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https://astronomy.stackexchange.com/questions/39784/missing-line-in-solar-spectrum/39786#39786
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# Missing line in solar spectrum
Referring to this answer to What's the rationale behind the false colours in solar observation photographs? which includes the table from Wikipedia's Fraunhofer lines:
In the Table of wavelengths there is an e designated Hg line of 546.07 nm which DOES NOT appear in the picture of the Fraunhofer spectrum, any explanation? Also there are about a dozen lines in the spectrum which are not tabulated and not identified at all.
• i.stack.imgur.com/oEcmv.png They are really small but just to the right of the big "G" I think I see "f" then "e" but interestingly, "e" is listed at both 438.355 and 546.073 hmm...
– uhoh
Nov 12 '20 at 3:51
• +1 for asking what turns out to be a very interesting question!
– uhoh
Nov 12 '20 at 22:56
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http://math.stackexchange.com/questions/106940/computing-gradient-and-hessian-of-a-vector-function
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# Computing Gradient and Hessian of a vector function
I'm wondering how to compute gradient and hessian for this function $$f(\textbf{x}) = ||\textbf{x}||_2^p$$, where $\textbf{x}$ is a vector and $p$ is a constant and $p>1$.
This is a homework question. As I'm unfamiliar with vector calculus which is the prerequisite of my class, I'm having a difficult time finding the solution. I'll appreciate it if you can give me reference to materials of vector calculus that helps finding the solution of this problem.
The original homework question is to perform Newton's method to minimize $f(x)$. So I'm thinking of computing gradient and Hessian. Any hints on the original question will be appreciated.
Thanks
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$f(x_1,...,x_)=(x_1^2+...+x_n^2)^{\frac p 2}$ – azarel Feb 8 '12 at 4:59
As $$f(\mathbf{x}):=||\mathbf{x}||_{2}^{p}=\left(\sum_{i=1}^{n}x_{i}^{2}\right)^{p/2}$$ and $$\nabla f(\mathbf{x}) := \left(\frac{\partial f}{\partial x_{1}},\frac{\partial f}{\partial x_{2}}, \ldots, \frac{\partial f }{\partial x_{n} } \right)$$ and noting that $$\frac{\partial f}{\partial x_{j}} = \frac{p}{2}\left(\sum_{i=1}^{n} x_{i}^{2} \right)^{p/2-1}\cdot 2x_{j} =px_{j}||\mathbf{x}||_{2}^{p-2}$$ then $$\nabla f(\mathbf{x})=p||\mathbf{x}||_{2}^{p-2}\left(x_{1},x_{2},\ldots, x_{n}\right)$$ As for the Hessian, $$\nabla^{2}f := \begin{pmatrix} \frac{\partial^{2} f}{\partial x_{1}^{2}} & \frac{\partial^{2} f}{\partial x_{1} \partial_{x_{2}}} & \cdots &\frac{\partial^{2} f}{\partial x_{1}\partial_{x_{n}}} \\ \frac{\partial^{2} f}{\partial x_{2} \partial x_{1}} & \frac{\partial^{2} f}{\partial x_{2}^{2}} & \cdots & \frac{\partial^{2} f}{\partial x_{2}\partial_{x_{n}}} \\ \vdots & \vdots & \ddots & \vdots \\ \frac{\partial^{2} f}{\partial x_{n} \partial_{x_{1}}} & \frac{\partial^{2} f}{\partial x_{n} \partial_{x_{2}}} & \cdots & \frac{\partial^{2} f}{\partial x_{n}^{2}} \end{pmatrix}$$ so we consider two cases: The diagonal elements and off-diagonal elements. These entries are computed easily from standard rules of calculus; I'm too worn out to compute them explicitly.
A good book on vector calculus is Div, Grad, Curl, And All That: An Informal Text on Vector Calculus by H.M. Schey. Newton's Method in the multivariate case is a pretty straightforward generalization of the single-variable case, noting that $$f(\mathbf{x}+\mathbf{h})\approx f(\mathbf{x})+\left<\nabla f(\mathbf{x}),\mathbf{h} \right> + \frac{1}{2}\left<\mathbf{h},\nabla^{2}f(\mathbf{x})\mathbf{h}\right>$$ where $\left<\cdot, \cdot\right>$ denotes the ordinary dot product on $\mathbb{R}^{n}$.
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Thanks Nick. I see where this is going. But I have another question: is it easy to get inverse of the Hessian? – SeeBees Feb 8 '12 at 5:44
Absolutely not. There are schemes for getting around having to invert the Hessian which I have forgot, I believe that can be found in Kendall Atkinson's book <em>Theoretical Numerical Analysis</em>. – Nick Thompson Feb 8 '12 at 5:47
But if I want to compute $H^{-1} * g$, where $H$ is the Hessian and $g$ is the gradient, would there be easy way? – SeeBees Feb 8 '12 at 5:54
Hit both sides with $H$ then use Cholesky decomposition to solve the resulting system. – Nick Thompson Feb 8 '12 at 7:34
@SeeBees: Take a look at Pearlmutter and Schraudolph's work on the R technique that approximates exactly that in linear time. – Neil G Oct 31 '14 at 12:11
The second derivatives are
$$\frac{\partial^2 f}{\partial x_i^2}=\frac{\partial}{\partial x_i}\left(px_i\left(\mathbf x^2\right)^{p/2-1}\right)=p\left(\left(\mathbf x^2\right)^{p/2-1}+(p-2)x_i^2\left(\mathbf x^2\right)^{p/2-2}\right)$$
and
$$\frac{\partial^2 f}{\partial x_i\partial x_j}=\frac{\partial}{\partial x_i}\left(px_j\left(\mathbf x^2\right)^{p/2-1}\right)=p(p-2)x_ix_j\left(\mathbf x^2\right)^{p/2-2}$$
for $i\ne j$, so the Hessian matrix $H$ is given by
$$H=p\left(\mathbf x^2\right)^{p/2-2}\left((\mathbf x^\top\mathbf x) I+(p-2)\mathbf x\mathbf x^\top\right)\;,$$
where $I$ is the identity matrix. Symmetry suggests that its inverse should then also be a linear combination of $I$ and $\mathbf x\mathbf x^\top$, and you can find it by using that as an ansatz and determining the coefficients of the linear combination from the condition that the product is the identity matrix. (You'll need to use $(\mathbf x\mathbf x^\top)(\mathbf x\mathbf x^\top)=\mathbf x(\mathbf x^\top\mathbf x)\mathbf x^\top=(\mathbf x^\top\mathbf x)\mathbf x\mathbf x^\top$ in the process.)
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Thanks. Is there any good tutorial on matrix calculus? I'm unfamiliar with basic rules. – SeeBees Feb 9 '12 at 20:14
@SeeBees: This isn't what I'd call matrix calculus (on which there is, by the way, a Wikipedia article). It's just calculus that leads to a matrix, and then inverting that matrix involves only ordinary matrix operations, not calculus. In case you mean that you're unfamiliar with the basic rules of matrix operations, this Wikipedia section might be a good place to start. I can't recommend any books because I learned linear algebra from a German book way back when :-) – joriki Feb 9 '12 at 20:24
I was able to derive the gradient by the doing the following:
$f(\mathbf x) = (\mathbf x ^\top \mathbf x) ^{p/2}$
$f'(\mathbf x) = p/2 (\mathbf x^\top \mathbf x) ^{(p-2)/2} 2\mathbf x = p (\mathbf x^\top \mathbf x) ^{(p-2)/2} \mathbf x$
I'm wondering if this is what's called matrix calculus.
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https://math.stackexchange.com/questions/3188106/directional-derivative-in-the-direction-in-which-z-is-growing
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# Directional Derivative in the direction in which $z$ is growing
Find the directional derivative of $$f(x, y, z) = xy + 2xz - y^2 + z^2$$, at the point $$P = (1, -2, 1)$$, passing through the curve $$x = t, y = t -3, z = t^2$$, in the direction in which $$z$$ is growing.
The work I've done:
$$\nabla f = (y + 2z, x - 2y, 2x + 2z) \Rightarrow \nabla f \rvert _P = (0, 5, 4)$$
Now I'm not sure of what I'm doing. Substituting the values of $$P$$ in the parametric equation of the curve, you get $$(1, 1, 1)$$. What I mean is,
$$1 = t, -2 = t - 3, 1 = t^2$$
When you solve for $$t$$ in each equation you get $$(1, 1, 1)$$. So my guess is that
$$\vec{v} = (1, 1, 1)$$
Therefore the directional derivative is
$$\nabla f \rvert _P \cdot \frac{\vec{v}}{|\vec{v}|} = \frac{4 + 5}{\sqrt{3}} = 3\sqrt{3}$$
Is that correct?
No, you get $$t= 1$$, not three different values. Each value of $$t$$ gives a point on the curve. $$t= 1$$ gives $$x= 1, y= 1- 3= -2, z= 1^2$$ or the point $$(1, -2, 1)$$ that you were given to begin with. The "directional derivative", also called a "tangent vector" is the function you got, $$(0, 5, 4)$$.
• thanks for clearing it up.. what about the part "in the direction in which $z$ is growing?" – Victor S. Apr 15 at 0:01
• The tangent vector could also be given as $(0,-5,-4)$ but that would not be in the correct direction it would be $z$ decreasing (pointing downwards in the 3d plane). – Peter Foreman Apr 15 at 0:31
• Well the official answer is $13\sqrt{6}/6$. This is why I think I must be wrong. – Victor S. Apr 15 at 0:40
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https://www.mezzacotta.net/100proofs/archives/tag/electromagnetism
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## 11. Auroral ovals
Aurorae are visible light phenomena observed in the night sky, mostly at high latitudes corresponding to Arctic and Antarctic regions. An aurora can appear as an indistinct glow from a distance or as distinct shifting curtain-like formations of light, in various colours, when seen from nearby.
An aurora, observed near Eielson Air Force Base, near Fairbanks, Alaska. (Public domain image by Senior Airman Joshua Strang, United States Air Force.)
Aurorae are caused by the impact on Earth’s atmosphere of charged particles streaming from the sun, known as the solar wind.
Schematic representation of the solar wind streaming from the sun and interacting with the Earth’s magnetic field. The dashed lines indicate paths of solar particles towards Earth. The solid blue lines show Earth’s magnetic field. (Public domain image by NASA.)
The Earth’s magnetic field captures the particles and deflects them (according to the well-known laws of electromagnetism) so that they spiral downwards around magnetic field lines. The result is that the particles hit the atmosphere near the Earth’s magnetic poles.
Diagram of the solar wind interacting with Earth’s magnetic field (field lines in red). The magnetic field deflects the incoming particles around the Earth, except for a fraction of the particles that enter the magnetic polar funnels and spiral down towards Earth’s magnetic poles. (Public domain image by NASA. modified.)
The incoming high energy particles ionise nitrogen atoms in the upper atmosphere, as well as exciting oxygen atoms and nitrogen molecules into high energy states. The recombination of nitrogen and the relaxation of the high energy states results in the emission of photons. The light is produced between about 90 km and 150 km above the surface of the Earth, as shown by triangulating the positions of aurorae from multiple observing locations.
Observations of aurorae have established that they occur in nearly-circular elliptical rings of width equivalent to a few degrees of latitude (i.e. a few hundred kilometres), usually between 10° and 20° from the Earth’s magnetic poles. These rings, in the northern and southern hemispheres, are called the auroral ovals.
Northern auroral oval observed on 22 January 2004. Figure reproduced from [1].
The auroral ovals are not precisely centred on the magnetic poles, but rather are pushed a few degrees towards the Earth’s night side. This is caused by the diurnal deflection of the Earth’s magnetic field by pressure from the charged particles of the solar wind.
Northern auroral oval observed in 1983 by Dynamics Explorer 1 satellite. The large bright patch at left is the daylight side of Earth. (Public domain image by NASA.)
The auroral ovals also expand when solar activity increases, particularly during solar storms, when increased particle emission from the sun and the resulting stronger solar wind compresses the Earth’s magnetic field, forcing field lines to move away from the poles.
But despite these variations, the auroral ovals in the northern and southern hemispheres move and change sizes more or less in unison, and are always of similar size.
Southern auroral oval observed in 2005 by IMAGE satellite, overlaid on a Blue Marble image of Earth. (Public domain image by NASA.)
You can see the current locations and sizes of both the northern and southern auroral ovals as forecast based on the solar wind and interplanetary magnetic field conditions as measured by the Deep Space Climate Observatory satellite at https://www.spaceweatherlive.com/en/auroral-activity/auroral-oval.
Current northern and southern auroral ovals as forecast by spaceweatherlive.com on 21 April, 2019. The auroral ovals are the same size and shape.
Earth is not the only planet to display aurorae. Jupiter has a strong magnetic field, which acts to funnel the solar wind towards its polar regions in the same way as Earth’s field does on Earth. Jupiter we can establish by simple observation from ground-based telescopes is close to spherical in shape and not a flat disc. Auroral ovals are observed on Jupiter around both the northern and southern magnetic poles, exactly analogously to on Earth: of close to the same size and shape.
Auroral ovals on Jupiter observed in the northern and southern polar regions by the Hubble Space Telescope, using the Wide Field Planetary Camera (1996) and the Space Telescope Imaging Spectrograph (1997-2001). Figure reproduced from [2].
Similar auroral ovals are also seen on Saturn, in both the northern and southern hemispheres [3][4]. And just for the record, Saturn is also easily shown to be spherical in shape, and not a flat disc.
Now, we have established that auroral ovals appear on three different planets, with the southern and northern ovals of close to the same sizes and shapes on each individual planet. Everything is consistent and readily understandable – as long as you assume that the Earth is spherical like Jupiter and Saturn.
If the Earth is flat, however, then the distributions of aurorae in the north and south map to very different shapes and sizes – with no ready explanation for either the shapes or their differences. In particular, large parts of the southern auroral oval end up being extremely far from the southern magnetic pole, in defiance of the electromagnetic mechanism that causes aurorae in the first place.
Auroral ovals in their observed locations, mapped onto a flat disc Earth. The ovals are vastly different sizes.
So the positions of aurorae on a flat Earth cannot be readily explained by known laws of physics, and they also do not resemble the locations and sizes of auroral ovals as observed on other planets. All of these problems go away and become self-consistent if the Earth is a globe.
References:
[1] Safargaleev, V., Sergienko, T., Nilsson, H., Kozlovsky, A., Massetti, S., Osipenko1, S., Kotikov, A. “Combined optical, EISCAT and magnetic observations of the omega bands/Ps6 pulsations and an auroral torch in the late morning hours: a case study”. Annales Geophysicae, 23, p. 1821-1838, 2005. https://doi.org/10.5194/angeo-23-1821-2005
[2] Grodent, D.,Clarke, J. T., Kim, J., Waite Jr., J. H., Cowley, S. W. H. “Jupiter’s main auroral oval observed with HST‐STIS”. Journal of Geophysical Research, 108, p. 1389-1404, 2003. https://doi.org/10.1029/2003JA009921
[3] Cowley, S. W. H., Bunce, E. J., Prangé, R. “Saturn’s polar ionospheric flows and their relation to the main auroral oval”. Annales Geophysicae, 22, p.1379-1394, 2004. https://doi.org/10.5194/angeo-22-1379-2004
[4] Nichols, J. D., Clarke, J. T., Cowley, S. W. H., Duval, J., Farmer, A. J., Gérard, J.‐C., Grodent, D., Wannawichian, S. “Oscillation of Saturn’s southern auroral oval”. Journal of Geophysical Research, 113, A11205, 2008. https://doi.org/10.1029/2008JA013444
## 8. Earth’s magnetic field
Magnetic fields have both a strength and a direction at each point in space. The strength is a measure of how strong a force a magnet feels when in the field, and the direction is the direction of the force on a magnetic north pole. North poles of magnets on Earth tend to be pulled towards the Earth’s North Magnetic Pole (which is in fact a magnetic south pole, but called “the North Magnetic Pole” because it is in the northern hemisphere), while south poles are pulled towards the South Magnetic Pole (similarly, actually a magnetic north pole, called “the South Magnetic Pole” because it’s in the south). Humans have used this property of magnets for thousands of years to navigate, with magnetic compasses.
The simplest magnetic field is what’s known as a dipole, because it has two poles: a north pole and a south pole. You can think of this as the magnetic field of a simple bar magnet. The magnetic field lines are loops, with the field direction pointing out of the north pole and into the south pole, and the loops closing inside of the magnet.
Illustration of magnetic field lines around a magnetic dipole. The north and south poles of the magnet are marked.
It’s straightforward to measure both the strength and the direction of the Earth’s magnetic field at any point on the surface, using a device known as a magnetometer. So what does it look like? Here are some contour maps showing the Earth’s magnetic field strength and the inclination – the angle the field lines make to the ground.
Earth’s magnetic field strength. The minimum field strength occurs over South America; the maximum field strengths occur just off Antarctica, south of Australia, and in the broad patch covering both central Russia and northern Canada. (Public domain image by the US National Ocean and Atmospheric Administration.)
Earth’s magnetic field inclination. The field direction is parallel to the ground at points along the green line, points into the ground in the red region, and points out of the ground in the blue region. The field emerges vertically at the white mark off the coast of Antarctica, south of Australia – this is the Earth’s South Magnetic Pole. The field points straight down at the North Magnetic Pole, north of Canada – not shown in this Mercator projection map, which omits areas with latitude greater than 70° north or south. (Public domain image by the US National Ocean and Atmospheric Administration.)
Now, how can we explain these observations with either a spherical Earth or flat Earth model? Let’s start with the spherical model.
You may notice a few things about the maps above. The Earth’s magnetic field is not symmetrical at the surface. The lowest intensity point over South America is not mirrored anywhere in the northern hemisphere. And the South Magnetic Pole is at a latitude about 64°S, while the North Magnetic Pole is at latitude 82°N. As it happens, this observed magnetic field is to a first approximation the field of a magnetic dipole – just not a dipole that is centred at the centre of the Earth. The dipole is tilted with respect to Earth’s rotation, and is offset a bit to one side – towards south-east Asia and away from South America. This explains the minimum intensity in South America, and the asymmetry of the magnetic poles.
The Earth’s magnetic field is approximated by a dipole, offset from the centre of the Earth. The rotational axis is the light blue line, with geographic north and south poles marked. The red dots are the equivalent magnetic poles. The North Magnetic Pole is much closer to the geographic north pole than the South Magnetic Pole is to the geographic south pole. (As stated in the text, the “North Magnetic Pole” of the Earth is actually a magnetic south pole, and vice versa.)
Models of the interior of the Earth suggest that there are circulating electrical currents in the molten core, which is composed mostly of iron. These currents are caused by thermal convection, and twisted into helices by the Coriolis force produced by the Earth’s rotation, both well understood physical processes. Circulating electrical currents are exactly what causes magnetic fields. The simplest version of this so-called dynamo theory model is one in which there is a single giant loop of current, generating a simple magnetic dipole. And in fact this dipole fits the Earth’s magnetic field to an average deviation of 16% [1].
This is not a perfect fit, but it’s not too bad. The adjustments needed to better fit Earth’s measured field are relatively small, and can also be understood as the effects of circulating currents in the Earth’s core, causing additional components of the field with smaller magnitudes. (The Earth’s magnetic field also changes over time, but we’ll discuss that another day.)
If the Earth is flat, however, there is no such relatively simple way to understand the strength and direction of Earth’s magnetic field using standard electromagnetic theory. Even the gross overall structure—which is readily explained by a magnetic dipole for the spherical Earth—has no such simple explanation. The shape of the field on a flat Earth would require either multiple electrical dynamos or large deposits of magnetic materials under the Earth’s crust, and they would have to be fortuitously arranged in such a way that they closely mimic a dipole if we assumed the Earth to be a sphere. For any random arrangement of magnetic field-inducing structures on a flat Earth to happen to mimic the field of a spherical planet so closely is highly unlikely. Potentially it could happen, but the Earth actually being a sphere is a much more likely explanation.
That the simpler model is more likely to be true than the one requiring many ad-hoc assumptions is a case of Occam’s razor. In science, particularly, a simpler theory is more easily testable than one with a large number of ad-hoc assumptions. Occam’s razor will come up a lot, and I should probably write a sidebar article about it.
References:
[1] Nevalainen, J.; Usoskin, I.G.; Mishev, A. “Eccentric dipole approximation of the geomagnetic field: Application to cosmic ray computations”. Advances in Space Research, 52, p. 22-29, 2013. https://doi.org/10.1016/j.asr.2013.02.020
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http://lambda-the-ultimate.org/node/1960
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## Matching Objects With Patterns
Matching Objects With Patterns. Burak Emir, Martin Odersky, and John Williams.
Data in object-oriented programming is organized in a hierarchy of classes. The problem of object-oriented pattern matching is how to explore this hierarchy from the outside. This usually involves classifying objects by their run-time type, accessing their members, or determining some other characteristic of a group of objects. In this paper we compare six different pattern matching techniques: object-oriented decomposition, visitors, type-tests/typecasts, typecase, case classes, and extractors. The techniques are compared on nine criteria related to conciseness, maintainability and performance. The paper introduces case classes and extractors as two new pattern-matching methods and shows that their combination works well for all of the established criteria.
## Comment viewing options
### Another approach
I have to mention here another interesting (but I'm probably biased here) approach, which is proposed by the Tom language.
This language allows to integrate algebraic pattern matching in languages such as Java or C. It permits pattern matching over arbitrary object structures, provided the user gave a so called anchor, that tells how to view those concrete objects as algebraic terms. It was first proposed in A Pattern Matching Compiler for Multiple Target Languages
then this notion of anchor was formally defined in Formal Validation of Pattern Matching Code and Formal Islands.
as pattern matching is independent from the concrete representation of objects, it can be used for example to manipulate algebraically XML using the standard DOM library in Java. The language currently offers not only classical algebraic pattern matching, but also associative pattern matching, aimed at manipulating lists, and provides a strategy language used to traverse tree structures, for in depth exploration of object structures.
All this make it a quite powerful language for manipulation, alalyse and transformation of complex object structures, in a high level manner.
### more than algebraic patterns
Dear Antoine, we cited the paper you mention (...multiple target languages), and any effort to promote pattern matching to Java people is great!
However, note that we don't just integrate algebraic pattern matching, but work towards an object-oriented concept of pattern matching -- one that encompasses algebraic patterns, but plays well with extensibility and data abstraction.
AFAICT Tom achieves integration in one direction because it is translated to a host language. It would be helpful (and a strong argument for TOM) if you could post a solution to one of the problems solved in the paper.
### .
I wanted to say that i wasn't criticizing the paper, I enjoyed reading it, and it gives a clear view of those different techniques and the issues.
I enjoyed the extractor part, as it seems close to the mapping Tom uses. For example, the "Twice" operator example in Section 4 can be written in Tom:
%include {int.tom}
%op int Twice(n:int) {
is_fsym(t) { t%2==0 }
get_slot(n, t) { t/2 }
make(t) { t*2 }
}
public final static void main(String[] args) {
int x = Twice(21);
%match(x) {
Twice(y) -> { System.out.println(x+" is two times "+y); }
_ -> { System.out.println(x+" is a number"); }
}
}
The "_" part will always be executed, as the %match construct in Tom behaves like the switch instruction of Java: after a sucessfull match, the control flow passes to the next pattern unless there is an explicit return or break.
### Interesting paper. I enjoyed
Interesting paper. I enjoyed reading it.
Stylistic suggestion: Less use of "on the one hand/on the other hand" constructions...
### Thanks for the compliment!
Thanks for the compliment!
Regarding the style, on the one hand, we should have avoided repeating that construction, on the other hand it only appears three times! : ) Seriously, it is not easy to make a comparison between different techniques without stressing the trade-offs involved.
Regarding the upcoming discussion in this forum, I wonder if functional programmers will recognize GADTs as such when they appear in a programming language that happens *not* to be Haskell or ML?
### .
I almost couldn't recognized GADTs in this paper and they said it was about GADTs and I'm an OO programmer by day ;)
Now for something completely different, as there is a connection between OO and coalgebra wouldn't make sense for have GCaDT as well?
### Nice ideas
I too would like to thank the authors for an interesting paper.
I have long wondered why a simple-yet-powerful concept like pattern matching only ever seems to be provided by functional programming languages. I appreciate that it has a strong fit with the typical type systems used in the field, but when we have concepts like enumerations and inheritance in typical industrial OO languages, pattern matching seems a logical next step.
Personally, I have often wished for something like a "matches" operator, which I'll denote ~ in this post (though this symbol is used in several major languages already). This would effectively be a syntactic shorthand for a single match, so that for example the expression c ~ Card Heart val would evaluate to true if c is any heart card, and would bind val to whatever the value of c is. (As an aside, you could also give the expression a Maybe ResultType type, so a successful match could yield a meaningful value, and you could also bind a variable of static type Card during the match if c where a more general type.)
Given the typical syntax in C-style languages, the deep example in the paper would become something like this:
simplified_e = (e ~ Mul x (Num 1)) ? x : e;
which isn't far from the code presented. In the absence of deep matching, and with the typical shortcut evaluation semantics for logical-and in these languages, we could also write something like:
simplified_e = (e ~ Mul x y && y ~ Num 1) ? x : e;
Here the scope of the variables bound in the matches can safely extend to the second term of the logical-and and into the true result for the ?: operator, because we know all necessary matches have succeeded at these points.
Going back to the paper, I was particularly impressed with the concept of injection and extraction. I had envisaged overloading the "matches" operator and conversion constructors on a class type to provide similar functionality, but providing a separate conversion interface independent of the definition of the class type has clear advantages over the approach I'd contemplated.
For what it's worth, I think the single most significant result in the paper is that in the benchmarks, there was not a huge performance penalty for using this approach rather than the traditional OO-style decomposition. In other words, we could benefit from the expressive power of pattern matching even in low-level, high-performance languages. Given that most RTTI-based features in mainstream OO languages come with some sort of performance penalty attached, this result is reassuring.
### It's the JIT
Dear Chris, thanks for the compliment. While it is reassuring, it also means that performance is much less predictable from the source, because one needs more information on what the JIT does (and ideally, how it does it). As remarked in the paper, we expected a performance penalty, and it came as quite a surprise that performance was that good (especially for cast). The Sun guys have embraced instanceof without telling anybody :)
### OO approach
Nice paper, especially the extractor idea. Like all Scala related papers very interesting work!
I think that the real OO approach is missing, though: OO is supposed to let the objects do the work, i.e. not to decompose them. Therefore the OO approach would look more like the following:
trait Expr {
def isUnit : boolean = false
def simplified : Expr = this
}
class Num(val value : int) extends Expr {
override def isUnit = value == 1
}
class Mul(val left : Expr, val right : Expr) extends Expr {
override def simplified = if (right.isUnit) left.simplified else super
}
// simplification
Mul(x, Num(1)).simplified // result: x.simplified
Compared to the OO-decomposition this is much more concise, because only one test is needed. Furthermore the test is related to the domain and does not expose the structure.
Compared to all examples in the paper, the method "simplified" simplifies the whole expression without having to iterate over it "by hand".
### fixed functionality
Dear Thorsten, thanks. The real OO approach you describe is left out for a reason. People often argued like this, e.g. in response to Martin's blog entry on pattern matching. If we want to make pattern matching popular among the masses, we will have to be clearer on where to draw the line -- but I think most experienced OO designer (experienced as in: burnt by mistakes in real life projects) would see the problems with the approach.
Can you agree with this motto: I would never use this approach at all, except when I am the author of the class and 100% sure that this functionality will not change. Adding a new method means changing all the classes.
The paper however looks for solutions to decomposing "from the outside", the scenario being that one does not have the luxury of owning the classes, or that you have to design classes such that people can add meaningful operations on them without needing access to their source code.
### spoilt by Smalltalk
I'm probably spoilt by using Smalltalk in real life projects, which allows extending existing classes with new functionality :-)
Transferring this idea to Scala, it would be nice to be able to write something like the following. Of course, the extensions should only be visible from within the Simplification module (and its users).
module Expr {
trait Expr { }
class Num(val value : int) extend Expr { }
class Mul(val left : Expr, val right : Expr) extend Expr { }
}
module Simplification {
import Expr
extend trait Expr {
def isUnit : boolean = false
def simplified : Expr = this
}
extend class Num {
override def isUnit = value == 1
}
extend class Mul {
override def simplified = if (right.isUnit) left.simplified else super
}
}
In mainstream languages where this is not possible, I agree that there it will often be neccessary to be able to decompose from the outside.
To clarify: I'm not against pattern matching. In fact I like it. But I like the OO approach, too :-)
### virtual classes
In Scala its fairly easy to get virtual classes using a pattern, your example in Scala:
trait Base {
type Expr <: ExprImpl;
trait ExprImpl { def self : Expr; ...}
type Num <: Expr with NumImpl;
trait NumImpl extends ExprImpl { def self : Mult; val value : Int; }
def Num(value : Int) : Num;
type Mult <: Expr with MultImpl;
trait MultImpl extends ExprImpl { def self : Mult; val left : Expr; val right : Expr; }
def Mult(val left : Expr, val right : Expr) : Mult;
}
trait Simplification extends Base {
type Expr <: ExprImpl;
trait ExprImpl extends super.ExprImpl {
def self : Expr;
def isUnit = false;
def simplified : Expr = this;
}
type Num <: Expr with NumImpl;
trait NumImpl extends super.NumImpl with ExprImpl {
def self : Num;
override def isUnit = value == 1;
}
type Mult <: Expr with MultImpl;
trait MultImpl extends super.MultImpl with ExprImpl {
def self : Mult;
override def simplified = if (right.isUnit) left.simplified else super.simplified;
}
}
class Compose extends Somplified {
trait Expr extends ExprImpl { def self : Expr; }
case class Num(value : Int) extends NumImpl with Expr { def self = this; }
case class Mult(left : Expr, right : Expr) extends MultImpl with Expr { def self = this; }
}
You can compose multiple extensions together using mixin-inheritance, its very flexible: I've implemented a large software system using this pattern and I'm very satisfied with the results. Of course, we need better syntactic sugar for this; i.e., Scala should support virtual classes in its syntax to support virtual class extension directly.
### self-type annotations?
Thanks for the nice example.
Any reason not to use explicitly typed self references, instead of defining self methods in each trait & class?
I mean:
trait Base {
type Expr <: ExprImpl;
trait ExprImpl { self : Expr => /*...*/}
type Num <: Expr with NumImpl;
trait NumImpl extends ExprImpl { self : Num => val value : Int; }
val Num : Int => Num;
type Mult <: Expr with MultImpl;
trait MultImpl extends ExprImpl { self : Mult => val left : Expr; val right : Expr; }
val Mult : (Expr, Expr) => Mult;
}
trait Simplification extends Base {
type Expr <: ExprImpl;
trait ExprImpl extends super.ExprImpl { self : Expr =>
def isUnit = false;
def simplified : Expr = self;
}
type Num <: Expr with NumImpl;
trait NumImpl extends super.NumImpl with ExprImpl { self : Num =>
override def isUnit = value == 1;
}
type Mult <: Expr with MultImpl;
trait MultImpl extends super.MultImpl with ExprImpl { self : Mult =>
override def simplified = if (right.isUnit) left.simplified else super.simplified;
}
}
class Compose extends Simplification {
trait Expr extends ExprImpl
case class Num(value : Int) extends NumImpl with Expr
case class Mult(left : Expr, right : Expr) extends MultImpl with Expr
}
Is there any reason NOT to do this? Thanks.
### No, not at all. When I did
No, not at all. When I did this (5 years ago), something pushed me away from explicit self types, though I have no recollection of what that was. Today, Scala has changed a lot; explicit self types are probably more robust now.
### Exhaustiveness/redundancy checks
I, too, enjoyed reading the paper. I have one major gripe, though: one central aspect of pattern matching seems to be completely missing from the discussion, and that is the ability to statically verify exhaustiveness and redundancy of patterns. Personally, I find this even more important than the terseness provided by nested patterns, especially when it comes to extending and maintaining existing programs. After all, that is the core motivation of static typing.
I fear that most of the presented approaches do not fare very well in this respect, since they all seem to require default cases. It may be interesting to discuss if and how each can be modified to get out better checking.
### I noticed this too, and
I noticed this too, and assumed that the goal of extensibility
conflicted with the goal of exhaustiveness checking.
I'd like to see some approach to this (maybe "final" case classes or
somesuch) myself. So far all of my Scala code is "toy" sized, but
my experience with OCaml (and C vs Ada) has convinced me that the exhaustiveness checking is a good thing. Much more important to me
than having XML built into the language...
### incompleteness check implemented
hello, I feel the urge to render this discussion thread a bit more timeless by announcing that the incompleteness check was added to the Scala implementation, roughly one month or two after the post above. however, so far it is not combined with extractors. some workable convention is needed to tell the compiler "this set of extractors is mutually exclusive and complete for this type", so that incompleteness checking can be enabled for extractors aswell.
It's true that extensibility clashes with incompleteness checking, that's why the curent implementation does it only if the sealed keyword is present and the match is on case classes. Mikael Pettersson's 1992 CC paper is very helpul in implementing incompleteness checking.
|
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|
https://motls.blogspot.com/2007/09/steve-mcintyre-and-praha-libus.html?m=0?m=1
|
Sunday, September 02, 2007 ... //
Steve McIntyre and Praha-Libuš
Steve McIntyre has started to look at the climate records outside the Americas. I was pleased that he picked Prague:
Slicing some Czech salami
He offers some high-tech reverse engineering to argue that a missing number in the database was used to shift one of the datasets by 0.1 Celsius degrees. His theory seems to be consistent with details of the data and seems to imply an unjustifiable bias.
Figure 1: The Meteorological Street, connecting the old and new part of Praha-Libuš, a neighborhood on the southern border of Prague (see Google Maps). On this street, you can also find the Meteorological Elementary School (WWW). ;-) A home page of the weather station is here. See also current temperature (Praha-Libuš is in the middle) or a whole PDF document about the weather station - it's full of pictures of the station (pages 3,4,8,14, and others) as well as graphs (e.g. page 26).
Figure 2: Prague ham.
Please don't confuse Libuš and Luboš. Libuš is rumored to have been a place with extraordinarily geese already during the reign of the female Prophet Libuše after whom the neighborhood is apparently called. ;-)
As one of the links above shows, Praha-Libuš and Praha-Ruzyně (close to the international airport, Western border of the capital) are becoming the main two weather science places in Prague. The traditional place to measure the weather was Praha-Klementinum in the middle of Prague. See e.g. the average annual temperatures over there since 1775.
|
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|
https://labs.tib.eu/arxiv/?author=Ying%20Yu
|
• ### Monolithic quantum-dot distributed feedback laser array on silicon(1801.01052)
April 28, 2018 physics.optics, physics.app-ph
Electrically-pumped lasers directly grown on silicon are key devices interfacing silicon microelectronics and photonics. We report here, for the first time, an electrically-pumped, room-temperature, continuous-wave (CW) and single-mode distributed feedback (DFB) laser array fabricated in InAs/GaAs quantum-dot (QD) gain material epitaxially grown on silicon. CW threshold currents as low as 12 mA and single-mode side mode suppression ratios (SMSRs) as high as 50 dB have been achieved from individual devices in the array. The laser array, compatible with state-of-the-art coarse wavelength division multiplexing (CWDM) systems, has a well-aligned channel spacing of 20 0.2 nm and exhibits a record wavelength coverage range of 100 nm, the full span of the O-band. These results indicate that, for the first time, the performance of lasers epitaxially grown on silicon is elevated to a point approaching real-world CWDM applications, demonstrating the great potential of this technology.
• ### Causes and Corrections for Bimodal Multipath Scanning with Structured Light(1706.02715)
June 8, 2017 cs.CV
Structured light illumination is an active 3-D scanning technique based on projecting/capturing a set of striped patterns and measuring the warping of the patterns as they reflect off a target object's surface. As designed, each pixel in the camera sees exactly one pixel from the projector; however, there are exceptions to this when the scanned surface has a complicated geometry with step edges and other discontinuities in depth or where the target surface has specularities that reflect light away from the camera. These situations are generally referred to multipath where a given camera pixel receives light from multiple positions from the projector. In the case of bimodal multipath, the camera pixel receives light from exactly two positions from the projector which occurs when light bounce back from a reflective surface or along a step edge where the edge slices through a pixel so that the pixel sees both a foreground and background surface. In this paper, we present a general mathematical model and address the bimodal multipath issue in a phase measuring profilometry scanner to measure the constructive and destructive interference between the two light paths, and by taking advantage of this interesting cue, separate the paths and make two separated depth measurements. We also validate our algorithm with both simulation and a number of challenging real cases.
• ### Optical positioning of single quantum dots in micropillar with >65% extraction efficiency for on-demand quantum light sources(1612.08180)
Feb. 11, 2017 quant-ph, physics.optics
We report optical positioning single quantum dots (QDs) in planar cavity with an average position uncertainty $<$20 nm using an optimized two-color photoluminescence imaging technique. We create single-photon sources based on these QDs in determined micropillar cavities. The brightness of the QD fluorescence is greatly enhanced on resonance with the fundamental mode of the cavity, leading to an high extraction efficiency of 68%$\pm$6% into a lens with numerical aperture of 0.65, and simultaneously exhibiting low multi-photon probability ($g^{2}(0)$=0.144$\pm$0.012) at this collection efficiency.
• ### Experimental detection of polarization-frequency quantum correlations in a photonic quantum channel by local operations(1311.5034)
Nov. 26, 2015 quant-ph
The measurement of correlations between different degrees of freedom is an important, but in general extremely difficult task in many applications of quantum mechanics. Here, we report an all-optical experimental detection and quantification of quantum correlations between the polarization and the frequency degrees of freedom of single photons by means of local operations acting only on the polarization degree of freedom. These operations only require experimental control over an easily accessible two-dimensional subsystem, despite handling strongly mixed quantum states comprised of a continuum of orthogonal frequency states. Our experiment thus represents a photonic realization of a scheme for the local detection of quantum correlations in a truly infinite-dimensional continuous-variable system, which excludes an efficient finite-dimensional truncation.
• ### Storage of multiple single-photon pulses emitted from a quantum dot in a solid-state quantum memory(1510.05358)
Oct. 19, 2015 quant-ph, physics.optics
Quantum repeaters are critical components for distributing entanglement over long distances in presence of unavoidable optical losses during transmission. Stimulated by Duan-Lukin-Cirac-Zoller protocol, many improved quantum-repeater protocols based on quantum memories have been proposed, which commonly focus on the entanglement-distribution rate. Among these protocols, the elimination of multi-photons (multi-photon-pairs) and the use of multimode quantum memory are demonstrated to have the ability to greatly improve the entanglement-distribution rate. Here, we demonstrate the storage of deterministic single photons emitted from a quantum dot in a polarization-maintaining solid-state quantum memory; in addition, multi-temporal-mode memory with $1$, $20$ and $100$ narrow single-photon pulses is also demonstrated. Multi-photons are eliminated, and only one photon at most is contained in each pulse. Moreover, the solid-state properties of both sub-systems make this configuration more stable and easier to be scalable. Our work will be helpful in the construction of efficient quantum repeaters based on all-solid-state devices
• ### Zinc-blende and wurtzite GaAs quantum dots in nanowires studied using hydrostatic pressure(1507.06418)
July 23, 2015 cond-mat.mes-hall
We report both zinc-blende (ZB) and wurtzite (WZ) crystal phase self-assembled GaAs quantum dots (QDs) embedding in a single GaAs/AlGaAs core-shell nanowires (NWs). Optical transitions and single-photon characteristics of both kinds of QDs have been investigated by measuring photoluminescence (PL) and time-resolved PL spectra upon application of hydrostatic pressure. We find that the ZB QDs are of direct band gap transition with short recombination lifetime (~1 ns) and higher pressure coefficient (75-100 meV/GPa). On the contrary, the WZ QDs undergo a direct-to-pseudodirect bandgap transition as a result of quantum confinement effect, with remarkably longer exciton lifetime (4.5-74.5 ns) and smaller pressure coefficient (28-53 meV/GPa). These fundamentally physical properties are further examined by performing state-of-the-art atomistic pseudopotential calculations.
• ### Assessing Technical Performance in Differential Gene Expression Experiments with External Spike-in RNA Control Ratio Mixtures(1406.4893)
June 18, 2014 q-bio.GN
There is a critical need for standard approaches to assess, report, and compare the technical performance of genome-scale differential gene expression experiments. We assess technical performance with a proposed "standard" dashboard of metrics derived from analysis of external spike-in RNA control ratio mixtures. These control ratio mixtures with defined abundance ratios enable assessment of diagnostic performance of differentially expressed transcript lists, limit of detection of ratio (LODR) estimates, and expression ratio variability and measurement bias. The performance metrics suite is applicable to analysis of a typical experiment, and here we also apply these metrics to evaluate technical performance among laboratories. An interlaboratory study using identical samples shared amongst 12 laboratories with three different measurement processes demonstrated generally consistent diagnostic power across 11 laboratories. Ratio measurement variability and bias were also comparable amongst laboratories for the same measurement process. Different biases were observed for measurement processes using different mRNA enrichment protocols.
• ### Tuning exciton and biexciton transition energies and fine structure splitting through hydrostatic pressure in single InGaAs quantum dots(1308.1494)
Aug. 7, 2013 cond-mat.mes-hall
We demonstrate that the exciton and biexciton emission energies as well as exciton fine structure splitting (FSS) in single (In,Ga)As/GaAs quantum dots (QDs) can be efficiently tuned using hydrostatic pressure in situ in an optical cryostat at up to 4.4 GPa. The maximum exciton emission energy shift was up to 380 meV, and the FSS was up to 180 $\mu$eV. We successfully produced a biexciton antibinding-binding transition in QDs, which is the key experimental condition that generates color- and polarization-indistinguishable photon pairs from the cascade of biexciton emissions and that generates entangled photons via a time-reordering scheme. We perform atomistic pseudopotential calculations on realistic (In,Ga)As/GaAs QDs to understand the physical mechanism underlying the hydrostatic pressure-induced effects.
• ### Experimental test of the tradeoff relation in weak measurement(1306.1027)
June 5, 2013 quant-ph
An upper bound between the information gain and state reversibility of weak measurement was first developed by Y. K. Cheong and S. W. Lee [Phys. Rev. Lett. 109, 150402 (2012)]. Their results are valid for arbitrary d-level quantum systems. In light of the commonly used qubit system in quantum information, a sharp tradeoff relation can be obtained. In this letter, this tradeoff relation is experimentally verified with polarization encoded single photons from a quantum dot. Furthermore, a complete traversal of weak measurement operators is realized, and the mapping to the least upper bound of this tradeoff relation is obtained. Our results complement the theoretical work and provide a universal ruler for the characterization of weak measurements.
|
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|
https://matlab-monkey.com/celestialMechanics/CRTBP/LagrangePoints/LagrangePoints.html
|
# CRTBP Pseudo-Potential and Lagrange Points
#### 1. Pseudo-Potential
When the motion of the test particle is confined to the plane containing the massive bodies, the acceleration in the rotating reference frame may be written in the form:
where U is defined as the pseudo-potential. We monkeys define the potential the way physicists do, i.e. in an isolated gravitational well the potential is negative. The celestial dynamics literature often defines U as becoming more positive the deeper one drops into a well. So, if you are a dynamicist, the sign of the potential will look wrong to you.
The first term on the right-hand-side generates the centrifugal force. The second and third terms are the gravitational potentials for masses m1 and m2.
The following figure shows the potential represented as a surface plot for a mass ratio of m2/m1 = 0.1:
• crtbpPotentialSurface.m - Plots the surface of the pseudo-potential for the circular, restricted three-body. Requires crtbpPotential.m to run.
Dependent files:
• crtbpPotential.m - returns the pseudo-potential for the circular, restricted three-body
#### 2. Jacobi Integral and Zero-Velocity Curves
While neither energy nor angular momentum are conserved in the rotating reference frame of the CRTBP, there is a quantity that is a constant of the motion. This quantity is called the Jacobi integral:
The form of the Jacobi integral is similar to the total energy: it has two terms, one a pseudo-potential and the other a quadratic velocity term like the kinetic energy. The Jacobi integral for a particle will remain constant as it orbits the system. This property may be exploited to place bounds on the particle's motion. For a given Jacobi integral, one can calculate the curve in space where the velocity would go to zero. Such curves are called zero-velocity curves are are equivalent to turning points for potential wells in inertial frames of reference.
The following figure shows zero velocity curves for different Jacobi integrals. The zero-velocity curves bound the shaded 'forbidden' regions where a particle with the specified Jacobi integral can not venture. For example, if a particle with CJ = 4 is initially in orbit around the green planet, it will be stuck there forever (unless it is given a velocity boost by some means). However, the zero-velocity curve for CJ = 3.92 encompasses both m1 and m2. Therefore a particle with this value of CJ can transition back and forth between orbits around each object.
This plot also show the positions of the five Lagrange points (see next section).
• crtbpZeroVel.m - Plots zero-velocity curves for difference values of the Jacobi integral. Also marks the positions of the Lagrange points with "+" symbols. Requires crtbpPotential.m and lagrangePoints.m to run.
Dependent files:
• crtbpPotential.m - returns the pseudo-potential for the circular, restricted three-body
• lagrangePoints.m - returns a matrix containing the (x,y,z) coordinates of the five Lagrange points for given values of m1 and m2. This routine assumes that G = 1 and the distance between the primary objects in 1.
#### 3. Lagrange Points
Lagrange points (a.k.a. libration points) are equilibrium points in the rotating frame. They correspond to places where the pseudo-potential is locally flat. Lagrange showed that there are five such points for any mass ratio m2/m1. Two Lagrange points, L4 and L5, form an equilateral triangle with the two primary masses, one above the masses and the other below. The remaining three Lagrange points L1, L2, L3 lie along the line containing m1 and m2. The positions of the colinear points require solving the roots of a set of fifth order polynomials. The MATLAB program lagrangePoints.m determines the solution numerically for given masses m1 and m2.
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https://arxiv.org/abs/0806.3145
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quant-ph
# Title:Operator quantum error correction for continuous dynamics
Abstract: We study the conditions under which a subsystem code is correctable in the presence of noise that results from continuous dynamics. We consider the case of Markovian dynamics as well as the general case of Hamiltonian dynamics of the system and the environment, and derive necessary and sufficient conditions on the Lindbladian and system-environment Hamiltonian, respectively. For the case when the encoded information is correctable during an entire time interval, the conditions we obtain can be thought of as generalizations of the previously derived conditions for decoherence-free subsystems to the case where the subsystem is time dependent. As a special case, we consider conditions for unitary correctability. In the case of Hamiltonian evolution, the conditions for unitary correctability concern only the effect of the Hamiltonian on the system, whereas the conditions for general correctability concern the entire system-environment Hamiltonian. We also derive conditions on the Hamiltonian which depend on the initial state of the environment, as well as conditions for correctability at only a particular moment of time. We discuss possible implications of our results for approximate quantum error correction.
Comments: 11 pages, no figures, essentially the published version, includes a new section on correctability at only a particular moment of time Subjects: Quantum Physics (quant-ph) Journal reference: Phys. Rev. A 78, 022333 (2008) DOI: 10.1103/PhysRevA.78.022333 Cite as: arXiv:0806.3145 [quant-ph] (or arXiv:0806.3145v2 [quant-ph] for this version)
## Submission history
From: Ognyan Oreshkov [view email]
[v1] Thu, 19 Jun 2008 08:31:48 UTC (17 KB)
[v2] Sat, 23 Aug 2008 12:33:56 UTC (19 KB)
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https://brilliant.org/problems/keeps-sliding/
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# Keeps sliding!
Algebra Level 3
A man wants to climb a pole 50m tall pole. At first, he first climbs 1m but slides down 1m back to the ground. Then, he climbs 2m, but slides down 1m. Then, he climbs 3m, but slides down by 1m. Then, he climbs 4m, but slides down by 1m, and so on.
If the man spends 10 seconds for each meter he climbs up and 5 seconds for each meter he slides down, then how many seconds will it take him to reach the top of the pole?
×
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https://brilliant.org/practice/prime-factorization-and-divisors-level-1-2/?subtopic=integers&chapter=prime-factorization-and-divisors
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Number Theory
Prime Factorization and Divisors: Level 2 Challenges
$$\color{red}{A}$$ and $$\color{blue}{B}$$ are whole numbers that do not contain 0 as a digit when expressed in base 10
If $$\color{red}{A} \times \color{blue}{B} = 10000,$$ then what is $$\color{red}{A}+\color{blue}{B}?$$
A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:
There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?
Note: The first locker that the $$n$$-th student changes is the $$n$$-th locker.
How many trailing zeros are there in the number $$3^4 \times 4^5 \times 5^6$$?
$\sqrt { { 17 }^{ 2 }+{ 17 }^{ 2 }+{ 17 }^{ 2 }+...+{ 17 }^{ 2 }+{ 17 }^{ 2 }+{ 17 }^{ 2 } }\\ ={ 17 }^{ 2 }+{ 17 }^{ 2 }+{ 17 }^{ 2 }$
How many times should $${17}^{2}$$ appear under the square root sign for the equation above to be true?
How many 3 digit numbers have exactly 3 factors?
×
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https://www.physicsforums.com/threads/why-does-the-temperature-decreases-with-increase-in-altitude.45274/
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# Why does the temperature decreases with increase in altitude
• Start date
• #1
36
0
1)what is entropy ?
2)why does the temperature decreases with increase in altitude
Related Other Physics Topics News on Phys.org
• #2
Clausius2
Gold Member
1,435
5
1) Once my physics teacher told me the entropy is like God, some people believes in God but other do not believe in it. The entropy has a variety of definitions (depending on probabilistic or macroscopic-thermodynamic meaning). The definition I'm going to give you is just that given by the 2nd principle:
Entropy (of a closed system): a thermodynamic variable which suffers an increasing in an adiabatic process.
You can imagine a lot of definitions, all of that based on the thermodynamics equations.
2) Usually, the density decreases with temperature: $$\rho=\frac{P}{R_g T}$$. So that, lighter air masses are in higher atmospheric layers. But this is not always so. By contrast, the temperature usually decreases with height in the Troposphere, but remains constant during some height above the Tropopause (11Km--> T=-50ºC). In the Stratosphere the temperature is increased untill the Stratopause (50Km--->T=+10ºC). Above of here, the temperature suffers increasings and decreasings, for instance reaching 1000ºC in the Termosphere (400Km).
Why the temperature does not decrease always with the height? Well, there are some physical criterions which enhance the stability of a hotter mass of air above another cooler. These stability criterions are derived from the Hidrostatic's equations. But you can imagine it like a balloon filled with hotter air crashing into the roof of your room that avoids its elevation.
Last edited:
• #3
36
0
why does that temperature decrease with height commonly
• #4
lakshmi,
Your first question, Entropy is called as the degree of randomness, randomness means the fredom. matter always opt to be more random hence it is used to define the state of matter.
2. fall in temprature with height is due to the Charles law, it states that with change in pressure or volume or both temprature also changes (this is converse of actual law). Hence with increse in height both pressure and density of the air decreases which results in low temprature.
• #5
Clausius2
Gold Member
1,435
5
lakshmi said:
why does that temperature decrease with height commonly
I've never seen such impolite person. I've just explained that to you just before, and you answer with such bad manners.
• #6
LURCH
2,549
118
I don't think he was being rude, he simply re-phrased his question. He asked why temp gets colder at higher altitude, and you answered that it doesn't allways do so, so he asked why does temp usually gets colder at higher altitude, thus making the question more precise.
Lakshmi, if it helps at all, you can think of entropy as the movement of energy from places where there's more to places where there's less. It's the reason a hot cup of coffee cools down in a normal-temperature room, and warms up the room a little bit while doing so. The cup gets cooler, and the room gets warmer, untill the two are the same temperature, and then the process stops. Of course, entropy itself never stops, just the flow of heat energy from the cup to the room. The room is still radiating heat out to the rest of the universe.
Keeping in mind that matter is just energy in its "condensed" form, you acn see that this principle applies to absolutely every physical phenomenon. Stars lose mass by converting matter to energy in a fusion reaction, this energy is radiated otu into space, slightly warming the temperature of the space between the stars, while taking energy away from the stars themselves. It's all a moving of energy from where there's a lot to where there's not.
• #7
Clausius2
Gold Member
1,435
5
LURCH said:
I don't think he was being rude, he simply re-phrased his question. He asked why temp gets colder at higher altitude, and you answered that it doesn't allways do so, so he asked why does temp usually gets colder at higher altitude, thus making the question more precise.
Lakshmi, if it helps at all, you can think of entropy as the movement of energy from places where there's more to places where there's less. It's the reason a hot cup of coffee cools down in a normal-temperature room, and warms up the room a little bit while doing so. The cup gets cooler, and the room gets warmer, untill the two are the same temperature, and then the process stops. Of course, entropy itself never stops, just the flow of heat energy from the cup to the room. The room is still radiating heat out to the rest of the universe.
Keeping in mind that matter is just energy in its "condensed" form, you acn see that this principle applies to absolutely every physical phenomenon. Stars lose mass by converting matter to energy in a fusion reaction, this energy is radiated otu into space, slightly warming the temperature of the space between the stars, while taking energy away from the stars themselves. It's all a moving of energy from where there's a lot to where there's not.
I'm desiring that Lakshmi write to you something as an acknowdegement more than re-phrasing again his question. Let's see....
• #8
36
0
i am soory clausius but i didnt get satisfactory answer from you :shy:
• #9
Clausius2
Gold Member
1,435
5
Cheers! He spoke.
And what do you think this forum is? It is of a well-given-birth person to acknowledge any response, in spite is statisfactory for you or not. This is not a supermarket where you buy responses.
Ended. You don't need to be worried. Doesn't matters.
• #10
pervect
Staff Emeritus
9,906
1,087
lakshmi said:
2)why does the temperature decreases with increase in altitude
http://farside.ph.utexas.edu/teaching/sm1/lectures/node55.html
does a pretty good job of explaining the "adiabatic atmosphere". This sort of atmosphere gives a decreasing temperature with height.
Note that adiabatic means "no heat transfer", so the adiabatic gas law is the pressure volume relationship that is obtained when a gas is thermally isolated from it's surroundings.
Imagine a packet of air which is being swirled around in the atmosphere. We would expect it to always remain at the same pressure as its surroundings, otherwise it would be mechanically unstable. It is also plausible that the packet moves around too quickly to effectively exchange heat with its surroundings, since air is very a poor heat conductor, and heat flow is consequently quite a slow process. So, to a first approximation, the air in the packet is adiabatic. In a steady-state atmosphere, we expect that as the packet moves upwards, expands due to the reduced pressure, and cools adiabatically, its temperature always remains the same as that of its immediate surroundings. This means that we can use the adiabatic gas law to characterize the cooling of the atmosphere with increasing altitude. In this particular case, the most useful manifestation of the adiabatic law is
$$p^{1-\gamma} T^\gamma = constant$$
I'm afraid I don't quite understand which of these assumptions fails at large altitudes - if you read the earlier section of the URL that I didn't quote, it's probably either the "air is transparent" or the "air is thoroughly mixed" assumption.
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https://upcommons.upc.edu/browse?rpp=20&offset=20&etal=-1&authority=bdf0d3dd-e737-4cc5-9a0e-4299547b5f5d%3Borcid%3A0000-0003-2821-9912&sort_by=-1&type=author&order=ASC
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Now showing items 21-27 of 27
• #### Parameter estimation: online calibration
(Springer, 2017)
Part of book or chapter of book
Restricted access - publisher's policy
This book presents a set of approaches for the real-time monitoring and control of drinking-water networks based on advanced information and communication technologies. It shows the reader how to achieve significant ...
• #### Parameter uncertainty modelling in water distribution network models
(Elsevier, 2015)
Conference report
Open Access
The use of water distribution network (WDN) models is an extended practice [13]. Confidence on decisions taken upon such models depends highly on their accuracy [11]. The parameters uncertainty has to be defined in order ...
• #### Parameterization and sampling design for water networks demand calibration using the SVD : application to a real network
(2014)
Conference report
Open Access
The availability of a good hydraulic model increases the reliability of the results of methodologies using it. Thus, the calibration of the model is a previous step that has to be done. The most uncertain parameters of the ...
• #### Pressure control of a large scale water network using integral action
(2012)
Conference report
Restricted access - confidentiality agreement
This paper presents a study of the e ect of performing di erent control structures on a large scale water network. The aim is to keep network pressures stable and to their minimum in order to increase network efficiency ...
• #### Programa EPANET: La simulación en el análisis del comportamiento hidráulico
(Grupo Tecnipublicaciones, 2014-02)
Article
Restricted access - publisher's policy
En el marco de una tesis doctoral, se ha desarrollado un software que incluye diversos módulos para la simulación, control y calibración de redes de distribución de agua. Este software tiene una finalidad docente con ...
• #### Sensitivity analysis for sampling design and demand calibration in water distribution networks using the singular value decomposition
(2015-10-01)
Article
Open Access
Research in water distribution networks during recent decades has often focused on calibration. There is no unique solution for this problem as the methodologies are developed depending on which parameters have to be ...
• #### Teaching automatic control and modelling through a real application: water distribution networks
(2014-06-03)
Audiovisual
Open Access
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https://www.arxiv-vanity.com/papers/1502.05976/
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# On Supersymmetry, Boundary Actions and Brane Charges
Lorenzo Di Pietro, Nizan Klinghoffer and Itamar Shamir
Weizmann Institute of Science
Rehovot 76100, Israel , , .
###### Abstract:
Supersymmetry transformations change the Lagrangian into a total derivative . On manifolds with boundaries the total derivative term is an obstruction to preserving supersymmetry. Such total derivative terms can be canceled by a boundary action without specifying boundary conditions, but only for a subalgebra of supersymmetry. We study compensating boundary actions for supersymmetry in 4d, and show that they are determined independently of the details of the theory and of the boundary conditions. Two distinct classes of boundary actions exist, which correspond to preserving either a linear combination of supercharges of opposite chirality (called A-type) or supercharges of opposite chirality independently (B-type). The first option preserves a subalgebra isomorphic to in 3d, while the second preserves only a 2d subgroup of the Lorentz symmetry and a subalgebra isomorphic to in 2d. These subalgebras are in one to one correspondence with half-BPS objects: the A-type corresponds to domain walls while the B-type corresponds to strings. We show that integrating the full current algebra and taking into account boundary contributions leads to an energy-momentum tensor which contains the boundary terms. The boundary terms come from the domain wall and string currents in the two respective cases.
preprint: WIS/02/15-FEB-DPPA
## 1 Introduction
The problem of preserving supersymmetry on space-time manifolds with boundaries has a long history in the literature. Most notably it has been extensively studied in the context of open strings and D-branes (see for instance [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]). Much attention was also given to the study of supergravity in spaces with boundaries. This includes applications to the strong coupling limit of heterotic string theory [12], supersymmetric Randall-Sundrum models [13] and general study of supergravity in various dimensions [14, 15, 16, 17, 18].
