started out as a user at this community, at the suggestion of User:Тостер, so I often read and comment on the blogs and threads. Plus, I kinda had to do this, due to my content mod duties, and if you have to read it, might as well say something, eh? --Kir the Wizard (talk) 13:50, November 7, 2017 (UTC)
## RE: Jack Moore
The guest stars in the infobox should only be those listed as such in the opening credits (and occasionally the one or two in the closing). Any others that aren't should be removed. As for on the season pages, that's free reign, cause Jack Moore is technically recurring. —MakeShift (talk page) 02:04, November 18, 2017 (UTC)
## Spoiler policy
Just like to point you to our spoiler policy. Because the costumes have only been on promotional material thus far, it's considered a spoiler as it has yet to appear in an aired episode. Feel free to add them back once we see the suits in an episode though.TIMESHADE |Talk/Wall| - |C| 03:39, January 10, 2018 (UTC)
## Totem bearer
Sounds great! But probably should only use it for people who successfully used it, as Ray failed to use the water totem.TIMESHADE |Talk/Wall| - |C| 06:54, April 6, 2018 (UTC)
Inmates category sounds great also.TIMESHADE |Talk/Wall| - |C| 16:03, April 6, 2018 (UTC)
## Just So You Know
I was editing from the mobile version of the wiki while I was updating Season 4 as the news started to roll in. Take youre attitude somewhere else if youre gonna try and disrespect me.AtomicBombshell29 (talk)
## Infoboxes
Please keep infoboxes in the order they're listed on their template pages, not some jumbled up mess. We like to keep it that way as it makes things easier to edit across the board, so having the variables in some random order just confuses matters. —MakeShift (talk page) 13:30, January 22, 2019 (UTC)
## Information
On series regulars: I'll add them to the Portal when they are actually listed in the credits (we've had announcements that Matt Ryan would be in the main cast, but he was only credited as special appearance by, at least so far). On other points: that can be added in respective articles by anyone.--Kir the Wizard (talk) 20:54, March 18, 2019 (UTC)
By the way, it is normal for these pages to be locked until closer to the season actually starting. $\int$ IHH dt 11:36, Apr 01, 2020 (UTC)
## Removing references
Just a heads up, while I know you were removing references on the "Fadeout" page as most weren't needed anymore, but a few of them that referenced things not covered in the episode should still keep the citation, like Amell and Ramsey getting their respective endings. —MakeShift (talk page) 04:58, January 29, 2020 (UTC)
Community content is available under CC-BY-SA unless otherwise noted.
| 2020-04-01T11:36:03 |
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https://pos.sissa.it/326/049/
|
Volume 326 - The International Conference on B-Physics at Frontier Machines (BEAUTY2018) - Session: b->s penguin decays
Angular analyses of $b\to s \ell \ell$ modes at LHCb
E. Smith* on behalf of the LHCb collaboration
*corresponding author
Full text: pdf
Pre-published on: 2018 October 25
Published on: 2018 October 30
Abstract
The study of rare decays mediated via $b\to s ll$ transitions allows for new physics searches which are sensitive to mass scales up to $\mathcal{O}$(100) TeV. Sensitivity to new physics can be increased via angular analyses, as angles involve ratios of observables, causing angular coefficents to have reduced theoretical uncertainties. There continue to be significant tensions with the Standard Model across a range of experimental observables associated with $b\to sll$ decays, including in angular observables. These proceedings outline the latest analyses involving this class of decays at LHCb, with a focus on angular analyses and modes involving muons
DOI: https://doi.org/10.22323/1.326.0049
Open Access
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
| 2020-06-03T17:22:34 |
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http://dlmf.nist.gov/19.26
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## §19.26(i) General Formulas
In this subsection, and also §§19.26(ii) and 19.26(iii), we assume that are positive, except that at most one of can be 0.
where and
19.26.2
with corresponding equations for and obtained by permuting . Also,
where
with and obtained by permuting , , and . (Note that .) Equivalent forms of (19.26.2) are given by
and
Also,
where
19.26.10
Lastly,
where , , , and
19.26.12
Equivalent forms of (19.26.11) are given by
where for , except that can be 0, and
where
## §19.26(iii) Duplication Formulas
The equations inverse to and the two other equations obtained by permuting (see (19.26.19)) are
and two similar equations obtained by exchanging with (and with ), or with (and with ).
| 2013-05-22T16:31:26 |
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https://par.nsf.gov/biblio/10273413-einstein-home-discovery-gamma-ray-millisecond-pulsar-psr-j20395617-confirms-its-predicted-redback-nature
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Einstein@Home discovery of the gamma-ray millisecond pulsar PSR J2039–5617 confirms its predicted redback nature
ABSTRACT The Fermi Large Area Telescope gamma-ray source 3FGL J2039.6–5618 contains a periodic optical and X-ray source that was predicted to be a ‘redback’ millisecond pulsar (MSP) binary system. However, the conclusive identification required the detection of pulsations from the putative MSP. To better constrain the orbital parameters for a directed search for gamma-ray pulsations, we obtained new optical light curves in 2017 and 2018, which revealed long-term variability from the companion star. The resulting orbital parameter constraints were used to perform a targeted gamma-ray pulsation search using the Einstein@Home-distributed volunteer computing system. This search discovered pulsations with a period of 2.65 ms, confirming the source as a binary MSP now known as PSR J2039–5617. Optical light-curve modelling is complicated, and likely biased, by asymmetric heating on the companion star and long-term variability, but we find an inclination i ≳ 60°, for a low pulsar mass between $1.1\, \mathrm{M}_{\odot } \lt M_{\rm psr} \lt$ 1.6 M⊙, and a companion mass of 0.15–$0.22\, \mathrm{M}_{\odot }$, confirming the redback classification. Timing the gamma-ray pulsations also revealed significant variability in the orbital period, which we find to be consistent with quadrupole moment variations in the companion star, suggestive of convective activity. We also find that more »
Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
Award ID(s):
Publication Date:
NSF-PAR ID:
10273413
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
502
Issue:
1
Page Range or eLocation-ID:
915 to 934
ISSN:
0035-8711
1. ABSTRACT We report observed and derived timing parameters for three millisecond pulsars (MSPs) from observations collected with the Parkes 64-m telescope, Murriyang. The pulsars were found during reprocessing of archival survey data by Mickaliger et al. One of the new pulsars (PSR J1546–5925) has a spin period P = 7.8 ms and is isolated. The other two (PSR J0921–5202 with P = 9.7 ms and PSR J1146–6610 with P = 3.7 ms) are in binary systems around low-mass (${\gt}0.2\, {\rm M}_{\odot }$) companions. Their respective orbital periods are 38.2 and 62.8 d. While PSR J0921–5202 has a low orbital eccentricity e = 1.3 × 10−5, in keeping with many other Galactic MSPs, PSR J1146–6610 has a significantly larger eccentricity, e = 7.4 × 10−3. This makes it a likely member of a group of eccentric MSP–helium white dwarf binary systems in the Galactic disc whose formation is poorly understood. Two of the pulsars are co-located with previously unidentified point sources discovered with the Fermi satellite’s Large Area Telescope, but no γ-ray pulsations have been detected, likely due to their low spin-down powers. We also show that, particularly in terms of orbital diversity, the current sample of MSPs is far from complete and is subject to a number of selection biases.
3. ABSTRACT The fraction of stars that are in binaries or triples at the time of stellar death and the fraction of these systems that survive the supernova explosion are crucial constraints for evolution models and predictions for gravitational wave source populations. These fractions are also subject to direct observational determination. Here, we search 10 supernova remnants containing compact objects with proper motions for unbound binaries or triples using Gaia EDR3 and new statistical methods and tests for false positives. We confirm the one known example of an unbound binary, HD 37424 in G180.0−01.7, and find no other examples. Combining this with our previous searches for bound and unbound binaries, and assuming no bias in favour of finding interacting binaries, we find that 72.0 per cent (52.2–86.4 per cent, 90 per cent confidence) of supernova producing neutron stars are not binaries at the time of explosion, 13.9 per cent (5.4–27.2 per cent) produce bound binaries, and 12.5 per cent (2.8–31.3 per cent) produce unbound binaries. With a strong bias in favour of finding interacting binaries, the medians shift to 76.0 per cent were not binaries at death, 9.5 per cent leave bound binaries, and 13.2 per cent leave unbound binaries. Of explosions that do not leave binaries, ${\lt}18.9{{\ \rm per\ cent}}$ can be fully unbound triples. These limits are conservatively for \$M\gtmore »
| 2022-10-05T18:30:49 |
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|
http://www.ck12.org/book/CK-12-Chemistry-Second-Edition/r8/section/13.3/
|
<meta http-equiv="refresh" content="1; url=/nojavascript/">
You are reading an older version of this FlexBook® textbook: CK-12 Chemistry - Second Edition Go to the latest version.
13.3: Types of Reactions
Difficulty Level: At Grade Created by: CK-12
Lesson Objectives
The student will:
• describe what is occurring in synthesis, decomposition, single replacement, double replacement, and combustion reactions.
• classify a chemical reaction as a synthesis, decomposition, single replacement, double replacement, or a combustion reaction.
• predict the products of simple reactions.
Vocabulary
• combustion reaction
• decomposition reaction
• double replacement reaction
• hydrocarbon
• single replacement reaction
• synthesis reaction
Introduction
Chemical reactions are classified into types to help us analyze them and to help us predict what the products of the reaction will be. The five major types of chemical reactions are synthesis, decomposition, single replacement, double replacement, and combustion.
Synthesis Reactions
A synthesis reaction is one in which two or more reactants combine to make one product. The general equation for a synthesis reaction is:
$A + B \rightarrow AB$
Synthesis reactions occur as a result of two or more simpler elements or molecules combining to form a more complex molecule. We can always identify a synthesis reaction because there is only one product. If you are given elemental reactants and told that the reaction is a synthesis reaction, you should be able to predict the products. For example, consider the equation below. Two elements (hydrogen and oxygen) combine to form one product (water).
$2 \ \text{H}_{2(g)} + \text{O}_{2(g)} \rightarrow 2 \ \text{H}_2\text{O}_{(l)}$
You should also be able to write the chemical equation for a synthesis reaction if you are given a product by picking out its elements and writing the equation. As a result, we can write the synthesis reaction for sodium chloride just by knowing the elements that are present in the product.
$2 \ \text{Na}_{(s)} + \text{Cl}_{2(g)} \rightarrow 2 \ \text{NaCl}_{(s)}$
Example:
1. Write the chemical equation for the synthesis reaction of silver bromide, $\text{AgBr}$.
2. Predict the products for the following reaction: $\text{CO}_{2(g)} + \text{H}_2\text{O}_{(l)}$.
3. Predict the products for the following reaction: $\text{Li}_2\text{O}_{(s)} + \text{CO}_{2(g)}$.
Solution:
1. $2 \ \text{Ag}_{(s)} + \text{Br}_{2(l)} \rightarrow 2 \ \text{AgBr}_{(s)}$
2. $\text{CO}_{2(g)} + \text{H}_2\text{O}_{(l)} \rightarrow \text{H}_2\text{CO}_{3(aq)}$
3. $\text{Li}_2\text{O}_{(s)} + \text{CO}_{2(g)} \rightarrow \text{Li}_2\text{CO}_{3(s)}$
Decomposition Reactions
When one type of reactant breaks down to form two or more products, we have a decomposition reaction. The best way to remember a decomposition reaction is that for all reactions of this type, there is only one reactant. The general equation for a decomposition reaction is:
$AB \rightarrow A + B$
Look at the equation below for an example of a decomposition reaction. In this reaction, ammonium nitrate breaks down to form dinitrogen oxide and water.
$\text{NH}_4\text{NO}_{3(s)} \rightarrow \text{N}_2\text{O}_{(g)} + 2 \text{H}_2\text{O}_{(g)}$
Notice that there is only one reactant, $\text{NH}_4\text{NO}_3$, on the left of the arrow and that there is more than one on the right side of the arrow. This is the exact opposite of a synthesis reaction.
When studying decomposition reactions, we can predict the reactants in a similar manner as we did for synthesis reactions. Look at the formula for magnesium nitride, $\text{Mg}_3\text{N}_2$. What elements do you see in this formula? You see magnesium and nitrogen. Now we can write a decomposition reaction for magnesium nitride.
$\text{Mg}_3\text{N}_{2(s)} \rightarrow 3 \ \text{Mg}_{(s)} + \text{N}_{2(g)}$
Notice there is only one reactant.
Example:
Write the chemical equation for the decomposition of the following compounds into their individual elements:
1. $\text{Al}_2\text{O}_3$
2. $\text{Ag}_2\text{S}$
3. $\text{MgO}$
Solution:
1. $2 \ \text{Al}_2\text{O}_3 \rightarrow 4 \ \text{Al} + 3 \ \text{O}_2$
2. $\text{Ag}_2\text{S} \rightarrow 2 \ \text{Ag} + \text{S}$
3. $2 \ \text{MgO} \rightarrow 2 \ \text{Mg} + \text{O}_2$
Single Replacement Reactions
A third type of reaction is the single replacement reaction. In single replacement reactions, one element reacts with one compound to form products. The single element is said to replace an element in the compound when the products form, hence the name single replacement.
There are actually three different types of single replacement reactions: 1) the single element is a metal and replaces the metal in the second reactant, 2) the single element is a metal and replaces the hydrogen in the second reactant, which is always an acid, and 3) the single element is a nonmetal and replaces the nonmetal in the second reactant.
Replacement of a Metal with a Metal
In this section, we will focus on single replacement reactions where an elemental metal reactant replaces the metal (or the cation) of a second compound. The general equation for this reaction is:
$A + BC \rightarrow B + AC$
Consider the following example. Notice there is only one reactant that is an element and one reactant that is a compound.
$\text{Zn}_{(s)} + \text{Cu(NO}_3)_{2(aq)} \rightarrow \text{Zn(NO}_3)_{2(aq)} + \text{Cu}_{(s)}$
When studying single replacement reactions, we can predict reactants in a similar manner as we did for synthesis and decomposition reactions. Suppose that we know a single replacement reaction will occur between solid aluminum and solid iron(III) oxide.
$\text{Al}_{(s)} + \text{Fe}_2\text{O}_{3(s)}$
In order to predict the products, we need to know that aluminum will replace iron and form aluminum oxide. Aluminum has a charge of $+3$ (it is in Group 3A), and oxygen has a charge of $-2$ (it is in Group 6A). The compound formed between aluminum and oxygen, therefore, will be $\text{Al}_2\text{O}_{3(s)}$. Since iron is replaced in the compound by aluminum, the iron product will now be a single element. The unbalanced equation will be:
$\text{Al}_{(s)} + \text{Fe}_2\text{O}_{3(s)} \rightarrow \text{Al}_2\text{O}_{3(s)} + \text{Fe}_{(s)}$.
The balanced equation will be:
$2 \ \text{Al}_{(s)} + \text{Fe}_2\text{O}_{3(s)} \rightarrow \text{Al}_2\text{O}_{3(s)} + 2 \ \text{Fe}_{(s)}$
Example:
1. Write the chemical equation for the single replacement reaction between zinc solid and lead(II) nitrate solution to produce zinc nitrate solution and solid lead.
2. Predict the products for the following reaction: $\text{Fe} + \text{CuSO}_4$.
3. Predict the products for the following reaction: $\text{Al} + \text{CuCl}_2$.
Solution:
1. $\text{Zn}_{(s)} + \text{Pb(NO}_3)_{2(aq)} \rightarrow \text{Pb}_{(s)} + \text{Zn(NO}_3)_{2(aq)}$
2. $\text{Fe}_{(s)} + \text{CuSO}_{4(aq)} \rightarrow \text{Cu}_{(s)} + \text{FeSO}_{4(aq)}$
3. $2 \ \text{Al} + 3 \ \text{CuCl}_2 \rightarrow 3 \ \text{Cu} + 2 \ \text{AlCl}_3$
Replacement of Hydrogen with a Metal
These reactions are the same as those studied in the last section, except the compound in the reactant side of the equation is always an acid. Since you may not have studied acids yet, you should consider an acid to be a compound in which hydrogen is combined with an anion. Therefore, in this section, we will consider single replacement reactions where the element reactant replaces the hydrogen in the acid compound. The general reaction is:
$\mathrm{A} + 2 \ \mathrm{HX} \rightarrow \mathrm{AX}_2 + \mathrm{H}_2$
The chemical equation below is an example of this type of reaction:
$\text{Zn}_{(s)} + 2 \ \text{HBr}_{(aq)} \rightarrow \text{ZnCl}_{2(aq)} + \text{H}_{2(g)}$
When studying these single replacement reactions, we can predict reactants in a similar manner as we did for the other types of single replacement reactions. Look at the reaction below. Since $\text{HCl}$ is a compound that has hydrogen combined with an anion, it is an acid.
$\text{Mg}_{(s)} + 2 \text{HCl}_{(aq)}$
In order to predict the products, we need to know that magnesium will replace hydrogen and form magnesium chloride. Magnesium has a charge of $+2$ (it is in Group 2A), and chlorine has a charge of $-1$ (it is in group 7A). Therefore, the compound formed will be $\text{MgCl}_2$. The replaced hydrogen forms the product elemental hydrogen, $\text{H}_2$. After the products are determined, all that remains is to balance the equation.
$\text{Mg}_{(s)} + 2 \ \text{HCl}_{(aq)} \rightarrow \text{MgCl}_{2(s)} + \text{H}_{2(g)}$
Notice that one reactant is the element $\text{Mg}$ and one reactant is an acid compound. The $\text{Mg}$ has replaced the hydrogen in $\text{HCl}$ in the same manner as $\text{Zn}$ replaced the hydrogen in the $\text{HBr}$ in the example above.
Example:
1. Write the chemical equation for the single replacement reaction between iron solid and hydrochloric acid solution to produce iron(II) chloride solution and hydrogen gas.
2. Predict the products for the following reaction: $\text{Zn}_{(s)} + \text{H}_2\text{SO}_{4(aq)}$.
3. Predict the products for the following reaction: $\text{Al}_{(s)} + \text{HNO}_{3(aq)}$.
Solution:
1. $\text{Fe}_{(s)} + 2 \ \text{HCl}_{(aq)} \rightarrow \text{FeCl}_{2(aq)} + \text{H}_{2(g)}$
2. $\text{Zn}_{(s)} + \text{H}_2\text{SO}_{4(aq)} \rightarrow \text{ZnSO}_{4(aq)} + \text{H}_{2(g)}$
3. $2 \ \text{Al}_{(s)} + 6 \ \text{HNO}_{3(aq)} \rightarrow 2 \ \text{Al(NO}_3)_{3(aq)} + 3 \ \text{H}_{2(g)}$
Replacement of a Nonmetal with a Nonmetal
In this section, we will focus on the final type of single replacement reactions where the element reactant replaces the nonmetal (or the anion) in a compound. The general equation for this type of reaction is:
$A + BC \rightarrow C + BA$
Notice in the equation below that the chlorine replaced the iodine to produce solid iodine as a product. We can predict the products for these single replacement reactions in a similar manner as for all other single replacement reactions. The only difference here is that we have to remember that we are replacing the anion of the compound rather than the cation.
$\text{Cl}_{2(g)} + 2 \ \text{KI}_{(aq)} \rightarrow 2 \ \text{KCl}_{(aq)} + \text{I}_{2(s)}$
Look at the reaction between chlorine gas and sodium bromide shown below. This is an actual method for extracting bromine from ocean water found to contain sodium bromide. Can you complete the reaction?
$\text{Cl}_{2(g)} + \text{NaBr}_{(aq)} \rightarrow ?$
In order to predict the products of this reaction, we need to know that chlorine will replace bromine and form sodium chloride. Sodium has a charge of $+1$ (it is in Group 1A) and chlorine has a charge of $-1$ (it is in group 7A). The compound formed will be $\text{NaCl}$.
$\text{Cl}_{2(g)} + 2 \ \text{NaBr}_{(aq)} \rightarrow 2 \ \text{NaCl}_{(aq)} + \text{Br}_{2(l)}$
Notice, as with all of the other single replacement reactions, that the reactants include one element and one compound, and the products contain one element and one compound. This is the determining factor for identifying whether you have a single replacement reaction.
Example:
1. Write the chemical equation for the single replacement reaction between sodium iodide solution and liquid bromine to produce sodium bromide solution and solid iodine.
2. Predict the products for the following reaction: $\text{Br}_{2(aq)} + \text{KI}_{(aq)}$.
3. Predict the products for the following reaction: $\text{MgI}_{2(aq)} + \text{Cl}_{2(aq)}$.
Solution:
1. $2 \ \text{NaI}_{(aq)} + \text{Br}_{2(l)} \rightarrow 2 \ \text{NaBr}_{(aq)} + \text{I}_{2(s)}$
2. $\text{Br}_{2(aq)} + 2 \ \text{KI}_{(aq)} \rightarrow 2 \ \text{KBr}_{(aq)} + \text{I}_{2(s)}$
3. $\text{MgI}_{2(aq)} + \text{Cl}_{2(aq)} \rightarrow \text{MgCl}_{2(aq)} + \text{I}_{2(s)}$
Double Replacement
For double replacement reactions, two reactants will react by having the cations exchange places. The key to identifying this type of reaction is to recognize that it has two compounds as reactants. This type of reaction is more common than any of the others, and there are many different types of double replacement reactions. Some double replacement reactions are more common than others. For example, precipitation and neutralization reactions are two of the most common double replacement reactions. Precipitation reactions are ones where two aqueous reactants combine to form products where one of the products is an insoluble solid. A neutralization reaction is one where the two reactant compounds are an acid and a base and the two products are a salt and water.
Example:
The following is a precipitation reaction because $\text{AgCl}_{(s)}$ is formed.
$\text{AgNO}_{3(aq)} + \text{NaCl}_{(aq)} \rightarrow \text{AgCl}_{(s)} + \text{NaNO}_{3(aq)}$
The following is a neutralization reaction because the acid, $\text{H}_2\text{SO}_4$, is neutralized by the base, $\text{NaOH}$.
$2 \ \text{NaOH}_{(aq)} + \text{H}_2\text{SO}_{4(aq)} \rightarrow \text{Na}_2\text{SO}_{4(aq)} + 2 \ \text{H}_2\text{O}_{(l)}$
In order to write the products for a double displacement reaction, you must be able to determine the correct formulas for the new compounds. Consider this common laboratory experiment that involves the reaction between lead(II) nitrate and sodium iodide, both clear solutions. Here is the start of the reaction:
$\text{Pb(NO}_3)_{2(aq)} + \text{NaI}_{(aq)}$
Now, predict the products based on what you know about charges. We know that the cations exchange anions. We now have to look at the charges of each of the cations and anions to see what the products will be.
We should presume the charge of the lead will remain $+2$, and since iodine forms ions with a charge of $-1$, one product will be $\text{PbI}_2$. The other product will form between the sodium ion, whose charge is $+1$, and the nitrate ion, whose charge is $-1$. Therefore, the second product will be $\text{NaNO}_3$. Once the products are written in, the equation can be balanced.
$\text{Pb(NO}_3)_{2(aq)} + 2 \ \text{NaI}_{(aq)} \rightarrow \text{PbI}_{2(s)} + 2 \ \text{NaNO}_{3(aq)}$
The experiment produces a brilliant yellow precipitate. If you have use of a solubility table, it is easy to determine that the precipitate will be the lead(II) iodide. Even without a solubility table, knowing that lead compounds tend to precipitate and sodium compounds are always soluble, we would still be able to determine that the $\text{PbI}_2$ is the brilliant yellow precipitate.
Look at the reaction between acetic acid and barium hydroxide below.
$\text{HC}_2\text{H}_3\text{O}_{2(aq)} + \text{Ba(OH)}_{2(aq)} \rightarrow \text{?}$
Try to predict the products by having the cations exchange places and writing the correct formulas for the products formed.
$\text{HC}_2\text{H}_3\text{O}_{2(aq)} + \text{Ba(OH)}_{2(aq)} \rightarrow \text{Ba(C}_2\text{H}_3\text{O}_2)_{2(aq)} + \text{H}_2\text{O}_{(l)} \ \text{(not balanced)}$
Therefore, the final balanced equation will be:
$2 \ \text{HC}_2\text{H}_3\text{O}_{2(aq)} + \text{Ba(OH)}_{2(aq)} \rightarrow \text{Ba(C}_2\text{H}_3\text{O}_2)_{2(aq)} + 2 \ \text{H}_2\text{O}_{(l)} \ \text{(balanced)}$
This is an acid-base reaction yielding salt, barium acetate, and water. Notice that $\text{HOH}$ and $\text{H}_2\text{O}$ are the same.
Example:
1. Write a chemical equation for the double replacement reaction between calcium chloride solution and potassium hydroxide solution that produces potassium chloride solution and a precipitate of calcium hydroxide.
2. Predict the products for the following reaction: $\text{AgNO}_{3(aq)} + \text{NaCl}_{(aq)}$.
3. Predict the products for the following reaction: $\text{FeCl}_{3(aq)} + \text{KOH}_{(aq)}$.
Solution:
1. $\text{CaCl}_{2(aq)} + 2 \ \text{KOH}_{(aq)} \rightarrow \text{Ca(OH)}_{2(s)} + 2 \ \text{KCl}_{(aq)}$
2. $\text{AgNO}_{3(aq)} + \text{NaCl}_{(aq)} \rightarrow \text{AgCl}_{(s)} + \text{NaNO}_{3(aq)}$
3. $\text{FeCl}_{3(aq)} + 3 \ \text{KOH}_{(aq)} \rightarrow \text{Fe(OH)}_{3(s)} + 3 \ \text{KCl}_{(aq)}$
Combustion
A special type of single replacement reaction deserves some attention. These reactions are combustion reactions. In a combustion reaction, oxygen reacts with another substance to produce carbon dioxide and water.
In a particular branch of chemistry, known as organic chemistry, we study compounds known as hydrocarbons. A hydrocarbon is an organic substance consisting of only hydrogen and carbon. Combustion reactions usually have a hydrocarbon reacting with oxygen to produce $\text{CO}_2$ and $\text{H}_2\text{O}$. In other words, the only part that changes from one combustion reaction to the next is the actual hydrocarbon involved in the reaction. The general equation for this reaction is given below. Notice oxygen, carbon dioxide, and water are listed in the general equation to show that these reactants and products remain the same from combustion reaction to combustion reaction.
$\text{hydrocarbon} + \text{O}_{2(g)} \rightarrow \text{CO}_{2(g)} + \text{H}_2\text{O}_{(l)}$
Look at the the combustion reaction of octane, $\text{C}_8\text{H}_{18}$, shown below. Octane has 8 carbon atoms, hence the prefix “oct-.”
$2 \ \text{C}_8\text{H}_{18(l)} + 25 \ \text{O}_{2(g)} \rightarrow 16 \ \text{CO}_{2(g)} + 18 \ \text{H}_2\text{O}_{(l)}$
This reaction is referred to as complete combustion. Complete combustion reactions occur when there is enough oxygen to burn the entire hydrocarbon. This is why the only products are carbon dioxide and water.
Have you ever been in a lab and seen black soot appear on the bottom of a heated beaker? Or, have you ever seen the black puffs of smoke come out from the exhaust pipe of a car? If there is not enough oxygen, the result is an incomplete combustion reaction with $\text{CO}_{(g)}$ and $\text{C}_{(s)}$ (in the form of soot) also formed as products. Incomplete combustion reactions are actually quite dangerous because one of the products in the reaction is carbon monoxide, not carbon dioxide. Carbon monoxide is a gas that prevents oxygen from binding to the oxygen transport proteins in our blood cells. When the concentration of carbon monoxide in the blood becomes too high, not enough oxygen can be transported and the person can die.
Example:
Identify whether each of the following reactions are complete or incomplete combustions, and then balance the equation.
1. $\text{C}_7\text{H}_{16(l)} + \text{O}_{2(g)} \rightarrow \text{CO}_{2(g)} + \text{H}_2\text{O}_{(l)}$
2. $\text{C}_3\text{H}_{8(g)} + \text{O}_{2(g)} \rightarrow \text{CO}_{2(g)} + \text{H}_2\text{O}_{(l)}$
3. $\text{CH}_{4(g)} + \text{O}_{2(g)} \rightarrow \text{CO}_{(g)} + \text{H}_2\text{O}_{(l)}$
4. $\text{C}_5\text{H}_{12(l)} + \text{O}_{2(g)} \rightarrow \text{CO}_{2(g)} + \text{H}_2\text{O}_{(l)}$
5. $\text{C}_2\text{H}_{6(g)} + \text{O}_{2(g)} \rightarrow \text{CO}_{(g)} + \text{H}_2\text{O}_{(l)}$
Solution:
1. Complete; $\text{C}_7\text{H}_{16(l)} + 11 \ \text{O}_{2(g)} \rightarrow 7 \ \text{CO}_{2(g)} + 8 \ \text{H}_2\text{O}_{(l)}$
2. Complete; $\text{C}_3\text{H}_{8(g)} + 5 \ \text{O}_{2(g)} \rightarrow 3 \ \text{CO}_{2(g)} + 4 \ \text{H}_2\text{O}_{(l)}$
3. Incomplete; $2 \ \text{CH}_{4(g)} + 3 \ \text{O}_{2(g)} \rightarrow 2 \ \text{CO}_{(g)} + 4 \ \text{H}_2\text{O}_{(l)}$
4. Complete; $\text{C}_5\text{H}_{12(l)} + 8 \ \text{O}_{2(g)} \rightarrow 5 \ \text{CO}_{2(g)} + 6 \ \text{H}_2\text{O}_{(l)}$
5. Incomplete; $2 \ \text{C}_2\text{H}_{6(g)} + 5 \ \text{O}_{2(g)} \rightarrow 4 \ \text{CO}_{(g)} + 6 \ \text{H}_2\text{O}_{(l)}$
This video contains classroom demonstrations of several reaction types and then shows the balancing process for the reaction equations (3a) http://www.youtube.com/watch?v=4B8PFqbMNIw (8:40).
Lesson Summary
The Five Types of Chemical Reactions
Reaction Name Reaction Description
synthesis two or more reactants form one product.
decomposition one type of reactant forms two or more products.
single replacement one element reacts with one compound to form products.
double replacement two compounds act as reactants.
combustion a hydrocarbon reacts with oxygen gas.
The website below also reviews the different types of chemical reactions.
Review Questions
1. When balancing combustion reactions, did you notice a consistency relating to whether the number of carbons in the hydrocarbon was odd or even?
2. Distinguish between synthesis and decomposition reactions.
3. When dodecane, $\text{C}_{10}\text{H}_{22}$, burns in excess oxygen, the products would be:
1. $\text{CO}_2 + 2 \ \text{H}_2$
2. $\text{CO} + \text{H}_2\text{O}$
3. $\text{CO}_2 + \text{H}_2\text{O}$
4. $\text{CH}_4\text{O}_2$
4. In the decomposition of antimony trichloride, which of the following products and quantities will be found?
1. $\text{An} + \text{Cl}_2$
2. $2 \ \text{An} + 3 \ \text{Cl}_2$
3. $\text{Sb} + \text{Cl}_2$
4. $2 \ \text{Sb} + 3 \ \text{Cl}_2$
5. Acetylsalicylic acid (aspirin), $\text{C}_9\text{H}_8\text{O}_{4(s)}$, is produced by reacting acetic anhydride, $\text{C}_4\text{H}_6\text{O}_{3(l)}$, with salicylic acid, $\text{C}_7\text{H}_6\text{O}_{3(s)}$. The other product in the reaction is acetic acid, $\text{C}_2\text{H}_4\text{O}_{2(l)}$. Write the balanced chemical equation.
6. When iron rods are placed in liquid water, a reaction occurs. Hydrogen gas evolves from the container, and iron(III) oxide forms onto the iron rod.
1. Write a balanced chemical equation for the reaction.
2. What type of reaction is this?
7. A specific fertilizer is being made at an industrial plant nearby. The fertilizer is called a triple superphosphate and has a formula $\text{Ca}(\text{H}_2\text{PO}_4)_2$. It is made by treating sand and clay that contains phosphate with a calcium phosphate solution and phosphoric acid. The simplified reaction is calcium phosphate reacting with phosphoric acid to yield the superphosphate. Write the balanced chemical equation and name the type of reaction.
All images, unless otherwise stated, are created by the CK-12 Foundation and are under the Creative Commons license CC-BY-NC-SA.
Feb 23, 2012
Jan 07, 2015
| 2015-04-18T21:05:22 |
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https://www.aimsciences.org/article/doi/10.3934/proc.2015.0652
|
Article Contents
Article Contents
# On global dynamics in a multi-dimensional discrete map
• We derive preliminary results on global dynamics of the multi-dimensional discrete map $$F:\; (x_1,x_2,\dots,x_{k-1},x_k)\mapsto (x_1+af(x_k),x_1,x_2,\dots,x_{k-1})$$ where the continuous real-valued function $f$ is one-sided bounded and satisfying the negative feedback condition, $x\cdot f(x)<0, x\ne0$, $a$ is a positive parameter. We show the existence of a compact global attractor for map $F$, and derive a condition for the global attractivity of the zero fixed point.
Mathematics Subject Classification: Primary: 34K20, 34K26; Secondary: 37E05.
Citation:
• [1] P. Collet and J. P. Eckmann, Iterated Maps on the Interval as Dynamical Systems, Birkhäuser, Boston, 1980. [2] W. de Melo and S. van Strien, One-dimensional dynamics, Ergebnisse der Mathematik und ihrer Grenzgebiete 3 [Results in Mathematics and Related Areas 3], 25, Springer-Verlag, Berlin, 1993, 605 pp. [3] R. L. Devaney, An Introduction to Chaotic Dynamical Systems. Second Edition. Addison-Wesley Publ. Co., 1989, 336 pp. [4] O. Diekmann, S. van Gils, S. Verdyn Lunel, and H. O. Walther, Delay Equations: Complex, Functional, and Nonlinear Analysis, Springer-Verlag, New York, 1995. [5] J. K. Hale and S. M. Verduyn Lunel, Introduction to Functional Differential Equations, Springer Applied Mathematical Sciences, 99, 1993. [6] B. Hasselblatt and A. B. Katok, Handbook of dynamical systems, North Holland, 2002. [7] A. F. Ivanov and S. I. Trofimchuk, On global dynamics in a periodic differential equation with deviating argument, Applied Mathematics and Computation, 252 (2015), 446-456. [8] R. D. Nussbaum, Periodic solutions of nonlinear autonomous functional differential equations. Functional differential equations and approximation of fixed points (Proc. Summer School and Conf., Univ. Bonn, Bonn, 1978), pp. 283-325, Lecture Notes in Math., 730, Springer, Berlin, 1979. [9] A. N. Sharkovsky, S. F. Kolyada, A. G. Sivak and V. V. Fedorenko, Dynamics of One-dimensional Maps, Kluwer Academic Publishers, Ser.: Mathematics and Its Application, vol. 407, 1997, 261 pp.
Open Access Under a Creative Commons license
| 2023-03-24T00:50:14 |
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https://mooseframework.inl.gov/source/actions/CommonLineElementAction.html
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## Physics and Syntax
This CommonLineElement action adds the parameters supplied at the [Modules/TensorMechanics/LineElementMaster] level as defaults for all the subblocks within the LineElementMaster block. See the description, example use, and parameters on the LineElementMaster action system page.
| 2019-04-19T06:26:17 |
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https://googology.wikia.org/wiki/Laver_table
|
11,054 Pages
Laver tables are an infinite family of magmas that may give rise to a large number function.[1] They were first defined by Richard Laver in 1992. For $$n \geq 0$$, the size-$$n$$ Laver table is a binary operator $$\star$$ over $$\mathbb{Z}_{2^n}$$, with the following properties:
\begin{eqnarray*} a \star 0 & = & 0 \\ a \star 1 & = & a+1 \\ a \star b & = & (a \star (b-1)) \star (a \star 1) \ (b \neq 0,1) \end{eqnarray*}
The period of the function $$a \mapsto 1 \star a$$ depends on $$n$$, and we will denote it by $$p(n)$$. The first few values of $$p(n)$$ are $$1, 1, 2, 4, 4, 8, 8, 8, 8, 16, 16, 16, 16, \ldots$$ (OEIS A098820), a slow-growing function. $$p$$ is provably divergent in the system ZFC + "there exists a rank-into-rank cardinal." Unfortunately, the latter axiom is so strong that there are a few specialists who doubt the consistency of the system. Since the divergence of $$p$$ has not been proven otherwise, it remains an unsolved problem.
Let $$q(n)$$ be minimal so that $$p(q(n)) \geq 2^n$$, the "pseudoinverse" of $$p$$. $$q$$ is a fast-growing function that is total iff $$p$$ is divergent. The first few values of $$q$$ are $$0, 2, 3, 5, 9$$. The existence of $$q(n)$$ for $$n \geq 5$$ has not even been confirmed, but under the assumption of the previously mentioned axiom, Randall Dougherty has shown that $$q^n(1) > f_{\omega+1}(\lfloor \log_3 n \rfloor - 1)$$ in a slightly modified version of the fast-growing hierarchy,[2] and $$q(5) > f_9(f_8(f_8(254)))$$.[3] Dougherty has expressed pessimism about the complexity of proving better lower bounds, and no upper bounds are known as of yet.
Patrick Dehornoy provides a simple algorithm for filling out Laver tables.[4]
The expected size of $$q(6)$$ was very large[5], however no reasoning or proof has been given other than "the strength of set theories required to prove a computable function total", however a computable function $$f$$ need not outgrows all computable functions provably total in a set theory that is known to be required to prove that the function is total.
## Explanation
For $$\lambda \in \text{Lim}$$, let $$\mathcal{E}_\lambda$$ be the set of elementary embeddings $$V_\lambda \mapsto V_\lambda$$. For $$j,k \in \mathcal{E}_\lambda$$, we define the operator $$j\cdot k$$ (or $$jk$$) as follows:
$j \cdot k = \bigcup_{\alpha < \lambda} j(k \cap V_\alpha)$
Here, $$k \cap V_\alpha$$ is the restriction of $$k$$ to the subset $$\{x \in V_\alpha \mid (x,k(x)) \in V_\alpha\}$$. Although $$k$$ is not an element of the domain $$V_\lambda$$ of $$j$$, $$k \cap V_\alpha$$ is an element of it. That is, we "apply $$j$$ to $$k$$ approaching $$V_\lambda$$." This operator has $$j(kl) = (jk)(jl)$$, a property known as left-selfdistributivity. Laver table is known to be isomorphic to a magma associated to $$\mathcal{E}_\lambda$$ using critical points, and hence is deeply related to a large cardinal axiom.[1]
## Examples
The cyclic group $$\mathbb{Z}_{2^n}$$ can be identified with the set $$\{1,2,3,\ldots,2^n\}$$ through the canonical projection. A size-2 Laver table is shown below:[4]
1 2 3 4
1 2 4 2 4
2 3 4 3 4
3 4 4 4 4
4 1 2 3 4
The entries at the first row repeat with a period of 2, and therefore $$p(2) = 2$$.
A size-3 Laver table is shown below:[4]
1 2 3 4 5 6 7 8
1 2 4 6 8 2 4 6 8
2 3 4 7 8 3 4 7 8
3 4 8 4 8 4 8 4 8
4 5 6 7 8 5 6 7 8
5 6 8 6 8 6 8 6 8
6 7 8 7 8 7 8 7 8
7 8 8 8 8 8 8 8 8
8 1 2 3 4 5 6 7 8
The entries at the first row repeat with a period of 4, and therefore $$p(3) = 4$$.
## Sources
1. Laver, Richard. On the Algebra of Elementary Embeddings of a Rank into Itself. Retrieved 2014-08-23. (Although the last word of the title of the paper is "itself", there is a typo "Inself" in the arXiv page title.)
2. With $$f_{\alpha + 1}(n) = f_\alpha^{n + 1}(1)$$
3. Dougherty, Randall. Critical points in an algebra of elementary embeddings. Retrieved 2014-08-23.
4. Dehornoy, Patrick. Laver Tables (starting on slide 26). Retrieved 2018-12-11.
5. https://googology.wikia.org/wiki/Laver_table?diff=prev&oldid=81250
Community content is available under CC-BY-SA unless otherwise noted.
| 2021-05-10T04:30:08 |
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|
https://www.itl.nist.gov/div898/software/dataplot/refman1/auxillar/cochvari.htm
|
Dataplot Vol 1 Vol 2
# COCHRAN VARIANCE OUTLIER TEST
Name:
COCHRAN VARIANCE OUTLIER TEST
Type:
Analysis Command
Purpose:
Perform Cochran's variance outlier test to assess the homogeneity of variances in the one-factor case.
Description:
Given k groups of data, some analyses assume the standard deviations (or equivalently, variances) are equal for the k groups. For example, the F test used in the one-factor analysis of variance problem can be sensitive to unequal standard deviations in the k levels of the factor.
The Levene and Bartlett tests are widely used for assessing the homogeneity of variances in the one-factor (with k levels) case. The Cochran variance outlier test is another alternative for assessing the homogeneity of variances.
Although the Cochran test has a similar purpose to the Levene and Bartlett tests, it tends to be used in a somewhat different context. The Levene and Bartlett test are used to assess overall homogeneity and are typically used in the context of deciding whether a specific test (e.g., an F test) is appropriate for a given set of data. These tests do not identify which variances are different. On the other hand, the Cochran variance outlier test tends to be used in the context of proficiency testing. In this case, we are primarily interested in identifying laboratories that are "different". For example, a laboratory with an unusually large variance may indicate the need for close examination of that laboratory's practices.
Cochran's test is essentially an outlier test. Cochran's original test statistic is defined as
$$C = \frac{\mbox{largest} s_{i}^{2}} {\sum_{i=1}^{k}{s_{i}^{2}}}$$
That is, it is the ratio of the largest variance to the sum of the variances. This is an upper-tailed test for the maximum variance. The critical values can be computed from
$$C_{UL}(\alpha,n,k) = \frac{1} {1 + \frac{k-1}{FPPF(\alpha/k,(n-1),(k-1) (n-1))}}$$
where
CUL = the upper critical value (i.e., variance is an outlier if the test statistic is greater than CUL) α = the significance level n = the number of observations in each group k = the number of groups FPPF = the percent point function of the F distribution
1. It assumes that the data in each group are normally distributed.
2. It assumes the sample sizes in each group are equal.
3. It tests for the maximum variance only (i.e., no test for the minimum variance).
't Lam (2009) has extended the Cochran test to support unequal sample sizes and tests for the minimum variance. He refers to this as the G statistic. Dataplot in fact generates the G statistic rather than the C statistic for this test. When the sample sizes are in fact equal, the G statistic for the maximum variance is equivalent to the Cochran C statistic.
The G statistic for the j-th group is
$$G_{j} = \frac{\nu_{j} s_{j}^{2}} {\sum_{i=1}^{k}{\nu_{i} s_{i}^{2}}}$$
where νi = ni - 1 with ni denoting the sample size of the i-th group.
The critical value for testing the maximum variance is
$$G_{UL}(\alpha,\nu_{j},\nu_{pool},k) = \frac{1} {1 + \frac{(\nu_{pool}/\nu_{j}) - 1} {FPPF(\alpha/k,\nu_{j},\nu_{pool}-\nu_{j})}}$$
where
$$\nu_{pool}$$ = pooled degrees of freedom = $$\sum_{i=1}^{k}{\nu_{i}}$$ $$\nu_{j}$$ = the degrees of freedom corresponding to the maximum variance
Reject the null hypothesis that the maximum variance is an outlier if the test statistic is greater than the critical value.
The critical value for testing the minimum variance is
$$G_{LL}(\alpha,\nu_{j},\nu_{pool},k) = \frac{1} {1 + \frac{(\nu_{pool}/\nu_{j}) - 1} {FPPF(1 - \alpha/k,\nu_{j},\nu_{pool}-\nu_{j})}}$$
In this case, $$\nu_{j}$$ corresponds to the minimum variance. Reject the null hypothesis that the minimum variance is an outlier if the test statistic is less than the critical value.
A two-sided test can also be performed. Just use α/2 in place of α in the above formulas. Although the 't Lam article provides a method for determining whether the maximum or minimum variance is more extreme, Dataplot will simply return the test statistic and critical values for both the maximum and the minimum cases.
Note that with the G statistic, we are actually testing for the maximum (or minimum) value of the G statistic rather than the maximum (or minimum) variance. If the sample sizes are equal (or at least approximately equal), this should be equivalent. However, if there is a large difference in sample sizes, this may not be the case. That is, we are testing the maximum $$\nu_{j} s_{j}^{2}$$ rather than the maximum $$s_{j}^{2}$$.
If there are potentially multiple outliers in the variances, the recommended procedure is to perform the test sequentially until all outlying variances are removed. That is, if the test indicates the maximum variance is an outlier, remove that group of data and perform the test again. Repeat until the test indicates that
Syntax 1:
COCHRAN VARIANCE OUTLIER TEST <y> <tag>
<SUBSET/EXCEPT/FOR qualification>
where <y> is a response variable;
<tag> is a factor identifier variable;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
This syntax computes the test for the maximum variance.
Syntax 2:
COCHRAN MINIMUM VARIANCE OUTLIER TEST <y> <tag>
<SUBSET/EXCEPT/FOR qualification>
where <y> is a response variable;
<tag> is a factor identifier variable;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
This syntax computes the test for the minimum variance.
Syntax 3:
COCHRAN TWO-SIDED VARIANCE OUTLIER TEST <y> <tag>
<SUBSET/EXCEPT/FOR qualification>
where <y> is a response variable;
<tag> is a factor identifier variable;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
This syntax computes the two-sided test (i.e., both the minimum and maximum variance).
Syntax 4:
MULTIPLE COCHRAN VARIANCE OUTLIER TEST <y1> ... <yk>
<SUBSET/EXCEPT/FOR qualification>
where <y1> ... <yk> is a list of two to 30 response variables;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
This syntax computes the test for the maximum variance.
Syntax 5:
MULTIPLE COCHRAN MINIMUM VARIANCE OUTLIER TEST <y1> ... <yk>
<SUBSET/EXCEPT/FOR qualification>
where <y1> ... <yk> is a list of two to 30 response variables;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
This syntax computes the test for the minimum variance.
Syntax 6:
MULTIPLE COCHRAN TWO-SIDED VARIANCE OUTLIER TEST <y1> ... <yk>
<SUBSET/EXCEPT/FOR qualification>
where <y1> ... <yk> is a list of two to 30 response variables;
and where the <SUBSET/EXCEPT/FOR qualification> is optional.
This syntax computes the two-sided test.
Examples:
COCHRAN VARIANCE OUTLIER TEST Y X
COCHRAN VARIANCE OUTLIER TEST Y X SUBSET X <> 5
COCHRAN MINIMUM VARIANCE OUTLIER TEST Y X
COCHRAN TWO-SIDED VARIANCE OUTLIER TEST Y X
Note:
The following parameters are created automatically by this command
STATVAL = value of test statistic for either the maximum or the minimum case STATCDF = CDF of the test statistic for either the maximum or the minimum case PVALUE = p-value of the test statistic for either the maximum or the minimum case STATVALU = value of test statistic for the maximum variance for the two-sided test STATVALL = value of test statistic for the minimum variance for the two-sided test CUTOF001 = the 0.1% critical value CUTOF005 = the 0.5% critical value CUTOFF01 = the 1% critical value CUTOF025 = the 2.5% critical value CUTOFF05 = the 5% critical value CUTOFF10 = the 10% critical value CUTOFF25 = the 25% critical value CUTOFF50 = the 50% critical value CUTOFF75 = the 75% critical value CUTOFF90 = the 90% critical value CUTOFF95 = the 95% critical value CUTOF975 = the 97.5% critical value CUTOFF99 = the 99% critical value CUTOF995 = the 99.5% critical value CUTOF999 = the 99.9% critical value
P-values are truncated at a minimum of 0.001 and a maximum of 99.999. P-values and CDF statistics are not currently computed for the two-sided case.
Note:
In proficiency testing, John Mandel's k consistency statistic has been used (specifically, the ASTM E-691 standard) to identify laboratories with excessively large variances.
The ISO 5725 standard proposes Cochran's variance outlier test as an alternative to Mandel's k consistency statistic.
