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Airborne Pollens and Symptoms Score in Allergic Patients Undergoing Immunotherapy | In the last years standardized monitoring techniques offered means to obtain pollen calendars (1,2). | In estimating the state of thrusting/ballistic endoatmospheric projectiles for the end purpose of impact point ::: prediction (IPP), the total observation time, the wind effect and the sensor accuracy significantly affect the IPP ::: performance. First the tracker accounting for the wind effect is presented. Following this, based on the multiple ::: interacting multiple model (MIMM) estimator developed recently, a sensitivity study of the IPP performance with ::: respect to the total observation time, the wind (strength and direction) and the sensor accuracy is presented. | eng_Latn | 51,425 |
Grey Prediction of Port Throughput Based on GM(1,1,α) Model | According to the situation of lack of statistical data, this paper makes use of the time sequence prediction theory of nonlinear grey GM(1,1,α) Model to predict the port throughput based on the data of LianYungang port throughput from 2003 to 2007, and expounds the application of nonlinear grey forecasting method. Results show that the nonlinear grey GM(1,1,α) model can prediction of adaptability, high precision, simple, and can effectively solve the port throughput prediction problem. | The navigation condition of tributaries at TGP reservoir area has improved essentially but it still lacks navigation grading standard,for the normal grading standard of inland river takes no consideration of the effect of reservoir on the tributary channel navigation.So the normal grading standard can't be applied to determine the technical grade of tributary channel.Taking Meixi River as the typical tributary,the preliminary exploration of grading the tributaries navigation technically after the accomplishment of TGP reservoir is carried out;the exploration is discussed from various aspects,such as flow condition,channel dimension and the navigation guarantee rate.The proposed standard is applied to Meixi River,and its channel navigation standard after the accomplishment of TGP is obtained,which can be taken as the reference for the navigation grading study of TGP reservoir and navigation tributaries of similar reservoirs. | eng_Latn | 51,463 |
Crop planning in relation to climate change in rain fed regions. | Uncertainty and variability of rains both space and time is the major constraints affecting agricultural production in rain fed farming. Scientific study on the quantum and distribution of rainfall ... | This paper will discuss our approach to convert these images into application maps (i.e. shape files) without much effort or special knowledge from the pilot/operator, which could then be a new service to a customer. These application maps could then be easily uploaded into the spray system computer to make variable-rate aerial application such as cotton growth regulators, defoliants, and insecticides. The goal of these research projects is to demonstrate that precision agriculture technology has the potential to benefit the industry by saving operators and farmers’ time and money. | eng_Latn | 51,465 |
Spatial Regression-Based Environmental Analysis in Infectious Disease Informatics | Studying relationships between environmental factors and infectious diseases is an important topic in public health research. The existing studies have been focused on temporal correlations among environmental risks and infectious disease outbreaks. In this paper, we advocate the importance of spatial data analysis in infectious disease-related environmental analysis. Using data from the Beijing CDC, we have conducted spatial regression analysis to study correlation between Measles occurrences and the following environmental factors: population density and proximities to railways, roads, and water systems. We report some preliminary findings concerning significant spatial autocorrelation identified from our analysis. | Abstract This paper describes the philosophy, algorithms, and implementation of a computer simulation model for land use forecasting, and the capability of generating maps of these forecasts. The model is applicable to SMSA's organized on a census tract basis by counties. The forecasts are macro to the census tract level for industrial, residential, commercial and public land uses. Modeling is based on an economic data base of the region, and is extremely flexible for the user. An example set of forecasts and maps is included for illustrative purposes. | eng_Latn | 51,519 |
Experimental Studies on Hygrothermal Behaviour of ETICS | A preliminary test was carried out to assess where, in a facade, was surface condensation more severe: near the corners or in the middle of the wall. The test was performed on a building located in the University of Porto campus. Devices were set up on the North facade covered with ETICS of a technical building located close to the Building Physics Laboratory weather station, which collected the necessary climate data for this study. | In Section 1 several scenarios were selected that were based on instrumentally observed historical climatic data (HIST) and on results from a general circulation model (GISS). In this section we employ indices or models to analyze the impacts associated with these scenarios on the thermal climate (growing degree days), the moisture climate (precipitation effectiveness), the combined thermal-moisture effects (climatic index of agricultural potential which reflects biomass potential), and on drought frequency. | kor_Hang | 51,535 |
Using 4C seismic data to improve prospect appraisal : A case study from offshore Trinidad | There are many situations where OBC data can make a difference: Gas occlusion, fault shadows and shear wave splitting are some of the problems that were overcome on this project. | Abstract This paper describes the philosophy, algorithms, and implementation of a computer simulation model for land use forecasting, and the capability of generating maps of these forecasts. The model is applicable to SMSA's organized on a census tract basis by counties. The forecasts are macro to the census tract level for industrial, residential, commercial and public land uses. Modeling is based on an economic data base of the region, and is extremely flexible for the user. An example set of forecasts and maps is included for illustrative purposes. | eng_Latn | 51,536 |
Ordinal Regression Model for Forecasting En Route Controller Requirements | A model for forecasting enroute controller requirements was developed by Tien and Schonfeld [1] for incorporation into the FAA's NAS Strategy Simulator. In this study, one critical component in their work is improved by using probit regression model in order to more reasonably predict the number of controller positions per sector. Probabilities of using between 0 and 4 controllers per sector are estimated from the controller work history based on traffic densities and other sector characteristics. The improved controller estimation model is then demonstrated for its practicability and can provide an estimate of annual controller requirements in response to future traffic growth and capacity for evaluating future enroute performance. | Abstract There is a greater need than ever for the ability to accurately model urban system impacts resulting around the planet. Rapid urbanization is transforming landscapes from vegetation to an engineered infrastructure and thus altering land cover and land use. These alterations impact urban and global climate change, energy demand, human health, and ecological service functions. This article presents an overview of a refined land-cover classification protocol that seeks to refine current land-cover classifications of engineered paved surfaces. This new approach provides those who model urban systems and engineer the environment as well as other scientists and policy makers an expanded understanding of how intervention to the system can most effectively be accomplished through enhanced modeling. An object-oriented analysis regime is presented for an industrial park utilizing commercial software in conjunction with multispectral and panchromatic Quickbird satellite imagery. A detailed examination of ho... | eng_Latn | 51,538 |
Study on resembling simulation experiment of spontaneous combustion in goaf | To study the impact of different types of ventilation leakage on spontaneous combustion in goaf,and in accordance with the different states of ventilation leakage in goaf,the goaf is divided into different regions of the fire danger,in order to judge the location of spontaneous combustion in goaf.By developing the resembling simulation models,many experiments are carried out to research the spontaneous combustion in goaf.Then,the goaf ventilation pressure isoline and ventilation flow distribution are observed and drawn,which are also drawn after the air duct for gas releasing is placed in the upper corner of coal face and after the stowing strips are placed in goaf. | ABSTRACTWe utilize the Internet search data from Google Trends to provide short-term forecasts for the inflow of Japanese tourists to South Korea. We construct the Google variable in a systematic way by combining keywords to minimize mean squared or mean absolute forecasting errors. We augment the Google variable to the standard time-series forecasting models and compare their forecasting accuracies. We find that Google-augmented models perform much better than the standard time-series models in terms of short-term forecasting accuracy. In particular, Google models show better out-of-sample forecasting performance than in-sample forecasting. | eng_Latn | 51,539 |
Effective Learning Through Gaming Simulation Design | Recent education graduates and participants of the training course have also started to use gaming simulation in processes of organizational development of school administrations. Increasingly, more appropriate learning environments are constructed in the educational system, with a great potential to create effective learning processes and to advance educational social systems. In addition, the designed games of the training programs phase III deal with different social issues and in this way contribute to the development and preferred change of social systems and society itself. | Leveraging grid computing technology, i.e. the visualization of distributed computing and data resources such as processing, network bandwidth and storage capacity to create a single system image, we present a Grid Air Quality Forecast System (G-AQFS). The modeling system consists of meteorological and dispersion models coupled in cascade. The computational workflow of the modeling system is defined by means of DAGs (direct acyclic graph). A simple system is presented to manage and schedule the computational grid resources. As case study the system has been applied over Salento area, in the Apulia region (South-eastern Italy), to simulate ground level ozone concentration. Model predictions have been compared with field measurements, with reasonable results. | eng_Latn | 51,551 |
Deriving the Declining Areas and Analysing Their Spatial Characteristics Using the Spatial Autocorrelation Measure | This study aims to analyse the spatial characteristics and to draw the declining areas from the whole area of Chung-Cheong Province. For this purpose, the temporal and spatial conditions by the urban decline diagnosis indexes are utilized. Additionally, the spatial autocorrelation method was applied for extraction of those areas. The spatial autocorrelation method is one of the methods on exploring spatial characteristics and considering the spatial factors. We also adopted the concepts of economics and then discovered the characteristics of deprivation areas. In applying this method, the positively valued areas were classified as the complementary areas, and the negatively valued areas as the substitutional areas. The findings show the declining areas and the growing areas caused by the growth of periphery. This study supports the regeneration plan of Chung-Cheong Province in extracting depressed or activated areas and explaining the characteristics of those areas. | Abstract This paper describes the philosophy, algorithms, and implementation of a computer simulation model for land use forecasting, and the capability of generating maps of these forecasts. The model is applicable to SMSA's organized on a census tract basis by counties. The forecasts are macro to the census tract level for industrial, residential, commercial and public land uses. Modeling is based on an economic data base of the region, and is extremely flexible for the user. An example set of forecasts and maps is included for illustrative purposes. | eng_Latn | 51,561 |
Research of change detection using GIS auxiliary data and samples | Land use change detection is important in the study of the globalization in the world.The research of change detection using remote sensing images have made great progress.But the auto-detection method is still not practical because of the method of the image segment,the low degree of automation.This paper proposes a new method,which analyzes the images change in segments obtained from the GIS auxiliary data.The sample-auto-selection method and sample-auto-update method can reduce the human involvement.The experiment shows the effectiveness of the method. | Abstract This paper describes the philosophy, algorithms, and implementation of a computer simulation model for land use forecasting, and the capability of generating maps of these forecasts. The model is applicable to SMSA's organized on a census tract basis by counties. The forecasts are macro to the census tract level for industrial, residential, commercial and public land uses. Modeling is based on an economic data base of the region, and is extremely flexible for the user. An example set of forecasts and maps is included for illustrative purposes. | eng_Latn | 51,580 |