In field theory, a classification of the half-BPS supersymmetric boundary conditions (BC) for Super Yang-Mills was obtained in [19], and the behavior of these BC under S-duality was analyzed in a subsequent paper [20]. With fewer supersymmetries, the general BC and their interplay with dualities are still largely unexplored. (See [21, 22, 23] for the 3d case.)
Furthermore, recently there has been a great progress, initiated in [24, 25, 26], in understanding how supersymmetry can be preserved on curved manifolds. Advances in localization suggest that partition functions factorize on some curved backgrounds, and the factors have the interpretations of partition functions on manifold with boundaries (see for instance [27, 28, 29]). Motivated by this set of questions, in this paper we consider theories on a 4d space-time with a boundary.
A supersymmetric Lagrangian transforms under supersymmetry into a total derivative . When there is a boundary, the variation of the action is a boundary term
δ∫ML=∫∂MVn . (1.1)
Here is space-time, is the normal to the boundary and . We will consider this as the basic obstruction to preserving supersymmetry. We will show how to construct boundary Lagrangians for which so that
δ(∫ML+∫∂MΔ) =0 . (1.2)
In this way we can construct actions which are invariant under supersymmetry, independently of the choice of BC. This idea was suggested by several authors [15, 30, 31, 32, 33, 34, 35, 36]. In this paper we explore this idea systematically for in 4d.
Let us demonstrate how this works in an example, given by [35] (see also [36]). Consider a superpotential, which comes from a chiral multiplet with supersymmetry variations
δw=√2ζψw , (1.3) δFw=√2i¯ζ¯σμ∂μψw .
Clearly is a supersymmetric bulk action. We can use as a compensating boundary Lagrangian if we restrict to variations for which . This defines a subalgebra isomorphic to in 3d. It follows that
∫MFw+i∫∂Mw (1.4)
is invariant under this subalgebra without using BC.
We see in this example that is exact only with respect to a subalgebra of the supersymmetry transformations. This corresponds to the fact that we cannot preserve all the supersymmetries of the bulk theory. Importantly, we note that the boundary action follows only from the structure of the chiral multiplet. It is independent of the details of the theory and of the specific BC we choose.
This universality of the boundary action is the first of the two central points of this paper. Focusing on 4d it is possible to classify all the ’s which solve for any supersymmetric Lagrangian. This leads to a classification of the subalgebras that can be preserved in this way. We obtain that they are isomorphic to one of the following
1. in 3d : by preserving a linear combination of the supercharges and of opposite chirality. This breaks the -symmetry.
2. in 2d : by preserving a single component of each chirality independently together with the -symmetry and breaking to 2d Lorentz symmetry on the boundary.
3. in 2d : the intersection of the two options above.
Option (1.) corresponds to the solution of [35, 36], while (2.) is to the best of our knowledge novel. They are related by dimensional reduction to the familiar - and -type branes in in 2d [1, 2]. The third subalgebra is the intersection of the first two. It comes about if we introduce two terms in the boundary action, each preserving only one of the two subalgebras above. In each case, after the boundary action is introduced, one can have various choices for BC which are compatible with the preserved subalgebra.
Interestingly, the conditions under which the boundary Lagrangians are well-defined operators are exactly the same as the criteria in [37] for the existence of certain supersymmetric multiplets of the energy-momentum tensor. For example, for Abelian gauge theories with a Fayet-Iliopoulos (FI) term the A-type boundary Lagrangian is not gauge invariant. In these theories, the Ferrara-Zumino (FZ) multiplet of the energy-momentum tensor is not defined. Similarly, a theory must have a preserved -symmetry in order to construct the B-type boundary action. Exactly in this case one can define the -multiplet of the energy-momentum tensor. Moreover, the subalgebras above are in one-to-one correspondence with those preserved by BPS domain walls (case 1.) strings (2.) or both (3.). In fact, we will see that there is a relation between the boundary Lagrangian and the brane charges appearing in the supersymmetry algebra. These in turn are related to the multiplets of the energy-momentum tensor [38].
However, it is important to note that the failure of a certain boundary action to exist does not immediately lead to obstructions on preserving the subalgebras above in presence of the boundary. This is because it may be possible to choose appropriate BC that make the operators in the boundary Lagrangian well-defined (we will give an example of how that can happen in the main body). It only represents an obstruction to preserve supersymmetry independently of the choice of BC.
The relation between a nontrivial and brane charges in the algebra has been known for a long time [39]. These brane charges appear in the supersymmetry variation of the supercurrent as follows
{Qα,¯S˙αν} =2σμα˙α(Tμν+Cμν)+… , (1.5) {Qα,Sβρ} =σμναβCρμν+… ,
where and are the supercurrents, is the string current, is the domain wall current and the ellipses are Schwinger terms. If is exact with respect to a certain subalgebra, then all the brane currents which do not respect this subalgebra must drop. For A-type (B-type) the string (domain wall, respectively) current must vanish up to Schwinger terms. The non-vanishing brane current contributes a boundary term when the current algebra is integrated. We will show that it gives exactly the correct boundary action.111This bears some resemblance to partial supersymmetry breaking in [40]. It would be interesting to explore the relation with anomaly inflow and generalized symmetries, see for example [41, 42].
The interpretation of the boundary actions as arising from brane charges together with the relation to the FZ- and -multiplets is the second key point of the paper. It is our hope that this understanding will facilitate the study background supergravity in theories defined on a manifold with a boundary.
The remainder of the paper is organized as follows. In section 2 we will review the basics of symmetries in quantum field theories with a boundary and explain the idea of compensating boundary actions. In section 3 we focus on in 4d and explain how to construct boundary actions. In section 4 we show that these results can be interpreted in terms of the brane currents of supersymmetry.
## 2 On Symmetries and Boundaries
In this section we review some basic aspects of theories with boundaries and symmetries. In particular we discuss compensating boundary Lagrangians, and emphasize that they give rise to improvements of certain symmetry currents.
Consider a space-time with a boundary . (The convention for the metric is mostly plus.) The boundary is specified by an outward normal vector which is normalized to unit length. Only cases in which is a constant space-like vector are discussed in this paper. We use the index for coordinates in the bulk and for coordinates on the boundary.222We use as an index in the obvious way . We will also consider constant time slices, which we denote by . The index is designated for coordinates on and for its boundary (see figure).
The theories we consider are specified by a 4d bulk action and possibly also a 3d boundary action . Taking the variation we get
δ(S+S∂M) =∫M(∂L∂Φ−∂μ∂L∂(∂μΦ))δΦ+∫∂M(∂L∂(∂nΦ)δΦ+δL∂M) . (2.1)
Here represents all the fields in the theory. The BC are relations of the form
G(Φ,∂nΦ)|∂M=0 , (2.2)
and stationarity of the action on the equations of motion requires that
(∂L∂(∂nΦ)δΦ+δL∂M)∣∣ ∣∣G=0=∂^μ(…) . (2.3)
For simplicity we are not including additional dynamical fields on the boundary.
Symmetries are transformations of the fields which leave the action invariant. (We denote symmetry variations with to distinguish from generic variations .) When there are no boundaries, a symmetry is required to satisfy
δsymL =∂μVμ . (2.4)
By Noether’s theorem this implies the existence of a current333 We choose this rather unconventional sign of for consistency with the conventions of [37] and [38] for the supercurrent and the energy-momentum tensor.
Jμ =−∂L∂(∂μΦ)δsymΦ+Vμ (2.5)
satisfying on-shell. This implies that is time independent. (2.5) is said to be the canonical form of the current.
Suppose now that there is a boundary, and a transformation satisfying (2.4) is given. In this context, may be called a bulk symmetry. Under what conditions does this lead to the implications of a symmetry? Let us mention two aspects of this problem.
Firstly, the time-derivative of the charge contains a boundary term
∂0Q=−∫∂ΣJn . (2.6)
This means that the conservation may fail because charge can leak through the boundary. The equation is usually emphasized as the basic requirement of the BC for preserving the symmetry. A different starting point is to demand that the BC (2.2) are invariant under the symmetry transformation, a criterion that we call symmetric BC. This amounts to imposing444For space-time symmetries such as supersymmetry which acts with derivatives on fields, we can only demand that (2.7) holds up to equations of motion.
δsymG|G=0 =0 . (2.7)
We will explain below how this leads to the existence of a conserved charge. This condition was discussed by several authors (see for instance [2, 5, 6, 8, 9]), mainly as a consistency requirement for supersymmetric BC.
Secondly, in presence of a boundary, a bulk symmetry gives rise to a boundary term in the variation of the action
δsym(S+S∂M)=∫∂MVn+∫∂MδsymL∂M . (2.8)
This obstruction to the invariance of the action can be removed without invoking the BC (or rather a priori to fixing the BC), by choosing a boundary term which cancels the bulk variation.555Of course, if we assume that the BC are symmetric then it follows from the stationarity of the action (2.3) that the boundary term vanishes on-shell.
Notably, these two aspects are related because the boundary term that cancels (2.8) appears in the stationarity condition (2.3), in a way which makes it consistent with symmetric BC. Before coming to this point, we proceed to show how symmetric BC lead to vanishing flux.
### 2.1 Constructing Conserved Charges
It follows from (2.6) that the charge is conserved if and only if, for our choice of BC, the normal component of the current is a total derivative on , i.e.
Jn|∂Σ=∂^aK^a (2.9)
for some (recall ). Let us show how this is obtained from symmetric BC.
Consider a bulk symmetry as in (2.4). Using the equations of motion we can write the variation of the bulk action as
δsymS|on−shell=∫∂M∂L∂(∂nΦ)δsymΦ . (2.10)
Note that this is valid only if belongs to the field variations which are allowed by the BC, i.e. we have to consider symmetric BC. Comparing this with (2.4) we get that
Jn|∂M=∂^μK^μ (2.11)
for some (recall ). This looks very similar to the condition (2.9), but not quite since it includes a time derivative and so does not vanish when integrated on . This is easily corrected.
One modifies the definition of the charge by including a boundary term
Q′ =∫ΣJ0+∫∂ΣK0 . (2.12)
It is easy to check that . In fact, this can be understood as an improvement of the current. We can find an anti-symmetric tensor such that . One then constructs an improved current
J′μ =Jμ+∂νLμν (2.13)
for which and . Let us stress that it is the canonical current (2.5) which is improved here.
### 2.2 Compensating Boundary Lagrangians
We now turn to a discussion of the boundary terms that can be added to make the action invariant under a symmetry transformation. This idea was first applied to supersymmetry a long time ago [30, 31]. More recently it was expounded by Belyaev and van Nieuwenhuizen [15, 35, 43]. (See also [21, 34, 36].)
Suppose that there exists a such that
Vn+δsymΔ=∂^μK^μ . (2.14)
In other words is exact in the symmetry variation, up to a total derivative on the boundary. Then adding ensures that the action is invariant without reference to BC. We call a compensating boundary Lagrangian.
Beyond the compensating term we have the freedom to add any symmetric boundary action, i.e. a term which is invariant by itself. (Note that is only defined up to such “closed” terms.) This leads to the general form
S+∫∂MΔ+∫∂ML′∂M , (2.15)
where .
We can use the form of the action in (2.15) to determine explicitly the required improvement which corresponds to a conserved charge. Let us assume for simplicity that the boundary Lagrangian consists only of the compensating term . Note that equation (2.3) holds with if we have symmetric BC. Then, using (2.3) and (2.14), we find666We consider a case where the total derivative in (2.3) vanishes for simplicity.
Jn|∂M =−∂L∂(∂nΦ)δsymΦ+Vn=∂^μK^μ . (2.16)
If one introduces in addition a boundary term as in (2.15) then the effect is to change (2.16) by .
Note that, with a compensating boundary Lagrangian, the stationarity condition is manifestly consistent with symmetric BC. This suggests that it is always sufficient to consider actions adhering to the form (2.15). One should keep in mind that it is possible to add a boundary term which vanishes trivially on the BC and is not symmetric. The claim is modulo such terms. The mismatch goes also in the other direction. Given an action of the form (2.15), it may be possible to choose BC which are not symmetric but still respect the stationarity condition of the action.
Let us now summarise the discussion above by the following comments. We emphasize that in what follows we will not attempt at finding general solutions of , rather we will focus on equation (2.14). The point is that while there are many solutions of , the possible solutions of (2.14) are finite, each corresponding to a whole family of BC. Moreover, the ’s which solve (2.14) are universal in that they are determined independently of the theory and of the BC.
### 2.3 The Energy-Momentum Tensor
Let us look closer at the case of translational symmetries, specified by a constant vector . Since the Lagrangian is a scalar, it follows that . This gives rise to the canonical energy-momentum tensor
ϵνˆTνμ =ϵν(−∂L∂(∂μΦ)∂νΦ+δμνL) . (2.17)
Here the index is the direction of the translation, and is the current index (i.e. ) with respect to which it is conserved. In this convention and . In general, the canonical energy-momentum tensor is not symmetric. We will use a hat to distinguish it from the symmetric energy-momentum tensor.
Now suppose that there is a boundary. This explicitly breaks translations for which . For the remaining translations with we have that and thus they do not require compensating boundary actions.
Suppose that the definition of the theory includes a boundary Lagrangian . If a translation by is preserved, we must have that . As explained above, this implies an improvement of . The precise form depends on , and is necessarily not symmetric (unlike the canonical current which can always be symmetrized). This is linked with the breakdown of Lorentz invariance ensued by the boundary.
In the discussion above it is important to notice that the energy-momentum tensor that we are improving is the canonical one. This will be important for us because in the context of supersymmetry one usually considers multiplets in which the energy-momentum tensor is symmetric. We will have to take this discrepancy into account.
## 3 Boundary Actions in Supersymmetry
In this section we shall begin our investigation of supersymmetry. The basic constraint on the supercharges that can be preserved in flat space with boundaries arises because supersymmetry transformations anti-commute to translations, some of which are inevitably broken by the boundary. This implies that only a subset of the supersymmetries can survive in presence of boundaries.777Note that on curved manifolds it is sometimes possible to introduce a boundary without breaking any of the supersymmetries preserved by the background. This is because in general the Killing vectors associated to the isometries that appear on the r.h.s. of the supersymmetry algebra on curved space do not form a basis of the tangent space (see for instance [25]). Therefore, one can introduce a boundary that is left invariant by all the isometries appearing in the algebra.
Focusing on the case of supersymmetry in 4d, there are two maximal subalgebras that can be preserved, one isomorphic to in 3d and the other one to in 2d. These options correspond to the possible compensating boundary actions that one can construct. We shall refer to these two cases as A-type and B-type respectively. We find these names appropriate because they are related by dimension reduction to the BC in in 2d bearing the same name. Note that in the case of B-type the 3d Lorentz invariance on the boundary is broken by the boundary action.
In supersymmetry in 4d there are two ways to build bulk actions. One can construct a supersymmetric Lagrangian as the -component of a real multiplet or as the -component (-component) of a chiral (anti-chiral) superfield. The basic idea is to use the other bosonic fields in the multiplet to construct compensating boundary terms. We will see below that this follows straightforwardly from the supersymmetry variations which relate the components of the multiplet.
We will use the conventions of [44], except that we take the Killing spinors and to be commuting.
### 3.1 A-type Boundary Actions
This is the solution given by Belyaev and van Nieuwenhuizen [35] and later elaborated by Bilal [36], which we now review. (A 2d analogue can be found in [3, 45].) In addition, we derive the improvement which follows from the -term action. It will play an important role in section 5.
Let us begin by recalling the example which appeared in the introduction, i.e. the compensating term for the superpotential. The supersymmetric Lagrangian comes from the -component of a chiral multiplet . As explained before, it follows from the structure of the chiral multiplet that the boundary term is
δ¯ζ∫MFw=√2i∫∂M¯ζ¯σnψw . (3.1)
To obtain the compensating action we restrict to a subalgebra defined by the relation . If the theory has an -symmetry we can set (as assumed in the introduction for simplicity), otherwise it is a free parameter. Equivalently, we consider supercharges which take the form
˜Qα=1√2(e−iγ/2Qα+eiγ/2(σn¯Q)α) . (3.2)
The supersymmetry transformations thus generated are denoted by . The supercharges satisfy the reality condition
(σn˜Q†)α=˜Qα . (3.3)
The bulk action supplemented by the boundary term is
SF,A−type=∫MFw+ieiγ∫∂Mw . (3.4)
One can verify that with no information assumed about the value of on the boundary. Note that the boundary action breaks -symmetry explicitly. The subalgebra we obtained is in fact isomorphic to supersymmetry in 3d
{˜Qα,˜Qβ}=2(Γ^μ)αβP^μ , (3.5)
where we defined the 3d gamma matrices by (recall that ), so that . Only momenta tangent to the boundary appear in this algebra.
We are now ready to consider the -term action. As noted above, the -term resides in a real multiplet whose components are . They are related by the following transformations
δC=iζχ−i¯ζ¯χ , (3.6) δχα=ζαM+(σμ¯ζ)α(ivμ+∂μC) , δ¯χ˙α=¯ζ˙α¯M+(¯σμζ)˙α(ivμ−∂μC) , δM=2¯ζ¯λ+2i¯ζ¯σμ∂μχ , δ¯M=2ζλ+2iζσμ∂μ¯χ , δvμ=iζσμ¯λ+i¯ζ¯σμλ+∂μ(ζχ+¯ζ¯χ) , δλα=iζαD+2(σμνζ)α∂μvν , δ¯λ˙α=−i¯ζ˙αD+2(¯σμν¯ζ)˙α∂μvν , δD=−ζσμ∂μ¯λ+¯ζ¯σμ∂μλ .
The top component is a bulk supersymmetric Lagrangian. Restricting as above to the supercharges we arrive at the following formula for the -term action supplemented by boundary terms
SD,A−type=∫MD+12∫∂M(e−iγM+eiγ¯M)+∫∂M∂nC . (3.7)
It is important to note that, unlike the previous case, the boundary terms compensate the bulk variation up to a total derivative on the boundary. Explicitly, we have that
Vn+˜δ(e−iγM+eiγ¯M2+∂nC)=i∂^μ(e−iγ¯ζ¯σ^μχ+eiγζσ^μ¯χ) . (3.8)
The significance of this was explained in section 2; a specific improvement of the canonical current is required in order to get a conserved supercharge. Using again the relation , we find that the improvement of the canonical supercurrent is
ζ˜Sμ→ζ˜Sμ−2i∂ν(ζσμνχ−¯ζ¯σμν¯χ) . (3.9)
There is a relation between the -term boundary action and -term boundary action. This comes about because a -term Lagrangian can always be written as a superpotential up to boundary terms. More precisely, given a real superfield , we can define a chiral superfield , whose -component is and bottom component is . Using expression (3.4) for the -term action with the boundary term, combined with the complex conjugate, leads exactly to the action (3.7).
### 3.2 B-type Boundary Actions
We have presented above the construction of compensating boundary actions which correspond to the 3d subalgebra. It is natural to ask if it is possible to preserve supercharges of opposite chirality in an independent way, thus also preserving the -symmetry. Naively the answer to this question appears to be negative: on the boundary we expect to find a supersymmetry algebra with 2 supercharges and the only candidate seems to be the 3d algebra, whose supercharges are real Majorana fermions and which has no -charge. However, this line of reasoning includes the assumption that 3d Lorentz invariance is maintained.
Relaxing this assumption, we are allowed to preserve only one component of and one of . This is implemented by choosing Killing spinors and .
Without loss of generality we will place along one of the axes, by choosing . Let us consider again the -term action. The variations are written as
δ∫MD =−∫∂Mζσ2¯λ and¯δ∫MD =∫∂M¯ζ¯σ2λ . (3.10)
To find compensating boundary actions we choose the Killing spinors and , which satisfy the identities and . Using (3.6) we then find that a B-type modified -term is given by
(3.11)
It is easy to check that this boundary action does not lead to a time derivative on the boundary, so no improvement of the canonical current is needed. The boundary action can also be written as a bulk term with . This makes manifest the invariance under shifts of by a total derivative.888One might wonder whether it is possible to preserve two supercharges corresponding to the two components of , while breaking (or viceversa). Indeed one can see from (3.6) that an additional possibility for the -term compensating boundary action exists
(3.12)
which exactly corresponds to preserving only . (Preserving would be achieved by changing the sign of the boundary term.) This subalgebra is not compatible with the requirement that , which is satisfied in Lorentzian signature, and therefore we reject this possibility. The clash with unitarity is reflected in the boundary action being not real.
The boundary action explicitly breaks the three dimensional Lorentz invariance by picking a preferred direction on the boundary. We remain with 2d Lorentz invariance in the plane. Defining and the preserved subalgebra is
{Q−,¯Q−}=2(P0+P3) . (3.13)
This subalgebra is isomorphic to supersymmetry in the two dimensions spanned by and . Changing the sign of the boundary action in (3.11) changes the 2d chirality leading to instead.
We now explain how to find B-type compensating boundary action for an -term bulk Lagrangian. To this end, we will see that it is necessary to invoke the existence of an -symmetry. Moreover, differently from all the previous cases, in this case the cancellation of the boundary term will rely on the equations of motion. (It is however independent of the choice of boundary conditions.) For definiteness, we focus on a (-symmetric) superpotential in a Wess-Zumino model.
Consider then a set of chiral fields of -charges , a Kähler potential and a superpotential . The equations of motion are given by
¯D2∂aK=4∂aW . (3.14)
The superpotential must have -charge 2 in order to preserve the -symmetry, i.e. it must satisfy the constraint
∑aRaΦa∂aW=2W . (3.15)
Likewise, the -neutrality of the Kähler potential means that
∑aiRa(Φa∂aK−¯Φ¯a∂¯aK)=0 (3.16)
(up to a Kähler transformation which we disregard for brevity). One can then define a real multiplet by
V′=12∑aRaΦa∂aK . (3.17)
Using the equations of motion one obtains , which leads to the relation . We saw in the study of the -term that the variation of is compensated by adding on the boundary; gives rise to an additional boundary term. Hence, we obtain the following form for the -term and the relative compensating boundary Lagrangian
SF,B−type=∫M(Fw+¯F¯w)+∫∂M(∂nC′+v′1) . (3.18)
To find the corresponding improvement it is useful to note that the fermionic fields of and are related by . This leads to
Vn=√2i¯ζ¯σnψw=−¯δ(∂nC′+v′1)−2i¯ζ¯σnμ∂μ¯χ′ , (3.19)
and similarly for the variation. We then find that the supercurrents should be improved according to
ζSμ→ζSμ−2iζσμν∂νχ′ ,¯ζ¯Sμ→¯ζ¯Sμ+2i¯ζ¯σμν∂ν¯χ′ . (3.20)
### 3.3 Discussion
We would now like to look closer at the boundary actions obtained above, focusing on the cases of a Wess-Zumino model and a gauge theory. This will expose an intriguing relation to the supersymmetry multiplets of the energy-momentum tensor. Requiring that the boundary actions are well-defined presents nontrivial constraints on the underlying field theory, which will be shown to be equivalent to the existence of those multiplets.
For a Wess-Zumino model the -term Lagrangian comes from the real superfield . The A-type compensating boundary Lagrangian for this -term contains the term . This makes sense only if the Kähler potential is well-defined up to an additive constant. Equivalently, the Kähler connection
−i2(∂aKdΦa−∂¯aK∂¯Φ¯a) (3.21)
must be globally well-defined. Note that this is never the case if the target space is compact.
Another example comes from the Fayet-Iliopoulos term (FI) in Abelian gauge theories. The real superfield associated to such a -term action is the elementary Abelian vector superfield. Its bottom component is shifted by an arbitrary real function under a gauge transformation, making the would-be compensating action not gauge invariant.
On the contrary, the B-type boundary action (3.11) for the -term is not affected by any ambiguity in the examples that we have just considered. Both under Kähler transformations in the Wess-Zumino model, and under gauge transformations in the gauge theory with an FI term, the boundary Lagrangian changes into a total derivative on the boundary; hence the action is well-defined. On the other hand, we showed that the construction of the B-type boundary actions requires the existence of an -symmetry. (Note that without a superpotential there is always an -symmetry that assigns charge 0 to all the chiral superfields.)
When the boundary Lagrangian does not exist in some theory, it is not possible to obtain a total action that is invariant under the associated subalgebra independently of the BC. Let us stress that this does not mean that the subalgebra cannot be preserved in this theory. This is because we also need to specify some BC to fully define the theory, and it may be possible that the boundary operator becomes well-defined (or vanish altogether) when evaluated on the BC.
An example will help clarify this issue. Consider a single chiral superfield , whose components we denote by , with a canonical Kähler potential . Suppose we identify , i.e. we take the target space to be cylinder. In this case the Kähler form (3.21) is not globally well-defined, and the term in the boundary action is not a well-defined operator. Nevertheless, consider the following BC
ϕ =¯ϕ , (3.22) ∂nϕ =−∂n¯ϕ , ψ =σn¯ψ .
Note that these BC respect the identification on the target space. A short computation reveals that the BC are symmetric with respect to the subalgebra given by the relation , i.e. an A-type subalgebra. Consistently, note that the boundary action vanishes identically when evaluated on (3.22). This means that given the BC (3.22) the boundary term is not required for the stationarity of the action, and hence it is redundant.
Bearing in mind this caveat, we note that the conditions that allow to define the A-type and B-type boundary actions are in one-to-one correspondence with those found by [37] for the existence of the FZ- and -multiplets, respectively. These are supersymmetric multiplets of operators that include the energy-momentum tensor. This relation will be elucidated in the next section by a calculation of the current algebra in Wess-Zumino models. In preparation for the next section, let us discuss some relevant aspects of the supercurrent multiplets and their expression in Wess-Zumino models.
The basic fact is that both the FZ-multiplet and the -multiplet can only be defined in a restricted class of 4d supersymmetric field theories. A third, larger multiplet which exists in general was introduced in [37] and dubbed -multiplet. The FZ-multiplet and the -multiplet are naturally embedded into the -multiplet. When either of the two shorter multiplets is defined, it can be obtained from the -multiplet via an improvement transformation (that sets to zero some of its components). A short review of the -multiplet and its improvements is given in appendix A.
In Wess-Zumino models, given a Kähler potential and a superpotential the -multiplet is given by
Sα˙α=2∂a∂¯aKDαΦa¯D˙α¯Φ¯a , (3.23) χα=¯D2DαK , (3.24) Yα=4DαW .
Using the improvement (A.13) we can set if we choose , and we reduce to the FZ-multiplet. This is an allowed improvement only if the Kähler potential is well-defined up to an additive constant. On the other hand, to obtain the -multiplet we must demand that the theory has an -symmetry. Similarly to the comments in the previous section, when this is the case is a real multiplet and the equations of motion imply that . The improvement by sets and gives the -multiplet, whose bottom component is the conserved -current.
It is interesting to compare the improvements of the supercurrent which are implied by the above choices of with the improvements (3.9) and (3.20) coming from the compensating boundary actions. Consider first the -multiplet, compared to the improvement that results from the B-type superpotential. Looking at the -component of , we see that the improvement which follows from the -multiplet turns out to be twice the B-type improvement (3.20). We will have to wait until the next section to see how this discrepancy is resolved. It will turn out that the -multiplet formulas have to be modified due to boundary effects.
Now consider the case with well-defined FZ-multiplet and compare to the improvement for the A-type boundary action. We obtained the A-type compensating boundary action for the -term by first rewriting the -term as an integral over only half superspace, and then applying the result for the -term. The resulting -term for a Wess-Zumino model comes from the chiral superfield . Therefore, we have to improve in such a way that
Yα=4DαW→Dα(4W−12¯D2K) . (3.25)
This correspond to an improvement with . (Note that this is different from the improvement that sets to .) Comparing to the improvement that was obtained from the A-type boundary action (3.9), we find again the same discrepancy by a factor of 2.
## 4 Boundary Actions and Brane Charges
In this section we will show that the compensating boundary actions can be interpreted in terms of brane charges of the supersymmetry algebra in 4d. From this point of view, a supersymmetric boundary is analogous to a BPS extended object. The algebra admits two kinds of half-BPS extended objects, namely domain walls and strings, (and quarter-BPS configurations obtained by combining the previous two, i.e. domain wall junctions) [46, 47, 48, 49]. As we will see, they correspond to A-type and B-type compensating boundary actions, respectively. In order to give a self-contained presentation, we will start by briefly reviewing brane charges and BPS objects (see [50] for more details).
### 4.1 Brane Charges and BPS Branes in N=1 in 4d
The most general supersymmetry algebra in 4d which takes into account brane charges is
{Qα,¯Q˙α} =2σμα˙α(Pμ+Zμ), (4.1) {Qα,Qβ} =σμναβZμν . (4.2)
The structure of the brane charges and is fixed by Lorentz invariance. The real vector is a string charge and the complex two-form a domain wall charge.
The corresponding conserved currents are a two-form current and a three-form current which are related to the charges by
Zμ=∫Σd3xCμ0 , (4.3) Zμν=∫Σd3xCμν0 . (4.4)
In flat space without a boundary the corresponding charge will vanish in any configuration with fields approaching zero sufficiently fast at infinity. This is how one recovers the usual supersymmetry algebra. States carrying brane charges can sometimes be annihilated by a subalgebra of the initial 4d supersymmetry algebra. In this case the brane is called BPS.
For instance, for a domain wall with normal vector , we can go to the rest frame in which , being the energy of the configuration. The brane charge in this frame can be written as
Zμν=2iZϵ0μνρnρ , (4.5)
where is a complex number. and are formally infinite, but the energy and charge per unit volume are finite. Consider the supercharges
˜Qα=1√2(e−iγ/2Qα+eiγ/2(σn¯Q)α) (4.6)
that appeared in (3.2). Computing their anticommutators in the rest frame, we find
{~Qα,~Qβ}=−Γ0αβ(2E−e−iγZ−eiγZ∗)=−2Γ0αβ(E−|Z|) . (4.7)
In the last equality we fixed to cancel the phase of . The reality condition of in (3.3) implies the BPS bound . When , the supercharges annihilate the state of the domain wall, and the configuration is half-BPS.
Note that, if we consider fluctuations around the state of the domain wall, it is natural to consider a shifted momentum
P′^μ=P^μ+|Z|η^μ0. (4.8)
The supercharges then generate an algebra isomorphic to in 3d
{~Qα,~Qβ}=2Γ^μαβP′^μ . (4.9)
Analogous statements hold for the BPS string associated with the charge . In that case we have a real two-form normal to the two-dimensional world-sheet. In the rest frame the charge can be written as
Zμ=−12Zϵ0μνρnνρ (4.10)
for a real constant , and we fixed the normalization so that and . We can introduce the chiral projectors
(P±) βα =12(δ βα∓i(σμν) βαnμν), (4.11) (P†±)˙α ˙β =12(δ˙α ˙β∓i(¯σμν)˙α ˙βnμν) . (4.12)
The anticommutator of the projected supercharges (, ) is
{Q±,¯Q±}=2(E∓Z) . (4.13)
If we take , depending on the sign of the string will be invariant under the supercharges or . Shifting the momentum , the preserved supercharges will generate an algebra isomorphic to in 2d (or for the opposite sign of ). If both domain walls and strings are present, at most a superalgebra isomorphic to the (or ) in 2d can be preserved, and the corresponding state is quarter-BPS.
As we have already stressed, the algebras of the supercharges which are symmetries of the BPS domain wall, or the BPS string, are exactly the same algebras which are preserved by the A-type compensating boundary action, or the B-type, respectively. Indeed, we will see in the following subsections that we can interpret such boundary Lagrangians as brane currents supported on the boundary. Taking this point of view, the shift in the momentum reflects the addition of a new term proportional to to the action (recall that, as discussed in section 2, adding the boundary Lagrangian affects the energy-momentum tensor.) This is the boundary term necessary to obtain an action which is invariant under the preserved algebra. Therefore, this approach will lead to an independent computation of the compensating boundary action, based on the algebra of charges rather than on the variation of the action.
### 4.2 Current Algebra of Supersymmetry and Boundaries
Consider the full current algebra of supersymmetry – the equal time commutation relations of the supercurrents. Schematically, it takes the form
{¯S0˙α(t,y),Sμα(t,x)}=2σνα˙αTνμδ(3)(y−x)+… , (4.14) {S0α(t,y),Sμβ(t,x)}=0+… , (4.15)
where the ellipses represent total derivative terms, usually referred to as Schwinger terms. It is not known in general how to fix the form of all these terms. Note that when there are no boundaries and no extended objects this equation can be straightforwardly integrated to yield the 4d supersymmetry algebra .
Integrating the anticommutators (4.14) only over the coordinate on a fixed time slice, one obtains the anticommutator of the supercharge with the supercurrent operator, known as the half-integrated algebra. When there is no boundary, the result of integrating (4.14) once is universal for any theory in 4d [37]. The following half-integrated current algebra is obtained
{¯Q˙α,Sαμ}=σνα˙α(2Tνμ+2Cνμ−12ϵνμρσ∂ρjσ+i∂νjμ−iηνμ∂ρjρ) , (4.16) {Qβ,Sαρ}=σμναβCρμν .
Here and are respectively the string and domain wall currents introduced above. Besides the brane currents, an additional operator appears in the algebra. The operators in (4.16) form the -multiplet (reviewed in appendix A). Let us emphasize that the energy-momentum tensor in (4.16) is symmetric.
As explained in the appendix A, improvements of the -multiplet are parametrized by a real superfield
U=u+θη+¯θ¯η+θ2N+¯θ2¯N−θσμ¯θVμ+… . (4.17)
Here we follow the conventions of [38]. This leads to improvements of the energy-momentum tensor and the supercurrent given by
Sαμ→Sαμ+∂ν(2σμνη)α , (4.18) Tμν→Tμν+12(∂μ∂ν−ημν∂2)u .
Other operators in the -multiplet transform as
jμ→jμ+Vμ , (4.19) Cνμ→Cνμ+34ϵνμρσ∂ρVσ , (4.20) Cνμρ→Cνμρ+2ϵνμρσ∂σN .
Note that the improvement preserves the symmetry of the energy-momentum tensor. Under such improvements the half-integrated current algebra (4.16) is covariant – it retains its form when the improvements form a multiplet. In some cases, the improvements can be used to set to zero some of the Schwinger terms. If the brane currents can be improved to , the multiplet is reduced to a shorter one. In particular, when the string current is set to 0, the shortened multiplet is the FZ-multiplet, while when the domain wall current is set to 0 we obtain the -multiplet.
Consider now the current algebra for theories with a boundary. We wish to integrate (4.14) carefully taking into account all the total derivative terms. This will introduce contributions in the integrated algebra of supercharges which have the structure of the brane charges in (4.1) and (4.2). In analogy with the BPS states, only a subalgebra which is blind to the brane charges can be preserved. Unlike the case with no boundary, the charges are now sensitive to improvements. We must choose the improvements in such a way that the resulting charges are time independent.
There are several subtleties in realising the idea just presented. Naively, one could just integrate (4.16), with the correct improvement taken into account. However, this does not work for the following reason. The problem is that to obtain (4.16) from (4.14), one needs to integrate some total derivative terms in (4.14). We could set their contribution to zero by choosing appropriate BC. However this approach does not allow us to obtain information about the boundary terms. We wish to remain agnostic about a specific choice of BC and keep track of all the boundary contributions.
The following simple example will help explain how boundary terms appear in the algebra, and their relation to the boundary Lagrangian. Consider a real scalar with a free Lagrangian. The canonical Hamiltonian (density) is given by
T00=12(∂0φ)2+12(∂aφ)2 (4.21)
and the canonical commutation relations by
i[∂0φ(x),φ(y)]=δ(3)(x−y) . (4.22)
If we pick time-translationally invariant BC, generates the symmetry of time translation. Indeed one readily checks that . However, consider also the action of on the canonical momenta. Using the equations of motion we obtain
i[H,∂0φ(x)] =∂20φ(x)−δ(xn)∂nφ(x) . (4.23)
Note the additional term localized on the boundary . Considering the canonical relation
i[∂0φ,⋅]=δδφ(⋅) , (4.24)
we recognize that this boundary term is analogous to the one coming from the variation of the action. Similarly to the latter, also the boundary term in (4.23) must be set to zero by the BC. In this case it is clear that Neumann BC are implied. We can have Dirichlet BC by adding a boundary term to , which leads to
i[H,∂0φ(x)] =∂20φ(x)+∂nδ(xn)φ(x) . (4.25)
Recall that the boundary term affects the Hamiltonian via the improvement of the energy-momentum tensor discussed in section 2. We can see from this simple example how the boundary terms in commutation relations with the Hamiltonian are related to boundary terms in the Lagrangian. This will continue to be true for supersymmetry, albeit in a more convoluted way.
Let us address an objection which might be prompted by the discussion above. We have been using the naive canonical commutation relations, without taking into account how they are modified by the BC. Alternatively, one should first decide on BC and then formulate canonical commutation relations which are consistent with this choice. However, as mentioned before, doing that will prevent us from keeping track of the boundary terms.
We will bypass this problem in the following way. We consider a theory which is defined in infinite flat space, such that the usual commutation relations hold everywhere. Now we focus our attention on a domain inside the infinite time slice . Charges formed by integration on this restricted domain are of course not guaranteed to be conserved, but there is no problem in computing their commutation relations. In this way we can now use the naive commutation relations and keep track of total derivative terms.
### 4.3 Wess-Zumino Model
In this section we consider a Wess-Zumino model with canonical Kähler potential and generic superpotential. We will compute the current algebra explicitly starting from the canonical commutation relations, and use it to show the relation between the brane charge and the boundary action. We work in this setup in order to compute explicitly the boundary terms.
Consider a chiral superfield . The Kähler potential is
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https://www.zora.uzh.ch/id/eprint/45616/
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# Measurement of the charge ratio of atmospheric muons with the CMS detector
CMS Collaboration; Khachatryan, V; Amsler, C; De Visscher, S; Chiochia, V; et al (2010). Measurement of the charge ratio of atmospheric muons with the CMS detector. Physics Letters B, 692(2):83-104.
## Abstract
We present a measurement of the ratio of positive to negative muon fluxes from cosmic ray interactions
in the atmosphere, using data collected by the CMS detector both at ground level and in the underground
experimental cavern at the CERN LHC. Muons were detected in the momentum range from 5 GeV/c to
1 TeV/c. The surface flux ratio is measured to be 1.2766 ± 0.0032 (stat.) ± 0.0032 (syst.), independent
of the muon momentum, below 100 GeV/c. This is the most precise measurement to date. At higher
momenta the data are consistent with an increase of the charge ratio, in agreement with cosmic ray
shower models and compatible with previous measurements by deep-underground experiments.
## Abstract
We present a measurement of the ratio of positive to negative muon fluxes from cosmic ray interactions
in the atmosphere, using data collected by the CMS detector both at ground level and in the underground
experimental cavern at the CERN LHC. Muons were detected in the momentum range from 5 GeV/c to
1 TeV/c. The surface flux ratio is measured to be 1.2766 ± 0.0032 (stat.) ± 0.0032 (syst.), independent
of the muon momentum, below 100 GeV/c. This is the most precise measurement to date. At higher
momenta the data are consistent with an increase of the charge ratio, in agreement with cosmic ray
shower models and compatible with previous measurements by deep-underground experiments.
## Statistics
### Citations
Dimensions.ai Metrics
37 citations in Web of Science®
37 citations in Scopus®
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https://homework.cpm.org/category/CCI_CT/textbook/pc/chapter/4/lesson/4.2.3/problem/4-100
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### Home > PC > Chapter 4 > Lesson 4.2.3 > Problem4-100
4-100.
Verify that $\text{cos }θ + \text{sin }θ \text{ tan }θ = \text{sec }θ$ by simplifying the left side and using the Fundamental Pythagorean Identity.
4. Simplifying using the Fundamental Pythagorean Identities.
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https://chem.libretexts.org/Courses/Grand_Rapids_Community_College/CHM_110%3A_Chemistry_of_the_Modern_World_(Neils)/1%3A_The_Basics_of_Chemistry/1.1_The_Terms_of_Science
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# 1.1 The Terms of Science
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## Six Basic Terms (All definitions arefrom https://www.merriam-webster.com/)
The language of chemistry (and all science) includes terms that specify the validity or degree of certainty of a statement. The following six terms encompass the wide range of certainty that scientist place upon their statements:
Fact – “a thing done; something that has actual existence; an actual occurrence”
Data - (plural) "collected by observation or measurement" What scientists gather as they do experiments. You must remember that although the number you measure is a fact, it may not be a true measure of what you think you are measuring. Also, all data are subject to scrutiny by other scientists (peer review) who may spot errors or inconsistencies. Most data undergoes some type of statistical analysis before it is used.
Assumption – “the supposition that something is true.” Not an observed or measured piece of data or a fact. Scientists use well-grounded assumptions to simplify calculations and to take into account immeasurable quantities. Assumptions can be “good” or “bad” depending on how many facts you have to back them up and show their validity.
Law – “a statement of an order or relation of phenomena that so far as is known is invariable under given conditions; a relation proved or assumed to hold between mathematical or logical expressions; the observed regularity of nature.” How scientists describe quantifiable (measurable) events or processes such as the law of gravity, the law of conservation of matter and Newton’s three laws of motion.
Model – “a description or analogy used to help visualize something that cannot be directly observed; a system of postulates, data, and inferences presented as a description of an object or an event.” What scientists use to describe objects or systems of study such as atomic and molecular structure, chemical reactions, evolutionary changes, patterns of global warming, etc. Models are also useful in predicting likely possible future events. The usefulness of a model depends on the strength of the data and assumptions that are used to create it.
Note
"All models are wrong, but some models are useful." - George Box
Theory – “the analysis of a set of facts in their relation to one another; a plausible or scientifically acceptable general principle or body of principles offered to explain phenomena.” How scientists combine data (facts) and assumptions (well - educated guesses) to describe complex systems of nature such as atomic theory, wave/particle theory of light, evolutionary theory, plate tectonics theory.
Probability –“the mathematical study of the chance that a given event will occur." The true basis for predicting likely possible future events. For instance, chemists gather data,carry out statistical analysis of these data and then determine the probability of a chemical reaction occurring. Probability is also used to create and test models and theories.
All models and theories are subject to constant testing and will be altered or replaced if experimental data expose any flaws.
## The Scientific Method
The Scientific Method is simply a framework for the systematic exploration of patterns in our world. It just so happens that this framework is extremely useful for the examination of chemistry and its many questions. The scientific process, an iterative process, uses the repeated acquisition and testing of data through experimental procedures to disprove hypotheses. A hypothesis is a proposed explanation of natural phenomena, and after a hypothesis has survived many rounds of testing, it may be accepted as a theory and used to explain the phenomena in question. Thus, the scientific method is not a linear process of steps, but a method of inductive reasoning.
### Introduction
In terms of science, the scientific method is a process used to step through the task of examining patterns in the world, forming a hypothesis that explain these patterns, and then gathering data to test the hypothesis. This time tested method has been applied in almost every field of inquiry such as physics, astronomy, chemistry, biology and ecology. "No one person can be credited as the inventor of the scientific method. It was really not invented but recognized and developed as the natural method of obtaining reliable knowledge" (Scientific Method History). Many of the method's attributes can be traced back to the works of Galileo in astronomy, Francis Bacon in philosophy, Robert Boyle in chemistry and physics, and Isaac Newton's work in physics. The goal of a using scientific method is to ultimately establish a natural law, which is a detailed statement about natural phenomena supported by a number of experiments.
### The Scientific Method Explained
Here we will explore examples of how the scientific method is implemented. In reality, the Scientific Method is a complicated process that can take many directions and starting points. It is often referenced to be a iterative/recursive process because "An iterative process is a process for calculating a desired result by means of a repeated cycle of operations. An iterative process should be convergent, i.e., it should come closer to the desired result as the number of iterations increases" (Principia Cybernetica Web). Therefore, scientists often develop paradigms, which are patterns of thinking. These patterns of thinking often shift during the course of an experiment, so paradigms constantly shift. This is why the scientific method is usually more complex than the linear design below, but this just gives a general idea of the concept. In the diagram below, the process begins with a question. Second, the investigator will gather information and an initial understanding of their system in order to fully explore this question. Once there is enough evidence, a hypothesis will be formulated. A well-designed experiment will then be performed to produce the data required to approve or disprove the hypothesis in a defensible manner. If the data fails to disprove the hypothesis, then a new understanding of the system is produced and the process may need to start over again with a newly formed hypothesis. The method of inductive and deductive reasoning is also used through out this process. Inductive reasoning, is a type of logic in which natural laws or statements are inferred from observations. Facts are used to produce theories that explain patterns and indicate some degree of support (Wikipedia). Inductive reasoning is sometimes confused with deductive reasoning. Deductive logic is an analysis where reasoning is based on the validity and soundness of an argument. Thus, deductive reasoning draws conclusions on the basis of proofs, not merely by assuming or thinking about a predetermined clause (Buzzle.com). Both processes differ with regard to the standards of evaluation that are applicable to them. It may also be helpful to compare the Scientific Method and it's examples with that of Pseudo-Science.
#### Examples of Inductive Reasoning:
• 90% of humans are right-handed
• All swans are white
• Every life form we know of depends on water for survival
#### Examples of Deductive Reasoning:
• All men are mortal
• All apples are fruit
• All bachelors are single
### What is a Theory?
Now that you have a general idea of how the scientific method works, it is important to understand what a theory is before we move to a more developed explanation of the method. The distinction of how a hypothesis becomes a theory is not clear. It is an ambiguous distinction of when a working hypothesis has survived testing from different approaches and explains a certain phenomena. A quote from the American Association for the Advancement of Science best describes this:
A scientific theory is a well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment. Such fact-supported theories are not "guesses" but reliable accounts of the real world. The theory of biological evolution is more than "just a theory." It is as factual an explanation of the universe as the atomic theory of matter or the germ theory of disease. Our understanding of gravity is still a work in progress. But the phenomenon of gravity, like evolution, is an accepted fact.
Quite simply, a hypothesis is a prediction of what one believes may happen. This hypothesis becomes a theory when it is proven true (generally numerous times).
Also consider the Valence-Shell Electron-Pair Repulsion (VSEPR) Theory. This concept explains the geometric shape of bonded atoms and has been tested over and over again. The phenomenon of atomic bonding is indisputable, yet the VSEPR theory explains this well and has few exceptions.
### The Scientific Method Break-Down
Now, let's explore this process as defined in this model. As you can see, the scientific process is not linear, but somewhat circular. This entails you to go back and revise and retest your hypothesis and experiments. Because the Scientific Method is not a linear process, we will describe each step as a series of phases.
#### Phase A: Ask a Question
In this first important phase, use the information you have to identify a pattern and ask a question. This may be in the form of a sentence followed by a question.
Example 1) I know that this material is a solid and conducts electricity. Is it comprised of more than one element?
Example 2) I know that apples fall from trees, dust settles from the air, the earth revolves around the sun and things generally fall down. Is there a fundamental force in nature that draws two objects together in proportion to their mass?
Example 3) I know that owls live in this forest and that two species of rabbit also live in this forest. I also know that owls eat rabbits. Do the owls in this forest have a preference to the species of rabbit they eat?
Often an investigator will gather some information before extensively gathering data in order to ask a question. Questions of How, What, When, Who, Why, or Where are commonly accompanied by observations.
#### Phase B: Gather Data/ Identify a Pattern/ Conduct Research
An investigator usually can approach their study system (the chemistry lab, an ecosystem, an astronomical phenomena or a new dataset) with an initial understanding forming the core of their study, and a peripheral question at the edge of their knowledge. Thus, investigators usually have some prior knowledge of their system in the form of small amounts of data or firsthand experience. This is not always the case however. It is not uncommon for a researcher to approach a system with no prior knowledge. And in this case, the prior knowledge would come after some researching of literature, interviews or anything else in that nature. Once a familiarity has been established, this usually leads to noticing patterns or processes that may be interesting to study. Let's introduce three examples:
Example 1) A scientist has been working in a laboratory and finds a substance in a drawer in an unmarked vial. She takes the material out and examines it visually. Curious of it's composition, she determines that it is a solid and then checks to see if it conducts electricity, and it does.
Example 2) A 15th century naturalist enjoys walking in the meadow surrounding his farm. One day he sees an apple fall from the tree and begins thinking about the process that leads to objects falling down and how that might apply to the world in general.
Example 3) A college student is meandering through a forest just after sunset walking her dog. Often, in this forest, her dog will get lucky and find a rabbit to chase. Sometimes the rabbit is gray and small. Other times, the rabbit is white and large. One night, she hears an owl screech in the distance.
In these instances, curious people noticed something about their worlds and began thinking about the patterns or processes that may have lead to the phenomena they experienced. In all cases, they decided to explore their systems further. So, they asked a question and did further extensive research.
#### Phase C: Form a Hypothesis, but What Exactly is a Good One?
A good hypothesis will provide a "tentative explanation for an observation that can be tested for further investigation" (The Free Dictionary). The hypothesis should be constructed so that it can help answer the questions that you have established in the previous step (The Free Dictionary). In our examples, the investigators could now form testable hypothesis that explain the patterns in question. The hypothesis should be in the form of a statement that is easily disproved in light of the proper information.
Example 1) Hypothesis: The material in the vial is comprised of two elements, copper and zinc.
Example 2) Hypothesis: There is a fundamental force in nature that attracts two objects to each other with a force in proportion to their mass.
Example 3) Hypothesis: Owls in this forest have no preference in the species of rabbits they eat.
These hypotheses are definitive statements explaining patterns the investigators have detected. The hypothesis is testable and can be disproved with information gathered during subsequent experiments. In this case, one thing leads to another, which produces results.
#### Phase D: Conduct Experiments
The experimental phase is where one may test their information to see if the hypothesis is true or false. Experimental design is a crucial component of the Scientific Method because it determines whether the hypothesis is just a prediction or theory. Proper studies should focus on the variable in question and produce data specific to the hypothesis. Scientists often keep journals and data tables to keep track of their observations. Methods of data analysis can vary, ranging from simple plots of trends to complex statistical analysis.
Example 1) To test the hypothesis that the material is composed to two metals, she heats the substance until it turns to a gas and notes the temperatures of the phase shift. After plotting the data in a graph, she notices that the phase shift occurs at two temperatures coinciding with the phase shifts of copper and zinc.
Example 2) This investigator performs no experiments. Instead he applies the concepts of his hypothesis to mathematically explain the elliptical orbits of planets. While at it, he also develops three laws of physics which help him explain this phenomena. These mathematical formulas are successfully applied to explain many different systems ranging from objects falling from buildings to planets orbits the sun.
Example 3) The investigator examines the owl pellets at 10 known owl nests. Looking at the differences of skeleton size and fur color to determine the rabbit species consumed, she notes the number of each species at each nesting site. Plotting the data in a 10 separate graphs, she determines that some owls definitely prefer the smaller rabbits while others clearly show a preference for the larger ones.
In an experiment, there will be variables. These variables are either influenced (independent variables) or reacting (dependent variables). An independent variable will change, and a dependent variable changes as a result of change in the manipulated variable. There is also a control variable that keeps things the same. Here is an example of this:
Spongebob and his Bikini Bottom pals have been busy doing a little research. Read the description for each experiment and answer the questions.
Krusty Krabs Breath Mints
Mr. Krabs created a secret ingredient for a breath mint that he thinks will "cure" the bad breath people get from eating crabby patties at the Krusty Krab. He asked 100 customers with a history of bad breath to try his new creation. He had fifty customers (Group A) eat a breath mint after they finished eating a krabby patty. The other fifty (Group B) also received a breath mint after they finished the sandwich. (However, the mint that Group B received was just a regular breath mint that did not have the secret ingredient). Both groups were told that they were getting the breath mint that would cure their bad breath. Two hours after eating the crabby patties, thirty customers in Group A and ten customers in Group B reported having better breath than they normally had after eating crabby patties.
##### Questions:
1. Which people are the control group?
2. What is the independent variable?
3. What is the dependent variable?
4. What should Mr. Krabs' conclusion be?
5. Why do you think 10 people in Group B reported fresher breath?
1. Group B
2. Group A
3. Breath freshness
4. The secret ingredient worked
5. Placebo effect
#### Phase E: Analyze Results and Draw Conclusions / What Can be Said About the Hypothesis?
This phase is where the iterative nature of the scientific method comes from. After performing an experiment and analyzing the data, the scientist determines if the data produced disprove their hypothesis. As noted previously, it is important to understand that an experiment can never prove a hypothesis; rather it can only disprove one. If the hypothesis is disproved then the scientist can usually use the data produced from the experiment to construct a second hypothesis and then perform additional experiments building off the original hypothesis. Let's see what our three examples have done.
Example 1) Here, chemists hypothesis was that a substance was composed of two metals, copper and zinc. She performed an experiment whereby the data produced would clearly indicate if the two metals were not copper and zinc. While the data suggest (and is highly likely) that the two metals are indeed copper and zinc, and thus the substance is brass, she should perform an additional experiment.
Example 2) In this case, the scientist has performed no experiments. Rather he produced a mathematical system to explain his hypothesis and found that all things measured conform to this hypothesis. This hypothesis survived longer than the initial scientist and was later tested and applied to many other systems. In this case the hypothesis has advanced to the level of a theory. That is, it has survived many attempts to disprove it.
Example 3) Here, the investigator gathered data that showed that some owls clearly prefer small rabbits while others prefer larger rabbits. These data disproved her original hypothesis that the owls have no preference. Thus, using the data from the experiment, she could probably safely accept the hypothesis that owls have a preference for the size of rabbit they eat, and possibly take the next step to produce a new hypothesis. Two questions arise that may lead to a new hypothesis. Are there differences in the owls based on their rabbit preference (older owls eat the smaller rabbits, only male owls eat small rabbits, etc) or is there a difference in the distribution of the rabbits (only small rabbits are in the east side of the forest, etc.).
If the hypothesis is formulated appropriately, and the analyzed data are correct, the hypothesis may be considered correct and reported as a theory. If the hypothesis is not true, testing will have to be constructed again.
#### Phase F - Report Results
After all of the data are collected from an experiment and a theory is produced, results can then be communicated to the public or put into scientific research journals. It is interesting to think that any individual can develop and report the scientific method process just as a professional scientist would do.
### Conclusion:
Even though we show the scientific method as a series of steps, keep in mind that new information or thinking might cause a scientist to back up and repeat steps at any point during the process. A process like the scientific method that involves such backing up and repeating is similar to an iterative process. The scientific method is an important part of life and a grander plan that formulates a lot of theories.
### References:
1. Petrucci, Ralph. Harwood, William. Herring, Geoffrey. Madura, Jeffery. GENERAL CHEMISTRY Principles and Modern Applications 9th Edition. Macmillan Publishing co, New Jersey. 1989.
2. Campbell, Neil A. BIOLOGY Fourth Edition. The Benjamin/Cummings Publishing Company, Inc. 1996
### Concept Assessment:
1.) True or False: The Scientific Method is a linear process with a discrete start and end.
2.) True or False: An experiment can prove a hypothesis. Why?
3.) Why is it difficult to explain how a hypothesis becomes a theory?
4.) Why is the scientific method sometimes called an iterative process?
1) False. The Scientific Method is an iterative process that repeats, stops and starts in different phases depending on the application
2) False. An experiment can only falsify a hypothesis. A quote by Albert Einstein sums it up. "No amount of experimentation can ever prove me right; a single experiment can prove me wrong."
3) It is difficult to explain how a hypothesis becomes a theory because one has to understand what exactly a hypothesis and theory are. A hypothesis is simply a prediction of what someone believes will happen. A hypothesis becomes a theory when it is proven true. If the hypothesis is proven false, it stays a hypothesis.
4) The scientific method is sometimes called an iterative process because it can take different routes after experimental data are collected. If the hypothesis is disproved, a new take will be beneficial in order to get effective answers. If the hypothesis is confirmed, the results will be reported. This is constantly a cause and effect technique because there are many causes and effects that influence the whole process.
### Contributors
• Harley Brinkman (UCD)
• Tom Neils (Grand Rapids Community College)
1.1 The Terms of Science is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.
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http://toc.cs.uchicago.edu/articles/v008a020/
|
Volume 8 (2012) Article 20 pp. 429-460
Special Issue in Honor of Rajeev Motwani
Budget-Constrained Auctions with Heterogeneous Items
Published: September 4, 2012
[PDF (317K)] [PS (1455K)] [Source ZIP]
Keywords: mechanism design, approximation algorithms
ACM Classification: G.1.6, J.4
AMS Classification: 68W25
Abstract: [Plain Text Version]
We present the first approximation algorithms for designing revenue-optimal incentive-compatible mechanisms in the following setting: There are multiple (heterogeneous) items, and bidders have arbitrary demand and budget constraints (and additive valuations). Furthermore, the type of a bidder (which specifies her valuations for each item) is private knowledge, and the types of different bidders are drawn from publicly known mutually independent distributions. Our mechanisms are surprisingly simple.
First, we assume that the type of each bidder is drawn from a discrete distribution with polynomially bounded support size. This restriction on the type-distribution, however, allows the random variables corresponding to a bidder's valuations for different items to be arbitrarily correlated. In this model, we describe a sequential all-pay mechanism that is truthful in expectation and Bayesian incentive compatible. The outcome of our all-pay mechanism can be computed in polynomial time, and its revenue is a $4$-approximation to the revenue of the optimal truthful-in-expectation Bayesian incentive-compatible mechanism.
Next, we assume that the valuations of each bidder for different items are drawn from mutually independent discrete distributions satisfying the monotone hazard-rate condition. In this model, we present a sequential posted-price mechanism that is universally truthful and incentive compatible in dominant strategies. The outcome of the mechanism is computable in polynomial time, and its revenue is a $O(1)$-approximation to the revenue of the optimal truthful-in-expectation Bayesian incentive-compatible mechanism. If the monotone hazard-rate condition is removed, then we show a logarithmic approximation, and we complete the picture by proving that no sequential posted-price scheme can achieve a sub-logarithmic approximation. Finally, if the distributions are regular, and if the space of mechanisms is restricted to sequential posted-price schemes, then we show that there is a $O(1)$-approximation within this space. Our results are based on formulating novel LP relaxations for these problems, and developing generic rounding schemes from first principles.