Note:
The following statistics are also supported:
LET C = COCHRAN VARIANCE OUTLIER TEST Y X
LET CV95 = COCHRAN VARIANCE OUTLIER CV95 Y X
LET CV99 = COCHRAN VARIANCE OUTLIER CV99 Y X
LET CCDF = COCHRAN VARIANCE OUTLIER CDF Y X
LET CPVAL = COCHRAN VARIANCE OUTLIER PVALUE Y X
LET CM = COCHRAN MINIMUM VARIANCE OUTLIER TEST Y X
LET CMV05 = COCHRAN MINIMUM VARIANCE OUTLIER CV05 Y X
LET CMV01 = COCHRAN MINIMUM VARIANCE OUTLIER CV01 Y X
LET CMCDF = COCHRAN MINIMUM VARIANCE OUTLIER CDF Y X
LET CMPVAL = COCHRAN MINIMUM VARIANCE OUTLIER PVALUE Y X
Enter HELP STATISTICS to see what commands can use these statistics.
Default:
If MIMIMUM or TWO-SIDED is not specified on the command, a test will be performed for the maximum variance.
Synonyms:
COCHRAN VARIANCE OUTLIER is a synonym for COCHRAN VARIANCE OUTLIER TEST
Related Commands:
LEVENE TEST = Compute Levene's test for equal variances. BARTLETT TEST = Compute Bartlett's test for equal variances. F TEST = Performs a two-sample F test for equal variances. VARIANCE PLOT = Plot variances against group-id's.
Reference:
W.G. Cochran (1941), "The distribution of the largest of a set of estimated variances as a fraction of their total," Annals of Human Genetics, (London) 11(1), pp. 47–52.
Ruben U.E. 't Lam (2010), "Scrutiny of Variance Results for Outliers: Cochran's Test Optimized", Analytica Chimica ACTA, Vol. 659, No. 1-2, pp. 68-84.
Kanji (2006), "100 Statistical Tests", SAGE Publications, p. 75.
ISO Standard 5725–2:1994, “Accuracy (trueness and precision) of measurement methods and results – Part 2: Basic method for the determination of repeatability and reproducibility of a standard measurement method”, International Organization for Standardization, Geneva, Switzerland, 1994.
Applications:
Proficiency Tests
Implementation Date:
2015/04
Program:
. Step 1: Read the data
.
dimension 40 columns
skip 25
set write decimals 5
.
. Step 2: Generate a variance plot
.
label case asis
title case asis
title offset 2
xlimits 1 10
major x1tic mark number 10
x1tic mark offset 0.5 0.5
x1label Batch
y1label Variance
line blank solid
character circle blank
character hw 1 0.75
character fill on
title Variance Plot for GEAR.DAT
variance plot y x
.
. Step 2: Perform the test
.
.
cochran variance outlier test y x
let c = cochran variance outlier test y x
let cv95 = cochran variance outlier cv95 y x
let cv99 = cochran variance outlier cv99 y x
let ccdf = cochran variance outlier cdf y x
let cpval = cochran variance outlier pvalue y x
print c cv95 cv99 ccdf cpval
cochran minimum variance outlier test y x
let cm = cochran minimum variance outlier test y x
let cmv05 = cochran minimum variance outlier cv05 y x
let cmv01 = cochran minimum variance outlier cv01 y x
let cmcdf = cochran minimum variance outlier cdf y x
let cmpval = cochran minimum variance outlier pvalue y x
print cm cmv05 cmv01 cmcdf cmpval
cochran two-sided variance outlier test y x
The following output is generated
Cochran Variance Outlier Test
Response Variable: Y
Group-ID Variable: X
H0: Largest Variance is Not an Outlier
Ha: Largest Variance is an Outlier
Summary Statistics:
Total Number of Observations: 100
Number of Groups: 10
Number of Groups with Positive Variance: 10
Group with Largest Variance: 6
Largest Variance: 0.00010
Sum of Variance: 0.00317
Cochran Test Statistic Value: 0.27713
CDF of Test Statistic: 0.98790
P-Value: 0.01210
Percent Points of the Reference Distribution
-----------------------------------
Percent Point Value
-----------------------------------
0.1 = 0.15970
0.5 = 0.15983
1.0 = 0.16000
2.5 = 0.16051
5.0 = 0.16137
10.0 = 0.16315
25.0 = 0.16905
50.0 = 0.18164
75.0 = 0.20180
90.0 = 0.22643
95.0 = 0.24388
97.5 = 0.26050
99.0 = 0.28139
99.5 = 0.29648
99.9 = 0.32953
Conclusions (Upper 1-Tailed Test)
----------------------------------------------
Alpha CDF Critical Value Conclusion
----------------------------------------------
10% 90% 0.22643 Reject H0
5% 95% 0.24388 Reject H0
2.5% 97.5% 0.26050 Reject H0
1% 99% 0.28139 Accept H0
PARAMETERS AND CONSTANTS--
C -- 0.27713
CV95 -- 0.24388
CV99 -- 0.28139
CCDF -- 0.98790
CPVAL -- 0.01210
Cochran Variance Outlier Test
Response Variable: Y
Group-ID Variable: X
H0: Smallest Variance is Not an Outlier
Ha: Smallest Variance is an Outlier
Summary Statistics:
Total Number of Observations: 100
Number of Groups: 10
Number of Groups with Positive Variance: 10
Group with Smallest Variance: 8
Smallest Variance: 0.00001
Sum of Variance: 0.00317
Cochran Test Statistic Value: 0.03730
CDF of Test Statistic: 0.44640
P-Value: 0.44640
Percent Points of the Reference Distribution
-----------------------------------
Percent Point Value
-----------------------------------
0.1 = 0.00779
0.5 = 0.01144
1.0 = 0.01355
2.5 = 0.01702
5.0 = 0.02033
10.0 = 0.02442
25.0 = 0.03147
50.0 = 0.03861
75.0 = 0.04383
90.0 = 0.04650
95.0 = 0.04734
97.5 = 0.04775
99.0 = 0.04800
99.5 = 0.04808
99.9 = 0.04814
Conclusions (Lower 1-Tailed Test)
----------------------------------------------
Alpha CDF Critical Value Conclusion
----------------------------------------------
1% 1% 0.01355 Accept H0
2.5% 2.5% 0.01702 Accept H0
5% 5% 0.02033 Accept H0
10% 10% 0.02442 Accept H0
PARAMETERS AND CONSTANTS--
CM -- 0.03730
CMV05 -- 0.02033
CMV01 -- 0.01355
CMCDF -- 0.44640
CMPVAL -- 0.44640
Cochran Variance Outlier Test
Response Variable: Y
Group-ID Variable: X
H0: Extreme Variance is Not an Outlier
Ha: Extreme Variance is an Outlier
Summary Statistics:
Total Number of Observations: 100
Number of Groups: 10
Number of Groups with Positive Variance: 10
Group with Largest Variance: 6
Largest Variance: 0.00010
Sum of Variance: 0.00317
Cochran Test Statistic Value (upper): 0.27713
Cochran Test Statistic Value (lower): 0.03730
Conclusions (Two-Tailed Test)
-----------------------------------------------------------------------
Significance Lower Upper
Alpha Level Critical Value Critical Value Conclusion
-----------------------------------------------------------------------
10% 90% 0.02033 0.24388 Reject H0
5% 95% 0.01702 0.26050 Reject H0
1% 99% 0.01144 0.29648 Accept H0
NIST is an agency of the U.S. Commerce Department.
Date created: 05/05/2015
Last updated: 01/29/2016
| 2018-04-19T21:24:26 |
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|
https://mooseframework.inl.gov/source/userobject/SolutionUserObject.html
|
# SolutionUserObject
Reads a variable from a mesh in one simulation to another
## Description
A solution user object reads a variable from a mesh in one simulation to another. In order to use a SolutionUserObject three additional parameters are required, an AuxVariable , a Function and an AuxKernel. The AuxVariable represents the variable to be read by the solution user object. The SolutionUserObject is set up to read the old output file. A SolutionFunction is required to interpolate in time and space the data from the SolutionUserObject. Finally, the Function is required that will query the function and write the value into the AuxVariable.
## Example Input Syntax
[UserObjects]
[./soln]
type = SolutionUserObject
mesh = cubesource.e
system_variables = source_nodal
[../]
[]
(test/tests/auxkernels/solution_aux/solution_aux_exodus_interp.i)
## Input Parameters
• meshThe name of the mesh file (must be xda or exodusII file).
C++ Type:MeshFileName
Options:
Description:The name of the mesh file (must be xda or exodusII file).
### Required Parameters
• scale1 1 1 Scale factor for points in the simulation
Default:1 1 1
C++ Type:std::vector
Options:
Description:Scale factor for points in the simulation
• scale_multiplier1 1 1 Scale multiplying factor for points in the simulation
Default:1 1 1
C++ Type:std::vector
Options:
Description:Scale multiplying factor for points in the simulation
• rotation1_vector0 0 1Vector about which to rotate points of the simulation.
Default:0 0 1
C++ Type:libMesh::VectorValue
Options:
Description:Vector about which to rotate points of the simulation.
• rotation1_angle0Anticlockwise rotation angle (in degrees) to use for rotation about rotation1_vector.
Default:0
C++ Type:double
Options:
Description:Anticlockwise rotation angle (in degrees) to use for rotation about rotation1_vector.
• timestepIndex of the single timestep used or "LATEST" for the last timestep (exodusII only). If not supplied, time interpolation will occur.
C++ Type:std::string
Options:
Description:Index of the single timestep used or "LATEST" for the last timestep (exodusII only). If not supplied, time interpolation will occur.
• transformation_ordertranslation scaleThe order to perform the operations in. Define R0 to be the rotation matrix encoded by rotation0_vector and rotation0_angle. Similarly for R1. Denote the scale by s, the scale_multiplier by m, and the translation by t. Then, given a point x in the simulation, if transformation_order = 'rotation0 scale_multiplier translation scale rotation1' then form p = R1*(R0*x*m - t)/s. Then the values provided by the SolutionUserObject at point x in the simulation are the variable values at point p in the mesh.
Default:translation scale
C++ Type:MultiMooseEnum
Options:rotation0 translation scale rotation1 scale_multiplier
Description:The order to perform the operations in. Define R0 to be the rotation matrix encoded by rotation0_vector and rotation0_angle. Similarly for R1. Denote the scale by s, the scale_multiplier by m, and the translation by t. Then, given a point x in the simulation, if transformation_order = 'rotation0 scale_multiplier translation scale rotation1' then form p = R1*(R0*x*m - t)/s. Then the values provided by the SolutionUserObject at point x in the simulation are the variable values at point p in the mesh.
• system_variablesThe name of the nodal and elemental variables from the file you want to use for values
C++ Type:std::vector
Options:
Description:The name of the nodal and elemental variables from the file you want to use for values
• systemnl0The name of the system to pull values out of (xda only).
Default:nl0
C++ Type:std::string
Options:
Description:The name of the system to pull values out of (xda only).
• rotation0_angle0Anticlockwise rotation angle (in degrees) to use for rotation about rotation0_vector.
Default:0
C++ Type:double
Options:
Description:Anticlockwise rotation angle (in degrees) to use for rotation about rotation0_vector.
• execute_onTIMESTEP_ENDThe list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM.
Default:TIMESTEP_END
C++ Type:ExecFlagEnum
Options:NONE INITIAL LINEAR NONLINEAR TIMESTEP_END TIMESTEP_BEGIN FINAL CUSTOM
Description:The list of flag(s) indicating when this object should be executed, the available options include NONE, INITIAL, LINEAR, NONLINEAR, TIMESTEP_END, TIMESTEP_BEGIN, FINAL, CUSTOM.
• translation0 0 0 Translation factors for x,y,z coordinates of the simulation
Default:0 0 0
C++ Type:std::vector
Options:
Description:Translation factors for x,y,z coordinates of the simulation
• rotation0_vector0 0 1Vector about which to rotate points of the simulation.
Default:0 0 1
C++ Type:libMesh::VectorValue
Options:
Description:Vector about which to rotate points of the simulation.
• esThe name of the file holding the equation system info in xda format (xda only).
Default:
C++ Type:FileName
Options:
Description:The name of the file holding the equation system info in xda format (xda only).
### Optional Parameters
• control_tagsAdds user-defined labels for accessing object parameters via control logic.
C++ Type:std::vector
Options:
Description:Adds user-defined labels for accessing object parameters via control logic.
• enableTrueSet the enabled status of the MooseObject.
Default:True
C++ Type:bool
Options:
Description:Set the enabled status of the MooseObject.
• allow_duplicate_execution_on_initialFalseIn the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).
Default:False
C++ Type:bool
Options:
Description:In the case where this UserObject is depended upon by an initial condition, allow it to be executed twice during the initial setup (once before the IC and again after mesh adaptivity (if applicable).
• force_preauxFalseForces the GeneralUserObject to be executed in PREAUX
Default:False
C++ Type:bool
Options:
Description:Forces the GeneralUserObject to be executed in PREAUX
• use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.
Default:False
C++ Type:bool
Options:
Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.
| 2019-04-25T04:45:54 |
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|
https://zbmath.org/authors/?q=ai%3Aranga-rao.r
|
## Ranga Rao, R.
Compute Distance To:
Author ID: ranga-rao.r Published as: Ranga Rao, R.; Rao, R. Ranga External Links: Wikidata · GND · IdRef
Documents Indexed: 24 Publications since 1958, including 4 Books Co-Authors: 6 Co-Authors with 15 Joint Publications 246 Co-Co-Authors
all top 5
### Co-Authors
9 single-authored 6 Parthasarathy, Kalyanapuram Rangachari 5 Varadarajan, Veeravalli S. 4 Bhattacharya, Rabi N. 4 Varadhan, S. R. Srinivasa 1 Bahadur, Raghu Raj 1 Rubel, Lee Albert
all top 5
### Serials
3 Annals of Mathematical Statistics 2 Annals of Mathematics. Second Series 2 Bulletin of the American Mathematical Society 2 Sankhyā 1 Theory of Probability and its Applications 1 Acta Mathematica 1 Fundamenta Mathematicae 1 Illinois Journal of Mathematics 1 Journal of Approximation Theory 1 Journal of Functional Analysis 1 Pacific Journal of Mathematics 1 Transactions of the American Mathematical Society 1 Proceedings of the Indian Academy of Sciences. Mathematical Sciences 1 Classics in Applied Mathematics 1 Wiley Series in Probability and Mathematical Statistics
all top 5
### Fields
7 Topological groups, Lie groups (22-XX) 6 Probability theory and stochastic processes (60-XX) 4 Approximations and expansions (41-XX) 4 Abstract harmonic analysis (43-XX) 3 Harmonic analysis on Euclidean spaces (42-XX) 2 Nonassociative rings and algebras (17-XX) 2 Dynamical systems and ergodic theory (37-XX) 2 Operator theory (47-XX) 2 Global analysis, analysis on manifolds (58-XX) 1 Mathematical logic and foundations (03-XX) 1 Group theory and generalizations (20-XX) 1 Measure and integration (28-XX) 1 Differential geometry (53-XX)
### Citations contained in zbMATH Open
20 Publications have been cited 1,012 times in 1,000 Documents Cited by Year
Normal approximation and asymptotic expansions. Zbl 0331.41023
Bhattacharya, R. N.; Ranga Rao, R.
1976
On deviations of the sample mean. Zbl 0101.12603
Bahadur, R. R.; Ranga Rao, R.
1960
On some explicit formulas in the theory of Weil representation. Zbl 0794.58017
Ranga Rao, R.
1993
Relations between weak and uniform convergence of measures with applications. Zbl 0117.28602
Ranga Rao, R.
1962
Representation of complex semi-simple Lie groups and Lie algebras. Zbl 0177.18004
Parthasarathy, K. R.; Ranga Rao, R.; Varadarajan, V. S.
1967
Normal approximation and asymptotic expansions. (Reprint of the 1976 orig. publ. by Wiley, New York. Repr. ed. with corrections & supplemental material). Zbl 0657.41001
Bhattacharya, R. N.; Ranga Rao, R.
1986
Orbital integrals in reductive groups. Zbl 0302.43002
Ranga Rao, R.
1972
Probability distributions on locally compact Abelian groups. Zbl 0129.10902
Parthasarathy, K. R.; Rao, R. Ranga; Varadhan, S. R. S.
1963
Normal approximation and asymptotic expansions. Updated republication of the 1986 reprint published by Robert E. Krieger Publ. Co. Zbl 1222.41002
Bhattacharya, R. N.; Ranga Rao, R.
2010
The law of large numbers for $$D[0,1]$$-valued random variables. Zbl 0122.13303
Ranga Rao, R.
1963
On the category of indecomposable distributions on topological groups. Zbl 0104.36205
Parthasarathy, K. R.; Ranga Rao, R.; Varadhan, S. R. S.
1962
On the central limit theorem in $$R_k$$. Zbl 0099.13003
Ranga Rao, R.
1961
Unitary representations defined by boundary conditions - the case of sl(2,R). Zbl 0476.43008
Rao, R. Ranga
1978
Normal approximation and asymptotic expansions. (Approksimatsiya normal’nym raspredeleniem i asimptoticheskie razlozheniya). Transl. from the English. Zbl 0514.41002
Bhattacharya, R. N.; Ranga Rao, R.
1982
A limit theorem for densities. Zbl 0101.11603
Ranga Rao, R.; Varadarajan, V. S.
1960
Representations of complex semi-simple Lie groups and Lie algebras. Zbl 0178.16802
Parthasarathy, K. R.; Ranga Rao, R.; Varadarajan, V. S.
1966
A note on finitely additive measures. Zbl 0082.26503
Rao, R. Ranga
1958
On a theorem in metric spaces. Zbl 0088.04104
Varadarajan, V. S.; Ranga Rao, R.
1958
Probability distributions on locally compact abelian groups. Zbl 1316.60025
Parthasarathy, K. R.; Ranga Rao, R.; Varadhan, S. R. S.
2012
Symplectic structures on locally compact abelian groups and polarizations. Zbl 0823.22006
Ranga Rao, R.
1994
Probability distributions on locally compact abelian groups. Zbl 1316.60025
Parthasarathy, K. R.; Ranga Rao, R.; Varadhan, S. R. S.
2012
Normal approximation and asymptotic expansions. Updated republication of the 1986 reprint published by Robert E. Krieger Publ. Co. Zbl 1222.41002
Bhattacharya, R. N.; Ranga Rao, R.
2010
Symplectic structures on locally compact abelian groups and polarizations. Zbl 0823.22006
Ranga Rao, R.
1994
On some explicit formulas in the theory of Weil representation. Zbl 0794.58017
Ranga Rao, R.
1993
Normal approximation and asymptotic expansions. (Reprint of the 1976 orig. publ. by Wiley, New York. Repr. ed. with corrections & supplemental material). Zbl 0657.41001
Bhattacharya, R. N.; Ranga Rao, R.
1986
Normal approximation and asymptotic expansions. (Approksimatsiya normal’nym raspredeleniem i asimptoticheskie razlozheniya). Transl. from the English. Zbl 0514.41002
Bhattacharya, R. N.; Ranga Rao, R.
1982
Unitary representations defined by boundary conditions - the case of sl(2,R). Zbl 0476.43008
Rao, R. Ranga
1978
Normal approximation and asymptotic expansions. Zbl 0331.41023
Bhattacharya, R. N.; Ranga Rao, R.
1976
Orbital integrals in reductive groups. Zbl 0302.43002
Ranga Rao, R.
1972
Representation of complex semi-simple Lie groups and Lie algebras. Zbl 0177.18004
Parthasarathy, K. R.; Ranga Rao, R.; Varadarajan, V. S.
1967
Representations of complex semi-simple Lie groups and Lie algebras. Zbl 0178.16802
Parthasarathy, K. R.; Ranga Rao, R.; Varadarajan, V. S.
1966
Probability distributions on locally compact Abelian groups. Zbl 0129.10902
Parthasarathy, K. R.; Rao, R. Ranga; Varadhan, S. R. S.
1963
The law of large numbers for $$D[0,1]$$-valued random variables. Zbl 0122.13303
Ranga Rao, R.
1963
Relations between weak and uniform convergence of measures with applications. Zbl 0117.28602
Ranga Rao, R.
1962
On the category of indecomposable distributions on topological groups. Zbl 0104.36205
Parthasarathy, K. R.; Ranga Rao, R.; Varadhan, S. R. S.
1962
On the central limit theorem in $$R_k$$. Zbl 0099.13003
Ranga Rao, R.
1961
On deviations of the sample mean. Zbl 0101.12603
Bahadur, R. R.; Ranga Rao, R.
1960
A limit theorem for densities. Zbl 0101.11603
Ranga Rao, R.; Varadarajan, V. S.
1960
A note on finitely additive measures. Zbl 0082.26503
Rao, R. Ranga
1958
On a theorem in metric spaces. Zbl 0088.04104
Varadarajan, V. S.; Ranga Rao, R.
1958
all top 5
### Cited by 1,126 Authors
14 Götze, Friedrich 14 Lahiri, Soumendra Nath 12 Kakizawa, Yoshihide 11 Sunklodas, Jonas Kazys 10 Bobkov, Sergey Germanovich 9 Joseph, Anthony 9 Mandjes, Michel Robertus Hendrikus 8 Chari, Vyjayanthi 8 Dong, Chao-Ping 8 Nadarajah, Saralees 8 Withers, Christopher Stroude 7 Ivanov, Aleksandr Vladimirovich 7 Zeitouni, Ofer 6 Bentkus, Vidmants-Kastytis 6 Bhattacharya, Rabi N. 6 Chistyakov, Gennadiy P. 6 Fel’dman, Gennadiĭ Mikhaĭlovich 6 Greenstein, Jacob 6 Joutard, Cyrille 6 Kaplan, Eyal 6 Kirch, Claudia 6 Korolev, Viktor Yur’evich 6 Sekiya, Yuri 6 Taneichi, Nobuhiro 6 Tortrat, Albert 5 Babu, Gutti Jogesh 5 Bose, Arup 5 Hall, Peter Gavin 5 Heinrich, Lothar 5 Ichino, Atsushi 5 Kabluchko, Zakhar A. 5 Konakov, Valentin 5 Kudla, Stephen S. 5 Lepowsky, James 5 Mammen, Enno 5 Mirakhmedov, Sherzod Mira’zam 5 Przebinda, Tomasz 5 Yang, Tonghai 4 Berkes, István 4 Blasques, Francisco 4 Dudley, Richard Mansfield 4 Gan, Wee Teck 4 Ginzburg, David 4 Grama, Ion G. 4 Hanzer, Marcela 4 Hipp, Christian 4 Jensen, Jens Ledet 4 Jørgensen, Palle E. T. 4 Koopman, Siem Jan 4 Li, Qi 4 Liu, Quansheng 4 Mcvinish, Ross S. 4 Meitz, Mika 4 Paditz, Ludwig 4 Saikkonen, Pentti 4 Shen, Pao-Sheng 4 Soudry, David 4 Szpruch, Dani 4 Tadjuidje-Kamgaing, Joseph 4 Yamana, Shunsuke 4 Zorn, Christian A. 3 Adams, Jeffrey David 3 Barbasch, Dan M. 3 Borovkov, Aleksandr Alekseevich 3 Chatterjee, Shoutir Kishore 3 Cordeiro, Gauss Moutinho 3 Cox, J. Theodore 3 Das, Debraj 3 Dembo, Amir 3 Durrett, Richard Timothy 3 Fan, Xiequan 3 Faÿ, Gilles 3 Fernando, Kasun 3 Flicker, Yuval Z. 3 García-Soidán, Pilar H. 3 Grincevičius, A. K. 3 Helgason, Sigurdur 3 Heyer, Herbert 3 Hounyo, Ulrich 3 Hušková, Marie 3 Iwashita, Toshiya 3 Jing, Bingyi 3 Kostant, Bertram 3 Landers, Dieter 3 Majumdar, Mukul K. 3 Matić, Ivan 3 Meintanis, Simos G. 3 Menozzi, Stéphane 3 Ouimet, Frédéric 3 Paulauskas, Vygantas Ionovič 3 Pène, Françoise 3 Plachky, Detlef 3 Pollett, Philip K. 3 Rao, Calyampudi Radhakrishna 3 Reiss, Rolf-Dieter 3 Riauba, B. A. 3 Richter, Wolf-Dieter 3 Rogge, Lothar 3 Römisch, Werner 3 Rozovskiĭ, Leonid Viktorovich ...and 1,026 more Authors
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### Cited in 231 Serials
41 Journal of Multivariate Analysis 39 Zeitschrift für Wahrscheinlichkeitstheorie und Verwandte Gebiete 32 Journal of Econometrics 32 Statistics & Probability Letters 29 Journal of Statistical Planning and Inference 26 Probability Theory and Related Fields 25 The Annals of Statistics 24 Lithuanian Mathematical Journal 23 Stochastic Processes and their Applications 20 Journal of Algebra 20 Transactions of the American Mathematical Society 19 The Annals of Probability 18 Communications in Statistics. Theory and Methods 16 Annals of the Institute of Statistical Mathematics 16 Journal of Soviet Mathematics 16 Journal of Theoretical Probability 15 Advances in Mathematics 15 Journal of Number Theory 15 The Annals of Applied Probability 13 Inventiones Mathematicae 13 Journal of Mathematical Sciences (New York) 12 Israel Journal of Mathematics 12 Compositio Mathematica 12 Mathematische Zeitschrift 11 Communications in Mathematical Physics 11 Journal of Mathematical Analysis and Applications 11 Manuscripta Mathematica 10 Journal of Functional Analysis 10 Mathematische Nachrichten 10 Statistics 10 Representation Theory 9 Metrika 9 Ukrainian Mathematical Journal 9 Duke Mathematical Journal 9 Bernoulli 7 Journal of Applied Probability 7 Scandinavian Actuarial Journal 7 Journal of Time Series Analysis 6 Journal of Approximation Theory 6 Kybernetika 6 Mathematische Annalen 6 Journal of the American Mathematical Society 5 Theory of Probability and its Applications 5 Proceedings of the American Mathematical Society 5 Siberian Mathematical Journal 5 Advances in Applied Mathematics 5 Journal of Nonparametric Statistics 5 European Series in Applied and Industrial Mathematics (ESAIM): Probability and Statistics 4 Journal of Mathematical Physics 4 Mathematical Notes 4 Scandinavian Journal of Statistics 4 Journal of Economic Theory 4 Test 4 Transformation Groups 4 The Ramanujan Journal 4 Methodology and Computing in Applied Probability 4 Journal of the Institute of Mathematics of Jussieu 4 Electronic Journal of Statistics 4 Science China. Mathematics 3 Communications in Algebra 3 Journal d’Analyse Mathématique 3 Mathematical Proceedings of the Cambridge Philosophical Society 3 Arkiv för Matematik 3 Journal of Geometry and Physics 3 Annales Scientifiques de l’École Normale Supérieure. Quatrième Série 3 Applied Mathematics and Computation 3 Functional Analysis and its Applications 3 Journal of the American Statistical Association 3 Econometric Reviews 3 Geometric and Functional Analysis. GAFA 3 Annales de l’Institut Henri Poincaré. Nouvelle Série. Section B. Calcul des Probabilités et Statistique 3 European Journal of Operational Research 3 Annales de l’Institut Henri Poincaré. Probabilités et Statistiques 3 Computational Statistics and Data Analysis 3 Mathematical Programming. Series A. Series B 3 Electronic Journal of Probability 3 Doklady Mathematics 3 Mathematical Methods of Operations Research 3 Brazilian Journal of Probability and Statistics 3 Stochastic Models 3 Statistical Methodology 3 Bulletin of the American Mathematical Society 3 Sankhyā. Series A 2 Advances in Applied Probability 2 Journal of Mathematical Biology 2 Journal of Statistical Physics 2 Nonlinearity 2 Stochastics 2 Abhandlungen aus dem Mathematischen Seminar der Universität Hamburg 2 Acta Mathematica 2 Annales de l’Institut Fourier 2 Journal of the Mathematical Society of Japan 2 Journal of Optimization Theory and Applications 2 Mathematika 2 Nagoya Mathematical Journal 2 Proceedings of the Japan Academy. Series A 2 Cybernetics 2 Ergodic Theory and Dynamical Systems 2 Insurance Mathematics & Economics 2 Acta Applicandae Mathematicae ...and 131 more Serials
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### Cited in 47 Fields
430 Probability theory and stochastic processes (60-XX) 339 Statistics (62-XX) 162 Topological groups, Lie groups (22-XX) 112 Number theory (11-XX) 55 Nonassociative rings and algebras (17-XX) 34 Numerical analysis (65-XX) 33 Abstract harmonic analysis (43-XX) 32 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 25 Group theory and generalizations (20-XX) 21 Operations research, mathematical programming (90-XX) 19 Statistical mechanics, structure of matter (82-XX) 15 Measure and integration (28-XX) 15 Functional analysis (46-XX) 15 Quantum theory (81-XX) 14 Dynamical systems and ergodic theory (37-XX) 13 Algebraic geometry (14-XX) 12 Differential geometry (53-XX) 12 Biology and other natural sciences (92-XX) 11 Combinatorics (05-XX) 10 Operator theory (47-XX) 8 Linear and multilinear algebra; matrix theory (15-XX) 8 Systems theory; control (93-XX) 8 Information and communication theory, circuits (94-XX) 7 Associative rings and algebras (16-XX) 7 Approximations and expansions (41-XX) 7 Computer science (68-XX) 6 Several complex variables and analytic spaces (32-XX) 6 Partial differential equations (35-XX) 6 Harmonic analysis on Euclidean spaces (42-XX) 6 Convex and discrete geometry (52-XX) 6 General topology (54-XX) 6 Global analysis, analysis on manifolds (58-XX) 5 Functions of a complex variable (30-XX) 5 Special functions (33-XX) 4 Real functions (26-XX) 3 History and biography (01-XX) 3 Calculus of variations and optimal control; optimization (49-XX) 2 Mathematical logic and foundations (03-XX) 2 Ordinary differential equations (34-XX) 2 Difference and functional equations (39-XX) 2 Integral transforms, operational calculus (44-XX) 2 Relativity and gravitational theory (83-XX) 1 Field theory and polynomials (12-XX) 1 Geometry (51-XX) 1 Algebraic topology (55-XX) 1 Manifolds and cell complexes (57-XX) 1 Fluid mechanics (76-XX)
### Wikidata Timeline
The data are displayed as stored in Wikidata under a Creative Commons CC0 License. Updates and corrections should be made in Wikidata.
| 2022-07-01T05:48:09 |
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https://roualdes.us/lecturenotes/sets.html
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# Basic Set Theory
Edward A. Roualdes
Introduction
Sets
Set Operations
## Introduction
Set theory is the starting point for a wide range of topics. At its most basic level, sets just describes groups of things and the theory describes how to logically rearrange sets into new sets. The things are most often numbers, but since we are headed towards an introduction to probability, our sets don't necessarily have to consist of numbers. As such, these notes comprise a collection of material that one should know to understand a short introduction to probability. These notes are not intended to be a comprehensive review of set theory in general.
Two sections follow, Sets and Set Operations. The section Sets describes the basic components of sets and introduces new notation to describe elements of sets. The section Set Operations mostly consists of binary operations on sets. From these binary operations, new sets can be constructed.
## Sets
A set is a collection of things. In mathematics, the things are most often numbers. In the world of probability and statistics, the items in sets are commonly numbers or the outcomes of a process. Sometimes the outcomes of a process are represented as numbers, but it's important to remember that statistics is generally interested in the randomness that generated the outcomes of the process.
The symbol $$\emptyset$$ is known as the empty set. Using curly braces, this set is written as $$\emptyset = \{\}$$. This is the set that consists of no elements. It may seem boring, but it's an important set in mathematical statistics.
Of course, not all sets are empty. The symbol $$\in$$ is used to state that an element is a member of a set. Written $$x \in \mathcal{X}$$, we read $$x$$ is an element of the set $$\mathcal{X}$$. To state that an element is not an element of a set, use the symbol $$\notin$$.
For a non-empty set example, let's move to a set of numbers. We write $$\mathcal{X} = \{1, 2, 3, 4, 5, 6 \}$$, and read this as the set $$\mathcal{X}$$ consists of the integers $$1, 2, 3, 4, 5,$$ and $$6$$. You might imagine a single die roll here, but a set of numbers might represent the outcome of some process.
Imagine random sampling families and counting the number of children each family has. A set of possible number of children in each family could be $$\mathcal{X} = \{1, 2, 3, 4 \}$$. The process here is that of a family having children.
Sets can be very contextualized and yet intangible. For instance, there exists a set of all faculty computers on the Chico State campus. Occassionaly our campus IT tries to make this set more tangible by ensuring that their records appropriately match the hardware in faculty offices. We might write this set as $$\mathcal{X} = \{x_1, x_2, \ldots, x_N \}$$, where $$x_n$$ might be a unique ID associated with each computer.
Sets need not be finite. The interval of all real numbers from $$0$$ to $$1$$ inclusive is infinite, although bounded. We often write this set as $$\mathcal{X} = [0, 1]$$.
In theory sets can be constructed by specifying a set of rules that must hold for an element to be included. Consider the so called set builder notation, to specify the values of $$f(x) = x^2$$ such that the input $$x > \sqrt{5}$$, $$\{ x^2 | x > \sqrt{5} \}$$. The vertical pipe is to be read as such that or given; the set of values of $$x$$ squared, such that $$x$$ is strictly greater than $$\sqrt{5}$$.
## Set Operations
Much like $$+$$ is an operation on two numbers, the following set operations are binary operators where the operands are sets instead of numbers.
To indicate set inclusion, that one set is contained in another set, the symbol $$\subset$$ is used. For instance, $$\{ 1, 2 \}$$ is a subset of $$\{1, 2, 3\}$$. This is written as $$\{ 1, 2 \} \subset \{1, 2, 3\}$$. If the subset has the potential to be equal to the superset, then the symbol $$\subseteq$$ is used. Though, some authors use the symbol $$\subset$$ even when equality is possible. When equality is not possible, the term proper subset is used.
More generally, we might visualize a set hierarchy such as $$A \subset B \subset \mathcal{X}$$ as follows. Imagine that there are elements in the sets, even if they're not drawn.
The next two operations either combine the contents of two sets, or reference only the elements contained in both sets. These two operations are union $$\cup$$ and intersection $$\cap$$, repsectively. Pictures are my preferred strategy for understanding $$\cup$$ and $$\cap$$.
Let $$A, B \subset \mathcal{X}$$. The union of $$A$$ and $$B$$, written $$A \cup B$$, is equal to the set that consists of all elements in either set (counted only once). In set builder notation, $$A \cup B = \{x | x \in A \text{ or } x \in B \}$$. The following display visualizes in blue the set $$\color{#00BFFF}{A \cup B}$$. to addition.
Let $$A, B \subset \mathcal{X}$$. The intersection of $$A$$ and $$B$$, written $$A \cap B$$, is equal to the set that consists of only the elements in both sets. In set builder notation, $$A \cap B = \{x | x \in A \text{ and } x \in B \}$$. The following display visualizes in pink the set $$\color{#00B78D}{A \cap B}$$.
Set difference is the analogue to subtraction. Let $$A \subset B$$. The set difference $$\color{#FF6DAE}{B \setminus A}$$ consists of all the elements of $$B$$ after removing those elements that are also in $$A$$. Think of this as $$B$$ remove $$A$$.
In another analogy to binary operations on numbers, the symbol $$\times$$ when applied to sets is called the Cartesian product. Let $$A, B \subset \mathcal{X}$$. The set $$A \times B = \{(a, b) | a \in A \text{ and } b \in B \}$$, that is the set of ordered pairs that consist of one element from each of the two sets in the product.
Our last set operation is named cardinality. Cardinality measures the number of elements in a set. For the set of suits in a standard deck of cards $$S = \{$$ ♠, , ♣, $$\}$$, the cardinality of $$S$$ is $$|S| = 4$$.
A deck of cards is a set of 52 elements. This set can be thought of as the Cartesian product of the two sets $$S = \{$$ ♠, , ♣, $$\}$$ and $$N = \{ A, 2, 3, 4, 5, 6, 7, 8, 9, 10, J, Q, K \}$$. Since $$|S| = 4$$ and $$|N| = 13$$, the cardinality of a standard deck of cards $$|D| = |S \times N| = 52$$. This is the thinking behind the analogy between the Cartesian product and multiplication.
Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International
| 2020-10-22T10:20:14 |
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https://survivor.togaware.com/gnulinux/freedom.html
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## 1.3 Freedom
Copyright, which comes into existence whenever anything is written, is about the word for word copying of someone else’s words. Copyright protects the original author from others passing the authors work of as their own. On the other hand, a patent provides a monopoly on an idea. If you can describe an idea in words, you can patent it, and thereby prohibit anyone else from using that idea, whether they came up with the idea independently or not.
Richard Stallman likes to analogise with mythical Musical Patents. Beethoven would not have been able to write his symphonies if musical patents existed. “The idea of four note motifs, particular groupings of chords, the idea of having certain instruments playing on their own for a little while, the idea of music getting quieter then returning wth a boom, the crescendo, the string quartet, or the idea of adding a certain instrument to the orchestra could be patented.” Other composers would then be required to pay a royalty to use any of these ideas or else write music that did not infringe these patents. Imagine the task of writing a symphony and attempting to ensure you did not infringe on any music patents. This is the situation software writers face today.
There is much confusion over the terms free software and open source. They are generally not the same thing, and we need to be clear what is meant by free. The issue is not whether one needs to pay for the software, but whether the software has onerous restrictions on what you can do with it. Software that you can download for free may not be free in the sense of free speech. It may be encumbered with restrictions and limitations that inhibit your freedom to make use of that software. Similarly, software that you purchase may in fact place no restrictions or limitations on what you can do with it, and this is indeed then free in the sense of free speech. The issues are most sharply highlighted by the software patents debate of the early 21st Century which puts at risk the free expression of new ideas that build on those that went before.
Open source software is thus not necessarily free software. Indeed, some open source software places considerable restrictions on what you can do with the source code, thus rendering it non-free. GNU software is open source software that is also free in the sense of free speech. This software allows everyone to redistribute and modify the software, without restriction.
We contrast open and free software with proprietary software that we have become familiar with—the software that we buy on trust from a vendor, trust that it will work, trust that it does only what it should do without back doors that allows the vendor or others to break in, and trust that you will be allowed to use the software for your purposes. But the vendor disowns any responsibility if the software fails in any way. When you find it has bugs and is not fit for your purposes you must buy the next version to get something that works for you. You become bound to that vendor and, with proprietary ways of storing your data (as in MSWord), your freedom to choose vendors is very limited. We have become locked in a cycle of secret codes that require us to pay regular dues to some of the riches organisations in the world.
Free and open source software can make development cheaper through sharing of ideas and building on the pool of ideas that become available. Through free software development practises, more people can get involved and work loads can be shared, and people with very different skill levels can collaborate and help increase the overall skill level of the whole community. Bugs are caught quicker because there are more people looking over the source and bugs are fixed quicker because of this. Security flaws will be found sooner, because there are many more eyes looking over the code, and organisations are welcome to themselves review the code they use to become confident in the code.
“Free software demands that the user be granted four kinds of freedom: freedom to run the program, for any purpose; freedom to study how the program works, and adapt it to your own needs; freedom to redistribute copies so you can help your neighbour; and freedom to improve the program, and release your improvements to the public, so that the whole community benefits. A pre-condition for this is the availability of the entire source code, so that along with the freedom comes the responsibility to share your discoveries’’ with others.” From http://www.gnu.org/philosophy/free-sw.html.
Free software projects still need to be structured. Usually they are conducted under the watchful eye of a project leader, commonly referred to as the maintainer. Anyone can contribute to the project and decisions are often discussed openly and decided by consensus after discussion of the technical merits. Sometimes the project leader will need to cast the deciding vote’. Sometimes, the merits of alternative approaches can not be reconciled, and we then have the freedom to branch the software into two alternative, even competing, ideas.
In addition to founding the GNU Project, Richard Stallman founded the Free Software Foundation to pioneer the cause of free software—free software that gives individuals the opportunity to share their innovations and through this to allow others to learn and to contribute their discoveries. The GNU project publishes the philosophy of free software at https://www.gnu.org/philosophy/free-sw.html.
The free software world aims to share their knowledge and software in order for all to gain towards a common goal. The proprietary software world aims to hoard their software, to hide their discoveries, to let others go through the discovery process themselves rather than to innovate from the shoulders of those who went before them.
Stallman characterises the view of the proprietary vendors as: If you share with your neighbour, you are a pirate. If you want any changes, beg us to make them.’’. If I enjoyed a piece of music or a novel, should I be inhibited from lending the CD or the book to my neighbour?
Eric Raymond, in his Musings on Linux and Open Source'' in the bookThe Cathedral and the Bazaar’’ makes compelling arguments for Free and Open Source Software development. Some of his points, paraphrased, are:
• The quality of the software is maintained by a simple strategy of releasing the software to the general public every week and receiving feedback from hundreds of users within days: release early and release often.
• Users can be cultivated into becoming developers if your software is serving a need of theirs. They will add functionality to suit their particular goals, and this functionality is likely to be useful to others.
A review of Richard Stallman’s speech on Software Patents is available from http://www.ariel.com.au/essays/rms-unsw-2004-10-14.html.
In March 2000 Richard Stallman (with Eben Moglen, a professor at Columbia Law School) introduced the GNU Free Documentation License (GFDL). Stallman identifies the GFDL as a means to enlist commercial publishers to fund free document writing without surrendering any vital liberty.
The GFDL identifies the conditions relating to the copying and revision of documents. Documents are more complicated than simply placing source code on the Internet. The GFDL is consequently more complex, covering the mass copying of the document, inclusion in collections, and specific issues relating to the covers.
Two important concepts relating to the availability of the document are introduced: transparent copies of the document and opaque copies of the document. A GFDL document must be transparent—that is, available in a format whose specification is available to the general public and which can be read using free software. Formats such as LaTeX (used for this book) and XML (using publicly available DTDs) are fine. But making your document available only in PostScript or PDF or Microsoft Word is not transparent. These are opaque documents that might suffer the same old problems of document rot—after a few years the documents may no longer be accessible because the proprietor of the proprietary format might have gone out of business and the knowledge of the format has been lost.
The license also identifies invariant sections of a document that must not contain anything that could fall directly within the document’s overall subject, and cannot be modified or removed from the document. In addition, technical measures that obstruct or control the reading and copying of the document can not be used (and hence access to the document can not be restricted).
Your donation will support ongoing availability and give you access to the PDF version of this book. Desktop Survival Guides include Data Science, GNU/Linux, and MLHub. Books available on Amazon include Data Mining with Rattle and Essentials of Data Science. Popular open source software includes rattle, wajig, and mlhub. Hosted by Togaware, a pioneer of free and open source software since 1984. Copyright © 1995-2022 [email protected] Creative Commons Attribution-ShareAlike 4.0
| 2022-07-07T13:07:57 |
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|
https://fallout.fandom.com/wiki/Isolated_cabin
|
## FANDOM
33,887 Pages
The isolated cabin is a location in the Forest region of Appalachia in 2102.
## LayoutEdit
Upon entering the area, the player character will be confronted with several mongrels. The isolated cabin has a small interior living area, with a suitcase on the destroyed bed, a locked safe (Picklock 0) against the left wall and a toolbox on the table. There is a water pump and cooking station just outside the cabin, along with a cooler on the destroyed bench. The cabin has a weapons workbench near the back corner of the cabin in this same area. There are wood piles near the cooking station and additional piles lined up alongside the cabin. There is an outhouse just up the hill containing a first aid kit and a note.
The doghouse contains science equipment such as test tubes and has a periodic table of elements on the inside wall. Two starlight creeper bushes grow outside the cabin.
## AppearancesEdit
The isolated cabin appears only in Fallout 76.
## Behind the scenesEdit
Inside the doghouse near the rusted truck is a mathematical formula written in chalk: $R_{\mu \nu} – \tfrac{1}{2} R g_{\mu \nu} + \Lambda g_{\mu \nu} = \frac{8 \pi G} {c^4} T_{\mu \nu}$. This is an Einstein field equation, first published by Albert Einstein in 1915.
## GalleryEdit
Community content is available under CC-BY-SA unless otherwise noted.
| 2020-04-09T21:35:58 |
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|
https://www.mcs.anl.gov/research/projects/otc/InteriorPoint/abstracts/Luo-Sun.html
|
## An Analytic Center Based Column Generation Algorithm For Convex Quadratic Feasibility Problems
### Z.-Q. Luo and J. Sun
ABSTRACT: We consider the analytic center based column generation algorithm for the problem of finding a feasible point in a set defined by a finite number of convex quadratic inequalities. At each iteration, the algorithm computes an approximate analytic center of the set defined by the intersection of quadratic inequalities generated in the previous iterations. If this approximate analytic center is a solution, then the algorithm terminates; otherwise a quadratic inequality violated at the current center is selected and a new quadratic cut (defined by a convex quadratic inequality) is placed near the approximate center. As the number of cuts increases, the set defined by their intersection shrinks and the algorithm eventually finds a solution of the problem. Previously, similar analytic center based column generation algorithms were studied first for the linear feasibility problem and later for the general convex feasibility problem. Our method differs from these early methods in that we use quadratic cuts" in the computation instead of linear cuts. Moreover, our method has a polynomial worst case complexity of $O(n\ln \frac{1}{\varepsilon})$ on the total number of cuts to be used, where $n$ is the number of convex quadratic inequalities in the problem and $\varepsilon$ is the radius of the largest ball contained in the feasible set. In contrast, the early column generation methods using linear cuts can only solve the convex quadratic feasibility problem in pseudo-polynomial time.
| 2019-09-22T23:16:24 |
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|
https://pos.sissa.it/282/434/
|
Volume 282 - 38th International Conference on High Energy Physics (ICHEP2016) - Higgs Physics
Higgs physics at the Future Circular Collider
D. d’Enterria
Full text: pdf
Pre-published on: February 06, 2017
Published on: April 19, 2017
Abstract
The unique Higgs physics opportunities accessible at the CERN Future Circular Collider (FCC) in electron-positron ($\sqrt{s}$ = 125, 240, 350 GeV) and proton-proton ($\sqrt{s}$ = 100 TeV) collisions, are succinctly summarized. Thanks to the large c.m. energies and enormous luminosities (plus clean experimental conditions in the $e^+e^-$ case), many open fundamental aspects of the Higgs sector of the Standard Model (SM) can be experimentally studied:
Measurement of the Higgs Yukawa couplings to the lightest fermions: u,d,s quarks (via rare exclusive $H\to(\rho,\omega,\phi)+\gamma$ decays); and e$^\pm$ (via resonant s-channel $e^+e^-\to H$ production); as well as neutrinos (within low-scale seesaw mass generation scenarios).
Measurement of the Higgs potential (triple $\lambda_3$, and quartic $\lambda_4$ self-couplings), via double and triple Higgs boson production in pp collisions at 100 TeV.
Searches for new physics coupled to the scalar SM sector at scales $\Lambda>$ 6 TeV, thanks to measurements of the Higgs boson couplings with subpercent uncertainties in $e^+e^-\to H\,Z$.
Searches for dark matter in Higgs-portal interactions, via high-precision measurements of on-shell and off-shell Higgs boson invisible decays.
All these measurements are beyond the reach of pp collisions at the Large Hadron Collider. New higher-energy $e^+e^-$ and pp colliders such as FCC are thus required to complete our understanding of the full set of SM Higgs parameters, as well as to search for new scalar-coupled physics in the multi-TeV regime.
DOI: https://doi.org/10.22323/1.282.0434
How to cite
Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.
Open Access
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
| 2020-12-03T16:14:42 |
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|
https://www.usgs.gov/faqs/are-bats-blind
|
# Are bats blind?
No, bats are not blind. Bats have small eyes with very sensitive vision, which helps them see in conditions we might consider pitch black. They don’t have the sharp and colorful vision humans have, but they don’t need that. Think of bat vision as similar to a dark-adapted Mr. Magoo (a cartoon character with very poor vision).
Learn more at the USGS North American Bat Monitoring Program (NABat) website.
## Related Content
Filter Total Items: 7
### Where do bats live?
Bats can be found in almost all parts of the world and in most regions of the United States. In general, bats seek out a variety of daytime retreats such as caves, rock crevices, old buildings, bridges, mines, and trees. Different species require different roost sites. Some species, such as the Mexican free-tailed and gray bats live in large...
### Why are bats important?
By eating insects, bats save U.S. agriculture billions of dollars per year in pest control. Some studies have estimated that service to be worth over $3.7 billion per year, and possibly as much as$53 billion. This value does not, however, take into account the volume of insects eaten by bats in forest ecosystems and the degree to which that...