Looking for totals not averages. Ideally it would allow look up by zip code. | The best place would be to contact the National Weather Service for the area you are studying. They should have data on all weather patterns collected from weather stations all around the country. Some weather stations have only local data. \nYou could also check the weather almanac for the specific year you would like to research. You can usually find precip totals for every year that records have been kept. | Sure! Start with the templates available right inside your word processor, check the packaging from your labels. There may be a website to download from or even a mini-CD. Generic or custom sizes can be entered into websites such as avery, mead, daytimers, franklinplanners, etc., etc. | eng_Latn | 51,612 |
On the stability and causality of scalar-vector theories | Various extensions of standard inflationary models have been proposed recently by adding vector fields. Because they are generally motivated by large-scale anomalies, and the possibility of statistical anisotropy of primordial fluctuations, such models require to introduce non-standard couplings between vector fields on the one hand, and either gravity or scalar fields on the other hand. In this article, we study models involving a vector field coupled to a scalar field. We derive restrictive necessary conditions for these models to be both stable (Hamiltonian bounded by below) and causal (hyperbolic equations of motion). | Abstract: We study the pointwise behavior of the Fourier transform of the spectral measure for discrete one-dimensional Schrödinger operators with sparse potentials. We find a resonance structure which admits a physical interpretation in terms of a simple quasiclassical model. We also present an improved version of known results on the spectrum of such operators. | eng_Latn | 51,632 |
Group theoretical methods are used to study some properties of the Riccati equation, which is the only differential equation admitting a nonlinear superposition principle. The Wei–Norman method is applied to obtain the associated differential equation in the group SL(2, ℝ). The superposition principle for first order differential equation systems and Lie–Scheffers theorem are also analyzed from this group theoretical perspective. Finally, the theory is applied in the solution of second order differential equations like time independent Schrodinger equation. | The Wei-Norman formula locally relates the Magnus solution of a system of linear time-varying ODE with the solution expressed in terms of products of exponentials by means of a set of nonlinear differential equations in the parameters of the two types of solutions. A closed form expression of such formula is proposed, based only on the structure constants of the Lie algebra generated by the ODEs. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 51,679 |
In this paper, we discuss linear inference for the lifetime distribution of components based on a Type-II censored lifetime data of reliability systems with known signatures. We derive the best linear unbiased estimators (BLUE) for the parameter(s) in general scale and location-scale parameter families. The exact computational formulas of the BLUE and their variances and covariance are provided. Selected tables of the coefficients of BLUE are presented for the exponential and extreme value distributions. Using these, best linear unbiased predictors of future system failure times are discussed. Finally, two examples are provided to illustrate all the methods of inference developed here. | We introduce two new families of univariate distributions that we call hyperminimal and hypermaximal distributions. These families have interesting applications in the context of reliability theory in that they contain that of coherent system lifetime distributions. For these families, we obtain distributions, bounds, and moments. We also define the minimal and maximal signatures of a coherent system with exchangeable components which allow us to represent the system distribution as generalized mixtures (i.e., mixtures with possibly negative weights) of series and parallel systems. These results can also be applied to order statistics (k-out-of-n systems). Finally, we give some applications studying coherent systems with different multivariate exponential joint distributions. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 51,688 |
This article argues that direct ecological impact needs to be incorporated into research on organizations and the natural environment, as complementary to conceptualizations of ecological impact as a social construction. Building on work in analytical sociology, it proposes to study socio-ecological mechanisms and thus enhance the understanding of processes of organizing within dynamic ecosystems. Three categories of socio-ecological mechanisms are introduced and illustrated with examples. The article concludes with reflections on the expected increase of direct ecological impact on organizations. | Using in-depth ethnographic analysis of Kejetia’s artisanal gold mining community in Tongo (Northern Ghana), this article argues that governance is based on artisanal gold miners’ three-dimensional orientation towards both ‘above-ground’ social–political relations and regulations (a geometrically two-dimensional orientation) and the ‘subterranean’ geological sphere (which literally adds depth and a third geometric dimension). A substance relation to gold also means that its properties and geological context strongly influence miners’ micro governance, as do miners’ cosmological perceptions of gold’s relationship to the above-ground and subterranean spheres. Hence, gold acquisition is embedded in a web of geological, social and cosmological relations beyond actual excavation. Artisanal mining policy and research should recognise the impact of this three-dimensional orientation and substance approach. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 51,693 |
We speculate on the role of relativistic versions of delayed differential equations in fundamental physics. Relativistic invariance implies that we must consider both advanced and retarded terms in the equations, so we refer to them as shifted equations. The shifted Dirac equation has some novel properties. A tentative formulation of shifted Einstein-Maxwell equations naturally incorporates a small but nonzero cosmological constant. | In this paper we introduce and investigate a new kind of functional (including ordinary and evolutionary partial) differential equations. The main goal of this paper is to explore our new philosophy by some examples on functional ODEs and PDEs. For some typical examples, we prove the global existence of smooth solutions, analyze some interesting properties enjoyed by these solutions, and illustrate the differences between this new class of equations and the traditional ones. This kind of functional differential equations is a new and powerful tool to study some problems arising from both mathematics and physics, more applications in particular to differential geometry and fundamental physics can be expected. | We characterize stability under composition, inversion, and solution of ordinary differential equations for ultradifferentiable classes, and prove that all these stability properties are equivalent. | eng_Latn | 51,705 |
Strength of the null singularity inside black holes | We study analytically the Cauchy horizon singularity inside spherically symmetric charged black holes, coupled to a spherical, self-gravitating, minimally coupled, massless scalar field. We show that all causal geodesics terminate at the Cauchy horizon at a null singularity, which is weak according to the Tipler classification. The singularity is also deformationally weak in the sense of Ori. Our results are valid at arbitrary points along the null singularity, in particular at late retarded times, when nonlinear effects are crucial. | We give a detailed discussion of the construction of the Batalin-Vilkovisky BRST charge for the heterotic superstring. In particular, we completely solve the higher-ghost sector using a recursion relation. The gauge choice ▽+θ = 0, which we previously proposed for the superparticle, leads to a free quantum action. | eng_Latn | 51,713 |
Effects of space charge in beams for heavy ion fusion | A new analytic model is presented that accurately estimates the radially averaged axial component of the space-charge field of an axisymmetric heavy-ion beam in a cylindrical beam pipe. The model recovers details of the field near the beam ends that are overlooked by simpler models, and the results compare well to exact solutions of Poisson`s equation. Field values are shown for several simple beam profiles and are compared with values obtained from simpler models. The model has been implemented in the fluid/envelope code CIRCE and used to study longitudinal confinement in beams with a variety of axial profiles. The effects of errors in the longitudinal-control fields are presented. | Spherically symmetric solutions in Brans-Dicke theory of relativity with zero coupling constant, $\omega=0$, are derived in the Schwarzschild line-element. The solutions are obtained from a cubic transition equation with one small parameter. The exterior space-time of one family of solutions is arbitrarily close to the exterior Schwarzschild space-time. These nontopological solitons have some similarity with soliton stars, and are proposed as candidates for {\em approximate black holes} for the use in numerical relativity, in particular for treatment of horizon boundary conditions. | eng_Latn | 51,720 |
Note on the point-splitting procedure to evaluate vacuum fluctuation in certain cylindrically symmetric backgrounds | We reexamine the two-point function approaches used to study vacuum fluctuation in wedge-shaped regions and conical backgrounds. The appearance of divergent integrals is discussed and circumvented. The issue is considered in the context of a massless scalar field in cosmic string spacetime. | Abstract In this work, we study the analyticity of Kuramoto–Sivashinsky type equations and related systems by exploring the applicability of the semigroup method, which was developed in Collet et al. [5] . We establish the analyticity, with respect to the spatial variable in a strip around the real axis, for a variety of dissipative–dispersive systems, which possess universal attractors. We also provide lower bounds for the width of the strip of analyticity. | eng_Latn | 51,729 |
Experimental investigation of resonantly forced oscillations of a two-degree-of-freedom structure | Abstract An experimental study of the response of a two-degree-of-freedom structure with quadratic non-linearities and a two-to-one internal resonance to an external harmonic excitation is presented. When the excitation frequency was close to the lower natural frequency of the structure, periodic, quasi-periodic, and chaotic responses were observed. Fourier spectra, time-dependent modal decompositions, and Poincare maps were used to analyze the amplitude- and phase-modulated motions of the structure. | We derive asymptote solution of a homogeneous and isotropic universe governed by the quadratic form of the field equation of $f(T)$ gravity. We explain how the higher order of the torsion can provide an origin for late accelerated phase of the universe in the FRW. The solution makes the scalar torsion $T$ to be a function of the cosmic time $t$. We show that for the equation of state $p=\omega \rho$ with $\omega\neq -1$ the scale factor represent late phase of universe. We perform the cosmological studies and show how the quadratic form of $f(T)$ effect on the behavior of these studies. | eng_Latn | 51,736 |
Free boundary skin current magnetohydrodynamic equilibria | Function theoretic methods in the complex plane are used to develop simple parametric hodograph formulas that generate sharp boundary equilibria of arbitrary shape. The related method of Gorenflo [Z. Angew. Math. Phys. 16, 279 (1965)] and Merkel (Ph.D. thesis, University of Munich, 1965) is discussed. A numerical technique for the construction of solutions, based on one of the methods, is presented. A study is made of the bifurcations of an equilibrium of general form. | In the footsteps of our previous work \cite{RamatonBoschi} we generalize the Stefan-Boltzmann and Wien's displacement laws for the $ \textrm{AdS}_5 \times {\cal S}^5 $ spacetime, the background of the AdS/CFT correspondence foremost realization. Our results take into account the $ \textrm{AdS}_5 \times {\cal S}^5 $ full dimensionality in the electromagnetic field $A^{\mu}$ wave equation, which yields the higher-dimensional blackbody characteristic features suggested in literature. In particular, the total radiated power and the spectral radiancy match the original Stefan-Boltzmann and Wien's displacement laws in the low-energy regime up to available experimental data. | eng_Latn | 51,738 |
The numerical research of runner cavitation effects on spiral vortex rope in draft tube of Francis turbine | The spiral cavitating vortex rope developed in the draft tube of Francis turbine under part load condition maybe causes serious pressure fluctuations and power swings, which threatens the safety and stability of the power plant operations. Many works have been performed to explore the mechanisms of it. In this paper, the runner cavitation and spiral vortex rope under part load conditions were studied to investigate the relations of runner cavitation and the spiral vortex rope. The results proved the existence of obvious interaction between them. The swirl flow at the runner outlet plays an important role in the formation of vortex rope. And the periodic procession of vortex rope in turn intensifies the uneven pressure distribution near the runner outlet and causes the asymmetric cavitation on the runner blades, which then give rise to the modification of swirl flow at the runner blades and thereby affects the characteristics of vortex rope. | In this paper we consider torsion gravity in the case of the Dirac field, and by going into the rest frame we study what happens when a uniform precession as well as a phase are taken into account for the spinor field; we discuss how partially conserved axial-vector currents and torsion-spin attractive potentials justify negative Takabayashi angle and energy smaller than mass: because in this instance the module goes to zero exponentially fast then we obtain stable and localized matter distributions suitable to be regarded as a description of particles. | eng_Latn | 51,744 |