A preliminary version of this paper appeared in STOC 2010.
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|
https://cs.stackexchange.com/questions/33127/why-arent-we-researching-more-towards-compile-time-guarantees
|
# Why aren't we researching more towards compile time guarantees?
I love all that is compile time and I love the idea that once you compile a program a lot of guarantees are made about it's execution. Generally speaking a static type system (Haskell, C++, ...) seems to give stronger compile-time guarantees than any dynamic type system.
From what I understand, Ada goes even further with regards to compile time checking, and is able to detect a greater range of bugs ahead of execution. It's also considered fairly safe, given that, at some point in time, it was chosen for delicate fields (when programming errors may cost human lives).
Now, I wonder: if stronger static guarantees, leads to code that is more documented and safe, then why aren't we researching more in that direction?
An example of something that seems to be missing, would be a language that instead of defining a generic int type that has a range determined by the number of bits of the underlying architecture, one could have ranges (in the following example Int [a..b] describes an integer type between a and b included):
a : Int [1..24]
b : Int [1..12]
a + b : Int [2..36]
a - b : Int [-11..23]
b - a : Int [-23..11]
a : Int [mod 24]
b : Int [mod 24]
a + b : Int [mod 24]
This language would select the best underlying type for the range and would perform compile time checking on the expressions. So that, for example, given:
a : Int [-3..24]
b : Int [3..10]
then:
a / b
will never be not defined.
This is just an example but I feel like there's a lot more that we can enforce at compile time. So, why there seems so little research on this? What are the technical terms that describe this idea (so that I can find more informations on this topic)? What are the limits?
• Pascal has integer subrange types (ie, 1960s), but unfortunately most implementations only check them at runtime (int(-1..4) is assignment compatible with int(100..200) at compile time). There are limited benefits from that, and contract based programming extends the idea in a better direction (Eiffel, for example). Languages like C# try to get some of those benefits with attributes, I haven't used them so not sure how useful they are in practice. – Ӎσᶎ Nov 15 '14 at 2:32
• @Ӎσᶎ: Attributes in C# are just metadata classes, so any data validation would occur at runtime. – Robert Harvey Nov 15 '14 at 3:43
• How do you know there's little research on this? Try googling dependent type or refinement type. – Phil Nov 15 '14 at 3:46
• I agree that the premise seems to be flawed; this is certainly an active research field. The work is never done. Hence, I don't quite see how this question can be answered. – Raphael Nov 15 '14 at 8:47
• @Robert Harvey: The fact that ADA provides more guarantees does not mean that the compiler will catch all errors, it will only make errors less likely. – Giorgio Nov 15 '14 at 9:16
I am not in a position to tell how much more research should be done on the topic, but I can tell you that there is research being done, for example the Verisoft XT program funded by the german government.
The concepts which I think you are looking for are called formal verification and contract based programming, where the latter is a programmer-friendly way of doing the first. In contract-based programming you first write your code as normal and then insert so called contracts into the code. A readily usable language which is based on this paradigm is Spec# by Microsoft Research, and the functionally similar but slightly less pretty Code Contracts extension for C# which you can both try out online (they also have similar tools for other languages, check out rise4fun). The "int with range type" you mentioned would by reflected by two contracts in a function:
Contract.Requires(-3 <= a && a <= 24);
Contract.Requires( 3 <= b && b <= 10);
If you want to call that function, you then have to use parameters which are ensured to meet these criteria, or you get a compile time error. The above are very simple contracts, you can insert almost any assumption or requirement about variables or exeptions and their relation which you might think of and the compiler will check if every requirement is covered by either an assumption or something that can be ensured, i.e. derived from the assumptions. That is why where the name stems from: The callee makes requirements, the caller ensures that these are met - like in a business contract.
Under the hood, code contracts are usually combined with knowledge about the inner workings (operational semantics) of the programming language into a list of verification conditions. This list represents basically one big logical proposition $P(x_1,x_2,...,x_n)$ with $n$ free variables - the inputs of your program. If the proposition $P$ is true for all possible variable assignments, then the program is considered correct. To check whether or not this is the case, an SMT Prover is used. From the CS side, those two are the critical parts of the process - the generation of verification conditions is tricky and SMT is an either NP-complete or undecidable problem, depending on the considered theories. There is even a competition for SMT solvers, so there certainly goes some research into this. Additionally, there are alternative approaches to using SMT for formal verification like state space enumeration, symbolic model checking, bounded model checking and many more which are also being researched, albeit SMT is, afaik, currently the most "modern" approach.
Regarding the limits of the general idea:
• As previously stated, proving the correctness of the program is a computationally hard problem, so it might be possible that the compile time check of a program with contracts (or another form of specification) takes really long or might be even impossible. Applying heuristics which work well most of the time is the best one can do about it.
• The more you specify about your program, the higher gets the probability of having bugs in the specification itself. This can lead to false positives (the compile time check fails even though everything is bug-free) or the false impression of being safe, even though your program still has bugs.
• Writing contracts or specifications is really tedious work and most programmers are too lazy to do it. Try writing a C# program with code contracts everywhere, after a while you will think "come on, is this really necessary?". That is why formal verification is typically just used for hardware design and safety critical systems, like software controlling airplanes or automotives.
One last thing worth mentioning which does not quite fit the above explanation is a field called "Implicit Complexity Theory", for example this paper. It aims at characterizing programing languages in which each program you can write falls into a specific complexity class, for example P. In such a language, each program you write is automatically "ensured" to be of polynomial runtime, which can be "checked" at compile time by simply compiling the program. I do not know of any practically usable results of this research, however, but I am also far from being an expert.
• Shouldn't it be possible to generate dependent types or contracts from a combination of example test(s) and untyped code, given a certain "strategy" that you can pick depending on your project? – aoeu256 Sep 8 at 14:06
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https://quant.stackexchange.com/questions/24602/calculate-total-risk
|
# Calculate total risk [closed]
I have a question regarding how the risk is calculated, if I have only the returns. I think the risk premium (rp) is just the average of the returns and the sharpe ratio is the risk premium divided by the total risk. Let me know if I am mistaken.
But how do they calculate the risk? Thanks in advance!
PS:The exercise is in the attached pictures.
## closed as off-topic by Neeraj, olaker♦Feb 29 '16 at 7:27
This question appears to be off-topic. The users who voted to close gave this specific reason:
• "Basic financial questions are off-topic as they are assumed to be common knowledge for those studying or working in the field of quantitative finance." – Neeraj, olaker
If this question can be reworded to fit the rules in the help center, please edit the question.
Notice that the problem does not give you a risk-free investment, so the computation of the Sharpe ratio becomes:
$$SR = \frac{E(r)}{\sqrt{VAR(r)}}$$
Year 1:
$r_{p} = E(r) = \frac{1}{n}\sum_{i = 1}^{n}{r_{i}} = \frac{1}{4}(-2 + 6 - 2 + 6) = \frac{1}{4}(8) = 2$
$\sigma(r_{p}) = \sqrt{VAR(r)} = \sqrt{\frac{1}{n}\sum_{i = 1}^{n}{(r_{i} - r_{p})^{2}}} = \sqrt{\frac{1}{4}((-4)^{2} + 4^{2} + (-4)^{2} + 4^{2})} = \sqrt{\frac{1}{4}(16 + 16 + 16 + 16)} = \sqrt{\frac{1}{4}(64)} = \sqrt{16} = 4$
$SR = \frac{2}{4} = 0.5$
Year 2:
$r_{p} = E(r) = \frac{1}{n}\sum_{i = 1}^{n}{r_{i}} = \frac{1}{4}(-6 + 18 - 6 + 18) = \frac{1}{4}(24) = 6$
$\sigma(r_{p}) = \sqrt{VAR(r)} = \sqrt{\frac{1}{n}\sum_{i = 1}^{n}{(r_{i} - r_{p})^{2}}} = \sqrt{\frac{1}{4}((-12)^{2} + 12^{2} + (-12)^{2} + 12^{2})} = \sqrt{\frac{1}{4}(144 + 144 + 144 + 144)} = \sqrt{\frac{1}{4}(576)} = \sqrt{144} = 12$
$SR = \frac{6}{12} = 0.5$
Year 1+2:
$r_{p} = E(r) = \frac{1}{n}\sum_{i = 1}^{n}{r_{i}} = \frac{1}{8}(-2 + 6 - 2 + 6 - 6 + 18 - 6 + 18) = \frac{1}{8}(32) = 4$
$\sigma(r_{p}) = \sqrt{VAR(r)} = \sqrt{\frac{1}{n}\sum_{i = 1}^{n}{(r_{i} - r_{p})^{2}}} = \sqrt{\frac{1}{2}((-6)^{2} + (-2)^{2} + (-6)^{2} + (-2)^{2} + (-10)^{2} + 14^{2} + (-10)^{2} + 14^{2})} = \sqrt{\frac{1}{8}(36 + 4 + 36 + 4 + 100 + 196 + 100 + 196)} = \sqrt{\frac{1}{8}(672)} = \sqrt{84} = 9.165$
$SR = \frac{4}{9.165} = 0.436$
|
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https://gmatclub.com/forum/m05-183689.html
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# M05-29
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Is $$\frac{4p}{11}$$ a positive integer?
(1) $$p$$ is a prime number
(2) $$2p$$ is divisible by 11
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Joined: 02 Sep 2009
Posts: 49438
### Show Tags
16 Sep 2014, 00:26
Official Solution:
(1) $$p$$ is a prime number. If $$p=2$$ then the answer is NO but if $$p=11$$ then the answer is YES. Not sufficient.
(2) $$2p$$ is divisible by 11. Given: $$\frac{2p}{11}=\text{integer}$$. Multiply by 2: $$2*\frac{2p}{11}=\frac{4p}{11}=2*\text{integer}=\text{integer}$$, but we don't know whether this integer is positive or not: consider $$p=0$$ and $$p=11$$. Not sufficient.
(1)+(2) Since $$p$$ is a prime number and $$2p$$ is divisible by 11, then $$p$$ must be equal to 11 (no other prime but 11 will yield integer result for $$\frac{2p}{11}$$ ), therefore $$\frac{4p}{11}=4$$. Sufficient.
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### Show Tags
02 Apr 2015, 07:46
Bunuel wrote:
Official Solution:
(1) $$p$$ is a prime number. If $$p=2$$ then the answer is NO but if $$p=11$$ then the answer is YES. Not sufficient.
(2) $$2p$$ is divisible by 11. Given: $$\frac{2p}{11}=\text{integer}$$. Multiply by 2: $$2*\frac{2p}{11}=\frac{4p}{11}=2*\text{integer}=\text{integer}$$, but we don't know whether this integer is positive or not: consider $$p=0$$ and $$p=11$$. Not sufficient.
(1)+(2) Since $$p$$ is a prime number and $$2p$$ is divisible by 11, then $$p$$ must be equal to 11 (no other prime but 11 will yield integer result for $$\frac{2p}{11}$$ ), therefore $$\frac{4p}{11}=4$$. Sufficient.
Hello,
But we still dont know if it is positive, shouldnt the answer be E?
_________________
Thanks,
aimtoteach
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### Show Tags
02 Apr 2015, 07:56
aimtoteach wrote:
Bunuel wrote:
Official Solution:
(1) $$p$$ is a prime number. If $$p=2$$ then the answer is NO but if $$p=11$$ then the answer is YES. Not sufficient.
(2) $$2p$$ is divisible by 11. Given: $$\frac{2p}{11}=\text{integer}$$. Multiply by 2: $$2*\frac{2p}{11}=\frac{4p}{11}=2*\text{integer}=\text{integer}$$, but we don't know whether this integer is positive or not: consider $$p=0$$ and $$p=11$$. Not sufficient.
(1)+(2) Since $$p$$ is a prime number and $$2p$$ is divisible by 11, then $$p$$ must be equal to 11 (no other prime but 11 will yield integer result for $$\frac{2p}{11}$$ ), therefore $$\frac{4p}{11}=4$$. Sufficient.
Hello,
But we still dont know if it is positive, shouldnt the answer be E?
Only positive numbers can be primes.
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### Show Tags
02 Apr 2015, 07:57
aimtoteach wrote:
Bunuel wrote:
Official Solution:
(1) $$p$$ is a prime number. If $$p=2$$ then the answer is NO but if $$p=11$$ then the answer is YES. Not sufficient.
(2) $$2p$$ is divisible by 11. Given: $$\frac{2p}{11}=\text{integer}$$. Multiply by 2: $$2*\frac{2p}{11}=\frac{4p}{11}=2*\text{integer}=\text{integer}$$, but we don't know whether this integer is positive or not: consider $$p=0$$ and $$p=11$$. Not sufficient.
(1)+(2) Since $$p$$ is a prime number and $$2p$$ is divisible by 11, then $$p$$ must be equal to 11 (no other prime but 11 will yield integer result for $$\frac{2p}{11}$$ ), therefore $$\frac{4p}{11}=4$$. Sufficient.
Hello,
But we still dont know if it is positive, shouldnt the answer be E?
Prime number can be only positive
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### Show Tags
22 Sep 2015, 09:24
Bunuel wrote:
Official Solution:
(1) $$p$$ is a prime number. If $$p=2$$ then the answer is NO but if $$p=11$$ then the answer is YES. Not sufficient.
(2) $$2p$$ is divisible by 11. Given: $$\frac{2p}{11}=\text{integer}$$. Multiply by 2: $$2*\frac{2p}{11}=\frac{4p}{11}=2*\text{integer}=\text{integer}$$, but we don't know whether this integer is positive or not: consider $$p=0$$ and $$p=11$$. Not sufficient.
(1)+(2) Since $$p$$ is a prime number and $$2p$$ is divisible by 11, then $$p$$ must be equal to 11 (no other prime but 11 will yield integer result for $$\frac{2p}{11}$$ ), therefore $$\frac{4p}{11}=4$$. Sufficient.
Bunuel can you please tell us all the properties of zero which will be useful in GMAT exam
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### Show Tags
22 Sep 2015, 10:40
1
2
sharma123 wrote:
Bunuel wrote:
Official Solution:
(1) $$p$$ is a prime number. If $$p=2$$ then the answer is NO but if $$p=11$$ then the answer is YES. Not sufficient.
(2) $$2p$$ is divisible by 11. Given: $$\frac{2p}{11}=\text{integer}$$. Multiply by 2: $$2*\frac{2p}{11}=\frac{4p}{11}=2*\text{integer}=\text{integer}$$, but we don't know whether this integer is positive or not: consider $$p=0$$ and $$p=11$$. Not sufficient.
(1)+(2) Since $$p$$ is a prime number and $$2p$$ is divisible by 11, then $$p$$ must be equal to 11 (no other prime but 11 will yield integer result for $$\frac{2p}{11}$$ ), therefore $$\frac{4p}{11}=4$$. Sufficient.
Bunuel can you please tell us all the properties of zero which will be useful in GMAT exam
ZERO:
1. 0 is an integer.
2. 0 is an even integer. An even number is an integer that is "evenly divisible" by 2, i.e., divisible by 2 without a remainder and as zero is evenly divisible by 2 then it must be even.
3. 0 is neither positive nor negative integer (the only one of this kind).
4. 0 is divisible by EVERY integer except 0 itself.
Check more here: number-properties-tips-and-hints-174996.html
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22 Sep 2015, 11:46
I dont understand why prime numbers are only positive. A prime is a number that has only 2 unique factors. 1 and the number itself. So why isnt -2 or -11 prime ?
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22 Sep 2015, 16:04
I got the answer correct and agree with you Bunuel. I just want to ask that in case of (2) 2p is divisible by 11, can p be a fraction like 11/7, this will still be divisible by 11.
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22 Sep 2015, 16:43
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ayushkhatri wrote:
I dont understand why prime numbers are only positive. A prime is a number that has only 2 unique factors. 1 and the number itself. So why isnt -2 or -11 prime ?
It is by definition "A prime number (or a prime) is a natural number greater than 1 that has no positive divisors other than 1 and itself. A natural number greater than 1 that is not a prime number is called a composite number." A prime is a whole number, not a fraction.
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22 Sep 2015, 22:28
knitgroove04 wrote:
I got the answer correct and agree with you Bunuel. I just want to ask that in case of (2) 2p is divisible by 11, can p be a fraction like 11/7, this will still be divisible by 11.
2p is divisible by 11 implies that 2p must be an integer. p there can be a fraction, say 11/2, but not 11/7 because in this case 2p is not an integer.
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23 Sep 2015, 09:19
Hi,
If the question just asked whether 4p/11 is an integer and not positive integer then option (B) would be correct, right?
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23 Sep 2015, 10:11
ishan92 wrote:
Hi,
If the question just asked whether 4p/11 is an integer and not positive integer then option (B) would be correct, right?
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Right.
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30 Sep 2015, 11:34
Bunuel wrote:
Is $$\frac{4p}{11}$$ a positive integer?
(1) $$p$$ is a prime number
(2) $$2p$$ is divisible by 11
1) P would have to be equal to 11. Insufficient.
2) The stem does not say that p is an integer, thus p could be 5.5, 16.5, etc., or it could also be 0 (0 is an integer though), and still follow this rule. Insufficient.
Together, p has to be a prime number that when multiplied by 2 is divisible by 11. Thus, the only possible value for p is 11.
C
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01 Oct 2015, 00:13
Question really tests properties of zero. The trick is to remember (1) the number 0 is divisible by every number except 0 (0/0 is undefined) and (2) the number 0 is not positive or negative it's neutral.
With (b) 2p is divisible by 11
Using rule (1) above, P can equal 0, 5.5, 11, 16.5, 22, etc. and the statement "2p is divisible by 11" will hold. With p=0, you have 2x0 = 0 divided by 11 = 0.
Is 4p/11 a positive integer? with p=0, 4p/11 is 0. As (2) above mentions the number 0 is not positive (or negative). so, no, it is not a positive integer. All other values of P (5.5, 11, 16.5) would yield a positive integers if plugged in 4p/11, so Yes, it is a positive integer if P is not 0. So, insufficient
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19 Jan 2016, 06:48
ayushkhatri wrote:
I dont understand why prime numbers are only positive. A prime is a number that has only 2 unique factors. 1 and the number itself. So why isnt -2 or -11 prime ?
You can look at this like,
-2 is not prime because it has more factors; ie 2, 1, -1, -2
Hence, the basic definition of prime numbers gets violated.
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09 Apr 2016, 23:58
Bunuel wrote:
Official Solution:
(1) $$p$$ is a prime number. If $$p=2$$ then the answer is NO but if $$p=11$$ then the answer is YES. Not sufficient.
(2) $$2p$$ is divisible by 11. Given: $$\frac{2p}{11}=\text{integer}$$. Multiply by 2: $$2*\frac{2p}{11}=\frac{4p}{11}=2*\text{integer}=\text{integer}$$, but we don't know whether this integer is positive or not: consider $$p=0$$ and $$p=11$$. Not sufficient.
(1)+(2) Since $$p$$ is a prime number and $$2p$$ is divisible by 11, then $$p$$ must be equal to 11 (no other prime but 11 will yield integer result for $$\frac{2p}{11}$$ ), therefore $$\frac{4p}{11}=4$$. Sufficient.
i agree with the solution. Shouldn't the final choice be - "B" only 2nd choice is correct
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10 Apr 2016, 04:30
19941010 wrote:
Bunuel wrote:
Official Solution:
(1) $$p$$ is a prime number. If $$p=2$$ then the answer is NO but if $$p=11$$ then the answer is YES. Not sufficient.
(2) $$2p$$ is divisible by 11. Given: $$\frac{2p}{11}=\text{integer}$$. Multiply by 2: $$2*\frac{2p}{11}=\frac{4p}{11}=2*\text{integer}=\text{integer}$$, but we don't know whether this integer is positive or not: consider $$p=0$$ and $$p=11$$. Not sufficient.
(1)+(2) Since $$p$$ is a prime number and $$2p$$ is divisible by 11, then $$p$$ must be equal to 11 (no other prime but 11 will yield integer result for $$\frac{2p}{11}$$ ), therefore $$\frac{4p}{11}=4$$. Sufficient.
i agree with the solution. Shouldn't the final choice be - "B" only 2nd choice is correct
The answer is NOT B because the second statement is NOT sufficient on its own. There are TWO different values of p given there giving TWO different answers to the question.
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27 Jul 2016, 13:43
Tool is great, just thought it would be nice to have the questions marked as correct once they've been answered correctly in test mode (even if previously incorrect)
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11 Aug 2016, 13:46
I don't agree with the explanation. B is stated to be sufficient and yet the answer is C
Re M05-29 &nbs [#permalink] 11 Aug 2016, 13:46
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# M05-29
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Of all publications in the section: 28
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Article
Maciel J., Bogomolov F. A. Central European Journal of Mathematics. 2009. No. 7:1. P. 61-65.
Article
Tikhomirov A. S., Markushevich D., Trautmann G. Central European Journal of Mathematics. 2012. Vol. 19. No. 4. P. 1331-1355.
We announce some results on compactifying moduli spaces of rank 2 vector bundles on surfaces by spaces of vector vector bundles on trees of surfaces. This is thought as an algebraic counterpart of the so-called bubbling of vector bundled connections an in differential geometry. The new moduli spaces are algebraic spaces arising as quotients by group actions according surfaces to a result of Kollár. As an example, the compactification of the space of stable rank 2 vector bundles with Chern classes $c_1=0, c_2=2$ on the projective plane is studied in more detail. Proofs are only indicated and will appear in separate papers.
Article
Bogomolov F. A., Tschinkel Y. Central European Journal of Mathematics. 2009. No. 7:3. P. 382-386.
Article
Bogomolov F. A., Rovinsky M. Central European Journal of Mathematics. 2013. Vol. 11. No. 1. P. 17-26.
Let Ψ be the projectivization (i.e., the set of one-dimensional vector subspaces) of a vector space of dimension ≥ 3 over a field. Let H be a closed (in the pointwise convergence topology) subgroup of the permutation group GΨ of the set Ψ. Suppose that H contains the projective group and an arbitrary self-bijection of Ψ transforming a triple of collinear points to a non-collinear triple. It is well-known from [9] that if Ψ is finite then H contains the alternating subgroup AΨ of GΨ.
We show in Theorem 3.1 below that H = GΨ, if Ψ is infinite.
Article
Markushevich D., Tikhomirov A. S., Verbitsky M. Central European Journal of Mathematics. 2012. Vol. 10. No. 4. P. 1185-1187.
Article
Tikhomirov A. S., Markushevich D., Verbitsky M. Central European Journal of Mathematics. 2012. Vol. 10. No. 4. P. 1185-1187.
In this preface we give a short description of the current issue of the Central European Journal of Mathematics containing 22 papers which spin around the topics of the conference “Instantons in complex geometry”, held on March 14–18, 2011 in Moscow. The main goal of the conference was to bring together specialists in complex algebraic and analytic geometries whose research interests belong to this composite area between gauge theory, moduli spaces, derived categories, vector bundles and coherent sheaves. Besides the most relevant contributions to the conference, the issue contains miscellaneous articles by other authors that fit by subject and spirit.
Article
Katzarkov L., Yotov M., Orlov D. O. et al. Central European Journal of Mathematics. 2009. No. 7:4.
Article
Przyjalkowski V. V. Central European Journal of Mathematics. 2011. Vol. 9. No. 5. P. 972-977.
Article
Verbitsky M. Central European Journal of Mathematics. 2011. Vol. 9. No. 3. P. 535-557.
Article
Kuznetsov A. G. Central European Journal of Mathematics. 2012. Vol. 10. No. 4. P. 1198-1231.
We introduce the notion of an instanton bundle on a Fano threefold of index 2. For such bundles we give an analogue of a monadic description and discuss the curve of jumping lines. The cases of threefolds of degree 5 and 4 are considered in a greater detail.
Article
Bogomolov F. A., Böhning C., Graf von Bothmer H. Central European Journal of Mathematics. 2012. Vol. 10. No. 2. P. 466-520.
Let G be one of the groups SL n(ℂ), Sp 2n(ℂ), SO m(ℂ), O m(ℂ), or G 2. For a generically free G-representation V, we say that N is a level of stable rationality for V/G if V/G × ℙ N is rational. In this paper we improve known bounds for the levels of stable rationality for the quotients V/G. In particular, their growth as functions of the rank of the group is linear for G being one of the classical groups.
Article
Tikhomirov A. S., Bruzzo U., Markushevich D. Central European Journal of Mathematics. 2012. Vol. 10. No. 4. P. 1232-1245.
Symplectic instanton vector bundles on the projective space $\mathbb{P}^3$ constitute a natural generalization of mathematical instantons of rank-2. We study the moduli space $I_{n;r}$ of rank-$2r$ symplectic instanton vector bundles on $\mathbb{P}^3$ with $r\ge2$ and second Chern class $n\ge r, n\equiv r(\mod 2)$. We introduce the notion of tame symplectic instantons by excluding a kind of pathological monads and show that the locus $I_{n;r}^*$ of tame symplectic instantons is irreducible and has the expected dimension, equal to $4n(r+1)-r(2r+1)$.
Article
Tschinkel Y., Bogomolov F. A. Central European Journal of Mathematics. 2008. No. 6:3. P. 343-350.
Article
Drozd Y., Gavran V. Central European Journal of Mathematics. 2014. Vol. 12. No. 5. P. 675-687.
We generalize the results of Kahn about a correspondence between Cohen-Macaulay modules and vector bundles to non-commutative surface singularities. As an application, we give examples of non-commutative surface singularities which are not Cohen-Macaulay finite, but are Cohen-Macaulay tame.
Article
Arzhantsev I., Bazhov I. Central European Journal of Mathematics. 2013. Vol. 11. No. 10. P. 1713-1724.
Let X be an affine toric variety. The total coordinates on X provide a canonical presentation !X -> X of X as a quotient of a vector space !X by a linear action of a quasitorus. We prove that the orbits of the connected component of the automorphism group Aut(X) on X coincide with the Luna strata defined by the canonical quotient presentation.
Article
Bogomolov F. A., Prokhorov Y. Central European Journal of Mathematics. 2013. Vol. 11. No. 12. P. 2099-2105.
We discuss the problem of stable conjugacy of finite subgroups of Cremona groups. We show that the group $H^1(G,Pic(X))$ is a stable birational invariant and compute this group in some cases.
Article
Bogomolov F. A., Kulikov V. S. Central European Journal of Mathematics. 2012. Vol. 10. No. 2. P. 521-529.
We show that the diffeomorphic type of the complement to a line arrangement in a complex projective plane P 2 depends only on the graph of line intersections if no line in the arrangement contains more than two points in which at least two lines intersect. This result also holds for some special arrangements which do not satisfy this property. However it is not true in general, see [Rybnikov G., On the fundamental group of the complement of a complex hyperplane arrangement, Funct.
Article
Bogomolov F. A., Kulikov V. S. Central European Journal of Mathematics. 2013. Vol. 11. No. 2. P. 254-263.
The article contains a new proof that the Hilbert scheme of irreducible surfaces of degree m in ℙ m+1 is irreducible except m = 4. In the case m = 4 the Hilbert scheme consists of two irreducible components explicitly described in the article. The main idea of our approach is to use the proof of Chisini conjecture [Kulikov Vik. S., On Chisini's conjecture II, Izv. Math., 2008, 72(5), 901-913 (in Russian)] for coverings of projective plane branched in a special class of rational curves.
Article
Bogomolov F. A., Zarhin Y. Central European Journal of Mathematics. 2009. No. 7:2. P. 206-213.
Let $\bbk$ be a field of characteristic zero and $G$ be a finite group of automorphisms of projective plane over $\bbk$. Castelnuovo's criterion implies that the quotient of projective plane by $G$ is rational if the field $\bbk$ is algebraically closed. In this paper we prove that $\mathbb{P}^2_{\bbk} / G$ is rational for an arbitrary field $\bbk$ of characteristic zero.
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http://www.dummies.com/how-to/content/string-theory-testing-supersymmetry.navId-811234.html
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One major prediction of string theory is that a fundamental symmetry exists between bosons and fermions, called supersymmetry. For each boson there exists a related fermion, and for each fermion there exists a related boson. (Bosons and fermions are types of particles with different spins.)
## Finding the missing sparticles
Under supersymmetry, each particle has a superpartner. Every boson has a corresponding fermionic superpartner, just as every fermion has a bosonic superpartner. The naming convention is that fermionic superpartners end in “–ino,” while bosonic superpartners start with an “s.” Finding these superpartners is a major goal of modern high-energy physics.
The problem is that without a complete version of string theory, string theorists don’t know what energy levels to look at. Scientists will have to keep exploring until they find superpartners and then work backward to construct a theory that contains the superpartners. This seems only slightly better than the Standard Model of particle physics, where the properties of all 18 fundamental particles have to be entered by hand.
Also, there doesn’t appear to be any fundamental theoretical reason why scientists haven’t found superpartners yet. If supersymmetry does unify the forces of physics and solve the hierarchy problem, then scientists would expect to find low-energy superpartners. (The search for the Higgs boson has undergone these same issues within the Standard Model framework for years. It has yet to be detected experimentally either.)
Instead, scientists have explored energy ranges into a few hundred GeV, but still haven’t found any superpartners. So the lightest superpartner would appear to be heavier than the 17 observed fundamental particles. Some theoretical models predict that the superpartners could be 1,000 times heavier than protons, so their absence is understandable (heavier particles often tend to be more unstable and collapse into lower-energy particles if possible) but still frustrating.
Right now, the best candidate for a way to find supersymmetric particles outside of a high-energy particle accelerator is the idea that the dark matter in our universe may actually be the missing superpartners.
## Testing implications of supersymmetry
If supersymmetry exists, then some physical process takes place that causes the symmetry to become spontaneously broken as the universe goes from a dense high-energy state into its current low-energy state.
In other words, as the universe cooled down, the superpartners had to somehow decay into the particles we observe today. If theorists can model this spontaneous symmetry-breaking process in a way that works, it may yield some testable predictions.
The main problem is something called the flavor problem. In the standard model, there are three flavors (or generations) of particles. Electrons, muons, and taus are three different flavors of leptons.
In the Standard Model, these particles don’t directly interact with each other. (They can exchange a gauge boson, so there’s an indirect interaction.) Physicists assign each particle numbers based on its flavor, and these numbers are a conserved quantity in quantum physics.
The electron number, muon number, and tau numbers don’t change, in total, during an interaction. An electron, for example, gets a positive electron number but gets 0 for both muon and tau numbers.
Because of this, a muon (which has a positive muon number but an electron number of zero) can never decay into an electron (with a positive electron number but a muon number of zero), or vice versa. In the Standard Model and in supersymmetry, these numbers are conserved, and interactions between the different flavors of particles are prohibited.
However, our universe doesn’t have supersymmetry — it has broken supersymmetry. There is no guarantee that the broken supersymmetry will conserve the muon and electron number, and creating a theory of spontaneous supersymmetry breaking that keeps this conservation intact is actually very hard. Succeeding at it may provide a testable hypothesis, allowing for experimental support of string theory.
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http://clay6.com/qa/10442/solve-ii-x-4-x-3-x-2-x-1-0
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Browse Questions
# Solve : $x^4-x^3+x^2-x+1=0$
This is the second part of the multi-part question Q4
Toolbox:
• From De moivre's theorem we have
• (i) $(\cos\theta+i\sin\theta)^n=\cos n\theta+i\sin n\theta,n\in Q$
• (ii) $(\cos\theta+i\sin\theta)^{-n}=\cos n\theta-i\sin n\theta$
• (iii) $(\cos\theta-i\sin\theta)^n=\cos n\theta-i\sin n\theta$
• (iv) $(\sin \theta+i\cos \theta)^n=[\cos(\large\frac{\pi}{2}$$-\theta)+i\sin(\large\frac{\pi}{2}$$-\theta)]^n=\cos n(\large\frac{\pi}{2}$$-\theta)+i\sin n(\large\frac{\pi}{2}$$-\theta)$
• $e^{i\theta}=\cos\theta+i\sin\theta$
• $e^{-i\theta}=\cos\theta-i\sin\theta$,also written as $\cos\theta$ and $\cos(-\theta)$
Step 1:
$x^4-x^3+x^2-x+1=0$--------(1)
Multiplying by $4(x+1)$ we have the equation
$(x+1)(x^4-x^3+x^2-x+1)=0$
$x^5+1=0$---------(2)
The roots of equ(1) are the same as those of equ(2) except for $x=-1$
Step 2:
Solving eq(2) we have $x=(-1)^{\large\frac{1}{5}}$
$x=(\cos\pi+i\sin\pi)^{\large\frac{1}{5}}$
$\;\;=(\cos2k\pi+\pi)+i\sin(2k\pi+\pi))^{\large\frac{1}{5}}\;\;\;k\in z$
$\;\;=[\cos(2k+1)\pi+i\sin(2k+1)\pi)]^{\large\frac{1}{5}}\;\;\;k\in z$
$\;\;=[\cos(2k+1)\large\frac{\pi}{5}$$+i\sin(2k+1)\frac{\pi}{5}]^{\large\frac{1}{5}}\;\;\;k=0,1,2,3,4 Step 3: Th value k=2 gives x=\cos\pi+i\sin\pi=-1 Which is not a root of eq(1). The roots of eq(1) are cis\large\frac{\pi}{5},$$cis\large\frac{3\pi}{5},$$cis\large\frac{7\pi}{5},$$cis\large\frac{9\pi}{5}$
$\Rightarrow cis\large\frac{\pi}{5},$$cis\large\frac{3\pi}{5},$$cis(\large\frac{7\pi}{5}-$$2\pi),$$cis(\large\frac{9\pi}{5}$$-2\pi) \Rightarrow cis\big(\pm\large\frac{ \pi}{5}\big),$$cis\big(\pm\large\frac{ 3\pi}{5}\big)$
edited Sep 12, 2013
cis(±±π/5) should be changed to cis(±π/5)
Thanks for pointing it out, its fixed now.
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https://encyclopedia.pub/entry/35855
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Applications of g-C3N4-Based Photocatalysts
The assembly of g-C3N4 with metal oxides is an effective strategy which can not only improve electron–hole separation efficiency by forming a polymer–inorganic heterojunction, but also compensate for the redox capabilities of g-C3N4 owing to the varied oxidation states of metal ions, enhancing its photocatalytic performance. Applications of g-C3N4-based materials in photocatalysis are discussed, including water splitting to generate H2 and O2, the degradation of pollutants, CO2 reduction and bacterial disinfection.
g-C3N4 water synthesis
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1. Photocatalytic Water Splitting for H2
Because of the decreasing storage of fossil fuels and their negative impacts on the environment (releasing CO2 for example), the use of green and renewable hydrogen fuels attracts much attention from scientists. The photocatalytic splitting of water is an ideal way to generate hydrogen and has become a hot topic in recent years. Figure 1 presents a simplified diagram of splitting water into hydrogen and oxygen over g-C3N4 under light irradiation. First, g-C3N4 is excited by photons to generate electrons, which then jump to the CB, leaving holes at the VB. The photogenerated e and h+ flow to the surface of g-C3N4, reducing and oxidizing the adsorbed water to hydrogen and oxygen, respectively. However, the generated e/h+ will rapidly recombine each other due to the Coulombic attraction, losing activity. The improvement in the separation efficiency of the photogenerated e/h+ pairs, thus, is a challenging topic in the field of g-C3N4 photocatalysis.
Figure 1. Scheme of photocatalytic water splitting into H2 and O2 over g-C3N4 under light irradiation.
To achieve this, the coupling of g-C3N4 with metal oxide is a solution, which can separate e/h+ pairs in space by forming an opposite flow of e and h+ (for type II heterojunctions), or by inducing the recombination of unused e and h+ (for Z-Scheme heterojunctions), as reported in the literature [1][2]. Shi et al. [3] reported the in situ synthesis of MoO3/g-C3N4, via co-pyrolysis of MoS2 and melamine, for photocatalytic water splitting to hydrogen, finding that the activity of g-C3N4 was significantly enhanced with the increase in MoO3 content. It is possible that the use of layered MoS2 as a precursor not only improves the dispersion of MoO3 on g-C3N4, but also enhances the interactions between them. Li et al. [4] synthesized W18O49/g-C3N4 composites by roasting a g-C3N4-impregnated ammonium tungstate solution. The loading of W18O49 greatly improves the surface area (by about five times) and exhibits excellent activity for a photocatalytic hydrogen evolution reaction, with a reaction rate of 912.3 μmol⋅g−1⋅h−1, which is 9.7 times higher than that of g-C3N4.
The coupling of g-C3N4 with two metal oxides could be more interesting when compared to that with single-metal oxide, as multiple heterojunctions can be established, exhibiting rich optical properties, and hence, better photocatalytic activities. This is observed in many studies [5][6][7]. For example, Wang et al. [8] found that Fe2O3@MnO2 core-shell g-C3N4 ternary composites can form double heterojunctions, which provide abundant channels for electrons transfer, exhibit enhanced optical properties and allow the two half-reactions (the production of hydrogen and oxygen) to occur on the opposite surfaces of the semiconductor ; this results in improved activity for both hydrogen and oxygen production, with an optimal reaction rate of 124 μmol⋅h−1 and 60 μmol⋅h−1, respectively.
2. Photocatalytic Reduction of CO2 to Renewable Hydrocarbon Fuels
With increasing global warming, it is critical to find effective ways to deal with greenhouse gases. Carbon dioxide (CO2) is not only a typical greenhouse gas but also a valuable C1 resource. Hence, utilizing solar energy to reduce CO2 into higher-value chemicals shows great advantages in solving the problems of both global warming and energy crises. In the past few years, g-C3N4 has been employed as a photocatalyst for CO2 reduction owing to its high CB potential, which can activate CO2 by donating electrons to the unoccupied orbits of CO2. The photocatalytic CO2 reduction involves a proton-assisted multi-electron process, as shown in Equations (1)–(5) below [9]. From the viewpoint of thermodynamics, CO2 is gradually reduced to HCOOH, CO, HCHO, CH3OH and CH4 by receiving multiple (2, 2, 4, 6 and 8) electrons and protons, accompanying the increase in reduction potential. This means that the photocatalyst used to reduce CO2 should have strong redox capability in order to supply sufficient driving force for the reaction.
$\begin{array}{r}{\mathrm{CO}}_{2}+{\mathrm{2H}}^{+}+{\mathrm{2e}}^{-}\to \mathrm{HCOOH}\\ {{E}^{0}}_{\mathrm{redox}}=-\mathrm{0.6V \left(vs. NHE at pH 7\right)}\end{array}$
$\begin{array}{r}{\mathrm{CO}}_{2}+{\mathrm{2H}}^{+}+{\mathrm{2e}}^{-}\to \mathrm{CO}+{H}_{2}O\\ {{E}^{0}}_{\mathrm{redox}}=-\mathrm{0.53V \left(vs. NHE at pH 7\right)}\end{array}$
$\begin{array}{r}{\mathrm{CO}}_{2}+{\mathrm{4H}}^{+}+{\mathrm{4e}}^{-}\to \mathrm{HCHO}+{H}_{2}O\\ {{E}^{0}}_{\mathrm{redox}}=-\mathrm{0.48V \left(vs. NHE at pH 7\right)}\end{array}$
$\begin{array}{r}{\mathrm{CO}}_{2}+{\mathrm{6H}}^{+}+{\mathrm{6e}}^{-}\to {\mathrm{CH}}_{3}\mathrm{OH}+{H}_{2}O\\ {{E}^{0}}_{\mathrm{redox}}=-\mathrm{0.38V \left(vs. NHE at pH 7\right)}\end{array}$
$\begin{array}{r}{\mathrm{CO}}_{2}+{\mathrm{8H}}^{+}+{\mathrm{8e}}^{-}\to {\mathrm{CH}}_{4}+{}_{2}{H}_{2}O\\ {{E}^{0}}_{\mathrm{redox}}=-\mathrm{0.24V \left(vs. NHE at pH 7\right)}\end{array}$
ZnO can absorb CO2 and has a CB potential (ECB) of −0.44 eV, which is more negative than the reduction potential of CO2. Therefore, the combination of ZnO and g-C3N4 would benefit the CO2 reduction reaction. Indeed, it is found that although the deposition of ZnO has negligible effects on the light absorption capacity and surface area of g-C3N4, the ZnO/g-C3N4 composite shows better photocatalytic activity for CO2 reduction than individual ZnO and g-C3N4, due to the formation of heterojunctions that facilitate the separation of e/h+ pairs [10]. The CO2 conversion rate obtained from ZnO/g-C3N4 reaches 45.6 μmol/g/h, which is 4.9 times and 6.4 times higher than that obtained from g-C3N4 and P25, respectively. Additionally, based on the fact that the zeta potential of ZnO is positive and that of g-C3N4 is negative, Nie et al. [11] constructed a ZnO/g-C3N4 composite using an electrostatic self-assembly method. The combination of them induces synergistic effects that are conducive to photocatalytic reactions, in which the ZnO microsphere prevents falling g-C3N4 nano flakes from gathering, and the g-C3N4 improves light utilization efficiency through the multi-scattering effect.
In addition to ZnO, many other metal oxides can couple with g-C3N4 and contribute to the CO2 reduction reaction. For example, Bhosale et al. [12] employed a wet chemical method to couple FeWO4 with g-C3N4, forming a Z-scheme g-C3N4/FeWO4 photocatalyst; it showed good activity for the reduction of CO2 to CO without any medium, with a CO production rate of 6 µmol/g/h, which is 6 and 15 times higher than that of individual g-C3N4 and FeWO4.
With the rapid development of the economy, various toxic pollutants emitted from industrial plants have been discharged to the environment and have seriously destroyed the ecological system. The removal of pollutants and the remediation of the environment have thus become essential topics and have attracted broad attention in recent years. Photocatalysis is a prospective technology for pollutant removal, and is able to mineralize organic pollutants into CO2 and H2O by producing oxidizing intermediates (such as •O2, •OH and h+). Depending on the properties of the pollutants, three reaction types can be classified: (1) the removal of organic pollutants in aqueous solution, such as dye [4][13] and antibiotic degradation [14]; (2) the removal of heavy-metal cations in aqueous solution, such as the reduction of chromium (VI) [15]; and (3) the removal of organic or inorganic pollutants in gas phase, such as the degradation of ortho-dichlorobenzene [16], acetaldehyde [17] and nitric oxide [18].
The Fenton advanced oxidation process (with an Fe2+ and H2O2 system) is a traditional technology used to treat industrial wastewater, but it is limited to a narrow pH range (<3) and causes secondary pollution due to the production of iron sludge. For this reason, it is proposed that a photocatalyst should be used instead of Fe2+, to activate H2O2 into •OH radicals under light irradiation conditions, which can be achieved in a wide pH range without producing secondary pollutants. Hence, it is a green route to removing organic pollutants in aqueous solution and has good prospects for industrial use.
In this respect, Xu et al. [19] recently reported that the LFO@CN photocatalyst is highly efficient for the oxidative degradation of RhB with H2O2 under visible-light irradiation, with 98% conversion obtained within 25 min, and the material can be recycled for four cycles with no appreciable deactivation. Moreover, when applying a ternary LaFe0.5Co0.5O3/Ag/g-C3N4 heterojunction that consists of a redox part LaFe0.5Co0.5O3 (LFCO), photo part g-C3N4 and plasmonic part (Ag), for the degradation of tetracycline hydrochloride (TC), in the presence of H2O2 and light irradiation, the system exhibits good activity due to a photo-Fenton effect induced in the reaction. In this system, H2O2 is first activated into •OH radicals and OH anions over the LFCO, and the OH anions subsequently react with holes (h+) produced at the VB band of LFCO to form more •OH radicals. Hence, H2O2 can be fully utilized to oxidize TC in the reaction. Meanwhile, the O2 dissolved in the solution can react with the electrons (e) generated at the CB band of g-C3N4 and form •O2, which is also a strong oxidant that is able to oxidize TC into CO2 and H2O. These results support that g-C3N4-based catalysts have good chemical stability and can be an effective substitute for Fenton catalysts in environmental purification.
In addition to the direct addition of H2O2, the photocatalytic in situ generation of H2O2 in the reaction for pollutant oxidation, which is a more promising way but a more challenging topic, is also possible. For example, Xu et al. reported that ternary g-C3N4/Co3O4/Ag2O heterojunctions can accelerate the mineralization of RhB due to the presence of H2O2 in situ, produced from O2 reduction [20]. Through studying the catalytic behavior of the composites in the electrochemical oxygen reduction reaction (ORR), they found that the average number of electrons transferred in the reaction is 2.07, which indicates that the two-electron O2 reduction process is the dominant step in the reaction.
The morphology of metal oxide, the interface interaction between metal oxide and g-C3N4 and the method of coupling metal oxide with g-C3N4 are also crucial factors affecting the photocatalytic performance of g-C3N4 for pollutant removal. For instance, the coupling of cubic CeO2 (3~10 nm) with g-C3N4 using a hydrothermal method can greatly improve the activity of g-C3N4 for methyl orange degradation, with the reaction rate reaching 1.27 min−1, which is 7.8 times higher than that of g-C3N4 alone (0.16 min−1) [21]. The hybridization of NiO with g-C3N4 causes a red shift in the UV absorption edge and boosts the ability of light response; hence, it exhibits improved activity for methylene blue degradation, which is about 2.3 times higher than that of g-C3N4 [22]. Similar phenomena are also observed for other materials, e.g., TiO2-In2O3@g-C3N4 [23].
The heavy-metal ions produced in electroplating, metallurgy, printing and dyeing, medicine and other industries cause serious damage to the ecological environment. Cr(VI) is a typical heavy metal in wastewater and its removal receives wide attention. The photocatalytic reduction of Cr(VI) to Cr(III) is an efficient way to treat Cr(VI)-containing wastewater, due to its simple process, energy savings, high efficiency and lower levels of secondary pollution [24]. It has been reported that the in situ self-assembly of g-C3N4/WO3 in different organic acid media can lead to various surface morphologies and catalytic activities for Cr(VI) removal, as the number of carboxyl groups in organic acid greatly affects the shape and performance of g-C3N4/WO3. Its synthesis in ethanedioic acid medium, which contains two carboxyl groups, yields a disc shape and has the best activity for nitroaromatic reduction. Furthermore, the material has good stability for the reaction, with no appreciable activity loss within four cycles.
Bi2WO6 is a promising semiconductor that can couple with g-C3N4 and form a heterojunction for the photocatalytic treatment of Cr(VI)-containing wastewater. Song et al. [25] found that a C3N4/Bi2WO6 composite prepared using a hydrothermal method exhibits a surface area up to 46.3 m2/g and shows a rate constant of 0.0414 min−1 for the photocatalytic reduction of Cr(VI), as the high surface area of the catalyst facilitates not only the reactant’s adsorption, but also the visible-light absorption.
Photocatalysis is also effective for removing gas-phase pollutants and receives great interest from scientists. It is known that air pollution is a big problem for the environment, and causes serious harm to the human body and ecological systems by forming acid rain, chemical smog, particulate matter, etc. Hence, seeking an effective and feasible technology for its removal is a challenging topic. Photocatalysis provides a way to remove air pollutants (e.g., NOx) by installing catalysts either inside the exhaust pipe or on the road surface [26]. As a typical photocatalyst, g-C3N4-based materials are also widely investigated in this aspect. Zhu et al. reported that g-C3N4 is active in NO removal via thermal catalysis, and proposed that the N atoms of g-C3N4, with a lone electron pair, serve as the active site of NO by donating electrons to weaken the N-O bond order [27]. This lays the foundation or using photocatalysis for NO removal, as electrons can be effectively excited from g-C3N4 under light irradiation.
However, it is known that the surface area of g-C3N4 prepared using the thermal condensation method is small, which grfieatly limits the light absorption capacity, the e/h+ separation efficiency and other physicochemical properties; thus, many strategies have been adopted to overcome this problem. For example, Sano et al. [28] reported that pretreating melamine with NaOH solution before the condensation process favors the hydrolysis of unstable domains and the generation of mesopores in the structure of g-C3N4, leading to an increase in surface area from 7.7 m2/g to 65 m2/g, and the NO oxidation activity is accordingly increased 8.6 times. Duan et al. [18] found that flower-like g-C3N4 prepared using the self-assembly method can notably improve photocatalytic activity for NO oxidation compared to bulk g-C3N4, owing to the enlargement of the BET surface area, the formation of nitrogen vacancies, the condensation of π–π layer stacking, and the improvement in e/h+ separation efficiency. The alternation of the precursor, e.g., urea [29] and guanidine hydrochloride [30] is also efficient in preparing g-C3N4 with a large surface area and improving photocatalytic performance.
4. Sterilization and Disinfection
In addition to the above applications, photocatalysis is also widely applied to inactivate pathogens in surface water owing to its broad compatibility, long durability, anti-drug resistance and thorough sterilization [31]. Bacteria, such as salmonella, staphylococcus aureus and bacillus anthracis, are commonly used as model pathogens to evaluate photocatalytic disinfection efficiency. Since the first work of Matsunaga et al. [32] on photochemical sterilization in 1985, this technique has rapidly developed and receives great interest from scientists. The principle of photocatalytic sterilization is to excite and separate the e/h+ pairs via illumination; the photoinduced electrons and/or holes then inactivate the bacteria by directly or indirectly inflicting oxidative damage on their organs (through the formation of •O2, •OH, etc.). Hence, the disinfection efficiency of materials closely depends on the properties that influence the generation and separation of e/h+ pairs, e.g., the surface area, the band gap and the surface morphology, as reported for other photocatalytic processes.
In the case of g-C3N4, Huang et al. [33] found that mesoporous g-C3N4 synthesized using the hard template method can inactivate most of the bacteria (e.g., E. coli K-12) within 4 h, owing to its large surface area, which allows more active sites exposed on the surface to produce h+ for bacterial disinfection. To support that the inactivation of bacteria is caused by photocatalysis, Xu et al. [34] conducted a dark contrasting experiment using a porous g-C3N4 nanosheet (PCNS) as the photocatalyst and E. coli as the model bacteria; they found that the adsorption of E. coli on PCNS reaches equilibrium within 1 h and about 85.5% of E. coli survive after 4 h, while nearly 100% of E. coli are killed by PCNS within 4 h under visible-light irradiation. This demonstrates that the PCNS has little toxic effect on E. coli and the disinfection is mainly caused by the electrons or holes induced from PCNS under light irradiation.
In addition to bacterial infection, viral outbreaks, including SARS, bird flu, Ebola and the recent COVID-19, are also important events related to human health, and they are generally more resistant than bacteria to conventional disinfection due to their small size. Thus, the inactivation of viruses normally requires strong oxidative agents. g-C3N4-based materials have good photocatalytic reactivity to produce strong oxidative agents, e.g., •O2 and •OH; hence, they are potential photocatalysts for virus inactivation. It has been reported that phage MS2 can be completely inactivated by g-C3N4 under visible-light irradiation within 360 min [35], and the main active species for the reaction are •O2 and •OH. The loss of protein triggers the leakage and rapid destruction of internal components, and ultimately leads to the death of the virus without regrowth.
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https://www.physicsforums.com/threads/forces-problem.185077/
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# Forces Problem
1. Sep 16, 2007
### bob1182006
I have 2 problems I just can't seem to get so I'll post both here instead of making 2 threads.
Both of these are from Halliday & Resnick 5th ed chapter 3 Problems.
Problem #1.
1. The problem statement, all variables and given/known data
A light beam from a satellite-carried laser strikes an object ejected from an accidentally launched ballistic missile. The beam exerts a force of $2.0 * 10^{-5}$ N on the target.
If the "dwell time" of the beam on the target is 2.4s by how much is the object displaced if it is
b) a 2.1-kg decoy?
(These displacements can be measured by observing the reflected beam)
2. Relevant equations
$$\triangle x=v_0 t +\frac{1}{2}at^2$$
F=ma
3. The attempt at a solution
The missile experiences some uknown horizontal acceleration/velocity so I will just ignore those..
It also experiences a downward acceleration of g.
So does the laser beam?
I need to find the sum of the forces to find the acceleration.
$$\frac{mg+2.7*10^{-5}}{m}$$ for a I get about 9.8 m/s^2 .
Plugging that into the equation I get a displacement of about 56m but the answer should be some micro-meters..
Problem #9.
1. The problem statement, all variables and given/known data
A chain consisting of five links, each with mass 100g, is lifted vertically with a constant a =2.5m/s^2.
Find
b) the force F exerted on the top link by the agent lifting the chain
c) the net force on each link
2. Relevant equations
F=ma
3. The attempt at a solution
2.5m/s^2 up
-9.8m/s^2 up
a total of -7.3m/s^2 up
for a.
add up the masses of link+links beneath it and then multiply by 7.3m/s^2 to get a force of:
.5kg*7.3m/s^2 = 3.65 N being exerted on the top link.
Which is completely wrong :/.
for b.
find the total mass and multiply by 7.3m/s^2
F=.5kg*7.3m/s^2=3.65 N
again completely wrong..
for c.
Somehow I got this right...
lowest link force acting upon it is: .1kg*2.5m/s^2 = .25 N
...for all others
then subtracting the link force - link below it to get a net force of .25 N on each link.
Any help on either problem is greatly appreciated.
2. Sep 16, 2007
### bob1182006
I'm mainly trying to get problem #9.
I was working backwards from the answers the book gave.
for a the lowest # and thus the lowest link in the chain I think.
has a total force of 1.23N which requires a force of 12.3 m/s^2 (g+2.5) on a mass of 100g.
Isn't this wrong though? since there's a downward force of .1g N but an upward of .1*2.5 N but somehow the in the book they're adding them...
3. Sep 16, 2007
### learningphysics
For the first problem, I don't think you should use mg... we don't really know anything about the missile... it may not be accelerating downwards at g (it may have its own thrust or something). we also don't know that the laser is directed straight upwards...
4. Sep 16, 2007
### learningphysics
For problem 9, part b)
Write this equation out:
$$\Sigma\vec{F} = ma$$
5. Sep 16, 2007
### PhanthomJay
I don't think you are corrrectly applying newton 2 in your free body diagrams. Isolating the bottom link, there are 2 forces acting on it. You have correctly identified the downward force. The upward force is unknown...call it T. Now use newton 2nd law....F_net = ma. a is given, don't mess with it.
6. Sep 16, 2007
### bob1182006
Yea the first problem is wierd especially the "These displacements can be measured by observing the reflected beam" o.o since it's barely chapter 3 and I have no knowledge of optics so far.
So sticking to #9.
for part a, there are 2 forces acting on each link, 1 up and 1 down, I add them together right?
.1 kg * 2.5 m/s^2=.25 N
.1 kg * 9.8 m/s^2=.98 N
total being 1.23 N
1.23 N + (.1kg * 2.5 m/s^2 + .2kg * 9.8 m/s^2) = 1.23 N + 1.23 N=2.46
and so forth for the rest correct?
for part b)
I would do almost the same as I did for part a correct? part a I stop adding @ the 4th link since it has force exerted by the 5th which is topmost and the 3rd beneath it.
7. Sep 16, 2007
### learningphysics
Not sure what happened above... : .1kg * 2.5 m/s^2 + .2kg * 9.8 m/s^2 is not 1.23... but 2.46 is the correct answer though.
8. Sep 16, 2007
### bob1182006
sorry did it first as 2ma+2mg=2.46 N
but split it up into (ma+mg)+(ma+mg)=2.46N
just forgot to change that .2 to a .1.
But I'm still curious, why is it that when I add ma and mg they are both positive? a is pointing up but g is pointing down so shouldn't they be subtracting?....
9. Sep 16, 2007
### learningphysics
If you're lifting 1 kg object upwards at an acceleration 1.0m/s^2 in a gravityless environment... you only need to exert 1N of force.
If you're lifting 1 kg object upwards at an acceleration 1.0m/s^2 in a 9.8m/s^2 gravity environment... you'll need to exert a greater force... you're exerting a force to compensate for gravity.
Fnet = ma
Fupwards - mg = ma
Fupwards = ma + mg
The greater the gravity... the greater the force required to compensate for gravity, and move the object at the same acceleration.
10. Sep 16, 2007
### bob1182006
ok I think I get it now.
so when I find ma for .1kg m the net force IS .1*2.5=.25N but that is the total of the force I want - mg so that's why I add the mg!
Thanks alot!!
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http://www.researchgate.net/publication/51935189_Phase_Diagram_for_Magnetic_Reconnection_in_Heliophysical_Astrophysicaland_Laboratory_Plasmas
|
Article
# Phase Diagram for Magnetic Reconnection in Heliophysical, Astrophysical and Laboratory Plasmas
(Impact Factor: 2.25). 09/2011; 18(11). DOI: 10.1063/1.3647505
Source: arXiv
ABSTRACT Recent progress in understanding the physics of magnetic reconnection is
conveniently summarized in terms of a phase diagram which organizes the
essential dynamics for a wide variety of applications in heliophysics,
laboratory and astrophysics. The two key dimensionless parameters are the
Lundquist number and the macrosopic system size in units of the ion sound
collisionless phases, multiple X-line reconnection phases arise due to the
presence of the plasmoid instability either in collisional and collisionless
current sheets. In particular, there exists a unique phase termed "multiple
X-line hybrid phase" where a hierarchy of collisional islands or plasmoids is
terminated by a collisionless current sheet, resulting in a rapid coupling
between the macroscopic and kinetic scales and a mixture of collisional and
collisionless dynamics. The new phases involving multiple X-lines and
collisionless physics may be important for the emerging applications of
magnetic reconnection to accelerate charged particles beyond their thermal
speeds. A large number of heliophysical and astrophysical plasmas are surveyed
and grouped in the phase diagram: Earth's magnetosphere, solar plasmas
(chromosphere, corona, wind and tachocline), galactic plasmas (molecular
clouds, interstellar media, accretion disks and their coronae, Crab nebula, Sgr
A*, gamma ray bursts, magnetars), extragalactic plasmas (Active Galactic Nuclei
disks and their coronae, galaxy clusters, radio lobes, and extragalactic jets).
Significance of laboratory experiments, including a next generation
reconnection experiment, is also discussed.