### Are bats dangerous?
All healthy bats try to avoid humans by taking flight and are not purposely aggressive. Most bats are about the size of a mouse and use their small teeth and weak jaws to grind up insects. You should avoid handling bats because several species, such as the hoary and big brown bats, have large teeth that can puncture skin if they are handled...
### What do bats eat?
Bats are the most significant predators of night-flying insects. There are at least 40 different kinds of bats in the U.S. that eat nothing but insects. A single little brown bat, which has a body no bigger than an adult human’s thumb, can eat 4 to 8 grams (the weight of about a grape or two) of insects each night. Although this may not sound like...
### Do vampire bats really exist?
Yes, but not in most of the United States. Of the three species of vampire bats in North America, only a single specimen has been recorded for the United States in extreme southwest Texas. Vampire bats do not suck blood--they make a small incision with their sharp front teeth and lap up the blood with their tongue. Vampire bats in Mexico and South...
### How are bats affected by wind turbines?
Dead bats are found beneath wind turbines all over the world. It’s estimated that tens to hundreds of thousands die at wind turbines each year in North America alone. Unfortunately, it’s not yet clear why this is happening. It’s possible that wind turbines interfere with seasonal migration and mating patterns in some species of bats. More than...
### What should I do if I find dead or dying bats, or if I observe bats with signs of White-nose Syndrome?
If you find a dead or dying bat: Contact your state wildlife agency, file an electronic report in those states that offer this service, e-mail U.S. Fish and Wildlife Service biologists in your area, or contact your nearest Fish and Wildlife Service field office to report your potential White-nose Syndrome (WNS) observations. It is important to...
Filter Total Items: 4
Date published: October 23, 2017
### Trick or Treat? The Frightening Threats to Bats
Written by Marisa Lubeck and Ethan Alpern
Date published: August 1, 2017
The cold-loving fungus (Pseudogymnoascus destructans, or Pd) that causes white-nose syndrome, a disease that has killed millions of North American bats during hibernation, could also spread in summer months. Bats and humans visiting contaminated caves and mines can inadvertently contribute to the spread of the fungus, according to a recently published study by the U.S. Geological Survey.
Date published: January 17, 2017
### A Deadly Double Punch: Together, Turbines and Disease Jeopardize Endangered Bats
Date published: March 31, 2011
...
### Endangered Hawaiian Hoary Bat
An endangered Hawaiian hoary bat, a species that is sometimes killed by wind turbines. USGS scientists from Hawaii and Colorado are devising a way to directly observe bat occurrence and behavior at wind turbines using a video system composed of high-powered illuminators and near-infrared cameras. This new approach images the full rotor-swept areas of wind turbines for
...
| 2019-08-21T00:56:26 |
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|
https://par.nsf.gov/biblio/10326086-proprieties-clumps-filaments-around-galaxy-clusters
|
Proprieties of clumps and filaments around galaxy clusters
We report on the possibility of studying the proprieties of cosmic diffuse baryons by studying self-gravitating clumps and filaments connected to galaxy clusters. While filaments are challenging to detect with X-ray observations, the higher density of clumps makes them visible and a viable tracer to study the thermodynamical proprieties of baryons undergoing accretion along cosmic web filaments onto galaxy clusters. We developed new algorithms to identify these structures and applied them to a set of non-radiative cosmological simulations of galaxy clusters at high resolution. We find that in those simulated clusters, the density and temperature of clumps are independent of the mass of the cluster where they reside. We detected a positive correlation between the filament temperature and the host cluster mass. The density and temperature of clumps and filaments also tended to correlate. Both the temperature and density decrease moving outward. We observed that clumps are hotter, more massive, and more luminous if identified closer to the cluster center. Especially in the outermost cluster regions (∼3⋅ R 500, c or beyond), X-ray observations might already have the potential to locate cosmic filaments based on the distribution of clumps and to allow one to study the thermodynamics of diffuse baryons more »
Authors:
; ; ;
Award ID(s):
Publication Date:
NSF-PAR ID:
10326086
Journal Name:
Astronomy & Astrophysics
Volume:
653
Page Range or eLocation-ID:
A171
ISSN:
0004-6361
We study the intrinsic large-scale distribution and evolution of seven ionized metals in the IllustrisTNG magnetohydrodynamical cosmological simulation. We focus on the fractions of C ii, C iv, Mg ii, N v, Ne viii, O vi, and Si iv in different cosmic web structures (filaments, haloes, and voids) and gas phases (warm–hot intergalactic medium, hot, diffuse, and condensed gas) from z = 6 to z = 0. Our analysis provides a new perspective to the study of the distribution and evolution of baryons across cosmic time while offering new hints in the context of the well-known missing baryons problem. The cosmic web components are here identified using the local comoving dark matter density, which provides a simple but effective way of mapping baryons on large scales. Our results show that C ii and Mg ii are mostly located in condensed gas inside haloes in high-density and low-temperature star-forming regions ($\rho _{\rm gas}/\bar{\rho }_{\rm bar}\gtrsim 10^3$, and T ≲ 105 K). C iv and Si iv present similar evolution of their mass fractions in haloes and filaments across cosmic time. In particular, their mass budgets in haloes in condensed phase ($\rho _{\rm gas}/\bar{\rho }_{\rm bar}\gtrsim 10^3$, and T ≲ 105 K) are driven by gas cooling and star formation with a peak at z ∼more »
| 2022-11-26T16:25:12 |
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|
https://control.com/textbook/dc-electricity/inductors/
|
# Introduction to Inductors and Inductance
## Chapter 4 - Basic Direct Current (DC) Theory
Any conductor possesses a characteristic called inductance: the ability to store energy in the form of a magnetic field created by an electric current flowing through that conductor. Inductance is symbolized by the capital letter $$L$$ and is measured in the unit of the Henry (H).
Inductors are devices expressly designed and manufactured to possess inductance. They are typically constructed of a wire coil wound around a ferromagnetic core material. Inductors have current ratings as well as inductance ratings. Due to the effect of magnetic saturation, inductance tends to decrease as current approaches the rated maximum value in an iron-core inductor. Here are some schematic symbols for inductors:
An inductor’s inductance is related to the magnetic permeability of the core material ($$\mu$$), the number of turns in the wire coil ($$N$$), the cross-sectional area of the coil ($$A$$), and the length of the coil ($$l$$):
$L = {\mu N^2 A \over l}$
Inductance is a non-dissipative quantity. Unlike resistance, a pure inductance does not dissipate energy in the form of heat; rather, it stores and releases energy from and to the rest of the circuit. We may illustrate the energy-storing behavior of an ideal inductor by this simple current source, switch, and resistor circuit:
Note how the inductor alternately functions as a source and as a load, depending on what it’s connected to. When connected to a source of current, the inductor absorbs (stores) energy in the form of a magnetic field within its core. Voltage is dropped across the current source in the same polarity as though it were powering a load (e.g. a resistor). When the inductor’s current equals the rated current of the source, there will no longer be a voltage drop (assuming a perfect inductor with zero internal wire resistance). Flipping the switch to the “discharge” position connects the inductor to a resistor, where it discharges its store of energy, acting as a source to the resistor’s load.
Note also how the inductor maintains the same direction of current. Since energy is stored within a magnetic field inside the inductor, and magnetic fields are a function of current, the stored energy manifests itself as a current with an unchanging direction. The Law of Energy Conservation – which states energy cannot spontaneously vanish or appear but must be accounted for – tells us an inductor’s current cannot spontaneously vanish, appear, or change direction. In other words, current is the conserved quantity in an inductor as it transitions between acting as a source and acting as a load. Voltage across an inductor, however, switches polarity depending on whether the inductor is charging (acting as a load) or discharging (acting as a source).
Inductance adds when inductors are connected in series. It diminishes when inductors are connected in parallel:
$L_{series} = L_1 + L_2 + \cdots L_n \hbox{\hskip 50pt} L_{parallel} = {1 \over {1 \over L_1} + {1 \over L_2} + \cdots + {1 \over L_n}}$
Recall that inductance stores energy in the form of a magnetic electric field, as a function of the electric current flowing through it. It we wish to increase inductance by connecting multiple inductors to each other, we need to do that in such a way that each inductor receives the same (total) current so that each additional amount of inductance included in the network will contribute a proportional amount of energy storage to the network. We know current is guaranteed to be equal only among series-connected components. If we were to connect multiple inductors in parallel with one another, their individual currents would be some fraction of the total current (parallel currents always adding to equal the total current), thus diminishing the energy stored in each inductor and similarly diminishing the total inductance.
The relationship between voltage and current for an inductor is as follows:
$V = L{dI \over dt}$
As such, inductors oppose changes in current over time by dropping a voltage. This behavior makes inductors useful for stabilizing current in DC circuits. One way to think of an inductor in a DC circuit is as a temporary current source, always “wanting” to maintain current through its coil as a function of the energy stored within its magnetic field.
The amount of potential energy ($$E_p$$, in units of joules) stored by an inductor may be determined by altering the voltage/current/inductance equation to express power ($$P = IV$$) and then applying some calculus (recall that power is defined as the time-derivative of work or energy, $$P = {dW \over dt} = {dE \over dt}$$):
$V = L{dI \over dt}$
$P = IV = LI{dI \over dt}$
${dE_p \over dt} = LI{dI \over dt}$
${dE_p \over dt} \> dt = LI \> dI$
$\int{dE_p \over dt} \> dt = \int LI \> dI$
$\int dE_p = L \int I \> dI$
$E_p = {1 \over 2}LI^2$
In an AC circuit, the amount of inductive reactance ($$X_L$$) offered by an inductor is directly proportional to both inductance and frequency:
$X_L = 2 \pi f L$
This means an AC signal finds it “harder” to pass through an inductor (i.e. more ohms of reactance) at higher frequencies than at lower frequencies.
Published under the terms and conditions of the Creative Commons Attribution 4.0 International Public License
| 2021-09-22T14:46:52 |
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|
https://www.aimsciences.org/article/doi/10.3934/jmd.2010.4.2i
|
Article Contents
Article Contents
The 2009 Michael Brin Prize in Dynamical Systems (Brin Prize article)
• Professor Michael Brin of the University of Maryland endowed an international prize for outstandingwork in the theory of dynamical systems and related areas. The prize is given biennially for specific mathematical achievements that appear as a single publication or a series thereof in refereed journals, proceedings or monographs.
The prize recognizes mathematicians who have made substantial impact in the field at an early stage of their careers.
The prize is awarded by an international committee of experts chaired by Anatole Katok. Its members are Jean Bourgain, John N. Mather, Yakov Pesin, Marina Ratner, Marcelo Viana and BenjaminWeiss.
Citation:
Open Access Under a Creative Commons license
| 2023-03-27T17:01:46 |
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|
https://pdglive.lbl.gov/DataBlock.action?node=B052M&home=sumtabB
|
# ${{\boldsymbol \Xi}{(1950)}}$ MASS INSPIRE search
VALUE (MeV) EVTS DOCUMENT ID TECN COMMENT
$\bf{ 1950 \pm15}$ OUR ESTIMATE
$1955$ $\pm6$
1999 B
WA89 ${{\mathit \Sigma}^{-}}$ nucleus, 345 GeV
$1944$ $\pm9$ 129
1987
SPEC ${{\mathit \Xi}^{-}}$ ${}^{}\mathrm {Be}$ $\rightarrow$ ( ${{\mathit \Xi}^{-}}{{\mathit \pi}^{+}}$) ${{\mathit \pi}^{-}}$ X
$1963$ $\pm5$ $\pm2$ 63
1987 C
SPEC ${{\mathit \Xi}^{-}}$ ${}^{}\mathrm {Be}$ $\rightarrow$ ( ${{\mathit \Lambda}}{{\overline{\mathit K}}^{0}}$) X
$1937$ $\pm7$ 150
1981
SPEC SPS hyperon beam
$1961$ $\pm18$ 139
1977
HBC 2.87 ${{\mathit K}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \Xi}^{-}}{{\mathit \pi}^{+}}$ X
$1936$ $\pm22$ 44
1977
HBC 2.87 ${{\mathit K}^{-}}$ ${{\mathit p}}$ $\rightarrow$ ${{\mathit \Xi}^{0}}{{\mathit \pi}^{-}}$ X
$1964$ $\pm10$ 56
1977
HBC ${{\mathit \Xi}{(1530)}}{{\mathit \pi}}$
$1900$ $\pm12$
1975
DBC ${{\mathit \Xi}}{{\mathit \pi}}$
$1952$ $\pm11$ 25
1973 C
$1956$ $\pm6$ 29
1972
HBC ${{\mathit \Xi}}{{\mathit \pi}}$ , ${{\mathit \Xi}}{{\mathit \pi}}{{\mathit \pi}}$ , ${{\mathit Y}}{{\mathit K}}$
$1955$ $\pm14$ 21
1970
HBC ${{\mathit \Xi}}{{\mathit \pi}}$
$1894$ $\pm18$ 66
1969
HBC ${{\mathit \Xi}}{{\mathit \pi}}$
$1930$ $\pm20$ 27
1968
HBC ${{\mathit \Xi}^{-}}{{\mathit \pi}^{+}}$
$1933$ $\pm16$ 35
1965
HBC ${{\mathit \Xi}^{-}}{{\mathit \pi}^{+}}$
References:
EPJ C11 271 Production of ${{\mathit \Xi}^{*}}$ Resonances in ${{\mathit \Sigma}^{-}}$ Induced Reactions at 345 ${\mathrm {GeV/}}\mathit c$
BIAGI 1987C
ZPHY C34 175 ${{\mathit \Xi}^{*}}$ Resonances in ${{\mathit \Xi}^{-}}{}^{}\mathrm {Be}$ Interactions. 2. Properties of ${{\mathit \Xi}{(1820)}}$ and ${{\mathit \Xi}{(1950)}}$ in the ${{\mathit \Lambda}}{{\overline{\mathit K}}^{0}}$ and ${{\mathit \Sigma}^{0}}{{\overline{\mathit K}}^{0}}$ Channels
BIAGI 1987
ZPHY C34 15 ${{\mathit \Xi}^{*}}$ Resonances in ${{\mathit \Xi}^{-}}{}^{}\mathrm {Be}$ Interactions. 1. Diffractive Production in the ${{\mathit \Lambda}}{{\mathit K}^{-}}$ and ${{\mathit \Xi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ Channels
BIAGI 1981
ZPHY C9 305 Production of Hyperons and Hyperon Resonances in ${{\mathit \Xi}^{-}}{{\mathit N}}$ Interactions at 102 and 135 ${\mathrm {GeV/}}\mathit c$
BRIEFEL 1977
PR D16 2706 Search for ${{\mathit \Xi}^{*}}$ Production in ${{\mathit K}^{-}}{{\mathit p}}$ Interactions at 2.87 ${\mathrm {GeV/}}\mathit c$
DIBIANCA 1975
NP B98 137 Study of ${{\mathit \Xi}^{-}}$ and ${{\mathit \Omega}^{-}}$ Production from ${{\mathit K}^{-}}{{\mathit n}}$ and ${{\mathit K}^{-}}{{\mathit p}}$ Interactions at 4.93 ${\mathrm {GeV/}}\mathit c$
ROSS 1973C
Purdue Conf. 345 Production of Strangeness -2 Baryons in the Mass Region 1600 to 2100 ${\mathrm {MeV}}/\mathit c$2 in ${{\mathit K}^{-}}{{\mathit p}}$ Interactions at 3.1, 3.3, and 3.6 ${\mathrm {GeV/}}\mathit c$
NP B37 429 Search for ${{\mathit \Xi}^{*}}$ Resonances in ${{\mathit K}^{-}}{{\mathit p}}$ Interactions at 3.95 ${\mathrm {GeV/}}\mathit c$
PR D1 1960 ${{\mathit \Xi}^{-}}$ Production in 5.5 GeV ${{\mathit K}^{-}}{{\mathit p}}$ Interactions
PRL 21 1119 Evidence for ${{\mathit \Xi}}$ Resonance with Mass 1930 MeV
PL 16 171 Baryonic States of Strangeness $-2$ Produced in ${{\mathit K}^{-}}{{\mathit p}}$ Interactions at 3.0 ${\mathrm {GeV/}}\mathit c$
| 2021-01-17T15:16:24 |
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|
https://pdglive.lbl.gov/DataBlock.action?desig=&node=S004EDM&init=0&parCode=S004EDM&cl=T
|
#### ${{\mathit \mu}}$ ELECTRIC DIPOLE MOMENT (d)
A nonzero value is forbidden by both $\mathit T$ invariance and $\mathit P$ invariance.
VALUE ($10^{-19}$ $\mathit e~$cm) CL% DOCUMENT ID TECN CHG COMMENT
$\bf{<1.8}$ 95 1
2009
MUG2 $\pm{}$ Storage ring
• • We do not use the following data for averages, fits, limits, etc. • •
$-0.1$ $\pm1.0$ 2
2009
MUG2 + Storage ring
$-0.1$ $\pm0.7$ 3
2009
MUG2 - Storage ring
$-3.7$ $\pm3.4$ 4
1978
CNTR $\pm{}$ Storage ring
$8.6$ $\pm4.5$
1978
CNTR + Storage ring
$0.8$ $\pm4.3$
1978
CNTR - Storage ring
1 This is the combination of the two BENNETT 2009 measurements quoted here separately for ${{\mathit \mu}^{+}}$ and ${{\mathit \mu}^{-}}$ . The result is also presented as a measurement of ($0.0$ $\pm0.9$) $\times 10^{-19}\mathit e$ cm.
2 Also reported as the limit of $\vert$d(${{\mathit \mu}^{+}}$ )$\vert$ $<$ $2.1 \times 10^{-19}$ $\mathit e$ cm at 95$\%$ CL.
3 Also reported as the limit of $\vert$d(${{\mathit \mu}^{-}}$ )$\vert$ $<$ $1.5 \times 10^{-19}$ $\mathit e$ cm at 95$\%$ CL.
4 This is the combination of the two BAILEY 1978 results quoted here separately for ${{\mathit \mu}^{+}}$ and ${{\mathit \mu}^{-}}$ . BAILEY 1978 uses the convention d = 1/2 $\cdot{}$ (d$_{{{\mathit \mu}^{+}} }−$ d$_{{{\mathit \mu}^{-}} }$) and reports $3.7$ $\pm3.4$. We convert their result to use the same convention as BENNETT 2009 .
Conservation Laws:
TIME REVERSAL ($\mathit T$) INVARIANCE
PARITY ($\mathit P$) INVARIANCE
References:
BENNETT 2009
PR D80 052008 Improved Limit on the Muon Electric Dipole Moment
BAILEY 1978
JP G4 345 New Limits on the Electric Dipole Moment of Positive and Negative Muons
Also
NP B150 1 Final Report on the CERN Muon Storage Ring Including the Anomalous Magnetic Moment and the Electric Dipole Moment of the Muon, and a Direct Test of Relativistic Time Dilation
| 2022-12-07T20:52:21 |
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|
https://issues.cosmos.esa.int/socciwiki/pages/diffpages.action?originalId=77235122&pageId=77235124
|
# Page History
## Key
• This line was removed.
• Formatting was changed.
...
• Raw and Partially Processed products: Version 2
• FREND Dosimeter Calibrated products: Version 1 to be released in 2021
• FREND Neutron Detector Calibrated products: not yet available Version 1 to be released in 2021
Note that the PSA stores all versions, so it's possible to retrieve e.g. version 1 of the raw products. It is advisable however to always use the latest version available.
...
See the EAICD for more details.
# Current Issues
Ref.Issue
Affects
Version
Status
C2Labels bundle_em16_tgo_frd.xml and collection_data_*.xml have several issues (e.g. incorrect information_model_version, incomplete declarations of dictionaries even though not used, Citation_Information incomplete etc). This is because the bundle is dynamically generated at the PSA level and the tool implemented for this task needs to be rectified. This issue is currently under investigation with the PSA team.1.x, 2.xIn analysis
C3PDS is changing its LID convention for instruments. This will require a change from
• urn:esa:psa:context:instrument:frend.tgo
to
• urn:esa:psa:context:instrument:tgo.frend
Coordination is required to make this update as it has an impact on ingestion and the PSA database. Coordination between all missions and instruments is required.
1.x, 2.xIn analysis
C4The lid for the EAICD is incorrect and needs to be rectified with the lid contained in the products1.xIn analysis
C5ExoMars namespace and instrument contexts are not yet registered in the PDS system, therefore the validator by default will not work. Workarounds for the moment are adding the missing items in file validate-1.23.1/resources/registered_context_products.json or running the validator skipping the check on context (--skip-context-validation)--
C6The lids of calibrated products are currently under revision and will be changed to respect the format
<instrument_acronym>_[<processing_level>]_[<type>]_[<subunit>]_<descriptor>
1.xIn analysis
C7NASA validator tool (https://nasa-pds.github.io/validate/) resolves the https PSA protocols with the latest Java version. If validate does not resolve the dictionaries, please consider updating your Java version--
# Fixed Issues
Ref.Issue
Affects
Version
When FixedData Processing Fix VersionPSA Fix Version
O1The current context lid_reference
• urn:nasa:pds:context:target:calibration.non_science
has been deprecated by PDS. The new context/LID will be:
• urn:nasa:pds:context:target:calibrator.non_science
1.x, 2.x2020-04-06DPS-3.8Not Applicable
O2For older Raw products, the URLs pointing to PDS and PSA dictionaries are http instead of https. This has been corrected recently and newer products reflect the change. Older products will be aligned in the next bulk reprocessing. Note that for FREND calibrated products the URL for the PDS schematron still points to http instead of https. This will be corrected for future deliveries. 1.x, 2.x2020-01-30DPS-3.4Not Applicable
O3In the UI, for some products, the fields Wavelength Range and Instrument Type show the incorrect value of "Not Available". 2.xMay 2020Not ApplicablePSA 5.9
O4Currently there are multiple problems associated with the 'on the fly' generated collection and bundle inventory files. The issues are understood, how to implement to the fix is in analysis.1.x, 2.x2020-10-19Not ApplicablePSA 5.10
...
| 2022-01-26T05:30:41 |
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|
https://tjyj.stats.gov.cn/CN/Y2012/V29/I4/44
|
• 论文 •
### 我国通货膨胀决定因素的计量分析
• 出版日期:2012-04-15 发布日期:2012-04-17
### An Econometric Analysis of the Determinants of Inflation in China
Wang Jinming
• Online:2012-04-15 Published:2012-04-17
Abstract: This paper analyses the effects of aggregate demand factors, monetary factors and production cost factors on China’s inflation. We calculate the dynamic Philips curve and argue that the effect of the output gap on price tends to decline, implying that the pulling effect of the aggregate demand decreases. This paper selects monetary factors and purchasing price of goods and, by the NBER method, calculates the composite index. Then, we introduce them, together with the indicator reflecting wage cost, into the expanded Philips curve and the results show that the pushing effects of the monetary factors and production costs are significant. Thus, this paper argues that, under today’s circumstance of tight monetary policy in China, the determined reasons of the current high inflation are the rises of purchasing price of goods especially the wage cost.
| 2022-07-05T03:13:17 |
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|
https://gea.esac.esa.int/archive/documentation/GDR3/Data_analysis/chap_cu3qso/sec_cu3qso_char/ssec_cu3qso_char_attributes.html
|
12.3.3 Source attribute distribution
$G$ magnitude
Figure 12.7 and Figure 12.9 show the magnitude distribution of the sources from each of the modules contributing to the respective extragalactic tables.
The magnitude distribution of sources in the qso_candidates table shows two main components. First, all modules but DSC and QSOC have their sources at magnitude fainter than 12.8 mag, and follow the typically log-like increase with magnitude, dropping after $\sim$20–21 mag. The DSC-Joint sample does not contain any source brighter than magnitude 14.5 because of a specific threshold applied in one of the classifier used to define this class (‘Allosmod’). Then, the DSC and QSOC sources distribution in the magnitude range 13–21 is similar to those of the other modules, augmented by a population of brighter sources all the way from $\sim$15 mag down to $\sim$2 mag, as well as a fainter population extending up to $\sim$22.5 mag. Both extra populations are most likely composed of stars, and are simply a consequence of the lack of hard cuts and filters compared to other classifiers, which results in a more complete but less pure sample. As explained in Section 12.2.1, a purer subset of the DSC sample is available through the DSC-Joint class.
At the bright end, it is possible to check how many of the sources have a counterpart on the Gaia DR3 cross-match tables created against catalogues such as Hipparcos-2 or Tycho-2 TDSC (Chapter 15). This is illustrated in Figure 12.8. Most sources brighter than $\sim$11 mag can be matched to one source in Tycho-2, while all sources brighter than $\sim$7 mag can be matched to one source in Hipparcos, the bulk of which being reported as double by this catalogue or happen to only have a 2-parameter solution in Gaia DR3.
For sources in the galaxy_candidates table, a similar distinction exists between sources from DSC, and those from the other modules. For the latter, the magnitudes range from $\sim$16 mag to $\sim$22 mag and follow a typical log-like increase with magnitude, albeit with noticeably different magnitude coverage between modules. DSC-Joint corresponds to the ‘brightest’ range (15.6 to 21.3 mag), followed by the Vari-Classification (17.6 to 22.3 mag) and finally the Surface brightness sample (19 to 21.6 mag). For UGC, the straight cuts at 17 and 21 mag respectively are due to the training set used for the redshift determination (Delchambre et al. 2022). Complementary to this, and similar to the qso_candidates table, the completeness-driven DSC sample spans magnitude ranging from 22.7 mag, all the way down to 2.1 mag, and adds a significant fraction of sources at all magnitudes.
$G_{\mathrm{BP}}-G_{\mathrm{RP}}$ colour
Figure 12.10 and Figure 12.11 illustrate the distribution of the $G_{\mathrm{BP}}-G_{\mathrm{RP}}$ colours for the same samples.
In the qso_candidates table, the DSC and QSOC samples span the largest colour range, indicative of the colour spread applicable to the significant stellar content of these subsets. Samples expected to be purer in terms of extragalactic content such as DSC-Joint, the Gaia-CRF3 or the Vari-Classification sample, show noticeably narrower and bluer colour distributions. Overall, all distributions peak around $G_{\mathrm{BP}}-G_{\mathrm{RP}}$ $=$ 0.5. A similar behaviour is observed in the galaxy_candidates table in all respects, this time with a distribution peaking around $G_{\mathrm{BP}}-G_{\mathrm{RP}}$ $=$ 1.5.
Re-calibrated flux excess factor
It is also interesting to consider the re-calibrated flux excess factor as introduced by Riello et al. (2021) as a measure of possible source extent, and check its behaviour depending on various attributes. In order to avoid any magnitude dependency of the uncertainty of this excess ratio, we use here its value normalised by its error, which we call $C^{*}/C^{*}_{error}$, and plot it against the $G_{\mathrm{BP}}-G_{\mathrm{RP}}$ colour. Values of this ratio deviating noticeably from 0 are indicative of flux contamination from another object near the source, or of measurable source extent.
Figure 12.12 shows the distribution of the normalised flux excess factor against the $G_{\mathrm{BP}}-G_{\mathrm{RP}}$ colour for all sources in the qso_candidates table. The bulk of the sources exhibit small ratios distributed over the full colour range, but some vertical chimneys appear at certain colours. The left panel shows that the smallest of those chimneys at $G_{\mathrm{BP}}-G_{\mathrm{RP}}$ $\sim$ 1.5 coincides essentially with sources from the Gaia-CRF3, with a fraction of them reported as having a host galaxy detected by the surface brightness analysis. The right panel shows that the faintest sources are those with the smallest ratio, while the two largest chimneys tend to be composed of brighter sources. In particular, the one centred at $G_{\mathrm{BP}}-G_{\mathrm{RP}}$ $\sim$ 0.5 contains essentially all sources brighter than 13 mag (those brighter than 5 even exhibit negative value of the normalised excess factor), of which the majority are likely to be stellar.
It is then interesting to further separate these sources following their DSC class probability. This is shown in Figure 12.13. The two largest chimney tend to have high probability to be a quasar, and a low probability to be a galaxy – in practice, a large fraction of those are believed to be genuine stars. Conversely, the small chimney containing the Gaia-CRF3 sources appears with high probabilities for the galaxy class.
The picture emerging from these plots is as follows:
• The sources coinciding with the Gaia-CRF3 and detected host galaxies are interpreted as extended extragalactic sources, that DSC has classified as galaxy.
• The sources coinciding with the largest chimneys are interpreted as stellar contamination made of stellar pairs, and/or stemming from dense area where the flux excess factor is higher. We propose that the brightest ones (bluest chimney at $G_{\mathrm{BP}}-G_{\mathrm{RP}}$ $\sim$ 0.5) correspond rather to binaries. This particularly applies to the brightest stars where the cross-match with Hipparcos (see above) confirms that many of them belong to double systems. On the other hand, the chimney hosting the faintest objects is mostly tracing dense areas, and it can be checked that they actually all lie at galactic latitudes below 10 degrees.
| 2023-03-29T07:16:21 |
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|
https://www.ctcms.nist.gov/potentials/atomman/
|
atomman: Atomistic Manipulation Toolkit
Description
atomman is a Python library for creating, representing, manipulating, and analyzing large-scale atomic systems of atoms. The focus of the package is to facilitate the rapid design and development of simulations that are fully documented and easily adaptable to new potentials, configurations, etc. The code has no requirements that limit which systems it can be used on, i.e. it should work on Linux, Mac and Windows computers.
Features:
1. Allows for efficient and fast calculations on millions of atoms, each with many freely defined per-atom properties.
2. Create dislocation monopoles and evaluate them with differential displacement and Nye tensor plots.
3. Generate point defects.
4. Call LAMMPS directly from Python and instantly retrieve the resulting data or LAMMPS error statement.
5. Easily convert systems to/from the other Python atomic environments of ASE and PyMatGen.
6. Can create systems based on CIF crystal structure files, and LAMMPS atom and dump files.
7. Built-in unit conversions.
Installation
As of version 1.2, the atomman package is Python 2/3 compatible. It makes heavy use of numpy, so it’s easiest to download a Python environment like Anaconda.
The latest release can be installed using pip:
pip install atomman
This pip command should install atomman and any other required packages, but occasionally a requirement may have to be installed separately. The list of required packages are given below.
| 2018-10-16T14:48:52 |
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|
https://pdglive.lbl.gov/Particle.action?node=M015
|
LIGHT UNFLAVORED MESONS($\mathit S$ = $\mathit C$ = $\mathit B$ = 0) For $\mathit I = 1$ (${{\mathit \pi}}$, ${{\mathit b}}$, ${{\mathit \rho}}$, ${{\mathit a}}$): ${\mathit {\mathit u}}$ ${\mathit {\overline{\mathit d}}}$, ( ${\mathit {\mathit u}}$ ${\mathit {\overline{\mathit u}}}−$ ${\mathit {\mathit d}}$ ${\mathit {\overline{\mathit d}}})/\sqrt {2 }$, ${\mathit {\mathit d}}$ ${\mathit {\overline{\mathit u}}}$;for $\mathit I = 0$ (${{\mathit \eta}}$, ${{\mathit \eta}^{\,'}}$, ${{\mathit h}}$, ${{\mathit h}^{\,'}}$, ${{\mathit \omega}}$, ${{\mathit \phi}}$, ${{\mathit f}}$, ${{\mathit f}^{\,'}}$): ${\mathit {\mathit c}}_{{\mathrm {1}}}$( ${{\mathit u}}{{\overline{\mathit u}}}$ $+$ ${{\mathit d}}{{\overline{\mathit d}}}$ ) $+$ ${\mathit {\mathit c}}_{{\mathrm {2}}}$( ${{\mathit s}}{{\overline{\mathit s}}}$ ) INSPIRE search
#### ${{\boldsymbol \rho}_{{3}}{(1690)}}$
$I^G(J^{PC})$ = $1^+(3^{- -})$
${{\boldsymbol \rho}_{{3}}{(1690)}}$ MASS
Mass $\mathit m$ $1688.8 \pm2.1$ MeV
2 ${{\mathit \pi}}$ MODE $1686 \pm4$ MeV
${{\mathit K}}{{\overline{\mathit K}}}$ AND ${{\mathit K}}{{\overline{\mathit K}}}{{\mathit \pi}}$ MODES $1696 \pm4$ MeV
(4${{\mathit \pi}}){}^{+-}$ MODE $1686 \pm5$ MeV (S = 1.1)
${{\mathit \omega}}{{\mathit \pi}}$ MODE $1681 \pm7$ MeV
${{\mathit \eta}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ MODE $1682 \pm12$ MeV
${{\boldsymbol \rho}_{{3}}{(1690)}}$ WIDTH
2 ${{\mathit \pi}}$ , ${{\mathit K}}{{\overline{\mathit K}}}$ , AND ${{\mathit K}}{{\overline{\mathit K}}}{{\mathit \pi}}$ MODES $161 \pm10$ MeV (S = 1.5)
2${{\mathit \pi}}$ MODE $186 \pm14$ MeV (S = 1.3)
${{\mathit K}}{{\overline{\mathit K}}}$ AND ${{\mathit K}}{{\overline{\mathit K}}}{{\mathit \pi}}$ MODES $204 \pm18$ MeV
(4${{\mathit \pi}}){}^{+-}$ MODE $129 \pm10$ MeV
${{\mathit \omega}}{{\mathit \pi}}$ MODE $190 \pm40$ MeV
${{\mathit \eta}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ MODE $126 \pm40$ MeV (S = 1.8)
$\Gamma_{1}$ 4 ${{\mathit \pi}}$ $(71.1\pm{1.9})\%$ 790
$\Gamma_{2}$ ${{\mathit \pi}^{\pm}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ $(67\pm{22})\%$ 787
$\Gamma_{3}$ ${{\mathit \omega}}{{\mathit \pi}}$ $(16\pm{6})\%$ 655
$\Gamma_{4}$ ${{\mathit \pi}}{{\mathit \pi}}$ $(23.6\pm{1.3})\%$ 834
$\Gamma_{5}$ ${{\mathit K}}{{\overline{\mathit K}}}{{\mathit \pi}}$ $(3.8\pm{1.2})\%$ 629
$\Gamma_{6}$ ${{\mathit K}}{{\overline{\mathit K}}}$ $(1.58\pm{0.26})\%$ S=1.2 685
$\Gamma_{7}$ ${{\mathit \eta}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ seen 727
$\Gamma_{8}$ ${{\mathit \rho}{(770)}}{{\mathit \eta}}$ seen 520
$\Gamma_{9}$ ${{\mathit \pi}}{{\mathit \pi}}{{\mathit \rho}}$ seen 633
$\Gamma_{10}$ ${{\mathit a}_{{2}}{(1320)}}{{\mathit \pi}}$ seen 307
$\Gamma_{11}$ ${{\mathit \rho}}{{\mathit \rho}}$ seen 335
$\Gamma_{12}$ ${{\mathit \phi}}{{\mathit \pi}}$ 525
$\Gamma_{13}$ ${{\mathit \eta}}{{\mathit \pi}}$ 749
$\Gamma_{14}$ ${{\mathit \pi}^{\pm}}$2 ${{\mathit \pi}^{+}}$2 ${{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ 694
FOOTNOTES
| 2021-09-20T03:13:27 |
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https://par.nsf.gov/biblio/10317812-low-energy-elastic-electron-scattering-from-helium-atoms
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This content will become publicly available on December 1, 2022
Low-Energy Elastic Electron Scattering from Helium Atoms
We reinvestigate a key process in electron-atom collision physics, the elastic scattering of electrons from helium atoms. Specifically, results from a special-purpose relativistic polarized-orbital method, which is designed to treat elastic scattering only, are compared with those from a very extensive, fully ab initio, general-purpose B-spline R-matrix (close-coupling) code.
Authors:
; ;
Award ID(s):
Publication Date:
NSF-PAR ID:
10317812
Journal Name:
Atoms
Volume:
9
Issue:
4
ISSN:
2218-2004
3. Abstract We detail the sensitivity of the proposed liquid xenon DARWIN observatory to solar neutrinos via elastic electron scattering. We find that DARWIN will have the potential to measure the fluxes of five solar neutrino components: pp , $$^7$$ 7 Be, $$^{13}$$ 13 N, $$^{15}$$ 15 O and pep . The precision of the $$^{13}$$ 13 N, $$^{15}$$ 15 O and pep components is hindered by the double-beta decay of $$^{136}$$ 136 Xe and, thus, would benefit from a depleted target. A high-statistics observation of pp neutrinos would allow us to infer the values of the electroweak mixing angle, \sinmore »
| 2022-08-12T23:41:55 |
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http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S2007-09342018000501007&lng=pt&nrm=iso&tlng=en
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## Artigo
• Similares em SciELO
## versão impressa ISSN 2007-0934
### Rev. Mex. Cienc. Agríc vol.9 no.5 Texcoco Jun./Ago. 2018
#### https://doi.org/10.29312/remexca.v9i5.716
Articles
Analysis of competitiveness and profitability of biodiesel production from moringa grains in Chiapas and Yucatán, Mexico
1Experimental field Central Valley of Oaxaca-INIFAP. Melchor Ocampo Street num. 7, Santo Domingo Barrio Bajo, Etla, Oaxaca, Mexico. CP. 68200.
2Mococha Experimental Field-INIFAP. Old highway Mérida-Motúl km 25, Yucatán, México. ([email protected]).
3Rosario Izapa Experimental Field-INIFAP. Highway Tapachula-Cacahoatán km 18, Tuxtla Chico, Chiapas, Mexico. CP. 30700, ([email protected]).
Abstract
The production of biofuels worldwide has grown exponentially in recent years, its development has been linked to the increase in the price of oil and the growing social awareness developed around the care of the environment. The world is currently betting on biodiesel as a partial alternative to fossil fuels given that it comes from renewable sources and significantly reduces carbon dioxide emissions into the atmosphere. Technological advances broaden the range of raw materials for biofuels, some of which; how fast-growing grasses and trees can grow in less fertile and drought-prone regions and compete less with crops for the production of human and animal food such as corn, sugar cane, soybeans and rapeseed, such this is the case of Moringa oleifera, which is currently cultivated in practically all the tropical, subtropical and semi-arid regions of the world, since it can grow under conditions of water scarcity. The objective of this research was to economically evaluate the integral production of biodiesel with moringa grains considering two agroecological zones of raw material production, the Soconusco, Chiapas and Uxmal, Yucatan and their transformation to biodiesel through the process of industrial transesterification in a pilot plant. For the agricultural and industrial phases, profitability indicators were generated such as the internal rate of return (TIR), net present value (VAN) and equilibrium point (PE). The results indicated that the agricultural production is highly profitable due to the additional use of the leaves as co-product with TIR of 109 and 130% for the Soconusco, Chiapas and Uxmal, Yucatán, respectively, while the industrial phase, considering zero subsidies to the production of biodiesel was profitable with TIR of 53% in Uxmal, Yucatan and 37% in Soconusco, Chiapas.
Keywords: Moringa oleifera; biodiesel; competitiveness; profitability of biofuels
Resumen
La producción de biocombustibles a nivel mundial ha crecido exponencialmente en los últimos años, su desarrollo ha estado ligado al aumento del precio del petróleo y a la creciente concientización social desarrollada en torno al cuidado del medio ambiente. El mundo apuesta actualmente por el biodiesel como alternativa parcial a los combustibles de origen fósil dado que procede de fuentes renovables y permite reducir, de modo significativo, las emisiones de dióxido de carbono a la atmósfera. Los avances tecnológicos amplían la gama de materias primas para biocombustibles, algunas de las cuales; como los pastos y los árboles de crecimiento rápido pueden crecer en regiones menos fértiles y más propensas a la sequía y compiten menos con cultivos para la producción de alimentos humano y animal como el maíz, la caña de azúcar, la soya y la colza, tal es el caso de Moringa oleifera que en la actualidad se cultiva prácticamente en todas las regiones tropicales, subtropicales y semiáridas del mundo, ya que puede crecer en condiciones de escasez de agua. El objetivo de esta investigación fue evaluar económicamente la producción integral de biodiesel con granos de moringa considerando dos zonas agroecológicas de producción de materia prima, el Soconusco, Chiapas y Uxmal, Yucatán y su transformación a biodiesel mediante el proceso de transesterificación industrial en una planta piloto. Para las fases agrícola e industrial, se generaron los indicadores de rentabilidad como la tasa interna de retorno (TIR), valor actual neto (VAN) y punto de equilibrio (PE). Los resultados indicaron que la producción agrícola es altamente rentable debido al aprovechamiento adicional de las hojas como coproducto con TIR de 109 y 130% para el Soconusco, Chiapas y Uxmal, Yucatán, respectivamente, mientras que la fase industrial, considerando cero subsidios a la producción de biodiesel resultó rentable con TIR de 53% en Uxmal, Yucatán y 37% en el Soconusco, Chiapas.
Introduction
Climate change whose main characteristic is the increase in the temperature of the earth, is one of the current problems facing humanity, because its effects affect the economic, social and environmental, putting at risk the very survival of the humanity; this change in temperature patterns is mainly caused by the excessive emission of carbon dioxide and its accumulation in the atmosphere (Pardo, 2007; Gómez, 2007), which causes other meteorological phenomena such as droughts, melting of the poles and flooding between others; these phenomena affect the daily lives of people, family and national economies as well as agricultural and forestry production and productivity. It was estimated that in 2005 the economic losses from global warming exceeded 200 billion dollars (Zamarripa et al., 2009).
Faced with this problem, several countries are promoting the use of more efficient and cleaner renewable energies such as biofuels to reduce the effects of global warming and contribute to the conservation of the environment. In addition, in the particular case of Mexico, the depletion of proven oil reserves, estimated to last for 8 years, highly justify the exploration of new renewable energy sources such as bioethanol and biodiesel from agricultural species (Rico et al., 2011).
At present, there are advances in several countries where the production of biofuels translates into benefits for farmers, since on the one hand it becomes a sustainable source of energy and on the other it is seen as a new source of income and work for farmers and rural communities around the world (Muñoz, 2013). Contrary to oil and coal, which are unevenly distributed across countries, all nations could generate a certain amount of bioenergy from some type of internally produced biomass and, thereby, help reduce their dependence on fossil fuels imported (Hazell and Pachauri, 2006).
In Mexico from the legal point of view, bioenergy was not a matter of regulation until the beginning of 2008 when the Law of Promotion and Development of Bioenergetics was published in the Official Gazette of the Federation, issuing the guidelines for the granting of permits for the production, storage, transportation and commercialization of bioenergetics of the anhydrous ethanol and biodiesel type (Sepúlveda, 2012), taking an essential step to promote its introduction as a complement to the supply of vehicular fuels, where it is perceived that they offer environmental benefits the lower emission of pollutants and at the same time it is expected that the ejidatarios, comuneros and the workers of the field in general, improve their economy by being able to participate with private investors for the cultivation of species that provide raw material for the production of biodiesel and bioethanol (Gamboa, 2009).
Despite the obvious possibilities that bioenergy presents for economic and social development, there are still important questions about what this implies for rural communities, the environment and international trade, indeed, because most of the benefits and environmental and social costs of bioenergy are not subject to a sufficiently developed market, it is necessary to define public policies in order to maximize these potentialities (Islas and Martínez, 2009). The public sector has an important role to play in ensuring positive outcomes, such as the development and implementation of appropriate policies, the development of appropriate technologies and the creation of favorable investment environments that are needed to ensure that bioenergy is developed efficiently, whose results are compatible with the reduction of poverty and global warming (Hazell and Pachauri, 2006).
Various raw materials such as sugar cane, soybeans and corn have been used for the production of biofuels, however, there is disagreement in their cultivation for that purpose, since they compete for their use in the production of human and animal food and this has caused that the sowing surface destined to the production of oleaginous and grain is insufficient (Collymore et al., 2008; Huerta, 2010; Ramos, 2010). For this reason, technologies have been developed that not only help bioenergy compete better with fossil fuels in terms of price, but also the range of raw material options, such as fast-growing grasses and trees, has been expanded. they can thrive in regions that are not very fertile and prone to drought (Hazell and Pachauri, 2006). Such is the case of Moringa oleifera, which represents a technical, socioeconomic and environmentally favorable opportunity for its use in the production of biodiesel and other beneficial coproducts for society.
Moringa is a tree native to India, where its fruits, seeds and roots are mainly used for human consumption, while its stems are used for animal feed; in addition, the oil extracted from its seeds is used as a lubricant and in the cosmetic industry for the manufacture of creams and soaps (Martín et al., 2013). It is a perennial species tolerant to high temperatures and drought, its optimal temperature range is between 15 to 35 degrees Celcius (Pérez, 2010). In general, it thrives best with annual rainfall of 500 to 1 500 mm (Pérez, 2010), it grows very little when it is cultivated at altitudes higher than 1 500 meters above sea level, so its cultivation is recommended below 500 meters above sea level (Olson and Fahey, 2011). Its intense cultivation, with irrigation and fertilization, increases the biomass yields up to 100 tons per hectare (Martín et al., 2013).
For the foregoing and in order to generate knowledge and production technologies in a cost-effective and competitive way both raw material for biodiesel and co-products such as leaves used for human consumption and moringa cake, which can be used for animal feed since it contains 60% protein (García, 2013), INIFAP, in coordination with other research institutions, carried out the project: “Research and development of moringa production to obtain biodiesel in Mexico”. Within the framework of this project, the objective of this work was to evaluate the profitability and competitiveness of the production of biodiesel with moringa grains from the integral perspective of the value chain in Chiapas and Oaxaca, Mexico, considering and evaluating the co-products that can derive as much from the agricultural phase as the industrial one, quantifying the levels of costs and profits of the agricultural and industrial sectors and contributing with elements for the formulation of policies aimed at their use.
Material and methods
The present investigation was developed during the period from 2014 to 2016, in two agroecological zones with potential for moringa plantations, in which there is a background of experimentation on agronomic aspects of the species such as evaluation of collections, planting arrangements, fertilization, pruning systems, among others, that is, have the technical support necessary to make inferences about production and marketing. The study sites were: Uxmal located in the municipality of Muna, Yucatan and the Soconusco Region, located in the state of Chiapas (Figure 1).
The municipality of Muna is located in the south west region of the state of Yucatán (Figure 1a), it borders on the south with the Sierrita and borders the following municipalities: on the north with Abala, on the south with Santa Elena, on the east with Ticul and Sacalum, to the east with Halacho, Opichen and Kopoma and to the west with the state of Campeche. Its geographical coordinates are: 20° 29’ 05” latitude north and 89° 42’ 47” west longitude and it has an area of 270.81 km2. Its population to the year 2010 was of 12 366 inhabitants.
The Soconusco is located in the extreme southeast region of the state of Chiapas, between the Sierra Madre of Chiapas to the north and the Mexican Sea to the south, bounded on the east by Guatemala (Figure 1b), it is located at coordinates 15° 18’ 56’’ of latitude north and 92° 43’ 55’’ of west longitude, covering 5 475 km² (7.2% of the territory of the state of Chiapas). Its population to the year 2010 was of 710 716 inhabitants.
Technical and economic information was collected directly in plots established for experimental purposes for four years on average, where data on plantation development, yields and production costs were recorded. For the evaluation of agricultural competitiveness, the methodology called the policy analysis matrix (MAP) originally proposed by Monke and Pearson (1989) was used; Bridge (1995); Salcedo (2007); Rodríguez et al. (2013). With the information taken in the field, the matrix of technical coefficients was structured, consisting of a table in Excel where the quantities of inputs and labor used to grow a moringa ha are specified, with respect to yields, two components were included, the grain and the production of leaves as sources of income, this was considered because there is a market for ground moringa leaves for food purposes.
The private price matrix refers to the same coefficients, but indicating their purchase price in the local market, whose information was obtained with the technicians in charge of the plots. The private budget matrix was obtained by multiplying the two previous matrices, resulting in production costs and financial indicators such as total income, total cost, net added value and competitiveness. In Figure 2, the structuring process of the calculation matrices is shown.
The preliminary financial indicators obtained by the private budget matrix were:
Total income (IT), or value of production, was the result of multiplying the yield obtained at the parcel level (Xi) by the producer's sale price (Pi).
IT= PiXi
The total cost (CT), which was the result of the sum of the costs of inputs and internal factors, given by the price of the input (Pj) multiplied by the amount of input (Yj).
CT=k=1nPjYj
Net profit (GN), which was the result of the arithmetic difference between total income and total cost.