Lattice study of classical inflaton decay | We study numerically the decay of the inflaton by solving the full nonlinear equations of motion on the lattice. We confirm that parametric resonance is effective in transferring energy from the inflaton to a scalar field as long as the self-interactions of the second field are very small. However, in the very broad resonance case $(q\ensuremath{\gg}1)$ the decay rate is limited by scatterings, which significantly slows down the decay. We also find that the inflaton cannot decay via parametric resonance into a scalar field with moderate self-interactions. This means that the preheating stage may be completely absent in many natural inflationary models. | In this paper, we consider the density-dependent incompressible Navier–Stokes equations in with linearly growing initial velocity at infinity. We obtain a blow-up criterion and global well-posedness of the two-dimensional system. It generalized the local well-posedness results due to the recent work by the first and third authors to the global well-posedness in . Copyright © 2012 John Wiley & Sons, Ltd. | eng_Latn | 51,750 |
Curvature estimates for immersed hypersurfaces in Riemannian manifolds | We establish mean curvature estimate for immersed hypersurface with nonnegative extrinsic scalar curvature in Riemannian manifold $(N^{n+1}, \bar g)$ through regularity study of a degenerate fully nonlinear curvature equation in general Riemannian manifold. The estimate has a direct consequence for the Weyl isometric embedding problem of $(\mathbb S^2, g)$ in $3$-dimensional warped product space $(N^3, \bar g)$. We also discuss isometric embedding problem in spaces with horizon in general relativity, like the Anti-de Sitter-Schwarzschild manifolds and the Reissner-Nordstr\"om manifolds. | Abstract In this note, we obtain some results for the Riccati differential equations u′=A(z)+u2 with nonentire meromorphic functions A(z). Some examples are given to illustrate our some results are sharp. | eng_Latn | 51,754 |
TUW-92-04 UWThPh-1992-17 Novel Symmetry of Non-Einsteinian Gravity in Two Dimensions | The integrability of R2‐gravity with torsion in two dimensions is traced to an ultralocal dynamical symmetry of constraints and momenta in Hamiltonian phase space. It may be interpreted as a quadratically deformed iso(2,1)‐algebra with the deformation consisting of the Casimir operators of the undeformed algebra. The locally conserved quantity encountered in the explicit solution is identified as an element of the center of this algebra. Specific contractions of the algebra are related to specific limits of the explicit solutions of this model. | Abstract In this work, we study the analyticity of Kuramoto–Sivashinsky type equations and related systems by exploring the applicability of the semigroup method, which was developed in Collet et al. [5] . We establish the analyticity, with respect to the spatial variable in a strip around the real axis, for a variety of dissipative–dispersive systems, which possess universal attractors. We also provide lower bounds for the width of the strip of analyticity. | yue_Hant | 51,766 |
Laser Shock Adhesion Test (LASAT) of composite materials for aerospace industry | A study of composite material damage induced by laser shock waves | Three-dimensional finite element analysis of double-lap composite adhesive bonded joint using submodeling approach | eng_Latn | 51,894 |
Design Of Partially Prestressed Concrete Beam-Column Connection With Singly PrestressedSections Under Cyclic Loadings | Prestressed Concrete framed structure are commonly designed to provide presstressing steel to resist gravity loads. Therefore most of the prestressing tendons are located at the top of the beam at beam-column connections. Experimental and numerical non-linear finite element studies developed by the author show that these types of structures are capable to resist severe cyclic loading provided sufficient care is given. Special attention must be considered in the limitation of ductility demand, partial prestressing ratio and detailings in the potential plastic hinge regions. In this paper a simple and semi-rational design method for partially-prestressed interior beam-column connection in proposed. As the behavior of connections are non-flexural, the design method developed is based on major and minor strut modeling using plasticity theory. | The paper introducess the implemented conditions which colling recycle of flexible base on Ying-DaLine.It over all xpounds the investigation of road condlitions of original pavement,indoor trial study,determination of trial lot plan as well as completion of trial lot etc. | eng_Latn | 51,942 |
An attempt to explain strength increase due to high loading rates | Abstract Most materials such as steel, concrete, ceramics, polymers, etc. show an increase of strength due to high loading rates. A number of mathematical equations are available to describe this behaviour. Nevertheless the physical reasons for these observations are still unknown. The common behaviour of a number of materials leads to the assumption that at least some explanations are material independent. Due to this reason the results of the research done at the Institute for Concrete Structures in Karlsruhe are presented in this paper to furnish new ideas for the material research due to dynamic loading. | A study of the factors which affect the fold kinematic activities has been presented,through the design analysis,the sensitivity of acceleration vs.design was obtained.According to the sensitivity,the lengths of linkage and crank were determined as design variables.The optimization technique was applied to an ADAMS Model so as to minimize the value of acceleration.The result showed that the value of jerk was also improved while the value of acceleration was optimizing.It will improve the vibration properties and be the foundation of dynamics simulation later on. | eng_Latn | 51,946 |
Design for missile test system based on VI | A large amount of data acquisition,storage and analysis should be carried out during the research for some type of missile.Constructing a test system consisting of VI can greatly simplify the design,reduce the volume and weight,shorten the research interval and acquire a good flexibility.This paper introduces a general-purpose test platform for missile based on PXI bus and NI Series cards.It can acquire and test the data from analog,digital,bus and image channels and can communicate with the tested products.The test system has already been put into operation,which has features of appropriate design,reliable performance,accurate testing,convenient operation and satisfied results. | Abstract: Road profile and the technical condition of the suspension affect a large measure of comfort, road safety and endurance. This paper contains the theoretical study results of the offroad vehicle vibration when running on a bumpy section of road. For this purpose has been developed mechanical model of tire-suspension -self supporting bodyshell system with five degrees of freedom. The bodyshell was approximated by a flat plate, suspension and tires were modelled by four mass-damper-spring system attached to the four corners of the plate; the tire mass together with a mass suspension is concentrated at a single point. Vertical vibration displacement, velocity and acceleration of the body were determined using Matlab. Key words: vehicle vibration, vehicle mechanical modelling, road deformation. | eng_Latn | 51,959 |
A novel timber dowel-type connection using shape memory alloy | In order to provide self-centering effect, a novel timber dowel-type connection system using superelastic shape memory alloy (SMA) bar and tubes as dowels is investigated in this study. Double-shear connections with SMA and mild steel dowels were tested under dynamic loadings at different displacement levels. The results showed that SMA dowel-type connections have good self-centering behaviours and can mitigate the residual deformation effectively compared with steel dowel-type connections after excessive deformation, although the steel dowel-type connections present higher strength. These tests reveal that the connection with tube dowels show higher equivalent viscous damping ratio than those use solid bar as tube would allow larger deformation to dissipate energy. | The article discusses the question of development of software for automated design of road wooden bridge spans. The adaptive pattern of elastic load distribution calculation based on obtained loading theorem providing optimal geometry elements choice is developed. It is given a comparison of the measured real spans deflection with the results of calculating using two methods. | eng_Latn | 51,966 |
The durability of reinforced concrete bridge | This paper introduces the actual provision about road bridge criterion controling durability,and some new methods to improve reinforced concrete bridge durability. | The paper introducess the implemented conditions which colling recycle of flexible base on Ying-DaLine.It over all xpounds the investigation of road condlitions of original pavement,indoor trial study,determination of trial lot plan as well as completion of trial lot etc. | eng_Latn | 51,967 |
Bursting problem of filament wound composite pressure vessels | Using the nonlinear finite element method, we have calculated the stresses and the bursting pressure of filament wound solid-rocket motor cases which are a kind of composite pressure vessel. Maximum stress failure criteria and a stiffness-degradation model were introduced to the failure analysis. The effects of material performance and geometrical nonlinearity on the relative loading capacity of the dome were studied. For the model I case with skirts, relative loading capacity of the dome increased when geometrical nonlinearity was considered and composite material of higher strength was used. But for the model II case without skirts, the conclusion obtained was contrary to that for the model I case. | Introduction ::: The purpose of this study is to compare the tissue incorporation of a novel fenestrated and non-fenestrated crosslinked porcine dermal matrix (CPDM) (CollaMend™, Davol Inc., Warwick, RI) in a porcine model of ventral hernia repair. | eng_Latn | 51,973 |
Effects of lesions of thalamic intralaminar and midline nuclei and internal medullary lamina on spatial memory and object discrimination. | Male Sprague-Dawley rats received either radiofrequency lesions of the lateral internal medullary lamina (IML) or ibotenic acid lesions of the lateral intralaminar nuclei (ILN) and midline nuclei (MLN) or sham treatment. Neither lesion group was impaired in the retention of 3 object pair discriminations acquired before surgery nor in the acquisition of a new object pair after surgery. Rats with ILN, but not IML, lesions were impaired in acquiring an initial and 5 subsequent hidden platform locations in a water maze task. These results suggest that damage to both ILN and MLN are needed to produce spatial learning deficits and that extensive damage to the IML or ILN has no detectable effects on retrograde or anterograde memory of object discriminations. | Most currently available material models for composites do not allow for permanent strain. For applications such as ballistic containment and energy absorption applications, this results in under predicting material performance. This study extends the Matzenmiller, Lubliner and Taylor (MLT) model, a continuum damage mechanics (CDM) based constitutive model for unidirectional composites, to 3D solid elements, and enhances it with permanent strain capability. The model was implemented into the commercially available finite element code LS-Dyna. The model was validated with 3-point bend experiment. It was then used to simulate ballistic impact tests of an aluminum projectile against a glass fiber composite plate. As shown in the results below, this provides significant improvement in prediction of material performance | eng_Latn | 51,978 |
On the role of strain and stress state in ductile failure | Abstract U sing plane strain and axisymmetric notched tensile specimens in combination with finite deformation stress analysis, the strain to initiate failure in a range of structural steels is shown to be co-related by the state of stress for both axisymmetric and plane states of strain. The implications of this result for ductile failure terminated by flow localisation is discussed in the light of the theoretical work on localised flow. | In the light of the situation that there are no provisions about fatigue load in the highway bridge design codes and specifications in China for the time being,this paper conducts a study of the determination method and principle of fatigue test load for the cable and girder anchorage structure of highway steel cable-stayed bridge,using the specifications abroad and fatigue cumulative damage theories,on the basis of the vehicle load statistic data collected in some cities and on some sections of the National Roads in the country,and also with reference to the traffic volume prediction in the feasibility study of Sutong Bridge and other relevant highway engineering technical standards. | eng_Latn | 51,981 |
A coupled analysis of mechanical behaviour and ageing for polymer-matrix composites | The use of organic-matrix composites for long lifetime aeronautics applications leads to a study of the coupling effects between thermo-mechanical stresses and thermal ageing. Taking into account the effects of oxidation in a behaviour law requires first, an understanding of every mechanism of degradation and the interactions between them. The objective of this paper is to present current studies of these subjects and, in particular, our own approach, in order to include oxidation in a macroscopic behaviour law. For the oxidation section, studies have led to establishment of kinetics of thermal-oxidation for several polymer matrixes. For the mechanical section, a visco-elastic model coupled with damage is presented and allows to obtain the multiaxial creep behaviour of any composite laminate from few short-time tests conducted on elementary laminates. | A robust algorithm for computing reduced-order models of parametric systems is proposed. Theoretical considerations suggest that our algorithm is more robust than previous algorithms based on explicit multi-moment matching. Moreover, numerical simulation results show that the proposed algorithm yields more accurate approximations than traditional non-parametric model reduction methods and parametric model reduction methods based on explicitly computing moments. Copyright line will be provided by the publisher | eng_Latn | 51,985 |