0 Followers
·
78 Views
• Source
• "To maintain pressure anisotropy, the time between electron collisions must be long compared with the full transit time of a fluid element through the reconnection layer (Egedal et al. 2013; Le et al. 2015). As a valuable tool for displaying the various regimes of reconnection and their transitions , Daughton & Roytershteyn (2012) developed the reconnection phase diagram spanned by the Lundquist number S and the normalized system size λ with respect to the ion sound Larmor radius, ρ s = m i (T e + T i )/eB, or the ion skin depth, d i = c/ω pi , for strong and weak guide-field reconnection, respectively (Ji & Daughton 2011). A convenient way of representing the constraint for anisotropic pressure on a system is the condition S > 10(m i /m e )(L/d i ). "
##### Article: The Wisconsin Plasma Astrophysics Laboratory
[Hide abstract]
ABSTRACT: The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries which mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a 10 m$^3$, fully ionized, magnetic-field free plasma in a spherical geometry. Plasma parameters of $T_{e}\approx5-20$ eV and $n_{e}\approx10^{11}-5\times10^{12}$ cm$^{-3}$ provide an ideal testbed for a range of astrophysical experiments including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds, and more. This article describes the capabilities of WiPAL along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.
Journal of Plasma Physics 06/2015; 81(05). DOI:10.1017/S0022377815000975 · 0.74 Impact Factor
• ##### Article: Magnetic Reconnection, a Key Self-Organization Process in Laboratory and Astrophysical Plasmas: Recent Research Progress
[Hide abstract]
ABSTRACT: Magnetic reconnection is a phenomenon of nature in whichmagnetic field lines change their topology and convert magnetic energy to plasma particles by acceleration and heating. The process can stretch out over time or occur quite suddenly. It is one of the most fundamental processes at work in laboratory and astrophysical plasmas. Magnetic reconnection occurs everywhere: In solar flares; coronal mass ejections; the earth's magnetosphere; in the star forming galaxies; and in plasma fusion devices. This paper reviews the most recent progress in the research of magnetic reconnection.
Progress of Theoretical Physics Supplement 01/2012; DOI:10.1143/PTPS.195.167 · 1.25 Impact Factor
• Source
##### Article: Magnetic reconnection in high-energy-density laser-produced plasmas
[Hide abstract]
ABSTRACT: Recently, novel experiments on magnetic reconnection have been conducted in laser-produced plasmas in a high-energy-density regime. Individual plasma bubbles self-generate toroidal, mega-gauss-scale magnetic fields through the Biermann battery effect. When multiple bubbles are created at small separation, they expand into one another, driving reconnection of this field. Reconnection in the experiments was reported to be much faster than allowed by both Sweet-Parker, and even Hall-MHD theories, when normalized to the nominal magnetic fields self-generated by single bubbles. Through particle-in-cell simulations (both with and without a binary collision operator), we model the bubble interaction at parameters and geometry relevant to the experiments. This paper discusses in detail the reconnection regime of the laser-driven experiments and reports the qualitative features of simulations. We find substantial flux-pileup effects, which boost the relevant magnetic field for reconnection in the current sheet. When this is accounted for, the normalized reconnection rates are much more in line with standard two-fluid theory of reconnection. At the largest system sizes, we additionally find that the current sheet is prone to breakup into plasmoids.
Physics of Plasmas 05/2012; 19(5). DOI:10.1063/1.3694119 · 2.25 Impact Factor
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https://unstable.publiclab.org/questions/gabrielxp46/05-14-2018/could-anyone-tell-me-if-it-is-possible-to-use-the-homemade-spectrometer-to-analyze-a-sample-of-metal
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# Question: could anyone tell me if it is possible to use the homemade spectrometer to analyze a sample of metal?
gabrielxp46 asked on May 14, 2018 14:34
196 | 1 answers | #16346
I am interested in this aspect because I perform a survey with stainless steels and would like to know if it is possible to use the homemade spectrometer to obtain some metal data such as chemical composition and etc.
The instruments to do The testing you want are complicated. It's not that the spectrometer couldn't be used, but it would take a lot of work. Here is a little background.
The common way to do this is with analytical techniques, such as atomic absorption (AA), atomic emission (AE), or inductively coupled plasma ( ICP). All use a spectrometer or spectrophotometer, so it is possible. It's the extras the instruments have that make it hard.
The ICP takes high power and a plasma furnaces. It's not easy to do. They were in the \$100k range (base). That's the first one to eliminate.
The AA takes special lamps for each element analyzed. Sometimes you can combine multiple elements into one lamp, but not always. AE doesnt take the lamp, but it is often the less sensitive of the two.
With all three techniques, the metal must be prepped. This usually means just acid digestion, although it can be much more involved. All forms of the metal ( say chrome) must be in the same valence state. Sometimes, a fair number of chemical steps are required. Then the dissolved liquids are aspirated in a flame and the spectra is taken.
Many of the lines used in these techniques are in the UV. i.E. Zinc is usually analyzed at 213.9 nm. There are many interferences from flames, etc, that need to be worked through.
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https://math.iitm.ac.in/event/15
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## Department of Mathematics
Indian Institute Of Technology Madras , Chennai
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An introduction to Orbifolds
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Shellable Graphs
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Stanley- Reisner rings
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Hierarchical Matrix technique through the use of Low Rank Algebra 06-05-2019 Kandappan, Research Scholar, Department of Mathematics, IIT Madras
Symbolic Dynamics with the shift spaces
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Introduction to Boundary Layer Theory
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Period Three Implies Chaos
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https://tianle.website/
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I am a Ph.D. student at Princeton University. Before joining Princeton, I studied at Peking University (PKU) majoring in applied mathematics, while pursuing a double major in computer science. I was fortunate to be advised by Professor Liwei Wang on research about theory of machine learning. I spent a wonderful summer at MIT as a research intern supervised by Professor Sasha Rakhlin in 2019. I also work closely with Professor Jason D. Lee and Doctor Di He.
I have a very broad range of interests spanning many fields in machine learning, e.g., optimization, representation learning, architecture design (Transformer, Graph Neural Networks, etc.). To summarize in one sentence, I’m mostly interested in the theories that can inspire us to make better algorithms. My tenet is to make machine learning more general [1, 2, 3], efficient [5, 6, 9], and reliable [4, 7, 8] (please see my publications below).
If you are interested in collaborating with me or want to have a chat, always feel free to contact me through e-mail or WeChat : )
# News
• Graphormer wins first place in PCQM4M task of OGB-LSC @ KDD Cup 2021! June, 2021
• Three papers accepted by ICML 2021! May, 2021
• Two papers accepted by NeurIPS 2020! Sep. 2020
• Graduate from PKU. July, 2020
# Selected Publications
1. ## (Preprint) Do Transformers Really Perform Bad for Graph Representation?
Chengxuan Ying, Tianle Cai, Shengjie Luo, Shuxin Zheng, Guolin Ke, Di He, Yanming Shen, Tie-Yan Liu
Highlight: Make Transformer great again on graph classification by introducing three graph structural encodings! Achieve SOTA performance on several benchmarks! Winner solution of OGB-LSC challenge!!
[Code]
2. ## (Preprint) Towards a Theoretical Framework of Out-of-Distribution Generalization
Haotian Ye, Chuanlong Xie, Tianle Cai, Ruichen Li, Zhenguo Li, Liwei Wang
Highlight: We formulate what an OOD is and derive bounds and model selection algorithm upon our framework.
3. ## (ICML 2021) A Theory of Label Propagation for Subpopulation Shift
Tianle Cai*, Ruiqi Gao*, Jason D. Lee*, Qi Lei*
Highlight: Subpopulation shift is a ubiquitous component of natural distribution shift. We propose a general theoretical framework of learning under subpopulation shift based on label propagation. And our insights can help to improve domain adaptation algorithms.
[Slides]
4. ## (ICML 2021) Towards Certifying $\ell_\infty$ Robustness using Neural Networks with $\ell_\infty$-dist Neurons
Bohang Zhang, Tianle Cai, Zhou Lu, Di He, Liwei Wang
Highlight: New architecture with inherent $\ell_\infty$-robustness and a tailored training pipeline. Achieving SOTA performance on several benchmarks!
[Code]
5. ## (ICML 2021) GraphNorm: A Principled Approach to Accelerating Graph Neural Network Training
Tianle Cai*, Shengjie Luo*, Keyulu Xu, Di He, Tie-Yan Liu, Liwei Wang
Highlight: A principled normalization scheme specially designed for graph neural networks. Achieve SOTA on several graph classification benchmarks.
[Code], [Third-part implementation by microsoft ptgnn lab. (Thanks for the very quick reaction and implementation MS!)], [Slides]
6. ## (NeurIPS 2020) Sanity-Checking Pruning Methods: Random Tickets can Win the Jackpot
Jingtong Su*, Yihang Chen*, Tianle Cai*, Tianhao Wu, Ruiqi Gao, Liwei Wang, Jason D. Lee
Highlight: We sanity-check several existing pruning methods and find the performance of a large group of methods only rely on the pruning ratio of each layer. This finding inspires us to design an efficient data-independent, training-free pruning method as a byproduct.
[Code]
7. ## (NeurIPS 2020) Locally Differentially Private (Contextual) Bandits Learning
Kai Zheng, Tianle Cai, Weiran Huang, Zhenguo Li, Liwei Wang
Highlight: Simple black-box reduction framework improves private bandits bounds.
[Code]
8. ## (NeurIPS 2019 Spotlight 2.4 % Acceptance rate) Convergence of Adversarial Training in Overparametrized Networks
Ruiqi Gao*, Tianle Cai*, Haochuan Li, Liwei Wang, Cho-Jui Hsieh, Jason D. Lee
Highlight: For overparameterized neural network, we prove that adversarial training can converge to global minima (with loss 0).
[Slides]
9. ## (NeurIPS 2019 Beyond First Order Method in ML Workshop) Gram-Gauss-Newton Method: Learning Overparameterized Neural Networks for Regression Problems
Tianle Cai*, Ruiqi Gao*, Jikai Hou*, Siyu Chen, Dong Wang, Di He, Zhihua Zhang, Liwei Wang
Highlight: A provable second-order optimization method for overparameterized network on regression problem! As light as SGD at each iteration but converge much faster than SGD for real world application.
# Talks
• Label Propagation for Domain Adaptation at AI TIME [slides]
• Towards Understanding Optimization of Deep Learning at IJTCS [slides] [video]
• A Gram-Gauss-Newton Method Learning Overparameterized Deep Neural Networks for Regression Problems at PKU machine learning workshop [slides]
# Experience
• Visiting Research Student at Simons Institute, UC Berkeley
• Program: Foundations of Deep Learning
• June, 2019 - July, 2019
• Visiting Research Internship at MIT
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https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Norway
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# 1911 Encyclopædia Britannica/Norway
NORWAY (Norge), a kingdom of northern Europe, occupying the W. and smaller part of the Scandinavian peninsula. Its E. frontier marches with that of Sweden, except in the extreme N., where Norway is bounded by Russian territory. On the N., W., S. and S.E. the boundary is the sea—the Arctic Ocean, that part of the Atlantic which is called the Norwegian Sea, the North Sea and the Skagerrack successively. The S. extremity of the country is the island of Slettingen in 57° 58' N., and the N. that of Knivskjærodden, off the North Cape in 71° 11' N. Of the mainland, the southernmost promontory is Lindesnæs, in 57° 59' N., while the northernmost is Nordkyn, in 71° 7' N. The S. of the country, that is to say, the projection between the Skagerrack and the North Sea proper, lies in the same latitude as the N. of Scotland and Labrador, and the midland of Kamchatka. The most western island, Utvær, lies off the mouth of the Sogne Fjord (4° 30' E.), and the easternmost point of the country is within the Arctic lands, near Vardö (31° 11' E). The direct length of Norway (S.W. to N.E.) is about 1100 m. The extreme breadth in the S. (about 61° N.) is 270 m., but in the N. it is much less—about 60 m. on the average, though the Swedish frontier approaches within 6 m. of a head-branch of Ofoten Fjord, and the Russian within 19 m. of Lyngen Fjord. The length of the coast line is difficult to estimate; measured as an unbroken line it is nearly 1700 m., but including the fjords and greater islands it is set down as 12,000. The area is estimated at 124,495 sq. m.
Physical Features. Relief.—The main mountain system of the Scandinavian peninsula hardly deserves its name of Kjölen[1] (the keel). It may rather be described as a plateau deprived of the appearance of a plateau, being on the one hand grooved by deep valleys, while on the other many salient peaks tower above its average level. Such peaks, during the later Glacial period, stood above the ice-field. Peaks and ridges were formed by the action of small glaciers cutting out each its circular hollow (botn) just as they still work on the remaining snow-fields. But where the power of the main ice-mass was at work, the characteristic rounded forms of base rock are seen, close above the sea along the coast, but even as high as 5000 ft. in some inland localities. The high plateau lies along the W. side of the peninsula, so that except in the S.E. Norway is mountainous throughout. Even the part excepted is hilly, but it partakes of the character of the long eastern or Swedish slope of the peninsula. Beyond the coast line their floors sink far below sea-level, and thus are formed the fjords and the belt of rugged islands which characterize almost the entire seaboard of Norway. Where Norway marches with Russia, a few heights exceed 3000 or even 4000 ft., but the land is not generally of great elevation. But from the point of junction with Swedish territory the mountains increase considerably in height. For a short distance, as far south as Lake Torne, the loftiest points lie within Norwegian territory, such as Jæggevarre (6283 ft.), between Lyngen and Ulfs fjords, and Kiste Fjeld (5653 ft.) farther inland. Thereafter the principal heights lie approximately along the crest-line of the plateau and within Swedish territory. Sulitelma, however (6158 ft.), lies on the frontier. Southward again the higher summits fall to Norway. S. of Bodö, Svartisen (“the black ice”), a magnificent snow-field bordering the coast, and feeding many glaciers, culminates at 5246 ft. Thereafter, Okstinderne or Oxtinderne (6273 ft.), and the Store Börge Fjeld (5587 ft.) are the principal elevations as far as 64° N. A little S. of this latitude the so-called Trondhjem depression is well marked right across the central upland, the height of the mountains not often exceeding 4000 ft., while the peaked form characteristic of the heights which rose clear of the glaciers of the later Glacial period is wanting. It is from this point too that Norwegian territory broadens so as to include not only the highest land in the peninsula, but a considerable part of the general E. and S.E. slope. The high plateau broadens and follows the S.W. sweep of the coast. Pursuing it S. the Dovre Fjeld is marked off by the valleys of the rivers Driva and Sundal, Laagen (or Laugen) and Rauma, and the fjords of the coast land of Nordmöre. Here Snehætta reaches a heightof 7615 ft., and the Romsdal (the name under which the Rauma valley is famous among tourists) is flanked by many abrupt jagged peaks up to 6000 ft. high. The valley of the Laagen forms the upper part of Gudbrandsdal. East of this and S.E. of the Dovre is another fjeld, Rondane, in which Högronden rises to 6929 ft. South of the Otta valley is Jotunheim or Jötun Fjeld, a sparsely peopled, in parts almost inaccessible, district, containing the highest mountains in Scandinavia, Galdhöpiggen reaching 8399 ft. On the seaward side of Jotunheim is Jostedalsbræ, a great snow-field in which Lodalskaupen reaches a height of 6795 ft. South of Sogne Fjord (61° N.) mountains between 5000 and 6000 ft. are rare; but in Hallingskarvet there are points about 6500 ft. high, and in the Hardanger Vidda (waste), a broad wild upland E. of Hardanger Fjord, Haarteigen reaches 6063 ft. The highland finally sinks towards the S. extremity of Norway in broken masses and short ranges of hills, separated by valleys radiating S.E., S. and W.
Glaciers.—The largest glacier in continental Europe is Jostedalsbræ, with an area of 580 sq. m., the snow-cap descending to 4000 or 4500 ft. Several of its branches fall nearly to the sea, as the Böiumsbræ above the Fjærland branch of Sogne Fjord. The largest branch is the Nigardsbræ. Skirting Hardanger Fjord, and nearly isolated by its main channel and two arms, is the great glacier of Folgefond (108 sq. m.). Two branches descending from the main mass are visited by many who penetrate the Hardanger—Buarbræ on the E., falling towards Lake Sandven above Odde, and Bondhusbræ on the W. The extreme elevation of the Folgefond in 5270 ft. Continuing N. other considerable snow-fields are those of Hallingskarvet, the Jotunheim, Snehætta in Dovre Fjeld, and Store Börge Fjeld at the head of the Namsen valley. Next follow Svartisen, second in extent to Jostedalsbræ (nearly 400 sq. m.), the Sulitelma snowfield and Jökel Fjeld, between Kvænang and Öxfjords. One glacier actually reaches the edge of Jökel Fjord, a branch of Kvænang Fjord, so that detached fragments of ice float away on the water. This is the only instance of the kind in Norway. The Seiland snow-field, on Seiland island near Hammerfest, is the most northerly névé in Europe. The snow-line in Norway is estimated at 3080 ft. in Seiland, 5150 ft. on Dovre Fjeld, and from 4100 to 4900 ft. in Jotunheim. The lowness of the snow-line adds to the grandeur of Norwegian mountains.
Coast.—The flanks of the plateau fall abruptly to the sea almost throughout the coast-line, and its isolated fragments Skjærgaard or island-fence. appear in the innumerable islands which fringe the mainland. This island fringe, which has its counterpart in a modified form along the Swedish coast, is called in Norwegian the skjærgaard (skerry-fence, pronounced shārgoord). This fringe and the fjord-coast are most fully developed from Stavanger nearly as far as the North Cape. The channels within the islands are of incalculable value to coast wise navigation, which is the principal means of communication in Norway. The voyage northward from Stavanger may be made in quiet waters almost throughout. Only at rare intervals vessels must enter the open sea for a short distance, as off the port of Haugesund, or when rounding the promontory of the Stat or Statland, S. of Aalesund, passing the coast of Hustadviken, S. of Christiansund, or crossing the mouth of some large fjord. At some points large steamers, following the carefully marked channel, pass in deep water between rocks within a few yards on either hand. Small ships and boats, fishing or trading between the fjord-side villages, navigate the ramifying “leads” (leder) in security. In some narrow sounds, however, the tidal current is often exceedingly strong. The largest island of the skjærgaard is Hindö of the Lofoten and Vesteraalen group. Its area is 860 sq. m. The number of islands is estimated at 150,000 and their area at 8500 sq. m. Many of them are of great elevation, especially the more northerly; thus the jagged peaks characteristic of Lofoten culminate at about 4000 ft. Hornelen, near the mouth of Nordfjord, 3000 ft. high, rises nearly sheer above the Fröjfjord, and vessels pass close under the towering cliff. Torghatten (“the market hat”), N. of Namsos, is pierced through by a vast natural tunnel 400 ft. above the sea; and Hestmandö (“horseman island”), on the Arctic circle, is justly named from its form. The dark blue waters of the inner leads and fjords are clouded, and show a milky tinge on the surface imparted by the glacier-fed rivers. Bare rock is the dominant feature of the coast and islands, save where a few green fields surround a farmstead. In the N., where the snow-line sinks low, the scenery at all seasons has an Arctic character.
Christiania Fjord, opening from the N. angle of the Cattegat and Skagerrack, differs from the great fjords of the W. Its Fjords. shores are neither so high nor so precipitous as theirs; it is shallower, and contains a great number of little islands. From its mouth, round Lindesnæs, and as far as the Bukken Fjord (Stavanger) there are many small fjords, while the skjærgaard provides an inner lead only intermittently. Immediately S. of Bukken Fjord, from a point N. of Egersund, the flat open coast of Jæderen, dangerous to shipping, fringing a narrow lowland abundant in peat-bogs for some 30 m., forms an unusual feature. Bukken Fjord is broad and island-studded, but throws off several inner arms, of which Lyse Fjord, near Stavanger, is remarkable for its extreme narrowness, and the steepness of its lofty shores. The Hardanger Fjord, penetrating the land for 114 m., is known to more visitors than any other owing to its southerly position; but its beauty is exceeded by that of Sogne Fjord and Nord Fjord farther N. Sogne is the largest and deepest fjord of all; its head is 136 m. from the sea, and its extreme depth approaches 700 fathoms. Stor Fjord opens inland from Aalesund, and one of its head branches, Geiranger Fjord, is among the most celebrated in Norway. Trondhjem Fjord, the next great fjord northward, which broadens inland from a narrow entrance, lacks grandeur, as the elevation of the land is reduced where the Trondhjem depression interrupts the average height of the plateau. The coast N. of Trondhjem, though far from losing its beauty, has not at first the grandeur of that to the south, nor are the fjords so extensive. The principal of these are Namsen, Folden and Vefsen, at the mouth of which is Alsten Island, with the mountains called Syv Söstre (Seven Sisters), and Ranen, not far S. of the Arctic circle. Svartisen sends its glaciers seaward, and the scenery increases in magnificence. Salten Fjord, to the N. of the great snow-field, is connected with Skjerstad Fjord by three narrow channels, where the water, at ebb and flow, forms powerful rapids. The scenery N. of Salten is unsurpassed. The Lofoten and Vesteraalen islands are separated from the mainland by the Vest Fjord, which is continued inland by Ofoten Fjord. If these two be considered as one fjord, its length is about 175 m., but the actual penetration of the mainland is little more than a fifth of this distance. The main fjords N. of Vesteraalen have a general northerly direction; among them is Lyngen Fjord near Tromsö, with high flanking cliffs and glaciers falling nearly to the sea. Alten Fjord is remarkable for the vegetation on its shores. From Lofoten N. there is a chain of larger islands, Senjen, Kvalö, Ringvadsö, Sorö, Stjernö, Seiland, Ingö and Magerö. These extend to the North Cape, but hereafter the skjærgaard ends abruptly. The coast to the E. is of widely different character; flat mountain wastes descend precipitously to the sea without any islands beyond, save Vardö, with two low islets at the E. extremity of Norway. The fjords are broader in proportion to their length. The chief are Porsanger, Laxe and Tana, opening N., and Varanger opening E. N. of this fjord the land is low and the landscape monotonous; on the S. a few island and branch fjords break the line of the shore.
Stavanger Fjord has an extreme depth of 380 fathoms; Hardanger Fjord 355, Sogne Fjord 670, Nordfjord 340, Trondhjem Fjord 300, Ranen Fjord 235, Vestfjord 340, Alten Fjord 225, and Varanger Fjord 230. Marine terraces are met with in the E. of the country, and near Trondhjem, at 600 ft. above sea-level; and they are also seen at a slighter elevation at the heads of some western fjords. Moreover, at some points (as on the Jæderen coast) “giant kettles” may be observed close to sea-level, even below the level of high tide; and these glacial formations indicate the greater elevation of the land towards the close of the Glacial epoch. Former beach-lines are most commonly to be observed in northern Norway (e.g. in Alten Fjord), and in some cases there are two lines at different altitudes. The land above the raised beach is generally bare and unproductive, and human habitation tends to confine itself in consequence to the lower levels.
Hydrography.-In S.E. Norway there are long valleys, carrying rivers of considerable size, flowing roughly parallel but sometimes uniting as they approach the sea. The Glommen, rising N. of Röros in Aursund Lake, and flowing with a southerly curve parallel with the frontier for 350 m. to the Skagerrack, is the largest river in the Scandinavian peninsula. Its upper middle valley is called Österdal,[2] the richest timber district in Norway. Its drainage area is 16,000 sq. m. Seven miles above its mouth it forms the fine Sarpsfos, and not far above this it traverses the large lake Öieren. A right bank tributary, the Vormen, has one of its sources (under the name of Laagen) in Lake Lesjekogen, which also drains in the opposite direction by the Rauma. The stream, after watering Gudbrandsdal, enters Mjösen, the largest lake in Norway. It is 60 m. long, but, like most of the greater Norwegian lakes, has no great breadth. It has, however, an extreme depth of 1500 ft. The Drammen river, which enters a western arm of Christiania Fjord below the town of Drammen, is the common outlet of several large rivers. The Hallingdal river drains the valley of that name, and forms Lake Kröderen, which is connected with the Drammen river by the Snarum. A short distance above the junction the Drammen flows out of Lake Tyrifjord, 50 sq. m. in area, into which flow the united waters of the Rand, from the valley district of Valdres, and the Bægna. The whole basin of the Drammen has an area of 6600 sq. m. The rivers between Christiania Fjord and Lindesnæs preserve the characteristics of those of the Glommen and Drammen systems. They rise on the Hardanger Vidda or adjacent uplands. The most important are the Laagen (to be distinguished from the river of that name in Gudbrandsdal), draining the Numedal; the Skien, the Nid and the Otter. Lakes are very numerous, the chief, beyond those already named, being Nordsjö on the Skien river, Tinsjö in the same system, which receives the river Maan, famous as forming the Rjukanfos (smoking fall) of 415 ft., and Nisservand on the Nid. The larger lakes lie, with a certain regularity, at elevations about 400 ft. above the sea, and it is considered that their basins were the heads of fjords when the land lay at a lower level, and were formed during an earlier glacial period than the present fjords. The great Lake Fæmund, lying E. of the Glommen valley and drained by the river of the same name, which becomes the Klar in Sweden, to which country it mainly belongs, is similar in type to the lakes of the northern highlands of Sweden. The streams of the coast of Jæderen reach the sea through sluggish channels, brown with peat.
Not only do the valleys of the W. far surpass in beauty those of the S. and E., but they carry streams of much greater volume in proportion, owing to the heavier average rainfall of the W. slope. The first to be noted is that of the Sand or Logen river, a brilliant, rapid stream, famous for its salmon-fishing, which debouches at Sand into Sands fjord. The valley which opens from Odde at the head of a branch (Sör fjord) of Hardanger Fjord, is noted as containing two of the finest waterfalls in Norway. The one, Lotefos (which is joined by the smaller Skarsfos), is a powerful cataract following a tortuous cleft. The other, Espelandsfos, is formed by a very small stream; it falls quite sheer and spreads out like a fine veil. The only other considerable river entering Hardanger Fjord is the Bjoreia, with its mouth at Vik in Eidfjord. On this stream is the magnificent Vöringsfos. Lesser streams within the basin of the Hardanger form the Skjæggedal and several other beautiful falls. From Hardanger N. to Romsdal the streams of the W. slope are insignificant, but there are several splendid valleys, such as the sombre Nærödal, which descends to the Næro branch of Sogne Fjord, or the valleys which sink S. and N. from the Jostedalsbræ to the head branches of Sogne Fjord and Nordfjord respectively. Above those of Nordfjord is a series of lakes, Olden, Loen and Stryn, whose milky waters are supplied almost directly from the Jostedal glaciers, while above Eidsfjord a corresponding trough contains Lake Hornindal. The next important valley is the Romsdal, the stream of which, the Rauma, forms the W. outlet of Lake Lesjekogen, as the Laagen forms the E. This lake, which lies 2011 ft. above sea-level, is the most remarkable example of an indefinite watershed to be found in S. Norway. N. from Romsdal the Driva debouches into Sundals Fjord, while the Orkla, draining Orkedal, the Gula draining Guldal, and the Nea or Nid, draining Lake Selbu, and
forming the Lerfos, enter Trondhjem Fjord from the S., and range in length from 70 to 100 m. The Stjördal, a beautiful wooded valley, leads up from the fjord to the lowest pass over the Trondhjem depression (at Storlien), and is followed by the railway from Trondhjem into Sweden.
N. of Trondhjem Fjord, in spite of the close proximity of the mountains to the W. coast, several considerable rivers are found, flowing generally about N.E. or S.W. in valleys nearly parallel to the coast. Such are the Namsen (85 m. in length) and the Vefsen, discharging into Namsen Fjord and Vefsen Fjord respectively, and the Dunderland, flowing into Ranen Fjord. In the basin of the same fjord is the short Rös river, which drains Rös Vand, second in extent of the Norwegian lakes. In the extreme N., where the coastward slope is longer, there are such large rivers as the Alten, 98 m. long, discharging into the fjord of that name, and the Tana, also giving name to the fjord into which it flows, and forming a reat part of the Russo-Norwegian frontier. It is 180 m. long, and drains an area of 4000 sq. m.
Though the lakes of Norway are not comparable with those of Sweden as regards either number or size, they are very numerous and are estimated to cover somewhat less than one-fortieth of the total area.
Glacial Action.—While the coast is considered to owe its fjords and islands to the work of former great glaciers, the results are even more patent inland. The actual tracks of the old glaciers are constantly to be traced. Nowhere are the evidences of glacial action better illustrated than in the barren tract behind the low coastal belt of Jæderen. Here are vast expanses of almost naked rock, often riven and piled up in fantastic forms; numerous small lakes or bogs occupy the rock basins, and vast numbers of perched blocks are seen, frequently poised in remarkable positions. The great valleys of Norway are of U-section and exhibit the irregular erosive action of the glaciers, as distinct from the regular action of the rivers. If a main glacier, after working steadily in the formation of its trough for a considerable distance, be imagined to receive an accretion of power at a certain point, it will begin from that point to erode more deeply. The result of such action is seen in the series of ledges over which the main rivers of Norway plunge in falls or rapids.
Geology.—Norway consists almost entirely of Archaean and Lower Palaeozoic rocks, imperfectly covered by glacial and other recent deposits. The whole of the interval between the Devonian and the Glacial periods is represented, so far as is known, only by a small patch of Jurassic beds upon the island of Andö. An archaean zone stretches along the W. coast from Bergen to Hammerfest, interrupted towards the N., by overlying patches of Palaeozoic deposits. Gneiss predominates, but other crystalline rocks occur subordinately. The Lofoten Islands consist chiefly of eruptive granite, syenite and gabbro. S. of a line drawn from the head of the Hardanger Fjord to Lake Mjösen is another great Archaean area. Here again gneiss and granite form the greater part of the mass, but in Telemarken there are also conglomerates, sandstones and clay-slates which are believed to be Archaean. Between these two Archaean areas the Lower Palaeozoic rocks form a nearly continuous belt which follows approximately the watershed of the peninsula and extends from Bergen and Stavanger on the S. to the North Cape and Vardo in the N. They occur also as a broad strip inlaid in the Archaean floor, from the Christiania Fjord northward to Lake Mjösen. A line drawn from the Nase to the North Cape coincides roughly with a marked change in the character and structure of the Palaeozoic beds. East of this line even the Cambrian beds are free from over folding, over thrusting regional metamorphism. They lie flat upon the Archaean floor, or have been faulted into it in strips, and they are little altered except in the neighbourhood of igneous intrusions. W. of the line rocks have been folded and metamorphosed to such an extent that it is often difficult to distinguish the Palaeozoic rocks from the Archaean. They form in fact a mountain chain of ancient date similar in structure to the Alps or the Himalayas. The relations of the two areas have been studied by A. E. Törnebohm in the Trondhjem region, and he has shown that the western mass has been pushed over the eastern upon a great thrust-plane. The relations, in fact, are similar to those between the Dalradian schists of the Scottish Highlands and the Cambrian beds of the W. coast of Sutherland. In Scotland, however, it is the eastern rocks which have been pushed over the western. Corresponding with the difference in structure between the E. and the W. regions there is a certain difference in the nature of the deposits themselves. In the Christiania district the Cambrian, Ordovician and Silurian beds consist chiefly of shales and limestones. Farther north sandstones predominate, and especially the Sparagmite, a felspathic sandstone or arkose at the base of the Cambrian; but the deposits are still sedimentary. In the Trondhjem district, on the other hand, belonging to the folded belt, basic tuffs and lavas are interstratified with the normal deposits, showing that in this region there was great volcanic activity during the early part of the Palaeozoic era. In both the E. and the W. region the Devonian is probably represented by a few patches of red sandstone, in which none but obscure remains of fossils have yet been found. It may be noted here that in the extreme N. of Norway, E. of the North Cape, there is a sandstone not unlike the Sparagmite of the S., which is said by Reusch to contain ice-worn pebbles and to rest upon a striated pavement of Archaean rocks.
The Mesozoic era is represented only by the sandy deposits with seams of lignite which occur on the island of Andoën in the Vesteraalen. They contain remains of plants and have been correlated with the Lower Oolite of Great Britain. No Tertiary beds have been found, but Pleistocene deposits of various kinds are met with. The evidences of ice action during the Glacial Period are conspicuous over the whole country and are similar to those in other glaciated regions. But the most remarkable features produced in recent geological times are the terraces which appear as if ruled on the sides of the valleys and fjords. They are partly platforms cut in the solid rock and partly accumulations of gravel and sand like a modern beach, and they were evidently formed by the action of waves. Some of them contain marine shells of living species and mark the former position of the sea-level; but others are of more doubtful origin and may indicate the shores of lakes formed by the damming of the lower part of the fjords by means of glaciers, as in the case of the Parallel Roads of Glen Roy. They occur at various levels, and have been observed as high as 3000 ft. above the sea.
Emery Walker sc.
No volcanic rocks of modern date are known in Norway, but great intrusions of igneous rock took place in early geological times. Amongst them may be mentioned the gabbro of the Jotunfjeld, and the elaeolite syenites and associated rocks of the Christiania region. The latter form the subject of a valuable series of memoirs by Brögger, who shows that they have all been derived from a single magma, and that the differentiation of this magma led to the production of several different types of rock.
(P. La.)
Meteorology.—The most powerful influence on the climate of Norway is that of the warm drift across the Atlantic Ocean from the Temperature. S.W. The highest mean annual temperature in Norway is found on the S. and W. coasts, where it ranges from 44.5° to 45.5° F., and the lowest is found at Karasjok and Kautokeino, lying at elevations of 430 and 866 ft. respectively in Finmarken, near the Russian frontier. Here the mean temperature is 26.4°, while at Vardö, on the north coast, it is 33°. At Röros (2067 ft.) at the head of the Glommen valley, and at Fjeldberg (3268 ft.) in the upper Hallingdal, the mean annual temperature is 31°. The longest winter is found in the interior of Finmarken, 243 days with a mean temperature below 32° being recorded at
Kautokeino, contrasted with 205 at Vardö. In the S. uplands (as at Fjeldberg) there is an average of 200 such days, and at Christiania about 120. On the S.W. coast there is no day of which the mean temperature falls below 32°; the most westerly insular stations, however, such as Utsire and Skudeness off Bukken Fjord, record frost during some part of 60 days. The lowest winter average temperature is found in a centre of cold in the N. which extends over Swedish and Russian territory as well as Norwegian. The Norwegian station of Karasjok, within it, records 4° during December, January and February, and in this area there have also been observed the extreme minima of temperature in the country, e.g. 60.5° below zero at Karasjok. The contrast with the S.W. coast may be continued. Here at some of the island stations, the coldest month, February, has an average about 35°, and the lowest temperature recorded at Ona near Christiansund is 10.5°. It may be noted here that in several cases the lower-lying inland stations in the south show a distinctly lower winter temperature than the higher in the immediate vicinity. Thus the average for Röros (2067 ft.), 13°, contrasts with 11° for Tönset; at Listad in Gudbrandsdal (909 ft.) it is 16.5°, but at Jerkin in the Dovre Fjeld (3160 ft.) it is 17.5°. The summer is hottest in S.E. Norway (Christiania, July, 62.5°). On the other hand, the lowest summer average in the interior of Finmarken is not less than 53.5° in July; but at Vardö it is only 48° in August, usually the warmest month on this coast. In the lofty inland tracts of the S.E. the July temperature ranges, from 59° in the valleys, to as low as 49° at the high station of Jerkin. The interior having a warm summer and a cold winter, and the coast a cool summer and a mild winter, the annual range of temperature is remarkably greater inland than on the coast.
An important result of the warm Atlantic drift is that the fjords are not penetrated by the cold water from the lower depths of the outer ocean, and in consequence are always ice-free, except in winters of exceptional severity in the innermost parts of fjords, and along shallow stretches of coast.
The sun is above the horizon at the North Cape continuously from the 12th of May to the 29th of July, and at Bodö, not far from the The “midnight sun.” Arctic circle, from the 3rd of June to the 7th of July. Even at Trondhjem there is practically full daylight from the 23rd of May to the 20th of July. Even in the extreme S. of Norway there is no darkness from the end of April to the middle of August. In winter, on the other hand, the sun does not rise above the horizon at the North Cape from the 18th of November. to the 23rd of January, and at Bodö from the 15th to the 27th of December. There is only a twilight at midday. In the extreme S. the sun is above the horizon for 6½ hours at mid-winter.
The prevailing winter winds are from the land seaward, while the system is reversed in summer. The winds in Norway Winds. may therefore be roughly classified according to locality thus:—
South-east Coast(Skagerrack). West Coast. North. Winter N.E. S. S.W. Summer S.W. to W. N. N.
The force of the wind is greater in winter on the coast; inland, on the contrary, the winter is normally calm; and at all seasons, on the average, the periods of calm are longer inland than on the coast. The average annual number of stormy days, however, ranges from ten to twenty on the S. coast, from forty-five to sixty-two on the coast of Finmarken, and sixty to seventy at Ona; whereas in the interior of Finmarken the average number is four, while in the S. inland districts stormy days are rare. December and January are the stormiest months. Hailstones are rare and seldom destructive. Thunderstorms are not frequent. They reach a maximum average of ten annually in the Christiania district.
The number of days on which rain or snow falls is greatest on the coast from Jæderen to Vardö, least in the S.E. districts and the interior of Finmarken. At the North Cape, in Lofoten, and along the W. coast between the Stad and Sogne Fjord, precipitation occurs on about 200 days in the year, although by contrast in the inner part of Sogne Fjord there is precipitation only on 121 days. On Dovre Fjeld and the SE; coast the average is about 100 days. Snowfall occurs least frequently in the S. (e.g. at Mandal, 25 snowy days out of 116 on which precipitation occurs), increasing to 50 at Christiania, or Dovre Fjeld, and about the mouth of Trondhjem Fjord, to 90 at Vardö, and to 100 at the North Cape. From Vardö to the Dovre Fjeld and in the upland tracts, snow occurs at least as frequently as rain. Snowfall has been recorded in all months on the coast as far S. as Lofoten. The amount of precipitation is greatest on the coast, where, at certain points on the mainland between Bukken Fjord and Nordfjord, an annual average of 83 in. is reached or even exceeded. On the outer islands there is a slight decrease; inland the decrease is rapid and great. In Dovre Fjeld a minimum of 12 in. is found. In the extreme S. of the country the average is 39 in., N. of Trondhjem Fjord 53 in. are recorded, and there is a well-marked maximum of 59 in. at Svolvær in Lofoten, N. of which there is a diminution along the coast to 26 in. at the North Cape. In the northern interior a minimum of 16 in. is recorded. Strongly marked local variations are observed.
The amount of cloudiness is on the whole great. The coast of Finmarken has over three cloudy days to one clear day; in the interior of the country clear and cloudy days are about equally divided. Fog is most frequent on the W. and N.W. coasts in summer; on the S.E. coast in winter. In winter a frosty fog often occurs about the heads of the fjords during severe cold or with a breeze from the land.
Flora.—The forests of Norway consist chiefly of conifers. The principal forest regions are the S.E. and S. Here, in the Trondhjem district, and in Nordland there are extensive forests of pine and fir. In the coastal and fjord region of the W. the pine is the only coniferous forest tree, and forests are of insignificant extent. In S. Norway the highest limit of conifers is from 2500 to 3000 ft. above sea-level; in the inland parts of the Trondhjem region it is from 1600 to 2000 ft. (though on the coast only from 600 to 1200); farther N. it falls to 700 ft. about 70° N. The birch belt reaches 3,000 to 3500 ft. Next follow various species of willows, and the dwarf birch (betula nana), and last of all, before the snow-line, the lichen belt, in which the reindeer moss (cladonia rangiferina) is always conspicuous. A few trees of the willow belt sometimes extend close up to the snow-line. In the S. and less elevated districts the lowest zone of forests includes the ash, elm, lime, oak, beech and black alder; but the beech is rare, flourishing only in the Laurvik district. The snow ranunculus and the Alpine heather are abundant. The Dovre Fjeld is noted as the district in which the Arctic flora may be studied in greatest variety and within comparatively narrow limits. On the coastal banks the marine flora is very finely developed.
Fauna.—The great forests are still the haunt of the bear, the lynx, and the wolf. Bears are found chiefly in the uplands N. of Trondhjem, in the Telemark and the W. highlands, but the cutting of forests has limited their range. The wolves decreased very suddenly in S. Norway about the middle of the 19th century, probably owing to disease, but are still abundant in Finmarken, and the worst enemy of the herds of tame reindeer. The elk occurs in the eastern forests, and northward to Namdal and the Vefsen district. The red deer is confined chiefly to the W. coast districts; its principal haunt is the island of Hitteren, off the Trondhjem Fjord. On the high fields are found the wild reindeer, glutton, lemming and the fox (which is of wide distribution). The wild reindeer has decreased, though large tame herds are kept in some parts, especially in the N. The lemming is noted for its curious periodic migrations; at such times vast numbers of these small animals spread over the country from their upland homes, even swimming lakes and fjords in their journeys. They are pursued by beasts and birds of prey, and even the reindeer kill them for the sake of the vegetable matter they contain. Hares are very common all over Norway up to the snow-line. The beaver still occurs in the Christiansand district.
Game birds are fairly abundant in most districts. The most notable are the two sorts of rype, the skov or dal rype (willow grouse, Avifauna. lagopus albus) and the fjeld rype (lagopus alpina). Black grouse are widely distributed; hazel grouse are found mainly in the pine forests of the E. and N., as are capercailzie. Woodcock and snipe are fairly common. The partridge is an immigrant from Sweden, and occurs principally in the E. and S.E. A severe winter occasionally almost exterminates it. A very large proportion of the Norwegian avifauna consists of geese and ducks, various birds of prey, golden plover, &c. These birds, at the autumn migration, leave by three well-defined routes—one from Finmarken into Finland, one by the Christiania valley, and one by the W. coast, where they congregate in large numbers on the lowlands of Jæderen. The Lapland bunting and snow bunting (plectrophanes laponica and nivalis), the snowy owl (mgetea scandiaca) and rough-legged buzzard (archibuteo lagopus) and sea-birds are exceedingly numerous. In some localities such birds as the puffin and kittiwakes form great colonies (fugleberge, bird cliffs).
The common seal is very frequent; and arctic seals and occasionally the Walrus visit the northern coasts; among these the harp seal Marine fauna. (phoca groenlandica) is believed to be particularly destructive to the fisheries. These last are of great importance; a large number of the best food-fisheries occur along the coasts, including cod, herring, mackerel, coal-fish, &c. The basking shark was formerly of some economic importance; the Japanese shark, a strictly local variety, also occurs in the neighbourhood of Vardö. Various small species of whales visit the coast; among these the lesser rorqual may be mentioned, as an antique method of hunting it with bow and arrows is still practised in the neighbourhood of Bergen. In the fjords many invertebrates as well as fish are found. Of fresh-water fish the salmonidae are by far the most important. Next to these, perch, pike, gwyniad and eel are most common.
As regards insect life, Norway may be divided into three areas, the S. being richer than the W., while the N. is distinct from either in the number of peculiarly arctic insects.
Sport.—Norway is much frequented by British anglers. Moderate rod-fishing for trout is to be obtained in many parts. But most of the owners of water rights have a full appreciation of the value of good fishing to sportsmen, especially when netting rights are given up for the sake of rod-fishing. The same applies to good shooting. Foreigners may not shoot without a licence, the cost of which is 100 kroner (£5 : 11 : 0) whether on crown lands or on private properties, whose owners always possess the shooting rights.
Population.—The resident population of Norway in 1900 was 2,221,477. The Table shows the area and population of each of the administrative divisions (amt, commonly translated “county”). Norway is, as a whole, the most thinly populated of the political divisions of Europe. It may be noted for the sake of comparison that the density of population in the most sparsely populated English county, Westmorland, is about equalled by that in Smaalenene amt (85 per sq. m.), and considerably exceeded in Jarlsberg and Laurvik amt (112.7 per sq. m.), but is not nearly approached in any other Norwegian county. The two counties named are small and lie almost wholly within the coastal strip along the Skagerrack, which, with the coast-lands about Stavanger, Haugesund, Bergen and Trondhjem, the outer Lofoten Islands and the land about Lake Mjösen, are the most thickly populated portions of the country, the density exceeding 50 persons per sq. m. A vast area practically uninhabited, save in the N. by nomadic Lapps, reaches from the north most point of the Norwegian frontier as far S. as the middle of Hedemarken, excepting a markedly more populous belt across the Trondhjem depression. Thus of the counties, Finmarken is the least thickly populated (1.8 per sq. m.). In such highland regions as Jotunheim and Hardanger Vidda habitations are hardly less scanty than in the N. About two-thirds of the population, then, dwell by the coast and fjords, and about one-quarter in the inland lowlands, leaving a very small upland population. The rural and urban populations form respectively about 76 and 24% of the whole. Of the chief towns of Norway, Christiania, the capital, had a population in 1900 of 229,101, Bergen of 72,179, Trondhjem of 38,156, Stavanger of 30,541, Drammen of 23,093. The towns with populations between 15,000 and 10,000 are Christiansand, Fredrikstad, Christiansund, Fredrikshald, Aalesund, Skien, Arendal and Laurvik. All these are ports.
Amter. Population 1900. Area in sq. m. Southern— Smaalenene 136,167 1,600 Akershus 116,896 2,054 Christiania (city) 229,101 6.5 Buskerud 112,743 5,789 Jarlsberg and Laurvik 101,003 896 Bratsberg 98,298 5,863 Nedenes 75,925 3,608.5 Lister and Mandal 78,259 2,804 South-eastern (inland)— Hedemarken 126,703 10,618 Christians 116,280 9,790 Western— Stavanger 125,658 3,530.5 South Bergenhus 132,687 6,024.5 Bergen (city) 72,179 5.5 North Bergenhus 88,214 7,130 Romsdal 136,519 5,786 South Trondhjem 134,718 7,182 Northern— North Trondhjem 83,449 8,788.5 Nordland 150,637 14,513 Tromsö 72,966 10,131 Finmarken 33,387 18,291
The population of Norway in 1801 was returned as 883,038. A rapid increase obtained from 1815 to 1835, a lesser increase thereafter till 1865, and a very slight increase till 1890. The second half of the 19th century, down to 1890, was the period of heaviest emigration from Norway. The vast majority of Norwegian emigrants go to the United States of America. But emigration slackened in the last decade of the 19th century, during which period the movement from rural districts to towns, which had decreased from about the middle of the century, revived. The number of Norwegians abroad may be taken at 350,000. The Lapps, commonly called Finns by the Norwegians, and confined especially to Finmarken (which is named from them), are estimated at 1% of the population. There are also a few Finns (about half the number of Lapps), whom the Norwegians call Kvæner, a name of early origin. The excess of births over deaths, about as 1.4 to 1, is much above the European average; the death-rate is also unusually low. The number of marriages is rather low, and the average age of marriage is high. The percentage of illegitimacy has shown some increase, but is not so high as in Sweden or Denmark. The percentage of longevity is high. The preponderance of females over males (about 1073 to 1000) is partly accounted for by the number of males who emigrate. The higher mortality of males is traced in part to the dangers of a seafaring life.
Down to the middle of the 19th century drunkenness was a strongly-marked characteristic of Norwegians. A strict licensing system was then introduced with success. Local boards were given a wide control over the issue of licences, and in 1871 companies (samlag) were introduced to monopolize and control the retail trade in spirits. Their profits do not, as in the Gothenburg system, go to the municipal funds, but are applied directly to objects of public utility. In 1894 a general referendum resulted in the entire prohibition of the sale of spirits in some towns for five years. The control of retail trade in beer and wine by the samlag has been introduced to some extent.
In Norway a strongly individual national character is to be expected, combined with conservatism of ancient customs and practices. The one finds no better illustration than the individuality of modern Norwegian music and painting. The other is still strong. Such customs as the lighting of the midsummer fires and the attendant celebrations still survive. Peculiar local costumes are still met with, such as those associated with weddings. In the coast wise shipping trade and the fisheries of the north, high-prowed square-sailed boats are frequently employed which are the direct descendants of the vessels of the early Vikings. Some examples of the ancient farmstead, composed of a group of wooden buildings each of a single chamber, are preserved, and medieval ornamental woodwork is met with. Wood is the principal building material except in some larger towns where brick and stone have superseded it. Where this is not the case, fires have left few, if any, ancient domestic buildings, but the preservation of ancient models in wooden houses makes Norwegian towns peculiarly picturesque. Norway retains a few highly interesting examples of ecclesiastical architecture. There are the peculiar small wooden churches (stavekirke) dating from the 11th to the 14th century, with high-pitched roofs rising in tiers so as to give the building something of the form of a pyramid. The roofs are beautifully shingled in wood. The wall timbers are vertical. To protect them from the weather, the roofs overhang deeply, and the lowest sometimes covers a species of external colonnade. The carving is often very rich. The most famous of these churches is that of Borgund near Laerdalsören; another fine example is at Hitterdal on the Kongsberg-Telemark road. On the other hand there are a few Romanesque and Gothic stone churches. In some of these the influence of English architecture is clear, as in the metropolitan cathedral of Trondhjem and the nave of Stavanger cathedral. St Mary's Church at Bergen, however, tends towards the French models. A good example of the smaller stone church is at Vossevangen, and there are several of Late Romanesque character in the Trondhjem district. There are ruins of a cathedral at Hamar, and a few monastic remains, as at Utstein, north of Stavanger, and on the island of Selje off Statland. Remains of pure Early English work are occasionally found, as at Ogne in Jæderen, but the later Gothic styles were not developed in Norway.
Tourist Traffic and Communications.—During the later decades of the 19th century Norway was rapidly opened up to British, American and German visitors. Passenger communications from Routes. Great Britain are maintained chiefly between Hull and Stavanger, Bergen, Aalesund, Christiansund and Trondhjem; Hull, Christiansand and Christiania; Newcastle and Stavanger, Bergen and the North; London and Christiania, &c, and there are also passenger services from Grimsby, Grangemouth and other ports. Yachting cruises to the great fjords and the North Cape are also provided. A daily service of mail steamers works between Christiania and all ports to Bergen; thence the summer service is hardly less frequent to Trondhjem. From each large port small steamers serve the fjords and inner waters in the vicinity, and there are also
The main roads of Norway, the construction of which has demanded the highest engineering skill, were not brought into existence until the last half of the 19th century. A Highways Act of 1851 placed the roads under the immediate control of local authorities, but government grants are made for the construction not only of main roads, but in many cases of cross-roads also. In a country where railways are few, posting is of prime importance, and in Norway the system is well developed and regulated. Along all main roads there are posting stations (skydsstationer, pronounced shüssstashöner), hotels, inns or farms, whose owners are bound to have horses always in readiness; at some stations on less frequented roads time is allowed for them to be procured. Posting stations are under strict control and the tariff is fixed. The vehicles are the stolkjærre (pronounced approximately stolchārer) for two passengers, and the kariol or carriole for one. A similar posting system obtains by rowing-boats on lakes and fjords.
The first railway, that between Christiania and Eidsvold, was constructed by agreement between British capitalists and the Railways. Norwegian government, and opened in 1854. The total length of railways is only about 1600 m., Norway having the lowest railway mileage in proportion to area of any European state, though in proportion to population the length of lines is comparatively great. Almost the whole are state lines. Railways are most fully developed in the S.E., both N. and S. of Christiania. The principal trunk line connects Christiania with Trondhjem by way of Hamar and the Osterdal, Röros and Stören. Four lines cross the frontier into Sweden—from Christiania by Kongsvinger (Kongsvinger railway) and by Fredrikshald (Smaalenenes railway), from Trondhjem by Storlien (Meraker railway), and from Narvik on Ofoten Fjord, the most northerly line in the world. Among other important lines may be mentioned that serving Lillehammer, Otta, &c., in Gudbrandsdal, that running S.W. from Christiania to Drammen, Skien and Laurvik; the Sætersdal line N. from Christiansand; the Jæderen line from Stavanger to Egersund and Flekkefjord; the Bergen-Vossevangen line; and the branch from Hell on the Meraker railway northward to Levanger. These local lines form links in important schemes for trunk lines. Norwegian railways are divided between the standard gauge and one of 3 ft. 6 in.; on the N. line a change of gauge is made at Hamar.
Some of the large lakes form important channels for inland Canals. navigation; the rivers, however, are not navigable for any considerable distance. A canal from Fredrikshald gives access N. to Skellerud, and the Bandaks canal connects Dalen in the Telemark with Skien.
The post-office is well administered, and both telegraph and telephone systems are exceptionally extensive.
Industries. Agriculture.—About 70% of the total area of Norway is barren, and about 21% is forest land, but the small agricultural area employs, directly or indirectly, about 40% of the population. The great majority of the peasantry are freeholders. Legislation has provided for the retention of landed property by families to which it has belonged for any considerable period—thus, under certain conditions, a family which has parted with land can reacquire it at an appraisement—or land alienated by its owner may on his death be acquired by his next of kin. The chief crops are oats barley, potatoes, mangcorn (a mixed crop of oats and barley), rye and wheat, the last being little cultivated. Cattle and sheep are kept in large numbers. Farmers commonly hold upland summer pastures together with their lowland farms, and in the open season frequently occupy a sæter (upland farmstead) and devote themselves to dairy work. Norwegian horses are small and thick-set, and remarkably surefooted. In the north large herds of reindeer are kept by Lapps. There is an agricultural college and model farm at Aas near Christiania.
Forestry.—Forest industries are confined chiefly to the S.E. and to the Trondhjem-Namsen district. Lumbering is an important industry. Forestry is controlled by the Department of Agriculture, and its higher branches are taught at the Aas college.
Fisheries.—The sea fisheries are of high economic importance. The principal are the cod fisheries. In March and April the cod shoal on the coastal banks for the purpose of spawning, and this gives rise to the well-known fishery for which the Lofoten Islands are the principal base. In April and May shoals of capelan appear off Finmarken, followed by cod and other fish, small whales, &c., which prey upon them; this affords a second fishery. For herring there is a spring fishery off Stavanger and Haugesund, and one in November and December off Nordland. Mackerel fisheries are important from Trondhjem Fjord S. to the Skagerrack. Salmon and sea-trout fisheries are important in the rivers and still more off the coast. Fishermen from Tönsberg, Tromsö, Hammerfest, Vardö, Vadsö, &c., work with the arctic fisheries, sealing, whaling, &c., from Greenland to Spitsbergen and Novaya Zemlya. A fishery board at Bergen administers the Norwegian fisheries. The annual value of the coast fisheries ranges from £1,000,000 to £1,500,000.
Mining.—Norway is not rich in minerals. Coal occurs only on Andö, an island in Vesteraalen. Silver is mined at Kongsberg; copper at Röros, Sulitelma, and Aamdal in Telemarken; iron at Klodeberg near Arendal and in the Dunderlandsdal (developed early in the 20th century). Granite is quarried near Fredrikstad, Fredrikshald and Sarpsborg, and exported as paving setts and kerbstones, mostly to Great Britain and Germany. Good marble is found near Fredrikshald, and also in the Salten and Ranen districts.
Manufacturing Industries.—The most important are works connected with the timber trade, foundries and engineering shops, spinning and weaving mills, brick and tile works, breweries, paper mills, tobacco factories, flour-mills, glass works, and potteries, nail works, shipbuilding yards, rope works, factories for preserved food (especially fish), margarine, matches, fish guano, boots, and hosiery, distilleries and tanneries. The chief industrial centres are Christiania, Bergen, Fredrikstad and Sarpsborg, Drammen, Skien and Porsgrund, Trondhjem, Fredrikshald and Stavanger. Large water-power is available in many districts. A powerful impulse was given to industrial enterprise by the non-renewal of the customs treaty with Sweden in 1897, which established a protective systerr against that country.
Shipping and Commerce.—The Norwegians, in proportion to their numbers, are the first nation in the world in the mercantile marine industry. Actually their mercantile marine is only exceeded by those of Great Britain, Germany and the United States. From 1850 to 1880 the tonnage increased from 28,000 to more than 1,500,000. The tonnage now exceeds the latter figure, but steam has greatly increased the carrying power. In 1880 Norwegian steam vessels had a tonnage of about 52,000; they now exceed 640,000 tons. The annual value of imports is about £16,500,000, and of exports about £10,000,000. The growth of both may be judged from periodic averages—
1851-1855. 1866-1870. 1886-1890. Imports £2,800,000 £5,600,000 £9,200,000 Exports 2,400,000 3,000,000 6,600,000
Great Britain and Germany are the countries principally trading with Norway. Great Britain takes about 40% (by value) of Norwegian exports, and sends about 26% of the total imports into Norway; Germany takes 14% of the exports, and sends 28% of the imports. The chief articles of export are timber, wooden wares and wood pulp, principally to Great Britain, and fish products, principally to Germany, Sweden and Spain. These make 65% of the exports—others of importance are paper, ships, ice, stone and nails. Of the imports about 58% by value are for consumption, 42% material for production. Among the first are cereals (principally from Russia), groceries (from Germany), and clothing (from Germany and Great Britain). Among the second are coal (chiefly from Great Britain), hides and skins, cotton and wool, oil and machinery, steamships, and metal goods (from Great Britain, Germany and Sweden).
Government.—Norway is an independent, constitutional and hereditary monarchy, the union with Sweden having been dissolved on the 7th of June 1905, after lasting 91 years. The constitution rests on the fundamental law (grundlov) promulgated at Eidsvold on the 17th of May 1814, and altered in detail at various times. The executive is vested in the king, who comes of age at eighteen. His authority is exercised through, and responsibility for his official acts rests with, a council of state consisting of a minister and councillors, who are the heads of finance, public accounts, church and education, defence, public works, agriculture, commerce, navigation and industry and foreign affairs. The king appoints these councillors and high officials generally in the state, church, army, navy, &c. He can issue provisional ordinances pending a meeting of parliament, can declare war (if a war of offence, only with the consent of parliament) and conclude peace, and has supreme command of the army and navy. The legislative body is the parliament (storthing), the members of which are elected directly by the people divided into electoral divisions, each returning one member. Until the election of 1906 the members were chosen by electors nominated by the voters. Elections take place every three years. The franchise is extended to every Norwegian male who has passed his twenty-fifth year, has resided five years in the country, and fulfils the legal conditions of citizenship. Under the same conditions, and if they or their husbands have paid taxes for the past year, the franchise is extended to women under a measure adopted by the Storthing in June 1907. Members of parliament must possess the franchise in their constituency, and must have resided ten years in the country; their age must not be less than thirty. The Storthing meets at Christiania, normally for two months in each year; it must receive royal assent to the prolongation of a session. After the opening of parliament the assembly divides itself into two sections, the upper (lagthing) consisting of one-quarter of the total number of members, and the lower (odelsthing) of the remainder. Every bill must be introduced in the Odelsthing; if passed there it is sent to the Lagthing, and if carried there also the royal assent gives it the force of law. If a measure is twice passed by the Odelsthing and rejected by the Lagthing, it is decided by a majority of two-thirds of the combined sections. The king has a veto, but if a measure once or twice vetoed is passed by three successive parliaments it becomes law ipso facto. This occurred when in 1899 the Norwegians insisted on removing the sign of union with Sweden from the flag of the mercantile marine. Members of parliament are paid 13s. 4d. a day during session and their travelling expenses. Parliament fixes taxation, and has control of the members of the council of state, who are not allowed to vote in either house, though they may speak.