GN= IT - CT
Cost benefit ratio (RBC), which was the result of the division total revenue between total cost, its interpretation is that for each peso invested in the activity how many weights are obtained, the mathematical expression is as follows:
RBC= IT/CT
The income analysis allowed to visualize the financial situation of the productive systems, and two indicators were generated: the added value (VA) as an efficiency indicator and the private cost relation (RCP) as an indicator of competitiveness. According to Morris (1990) and Padilla (1992), the VA is the difference between the price of a unit of product less the value of the marketable inputs that are required to produce said unit of product or put another way, it is the difference between the value of production and the costs of marketable inputs and is given by the following expression:
VA= pixi -K=1npkyk
Where VA= added value; Xi= quantity produced in tons per hectare; Yk= quantity of marketable inputs applied per hectare; Pi= sale price of the product by the producer; Pk= price of marketable inputs purchased by the producer.
To define the RCP, it was first necessary to define the cost of internal factors (CFI), this indicator expresses the part of the costs corresponding to the payment of factors that do not have a defined external market or that cannot be exported or imported so easily. such as labor and land, among others. The CFI is given by the following expression:
CFI=R=1nprzr
Where: CFI= cost of internal factors; Zr= number of internal factors applied per hectare; Pr= price of internal factors used by the producer.
The RCP was used to measure the competitiveness of the productive system in relation to the efficient use of the resources available to the producer, whose interpretation is based on the fact that producers prefer to obtain excess profits, which can be obtained if the CFI is lower than the VA at private prices, it indicates the proportional part of the VA that is destined to cover the CFI. Therefore, what is recommended for an agricultural system to remain competitive is to try to minimize RCP, keeping down the costs of tradable inputs and internal factors and obtain the highest possible VA (Puente, 1995). The RCP is given by the following expression:
RCP =r=1nprzrpixi -k=1n pkyk=CFIVA
Where: RCP= private cost ratio; CFI= cost of internal factors; VA= added value.
In order to have a comprehensive overview, the biodiesel production was economically analyzed from the perspective of the value chain (primary phase and industrial phase) by adapting the computational package called biodiesel/FAO (Da Silva et al., 2009), this system through mathematical calculations for a period of 20 years, it was possible to obtain a series of social and financial indicators of both agricultural and industrial production in an integrated manner, thereby determining economic and financial viability at the production chain level (Figure 3). The system also allowed for the preparation of sensitivity analyzes and the creation of scenarios for the comparison of different projects and the visualization of the impact of some variables with respect to these indicators.
The information of the technical coefficients of the industrial phase that fed the evaluation system was obtained by recording data from various production runs in a pilot plant owned by INIFAP, whose process is described below:
Before the extraction of the oil, the beneficiation of the grains was carried out in order to eliminate the impurities and make the extraction process more efficient, after this phase and to start the extraction process of the oil, it was necessary to prepare the raw material by means of the following procedures outlined in Figure 4.
To obtain the biodiesel, the removal of the oil was carried out by means of mechanical extraction by pressing and because the crude oil contains undesirable compounds such as phosphatides or gums, sterols, waxes, carotenoid pigments and antioxidants, a process of refinement through filtration, degumming and neutralization as shown in Figure 5.
The refined oil was converted to biodiesel, which was obtained by transesterification, which consisted in the transformation of triglycerides (vegetable oil) by the addition of alcohol (methanol or ethanol) through a catalyst to obtain esters or biodiesel plus glycerin (Posada, 2010).
Derived from this process, the coefficients of the inputs required for a liter of biodiesel were obtained, which are shown in Table 1.
Table 1 Matrix of technical coefficients for the production of biodiesel from moringa grains.
Inputs Unit per liter of biodiesel Value of the coefficient Price ($) Raw material kg 2.61 5 Electricity (extraction) kWh 0.0917 3.65 Methanol kg 0.1198 13.5 Sodium hydroxide kg 0.019 8.6 Sulfuric acid kg 0.0057 9 Resin kg 0.0013 375 Antioxidant kg 0.00214 350 Electricity (transesterification) kWh 0.032 3.65 The processing coefficient; that is, the amount of raw material that was required to obtain a liter of biodiesel according to the experimental tests was determined at a level of 2.61 kilos of moringa grains to obtain a liter of biodiesel. Additionally, the minimum sale price of the raw material for the industry was determined, which was$5.00 per kilo. An average grain yield per hectare of 2 000 kg for Yucatan and 1 160 kg for Chiapas was also considered and finally, according to Madrigal (2015), annual production cycles were considered for a period of 20 years.
The biodiesel/FAO system generated the following indicators:
Internal rate of return (TIR): mathematically it is defined as the interest rate that causes in the flow of funds of a project, that the income in equivalent values in time are equal to the expenses also in equivalent terms in time. It is defined as the discount rate that reduces to zero the net present value of the sum of a series of income and expenses (FIRA, 1993). Therefore, for an investment proposal, the TIR is the interest rate i* that satisfies the following equation:
0= VPN (i*) = (Bt-Ct)(1+i)t= (Bt-Ct)11+i*t
Where: VPN (i)= net present value at an interest rate i; Bt= total benefits in year t; Ct= total costs in year t; t= time in years, it takes values that go from t= 0 to t= n (number of periods of economic life of the project).
Net present value (VAN): the current or present value of the net cash flows of an investment project, understood as net cash flows, the difference between the current value of the cash inflows of a project and the current value of the exits (FIRA, 1993). Through, the VAN it was possible to determine if the project is acceptable or not. The net present value was calculated through the following equation:
VAN (i) = (Bt-C1t)11+it
Where: Bt= total benefits in year t; Ct= total costs in year t; t= time in years, it takes values that go from t= 0 to t= n (number of periods of economic life of the project); i= discount rate that represents the minimum required rate of return.
1t1+i = Value factor present single payment.
Balance point (PE): is the level of production in percentage or units of production that exists when costs and income are equal; at this point, the company does not experience losses or profits (Martínez et al., 2015). The following formula was used:
PE=CFP-CV
Where: PE= equilibrium point; CF= fixed costs; P= unit price; CV= unit variable costs.
Results
Economic indicators of the policy analysis matrix
In the Table 2 shows the economic indicators per hectare of the agricultural phase in the two study regions, according to this information, the productivity of moringa grains was higher in Yucatán due to better soil and temperature conditions for this species, while in Chiapas productivity was lower because the type of soil and high rainfall allowed lower yields compared to Yucatan. The monetary income from the sale of grain and dry foliage in the two study sites was favorable since the production costs were recovered and a considerable and attractive net gain was generated in both cases: the goodness of the crop was demonstrated with the results of the indicator benefit ratio cost higher than six. The competitiveness of the moringa production system was high.
Table 2 Economic indicators of the cultivation of moringa in the states of Yucatán and Chiapas.
Indicator Soconusco, Chiapas Uxmal, Yucatán
Grain yield (kg ha-1 year-1) 1 160 2 000
Leaf yield (kg ha-1 year-1) 456 456
Total income ($ha-1 year-1) 91 097 105 725 Total costs ($ ha-1 year-1) 14 154 16 901
Net profit ($ha-1 year-1) 76 943 88 824 Benefit/cost ratio 6.44 6.26 Private cost ratio 0.09 0.11 Regarding the private cost ratio indicator, in Chiapas a competitiveness (RCP) of 0.09 was obtained, which indicates that the added value reached to cover the factors of production and the producer had a net gain, in Yucatán this indicator was of 0.11 due to higher production costs, in general terms, these RCP levels showed the high competitiveness of the production of moringa in both sites, which means economic spillover and significant contribution to the regional gross domestic product (PIB). Comprehensive analysis of profitability From the integral perspective of evaluation, both of the production of raw material and its transformation into biodiesel, the results obtained for the agricultural sector were satisfactory. In Table 3 it is observed that the unit cost of moringa grain production was influenced by productivity, so that for Chiapas a production cost of$8.92 per kg of dry grain was obtained and in Yucatán the cost was $4.48, the difference is due to the higher yield obtained in Yucatan, the dry leaf of Moringa in the state of Chiapas cost$28.93 per kg, while in Yucatán $26.90. The equilibrium point was low due to the high profitability of the production system, which confirms the goodness of the project for agricultural producers. Table 3 Financial indicators of the agricultural phase of the biodiesel production project with Moringa grain in Chiapas and Yucatán. Indicator Soconusco, Chiapas Uxmal, Yucatán Cost of moringa production ($ kg-1) 8.92 4.48
Production cost sheet ($kg-1) 28.93 26.90 Breakeven (%) 6.85 4.28 TIR (%) 109.03 130.37 TRC (Years) 2.28 2.12 Net present value (thousands$) 2 435 165.72 1 508 724.88
The project proved highly profitable for the agricultural producers of both sites studied, which is consistent with the results of the policy analysis matrix. In the case of the TIR, this was 109.03% and 130.37% for Chiapas and Yucatán respectively, whose level was much higher than the opportunity cost of the capital; this situation is confirmed with the equilibrium point that was of 6.85% and 4.28% for Chiapas and Yucatan respectively and the time of recovery of capital (TRC) was a little over two years. The net present value was greater than zero.
Table 4 shows that financial indicators for the industrial phase were generally favorable, although at a level not as high as for the agricultural phase. The production cost of a liter of biodiesel with moringa grains was $8.25 for the case of Chiapas and practically the same in the case of Yucatán, while the break-even point was practically 5% for both sites. The internal rate of return was better in Yucatán with 53.33%, while in Chiapas it was 37.94% with an average capital recovery time (TRC) of 3 years. The net present value was greater than zero. Table 4 Financial indicators of the industrial phase of biodiesel production with moringa grains in Chiapas and Yucatán, Mexico. Indicator Soconusco, Chiapas Uxmal, Yucatán Cost of biodiesel production ($ L-1) 8.25 8.29
Breakeven (%) 4.97 5
TIR (%) 37.94 53.33
TRC (years) 3.44 2.58
Net present value (thousands \$) 92 322.95 128 684.78
Sensitivity analysis of the TIR
In relation to the behavior of the TIR for both agriculture and industry in the face of possible changes in the prices of moringa as a raw material for the production of biodiesel, it was observed that there is a direct relationship between the TIR of the agricultural sector and the sale price of the grain; that is to say, if the sales prices of the moringa grain increase, the agricultural TIR also increases and viceversa, therefore it is convenient for the agricultural producers that the sale price of the grain be increased since their profits would increase and for so its profitability. In contrast, the TIR of the industrial sector presented an inverse relationship with the price of moringa; that is, in the face of increases in the prices of moringa, the TIR in industry decreases and vice versa, this means that the industrialists who transform the raw material from moringa into biodiesel should benefit from the low prices of moringa, because It contributes to your profits and profitability.
In the case of the study area of Soconusco, Chiapas, it was observed that the profitability of the agricultural phase supported possible price reductions, obtaining rates of return above 100%, while in the industrial phase it is highly favored when the price of the raw material decreases, but the increase of it from 15% affects the profitability of this sector, which places this phase in a vulnerable condition. Figure 6 refers to this behavior.
In the case of the Uxmal, Yucatán study area, it was observed that, due to the good agro-ecological conditions for the production of moringa grains, the project can withstand considerable decreases in the sale price of the raw material, which places agricultural producers in a favorable situation to be able to negotiate with the industrial sector the sale price. Even if the sale price decreases 25%, the TIR continues to be favorable. The opposite situation was observed in the industrial sector, since the TIR is very sensitive to the change of prices of the moringa grain. If the price increases 25% the TIR decreases to levels below 20%, so it can be said that the profitability of the industrial phase is more vulnerable to possible increases in the price of the raw material and the industrialists would have to negotiate with the farmer’s chord prices so that both sectors earn profits. Figure 7 shows the behavior of these indicators.
Conclusions
According to this study, the cultivation of moringa in the states of Chiapas and Yucatán was a profitable and competitive activity for the primary producer, this is because it is potentially generating added value, which implies that it could trigger economic spillover in the sector rural and consequently with a significant contribution to the agricultural gross domestic product, in addition to implying net gains for the producer. In Yucatán, the agroecological conditions allowed to obtain better results of production and therefore economic, what implied greater benefit for the producer through his income in relation to Chiapas. The greater proportion of the monetary income for the cultivation of moringa comes from the use of the foliage due to the high price for its nutritional properties, it foresees a potential of important market of this coproduct.
The industrial phase that consists in transforming the moringa grains into biodiesel turned out to be profitable, but it was placed in a condition of vulnerability to possible increases in the price of the raw material; that is, industrialists would not be able to withstand increases in the price of grain. A negotiation process of the sale price of the raw material is required for both sectors to obtain profits. The cost of biodiesel production was 41% lower than the current consumer price of conventional diesel. Under the technical and economic parameters considered in this study, to supply a plant with a capacity of 20 000 liters of biodiesel per day, an area of 7 830 hectares planted with moringa in Yucatan and 13 500 hectares in Chiapas is required.
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Received: April 2018; Accepted: July 2018
§Corresponding author: [email protected].
Este es un artículo publicado en acceso abierto bajo una licencia Creative Commons
| 2021-12-07T06:09:49 |
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https://wiki.cosmos.esa.int/planck-legacy-archive/index.php?title=Beam_Window_Functions&direction=next&oldid=13254
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# Beam Window Functions
Beam window functions have computed with the Febecop Pipeline (as described there), and the QuickPol pipeline (see Hivon et al, 2017[1], and the Planck 2016 Likelihood paper[2]).
The beam window functions relate, over the full sky or over a masked sky, the angular power spectrum measured (in the absence of noise) on a map produced by a set of detectors , to the true underlying sky angular power spectrum (assumed to have isotropic statistical properties, as is the case for the CMB).
### QuickPol effective beam window functions
They are available in two forms:
• The beam window functions
such that
for X=T, E or B, and where is the pixel window function, which depends on the resolution parameter Nside (=2048 for Planck HFI maps). They are provided in FITS files, in a format compatible with HEALPix tools such as synfast and smoothing, as well as with PolSpice.
• Beam matrices ,
such that
for X,Y,X',Y'= T, E or B
### References
1. Hivon E., Mottet, S. & Ponthieu N., 2017 QuickPol: Fast calculation of effective beam matrices for CMB polarization A&A 598, A25, 2017A&A...598A..25H
2. Planck collaboration, 2018, Planck 2016 results. V. Legacy Power Spectra and Likelihoods
Cosmic Microwave background
(Planck) High Frequency Instrument
Flexible Image Transfer Specification
| 2022-07-06T22:48:34 |
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https://par.nsf.gov/biblio/10164488-asas-sn-catalogue-variable-stars-vi-all-sky-sample-scuti-stars
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The ASAS-SN catalogue of variable stars VI: an all-sky sample of δ Scuti stars
ABSTRACT We characterize an all-sky catalogue of ∼8400 δ Scuti variables in ASAS-SN, which includes ∼3300 new discoveries. Using distances from Gaia DR2, we derive period–luminosity relationships for both the fundamental mode and overtone pulsators in the WJK, V, Gaia DR2 G, J, H, Ks, and W1 bands. We find that the overtone pulsators have a dominant overtone mode, with many sources pulsating in the second overtone or higher order modes. The fundamental mode pulsators have metallicity-dependent periods, with log10(P) ∼ −1.1 for $\rm [Fe/H]\lt -0.3$ and log10(P) ∼ −0.9 for $\rm [Fe/H]\gt 0$, which leads to a period-dependent scale height. Stars with $P\gt 0.100\, \rm d$ are predominantly located close to the Galactic disc ($\rm |\mathit{ Z}|\lt 0.5\, kpc$). The median period at a scale height of $Z\sim 0\, \rm kpc$ also increases with the Galactocentric radius R, from log10(P) ∼ −0.94 for sources with $R\gt 9\, \rm kpc$ to log10(P) ∼ −0.85 for sources with $R\lt 7\, \rm kpc$, which is indicative of a radial metallicity gradient. To illustrate potential applications of this all-sky catalogue, we obtained 30 min cadence, image subtraction TESS light curves for a sample of 10 fundamental mode and 10 overtone δ Scuti stars discovered more »
Authors:
; ; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
Publication Date:
NSF-PAR ID:
10164488
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
493
Issue:
3
Page Range or eLocation-ID:
4186 to 4208
ISSN:
0035-8711
The All-Sky Automated Survey for Supernovae (ASAS-SN) provides long baseline (∼4 yr) light curves for sources brighter than V ≲ 17 mag across the whole sky. As part of our effort to characterize the variability of all the stellar sources visible in ASAS-SN, we have produced ∼30.1 million V-band light curves for sources in the Southern hemisphere using the APASS DR9 (AAVSO Photometric All-Sky Survey Data Release) catalogue as our input source list. We have systematically searched these sources for variability using a pipeline based on random forest classifiers. We have identified ${\sim } 220\, 000$ variables, including ${\sim }more » 2. ABSTRACT We report the result of searching for globular clusters (GCs) around 55 Milky Way (MW) satellite dwarf galaxies within the distance of 450 kpc from the Galactic Centre except for the Large and Small Magellanic Clouds and the Sagittarius dwarf. For each dwarf, we analyse the stellar distribution of sources in Gaia DR2, selected by magnitude, proper motion, and source morphology. Using the kernel density estimation of stellar number counts, we identify 11 possible GC candidates. Cross-matched with existing imaging data, all 11 objects are known either GCs or galaxies and only Fornax GC 1–6 among them are associated withmore » 3. We present optical photometry and spectroscopy of the Type II supernova ASASSN-14jb, together with Very Large Telescope (VLT) Multi Unit Spectroscopic Explorer (MUSE) integral field observations of its host galaxy and a nebular-phase spectrum. This supernova, in the nearby galaxy ESO 467-G051 ( z = 0.006), was discovered and followed-up by the all-sky automated survey for supernovae (ASAS-SN). We obtained well-sampled las cumbres network (LCOGTN) B V g r i and Swift w 2 m 1 w 1 u b v optical, near-UV/optical light curves, and several optical spectra in the early photospheric phases. The transient ASASSN-14jb exploded ∼2 kpc abovemore » 4. ABSTRACT We explore the synergy between photometric and spectroscopic surveys by searching for periodic variable stars among the targets observed by the Apache Point Observatory Galactic Evolution Experiment (APOGEE) using photometry from the All-Sky Automated Survey for Supernovae (ASAS-SN). We identified 1924 periodic variables among more than$258\, 000$APOGEE targets; 465 are new discoveries. We homogeneously classified 430 eclipsing and ellipsoidal binaries, 139 classical pulsators (Cepheids, RR Lyrae, and δ Scuti), 719 long-period variables (pulsating red giants), and 636 rotational variables. The search was performed using both visual inspection and machine learning techniques. The light curves were also modelled with themore » 5. ABSTRACT We characterize${\sim } 71\, 200$W Ursae Majoris (UMa) type (EW) contact binaries, including${\sim } 12\, 600$new discoveries, using All-Sky Automated Survey for SuperNovae (ASAN-SN)V-band all-sky light curves along with archival data from Gaia, 2MASS, AllWISE, LAMOST, GALAH, RAVE, and APOGEE. There is a clean break in the EW period–luminosity relation at$\rm \log (\it P/{\rm d})\,{\simeq }\,{\rm -0.30}$, separating the longer period, early-type EW binaries from the shorter period, late-type systems. The two populations are even more cleanly separated in the space of period and effective temperature, by$T_{\rm eff}=6710\,{\rm K}-1760\,{\rm K}\, \log (P/0.5\,{\rm d})\$.more »
| 2022-08-18T20:31:53 |
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https://www.zbmath.org/authors/?q=ai%3Alosert.viktor
|
zbMATH — the first resource for mathematics
Losert, Viktor
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Author ID: losert.viktor Published as: Losert, V.; Losert, Viktor External Links: MGP · Wikidata · GND
Documents Indexed: 105 Publications since 1978, including 1 Book Reviewing Activity: 32 Reviews
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Co-Authors
71 single-authored 12 Rindler, Harald 7 Lau, Anthony To-Ming 3 Bellow, Alexandra 2 Akin, Ethan 2 Gröchenig, Karlheinz 2 Grosser, Michael 2 Tichy, Robert Franz 1 Akcoglu, Mustafa A. 1 Cigler, Johann 1 Cohen, Guy 1 Ghahramani, Fereidoun 1 Jones, Roger L. 1 Kornfeld, Isaac 1 Kotzmann, Ernst 1 Lipecki, Zbigniew 1 Michor, Peter Wolfram 1 Neufang, Matthias 1 Nowak, Werner Georg 1 Pachl, Jan K. 1 Reinhold-Larsson, Karin 1 Schmidt, Klaus 1 Schneider, Rudolf 1 Spurný, Jiří 1 Steprāns, Juris 1 Wierdl, Máté
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Serials
38 Monatshefte für Mathematik 4 Pacific Journal of Mathematics 4 Transactions of the American Mathematical Society 3 Journal für die Reine und Angewandte Mathematik 3 Mathematische Annalen 3 Ergodic Theory and Dynamical Systems 2 Journal of Mathematical Biology 2 Advances in Mathematics 2 Bulletin of the London Mathematical Society 2 Colloquium Mathematicum 2 Journal of Functional Analysis 2 Journal of the London Mathematical Society. Second Series 2 Anzeiger der Österreichischen Akademie der Wissenschaften. Mathematisch-Naturwissenschaftliche Klasse 1 Mathematical Proceedings of the Cambridge Philosophical Society 1 Studia Mathematica 1 Acta Arithmetica 1 Acta Scientiarum Mathematicarum 1 Annales de l’Institut Fourier 1 Archiv der Mathematik 1 Commentarii Mathematici Helvetici 1 Compositio Mathematica 1 Illinois Journal of Mathematics 1 Inventiones Mathematicae 1 Journal of Algebra 1 Manuscripta Mathematica 1 Mathematische Nachrichten 1 Mathematische Zeitschrift 1 Proceedings of the American Mathematical Society 1 Probability Theory and Related Fields 1 Atti del Seminario Matematico e Fisico dell’Università di Modena 1 Comptes Rendus de l’Académie des Sciences. Série I 1 Bulletin of the Polish Academy of Sciences, Mathematics 1 Annals of Mathematics. Second Series 1 Lecture Notes in Pure and Applied Mathematics
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Fields
41 Abstract harmonic analysis (43-XX) 37 Topological groups, Lie groups (22-XX) 34 General and overarching topics; collections (00-XX) 27 Functional analysis (46-XX) 23 Measure and integration (28-XX) 21 Number theory (11-XX) 13 Probability theory and stochastic processes (60-XX) 12 Dynamical systems and ergodic theory (37-XX) 11 Operator theory (47-XX) 9 General topology (54-XX) 5 Group theory and generalizations (20-XX) 4 Algebraic topology (55-XX) 3 History and biography (01-XX) 2 Real functions (26-XX) 2 Difference and functional equations (39-XX) 2 Sequences, series, summability (40-XX) 2 Manifolds and cell complexes (57-XX) 2 Global analysis, analysis on manifolds (58-XX) 2 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 2 Biology and other natural sciences (92-XX) 1 Nonassociative rings and algebras (17-XX) 1 Several complex variables and analytic spaces (32-XX) 1 Harmonic analysis on Euclidean spaces (42-XX) 1 Calculus of variations and optimal control; optimization (49-XX) 1 Convex and discrete geometry (52-XX) 1 Differential geometry (53-XX) 1 Computer science (68-XX) 1 Systems theory; control (93-XX)
Citations contained in zbMATH
62 Publications have been cited 532 times in 408 Documents Cited by Year
On the second conjugate algebra of $$L_ 1(G)$$ of a locally compact group. Zbl 0608.43002
Lau, Anthony To-Ming; Losert, Viktor
1988
The weighted pointwise ergodic theorem and the individual ergodic theorem along subsequences. Zbl 0619.47004
Bellow, A.; Losert, Viktor
1985
Isometric isomorphisms between Banach algebras related to locally compact groups. Zbl 0711.43002
Ghahramani, F.; Lau, Anthony To-Ming; Losert, Viktor
1990
Dynamics of games and genes: Discrete versus continuous time. Zbl 0519.92014
Losert, V.; Akin, E.
1983
Banach modules and functors on categories of Banach spaces. Zbl 0411.46044
Cigler, Johann; Losert, Viktor; Michor, Peter
1979
The $$C^ \ast$$-algebra generated by operators with compact support on a locally compact group. Zbl 0788.22006
Lau, Anthony To-Ming; Losert, Viktor
1993
Evolutionary dynamics of zero-sum games. Zbl 0569.92014
Akin, Ethan; Losert, Viktor
1984
The derivation problem for group algebras. Zbl 1171.43004
Losert, Viktor
2008
The norm-strict bidual of a Banach algebra and the dual of Cu(G). Zbl 0527.46037
Grosser, Michael; Losert, Viktor
1984
Almost invariant sets. Zbl 0462.43002
Losert, V.; Rindler, H.
1981
Properties of the Fourier algebra that are equivalent to amenability. Zbl 0573.43004
Losert, Viktor
1984
On the structure of groups with polynomial growth. Zbl 0633.22002
Losert, Viktor
1987
Weak *-closed complemented invariant subspaces of $$L_{\infty}(G)$$ and amenable locally compact groups. Zbl 0591.43004
Lau, Anthony To-Ming; Losert, Viktor
1986
On tensor products of Fourier algebras. Zbl 0587.43001
Losert, Viktor
1984
On sequences of density zero in ergodic theory. Zbl 0587.28013
Bellow, A.; Losert, V.
1984
On the structure of groups with polynomial growth. II. Zbl 1010.22008
Losert, V.
2001
A characterization of the minimal strongly character invariant Segal algebra. Zbl 0425.43003
Losert, Viktor
1980
Conjugation-invariant means. Zbl 0629.43005
Losert, Viktor; Rindler, H.
1987
The centre of the second conjugate algebra of the Fourier algebra for infinite products of groups. Zbl 1067.22004
Lau, Anthony To-Ming; Losert, Viktor
2005
The strong sweeping out property for lacunary sequences, Riemann sums, convolution powers, and related matters. Zbl 0851.47004
Akcoglu, Mustafa; Bellow, Alexandra; Jones, Roger L.; Losert, Viktor; Reinhold-Larsson, Karin; Wierdl, Máté
1996
Weakly compact multipliers on group algebras. Zbl 1069.43001
Losert, V.
2004
Complementation of certain subspaces of $$L_{\infty}(G)$$ of a locally compact group. Zbl 0726.43006
Lau, Anthony To-Ming; Losert, Viktor
1990
Asymptotically central functions and invariant extensions of Dirac measure. Zbl 0573.43003
Losert, V.; Rindler, H.
1984
Counter-examples to some conjectures about doubly stochastic measures. Zbl 0468.28007
Losert, V.
1982
Proof of the Ghahramani-Lau conjecture. Zbl 1336.43002
Losert, Viktor; Neufang, Matthias; Pachl, Jan; Steprāns, Juris
2016
A measure space without the strong lifting property. Zbl 0402.46031
Losert, V.
1979
On the center of group $$C^*$$-algebras. Zbl 1088.22003
Losert, V.
2003
Some properties of groups without the property $$P_1$$. Zbl 0396.43007
Losert, V.
1979
The centre of the bidual of Fourier algebras (discrete groups). Zbl 1365.43003
Losert, Viktor
2016
The strong sweeping out property for convolution powers. Zbl 0972.37002
Losert, V.
2001
A class of probability measures on groups arising from some problems in ergodic theory. Zbl 0467.60011
Losert, Viktor; Schmidt, Klaus
1979
Almost constant sequences. Zbl 0404.22004
Losert, Viktor; Rindler, Harald
1979
Uniform distribution and the mean ergodic theorem. Zbl 0414.22006
Losert, V.; Rindler, H.
1978
On the existence of uniformly distributed sequences in compact topological spaces. I. Zbl 0409.10035
Losert, V.
1978
Almost constant sequences of transformations. Zbl 0381.28006
Losert, Viktor
1978
A remark on almost everywhere convergence of convolution powers. Zbl 0963.28014
Losert, Viktor
1999
Strong liftings for certain classes of compact spaces. Zbl 0501.28007
Losert, Viktor
1982
A characterization of groups with the one-sided Wiener property. Zbl 0472.43004
Losert, Viktor
1982
Teilfolgen gleichverteilter Folgen. Zbl 0371.10039
Losert, V.; Rindler, H.
1978
On derivations and crossed homomorphisms. Zbl 1209.43002
Losert, Viktor
2010
Uniform distribution in solvable groups. Zbl 0607.60008
Gröchenig, K.; Losert, V.; Rindler, H.
1986
On uniform distribution of subsequences. Zbl 0574.10050
Losert, V.; Tichy, R. F.
1986
A characterization of SIN-groups. Zbl 0561.22006
Losert, Viktor
1985
On the asymptotic distribution of the powers of $$s\times s)$$-matrices. Zbl 0498.10029
Losert, V.; Nowak, W.-G.; Tichy, R. F.
1982
A counterexample on measurable selections and strong lifting. Zbl 0432.28010
Losert, V.
1980
Dense ideals of group algebras. Zbl 0402.43002
Kotzmann, E.; Losert, V.; Rindler, H.
1979
On the existence of uniformly distributed sequences in compact topological spaces. II. Zbl 0389.10035
Losert, V.
1979
Uniformly distributed sequences on compact, separable, non metrizable groups. Zbl 0362.10039
Losert, V.
1978
Uniqueness of Cartesian products of compact convex sets. Zbl 1236.46009
Lipecki, Zbigniew; Losert, Viktor; Spurný, Jiří
2011
The set of solutions of some equation for linear recurrence sequences. Zbl 1235.11032
Losert, Viktor
2008
Separation property, Mautner phenomenon, and neutral subgroups. Zbl 1063.43005
Losert, Viktor
2004
Coboundaries and measure-preserving actions of nilpotent and solvable groups. Zbl 1055.37005
Kornfeld, Isaac; Losert, Viktor
2004
Ergodic sequences in the Fourier-Stieltjes algebra and measure algebra of a locally compact group. Zbl 0910.43001
Lau, Anthony To-Ming; Losert, Viktor
1999
A remark on the strong sweeping out property. Zbl 0868.60034
Losert, Viktor
1996
A class of sequences with a strong average property. Zbl 0585.60016
Losert, Viktor
1985
Gleichverteilte Folgen und Folgen, für die fast alle Teilfolgen gleichverteilt sind. Zbl 0558.10044
Losert, Viktor
1985
Some remarks on invariant liftings. Zbl 0579.28003
Losert, Viktor
1984
Segal algebras with functorial properties. Zbl 0518.46039
Losert, Viktor
1983
w*-closed subalgebras of $$L^\infty$$(G). Zbl 0501.43002
Losert, Viktor
1982
Équirepartition des suites definies par des semi-groupes additifs. Zbl 0465.10041
Losert, Viktor
1981
“Double multipliers” und asymptotisch invariante approximierende Einheiten. Zbl 0484.46048
Grosser, M.; Losert, V.; Rindler, H.
1980
Cyclic vectors for $$L^p(G)$$. Zbl 0452.43005
Losert, Viktor; Rindler, Harald
1980
Proof of the Ghahramani-Lau conjecture. Zbl 1336.43002
Losert, Viktor; Neufang, Matthias; Pachl, Jan; Steprāns, Juris
2016
The centre of the bidual of Fourier algebras (discrete groups). Zbl 1365.43003
Losert, Viktor
2016
Uniqueness of Cartesian products of compact convex sets. Zbl 1236.46009
Lipecki, Zbigniew; Losert, Viktor; Spurný, Jiří
2011
On derivations and crossed homomorphisms. Zbl 1209.43002
Losert, Viktor
2010
The derivation problem for group algebras. Zbl 1171.43004
Losert, Viktor
2008
The set of solutions of some equation for linear recurrence sequences. Zbl 1235.11032
Losert, Viktor
2008
The centre of the second conjugate algebra of the Fourier algebra for infinite products of groups. Zbl 1067.22004
Lau, Anthony To-Ming; Losert, Viktor
2005
Weakly compact multipliers on group algebras. Zbl 1069.43001
Losert, V.
2004
Separation property, Mautner phenomenon, and neutral subgroups. Zbl 1063.43005
Losert, Viktor
2004
Coboundaries and measure-preserving actions of nilpotent and solvable groups. Zbl 1055.37005
Kornfeld, Isaac; Losert, Viktor
2004
On the center of group $$C^*$$-algebras. Zbl 1088.22003
Losert, V.
2003
On the structure of groups with polynomial growth. II. Zbl 1010.22008
Losert, V.
2001
The strong sweeping out property for convolution powers. Zbl 0972.37002
Losert, V.
2001
A remark on almost everywhere convergence of convolution powers. Zbl 0963.28014
Losert, Viktor
1999
Ergodic sequences in the Fourier-Stieltjes algebra and measure algebra of a locally compact group. Zbl 0910.43001
Lau, Anthony To-Ming; Losert, Viktor
1999
The strong sweeping out property for lacunary sequences, Riemann sums, convolution powers, and related matters. Zbl 0851.47004
Akcoglu, Mustafa; Bellow, Alexandra; Jones, Roger L.; Losert, Viktor; Reinhold-Larsson, Karin; Wierdl, Máté
1996
A remark on the strong sweeping out property. Zbl 0868.60034
Losert, Viktor
1996
The $$C^ \ast$$-algebra generated by operators with compact support on a locally compact group. Zbl 0788.22006
Lau, Anthony To-Ming; Losert, Viktor
1993
Isometric isomorphisms between Banach algebras related to locally compact groups. Zbl 0711.43002
Ghahramani, F.; Lau, Anthony To-Ming; Losert, Viktor
1990
Complementation of certain subspaces of $$L_{\infty}(G)$$ of a locally compact group. Zbl 0726.43006
Lau, Anthony To-Ming; Losert, Viktor
1990
On the second conjugate algebra of $$L_ 1(G)$$ of a locally compact group. Zbl 0608.43002
Lau, Anthony To-Ming; Losert, Viktor
1988
On the structure of groups with polynomial growth. Zbl 0633.22002
Losert, Viktor
1987
Conjugation-invariant means. Zbl 0629.43005
Losert, Viktor; Rindler, H.
1987
Weak *-closed complemented invariant subspaces of $$L_{\infty}(G)$$ and amenable locally compact groups. Zbl 0591.43004
Lau, Anthony To-Ming; Losert, Viktor
1986
Uniform distribution in solvable groups. Zbl 0607.60008
Gröchenig, K.; Losert, V.; Rindler, H.
1986
On uniform distribution of subsequences. Zbl 0574.10050
Losert, V.; Tichy, R. F.
1986
The weighted pointwise ergodic theorem and the individual ergodic theorem along subsequences. Zbl 0619.47004
Bellow, A.; Losert, Viktor
1985
A characterization of SIN-groups. Zbl 0561.22006
Losert, Viktor
1985
A class of sequences with a strong average property. Zbl 0585.60016
Losert, Viktor
1985
Gleichverteilte Folgen und Folgen, für die fast alle Teilfolgen gleichverteilt sind. Zbl 0558.10044
Losert, Viktor
1985
Evolutionary dynamics of zero-sum games. Zbl 0569.92014
Akin, Ethan; Losert, Viktor
1984
The norm-strict bidual of a Banach algebra and the dual of Cu(G). Zbl 0527.46037
Grosser, Michael; Losert, Viktor
1984
Properties of the Fourier algebra that are equivalent to amenability. Zbl 0573.43004
Losert, Viktor
1984
On tensor products of Fourier algebras. Zbl 0587.43001
Losert, Viktor
1984
On sequences of density zero in ergodic theory. Zbl 0587.28013
Bellow, A.; Losert, V.
1984
Asymptotically central functions and invariant extensions of Dirac measure. Zbl 0573.43003
Losert, V.; Rindler, H.
1984
Some remarks on invariant liftings. Zbl 0579.28003
Losert, Viktor
1984
Dynamics of games and genes: Discrete versus continuous time. Zbl 0519.92014
Losert, V.; Akin, E.
1983
Segal algebras with functorial properties. Zbl 0518.46039
Losert, Viktor
1983
Counter-examples to some conjectures about doubly stochastic measures. Zbl 0468.28007
Losert, V.
1982
Strong liftings for certain classes of compact spaces. Zbl 0501.28007
Losert, Viktor
1982
A characterization of groups with the one-sided Wiener property. Zbl 0472.43004
Losert, Viktor
1982
On the asymptotic distribution of the powers of $$s\times s)$$-matrices. Zbl 0498.10029
Losert, V.; Nowak, W.-G.; Tichy, R. F.
1982
w*-closed subalgebras of $$L^\infty$$(G). Zbl 0501.43002
Losert, Viktor
1982
Almost invariant sets. Zbl 0462.43002
Losert, V.; Rindler, H.
1981
Équirepartition des suites definies par des semi-groupes additifs. Zbl 0465.10041
Losert, Viktor
1981
A characterization of the minimal strongly character invariant Segal algebra. Zbl 0425.43003
Losert, Viktor
1980
A counterexample on measurable selections and strong lifting. Zbl 0432.28010
Losert, V.
1980
“Double multipliers” und asymptotisch invariante approximierende Einheiten. Zbl 0484.46048
Grosser, M.; Losert, V.; Rindler, H.
1980
Cyclic vectors for $$L^p(G)$$. Zbl 0452.43005
Losert, Viktor; Rindler, Harald
1980
Banach modules and functors on categories of Banach spaces. Zbl 0411.46044
Cigler, Johann; Losert, Viktor; Michor, Peter
1979
A measure space without the strong lifting property. Zbl 0402.46031
Losert, V.
1979
Some properties of groups without the property $$P_1$$. Zbl 0396.43007
Losert, V.
1979
A class of probability measures on groups arising from some problems in ergodic theory. Zbl 0467.60011
Losert, Viktor; Schmidt, Klaus
1979
Almost constant sequences. Zbl 0404.22004
Losert, Viktor; Rindler, Harald
1979
Dense ideals of group algebras. Zbl 0402.43002
Kotzmann, E.; Losert, V.; Rindler, H.
1979
On the existence of uniformly distributed sequences in compact topological spaces. II. Zbl 0389.10035
Losert, V.
1979
Uniform distribution and the mean ergodic theorem. Zbl 0414.22006
Losert, V.; Rindler, H.
1978
On the existence of uniformly distributed sequences in compact topological spaces. I. Zbl 0409.10035
Losert, V.
1978
Almost constant sequences of transformations. Zbl 0381.28006
Losert, Viktor
1978
Teilfolgen gleichverteilter Folgen. Zbl 0371.10039
Losert, V.; Rindler, H.
1978
Uniformly distributed sequences on compact, separable, non metrizable groups. Zbl 0362.10039
Losert, V.
1978
all top 5
all top 5
Cited in 122 Serials
42 Journal of Functional Analysis 32 Proceedings of the American Mathematical Society 23 Transactions of the American Mathematical Society 22 Journal of Mathematical Analysis and Applications 19 Monatshefte für Mathematik 16 Ergodic Theory and Dynamical Systems 10 Israel Journal of Mathematics 10 Journal of Mathematical Biology 9 Advances in Mathematics 8 Bulletin of the Australian Mathematical Society 8 Mathematische Annalen 8 Semigroup Forum 8 Theoretical Population Biology 7 Mathematische Zeitschrift 6 Mathematical Proceedings of the Cambridge Philosophical Society 6 Rocky Mountain Journal of Mathematics 5 Topology and its Applications 5 Indagationes Mathematicae. New Series 4 Inventiones Mathematicae 4 Bulletin des Sciences Mathématiques 4 Acta Mathematica Sinica. English Series 4 Qualitative Theory of Dynamical Systems 3 Nonlinearity 3 Periodica Mathematica Hungarica 3 Studia Mathematica 3 Archiv der Mathematik 3 Cahiers de Topologie et Géométrie Différentielle Catégoriques 3 Compositio Mathematica 3 Journal of Economic Theory 3 Manuscripta Mathematica 3 Banach Journal of Mathematical Analysis 2 Biological Cybernetics 2 Discrete Mathematics 2 Journal d’Analyse Mathématique 2 Annales de l’Institut Fourier 2 The Annals of Probability 2 Glasgow Mathematical Journal 2 Illinois Journal of Mathematics 2 International Journal of Game Theory 2 Journal of Pure and Applied Algebra 2 Mathematika 2 Memoirs of the American Mathematical Society 2 Rendiconti del Seminario Matemàtico e Fisico di Milano 2 Acta Mathematica Hungarica 2 Journal of the American Mathematical Society 2 Expositiones Mathematicae 2 Annales de l’Institut Henri Poincaré. Probabilités et Statistiques 2 Mathematical Programming. Series A. Series B 2 Journal of Mathematical Sciences (New York) 2 Sbornik: Mathematics 2 Discrete and Continuous Dynamical Systems 2 The Journal of Fourier Analysis and Applications 1 Communications in Algebra 1 Indian Journal of Pure & Applied Mathematics 1 Mathematical Biosciences 1 Mathematical Notes 1 Russian Mathematical Surveys 1 Arkiv för Matematik 1 Bulletin of Mathematical Biology 1 Chaos, Solitons and Fractals 1 Bulletin of the London Mathematical Society 1 Bulletin de la Société Mathématique de France 1 Duke Mathematical Journal 1 Integral Equations and Operator Theory 1 Journal of Algebra 1 Journal of Approximation Theory 1 Journal of the Korean Mathematical Society 1 Journal of the London Mathematical Society. Second Series 1 Journal of Multivariate Analysis 1 Journal of Soviet Mathematics 1 Mathematische Nachrichten 1 Mathematica Slovaca 1 Proceedings of the Japan Academy. Series A 1 Rendiconti del Circolo Matemàtico di Palermo. Serie II 1 Results in Mathematics 1 Synthese 1 Theory and Decision 1 Systems & Control Letters 1 Acta Applicandae Mathematicae 1 Bulletin of the Iranian Mathematical Society 1 Revista Matemática Iberoamericana 1 MCSS. Mathematics of Control, Signals, and Systems 1 Forum Mathematicum 1 International Journal of Mathematics 1 Aequationes Mathematicae 1 Historia Mathematica 1 SIAM Journal on Applied Mathematics 1 Bulletin of the American Mathematical Society. New Series 1 Proceedings of the Indian Academy of Sciences. Mathematical Sciences 1 SIAM Journal on Optimization 1 Journal of Mathematical Imaging and Vision 1 Applied Categorical Structures 1 Journal de Théorie des Nombres de Bordeaux 1 Russian Journal of Mathematical Physics 1 Applied and Computational Harmonic Analysis 1 Finite Fields and their Applications 1 Theory and Applications of Categories 1 Journal of Difference Equations and Applications 1 Izvestiya: Mathematics 1 Documenta Mathematica ...and 22 more Serials
all top 5
Cited in 45 Fields
176 Abstract harmonic analysis (43-XX) 147 Functional analysis (46-XX) 102 Topological groups, Lie groups (22-XX) 70 Operator theory (47-XX) 60 Measure and integration (28-XX) 53 Dynamical systems and ergodic theory (37-XX) 36 Probability theory and stochastic processes (60-XX) 33 Biology and other natural sciences (92-XX) 28 Number theory (11-XX) 26 Group theory and generalizations (20-XX) 22 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 14 Harmonic analysis on Euclidean spaces (42-XX) 11 Category theory; homological algebra (18-XX) 10 Associative rings and algebras (16-XX) 8 General topology (54-XX) 7 Combinatorics (05-XX) 6 Ordinary differential equations (34-XX) 5 Operations research, mathematical programming (90-XX) 4 Linear and multilinear algebra; matrix theory (15-XX) 4 Global analysis, analysis on manifolds (58-XX) 4 Systems theory; control (93-XX) 3 History and biography (01-XX) 3 Sequences, series, summability (40-XX) 2 Mathematical logic and foundations (03-XX) 2 Order, lattices, ordered algebraic structures (06-XX) 2 Nonassociative rings and algebras (17-XX) 2 Partial differential equations (35-XX) 2 Calculus of variations and optimal control; optimization (49-XX) 2 Algebraic topology (55-XX) 2 Statistics (62-XX) 2 Information and communication theory, circuits (94-XX) 1 General and overarching topics; collections (00-XX) 1 Field theory and polynomials (12-XX) 1 Commutative algebra (13-XX) 1 $$K$$-theory (19-XX) 1 Real functions (26-XX) 1 Functions of a complex variable (30-XX) 1 Several complex variables and analytic spaces (32-XX) 1 Difference and functional equations (39-XX) 1 Approximations and expansions (41-XX) 1 Differential geometry (53-XX) 1 Numerical analysis (65-XX) 1 Computer science (68-XX) 1 Quantum theory (81-XX) 1 Statistical mechanics, structure of matter (82-XX)
Wikidata Timeline
The data are displayed as stored in Wikidata under a Creative Commons CC0 License. Updates and corrections should be made in Wikidata.
| 2021-01-24T16:51:39 |
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|
http://www.gfdl.noaa.gov/blog/isaac-held/2011/12/
|
# GFDL - Geophysical Fluid Dynamics Laboratory
As a moist parcel of air ascends it cools as it expands and does work against the rest of the atmosphere. If this were the only thing going on, the temperature of the parcel would decrease at 9.8K/km. But once the water vapor in the parcel reaches saturation some of this vapor condenses and releases its latent heat, compensating for some of the cooling (you get about 45K of warming from latent heat release when a typical parcel rises from the tropical surface to the upper troposphere). A warmer parcel contains more water vapor when it becomes saturated, so it condenses more vapor as it rises, and temperature decreases with height more slowly. That is, the moist adiabatic lapse rate, $- \partial T/\partial z$, decreases with warming.
| 2014-11-24T16:04:33 |
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|
https://www.zbmath.org/authors/?q=ai%3Ahowarth.leslie
|
# zbMATH — the first resource for mathematics
## Howarth, Leslie
Compute Distance To:
Author ID: howarth.leslie Published as: Howarth, L.; Howarth, Leslie External Links: MGP · Wikidata
Documents Indexed: 25 Publications since 1935, including 2 Books
all top 5
#### Co-Authors
17 single-authored 4 von Kármán, Theodore 2 Collinson, C. D. 2 Dryden, Hugh L. 2 Kürti, G. 2 van den Dungen, Frans H. 1 Heilbronn, Hans Arnold 1 Pérès, Joseph Jean Camille 1 Stewartson, Keith
all top 5
#### Serials
7 Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences 6 Proceedings of the Cambridge Philosophical Society 3 The Philosophical Magazine, VII. Series 2 General Relativity and Gravitation 2 Journal of Fluid Mechanics 1 Quarterly Journal of Mechanics and Applied Mathematics 1 Nature, London
all top 5
#### Fields
4 Fluid mechanics (76-XX) 2 General and overarching topics; collections (00-XX) 2 Differential geometry (53-XX) 2 Mechanics of deformable solids (74-XX) 2 Relativity and gravitational theory (83-XX) 1 Statistical mechanics, structure of matter (82-XX)
#### Citations contained in zbMATH Open
17 Publications have been cited 312 times in 299 Documents Cited by Year
On the solution of the laminar boundary layer equations. JFM 64.1452.01
Howarth, L.
1938
On the statistical theory of isotropic turbulence. Zbl 0018.15805
de Kármán, Theodore; Howarth, Leslie
1938
The boundary layer in three dimensional flow. - II. The flow near a stagnation point. Zbl 0043.39901
Howarth, L.
1951
On the statistical theory of isotropic turbulence. JFM 64.1453.03
de Kármán, T.; Howarth, L.
1938
Note on the boundary layer on a rotating sphere. Zbl 0043.40102
Howarth, L.
1951
The boundary layer in three dimensional flow. I. Derivation of the equations for flow along a general curved surface. Zbl 0042.19104
Howarth, L.
1951
Concerning the effect of compressibility on laminar boundary layers and their separation. Zbl 0032.22706
Howarth, L.
1948
Note on Killing Yano tensors admitted by spherically symmetric static space-times. Zbl 0988.83016
Howarth, L.; Collinson, C. D.
2000
On the calculation of the lift coefficient for a thin elliptic cylinder. JFM 61.0924.01
Howarth, L.
1935
Rayleigh’s problem for a semi-infinite plate. Zbl 0035.12003
Howarth, L.
1950
Generalized Killing tensors. Zbl 0978.53043
Collinson, C. D.; Howarth, L.
2000
Some aspects of Rayleigh’s problem for a compressible fluid. Zbl 0043.19302
Howarth, L.
1951
The propagation of steady disturbances in a supersonic stream bounded on one side by a parallel subsonic stream. Zbl 0040.40705
Howarth, L.