Experimental Characterization of Mechanical Behavior of Cord‐Rubber Composites | Abstract Unidirectional cord‐rubber specimens in the form of tensile coupons and sandwich beams were used. Using specimens with the cords oriented at 0°, 45°, and 90° to the loading direction and appropriate data reduction, we were able to obtain complete characterization for the in‐plane stress‐strain response of single‐ply, unidirectional cord‐rubber composites. All strains were measured by means of liquid mercury strain gages, for which the nonlinear strain response characteristic was obtained by calibration. Stress‐strain data were obtained for the cases of both cord tension and cord compression. Materials investigated were aramid‐rubber, polyester‐rubber, and steel‐rubber. | The paper introducess the implemented conditions which colling recycle of flexible base on Ying-DaLine.It over all xpounds the investigation of road condlitions of original pavement,indoor trial study,determination of trial lot plan as well as completion of trial lot etc. | eng_Latn | 51,987 |
Nanotribology: Nonlinear Mechanisms of Friction | Friction with its related nonlinear dynamics is a vast interdisciplinary field, involving complex physical processes over a wide range of length and time scales. The accelerated progress in experimental and computational techniques, often leading to complex detailed dynamical patterns, has vigorously stimulated the search and implementation of idealized experimental frameworks and simpler mathematical models, capable of describing and interpreting, in a more immediate way, the essential physics involved in nonlinear sliding phenomena. | Due to economic growth, the number of cars has grown rapidly and consequently traffic accidents have grown in direct ratio. This reminds us that braking device of a vehicle is an important factor to prevent traffic accidents. Aim these researches to speed and lighten the braking system of vehicles, to lengthen its durability and to shorten the stopping distance. However, it is still difficult to analyze quantitatively and clearly the reason and solution for abnormal wear of disc and pad or judder in flywheel mode. Therefore this study was carried out to presume for mutual relation of analysis condition to get the optimum temperature by two-way layout. The results shown that coefficient of determination has a fine reliability over 92.57% and temperature is made by two-way layout. | eng_Latn | 51,994 |
BEHAVIOR OF BENDING AFTER LOW VELOCITY IMPACT AND QUASI-STATIC TRANSVERSE INDENTATION OF COMPOSITE HONEYCOMB CORE SANDWICH PANELS | Pure bending tests after low velocity impact and quasi static transverse indentation tests were carried out on composite Nomex honeycomb core sandwich panels. Methods of X ray, deply and visual inspection were used to measure the damage in specimens. Bending failure behavior was studied on the sandwich panels, in which the impacted face sheet was compressed and another face sheet tensioned. The damage caused by transverse indention was compared with that by low velocity impact. The damage and rules of contact force P against indent displacement Δ h were discussed at different transverse indent speeds. Results showed that the bending strength of honeycomb core sandwich panels was reduced extensively by low velocity impact and that the Nomex honeycomb core sandwich panels were not sensitive to transverse indent speed. | The paper introducess the implemented conditions which colling recycle of flexible base on Ying-DaLine.It over all xpounds the investigation of road condlitions of original pavement,indoor trial study,determination of trial lot plan as well as completion of trial lot etc. | yue_Hant | 51,996 |
[The diagnosis of mild closed craniocerebral injury in patients with chronic illnesses]. | Of 396 injured persons aged from 16 to 80 years, examined in an acute period of mild craniocerebral trauma (MCCT), 174 were healthy before the trauma moment (1st group), 112 had the arterial hypertension, chronic blood circulation of brain insufficiency (CBCBI) of I-II stages (2nd group), and 110-chronic gastrointestinal diseases (3d group). It is necessary to take into consideration the noted peculiarities of an acute period of MCCT clinical course in injured persons of the second and third groups while making diagnosis and administering the treatment. | This paper presents a comprehensive work to evaluate the long-term influence of concrete on the shear-lag effect in steel–concrete composite beams, for which rather few tests and numerical studies have been reported. The FE study demonstrates that the effective width is greatly influenced by the analytic models: linear creep (CnSnC model) linear creep with shrinkage (CSnC model) creep with shrinkage and cracking (CSC model). Some numerical results were not well clarified, as discussed in the following. | eng_Latn | 52,000 |
The Wooden Roofs of Leonardo and New Structural Research | The two types of spatial patterns reproduced in the Codex Altanticus fol. 899v can be deciphered in light of recent studies on reciprocal and tensegrity frames. For the construction of his wooden component roofs, Leonardo utilized two main modules: a grid of square modules and a grid of a tri/hexagonal module. Leonardo’s drawings offer an opportunity to attempt a synthesis between the two structural systems, demonstrating the affinity that exists between the reciprocal frames used by Leonardo and the rigid tensegrities developed by Fuller. The continual observation, study and construction of models have permitted the verification of this hypothesis. | This work was aimed at understanding mechanisms of importance for the design of weight-efficient armour against long-rod projectiles (LRP) and shaped charge (SC) warheads. The focus was on how to a ... | eng_Latn | 52,007 |
Cause and Prevention of Abnormal Cracks in Reinforced Concrete Bridges | In construction of reinforced concrete bridges,abnormal cracks are composed of the following cracks such as temperature cracks,contraction cracks,deformation cracks,rusty cracks,freezing and expanding cracks,material cracks,and construction cracks.Under different circumstances,some measures should be adopted in order to prevent cracks. | Abstract This study aims at the formulations of double-layer clad sheet compression forming based on the upper bound and the slab methods. Assuming the frictions between the upper and lower dies and the clad sheet are constant shear friction, which can be different. Making use of the upper bound method can get the shape of the outer surface, the effective strain distribution, and the compression force. However, the stress distributions just can be obtained by the slab method. In this study, effects of various compression conditions such as the clad thickness ratio, the shear yield stress ratio, the frictional factor ratio, the ratio of width thickness, the frictional factor on the compression characteristics are found by the two methods. It is noted that the comparisons between two methods with compression force are performed in order to realize the feasibility of the two analytical models. The effective knowledge can be offered to forging industries. | eng_Latn | 52,016 |
Headache (chronic tension-type) | Similar results for adverse effects have also been found in other studies for amitriptyline. | In the light of the situation that there are no provisions about fatigue load in the highway bridge design codes and specifications in China for the time being,this paper conducts a study of the determination method and principle of fatigue test load for the cable and girder anchorage structure of highway steel cable-stayed bridge,using the specifications abroad and fatigue cumulative damage theories,on the basis of the vehicle load statistic data collected in some cities and on some sections of the National Roads in the country,and also with reference to the traffic volume prediction in the feasibility study of Sutong Bridge and other relevant highway engineering technical standards. | pol_Latn | 52,024 |
ESWL for Large-Span Roof Based on Grouping Response Method | The method for equivalent static wind loads applicable to multi-responses is proposed in this paper. A modified load-response-correlation (LRC) method corresponding to a particular peak response is presented, and the similarity algorithm implemented to the group response is described. The main idea of the algorithm is that two responses can be put into one group if the value of one response is close to that of the other response, when the structure is subjected to equivalent static wind loads aiming at the other response. Based on the modified LRC, the grouping response method is put forward to construct equivalent static wind loading. This technique can simultaneously reproduce peak responses for some grouped responses. | The University of Minnesota engaged RRM Architects, with RRM's consultant, Earl ::: Walls Associates, to assist the Ad-Hoc Committee for Preplanning Analysis of ::: Academic Sciences. The results of that study comprise this report. | eng_Latn | 52,025 |
Durability of reinforced concretes under the combined action of carbonation and chloride ingress: Probabilistic analysis | This paper presents a comprehensive probabilistic model of reinforcement corrosion initiation under the combned action of carbonation and chloride ingress. The numerical results show that the probability of reinforcement corrosion initiation under the combined action is much higher than the case of only considering the action of single factor. | The paper introducess the implemented conditions which colling recycle of flexible base on Ying-DaLine.It over all xpounds the investigation of road condlitions of original pavement,indoor trial study,determination of trial lot plan as well as completion of trial lot etc. | eng_Latn | 52,030 |
EDGE RESTRAINT ROLLING OF DIFFICULT-TO-WORK MATERIALS. | Abstract : The feasibility of applying the technique of edge restraint rolling to the production of difficult-to-form aerospace materials was demonstrated Ti-6Al-4V was rolled above, near, and below the beta transus (1900, 1780, and 1650F). Edge cracking was completely eliminated when rolling with restraint and with a protective coating on the edges. (Author) | The paper introducess the implemented conditions which colling recycle of flexible base on Ying-DaLine.It over all xpounds the investigation of road condlitions of original pavement,indoor trial study,determination of trial lot plan as well as completion of trial lot etc. | yue_Hant | 52,032 |
Quantitative analysis of freeze-thaw durability of concrete | It describes the concrete freeze-thaw damage mechanism and process of freeze-thaw damage;according to the experimental results of concrete freeze-thaw cycle,analyzes concrete compressive strength、splitting tensile strength and flexural strength with the variation of the number of freezing and thawing,and established the concrete flexural strength of the exponential decay law of equation,so it can analyzes the freeze-thaw durability of concrete quantitatively;introduces the concept of freezing factor for further analysis of concrete durability and strength of the rela- tionship;meanwhile puts forward key measures to improve the performance of freeze-thaw resistance of concrete. | The paper introducess the implemented conditions which colling recycle of flexible base on Ying-DaLine.It over all xpounds the investigation of road condlitions of original pavement,indoor trial study,determination of trial lot plan as well as completion of trial lot etc. | eng_Latn | 52,033 |
Economic feasibility analyses of bridge aseismic strengthening | The negative influence of bridge damage on the transportation system under earthquake is discussed in this paper. The relative direct and indirect loss of the damaged system is researched. Based on the constitution of user cost, the unit user cost is assessed through building traffic demand and distribution model. Comparing the retrofit invest and benefit, the method of assessing economic feasibility of bridge aseismic strengthening is suggested. | Recently, Advancements in information technology increasingly compact, lightweight, easy to pursuing the needs of users as (Needs) to meet the complex application of various types of products have been released. In this study, Numerical analysis of stress distribution and to optimize the location of the inserted device use to consisting of PVC material on the card and load displacement. In addition, through the bending test to evaluate the reliability of the specimen was carried out the validation of numerical analysis. | eng_Latn | 52,034 |
Optimisation of a vehicle energy absorbing steel component with experimental validation | Abstract The paper deals with the optimisation of a tapered tubular steel component to be used as an energy-absorbing device in the front structure of a vehicle body. Aim of the optimisation problem is the minimisation of a load uniformity parameter evaluated as the ratio between the maximum and the average crushing loads. The optimisation problem takes into account two design variables describing a tapered geometrical configuration, the diameter of the component at one of its bounds and the tapering length. Two improved geometrical configurations have been found and have been experimentally tested to verify the numerical results with impact velocities up to 10 m/s. | In this paper,according to the theories of whole life appraisal,value engineering and environmental economics,and based on the Evaluation Standards for Green Building(GB/T 50378-2006) and Management Methods for Performance Evaluation on Commercial Residential Buildings,an economic performance evaluation system was established for green building.Furthermore,a comprehensive evaluation model was developed on the basis of fuzzy mathematics principal.The purpose of this study was to provide referential methods for evaluating the economic performance of green building. | eng_Latn | 52,042 |