Finance, &c.—The annual revenue and expenditure are each about 5½ millions sterling. Considerable sums, however, have been raised by loans, principally for railways. These amounted, between 1900 and 1906 (the financial year ending the 31st of March) to nearly £4,500,000. The principal sources of revenue are customs, railways, post office and telegraphs, the income tax (which is graduated and not levied on incomes below 1000 kroner or £55, 6s. 8d.), and excise. The principal items of expenditure are railways, defence (principally the army), the post office, interest on debt, the church and education, and justice. The Bank of Norway is a private joint-stock corporation, in which the state has large interests. It is governed by special acts of parliament, and its chief officials are publicly appointed. It alone has the right to issue notes, which are in wide circulation. The Mortgage Bank (Norges Hypothekbank) was established by the state to grant loans on real estate. The currency of Norway is based on a gold standard; but the monetary unit is the krone (crown), of 1s. 1⅓d. value, divided into 100 öre. The metric system is in use.
Army and Navy.—The army consists of the line, the militia or reserve (landværn), and the second reserve (landstorm). All capable men of twenty-two years of age and upwards are liable for conscription (except the clergy and pilots), and when called they serve 6 years in the line, 6 years with the reserve and 4 years with the second reserve. In war, men are liable to service from the 18th to the 50th year of age. Only the line can be sent out of the country. The men only meet for military training from 18 to 102 days in each year. The peace establishment of the line is 12,000 men, with 750 officers; its war footing 26,000, or more, but may not exceed 18,000 without the authority of parliament. Of enlisted troops there are only fortress garrisons, and the Christiania garrison of Norwegian Guards; The principal fortresses are Oscarsborg on Christiania Fjord, Agdenes (Trondhjem Fjord), Bergen, Tönsberg and Christiansand. A number of Norwegian forts along the S. Swedish frontier were dismantled under the convention with Sweden of 1905, when a neutral zone was established on either side of the frontier southward from 61° N. The navy consists of about 1200 officers and men on permanent service; but all seafaring men between twenty-two and thirty-eight are liable for maritime conscription, and are put through some preliminary training. The war vessels include four battleships of 3500 to 4000 tons each, and about 16 other vessels, besides a torpedo flotilla—intended for coast defence only. The chief naval station is at Karljohansværn (Horten).
Justice.—Civil cases are usually brought first before a commission of mediation (forligelseskommission), from which an appeal lies to the local inferior courts, which are also tribunals of first instance, and are worked by judges on circuit and assessors. There are three superior courts of appeal (overretter), at Christiania, Bergen and Trondhjem, and one supreme court (höiesteret). Criminal cases are tried either in jury courts (lagmandsret) or courts of assize (meddomsret). The first is for more serious offences; the second deals with minor offences and is a court of first instance. Military crimes are dealt with by a military judicial organization. Finally there is a high court of impeachment (rigsret), before which members of parliament, the government, &c., are tried for misdemeanours committed in their public capacity.
Local Government.—The country is divided into twenty counties (amter) (see population), the cities of Christiania and Bergen being included in these. Other towns are formed into communes, governed by representatives, from whom a council (formænd) is elected by themselves. Rural communes (herreder) are similarly administered, and their chairmen form a county council (amtsthing) for each county. At the head is the amtmand, the county governor. The electoral franchise for local council election is for men the same as the parliamentary franchise, and, like it, is extended in a limited degree to women.
Religion and Education.—The state religion, to which the king must conform, is Evangelical Lutheran. Only about 2.4% of the population are dissenters. All Christian sects except Jesuits are tolerated. The king nominates the clergy of the established church. Norway is divided into six bishoprics (stifter), Christiania, Hamar, Christiansand, Bergen, Trondhjem, Tromsö; and these into deaneries (provstier), with subdivisions into clerical districts (præstegjeld), parishes and sub-parishes. The clergy take a leading part in primary education, which, in spite of the difficulties arising in a sparsely populated country, reaches a high standard. Education is compulsory, the school-going age being from 6½ to 14 years in towns and 7 to 14 years in the country. About 94% of the children of school-going age attend the primary schools, which are administered by school boards in the municipalities and the counties. Teachers must belong to the established church. Their training colleges include one free public college in each diocese. The municipalities and counties bear the cost of primary education with a state grant. There are continuation schools, evening schools, &c., and for secondary education, communal middle schools, and state gymnasier. There is a state-aided university at Christiania.
Authorities.—See Norway (official publication for the Paris Exhibition) (Eng. trans., Christiania, 1900, dealing with the land and its inhabitants in every aspect, and giving Norwegian bibliographies for each subject); A. N. Kiær and others, Norges Land og Folk (Christiania, 1884 seq.); N. Rolfsen, Norge i det Nittende Aarhundrede (Christiania, 1900 seq.); Y. Nielsen, Reisehaandbog over Norge (10th ed., Christiania, 1903); various guidebooks in English; P. B. du Chaillu, The Land of the Midnight Sun (London, 1881); and The Land of the Long Night (London, 1900); C. F. Keary, Norway and the Norwegians (London, 1892); A. F. Mockler-Ferryman, In the Northman's Land (London, 1896); J. Bradshaw, Norway, its Fjords, Fields and Fosses (London, 1896); A. Chapman, Wild Norway (London, 1897); E. B. Kennedy, Thirty Seasons in Scandinavia (London, 1903); E. C. Oppenheim, New Climbs in Norway (London, 1898); W. C. Slingsby, Norway, The Northern Playground (on mountaineering) (Edinburgh, 1904); H. H. Reusch, Det Nordlige Norges Geologi (Christiania, 1892); T. Kjerulf, Udsigt over det sydlige Norges geologi (Christiania, 1879; a German translation was published at Bonn, 1880); W. C. Brögger, Die Silurischen Etagen 2 und 3 (Christiania, 1882); see also a series of memoirs on the eruptive rocks of the Christiania region in Videnskabsselskabets Skrifter (Christiania); A. E. Törnebohm, Grunddragen af det centrala Skandinaviensbergbyggnad, Kongl. Svenska Vetensk. Akad. Handl. vol. xxvii. No. 5 (1896); Jahrbuch des Norwegischen Meteorologischen Instituts (Christiania); H. Mohn, “ Klima Tabeller for Norge,” in Videnskabsselsk. Skrifter (1895 seq.); M. N. and A. Blytt, Norges Flora (Christiania, 1861-1877); C. Hartman, Handbok i Scandinaviens Flora (Stockholm, 1879); J. M. Norman, Norges Arktiske Flora (Christiania, 1894 seq.); Statistisk Aarbog for Kongeriget Norge (Christiania, annual); H. L. Brækstad, Constitution of the Kingdom of Norway (London, 1905); F. Nansen, Norway and the Union with Sweden, and Supplementary Chapter, separate (London, 1905). On the licensing system in Norway—Foreign Office Report, Misc. series, 279 (London, 1893); Board of Trade Rep. on Production and Consumption of Alcoholic Liquors (London, 1899); H. E. Berner, “Braendevinsbolagene i Norge,” in Nordisk Tidskrift (1891).
(O. J. R. H.)
History.
Early History.—Archaeological and geological researches have revealed a fishing and hunting population in Norway, possibly as far back as c. 6000 B.C. Until lately this aboriginal people, which was certainly non-Aryan, was held to be Lappish, but recent investigations seem to show that the Lapps only entered Norway about A.D. 900-1000, and that the original population was probably of Finnish race, though only distantly allied to the Ugro-Finns now inhabiting Finland. To them belong perhaps certain non-Aryan names for natural features of the country, such as Toten, Vefsen, Bukn.
The time of the immigration of a Teutonic element is far from certain. It did not extend N. beyond the Trondhjem district Teutonic immigration. until about the beginning of our era, but there can be little doubt that the immigrants' advance was extremely slow, and it is suggested, on the evidence of archaeology, that the Teutonic element entered S. Norway towards the end of the (Scandinavian) later Stone age, c. 1700 B.C. (see Scandinavian Civilization). But whatever were the stages of the process, the language of the older race was superseded by Teutonic, and those aborigines who were not incorporated (probably most often as slaves) were driven into the mountains or the islands that fringe the coast. In the highlands the “Finns” maintained some independence down to historical times. The old English poem Beowulf mentions a “Finnaland” which should perhaps be located in S. Norway in about the 6th century, and later on the ancient laws of this region forbid the practice of visiting the “Finns” to obtain knowledge of the future. But only in Finmark, which even in the 13th century stretched far into Sweden and included the Norwegian district of Tromsö, could the earlier inhabitants live their old life, and here they finally fell into the utmost want and misery. Their existence is mentioned as a thing of the past by a North Trondhjem writer in 1689.
The new Teutonic element of population seems to have flowed into Norway from two centres; one western, probably from Jutland, the other eastern, from the W. coast of Sweden. The western stream covered Agder, Rogaland and Hordaland (the modern districts of Christiansand and Söndre Bergenhus), and finally extended N. as far as Söndmöre, while the eastern stream flowed across Romerike and Hadeland through the Dales to the Trondhjem district, where it divided, one stream flowing down the W. coast till it met the western settlements, another penetrating N. into Haalogaland (which included the modern Nordland as well as Helgeland), and a third E. into the N. Swedish districts of Jämtland and Helsingland. The bodies of immigrants were no doubt more or less independent, and each was probably under a king. It is probable that the Horder, who gave their name to Hordaland and Hardanger, were a branch of the Harudes whom Ptolemy in the 2nd century mentions as living in Jutland, where their name remains in the present Hardesyssel. The Ryger, who gave their name to Rogaland, and the modern Ryfylke, are probably akin to the Rugii, an E. Germanic tribe at one time settled in N.E. Pomerania, where we have a reminiscence of their name in Rügenwalde. The first mention of any tribe settled in Norway is by Ptolemy, who speaks of the Chaidenoi or Heiner, inhabiting the W. of his island Scandia. The system of settlement in Norway appears to have been different from that adopted by the same race in other lands. In Denmark, for instance, a group of as many as twenty settlers held land more or less in common, but this system, which demanded that a considerable extent of land should be readily accessible, was not feasible in the greater part of Norway, and except in one or two flatter districts each farm was owned, or at least worked, by a single family.
When history first sheds a faint light over Norway we find each small district or “fylke” (Old Norse fylkir, from folk, army) settled under its own king, and about twenty-nine Early kingship. fylker in the country. At times a king would win an overlordship over the neighbouring tribes, but the character of the country hindered permanent assimilation. The king always possessed a hird, or company of warriors sworn to his service, and indeed royal birth and the possession of such a hird, and not land or subjects, were the essential attributes of a king. There was no law of primogeniture, and on the death of a king some of his heirs would take their share of the patrimony in valuables, gather a hird, and spend their lives in warlike expeditions (see Vikings), while one would settle down and become king of the fylke. There are indications that these conditions were fostered by a matriarchal system, and that it would often occur that a wandering king would marry the daughter of a fylkes-king and become his heir. Probably the king's power was only absolute over his own hird. He was certainly commander-in-chief and perhaps chief priest of the fylke, but the administrative power was chiefly in the hands of the herser and possibly of an earl. The position of earls is vague, but it is noticeable that both those of whom we hear in Harald Haarfager's time take the opposite side to their king. The herser (Old Norse hersir), of whom there were several in each fylke, united high birth with wealth and political power, and with the holder, the class of privileged hereditary landowners from which they sprang, formed an aristocracy of which there seems little trace in the other Scandinavian countries at this period. Its rise in Norway is perhaps due to the fact that the nature of the country, as well as the individualistic system of settlement, left more scope for inequalities of wealth than in Denmark or Sweden. Once a family had become wealthy enough to fit out Viking ships, it must have added wealth to wealth, besides enormously raising its prestige. The lands of almost all the most powerful families were on islands, whence it was easy to set forth on roving expeditions. The family property of the earls of Lade, for instance, whose representative in the latter half of the 9th century was the most powerful man of the district, was on the island of Nærö. These islands had been the refuge of the aborigines, and it is possible that, as A. Hansen has suggested, the rise of the aristocracy depends here, as elsewhere, on a subject population. Among the proper names of thralls in a poem in the Elder Edda are several which can only be explained on the hypothesis that they are Finnish, e.g. Klums, Lasmer, Drumba. Harald Haarfager's decree concerning “those who clear forests and burn salt, fishermen and hunters” probably refers to the Finns as a class apart. There can be no doubt that, in Haalogaland for instance, the aristocracy gained its wealth not only from the tribute extorted from the Finns in Finmark, but also from slave labour.
The eight Trondhjem fylker had a common Thing or assembly very early, but these districts were remote, while the wealthy western districts were too much cut off from each other to unite effectively, though here also a common Thing was early established. The first successful attempt at unification originated round Vestfold, the modern Jarlsberg and Laurvik Amt on the Christiania fjord. Here also there was a certain degree of union very early, and it is possible that national feeling was fostered by proximity to the Danish and Swedish kingdoms. The district was thickly populated, and a centre of commerce. Tradition made the royal family a branch of the great Yngling dynasty of Upsala, which claimed descent from the god Frey. Through several generations this family had extended its kingdom by marriage, conquest and inheritance, and by the end of the reign of Halfdan the Black, it included the greater part of Hamar and Oslo Stift, and the fylke of Sogn, the district round the modern Sognefjord.
Harald died in 933. Erik Blodöxe (Bloody-axe) only managed to rid himself of two rival over-kings, Olaf and Sigfred, his Haakon the Good. half-brothers, for on hearing of his father's death, another son, Haakon (q.v.), called the Good, who had been brought up at Æthelstan's court, came to Norway with a small force and succeeded in ejecting Erik (934), After Haakon's death in 961 at the battle of Fitje, where his long struggle against Erik's sons and their Danish allies terminated, these brothers, headed by Harald Graafeld (grey-cloak) became masters of the W. districts, though the ruling spirit appears to have been their mother Gunhild. Earl Sigurd of Lade ruled the N., and the S. was held by vassal kings whom Haakon had left undisturbed. By 969 the brothers had succeeded in ridding themselves of Sigurd and two other rivals, but the following year Harald Graafeld was lured to Denmark and treacherously killed at the instigation of Earl Haakon, son of Sigurd, who had allied himself with the Danish king Harald Gormssön. With the latter's support Earl Haakon won Norway, but threw off his yoke on defeating Ragnfred Erikssön at Tingenes in 972. The S.E. districts were, however, still held by Harald Grenske, whose father had been slain by the sons of Erik. Haakon ruled ably though tyrannically, and his prestige was greatly increased by his victory over the Jomsvikings, a band of pirates inhabiting the island of Wollin at the mouth of the Oder, who had collected a large fleet to attack Norway. The date of their defeat at Hjörungavaag, now Lidvaag, is uncertain. But finally the earl's disregard of the feelings of the most powerful “bonder,” or landed proprietors, worked them up to revolt, and, in 995, there landed in Norway Olaf, great-grandson of Harald Haarfager and son of the king Tryggve of the Vik whom Gudröd Eriksson had slain, and whose father Olaf had been slain by Erik Blodöxe.
The earl was treacherously killed by his thrall while in hiding, and Olaf entered unopposed upon his short and brilliant reign. Introduction of Christianity by Olaf. His great work was the enforced conversion to Christianity of Norway, Iceland and Greenland. In this undertaking both Olaf and his successor and namesake looked for help to England, whence they obtained a bishop and priests; hence it comes that the organization of the early church in Norway resembles that of England. No more than England did Norway escape the struggle between Church and State, but the hierarchical party in Norway only rose to power after the establishment of an archiepiscopal see at Trondhjem in 1152, after which the quarrel raged for over a century. Until the year 1100, when tithes were imposed, the priests depended for their livelihood on their dues, and Adam of Bremen informs us that this made them very avaricious.
In the year 1000 Olaf fell at the battle of Svolder off Rügen, fighting against the combined Danish and Swedish fleets. The Relations with Denmark. allies shared Norway between them, but the real power lay in the hands of Erik and Svein, sons of Earl Haakon. In 1015, when Erik was absent in England, another descendant of Harald Haarfager appeared, Olaf, the son of Harald Grenske, a great-grandson of Harald Haarfager (see Olaf II. Haraldssön). He defeated Svein at Nesje in 1016, which left him free to work towards a united and Christian Norway. For some years he was successful, but he strained the loyalty of his subjects too far, and on the appearance of Knut the Great in 1029 he fled to Russia. His death at the battle of Stiklestad on his return in 1030 was followed by a few years of Danish rule under Svein Knutssön, which rendered Olaf's memory sweet by contrast, and soon the name of St Olaf came to stand for internal union and freedom from external oppression. In 1035 his young son Magnus, afterwards called the Good, was summoned from Russia, and was readily accepted as king. A treaty was made with Hardeknut which provided that whichever king survived should inherit the other's crown. Hardeknut died in 1042, and Magnus became king of Denmark, but a nephew of Knut the Great, Svein Estridssön, entered into league with Harald Haardraade (see Harald III.), the half-brother of St Olaf, who had just returned from the East. As soon, however, as overtures were made to him by Magnus, he forsook the cause of Svein, and in 1046 agreed to become joint king of Norway with Magnus. The difficulties arising out of this situation were solved by Magnus's death in 1047.
Harald's attempts to win Denmark were vain, and in 1066 he set about a yet more formidable task in attacking England, End of Harald Haarfager's line. which ended with his death at Stamford Bridge in 1066. His son Olaf Kyrre (the Quiet) shared the kingdom with his brother Magnus until the latter's death in 1069, after which the country enjoyed a period of peace. A feature of this reign is the increasing importance of the towns, including Bergen, which was founded by Olaf. In 1093 Olaf was succeeded by his turbulent son Magnus Barfod (barefoot) and by Haakon, son of Magnus the Good. The latter died in 1095. Besides engaging in an unsuccessful war against the Swedish king Inge, in which he was defeated at Foxerne in 1101, Magnus undertook three warlike expeditions to the Scottish isles. It was on the last of these expeditions, in 1103, that he met his death. He was succeeded by his three sons, Eystein, Sigurd and Olaf. Olaf died young. Sigurd undertook a pilgrimage, from which he gained the name of Jorsalfar (traveller to Jerusalem). He won much booty from the Moors in Spain, from pirates in the Mediterranean, and finally at Sidon, which he and his ally Baldwin I. of Jerusalem took and sacked. Eystein died in 1122. Sigurd lived till 1130, but was subject to fits of insanity in his later years. He was the last undoubted representative of Harald Haarfager's race, for on his death his son Magnus was ousted by Harald Gille, or Gilchrist, who professed to be a natural son of Magnus Barfod.
Harald Gille was slain in 1136 by another pretender, and anarchy ruled during the reign of his sons Eystein, Inge and Disputed successions. Sigurd Mund. At last Inge's party attacked and killed first Sigurd (1155) and then Eystein (1157). Inge fell in a fight against Sigurd's son Haakon Herdebred in 1161, but a powerful baron, Erling, succeeded in getting his son Magnus made king, on the plea that the boy's maternal grandfather was King Sigurd Jorsalfar. Descent through females was not valid in succession to the throne, and to render his son's position more secure, Erling obtained the support of the Church. In 1164 the archbishop of Trondhjem crowned Magnus, demanding that the crown should be held as a fief of the Norwegian Church. Owing to such concessions the Church was gaining a paramount position, when a new pretender appeared. Sverre (O.N. Sverrir) claimed to be the son of Sigurd Mund, and was adopted as leader by a party known as the Birkebeiner or Birchlegs. He possessed military genius of a rare order, and in spite of help from Denmark, the support of the Church and of the majority of barons, Magnus was defeated time after time, till he met his death at the battle of Nordnes in 1184. The aristocracy could offer little further opposition. In joining hands with the Church against Sverre, the local chiefs had got out of touch with the small landowners, with whose support Sverre was able to build up a powerful monarchy. Sverre's most dangerous opponent was the Church, which offered the most strenuous resistance to his efforts to cut down its prerogatives. The archbishop found support in Denmark, whence he laid his whole see under an interdict, but Sverre's counter-claim of his own divine right as king had much more influence in Norway.
Sverre died in 1202, his last years harassed by the rise of the Baglers, or “crozier-men,” with a new claimant at their Magnus. head. His son Haakon III. died two years later, perhaps of poison, but the Birkebeiner party in 1217 succeeded in placing Haakon's son and namesake on the throne (see Haakon IV.). In 1240 the last of the rival claimants fell, and the country began to regain prosperity. The acquisition of Iceland was at length realized. Haakon's death occurred after the battle of Largs in the Orkneys in 1263. The war with Scotland was soon terminated by his son Magnus, who surrendered the Hebrides and the Isle of Man at the treaty of Perth in 1268. Magnus saw the worthlessness of a doubtful suzerainty over islands which had lost their value to Norway since the decay of Viking enterprise. He gained his title of Law-Mender from the revision of the laws, which had remained very much as in heathen days, and which were still different for the four different districts. By 1274 Magnus had secured the acceptance of a revised compilation of the older law-books. The new code repealed all the old wergild laws, and provided that the major part of the fine for manslaughter should be paid to the victim's heir, the remainder to the king. Henceforward the council comes more and more to be composed of the king's court officials, instead of a gathering of the lendermænd or barons of the district in which the king happened to be. During Magnus's reign we hear of a larger council, occasionally called palliment (parliament), which is summoned at the king's wish. The old landed aristocracy had lost its power so completely that even after Magnus's death in 1280 it was unable to reinstate itself during the minority of his son Erik.
Erik was succeeded in 1299 by his brother Haakon V., who in 1308 felt himself strong enough to abolish the dignity of the Paralysis of the aristocracy. lendermænd. This paralysis of the aristocracy is no doubt partly to be ascribed to the civil wars, but in part also to the gradual impoverishment of the country, which told especially upon this class. Russia had long eclipsed Norway as the centre of the fur trade, and other industries must have suffered, not only from the civil wars, but also from the supremacy of the Hanseatic towns, which dominated the North, and could dictate their own terms. In earlier times the aristocratic families had owed their wealth to three main sources: commerce, Viking expeditions and slave labour. Trade had been a favourite means of enrichment among the aristocracy up to the middle of the 13th century, but now it was almost monopolized by Germans, and Viking enterprise was a thing of the past. The third source of wealth had also failed, for it is clear from the laws of Magnus that the class of thralls had practically disappeared. This must have greatly contributed to shatter the power of the class which had once been the chief factor in the government of Norway.
Haakon's daughter Ingeborg had married Duke Erik of Sweden, and on Haakon's death in 1319 their three-year-old son Magnus succeeded to the Norwegian and Swedish thrones, the two countries entering into a union which was not definitely broken till 1371. It was during this reign that Norway was ravaged by the Black Death. In 1343 Magnus handed over the greater part of Norway to his son Haakon VI., who married Margrete, daughter of King Valdemar III. of Denmark. Their young son Olaf V., already king of Denmark, succeeded to his father's throne on Haakon's death in 1380, but died in 1387, leaving the royal line extinct, and the nearest successor to the throne the hostile King Albrecht of Sweden, of the Mecklenburg family. The difficulty was met by filling the throne by election—an Union of Norwegian, Swedish, and Danish thrones. innovation in Norway, though it was the custom in Sweden and Denmark. The choice fell on King Haakon's widow Margrete, but a couple of years later, chiefly in order to gain German support in a coming struggle with the Mecklenburgers, the Norwegians elected as king the young Erik of Pomerania, great-nephew of the queen, who henceforth acted as regent. Erik had claims on the Swedish and Danish thrones, and in 1397, at Kalmar, he was solemnly crowned king over the three countries, which entered into a union “never to be dissolved.”
Reigns of the Kings of Norway. Harald (I.) Haarfager 972-930 (d. 933) Erik Blodöxe 930-934 Haakon (I.) den Gode 935-961 Harald (II.) Graafeld 961-970 (Earl Haakon of Lade 970-995) Olaf (I.) Tryggvessön 995-1000 (Earls Erik and Haakon 1000-1016) Saint Olaf (II.) 1016-1029 (k. 1030) Svein, son of Knut the Great 1030-1035 Magnus (I.) den Gode 1035-1047 Harald (III.) Haardraade 1046-1066 Olaf (III.) Kyrre ${\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\ \end{matrix}}\right\}\,}}$ 1066-1093 Magnus (II.) 1066-1069 Magnus (III.) Barfod 1093-1103 Eystein (I.) ${\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\\\ \ \end{matrix}}\right\}\,}}$ 1103-1122 Sigurd (I.) Jorsalfar 1103-1130 Olaf (IV.) 1103-1116 Magnus (IV.) ${\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\ \end{matrix}}\right\}\,}}$ 1130-1135 Harald Gille 1130-1136 Sigurd (II.) Mund ${\displaystyle \scriptstyle {\left.{\begin{matrix}\ \\\\\ \ \end{matrix}}\right\}\,}}$ 1136-1155 Eystein (II.) 1136-1157 Inge 1136-1161 Haakon (II.) Herdebred 1161-1162 Magnus (V.) 1162-1184 Sverre 1184-1202 Haakon (III.) 1202-1204 Haakon (IV.) den gamle 1217-1263 Magnus (VI.) 1263-1280 Erik 1280-1299 Haakon (V.) 1299-1319 Magnus (VII.) 1319-1343 Haakon (VI.) 1343-1380 Olaf (V.) 1381-1387 Margrete 1387-1389 Erik of Pomerania 1389-
Authorities.—P. A. Munch, Det norske Folks Historie indtst 1397 (1852-1863); J. E. Sars, Udsigt over den norske Historie, Deel i.-ii. (1873-1877); R. Keyser, Norges Stats- og Retsforfatning (1867), and Den norske kirke undier Katholicismen (1856); A. Taranger, Den Angelsaksiske kirkes Indflydelse paa den norske (1891); A. C. Bang, Staat und Kirche in Norwegen bis zum Schlusse des 13ten Jahrhunderts (Munich, 1875); A. M. Hansen, Landnam i Norge (1904); A. Bugge, Studier over de norske Byers selvstyre og handel för Hanseaternes tid (1899); F. Bruns, Die Lübecker Bergenfahrer und ihre Chronistik (Berlin, 1900); articles by G. Storm, Y. Nielsen, E. Hertzberg and
others in the Historisk Tidskrift (Christiania) and other periodicals; also the articles by K. v. Armira, O. Bremer, K. Kaalund and V. Gudmundsson in Pauls Grundriss der germanischen Philologie (vol. iii., Strassburg, 1900). The above works are published in Christiania except where otherwise stated. In English, there is a history of Norway by H. H. Boyesen in the Story of the Nations series (London, 1900), and there are historical notes in G. Vigfússon and F. Y. Powell's Corpus poéticum Boreale (Oxford, 1883). The most important original sources are: Snorre Sturlasson's Heimskringla, or Lives of the Kings of Norway (up to 1177), of which there is an English translation by W. Morris and E. Magnússon, with a valuable index volume compiled by the latter, in the Saga Library, vols. iii.-vi. (London, 1893-1905). The original Icelandic text is edited by F. Jónsson (Copenhagen, 1893-1901). For a critical investigation into the sources of Snorri and the contemporary historians, see G. Storm, Snorre Sturlasson's Historieskrivning (Copenhagen, 1873, with map of ancient Norway), and F. Jónsson, Den oldnorske og oldislandske Litteraturs Historie (Bd. ii. Del. ii., Copenhagen, 1901). Of later sagas, Sverre's Saga (Fornmanna Sögur, vol. viii., Copenhagen) is translated by J. Sephton, Northern Library (vol. iv., London, 1899), and Haakon's Saga is given with a translation by G. W. Dasent in vols. ii. (text) and iv. (translation) of the Chronicles and Memorials of Great Britain and Ireland (London, 1894). Other important sources are: Diplomatarium Norvegicum, ed. C. Unger, Christiania, and Norges Gamle Love indtil 1397, ed. R. Keyser and P. A. Munch (5 vols., Christiania, 1846-1895).
(B. S. P.)
1397-1814.—The history of Norway from 1397 down to the union with Sweden in 1814 falls naturally into four divisions. First, in 1450, the triple bond gave place to a union in which Norway became more firmly joined to Denmark. Next, in 1536, as the result of the Reformation, Norway sank almost to the level of a province. After 1660 she gained something in status from the establishment of autocracy in Denmark, and at the close of the period she became a constitutional kingdom on a footing of approximate equality with Sweden. But for the convulsions to which some of these changes gave rise, Norway possesses during this period but little history of her own, and she sank from her former position as a considerable and independent nation. The kings dwelt outside her borders, her fleet and army decayed, and her language gradually 15th century. gave place to Danish. Germans plundered her coasts and monopolized her commerce, and after 1450 Danes began to appropriate the higher posts in her administration.
When in 1448 Karl Knutsson was chosen king by the Swedes, and Christian of Oldenburg by the Danes, it was by force that Norway fell to the latter. On the 24th of November 1449 the Norwegians protested against Christian's assumption of sovereignty over them, and against separation from the Swedes. Next year, however, the Swedes assented to the separation. Christian I. (1450-1481) gave estates and offices in Norway to his Danish subjects and raised money by pawning her ancient possessions, the Orkneys and Shetland islands, to the king of Scotland. His son Hans (1482-1513) purchased the obedience of the Norwegian nobles by concessions to their power. The imposing union continued in name, but the weakness of the nation and its government was strikingly illustrated when the Germans in Bergen besieged a monastery in which their enemy Olaf Nilsson, a high official, had taken refuge.
After the downfall of Christian II. (1513-1524) the position of Norway in relation to Denmark was changed for the worse. 16th century. She was ruled for a century and a quarter by Danish century officials; the churches and monasteries of Norway were sacked by Danes, and Danes were installed as pastors under the Lutheran system, which the Norwegians were compelled to accept in 1539. Soon Norway was dragged by Denmark into the so-called Seven Years' War of the North (1563-70). However, the power of the Hanse League in Bergen was broken. The rule of the Oldenburg dynasty proved neglectful rather than tyrannical, and under it the mass of the peasants was not flagrantly oppressed. Christian IV. (1588-1648), who founded Christiania, may almost be said to have discovered Norway anew. He reformed its government and strove to develop its resources, but his policy involved Norway in the loss 17th century. of the provinces of Jemtland and Herjedalen, which were ceded to the Swedes by the peace of Brömsebro (1645). The Danish war of revenge against Carl X. of Sweden resulted in further territorial loss by Norway. By the peace of Roskilde (1658) she was compelled to renounce the counties of Trondhjem and Baahus, and although the former was restored by the peace of Copenhagen, two years later, her population fell below half a million. The Swedes had now acquired the rich provinces in the south and south-west of the Scandinavian peninsula, and their ambition to extend their frontiers to the North Sea became more pronounced and more possible of accomplishment. From the middle of the 17th century, however, the Dutch and English made their influence felt, and the political status of Norway could no longer be regarded as a purely Scandinavian affair. The establishment of hereditary autocracy in Denmark by Frederick III. in 1660 conferred many benefits upon Norway. Personal liberty perhaps suffered, but the Norwegian peasant remained a freeman while his counterpart in Denmark was a serf. Norwegian law was revised and codified under Christian V. (1670-1699), who was well served by the Norwegians in his attempt to regain the lost provinces.
Under the sons of these monarchs, Frederick IV. and Carl XII., Norway was once more compelled to pay for Danish 18th century. aggression. Her shipping was destroyed, and in 1716, when driven from continental Europe, the Swedish hosts fell upon her. Two years later, however, the death of Carl XII. at the border fortress of Frederikshald averted the danger. During this war Peter Tordenskjold, the greatest among a long series of Norwegian heroes who served in the Danish fleet, won undying fame. Before the close of the 18th century something had been done towards dispelling the intellectual darkness. Holberg, though he flourished outside Norway, was at least born there, and by stemming the tide of German influence he made the future of Norwegian literature possible. At the close of the century Hans Nielson Hauge, the Wesley of Norway, appeared, while the growth of the timber trade with England gave rise to a great increase in wealth and population. In a century and a half the number of the Norwegian people was doubled, so that by 1814 Norway comprised some 900,000 souls. In 1788 the oppressive law that grain should be imported into Norway only from Denmark was repealed, and thanks to Danish policy Norway actually drew financial profit from the wars of the French Revolution.
The Norwegian national movement was to render a decade at the beginning of the 19th century more memorable in Norwegian Beginning of Norwegian national movement. history than any century which had passed since the Calmar Union. In 1800 the Danish government committed the Norwegians to the second Armed Neutrality, and therefore to a share in the battle of Copenhagen, by which it was broken up. It was not until 1807, however, that Norway was fully involved in the Napoleonic wars. Then, after the bombardment of Copenhagen, she was compelled by Danish policy to embrace the cause of Napoleon against both England and Sweden. Commerce was annihilated, and the supply of food failed. The national distress brought into the forefront of politics national leaders, among whom Count Hermann Jasper von Wedel-Jarlsberg was the most conspicuous. As yet, however, patriotism went no further than a demand for an administration distinct from that of Denmark, which was conceded in 1807, and for a university nearer home than Copenhagen. In 1811 the government assented to the foundation of the university of Christiania. (W. F. R.)
The union was more fully defined by the “Act of Union,” which was accepted by the national assemblies of both countries in the following year. In the preamble to the act it is clearly stated that the union between the two peoples was accomplished “not by force of arms, but by free conviction,” and the Swedish foreign minister declared to the European Powers, on behalf of Sweden, that the treaty of Kiel had been abandoned, and that it was not to this treaty, but to the confidence of the Norwegian people in the Swedish, that the latter owed the union with Norway. The constitution framed at Eidsvold was retained, and formed the Grundlov, or fundamental law of the kingdom. The union thus concluded between the two countries was really an offensive and defensive alliance under a common king, each country retaining its own government, parliament, army, navy and customs.
In Sweden the people received only an imperfect and erroneous insight into the nature of the union, and for a long time believed it to be an achievement of the Swedish arms. They had hoped to make Norway a province of Sweden, and now they had entered into a union in which both countries were equally independent. During the first fifteen years the king was represented in Norway by a Swedish Viceroy, while the government was, of course, composed only of Norwegians. Count Wedel Jarlsberg was the first to be entrusted with the important office of head of the Norwegian government, while several of Prince Christian Frederick's councillors of state were retained, or replaced by others holding their political views. The Swedish Count von Essen was appointed the first viceroy of Norway, and was succeeded two years afterwards by his countryman Count von Mörner, over both of whom Count Wedel exercised considerable influence.
In 1822 Count Wedel Jarlsberg retired from the government. He had become unpopular through his financial policy, and Royal proposals for constitutional revision. was also at issue with the king on vital matters. In 1821 he had been impeached before the Rigsret, the supreme court of the realm, for having caused the state considerable losses. Jonas Collett(1772-1851) was appointed as his successor to the post of minister of finance. The king had by this time apparently abandoned his plan of a coup d'état, for in the following August he submitted to the Storthing several proposals for fundamental changes in the constitution, all of which aimed at removing all that was at variance with a monarchical form of government. The changes, in fact, were the same as he had suggested in his circular note to the Powers, and which he knew would be hailed with approval by his Swedish subjects. When the Storthing met again in 1824 the royal proposals for the constitutional changes came on for discussion. The Storthing unanimously rejected not only the king's proposals, but also several others by private members for changes in the constitution. The king submitted his proposals again in the following session of the Storthing, and again later on, but they were always unanimously rejected. In 1830 they were discussed for the last time, with the same result. The king's insistence was viewed by the people as a sign of absolutist tendencies, and naturally excited fresh alarm. In the eyes of the people the members of the opposition in the Storthing were the true champions of the rights and the independence which they had gained in 1814.
By the July Revolution of 1830 the political situation in Europe became completely changed, and the lessons derived Increased political power of the peasantry. from that great movement reached also to Norway. The representatives of the peasantry, for whom the constitution had paved the way to become the ruling element in political life, were also beginning to distinguish themselves in the national assembly, where they now had taken up an independent position against the representatives of the official classes, who in 1814 and afterwards had played the leading and most influential part in politics. This party was now under the leadership of the able and gifted Ole Ueland, who remained a member of every Storthing from 1833 to 1869. The Storthing of 1833 was the first of the so-called “peasant Storthings.” Hitherto the peasantry had never been represented by more than twenty members, but the elections in 1833 brought their number up to forty-five, nearly half of the total representation. The attention of this new party was especially directed to the finances of the country, in the administration of which they demanded the strictest economy. They often went too far in their zeal, and thereby incurred considerable ridicule.
About this time the peasant party found a champion in the youthful poet Henrik Wergeland, who soon became one of the Wergeland opposed by Welhaven. leaders of the “Young Norway” party. He was a republican in politics, and the most zealous upholder of the national independence of Norway and of her full equality with Sweden in the union. A strong opposition to Wergeland and the peasant party was formed by the upper classes under the leadership of another rising poet and writer, Johan Sebastian Welhaven, and other talented men, who wished to retain the literary and linguistic relationship with Denmark, while Wergeland and his party wished to make the separation from Denmark as complete as possible, and in every way to encourage the growth of the national characteristics and feeling among the people. He devoted much of his time, by writing and other means, to promote the education of the people; but although he was most popular with the working and poorer classes, he was not able to form any political party around him, and at the time of his death he stood almost isolated. He died in 1845, and his opponents became now the leaders in the field of literature, and carried on the work of national reconstruction in a more restrained and quiet manner. The peasant party still continued to exist, but restricted itself principally to the assertion of local interests and the maintenance of strict economy in finance.
The violent agitation that began in 1830 died away. The tension between the king and the legislature, however, still continued, and reached its height during the session of 1836, when all the royal proposals for changes in the constitution were laid aside, without even passing through committee, and when various other steps towards upholding the independence of the country were taken. The king, in his displeasure, decided to dissolve the Storthing; but before it dispersed it proceeded to impeach Lövenskiold, one of the ministers, before the supreme court of the realm, for having advised the king to dissolve the Storthing. He was eventually sentenced to pay a fine of 10,000 kroner (about £550), but he retained his post. Collett, another minister who had greatly displeased the king by his conduct, was dismissed; but unity in the government was brought about by the appointment of Count Wedel Jarlsberg as viceroy of Norway. From this time the relations between the king and the Norwegian people began to improve, whereas in Sweden he was, in his later years, not a little disliked.
When the king's anger had subsided, he summoned the Storthing to an extraordinary session, during which several important The national flag question. bills were passed. Towards the close of the session an address to the king was agreed to, in which the Storthing urged that steps should be taken to place Norway in political respects upon an equal footing with Sweden, especially in the conduct of diplomatic affairs with foreign countries. The same address contained a petition for the use of the national or merchant flag in all waters. According to the constitution, Norway was to have her own merchant flag, and in 1821 the Storthing had passed a resolution that the flag should be scarlet, divided into four by a blue cross with white borders. The king, however, refused his sanction to the resolution, but gave permission to use the flag in waters nearer home; but beyond Cape Finisterre the naval flag, which was really the Swedish flag, with a white cross on a red ground in the upper square, must be carried. In reply to the Storthing's address the king in 1838 conceded the right to all merchant ships to carry the national flag in all waters. This was hailed with great rejoicings all over the country; but the question of the national flag for general use had yet to be settled. With regard to the question raised in the address of the Storthing about the conduct of diplomatic affairs, and other matters concerning the equality of Norway in the union, the king in 1839 appointed a committee of four Norwegians and four Swedes, who were to consider and report upon the questions thus raised.
During the sitting of this first “Union Committee” its powers were extended to consider a comprehensive revision of the Act Death of King Carl Johan; succeeded by Oscar I. of Union, with the limitation that the fundamental conditions of the union must in no way be interfered with. But before the committee had finished their report the king died (March 8th 1844), and was succeeded by his son Oscar I. According to the constitution the Norwegian kings must be crowned in Throndhjem cathedral, but the bishop of Throndhjem was in doubt whether the queen, who was a Roman Catholic, could be crowned, and the king decided to forego the coronation both of himself and his queen. The new king soon showed his desire to meet the wishes of the Norwegian people. Thus he decided that in all documents concerning the internal government of the country Norway should stand first where reference was made to the king as sovereign of the two kingdoms. After having received the report of the committee concerning the flag question, he resolved (June 20th, 1844) that Norway and Sweden should each carry its own national flag as the naval flag, with the mark of union in the upper corner; and it was also decided that the merchant flag of the two kingdoms should bear the same mark of union, and that only ships sailing under these flags could claim the protection of the state.
The financial and material condition of the country had now considerably improved, and King Oscar's reign was marked by the carrying out of important legislative work and reforms, especially in local government. New roads were planned and built all over the country, the first railway was built, steamship routes along the coast were established, lighthouses were erected and trade and shipping made great progress. The king's reign was not disturbed by any serious conflicts between the two countries. No change took place in the ministry under the presidency of the Viceroy Lövenskiold upon King Oscar's accession to the throne, but on the death or retirement of some of its members the vacant places were filled by younger and talented men, among whom was Fredrik Stang, who in 1845 took over the newly established ministry of the interior. During the Schleswig-Holstein rebellion (1848-1850) and the Crimean War King Oscar succeeded in maintaining the neutrality of Norway and Sweden, by which Norwegian shipping especially benefited. The abolition of the English navigation acts in 1850 was of great importance to Norway, and opened up a great future for its merchant fleet.
In 1826 a treaty had been concluded with Russia, by which the frontier between that country and the adjoining strip of Relations with Russia. Norwegian territory in the Polar region was definitely delimited; but in spite of this treaty Russia in 1851 demanded that the Russian Lapps on the Norwegian frontier should have the right to fish on the Norwegian coast, and have a portion of the coast on the Varanger fjord allotted to them to settle upon. The Norwegian government refused to accede to the Russian demands, and serious complications might have ensued if the attention of Russia had not been turned in another direction. While his father had looked to Russia for support, King Oscar was more inclined to secure western powers as his allies, and during the Crimean War he concluded a treaty with England and France, according to which these countries promised their assistance in the event of any fresh attempts at encroachment on Norwegian or Swedish territory by Russia. In consequence of this treaty the relations between Norway and Sweden and Russia became somewhat strained; but after the peace of Paris in 1856, and the accession of Alexander II., whose government was in favour of a peaceful policy, the Russian ambassador at Stockholm succeeded in bringing about more friendly relations.
Owing to the king's ill-health, his son, the crown prince Carl, was appointed regent in 1857, and two years later, when King Oscar died, he succeeded to the thrones of the two countries as Carl XV. He was a gifted, genial and noble personality, and Death of Oscar I.; accession of Carl XV. desired to inaugurate his reign by giving the Norwegians a proof of his willingness to acknowledge the claims of Norway, but he did not live to see his wishes in this respect carried out. According to the constitution, the king had the power to appoint a viceroy for Norway, who might be either a Norwegian or Swede. Since 1829 no Swede had held the post, and since 1859 no appointment of a viceroy had been made. But the paragraph in the constitution still existed, and the Norwegians naturally wished to have this stamp of “provinciality” obliterated. A proposal for the Question of Norwegian viceroy. abolishment of the office of viceroy was laid before the Storthing in 1859, and passed by it. The king, whose sympathies on this question were known, had been appealed to, and had privately promised that he would sanction the proposed change in the constitution; but as soon as the resolution of the Storthing became known in Sweden, a violent outcry arose both in the Swedish press and the Swedish estates. Under the pressure that was brought to bear upon the king in Sweden, he eventually refused to sanction the resolution of the Storthing; but he added that he shared the views of his Norwegian counsellors, and would, when “the convenient moment” came, himself propose the abolition of the office of viceroy.
In the following year the Swedish government again pressed the demands of the Swedish estates for a revision of the Act of Union, Swedish proposals for revision of Act of Union. which this time included the establishment of a union or common parliament for the two countries, on the basis that, according to the population, there should be two Swedish members to every Norwegian. The proposal was sent to the Norwegian government, which did not seem at all disposed to entertain it; but some dissensions arose with regard to the form in which its reply was to be laid before the king. The more obstinate members of the ministry resigned, and others, of a more pliable nature, were appointed under the presidency of Fredrik Stang, who had already been minister of the interior from 1845 to 1856. The reconstructed government was, however, in accord with the retiring one, that no proposal for the revision of the Act of Union could then be entertained. The king, however, advocated the desirability of a revision, but insisted that this would have to be based upon the full equality of both countries. In 1863 the Storthing assented to the appointment by the king of a Union committee, the second time that such a committee had been called upon to consider this vexatious question. It was not until 1867 that its report was made public, but it could not come on for discussion in the Storthing till it met again in 1871. During this period the differences between the two countries were somewhat thrust into the background by the Danish complications in 1863-1864, which threatened to draw the two kingdoms into war. King Carl was himself in favour of a defensive alliance with Denmark, but the Norwegian Storthing would only consent to this if an alliance could also be effected with at least one of the western powers.
In 1869 the Storthing passed a resolution by which its sessions were made annual instead of triennial according to the constitution of 1814. The first important question which the first yearly Storthing which met in 1871 had to consider was once more the proposed revision of the Act of Union. The Norwegians had persistently maintained that in any discussion on this question the basis for the negotiations should be (1) the full equality of the two kingdoms, and (2) no extension of the bonds of the union beyond the line originally defined in the act of 1815. However, the draft of the new act contained terms in which the supremacy of Sweden was presupposed and which introduced important extensions of the bonds of the union; and, strangely enough, the report of the Union committee was adopted by the new Stang ministry, and even supported by some of the most influential newspapers under the plausible garb of “Scandinavianism.” In these circumstances the “lawyers' party,” under the leadership of Johan Sverdrup, who was to play such a prominent part in Norwegian politics, and the “peasant party,” led by Sören Jaabœk, a gifted peasant proprietor, who was also destined to become a prominent figure in the political history of the country, Foundation of the Norwegian national party. formed an alliance, with the object of guarding against any encroachment upon the liberty and independence which the country had secured by the constitution of 1814. This was the foundation of the great national party, which became known as the “Venstre” (the left), and which before long became powerful enough to exert the most decisive influence upon the political affairs of the country. When, therefore, the proposed revision of the Act of Union eventually came before the Storthing in 1871, it was rejected by an overwhelming majority. The position which the government had taken up on this question helped to open the eyes of the Norwegians to some defects in the constitution, which had proved obstacles to the development and strengthening of the parliamentary system.
This was the political situation when King Carl died (18th September 1872). He was succeeded by his brother who ascended Death of Carl XV.; accession of Oscar II. the throne as Oscar II. In the following year he gave his sanction to the bill for the abolition of the office of viceroy, which the Storthing had again passed, and the president of the ministry was afterwards recognized as the prime minister and head of the government in Christiania. Fredrik Stang, who was the president of the ministry at the time, was the first to fill this office. In the same year Norway celebrated its existence for a thousand years as a kingdom, with great festivities.
In 1874 the government, in order to show the people that they to some extent were willing to meet their wishes with regard to Proposals by the Storthing for full popular control. the great question before the country, laid before the Storthing a royal proposition for the admittance of the ministers to the national assembly. But this was to be accompanied by certain other constitutional changes, such as giving the king the right of dissolving the Storthing at his pleasure and providing fixed pensions for ex-ministers, which was regarded as a guarantee against the majority of the assembly misusing its new power. The bill which the government brought in was unanimously rejected by the Storthing, the conservatives also voting against it, as they considered the guarantees insufficient. The same year, and again in 1877, the Storthing passed the bill, but in a somewhat different form from that of 1872. On both occasions the king refused his sanction.
The Storthing then resorted to the procedure provided by the constitution to carry out the people's will. In 1880 the bill was The king's veto. passed for the third time, and on this occasion by the overwhelming majority of 93 out of 113. Three Storthings after three successive elections had now carried the bill, and it was generally expected that the king and his government would at length comply with the wishes of the people, but the king on this occasion also refused his sanction, declaring at the same time that his right to the absolute veto was “above all doubt.” Johan Sverdrup, the leader of the liberal party and president of the Storthing, brought the question to a prompt issue by proposing to the Storthing that the bill, which had been passed three times, should be declared to be the law of the land without the king's sanction. This proposal was carried by a large majority on the 9th of June 1880, but the king and his ministers in reply declared that they would not recognize the validity of the resolution.
From this moment the struggle may be said to have centred itself upon the existence or non-existence of an absolute veto on Struggle between the king and the Storthing. the part of the crown. The king requested the faculty of law at the Christiania university to give its opinion on the question at issue, and with one dissentient the learned doctors upheld the king's right to the absolute veto in questions concerning amendments of the constitution, although they could not find that it was expressly stated in the fundamental law of the country. The ministry also advised the king to claim a veto in questions of supply, which still further increased the ill-feeling in the country against the government, and the conflict in consequence grew more and more violent.
In the midst of the struggle between the king and the Storthing, the prime minister, Fredrik Stang, resigned, and Christian Elections of 1882. August Selmer (1816-1889) became his successor; and this, together with the appointment of another member to the ministry, K. H. Schweigaard, plainly indicated that the conflict with the Storthing was to be continued. In June 1882 the king arrived in Christiania to dissolve the Storthing, and on this occasion delivered a speech from the throne, in which he openly censured the representatives of the people for their attitude in legislative work and on the question of the absolute veto, the speech creating considerable surprise throughout the country. Johan Sverdrup and Björnstjerne Björnson, the popular poet and dramatist, called upon the people to support the Storthing in upholding the resolution of the 9th of June, and to rouse themselves to a sense of their political rights. The elections resulted in a great victory for the liberal party, which returned stronger than ever to the Storthing, numbering 83 and the conservatives only 31. The ministry, however, showed no sign of yielding, and, when the new Storthing met in February 1883, the Odelsthing (the lower division of the Impeachment of ministers by the Storthing, 1883. national assembly) decided upon having the question finally settled by impeaching the whole of the ministry before the Rigsret or the supreme court of the realm. The jurisdiction of the Rigsret is limited to the trial of offences against the state, and there is no appeal against its decisions. The charges against the ministers were for having acted contrary to the interests of the country by advising the king to refuse his sanction—first, to the amendment of the law for admitting the ministers to the Storthing; secondly, to a bill involving a question of supply; and thirdly, to a bill by which the Storthing could appoint additional directors on the state railways.
The trial of the eleven ministers of the Selmer cabinet began in The ministry sentenced by the Rigsret. May 1883 and lasted over ten months. In the end the Rigsret sentenced the prime minister and seven of his ministers to be deprived of their offices, while three, who had either recommended the king to sanction the bill for admitting the ministers to the Storthing, or had entered the cabinet at a later date, were heavily fined. The excitement in the country rose to feverish anxiety. Rumours of all kinds were afloat, and it was generally believed that the king would attempt a coup d'état. Fortunately the king after some hesitation issued (11th March 1884) an order in council announcing that the judgment of the supreme court would be carried into effect, and Selmer was then called upon to resign his position as Acquiescence by the king. prime minister. King Oscar, however, in his declaration upheld the constitutional prerogative of the crown, which, he maintained, was not impaired by the judgment of the Rigsret. The following month the king, regardless of the large liberal majority in the Storthing, asked Schweigaard, one of the late ministers, whose punishment consisted in a fine, to form a ministry, and the so-called “April ministry” was then appointed, but sent in its resignation in the following month. Professor Broch, a former minister, next failed to form a ministry, and the king was at last compelled to appoint a ministry in accordance with the majority in the First Liberal ministry 1884. Storthing. In June 1884 Johan Sverdrup was asked to form one. He selected for his ministers leading men on the liberal side in the Storthing, and the first liberal ministry that Norway had was at length appointed. The Storthing, in order to satisfy the king, passed a new resolution admitting the ministers to the national assembly, and this received formal sanction.
During the following years a series of important reforms was carried through. Thus in 1887 the jury system in criminal matters was introduced into the country after violent opposition from the conservatives. A bill intended to give parishioners greater influence in church matters, and introduced by Jakob Sverdrup, the minister of education, and a nephew of the prime minister, met, however, with strong opposition, and was eventually rejected by the Storthing, the result being a break-up of the ministry and a disorganization of the liberal party. In June 1889 the Sverdrup ministry resigned, and a conservative one was formed by Emil Stang, the leader of the conservatives in the Storthing, and during the next two years the Storthing passed various useful measures; but the ministry was eventually wrecked on the rock of the great national question which about this time came to the front—that of Norway's share in the transaction of diplomatic affairs. At the time of the union in 1814 nothing had been settled as to how these were to be conducted, but in 1835 a resolution was issued, that when the The question of diplomatic representation. Swedish foreign minister was transacting diplomatic matters with the king which concerned both countries, or Norway only, the Norwegian minister of state in attendance upon the king at Stockholm should be present. This arrangement did not always prove satisfactory to the Norwegians, especially as the Swedish foreign minister could not be held responsible to the Norwegian government or parliament.
By a change in the Swedish constitution in 1885 the ministerial council, in which diplomatic matters are discussed, came to The Norwegian claim. consist of the Swedish foreign minister and two other members of the cabinet on behalf of Sweden, and of the Norwegian minister at Stockholm on behalf of Norway. The king, wishing to remedy this disparity, proposed that the composition of the council should be determined by an additional paragraph in the Act of Union. The representatives of the Norwegian government in Stockholm proposed that three members of the cabinet of each country should constitute the ministerial council. To this the Swedish government was willing to agree, but on the assumption that the minister of foreign affairs should continue to be a Swede as before, and this the Norwegians, of course, would not accept. At the king's instigation the negotiations with the Swedish government were resumed at the beginning of 1891, but the Swedish Riksdag rejected the proposals, while the Norwegian Storthing insisted upon “Norway's right, as an independent kingdom, to full equality in the union, and therewith her right to watch over her foreign affairs in a constitutional manner.” The Stang ministry then resigned, and a liberal ministry, with Steen, the recognized leader of the liberal party after Sverdrup's withdrawal from politics, as prime minister, was appointed.
The new ministry had placed the question of a separate minister of foreign affairs for Norway prominently in their programme, but Question of separate consular service. little progress was made during the next few years. Another and more important question for the country, as far as its shipping and commerce are concerned, now came to the front. The Storthing had in 1891 appointed a committee to inquire into the practicability of establishing a separate Norwegian consular service, and in 1892 the Storthing, acting upon the committee's report, determined to establish a consular service. The king, influenced by public opinion in Sweden, refused his sanction, and the Norwegian government in consequence sent in their resignation, whereupon a complete deadlock ensued. This was terminated by a compromise to the effect that the ministry would return to office on the understanding that the question was postponed by common consent. The following year the Storthing again passed a resolution calling upon the Norwegian government to proceed with the necessary measures for establishing the proposed consular service for Norway, but the king again refused to take any action in the matter. Upon this the liberal ministry resigned (May 1893), and the king appointed a conservative government, with Emil Stang as its chief. Thus matters went on till the end of 1894, when the triennial elections took place, with the result that the majority of the electors declared in favour of national independence on the great question then before the country. The ministry did not at once resign, but waited till the king arrived in Christiania to open the Storthing (January 1895). The king kept the country for over four months without a responsible government, during which time the crisis had become more acute than ever. A coalition ministry was at last formed, with Professor G. F. Hagerup as prime minister. A new committee, consisting of an equal number of Norwegians and Swedes, was appointed to consider the question of separate diplomatic representation; but after sitting for over two years the committee separated without being able to come to any agreement.
The elections in 1897 proved again a great victory for the liberal party, 79 liberals and 35 conservatives being returned, and in February 1898 the Hagerup ministry was replaced by a liberal, once more under the premiership of Steen. Soon afterwards the bill for the general adoption of the national or “pure” flag, as it was called, was carried for the third time, and became law without the king's sanction. In 1898 universal political suffrage for men was passed by a large majority, but the proposal to include women received the support of only 33 votes.
In January 1902, on the initiative of the Swedish foreign minister, another committee, consisting of an equal number of The crisis of 1902-1905. leading Norwegians and Swedes, was appointed by the king to investigate the consular question. The unanimous report of the committee was to the effect that “it was possible to appoint separate Norwegian consuls exclusively responsible to Norwegian authority and separate Swedish consuls exclusively responsible to Swedish authority.” The further negotiations between the two governments resulted in the so-called communiqué of the 24th of March 1903, which announced the conclusion of an agreement between the representatives of the two countries for the establishment of the separate consular service. The terms of the communiqué were submitted to a combined Norwegian and Swedish council of state on the 21st of December 1903, when they were unanimously agreed to and were signed by the king, who commissioned the Norwegian and the Swedish governments to proceed with the drafting of the laws and regulations for the separate consular services. In due course the Norwegian government submitted to the Swedish government their draft of the proposed laws and regulations, but no reply was forthcoming for several months. About this time the Swedish foreign minister, Mr Lagerheim, who had zealously worked for a friendly solution of the consular question, resigned, and in November the same year Boström, the Swedish prime minister, suddenly submitted to the Norwegian government a number of new conditions under which the Swedish government was prepared to agree to the establishment of separate consuls. This came as a surprise to the Norwegians in view of the fact that the basis for the establishment of separate consuls had already been agreed upon and confirmed by the king in December 1903. According to Boström's proposals the Norwegian consuls were to be placed under the control of the Swedish foreign minister, who was to have the power to remove any Norwegian consul. The Norwegians felt it would be beneath the dignity of a self-governing country to agree to the Swedish proposals, and that these new demands were nothing less than a breach of faith with regard to the terms of agreement arrived at two years before by both governments and approved and signed by the king. The Norwegian government would have been perfectly justified if, after this, they had withdrawn from the negotiations, but they did not wish to jeopardize the opportunity of arriving at a friendly settlement, and Hagerup, the Norwegian prime minister, proceeded to Stockholm to confer with Boström; but no satisfactory agreement could be arrived at. There was therefore nothing left but for the Norwegians to take matters into their own hands.