1948
The theoretical determination of the lift coefficient for a thin elliptic cylinder. JFM 61.1535.04
Howarth, L.
1935
Note on the development of the circulation around a thin elliptic cylinder. JFM 61.0924.02
Howarth, L.
1935
Advances in applied mechanics. Vol. 7. Zbl 0127.00205
Dryden, H. L. (ed.); von Kármán, Th.; Kuerti, G. (ed.); van den Dungen, F. H. (ed.); Howarth, L. (ed.)
1962
On the flow past a quarter infinite plate using Oseen’s equations. Zbl 0089.19105
Stewartson, K.; Howarth, L.
1960
Note on Killing Yano tensors admitted by spherically symmetric static space-times. Zbl 0988.83016
Howarth, L.; Collinson, C. D.
2000
Generalized Killing tensors. Zbl 0978.53043
Collinson, C. D.; Howarth, L.
2000
Advances in applied mechanics. Vol. 7. Zbl 0127.00205
Dryden, H. L. (ed.); von Kármán, Th.; Kuerti, G. (ed.); van den Dungen, F. H. (ed.); Howarth, L. (ed.)
1962
On the flow past a quarter infinite plate using Oseen’s equations. Zbl 0089.19105
Stewartson, K.; Howarth, L.
1960
The boundary layer in three dimensional flow. - II. The flow near a stagnation point. Zbl 0043.39901
Howarth, L.
1951
Note on the boundary layer on a rotating sphere. Zbl 0043.40102
Howarth, L.
1951
The boundary layer in three dimensional flow. I. Derivation of the equations for flow along a general curved surface. Zbl 0042.19104
Howarth, L.
1951
Some aspects of Rayleigh’s problem for a compressible fluid. Zbl 0043.19302
Howarth, L.
1951
Rayleigh’s problem for a semi-infinite plate. Zbl 0035.12003
Howarth, L.
1950
Concerning the effect of compressibility on laminar boundary layers and their separation. Zbl 0032.22706
Howarth, L.
1948
The propagation of steady disturbances in a supersonic stream bounded on one side by a parallel subsonic stream. Zbl 0040.40705
Howarth, L.
1948
On the solution of the laminar boundary layer equations. JFM 64.1452.01
Howarth, L.
1938
On the statistical theory of isotropic turbulence. Zbl 0018.15805
de Kármán, Theodore; Howarth, Leslie
1938
On the statistical theory of isotropic turbulence. JFM 64.1453.03
de Kármán, T.; Howarth, L.
1938
On the calculation of the lift coefficient for a thin elliptic cylinder. JFM 61.0924.01
Howarth, L.
1935
The theoretical determination of the lift coefficient for a thin elliptic cylinder. JFM 61.1535.04
Howarth, L.
1935
Note on the development of the circulation around a thin elliptic cylinder. JFM 61.0924.02
Howarth, L.
1935
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#### Cited by 483 Authors
11 Oberlack, Martin 7 Antonia, Robert Anthony 7 Grebenev, Vladimir N. 7 Vajravelu, Kuppalapalle 6 Matthaeus, William H. 5 Pop, Ioan 4 Banks, W. H. H. 4 de Divitiis, Nicola 4 Fazio, Riccardo 4 He, Jihuan 4 van Gorder, Robert Ashton 4 Weidman, Patrick D. 4 Zemach, Charles 3 Aminikhah, Hossein 3 Clark, Timothy T. 3 Danaila, Luminita 3 Dehghan Takht Fooladi, Mehdi 3 Dinarvand, Saeed 3 Djenidi, Lyazid 3 Garrett, Stephen J. 3 Gorla, Rama Subba Reddy 3 Hosseini, Reza 3 Liao, Shijun 3 Mahapatra, Tapas Ray 3 Mohapatra, Ram Narayan 3 Oughton, Sean 3 Parand, Kourosh 3 Pouquet, Annick G. 3 Pumir, Alain 3 Rosen, Gerald 3 Sibanda, Precious 3 Sidui, S. 3 Stewartson, Keith 3 Tirmizi, Ikram A. 3 Wan, Minping 3 Yapalparvi, R. 3 Zhou, Ye 2 Abbasbandy, Saeid 2 Anselmet, Fabien 2 Asaithambi, Asai 2 Bhattacharyya, Krishnendu 2 Borrelli, Alessandra 2 Chang, Henry Ker-Chang 2 Corrsin, Stanley 2 Cortell Bataller, Rafael 2 Damangir, Ebrahim 2 Eyink, Gregory L. 2 George, William K. jun. 2 Giantesio, Giulia 2 Gomez, Thomas 2 Görtler, Henry 2 Grishkov, Alexander Nikolaevich 2 Hastings, Stuart P. 2 Hayat, Tasawar 2 He, Ji-Huan 2 Holm, Darryl D. 2 Huang, Mei-Jiau 2 Ingham, Derek Binns 2 Korneev, A. I. 2 Kumari, Mahesh 2 Layek, G. C. 2 Leonard, Anthony 2 Lundgren, Thomas S. 2 Mininni, Pablo D. 2 Mitchell, Andrew Ronald 2 Moser, Robert D. 2 Motsa, Sandile Sydney 2 Nath, Girishwar 2 Ouldrouis, M. 2 Patria, Maria Cristina 2 Peters, Norbert 2 Pinton, Jean-François 2 Pullin, Dale I. 2 Ruban, Anatoly I. 2 Servidio, Sergio 2 Shidlovskiĭ, Vsevolod Pavlovich 2 Siraj-ul-Islam 2 Soewono, Edy 2 Tang, Shun Lin 2 Twizell, E. H. 2 Witting, Hermann 2 Yao, Baoheng 2 Yun, Beong In 2 Zaturska, Maria B. 1 Abdou, Mohamed Housseine 1 Abry, Patrice 1 Abu-Abdou, Khalil 1 Açık, Özgür 1 Aghakhani, M. 1 Ahmad, Faiz 1 Ahmad, Fayyaz 1 Ahmad, Latif 1 Ahmed, Jameel 1 Akbar, Noreen Sher 1 Akylas, Evangelos 1 Al-Armani, Nwaf 1 Al-Barakati, Wafaa H. 1 Alavi, Javad 1 Alexakis, Alexandros 1 Ali, Mohamed E. ...and 383 more Authors
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#### Cited in 92 Serials
31 Journal of Fluid Mechanics 28 Physics of Fluids 21 Acta Mechanica 17 European Journal of Mechanics. B. Fluids 12 ZAMP. Zeitschrift für angewandte Mathematik und Physik 10 Applied Mathematics and Computation 10 Communications in Nonlinear Science and Numerical Simulation 8 Journal of Mathematical Physics 8 Theoretical and Computational Fluid Dynamics 6 Computers and Fluids 6 Journal of Turbulence 5 International Journal of Engineering Science 5 International Journal for Numerical Methods in Fluids 5 Journal of Engineering Mathematics 5 Journal of Mathematical Analysis and Applications 5 Meccanica 4 Computers & Mathematics with Applications 4 Fluid Dynamics 4 Applied Mathematical Modelling 3 Archive for Rational Mechanics and Analysis 3 Computer Methods in Applied Mechanics and Engineering 3 Journal of Applied Mathematics and Mechanics 3 Journal of Computational Physics 3 Physica D 3 International Journal of Computer Mathematics 3 International Journal of Numerical Methods for Heat & Fluid Flow 3 Mathematical Problems in Engineering 3 Abstract and Applied Analysis 3 International Journal of Applied and Computational Mathematics 2 International Journal of Theoretical Physics 2 Journal of the Franklin Institute 2 Archiv der Mathematik 2 Journal of Computational and Applied Mathematics 2 Journal of Applied Mechanics and Technical Physics 2 Flow, Turbulence and Combustion 2 Journal of Nonlinear Mathematical Physics 2 Journal of Applied Physics 2 Physical Review, II. Series 2 Applied Scientific Research, Section A 2 Advances in Mathematical Physics 1 Modern Physics Letters A 1 International Journal of Modern Physics A 1 International Journal of Modern Physics B 1 Astronomische Nachrichten 1 Astrophysics and Space Science 1 General Relativity and Gravitation 1 Ingenieur-Archiv 1 International Journal of Heat and Mass Transfer 1 Journal of Statistical Physics 1 Mathematical Methods in the Applied Sciences 1 Mathematical Notes 1 Nonlinearity 1 Physics of Fluids 1 Reviews of Modern Physics 1 Wave Motion 1 Zeitschrift für Angewandte Mathematik und Mechanik (ZAMM) 1 Physics of Fluids, A 1 Mathematics of Computation 1 Chaos, Solitons and Fractals 1 BIT 1 Calcolo 1 International Journal for Numerical Methods in Engineering 1 Mathematika 1 Applied Mathematics and Mechanics. (English Edition) 1 Acta Applicandae Mathematicae 1 Annals of Global Analysis and Geometry 1 Numerical Methods for Partial Differential Equations 1 Mathematical and Computer Modelling 1 Applications of Mathematics 1 Communications in Numerical Methods in Engineering 1 Journal of Vibration and Control 1 Mathematical Physics, Analysis and Geometry 1 ZAMM. Zeitschrift für Angewandte Mathematik und Mechanik 1 New Journal of Physics 1 Journal of High Energy Physics 1 Living Reviews in Relativity 1 The ANZIAM Journal 1 Multiscale Modeling & Simulation 1 Journal of Statistical Mechanics: Theory and Experiment 1 Boundary Value Problems 1 PMM, Journal of Applied Mathematics and Mechanics 1 Forschung auf dem Gebiete des Ingenieurwesens 1 Acta Mechanica Sinica 1 International Journal for Computational Methods in Engineering Science and Mechanics 1 International Journal for Numerical Methods in Biomedical Engineering 1 GEM - International Journal on Geomathematics 1 ISRN Mathematical Analysis 1 S$$\vec{\text{e}}$$MA Journal 1 ISRN Applied Mathematics 1 Arabian Journal of Mathematics 1 Journal of Computational Methods in Physics 1 AMM. Applied Mathematics and Mechanics. (English Edition)
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#### Cited in 26 Fields
229 Fluid mechanics (76-XX) 40 Ordinary differential equations (34-XX) 38 Numerical analysis (65-XX) 26 Classical thermodynamics, heat transfer (80-XX) 17 Partial differential equations (35-XX) 9 Differential geometry (53-XX) 8 Relativity and gravitational theory (83-XX) 5 Probability theory and stochastic processes (60-XX) 4 Dynamical systems and ergodic theory (37-XX) 4 Statistical mechanics, structure of matter (82-XX) 2 History and biography (01-XX) 2 Approximations and expansions (41-XX) 2 Mechanics of particles and systems (70-XX) 2 Mechanics of deformable solids (74-XX) 2 Quantum theory (81-XX) 1 General and overarching topics; collections (00-XX) 1 Potential theory (31-XX) 1 Special functions (33-XX) 1 Harmonic analysis on Euclidean spaces (42-XX) 1 Integral transforms, operational calculus (44-XX) 1 Calculus of variations and optimal control; optimization (49-XX) 1 Statistics (62-XX) 1 Optics, electromagnetic theory (78-XX) 1 Astronomy and astrophysics (85-XX) 1 Geophysics (86-XX) 1 Game theory, economics, finance, and other social and behavioral sciences (91-XX)
#### Wikidata Timeline
The data are displayed as stored in Wikidata under a Creative Commons CC0 License. Updates and corrections should be made in Wikidata.
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https://www.zbmath.org/authors/?q=ai%3Awitten.edward
|
# zbMATH — the first resource for mathematics
## Witten, Edward
Compute Distance To:
Author ID: witten.edward Published as: Witten, E.; Witten, Ed; Witten, Eduard; Witten, Edward Homepage: https://www.sns.ias.edu/witten/ External Links: MGP · Wikidata · GND · MacTutor Awards: Fields Medal (1990) · Clay Research Award (2001) · Kyoto Prize in Basic Sciences (2014)
Documents Indexed: 236 Publications since 1979, including 5 Books Biographic References: 5 Publications
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#### Co-Authors
140 single-authored 11 Seiberg, Nathan 7 Gukov, Sergei 7 Vafa, Cumrun 5 Gaiotto, Davide 4 Donagi, Ron Y. 4 Klebanov, Igor R. 4 Morgan, John W. 3 Costello, Kevin Joseph 3 Dijkgraaf, Robbert H. 3 Friedman, Robert M. 3 Hořava, Petr 3 Moore, Gregory Winthrop 3 Schwarz, John H. 3 Stanford, Douglas 3 Yamazaki, Masahito 2 Atiyah, Michael Francis 2 Berkovits, Nathan J. 2 Freed, Daniel Stuart 2 Green, Michael B. 2 Jeffrey, Lisa C. 2 Maloney, Alexander 2 Mazzeo, Rafe R. 2 Polchinski, Joseph Gerard 2 Rangamani, Mukund 2 Strominger, Andrew Eben 2 Yau, Shing-Tung 1 Aharony, Ofer 1 Argyres, Philip C. 1 Axelrod, Scott 1 Bar-Natan, Dror 1 Beasley, Chris 1 Berkooz, Micha 1 Borel, Armand 1 Candelas, Pilar 1 Chaitin, Gregory J. 1 Crnković, Čedomir 1 Dedushenko, Mykola 1 Deligne, Pierre René 1 Della Pietra, Steve 1 Dolan, Louise 1 Donaldson, Simon Kirwan 1 Duff, Michael J. 1 Etingof, Pavel Il’ich 1 Frenkel, Edward V. 1 Friedan, Daniel Harry 1 Friedmann, Tamar 1 Gates, Sylvester James jun. 1 Glimm, James G. 1 Graham, C. Robin 1 Grassi, Antonella 1 Gray, Jeremy John 1 Gubser, Steven S. 1 Hanany, Amihay 1 Harlow, Daniel 1 Hirsch, Morris W. 1 Hitchin, Nigel James 1 Horowitz, Gary T. 1 Jackiw, Roman W. 1 Jaffe, Arthur Michael 1 Kachru, Shamit 1 Kapustin, Anton 1 Kazhdan, David A. 1 Kirwan, Frances Clare 1 Kronheimer, Peter Benedict 1 Lawrence-Naimar, Ruth 1 Leigh, Robert G. 1 Longo, Roberto 1 Lusztig, George 1 Mac Lane, Leslie Saunders 1 Maldacena, Juan M. 1 Maltz, Jonathan 1 Mandelbrot, Benoit B. 1 Mikhaylov, Victor S. 1 Minasian, Ruben 1 Morrison, David R. 1 Murugan, Jeff 1 Nappi, Chiara R. 1 Nekrasov, Nikita Alexandrovich 1 Pestun, Vasily 1 Plesser, Moshe Ronen 1 Rozansky, Lev 1 Ruelle, David Pierre 1 Schroers, Bernd J. 1 Schwarz, Albert S. 1 Sen, Ashoke Kumar 1 Senthil, T. 1 Sethi, Savdeep 1 Silverstein, Eva 1 Simmons-Duffin, David 1 Thom, René 1 Treiman, Sam B. 1 Uhlenbeck, Karen Keskulla 1 Wang, Chong 1 Wang, Juven 1 Wen, Xiaogang 1 Zeeman, Erik Christopher 1 Zumino, Bruno
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#### Serials
37 Nuclear Physics. B 29 Journal of High Energy Physics 18 Communications in Mathematical Physics 16 Advances in Theoretical and Mathematical Physics 7 International Journal of Modern Physics A 7 Journal of Geometry and Physics 5 Pure and Applied Mathematics Quarterly 4 Modern Physics Letters A 3 Journal of Mathematical Physics 3 Journal of Differential Geometry 3 Bulletin of the American Mathematical Society. New Series 3 Nuclear Physics, B, Proceedings Supplements 3 ICCM Notices 2 Notices of the American Mathematical Society 2 Selecta Mathematica. New Series 2 Mathematical Research Letters 2 The Asian Journal of Mathematics 2 Physical Review Letters 2 Communications in Number Theory and Physics 2 Cambridge Monographs on Mathematical Physics 1 Classical and Quantum Gravity 1 Journal of Statistical Physics 1 Letters in Mathematical Physics 1 Fortschritte der Physik 1 Advances in Mathematics 1 Philosophical Transactions of the Royal Society of London. Ser. A 1 Chinese Annals of Mathematics. Series B 1 Annals of Physics 1 Proceedings of the Royal Society of Edinburgh. Section A. Mathematics 1 Journal of Algebraic Geometry 1 Communications in Analysis and Geometry 1 Physical Review D. Series III 1 Analysis and Applications (Singapore) 1 Science 1 Confluentes Mathematici 1 Quantum Topology 1 PTEP. Progress of Theoretical and Experimental Physics
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#### Fields
214 Quantum theory (81-XX) 60 Relativity and gravitational theory (83-XX) 53 Differential geometry (53-XX) 47 Global analysis, analysis on manifolds (58-XX) 39 Algebraic geometry (14-XX) 23 Manifolds and cell complexes (57-XX) 18 Several complex variables and analytic spaces (32-XX) 9 Number theory (11-XX) 8 Nonassociative rings and algebras (17-XX) 8 Topological groups, Lie groups (22-XX) 5 Dynamical systems and ergodic theory (37-XX) 4 History and biography (01-XX) 4 $$K$$-theory (19-XX) 3 Group theory and generalizations (20-XX) 3 Functions of a complex variable (30-XX) 3 Ordinary differential equations (34-XX) 3 Algebraic topology (55-XX) 3 Mechanics of particles and systems (70-XX) 2 General and overarching topics; collections (00-XX) 2 Partial differential equations (35-XX) 2 Statistical mechanics, structure of matter (82-XX) 1 Associative rings and algebras (16-XX) 1 Functional analysis (46-XX) 1 General topology (54-XX) 1 Statistics (62-XX) 1 Information and communication theory, circuits (94-XX)
#### Citations contained in zbMATH Open
222 Publications have been cited 24,299 times in 13,992 Documents Cited by Year
Anti de Sitter space and holography. Zbl 0914.53048
Witten, Edward
1998
Quantum field theory and the Jones polynomial. Zbl 0667.57005
Witten, Edward
1989
String theory and noncommutative geometry. Zbl 0957.81085
Seiberg, Nathan; Witten, Edward
1999
Anti-de Sitter space, thermal phase transition, and confinement in gauge theories. Zbl 1057.81550
Witten, Edward
1998
Monopoles, duality and chiral symmetry breaking in $$N=2$$ supersymmetric QCD. Zbl 1020.81911
Seiberg, N.; Witten, E.
1994
Phases of $$N=2$$ theories in two dimensions. Zbl 0910.14020
Witten, E.
1993
Electric-magnetic duality, monopole condensation, and confinement in $$N=2$$ supersymmetric Yang-Mills theory. Zbl 0996.81510
Seiberg, N.; Witten, E.
1994
$$2+1$$-dimensional gravity as an exactly soluble system. Zbl 1258.83032
Witten, Edward
1988
Topological quantum field theory. Zbl 0656.53078
Witten, Edward
1988
String theory dynamics in various dimensions. Zbl 0990.81663
Witten, Edward
1995
Type IIB superstrings, BPS monopoles, and three-dimensional gauge dynamics. Zbl 0996.58509
Hanany, Amihay; Witten, Edward
1997
Erratum: ”Electric-magnetic duality, monopole condensation, and confinement in $$N=2$$ supersymmetric Yang-Mills theory”. Zbl 0996.81511
Seiberg, N.; Witten, E.
1994
Supersymmetry and Morse theory. Zbl 0499.53056
Witten, Edward
1982
Non-Abelian bosonization in two dimensions. Zbl 0536.58012
Witten, Edward
1984
Perturbative gauge theory as a string theory in twistor space. Zbl 1105.81061
Witten, Edward
2004
Superstring theory. Volume 1: Introduction. Volume 2: Loop amplitudes, anomalies and phenomenology. Zbl 0619.53002
Green, Michael B.; Schwarz, John H.; Witten, Edward
1987
Dynamical breaking of supersymmetry. Zbl 1258.81046
Witten, Edward
1981
Solutions of four-dimensional field theories via M-theory. Zbl 0934.81066
Witten, Edward
1997
Superconformal field theory on threebranes at a Calabi-Yau singularity. Zbl 0948.81619
Klebanov, Igor R.; Witten, Edward
1999
Two dimensional gauge theories revisited. Zbl 0768.53042
Witten, Edward
1992
A new proof of the positive energy theorem. Zbl 1051.83532
Witten, Edward
1981
AdS/CFT correspondence and symmetry breaking. Zbl 0958.81134
Klebanov, Igor R.; Witten, Edward
1999
Heterotic and type I string dynamics from eleven dimensions. Zbl 1004.81525
Hořava, Petr; Witten, Edward
1996
A strong coupling test of $$S$$-duality. Zbl 0964.81522
Vafa, Cumrun; Witten, Edward
1994
Electric-magnetic duality and the geometric Langlands program. Zbl 1128.22013
Kapustin, Anton; Witten, Edward
2007
Bound states of strings and $$p$$-branes. Zbl 1003.81527
Witten, Edward
1996
CFT’s from Calabi-Yau four-folds. Zbl 0984.81143
Gukov, Sergei; Vafa, Cumrun; Witten, Edward
2000
Two-dimensional gravity and intersection theory on moduli space. Zbl 0757.53049
Witten, Edward
1991
Eleven-dimensional supergravity on a manifold with boundary. Zbl 0925.81180
Hořava, Petr; Witten, Edward
1996
Topological gauge theories and group cohomology. Zbl 0703.58011
Dijkgraaf, Robbert; Witten, Edward
1990
$$S$$-duality of boundary conditions in $${\mathcal N}=4$$ super Yang-Mills theory. Zbl 1206.81082
Gaiotto, Davide; Witten, Edward
2009
Comments on string dynamics in six dimensions. Zbl 1003.81535
Seiberg, N.; Witten, E.
1996
On quantum gauge theories in two dimensions. Zbl 0762.53063
Witten, Edward
1991
Supersymmetric Yang-Mills theory and integrable systems. Zbl 0996.37507
Donagi, Ron; Witten, Edward
1996
Monopoles and four-manifolds. Zbl 0867.57029
Witten, Edward
1994
Topological sigma models. Zbl 0674.58047
Witten, Edward
1988
Small instantons in string theory. Zbl 0935.81052
Witten, Edward
1996
Black hole entropy in M-theory. Zbl 0951.83034
Maldacena, Juan; Strominger, Andrew; Witten, Edward
1997
String theory and black holes. Zbl 0900.53037
Witten, Edward
1991
Vector bundles and $$F$$ theory. Zbl 0919.14010
Friedman, Robert; Morgan, John; Witten, Edward
1997
Non-perturbative superpotentials in string theory. Zbl 0925.32012
Witten, Edward
1996
The D1/D5 system and singular CFT. Zbl 0953.81076
Seiberg, Nathan; Witten, Edward
1999
Chern-Simons gauge theory as a string theory. Zbl 0844.58018
Witten, E.
1995
Phase transitions in M-theory and F-theory. Zbl 1003.81537
Witten, Edward
1996
Five-brane effective action in $$M$$-theory. Zbl 0878.58063
Witten, Edward
1997
Gauge theory, ramification, and the geometric Langlands program. Zbl 1237.14024
Gukov, Sergei; Witten, Edward
2008
Janus configurations, Chern-Simons couplings, and the $$\theta$$-angle in $$\mathcal{N} = 4$$ super Yang-Mills theory. Zbl 1290.81065
Gaiotto, Davide; Witten, Edward
2010
Anomalies in string theory with D-branes. Zbl 1028.81052
Freed, Daniel S.; Witten, Edward
1999
D-branes and $$K$$-theory. Zbl 0959.81070
Witten, Edward
1998
Gauge dynamics and compactification to three dimensions. Zbl 1058.81717
Seiberg, N.; Witten, E.
1997
Evidence for heterotic - type I string duality. Zbl 1004.81526
Polchinski, Joseph; Witten, Edward
1996
Supersymmetric boundary conditions in $$\mathcal{N}=4$$ super Yang-Mills theory. Zbl 1178.81180
Gaiotto, Davide; Witten, Edward
2009
New $$N = 2$$ superconformal field theories in four dimensions. Zbl 1004.81557
Argyres, Philip C.; Plesser, M. Ronen; Seiberg, Nathan; Witten, Edward
1996
Quantum gravity partition functions in three dimensions. Zbl 1270.83022
Maloney, Alexander; Witten, Edward
2010
On flux quantization in $$M$$-theory and the effective action. Zbl 0908.53065
Witten, Edward
1997
Quantum field theory and the Jones polynomial. Zbl 0726.57010
Witten, Edward
1989
Strong coupling expansion of Calabi-Yau compactification. Zbl 1003.81536
Witten, Edward
1996
Elliptic genera and quantum field theory. Zbl 0625.57008
Witten, Edward
1987
Analytic continuation of Chern-Simons theory. Zbl 1337.81106
Witten, Edward
2011
Baryons and branes in anti-de Sitter space. Zbl 0958.81081
Witten, Edward
1998
Constraints on low-dimensional string compactifications. Zbl 0925.81209
Sethi, S.; Vafa, C.; Witten, E.
1996
The omega deformation, branes, integrability and Liouville theory. Zbl 1291.81265
Nekrasov, Nikita; Witten, Edward
2010
Coadjoint orbits of the Virasoro group. Zbl 0632.22015
Witten, Edward
1988
Geometric quantization of Chern-Simons gauge theory. Zbl 0697.53061
Axelrod, Scott; Della Pietra, Steve; Witten, Edward
1991
Branes and the dynamics of QCD. Zbl 0925.81388
Witten, Edward
1997
A duality web in $$2+1$$ dimensions and condensed matter physics. Zbl 1377.81262
Seiberg, Nathan; Senthil, T.; Wang, Chong; Witten, Edward
2016
Mirror manifolds and topological field theory. Zbl 0834.58013
Witten, Edward
1992
Conformal field theory of AdS background with Ramond-Ramond flux. Zbl 0965.81090
Berkovits, Nathan J.; Vafa, Cumrun; Witten, Edward
1999
Global gravitational anomalies. Zbl 0581.58038
Witten, Edward
1985
The Verlinde algebra and the cohomology of the Grassmannian. Zbl 0863.53054
Witten, Edward
1995
Analytic continuation of Liouville theory. Zbl 1306.81287
Harlow, Daniel; Maltz, Jonathan; Witten, Edward
2011
Conformal anomaly of submanifold observables in AdS/CFT correspondence. Zbl 0944.81046
Graham, C. Robin; Witten, Edward
1999
Search for a realistic Kaluza-Klein theory. Zbl 1156.83330
Witten, Eduard
1999
Five-branes and M-theory on an orbifold. Zbl 1004.81534
Witten, Edward
1996
Fermionic localization of the Schwarzian theory. Zbl 1383.83099
Stanford, Douglas; Witten, Edward
2017
M-theory dynamics on a manifold of $$G_2$$ holonomy. Zbl 1033.81065
Atiyah, Michael; Witten, Edward
2002
On holomorphic factorization of WZW and coset models. Zbl 0766.53068
Witten, Edward
1992
On the conformal field theory of the Higgs branch. Zbl 0949.81056
Witten, Edward
1997
On the Landau-Ginzburg description of $$N=2$$ minimal models. Zbl 0985.81718
Witten, Edward
1994
Wess-Zumino-Witten model based on a nonsemisimple group. Zbl 0972.81635
Nappi, Chiara R.; Witten, Edward
1993
A spacetime derivation of the Lorentzian OPE inversion formula. Zbl 1395.81246
Simmons-Duffin, David; Stanford, Douglas; Witten, Edward
2018
Current algebra and anomalies. Zbl 0604.53042
Treiman, Sam B.; Jackiw, Roman; Zumino, Bruno; Witten, Edward
1985
Dual string pairs with $$N=1$$ and $$N=2$$ supersymmetry in four dimensions. Zbl 0957.81590
Vafa, Cumrun; Witten, Edward
1996
Twistor-like transform in ten dimensions. Zbl 0608.53068
Witten, E.
1986
Covariant description of canonical formalism in geometrical theories. Zbl 0966.81533
Crnković, Čedomir; Witten, Edward
1987
Instability of the Kaluza-Klein vacuum. Zbl 0900.53036
Witten, Eduard
1982
On orbifolds with discrete torsion. Zbl 0816.53053
Vafa, Cumrun; Witten, Edward
1995
A one-loop test of string duality. Zbl 1009.81541
Vafa, Cumrun; Witten, Edward
1995
Toroidal compactification without vector structure. Zbl 0958.81065
Witten, Edward
1998
Quantization of Chern-Simons gauge theory with complex gauge group. Zbl 0717.53074
Witten, Edward
1991
$$\text{SL}(2,\mathbb Z)$$ action on three-dimensional conformal field theories with abelian symmetry. Zbl 1160.81457
Witten, Edward
2005
Rigid surface operators. Zbl 1203.81114
Gukov, Sergei; Witten, Edward
2010
Geometric Langlands from six dimensions. Zbl 1216.81129
Witten, Edward
2010
Anomalies, dualities, and topology of $$D=6\;N=1$$ superstring vacua. Zbl 0925.81335
Berkooz, Micha; Leigh, Robert G.; Polchinski, Joseph; Schwarz, John H.; Seiberg, Nathan; Witten, Edward
1996
On $$S$$-duality in abelian gauge theory. Zbl 0833.53024
Witten, E.
1995
Evidence for heterotic/heterotic duality. Zbl 1002.81524
Duff, M. J.; Minasian, R.; Witten, Edward
1996
More on supersymmetric and 2d analogs of the SYK model. Zbl 1381.81121
Murugan, Jeff; Stanford, Douglas; Witten, Edward
2017
Mirror manifolds and topological field theory. Zbl 0904.58009
Witten, Edward
1998
Quantum field theory, Grassmannians, and algebraic curves. Zbl 0636.22012
Witten, Edward
1987
Criteria for conformal invariance of $$(0,2)$$ models. Zbl 0990.81666
Silverstein, Eva; Witten, Edward
1995
Averaging over Narain moduli space. Zbl 1456.83067
Maloney, Alexander; Witten, Edward
2020
The KW equations and the Nahm pole boundary condition with knots. Zbl 1456.81311
Mazzeo, Rafe; Witten, Edward
2020
Perturbative superstring theory revisited. Zbl 1421.81101
Witten, Edward
2019
Notes on super Riemann surfaces and their moduli. Zbl 1423.32012
Witten, Edward
2019
Notes on supermanifolds and integration. Zbl 1421.58001
Witten, Edward
2019
Gauge theory and integrability. I. Zbl 1442.81050
Costello, Kevin; Witten, Edward; Yamazaki, Masahito
2019
Open strings on the Rindler horizon. Zbl 1409.83197
Witten, Edward
2019
Superstring perturbation theory via super Riemann surfaces: an overview. Zbl 1421.81102
Witten, Edward
2019
A new $$\operatorname{SU}(2)$$ anomaly. Zbl 1414.81170
Wang, Juven; Wen, Xiao-Gang; Witten, Edward
2019
A spacetime derivation of the Lorentzian OPE inversion formula. Zbl 1395.81246
Simmons-Duffin, David; Stanford, Douglas; Witten, Edward
2018
Gauge theory and integrability. II. Zbl 1405.81044
Costello, Kevin; Witten, Edward; Yamazaki, Masahito
2018
Gauge theory and integrability. I. Zbl 1405.81043
Costello, Kevin; Witten, Edward; Yamazaki, Masahito
2018
Developments in topological gravity. Zbl 1404.83001
Dijkgraaf, Robbert; Witten, Edward
2018
Integrable lattice models from gauge theory. Zbl 1457.82109
Witten, Edward
2018
More on gauge theory and geometric Langlands. Zbl 1392.81188
Witten, Edward
2018
Fermionic localization of the Schwarzian theory. Zbl 1383.83099
Stanford, Douglas; Witten, Edward
2017
More on supersymmetric and 2d analogs of the SYK model. Zbl 1381.81121
Murugan, Jeff; Stanford, Douglas; Witten, Edward
2017
Two lectures on the Jones polynomial and Khovanov homology. Zbl 1393.57004
Witten, Edward
2017
An introduction to the Web-based formalism. Zbl 1397.81241
Gaiotto, Davide; Moore, Gregory W.; Witten, Edward
2017
A duality web in $$2+1$$ dimensions and condensed matter physics. Zbl 1377.81262
Seiberg, Nathan; Senthil, T.; Wang, Chong; Witten, Edward
2016
Gapped boundary phases of topological insulators via weak coupling. Zbl 1361.81151
Seiberg, Nathan; Witten, Edward
2016
Some details on the Gopakumar-Vafa and Ooguri-Vafa formulas. Zbl 1355.81140
Dedushenko, Mykola; Witten, Edward
2016
Supermoduli space is not projected. Zbl 1356.14021
Donagi, Ron; Witten, Edward
2015
Branes and supergroups. Zbl 1326.81210
Mikhaylov, Victor; Witten, Edward
2015
Filling the gaps with PCO’s. Zbl 1388.81889
Sen, Ashoke; Witten, Edward
2015
The Feynman $$i\epsilon$$ in string theory. Zbl 1388.81610
Witten, Edward
2015
The super period matrix with Ramond punctures. Zbl 1318.83001
Witten, Edward
2015
Notes on holomorphic string and superstring theory measures of low genus. Zbl 1333.14050
Witten, Edward
2015
The Nahm pole boundary condition. Zbl 1335.81111
Mazzeo, Rafe; Witten, Edward
2014
Supersymmetry breaking effects using the pure spinor formalism of the superstring. Zbl 1333.81156
Berkovits, Nathan; Witten, Edward
2014
Super Atiyah classes and obstructions to splitting of supermoduli space. Zbl 1314.58004
Donagi, Ron; Witten, Edward
2013
Fivebranes and knots. Zbl 1241.57041
Witten, Edward
2012
Knot invariants from four-dimensional gauge theory. Zbl 1271.81108
Gaiotto, Davide; Witten, Edward
2012
Khovanov homology and gauge theory. Zbl 1276.57013
Witten, Edward
2012
Superstring theory. Volume 1: Introduction. Volume 2: Loop amplitudes, anomalies and phenomenology. Reprint of the 1987 hardback edition. Zbl 1245.53003
Green, Michael B.; Schwarz, John H.; Witten, Edward
2012
Analytic continuation of Chern-Simons theory. Zbl 1337.81106
Witten, Edward
2011
Analytic continuation of Liouville theory. Zbl 1306.81287
Harlow, Daniel; Maltz, Jonathan; Witten, Edward
2011
An algebraic construction of boundary quantum field theory. Zbl 1214.81253
Longo, Roberto; Witten, Edward
2011
A new look at the path integral of quantum mechanics. Zbl 1250.81060
Witten, Edward
2011
Janus configurations, Chern-Simons couplings, and the $$\theta$$-angle in $$\mathcal{N} = 4$$ super Yang-Mills theory. Zbl 1290.81065
Gaiotto, Davide; Witten, Edward
2010
Quantum gravity partition functions in three dimensions. Zbl 1270.83022
Maloney, Alexander; Witten, Edward
2010
The omega deformation, branes, integrability and Liouville theory. Zbl 1291.81265
Nekrasov, Nikita; Witten, Edward
2010
Rigid surface operators. Zbl 1203.81114
Gukov, Sergei; Witten, Edward
2010
Geometric Langlands from six dimensions. Zbl 1216.81129
Witten, Edward
2010
Geometric Langlands duality and the equations of Nahm and Bogomolny. Zbl 1216.81108
Witten, Edward
2010
Mirror symmetry, Hitchin’s equations, and Langlands duality. Zbl 1298.81151
Witten, Edward
2010
$$S$$-duality of boundary conditions in $${\mathcal N}=4$$ super Yang-Mills theory. Zbl 1206.81082
Gaiotto, Davide; Witten, Edward
2009
Supersymmetric boundary conditions in $$\mathcal{N}=4$$ super Yang-Mills theory. Zbl 1178.81180
Gaiotto, Davide; Witten, Edward
2009
Branes and quantization. Zbl 1247.81378
Gukov, Sergei; Witten, Edward
2009
Gauge theory, ramification, and the geometric Langlands program. Zbl 1237.14024
Gukov, Sergei; Witten, Edward
2008
Gauge theory and wild ramification. Zbl 1177.81101
Witten, Edward
2008
Geometric endoscopy and mirror symmetry. Zbl 1223.14014
Frenkel, Edward; Witten, Edward
2008
Electric-magnetic duality and the geometric Langlands program. Zbl 1128.22013
Kapustin, Anton; Witten, Edward
2007
Two-dimensional models with $$(0,2)$$ supersymmetry: perturbative aspects. Zbl 1200.17014
Witten, Edward
2007
From superconductors and four-manifolds to weak interactions. Zbl 1148.81015
Witten, Edward
2007
Surface operators in gauge theory. Zbl 1119.81078
Witten, E.
2007
Quantum Yang-Mills theory. Zbl 1194.81002
Jaffe, Arthur; Witten, Edward
2006
$$\text{SL}(2,\mathbb Z)$$ action on three-dimensional conformal field theories with abelian symmetry. Zbl 1160.81457
Witten, Edward
2005
Non-abelian localization for Chern-Simons theory. Zbl 1097.58012
Beasley, Chris; Witten, Edward
2005
The Hitchin functionals and the topological $$B$$-model at one loop. Zbl 1101.81098
Pestun, Vasily; Witten, Edward
2005
Perturbative gauge theory as a string theory in twistor space. Zbl 1105.81061
Witten, Edward
2004
Parity invariance for strings in twistor space. Zbl 1117.81120
Witten, Edward
2004
Conformal field theory in four and six dimensions. Zbl 1101.81096
Witten, Edward
2004
Proton decay in intersecting D-brane models. Zbl 1051.81059
Klebanov, Igor R.; Witten, Edward
2003
Unification scale, proton decay, and manifolds of $$G_2$$ holonomy. Zbl 1058.81059
Friedmann, Tamar; Witten, Edward
2003
Chiral ring of Sp$$(N)$$ and SO$$(N)$$ supersymmetric gauge theory in four dimensions. Zbl 1041.22011
Witten, E.
2003
Physical law and the quest for mathematical understanding. Zbl 1014.81039
Witten, Edward
2003
M-theory dynamics on a manifold of $$G_2$$ holonomy. Zbl 1033.81065
Atiyah, Michael; Witten, Edward
2002
Quantum gravity in de Sitter space. Zbl 1054.83013
Witten, Edward
2002
Singularities in string theory. Zbl 1040.81542
Witten, E.
2002
Connectedness of the boundary in the AdS/CFT correspondence. Zbl 1079.53066
Witten, Edward; Yau, S.-T.
2002
Supersymmetric index in four-dimensional gauge theories. Zbl 1019.81040
Witten, Edward
2001
Overview of $$K$$-theory applied to strings. Zbl 0980.81049
Witten, Edward
2001
Overview of $$K$$-theory applied to strings. Zbl 1003.81020
Witten, Edward
2001
The Hagedorn transition in noncommutative open string theory. Zbl 1036.81042
Gubser, S. S.; Gukov, S.; Klebanov, I. R.; Rangamani, M.; Witten, E.
2001
Anti-de Sitter space, thermal phase transition and confinement in gauge theories. Zbl 0995.83066
Witten, Edward
2001
CFT’s from Calabi-Yau four-folds. Zbl 0984.81143
Gukov, Sergei; Vafa, Cumrun; Witten, Edward
2000
Self-duality, Ramond-Ramond fields and $$K$$-theory. Zbl 0990.81626
Moore, Gregory; Witten, Edward
2000
Supersymmetric index of three-dimensional gauge theory. Zbl 0996.81061
Witten, Edward
2000
World-sheet corrections via D-instantons. Zbl 0959.81034
Witten, Edward
2000
Duality relations among topological effects in string theory. Zbl 0990.81620
Witten, Edward
2000
Noncommutative Yang-Mills theory and string theory. Zbl 1082.81516
Witten, Edward
2000
Two two-dimensional supergravity theories from Calabi-Yau four-folds. Zbl 0985.83033
Gates, S. James jun.; Gukov, Sergei; Witten, Edward
2000
Heterotic string conformal field theory and $$A$$-$$D$$-$$E$$ singularities. Zbl 0959.81082
Witten, Edward
2000
String theory and non-commutative gauge theory. Zbl 0952.81030
Witten, Edward
2000
Magic, mystery, and matrix. Zbl 1058.81001
Witten, Edward
2000
String theory and noncommutative geometry. Zbl 0957.81085
Seiberg, Nathan; Witten, Edward
1999
Superconformal field theory on threebranes at a Calabi-Yau singularity. Zbl 0948.81619
Klebanov, Igor R.; Witten, Edward
1999
AdS/CFT correspondence and symmetry breaking. Zbl 0958.81134
Klebanov, Igor R.; Witten, Edward
1999
The D1/D5 system and singular CFT. Zbl 0953.81076
Seiberg, Nathan; Witten, Edward
1999
Anomalies in string theory with D-branes. Zbl 1028.81052
Freed, Daniel S.; Witten, Edward
1999
Conformal field theory of AdS background with Ramond-Ramond flux. Zbl 0965.81090
Berkovits, Nathan J.; Vafa, Cumrun; Witten, Edward
1999
Conformal anomaly of submanifold observables in AdS/CFT correspondence. Zbl 0944.81046
Graham, C. Robin; Witten, Edward
1999
Search for a realistic Kaluza-Klein theory. Zbl 1156.83330
Witten, Eduard
1999
Vector bundles over elliptic fibrations. Zbl 0937.14004
Friedman, Robert; Morgan, John W.; Witten, Edward
1999
Connectedness of the boundary in the AdS/CFT correspondence. Zbl 0978.53085
Witten, Edward; Yau, S.-T.
1999
Quantum fields and strings: a course for mathematicians. Vols. 1, 2. Material from the Special Year on Quantum Field Theory held at the Institute for Advanced Study, Princeton, NJ, 1996–1997. Zbl 0984.00503
Deligne, Pierre (ed.); Etingof, Pavel (ed.); Freed, Daniel S. (ed.); Jeffrey, Lisa C. (ed.); Kazhdan, David (ed.); Morgan, John W. (ed.); Morrison, David R. (ed.); Witten, Edward (ed.)
1999
String theory dynamics in various dimensions. Zbl 1054.81526
Witten, Edward
1999
Vertex operators for $$\text{AdS}_3$$ background with Ramond-Ramond flux. Zbl 0957.81050
Dolan, Louise; Witten, Edward
1999
Heterotic and type I string dynamics from eleven dimensions. Zbl 1156.81446
Hořava, Petr; Witten, Edward
1999
...and 122 more Documents
all top 5
#### Cited by 10,395 Authors
91 Vafa, Cumrun 74 Witten, Edward 65 Hanany, Amihay 61 Morozov, Alexei Yurievich 57 Tachikawa, Yuji 56 Mironov, Andrei D. 53 Gaiotto, Davide 50 Gukov, Sergei 50 Lu, Hong 49 Cvetič, Mirjam 49 Morrison, David R. 48 Lüst, Dieter 44 Moore, Gregory Winthrop 44 Pope, Christopher N. 44 Szabo, Richard J. 42 Ooguri, Hirosi 42 Tseytlin, Arkady Aleksandrovich 40 Sen, Ashoke Kumar 39 Aharony, Ofer 39 Klebanov, Igor R. 37 Blumenhagen, Ralph 37 Seiberg, Nathan 37 Weigand, Timo 36 Gaberdiel, Matthias R. 36 Grimm, Thomas W. 36 Klemm, Albrecht 36 Yau, Shing-Tung 36 Yoshida, Kentaroh 35 Mariño, Marcos 34 Troost, Jan 33 Bonelli, Giulio 33 He, Yang-Hui Evariste 32 de Boer, Jan 32 D’Hoker, Eric 32 Park, Jaemo 32 Sati, Hisham 31 Pando Zayas, Leopoldo A. 31 Schäfer-Nameki, Sakura 31 Schlotterer, Oliver 31 Tanzini, Alessandro 30 Giveon, Amit 30 Nekrasov, Nikita Alexandrovich 30 Pufu, Silviu S. 30 Ramgoolam, Sanjaye 30 Sharpe, Eric R. 30 Takayanagi, Tadashi 30 Zaffaroni, Alberto 29 Gutperle, Michael 29 Kachru, Shamit 29 Kiritsis, Elias B. 29 Nuñez, Carlos 29 Taylor, Washington IV 29 Verlinde, Herman L. 28 de Mello Koch, Robert 28 Maldacena, Juan M. 28 Mekareeya, Noppadol 28 Ovrut, Burt A. 28 Razamat, Shlomo S. 28 Uranga, Angel M. 27 Duff, Michael J. 27 Gomis, Jaume 27 He, Song 27 Karch, Andreas 27 Minasian, Ruben 27 Sokatchev, Emery 27 Tomasiello, Alessandro 26 Bobev, Nokolai 26 García-Etxebarria, Iñaki 26 Lerda, Alberto 26 Liu, James T. 26 McInnes, Brett 26 Oz, Yaron 26 Yamazaki, Masahito 25 Benini, Francesco 25 Dijkgraaf, Robbert H. 25 Hayashi, Hirotaka 25 Jejjala, Vishnu 25 Kutasov, David 25 Martelli, Dario 25 Popov, Alexander D. 25 Schomerus, Volker 25 Shiu, Gary 25 Strominger, Andrew Eben 24 Amariti, Antonio 24 Balasubramanian, Vijay 24 Bianchi, Massimo 24 Billó, Marco 24 Fitzpatrick, A. Liam 24 Heckman, Jonathan J. 24 Komargodski, Zohar 24 Perlmutter, Eric 24 Reffert, Susanne 24 Valandro, Roberto 23 Aganagic, Mina 23 Becker, Melanie 23 Curio, Gottfried 23 Dasgupta, Keshav 23 Franco, Sebastián 23 Ganor, Ori J. 23 Kapustin, Anton ...and 10,295 more Authors
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#### Cited in 356 Serials
5,407 Journal of High Energy Physics 1,843 Nuclear Physics. B 764 Communications in Mathematical Physics 587 Journal of Mathematical Physics 557 International Journal of Modern Physics A 346 Journal of Geometry and Physics 296 Physics Letters. B 245 Modern Physics Letters A 222 General Relativity and Gravitation 209 Letters in Mathematical Physics 174 International Journal of Theoretical Physics 147 Theoretical and Mathematical Physics 143 Advances in Mathematics 118 Advances in High Energy Physics 111 Physical Review Letters 106 Fortschritte der Physik 86 Nuclear Physics, B, Proceedings Supplements 85 International Journal of Modern Physics D 75 Annales Henri Poincaré 74 International Journal of Geometric Methods in Modern Physics 71 Transactions of the American Mathematical Society 62 Journal of Knot Theory and its Ramifications 61 Duke Mathematical Journal 61 The European Physical Journal C. Particles and Fields 54 Classical and Quantum Gravity 50 Geometry & Topology 47 Physical Review D. Series III 46 Reviews in Mathematical Physics 44 Journal of Functional Analysis 44 Annals of Physics 42 Inventiones Mathematicae 42 Foundations of Physics 42 SIGMA. Symmetry, Integrability and Geometry: Methods and Applications 41 Mathematische Annalen 41 Bulletin of the American Mathematical Society. New Series 36 Journal of Physics A: Mathematical and Theoretical 34 Annales de l’Institut Fourier 33 Journal of Algebra 33 Mathematische Zeitschrift 33 Journal of the American Mathematical Society 33 Algebraic & Geometric Topology 31 International Journal of Mathematics 27 Topology and its Applications 26 Physics Reports 26 Differential Geometry and its Applications 25 Proceedings of the American Mathematical Society 25 Annals of Global Analysis and Geometry 25 Selecta Mathematica. New Series 24 Living Reviews in Relativity 23 Geometriae Dedicata 22 Chaos, Solitons and Fractals 22 Studies in History and Philosophy of Science. Part B. Studies in History and Philosophy of Modern Physics 21 Journal für die Reine und Angewandte Mathematik 21 New Journal of Physics 20 Journal of Pure and Applied Algebra 20 Comptes Rendus. Mathématique. Académie des Sciences, Paris 19 The Journal of Geometric Analysis 19 Communications in Contemporary Mathematics 18 Proceedings of the Steklov Institute of Mathematics 17 Science China. Mathematics 16 Calculus of Variations and Partial Differential Equations 15 Mathematical Proceedings of the Cambridge Philosophical Society 15 Reviews of Modern Physics 14 Compositio Mathematica 14 Journal of Nonlinear Mathematical Physics 13 Journal of Statistical Physics 13 Journal of Mathematical Sciences (New York) 13 Journal of Statistical Mechanics: Theory and Experiment 12 International Journal of Modern Physics B 12 Acta Applicandae Mathematicae 11 Science in China. Series A 11 Journal of Algebraic Geometry 11 Entropy 11 Advances in Mathematical Physics 11 Quantum Topology 10 Mathematical Notes 10 Physics Letters. A 10 Acta Mathematica Sinica. English Series 10 Gravitation & Cosmology 10 Symmetry 9 Functional Analysis and its Applications 9 Publications Mathématiques 9 Manuscripta Mathematica 9 Proceedings of the Japan Academy. Series A 9 Geometric and Functional Analysis. GAFA 9 Advances in Applied Clifford Algebras 9 Annals of Mathematics. Second Series 8 Memoirs of the American Mathematical Society 8 Physica D 7 Journal of Mathematical Analysis and Applications 7 Reports on Mathematical Physics 7 Michigan Mathematical Journal 7 Pacific Journal of Mathematics 7 Chinese Annals of Mathematics. Series B 7 Journal de Mathématiques Pures et Appliquées. Neuvième Série 7 Annalen der Physik. 8th Series 7 Journal of the European Mathematical Society (JEMS) 7 Czechoslovak Journal of Physics 7 Journal of Topology 7 Communications in Theoretical Physics ...and 256 more Serials
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#### Cited in 62 Fields
10,323 Quantum theory (81-XX) 5,597 Relativity and gravitational theory (83-XX) 1,882 Differential geometry (53-XX) 1,853 Algebraic geometry (14-XX) 1,435 Global analysis, analysis on manifolds (58-XX) 990 Manifolds and cell complexes (57-XX) 767 Nonassociative rings and algebras (17-XX) 578 Statistical mechanics, structure of matter (82-XX) 529 Several complex variables and analytic spaces (32-XX) 470 Partial differential equations (35-XX) 362 Mechanics of particles and systems (70-XX) 338 Dynamical systems and ergodic theory (37-XX) 255 Topological groups, Lie groups (22-XX) 238 Associative rings and algebras (16-XX) 216 Functional analysis (46-XX) 204 Number theory (11-XX) 203 Algebraic topology (55-XX) 195 Group theory and generalizations (20-XX) 175 Information and communication theory, circuits (94-XX) 147 Classical thermodynamics, heat transfer (80-XX) 133 Category theory; homological algebra (18-XX) 95 Statistics (62-XX) 94 Combinatorics (05-XX) 90 Special functions (33-XX) 88 $$K$$-theory (19-XX) 83 Linear and multilinear algebra; matrix theory (15-XX) 82 Astronomy and astrophysics (85-XX) 80 Functions of a complex variable (30-XX) 78 Ordinary differential equations (34-XX) 71 Fluid mechanics (76-XX) 70 Operator theory (47-XX) 61 Probability theory and stochastic processes (60-XX) 56 Optics, electromagnetic theory (78-XX) 36 General and overarching topics; collections (00-XX) 34 History and biography (01-XX) 32 Commutative algebra (13-XX) 21 General topology (54-XX) 20 Numerical analysis (65-XX) 20 Computer science (68-XX) 17 Geometry (51-XX) 16 Calculus of variations and optimal control; optimization (49-XX) 16 Convex and discrete geometry (52-XX) 14 Difference and functional equations (39-XX) 14 Approximations and expansions (41-XX) 13 Measure and integration (28-XX) 9 Abstract harmonic analysis (43-XX) 8 Mathematical logic and foundations (03-XX) 8 Field theory and polynomials (12-XX) 7 Real functions (26-XX) 6 Integral transforms, operational calculus (44-XX) 6 Biology and other natural sciences (92-XX) 5 Potential theory (31-XX) 5 Mechanics of deformable solids (74-XX) 4 Sequences, series, summability (40-XX) 4 Harmonic analysis on Euclidean spaces (42-XX) 4 Game theory, economics, finance, and other social and behavioral sciences (91-XX) 3 Order, lattices, ordered algebraic structures (06-XX) 2 General algebraic systems (08-XX) 2 Integral equations (45-XX) 2 Geophysics (86-XX) 2 Systems theory; control (93-XX) 1 Operations research, mathematical programming (90-XX)
#### Wikidata Timeline
The data are displayed as stored in Wikidata under a Creative Commons CC0 License. Updates and corrections should be made in Wikidata.
| 2021-06-16T07:44:02 |
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https://www.midwestern.nsw.gov.au/Community/Sustainable-living-and-environment/State-of-the-Environment
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# State of the Environment
Council develops a State of the Environment report each year, to provide a snapshot of the condition of the local environment that informs decision-making.
| 2022-10-07T15:01:22 |
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|
https://gea.esac.esa.int/archive/documentation/GEDR3/Data_processing/chap_cu5pho/sec_cu5pho_intro/ssec_cu5pho_intro_refsyst.html
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# 5.1.2 Reference System
Author(s): Dafydd W. Evans
An essential aspect of the photometric data processing is the split between internal and external calibrations. The internal calibrations bring all observations onto the same reference system, while the external calibrations provide the transformation between this internal system and an absolute one that can be interpreted physically. This general principle is applied to both the flux photometry and the BP/RP spectra. The models used for the internal calibration are described in Section 5.4.1. The external calibration model is described in Section 5.4.1.