Implementing inherently safer design in an existing plant | Although the best time for implementation of inherently safer design alternatives is during early process development and plant design, there are often opportunities to modify an existing plant to significantly enhance inherent safety. We will describe a modification to a bromine raw material handling facility, replacing an existing bulk storage tank with cylinders. Incident consequence analysis and quantitative risk analysis were used to understand the relative inherent safety characteristics of the design options. © 2005 American Institute of Chemical Engineers Process Saf Prog, 2006 | A study of the factors which affect the fold kinematic activities has been presented,through the design analysis,the sensitivity of acceleration vs.design was obtained.According to the sensitivity,the lengths of linkage and crank were determined as design variables.The optimization technique was applied to an ADAMS Model so as to minimize the value of acceleration.The result showed that the value of jerk was also improved while the value of acceleration was optimizing.It will improve the vibration properties and be the foundation of dynamics simulation later on. | eng_Latn | 52,057 |
I've been studying the Cox Proportional Hazards model, and this question is glossed over in most texts. Cox proposed fitting the coefficients of the Hazard function using a partial likelihood method, but why not just fit the coefficients of a parametric Survival function using the maximum likelihood method and a linear model? In any cases where you have censored data, you could just find the area under the curve. For example, if your estimate is 380 with standard deviation of 80, and a sample is censored >300, then there is an 84% probability for that sample in the likelihood calculation assuming normal error. | I've been studying the Cox Proportional Hazards model, and this question is glossed over in most texts. Cox proposed fitting the coefficients of the Hazard function using a partial likelihood method, but why not just fit the coefficients of a parametric Survival function using the maximum likelihood method and a linear model? In any cases where you have censored data, you could just find the area under the curve. For example, if your estimate is 380 with standard deviation of 80, and a sample is censored >300, then there is an 84% probability for that sample in the likelihood calculation assuming normal error. | I've been studying the Cox Proportional Hazards model, and this question is glossed over in most texts. Cox proposed fitting the coefficients of the Hazard function using a partial likelihood method, but why not just fit the coefficients of a parametric Survival function using the maximum likelihood method and a linear model? In any cases where you have censored data, you could just find the area under the curve. For example, if your estimate is 380 with standard deviation of 80, and a sample is censored >300, then there is an 84% probability for that sample in the likelihood calculation assuming normal error. | eng_Latn | 52,059 |
The hypothesis that superheavy particles as particles of cold dark matter decay in our Galaxy and are observed today as ultra-high energy cosmic rays is discussed. These particles were created from vacuum by the gravitational field of the inflaton field in the Grand Unification era. Supposing that they have some quantum number of the type of strangeness conserved in strong and gravitational interactions, it is claimed that, although they were created by gravity in pairs, they decay as long-living and short-living components. The decay of the short-living component at times close to the Grand Unification era, due to baryon charge nonconservation and CP -noninvariance, produces the observable baryon charge of the Universe, while the long-living component constitutes cold dark matter, and its decay produces the ultra-high energy cosmic rays events. | We consider the possibility of the quantum vacuum states in f(R,T) gravity. Particularly, we study the Bogoliubov transformations associated to different vacuum states for some f(R,T) models. The m... | 1and that these are possible sources of energies up to 100 PeV, above which extragalactic sources are believed to dominate. Even if only 10% of the supernova explosion energy (10 51 erg) goes into cosmic rays, they are energetically capable of delivering the requisite cosmic ray power of 10 42 erg/s into the interstellar medium. They may well be the only class of object within our galaxy with this capability. The acceleration mechanism of cosmic ray particles is most probably diffusive shock acceleration, which can produce the appropriate power and satisfy the requirement of a power law energy spectrum. | eng_Latn | 52,098 |
The F-GAMMA program: Multi-frequency study of Active Galactic Nuclei in the Fermi era. Program description and the first 2.5 years of monitoring | High-Sensitivity AGN Polarimetry at Sub-Millimeter Wavelengths | Corrected FIM effectiveness as an index independent of FIM score on admission | eng_Latn | 52,110 |
Application study of a correction method for a spacecraft thermal model with a Monte-Carlo hybrid algorithm | The correction of a thermal model for a thermally controlled satellite in ground test conditions is studied using a Monte Carlo hybrid algorithm. First, the global and local parameters are summarized according to sensitivity analyses on uncertain parameters, and then the model correction is treated as a parameter optimization problem to be solved with a hybrid algorithm. Finally, the correction of the thermal model is completed using a layered correction method. The sensitivity analysis showed that the effective emissivities across the multi-layer insulation (MLI) and the emissivities of the thermal control coating are global parameters, while the contact heat transfer coefficients are local parameters. After correction, the deviations between the calculated and test values were all within ±3°C. The final results prove that the method in this study is superior to traditional methods and satisfies the requirements for thermal model correction. | In determining the distances to stars within the Milky Way galaxy, one often uses photometric or spectroscopic parallax. In these methods, the type of each individual star is determined, and the absolute magnitude of that star type is compared with the measured apparent magnitude to determine individual distances. In this article, we define the term statistical photometric parallax, in which statistical knowledge of the absolute magnitudes of stellar populations is used to determine the underlying density distributions of those stars. This technique has been used to determine the density distribution of the Milky Way stellar halo and its component tidal streams, using very large samples of stars from the Sloan Digital Sky Survey. Most recently, the volunteer computing platform MilkyWay@home has been used to find the best fit model parameters for the density of these halo stars. | eng_Latn | 52,181 |
Ages and kinematics of clusters | The recent emphasis on stellar evolution, especially as seen in star clusters, has given us — mainly through Sandage's synthesis of the available material — a good outline of the evolutionary process. Although work of a survey nature obviously must be continued, if only to turn up clusters with an age not represented among those now known, I believe the time has come to concentrate a major effort on detailed studies of the brighter known clusters of various ages. Our knowledge of even the Hyades and Pleiades clusters is far from complete. A full account cannot be given here but I would like to mention some examples of the details in the colour-magnitude arrays that may eventually lead to important tests, or revisions, of current evolutionary models. | By using the AdS/CFT correspondence and Godel black hole background, we study the dynamics of heavy quark under a rotating plasma. In that case we follow Atmaja (2013) about Brownian motion in BTZ black hole. In this paper we receive some new results for the case of . In this case, we must redefine the angular velocity of string fluctuation. We obtain the time evolution of displacement square ::: and angular velocity and show that it behaves as a Brownian particle in non relativistic limit. In this plasma, it seems that relating the Brownian motion to physical observables is rather a difficult work. But our results match with Atmaja work in the limit . | eng_Latn | 52,185 |
Equation for traveling-wave tubes | In Chapter VI we have expressed the properties of a circuit in terms of its normal modes of propagation rather than its physical dimensions. In this chapter we shall use this representation in justifying the circuit equation of Chapter II and in adding to it a term to take into account the local fields produced by a-c space charge. Then, a combined circuit and ballistical equation will be obtained, which will be used in the following chapters in deducing various properties of traveling-wave tubes. | We search for the variable component of themagnetic field in γ Equ by studying four Nd III lines with the Main Stellar Spectrograph of the 6-m BTA telescope of the Special Astrophysical Observatory via accumulation and cyclic transfer of the electronic image of the Zeeman spectrum on the CCD. The single exposure time was set equal to 1/8 of the spectral variability period. We detected no variable component in the magnetic field of γ Equ with a period of 12.1 min in the November 5/6, 2003 observations. | eng_Latn | 52,204 |
Microstructure Evolution of Semi-Solid AZ91D Alloy During Isothermal Heat Treatment Process | The effect of isothermal heat treatment on the microstructure evolution of semi- solid AZ91 D magnesium alloy was investigated. The results show that the roundness of the primary α- Mg phase increases with the increasing temperature and time. The microstructure evolution of the semi-solid AZ91 D experiences three stages during isothermal heat treatment process, i.e. the structure separation,spheroidization and final coarsening. The liquid phase of semi- solid alloy has three types, namely, the molten pool, the"entrapped liquid"pool and the liner liquid film which separates two neighbor particles.The solid phase has two types, namely, the primary α-Mg particles and the α-Mg phase formed in the second solidification. | We present an asymptotic form of the Boussinesq equations in the limit of small P ´ eclet numbers i.e. when the time scale of motions is much larger than the time scale of ther- mal diffusion. We find that, in this limit, the effects of thermal diffusion and stable stratification combine in a single physical process. This process is an anisotropic dissipation (not effective for horizontal motions) which acts primarily on large scale mo- tions. The small-P´ eclet-number approximation presents also the great practical interest to avoid the numerical difficulty induced by the huge separation between the diffusive and dynamical time scales. The relevance of this approximation to study the flow dynamics within the stellar radiative zones is considered. | eng_Latn | 52,205 |
Monte Carlo simulations of geosynchrotron radio emission from CORSIKA-simulated air showers | Simulations of radio emission from extensive air showers we have published so far were performed with a Monte Carlo code using analytical parametrisations to describe the spatial, temporal, energy and angular particle distributions in the air shower. A new version of our simulation code, which replaces these parametrisations with precise, multi-dimensional histograms derived from per-shower CORSIKA simulations, is now available. The new code allows an independent selection between parametrisation and histogram for each of the relevant distributions, enabling us to study the changes arising from using a more realistic air shower model in detail. We describe the new simulation strategy, present some initial results and discuss the new possibilities. | Abstract According to the method described in reference [1], we have designed a series of corrector systems for Cassegrain telescopes automatically with an electronic computer. The calculations were carried out under the following two conditions: the primary and secondary mirrors have strictly conical surfaces, and the telescope is strictly free from third-order spherical aberration when the corrector systems are taken off. Results in this papercan be converted proportionally to real telescopes of any aperture, while the aberrations expressed in seconds of arc remain unchanged. | eng_Latn | 52,206 |
uvby - β photoelectric photometry of Cepheid stars | We present time-series uvby − β photometry of 41 classical Cepheid stars. A brief discussion of a comparison between the present data and previous photometric observations is included. | A method of solving the eikonal equation, in either flat or curved space–times, with arbitrary Cauchy data, is extended to the case of data given on a characteristic surface. We find a beautiful relationship between the Cauchy and characteristic data for the same solution, namely they are related by a Legendre transformation. From the resulting solutions, we study and describe the wave-front singularities that are associated with their level surfaces (the characteristic surfaces or “big wave fronts”). | eng_Latn | 52,208 |
Lawrence Berkeley National Lab is studying the universe through the brightness of these "super" explosions | Distant Exploding Stars Foretell Fate Of The Universe: It Will Expand ... Jan 13, 1998 ... By the time the light of the most distant supernova explosions so far discovered ... Although not all Type Ia supernova have the same brightness, their ... are supernovae and measure their redshifts using the Keck telescope, the world's largest. ... Lawrence Berkeley National Laboratory, ScienceDaily, 2003. | jeopardy/1052_Qs.txt at master jedoublen/jeopardy GitHub With the rising sun beating down on me I was doing this, as if I was a ... I went on a diet to try to do this, like chateaubriand sauce when it's boiled down | reduce. | eng_Latn | 52,254 |