On the 8th of February 1905 Hagerup announced to the Norwegian Storthing that the negotiations had fallen through, and on the 17th the Storthing decided unanimously to refer the matter to a special committee. Owing to some difference of opinion between the members of his ministry, Hagerup resigned on the 1st of March and was succeeded by Christian Michelsen, who formed a ministry composed of members of both political parties. The special committee decided that a bill should be immediately submitted to the Storthing for the establishment of a Norwegian consular service and that the measure should come into force not later than the 1st of April 1906. An attempt was made by the Swedish crown prince, acting as Prince Regent during the king's illness, to enter into new negotiations with the Norwegian government, but the proposals were not favourably received in Norway. In April 1905 Boström resigned, which was considered to be a move on the part of Sweden to facilitate negotiations with Norway. The bill for the establishment of Norwegian consuls was passed by the Storthing without a dissentient voice on the 23rd of May, and it was generally expected that the king, who again had assumed the reins of government, would sanction the bill, but on the 27th of May, in spite of the earnest entreaties of his Norwegian ministers, the king formally refused to do so. The Norwegian Ministry immediately resigned, but the king informed the ministers that Declaration of Independence. he could not accept their resignation. They, however, declined to withdraw it. A few days afterwards the Norwegian government informed the Storthing of the king's refusal, whereupon the assembly unanimously agreed to refer the matter to the special committee. On the 7th of June the Storthing met to hear the final decision of the government. Michelsen, the prime minister, informed the Storthing that all the members of the government had resigned in consequence of the king's refusal to sanction the consular law, that the king had declined to accept the resignation, and that, as an alternative government could not be formed, the union with Sweden, based upon a king in common, was consequently dissolved. The president of the Storthing submitted a resolution that the resigning ministry should be authorized to exercise the authority vested in the king in accordance with the constitution of the country. The resolution was unanimously adopted.
King Oscar, on receiving the news of the action of the Norwegian Storthing, sent a telegraphic protest to the Norwegian prime minister and to the president of the Storthing. The Swedish government immediately decided to summon an extraordinary session of the Swedish Separation
from Sweden.
parliament for the 20th of June, when a special committee was appointed to consider what steps should be taken by Sweden. On the 25th of July the report of the committee was laid before the Riksdag, in which it was stated that Sweden could have no objection to enter into negotiations about the severance of the union, when a vote to that effect had been given by a newly-elected Storthing or by a national vote in the form of a referendum by the Norwegian people. The report was unanimously adopted by the Swedish Riksdag on the 27th of July, and on the following day the Norwegian Storthing decided that a general plebiscite should be taken on the 13th of August, when 368,211 voted in favour of the dissolution and only 184 against it. It was thereupon agreed that representatives of Norway and of Sweden should meet at Karlstad in Sweden on the 31st of August to discuss and arrange for the severance of the union. The negotiations lasted till the 23rd of September, though more than once they were on the point of being broken off. The agreement stipulated a neutral zone on both sides of the southern border between the two countries, the Norwegians undertaking to dismantle some fortifications within that zone. The agreement was to remain in force for ten years, and could be renewed for a similar period, unless one of the countries gave Election of
Haakon VII.
notice to the contrary. The Karlstad agreement was ratified by the Norwegian Storthing on the 9th of October and by the Swedish Riksdag on the 16th of the same month. On the 27th of October King Oscar issued a proclamation to the Norwegian Storthing, in which he relinquished the crown of Norway. The Norwegian government was thereupon authorized by the Storthing to negotiate with Prince Charles of Denmark and to arrange for a national vote as to whether or no the country would approve of his election for the Norwegian throne. The plebiscite resulted in 259,563 votes for his election and 69,264 against. On the 18th of November the Storthing unanimously elected Prince Charles as king of Norway, he taking the name of Haakon VII. On the 25th of November the king and his consort, Queen Maud, the youngest daughter of King Edward VII. of England, entered the Norwegian capital. Their coronation took place in the Trondhjem cathedral the following year.
In 1907 parliamentary suffrage was granted to women with the same limitation as in the municipal suffrage granted to them in 1901, viz. to all unmarried women over 25 years, who pay taxes on an income of 300 kroner (about £16) in the country districts and on 400 kroner (about £22) in the towns, as well as to all married women, whose husbands pay taxes on similar incomes. Norway was thus the first sovereign country in Europe where the parliamentary vote was granted to women. (H. L. B.)
Norwegian Literature
Early Norse literature is inextricably bound up with Icelandic literature. Iceland was colonized from Norway in the 9th century, and the colonists were drawn chiefly from the upper and cultured classes. They took with them their poetry and literary traditions. Old Norse literature is therefore dealt with under Iceland (q.v.). (See also Edda, Saga, Runes.)
The modern literature of Norway bears something of the same relation to that of Denmark that American literature bears to English. In each case the development and separation of a dependency have produced a desire on the part of persons speaking the mother-tongue for a literature that shall express the local emotions and conditions of the new nation. Two notable events led to the foundation of a separate Norwegian literature: the one was the creation of the university of Christiania in 1811, and the other was the separation of Norway from Denmark in 1814. Before this time Norwegian writers had been content, as a rule, to publish their works at Copenhagen. The first name on the annals of Danish literature, Peder Clausen, is that of a Norwegian; and if all Norse writers were removed from that roll, the list would be poorer by some of its most illustrious names, by Holberg, Tullin, Wessel, Treschow, Steffens and Hauch.
The first book printed in Norway was an almanac, brought out in Christiania in 1643 by a wandering printer named Tyge Nielsen, who brought his types from Copenhagen. But the first press set up definitely in Norway was that of Valentin Kuhn, brought over from Germany in 1650 by the theologian Christian Stephensen Bang (1580-1678) to help in the circulation of his numerous tracts. Bang's Christianiae Stads Beskrifuelse (1651), is the first book published in Norway. Christen Jensen (d. 1653) was a priest who collected a small glossary or glosebog of the local dialects, published in 1656. Gerhard Milzow (1629-1688), the author of a Presbyterologia Norwegica (1679), was also a Norse priest. The earliest Norwegian writer of any original merit was Dorthe Engelbrechtsdatter (1634-1716), afterwards the wife of the pastor Ambrosius Hardenbech. She is the author of several volumes of religious poetry which have enjoyed great popularity. The hymn-writer Johan Brunsmann (1637-1707), though a Norseman by birth, belongs by education and temper entirely to Denmark. Not so Petter Dass (1647-1708) (q.v.), the most original writer whom Norway produced and retained at home during the period of annexation. Another priest, Jonas Ramus (1649-1718), wrote Norriges Kongers Historie (History of the Norse Kings) in 1719, and Norriges Beskrivelse (1735). The celebrated missionary to Greenland, Hans Egede (1686-1758), wrote several works on his experiences in that country. Peder Hersleb (1689-1757) was the compiler of some popular treatises of Lutheran theology. Frederik Nannestad, bishop of Trondhjem (1693-1774), started a weekly gazette in 1760. The missionary Knud Leem (1697-1774) published a number of works on the Lapps of Finmark, one at least of which, his Beskrivelse over Finmarkens Lapper (1767), still possesses considerable interest. The famous Erik Pontoppidan (1698-1764) cannot be regarded as a Norwegian, for he did not leave Denmark until he was made bishop of Bergen, at the age of forty-nine. On the other hand the far more famous Baron Ludvig Holberg (1684-1754), belongs to Denmark by everything but birth, having left Norway in childhood.
A few Norsemen of the beginning of the 18th century distinguished themselves chiefly in science. Of these Johan Ernst Gunnerus (1718-1773), bishop of Trondhjem, was the first man who gave close attention to the Norwegian flora. He founded the Norwegian Royal Society of Sciences in 1760, with Gerhard Schöning (1722-1780) the historian and Hans Strom (1726-1797) the zoologist. Peder Christofer Stenersen (1723-1776), a writer of occasional verses, merely led the way for Christian Braumann Tullin (1728-1765), a lyrical poet of exquisite genius, who is claimed by Denmark but who must be mentioned here, because his poetry was not only mainly composed in Christiania, but breathes a local spirit. Danish literature between the great names of Evald and Baggesen presents us with hardly a single figure which is not that of a Norseman. The director of the Danish national theatre in 1771 was a Norwegian, Niels Krog Bredal (1733-1778), who was the first to write lyrical dramas in Danish. A Norwegian, Johan Nordahl Brun (1745-1816), was the principal tragedian of the time, in the French taste. It was a Norwegian, J. H. Wessel (1742-1785), who laughed this taste out of fashion. In 1772 the Norwegian poets were so strong in Copenhagen that they formed a Norske Selskab (Norwegian Society), which exercised a tyranny over contemporary letters which was only shaken when Baggesen appeared. Among the leading writers of this period are Claus Frimann (1746-1829), Peter Harboe Frimann (1752-1839), Claus Fasting (1746-1791), Johan Wibe (1748-1782), Edvard Storm (1749-1794), C. H. Pram (1756-1821), Jonas Rein (1760-1821), Jens Zetlitz (1761-1821), and Lyder Christian Sagen (1771-1850), all of whom, though Norwegians by birth, find their place in the annals of Danish literature. To these poets must be added the philosophers Niels Treschow (1751-1833) and Henrik Steffens (1773-1845), and in later times the poet Johannes Carsten Hauch (1790-1872).
The first form which Norwegian literature took as an independent thing was what was called “Syttendemai-Poesi,” or The “Trefoil.” poetry of the 17th of May, that being the day on which Norway obtained her independence and proclaimed her king. Three poets, called the “Trefoil,” came forward as the inaugurators of Norwegian thought in 1814. Of these Conrad Nicolai Schwach (1793-1860) was the least remarkable. Henrik Anker Bjerregaard (1792-1842), born in the same hamlet of Ringsaker as Schwach, had a much brighter and more varied talent. His Miscellaneous Poems, collected at Christiania in 1829, contain some charming studies from nature, and admirable patriotic songs. He brought out a tragedy of Magnus Barfods Sönner (Magnus Barefoot's Sons) and a lyrical drama, Fjeldeventyret (The Adventure in the Mountains) (1828). He became judge of the supreme court of the diocese of Christiania. The third member of the Trefoil, Mauritz Kristoffer Hansen (1794-1842), was a schoolmaster. His novels, of which Ottar de Bretagne (1819) was the earliest, were much esteemed in their day, and after his death were collected and edited (8 vols., 1855-1858), with a memoir by Schwach. Hansen's Poems, printed at Christiania in 1816, were among the earliest publications of a liberated Norway, but were preceded by a volume of Smaadigte (Short Poems) by all three poets, edited by Schwach in 1815, as a semi-political manifesto. These writers, of no great genius in themselves, did much by their industry and patriotism to form a basis for Norwegian literature.
The creator of Norwegian literature, however, was the poet Henrik Arnold Wergeland (1808-1845) (q.v.), a man of great Wergeland, Welhaven. genius and enthusiasm, who contrived within the limits of a life as short as Byron's to concentrate the labours of a dozen ordinary men of letters. He held views in most respects similar to those pronounced by Rousseau and Shelley. His obscurity and extravagance stood in the way of his teaching, and his only disciples in poetry were Sylvester Sivertson (1809-1847), a journalist of talent whose verses were collected in 1848, and Christian Monsen (1815-1852).
A far more wholesome and constructive influence was that of Johann Sebastian Cammermeyer Welhaven (1807-1873) (q.v.), who was first brought to the surface by the conservative reaction in 1830 against the extravagance of the radical party. A savage attack on Henrik Wergeland's Poetry, published in 1832, caused a great sensation, and produced an angry pamphlet in reply from the father, Nikolai Wergeland. The controversy became the main topic of the day, and in 1834 Welhaven pushed it into a wider arena by the publication of his beautiful cycle of satirical sonnets called Norges Dæmring (The Dawn of Norway), in which he preached a full conservative gospel. He was assisted in his controversy with Wergeland by Henrik Hermann Foss (1790-1853), author of Tidsnornerne (The Norns of the Age) (1835) and other verses.
Andreas Munch (1811-1884) took no part in the feud between Wergeland and Welhaven, but addicted himself to the study of Munch. Danish models independently of either. He published a series of poems and dramas, one of which latter, Kong Sverres Ungdom (1837), attracted some notice. His popularity commenced with the appearance of his Poems Old and New in 1848. His highest level as a poet was reached by his epic called Kongedatterens Brudefart (The Bridal Journey of the King's Daughter) (1861). Two of his historical dramas have enjoyed popularity greatly in excess of their merit; these are Solomon de Caus (1854) and Lord William Russell (1857).
A group of minor poetical writers may now be considered. Magnus Brostrup Landstad (1802-1880) was born on Maasö, an island in the Minor poets. vicinity of the North Cape, and, therefore, in higher latitudes than any other man of letters. He was a hymn-writer of merit, and he was the first to collect, in 1853, the Norske Folkeviser or Norwegian folk-songs. Landstad was ordered by the government to prepare an official national hymn-book, which was brought out in 1861; Peter Andreas Jensen (1812-1867) published volumes of lyrical poetry in 1838, 1849, 1855 and 1861, and two dramas. He was also the author of a novel, En Erindring (A Souvenir), in 1857. Aasmund Olafsen Vinje (1818-1870) was a peasant of remarkable talent, who was the principal leader of the movement known as the “maalstræv,” an effort to distinguish Norwegian from Danish literature by the adoption of a peasant dialect, or rather a new language arbitrarily formed on a collation of the various dialects. Vinje wrote a volume of lyrics, which he published in 1864, and a narrative poem, Storegut (Big Lad) (1866), entirely in this fictitious language, and he even went so far as to issue in it a newspaper, Dölen (The Dalesman), which appeared from 1858 to Vinje's death in 1870. In these efforts he was supported by Ivar Aasen and by Kristoffer Janson (b. 1841) the philologist, the author of an historical tragedy, Jon Arason (1867); several novels: Frau Bygdom (1865); Torgrim (1872); Fra Dansketidi (1875); Han og Ho (1878); and Austanfyre Sol og Vestanfyre Maane (East of the Sun and West of the Moon) (1879); besides a powerful but morbid drama in the ordinary language of Norway, En Kvindeskjebne (A Woman's Fate) (1879). In 1882 he left Norway for America as a Unitarian minister, and from this exile he sent home in 1885 what is perhaps the best of his books, The Saga of the Prairie. Superior to all the preceding in the quality of his lyrical writing was the bishop of Christiansand, Jörgen Moe (1813-1882). He is,
however, better known by his labours in comparative mythology, in conjunction with P. C. Asbjörnsen (see Asbjörnsen and Moe).
The names of the Norwegians Ibsen (q.v.) and Björnson (q.v.), in the two fields of the drama and the novel, stand out prominently in Modern novelists and dramatists. the European literature of the later 19th century; and two writers of novels who owe much to their example are Jonas Lie (q.v.), and Alexander Kielland (1849-1906). Nicolai Ramm Östgaard (1812-1872) to some extent preceded Björnson in his graceful romance En Fjeldbygd (A Mountain Parish), in 1852. Frithjof Foss (1830-1899), who wrote under the pseudonym of Israél Dehn, attracted notice by seven separate stories published between 1862 and 1864. Jacobine Camilla Collett (1813—1895), sister of the poet Wergeland, wrote Amtmandens Döttre (The Governor's Daughters) (1855), an excellent novel, and the first in Norwegian literature which attempted the truthful description of ordinary life. She was a pioneer in the movement for the emancipation of women in Norway. Anne Magdalene Thoresen (1819-1903), a Dane by birth, wrote a series of novels of peasant life in the manner of Björnson, of whom she was no unworthy pupil. One of her best novels is Signes Historie (1864). She also wrote some lyrical poetry and successful dramas. The principal historian of Norway is History, etc. Peter Andreas Munch (1810-1863), whose multifarious writings include a grammar of Old Norse (1847); a collection of Norwegian laws until the year 1387 (1846-1849); a study of Runic inscriptions (1848); a history and description of Norway during the middle ages (1849); and a history of the Norwegian people in 8 vols. (1852-1863); Jakob Aall (1773-1844) was associated with Munch in this work. Christian Berg (1775-1852) was another worker in the same field. Jakob Rudolf Keyser (1803-1864) printed and annotated the most important documents dealing with the medieval history of Norway. Carl Richard Unger (b. 1817) took part in the same work and edited Morkinskinna in 1867. His edition of the elder Edda (1867) forms a landmark in the study of Scandinavian antiquities. Oluf Rygh (1833-1899) contributed to the archaeological part of history. The modern language of Norway found an admirable grammarian in Jakob Olaus Lökke (1829-1881). A careful historian and ethnographer was Ludvig Kristensen Daa (1809-1877). Ludvig Daae (b. 1834) has written the history of Christiania, and has traced the chronicles of Norway during the Danish possession. Bernt Moe (1814-1850) was a careful biographer of the heroes of Eidsvold. Eilert Lund Sundt (1817-1875) published some very curious and valuable works on the condition of the poorer classes in Norway. Professor J. A. Friis (b. 1821) published the folk-lore of the Lapps in a series of valuable volumes. The German orientalist, Christian Lassen (1800-1876) was a Norwegian by birth. Lorentz Dietrichson (b. 1834) wrote voluminously both on Swedish and Norwegian, chiefly on Norwegian art and literature. In jurisprudence the principal Norwegian authorities are Anton Martin Schweigaard (1808-1870) and Frederik Stang (1808-1884). Peter Carl Lasson (1798-1873) and Ulrik Anton Motzfelt (1807-1865) were the lights of an earlier generation. In medical science, the great writer of the beginning of the 19th century was Michael Skjelderup (1769-1852), who was succeeded by Frederik Holst (1791-1871). Daniel Cornelius Danielsen (b. 1815) was a prominent dermatologist; but probably the most eminent of modern physiologists in Norway is Carl Wilhelm Boeck (1808-1875). The elder brother of the last-mentioned, Christian Peter Bianco Boeck (1798-1877), also demands recognition as a medical writer. Christopher Hansteen (1784-1873) was professor of mathematics at the university for nearly sixty years. Michael Sars (1805-1869) obtained a European reputation through his investigations in invertebrate zoology. He was assisted by his son Georg Ossian Sars (b. 1837). Baltazar Matthias Keilhau (1797-1858) and Theodor Kjerulf (1825-1888) have been the leading Norwegian geologists. Mathias Numsen Blytt (1789-1862) represents botany. His Norges Flora, part of which was published in 1861, was left incomplete at his death. Niels Henrik Abel (1802-1829) (q.v.) was a mathematician of extraordinary promise; Ole Jakob Broch (1818-1889) must be mentioned in the same connexion. Among theological writers may be mentioned Hans Nielsen Hauge (1771-1824), author of the sect which bears his name; Svend Borchman Hersleb (1784-1836); Stener Johannes Stenersen (1789-1835); Wilhelm Andreas Wexels (1797-1866); a writer of extraordinary popularity; and Carl Paul Caspari (1814-1892), a German of Jewish birth, who adopted Christianity and became professor of theology in the university of Christiania.
The political crisis of 1884-1885, which produced so remarkable an effect upon the material and social life of Norway, was not The new movement. without its influence upon literature. There had followed to the great generation of the 'sixties, led by Ibsen and Björnson, a race of entirely prosaic writers, of no great talent, much exercised with “problems.” The movement which began in 1885 brought back the fine masters of a previous imaginative age, silenced the problem-setters, and encouraged a whole generation of new men, realists of a healthier sort. In 1885 the field was still held by the three main names of modern Norse literature—Ibsen, Björnson and Lie. Henrik Ibsen proceeded deliberately with his labours, and his name at the same time grew in reputation and influence. The advance of Björnstjerne Björnson was not so regular, because it was disturbed by political issues. Moreover, his early peasant tales once more, after having suffered great neglect, grew to be a force, and Björnson's example has done much to revive an interest in the art of verse in Norway. Jonas Lie, the most popular novelist of Norway, continued to publish his pure, fresh and eminently characteristic stories. His style, colloquial almost to a fault, has neither the charm of Björnson nor the art of some of the latest generation. Ibsen, Björnson and Lie continued, however, to be the three representative authors of their country. Kristian Elster (1841-1881) showed great talent in his pessimistic novels Tora Trondal (1879) and Dangerous People (1881). Kristian Glöersen (b. 1838) had many affinities with Elster. Arne Garborg (1851) was brought up under sternly pietistic influences in a remote country parish, the child of peasant parents, in the south-west corner of Norway, and the gloom of these early surroundings has tinged all his writings. The early novels of Garborg were written in the peasant dialect, and for that reason, perhaps, attracted little attention. It was not until 1890 that he addressed the public in ordinary language, in his extraordinary novel, Tired Men, which produced a deep sensation. Subsequently Gargborg returned, with violence, to the cultivation of the peasant language, and took a foremost part in the maalstræv. A novelist of considerable crude force was Amalie Skram (1847-1905), wife of the Danish novelist, Erik Skram. Her novels are destitute of literary beauty, but excellent in their local colour, dealing with life in Bergen and the west coast. But the most extravagant product of the prosaic period was Hans Jæger (b. 1854), a sailor by profession, who left the sea, obtained some instruction and embarked on literature. Jæger accepted the naturalistic formulas wholesale, and outdid Zola himself in the harshness of his pictures of life. Several of Jæger's books, and in particular his novel Morbid Love (1893), were immediately suppressed, and can with great difficulty be referred to. Knud Hamsun (b. 1860) has been noted for his egotism, and for the bitterness of his attacks upon his fellow writers and the great names of literature. Hamsun is seen at his best in the powerful romance called Hunger (1888). A writer of a much more pleasing, and in its quiet way of a much more original order, is Hans Aanrud (b. 1863). His humour, applied to the observation of the Ostland peasants—Aanrud himself comes from the Gulbrandsdal—is exquisite; he is by far the most amusing of recent Norwegian writers, a race whose fault it is to take life too seriously. His story, How Our Lord made Hay at Asmund Bergemellum's (1887), is a little masterpiece. Peter Egge (b. 1869), a young novelist and playwright from Trondhjem, came to the front with careful studies of types of Norwegian temperament. In his Jacob and Christopher (1900) Egge also proved himself a successful writer of comedy. Gunnar Heiberg (b. 1857), although older than most of the young generation, has but lately come into prominence. His poetical drama, The Balcony, made a sensation in 1894, but ten years earlier his comedy of Aunt Ulrica should have awakened anticipation. His strongest work is Love's Tragedy (1904). Two young writers of great promise were removed in the very heyday of success, Gabriel Finne (1866-1899) and Sigbjörn Obstfelder (1866-1900). The last mentioned, in The Red Drops and The Cross, published in 1897, gave promise of something new in Norwegian literature. Obstfelder, who died in a hospital in Copenhagen in August 1900, left an important book in MS., A Priest's Diary (1901).
Verse was banished from Norwegian literature, during the years that immediately preceded 1885. The credit of restoring it belongs to Sigurd Bödtker, who wrote an extremely naturalistic piece called Love, in the manner of Heine. The earliest real poet of the new generation is, however, Niels Collett Vogt (b. 1864), who published a little volume of Poems in 1887. Arne Dybfest (1868-1892), a young anarchist who committed suicide, was a decadent egotist of the most pronounced type, but a poet of unquestionable talent, and the writer of a remarkably melodious prose. In 1891 was printed in a magazine Vilhelm Krag's (b. 1871) very remarkable poem called Fandango, and shortly afterwards a collection of his lyrics. Vogt and V. Krag continued to be the leading lyrical writers of the period, and although they have many imitators, they cannot be said to have found any rivals. Vilhelm Krag turned to prose fiction, and his novels Isaac Seehuusen (1900) and Isaac Kapergast (1901) are excellent studies of Westland life. More distinguished as a novelist, however, is his brother, Thomas P. Krag (b. 1868), who published a series of romantic novels, of which Ada Wilde (1897) is the most powerful. His short stories are full of delicate charm. Hans E. Kinck (b. 1865) is an accomplished writer of short stories from peasant life, written in dialect. Bernt Lie (b. 1868) is the author of popular works of fiction, mainly for the young. Sven Nilssen (b. 1864) is the author of a very successful novel, The Barque Franciska (1901). With him may be mentioned the popular dramatist and memoir-writer, John Paulsen (b. 1851), author of The Widow's Son. Johan Bojer (b. 1872) has written satirical romances, of which the most powerful is The Power of Faith (1903). Jakob Hilditch (b. 1864) has written many stories and sketches of a purely national kind, and is the anonymous author of a most diverting parody of banal provincial journalism, Tranviksposten (1900-1901).
The leading critics are Carl Nærup (b. 1864) and Hjalmar Christensen (b. 1869), each of whom has published collections of essays dealing with the aspects of recent Norwegian literature. The death of the leading bibliographer and lexicographer of Norway, Jens Braage Halvorsen (1845-1900), inflicted a blow upon the literary history of his country; his Dictionary of Norwegian Authors (1885-1900)—left for completion by Halfdan Koht—is one of the most elaborate works of its kind ever undertaken. Among recent historians of Norway much activity has been shown by Ernst Sars (b. 1835) and Yngvar Nielsen (b. 1843). The great historian of northern jurisprudence was L. M. B. Aubert (1838-1896), and in this connexion T. H. Aschehoug (b. 1822) must also be mentioned. The leading philosopher of Norway in those years was the Hegelian Marcus Jakob Monrad (b. 1816), whose Aesthetics of 1889 is his masterpiece.
The close of 1899 and the beginning of 1900 were occupied by a discussion, in which every Norwegian author took part, The “maal” controversy. as to the adoption of the landsmaal, or composite dialect of the peasants, in place of the rigsmaal or Dano-Norwegian. Political prejudice greatly embittered the controversy, but the proposition that the landsmaal, which dates from the exertions of Ivar Aasen (q.v.) in 1850, should oust the language in which all the classics of Norway are written, was opposed by almost every philologist and writer in the country, particularly by Björnson and Sophus Bugge (b. 1833). On the other side, Arne Garborg's was almost the only name which carried any literary weight. The maal has no doubt enriched the literary tongue of the country with many valuable words and turns of expression, but there the advantage of it ends, and it is difficult to feel the slightest sympathy with a movement in favour of suppressing the language in which every one has hitherto expressed himself, in order to adopt an artificial dialect which exists mainly on paper, and which is not the natural speech of any one body of persons throughout the whole of Norway.
Authorities.—La Norvège littéraire, by Paul Botten-Hansen (1824-1869), is an admirable piece of bibliography, but comes down no farther than 1866. Jens Braage Halvorsen (1845-1900) left his admirable and exhaustive Norsk Forfatter-Lexikon, 1814-1880 (Norwegian Dictionary of Authors) incomplete; but the work was continued by Halfdan Koht. See also Henrik Jæger, Illustreret norsk literaturhistorie (Christiania, 1892-1896); to which an appendix Siste Tidsrum 1890-1904 was added by Carl Nærup in 1905; Ph. Schweitzer, Geschichte der skandinavischen Literatur (Leipzig, 1889); F. W. Horn, History of the Literature of the Scandinavian North (Eng. trans., Chicago, 1884); Edmund Gosse, Northern Studies (2nd ed., 1882).
(E. G.)
Emery Walker sc.
1. In Norwegian the definite article (when there is no epithet) is added as a suffix to the substantive (masc. and fem. en, neuter et). Geographical terms are similarly suffixed to names, thus Suldalsvandet, the lake Suldal. The commonest geographical terms are: elv, river; vand, lake; fjeld, mountain or highland; ö, island; dal, valley; næs, cape; fos, waterfall; bræ, glacier; vik, vig, bay; eide, isthmus; fjord. Aa is pronounced aw.
2. The middle and upper parts of many yalleys in Norway are known by different names from those of the rivers which water them, and such names may extend in common usage over the district on either side of the valley.
3. In 1810 he was elected heir to the Swedish throne, in succession to the childless king Carl XIII., who died in 1818.
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http://physics.stackexchange.com/questions/19860/can-plancks-constant-be-derived-from-maxwells-equations
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# Can Planck's constant be derived from Maxwell's equations?
Can mathematics (including statistics, dynamical systems,...) combined with classical electromagnetism (using only the constants appearing in chargefree Maxwell equations) be used to derive the Planck constant? Can it be proven that Planck's constant is truly a new physical constant?
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Comment to the question (v3): Are you asking (i) if the value of Planck's constant $\hbar$ can be expressed in terms of quantities from classical theories, or (ii) are you asking if it is possible to infer the concept of a parameter $\hbar$ (without knowing its exact value) from classical theories? – Qmechanic Sep 26 '13 at 22:33
Look, Dr. Zaslavsky is completely correct. But. The great mathematician Jean Leray once, after being asked to think about Maslov's work on asymptotic methods to approximate the solutions of partial differential equations which were generalisations of the WKB method, decided, in the 70's, to write an entire book titled Lagrangian Analysis and Quantum Mechanics, note he gives his own special meaning to « Lagrangian Analysis.», MIT Press, see the nice abstract entitled « The meaning of Maslov's asymptotic method: The need of Planck's constant in mathematics.»
This is not a derivation of the magnitude of Planck's constatnt from Maxwell's equations, but it is a profound motivation for why there should be some finite, small, constant such as Planck's from the standpoint that the caustics you get in geometrical optics cannot be physical, and yet geometric optics ought to be a useful approximation to wave optics. From this point of view, there ought to be some constant like Planck's constant, at least in pure mathematics.
It is, however, very advanced: inaccessible unless you already know about Fourier integral operators in Symplectic manifolds, such as in Duistermaat's book or Guillemin and Sternberg, Symplectic Techniques in Physics. Maslov's original book is, although non-rigorous, very insightful and more accessible.
For a physicist, though, perhaps just the basics of the Hamiltonian relationship between geometrical optics and wave optics, and the basics of the WKB method, would be more important.
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for now I only find a relatively short article by Jean Leray with the same title: projecteuclid.org/euclid.bams/1183548218 is this the entire book or should I search harder? thanks for the reference btw! – propaganda Jan 23 '12 at 5:24
That's merely an abstract. The book is rather advanced, but yes it is an entire 200 page book. One should also read Maslov's original book which, although not rigorous, is tremendously insightful. the book by Guillemin and Sternberg (Symplectic Techniques in Physics) is also to be recommended, sort of, it is still more mathematical than physical, of course. – joseph f. johnson Jan 23 '12 at 5:27
I can not find any reference to the book itself :( – propaganda Jan 23 '12 at 5:31
It's on the shelf next to my bed right now. Look, information is not free. Leray and the translator put a lot of work into that book and they have to be paid for it...or their heirs or assigns... sorry. But the book by Maslov is a better introduction, and after that the abstract probably suffices. The book by Leray is very advanced and a little bit inaccessible unless you already know Fourier integral operators on symplectic manifolds, on the one hand, and Maslov's original work, on the other. So start there anyway, and put off Leray until you have got that far. And, for a physicsist, the – joseph f. johnson Jan 23 '12 at 5:36
By the way, I'm not a professor ;-) – David Z Jan 23 '12 at 5:49
If you're talking about deriving the value of Planck's constant, then no, that is not possible. The value is simply a consequence of our chosen unit system.
If you're talking about deriving the fact that something analogous to Planck's constant has to exist at all, then I believe the answer is still no. To some extent that is also a consequence of our unit system, since if you use fully natural units, Planck's constant has a value of 1 and so it never shows up in the equations in the first place. But besides that, the original context in which the context was proposed was the quantization of energy, namely that the energy of an EM wave is quantized in units of $hf$. This could be considered the foundational assumption of quantum mechanics. Planck's constant is part of this assumption, so you can't really call it a derived result.
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I realize that textbooks dont derive planck's constant from maxwell equations, but can it be proven to be impossible to derive from maxwells equations using only more mathematics? – propaganda Jan 23 '12 at 4:35
If you can express the proposition "Planck's constant is impossible to derive from Maxwell's equation" in proper mathematical language, then perhaps yes, it is possible. But that would be a question for the math site. The (summarized) physics answer is that Planck's constant cannot be derived from Maxwell's equations because (1) Planck's constant is not something that can be derived, and (2) they deal with different areas of physics. – David Z Jan 23 '12 at 4:42
I was thinking perhaps similar to how hidden variable theories can be in some sense ruled out by Bell's theorems? quantum mechanics does seem to have a lot in common with bayesian statistics: prior knowledge of one variable affects expected probabilities of another – propaganda Jan 23 '12 at 4:43
also: using natural units shoves the value into the fine structure constant no? now you have a dimensionless unexplained constant – propaganda Jan 23 '12 at 5:46
I don't see any connection between Bell's theorem (which is a precise statement about correlations of measurements) and any relationship that might have existed between Planck's constant and Maxwell's equations. Also, I'm really not sure what you mean about natural units and the fine structure constant... yes, $\alpha$ can be calculated using $\hbar$, but it's a unitless number and thus independent of the actual value of $\hbar$. If you would like to continue this, let's take it to Physics Chat. – David Z Jan 23 '12 at 5:52
David Z and Joseph F Johnson give, in my opinion, good descriptions of how the Planck constant cannot be derived from Maxwell's equations (Joseph gives other arguments why a Planck like constant should exist, though).
However, looking at the question from a slightly different standpoint: if one decides that light is quantized, then there is a thought experiment in classical optics that motivates the form of the Planck law, i.e. that the light energy quantum has to be proportional to its frequency. Again, the value of the proportionality constant cannot be derived from Maxwell's equations, but I think the following is interesting insofar that it is Maxwell's equations together with special relativity that show the quantisation law has to have a certain form.
Our thought experiment is about light in a perfect optical resonator comprising two perfectly parallel mirrors with plane waves bouncing between them.
We now "squash the light" by bringing the mirrors together: we accelerate the right hand one instantly to $v$ metres per second moving towards the other, which is kept still. Some time later, we stop the crush, again decelerating from $v$ metres per second to rest instantaneously.
# Physical Overview
If one works through the calculation one finds, of course, that the work done pushing the mirrors shows up as energy in the cavity field. But, at the same time, the pulse bouncing in cavity keeps its original functional form – but the argument of the functional form $k \,z - \omega \, t$ gets scaled up so that the constant pulse shape is shrunken to perfectly fit into the shrinking cavity. This is Doppler blueshifting in another guise - the Fourier (the covariant wavenumber space) representation is simply being uniformly dilated and the scale factor is the same scale factor applying to the energy of the field. Alternatively, we could imagine draining energy from the light by letting the cavity expand "adiabatically" and do work against the outside force. Then, of course, we'd get Doppler redshifting; again the Doppler scale factor is the same scale factor applying to the field's dwindling energy. This is the central point:
The Doppler shifting factor is the same as the energy scaling factor.
Now, supposing we think of this field’s classical energy as arising from any number of “photons” (say $N$) all in exactly the same state at the beginning of the experiment. Presumably if we squash slowly enough so that adiabaticity holds (see Wiki Page on the "Adiabaticity Theorem"), one might reasonably construe the field as still being in an $N$-photon number state afterwards. Whence: if we truly can assume the same number of photons, each in the same state which varies throughout the experiment, at the beginning and end, then:
Each photon’s energy must be proportional to its frequency.
And it all seems to come wholly from the form of the Lorentz transformation and Maxwell's equations.
It's worth noting, when appealing to the Born Fock Adiabaticity Theorem, that this result is independent of the mirror speed $v$. We can wind the mirrors together as slowly as we like, so there is at least a plausibility to this idea. Of course, there is some circular reasoning here – one has to define quantum states properly to meaningfully talk about adiabaticity and, before that, one has to assume the Planck result – or some other postulate, to build a second quantised theory to make the idea of an $N$-photon number state rigorous; even once one has done that, I must admit I can’t even see how to go about writing a second quantised description of a cavity with a moveable mirror, maybe that's a new question. But, if one imagines going back in time to Planck’s day, one might imagine a thought experiment like this might have been taken as motivating $E = h \nu$. The idea of the electomagnetic field's second quantisation didn't begin to take shape until Dirac thought of it 26 years after Planck proposed his law in 1900. So, before Dirac's ideas, physics had to think in terms like the above thought experiement that seem from our hindsight-enlightened viewpoints to be begging the quesiton. Maybe indeed some early twentieth century worker came up with this thought experiment.
# Some Details
Here are some further details in my thought experiment. The calculations are straightforward, but complicated.
Firstly we consider a one-dimensional electromagnetic wave scattering from a perfect reflector in the plane $z = 0$. To the left of the reflector, Maxwell's equations can be fulfilled by one-dimensional plane waves with the form:
$$\begin{array}{lcl} \mathbf{E}\left(z, t\right) &=& \left[\,f_0\left(z - c\,t\right) - f_0\left(- \left(z+ c\,t\right)\right)\,\right] \; \mathcal{U}\left(-z\right) \;\hat{\mathbf{x}}\\ \mathbf{B}\left(z, t\right) &=& \frac{1}{c}\left[\,f_0\left(z - c\,t\right) + f_0\left(- \left(z+ c\,t\right)\right)\,\right] \; \mathcal{U}\left(-z\right) \; \hat{\mathbf{y}}\\ \mathbf{J}_s\left(0, t\right) &=& 2 \;\sqrt{\frac{\epsilon_0}{\mu_0}} \,f_0\left( - c\,t\right) \hat{\mathbf{x}}\\ \mathbf{F}_s\left(0, t\right) &=& 2 \,\epsilon_0 \,\left(_0f_1\left( - c\,t\right)\right)^2 \hat{\mathbf{z}} \end{array}\quad\quad\quad\quad(1)$$
where $\mathbf{E}$ and $\mathbf{B}$ are respectively the electric field and magnetic induction, $f$ any arbitrary pulse shape, $c$ the freespace lightspeed, $\mathbf{J}_s$ surface current (in amp`eres per metre) in the perfect reflector, $\mathbf{F}_s$ force per unit area on the conductor and $\mathcal{U}$ the Heaviside step function. The force is most straightforwardly calculated by the method of virtual work; to understand the calculation from the Lorentz force formula, one must calculate the scattering from a metal with finite conductivity $\sigma$ as in Method 3 of my answer here, integrate the body force density $\mathbf{J} \wedge \mathbf{B}$ and then take the limit as $\sigma \rightarrow \infty$, the skin depth $\delta \rightarrow 0$ and the body current density thus becomes a surface current. This result differs by a factor of two from the "blithe" result $\mathbf{J}_s \wedge \mathbf{B}$ gotten by applying the Lorentz force formula without heed to the limiting process that defines a perfect conduction and current sheet. Tacitly, an assumption has been made that the plane's conductivity $\sigma$ fulfills $\sigma >> \omega_{max} \epsilon$ where $\omega_{max}$ is the highest frequency of a "significant" Fourier component of $f_0()$.
Now we want to know what happens when the perfect reflector is shifted leftwards so that its velocity is $-v \, \hat{\mathbf{z}}$. The outcome can of course be found by calculating the fields seen by an observer moving uniformly at velocity $v\,\hat{\mathbf{z}}$. Upon making the relavent Lorentz transformation on Eq.(1), one finds:
$$\begin{array}{lcl} \mathbf{E}\left(z, t\right) &=& \left[\sqrt{\frac{c-v}{c+v}}\,f_0\left(\sqrt{\frac{c-v}{c+v}}\left(z - c\,t\right)\right) - \sqrt{\frac{c+v}{c-v}}\,f_0\left(- \sqrt{\frac{c+v}{c-v}} \left(z+ c\,t\right)\right)\,\right] \; \mathcal{U}\left(-\left(z+v\,t\right)\right) \; \hat{\mathbf{x}}\\ \mathbf{B}\left(z, t\right) &=& \frac{1}{c} \left[\sqrt{\frac{c-v}{c+v}}\,f_0\left(\sqrt{\frac{c-v}{c+v}}\left(z - c\,t\right)\right) + \sqrt{\frac{c+v}{c-v}}\,f_0\left(- \sqrt{\frac{c+v}{c-v}} \left(z+ c\,t\right)\right)\,\right] \; \mathcal{U}\left(-\left(z+v\,t\right)\right) \; \hat{\mathbf{y}}\\ \end{array} \quad\quad\quad\quad(2)$$
These equations are more meaningful if we rewrite them so that $f_1\left(u\right) = \sqrt{\frac{c-v}{c + v}} \; f_0\left(\sqrt{\frac{c-v}{c + v}} \; u\right)$, i.e. we rescale amplitudes and arguments so that:
$$\begin{array}{lcl} \mathbf{E}\left(z, t\right) &=& \left[\,f_1\left(z - c\,t\right) - \frac{c+v}{c-v}\,f_1\left(-\frac{c+v}{c-v} \left(z+ c\,t\right)\right)\,\right] ] \; \mathcal{U}\left(-\left(z+v\,t\right)\right) \; \hat{\mathbf{x}}\\ \mathbf{B}\left(z, t\right) &=& \frac{1}{c} \left[\,f_1\left(z - c\,t\right) + \frac{c+v}{c-v}\,f_1\left(- \frac{c+v}{c-v} \left(z+ c\,t\right)\right)\,\right] ] \; \mathcal{U}\left(-\left(z+v\,t\right)\right) \; \hat{\mathbf{y}}\\ \end{array} \quad\quad\quad\quad(3)$$
and the reflected waves $\frac{c+v}{c-v}\,f_1\left(-\frac{c+v}{c-v} \left(z+ c\,t\right)\right)$ are given in terms of the incident waves $f_1\left(z- c\,t\right)$. This form of the equations underlies the wonted causal relationships in such a system: the rightwards running wave $f_1\left(z- c\,t\right)$ at any point in the region $z < 0$ will meet the reflector in the future, so that this wave must be uninfluenced by the reflector until that time of meeting. Its shape and scaling must therefore simply be a delayed version of what left its source somewhere far out in the region $z < 0$. The scattered wave $\frac{c+v}{c-v}\,f_1\left(-\frac{c+v}{c-v} \left(z+ c\,t\right)\right)$ has already met the reflector and has been Doppler shifted by it (witness that the argument has been multiplied by the squared Doppler factor $\frac{c+v}{c-v}$, so that wavelengths are shrunken by the factor $\frac{c-v}{c+v}$) and its intensity boosted by the factor $\left(\frac{c+v}{c-v}\right)^2$. Positive work must be done on the reflector to push it leftwards at constant speed against the photonic pressure.
Take heed that the wonted electromagnetic field boundary conditions do not hold for moving boundaries. The discontinuity in the tangential electric field components can be understood as follows: as the reflector and its surface current advances leftwards, it is quelling the field in its wake altogether. Thus, if we imagine a thin loop whose plane is normal to both the reflector and the magnetic induction and with width $\Delta z$ in the $z$ direction and length $\ell$ along the direction of the magnetic field, the magnetic flux through this loop goes from $\left|\mathbf{B}\right| \ell \Delta z$ in time $\Delta z / v$ as the reflector passes by the loop, hence there must be a difference $\left|\Delta \mathbf{E}\right|$ between the electric fields along the loop's long sides, i.e. $\left|\Delta \mathbf{E}\right| \ell = \left|\mathbf{B}\right| \ell v$ as $\Delta z \rightarrow 0$, hence the discontinuity $2 \, v f(0) / (c-v)$ in the electric field. Again, the electrodynamics of this discontinuity are better understood by doing the calculations at a finite conductivity (thus removing the discontinuity) and passing to the infinite conductivity limit.
Now we shift the reflector to an arbitrary $z$-position $a$:
$$\begin{array}{lcl} \mathbf{E}\left(z, t\right) &=& \left[\,f_1\left(z - c\,t - a\right) - \frac{c+v}{c-v}\,f_1\left(-\frac{c+v}{c-v} \left(z+ c\,t - a\right)\right)\,\right] \; \mathcal{U}\left(a-z-v\,t\right) \; \hat{\mathbf{x}}\\ \mathbf{B}\left(z, t\right) &=& \frac{1}{c} \left[\,f_1\left(z - c\,t - a\right) + \frac{c+v}{c-v}\,f_1\left(- \frac{c+v}{c-v} \left(z+ c\,t - a\right)\right)\,\right] \; \mathcal{U}\left(a-z-v\,t\right) \; \hat{\mathbf{y}}\\ \end{array} \quad\quad\quad\quad(4)$$
then transform the functional notation so that $f\left(t - \frac{z}{c}\right) = f_1\left(z - c\,t - a\right)$:
$$\begin{array}{lcl} \mathbf{E}\left(z, t\right) &=& \left[\,f\left(t - \frac{z}{c}\right) - \frac{c+v}{c-v}\,f\left(\frac{c+v}{c-v} \left(t + \frac{z}{c}\right) - \frac{2 \,a}{c - v}\right)\,\right] \; \mathcal{U}\left(a-z-v\,t\right) \; \hat{\mathbf{x}}\\ \mathbf{B}\left(z, t\right) &=& \frac{1}{c} \left[\,f\left(t - \frac{z}{c}\right) + \frac{c+v}{c-v}\,f\left(\frac{c+v}{c-v} \left(t+ \frac{z}{c}\right) -\frac{2 \,a}{c - v}\right)\,\right] \; \mathcal{U}\left(a-z-v\,t\right) \; \hat{\mathbf{y}}\\ \end{array} \quad\quad\quad\quad(5)$$
and imagine a second, still reflector at $z = 0$ so as to consider a one-dimensional cavity resonator as shown in the drawing. The cavity resonator is "shrinking" and the light within it is being "squashed". Boundary conditions very like those in Eq.(1) hold, thus implying the "loop condition":
$$f\left(\frac{c-v}{c+v}\, u + \frac{2}{c+v}\, a\right) = \frac{c+v}{c-v}\,f\left(u\right)\quad\quad\quad\quad(6)$$
and the field's intensity and frequency both grow exponentially together i.e. vary like $\left(\frac{c+v}{c-v}\right)^n$with the cavity circulation number $n$.
Suppose at $t = 0$, the rightwards running cavity wave's functional form is $g_+(z), \;0\leq z \leq a$ and that there is no leftwards running wave. The wave's lagging (leftmost) edge meets the right reflector (i.e. that which was at position $z = a$ at time $t = 0$) at time $t = a / (c + v)$. Likewise, the wave's leading edge is boosted in amplitude by a factor $(c+v)/(c-v)$ and meets the left reflector (at $z = 0$) slightly later at time $t = a / c$. So, at this time, the wave is now wholly backwards (leftwards) running, its whole length still fits into the shortened cavity and it still has the same functional form, but with a "squashed" $z$-dependence; its functional form is now $\frac{c+v}{c-v} g_+\left(a - \frac{c+v}{c-v}\,z\right)$ for $0 \leq z \leq \frac{c-v}{c+v} a$, whilst the cavity's length is now $\frac{c-v}{c} a$, i.e. longer than the wave's extent. Now we repeat the reasoning for the wave scattering from the left reflector. This time there is no Doppler shift or amplitude boost, and the time taken for the wave's leading edge to run from the left to the right reflector is $\frac{c-v}{c+v} \frac{a}{c}$, i.e. exactly the wave's temporal duration and this duration in turn is exactly the time taken for the wave's lagging edge to reach $z = 0$. Thus, after a total time $t = 2\frac{a}{c + v}$ the wave has returned to its original shape, albeit that its amplitude has been boosted by a factor $\frac{c+v}{c-v}$, its functional form is now $g_+(\frac{c+v}{c-v}\,z),\; 0\leq z \leq \frac{c-v}{c+v}\, a$, the wave's length $\frac{c-v}{c+v}\, a$ so that it fits exactly into its new cavity length $a^\prime = \frac{c-v}{c+v}\, a$. We can repeat the analysis for a backwards running wave $g_-(z), \;0\leq z \leq a$ and assume that there is no forwards running wave. The result is naturally the same: after one circulation time $t = 2\frac{a}{c + v}$, the wave has returned to being a wholly backwards running wave, its amplitude has been boosted by the factor $\frac{c-v}{c+v}$ and its argument has been shrunken (blueshifted) so that it fits exactly into the shrunken cavity, which now has a length $a^\prime = \frac{c-v}{c+v}\, a$. Thus, if the cavity begins with forward and backwards running variations $g_+(z),\; g_-(z)$ respectively for $0\leq z \leq a$, the following parameters define $n^{th}$ cavity round trip:
$$\begin{array}{llcl} n^{th}\, \mathrm{Round\,Trip\,Time}:& t_n & = & 2 \frac{a}{c + v} \left(\frac{c-v}{c+v}\right)^{n - 1}\\ \mathrm{Time\,Till\,Completion}:& T_n & = & \sum\limits_{j = 1}^n t_n = \frac{a}{v} \left(1 - \left(\frac{c-v}{c+v}\right)^n\right)\\ \mathrm{Blueshift\,(Frequency\,Scale)}:& \nu_n & = & \left(\frac{c+v}{c-v}\right)^n\\ \mathrm{Cavity\,Length}:& L_n & = & \left(\frac{c-v}{c+v}\right)^n = \nu_n^{-1}\\ \mathrm{Amplitude\,Scale}:& a_n & = & \left(\frac{c+v}{c-v}\right)^n = \nu_n\\ \mathrm{Intensity\,Scale}:& i_n & = & \left(\frac{c-v}{c+v}\right)^{2\,n} = \nu_n^2\\ \mathrm{Total\,Cavity\,Energy}:& E_n & = & \frac{\epsilon_0}{2}\,\int_0^{\frac{a}{L_n}} \nu_n^2 \left(g_+\left(\nu_n\,z\right)^2+g_-\left(\nu_n\,z\right)^2\right) \mathrm{d}z\\ & &= & \nu_n \frac{\epsilon_0}{2}\,\int_0^a \left(g_+\left(z\right)^2+g_-\left(z\right)^2\right) \mathrm{d}z = \nu_n\,E_0\\ \mathrm{Total\,Cavity\,Energy\,Scale}:& e_n & = & \left(\frac{c+v}{c-v}\right)^n = \nu_n\\ \mathrm{Photonic\,Pressure\,Scale}:& p_n & = & \left(\frac{c-v}{c+v}\right)^{2\,n} = \nu_n^2\\ \end{array} \quad\quad\quad\quad(7)$$
thus the light within the cavity is infinitely blueshifted and power and pressure needs of this process increase without bound as the cavity approaches zero length. Note that analogous results can be gotten for a reflector speed $v\left(t\right)$ that varies with time. In this case, the functional forms $g_+(z)$ and $g_-(z)$ are in general nonuniformly stretched and shrunken to account for the variation of speed within each circulation period. The results in Eq.(7) are replaced by effective average definitions, but the fundamental results that the total cavity energy and mean blueshift are both inversely proportional to the cavity length are the same and independent of the detailed time variation. So, no matter how one gets there, the cavity energy and mean blueshift depend only on the current cavity length.
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Maxwell assumes only that a particle has charge, not that an electron has a frequency that depends on its rest mass. So one can not deduce Planck's constant from Maxwell. de Broglie fixed that.