For the internal calibration of the fluxes ($G$-band and integrated BP/RP), the reference system needs to be set up. No external data is used in the generation of these reference fluxes. The reason for only using data from the satellite is that if ground-based data is used, seasonal and hemispheric systematic effects can be introduced into the system. Also, Gaia has the potential to provide data that has better uncertainties and sky coverage than any current survey.
The internal calibration is carried out in a bootstrap manner illustrated in Figure 5.4. The initialization of the reference system is carried out on a period of data that is not affected by contamination which makes the process more stable. For the definition of this INIT period in Gaia EDR3 see Fig. 5 in Riello et al. (2020). Initially, the reference fluxes are generated for each source by accumulating all the raw (uncalibrated) fluxes from the INIT period and generating weighted mean values. Using these as an initial reference, calibrations are carried out. There then follows an iterative loop where the calibrations are used in accumulating calibrated fluxes to generate a better set of reference fluxes and the calibrations repeated.
This method converges since the observations for the sources have different calibrations applied to them and provided that each calibration is carried out with different sources. Given that there is good mixing between the calibrations and sources, i.e., more than half of the sources are observed in two or more configurations (CCD, Gate, FoV, …), this process should converge quickly.
In previous releases, a Time Link calibration was computed to reduce the impact of systematics due to varying contamination during the initialisation of the reference system. This was not required in the latest processing run as an extended period with very low contamination was available for the initialisation of the reference photometry.
A similar scheme is applied for the instrument calibration of the BP/RP spectra in that there is an iterative loop between the instrument calibration and the source update process which creates the reference spectra.
Further details can be found in Section 5.4.1 and Carrasco et al. (2016).
| 2022-01-24T23:33:25 |
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https://pos.sissa.it/344/112/
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Volume 344 - 14th European VLBI Network Symposium & Users Meeting (EVN2018) - Posters about AGN
Interstellar Scintillation Monitoring of the RadioAstron Blazars
J. Liu,* T.P. Krichbaum, H.E. Bignall, X. Liu, A. Kraus, Y. Kovalev, K. Sokolovsky, G. Cimò, A. Zensus
*corresponding author
Full text: pdf
Pre-published on: October 02, 2019
Published on: October 09, 2019
Abstract
The RadioAstron space radio telescope provides a unique opportunity to study the extreme brightness temperatures ($\mathrm{T_B}$) in AGNs with unprecedented long baselines of up to 28 Earth diameters. Since interstellar scintillation (ISS) may affect the visibilities observed with space VLBI (sVLBI), a complementary ground based flux density monitoring of the RadioAstron targets, which is performed near in time to the VLBI observation, could be beneficial. The combination/comparison with the sVLBI data can help to unravel the relative influence of source intrinsic and ISS induced effects, which in the end may alter the conclusions on the $\mathrm{T_B}$ measurements from sVLBI. Since 2013, a dedicated monitoring program has been ongoing to observe the ISS of RadioAstron AGN targets with a number of radio telescopes. Here we briefly introduce the program and present results from the statistical analysis of the Effelsberg monitoring data. We discuss the possible effects of ISS on $\mathrm{T_B}$ measurements for the RadioAstron target B0529+483 as a case study.
DOI: https://doi.org/10.22323/1.344.0112
How to cite
Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.
Open Access
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
| 2021-02-28T06:01:04 |
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https://par.nsf.gov/biblio/10120351
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Zeroes of polynomials on definable hypersurfaces: pathologies exist, but they are rare
Abstract
Given a sequence $\{Z_d\}_{d\in \mathbb{N}}$ of smooth and compact hypersurfaces in ${\mathbb{R}}^{n-1}$, we prove that (up to extracting subsequences) there exists a regular definable hypersurface $\Gamma \subset {\mathbb{R}}\textrm{P}^n$ such that each manifold $Z_d$ is diffeomorphic to a component of the zero set on $\Gamma$ of some polynomial of degree $d$. (This is in sharp contrast with the case when $\Gamma$ is semialgebraic, where for example the homological complexity of the zero set of a polynomial $p$ on $\Gamma$ is bounded by a polynomial in $\deg (p)$.) More precisely, given the above sequence of hypersurfaces, we construct a regular, compact, semianalytic hypersurface $\Gamma \subset {\mathbb{R}}\textrm{P}^{n}$ containing a subset $D$ homeomorphic to a disk, and a family of polynomials $\{p_m\}_{m\in \mathbb{N}}$ of degree $\deg (p_m)=d_m$ such that $(D, Z(p_m)\cap D)\sim ({\mathbb{R}}^{n-1}, Z_{d_m}),$ i.e. the zero set of $p_m$ in $D$ is isotopic to $Z_{d_m}$ in ${\mathbb{R}}^{n-1}$. This says that, up to extracting subsequences, the intersection of $\Gamma$ with a hypersurface of degree $d$ can be as complicated as we want. We call these ‘pathological examples’. In particular, we show that for every $0 \leq k \leq n-2$ and every sequence of natural numbers $a=\{a_d\}_{d\in \mathbb{N}}$ there is a regular, compact semianalytic more »
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Publication Date:
NSF-PAR ID:
10120351
Journal Name:
The Quarterly Journal of Mathematics
Volume:
70
Issue:
4
Page Range or eLocation-ID:
p. 1397-1409
ISSN:
0033-5606
Publisher:
Oxford University Press
1. Let $p:\mathbb{C}\rightarrow \mathbb{C}$ be a polynomial. The Gauss–Lucas theorem states that its critical points, $p^{\prime }(z)=0$ , are contained in the convex hull of its roots. We prove a stability version whose simplest form is as follows: suppose that $p$ has $n+m$ roots, where $n$ are inside the unit disk, $$\begin{eqnarray}\max _{1\leq i\leq n}|a_{i}|\leq 1~\text{and}~m~\text{are outside}~\min _{n+1\leq i\leq n+m}|a_{i}|\geq d>1+\frac{2m}{n};\end{eqnarray}$$ then $p^{\prime }$ has $n-1$ roots inside the unit disk and $m$ roots at distance at least $(dn-m)/(n+m)>1$ from the origin and the involved constants are sharp. We also discuss a pairing result: in the setting above, for $n$ sufficiently large, each of the $m$ roots has a critical point at distance ${\sim}n^{-1}$ .
2. Abstract Given $n$ general points $p_1, p_2, \ldots , p_n \in{\mathbb{P}}^r$ it is natural to ask whether there is a curve of given degree $d$ and genus $g$ passing through them; by counting dimensions a natural conjecture is that such a curve exists if and only if $$\begin{equation*}n \leq \left\lfloor \frac{(r + 1)d - (r - 3)(g - 1)}{r - 1}\right\rfloor.\end{equation*}$$The case of curves with nonspecial hyperplane section was recently studied in [2], where the above conjecture was shown to hold with exactly three exceptions. In this paper, we prove a “bounded-error analog” for special linear series on general curves; more precisely we show that existence of such a curve subject to the stronger inequality $$\begin{equation*}n \leq \left\lfloor \frac{(r + 1)d - (r - 3)(g - 1)}{r - 1}\right\rfloor - 3.\end{equation*}$$Note that the $-3$ cannot be replaced with $-2$ without introducing exceptions (as a canonical curve in ${\mathbb{P}}^3$ can only pass through nine general points, while a naive dimension count predicts twelve). We also use the same technique to prove that the twist of the normal bundle $N_C(-1)$ satisfies interpolation for curves whose degree is sufficiently large relative to their genus, and deduce from this that the number of generalmore »
3. Abstract We prove an inequality that unifies previous works of the authors on the properties of the Radon transform on convex bodies including an extension of the Busemann–Petty problem and a slicing inequality for arbitrary functions. Let $K$ and $L$ be star bodies in ${\mathbb R}^n,$ let $0<k<n$ be an integer, and let $f,g$ be non-negative continuous functions on $K$ and $L$, respectively, so that $\|g\|_\infty =g(0)=1.$ Then \begin{align*} & \frac{\int_Kf}{\left(\int_L g\right)^{\frac{n-k}n}|K|^{\frac kn}} \le \frac n{n-k} \left(d_{\textrm{ovr}}(K,\mathcal{B}\mathcal{P}_k^n)\right)^k \max_{H} \frac{\int_{K\cap H} f}{\int_{L\cap H} g}, \end{align*}where $|K|$ stands for volume of proper dimension, $C$ is an absolute constant, the maximum is taken over all $(n-k)$-dimensional subspaces of ${\mathbb R}^n,$ and $d_{\textrm{ovr}}(K,\mathcal{B}\mathcal{P}_k^n)$ is the outer volume ratio distance from $K$ to the class of generalized $k$-intersection bodies in ${\mathbb R}^n.$ Another consequence of this result is a mean value inequality for the Radon transform. We also obtain a generalization of the isomorphic version of the Shephard problem.
4. Abstract Let $\gamma(G)$ and $${\gamma _ \circ }(G)$$ denote the sizes of a smallest dominating set and smallest independent dominating set in a graph G, respectively. One of the first results in probabilistic combinatorics is that if G is an n -vertex graph of minimum degree at least d , then $$$$\gamma(G) \leq \frac{n}{d}(\log d + 1).$$$$ In this paper the main result is that if G is any n -vertex d -regular graph of girth at least five, then $$$$\gamma_(G) \leq \frac{n}{d}(\log d + c)$$$$ for some constant c independent of d . This result is sharp in the sense that as $d \rightarrow \infty$ , almost all d -regular n -vertex graphs G of girth at least five have $$$$\gamma_(G) \sim \frac{n}{d}\log d.$$$$ Furthermore, if G is a disjoint union of ${n}/{(2d)}$ complete bipartite graphs $K_{d,d}$ , then ${\gamma_\circ}(G) = \frac{n}{2}$ . We also prove that there are n -vertex graphs G of minimum degree d and whose maximum degree grows not much faster than d log d such that ${\gamma_\circ}(G) \sim {n}/{2}$ as $d \rightarrow \infty$ . Therefore both the girth and regularity conditions are required for the main result.
Let $f(z) = \sum_{n=1}^\infty a_f(n)q^n$ be a holomorphic cuspidal newform with even integral weight $k\geq 2$, level N, trivial nebentypus and no complex multiplication. For all primes p, we may define $\theta_p\in [0,\pi]$ such that $a_f(p) = 2p^{(k-1)/2}\cos \theta_p$. The Sato–Tate conjecture states that the angles θp are equidistributed with respect to the probability measure $\mu_{\textrm{ST}}(I) = \frac{2}{\pi}\int_I \sin^2 \theta \; d\theta$, where $I\subseteq [0,\pi]$. Using recent results on the automorphy of symmetric power L-functions due to Newton and Thorne, we explicitly bound the error term in the Sato–Tate conjecture when f corresponds to an elliptic curve over $\mathbb{Q}$ of arbitrary conductor or when f has square-free level. In these cases, if $\pi_{f,I}(x) := \#\{p \leq x : p \nmid N, \theta_p\in I\}$ and $\pi(x) := \# \{p \leq x \}$, we prove the following bound: $$\left| \frac{\pi_{f,I}(x)}{\pi(x)} - \mu_{\textrm{ST}}(I)\right| \leq 58.1\frac{\log((k-1)N \log{x})}{\sqrt{\log{x}}} \qquad \text{for} \quad x \geq 3.$$ As an application, we give an explicit bound for the number of primes up to x that violate the Atkin–Serre conjecture for f.
| 2023-02-05T15:04:19 |
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|
https://www.noblemushtak.com/blog/math-puzzle-mar-29
|
All content on this site is available under the Creative Commons Attribution 4.0 International license:
Math Puzzle from March 29, 2019
Can you solve a differential equation in electrical engineering?
Written on by Noble Mushtak
The following was a puzzle presented to Marshwood GT students on March 29, 2019. Have fun doing math!
In AP Calculus AB, you learn about separable differential equations, which can seem like a really abstract technique which is not very practical. However, today, differential equations like these can actually be a very useful tool in physics and electrical engineering!
In this riddle, we're going to look at an RC circuit, which is a circuit with a charged capacitor and a resistor in a series circuit:
(Image from Wikimedia)
In terms of $$Q_0$$, the initial charge on the capacitor, $$C$$, the capacitance of the capacitor, and $$R$$, the resistance of the resistor, find an expression for $$Q(t)$$, the charge on the capacitor as a function of time.
Part 0: Most of you probably understand what a resistor is from high school physics, but some of you may have no idea what a capacitor is, which is important to solving this riddle. One simple way to think of a capacitor is as an electrical component which stores electrical potential energy, or voltage. A capacitor stores electrical potential energy by storing charge on two opposite plates, as shown in the picture below:
Here, the separation of the positive charge on the top plate and the negative charge on the bottom plate leads to an electric field which stores electrical potential energy. However, how do we calculate the voltage $$V$$ stored in the capacitor from the charge $$Q$$ on the capacitor's plate? It turns out that the voltage is actually directly proportional to the charge, and the constant of proportionality is called the capacitance, $$C$$, of the capacitor:
$$C=\frac{Q}{V}$$
Now, solve for the potential difference across the capacitor.
Part 1: Now that we've covered capacitors, let's move onto resistors. In high school physics, many of you learned about Ohm's Law, which says that the current flowing through the resistor is:
$$I=\frac{V}{R}$$
where $$V$$ is the voltage potential drop across the resistor and $$R$$ is the resistance of the resistor.
Now, in the RC circuit, let's think about where this current is coming from. Since all we have is a resistor and a capacitor, any current that flows through the resistor must also flow through the capacitor since current flows through the whole circuit. However, if current flows from the positively-charged plate to the negatively-charged plate of the capacitor, then the positively-charged plate must be losing charge, or becoming less positive, while the negatively-charged plate is gaining charge, or becoming less negative. This ultimately means that the current flowing through the resistor is the rate of decrease in $$Q$$, the charge in the capacitor, so we find that:
$$-\frac{dQ}{dt}=\frac{V}{R}$$
Now, solve for the voltage potential drop across the resistor.
Part 2: Kirchoff's loop rule says that around any loop in an electrical circuit, the sum of voltage sources, or EMFs, equals the sum of voltage potential drops. Thus, using your answers from Part 0 and Part 1, write down the differential equation that you find from Kirchoff's loop rule. Then, solve the differential equation for $$Q$$ as a function of time $$t$$, using the initial condition $$Q(0)=Q_0$$.
Click here to check your answer.The differential equation is $$\frac{Q}{C}=-R\frac{dQ}{dt}$$ and the solution is $$Q=Q_0e^{-\frac{t}{RC}}$$.
Messenger
| 2022-09-26T19:55:45 |
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https://control.com/textbook/electric-power-measurement-and-control/distance-21-protection/
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# Distance (21) Protection
## Chapter 25 - Electric Power Measurement and Control Systems
A form of protection against faults on long-distance power lines is called distance relaying, so named because it is actually able to estimate the physical distance between the relay’s sensing transformers (PTs and CTs) and the location of the fault. In this way, it is a more sophisticated form of fault detection than simple overcurrent (e.g. 50 or 51 relay). The ANSI/IEEE number code designation for distance relaying is 21.
### Zone overreach and underreach
In order to understand the rationale for distance relaying on transmission lines, it is useful to recognize the limitations of simple overcurrent (50/51) protection. Consider this single-line diagram of a transmission line bringing power from a set of bus-connected generators to a substation at some remote distance. For simplicity’s sake, only one protective relay is shown in this diagram, and that is for breaker “F” feeding the transmission line from the generator bus:
The purpose of the overcurrent relay tripping breaker “F” is to protect the transmission line and associated equipment from damage due to overcurrent in the event of a fault along that line, and so the relay must be set appropriately for the task. The amount of fault current this relay will see depends on several factors, one of them being the location of the fault along the transmission line. If we imagine a fault occurring on the line near breaker “F,” the fault current will be relatively high because it is close to the generator bus and therefore experiences little transmission line impedance to limit current. Conversely, if we imagine a fault farther out on the transmission line (closer to breaker “G”), the amount of current caused by the fault will be less, even for the exact same type of fault, simply due to the added series impedance of the transmission line’s length (if $$I = {V \over Z}$$ and $$Z$$ increases while line voltage $$V$$ remains the same, $$I$$ must decrease). Any similar fault further downstream of the generators – such as a fault in one of the transformers in the substation – will draw even less current through breaker “F” than a similar fault on the transmission line for the same reason of greater series impedance.
An important concept in protective relaying is that of protection zones. Protective relays exist to protect the power system from damage due to faults, and they do so by tripping circuit breakers to interrupt the flow of power to a fault. However, in the interest of maintaining power to customers, it is best for protective relays to only trip those breakers necessary to clear the fault, and no more. Thus, protective relays are designed to trip specific breakers to protect limited “zones” within the system. In this next single-line diagram, we show the same system with rectangular zones overlaid on the system components:
This zone diagram makes it clear that breaker “F” and its associated overcurrent relay should only act to protect the transmission line from fault-induced damage. If a fault happens to occur within one of the transformer zones within the substation, we would prefer that fault be cleared by the protective relays and breakers for that transformer alone (i.e. either breakers “H” and “J” or breakers “I” and “K” depending on which transformer faults), in order that power be maintained in the rest of the system. This means the overcurrent relay controlling breaker “F” needs to be sensitive to faults within the transmission line zone, but insensitive to faults lying outside of the transmission line zone. If the 50/51 relay happened to overreach its zone and trip breaker “F” because of current sensed from a fault in one of the substation transformers, it would unnecessarily cut power to the entire substation, with a loss of power to all loads fed by that substation.
At first, the problem of overreaching may seem simple to solve: just calculate the maximum fault current in the transmission line due to any worst-case fault outside of that zone, and be sure to set the overcurrent relay so that it will only trip at some current greater than that amount, or set it so it will trip after a longer time delay than the substation relay(s) will trip, to give the substation relays a chance to clear the fault first.
The weakness of this approach is that fault location is not the only factor influencing fault current magnitude. Another important variable is the number of generators in service at the time of the fault. If one or more of the generators happens to go off-line, it reduces the generator bus’s ability to supply current to a fault. Another way of saying this is that the power source’s impedance changes with the number of generators on-line. This means any given fault downstream of breaker “F” will cause less fault current than it would if all generators were on-line.
This causes a problem for the “reach” of the overcurrent relay controlling breaker “F.” With reduced current capacity from the generator bus, the same relay setting that worked well to protect the transmission line zone will now be too high for faults lying toward the far end of that line. In other words, the overcurrent relay may underreach and fail to trip breaker “F” because the amount of fault current for a transmission line fault is now less than what the relay has been set to protect against, and all because we happen to have fewer generators on-line to supply power. The impedance of the transmission line and fault may be precisely the same as before, but the overcurrent relay will not trip because the circuit’s total impedance has changed due to fewer generators being on-line.
We see that the location of a fault within a long-distance power distribution system cannot be reliably detected by sensing current alone. In order to provide more consistent and reliable zone protection for the transmission line, we need a form of protection better able to discriminate fault location. One such method is to measure the impedance of the protected zone, based on current and voltage measurements at the entry point of power into that zone. This is the fundamental concept of distance protection: calculating the impedance of just the protected zone, and acting to trip breakers feeding power to that zone if the impedance suggests a fault within the boundaries of that zone.
### Line impedance characteristics
Capacitance, inductance, and resistance are all naturally present along miles of power line conductors: capacitance due to electric fields existing within the separation of the lines from one another and from earth ground by the dielectric of porcelain insulators and air; inductance due to the magnetic fields surrounding the lines as they carry current; and resistance from the metal conductors’ length.
The capacitive nature of a power line is evident when that line is open-circuited (i.e. no load connected). For the next few schematic diagrams, only a single phase (one “hot” conductor and one “neutral” conductor) will be represented for the sake of simplicity:
Here, an oscilloscope shows the relative magnitudes and phase shifts of the voltage and current waveforms, allowing us to make determinations of total circuit impedance ($$Z = {V \over I}$$).
Under typical load conditions, the resistance of the load draws a much greater amount of current than an open-circuited line draws due to its own capacitance. More importantly, this current is nearly in-phase with the voltage because the load resistance dominates circuit impedance, being substantially greater than the series reactance caused by line inductance while being substantially less than the parallel capacitive reactance:
A significant fault behaves like a very low resistance connected in parallel. This not only decreases total circuit impedance but also shifts the phase angle closer toward $$+90^{o}$$ because now the line inductive reactance is substantial compared to the resistance of the fault. Real transmission lines tend to exhibit shorted impedance phase angles nearer 70 degrees rather than 90 degrees, owing to the effects of line resistance. The exact line impedance phase angle depends on conductor size and separation:
Since line inductance is a fairly linear function of line distance (a longer power line means more inductance, given a fixed inductance-per-mile value), and this inductive reactance is the dominant factor limiting fault current, the magnitude of the fault current becomes an approximate indication of distance between the instrument transformers and the fault.
### Using impedance diagrams to characterize faults
Oscilloscope displays showing the raw voltage and current waveforms are clumsy representations of line impedance. Better visual representations for impedance exist, the most popular being a phasor diagram for line impedance with resistance ($$R$$) on the horizontal axis and reactance ($$X$$) on the vertical axis, commonly referred to as an R-X diagram. The three line examples shown in the previous section using the oscilloscope are shown in phasor format here:
Keep in mind that these phasors represent impedance, and as such a short-circuited (faulted) condition is shown as a short phasor, while an unloaded condition is shown as a long phasor. It should also be noted that these impedances, while calculated from measurements of voltage and current, do not change unless the line, load, or fault characteristics change. If the system voltage were to sag due to a generator problem, for example, the impedance phasor representing the combined effects of line and load impedance would not be altered. Any protective relay operating on impedance would therefore ignore such changes, and trip only if the line’s characteristics were to change. This is precisely the behavior we need from a “distance” relay, enabling it to discriminate line faults better than a simple overcurrent relay ever could.
For a normal load condition, the impedance phasor will be significantly longer than that of the line’s full length (i.e. much higher impedance) with an angle significantly less than that of the line impedance alone:
Short-circuit faults at various locations along a transmission line will cause the impedance phasor to vary primarily in magnitude and angle. Recall that during fault conditions, the resistance and reactance of the power line itself is the dominant impedance limiting fault current. The actual fault is predominantly resistive, with a very small impedance value.
For a fault far removed from the relay, the impedance phasor will be long (i.e. relatively high impedance) with angle nearly equal to that of the line impedance alone:
For a fault closer to the relay, the impedance phasor will be short (i.e. low impedance) with angle slightly less than that of the line impedance alone:
The goal of a distance relay (ANSI/IEEE code 21) is to trip its circuit breaker(s) if a fault occurs within its programmed “reach” and to ignore both normal operating loads and faults lying outside its reach.
If additional sources of electrical power are connected to the far end of the transmission line, it is possible for the distance relay to sense reverse power flow. Consider a case where a short-circuit fault occurs on the generator bus shown in this single-line diagram:
A fault to the left of the distance relay manifests as high current and low voltage just like a fault on the transmission line, but since the current waveform is inverted (180$$^{o}$$ phase shift) due to the opposite direction of fault current, the impedance phasor ends up in an entirely different quadrant of the R-X diagram. If the goal of the distance relay is to protect the transmission line, we need it to ignore such faults, because to operate on such a fault would be an example of overreach, the distance relay “reaching into” the generator bus zone where it should be concerned with the transmission line zone.
Each of the R-X diagram’s quadrants may be labeled in terms of power direction and power factor, either “lagging” (predominantly inductive) or “leading” (predominantly capacitive):
### Distance relay characteristics
A primitive electromechanical impedance relay design for detecting faults along long-distance transmission lines uses a simple balance-beam mechanism to sense when the ratio of line current to line voltage ($$I \over V$$) becomes excessive. It will trip if ever the impedance became too small (i.e. too much $$I$$ and too little $$V$$):
This relay’s operating coil (OC) is energized by a current transformer signal, while the restraint coil (RC) is energized by a potential transformer signal. During normal and unloaded operation, when voltage is high and current is moderate-to-low, the attractive force exerted on the beam by the restraint coil’s magnetic field exceeds the attractive force exerted on the beam by the operating coil’s magnetic field, and the trip contact remains open. If, however, a fault condition occurs on the transmission line, current will dramatically increase while voltage decreases. This combination of changes causes the operating coil’s magnetic attraction to exceed that of the restraint coil, causing the beam to tilt in a clockwise rotation, closing the trip contact to send a DC tripping signal to the circuit breaker’s trip coil.
An important characteristic of this crude impedance relay design is that it is insensitive to phase shift between voltage and current. In other words, it does not discriminate between line impedance values having different phase angles, but will trip based solely on a minimum impedance magnitude.
The “reach” of this impedance relay may be plotted on an R-X phasor diagram as a circle centered around the origin of the graph:
Any line condition placing the impedance phasor tip within this circle will cause the relay to trip. Any line condition placing the impedance phasor tip outside this circle will cause the relay to be restrained (i.e. it will not trip). Thus, the reach of this relay is represented by the radius of the circle sketched on the R-X diagram.
As you can see, this design of distance relay will trip for reverse-power conditions just as easily as it will trip for forward-power conditions. Since we generally wish to de-sensitize distance relays from “reaching backward” into a reverse protection zone, we must find some way to limit the impedance relay’s tripping sensitivity in the reverse direction.
For the primitive balance-beam design, one solution to the problem of reverse-power sensitivity is to use a directional relay in conjunction with the distance relay to block the distance relay’s action during reverse-power conditions. The trip contact of a directional relay could be wired in series with the trip contact of the impedance relay, such that the only way to trip the breaker is if both the impedance relay and the directional relay agree. We may represent this blocking behavior by drawing a line called a blinder on the R-X diagram showing a threshold beyond which the impedance relay cannot operate:
Phase-shifting components inside the directional relay mechanism tilt its blinder characteristic slightly clockwise from its natural (horizontal) characteristic. As you can see, the blinder prevents all operation in the lower-left quadrant, restricting operation of the impedance relay primarily to the upper-right and upper-left quadrants, with only a small portion of the lower-right quadrant active.
Blocking the impedance relay’s action using a directional relay is a crude solution for a crude relay design. Much better distance relay characteristics have been developed since.
A major breakthrough in distance relay design came with the advent of the induction cup mechanism. This is similar in design to the induction disk mechanism explained in the section on time-overcurrent relays, but designed to operate very quickly rather than very slowly. An induction cup mechanism closely resembles a two-phase induction motor, where a small cup-shaped metal rotor is surrounded by two sets of electromagnet poles. Maximum torque will be induced on the rotor when the stators’ magnetic fields are 90 degrees phase-shifted from one another in time. When a positive torque is applied to the cup, it rotates on its axis to close a trip contact, sending DC power to the circuit breaker’s trip coil:
The amount of torque induced on the rotor (cup) is described by the following formula:
$\tau = VI \cos (\theta - \phi) - KV^2$
Where,
$$\tau$$ = Torque exerted on induction cup
$$V$$ = Line voltage
$$I$$ = Line current
$$\theta$$ = Phase angle of voltage with respect to current
$$\phi$$ = Phase angle of maximum rotor torque
$$K$$ = Restraint constant of relay
Algebraically solving for the relay constant $$K$$ at a point of zero torque (the pick-up value for the relay) yields units of mho, or inverse ohms, which is why this mechanism is called a “mho element”:
$0 = VI \cos (\theta - \phi) - KV^2$
$0 = {I \over V} \cos (\theta - \phi) - K$
$K = {I \over V} \cos (\theta - \phi)$
$K = \left[{\hbox{Amps} \over \hbox{Volts}}\right] [\hbox{unitless}]$
$K = \left[\hbox{Mhos}\right]$
With no phase-shifting capacitor, this mechanism will be maximally sensitive to impedance values of $$+90^{o}$$, with a characteristic resembling a circle passing through the origin of an R-X diagram:
This relay’s reach is defined as any impedance falling within the circle, just as we defined the reach of the impedance relay. The difference here, of course, is that the “mho” distance relay is entirely insensitive to conditions within the lower quadrants of the R-X diagram.
With the addition of the phase-shifting capacitor to the induction cup polarizing coil circuit, the circular characteristic becomes tilted. Ideally, the angle of this tilt is set to match the impedance phasor angle of the transmission line so as to make the relay maximally sensitive to faults along the line.
With a tilted axis, the longest chord within the circle beginning at the origin of the R-X diagram is one matching the axis of tilt. Therefore, the highest impedance value capable of operating the relay and tripping the circuit breaker is one where the phase angle matches the tilt: indicative of a low-resistance fault at the end of a transmission line, assuming the circle’s diameter is proportional to the length of that line. Measured impedances at any other angle must be lower (i.e. a “heaver” loading condition) in order to operate the distance relay and trip the breaker.
If we compare circle characteristics for the simple impedance relay versus the “mho” relay capable of tripping at the same end-of-line fault condition, we see a remarkable contrast:
Both relays have the exact same reach at the transmission line’s impedance angle, but the impedance relay’s reach extends omnidirectionally for all phase angles and power flow directions, while the mho relay’s reach is optimized for the forward power direction and the line’s impedance, making it far more selective to faults along that line.
In some applications it is desirable to have the distance relay sensitized to certain values of reverse impedance (i.e. the lower-left quadrant on the R-X diagram). The induction cup relay mechanism is capable of having its circular reach characteristic “offset” with additional components so that the circle covers part of every quadrant like this:
Another variation on the “mho” characteristic is to equip the distance relay with multiple elements, each one with a different reach. The purpose of this is to provide backup protection for other zones by allowing the distance relay to overreach its primary protection zone:
Since distance relays trip whenever the tip of the impedance phasor falls within the prescribed area on the R-X diagram, at first it may seem as though zones 1 and 2 are pointlessly redundant to zone 3, since any fault lying within one of the inner zones will certainly be within the reach of the furthest zone. Indeed, this would be the case if all three distance elements operated at the same speed. However, if the zone 2 reach is purposely delayed in its action to be slower than zone 1, and zone 3 purposely delayed to make it slower than zone 2, the distance relay will serve to provide remote backup protection for the substation bus and transformer zones in the event the protective relays and/or breakers for those zones fail to properly clear a fault.
The following photograph shows a pair of Westinghouse electromechanical distance relays mounted next to a pair of time-delay units, each timer providing a different amount of delay for each of the two zones of protection afforded by the distance relays:
In the age of microprocessor relays, this design philosophy of physically wiring time-delay relays to the outputs of electromechanical protective relays for multi-zone protection may seem archaic, but it represents standard practice in distance relaying for a number of decades. Of course, modern microprocessor-based distance relays are able to perform all the necessary zone timing functions along with distance-sensing fault detection within the same unit, and do so with a degree of precision unthinkable with electromechanical relays.
Modern microprocessor-based distance relays are not constrained to circular reach characteristics either, and thus may be programmed to implement a variety of interesting reach functions. Although the traditional “mho” characteristic is still available as an option within digital distance relays, another form of reach called the quadrilateral (or “quad” for short) is often provided, whereby the distance relay may be configured to trip for any impedance phasor lying within a four-sided boundary:
Another common option within digital distance relays is the load encroachment blocking characteristic, designed to prevent relay tripping on heavy (legitimate) loads that might otherwise fall within the reach of the distance relay’s characteristic:
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Published under the terms and conditions of the Creative Commons Attribution 4.0 International Public License
| 2021-01-25T18:22:54 |
{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 1, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.6010125279426575, "perplexity": 1442.7328854146165}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 20, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703587074.70/warc/CC-MAIN-20210125154534-20210125184534-00153.warc.gz"}
|
https://pdglive.lbl.gov/DataBlock.action?node=S018M&home=sumtabB
|
# ${{\boldsymbol \Lambda}}$ MASS INSPIRE search
The fit uses ${{\mathit \Lambda}}$, ${{\mathit \Sigma}^{+}}$, ${{\mathit \Sigma}^{0}}$, ${{\mathit \Sigma}^{-}}$ mass and mass-difference measurements.
VALUE (MeV) EVTS DOCUMENT ID TECN COMMENT
$\bf{ 1115.683 \pm0.006}$ OUR FIT
$\bf{ 1115.683 \pm0.006}$ OUR AVERAGE
$1115.678$ $\pm0.006$ $\pm0.006$ 20k
1994
SPEC ${{\mathit p}}{{\mathit p}}$ $27.5$ ${\mathrm {GeV/}}\mathit c$
$1115.690$ $\pm0.008$ $\pm0.006$ 18k 1
1994
SPEC ${{\mathit p}}{{\mathit p}}$ $27.5$ ${\mathrm {GeV/}}\mathit c$
• • • We do not use the following data for averages, fits, limits, etc. • • •
$1115.59$ $\pm0.08$ 935
1972
HEBC
$1115.39$ $\pm0.12$ 195
1967
EMUL
$1115.6$ $\pm0.4$
1966
HBC
$1115.65$ $\pm0.07$ 488 2
1965
HBC
$1115.44$ $\pm0.12$ 3
1963
RVUE
1 We assume $\mathit CPT$ invariance: this is the ${{\overline{\mathit \Lambda}}}$ mass as measured by HARTOUNI 1994 . See below for the fractional mass difference, testing $\mathit CPT$.
2 The SCHMIDT 1965 masses have been reevaluated using our April 1973 proton and ${{\mathit K}^{\pm}}$ and ${{\mathit \pi}^{\pm}}$ masses. P. Schmidt, private communication (1974).
3 The mass has been raised 35 keV to take into account a 46 keV increase in the proton mass and an 11 keV decrease in the ${{\mathit \pi}^{\pm}}$ mass (note added Reviews of Modern Physics 39 1 (1967)).
References:
HARTOUNI 1994
PRL 72 1322 Precise Measurement of the ${{\mathit \Lambda}^{0}}$ and ${{\overline{\mathit \Lambda}}^{0}}$ Masses and a Test of $\mathit CPT$ Invariance
HYMAN 1972
PR D5 1063 Measurement of ${{\mathit \Lambda}^{0}}$ Mass
MAYEUR 1967
U.Libr.Brux.Bul. 32 A Determination of the Mass of the ${{\mathit \Lambda}}$ Hyperon
LONDON 1966
PR 143 1034 ${{\mathit K}^{-}}{{\mathit p}}$ Interaction at 2.24 BeV
SCHMIDT 1965
PR 140 B1328 Precise Hyperon Masses
BHOWMIK 1963
NC 28 1494 The $\mathit Q_{{{\mathit \Lambda}}}$ $−$ Value for Hyperfragment Binding Energies
| 2021-03-03T09:39:17 |
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https://pos.sissa.it/297/181/
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Volume 297 - XXV International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS2017) - WG4 Hadronic and Electroweak Observables
Framework for evolution in double parton scattering
M. Buffing
Full text: pdf
Pre-published on: 2017 September 30
Published on: 2018 January 16
Abstract
Double parton scattering (DPS) describes two colliding hadrons having interactions in the form of two hard processes, each initiated by a separate pair of partons. Just as for single parton scattering, the resummation of soft gluon exchange gives rise to a soft function, which is a necessary ingredient for obtaining rapidity evolution equations. For various regions of phase space, we derive the rapidity evolution and the scale evolution of double transverse momentum dependent parton distribution functions (DTMDs) as well as of the $p_{T}$-resummed cross section for double Drell-Yan like processes. This contributes to a framework that can be used for phenomenological DPS studies including resummation.