Micro/nano patterning characteristics in hot embossing process | The hot embossing process has been known as one of major nano replication techniques. This is due to its simple process, low cost, high replication fidelity and relatively high throughput. As the initial step of quantitating the hot embossing process, simple parametric studies for the embossing time have been carried out using high‐resolution masters which patterned by DRIE process and laser machining. Under different embossing times, the viscous flow of thin PMMA films into micro cavities under the compression force has been investigated. Also, the viscous flow during the embossing process was simulated by the continuum based FDM analysis considering micro/nano effect, such as surface tension and contact angle. | We present an asymptotic form of the Boussinesq equations in the limit of small P ´ eclet numbers i.e. when the time scale of motions is much larger than the time scale of ther- mal diffusion. We find that, in this limit, the effects of thermal diffusion and stable stratification combine in a single physical process. This process is an anisotropic dissipation (not effective for horizontal motions) which acts primarily on large scale mo- tions. The small-P´ eclet-number approximation presents also the great practical interest to avoid the numerical difficulty induced by the huge separation between the diffusive and dynamical time scales. The relevance of this approximation to study the flow dynamics within the stellar radiative zones is considered. | eng_Latn | 52,269 |
Determination of point wave sources by boundary measurements | This paper is concerned with an inverse point wave sources problem in a bounded domain Ω⊂3 from boundary observations. Assuming that all point sources vanish after a certain time T1, we prove first an identifiability result provided that some condition is satisfied between the time T1, the observation interval (0,T) and the observation domain on the boundary. This condition is reduced to the inequality T>T1 + diam(Ω) when the observation domain is the whole boundary of Ω. In this case, we propose a method to identify completely the sources: their number, locations and intensities. | Bolometers operating at low temperature are discussed as detectors of heavy particles which have been recently considered as constituents of Cosmic Dark Matter. The study of the heat leak in a cascade refrigerator operating underground is suggested for the indirect detection of Weak Interacting Massive Particles. | eng_Latn | 52,272 |
Westerlund 1 as a Template for Massive Star Evolution | With a dynamical mass Mdyn ~ 1.3×105 M and a lower limit Mcl > 5 × 104 M from star counts, Westerlund 1 is the most massive young open cluster known in the Galaxy and thus the perfect laboratory to study massive star evolution. We have developed a comprehensive spectral classification scheme for supergiants based on features in the 6000–9000A range, which allows us to identify > 30 very luminous supergiants in Westerlund 1 and ~ 100 other less evolved massive stars, which join the large population of Wolf-Rayet stars already known. Though detailed studies of these stars are still pending, preliminary rough estimates suggest that the stars we see are evolving to the red part of the HR diagram at approximately constant luminosity. | Highly branched stilbene dendrimers underwent trans–cis isomerization in the excited singlet state within the lifetime of 10 ns. | eng_Latn | 52,300 |
MODIFICATION OF HIGH ENERGY γ-RAY SPECTRUM OF BLAZARS DUE TO INTERNAL AND INTERGALACTIC ABSORPTION | Blazars are effective emitters of γ-rays with spectra extending to GeV and TeV energies. In the case of distant TeV blazars, γ-rays undergo severe absorption due to interactions with diffuse intergalactic radiation fields resulting in significant deformations of the initial (source) spectra. Even for the lowest possible level of the Extragalactic Background Light (EBL), the absorption-corrected γ-ray spectra from some TeV blazars appear unusually hard, which cannot be explained within the standard particle acceleration models of blazars. The simplest and most natural solution of this problem seems to us the realization of internal absorption of γ-rays in narrow (e.g. Planckian type) radiation fields in the immediate vicinity of the γ-ray production region. | A simplified treatment is proposed to study quantitatively the lattice dynamics of CsK, CsRb, and RbK alloy systems. The volume effect on the lattice dynamics of the pure constituent is considered, and the phonon dispersion relations of the local and band modes are obtained forthe Rb0.71K0.29, Rb0.3K0.7, Cs0.7K0.3, Cs0.7Rb0.3, and Cs0.3Rb0.7 systems. Then, the x-dependence of the local and band mode frequencies is calculated for the Rb1−xKx, Cs1−xKx and Cs1−xRbx systems. | yue_Hant | 52,301 |
Quasar candidates near A1139, A1775, and 1633+33 | Lists of quasar candidates discovered with blue, blue green, and and green grens plates are presented, along with a discussion of the surface densities of quasars and a comparison with the 3C 345 field. The plates covered the fields A1139, A1775, and 1663+33. A total of 74 new candidate quasars were detected, with surface densities higher than usually observed with a slitless spectra technique. The 3C 345 field was filled with quasars brighter than 19 mag, although slit spectra are recommended for confirmation. | The main objective of this article is to study dynamic of the ::: three-dimensional Boussinesq equations with the periodic boundary ::: condition.We prove that when the Rayleigh number $R$ crosses the ::: first critical Rayleigh number $R_c$, the Rayleigh-Benard problem ::: bifurcates from the basic state to an global attractor $\Sigma$, which is homeomorphic to $S^3$. | eng_Latn | 52,311 |
Assessment of Chromium Release from Steel Manufacturing Waste | Industrial waste of different origins has been dumped for decades (1950–1980) in a landfill of 150,000 m2 area, a few km from the centre of Torino (NW Italy). A large portion of this landfill, estimated to be in the order of 1,100,000 m3 and extending over a surface of 55,000 m2, is composed of steel manufacturing waste. This study discusses an investigation of this waste mass in order to assess the total Cr concentration and solubility, identify the main Cr-bearing phases and estimate the release of Cr to rainwater leaching through the material and the consequent contamination of groundwater. Figure 1 provides a schematic representation of the landfill. | Iron emission is often a severe contaminant in optical-ultra- violet spectra of active galaxies. Its presence complicates emission line studies. A viable solution, already successfully applied at optical wave- lengths, is to use an empirical iron emission template. We have generated Fe ii and Fe iii templates for ultraviolet active galaxy spectra based on HST archival 1100-3100u spectra of IZw1. Their application allows fitting and subtraction of the iron emission in active galaxy spectra. This work has shown that in particular Ciii) �1909 can be heavily contam- inated by other line emission, including iron transitions. Details of the data processing, generation, and use of the templates, are given by Vester- gaard & Wilkes (2001). | eng_Latn | 52,314 |
Singular potentials in relativistic equations of motion | It is shown that in relativistic equations of motion for a particle moving in external potentials some additional forces of purely relativistic origin appear. These forces are repulsive for scalar and pseudoscalar potentials thus preventing the particle from coming too near to the singularity of the potential in spite of its apparently attractive character. An adiabatic approximation to the interaction potential for two nucleons interacting through the pseudoscalar field is obtained. An interesting feature of this potential is a strong repulsive term acting at short distances between nucleons. | We search for the variable component of themagnetic field in γ Equ by studying four Nd III lines with the Main Stellar Spectrograph of the 6-m BTA telescope of the Special Astrophysical Observatory via accumulation and cyclic transfer of the electronic image of the Zeeman spectrum on the CCD. The single exposure time was set equal to 1/8 of the spectral variability period. We detected no variable component in the magnetic field of γ Equ with a period of 12.1 min in the November 5/6, 2003 observations. | eng_Latn | 52,345 |
Investigation of cosmic-ray muon induced processes by the MIREDO facility | The MIREDO (Muon Induced Rare Event Dynamic Observatory) spectrometer system is primarily developed for the study of cosmic muon induced processes in different materials. Exploration of such interactions can be important for ultra-low background experiments. The system is based on the 100% relative efficiency ultra-low-background HPGe spectrometer. With the addition of two plastic scintillators and a fast-slow coincidence circuit, the coincidence events between the plastic detectors and the HPGe spectrometer have been investigated. First results derived for a CaO powder sample, placed in a Marinelli beaker, are presented and discussed. | Abstract A crystal field (CF) of axial symmetry is incorporated in the resonance model of Schotte and Schotte for magnetic multiplets of angular momentum j . The free energy for j = 5 2 and arbitrary level schemes is explicity evaluated and the competition between CF-splitting and Kondo effect in the susceptibility tensor is discussed. | eng_Latn | 52,362 |
Astronomy: Supernovae Offer a First Glimpse of the Universe's Fate | By studying Type Ia supernovae, exploding stars visible at distances so vast that they represent earlier epochs of cosmic history, astronomers are getting a look at the ultimate fate of the universe. By comparing the brightness of these beacons--an indicator of their distance--with the rate at which cosmic expansion is carrying them away, two groups of observers are now closing in on the rate at which cosmic expansion has changed over time. Early results suggest that high matter density is slowing the universe's expansion, and that the cosmos contains hundreds of times more mass than can be seen as stars and galaxies--a conclusion that may conflict with other clues suggesting a low-density universe ([see p. 36][1]). ::: ::: [1]: /lookup/doi/10.1126/science.276.5309.36 | AbstractThis article considers the understandings of space and place amongst a group of disaffected students within an institution that had been in a state of flux over a number of years. The artic... | eng_Latn | 52,368 |
Finding of new species of finless Sagittids (Sagittidae: Chaetognatha) in the northwestern Sea of Japan | Diagnosis of a new genus Abosagitta gen. n. and detailed descriptions and drawings of four new species, as well as keys for the identification of genera of Sagittidae, are given. The new species differ from species of other genera of Sagittidae by lacking lateral fins on the trunk. Instead of two pairs of lateral fins, these species have saclike gelatinous structures. These structures were previously found only in the species of Eukrohniidae (see [2, 4]). The presence of saclike gelatinous structures instead of fins is probably a plesiomorphic feature, which is retained only in some species. | Abstract We propose a mission called SADE, the Starspot And Dynamo Explorer, to study dynamo activity in nearby late-type stars. The onboard instruments will be a Ca-K telescope for magnetically dominated chromospheric emission, and an X-ray grazing incidence telescope to study coronal emission. We design the mission for a life-time of 15 years or longer to capture a full activity cycle for most solar-type stars. We aim to firmly establish the spectrum of the relation between chromospheric and corona' emission in late-type stars, and capture one or more stars going into or coming out of a Maunder type minimum. Operation costs will be kept to a minimum by automating mission operations to a maximum, and have the science operations be carried out by students at Montana State University. | eng_Latn | 52,374 |
Unlike previous long-term analyses, this study found some associations between mortality and ozone but found inconsistent results for PM indicators. | Inconsistent results were found for PM indicators in this study. | The study confirmed all of the findings presented in previous studies. | eng_Latn | 52,429 |
This will include a vigorous research program to further understand the fate and transport of pollutants in the atmosphere. | The ultimate fate and transport of pollutants will be further understood following a vigorous research program. | There are not pollutants to study in the atmosphere. | eng_Latn | 52,431 |
More progress urged on ozone hole | One of the scientists who found the Antarctic ozone hole urges more action on ozone-attacking chemicals. | Plans to protect Britain do not heed the risk of rising river levels caused by global warming, finds study. | eng_Latn | 52,459 |
what is the purpose of the atmosphere | Written by Marcia Malory. Category: Atmosphere. The atmosphere, a thin shell of gases surrounding the Earth, is a very effective protective shield that reflects and absorbs harmful radiation and objects like meteorites.The atmosphere protects the Earth from receiving too much radiation from the Sun.ritten by Marcia Malory. Category: Atmosphere. The atmosphere, a thin shell of gases surrounding the Earth, is a very effective protective shield that reflects and absorbs harmful radiation and objects like meteorites. | Overview. 1 Atmosphere - The atmosphere is the air around the Earth made up of different gasses (mostly nitrogen and oxygen). The atmosphere forms a protective layer around Earth, keeping the planet warm and protecting it from the Sun's radiation. The study of the atmosphere is called meteorology and includes the weather. | eng_Latn | 52,557 |
which molecules in the atmosphere absorb infrared radiation? | The only way to study the entire range of infrared (as well as gamma rays, xrays, UV) is to place telescopes in space well above the atmosphere. Only some (not all) of the IR radiation between 1 and 40 microns makes it to the Earth's surface. The rest is absorbed by our atmosphere primarily by water vapor. IR is also absorbed to a lesser degree by carbon dioxide and oxygen molecules. | Water vapor and certain gases in the atmosphere absorb infrared radiation, causing what is called the Greenhouse Effect. This infrared radiation comes from materials on the Earth's surface that have been heated by sunlight. | eng_Latn | 52,563 |