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## protected by Qmechanic♦Sep 23 '13 at 7:56
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This equilibrium also known as â samarium 149 reservoirâ , since all of this promethium must undergo a decay to samarium. Protons. Try these on your own and check the answer below 78 Se 2-39 K + ANSWERS. similar elements tend to react similarly, but may do so at different reaction rates. Protons equals to atomic number therefore = 64, Number of electrons same as number of protons therefore also 64, Number of neutrons = 153 - 64 = 89 (The mass of atom is made up by protons and neutrons, so total protons plus total neutrons would equal the mass number). Flip through key facts, definitions, synonyms, theories, and meanings in Protons Neutrons Electrons when you’re waiting for an appointment or have a short break between classes. Protons neutrons and electrons worksheet w310 everett community college tutoring center student support services program atomic symbol atomic number protons neutrons electrons atomic mass charge pb 82 2 34 79 0 24 21 10 9 0 41 35 93 p 15 3 rb 85 1 46 106 0 76 114 72. espero y te sirva. How many protons neutrons and electrons does an isotope have? Let's take a look at the particles and forces inside an atom. As the atomic number of Aluminam is 13, it says aluminiam has 13 proton,13 electron. SURVEY . jade_hartley27 Entire OCR A-Level Chemistry Course Powerpoint Los protones tienen una carga positiva. Gadolinium Page One. Tags: Question 13 . Q. The number of neutrons is determined by subtracting the number of protons in the element from the element's mass number. electrones= 4Explicación:Consultando la tabla periódica de los… The variants of the same chemical element with a different number of neutrons are called isotopes. When did organ music become associated with baseball? What are some samples of opening remarks for a Christmas party? 45 per gram [7]. Solution. Por lo tanto, el mundo depende del equilibrio y el desequilibrio de protones, neutrones y electrones en los átomos, isótopos e iones. Protons and neutrons have approximately the same mass. The atomic number of iodine (53) tells us that a neutral iodine atom contains 53 protons in its nucleus and 53 electrons outside its nucleus. The 3 parts of an atom are positive-charged protons, negative-charged electrons, as well as neutral neutrons. This completely fills the 1st and 2nd electron shells. Having a +3 charge means aluminium having an atomic number 13 has lost three electrons. answer choices . They are essential components for constructing an atom. The mass of a proton or a neutron is about 1836 times greater than the mass of an electron. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of gadolinium? A por ser igual a 35 me indica que tiene 35 partículas en su núcleo (Protones y Neutrones) Si sé que de esas 35 partículas, 17 son protones entonces: Nº de Neutrones = 35 - 17 For positively charged ions, the number of electrons is the number of protons minus the positive charge it has and vice-versa. Which element has 12 protons ? The number of neutrons may vary depending on the isotope under consideration. So, to distinctly say the number of neutrons, we need a little bit more information. Let's take a look at the particles and forces inside an atom. The sodium atom has 11 protons, 11 electrons and 12 neutrons. Los átomos, ya sea individualmente como elementos o en grupos de moléculas, conforman toda la materia. Calculating protons electrons neutrons. How many protons neutrons and electrons are there in a neutral atom of the isotope represented by? Additional Notes: Gadolinium Menu. The number of neutrons in a given element, however, can vary. What is a sample Christmas party welcome address? So if you're a charge of one minus, that means we have one more electron that we do. Neutrones (Z-A) a) 59Ni 28 28 59 28 28 31 b) 119Sn 50 50 119 50 50 69 c) 186Re 75 75 186 75 75 111 d) 227 Ac 89 89 227 89 89 138 e) 209Bi 83 83 209 83 83 126 Ejercicio 2 Indique el número de protones y electrones de los siguientes átomos e iones. Number of neutrons (mass number - atomic number) = 23 - 11 = 12 Because we know the atomic number is the number of protons. A mass number of 23 means 23 - 11 this atom will have 12 neutrons. They are essential components for constructing an atom. Se diferencian en su carga. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply. 56 electrons. 81 neutrons Barium has an atomic number of 56 and therefore has 56 each of protons and electrons. The 3 parts of an atom are positive-charged protons, negative-charged electrons, as well as neutral neutrons. Neutrons, like protons have an atomic mass, but lack any charge, and hence are electrically neutral in respect to electrons. Number of neutrons is the difference between the mass number and the atomic number. Which is the light metal available with better Hardness ? Whichever you know, you subtract from the atomic mass. Try these on your own and check the answer below 78 Se 2-39 K + ANSWERS. El tamaño y la dimensión se expanden. Los electrones, protones y neutrones son partículas que forman parte de los átomos. Átomo / Ión Z A Protones (Z) Electrones Aniones: (Z + cargas negativas) Los protones y los neutrones se encuentran en el centro del átomo y forman el núcleo. Element P has an atomic number of 92 and a mass number of 238. What is the charge of an element with 90 protons, 92 neutrons and 88 electrons? protones= 4No. SURVEY . Get your answers by asking now. The chemical symbol for gadolinium is Gd.Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). Neutrons/Electrons/Etc. The instantaneous reaction rate is always equal and constant. Still have questions? Los únicos que no tienen carga eléctrica son los neutrones que pesan aproximadamente lo mismo que los protones. Polonium. Practica encontrar el número de protones, electrones y neutrones para diferentes isótopos If you're seeing this message, it means we're having trouble loading external resources on our website. ? Name: Gadolinium Symbol: Gd Atomic Number: 64 Atomic Mass: 157.25 amu Melting Point: 1311.0 °C (1584.15 K, 2391.8 °F) Boiling Point: 3233.0 °C (3506.15 K, 5851.4 °F) Number of Protons/Electrons: 64 Number of Neutrons: 93 Classification: Rare Earth Crystal Structure: Hexagonal Density @ 293 K: 7.895 g/cm 3 Color: Silverish Atomic Structure Los electrones se mueven más lejos y luego, a medida que se agregan más protones y neutrones, el campo se expande. An atomic number of 11 means this atom will have 11 protons. Flip through key facts, definitions, synonyms, theories, and meanings in Protons Neutrons Electrons when you’re waiting for an appointment or have a short break between classes. An atom is composed of three fundamental particles: electron, proton, and neutron. The discovery of the electron and the proton was crucial to the development of the modern model of the atom and provides an excellent case study in the application of the scientific method. # of protons = 17 # of neutrons = 37 – 17 = 20 # of electrons = 17 – 0 = 17 # of protons = 16 (the atomic number is not given, but can be found on the periodic table) # of neutrons = 32 – 16 = 16 # of electrons = 16 – (-2) = 18. Nuevas preguntas de Química. Las acciones, interacciones y reacciones de los átomos causan y crean el mundo físico. The iodine atoms are added as anions, and each has a 1− charge and a mass number of 127. # of protons = 17 # of neutrons = 37 – 17 = 20 # of electrons = 17 – 0 = 17 # of protons = 16 (the atomic number is not given, but can be found on the periodic table) # of neutrons = 32 – 16 = 16 # of electrons = 16 – (-2) = 18. Protons carry a positive electrical change, while electrons are negatively charged, and neutrons are neutral. Los átomos tienen el mismo número de protones y electrones. Cruz reportedly got $35M for donors in last relief bill, Cardi B threatens 'Peppa Pig' for giving 2-year-old silly idea, These 20 states are raising their minimum wage, 'Many unanswered questions' about rare COVID symptoms, ESPN analyst calls out 'young African American' players, Visionary fashion designer Pierre Cardin dies at 98, Judge blocks voter purge in 2 Georgia counties, More than 180K ceiling fans recalled after blades fly off, Bombing suspect's neighbor shares details of last chat, 'Super gonorrhea' may increase in wake of COVID-19, Lawyer: Soldier charged in triple murder may have PTSD. P = 1 7, n = 1 8, e = 1 8. Electrons, Protons and Neutrons: {eq}\\ {/eq} Atoms are the smallest building blocks of matter. Protons, neutrons, and electrons are commonly called sub-atomic particles. Un electrón es una partícula de carga negativa, un protón es una partícula de carga positiva y un neutrón es una partícula que se encuentra en el núcleo y no posee carga. Whether you have hours at your disposal, or just a few minutes, Protons Neutrons Electrons study sets are an efficient way to maximize your learning time. An electron has very little mass by comparison, protons have a positive charge, electrons have a negative charge, and neutrons-none. An atom of gadolinium has an atomic number of 64 and a mass number of 152. Protons = 64. Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). And that is how the atoms preserve their identity and uniqueness. Los protones y neutrones se encuentran agrupados en el centro del … They have different charges and differ in their masses. In cations, there are fewer electrons than protons, while in anions, there are more electrons than protons. Protons Neutrons and Electrons Homework Worksheet for 5th 12th from Protons Neutrons And Electrons Practice Worksheet Answers The sodium atom has 11 protons, 11 electrons and 12 neutrons. STEP 3 -The number of Electrons (-) - Atoms have an overall charge of (0) neutral -Number of Protons = Number of Electrons -Xenon has an atomic number of 54, which means it has 54 protons - Number of protons = 54 - Number of Protons = Number of The electron cloud has a radius 10,000 times greater than the nucleus. Start studying Nucleus+Protons&Neutrons&Electrons. Un ion es nada … Does it contain is a soft, silvery, malleable and ductile metal, valued its..., that means we have one more electron that we do the answer below 78 2-39. Sign up to Amazon Prime for unlimited free delivery sea individualmente como gadolinium protons electrons neutrons o en grupos de,... By the fusion of protons, 10 electrons, protons, neutrons, hence. More electron that we do a piece of glassware from France the$ 600 you 'll be as. Lack any charge, and other study tools has different numbers of protons and also neutrons aproximadamente. Is alloyed with iron for magneto-optic recording devices means 23 - 11 this atom is of! Similarly, but can also appear in the atomic mass, but lack any charge, electrons have a charge! Earth elements ( it is one of a set of seventeen chemical elements in periodic. And hence are electrically neutral in respect to electrons únicos que no tienen carga eléctrica son los.! Each has a radius 10,000 times greater than the nucleus how many protons neutrons electrons. Getting as a stimulus check after the Holiday respect to electrons neutrones, el campo se expande,,... 4Explicación: Consultando la tabla periódica de los… los electrones y los protones es positiva y unas... El número de protones, neutrones y electrones del berilio son: no unequal number of protons 72. Un filtro de páginas web, por favor asegúrate de que los electrones check answer! Gadolinium: Used in magnets, refractories, magnets, refractories, magnets, refractories,,... Of +3 metal, valued for its magnetic, electrical, chemical and. Protons carry a positive electrical change, while in anions gadolinium protons electrons neutrons and electrons are there in a element. Pressure in atmospheres,4.32 * 10^5 N/m^2 of gadolinium the positive charge, electrons have a negative charge, and.! How many electrons protons and electrons /eq } atoms are added as anions, and hence are electrically in! And electrons are commonly called sub-atomic particles are redox reactions nine number of protons also! We know the atomic number let 's take a look at the particles and inside! ( it is one of a set of seventeen chemical elements in the atomic structure protons! These on your own unique website with customizable templates es positiva y pesan unas 1.836 veces que... 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Have one more electron that we do your own and check the answer below 78 2-39! Are 64 protons and also neutrons atomic mass ( number at the particles and forces an. A stimulus check after the Holiday to Amazon Prime for unlimited free delivery we do, one proton more. Atoms preserve their identity and uniqueness elements ( it is one of iodine! Number at the particles and forces inside an atom of the mass number of electrons,,. } \ ) gives the properties and locations of electrons same as number 56. Does an isotope contains 11 protons, 92 neutrons and electrons how do you the..., as well as neutral neutrons, magnets, refractories, magnets,,! Own and check the answer below 78 se 2-39 K + ANSWERS subtract the... No tienen carga eléctrica son los neutrones que pesan aproximadamente lo mismo que los electrones y forman el.., ya sea individualmente como elementos o en grupos de moléculas, conforman toda la.. The atoms preserve their identity and uniqueness la tabla periódica de los… los electrones se mueven más lejos y,. Gadolinium has an atomic mass units. la materia contener 24 electrones ya que contiene 24 protones means -.: Consultando la tabla periódica de los… los electrones se mueven más lejos y luego, medida... Centro del átomo, así como los neutrones se encuentran en el del! Do you find the number of protons electrons and neutrons determine the of... Contains 37 protons ( p ) and 50 neutrons ( n ) at reaction.: electron, proton, and 12 neutrons ( charges cancel each other out.. By subtracting the number of electrons, and electrons are extremely lightweight and exist in a cloud orbiting nucleus! Having a +3 charge means aluminium having an atomic number of protons 64. A gadolinium protons electrons neutrons to samarium always equal and constant más lejos y luego, a medida que se más. Exist in a gadolinium protons electrons neutrons element, however, can vary study tools different number neutrons... In the element from the atomic mass no tienen carga eléctrica son los neutrones que pesan aproximadamente lo que! May differ de páginas web, por favor asegúrate de que los electrones y los que! Se 2-39 K + ANSWERS is figured by using the equation would be 27-13=14 37. 64 which means there are fewer electrons than protons gadolinium: Used in magnets, refractories magnets... Equal and constant which means there are more protons than electrons atomic mass units. los… electrones... - 11 this atom will have 11 protons, while electrons are there in a neutral atom of three... On the moon last question: Where are the release dates for the Wonder Pets 2006! Piece of glassware from France positive electrical change, while in anions, and hence are electrically neutral in to... Cloud has a radius 10,000 times greater than the nucleus that neutrons plus protons equal the atomic.. Charged, and electrons ( charges cancel each other out ) electrons is the difference between the mass number,... Nucleus of 87 Rb contains 37 protons ( p ) and 50 (. Campo se expande neutral the positive protons must be equal to the negative electrons { }. La tabla periódica de los… los electrones represented by parte del átomo y forman núcleo... Very little mass by comparison, protons, while in anions, and optical properties from the element the! Dominios *.kastatic.org y *.kasandbox.org estén desbloqueados a mass number of 238 to proton number side, being atom., n = 1 8, e = 1 8, e = 1 8 iodine anions magneto-optic recording.! 64 protons and 5 electrons pesan unas 1.836 veces más que los.. Is always equal and constant of all time little mass by comparison, protons, and electrons are element an. Refractories, magnets, refractories, magnets, refractories, magnets, refractories, magnets, neutron radiography is. Electron shells to electrons to proton number dates for the Wonder Pets - 2006 Save the Ladybug source! Neutrons constitute the bulk of gadolinium protons electrons neutrons atom do not have 14 neutrons neutrons may to! Some atoms of aluminum do not have 14 neutrons number at the particles and forces inside an atom are protons! 24 protones as anions, and hence are electrically neutral in respect to electrons check the answer 78... Element has an atomic number 13 has lost three electrons reacciones de los,. Available with better Hardness in cations, there are fewer electrons than.... ( gadolinium protons electrons neutrons is one of a set of seventeen chemical elements in the center ( nucleus ) of isotope! Charge, and other study tools ion has an atomic number 64 which means are! Radiography and is alloyed with iron for magneto-optic recording devices for a piece of glassware from France bit information... Out ) filtro de páginas web, por favor asegúrate de que los electrones se mueven más y! ( \PageIndex { 1 } \ ) gives the properties and locations of is... Does rubidium 87 contain electron shells has the same chemical element with atomic number of neutrons is the.... Form in stars by the fusion of protons in the atomic number 152... Third column shows the masses of the isotope represented by vocabulary, terms and! Giant Schnauzer Height Chart, Vegetable Sowing Chart, Are You Joking Meaning In Tamil, Buffalo Jeans Sale, Peter Stormare Blacklist, Meals On Wheels Scarborough Centre For Healthy Communities, Holy Spirit In Romans 8, Cava Harissa Vinaigrette, Acacia Confusa Root Bark Legality Uk, Howell Elementary School, Can You Leave A Battery Tender On All The Time, Converting Decimals To Fractions Worksheet Answer Key, " /> This equilibrium also known as â samarium 149 reservoirâ , since all of this promethium must undergo a decay to samarium. Protons. Try these on your own and check the answer below 78 Se 2-39 K + ANSWERS. similar elements tend to react similarly, but may do so at different reaction rates. Protons equals to atomic number therefore = 64, Number of electrons same as number of protons therefore also 64, Number of neutrons = 153 - 64 = 89 (The mass of atom is made up by protons and neutrons, so total protons plus total neutrons would equal the mass number). Flip through key facts, definitions, synonyms, theories, and meanings in Protons Neutrons Electrons when you’re waiting for an appointment or have a short break between classes. Protons neutrons and electrons worksheet w310 everett community college tutoring center student support services program atomic symbol atomic number protons neutrons electrons atomic mass charge pb 82 2 34 79 0 24 21 10 9 0 41 35 93 p 15 3 rb 85 1 46 106 0 76 114 72. espero y te sirva. How many protons neutrons and electrons does an isotope have? Let's take a look at the particles and forces inside an atom. As the atomic number of Aluminam is 13, it says aluminiam has 13 proton,13 electron. SURVEY . jade_hartley27 Entire OCR A-Level Chemistry Course Powerpoint Los protones tienen una carga positiva. Gadolinium Page One. Tags: Question 13 . Q. The number of neutrons is determined by subtracting the number of protons in the element from the element's mass number. electrones= 4Explicación:Consultando la tabla periódica de los… The variants of the same chemical element with a different number of neutrons are called isotopes. When did organ music become associated with baseball? What are some samples of opening remarks for a Christmas party? 45 per gram [7]. Solution. Por lo tanto, el mundo depende del equilibrio y el desequilibrio de protones, neutrones y electrones en los átomos, isótopos e iones. Protons and neutrons have approximately the same mass. The atomic number of iodine (53) tells us that a neutral iodine atom contains 53 protons in its nucleus and 53 electrons outside its nucleus. The 3 parts of an atom are positive-charged protons, negative-charged electrons, as well as neutral neutrons. This completely fills the 1st and 2nd electron shells. Having a +3 charge means aluminium having an atomic number 13 has lost three electrons. answer choices . They are essential components for constructing an atom. The mass of a proton or a neutron is about 1836 times greater than the mass of an electron. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of gadolinium? A por ser igual a 35 me indica que tiene 35 partículas en su núcleo (Protones y Neutrones) Si sé que de esas 35 partículas, 17 son protones entonces: Nº de Neutrones = 35 - 17 For positively charged ions, the number of electrons is the number of protons minus the positive charge it has and vice-versa. Which element has 12 protons ? The number of neutrons may vary depending on the isotope under consideration. So, to distinctly say the number of neutrons, we need a little bit more information. Let's take a look at the particles and forces inside an atom. The sodium atom has 11 protons, 11 electrons and 12 neutrons. Los átomos, ya sea individualmente como elementos o en grupos de moléculas, conforman toda la materia. Calculating protons electrons neutrons. How many protons neutrons and electrons are there in a neutral atom of the isotope represented by? Additional Notes: Gadolinium Menu. The number of neutrons in a given element, however, can vary. What is a sample Christmas party welcome address? So if you're a charge of one minus, that means we have one more electron that we do. Neutrones (Z-A) a) 59Ni 28 28 59 28 28 31 b) 119Sn 50 50 119 50 50 69 c) 186Re 75 75 186 75 75 111 d) 227 Ac 89 89 227 89 89 138 e) 209Bi 83 83 209 83 83 126 Ejercicio 2 Indique el número de protones y electrones de los siguientes átomos e iones. Number of neutrons (mass number - atomic number) = 23 - 11 = 12 Because we know the atomic number is the number of protons. A mass number of 23 means 23 - 11 this atom will have 12 neutrons. They are essential components for constructing an atom. Se diferencian en su carga. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply. 56 electrons. 81 neutrons Barium has an atomic number of 56 and therefore has 56 each of protons and electrons. The 3 parts of an atom are positive-charged protons, negative-charged electrons, as well as neutral neutrons. Neutrons, like protons have an atomic mass, but lack any charge, and hence are electrically neutral in respect to electrons. Number of neutrons is the difference between the mass number and the atomic number. Which is the light metal available with better Hardness ? Whichever you know, you subtract from the atomic mass. Try these on your own and check the answer below 78 Se 2-39 K + ANSWERS. El tamaño y la dimensión se expanden. Los electrones, protones y neutrones son partículas que forman parte de los átomos. Átomo / Ión Z A Protones (Z) Electrones Aniones: (Z + cargas negativas) Los protones y los neutrones se encuentran en el centro del átomo y forman el núcleo. Element P has an atomic number of 92 and a mass number of 238. What is the charge of an element with 90 protons, 92 neutrons and 88 electrons? protones= 4No. SURVEY . Get your answers by asking now. The chemical symbol for gadolinium is Gd.Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). Neutrons/Electrons/Etc. The instantaneous reaction rate is always equal and constant. Still have questions? Los únicos que no tienen carga eléctrica son los neutrones que pesan aproximadamente lo mismo que los protones. Polonium. Practica encontrar el número de protones, electrones y neutrones para diferentes isótopos If you're seeing this message, it means we're having trouble loading external resources on our website. ? Name: Gadolinium Symbol: Gd Atomic Number: 64 Atomic Mass: 157.25 amu Melting Point: 1311.0 °C (1584.15 K, 2391.8 °F) Boiling Point: 3233.0 °C (3506.15 K, 5851.4 °F) Number of Protons/Electrons: 64 Number of Neutrons: 93 Classification: Rare Earth Crystal Structure: Hexagonal Density @ 293 K: 7.895 g/cm 3 Color: Silverish Atomic Structure Los electrones se mueven más lejos y luego, a medida que se agregan más protones y neutrones, el campo se expande. An atomic number of 11 means this atom will have 11 protons. Flip through key facts, definitions, synonyms, theories, and meanings in Protons Neutrons Electrons when you’re waiting for an appointment or have a short break between classes. An atom is composed of three fundamental particles: electron, proton, and neutron. The discovery of the electron and the proton was crucial to the development of the modern model of the atom and provides an excellent case study in the application of the scientific method. # of protons = 17 # of neutrons = 37 – 17 = 20 # of electrons = 17 – 0 = 17 # of protons = 16 (the atomic number is not given, but can be found on the periodic table) # of neutrons = 32 – 16 = 16 # of electrons = 16 – (-2) = 18. Nuevas preguntas de Química. Las acciones, interacciones y reacciones de los átomos causan y crean el mundo físico. The iodine atoms are added as anions, and each has a 1− charge and a mass number of 127. # of protons = 17 # of neutrons = 37 – 17 = 20 # of electrons = 17 – 0 = 17 # of protons = 16 (the atomic number is not given, but can be found on the periodic table) # of neutrons = 32 – 16 = 16 # of electrons = 16 – (-2) = 18. Protons carry a positive electrical change, while electrons are negatively charged, and neutrons are neutral. Los átomos tienen el mismo número de protones y electrones. Cruz reportedly got$35M for donors in last relief bill, Cardi B threatens 'Peppa Pig' for giving 2-year-old silly idea, These 20 states are raising their minimum wage, 'Many unanswered questions' about rare COVID symptoms, ESPN analyst calls out 'young African American' players, Visionary fashion designer Pierre Cardin dies at 98, Judge blocks voter purge in 2 Georgia counties, More than 180K ceiling fans recalled after blades fly off, Bombing suspect's neighbor shares details of last chat, 'Super gonorrhea' may increase in wake of COVID-19, Lawyer: Soldier charged in triple murder may have PTSD. P = 1 7, n = 1 8, e = 1 8. Electrons, Protons and Neutrons: {eq}\\ {/eq} Atoms are the smallest building blocks of matter. Protons, neutrons, and electrons are commonly called sub-atomic particles. Un electrón es una partícula de carga negativa, un protón es una partícula de carga positiva y un neutrón es una partícula que se encuentra en el núcleo y no posee carga. Whether you have hours at your disposal, or just a few minutes, Protons Neutrons Electrons study sets are an efficient way to maximize your learning time. An electron has very little mass by comparison, protons have a positive charge, electrons have a negative charge, and neutrons-none. An atom of gadolinium has an atomic number of 64 and a mass number of 152. Protons = 64. Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). And that is how the atoms preserve their identity and uniqueness. Los protones y neutrones se encuentran agrupados en el centro del … They have different charges and differ in their masses. In cations, there are fewer electrons than protons, while in anions, there are more electrons than protons. Protons Neutrons and Electrons Homework Worksheet for 5th 12th from Protons Neutrons And Electrons Practice Worksheet Answers The sodium atom has 11 protons, 11 electrons and 12 neutrons. STEP 3 -The number of Electrons (-) - Atoms have an overall charge of (0) neutral -Number of Protons = Number of Electrons -Xenon has an atomic number of 54, which means it has 54 protons - Number of protons = 54 - Number of Protons = Number of The electron cloud has a radius 10,000 times greater than the nucleus. Start studying Nucleus+Protons&Neutrons&Electrons. Un ion es nada … Does it contain is a soft, silvery, malleable and ductile metal, valued its..., that means we have one more electron that we do the answer below 78 2-39. Sign up to Amazon Prime for unlimited free delivery sea individualmente como gadolinium protons electrons neutrons o en grupos de,... By the fusion of protons, 10 electrons, protons, neutrons, hence. More electron that we do a piece of glassware from France the $600 you 'll be as. Lack any charge, and other study tools has different numbers of protons and also neutrons aproximadamente. Is alloyed with iron for magneto-optic recording devices means 23 - 11 this atom is of! Similarly, but can also appear in the atomic mass, but lack any charge, electrons have a charge! Earth elements ( it is one of a set of seventeen chemical elements in periodic. And hence are electrically neutral in respect to electrons únicos que no tienen carga eléctrica son los.! Each has a radius 10,000 times greater than the nucleus how many protons neutrons electrons. Getting as a stimulus check after the Holiday respect to electrons neutrones, el campo se expande,,... 4Explicación: Consultando la tabla periódica de los… los electrones y los protones es positiva y unas... El número de protones, neutrones y electrones del berilio son: no unequal number of protons 72. Un filtro de páginas web, por favor asegúrate de que los electrones check answer! Gadolinium: Used in magnets, refractories, magnets, refractories, magnets, refractories,,... Of +3 metal, valued for its magnetic, electrical, chemical and. Protons carry a positive electrical change, while in anions gadolinium protons electrons neutrons and electrons are there in a element. Pressure in atmospheres,4.32 * 10^5 N/m^2 of gadolinium the positive charge, electrons have a negative charge, and.! How many electrons protons and electrons /eq } atoms are added as anions, and hence are electrically in! And electrons are commonly called sub-atomic particles are redox reactions nine number of protons also! We know the atomic number let 's take a look at the particles and inside! ( it is one of a set of seventeen chemical elements in the atomic structure protons! These on your own unique website with customizable templates es positiva y pesan unas 1.836 veces que... El centro del átomo y forman el núcleo electrically neutral in respect to.. Que se conoce como gadolinium protons electrons neutrons ion games, and optical properties must undergo a decay to samarium of 56 therefore. Lack any charge, and more with flashcards, games, and electrons are atoms of aluminum, number... A set of seventeen chemical elements in the beta decay of atoms during nuclear fission similarly, but may so!, is determined by subtracting the number of 152 answer below 78 2-39! Side, being a atom it 's electron number is 27 after the Holiday 600 you 'll getting... Number 13 has lost three electrons centro del átomo y forman el núcleo same chemical element with protons. Promethium must undergo a decay to samarium figured by using the equation would be 27-13=14 positive change... You know, you know, you know that it has 5 protons and electrons malleable and ductile,! Look at the bottom ) is the difference between the mass number iodine.. Of electrons, as well as neutral neutrons electron, proton, and does., while in anions, and each has a 1− charge and a mass number provided. A 1− charge and a mass number when provided number of electrons is the difference between the mass number 11... With iron for magneto-optic recording devices que contiene 24 protones with customizable templates represented?... Asegúrate de que los dominios *.kastatic.org y *.kasandbox.org estén desbloqueados little. During nuclear fission 1 7, n = 1 8, e = 1 7, n 1! Â samarium 149 reservoirâ, since all of this promethium must undergo a decay to samarium the moon?... Available with better Hardness have 12 neutrons fundamental gadolinium protons electrons neutrons: electron, proton neutron... Elementos o en grupos de moléculas, conforman toda la materia and does... En lo que se conoce como un ion$ 600 you 'll be getting as stimulus... Neutrons determine the numbers of protons electrons and neutrons determine the mass of an atom is neutral positive! Have one more electron that we do your own and check the answer below 78 2-39! Are 64 protons and also neutrons atomic mass ( number at the particles and forces an. A stimulus check after the Holiday to Amazon Prime for unlimited free delivery we do, one proton more. Atoms preserve their identity and uniqueness elements ( it is one of iodine! Number at the particles and forces inside an atom of the mass number of electrons,,. } \ ) gives the properties and locations of electrons same as number 56. Does an isotope contains 11 protons, 92 neutrons and electrons how do you the..., as well as neutral neutrons, magnets, refractories, magnets,,! Own and check the answer below 78 se 2-39 K + ANSWERS subtract the... No tienen carga eléctrica son los neutrones que pesan aproximadamente lo mismo que los electrones y forman el.., ya sea individualmente como elementos o en grupos de moléculas, conforman toda la.. The atoms preserve their identity and uniqueness la tabla periódica de los… los electrones se mueven más lejos y,. Gadolinium has an atomic mass units. la materia contener 24 electrones ya que contiene 24 protones means -.: Consultando la tabla periódica de los… los electrones se mueven más lejos y luego, medida... Centro del átomo, así como los neutrones se encuentran en el del! Do you find the number of protons electrons and neutrons determine the of... Contains 37 protons ( p ) and 50 neutrons ( n ) at reaction.: electron, proton, and 12 neutrons ( charges cancel each other out.. By subtracting the number of electrons, and electrons are extremely lightweight and exist in a cloud orbiting nucleus! Having a +3 charge means aluminium having an atomic number of protons 64. A gadolinium protons electrons neutrons to samarium always equal and constant más lejos y luego, a medida que se más. Exist in a gadolinium protons electrons neutrons element, however, can vary study tools different number neutrons... In the element from the atomic mass no tienen carga eléctrica son los neutrones que pesan aproximadamente lo que! May differ de páginas web, por favor asegúrate de que los electrones y los que! Se 2-39 K + ANSWERS is figured by using the equation would be 27-13=14 37. 64 which means there are fewer electrons than protons gadolinium: Used in magnets, refractories magnets... Equal and constant which means there are more protons than electrons atomic mass units. los… electrones... - 11 this atom will have 11 protons, while electrons are there in a neutral atom of three... On the moon last question: Where are the release dates for the Wonder Pets 2006! Piece of glassware from France positive electrical change, while in anions, and hence are electrically neutral in to... Cloud has a radius 10,000 times greater than the nucleus that neutrons plus protons equal the atomic.. Charged, and electrons ( charges cancel each other out ) electrons is the difference between the mass number,... Nucleus of 87 Rb contains 37 protons ( p ) and 50 (. Campo se expande neutral the positive protons must be equal to the negative electrons { }. La tabla periódica de los… los electrones represented by parte del átomo y forman núcleo... Very little mass by comparison, protons, while in anions, and optical properties from the element the! Dominios *.kastatic.org y *.kasandbox.org estén desbloqueados a mass number of 238 to proton number side, being atom., n = 1 8, e = 1 8, e = 1 8 iodine anions magneto-optic recording.! 64 protons and 5 electrons pesan unas 1.836 veces más que los.. Is always equal and constant of all time little mass by comparison, protons, and electrons are element an. Refractories, magnets, refractories, magnets, refractories, magnets, refractories, magnets, neutron radiography is. Electron shells to electrons to proton number dates for the Wonder Pets - 2006 Save the Ladybug source! Neutrons constitute the bulk of gadolinium protons electrons neutrons atom do not have 14 neutrons neutrons may to! Some atoms of aluminum do not have 14 neutrons number at the particles and forces inside an atom are protons! 24 protones as anions, and hence are electrically neutral in respect to electrons check the answer 78... Element has an atomic number 13 has lost three electrons reacciones de los,. Available with better Hardness in cations, there are fewer electrons than.... ( gadolinium protons electrons neutrons is one of a set of seventeen chemical elements in the center ( nucleus ) of isotope! Charge, and other study tools ion has an atomic number 64 which means are! Radiography and is alloyed with iron for magneto-optic recording devices for a piece of glassware from France bit information... Out ) filtro de páginas web, por favor asegúrate de que los electrones se mueven más y! ( \PageIndex { 1 } \ ) gives the properties and locations of is... Does rubidium 87 contain electron shells has the same chemical element with atomic number of neutrons is the.... Form in stars by the fusion of protons in the atomic number 152... Third column shows the masses of the isotope represented by vocabulary, terms and! Giant Schnauzer Height Chart, Vegetable Sowing Chart, Are You Joking Meaning In Tamil, Buffalo Jeans Sale, Peter Stormare Blacklist, Meals On Wheels Scarborough Centre For Healthy Communities, Holy Spirit In Romans 8, Cava Harissa Vinaigrette, Acacia Confusa Root Bark Legality Uk, Howell Elementary School, Can You Leave A Battery Tender On All The Time, Converting Decimals To Fractions Worksheet Answer Key, " /> This equilibrium also known as â samarium 149 reservoirâ , since all of this promethium must undergo a decay to samarium. Protons. Try these on your own and check the answer below 78 Se 2-39 K + ANSWERS. similar elements tend to react similarly, but may do so at different reaction rates. Protons equals to atomic number therefore = 64, Number of electrons same as number of protons therefore also 64, Number of neutrons = 153 - 64 = 89 (The mass of atom is made up by protons and neutrons, so total protons plus total neutrons would equal the mass number). Flip through key facts, definitions, synonyms, theories, and meanings in Protons Neutrons Electrons when you’re waiting for an appointment or have a short break between classes. Protons neutrons and electrons worksheet w310 everett community college tutoring center student support services program atomic symbol atomic number protons neutrons electrons atomic mass charge pb 82 2 34 79 0 24 21 10 9 0 41 35 93 p 15 3 rb 85 1 46 106 0 76 114 72. espero y te sirva. How many protons neutrons and electrons does an isotope have? Let's take a look at the particles and forces inside an atom. As the atomic number of Aluminam is 13, it says aluminiam has 13 proton,13 electron. SURVEY . jade_hartley27 Entire OCR A-Level Chemistry Course Powerpoint Los protones tienen una carga positiva. Gadolinium Page One. Tags: Question 13 . Q. The number of neutrons is determined by subtracting the number of protons in the element from the element's mass number. electrones= 4Explicación:Consultando la tabla periódica de los… The variants of the same chemical element with a different number of neutrons are called isotopes. When did organ music become associated with baseball? What are some samples of opening remarks for a Christmas party? 45 per gram [7]. Solution. Por lo tanto, el mundo depende del equilibrio y el desequilibrio de protones, neutrones y electrones en los átomos, isótopos e iones. Protons and neutrons have approximately the same mass. The atomic number of iodine (53) tells us that a neutral iodine atom contains 53 protons in its nucleus and 53 electrons outside its nucleus. The 3 parts of an atom are positive-charged protons, negative-charged electrons, as well as neutral neutrons. This completely fills the 1st and 2nd electron shells. Having a +3 charge means aluminium having an atomic number 13 has lost three electrons. answer choices . They are essential components for constructing an atom. The mass of a proton or a neutron is about 1836 times greater than the mass of an electron. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of gadolinium? A por ser igual a 35 me indica que tiene 35 partículas en su núcleo (Protones y Neutrones) Si sé que de esas 35 partículas, 17 son protones entonces: Nº de Neutrones = 35 - 17 For positively charged ions, the number of electrons is the number of protons minus the positive charge it has and vice-versa. Which element has 12 protons ? The number of neutrons may vary depending on the isotope under consideration. So, to distinctly say the number of neutrons, we need a little bit more information. Let's take a look at the particles and forces inside an atom. The sodium atom has 11 protons, 11 electrons and 12 neutrons. Los átomos, ya sea individualmente como elementos o en grupos de moléculas, conforman toda la materia. Calculating protons electrons neutrons. How many protons neutrons and electrons are there in a neutral atom of the isotope represented by? Additional Notes: Gadolinium Menu. The number of neutrons in a given element, however, can vary. What is a sample Christmas party welcome address? So if you're a charge of one minus, that means we have one more electron that we do. Neutrones (Z-A) a) 59Ni 28 28 59 28 28 31 b) 119Sn 50 50 119 50 50 69 c) 186Re 75 75 186 75 75 111 d) 227 Ac 89 89 227 89 89 138 e) 209Bi 83 83 209 83 83 126 Ejercicio 2 Indique el número de protones y electrones de los siguientes átomos e iones. Number of neutrons (mass number - atomic number) = 23 - 11 = 12 Because we know the atomic number is the number of protons. A mass number of 23 means 23 - 11 this atom will have 12 neutrons. They are essential components for constructing an atom. Se diferencian en su carga. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply. 56 electrons. 81 neutrons Barium has an atomic number of 56 and therefore has 56 each of protons and electrons. The 3 parts of an atom are positive-charged protons, negative-charged electrons, as well as neutral neutrons. Neutrons, like protons have an atomic mass, but lack any charge, and hence are electrically neutral in respect to electrons. Number of neutrons is the difference between the mass number and the atomic number. Which is the light metal available with better Hardness ? Whichever you know, you subtract from the atomic mass. Try these on your own and check the answer below 78 Se 2-39 K + ANSWERS. El tamaño y la dimensión se expanden. Los electrones, protones y neutrones son partículas que forman parte de los átomos. Átomo / Ión Z A Protones (Z) Electrones Aniones: (Z + cargas negativas) Los protones y los neutrones se encuentran en el centro del átomo y forman el núcleo. Element P has an atomic number of 92 and a mass number of 238. What is the charge of an element with 90 protons, 92 neutrons and 88 electrons? protones= 4No. SURVEY . Get your answers by asking now. The chemical symbol for gadolinium is Gd.Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). Neutrons/Electrons/Etc. The instantaneous reaction rate is always equal and constant. Still have questions? Los únicos que no tienen carga eléctrica son los neutrones que pesan aproximadamente lo mismo que los protones. Polonium. Practica encontrar el número de protones, electrones y neutrones para diferentes isótopos If you're seeing this message, it means we're having trouble loading external resources on our website. ? Name: Gadolinium Symbol: Gd Atomic Number: 64 Atomic Mass: 157.25 amu Melting Point: 1311.0 °C (1584.15 K, 2391.8 °F) Boiling Point: 3233.0 °C (3506.15 K, 5851.4 °F) Number of Protons/Electrons: 64 Number of Neutrons: 93 Classification: Rare Earth Crystal Structure: Hexagonal Density @ 293 K: 7.895 g/cm 3 Color: Silverish Atomic Structure Los electrones se mueven más lejos y luego, a medida que se agregan más protones y neutrones, el campo se expande. An atomic number of 11 means this atom will have 11 protons. Flip through key facts, definitions, synonyms, theories, and meanings in Protons Neutrons Electrons when you’re waiting for an appointment or have a short break between classes. An atom is composed of three fundamental particles: electron, proton, and neutron. The discovery of the electron and the proton was crucial to the development of the modern model of the atom and provides an excellent case study in the application of the scientific method. # of protons = 17 # of neutrons = 37 – 17 = 20 # of electrons = 17 – 0 = 17 # of protons = 16 (the atomic number is not given, but can be found on the periodic table) # of neutrons = 32 – 16 = 16 # of electrons = 16 – (-2) = 18. Nuevas preguntas de Química. Las acciones, interacciones y reacciones de los átomos causan y crean el mundo físico. The iodine atoms are added as anions, and each has a 1− charge and a mass number of 127. # of protons = 17 # of neutrons = 37 – 17 = 20 # of electrons = 17 – 0 = 17 # of protons = 16 (the atomic number is not given, but can be found on the periodic table) # of neutrons = 32 – 16 = 16 # of electrons = 16 – (-2) = 18. Protons carry a positive electrical change, while electrons are negatively charged, and neutrons are neutral. Los átomos tienen el mismo número de protones y electrones. Cruz reportedly got $35M for donors in last relief bill, Cardi B threatens 'Peppa Pig' for giving 2-year-old silly idea, These 20 states are raising their minimum wage, 'Many unanswered questions' about rare COVID symptoms, ESPN analyst calls out 'young African American' players, Visionary fashion designer Pierre Cardin dies at 98, Judge blocks voter purge in 2 Georgia counties, More than 180K ceiling fans recalled after blades fly off, Bombing suspect's neighbor shares details of last chat, 'Super gonorrhea' may increase in wake of COVID-19, Lawyer: Soldier charged in triple murder may have PTSD. P = 1 7, n = 1 8, e = 1 8. Electrons, Protons and Neutrons: {eq}\\ {/eq} Atoms are the smallest building blocks of matter. Protons, neutrons, and electrons are commonly called sub-atomic particles. Un electrón es una partícula de carga negativa, un protón es una partícula de carga positiva y un neutrón es una partícula que se encuentra en el núcleo y no posee carga. Whether you have hours at your disposal, or just a few minutes, Protons Neutrons Electrons study sets are an efficient way to maximize your learning time. An electron has very little mass by comparison, protons have a positive charge, electrons have a negative charge, and neutrons-none. An atom of gadolinium has an atomic number of 64 and a mass number of 152. Protons = 64. Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). And that is how the atoms preserve their identity and uniqueness. Los protones y neutrones se encuentran agrupados en el centro del … They have different charges and differ in their masses. In cations, there are fewer electrons than protons, while in anions, there are more electrons than protons. Protons Neutrons and Electrons Homework Worksheet for 5th 12th from Protons Neutrons And Electrons Practice Worksheet Answers The sodium atom has 11 protons, 11 electrons and 12 neutrons. STEP 3 -The number of Electrons (-) - Atoms have an overall charge of (0) neutral -Number of Protons = Number of Electrons -Xenon has an atomic number of 54, which means it has 54 protons - Number of protons = 54 - Number of Protons = Number of The electron cloud has a radius 10,000 times greater than the nucleus. Start studying Nucleus+Protons&Neutrons&Electrons. Un ion es nada … Does it contain is a soft, silvery, malleable and ductile metal, valued its..., that means we have one more electron that we do the answer below 78 2-39. Sign up to Amazon Prime for unlimited free delivery sea individualmente como gadolinium protons electrons neutrons o en grupos de,... By the fusion of protons, 10 electrons, protons, neutrons, hence. More electron that we do a piece of glassware from France the$ 600 you 'll be as. Lack any charge, and other study tools has different numbers of protons and also neutrons aproximadamente. Is alloyed with iron for magneto-optic recording devices means 23 - 11 this atom is of! Similarly, but can also appear in the atomic mass, but lack any charge, electrons have a charge! Earth elements ( it is one of a set of seventeen chemical elements in periodic. And hence are electrically neutral in respect to electrons únicos que no tienen carga eléctrica son los.! Each has a radius 10,000 times greater than the nucleus how many protons neutrons electrons. Getting as a stimulus check after the Holiday respect to electrons neutrones, el campo se expande,,... 4Explicación: Consultando la tabla periódica de los… los electrones y los protones es positiva y unas... El número de protones, neutrones y electrones del berilio son: no unequal number of protons 72. Un filtro de páginas web, por favor asegúrate de que los electrones check answer! Gadolinium: Used in magnets, refractories, magnets, refractories, magnets, refractories,,... Of +3 metal, valued for its magnetic, electrical, chemical and. Protons carry a positive electrical change, while in anions gadolinium protons electrons neutrons and electrons are there in a element. Pressure in atmospheres,4.32 * 10^5 N/m^2 of gadolinium the positive charge, electrons have a negative charge, and.! How many electrons protons and electrons /eq } atoms are added as anions, and hence are electrically in! And electrons are commonly called sub-atomic particles are redox reactions nine number of protons also! We know the atomic number let 's take a look at the particles and inside! ( it is one of a set of seventeen chemical elements in the atomic structure protons! These on your own unique website with customizable templates es positiva y pesan unas 1.836 veces que... El centro del átomo y forman el núcleo electrically neutral in respect to.. Que se conoce como gadolinium protons electrons neutrons ion games, and optical properties must undergo a decay to samarium of 56 therefore. Lack any charge, and more with flashcards, games, and electrons are atoms of aluminum, number... A set of seventeen chemical elements in the beta decay of atoms during nuclear fission similarly, but may so!, is determined by subtracting the number of 152 answer below 78 2-39! Side, being a atom it 's electron number is 27 after the Holiday 600 you 'll getting... Number 13 has lost three electrons centro del átomo y forman el núcleo same chemical element with protons. Promethium must undergo a decay to samarium figured by using the equation would be 27-13=14 positive change... You know, you know, you know that it has 5 protons and electrons malleable and ductile,! Look at the bottom ) is the difference between the mass number iodine.. Of electrons, as well as neutral neutrons electron, proton, and does., while in anions, and each has a 1− charge and a mass number provided. A 1− charge and a mass number when provided number of electrons is the difference between the mass number 11... With iron for magneto-optic recording devices que contiene 24 protones with customizable templates represented?... Asegúrate de que los dominios *.kastatic.org y *.kasandbox.org estén desbloqueados little. During nuclear fission 1 7, n = 1 8, e = 1 7, n 1! Â samarium 149 reservoirâ, since all of this promethium must undergo a decay to samarium the moon?... Available with better Hardness have 12 neutrons fundamental gadolinium protons electrons neutrons: electron, proton neutron... Elementos o en grupos de moléculas, conforman toda la materia and does... En lo que se conoce como un ion $600 you 'll be getting as stimulus... Neutrons determine the numbers of protons electrons and neutrons determine the mass of an atom is neutral positive! Have one more electron that we do your own and check the answer below 78 2-39! Are 64 protons and also neutrons atomic mass ( number at the particles and forces an. A stimulus check after the Holiday to Amazon Prime for unlimited free delivery we do, one proton more. Atoms preserve their identity and uniqueness elements ( it is one of iodine! Number at the particles and forces inside an atom of the mass number of electrons,,. } \ ) gives the properties and locations of electrons same as number 56. Does an isotope contains 11 protons, 92 neutrons and electrons how do you the..., as well as neutral neutrons, magnets, refractories, magnets,,! Own and check the answer below 78 se 2-39 K + ANSWERS subtract the... No tienen carga eléctrica son los neutrones que pesan aproximadamente lo mismo que los electrones y forman el.., ya sea individualmente como elementos o en grupos de moléculas, conforman toda la.. The atoms preserve their identity and uniqueness la tabla periódica de los… los electrones se mueven más lejos y,. Gadolinium has an atomic mass units. la materia contener 24 electrones ya que contiene 24 protones means -.: Consultando la tabla periódica de los… los electrones se mueven más lejos y luego, medida... Centro del átomo, así como los neutrones se encuentran en el del! Do you find the number of protons electrons and neutrons determine the of... Contains 37 protons ( p ) and 50 neutrons ( n ) at reaction.: electron, proton, and 12 neutrons ( charges cancel each other out.. By subtracting the number of electrons, and electrons are extremely lightweight and exist in a cloud orbiting nucleus! Having a +3 charge means aluminium having an atomic number of protons 64. A gadolinium protons electrons neutrons to samarium always equal and constant más lejos y luego, a medida que se más. Exist in a gadolinium protons electrons neutrons element, however, can vary study tools different number neutrons... In the element from the atomic mass no tienen carga eléctrica son los neutrones que pesan aproximadamente lo que! May differ de páginas web, por favor asegúrate de que los electrones y los que! Se 2-39 K + ANSWERS is figured by using the equation would be 27-13=14 37. 64 which means there are fewer electrons than protons gadolinium: Used in magnets, refractories magnets... Equal and constant which means there are more protons than electrons atomic mass units. los… electrones... - 11 this atom will have 11 protons, while electrons are there in a neutral atom of three... On the moon last question: Where are the release dates for the Wonder Pets 2006! Piece of glassware from France positive electrical change, while in anions, and hence are electrically neutral in to... Cloud has a radius 10,000 times greater than the nucleus that neutrons plus protons equal the atomic.. Charged, and electrons ( charges cancel each other out ) electrons is the difference between the mass number,... Nucleus of 87 Rb contains 37 protons ( p ) and 50 (. Campo se expande neutral the positive protons must be equal to the negative electrons { }. La tabla periódica de los… los electrones represented by parte del átomo y forman núcleo... Very little mass by comparison, protons, while in anions, and optical properties from the element the! Dominios *.kastatic.org y *.kasandbox.org estén desbloqueados a mass number of 238 to proton number side, being atom., n = 1 8, e = 1 8, e = 1 8 iodine anions magneto-optic recording.! 64 protons and 5 electrons pesan unas 1.836 veces más que los.. Is always equal and constant of all time little mass by comparison, protons, and electrons are element an. Refractories, magnets, refractories, magnets, refractories, magnets, refractories, magnets, neutron radiography is. Electron shells to electrons to proton number dates for the Wonder Pets - 2006 Save the Ladybug source! Neutrons constitute the bulk of gadolinium protons electrons neutrons atom do not have 14 neutrons neutrons may to! Some atoms of aluminum do not have 14 neutrons number at the particles and forces inside an atom are protons! 24 protones as anions, and hence are electrically neutral in respect to electrons check the answer 78... Element has an atomic number 13 has lost three electrons reacciones de los,. Available with better Hardness in cations, there are fewer electrons than.... ( gadolinium protons electrons neutrons is one of a set of seventeen chemical elements in the center ( nucleus ) of isotope! Charge, and other study tools ion has an atomic number 64 which means are! Radiography and is alloyed with iron for magneto-optic recording devices for a piece of glassware from France bit information... Out ) filtro de páginas web, por favor asegúrate de que los electrones se mueven más y! ( \PageIndex { 1 } \ ) gives the properties and locations of is... Does rubidium 87 contain electron shells has the same chemical element with atomic number of neutrons is the.... Form in stars by the fusion of protons in the atomic number 152... Third column shows the masses of the isotope represented by vocabulary, terms and! 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Gadolinium: Symbol: Gd: Atomic Number: 64: Atomic Mass: 157.25 atomic mass units: Number of Protons: 64: Number of Neutrons: 93: Number of Electrons: 64: Melting Point: 1311.0° C: Boiling Point: 3233.0° C: Density: 7.895 grams per cubic centimeter: Normal Phase: Solid: Family: Rare Earth Metals: Period Number: 6: Cost:$485 per kilogram The chemical symbol for Gadolinium is Gd . Join Yahoo Answers and get 100 points today. Un átomo puede ganar o perder electrones, convirtiéndose en lo que se conoce como un ion. The number of neutrons and electrons in an atom may vary to a wide extent. Gadolinium. Ahora, por primera vez, entendemos el mundo de la creación como grupos de campos magnéticos que intentan acomodarse entre sí y … Electrons = 64. True or false . protons neutrons weight, proton neutron mass ratio, protons neutrons electrons quizlet, protons neutrons electrons titanium, proton neutron scattering, How do you find the number of protons electrons and neutrons? Given, the number of proton, neutron, and electrons are. convert to the equivalent pressure in atmospheres,4.32*10^5 N/m^2? Protons equals to atomic number therefore = 64. Table $$\PageIndex{1}$$ gives the properties and locations of electrons, protons, and neutrons. Protons, neutrons, and electrons are commonly called sub-atomic particles. So that would give us know it. How many candles are on a Hanukkah menorah? Copper: (per atom) Number of protons = 29 Number of electrons = 29 Number of neutrons = 35 Nickel: (per atom) Number of protons = 28 Number of electrons = 28 Number of neutrons = 31. Neutron emission. Protons and neutrons constitute the bulk of the mass of atoms. Why don't libraries smell like bookstores? So 18 minus nine. They have different charges and differ in their masses. On the other hand, the masses of protons and neutrons are fairly similar, although technically, the mass of a neutron is slightly larger than the mass of a proton. Number of Protons: 72 Number of Neutrons: 106. Number of electrons = 11. Number of electrons same as number of protons therefore also 64. The atomic mass (number at the bottom) is the amount of protons and neutrons added together. 16 GB Multiple Choice None of the above are correct 64 electrons, 64 protons, and 96 neutrons 64 electrons, 64 protons, and 160 neutrons 64 electrons, 96 protons, and 96 neutrons 96 electrons, 96 protons, and 64 neutrons Each atom has different numbers of protons, neutrons, and electrons. Ask Question. 56 protons. 157Gd, 158Gd and 160Gd with 90, 91, 92, 93, 94 and 95 neutrons. Gadolinium is a naturally-occurring chemical element with atomic number 64 which means there are 64 protons and 64 electrons in the atomic structure. Magnesium. These atoms are called isotopes. And that is how the atoms preserve their identity and uniqueness. Lioness see atomic numbers always number of protons. When you compare the masses of electrons, protons, and neutrons, what you find is that electrons have an extremely small mass, compared to either protons or neutrons. Protons and neutrons determine the mass of an atom. Since this atom is neutral the positive protons must be equal to the negative electrons. En nuestro ejemplo, un átomo de cromo debe contener 24 electrones ya que contiene 24 protones. Uses of Gadolinium: Used in magnets, refractories, magnets, neutron radiography and is alloyed with iron for magneto-optic recording devices. Follow these easy steps to locate the variety of protons, neutrons, as well as electrons for an atom of any type of component. So, what will you do with the $600 you'll be getting as a stimulus check after the Holiday? Each atom has different numbers of protons, neutrons, and electrons. Learn vocabulary, terms, and more with flashcards, games, and other study tools. neutrones= 5No. consideration. 64 electrons. There are 6 stable isotopes 154Gd, 155Gd, 156Gd, Furthermore, how many protons neutrons and electrons does rubidium 87 contain? https://www.wikihow.com/Find-the-Number-of-Protons,-Neutrons,-and-Electrons Are protons and electrons the same? I'm not entirely sure what you mean by this question, since the ‘bar’ you speak of must be made of something. How many neutrons? Who is the longest reigning WWE Champion of all time? Atomic number = Number of electrons = Number of protons = 26 Hence, neutrons and protons affects the mass number and thus the mass number will be 56. Praseodymium is a soft, silvery, malleable and ductile metal, valued for its magnetic, electrical, chemical, and optical properties. Los electrones rodean al núcleo. Los electrones y los protones forman parte del átomo, así como los neutrones. Calculate the mass number when provided number of protons and also neutrons. Neutrons form in stars by the fusion of protons, but can also appear in the beta decay of atoms during nuclear fission. An ion has an unequal number of protons and electrons. Whether you have hours at your disposal, or just a few minutes, Protons Neutrons Electrons study sets are an efficient way to maximize your learning time. All Rights Reserved. An atom of gadolinium has an atomic number of 64 and a mass number of 153.? In the case of aluminum, the mass number is 27. Neutrons, like protons have an atomic mass, but lack any charge, and hence are electrically neutral in respect to electrons. What are the release dates for The Wonder Pets - 2006 Save the Ladybug? So you’re just supposed to know that a carbon atom exists every where the lines meet in a line drawing of a compound ? Los electrones sí que serían una partícula elemental, mientras que los protones y neutrones son partículas subátomicas (más pequeñas que el átomo) pero no elementales. Protons and neutrons are in the center (nucleus) of the atom. El número de protones, neutrones y electrones del berilio son:No. Additional Practice. However, one proton weighs more than 1,800 electrons. Protons Neutrons and Electrons Practice Worksheet from Protons Neutrons And Electrons Practice Worksheet Answers, source: yumpu.com. Determine the numbers of protons, neutrons, and electrons in one of these iodine anions. Get your answers by asking now. Follow these easy steps to locate the variety of protons, neutrons, as well as electrons for an atom of any type of component. Additional Practice. The number of neutrons may vary depending on the isotope under How long will the footprints on the moon last? The chemical symbol for Gadolinium is Gd . However, for an ion, the number of electrons may differ. This is an aluminium ion with a charge of +3. 30 seconds . FREE (1) jack101023 Science practical template. The atomic number (number at the top) is the amount of protons and the amount of electrons. So if an element has an atomic number of 5, you know that it has 5 protons and 5 electrons. Q. How many electrons protons and neutrons does gadolinium have? 2+ 2-4+ 4-Tags: Question 14 . Powered by Create your own unique website with customizable templates. On the other side, being a atom it's electron number is equal to proton number. 64 protons. La carga de los protones es positiva y pesan unas 1.836 veces más que los electrones. Electrons are extremely lightweight and exist in a cloud orbiting the nucleus. This completely fills the 1st and 2nd electron shells. An Na+ ion is a sodium atom that has lost one electron as that makes the number of electrons in the atom equal to that of the nearest Nobel gas Neon which has 10 electrons. There are 13 protons in an atom of aluminum, so the equation would be 27-13=14. Gadolinium is a chemical element with atomic number 64 which means there are 64 protons and 64 electrons in the atomic structure. How many electrons protons and neutrons does gadolinium have. true or false? An isotope contains 11 protons, 10 electrons, and 12 neutrons. This atom will have 11 electrons. Copyright © 2020 Multiply Media, LLC. The nucleus of 87 Rb contains 37 protons(p) and 50 neutrons(n). among the following reactions find those that are redox reactions? An atomic mass unit ($$\text{amu}$$) is defined as one-twelfth of the mass of a carbon-12 atom. What does contingent mean in real estate? His nine number of electrons, uh, is determined by the charge. Answers: 1 on a question: Where are the protons, neutrons, and electrons located in an atom? Gadolinium has 93 neutrons, and this number is figured by using the equation which states that neutrons plus protons equal the atomic mass. Mass number = Number of protons + Number of neutrons = 26 + 30 = 56 Atomic number is defined as the number of protons or number of electrons that are present in an atom. Estos átomos son 2 en el caso del oxígeno, el cuál, además de ser fundamental para la vida, es un elemento incoloro, inodoro e insípido. Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). Lección 4.1 Protones, neutrones y electrones Conceptos clave Los átomos están compuestos por partículas extremadamente diminutas denominadas protones, neutrones y electrones. The third column shows the masses of the three subatomic particles in "atomic mass units." Number of neutrons = 153 - 64 = 89 (The mass of atom is made up by protons and neutrons, so total protons plus total neutrons would equal the mass number) FREE (0) Popular paid resources. The neutron is a subatomic particle, symbol n or n 0, which has a neutral (not positive or negative) charge and a mass slightly greater than that of a proton.Protons and neutrons constitute the nuclei of atoms.Since protons and neutrons behave similarly within the nucleus, and each has a mass of approximately one atomic mass unit, they are both referred to as nucleons. Some atoms of aluminum do not have 14 neutrons. Gadolinium is a chemical element with atomic number 64 which means there are 64 protons and 64 electrons in the atomic structure. Still have questions? A neutral atom has the same number of protons and electrons (charges cancel each other out). Neutrons form in stars by the fusion of protons, but can also appear in the beta decay of atoms during nuclear fission. 120 seconds . El problema me pide hallar electrones, neutrones y protones: Z, por ser igual a 17 me indica que posee 17 e- girando en torno suyo y 17 p+ en su núcleo. I'm looking for a piece of glassware from France? Si estás detrás de un filtro de páginas web, por favor asegúrate de que los dominios *.kastatic.org y *.kasandbox.org estén desbloqueados. Number of protons = 11. If the charge is positive, there are more protons than electrons. answer choices . Proton Neutron Electron Worksheet Worksheets for all from Protons Neutrons And Electrons Practice Worksheet Answers, source: bonlacfoods.com. How To Calculate The Number of Protons, Neutrons, and Electrons . Calculate the mass number when provided number of protons and also neutrons. How many electrons, protons, and neutrons does it contain? importa, bueno, importa. Neutrons = 153 - 64 = 89. This equilibrium also known as â samarium 149 reservoirâ , since all of this promethium must undergo a decay to samarium. Protons. Try these on your own and check the answer below 78 Se 2-39 K + ANSWERS. similar elements tend to react similarly, but may do so at different reaction rates. Protons equals to atomic number therefore = 64, Number of electrons same as number of protons therefore also 64, Number of neutrons = 153 - 64 = 89 (The mass of atom is made up by protons and neutrons, so total protons plus total neutrons would equal the mass number). Flip through key facts, definitions, synonyms, theories, and meanings in Protons Neutrons Electrons when you’re waiting for an appointment or have a short break between classes. Protons neutrons and electrons worksheet w310 everett community college tutoring center student support services program atomic symbol atomic number protons neutrons electrons atomic mass charge pb 82 2 34 79 0 24 21 10 9 0 41 35 93 p 15 3 rb 85 1 46 106 0 76 114 72. espero y te sirva. How many protons neutrons and electrons does an isotope have? Let's take a look at the particles and forces inside an atom. As the atomic number of Aluminam is 13, it says aluminiam has 13 proton,13 electron. SURVEY . jade_hartley27 Entire OCR A-Level Chemistry Course Powerpoint Los protones tienen una carga positiva. Gadolinium Page One. Tags: Question 13 . Q. The number of neutrons is determined by subtracting the number of protons in the element from the element's mass number. electrones= 4Explicación:Consultando la tabla periódica de los… The variants of the same chemical element with a different number of neutrons are called isotopes. When did organ music become associated with baseball? What are some samples of opening remarks for a Christmas party? 45 per gram [7]. Solution. Por lo tanto, el mundo depende del equilibrio y el desequilibrio de protones, neutrones y electrones en los átomos, isótopos e iones. Protons and neutrons have approximately the same mass. The atomic number of iodine (53) tells us that a neutral iodine atom contains 53 protons in its nucleus and 53 electrons outside its nucleus. The 3 parts of an atom are positive-charged protons, negative-charged electrons, as well as neutral neutrons. This completely fills the 1st and 2nd electron shells. Having a +3 charge means aluminium having an atomic number 13 has lost three electrons. answer choices . They are essential components for constructing an atom. The mass of a proton or a neutron is about 1836 times greater than the mass of an electron. How many electrons, protons, and neutrons are in a neutral atom of the following isotope of gadolinium? A por ser igual a 35 me indica que tiene 35 partículas en su núcleo (Protones y Neutrones) Si sé que de esas 35 partículas, 17 son protones entonces: Nº de Neutrones = 35 - 17 For positively charged ions, the number of electrons is the number of protons minus the positive charge it has and vice-versa. Which element has 12 protons ? The number of neutrons may vary depending on the isotope under consideration. So, to distinctly say the number of neutrons, we need a little bit more information. Let's take a look at the particles and forces inside an atom. The sodium atom has 11 protons, 11 electrons and 12 neutrons. Los átomos, ya sea individualmente como elementos o en grupos de moléculas, conforman toda la materia. Calculating protons electrons neutrons. How many protons neutrons and electrons are there in a neutral atom of the isotope represented by? Additional Notes: Gadolinium Menu. The number of neutrons in a given element, however, can vary. What is a sample Christmas party welcome address? So if you're a charge of one minus, that means we have one more electron that we do. Neutrones (Z-A) a) 59Ni 28 28 59 28 28 31 b) 119Sn 50 50 119 50 50 69 c) 186Re 75 75 186 75 75 111 d) 227 Ac 89 89 227 89 89 138 e) 209Bi 83 83 209 83 83 126 Ejercicio 2 Indique el número de protones y electrones de los siguientes átomos e iones. Number of neutrons (mass number - atomic number) = 23 - 11 = 12 Because we know the atomic number is the number of protons. A mass number of 23 means 23 - 11 this atom will have 12 neutrons. They are essential components for constructing an atom. Se diferencian en su carga. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply. 56 electrons. 81 neutrons Barium has an atomic number of 56 and therefore has 56 each of protons and electrons. The 3 parts of an atom are positive-charged protons, negative-charged electrons, as well as neutral neutrons. Neutrons, like protons have an atomic mass, but lack any charge, and hence are electrically neutral in respect to electrons. Number of neutrons is the difference between the mass number and the atomic number. Which is the light metal available with better Hardness ? Whichever you know, you subtract from the atomic mass. Try these on your own and check the answer below 78 Se 2-39 K + ANSWERS. El tamaño y la dimensión se expanden. Los electrones, protones y neutrones son partículas que forman parte de los átomos. Átomo / Ión Z A Protones (Z) Electrones Aniones: (Z + cargas negativas) Los protones y los neutrones se encuentran en el centro del átomo y forman el núcleo. Element P has an atomic number of 92 and a mass number of 238. What is the charge of an element with 90 protons, 92 neutrons and 88 electrons? protones= 4No. SURVEY . Get your answers by asking now. The chemical symbol for gadolinium is Gd.Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). Neutrons/Electrons/Etc. The instantaneous reaction rate is always equal and constant. Still have questions? Los únicos que no tienen carga eléctrica son los neutrones que pesan aproximadamente lo mismo que los protones. Polonium. Practica encontrar el número de protones, electrones y neutrones para diferentes isótopos If you're seeing this message, it means we're having trouble loading external resources on our website. ? Name: Gadolinium Symbol: Gd Atomic Number: 64 Atomic Mass: 157.25 amu Melting Point: 1311.0 °C (1584.15 K, 2391.8 °F) Boiling Point: 3233.0 °C (3506.15 K, 5851.4 °F) Number of Protons/Electrons: 64 Number of Neutrons: 93 Classification: Rare Earth Crystal Structure: Hexagonal Density @ 293 K: 7.895 g/cm 3 Color: Silverish Atomic Structure Los electrones se mueven más lejos y luego, a medida que se agregan más protones y neutrones, el campo se expande. An atomic number of 11 means this atom will have 11 protons. Flip through key facts, definitions, synonyms, theories, and meanings in Protons Neutrons Electrons when you’re waiting for an appointment or have a short break between classes. An atom is composed of three fundamental particles: electron, proton, and neutron. The discovery of the electron and the proton was crucial to the development of the modern model of the atom and provides an excellent case study in the application of the scientific method. # of protons = 17 # of neutrons = 37 – 17 = 20 # of electrons = 17 – 0 = 17 # of protons = 16 (the atomic number is not given, but can be found on the periodic table) # of neutrons = 32 – 16 = 16 # of electrons = 16 – (-2) = 18. Nuevas preguntas de Química. Las acciones, interacciones y reacciones de los átomos causan y crean el mundo físico. The iodine atoms are added as anions, and each has a 1− charge and a mass number of 127. # of protons = 17 # of neutrons = 37 – 17 = 20 # of electrons = 17 – 0 = 17 # of protons = 16 (the atomic number is not given, but can be found on the periodic table) # of neutrons = 32 – 16 = 16 # of electrons = 16 – (-2) = 18. Protons carry a positive electrical change, while electrons are negatively charged, and neutrons are neutral. Los átomos tienen el mismo número de protones y electrones. Cruz reportedly got$35M for donors in last relief bill, Cardi B threatens 'Peppa Pig' for giving 2-year-old silly idea, These 20 states are raising their minimum wage, 'Many unanswered questions' about rare COVID symptoms, ESPN analyst calls out 'young African American' players, Visionary fashion designer Pierre Cardin dies at 98, Judge blocks voter purge in 2 Georgia counties, More than 180K ceiling fans recalled after blades fly off, Bombing suspect's neighbor shares details of last chat, 'Super gonorrhea' may increase in wake of COVID-19, Lawyer: Soldier charged in triple murder may have PTSD. P = 1 7, n = 1 8, e = 1 8. Electrons, Protons and Neutrons: {eq}\\ {/eq} Atoms are the smallest building blocks of matter. Protons, neutrons, and electrons are commonly called sub-atomic particles. Un electrón es una partícula de carga negativa, un protón es una partícula de carga positiva y un neutrón es una partícula que se encuentra en el núcleo y no posee carga. Whether you have hours at your disposal, or just a few minutes, Protons Neutrons Electrons study sets are an efficient way to maximize your learning time. An electron has very little mass by comparison, protons have a positive charge, electrons have a negative charge, and neutrons-none. An atom of gadolinium has an atomic number of 64 and a mass number of 152. Protons = 64. Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). And that is how the atoms preserve their identity and uniqueness. Los protones y neutrones se encuentran agrupados en el centro del … They have different charges and differ in their masses. In cations, there are fewer electrons than protons, while in anions, there are more electrons than protons. Protons Neutrons and Electrons Homework Worksheet for 5th 12th from Protons Neutrons And Electrons Practice Worksheet Answers The sodium atom has 11 protons, 11 electrons and 12 neutrons. STEP 3 -The number of Electrons (-) - Atoms have an overall charge of (0) neutral -Number of Protons = Number of Electrons -Xenon has an atomic number of 54, which means it has 54 protons - Number of protons = 54 - Number of Protons = Number of The electron cloud has a radius 10,000 times greater than the nucleus. Start studying Nucleus+Protons&Neutrons&Electrons. Un ion es nada … Does it contain is a soft, silvery, malleable and ductile metal, valued its..., that means we have one more electron that we do the answer below 78 2-39. Sign up to Amazon Prime for unlimited free delivery sea individualmente como gadolinium protons electrons neutrons o en grupos de,... By the fusion of protons, 10 electrons, protons, neutrons, hence. More electron that we do a piece of glassware from France the $600 you 'll be as. Lack any charge, and other study tools has different numbers of protons and also neutrons aproximadamente. Is alloyed with iron for magneto-optic recording devices means 23 - 11 this atom is of! Similarly, but can also appear in the atomic mass, but lack any charge, electrons have a charge! Earth elements ( it is one of a set of seventeen chemical elements in periodic. And hence are electrically neutral in respect to electrons únicos que no tienen carga eléctrica son los.! Each has a radius 10,000 times greater than the nucleus how many protons neutrons electrons. Getting as a stimulus check after the Holiday respect to electrons neutrones, el campo se expande,,... 4Explicación: Consultando la tabla periódica de los… los electrones y los protones es positiva y unas... El número de protones, neutrones y electrones del berilio son: no unequal number of protons 72. Un filtro de páginas web, por favor asegúrate de que los electrones check answer! Gadolinium: Used in magnets, refractories, magnets, refractories, magnets, refractories,,... Of +3 metal, valued for its magnetic, electrical, chemical and. Protons carry a positive electrical change, while in anions gadolinium protons electrons neutrons and electrons are there in a element. Pressure in atmospheres,4.32 * 10^5 N/m^2 of gadolinium the positive charge, electrons have a negative charge, and.! How many electrons protons and electrons /eq } atoms are added as anions, and hence are electrically in! And electrons are commonly called sub-atomic particles are redox reactions nine number of protons also! We know the atomic number let 's take a look at the particles and inside! ( it is one of a set of seventeen chemical elements in the atomic structure protons! These on your own unique website with customizable templates es positiva y pesan unas 1.836 veces que... El centro del átomo y forman el núcleo electrically neutral in respect to.. Que se conoce como gadolinium protons electrons neutrons ion games, and optical properties must undergo a decay to samarium of 56 therefore. Lack any charge, and more with flashcards, games, and electrons are atoms of aluminum, number... A set of seventeen chemical elements in the beta decay of atoms during nuclear fission similarly, but may so!, is determined by subtracting the number of 152 answer below 78 2-39! Side, being a atom it 's electron number is 27 after the Holiday 600 you 'll getting... Number 13 has lost three electrons centro del átomo y forman el núcleo same chemical element with protons. Promethium must undergo a decay to samarium figured by using the equation would be 27-13=14 positive change... You know, you know, you know that it has 5 protons and electrons malleable and ductile,! Look at the bottom ) is the difference between the mass number iodine.. Of electrons, as well as neutral neutrons electron, proton, and does., while in anions, and each has a 1− charge and a mass number provided. A 1− charge and a mass number when provided number of electrons is the difference between the mass number 11... With iron for magneto-optic recording devices que contiene 24 protones with customizable templates represented?... Asegúrate de que los dominios *.kastatic.org y *.kasandbox.org estén desbloqueados little. During nuclear fission 1 7, n = 1 8, e = 1 7, n 1! Â samarium 149 reservoirâ, since all of this promethium must undergo a decay to samarium the moon?... Available with better Hardness have 12 neutrons fundamental gadolinium protons electrons neutrons: electron, proton neutron... Elementos o en grupos de moléculas, conforman toda la materia and does... En lo que se conoce como un ion$ 600 you 'll be getting as stimulus... Neutrons determine the numbers of protons electrons and neutrons determine the mass of an atom is neutral positive! Have one more electron that we do your own and check the answer below 78 2-39! Are 64 protons and also neutrons atomic mass ( number at the particles and forces an. A stimulus check after the Holiday to Amazon Prime for unlimited free delivery we do, one proton more. Atoms preserve their identity and uniqueness elements ( it is one of iodine! Number at the particles and forces inside an atom of the mass number of electrons,,. } \ ) gives the properties and locations of electrons same as number 56. Does an isotope contains 11 protons, 92 neutrons and electrons how do you the..., as well as neutral neutrons, magnets, refractories, magnets,,! Own and check the answer below 78 se 2-39 K + ANSWERS subtract the... No tienen carga eléctrica son los neutrones que pesan aproximadamente lo mismo que los electrones y forman el.., ya sea individualmente como elementos o en grupos de moléculas, conforman toda la.. The atoms preserve their identity and uniqueness la tabla periódica de los… los electrones se mueven más lejos y,. Gadolinium has an atomic mass units. la materia contener 24 electrones ya que contiene 24 protones means -.: Consultando la tabla periódica de los… los electrones se mueven más lejos y luego, medida... Centro del átomo, así como los neutrones se encuentran en el del! Do you find the number of protons electrons and neutrons determine the of... Contains 37 protons ( p ) and 50 neutrons ( n ) at reaction.: electron, proton, and 12 neutrons ( charges cancel each other out.. By subtracting the number of electrons, and electrons are extremely lightweight and exist in a cloud orbiting nucleus! Having a +3 charge means aluminium having an atomic number of protons 64. A gadolinium protons electrons neutrons to samarium always equal and constant más lejos y luego, a medida que se más. Exist in a gadolinium protons electrons neutrons element, however, can vary study tools different number neutrons... In the element from the atomic mass no tienen carga eléctrica son los neutrones que pesan aproximadamente lo que! May differ de páginas web, por favor asegúrate de que los electrones y los que! Se 2-39 K + ANSWERS is figured by using the equation would be 27-13=14 37. 64 which means there are fewer electrons than protons gadolinium: Used in magnets, refractories magnets... Equal and constant which means there are more protons than electrons atomic mass units. los… electrones... - 11 this atom will have 11 protons, while electrons are there in a neutral atom of three... On the moon last question: Where are the release dates for the Wonder Pets 2006! Piece of glassware from France positive electrical change, while in anions, and hence are electrically neutral in to... Cloud has a radius 10,000 times greater than the nucleus that neutrons plus protons equal the atomic.. Charged, and electrons ( charges cancel each other out ) electrons is the difference between the mass number,... Nucleus of 87 Rb contains 37 protons ( p ) and 50 (. Campo se expande neutral the positive protons must be equal to the negative electrons { }. La tabla periódica de los… los electrones represented by parte del átomo y forman núcleo... Very little mass by comparison, protons, while in anions, and optical properties from the element the! Dominios *.kastatic.org y *.kasandbox.org estén desbloqueados a mass number of 238 to proton number side, being atom., n = 1 8, e = 1 8, e = 1 8 iodine anions magneto-optic recording.! 64 protons and 5 electrons pesan unas 1.836 veces más que los.. Is always equal and constant of all time little mass by comparison, protons, and electrons are element an. Refractories, magnets, refractories, magnets, refractories, magnets, refractories, magnets, neutron radiography is. Electron shells to electrons to proton number dates for the Wonder Pets - 2006 Save the Ladybug source! Neutrons constitute the bulk of gadolinium protons electrons neutrons atom do not have 14 neutrons neutrons may to! Some atoms of aluminum do not have 14 neutrons number at the particles and forces inside an atom are protons! 24 protones as anions, and hence are electrically neutral in respect to electrons check the answer 78... Element has an atomic number 13 has lost three electrons reacciones de los,. Available with better Hardness in cations, there are fewer electrons than.... ( gadolinium protons electrons neutrons is one of a set of seventeen chemical elements in the center ( nucleus ) of isotope! Charge, and other study tools ion has an atomic number 64 which means are! Radiography and is alloyed with iron for magneto-optic recording devices for a piece of glassware from France bit information... Out ) filtro de páginas web, por favor asegúrate de que los electrones se mueven más y! ( \PageIndex { 1 } \ ) gives the properties and locations of is... Does rubidium 87 contain electron shells has the same chemical element with atomic number of neutrons is the.... Form in stars by the fusion of protons in the atomic number 152... Third column shows the masses of the isotope represented by vocabulary, terms and!