DOI: https://doi.org/10.22323/1.297.0181
Open Access
Copyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
| 2018-07-19T07:46:11 |
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|
https://pdglive.lbl.gov/ParticleGroup.action?sumtab
|
LIGHT UNFLAVORED
($\mathit S$ = $\mathit C$ = $\mathit B$ = 0)
STRANGE
($\mathit S$ = $\pm1$, $\mathit C$ = $\mathit B$ = 0)
CHARMED, STRANGE
($\mathit C$ = $\pm1$, $\mathit S$ = $\pm1$)
(including possibly non- ${\mathit {\mathit q}}$ ${\mathit {\overline{\mathit q}}}$ states)
${\mathit {\mathit c}}$ ${\mathit {\overline{\mathit c}}}$
(including possibly non- ${\mathit {\mathit q}}$ ${\mathit {\overline{\mathit q}}}$ states)
IG(JPC) • ${{\mathit \pi}^{\pm}}$ $1^-(0^{-})$ • ${{\mathit \pi}^{0}}$ $1^-(0^{- +})$ • ${{\mathit \eta}}$ $0^+(0^{- +})$ • ${{\mathit f}_{{0}}{(500)}}$ aka ${{\mathit \sigma}}$; was ${{\mathit f}_{{0}}{(600)}}$ $0^+(0^{+ +})$ • ${{\mathit \rho}{(770)}}$ $1^+(1^{- -})$ • ${{\mathit \omega}{(782)}}$ $0^-(1^{- -})$ • ${{\mathit \eta}^{\,'}{(958)}}$ $0^+(0^{- +})$ • ${{\mathit f}_{{0}}{(980)}}$ $0^+(0^{+ +})$ • ${{\mathit a}_{{0}}{(980)}}$ $1^-(0^{+ +})$ • ${{\mathit \phi}{(1020)}}$ $0^-(1^{- -})$ • ${{\mathit h}_{{1}}{(1170)}}$ $0^-(1^{+ -})$ • ${{\mathit b}_{{1}}{(1235)}}$ $1^+(1^{+ -})$ • ${{\mathit a}_{{1}}{(1260)}}$ $1^-(1^{+ +})$ • ${{\mathit f}_{{2}}{(1270)}}$ $0^+(2^{+ +})$ • ${{\mathit f}_{{1}}{(1285)}}$ $0^+(1^{+ +})$ • ${{\mathit \eta}{(1295)}}$ $0^+(0^{- +})$ • ${{\mathit \pi}{(1300)}}$ $1^-(0^{- +})$ • ${{\mathit a}_{{2}}{(1320)}}$ $1^-(2^{+ +})$ • ${{\mathit f}_{{0}}{(1370)}}$ $0^+(0^{+ +})$ • ${{\mathit \pi}_{{1}}{(1400)}}$ $1^-(1^{- +})$ • ${{\mathit \eta}{(1405)}}$ $0^+(0^{- +})$ • ${{\mathit h}_{{1}}{(1415)}}$ was ${{\mathit h}_{{1}}{(1380)}}$ $0^-(1^{+ -})$ • ${{\mathit f}_{{1}}{(1420)}}$ $0^+(1^{+ +})$ • ${{\mathit \omega}{(1420)}}$ $0^-(1^{- -})$ ${{\mathit f}_{{2}}{(1430)}}$ $0^+(2^{+ +})$ • ${{\mathit a}_{{0}}{(1450)}}$ $1^-(0^{+ +})$ • ${{\mathit \rho}{(1450)}}$ $1^+(1^{- -})$ • ${{\mathit \eta}{(1475)}}$ $0^+(0^{- +})$ • ${{\mathit f}_{{0}}{(1500)}}$ $0^+(0^{+ +})$ ${{\mathit f}_{{1}}{(1510)}}$ $0^+(1^{+ +})$ • ${{\mathit f}_{{2}}^{\,'}{(1525)}}$ $0^+(2^{+ +})$ ${{\mathit f}_{{2}}{(1565)}}$ $0^+(2^{+ +})$ ${{\mathit \rho}{(1570)}}$ $1^+(1^{- -})$ ${{\mathit h}_{{1}}{(1595)}}$ $0^-(1^{+ -})$ • ${{\mathit \pi}_{{1}}{(1600)}}$ $1^-(1^{- +})$ • ${{\mathit a}_{{1}}{(1640)}}$ $1^-(1^{+ +})$ ${{\mathit f}_{{2}}{(1640)}}$ $0^+(2^{+ +})$ • ${{\mathit \eta}_{{2}}{(1645)}}$ $0^+(2^{- +})$ • ${{\mathit \omega}{(1650)}}$ $0^-(1^{- -})$ • ${{\mathit \omega}_{{3}}{(1670)}}$ $0^-(3^{- -})$ • ${{\mathit \pi}_{{2}}{(1670)}}$ $1^-(2^{- +})$ • ${{\mathit \phi}{(1680)}}$ $0^-(1^{- -})$ • ${{\mathit \rho}_{{3}}{(1690)}}$ $1^+(3^{- -})$
IG(JPC) • ${{\mathit \rho}{(1700)}}$ $1^+(1^{- -})$ • ${{\mathit a}_{{2}}{(1700)}}$ $1^-(2^{+ +})$ • ${{\mathit f}_{{0}}{(1710)}}$ $0^+(0^{+ +})$ ${{\mathit X}{(1750)}}$ $?^-(1^{- -})$ ${{\mathit \eta}{(1760)}}$ $0^+(0^{- +})$ • ${{\mathit \pi}{(1800)}}$ $1^-(0^{- +})$ ${{\mathit f}_{{2}}{(1810)}}$ $0^+(2^{+ +})$ ${{\mathit X}{(1835)}}$ $?^?(0^{- +})$ • ${{\mathit \phi}_{{3}}{(1850)}}$ $0^-(3^{- -})$ • ${{\mathit \eta}_{{2}}{(1870)}}$ $0^+(2^{- +})$ • ${{\mathit \pi}_{{2}}{(1880)}}$ $1^-(2^{- +})$ ${{\mathit \rho}{(1900)}}$ $1^+(1^{- -})$ ${{\mathit f}_{{2}}{(1910)}}$ $0^+(2^{+ +})$ ${{\mathit a}_{{0}}{(1950)}}$ $1^-(0^{+ +})$ • ${{\mathit f}_{{2}}{(1950)}}$ $0^+(2^{+ +})$ • ${{\mathit a}_{{4}}{(1970)}}$ was ${{\mathit a}_{{4}}{(2040)}}$ $1^-(4^{+ +})$ ${{\mathit \rho}_{{3}}{(1990)}}$ $1^+(3^{- -})$ ${{\mathit \pi}_{{2}}{(2005)}}$ $1^-(2^{- +})$ • ${{\mathit f}_{{2}}{(2010)}}$ $0^+(2^{+ +})$ ${{\mathit f}_{{0}}{(2020)}}$ $0^+(0^{+ +})$ • ${{\mathit f}_{{4}}{(2050)}}$ $0^+(4^{+ +})$ ${{\mathit \pi}_{{2}}{(2100)}}$ $1^-(2^{- +})$ ${{\mathit f}_{{0}}{(2100)}}$ $0^+(0^{+ +})$ ${{\mathit f}_{{2}}{(2150)}}$ $0^+(2^{+ +})$ ${{\mathit \rho}{(2150)}}$ $1^+(1^{- -})$ • ${{\mathit \phi}{(2170)}}$ $0^-(1^{- -})$ ${{\mathit f}_{{0}}{(2200)}}$ $0^+(0^{+ +})$ ${{\mathit f}_{{J}}{(2220)}}$ $0^+(2{}^{++}~$ or $~4^{+ +})$ ${{\mathit \eta}{(2225)}}$ $0^+(0^{- +})$ ${{\mathit \rho}_{{3}}{(2250)}}$ $1^+(3^{- -})$ • ${{\mathit f}_{{2}}{(2300)}}$ $0^+(2^{+ +})$ ${{\mathit f}_{{4}}{(2300)}}$ $0^+(4^{+ +})$ ${{\mathit f}_{{0}}{(2330)}}$ $0^+(0^{+ +})$ • ${{\mathit f}_{{2}}{(2340)}}$ $0^+(2^{+ +})$ ${{\mathit \rho}_{{5}}{(2350)}}$ $1^+(5^{- -})$ ${{\mathit X}{(2370)}}$ $?^?(?^{? ?})$ ${{\mathit f}_{{6}}{(2510)}}$ $0^+(6^{+ +})$ OTHER MESONS Further States
I(JP) • ${{\mathit K}^{\pm}}$ $1/2(0^{-})$ • ${{\mathit K}^{0}}$ $1/2(0^{-})$ • ${{\mathit K}_S^0}$ $1/2(0^{-})$ • ${{\mathit K}_L^0}$ $1/2(0^{-})$ • ${{\mathit K}_{{0}}^{*}{(700)}}$ aka ${{\mathit \kappa}}$; was ${{\mathit K}_{{0}}^{*}{(800)}}$ $1/2(0^{+})$ • ${{\mathit K}^{*}{(892)}}$ $1/2(1^{-})$ • ${{\mathit K}_{{1}}{(1270)}}$ $1/2(1^{+})$ • ${{\mathit K}_{{1}}{(1400)}}$ $1/2(1^{+})$ • ${{\mathit K}^{*}{(1410)}}$ $1/2(1^{-})$ • ${{\mathit K}_{{0}}^{*}{(1430)}}$ $1/2(0^{+})$ • ${{\mathit K}_{{2}}^{*}{(1430)}}$ $1/2(2^{+})$ • ${{\mathit K}{(1460)}}$ $1/2(0^{-})$ ${{\mathit K}_{{2}}{(1580)}}$ $1/2(2^{-})$ ${{\mathit K}{(1630)}}$ $1/2(?^{?})$ • ${{\mathit K}_{{1}}{(1650)}}$ $1/2(1^{+})$ • ${{\mathit K}^{*}{(1680)}}$ $1/2(1^{-})$ • ${{\mathit K}_{{2}}{(1770)}}$ $1/2(2^{-})$ • ${{\mathit K}_{{3}}^{*}{(1780)}}$ $1/2(3^{-})$ • ${{\mathit K}_{{2}}{(1820)}}$ $1/2(2^{-})$ ${{\mathit K}{(1830)}}$ $1/2(0^{-})$ ${{\mathit K}_{{0}}^{*}{(1950)}}$ $1/2(0^{+})$ • ${{\mathit K}_{{2}}^{*}{(1980)}}$ $1/2(2^{+})$ • ${{\mathit K}_{{4}}^{*}{(2045)}}$ $1/2(4^{+})$ ${{\mathit K}_{{2}}{(2250)}}$ $1/2(2^{-})$ ${{\mathit K}_{{3}}{(2320)}}$ $1/2(3^{+})$ ${{\mathit K}_{{5}}^{*}{(2380)}}$ $1/2(5^{-})$ ${{\mathit K}_{{4}}{(2500)}}$ $1/2(4^{-})$ ${{\mathit K}{(3100)}}$ $?^?(?^{? ?})$ CHARMED($\mathit C$ = $\pm1$) • ${{\mathit D}^{\pm}}$ $1/2(0^{-})$ • ${{\mathit D}^{0}}$ $1/2(0^{-})$ • ${{\mathit D}^{*}{(2007)}^{0}}$ $1/2(1^{-})$ • ${{\mathit D}^{*}{(2010)}^{\pm}}$ $1/2(1^{-})$ • ${{\mathit D}_{{0}}^{*}{(2300)}}$ was ${{\mathit D}_{{0}}^{*}{(2400)}}$ $1/2(0^{+})$ • ${{\mathit D}_{{1}}{(2420)}}$ $1/2(1^{+})$ • ${{\mathit D}_{{1}}{(2430)}^{0}}$ $1/2(1^{+})$ • ${{\mathit D}_{{2}}^{*}{(2460)}}$ $1/2(2^{+})$ ${{\mathit D}_{{0}}{(2550)}^{0}}$ $1/2(0^{-})$ ${{\mathit D}_{{1}}^{*}{(2600)}^{0}}$ was ${{\mathit D}_{{J}}^{*}{(2600)}}$ $1/2(1^{-})$ ${{\mathit D}^{*}{(2640)}^{\pm}}$ $1/2(?^{?})$ ${{\mathit D}_{{2}}{(2740)}^{0}}$ was ${{\mathit D}{(2740)}^{0}}$ $1/2(2^{-})$ • ${{\mathit D}_{{3}}^{*}{(2750)}}$ $1/2(3^{-})$ ${{\mathit D}_{{1}}^{*}{(2760)}^{0}}$ $1/2(1^{-})$ ${{\mathit D}{(3000)}^{0}}$ $1/2(?^{?})$
I(JP) • ${{\mathit D}_{{s}}^{\pm}}$ $0(0^{-})$ • ${{\mathit D}_{{s}}^{*\pm}}$ $0(?^{?})$ • ${{\mathit D}_{{s0}}^{*}{(2317)}^{\pm}}$ $0(0^{+})$ • ${{\mathit D}_{{s1}}{(2460)}^{\pm}}$ $0(1^{+})$ • ${{\mathit D}_{{s1}}{(2536)}^{\pm}}$ $0(1^{+})$ • ${{\mathit D}_{{s2}}^{*}{(2573)}}$ $0(2^{+})$ ${{\mathit D}_{{s0}}{(2590)}^{+}}$ $0(0^{-})$ • ${{\mathit D}_{{s1}}^{*}{(2700)}^{\pm}}$ $0(1^{-})$ ${{\mathit D}_{{s1}}^{*}{(2860)}^{\pm}}$ $0(1^{-})$ • ${{\mathit D}_{{s3}}^{*}{(2860)}^{\pm}}$ $0(3^{-})$ ${{\mathit X}_{{0}}{(2900)}}$ $?(0^{+})$ ${{\mathit X}_{{1}}{(2900)}}$ $?(1^{-})$ ${{\mathit D}_{{sJ}}{(3040)}^{\pm}}$ $0(?^{?})$ BOTTOM($\mathit B$ = $\pm1$) • ${{\mathit B}^{\pm}}$ $1/2(0^{-})$ • ${{\mathit B}^{0}}$ $1/2(0^{-})$ • ${{\mathit B}^{\pm}}$ /${{\mathit B}^{0}}$ ADMIXTURE • ${{\mathit B}^{\pm}}$ /${{\mathit B}^{0}}$ /${{\mathit B}_{{s}}^{0}}$ /${{\mathit b}}$ -baryon ADMIXTURE $\mathit V_{cb}$ and $\mathit V_{ub}$ CKM Matrix Elements • ${{\mathit B}^{*}}$ $1/2(1^{-})$ • ${{\mathit B}_{{1}}{(5721)}}$ $1/2(1^{+})$ ${{\mathit B}_{{J}}^{*}{(5732)}}$ aka ${{\mathit B}^{**}}$ $?(?^{?})$ • ${{\mathit B}_{{2}}^{*}{(5747)}}$ $1/2(2^{+})$ ${{\mathit B}_{{J}}{(5840)}}$ $1/2(?^{?})$ • ${{\mathit B}_{{J}}{(5970)}}$ $1/2(?^{?})$ BOTTOM, STRANGE($\mathit B$ = $\pm1$, $\mathit S$ = $\mp{}$1) • ${{\mathit B}_{{s}}^{0}}$ $0(0^{-})$ • ${{\mathit B}_{{s}}^{*}}$ $0(1^{-})$ ${{\mathit X}{(5568)}^{\pm}}$ $?(?^{?})$ • ${{\mathit B}_{{s1}}{(5830)}^{0}}$ $0(1^{+})$ • ${{\mathit B}_{{s2}}^{*}{(5840)}^{0}}$ $0(2^{+})$ ${{\mathit B}_{{sJ}}^{*}{(5850)}}$ $?(?^{?})$ ${{\mathit B}_{{sJ}}{(6063)}^{0}}$ $0(?^{?})$ ${{\mathit B}_{{sJ}}{(6114)}^{0}}$ $0(?^{?})$ BOTTOM, CHARMED($\mathit B$ = $\mathit C$ = $\pm{}$1) • ${{\mathit B}_{{c}}^{+}}$ $0(0^{-})$ • ${{\mathit B}_{{c}}{(2S)}^{\pm}}$ $0(0^{-})$
IG(JPC) • ${{\mathit \eta}_{{c}}{(1S)}}$ $0^+(0^{- +})$ • ${{\mathit J / \psi}{(1S)}}$ $0^-(1^{- -})$ • ${{\mathit \chi}_{{c0}}{(1P)}}$ $0^+(0^{+ +})$ • ${{\mathit \chi}_{{c1}}{(1P)}}$ $0^+(1^{+ +})$ • ${{\mathit h}_{{c}}{(1P)}}$ $0^-(1^{+ -})$ • ${{\mathit \chi}_{{c2}}{(1P)}}$ $0^+(2^{+ +})$ • ${{\mathit \eta}_{{c}}{(2S)}}$ $0^+(0^{- +})$ • ${{\mathit \psi}{(2S)}}$ $0^-(1^{- -})$ • ${{\mathit \psi}{(3770)}}$ $0^-(1^{- -})$ • ${{\mathit \psi}_{{2}}{(3823)}}$ was ${{\mathit \psi}{(3823)}}$, ${{\mathit X}{(3823)}}$ $0^-(2^{- -})$ • ${{\mathit \psi}_{{3}}{(3842)}}$ $0^-(3^{- -})$ ${{\mathit \chi}_{{c0}}{(3860)}}$ $0^+(0^{+ +})$ • ${{\mathit \chi}_{{c1}}{(3872)}}$ aka ${{\mathit X}{(3872)}}$ $0^+(1^{+ +})$ • ${{\mathit Z}_{{c}}{(3900)}}$ was ${{\mathit X}{(3900)}}$ $1^+(1^{+ -})$ • ${{\mathit \chi}_{{c0}}{(3915)}}$ was ${{\mathit X}{(3915)}}$ $0^+(0^{+ +})$ • ${{\mathit \chi}_{{c2}}{(3930)}}$ $0^+(2^{+ +})$ ${{\mathit X}{(3940)}}$ $?^?(?^{? ?})$ • ${{\mathit X}{(4020)}^{\pm}}$ $1^+(?^{? -})$ • ${{\mathit \psi}{(4040)}}$ $0^-(1^{- -})$ ${{\mathit X}{(4050)}^{\pm}}$ $1^-(?^{? +})$ ${{\mathit X}{(4055)}^{\pm}}$ $1^+(?^{? -})$ ${{\mathit X}{(4100)}^{\pm}}$ $1^-(?^{? ?})$ • ${{\mathit \chi}_{{c1}}{(4140)}}$ was ${{\mathit X}{(4140)}}$ $0^+(1^{+ +})$ • ${{\mathit \psi}{(4160)}}$ $0^-(1^{- -})$ ${{\mathit X}{(4160)}}$ $?^?(?^{? ?})$ ${{\mathit Z}_{{c}}{(4200)}}$ was ${{\mathit X}{(4200)}^{\pm}}$ $1^+(1^{+ -})$ • ${{\mathit \psi}{(4230)}}$ aka ${{\mathit Y}{(4230)}}$; was ${{\mathit \psi}{(4260)}}$ $0^-(1^{- -})$ ${{\mathit R}_{{c0}}{(4240)}}$ was ${{\mathit X}{(4240)}^{\pm}}$ $1^+(0^{- -})$ ${{\mathit X}{(4250)}^{\pm}}$ $1^-(?^{? +})$ • ${{\mathit \chi}_{{c1}}{(4274)}}$ was ${{\mathit X}{(4274)}}$ $0^+(1^{+ +})$ ${{\mathit X}{(4350)}}$ $0^+(?^{? +})$ • ${{\mathit \psi}{(4360)}}$ aka ${{\mathit Y}{(4360)}}$; was ${{\mathit X}{(4360)}}$ $0^-(1^{- -})$ • ${{\mathit \psi}{(4415)}}$ $0^-(1^{- -})$ • ${{\mathit Z}_{{c}}{(4430)}}$ was ${{\mathit X}{(4430)}^{\pm}}$ $1^+(1^{+ -})$ ${{\mathit \chi}_{{c0}}{(4500)}}$ was ${{\mathit X}{(4500)}}$ $0^+(0^{+ +})$ ${{\mathit X}{(4630)}}$ $0^+(?^{? +})$ • ${{\mathit \psi}{(4660)}}$ aka ${{\mathit Y}{(4660)}}$; was ${{\mathit X}{(4660)}}$ $0^-(1^{- -})$ ${{\mathit \chi}_{{c1}}{(4685)}}$ $0^+(1^{+ +})$ ${{\mathit \chi}_{{c0}}{(4700)}}$ was ${{\mathit X}{(4700)}}$ $0^+(0^{+ +})$ ${\mathit {\mathit b}}$ ${\mathit {\overline{\mathit b}}}$(including possibly non- ${\mathit {\mathit q}}$ ${\mathit {\overline{\mathit q}}}$ states) • ${{\mathit \eta}_{{b}}{(1S)}}$ $0^+(0^{- +})$ • ${{\mathit \Upsilon}{(1S)}}$ $0^-(1^{- -})$ • ${{\mathit \chi}_{{b0}}{(1P)}}$ $0^+(0^{+ +})$ • ${{\mathit \chi}_{{b1}}{(1P)}}$ $0^+(1^{+ +})$ • ${{\mathit h}_{{b}}{(1P)}}$ $0^-(1^{+ -})$ • ${{\mathit \chi}_{{b2}}{(1P)}}$ $0^+(2^{+ +})$ ${{\mathit \eta}_{{b}}{(2S)}}$ $0^+(0^{- +})$ • ${{\mathit \Upsilon}{(2S)}}$ $0^-(1^{- -})$ • ${{\mathit \Upsilon}_{{2}}{(1D)}}$ was ${{\mathit \Upsilon}{(1D)}}$ $0^-(2^{- -})$ • ${{\mathit \chi}_{{b0}}{(2P)}}$ $0^+(0^{+ +})$ • ${{\mathit \chi}_{{b1}}{(2P)}}$ $0^+(1^{+ +})$ • ${{\mathit h}_{{b}}{(2P)}}$ $0^-(1^{+ -})$ • ${{\mathit \chi}_{{b2}}{(2P)}}$ $0^+(2^{+ +})$ • ${{\mathit \Upsilon}{(3S)}}$ $0^-(1^{- -})$ • ${{\mathit \chi}_{{b1}}{(3P)}}$ $0^+(1^{+ +})$ • ${{\mathit \chi}_{{b2}}{(3P)}}$ $0^+(2^{+ +})$ • ${{\mathit \Upsilon}{(4S)}}$ aka ${{\mathit \Upsilon}{(10580)}}$ $0^-(1^{- -})$ • ${{\mathit Z}_{{b}}{(10610)}}$ was ${{\mathit X}{(10610)}}$ $1^+(1^{+ -})$ • ${{\mathit Z}_{{b}}{(10650)}}$ was ${{\mathit X}{(10650)}^{\pm}}$ $1^+(1^{+ -})$ ${{\mathit \Upsilon}{(10753)}}$ $?^?(1^{- -})$ • ${{\mathit \Upsilon}{(10860)}}$ $0^-(1^{- -})$ • ${{\mathit \Upsilon}{(11020)}}$ $0^-(1^{- -})$
• Indicates established particles.
| 2022-12-07T20:46:22 |
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|
http://dergipark.gov.tr/else/issue/29303/313718
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## MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM
#### Mehmet ERTAŞ [1] , Mustafa KESKİN [2]
##### 93 117
Magnetic nanowire systems have attracted considerable attention not only because of their academic interest, but also due to the technological applications; in particular, in the areas of magnetic recording media, spin electronics, optics, sensors and thermo electronics devices. On the other hand, in the last two decades, mixed spin Ising systems have been intensively studied. The reasons are as follows: (i) the systems have less translational symmetry than their single spin counterparts. (ii) The study of these systems can be relevant for understanding the bimetallic molecular system-based magnetic materials. (iii) Mixed spin Ising systems provide good models to investigate the ferromagnetic materials. In this work, by utilizing the framework of the effective field theory with correlation, magnetic properties of mixed spin (1, 2) hexagonal Ising nanowire system is studied in detail. The effects of Hamiltonian parameters on hysteresis and compensation behaviors are also discussed extensively. Finally, the results are compared with some experimental and theoretical works and found in a qualitatively good agreement.
Mixed spin (1, 2) hexagonal Ising nanowire, the effective field theory, hysteresis and compensation
Konular JA53EG74EV Makaleler Yazar: Mehmet ERTAŞ Yazar: Mustafa KESKİN
Bibtex @ { else313718, journal = {Electronic Letters on Science\&Engineering}, issn = {1305-8614}, address = {Bozok Üniversitesi}, year = {2016}, volume = {12}, pages = {22 - 22}, doi = {}, title = {MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM}, key = {cite}, author = {KESKİN, Mustafa and ERTAŞ, Mehmet} } APA ERTAŞ, M , KESKİN, M . (2016). MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM. Electronic Letters on Science&Engineering, 12 (2), 22-22. Retrieved from http://dergipark.gov.tr/else/issue/29303/313718 MLA ERTAŞ, M , KESKİN, M . "MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM". Electronic Letters on Science&Engineering 12 (2016): 22-22 Chicago ERTAŞ, M , KESKİN, M . "MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM". Electronic Letters on Science&Engineering 12 (2016): 22-22 RIS TY - JOUR T1 - MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM AU - Mehmet ERTAŞ , Mustafa KESKİN Y1 - 2016 PY - 2016 N1 - DO - T2 - Electronic Letters on Science&Engineering JF - Journal JO - JOR SP - 22 EP - 22 VL - 12 IS - 2 SN - 1305-8614- M3 - UR - Y2 - 2018 ER - EndNote %0 Electronic Letters on Science&Engineering MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM %A Mehmet ERTAŞ , Mustafa KESKİN %T MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM %D 2016 %J Electronic Letters on Science&Engineering %P 1305-8614- %V 12 %N 2 %R %U ISNAD ERTAŞ, Mehmet , KESKİN, Mustafa . "MAGNETIC PROPERTIES OF MIXED SPIN (1, 2) HEXAGONAL ISING NANOWIRE SYSTEM". Electronic Letters on Science&Engineering 12 / 2 (Ağustos 2016): 22-22.
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http://www.scstatehouse.gov/sess118_2009-2010/sj10/20100309.htm
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South Carolina General Assembly
118th Session, 2009-2010
Journal of the Senate
Tuesday, March 9, 2010
(Statewide Session)
Indicates Matter Stricken
Indicates New Matter
The Senate assembled at 12:00 Noon, the hour to which it stood adjourned, and was called to order by the PRESIDENT.
A quorum being present, the proceedings were opened with a devotion by the Chaplain as follows:
" 'Meaningless! Meaningless!' says the Teacher. 'Utterly meaningless! Everything is meaningless.' " (Ecclesiastes 1:2)
Loving and Gracious God, we might agree that apart from You life might well be thought of by some people as "meaningless." Indeed, we cringe to think of those who really believe that life holds no meaning. How reassuring it is to be on the other side of the ledger: to know that You invite us to trust in You, to feel Your presence and power, to hold fast to Your hopeful promises for the future. O Lord, fill these very leaders with Your purpose. Guide these servants of Yours to accomplish great good, never being content with anything less than worthy and noble results. We pray all of this in Your loving name, dear Lord.
Amen.
The PRESIDENT called for Petitions, Memorials, Presentments of Grand Juries and such like papers.
Doctor of the Day
Senator COURSON introduced Dr. Bill Gerald of Columbia, S.C., Doctor of the Day.
Leave of Absence
On motion of Senator FAIR, at 12:05 P.M., Senator SHOOPMAN was granted a leave of absence for this week.
Leave of Absence
At 12:40 P.M., Senator SHEHEEN requested a leave of absence from 1:00 - 3:00 P.M.
Leave of Absence
On motion of Senator THOMAS, at 4:15 P.M., Senator HAYES was granted a leave of absence for the balance of the day.
S. 642 (Word version) Sen. Knotts
S. 903 (Word version) Sens. Anderson, Larry Martin
S. 1008 (Word version) Sen. Campsen
S. 1057 (Word version) Sen. Courson
S. 1075 (Word version) Sen. Campsen
S. 1167 (Word version) Sen. Campsen
S. 1185 (Word version) Sen. Campsen
S. 1188 (Word version) Sen. Campsen
INTRODUCTION OF BILLS AND RESOLUTIONS
The following were introduced:
S. 1258 (Word version) -- Senator Pinckney: A SENATE RESOLUTION TO EXPRESS THE PROFOUND SORROW OF THE MEMBERS OF THE SOUTH CAROLINA SENATE UPON THE PASSING OF THE HONORABLE ALBERT LLOYD KLECKLEY, SR. OF OKATIE AND TO EXTEND THE DEEPEST SYMPATHY TO HIS FAMILY AND MANY FRIENDS.
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S. 1259 (Word version) -- Senator Cromer: A SENATE RESOLUTION TO RECOGNIZE AND EXPRESS THE APPRECIATION OF THE MEMBERS OF THE SENATE TO RAYMOND K. WICKER, ESQUIRE OF THE NEWBERRY COUNTY BAR ON THE OCCASION OF HIS RETIREMENT, AND TO COMMEND HIM FOR FIFTY YEARS OF DEDICATED AND DISTINGUISHED SERVICE AS A MEMBER OF THE SOUTH CAROLINA BAR, AND FOR HIS OUTSTANDING RECORD OF ACHIEVEMENT WHILE SERVING HIS NATION, STATE, COUNTY, CITY, AND CHURCH.
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S. 1260 (Word version) -- Senator Alexander: A CONCURRENT RESOLUTION TO CONGRATULATE MR. BENNIE CUNNINGHAM UPON RECEIVING THE JOSEPH R. JENKINS AWARD BY THE GREENVILLE ALUMNI CHAPTER OF THE KAPPA ALPHA PSI FRATERNITY.
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The Concurrent Resolution was adopted, ordered sent to the House.
S. 1261 (Word version) -- Senator Cromer: A BILL TO AMEND ARTICLE 5, CHAPTER 3, TITLE 50, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE CUTTING OF TIMBER ON LANDS HELD BY THE DEPARTMENT OF NATURAL RESOURCES, SO AS TO MAKE TECHNICAL CORRECTIONS; TO DELETE OBSOLETE REFERENCES; TO REQUIRE THE DEPARTMENT TO COORDINATE THE CUTTING AND SALE OF SUCH TIMBER WITH THE STATE FORESTER, RATHER THAN TO SUBMIT THE MATTER TO THE STATE FORESTER FOR APPROVAL; TO PROVIDE THAT LAND OWNED BY THE DEPARTMENT THAT WAS PREVIOUSLY USED FOR AGRICULTURE OR MANAGED FOREST LAND MUST BE MANAGED TO PROVIDE OPTIMUM FISH AND WILDLIFE HABITAT AND TIMBER PRODUCTION; TO REVISE PROCEDURES FOR ADVERTISING FOR BIDS ON THE TIMBER; TO PROVIDE PROCEDURES FOR THE HARVEST AND SALE OF TIMBER IF AN EMERGENCY OR NATURAL DISASTER OCCURS NECESSITATING IMMEDIATE HARVESTING OF TIMBER; TO AUTHORIZE THE DIRECTOR OF THE DEPARTMENT, RATHER THAN THE BOARD, TO EXECUTE DEEDS AND CONTRACTS REQUIRED IN CARRYING OUT THIS ARTICLE; AND TO PROVIDE THAT, UNLESS OTHERWISE PROVIDED FOR, THE PROCEEDS OF THESE TIMBER SALES MUST CONTINUE TO BE CREDITED TO THE FISH AND WILDLIFE PROTECTION FUND.
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Read the first time and referred to the Committee on Fish, Game and Forestry.
H. 4093 (Word version) -- Reps. Loftis, Mitchell, H. B. Brown, Bedingfield, Anthony, G. A. Brown, Crawford, Dillard, Harvin, Hiott, Knight, Lowe, J. R. Smith, Toole, D. C. Moss, Sellers, Brady, Funderburk, Hodges, Horne, Gunn, Bowers, Hutto and Stavrinakis: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING CHAPTER 60 TO TITLE 48 TO ENACT THE "SOUTH CAROLINA MANUFACTURER RESPONSIBILITY AND CONSUMER CONVENIENCE INFORMATION TECHNOLOGY EQUIPMENT COLLECTION AND RECOVERY ACT"; TO PROVIDE CERTAIN FINDINGS BY THE GENERAL ASSEMBLY RELATED TO THE ACT; TO PROVIDE CERTAIN DEFINITIONS RELATED TO THE ACT; TO REQUIRE A MANUFACTURER OF CERTAIN COMPUTING, DISPLAY, OR PRINTING EQUIPMENT TO OFFER A RECOVERY PROGRAM FOR THE COLLECTION OF EQUIPMENT FROM A CONSUMER IN A MANNER CONVENIENT TO THE CONSUMER; TO REQUIRE A MANUFACTURER TO DOCUMENT ITS COMPLIANCE WITH THIS CHAPTER IN AN ANNUAL REPORT TO THE DEPARTMENT; TO LIMIT THE LIABILITY OF A MANUFACTURER FOR DAMAGE SUSTAINED BY A CONSUMER FROM INFORMATION CONTAINED ON EQUIPMENT RETURNED BY THE CONSUMER TO A MANUFACTURER THROUGH THE MANUFACTURER'S RECOVERY PROGRAM; TO REQUIRE A RETAILER TO SELL ONLY EQUIPMENT MANUFACTURED IN COMPLIANCE WITH THIS CHAPTER; TO LIMIT THE LIABILITY OF A RETAILER FOR DAMAGE SUSTAINED BY A CONSUMER FROM INFORMATION CONTAINED ON EQUIPMENT SOLD BY THE RETAILER TO A CONSUMER AND RETURNED TO THE MANUFACTURER OF THE EQUIPMENT THROUGH THE MANUFACTURER'S RECOVERY PROGRAM; TO REQUIRE A MANUFACTURER TO EDUCATE CONSUMERS ABOUT THE MANUFACTURER'S RECOVERY PROGRAM; TO REQUIRE THE DEPARTMENT TO EDUCATE CONSUMERS ABOUT ALL RECOVERY PROGRAMS AVAILABLE IN THIS STATE; TO ENABLE THE DEPARTMENT TO AUDIT A MANUFACTURER TO DETERMINE THE MANUFACTURER'S COMPLIANCE WITH THIS CHAPTER; TO PROVIDE THAT FINANCIAL AND PROPRIETARY INFORMATION SUBMITTED TO THE DEPARTMENT BY A MANUFACTURER OR RETAILER PURSUANT TO THIS CHAPTER IS EXEMPT FROM PUBLIC DISCLOSURE; TO REQUIRE THE DEPARTMENT TO REPORT ANNUALLY INFORMATION PROVIDED BY A MANUFACTURER OR A RETAILER TO THE GENERAL ASSEMBLY; TO REQUIRE THE DEPARTMENT TO DEVELOP STANDARDS FOR RECOVERY PROGRAMS, REPORTING REQUIREMENTS, AND RECOVERER CERTIFICATION THAT COMPLY WITH THE ELECTRONICS RECYCLING OPERATING PRACTICES OF THE INSTITUTE OF SCRAP RECYCLING INDUSTRIES; AND TO PROVIDE THAT THE DEPARTMENT MAY PROMULGATE RULES AND REGULATIONS NEEDED TO IMPLEMENT THIS CHAPTER'S PROVISIONS.
Read the first time and referred to the Committee on Agriculture and Natural Resources.
H. 4225 (Word version) -- Reps. Rutherford, McLeod and Weeks: A BILL TO AMEND SECTION 16-3-1400, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO DEFINITIONS FOR PURPOSES OF THE ARTICLE ON THE VICTIM ASSISTANCE PROGRAM, SO AS TO PROVIDE THAT THE TERM "VICTIM SERVICE PROVIDER" DOES NOT INCLUDE MAGISTRATE OR MUNICIPAL JUDGES AND THEIR STAFF.
Read the first time and referred to the Committee on Judiciary.
H. 4248 (Word version) -- Reps. Horne, Allison, Daning, Long, Littlejohn, Wylie, Gunn, Ballentine, Clemmons and Loftis: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING SECTION 59-19-115 SO AS TO REQUIRE A SUBSTITUTE TEACHER HIRED BY A LOCAL SCHOOL DISTRICT TO UNDERGO A CRIMINAL RECORD SEARCH, TO REQUIRE EACH SCHOOL DISTRICT TO DEVELOP A WRITTEN POLICY ON THE CRIMINAL RECORD SEARCH, TO PROVIDE WHAT THE POLICY MUST INCLUDE, AND TO REQUIRE THE SOUTH CAROLINA LAW ENFORCEMENT DIVISION TO PROVIDE TRAINING TO APPROPRIATE SCHOOL DISTRICT PERSONNEL; AND TO AMEND SECTION 23-3-115, RELATING TO FEES FOR CRIMINAL RECORD SEARCHES, SO AS TO FIX THE FEE AT EIGHT DOLLARS FOR CERTAIN SCHOOL DISTRICT EMPLOYEES.
Read the first time and referred to the Committee on Education.
H. 4256 (Word version) -- Reps. Harrison and Weeks: A BILL TO AMEND SECTION 17-30-125, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO INCIDENCES WHEN THE SUPERVISING AGENT OF A LAW ENFORCEMENT AGENCY MAY ORDER CERTAIN PERSONS TO CUT, REROUTE, OR DIVERT TELEPHONE LINES FOR CERTAIN PURPOSES, SO AS TO PROVIDE THAT THE SUPERVISING AGENT OF A LAW ENFORCEMENT AGENCY MAY ISSUE ADMINISTRATIVE SUBPOENA TO A TELEPHONE COMPANY, INTERNET SERVICE PROVIDER, OR ANOTHER COMMUNICATIONS ENTITY WHEN IT RECEIVES INFORMATION THAT INDICATES THAT A PERSON'S LIFE IS THREATENED, A PRISONER MAY ESCAPE, A PERSON IS BEING HELD AS A HOSTAGE, A PERSON MAY RESIST ARREST WHILE USING A WEAPON, OR AN ARMED PERSON MAY COMMIT SUICIDE, AND TO PROVIDE THAT THE GOOD FAITH RELIANCE BY A TELEPHONE COMPANY, INTERNET SERVICE PROVIDER, OR ANOTHER COMMUNICATIONS ENTITY TO PROVIDE INFORMATION SPECIFIED IN AN ADMINISTRATIVE SUBPOENA IS A COMPLETE DEFENSE TO A CIVIL, CRIMINAL, OR ADMINISTRATIVE ACTION ARISING OUT OF THE ORDER OR ADMINISTRATIVE SUBPOENA.
Read the first time and referred to the Committee on Judiciary.
H. 4261 (Word version) -- Reps. Harrison and Weeks: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ADDING SECTION 23-3-75 SO AS TO PROVIDE THAT THE DIRECTOR OF THE SOUTH CAROLINA LAW ENFORCEMENT DIVISION, OR HIS DESIGNEE, MAY ISSUE AN ADMINISTRATIVE SUBPOENA FOR THE PRODUCTION OF RECORDS DURING THE INVESTIGATION OF CERTAIN CRIMINAL CASES THAT INVOLVE FINANCIAL CRIMES.
Read the first time and referred to the Committee on Judiciary.
H. 4434 (Word version) -- Reps. Nanney, Clemmons, Horne and Sellers: A BILL TO AMEND SECTION 7-13-35, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE NOTICE OF ELECTION GIVEN BY THE AUTHORITY CHARGED BY LAW WITH CONDUCTING AN ELECTION, SO AS TO DELETE THE REQUIREMENT THAT THE NOTICE BE PUBLISHED IN A NEWSPAPER AND THAT INSTEAD IT BE POSTED ON THE WEBSITE OF THE STATE ELECTION COMMISSION, AND TO PROVIDE THAT THIS NOTICE BE POSTED FORTY-FIVE DAYS INSTEAD OF SIXTY DAYS BEFORE AN ELECTION.
Read the first time and referred to the Committee on Judiciary.
Read the first time and referred to the Committee on Finance.
H. 4684 (Word version) -- Rep. Anthony: A BILL TO AMEND ACT 848 OF 1946, AS AMENDED, RELATING TO THE CREATION OF THE UNION HOSPITAL DISTRICT, SO AS TO ADD THREE ADVISORY MEMBERS TO THE DISTRICT'S BOARD OF TRUSTEES, AND TO DELETE PROVISIONS MAKING THE UNION COUNTY TREASURER THE BOARD'S TREASURER, PROHIBITING A TRUSTEE FROM RECEIVING COMPENSATION, ALLOWING REIMBURSEMENT TO A TRUSTEE FOR ACTUAL CASH EXPENDITURES MADE BY HIM AS A TRUSTEE, AND CONCERNING A SEAL AND CERTAIN OFFICE PROCEDURES OF THE DISTRICT.
Read the first time and ordered placed on the Local and Uncontested Calendar.
H. 4694 (Word version) -- Reps. Erickson, Herbkersman, Agnew, Alexander, Allen, Allison, Anderson, Anthony, Bales, Ballentine, Bannister, Barfield, Battle, Bedingfield, Bingham, Bowen, Bowers, Brady, Branham, Brantley, G. A. Brown, H. B. Brown, R. L. Brown, Cato, Chalk, Clemmons, Clyburn, Cobb-Hunter, Cole, Cooper, Crawford, Daning, Delleney, Dillard, Duncan, Edge, Forrester, Frye, Funderburk, Gambrell, Gilliard, Govan, Gunn, Haley, Hamilton, Hardwick, Harrell, Harrison, Hart, Harvin, Hayes, Hearn, Hiott, Hodges, Horne, Hosey, Howard, Huggins, Hutto, Jefferson, Jennings, Kelly, Kennedy, King, Kirsh, Knight, Limehouse, Littlejohn, Loftis, Long, Lowe, Lucas, Mack, McEachern, McLeod, Merrill, Miller, Millwood, Mitchell, D. C. Moss, V. S. Moss, Nanney, J. H. Neal, J. M. Neal, Neilson, Norman, Ott, Owens, Parker, Parks, Pinson, E. H. Pitts, M. A. Pitts, Rice, Rutherford, Sandifer, Scott, Sellers, Simrill, Skelton, D. C. Smith, G. M. Smith, G. R. Smith, J. E. Smith, J. R. Smith, Sottile, Spires, Stavrinakis, Stewart, Stringer, Thompson, Toole, Umphlett, Vick, Viers, Weeks, Whipper, White, Whitmire, Williams, Willis, Wylie, A. D. Young and T. R. Young: A CONCURRENT RESOLUTION TO COMMEND THE UNIVERSITY OF SOUTH CAROLINA BEAUFORT FOR ITS MANY YEARS OF SERVICE TO THE STATE OF SOUTH CAROLINA, AND TO HONOR AND CONGRATULATE THE UNIVERSITY OF SOUTH CAROLINA BEAUFORT ON THE OCCASION OF ITS FIFTIETH ANNIVERSARY.
The Concurrent Resolution was adopted, ordered returned to the House.
H. 4699 (Word version) -- Reps. Haley, Ballentine, Bingham, Brantley, Chalk, Erickson, Frye, Herbkersman, Hodges, Huggins, McLeod, Ott, E. H. Pitts, Spires and Toole: A CONCURRENT RESOLUTION TO RECOGNIZE AND HONOR JIM MANSHIP OF BEAUFORT COUNTY FOR UNCOMMON VALOR IN THE HEROIC RESCUE OF TWO WOMEN TRAPPED IN A SINKING CAR.
The Concurrent Resolution was adopted, ordered returned to the House.
REPORTS OF STANDING COMMITTEE
Senator HAYES from the Committee on Medical Affairs submitted a majority favorable and Senators BRYANT and ANDERSON a minority unfavorable report on:
S. 1031 (Word version) -- Senators Hayes, Reese, O'Dell, Jackson, Rose, Coleman, Nicholson, Ford, Elliott, Bright, Campbell, Massey and Matthews: A BILL TO AMEND SECTION 40-45-110, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING, AMONG OTHER THINGS, TO LICENSURE OF PHYSICAL THERAPISTS AND GROUNDS FOR SANCTIONS AGAINST LICENSEES, SO AS TO REVISE THE PROHIBITION AGAINST A LICENSEE WHO IS INVOLVED IN THE DIVIDING, TRANSFERRING, ASSIGNING, REBATING, OR REFUNDING OF FEES RECEIVED FOR PROFESSIONAL SERVICES BY CERTAIN MEANS BY DELETING THE REFERENCE TO "WAGES", AS A MEANS OF ENGAGING IN THE PROHIBITED CONDUCT, AND TO FURTHER SPECIFY ARRANGEMENTS THAT MAY EXIST BETWEEN A PHYSICAL THERAPIST AND A PHYSICIAN WHICH MAY NOT BE CONSIDERED CONDUCT SUBJECT TO SANCTIONS BY THE BOARD OF PHYSICAL THERAPY EXAMINERS.
Ordered for consideration tomorrow.
Senator PEELER from the Committee on Medical Affairs submitted a favorable with amendment report on:
S. 1137 (Word version) -- Senator Fair: A BILL TO AMEND SECTION 44-53-398, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO MONITORING THE SALE OF PRODUCTS CONTAINING EPHEDRINE OR PSEUDOEPHEDRINE, SO AS TO ALSO MONITOR PHENYLPROPANOLAMINE AND THE SALE AND PURCHASE OF THESE PRODUCTS, TO MAKE IT ILLEGAL TO PURCHASE THESE PRODUCTS, TO PROVIDE THAT INFORMATION GATHERED FROM THE PURCHASER AT THE TIME OF THE SALE OF THESE PRODUCTS MUST BE ENTERED IN AN ELECTRONIC LOG, RATHER THAN A WRITTEN LOG, TO PROVIDE THAT THE INFORMATION MUST BE TRANSMITTED TO A CENTRAL DATA COLLECTION SYSTEM THAT WILL SUBMIT THIS INFORMATION TO SLED WHICH WILL MAINTAIN THIS INFORMATION TO ASSIST LAW ENFORCEMENT IN MONITORING THESE SALES AND PURCHASES, AND TO PROVIDE THAT A RETAILER OF THESE PRODUCTS MAY APPLY TO THE BOARD OF PHARMACY FOR AN EXEMPTION FROM THE ELECTRONIC LOG REQUIREMENT; AND BY ADDING CHAPTER 14 TO TITLE 23 SO AS TO PROVIDE THAT THE STATE LAW ENFORCEMENT DIVISION SHALL SERVE AS THE REPOSITORY FOR INFORMATION THE CENTRAL DATA COLLECTION GATHERS AND TRANSFERS TO SLED PERTAINING TO THE SALE AND PURCHASE OF PRODUCTS CONTAINING EPHEDRINE, PSEUDOEPHEDRINE, AND PHENYLPROPANOLAMINE.
Ordered for consideration tomorrow.
Senator PEELER from the Committee on Medical Affairs submitted a favorable with amendment report on:
H. 3170 (Word version) -- Reps. Gunn, Wylie, Hart, Loftis, R.L. Brown, Whipper and King: A JOINT RESOLUTION TO CREATE THE JOINT ELECTRONIC HEALTH INFORMATION STUDY COMMITTEE TO EXAMINE THE FEASIBILITY OF INCREASING THE USE OF HEALTH INFORMATION TECHNOLOGY AND ELECTRONIC PERSONAL HEALTH RECORDS, TO PROVIDE FOR THE STUDY COMMITTEE'S MEMBERSHIP, AND TO REQUIRE THE STUDY COMMITTEE TO REPORT ITS FINDINGS AND RECOMMENDATIONS TO THE GENERAL ASSEMBLY BEFORE JANUARY 1, 2010, AT WHICH TIME THE STUDY COMMITTEE IS ABOLISHED.
Ordered for consideration tomorrow.
Message from the House
Columbia, S.C., March 9, 2010
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has returned the following Bill to the Senate with amendments:
H. 3395 (Word version) -- Reps. Harrell, Thompson, Cooper, Erickson, Bingham, A.D. Young, Edge, Bedingfield, J.R. Smith, G.R. Smith, D.C. Smith, Bannister, Brady, Cato, Chalk, Forrester, Gambrell, Hamilton, Hiott, Horne, Long, Nanney, Parker, E.H. Pitts, Rice, Scott, Sottile, Stewart, Viers, White, Willis, Toole, Neilson, Bales, T.R. Young and Wylie: A BILL TO AMEND SECTION 11-11-310, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE GENERAL RESERVE FUND, SO AS TO MAKE CONFORMING AMENDMENTS TO REFLECT ANY CHANGE IN THE AMOUNT REQUIRED TO BE HELD IN THE GENERAL RESERVE FUND PURSUANT TO THE CONSTITUTION OF THIS STATE AND THE RATE OF REPLENISHMENT OF THAT AMOUNT.
Respectfully submitted,
Speaker of the House
The Bill was ordered placed on the Calendar for consideration tomorrow.
Message from the House
Columbia, S.C., March 9, 2010
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has returned the following Bill to the Senate with amendments:
H. 3396 (Word version) -- Reps. Harrell, Thompson, Scott, Cooper, Erickson, Bingham, A.D. Young, Edge, J.R. Smith, G.R. Smith, Bedingfield, Whitmire, Hiott, D.C. Smith, Bannister, Brady, Cato, Chalk, Forrester, Gambrell, Hamilton, Horne, Long, Nanney, Parker, E.H. Pitts, Rice, Sottile, Stewart, Viers, White, Willis, Toole, Neilson, Bales, T.R. Young and Wylie: A JOINT RESOLUTION PROPOSING AN AMENDMENT TO SECTION 36, ARTICLE III OF THE CONSTITUTION OF SOUTH CAROLINA, 1895, RELATING TO THE GENERAL RESERVE FUND AND THE CAPITAL RESERVE FUND, SO AS TO INCREASE FROM THREE TO FIVE PERCENT THE AMOUNT OF STATE GENERAL FUND REVENUE IN THE LATEST COMPLETED FISCAL YEAR REQUIRED TO BE HELD IN THE GENERAL RESERVE FUND.
Respectfully submitted,
Speaker of the House
The Joint Resolution was ordered placed on the Calendar for consideration tomorrow.
HOUSE CONCURRENCES
S. 1095 (Word version) -- Senators Cleary, Cromer, Campsen, Land and Davis: A CONCURRENT RESOLUTION TO OPPOSE ANY FISHING AREA CLOSURES OFF THE COAST OF SOUTH CAROLINA ASSOCIATED WITH THE SOUTH ATLANTIC FISHERY MANAGEMENT COUNCIL'S PROPOSED AMENDMENT 17A TO THE FISHERY MANAGEMENT PLAN FOR THE SNAPPER GROUPER FISHERY OF THE SOUTH ATLANTIC REGION.
Returned with concurrence.
S. 1121 (Word version) -- Senators Mulvaney and Sheheen: A CONCURRENT RESOLUTION TO REQUEST THAT THE DEPARTMENT OF TRANSPORTATION NAME THE BRIDGE ON SANDHILL ROAD IN KERSHAW, SOUTH CAROLINA, AS THE "LEIGH ALLISON SHEPARD MEMORIAL BRIDGE" AND ERECT APPROPRIATE MARKERS OR SIGNS AT THIS BRIDGE THAT CONTAIN THE WORDS "LEIGH ALLISON SHEPARD MEMORIAL BRIDGE".
Returned with concurrence.
THE SENATE PROCEEDED TO A CALL OF THE UNCONTESTED LOCAL AND STATEWIDE CALENDAR.
ORDERED ENROLLED FOR RATIFICATION
The following Joint Resolution was read the third time and, having received three readings in both Houses, it was ordered that the title be changed to that of an Act and enrolled for Ratification:
H. 4485 (Word version) -- Reps. A.D. Young, Horne, Knight and Harrell: A JOINT RESOLUTION TO AUTHORIZE THE STATE BUDGET AND CONTROL BOARD TO TRANSFER OWNERSHIP OF SUMMERVILLE NATIONAL GUARD ARMORY IN SUMMERVILLE, SOUTH CAROLINA, TO THE TOWN OF SUMMERVILLE.
Senator ROSE asked unanimous consent to take the Joint Resolution up for immediate consideration.
There was no objection and the Resolution was read the third time and ordered enrolled for Ratification.
The following Bills and Joint Resolution were read the third time and ordered sent to the House of Representatives:
S. 591 (Word version) -- Senators Lourie and Malloy: A BILL TO AMEND SECTIONS 22-3-1330, 22-3-1340, 22-3-1370, 22-3-1400, AND 22-3-1410 OF THE 1976 CODE, ALL RELATING TO PROCEEDINGS IN CLAIM AND DELIVERY ACTIONS, TO ALLOW SERVICE OF PROCESS BY PERSONS OTHER THAN CONSTABLES.
S. 591--Recorded Vote
Senators RYBERG and BRYANT desired to be recorded as voting in favor of the third reading of the Bill.
S. 718 (Word version) -- Senators Campsen and Malloy: A BILL TO AMEND SECTION 22-3-550 OF THE 1976 CODE, RELATING TO ORDERING RESTITUTION IN MAGISTRATE'S COURT, TO PROVIDE THAT A MAGISTRATE HAS JURISDICTION OF ALL OFFENSES WHICH MAY BE SUBJECT TO THE PENALTIES OF A FINE OR FORFEITURE NOT EXCEEDING ONE THOUSAND DOLLARS AND TO PROVIDE THAT A MAGISTRATE MAY ORDER RESTITUTION IN AN AMOUNT NOT TO EXCEED THE CIVIL JURISDICTIONAL AMOUNT FOR MAGISTRATES.
S. 718--Recorded Vote
Senators RYBERG and BRYANT desired to be recorded as voting in favor of the third reading of the Bill.
S. 879 (Word version) -- Senator Campsen: A BILL TO AMEND SECTION 12-37-3150, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO ASSESSABLE TRANSFERS OF INTEREST FOR PURPOSES OF DETERMINING THE VALUE OF REAL PROPERTY FOR PROPERTY TAXATION, SO AS TO PROVIDE ADDITIONAL INSTANCES OF PROPERTY TRANSFERS NOT CONSIDERED ASSESSABLE TRANSFERS OF INTEREST, INCLUDING TRANSFERS OF FRACTIONAL INTERESTS CONSTITUTING NOT MORE THAN FIFTY PERCENT OF FEE SIMPLE TITLE, TRANSFERS INTO AND OUT OF A SINGLE MEMBER LIMITED LIABILITY COMPANY NOT TAXED AS A CORPORATION WHEN THE SINGLE MEMBER IS THE TRANSFEREE AND TRANSFEROR, TRANSFERS RELATING TO EASEMENTS, TRANSFERS TO QUIET TITLE OR ESTABLISH A BOUNDARY LINE, AND TRANSFERS CREATING OR TERMINATING A JOINT TENANCY WITH RIGHTS OF SURVIVORSHIP IF THE GRANTORS AND GRANTEES ARE THE SAME.
S. 879--Recorded Vote
Senators RYBERG and BRYANT desired to be recorded as voting in favor of the third reading of the Bill.
S. 905 (Word version) -- Senators Leatherman and Elliott: A BILL TO AMEND SECTION 2-7-71 OF THE 1976 CODE, RELATING TO TAX BILLS AND REVENUE IMPACT STATEMENTS, TO PROVIDE THAT THE REVENUE IMPACT STATEMENT MUST BE SIGNED BY THE CHIEF ECONOMIST OF THE OFFICE OF RESEARCH AND STATISTICS; AND TO AMEND SECTION 2-7-78, RELATING TO THE CERTIFICATION OF A REVENUE ESTIMATE, TO PROVIDE THAT THE REVENUE IMPACT MUST BE CERTIFIED BY THE CHIEF ECONOMIST OF THE OFFICE OF RESEARCH AND STATISTICS.
S. 905--Recorded Vote
Senators RYBERG and BRYANT desired to be recorded as voting in favor of the third reading of the Bill.