what generator uses del ozone chip | DEL Ozone Generators produce ozone gas which is introduced to the spa water through suction created by the spa. Tubing is used to connect the Ozone Generator to an injector or a vacuum port provided by the spa manufacturer. The injector or port are vacuum sources used to pull the ozone gas out of the Ozone Generator and into the water. At no time should water come in contact with the Ozone Generator. | There are a number of studies that have been performed to evaluate ozone output from air purifiers. In one study conducted by the U.S. Environmental Protection Agency (EPA), researchers ran an ozone generator in a test home at its maximum setting. | eng_Latn | 52,565 |
A study on numerical optimization and performance verification of multiphase pump for offshore plant | Performance Analysis of a Low-Pressure Three-Stage Axial Compressor | Backstepping control of the Stefan problem with flowing liquid | eng_Latn | 52,599 |
The term cluster or streamer is commonly applied to a collection of particles held together by hydrodynamic forces. Inside a circulating fluidized bed a single cluster has a significant effect on the gas that flows around it. Recent experiments have suggested that large scale gas fluctuations occur as the air flows around the cluster body. This paper examines the effect a single cluster has on the surrounding gas flow. Experimental work focuses on a small riser with the ability to release a single cluster. A specially designed probe measures the gas velocity as the cluster travels by. Numerical work simulates the effect of airflow around a porous body. The fluctuation levels observed are comparable to the experiments. Both results show that large scale velocity fluctuations occur in the gas in the vicinity of a cluster. This has a large impact on gas and particle modeling and mixing inside a circulating fluidized bed. | In this study, the mass transfer of three-dimensional nonreactive gas-solid fluidized bed was investigated computationally. The influence of the inlet gas velocity and temperature on mass transfer of air to wet particles was analyzed. The simulation results indicated that the mass transfer coefficients of air to spherical sand particles was decreased from 2.12 to 1.66 m/s with increment of temperature from 300 to 360 K. Sherwood numbers of gas to cluster increased with the increase of inlet air velocity. CFD model of the gas-particle heat transfer have been implemented, the result showed that the heat flux of gas to particles increased with the increase of Reynolds number. Distributions of water vapor concentration and velocity in this bed were numerically predicted and the computed Sherwood and Nusselt numbers were compared with the estimated values from empirical equations. | We prove that groups acting geometrically on delta-quasiconvex spaces contain no essential Baumslag-Solitar quotients as subgroups. This implies that they are translation discrete, meaning that the translation numbers of their nontorsion elements are bounded away from zero. | eng_Latn | 52,645 |
An experimental study of the pressure and heat-transfer distribution on a 70 deg sweep slab delta wing in hypersonic flow | Experimentally determined local flow properties and drag coefficients for a family of blunt bodies at Mach numbers from 2.49 to 4.63 | Stream hydraulics as a major determinant of benthic invertebrate zonation patterns | eng_Latn | 52,660 |
Regimes of two-phase flow in micro- and minichannels (review) | Hydrodynamic study of a monolith-type reactor for intensification of gas-liquid applications | Completely Stale Transmitter Channel State Information is Still Very Useful | eng_Latn | 52,679 |
The study of random vibration deals with random excitation processes and the response of vibratory systems to such excitations. The most frequent application is to vehicles (e.g., ships, trucks, airplanes, space vehicles) where the operational environment provides random dynamic excitation (e.g., stormy seas, rough roads, atmospheric turbulence, rocket engine noise). For an introduction to the field see [1, 2]. A survey of the present state of the art is provided by [3]. | The various techniques available for the analysis of nonlinear systems subjected to random excitations are briefly introduced and an overview of the progress which has been made in this area of research is presented. The discussion is mainly focused on the basis, scope and limitations of the solution techniques and not on specific applications. | The application of dynamic mesh method has been extensively applied for simulating piston wind-induced subway environments, e.g. air quality, which is not central processing unit-friendly in calcul... | eng_Latn | 52,717 |
The study is focused on developing and testing a 2-D microscale mathematical model and a numerical method for the analysis of turbulent flow and passive gaseous admixture transfer in street canyons. The model was tested by modeling laminar flow in the initial section of a 2-D channel and eddy flow in a channel with sudden expansion. After verification the model was used to study the flow structure in the street canyon depending on the ratio between channel width and building height. | A numerical microscale model of aerodynamics and the transport of pollution was developed. The model takes into account the nonhomogeneity of elements of the urban boundary layer. The numerical solution of the differential problem is based on the finite volume method. On the basis of experiments, a comparison of three different turbulent closure schemes and parameterizations of the urban vegetation was conducted. Turbulent air dynamics and the transport of pollution were modeled around an array of buildings. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 52,766 |
This study reports an approach and presents its open-source implementation for quantitative analysis of experimental flows using streak images and convolutional neural networks (CNN). The latter are applied to retrieve a length and an angle from streaks, which can be used to deduce kinetic energy and directionality (up to an $$180^{\circ }$$ ambiguity) of an imaged flow. We developed a quick method for generating essentially unlimited number of training and validation images, which enabled efficient training. Additionally, we show how to apply an ensemble of CNNs to derive a formal uncertainty on the estimated quantities. The approach is validated on the numerical simulation of a convective turbulent flow and applied to a longitudinal libration flow experiment. | Introduction.- Physical and technical background.- Mathematical background of statistical PIV evaluation.- PIV recording techniques.- Image evaluation methods for PIV.- Post-processing of PIV data.- Three-component PIV measurements on planar domains.- Examples of applications.- Bibliography.- Matrices for perspective projection.- Mathematical appendix.- List of symbols.- Index. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 52,784 |
The present light sheet system for 3D studies of the location and structure of transonic flows employs a CCD video camera and digital frame-store which are synchronized with the pulsed laser so that the resulting images can be immediately displayed via microcomputer. These video images are digitally enhanced in order to display 3D coordinate data. An illustrative demonstration of the system is for rotating transonic-jet flow. The visualized images show instantaneous transonic flow structures. | Holographic interferometry has been used in a large scale transonic wind tunnel to produce a 3D flow visualization. The experiments have been carried out on a model civil transport aircraft wing and turbine powered engine simulator combination. This study is significant industrially as the method forms a diagnostic for turbofan installations. The holograms show many relevant flow features including shock waves, flow interactions between the engine simulator flow and the freestream flow, secondary flows, and acoustic waves. Quantitative 3D position information has also been obtained for some of these features. A comparison to other flow diagnostic methods has been made in this paper.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only. | Berzelius failed to make use of Faraday's electrochemical laws in his laborious determination of equivalent weights. | eng_Latn | 52,790 |
A numerical analysis of vortex shedding within a confined channel flow | AbstractThe numerical analysis of two-dimensional laminar vortex shedding from a rectangular cylinder within a confined channel flow is presented. This study, carried out using a computational fluid dynamics (CFD) code based on the SIMPLEST algorithm, considers the influence of numerical diffusion on the prediction of the vortex shedding frequency. The computational analysis compares the commonly used first-order accurate UPWIND scheme with the well-known third-order scheme QUICK and its derivative SMART, used for the discretization of convective transport. For the temporal differencing, a fully implicit scheme has been adopted. Plots of Strouhal number against Reynolds number suggest that the implementation of a higher-order scheme is beneficial for the accurate capture of the vortex shedding transient in unsteady flows of this nature. | In this study, two apparently similar clays have been characterised using advanced rheometry and particle-sizing techniques; the data and the blend design consequences are discussed. The analytical information has been used in the design of casting slips which have been characterised by both traditional and advanced methods. Special emphasis has been given to the interpretation of the rheological data and the particle size distributions and how these can be combined in order to optimise the casting performance of the system. | eng_Latn | 52,815 |
Optimization and metabolic stabilization of a class of nonsteroidal glucocorticoid modulators. | Abstract The optimization of a series of nonsteroidal glucocorticoid modulators is reported. Potent selective GR ligands that have improved metabolic stability were discovered typified by the subnanomolar acid 12 (GR binding IC 50 = 0.6 nM). | A computational study on the supersonic flow around the lateral jet controlled missile has been performed. For this purpose a three dimensional Navier-Stokes computer code(AADL3D) has been developed and case studies have been performed by comparing the normal force coefficient and the moment coefficient of a missile body for several parameters such as angles of attack, circumferential jet positions, and spouting jet angles. Missile surface is divided into four regions with respect to the center of gravity, and the normal force and moment distribution at each region are compared. The results show different behavior of the normal force and moment variation according to each parameter. Furthermore, it is shown that the pitching moment can be minimized through proper combination of each parameter. | eng_Latn | 52,827 |
Motion of particles of magnetosensitive aerosol in a magnetic field | The results of an investigation of magnetosensitive aerosols prepared by atomizing magnetic fluids in a gas medium are presented. The possibility of controlling the motion of such media by using magnetic fields was shown. | A computational study on the supersonic flow around the lateral jet controlled missile has been performed. For this purpose a three dimensional Navier-Stokes computer code(AADL3D) has been developed and case studies have been performed by comparing the normal force coefficient and the moment coefficient of a missile body for several parameters such as angles of attack, circumferential jet positions, and spouting jet angles. Missile surface is divided into four regions with respect to the center of gravity, and the normal force and moment distribution at each region are compared. The results show different behavior of the normal force and moment variation according to each parameter. Furthermore, it is shown that the pitching moment can be minimized through proper combination of each parameter. | eng_Latn | 52,829 |
The Study of the Similarity Theory of the Debris Flow Model Experiment | The goal of this paper is to establish an experimental theory of the debris flow model as the foundation for future flow model construction through the characteristics of debris flow's basic movement: flow motion similarity and sediment motion similarity. The study yields 10 similarity rules in the debris flow model, which are useful in structuring the debris flow model as well as providing accurate data to the engineers in the prevention design process. This paper also studies the expanded debris flow and suggests two similarity rules, shear stress and viscosity index, which are different from Bingham's rules. These two rules serve as a reference in the graveled debris flow model experiment. | This paper discussed the time field information fusion technique based on the Dampster Shafter method. A new wear mode recognition method of marine diesel engine is put forward. This new method can decrease the uncertainty on the recognition. A wear mode recognition expert system is built and the reliability of recognition results is testified on the practice. | eng_Latn | 52,830 |
Experience of Nurbas Modeling Design Process | Nurbas curve modeling is one of a very important function of three-dimensional software, it provides another excellent way of modeling for three-dimensional object shape by its unique model features, which fully demonstrates functional advantages of its three-dimensional forming from the line to a surface, is a functional module which the other three-dimensional software must be integrated into. This paper based on the examples experience to study the Nurbas modeling characteristics and laws in 3DS MAX, to further enhance the ability of Nurbas modeling design, to enhance the understanding and grasp of the function. | Abstract Buoyancy-driven recirculating flows between two parallel plates, whose temperature varies sinusoidally, have been attentively investigated. In this study, we place our emphasis on joint effects rendered by both (a) the existence of two insulated side walls and (b) the phase of the bottom-surface sinusoidal temperature on the overall Nusselt number (Nu) of the system. Using the finite-element-based COMSOL and the finite-volume-based ANSYS Fluent packages, we have discovered that Nu is gradually affected by expansion and compression of vortices, as well as is abruptly affected by birth and death of vortices. Under the width-divided-by-height aspect ratio of ten, these gradual or abrupt variations for airflows remain conspicuous regardless of the wave number and the Rayleigh number. | eng_Latn | 52,850 |