S. 931 (Word version) -- Senator L. Martin: A BILL TO AMEND SECTION 44-48-40 OF THE 1976 CODE, RELATING TO THE EFFECTIVE DATE OF PAROLE OR CONDITIONAL RELEASE OF SEXUALLY VIOLENT PREDATORS, TO PROVIDE THAT WRITTEN NOTICE MUST BE GIVEN TWO HUNDRED SEVENTY DAYS RATHER THAN ONE HUNDRED DAYS, AND TO PROVIDE THAT THE PAROLE OR CONDITIONAL RELEASE ORDER DOES NOT TAKE EFFECT FOR ONE HUNDRED EIGHTY DAYS, RATHER THAN NINETY DAYS, AFTER ISSUANCE OF THE ORDER; TO AMEND SECTION 44-48-80, RELATING TO THE FACILITY IN WHICH A PERSON MUST BE HELD AFTER PROBABLE CAUSE IS FOUND TO EXIST THAT THE PERSON IS A SEXUALLY VIOLENT PREDATOR, TO REQUIRE THAT THE PERSON ONLY BE HELD IN A LOCAL OR REGIONAL DETENTION FACILITY PENDING CONCLUSION OF THE PROCEEDINGS IN THIS CHAPTER AND THAT THE COURT MUST DIRECT THE PERSON TO BE TRANSPORTED TO AN APPROPRIATE FACILITY OF THE SOUTH CAROLINA DEPARTMENT OF MENTAL HEALTH; TO AMEND SECTION 44-48-90, RELATING TO THE TIME WITHIN WHICH A JURY TRIAL MUST BE REQUESTED AND HELD TO DETERMINE IF A PERSON IS A SEXUALLY VIOLENT PREDATOR, TO PROVIDE THAT A JURY TRIAL MUST BE REQUESTED WITHIN THIRTY DAYS AFTER THE DETERMINATION OF PROBABLE CAUSE UNDER SECTION 44-48-80, TO PROVIDE THAT THE TRIAL MUST BE HELD WITHIN NINETY DAYS OF ISSUANCE OF THE COURT APPOINTED EVALUATOR'S OPINION, AND TO PROVIDE THAT UPON RECEIPT OF THE ISSUANCE OF THE OPINION, EITHER PARTY MAY RETAIN HIS OWN EXPERT TO CONDUCT A SUBSEQUENT EVALUATION; TO AMEND SECTION 44-48-100, RELATING TO THE FACILITY IN WHICH A PERSON MUST BE HELD UPON A MISTRIAL IN DETERMINING IF THE PERSON IS A SEXUALLY VIOLENT PREDATOR, TO REQUIRE THAT THE PERSON ONLY BE HELD IN A LOCAL OR REGIONAL DETENTION FACILITY; AND TO AMEND SECTION 44-48-120, RELATING TO PROCEDURES REQUIRED WHEN THE DIRECTOR OF THE DEPARTMENT OF MENTAL HEALTH DETERMINES A PERSON COMMITTED TO THE DEPARTMENT AS A SEXUALLY VIOLENT PREDATOR IS NO LONGER LIKELY TO COMMIT ACTS OF SEXUAL VIOLENCE, TO REQUIRE THE DIRECTOR TO CERTIFY THIS DETERMINATION IN WRITING AND TO NOTIFY THE ATTORNEY GENERAL OF THIS CERTIFICATION AND OF THE PATIENT'S AUTHORIZATION TO PETITION THE COURT FOR RELEASE, TO PROVIDE THAT THE ATTORNEY GENERAL MAY REQUEST AN EXAMINATION BEFORE A HEARING ON THE RELEASE IS HELD, AND TO PROVIDE THAT EITHER PARTY MAY REQUEST THAT THE HEARING BE HELD BEFORE A JURY.
S. 931--Recorded Vote
Senators RYBERG and BRYANT desired to be recorded as voting in favor of the third reading of the Bill.
S. 1028 (Word version) -- Senator Leventis: A BILL TO AMEND SECTION 32-8-320, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO PERSONS WHO MAY SERVE AS A DECEDENT'S AGENT TO AUTHORIZE CREMATION, SO AS TO ALSO PERMIT A PERSON NAMED IN THE DECEDENT'S DD FORM 93 TO AUTHORIZE CREMATION IF THE DECEDENT SERVED IN THE MILITARY SERVICES IF THERE IS NO SUCH DESIGNATION IN THE WILL OR OTHER VERIFIED AND ATTESTED DOCUMENT OF THE DECEDENT.
S. 1028--Recorded Vote
Senators RYBERG and BRYANT desired to be recorded as voting in favor of the third reading of the Bill.
S. 1147 (Word version) -- Senators McConnell, Rankin, Hutto, Campbell, Knotts and Alexander: A BILL TO AMEND SECTION 23-47-10, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO DEFINITION OF TERMS ASSOCIATED WITH THE PUBLIC SAFETY COMMUNICATIONS CENTER, SO AS TO REVISE THE DEFINITION OF SEVERAL EXISTING TERMS AND TO PROVIDE DEFINITIONS FOR SEVERAL NEW TERMS; TO AMEND SECTION 23-47-20, AS AMENDED, RELATING TO 911 SYSTEM SERVICE REQUIREMENTS, SO AS TO DELETE "A CAPABILITY TO HAVE CELLULAR PHONES ROUTED TO 911" AS A SYSTEM REQUIREMENT AND TO ADD "ROUTING AND CAPABILITIES TO RECEIVE AND PROCESS CMRS SERVICE AND VOIP SERVICE CAPABLE OF MAKING 911 CALLS" AS A SYSTEM REQUIREMENT; TO AMEND SECTION 23-47-50, RELATING TO SUBSCRIBER BILLING OR 911 SERVICE, SO AS TO PROVIDE THAT FOR THE BILLING OF 911 CHARGES FOR LOCAL EXCHANGE ACCESS FACILITIES THAT ARE CAPABLE OF SIMULTANEOUSLY CARRYING FIVE OR MORE OUTGOING 911 VOICE CALLS, TO REVISE THE 911 CHARGE THAT PREPAID WIRELESS TELECOMMUNICATIONS SERVICE IS SUBJECT TO AND TO MAKE TECHNICAL CHANGES; TO AMEND SECTION 23-47-65, RELATING TO THE CMRS EMERGENCY TELEPHONE ADVISORY COMMITTEE, SO AS TO REVISE THE NAME OF THE COMMITTEE AND ITS MEMBERSHIP, TO MAKE TECHNICAL CHANGES, AND TO PROVIDE THAT THE COMMITTEE AND THE STATE BUDGET AND CONTROL BOARD ARE AUTHORIZED TO REGULATE PREPAID WIRELESS SELLERS; BY ADDING SECTION 23-47-67 SO AS TO IMPOSE A VOIP 911 CHARGE ON EACH LOCAL EXCHANGE ACCESS FACILITY, AND TO PROVIDE FOR THE COLLECTION OF THE CHARGE AND ITS DISTRIBUTION; BY ADDING SECTION 23-47-68 SO AS TO IMPOSE A PREPAID WIRELESS 911 CHARGE, AND TO PROVIDE FOR ITS COLLECTION AND DISTRIBUTION; BY ADDING SECTION 23-47-69 SO AS TO LIMIT THE CHARGES THAT MAY BE IMPOSED FOR 911 SERVICE; AND TO AMEND SECTION 23-47-70, RELATING TO LIABILITY FOR DAMAGES THAT MAY OCCUR FROM A GOVERNMENTAL AGENCY PROVIDING 911 SERVICE, SO AS TO PROVIDE FOR LIABILITY WHEN 911 SERVICE IS PROVIDED AND WHEN IT IS NOT PROVIDED PURSUANT TO TARIFFS ON FILE WITH THE PUBLIC SERVICE COMMISSION AND TO MAKE A TECHNICAL CHANGE.
S. 1175 (Word version) -- Senator Land: A BILL TO AMEND SECTION 9-8-20, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE ESTABLISHMENT OF THE RETIREMENT SYSTEM FOR JUDGES AND SOLICITORS OF THE STATE OF SOUTH CAROLINA, SO AS TO PROVIDE THAT A PERSON ASSUMING THE OFFICE OF ATTORNEY GENERAL OF THIS STATE AFTER 2010, MUST BE A MEMBER OF THAT RETIREMENT SYSTEM AND TO MAKE THE NECESSARY PROVISIONS FOR THE ATTORNEY GENERAL TO BECOME A MEMBER OF THE RETIREMENT SYSTEM FOR JUDGES AND SOLICITORS OF THE STATE OF SOUTH CAROLINA.
Senator LAND explained the Bill.
S. 1175--Recorded Vote
Senators RYBERG and BRYANT desired to be recorded as voting in favor of the third reading of the Bill.
S. 1251 (Word version) -- Judiciary Committee: A JOINT RESOLUTION TO APPROVE REGULATIONS OF THE BOARD OF FUNERAL SERVICE, RELATING TO FUNERAL SERVICE PRACTICE ACT, DESIGNATED AS REGULATION DOCUMENT NUMBER 4068, PURSUANT TO THE PROVISIONS OF ARTICLE 1, CHAPTER 23, TITLE 1 OF THE 1976 CODE.
S. 1251--Recorded Vote
Senators RYBERG and BRYANT desired to be recorded as voting in favor of the third reading of the Joint Resolution.
AMENDMENT PROPOSED, CARRIED OVER
H. 3365 (Word version)--Reps. Cooper, T.R. Young and J.R. Smith: A BILL TO ENACT THE SOUTH CAROLINA HIGHER EDUCATION EFFICIENCY AND ADMINISTRATIVE POLICIES ACT OF 2009, RELATING TO HIGHER EDUCATION, BY ADDING ARTICLE 5 TO PROVIDE FOR HUMAN RESOURCES POLICIES, PROCEDURES, AND REQUIREMENTS FOR PUBLIC INSTITUTIONS OF HIGHER LEARNING IN THIS STATE; BY ADDING SECTION 2-47-53 SO AS TO PROVIDE FOR THE ESTABLISHMENT OF PERMANENT IMPROVEMENT PROJECTS FOR THE STATE'S INSTITUTIONS OF HIGHER LEARNING; TO AMEND SECTION 1-11-65, RELATING TO APPROVAL OF REAL PROPERTY TRANSACTIONS BY THE STATE BUDGET AND CONTROL BOARD, TO EXEMPT CERTAIN REAL PROPERTY TRANSACTIONS MADE FOR OR BY THESE INSTITUTIONS OF HIGHER LEARNING; BY ADDING SECTIONS 59-147-35 AND 59-147-36 AND TO AMEND SECTION 59-147-30, RELATING TO THE PROCEDURES FOR THE ISSUANCE OF REVENUE BONDS, TO REVISE THESE PROCEDURES AND THE PURPOSES FOR WHICH THE BONDS MAY BE USED; BY ADDING SECTION 6-1-135 TO PROVIDE THAT WHEN A COUNTY, MUNICIPALITY, OR SCHOOL DISTRICT ENTERS INTO A CONTRACT WITH A VENDOR TO ACQUIRE GOODS OR SERVICES, A FOUR-YEAR OR GRADUATE LEVEL PUBLIC INSTITUTION OF HIGHER LEARNING LOCATED IN THE COUNTY, MUNICIPALITY, OR SCHOOL DISTRICT MAY BECOME A PARTY TO THE CONTRACT; BY ADDING SECTION 59-112-115 TO PROVIDE THAT WHENEVER THE GOVERNING BOARD OF A FOUR-YEAR AND GRADUATE LEVEL PUBLIC INSTITUTION OF HIGHER LEARNING IN THIS STATE NOT INCLUDING A TECHNICAL COLLEGE ADOPTS A CHANGE TO THE TUITION OR FEES IMPOSED ON STUDENTS, THE CHANGE ONLY MAY BE IMPLEMENTED BY THE INSTITUTION AFTER A PUBLICALLY RECORDED ROLL CALL VOTE. (ABBREVIATED TITLE)
The Senate proceeded to a consideration of the Bill, the question being the adoption of the amendment proposed by the Committee on Education.
The Committee on Education proposed the following amendment (3365FIN001), which was adopted:
Amend the bill, as and if amended, by striking all after the enacting words and inserting:
/ Part I
Citation
SECTION 1. This act is known and may be cited as the "South Carolina Higher Education Efficiency and Administrative Policies Act of 2010".
Part II
Human Resource Reforms
SECTION 2. Chapter 101, Title 59 of the 1976 Code is amended by adding:
"Article 5
Human Resources at a Public Institution
of Higher Learning
Section 59-101-1010. As used in this article, 'public institution of higher learning', or 'institution' means a four-year public institution of higher learning or graduate level public institution of higher learning, including two-year branch campuses of a graduate level public institution of higher learning in this state, not including technical colleges.
Section 59-101-1020. The Budget and Control Board's State Office of Human Resources shall participate with five representatives selected by the respective presidents of the public institutions of higher learning to represent all of the public institutions of higher learning to study, develop, and recommend a separate, comprehensive human resources system for the public institutions of higher learning. The recommendation shall include, but not be limited to, prescription of a methodology to establish a uniform compensation and classification plan among the public institutions of higher learning. The recommendations must provide for necessary accountability to the Budget and Control Board, including a process for reporting human resources data. The recommendation must be submitted to the State Budget and Control Board for its review no later than July 1, 2011 and shall not be implemented until approved by the Budget and Control Board pursuant to Section 8-11-230."
Part III
Facilities and Capital Expenditure Revisions
SECTION 3. Section 2-47-50 of the 1976 Code is amended to read:
"Section 2-47-50. The board shall establish formally each permanent improvement project before actions of any sort which implement the project in any way may be undertaken and no expenditure of any funds for any services or for any other project purpose contracted for, delivered, or otherwise provided prior to the date of the formal action of the board to establish the project shall be approved. State agencies and institutions may advertise and interview for project architectural and engineering services for a pending project so long as the architectural and engineering contract is not awarded until after a state project number is assigned. After the committee has reviewed the form to be used to request the establishment of permanent improvement projects and has reviewed the time schedule for considering such requests as proposed by the board, requests to establish permanent improvement projects shall be made in such form and at such times as the board may require.
Any proposal to finance all or any part of any project using any funds not previously authorized specifically for the project by the General Assembly or using any funds not previously approved for the project by the board and reviewed by the committee shall be referred to the committee for review prior to approval by the board.
Any proposed revision of the scope or of the budget of an established permanent improvement project deemed by the board to be substantial shall be referred to the committee for its review prior to any final action by the board. In making their determinations regarding changes in project scope, the board and the committee shall utilize the permanent improvement project proposal and justification statements, together with any supporting documentation, considered at the time the project was authorized or established originally. Any proposal to increase the budget of a previously approved project using any funds not previously approved for the project by the board and reviewed by the committee shall in all cases be deemed to be a substantial revision of a project budget which shall be referred to the committee for review. The committee shall be advised promptly of all actions taken by the board which approve revisions in the scope of or the budget of any previously established permanent improvement project not deemed substantial by the board. However, with regard to institutions of higher learning as defined in Section 59-101-1010, a previously approved permanent improvement project, whose total costs increase not more than ten percent of the most recently approved total costs, not to exceed two million dollars in the aggregate for all the revisions made pursuant to this section, is not required to have that proposal reviewed by the committee, except that the proposal is subject to staff level review.
For purposes of this chapter, with regard to all institutions of higher learning, except institutions of higher learning as defined in Section 59-101-1010, permanent improvement project is defined as:
(1) acquisition of land, regardless of cost;
(2) acquisition, as opposed to the construction, of buildings or other structures, regardless of cost;
(3) construction of additional facilities and work on existing facilities for any given project including their renovation, repair, maintenance, alteration, or demolition in those instances in which the total cost of all work involved is five hundred thousand dollars or more;
(4) architectural and engineering and other types of planning and design work, regardless of cost, which is intended to result in a permanent improvement project. Master plans and feasibility studies are not permanent improvement projects and are not to be included;
(5) capital lease purchase of a facility acquisition or construction; and
(6) equipment that either becomes a permanent fixture of a facility or does not become permanent but is included in the construction contract shall be included as a part of a project.
For purposes of this chapter, with regard to all institutions of higher learning, as defined in Section 59-101-1010, 'permanent improvement project' is defined as:
(1) acquisition of land costing more than two hundred fifty thousand dollars. For the acquisition of land costing two hundred fifty thousand dollars or less, the proposal is subject to staff level review;
(2) acquisition, as opposed to the construction, of buildings or other structures costing more than two hundred fifty thousand dollars. For the acquisition, as opposed to construction, of building or other structures costing two hundred fifty thousand dollars or less, the proposal is subject to staff level review;
(3) work on existing facilities for any given project including their renovation, repair, maintenance, alteration, or demolition in those instances in which the total cost of all work involved is one million dollars or more;
(4) architectural and engineering and other types of planning and design work, regardless of cost, which is intended to result in a permanent improvement project. Master plans and feasibility studies are not permanent improvement projects and are not to be included;
(5) capital lease purchase of a facility acquisition or construction in which the total cost is one million dollars or more;
(6) equipment that either becomes a permanent fixture of a facility or does not become permanent but is included in the construction contract shall be included as a part of a project in which the total cost is one million dollars or more; and
(7) new construction of a facility that exceeds a total cost of five hundred thousand dollars.
Any permanent improvement project that meets the above definition must become a project, regardless of the source of funds. However, an institution of higher learning that has been authorized or appropriated capital improvement bond funds, capital reserve fund or state appropriated funds, or state infrastructure bond funds, or state institution bond funds by the General Assembly for capital improvements shall process a permanent improvement project, regardless of the amount.
For purposes of this chapter, Clemson University Public Service Activities (Clemson--PSA) and South Carolina State University Public Service Activities (SC State-PSA) shall be considered an institution of higher learning as defined in Section 59-101-1010."
SECTION 4. Section 1-11-65 of the 1976 Code is amended by adding an appropriately lettered subsection at the end to read:
"( ) Any public institution of higher learning as defined in Section 59-101-1010 with approval of the Budget and Control Board may enter into one or more ground lease agreements with a private entity whereby the private entity will provide all services necessary for the creation and operation of on-campus infrastructure including, but not limited to, financing which is subject to review and approval of state treasurer, designing, constructing, managing, operating, maintaining, and related services. Upon expiration of the ground lease agreement term, the private entity shall surrender to the institution such premises with the existing buildings, other structures, and improvements constructed and located thereon and therein, in the same condition as when the construction of the buildings, other structures, and improvements were completed, only natural and normal wear and tear excepted. The Budget and Control Board shall approve all ground lease agreement terms and conditions including the consideration involved. The full faith and credit of the State toward the lease obligations must not be pledged, and any statement to the contrary is deemed null and void as a matter of public policy. The private entity may be a nonprofit organization. Budget and Control Board approval required is instead of or a substitute for any other approval required by any other provision of law or regulation in connection with the undertaking of the private entity and the subject institution; however, the private entity and the subject institution shall adhere to fire, life, and safety codes as required by the Office of the State Engineer. This section and the approval required by this section does not exempt any transaction or entity from complying with Chapter 35, Title 11."
Part IV
Procurement Code Revisions
SECTION 5. Section 11-35-1550(2) of the 1976 Code, as last amended by Act 376 of 2006, is further amended to read:
"(2) Competition and Price Reasonableness.
(a) Purchases not in excess of two thousand five hundred dollars. Except as provided in subitem (d) below, small purchases not exceeding two thousand five hundred dollars may be accomplished without securing competitive quotations if the prices are considered reasonable. The purchasing office must annotate the purchase requisition: 'Price is fair and reasonable' and sign. The purchases must be distributed equitably among qualified suppliers. When practical, a quotation must be solicited from other than the previous supplier before placing a repeat order. The administrative cost of verifying the reasonableness of the price of purchase 'not in excess of' may more than offset potential savings in detecting instances of overpricing. Action to verify the reasonableness of the price need be taken only when the procurement officer of the governmental body suspects that the price may not be reasonable, comparison to previous price paid, or personal knowledge of the item involved.
(b) Purchases over two thousand five hundred dollars to ten thousand dollars. Except as provided in subitem (d) below, solicitation of written quotes from a minimum of three qualified sources of supply must be made and documentation of the quotes attached to the purchase requisition for a small purchase over two thousand five hundred dollars but not in excess of ten thousand dollars. The award must be made to the lowest responsive and responsible sources.
(c) Purchases over ten thousand dollars up to fifty thousand dollars. Written solicitation of written quotes, bids, or proposals must be made for a small purchase over ten thousand dollars but not in excess of fifty thousand dollars. The procurement must be advertised at least once in the South Carolina Business Opportunities publication or through a means of central electronic advertising as approved by the designated board office. A copy of the written solicitation and written quotes must be attached to the purchase requisition. The award must be made to the lowest responsive and responsible source or, when a request for proposal process is used, the highest ranking offeror.
(d) For institutions of higher learning as defined in Section 59-101-1010, small purchase amounts to which the provisions of subitem (a) above shall apply are those purchases not exceeding ten thousand dollars, and for these purchases subitem (b) above shall not apply. In addition, purchasing cards of the institution for these purchases also may be used by officials or employees of the institution as the governing board thereof approves."
SECTION 6. Section 11-35-3310 of the 1976 Code, as last amended by Act 174 of 2008, is further amended to read:
"Section 11-35-3310. (1) General Applicability. Indefinite delivery contracts may be awarded on an as-needed basis for construction services pursuant to the procedures in Section 11-35-3015(2)(b) and for architectural-engineering and land surveying services pursuant to Section 11-35-3220.
(a) Construction Services. When construction services contracts are awarded, each contract shall be limited to a total expenditure of seven hundred fifty thousand dollars for a two-year period with individual project expenditures not to exceed one hundred fifty thousand dollars; provided, that these limits for institutions of higher learning as defined in Section 59-101-1010 in this item shall be one million dollars for total expenditures and two hundred fifty thousand dollars for individual expenditures within the time periods specified.
(b) Architectural-Engineering and Land Surveying Services. When architectural-engineering and land surveying services contracts are awarded, each contract shall be limited to a total expenditure of three hundred thousand dollars for a two-year period with individual project expenditures not to exceed one hundred thousand dollars; provided, that these limits for institutions of higher learning as defined in Section 59-101-1010 in this item shall be five hundred thousand dollars for total expenditures and two hundred thousand dollars for individual expenditures within the time periods specified.
(2) Small Indefinite Delivery Contracts. Small indefinite delivery contracts for architectural-engineering and land surveying services may be procured as provided in Section 11-35-3230. A contract established under this section shall be subject to Section 11-35-3230, and any regulations promulgated thereunder except that the individual and total contract limits shall be fifty and one hundred fifty thousand dollars respectively for institutions of higher learning as defined in Section 59-101-1010."
SECTION 7. Section 11-35-4810 of the 1976 Code is amended to read:
"Section 11-35-4810. Any public procurement unit may participate in, sponsor, conduct, or administer a cooperative purchasing agreement for the procurement of any supplies, services, or construction with one or more public procurement units or external procurement activities in accordance with an agreement entered into between the participants. Such cooperative purchasing may include, but is not limited to, joint or multi-party contracts between public procurement units and open-ended state public procurement unit contracts which shall be made available to local public procurement units, except as provided in Section 11-35-4820 or except as may otherwise be limited by the board through regulations.
However, thirty days notice of a proposed multi-state solicitation shall be provided through central advertising and such contracts may be only awarded to manufacturers who will be distributing the products to South Carolina governmental bodies through South Carolina vendors; provided, however, that the provisions of this paragraph do not apply to institutions of higher learning as defined in Section 59-101-1010, if the institution demonstrates a cost savings to the Office of State Procurement in regard to the multi-state solicitation and procurement."
Part V
Miscellaneous Provisions
SECTION 8. Section 1-7-170 of the 1976 Code, as added by Act 353 of 2008, is amended to read:
"Section 1-7-170. (A) A department or agency of state government may not engage on a fee basis an attorney at law except upon the written approval of the Attorney General and upon a fee as must be approved by him. This section does not apply to the employment of attorneys in special cases in inferior courts when the fee to be paid does not exceed two hundred fifty dollars or exceptions approved by the State Budget and Control Board. This section does not apply to an attorney hired by the General Assembly or the judicial department.
(B) Notwithstanding the provisions of subsection (A), when a public institution of higher learning, as defined in Section 59-101-1010, decides to employ outside counsel on a particular matter, except in matters involving public financing or related financing issues, for a series of similar matters, or on a retainer basis shall submit the names of three qualified law firms consisting of a single practitioner or a group of practitioners from which the Attorney General shall approve one or more which the institution is then authorized to employ or retain. Subject to approval by the Attorney General, the institution may pay legal fees to that firm at its usual and customary rates for engaging in that type of work. Attorneys employed in matters involving public financing or related financing issues must be assigned and approved by the Budget and Control Board according to policies and procedures adopted by the board."
SECTION 9. Article 1, Chapter 101, Title 59 of the 1976 Code is amended by adding:
"Section 59-101-55. State appropriated funds shall not be used to provide out-of-state subsidies to students attending state-supported institutions of higher learning."
SECTION 10. Section 59-101-620 of the 1976 Code is amended to read:
"Section 59-101-620. (A) A public institution of higher learning may offer educational fee waivers to no more than four percent of the undergraduate student body; however, an institution of higher learning, as defined in Section 59-101-1010, may offer educational fee waivers to not more than eight percent of the undergraduate student body. Any fee waivers above four percent must be used for in-state students. For the purposes of fee waivers, an in-state student shall be defined by Section 59-112-20(A).
(B) State-supported institutions of higher learning to which subsection (A) applies shall annually report to the Commission on Higher Education the amount of such waivers provided during that fiscal year and such other information as the commission may require in regard to these waivers."
SECTION 11. Chapter 112, Title 59 of the 1976 Code is amended by adding:
"Section 59-112-115. Whenever the governing board of an institution of higher learning as defined in Section 59-101-1010, adopts a change to the tuition or fees imposed on students, the change may be implemented by the institution only after a public vote with the number of trustees voting for and against the change being counted. A majority vote shall be required to implement any change to the tuition or fees."
Part VI
Severability and Time Effective
SECTION 12. If any section, subsection, item, subitem, paragraph, subparagraph, sentence, clause, phrase, or word of this act is for any reason held to be unconstitutional or invalid, such holding shall not affect the constitutionality or validity of the remaining portions of this act, the General Assembly hereby declaring that it would have passed this act, and each and every section, subsection, item, subitem, paragraph, subparagraph, sentence, clause, phrase, and word thereof, irrespective of the fact that any one or more other sections, subsections, items, subitems, paragraphs, subparagraphs, sentences, clauses, phrases, or words hereof may be declared to be unconstitutional, invalid, or otherwise ineffective.
SECTION 13. Unless otherwise provided, this act takes effect upon approval by the Governor. /
Renumber sections to conform.
Amend title to conform.
Senator COURSON explained the committee amendment.
Senator BRYANT proposed the following amendment (3365R001.KLB):
Amend the bill, as and if amended, in Section 11-35-1550(2)(d), as found in SECTION 5:
/ (d)(i) For institutions of higher learning as defined in Section 59-101-1010, small purchase amounts to which the provisions of subitem (a) above shall apply are those purchases not exceeding ten thousand dollars, and for these purchases subitem (b) above shall not apply. In addition, purchasing cards of the institution for these purchases also may be used by officials or employees of the institution as the governing board thereof approves.
(ii) an institution of higher learning must maintain a transaction register that records all of its small purchases made pursuant to subitem (b)(i). Entries in the register must include a description of and the amount of the purchase. The register must be prominently posted on the institution's internet website and made available for public viewing and downloading." /
Amend the bill further, as and if amended, in SECTION 6 by adding a new subsection to Section 11-35-3310 to read:
/ (3) Expenditures made pursuant to this section by institutions of higher learning as defined in Section 59-101-1010 must maintained in a transaction register by the institution making the expenditure. Entries in the register must include a description of and the amount of the expenditure. The register must be prominently posted on the institution's internet website and made available for public viewing and downloading." /
Amend the bill further, as and if amended, in SECTION 7, by adding a new sentence at the end of the second paragraph to read:
/ Purchasing agreements that are exempted from this section which are entered into by institutions of higher learning must be maintained in a transaction register. Entries in the register must include a description of and the amount of the agreement. The register must be prominently posted on the institution's internet website and made available for public viewing and downloading." /
Amend the bill further, as and if amended, in SECTION 8, by striking Section 1-7-170(B) and inserting:
/ (B) Notwithstanding the provisions of subsection (A), when a public institution of higher learning, as defined in Section 59-101-1010, decides to employ outside counsel on a particular matter, except in matters involving public financing or related financing issues, for a series of similar matters, or on a retainer basis shall submit the names of three qualified law firms consisting of a single practitioner or a group of practitioners from which the Attorney General shall approve one or more which the institution is then authorized to employ or retain. Subject to approval by the Attorney General, the institution may pay legal fees to that firm at its usual and customary rates for engaging in that type of work. Attorneys employed in matters involving public financing or related financing issues must be assigned and approved by the Budget and Control Board according to policies and procedures adopted by the board. A record of all legal fees paid must be must be maintained in a transaction register. Entries in the register must include a description of the legal services rendered to the institution and the amount of the fees paid for the legal services. The register must be prominently posted on the institution's internet website and made available for public viewing and downloading." /
Amend the bill further, as and if amended, in SECTION 10 by striking Section 59-101-620(B) and inserting:
/ (B) State-supported institutions of higher learning to which subsection (A) applies shall annually report to the Commission on Higher Education the amount of such waivers provided during that fiscal year and such other information as the commission may require in regard to these waivers. The report made to the Commission on Higher Education must be prominently posted on the institution's internet website and made available for public viewing and downloading." /
Renumber sections to conform.
Amend title to conform.
Senator BRYANT explained the amendment.
On motion of Senator BRYANT, the Bill was carried over, as amended.
S. 1221 (Word version) -- Senator Knotts: A CONCURRENT RESOLUTION TO FIX WEDNESDAY, APRIL 14, 2010, AT NOON AS THE DATE AND TIME FOR THE HOUSE OF REPRESENTATIVES AND THE SENATE TO MEET IN JOINT SESSION IN THE HALL OF THE HOUSE OF REPRESENTATIVES FOR THE PURPOSE OF ELECTING MEMBERS OF THE BOARDS OF TRUSTEES FOR THE CITADEL, CLEMSON UNIVERSITY, COLLEGE OF CHARLESTON, COASTAL CAROLINA UNIVERSITY, FRANCIS MARION UNIVERSITY, LANDER UNIVERSITY, THE MEDICAL UNIVERSITY OF SOUTH CAROLINA, SOUTH CAROLINA STATE UNIVERSITY, THE UNIVERSITY OF SOUTH CAROLINA, WIL LOU GRAY OPPORTUNITY SCHOOL, AND WINTHROP UNIVERSITY TO SUCCEED THOSE MEMBERS WHOSE TERMS EXPIRE IN 2010, OR WHOSE POSITIONS OTHERWISE MUST BE FILLED; AND TO ESTABLISH A PROCEDURE REGARDING NOMINATIONS AND SECONDING SPEECHES FOR THE CANDIDATES FOR THESE OFFICES DURING THE JOINT SESSION.
The Concurrent Resolution was adopted, ordered sent to the House.
H. 4605 (Word version) -- Rep. Huggins: A CONCURRENT RESOLUTION TO DECLARE TUESDAY, MARCH 2, 2010, SOUTH CAROLINA REALTOR DAY IN ORDER TO RECOGNIZE AND HONOR THE MANY OUTSTANDING REALTORS AND REAL ESTATE PROFESSIONALS IN OUR STATE.
The Concurrent Resolution was adopted, ordered returned to the House.
CARRIED OVER
S. 1174 (Word version) -- Senators Leatherman, O'Dell and Setzler: A BILL TO AMEND SECTION 12-6-40, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO THE APPLICATION OF THE INTERNAL REVENUE CODE TO STATE INCOME TAX LAWS, SO AS TO UPDATE THE REFERENCE TO THE INTERNAL REVENUE CODE TO THE YEAR 2009; TO ADOPT THE PROVISIONS OF PUBLIC LAW 111-126 RELATING TO THE TIMING OF DEDUCTIONS FOR CHARITABLE CONTRIBUTIONS FOR HAITI RELIEF; TO AMEND SECTION 12-6-50, AS AMENDED, RELATING TO PROVISIONS OF THE INTERNAL REVENUE CODE NOT ADOPTED BY STATE LAW, SO AS TO ADD PROVISIONS TO THOSE NOT ADOPTED; TO AMEND SECTION 12-6-3910, AS AMENDED, RELATING TO ESTIMATED STATE INCOME PAYMENTS, SO AS TO ALLOW THE DEPARTMENT OF REVENUE TO WAIVE PENALTIES ON CORPORATE TAXPAYERS WHO CALCULATE SOUTH CAROLINA ESTIMATED TAX PAYMENTS BASED ON FEDERAL ESTIMATED TAX PERIODS THAT DO NOT CONFORM TO STATE LAW; AND TO AMEND ACT 110 OF 2007 AND ACT 16 OF 2009, RELATING TO MISCELLANEOUS REVENUE PROVISIONS AND CONFORMITY OF STATE INCOME TAX LAW TO THE INTERNAL REVENUE CODE, SO AS TO DELETE OBSOLETE PROVISIONS.
On motion of Senator O'DELL, the Bill was carried over.
H. 4174 (Word version) -- Reps. Harvin, Bales, Harrison, G.M. Smith and Wylie: A BILL TO AMEND SECTION 12-37-3150, AS AMENDED, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO DETERMINING WHEN A PARCEL OF REAL PROPERTY MUST BE APPRAISED AS A RESULT OF AN ASSESSABLE TRANSFER OF INTEREST, SO AS TO PROVIDE THAT A CONVEYANCE TO A TRUST DOES NOT CONSTITUTE AN ASSESSABLE TRANSFER OF INTEREST IN THE REAL PROPERTY IF THE SETTLOR OR SETTLOR'S SPOUSE CONVEYS THE PROPERTY TO A TRUST THE BENEFICIARIES OF WHICH ARE A CHILD OR CHILDREN OF THE SETTLOR OR THE SETTLOR'S SPOUSE AND TO PROVIDE THAT A CONVEYANCE BY DISTRIBUTION UNDER A WILL OR BY INTESTATE SUCCESSION DOES NOT CONSTITUTE AN ASSESSABLE TRANSFER OF INTEREST IN THE REAL PROPERTY IF THE DISTRIBUTEE IS A CHILD OR CHILDREN OF A DECEDENT AND THE DECEDENT DID NOT HAVE A SPOUSE AT THE DECEDENT'S DATE OF DEATH.
On motion of Senator MALLOY, the Bill was carried over.
H. 3841 (Word version)--Reps. Owens, Cooper, Skelton, Sottile, J.M. Neal, R.L. Brown, Simrill, Battle, Govan, Barfield, Gullick, Stavrinakis, Hutto, Jefferson, Umphlett, Daning, Kirsh, Knight, Williams, Merrill, Weeks, Whipper, Mack, G.M. Smith, Lowe, Clemmons, Gilliard, Sellers, Erickson, Willis, Wylie, Mitchell, Stewart, Gunn, Vick, Harrell and J.R. Smith: A BILL TO AMEND THE CODE OF LAWS OF SOUTH CAROLINA, 1976, BY ENACTING THE "TECHNICAL COLLEGE ADMINISTRATIVE EFFICIENCIES ACT OF 2009" TO REQUIRE THE STATE BOARD FOR TECHNICAL AND COMPREHENSIVE EDUCATION TO ESTABLISH A TIERED SYSTEM FOR CATEGORIZING TECHNICAL COLLEGES; BY ADDING SECTION 2-47-70, TO ALLOW TECHNICAL COLLEGES TO ENTER INTO ONE OR MORE LEASE AGREEMENTS; BY ADDING SECTION 6-1-137 TO ALLOW TECHNICAL COLLEGES TO BE A PART OF CERTAIN CONTRACTS MADE BY COUNTIES, MUNICIPALITIES, OR SCHOOL DISTRICTS; TO AMEND SECTION 2-47-50, RELATING TO THE ESTABLISHMENT OF PERMANENT IMPROVEMENT PROJECTS BY THE STATE BUDGET AND CONTROL BOARD, TO PROVIDE FOR THE ESTABLISHMENT AND AUTHORIZATION OF PERMANENT IMPROVEMENT PROJECTS, AND TO PROVIDE THAT A TECHNICAL COLLEGE MAY NOT ADVERTISE AND INTERVIEW FOR PROJECT ARCHITECTURAL AND ENGINEERING SERVICES WITHOUT PRIOR APPROVAL OF THE ARCHITECTURAL AND ENGINEERING PHASE OF A PERMANENT IMPROVEMENT PROJECT; TO AMEND SECTION 2-65-30, RELATING TO RECEIPT AND EXPENDITURE OF UNANTICIPATED FUNDS, TO EXCLUDE TECHNICAL COLLEGES FROM STATE BUDGET AND CONTROL BOARD REVIEW OF EXPENDITURE PROPOSALS; AND TO AMEND SECTION 8-11-35, RELATING TO SALARY PAYMENT SCHEDULES, TO PROVIDE THAT THE STATE BOARD FOR TECHNICAL AND COMPREHENSIVE EDUCATION MAY APPROVE ALTERNATIVE SALARY PAYMENT SCHEDULES FOR TECHNICAL COLLEGE EMPLOYEES. (ABBREVIATED TITLE)
On motion of Senator BRYANT, the Bill was carried over.
THE CALL OF THE UNCONTESTED CALENDAR HAVING BEEN COMPLETED, THE SENATE PROCEEDED TO THE MOTION PERIOD.
RECALLED
S. 2 (Word version) -- Senators McConnell, Peeler, Leatherman, Sheheen, Rose, Courson, Elliott, Massey, Hayes, Davis, Bright and L. Martin: A BILL TO AMEND SECTION 11-11-410, CODE OF LAWS OF SOUTH CAROLINA, 1976, RELATING TO IMPLEMENTATION OF THE LIMIT ON STATE SPENDING IMPOSED PURSUANT TO SECTION 7(C), ARTICLE X OF THE CONSTITUTION OF SOUTH CAROLINA, 1895, SO AS TO REVISE THIS LIMIT BY IMPOSING AN ANNUAL LIMIT ON THE APPROPRIATION OF STATE GENERAL FUND REVENUES BY ADJUSTING SUCH REVENUES BY A ROLLING TEN-YEAR AVERAGE IN ANNUAL CHANGES IN GENERAL FUND REVENUES AND THE CREATION OF A SEPARATE BUDGET STABILIZATION FUND IN THE STATE TREASURY TO WHICH MUST BE CREDITED ALL GENERAL FUND REVENUES IN EXCESS OF THE ANNUAL LIMIT, THE REVENUES OF WHICH MUCH FIRST BE USED TO STABILIZE GENERAL FUND REVENUES AVAILABLE FOR APPROPRIATION, TO DEFINE EMERGENCIES AND TO PROVIDE FOR SUSPENSION OF THIS APPROPRIATIONS LIMIT IN EMERGENCIES, TO PROVIDE THAT A CASH BALANCE IN THE BUDGET STABILIZATION FUND IN EXCESS OF FIFTEEN PERCENT OF GENERAL FUND REVENUES OF THE MOST RECENT COMPLETED FISCAL YEAR MAY BE APPROPRIATED IN SEPARATE LEGISLATION FOR VARIOUS NONRECURRING PURPOSES, AND TO DEFINE SURPLUS GENERAL FUND REVENUES.
Senator LEATHERMAN asked unanimous consent to make a motion to recall the Bill from the Committee on Finance.
The Bill was recalled from the Committee on Finance and ordered placed on the Calendar for consideration tomorrow.
On motion of Senator LARRY MARTIN, the Senate agreed to dispense with the Motion Period.
HAVING DISPENSED WITH THE MOTION PERIOD, THE SENATE PROCEEDED TO A CONSIDERATION OF VETOES.
Message from the House
Columbia, S.C., March 3, 2010
Mr. President and Senators:
The House respectfully informs your Honorable Body that it has overridden the veto by the Governor on R130, H. 3624 by a vote of 4 to 1:
(R130, H3624 (Word version)) -- Reps. A.D. Young, Horne, Knight and Harrell: AN ACT TO PROVIDE THAT EACH MEMBER OF THE DORCHESTER COUNTY TRANSPORTATION COMMITTEE IS ALLOWED AND MUST BE PAID FROM DORCHESTER COUNTY "C" FUND REVENUES SEVENTY-FIVE DOLLARS FOR EACH MEETING AT WHICH THE MEMBER IS IN ATTENDANCE.
Very respectfully,
Speaker of the House
Ordered placed on the Calendar for consideration tomorrow.
VETO OVERRIDDEN
(R130, H3624 (Word version)) -- Reps. A.D. Young, Horne, Knight and Harrell: AN ACT TO PROVIDE THAT EACH MEMBER OF THE DORCHESTER COUNTY TRANSPORTATION COMMITTEE IS ALLOWED AND MUST BE PAID FROM DORCHESTER COUNTY "C" FUND REVENUES SEVENTY-FIVE DOLLARS FOR EACH MEETING AT WHICH THE MEMBER IS IN ATTENDANCE.
The veto of the Governor was taken up for immediate consideration.
Senator ROSE moved that the veto of the Governor be overridden.
The question was put, "Shall the Act become law, the veto of the Governor to the contrary notwithstanding?"
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 3; Nays 0
AYES
Grooms Matthews Rose
Total--3
NAYS
Total--0
The necessary two-thirds vote having been received, the veto of the Governor was overridden, and a message was sent to the House accordingly.
THE SENATE PROCEEDED TO A CONSIDERATION OF BILLS AND RESOLUTIONS RETURNED FROM THE HOUSE.
HOUSE AMENDMENTS AMENDED
RETURNED TO THE HOUSE WITH AMENDMENTS
S. 328 (Word version) -- Senators Verdin, Grooms, Cromer, Campbell, Bright, Bryant and Campsen: A BILL TO AMEND SECTION 47-5-60 OF THE 1976 CODE, RELATING TO INOCULATING PETS AGAINST RABIES, SO AS TO PROVIDE THAT THESE INOCULATIONS MUST BE ADMINISTERED BY A LICENSED VETERINARIAN OR SOMEONE UNDER THE DIRECT SUPERVISION OF A LICENSED VETERINARIAN.
The House returned the Bill with amendments.
The Senate proceeded to a consideration of the Bill, the question being concurrence in the House amendments.
Senator VERDIN proposed the following amendment (328R001.DBV), which was adopted:
Amend the bill, as and if amended, by striking all after the enacting words and inserting:
/ SECTION 1. Section 47-5-60 of the 1976 Code is amended to read:
SECTION 2. This act takes effect upon approval by the Governor. /
Renumber sections to conform.
Amend title to conform.
Senator VERDIN explained the amendment.
There being no further amendments, the Bill was ordered returned to the House with amendments.
Recorded Vote
Senators McCONNELL, CAMPSEN, SHANE MARTIN, MASSEY and BRIGHT desired to be recorded as voting against the adoption of the amendment.
Statement by Senators McCONNELL, SHANE MARTIN CAMPSEN and BRIGHT
We voted against the amendment because we agreed with the House version that eliminated the government setting the costs that could be charged for a rabies shot. The Senate amendment would mandate that veterinarians could not charge more than \$10. We firmly believe that charges for goods and services should be subject to the free market. In a choice between the free market and government price control, we believe that the free market should be victorious. Fortunately, the House amendment recognized that. Unfortunately, the Senate amendment did not. For that reason, we voted against this amendment which reestablished price controls.
THE SENATE PROCEEDED TO THE SPECIAL ORDERS.
DEBATE INTERRUPTED
H. 3305 (Word version) -- Reps. Bedingfield, Merrill, Bingham, Duncan, Loftis, G.R. Smith, Cato, Owens, Crawford, A.D. Young, Nanney, Bannister, Daning, Harrison, Horne, Kirsh, Lowe, Lucas, E.H. Pitts, Stringer, Thompson, Toole, Wylie, T.R. Young, Long, Rice, Parker, Allison, Littlejohn, Cole, Hiott, Edge, Whitmire, Hearn, Hardwick, D.C. Smith, Pinson, J.R. Smith, Simrill, Brantley, Willis, Hamilton, Erickson, Sottile, Scott, Harrell, Delleney, Gullick, Frye, Clemmons, G.M. Smith, Battle, Sandifer, Millwood, Haley, Ballentine, M.A. Pitts, Cooper, White, Gambrell, Bowen, Umphlett, Forrester, Barfield, Chalk, Herbkersman, Viers, Spires, Huggins, Limehouse, Stewart, Kelly, Brady and D.C. Moss: A JOINT RESOLUTION TO PROPOSE AN AMENDMENT TO ARTICLE II OF THE CONSTITUTION OF SOUTH CAROLINA, 1895, RELATING TO THE RIGHT OF SUFFRAGE, BY ADDING SECTION 12 SO AS TO GUARANTEE THE RIGHT OF AN INDIVIDUAL TO VOTE BY SECRET BALLOT FOR A DESIGNATION, A SELECTION, OR AN AUTHORIZATION FOR EMPLOYEE REPRESENTATION BY A LABOR ORGANIZATION.
The Senate proceeded to a consideration of the Joint Resolution, the question being the third reading of the Joint Resolution.
Senator HUTTO spoke on the Joint Resolution.
PRESIDENT Pro Tempore PRESIDES
At 2:29 P.M., Senator McCONNELL assumed the Chair.
Senator HUTTO spoke on the Joint Resolution.
Point of Quorum
At 3:27 P.M., Senator SETZLER made the point that a quorum was not present. It was ascertained that a quorum was not present.
Call of the Senate
Senator LARRY MARTIN moved that a Call of the Senate be made. The following Senators answered the Call:
Alexander Anderson Bright
Bryant Campbell Campsen
Cleary Coleman Courson
Cromer Davis Elliott
Fair Ford Grooms
Hayes Hutto Jackson
Knotts Land Leatherman
Leventis Lourie Malloy
Martin, Larry Martin, Shane Massey
Matthews McConnell McGill
Mulvaney Nicholson O'Dell
Peeler Pinckney Rankin
Reese Rose Ryberg
Scott Setzler Thomas
Verdin Williams
A quorum being present, the Senate resumed.
Senator HUTTO resumed speaking on the Joint Resolution.
Motion Under Rule 15A Failed
At 3:53 P.M., Senator LARRY MARTIN moved under the provisions of Rule 15A to vote on the entire matter of H. 3005.
The "ayes" and "nays" were demanded and taken, resulting as follows:
Ayes 23; Nays 19
AYES
Alexander Bright Bryant
Campbell Campsen Cleary
Courson Cromer Davis
Fair Grooms Hayes
Leatherman Martin, Larry Martin, Shane
Massey McConnell Mulvaney
O'Dell Peeler Rose
Thomas Verdin
Total--23
NAYS
Anderson Elliott Ford
Hutto Jackson Knotts
Land Leventis Lourie
Malloy Matthews McGill
Nicholson Pinckney Rankin
Reese Ryberg Setzler
Williams
Total--19
Having failed to receive the necessary vote, the motion under Rule 15A failed.
Senator HUTTO resumed speaking against the Joint Resolution.
Point of Quorum
At 4:15 P.M., Senator SETZLER made the point that a quorum was not present. It was ascertained that a quorum was not present.
Call of the Senate
Senator PEELER moved that a Call of the Senate be made. The following Senators answered the Call:
Alexander Anderson Bright
Bryant Campbell Campsen
Cleary Coleman Cromer
Davis Elliott Ford
Grooms Hutto Jackson
Knotts Land Leatherman
Leventis Lourie Malloy
Martin, Larry Martin, Shane Massey
Matthews McConnell McGill
Mulvaney Nicholson O'Dell
Peeler Rankin Reese
Rose Ryberg Scott
Setzler Thomas Verdin
Williams
A quorum being present, the Senate resumed.
Recorded Presence
Senators FAIR and PINCKNEY recorded their presence subsequent to the Call of the Senate.
Senator HUTTO argued contra to the third reading of the Resolution.
Objection
With Senator HUTTO retaining the floor, Senator LARRY MARTIN asked unanimous consent to make a motion that the Senate stand adjourned.
Senator BRIGHT objected.
Senator HUTTO argued contra to the third reading of the Resolution.
On motion of Senator HUTTO, debate was interrupted by adjournment.
On motion of Senator LARRY MARTIN, with unanimous consent, the Senate stood adjourned out of respect to the memory of Mr. Wayne Williams, 90 years old. A highly respected, lifelong resident of the Dacusville Community in Pickens County, he was a retired rural mail carrier and businessman, who was blessed with a wonderful family. Mr. Williams died on Sunday, March 7, 2010.
and
On motion of Senator PINCKNEY, with unanimous consent, the Senate stood adjourned out of respect to the memory of the Honorable Albert Lloyd Kleckley, Sr. of Okatie, S.C., beloved husband, devoted father, judge, friend and former colleague, having served in the House of Representatives from 1973-1976.
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