Modeling with Fault Integration of the Cooling and the Lubricating Systems in Marine Diesel Engine: Experimental validation | Abstract In this paper, physical models for the cooling and the lubricating systems for marine diesel engine have been developed. The main purpose of this modeling is to integrate some possible faults that may be produced, and then to analyze their effects on the overall marine diesel engine during operation. Faults may appear in the model as the variation of some parameters. The importance of this study is to prepare an important data base for the fault diagnosis and prognosis strategies that may be applied on Diesel engines. Experimentations on Marine Diesel engine test bench have been used for the validation of the proposed model. | In this paper we study the dynamics of the Kepler-36 exoplanetary system. The two planets are engaged in the mean-motion resonance of 6:7. The dynamical stability of this system has been studied by numerical methods using a Lie-integrator and calculating the Lyapunov characteristic indicator (LCI) and maximum eccentricity (ME). We studied the stability of the system, the stability of another planet, and the stability of satellites belonging to the known planets. The possibility of trojans were also studied using the massless approximation. The tidal perturbations were neglected although they can become significant in some cases. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) | eng_Latn | 52,864 |
A Class of Nonlinear Degenerate Integrodifferential Control Systems | In this paper, we study the approximate controllability and noncontrollability for a class of nonlinear degenerate integrodifferential control systems. Based on the property of finite propagation for the disturbances, we prove noncontrollability. We also establish sufficient conditions for approximate controllability of the system in L2(\Omega) . Moreover, we prove the global existence and uniqueness of generalized solutions. | Simulating a radial-inflow turboexpander from its nozzle inlet to the impeller output as the single nozzle, and through theoretic analysis, this thesis concludes two general characteristic models for design and off-design steady-state of the turboexpanders. Based on experiment data, and generalized least squares method is used in imitation of the data, the coefficient solutions which are needed to describe the models have been obtained. Using the model to predict performance of the other two turboexpanders, the results show that the two general characteristic models in this thesis are more accurate and universal. Therefore, in design of turboexpanders, as two important models, they can give a base for optimizing design and off-design characteristic. | eng_Latn | 52,868 |
Experimental study of hydrodynamic and heat-transfer processes in the downward motion of a two-phase flow under annular and dispersed-annular conditions | Relationships are derived for determining the average thickness of a liquid film and the predominant frequency of the wave motion on its surface under conditions of two-phase flow; relationships are also derived for calculating the hydraulic resistance and the rate of heat transfer to the film under these conditions. | We present a novel numerical method based on finite differences to solve the problem of impurities' migration from a hollow core multilayer cylinder filled with a known liquid medium. We expose the numerical method and the developed application. The validation is performed by calculating the migration in a configuration which allows an analytic solution. Applications are foreseen in modeling impurities' migration from modern multilayer water pipes into drinking water. | eng_Latn | 52,886 |
UNSTEADY SIMULATION OF TURBULENT FLOW AND HEAT TRANSFER IN A CHANNEL WITH PERIODIC ARRAY OF CUBIC PIN‐FINS | Numerical study of turbulent heat and fluid flow in a straight square duct at higher Reynolds numbers | FULLY DEVELOPED TURBULENT PIPE FLOW | yue_Hant | 52,893 |
Allelopathic effects of exogenous phenolic acids composted by wheat straw on seed germination and seedling growth of rice | This experiment aimed to investigate allelopathic effects of phenolic acids composted by wheat straw at different concentrations on seed germination and seedling growth of rice by means of plate culture and sand culture.The results showed that the seed germination indexes in all phenolic acids treatments were promoted at lower acid concentrations and were inhibited at higher concentrations.Most of the phenolic acids played a promotive role at lower concentrations and an inhibitory role at higher concentrations in biomass accumulation,chlorophyll contents and root activity of rice as well.However on malondialdehyde content of rice,the phenolic acids presented opposite effect.The allelopathic effect of phenolic acid solution on rice was related to the kinds and concentrations of phenolic acid,and its threshold depended on the kinds. | Flexible wing surfaces can be observed in many natural flyers and their use in small engineered flying vehicles has translated too many beneficial properties. These benefits have manifested themselves in the aerodynamic forces as well as flight stability which are an effect of how the flow and the membranes interact both statically and dynamically. In this work, time dependent particle image velocimetry and digital image correlation are used to study the fluid structure interaction for flow over a membrane wing. The wings examined here are multi-cell silicon rubber membrane wings which have a scalloped free trailing edge with different levels of pretension. The pretension effects the natural frequencies of the membranes and is shown to affect the extension magnitude and membrane motion frequency which are both also affected by aerodynamic loading. Examinations of the membranes through time based and frequency domain analysis motions shows they are highly correlated with the flow. The velocity measurements... | eng_Latn | 52,900 |
Effect of Pulsations on the Wake Structure of a Circular Cylinder | The effect of flow perturbations (sinusoidal pulsations) on the wake structure of a circular cylinder in turbulent crossflow has been studied by means of LDA measurements along the wake axis. The results show the variation of the extent of the recirculation bubble and vortex formation regions and the longitudinal distance of the vortices in the von Karman street with pulsation frequency and amplitude within the lock-on range.Copyright © 2002 by ASME | The purpose of this note is to document some work done as part of the effort directed at designing and simulating a bunch-by-bunch feedback system to control longitudinal coupled bunch instabilities in the B-factory. In particular, I discuss the ring model used in the simulation program developed to study this feedback system. Basically the simulation is a simple tracking program in which the rf drive voltage, the wakefields due to all the bunches, the synchrotron radiation losses, and the kicks applied to the bunches by the bunch-by-bunch feedback are all modelled as voltages applied at a single, discrete point in the ring. The computation of the bunch-by-bunch feedback voltages may of course be done by any desired algorithms. An example and discussion of the general behavior without bunch-by-bunch feedback is given at the end of this report. | eng_Latn | 52,903 |
STATISTICAL TREATMENT OF HOT CHANNEL FACTORS FOR COMPACT REACTORS | The theoretical development, statistical treatment, and application of hot channel factors in compact SNAP reactors as represented by the SNAP 8 experimental core loading are presented. The channel and rod power effects of variation in the concentrations of uranium, hydrogen, and poison in the fuel rods are given. The statistical distributions of all variables are examined. A random selection of rods and channels is compared to the actual SNAP 8 configuration, with no difference noted. Confidence limits are set on hot rod and hot channel factors. Various other factors and aspects of the problem are discussed. The results of the study showed that the hot channel factors may be reduced to less than +2% over the nominal power, as opposed to a hot channel factor of about +10% as previously determined by empirical methods. (auth) | In this paper, by using the coefficient mapping from plant to GPC closed-loop system in the IMC structure, the stability conditions for closed-loop system with respect to selection of tuning parameters are derived. Furthermore, some simple conditions described by step response coefficients for tuning parameters which guarantee the stability of the closed-loop system are also obtained. | kor_Hang | 52,910 |
Numerical Simulation of 3-D Flow Field in the Sand Funnel | The computation region of the sand funnel is treated by special means so that some reasonable boundary conditions can be adopted.Volume of Fluid(VOF) method is introduced to trace free-surface.The RNG model is used for turbulence modeling,all of which is combined.The 3-D water-air two-phase flow field in the sand funnel is simulated,and free-surface position,static pressure and velocity distribution are obtained.The comparison between velocity distribution and experimental results obtained from numerical calculation was conducted.The computed result has some instructive significance to study the characteristic of flow field in the sand funnel. | In this paper, the results of a series of elastoplastic large deflection analyses on a specific cylindrical shell part of the ship hull girders under inplane compression is reported. Nonlinear finite element method is applied in the calculations. It is revealed that the assumption of elastic-perfectly plastic behaviour for this part of the ship hulls is not realistic and may result in very optimistic predictions of the ship hull overall strength. | eng_Latn | 52,923 |
Observation and Numerical Simulation of Heterogenous Underlying Surface Boundary Layer (II): Numerical Simulation of Inverse Humidity Phenomenon | Bascd on the whole physical of inverse humidity given in literature, a new scheme of land-surface process parameterization is designed. The new scheme has successfully simulated appearing the inverse humidity phenomenon in desert near oasis. The simulated result is coincident with the observed ones, so that the new scheme of land-surface process parameterization is feasible. These conclusions are beneficial to study heterogeneous land-surface process. | The first step of the /spl Hscr//sub /spl infin// loop shaping design procedure is to specify desired closed loop performance by shaping the singular values of the nominal plant with a pre- and/or a post-compensator. Designers usually choose diagonal weighting functions but it is not always possible to obtain the desired loop shape with diagonal weights. This paper develops a systematic procedure for designing nondiagonal pre- and post-compensators. Such nondiagonal weighting functions enable the designer to shape each singular value of the nominal plant separately. To illustrate the procedure an /spl Hscr//sub /spl infin// loop shaping controller is designed for a plant whose singular values can not be shaped accurately using diagonal weights. | eng_Latn | 52,927 |
Finite Element Analysis of Seepage through an Earthen Dam by using Geo-Slope (SEEP/W) software | In this research work, finite element approach is employed to solve the governing differential equations pertaining to seepage through body of dam its foundation. For this purpose, the foremost focal point is discretization of domain into finite elements by placement of imaginary nodal points and discretization of governing equations into a system of equations; an equation for each nodal point or element and solving it for the unknown variables. | This paper addresses an initial study of a modelfree PID tuning based on simultaneous perturbation stochastic approximation (SPSA) for liquid slosh control. The SPSA method is used to optimize the PID parameters such that the liquid slosh is minimized. In order to validate our model-free design, a liquid slosh model is considered to represent the lateral slosh motion. The simulation results demonstrate that the proposed model-free method has a good potential in reducing the liquid slosh without explicitly modeling the liquid slosh behavior. | eng_Latn | 52,928 |
Penalty finite-element analysis of coupled fluid flow and heat transfer for in-line bundle of cylinders in cross flow | Abstract The two-dimensional steady state Navier-Stokes equations and the energy equation governing laminar incompressible flow are solved using a penalty finite-element model for the case of flow across an in-line bundle of cylinders. Two cases of in-line cylinder bundles, one five rows deep and the other an infinite bundle, are considered with pitch-diameter ratios of 1.25, 1.5 and 1.8 Reynolds numbers studied range from 100 to 600 and Prandtl number is taken as 0.7. Velocity field vectors, stream lines, vorticity, pressure and temperature contours, local and average Nusselt numbers, pressure and shear stress distribution around the cylinder walls and drag coefficients are presented. The results obtained agree well with available experimental and numerical data. | A real case of a steel lattice shell suffering a fire was studied. Based on the theory of field modeling, fire dynamic simulator (FDS) was used to identify the temperature field. The damage mechanism of the structure was determined by FEM analysis. After damage assessment, the shell was repaired with the pipe-encasement method. Finally, field test was employed to check the capacity of the structure after repair. The numerical study results indicate that the damage assessment agrees well with field inspection, verifying the accuracy of fire numerical simulation and FEM analysis. The field test results prove that the pipe-encasement method is secure and reasonable, and the repaired shell is safe. | eng_Latn | 52,929 |
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