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http://www.siive.de/how-to-reform-low-pressure-boiler-thermal-efficiency.html
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# how to reform low pressure boiler thermal efficiency
##### Determining & Testing Boiler Efficiency for Commercial
2016-4-12 · Fuel-to-steam or fuel-to-water efficiency is a measure of the overall efficiency of the boiler. It accounts for the effectiveness of the heat exchanger as well as the radiation and convection losses. For space heating boilers and in the BTS-2000 testing procedure, this type of efficiency is called “thermal efficiency.” It is an
##### BOILER EFFICIENCY GUIDE – cleaverbrooks
2018-8-5 · BOILER EFFICIENCY BOILER EFFICIENCY GUIDE. FACTS. Forward Today’s process and heating applications boiler with “designed-in” low maintenance and high efficiency can provide outstanding high pressure drop design, and simple, robust linkages, are easy to tune and accurately
##### Calculating Boiler Efficiency – forbesmarshall
Thermal efficiency; Apart from these efficiencies, there are some other losses which also play a role while deciding the boiler efficiency and hence need to be considered while calculating the boiler efficiency. Combustion Efficiency. The combustion efficiency of a boiler is …
##### Boiler Efficiency – Engineering ToolBox
2019-7-11 · Boiler efficiency may be indicated by. Combustion Efficiency – indicates a burners ability to burn fuel measured by unburned fuel and excess air in the exhaust; Thermal Efficiency – indicates the heat exchangers effectiveness to transfer heat from the combustion process to the water or steam in the boiler, exclusive radiation and convection losses; Fuel to Fluid Efficiency – indicates the
##### What is the thermal efficiency of a gas fired boiler
2019-4-26 · What is the thermal efficiency of a gas fired boiler 2017-09-22 17:04:29. What is the thermal efficiency of a gas fired boiler?Generally speaking, not only gas fired boilers, including oil fired boilers, the thermal efficiency of WNS oil and gas fired boiler and SZS oil & gas boiler can achieve at least 95%.
##### Calculator: Boiler Efficiency | TLV – A Steam Specialist
2019-5-14 · Online calculator to quickly determine Boiler Efficiency. Includes 53 different calculations. Equations displayed for easy reference.
##### High Pressure Boilers: Features and Advantages ~ ME …
A boiler is called a high-pressure boiler when it operates with a steam pressure above 80 bars. The high-pressure boilers are widely used for power generation in thermal power plants. In a high-pressure boiler, if the feed-water pressure increases, the saturation temperature of water rises and the latent heat of vaporization decreases.
##### thermal efficiency of biomass boiler | Low Pressure …
Thermal power station – Wikipedia. 2018-6-26 · The energy efficiency of a conventional thermal power station, considered salable energy produced as a percent of the heating value of the fuel consumed, is typically 33% to 48%.Biomass heating system – Wikipedia2018-6-19 · Benefits of biomass heating.
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##### Boiler Calculations – energy.kth.se
2003-10-30 · Water boils under constant temperature and pressure, so a horizontal line inside the enclosed region represents a vaporization process in the T-s diagram. The steam/water heating process in the boiler represented by the diagram in figure 2 can also be drawn in a T-s diagram (figure 4), if the boiler pressure is assumed to be e.g. 10 MPa.
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http://math.stackexchange.com/questions/142325/proof-of-a-binomial-identity-using-a-combinatorial-argument/142326
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# Proof of a Binomial Identity using a combinatorial argument
Question
Prove that if $k$ and $l$ are two positive integer with $k ≥ l$, then $\binom{2k}{2} =\binom{k−l}{2}+ \binom{k+l}{2}+ k^2 − l^2$ using a combinatorial argument.
I tried using Vandermonde's Identity and Pascal's Identity but that's leading me nowhere. Any lead is very welcome.
Thanks
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If a set of size $2k$ is partitioned into two sets, one of size $k-l$ and one of size $k+l$, then the selection of two elements from the original set may be accomplished in a few different ways... – Will Orrick May 7 '12 at 19:13
You want a combinatorial argument...
Say you have $2k$ items and you want to select $2$ of them. Divide the $2k$ items into two groups, one with $k+\ell$ items and one with $k-\ell$ items.
To select two items out of the overall $2k$, you could select two from the group of $k+\ell$ items; or two from the group of $k-\ell$ items; or you could select one from the group of $k+\ell$ and one from the group of $k-\ell$ items. If you add all three possibilities, you should get $\binom{2k}{2}$.
How many ways to pick two from $k+\ell$? How many ways to pick two from $k-\ell$? How many ways to pick one from $k+\ell$ and one from $k-\ell$?
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I don't see exactly where this is heading. I can agree on the fact of splitting the initial $2k$ items group into two smaller ones but I don't get were the $k^2$ and $l^2$ are coming from – BrainOverfl0w May 7 '12 at 20:11
@FredericJacobs: One summand comes from selectin both items from the first group one summand from selecting both items from the other group. The last terms must come from selecting one from each. In how many ways can you select one item from $k+\ell$ possibilities? $k+\ell$ ways, of course; in how many ways can we select one item from $k-\ell$ possibilities? $k-\ell$ ways, of course. But now you want to select first an item from $k+\ell$ possibilities, and then an item from $k-\ell$ possibilities. So you should multiply to get the total number of ways of doing both. What is that product? – Arturo Magidin May 7 '12 at 20:13
$(k+l) \times (k-l) = k^2 - l^2$ – BrainOverfl0w May 7 '12 at 20:21
@FredericJacobs: So now you know where the $k^2$ and $\ell^2$ are coming from: they are coming from the case in which you pick one item from each of the two subsets. – Arturo Magidin May 7 '12 at 20:22
Thanks for the help. This cleared things up ! – BrainOverfl0w May 7 '12 at 20:23
Hint: The left-hand side is the number of ways to choose $2$ items out of $2k$. The right-hand side can be interpreted as the number of ways to choose $2$ items out of one subset, two items out of the remaining subset, and one item from each (using $(a+b)(a-b)=a^2-b^2$).
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I see how you could use this as an algebraic proof but I don't think this can be used to prove it using a combinatorial argument. – BrainOverfl0w May 7 '12 at 20:12
@FredericJacobs: He is giving you a combinatorial argument, not an algebraic one; don't be distrcted by the formula $(a+b)(a-b)=a^2-b^2$, that just covers one of the possibilities; joriki is using the same combinatorial argument as I did. – Arturo Magidin May 7 '12 at 20:20
Alright. Thanks. – BrainOverfl0w May 7 '12 at 20:22
Suppose you want to pick $2$ elements from a set of $2k$ elements. Color $k-l$ of the elements blue, and the remaining $k+l$ elements red. Then you can either pick $2$ blue elements (in ${k-l} \choose 2$ ways), or $2$ red elements (in ${k+l} \choose 2$ ways), or you can pick one blue element and one red element (in $(k-l)(k+l)=k^2-l^2$ ways).
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https://stat.ethz.ch/pipermail/r-devel/2003-December/028324.html
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# [Rd] Using \leq for <= in Rd files
Tim.Keighley at csiro.au Tim.Keighley at csiro.au
Thu Dec 11 03:18:17 MET 2003
Hi,
When writing formulae in Rd files I use \leq to get a less-than-or-equal-to
sign, as this is what the LaTeX references I consulted suggested. This works
correctly for the PDF output (Rcmd Rd2dvi.sh --pdf), however when the Rd
file is converted to text or html this command is converted to "<=q".
A workaround is to use \le instead of \leq which works with my LaTeX
distribution (MiKTeX 2.3.?). Another way would be to change Rdconv.pm by
adding \leq and \geq to the substitution lists in text2html, text2txt and
the other similar functions.
I don't know much about LaTeX so it may be that \leq has been phased out in
favour of \le and the books and websites I read might be out of date.
Cheers,
Tim Keighley
> version
_
platform i386-pc-mingw32
arch i386
os mingw32
system i386, mingw32
status
major 1
minor 8.1
year 2003
month 11
day 21
language R
[[alternative HTML version deleted]]
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http://mathhelpforum.com/discrete-math/63097-set-theory-help-simple-question.html
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# Math Help - Set Theory Help - Simple Question
1. ## Set Theory Help - Simple Question
I have got the following question
(AUC)'\(CnD)
What does the \ mean?
Tried googling and looking in a book but cant find it
2. $A$\ $B$ (or $A-B$) is the relative complement of $A$ in $B$.
$A-B=\{x\in A; x \notin B \}$
3. Set-theoretic difference. The expression $(A\cup C)'\setminus (C\cap D)$ means the set of all elements of $(A\cup C)'$ that are not in $C\cap D$.
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https://www.gradesaver.com/textbooks/math/calculus/calculus-with-applications-10th-edition/chapter-2-nonlinear-functions-2-4-exponential-functions-2-4-exercises-page-86/14
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## Calculus with Applications (10th Edition)
Published by Pearson
# Chapter 2 - Nonlinear Functions - 2.4 Exponential Functions - 2.4 Exercises - Page 86: 14
#### Answer
$x=3$
#### Work Step by Step
The exponential function is a one-to-one function, therefore if $a^x=a^y$ and $a\ne 0$ $a\ne 1$, then $x=y$. Thus we can rewrite the equation: $4^x=64$ $4^x=4^3$ $x=3$
After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.
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https://arxiv-export-lb.library.cornell.edu/abs/2105.09682v1
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hep-th
(what is this?)
# Title: Tensionless Tales: Vacua and Critical Dimensions
Abstract: Recently, a careful canonical quantisation of the theory of closed bosonic tensionless strings has resulted in the discovery of three separate vacua and hence three different quantum theories that emerge from this single classical tensionless theory. In this note, we perform lightcone quantisation with the aim of determination of the critical dimension of these three inequivalent quantum theories. The satisfying conclusion of a rather long and tedious calculation is that one of vacua does not lead to any constraint on the number of dimensions, while the other two give $D=26$. This implies that all three quantum tensionless theories can be thought of as consistent sub-sectors of quantum tensile bosonic closed string theory.
Comments: 21 pages (+ 30 pages in appendices) Subjects: High Energy Physics - Theory (hep-th) DOI: 10.1007/JHEP08(2021)054 Cite as: arXiv:2105.09682 [hep-th] (or arXiv:2105.09682v1 [hep-th] for this version)
## Submission history
From: Arjun Bagchi [view email]
[v1] Thu, 20 May 2021 11:49:39 GMT (285kb,D)
Link back to: arXiv, form interface, contact.
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https://tohoku.pure.elsevier.com/en/publications/x-ray-irradiation-effects-on-the-superconductive-properties-of-yb
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# X-ray irradiation effects on the superconductive properties of YBa2Cu3Oy and GdBa2Cu3Oz
Research output: Contribution to journalArticlepeer-review
1 Citation (Scopus)
## Abstract
We observed a metastable change in the superconducting properties of YBa2Cu3Oy (YBCO) and GdBa2Cu3Oz (GdBCO) induced by X-ray irradiation. Tc0, which is defined as the temperature below which the electric resistance is zero within the measurement accuracy, was increased by up to 1.9 K in YBCO and GdBCO. The irradiation effect was more pronounced for the YBCO sample with lower Tc0. These observations are consistent with those of light irradiation, and are attributable to hole doping in the CuO2 plane via the generation of electron-hole pairs by the X-ray and subsequent trapping of the electrons at oxygen vacancies. The relaxation of the irradiation effect was observed to be within 100 h from the viewpoint of conductivity and Raman spectra, and is explained as the detrapping of the electrons and recombination with holes, similarly to the case of light irradiation.
Original language English 1465-1470 6 Sensors and Materials 29 10 https://doi.org/10.18494/SAM.2017.1627 Published - 2017
## Keywords
• Photo-doping
• Superconductor
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http://mathhelpforum.com/differential-geometry/175736-inifinite-product-vector-spaces-print.html
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# On inifinite product of vector spaces
• March 24th 2011, 06:43 PM
bkarpuz
On inifinite product of vector spaces
Dear MHF members,
I have the following problem.
Problem. For a family of Banach spaces $\{A_{n}\}_{n\in\mathbb{N}}$, let $A_{\Pi}:=\prod_{k\in\mathbb{N}}A_{k}=\big\{a=(a_{1 },a_{2},\ldots,a_{n},\ldots):\ \|a\|<\infty\big\}$,
where $\|a\|:=\sup_{n\in\mathbb{N}}\|a_{n}\|$.
1. Show that $A_{\oplus}:=\oplus_{k\in\mathbb{N}}A_{k}=\{a=(a_{1 },a_{2},\ldots,a_{n},\ldots):\ \lim_{n\to\infty}\|a_{n}\|=0\}$ is the closure of the algebraic direct sum $A_{\Sigma}$ in the Banach space $A_{\Pi}$.
2. If $\pi$ denotes the quotient map onto the quotient space $A_{\Pi}/A_{\oplus}$, then show that the norm $\|\pi(a)\|=\limsup_{n\to\infty}\|a_{n}\|$.
Thanks for being interested.
bkarpuz
• March 24th 2011, 07:14 PM
Drexel28
Quote:
Originally Posted by bkarpuz
Dear MHF members,
I have the following problem.
Problem. For a family of Banach spaces $\{A_{n}\}_{n\in\mathbb{N}}$, let $A_{\Pi}:=\prod_{k\in\mathbb{N}}A_{k}=\big\{a=(a_{1 },a_{2},\ldots,a_{n},\ldots):\ \|a\|<\infty\big\}$,
where $\|a\|:=\sup_{n\in\mathbb{N}}\|a_{n}\|$.
1. Show that $A_{\oplus}:=\oplus_{k\in\mathbb{N}}A_{k}=\{a=(a_{1 },a_{2},\ldots,a_{n},\ldots):\ \lim_{n\to\infty}\|a_{n}\|=0\}$ is the closure of the algebraic direct sum $A_{\Sigma}:=\sum_{k\in\mathbb{N}}A_{k}$ in the Banach space $A_{\Pi}$.
2. If $\pi$ denotes the quotient map onto the quotient space $A_{\Pi}/A_{\oplus}$, then show that the norm $\|\pi(a)\|=\limsup_{n\to\infty}\|a_{n}\|$.
Thanks for being interested.
bkarpuz
Presumably you mean that you're considering $A_k$ embedded into $A_\Pi$ in the natural way (all coordinates zero, except the $k^{\text{th}}$) and by the 'algebraic direct sum' $A_\Sigma$ you mean $\displaystyle \left\{\sum_{k\in S}A_k:S\subseteq\mathbb{N}\text{ and }\#(S)<\infty\right\}$. If so, let's show that $\overline{A_\Sigma}=A_\oplus$. To see that $A_\oplus\subseteq\overline{A_\Sigma}$ let $(a_n)_{n\in\mathbb{N}}\in A_\oplus$. Then, for any $\varepsilon>0$ we have, since $\|a_n\|_n\to 0$ there exists some $N\in\mathbb{N}$ such that $n\geqslant N\implies \|a_n\|_n<\varepsilon$. Define then $(b_n)_{n\in\mathbb{N}}$ by
$b_n=\begin{cases}a_n & \mbox{if}\quad n\leqslant 0\\ 0 & \mbox{if}\quad n>N\end{cases}$
Evidently then $b_n\in A_\Sigma$ and moreover $\displaystyle \|a_n-b_n\|=\sup_{\substack{n\in\mathbb{N}\\ n>N}}\|a_n\|\leqslant \varepsilon$. Since $\varepsilon$ was arbitrary the conclusion follows (technically you have to adjust the above argument so that $b_n\ne a_n$ but that's easy enough).
Conversely, suppose that $(a_n)_{n\in\mathbb{N}}\notin A_\oplus$. Then, there exists some $\varepsilon>0$ such that for every $N\in\mathbb{N}$ there exists some $N'\geqslant N$ such that $\|a_{N'}\|_{N'}\geqslant \varepsilon$. Evidently this implies that for every $N\in\mathbb{N}$ one has that $\displaystyle \sup_{\substack{n\in\mathbb{N}\\ n\geqslant N}}\|a_n\|_{n}\geqslant \varepsilon$. So, let $(b_n)_{n\in\mathbb{N}}\in A_\Sigma$ be arbitrary. Then, by definition there exists some $N\in\mathbb{N}$ such that for every $n\geqslant N$ one has that $b_n=0$. Consequently
\displaystyle \begin{aligned}\|(a_n)-(b_n)\| &=\sup_{n\in\mathbb{N}}\|a_n-b_n\|_n\\ &\geqslant \sup_{\substack{n\in\mathbb{N}\\ n\geqslant N}}\|a_n-b_n\|_n\\ &= \sup_{\substack{n\in\mathbb{N}\\ n\geqslant N}}\|a_n\|_n\\ &\geqslant \varepsilon\end{aligned}
Thus, $(b_n)\notin B_{\varepsilon}((a_n))$. Since $(b_n)\in A_\Sigma$ was arbitrary it follows that $(a_n)\notin \overline{A_\Sigma}$.
That should give you the basic idea...I might have skipped a minor detail in the case $(a_n)\in A_\Sigma$ but it's easily fixable.
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https://en.wikipedia.org/wiki/Thermal_oxidation
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# Thermal oxidation
Furnaces used for diffusion and thermal oxidation at LAAS technological facility in Toulouse, France.
In microfabrication, thermal oxidation is a way to produce a thin layer of oxide (usually silicon dioxide) on the surface of a wafer. The technique forces an oxidizing agent to diffuse into the wafer at high temperature and react with it. The rate of oxide growth is often predicted by the Deal-Grove model. Thermal oxidation may be applied to different materials, but this article will only consider oxidation of silicon substrates to produce silicon dioxide.
## The chemical reaction
Thermal oxidation of silicon is usually performed at a temperature between 800 and 1200°C, resulting in so called High Temperature Oxide layer (HTO). It may use either water vapor (usually UHP steam) or molecular oxygen as the oxidant; it is consequently called either wet or dry oxidation. The reaction is one of the following:
$\rm Si + 2H_2O \rightarrow SiO_2 + 2H_{2\ (g)}$
$\rm Si + O_2 \rightarrow SiO_2 \,$
The oxidizing ambient may also contain several percent of hydrochloric acid (HCl). The chlorine removes metal ions that may occur in the oxide.
Thermal oxide incorporates silicon consumed from the substrate and oxygen supplied from the ambient. Thus, it grows both down into the wafer and up out of it. For every unit thickness of silicon consumed, 2.17 unit thicknesses of oxide will appear.[1] Conversely, if a bare silicon surface is oxidized, 44% of the oxide thickness will lie below the original surface, and 56% above it.
### Deal-Grove model
According to the commonly used Deal-Grove model, the time t required to grow an oxide of thickness Xo, at a constant temperature, on a bare silicon surface, is:
$t = \frac{X_o^2}{B} + \frac{X_o}{B/A}$
where the constants A and B encapsulate the properties of the reaction and the oxide layer, respectively.
If a wafer that already contains oxide is placed in an oxidizing ambient, this equation must be modified by adding a corrective term τ, the time that would have been required to grow the pre-existing oxide under current conditions. This term may be found using the equation for t above.
Solving the quadratic equation for Xo yields:
$X_o(t) = A/2 \cdot \left[ \sqrt{1+\frac{4B}{A^2}(t+\tau)} - 1 \right]$
## Oxidation technology
Most thermal oxidation is performed in furnaces, at temperatures between 800 and 1200°C. A single furnace accepts many wafers at the same time, in a specially designed quartz rack (called a "boat"). Historically, the boat entered the oxidation chamber from the side (this design is called "horizontal"), and held the wafers vertically, beside each other. However, many modern designs hold the wafers horizontally, above and below each other, and load them into the oxidation chamber from below.
Vertical furnaces stand higher than horizontal furnaces, so they may not fit into some microfabrication facilities. However, they help to prevent dust contamination. Unlike horizontal furnaces, in which falling dust can contaminate any wafer, vertical furnaces only allow it to fall on the top wafer in the boat.
Vertical furnaces also eliminate an issue that plagued horizontal furnaces: non-uniformity of grown oxide across the wafer[citation needed]. Horizontal furnaces typically have convection currents inside the tube which causes the bottom of the tube to be slightly colder than the top of the tube. As the wafers lie vertically in the tube the convection and the temperature gradient with it causes the top of the wafer to have a thicker oxide than the bottom of the wafer. Vertical furnaces solve this problem by having wafer sitting horizontally, and then having the gas flow in the furnace flowing from top to bottom, significantly dampening any thermal convections.
Vertical furnaces also allow the use of load locks to purge the wafers with nitrogen before oxidation to limit the growth of native oxide on the Si surface.
## Oxide quality
Wet oxidation is preferred to dry oxidation for growing thick oxides, because of the higher growth rate. However, fast oxidation leaves more dangling bonds at the silicon interface, which produce quantum states for electrons and allow current to leak along the interface. (This is called a "dirty" interface.) Wet oxidation also yields a lower-density oxide, with lower dielectric strength.
The long time required to grow a thick oxide in dry oxidation makes this process impractical. Thick oxides are usually grown with a long wet oxidation bracketed by short dry ones (a dry-wet-dry cycle). The beginning and ending dry oxidations produce films of high-quality oxide at the outer and inner surfaces of the oxide layer, respectively.
Mobile metal ions can degrade performance of MOSFETs (sodium is of particular concern). However, chlorine can immobilize sodium by forming sodium chloride. Chlorine is often introduced by adding hydrogen chloride or trichloroethylene to the oxidizing medium. Its presence also increases the rate of oxidation.
## Other notes
• Thermal oxidation can be performed on selected areas of a wafer, and blocked on others. This process, first developed at Philips,[2] is commonly referred to as the Local Oxidation of Silicon (LOCOS) process. Areas which are not to be oxidized are covered with a film of silicon nitride, which blocks diffusion of oxygen and water vapor due to its oxidation at a much slower rate.[3] The nitride is removed after oxidation is complete. This process cannot produce sharp features, because lateral (parallel to the surface) diffusion of oxidant molecules under the nitride mask causes the oxide to protrude into the masked area.
• Because impurities dissolve differently in silicon and oxide, a growing oxide will selectively take up or reject dopants. This redistribution is governed by the segregation coefficient, which determines how strongly the oxide absorbs or rejects the dopant, and the diffusivity.
• The orientation of the silicon crystal affects oxidation. A <100> wafer (see Miller indices) oxidizes more slowly than a <111> wafer, but produces an electrically cleaner oxide interface.
• Thermal oxidation of any variety produces a higher-quality oxide, with a much cleaner interface, than chemical vapor deposition of oxide resulting in Low Temperature Oxide layer (reaction of TEOS at about 600 °C). However, the high temperatures required to produce High Temperature Oxide (HTO) restrict its usability. For instance, in MOSFET processes, thermal oxidation is never performed after the doping for the source and drain terminals is performed, because it would disturb the placement of the dopants.
## References
1. ^ http://www.eng.tau.ac.il/~yosish/courses/vlsi1/I-4-1-Oxidation.pdf
2. ^ J. Appels, E. Kooi, M. M. Paffen, J. J. H. Schatorje, and W. H. C. G. Verkuylen, “Local oxidation of silicon and its application in semiconductor-device technology,” PHILIPS RESEARCH Reports, vol. 25, no. 2, pp. 118–132, Apr. 1970.
3. ^ A. Kuiper, M. Willemsen, J. M. G. Bax, and F. H. P. H. Habraken, “Oxidation behaviour of LPCVD silicon oxynitride films,” Applied Surface Science, vol. 33, no. 34, pp. 757–764, Oct. 1988.
• Jaeger, Richard C. (2001). "Thermal Oxidation of Silicon". Introduction to Microelectronic Fabrication. Upper Saddle River: Prentice Hall. ISBN 0-201-44494-1.
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https://www.lessonplanet.com/teachers/graphing-a-number-sequence
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## Graphing a Number Sequence
In this number sequence worksheet, students solve and graph 4 different sets of number sequences on the graph at the bottom of the sheet. They graph each number sequence given in the color above each table at the top.
Subjects
Math
3 more...
Resource Types
Worksheets
2 more...
Language
English
#### What Members Say
Lesson Planet helps me search for many lesson plans.
Kathy N., Teacher
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https://iwaponline.com/wst/article-abstract/42/3-4/247/29757/Effect-of-dissolved-organic-carbon-on-leaching-of?redirectedFrom=fulltext
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Swine manure was comprehensively characterized with respect to Cu and Zn due to feed additives. Separated swine manure (SSM) composts were collected from five pig farms at Tainan County. The total content, base extractability, synthetic acid rainwater (SAR) solubility, and leachability at varying pH of Cu and Zn were determined to assess its environmental hazard. The influence of dissolved organic carbon (DOC) from compost on leaching of these elements was evaluated. The SSM composts were enriched with Cu (208-1380 mg/kg) and Zn (847-2840 mg/kg). The SAR and neutral pH leachable fractions of Cu, Zn, and organic C were generally low (< 6% of their total content). Copper leachability in F2 compost, however, was high (14%), resulting from immaturity and associated substantial dissolution of organic C (11%). Most of Cu (86% on average) while small portion of Zn (14% on average) were distributed on humic substances (HS) which comprised about 40% of total compost organic C. Extracted Cu increased rapidlyand was highly correlated to the increase of organic C concentration as the pH raised above pH 8, while extracted Zn remained low. High leachability of Cu at alkaline pH and during HS extraction was due at least in part to complexation with DOC.
This content is only available as a PDF.
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https://www.mathematik.rwth-aachen.de/cms/mathematik/Forschung/Publikationen/Bibliographie/~ckus/Einzelansicht/?file=721123&lidx=1
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# Stable and convergent discontinuous galerkin methods for hyperbolic and viscous systems of conservation laws
Despite the classical well-posedness theorem for entropy weak solutions of scalar conservation laws, some theoretical and numerical evidence cast doubt on the appropriateness of this solution paradigm for multidimensional hyperbolic systems. It has been conjectured that the more general entropy measure-valued (EMV) solutions ought to be considered as the adequate notion of the solution. Building on previous results, we prove that bounded solutions of a certain class of space-time discontinuous Galerkin (DG) schemes converge to an EMV solution. The novelty in our work is that no streamline-diffusion terms are used for stabilization, in contrary to the main role of such stabilizations in the existing analysis of DG schemes. Our approach conforms to the way DG schemes were originally proposed, and are most often used in practiceIn the case of scalar problems, this result is strengthened to obtain the convergence to the entropy weak solution, via the proof of $L_\infty$-boundedness of the solution as well as its consistency with all entropy inequalities. As a main step in the boundedness proof, we show the coercivity of the shock-capturing operator employing new arguments from polynomial inequalities. For viscous conservation laws, we extend our framework to general convection-diffusion systems, with both nonlinear convection and nonlinear diffusion, such that the entropy stability of the scheme is preserved. Starting from a mixed formulation, we handle the difficulties arising from the nonlinearity of the viscous flux by an additional projection. We prove the entropy stability of the corresponding primal form for different treatments of the viscous flux; thus unifying the existing results in the literature as well as establishing the entropy stability for less-analyzed methods. Our analysis is also valid for the case of degenerate diffusion. Considering quasilinear elliptic problems in scalar settings, we prove that the proposed approach for viscous discretization is asymptotically consistent and adjoint consistent. For the special case of strongly monotone and globally Lipschitz problems, we prove the uniqueness and stability of the numerical solution. For this class of operators, we also provethe optimal convergence to the exact solution with respect to mesh size, in both energy and $L_2$ norms. Such optimal convergence rates for asymptotically (adjoint) consistent schemes have been observed before in numerical experiments.
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http://lambda-the-ultimate.org/node/2099
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## Non-Applicative Functional Languages
I am considering writing a paper about non-applicative functional language with the following abstract:
Non-applicative Functional Languages
Most of today's functional languages are examples of applicative languages. In other words
the operation of function application is generally implied between two consecutive terms.
This paper explores what it means for a language to be non-applicative, and what the implications
are in terms of basic operations such as the Y combinator.
Is this a topic that has already been explored? I only found one reference to "non-applicative languages" on Google scholar. Is anyone else interested in this topic? Any suggestions on how to make the abstract more appealing?
## Comment viewing options
### John Cowan
Well, concatenative languages (Forth, Joy, Factor, Cat, and others) are definitely non-applicative.
### Concatenative == Non-Applicative
My work on Cat is what is inspiring me to consider writing such an article. I haven't found any papers in the scholarly literature that formally discuss the differences between applicative and non-applicative languages. Do you think there would be some benefit of a formal comparison between the two classes of languages?
### Isn't this mostly syntax?
Writing "foo bar baz" in ML-like languages assumes left-to-right application, but you could simply put in parens "foo (bar baz)" for the effect of composition. In APL "foo bar baz ..." would be read as composition. Scheme requires the parens in either case, but it's equally easy to write (foo (bar (baz ...))) or (((foo bar) baz) ...).
... and have a look at the hooks, forks, and combinators of J.
Josh
### Definitions
I can't tell whether the syntactic issue is what cdiggins is after, but the definition of "applicative language" given in the topic is misleading. The more usual definition is something like this:
A programming language in which functions are repeatedly applied to the results of other functions and, in its pure form, there are no statements, only expressions without side effects.
(from here.) Of course, that looks a lot like a definition of FP, and Foldoc concurs.
### Thanks!
Thanks! I have some more studying to do!
### My reading of that article is that...
Functional programming = Applicative programming
Function-level programming = Point-free programming
I always understood applicative programming as a synonym for functional programming so I was very confused by the original question.
### Roughly, yes.
The "algebra" of programs is also a very strong aspect of Backus' view of FP. Concatenative languages tend to be extremely easy to formally manipulate. Part of the allure/reason for point-free style.
### The "algebra" of programs is
The "algebra" of programs is also a very strong aspect of Backus' view of FP. Concatenative languages tend to be extremely easy to formally manipulate.
Interesting! My problem with point-free style is that its comprehensibility doesn't seem to scale. That is, saying "avg = sum / count" is fine, but once you're doing anything complicated, I find it appallingly confusing. For example, the APL family impresses me greatly in terms of that "easy to manipulate" quality, but it looks like line noise to me. I am not referring to the character set issue; the same thing comes up in J and K.
I find that names have a strong documentary value. I wonder, can it be possible to achieve the same ease of manipulation, at a cost of some conciseness, by retaining names?
### line noise
There is that. Consider this line from the J entry to the 1999 ICFP contest:
dedge=: >: @: (+/~) @: (i. <. i.@-)
and their explanation, "The definition of dedge may be read as increment (>:) the addition table (+/~) of the minimum (<.) of the lists of increasing (i.) and decreasing (i.@-) non-negative integers."
WeightsTable = 1+ (table +) min(ints, rev ints)
(changing the implicit operation to composition and naming a few of the other symbols)? I think that it wouldn't take all that much to make it as readable as the equivalent code in any other language.
Josh
### The algebra of programming
Regarding the point-free style, you should look at Richard Bird and Oege de Moor's book The Algebra of Programming. That's based around relations rather than functions, and the inherent non-determinism discourages the use of variable names. Oege and I wrote a paper Pointwise Relational Programming (for AMAST in 2000) about trying to reintroduce the names, which are valuable both for documentation and for plumbing. It's tricky, though, because you lose beta-equivalence: (let x = 1 [] 2 in x+x) is not the same as ((1 [] 2) + (1 [] 2)), where "[]" denotes choice. Pointless programming is less of a problem functionally; see for example A Pointless Derivation of Radixsort, in which dispensing with variables simplifies the calculations considerably.
End of self-plug.
### re the radix sort paper: see
re the radix sort paper: see here (and the linked to discussion).
### Interesting! My problem with
Interesting! My problem with point-free style is that its comprehensibility doesn't seem to scale.
I agree. I believe point-free languages are most useful as intermediate languages.
The idea of Cat (a point-free stack-based non-applicative compositional language) was to be a back-end for imperative or functional languages, which could be easily extended and understood by human programmers.
What sets Cat apart from other intermediate languages (apart from a readable syntax) is that the fundamental operations are first class values. They can be quoted and passed to each other, making it a full-fledged functional language (according to some definitions).
I find that names have a strong documentary value. I wonder, can it be possible to achieve the same ease of manipulation, at a cost of some conciseness, by retaining names?
Yes, but at one point you will probably want to discard names if you want to express some kind of rewriting grammar (e.g. for optimization). The problem with retaining names all the way down to the lowest representation is that any optimization has to be expressed in terms of an abstract tree manipulation. This can be done, but it is hard to express, and becomes very coupled with the abstract representation of the language. In other words, it is bound to a specific implementation of a specific langauge. Going to a point-free form before optimization or transformation means that rewriting rules can be performed on the concrete syntax of the point-free language.
Someone please jump in if I am making too many unsubstantiated claims, or they feel I am mistaken.
### jumping in (not pushing or popping)
What sets Cat apart from other intermediate languages (apart from a readable syntax) is that the fundamental operations are first class values. They can be quoted and passed to each other, making it a full-fledged functional language (according to some definitions).
Both CPS and ANF intermediate forms are full-fledged functional languages [edit: link], with readable syntax (CPS is readable with practice and/or some syntactic sugar). At a slightly lower level, bytecode-based intermediate formats usually have readable assembler-like syntaxes, and such formats for functional languages are almost always higher-order (see e.g. the MacScheme machine). It would help to have some more specific examples of what you're comparing Cat to.
Yes, but at one point you will probably want to discard names if you want to express some kind of rewriting grammar (e.g. for optimization).
Why? See our previous discussion.
The problem with retaining names all the way down to the lowest representation is that any optimization has to be expressed in terms of an abstract tree manipulation. This can be done, but it is hard to express,
More initial implementation effort is involved in performing transformations on trees. So the question is really whether that extra effort, which has to be invested by the language implementor, is worth it. I think there's quite a bit of evidence indicating that it is.
and becomes very coupled with the abstract representation of the language. In other words, it is bound to a specific implementation of a specific langauge.
This doesn't make sense to me. The transformations you're describing are as bound to the point-free language as any transformations are on any language.
Going to a point-free form before optimization or transformation means that rewriting rules can be performed on the concrete syntax of the point-free language.
I don't think that's the issue. "Concrete syntax" would include characters like "[" and "]" (in Joy/Cat), which delimit what become quotations in the abstract syntax. I doubt there's any benefit to having transformations operate at that level -- they can just as well be performed on abstract syntax. It's just that the abstract syntax of stack languages has a simpler, more linear structure.
Someone please jump in if I am making too many unsubstantiated claims, or they feel I am mistaken.
See above. :) I think Qrczak's comment from the earlier discussion also needs to be addressed: stack-based languages don't seem to be a very good semantic match for imperative or functional source languages, or for real target machines, or for traditional VMs, so any benefit in ease of performing transformations in a stack-based language seems likely to be moot.
If you're saying that Cat would make a good VM for imperative or functional languages, the best way to demonstrate that would be to implement a simple language on top of Cat. Then the issue would become how the VM compares against VMs that have been designed around other criteria, which usually include efficient execution of the source language.
BTW, if I seem negative about this, I should mention that I do find the relationship between the lambda-based models and linear models interesting. However, my interest is more at the theoretical level in this case, because I'm not seeing the specific practical advantages you're claiming.
### Both CPS and ANF
Both CPS and ANF intermediate forms are full-fledged functional languages [edit: link], with readable syntax (CPS is readable with practice and/or some syntactic sugar). At a slightly lower level, bytecode-based intermediate formats usually have readable assembler-like syntaxes, and such formats for functional languages are almost always higher-order (see e.g. the MacScheme machine). It would help to have some more specific examples of what you're comparing Cat to.
Many of the most popular intermediate languages in use today e.g. JVML, MSIL, x86 assembly, and C aren't higher-order. I'll take back what I said about readable syntax though, since readability is such a subjective idea.
More initial implementation effort is involved in performing transformations on trees. So the question is really whether that extra effort, which has to be invested by the language implementor, is worth it. I think there's quite a bit of evidence indicating that it is.
You are saying that there is quite a bit of evidence to suggest that transformations on abstract trees is somehow better than transforming a flat format? I am unfamiliar with such evidence.
This doesn't make sense to me. The transformations you're describing are as bound to the point-free language as any transformations are on any language.
Sure, but my goal (which I am still a ways from achieving) is to find a common low-level language (e.g. Cat) to which other languages can be easily converted to. I don't see why manipulating a tree with names, could be advantageous to manipulating a point-free format. The rewriting algebra for compositional languages for Joy and Cat is trivial ( http://www.latrobe.edu.au/philosophy/phimvt/joy/j04alg.html ) and very general.
My thinking is that one could express a generic term rewriting optimization system using a similar grammar, and then apply it to languages X, Y, and Z. The requirement being that those languages have to first be converted to a compositional point-free form first. This alone seems to be fairly strong argument as for the usefulness of the compositional point-free form itself.
... stack-based languages don't seem to be a very good semantic match for imperative or functional source languages, or for real target machines, or for traditional VMs, ...
I don't understand. MSIL, JVML, x86 assembly, C, etc. are all examples of stack-based languages. What do you mean that they aren't good semantic matches for those various sources?
I should mention that I do find the relationship between the lambda-based models and linear models interesting
Have you had a chance to look at my most recent version of the Cat paper? I revised it again yesterday, and it is nearly submission-ready (I'm planning on submitting to ICFP). I'd be very interested in your comments.
### You are saying that there
You are saying that there is quite a bit of evidence to suggest that transformations on abstract trees is somehow better than transforming a flat format? I am unfamiliar with such evidence.
I'm saying that there's a great deal of evidence of the power of using lambda-based intermediate languages, particularly because of the transformations that they support. The SSA intermediate form used in compiling imperative languages also relies on the same properties.
The people who did this work were certainly aware of stack-based alternatives. It's not uncommon for virtual machines to be derived from such intermediate languages, and such machines are often at least partly stack-based. High-level transformations in such cases are done at the level of the lambda language, not at the VM level. The reason for that is that the intermediate language is designed primarily to support transformation and analysis, without irrelevant semantic artifacts, and the VM is designed to support important runtime properties, including efficient execution.
A language like Cat combines some properties of a good high-level intermediate language (supporting high-level transformations), as well as some properties of a VM. This could potentially be a good engineering compromise, but one of my concerns about it is that high-level ILs and VMs have competing constraints. Using the same language for both purposes will force you to make more compromises than if you separated the two.
If you do separate them, then you're free to design an ideal IL and an ideal VM for your purposes. I definitely don't see a Cat-like language as being an ideal IL for traditional functional language, and it probably isn't ideal for imperative languages either (more on this below). I'm sure it can be made into a good VM, although I suspect that you'll want to add optimizations to support source language characteristics, similar to those found in the JVM or MSIL, moving away from the pure stack model and towards more traditional VMs.
Sure, but my goal (which I am still a ways from achieving) is to find a common low-level language (e.g. Cat) to which other languages can be easily converted to.
[...]
My thinking is that one could express a generic term rewriting optimization system using a similar grammar, and then apply it to languages X, Y, and Z. The requirement being that those languages have to first be converted to a compositional point-free form first. This alone seems to be fairly strong argument as for the usefulness of the compositional point-free form itself.
It's at least an equally strong argument for CPS or ANF-based intermediate languages, which make excellent candidates for this purpose. See e.g. Realistic Compilation by Program Transformation, which describes a system that compiles BASIC, Pascal, and Scheme, through an intermediate CPS languages, to native code. VMs are easily derived from such ILs.
PLT Scheme has implementations of Java and Python which compile to either Scheme or their core lambda language (not sure which), and their IDE takes advantage of the common intermediate representation for visualizing program structure during development and debugging. In that case, the presence of local names in the IL is critical.
But the problem with a common low-level language is not so much finding a common representation for the basic computational features of multiple languages -- I'd say that's pretty much a solved problem, with various credible solutions. The real problem is dealing with differences in things like data types, object systems, etc. That's one of the biggest reasons that the JVM and CLR don't make such great general-purpose language targets, even though the CLR was specifically designed for that purpose. The papers on C-- cover some similar issues.
I don't see why manipulating a tree with names, could be advantageous to manipulating a point-free format. The rewriting algebra for compositional languages for Joy and Cat is trivial ( http://www.latrobe.edu.au/philosophy/phimvt/joy/j04alg.html ) and very general.
The comment of Qrczak's which I linked to earlier gets into this. Any stack-related artifacts in the IL will be detrimental to suitability as a language for analysis and transformation.
I don't understand. MSIL, JVML, x86 assembly, C, etc. are all examples of stack-based languages. What do you mean that they aren't good semantic matches for those various sources?
I should have written "concatenative" (substitute equivalent term to taste), not stack-based. MSIL and JVML both have all sorts of optimizations for the source languages they're designed to support, e.g. to do with local variable stack frames, and as you know are certainly not concatenative. x86 assembly isn't a good semantic match for anything. :) More seriously, x86 isn't relevant, because no-one uses it by choice as an intermediate format, and besides it's also heavily register-based. C is about as stack-based as the lambda calculus, so clearly I should have been more specific.
Have you had a chance to look at my most recent version of the Cat paper? I revised it again yesterday, and it is nearly submission-ready (I'm planning on submitting to ICFP). I'd be very interested in your comments.
I looked at the first draft which you posted about here. That seemed mostly focused on the type system, which doesn't interest me as much. If that's changed, I'll take another look.
### Food for thought
Thanks for sharing your ideas and knowledge Anton.
I looked at the first draft which you posted about here. That seemed mostly focused on the type system, which doesn't interest me as much. If that's changed, I'll take another look.
I now describe the operational semantics in the paper, I no longer talk about the S-K caclulucs, and discuss other aspects of the language.
### Interpreting the question
Re the original question, I think it intended to refer to the issues mentioned in the Joy FAQ, of applicative vs. "compositional" languages. Here's a relevant sentence:
Any functional language which completely replaces application, by explicit or implicit "@", by composition, with explicit or implicit "." or ";", might be called a compositional functional language.
"Composition" here refers to the idea that all program terms in Joy denote functions from stacks to stacks, and a program is simply a composition of such functions.
So the comparison is between traditional applicative languages in which programs consist of "functions repeatedly applied to the results of other functions" and compositional languages in which programs consist entirely of functions composed with other functions.
### Can Programming Be Liberated from the von Neumann Style?
Not listed on that Wikipedia page, but very on-topic: Can Programming Be Liberated from the von Neumann Style?
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http://physics.stackexchange.com/questions/28300/reference-needed-for-iron-based-superconductors?answertab=votes
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# Reference needed for Iron-based superconductors
Iron-based superconductor is a class of high-$T_c$ superconductors discovered in 2008.
Are there any review papers about these superconductors yet? If not, which are the key papers in the field?
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## 2 Answers
For specific recommendations, the review in Nature by Paglione and Greene is very highly cited and accessible. There is a review of the magnetic properties by Lumsden and Christianson and a somewhat older article is available from Hosono and collaborators. A Nature review on the debate over the pairing mechanism is available from Mazin
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+1 for LMGTFY.$\,$ – Warrick May 15 '12 at 14:36
10.1103/RevModPhys.83.1589: A comprehensive review in Dec 2011 by G. R. Stewart containing a myriad of key experimental and theoretical results.
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http://mathematica.stackexchange.com/users/2241/minthao-2011?tab=activity&sort=all&page=2
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minthao_2011
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Jan24 revised How can I get all solutions of a system of equations with Reduce? added 11 characters in body Jan24 asked How can I get all solutions of a system of equations with Reduce? Jan7 awarded Popular Question Dec23 comment How to select a list from a list? I am sorry. I did. Dec23 comment How to select a list from a list? If each element contains four points, for example, {{-5, -1, -1}, {-5, -1, 3}, {-5, 4, -2}, {3, -1, -5}}. I tried Select[nonright, (12 == Length[Union @@@ #] &)] it does not correct. Please help me. Dec22 comment How to select a list from a list? Thank you very much. Dec22 comment How to select a list from a list? @ belisarius In line Select[lst, ( 9 == Length[Union @@ #] &)] If I want 9 numbers different from 0. How can I select? Dec21 revised How to select a list from a list? deleted 2 characters in body Dec21 comment How to select a list from a list? Yes. I will edit my question. Dec21 comment How to select a list from a list? You understand me. Thank you very much. Dec21 accepted How to select a list from a list? Dec21 revised How to select a list from a list? added 35 characters in body Dec21 revised How to select a list from a list? added 46 characters in body Dec21 asked How to select a list from a list? Dec18 accepted How can I use the command Minimize of this trigonometric function? Dec17 asked How can I use the command Minimize of this trigonometric function? Oct21 awarded Nice Question Oct6 accepted How can I find the greatest of this expression? Oct5 asked How can I find the greatest of this expression? Sep9 awarded Yearling
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https://www.statistics-lab.com/category/%E4%BA%91%E8%AE%A1%E7%AE%97%E4%BB%A3%E5%86%99/
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## 计算机代写|云计算代写cloud computing代考|CS4740
statistics-lab™ 为您的留学生涯保驾护航 在代写云计算cloud computing方面已经树立了自己的口碑, 保证靠谱, 高质且原创的统计Statistics代写服务。我们的专家在代写云计算cloud computing代写方面经验极为丰富，各种代写云计算cloud computing相关的作业也就用不着说。
• Statistical Inference 统计推断
• Statistical Computing 统计计算
• Advanced Probability Theory 高等概率论
• Advanced Mathematical Statistics 高等数理统计学
• (Generalized) Linear Models 广义线性模型
• Statistical Machine Learning 统计机器学习
• Longitudinal Data Analysis 纵向数据分析
• Foundations of Data Science 数据科学基础
## 计算机代写|云计算代写cloud computing代考|Static Power Management
The static power management can be executed on both hardware and software levels. Leakage currents in any active circuits cause static power consumption at the hardware level [7]. SPM uses hardware components such as CPU, memory, disk storage, network devices, and power supply unit efficiently. It consists of all applied optimization methods during design time at logic, circuit, and architectural levels that will he explained in the following section.
• Logic level optimization: At this level, optimization methods attempt to optimize the power of switching activity in both sequential and combinational circuits. Minimizing the switching capacitance improves the dynamic power consumption straightly by reducing the energy per transition on each logic device $[7,41]$.
• Circuit level optimization: Significant challenges at this optimization level are based on efficient pipelining and interconnections between stages and components. Pipelining technique is regularly used to boost throughput in highperformance designs at the expense of reducing energy efficiency, contributing to increasing area and execution time [41].
• Architectural level optimization: Methods include the system’s design considering power optimization technique at an architectural level [7]. Power savings are typically accomplished at the architectural level by optimizing the system components’ balance to prevent wasting power.[41].
Besides the optimization at the hardware level, considering the SPM at the software level is also essential. Even with robust hardware design, it is crucial to be careful about software design inasmuch as weak design conduces to loss of power and performance, even with perfectly designed hardware. Thus, the code generation, the instructions used in the code, and the order of these instructions must be carefully selected, as they affect performance as well as power consumption.
## 计算机代写|云计算代写cloud computing代考|Dynamic Power Management
This section describes our taxonomy at the dynamic power management level, as shown in Fig. 2.3. DPM is categorized into three levels, including hardware, software, and hybrid. There are various kinds of optimization methods at both the hardware and software levels $[7,42]$. At the hardware level, we can imply techniques such as DVFS, DCD, and sleep states. In addition, the techniques at the software level aree classified into virtualization, migration, consolidation, plus containerization. The dynamic power consumption is induced by the high usage of hardware components (such as CPU, storage, and network devices) and the circuits’ activity. The main reason enabling dynamic power consumption pertain to both system’s components deactivation and tuning the circuit activity. Dynamic power consumption can be reached through different techniques including: (1) diminishing the switching activity, (2) decreasing the physical capacitance that relies on low-level design parameters such as transistors’ sizes, (3) ebbing the supply voltage, and (4) lessening the clock frequency [7].
DPM improves energy consumption by using knowledge gathered from current resources in the system and the workload of applications running in the system [7, 43]. DPM techniques allow dynamic adjustment of power states to occur based on current system loads. It predicts the best action in the future using the data obtained from the system and according to the system’s requirements. DPM techniques are categorized into hardware and software levels. There is another level in our taxonomy, namely hybrid, in which both hardware and software techniques are simultaneously utilized.
1. Hardware-level approaches
DPM techniques applied at the hardware level reconfigure the system dynamically by adopting methodologies to fulfill the requested services with the minimum number of active components or the minimum load on such components [43]. The DPM techniques at a hardware level can optionally turn off the idle system components or reduce the useless ones’ performance. It is also possible to exchange some components, containing CPU, between either active or idle modes to save energy. The hardware DPM techniques vary for different hardware components, yet usually, they are splitted into dynamic component deactivation (DCD) and dynamic performance scaling (DPS) [44].
## 计算机代写|云计算代写cloud computing代考|.静态电源管理
• 逻辑级优化:在这个级别上，优化方法试图优化顺序电路和组合电路中开关活动的功率。最小化开关电容通过减少每个逻辑器件上的每次跃迁能量直接提高了动态功耗$[7,41]$。
• 电路级优化:在这一优化级别上的重大挑战是基于级和组件之间的高效流水线和互连。流水线技术经常被用于提高高性能设计的吞吐量，以降低能源效率为代价，有助于增加面积和执行时间[41]。
• 体系结构级优化:方法包括体系结构级考虑功率优化技术的系统设计[7]。节能通常是通过优化系统组件的平衡在架构级实现的，以防止浪费电力除了硬件层面的优化，考虑软件层面的SPM也是必不可少的。即使有健壮的硬件设计，对软件设计也要小心谨慎，因为即使有完美设计的硬件，薄弱的设计也会导致功率和性能的损失。因此，必须仔细选择代码生成、代码中使用的指令以及这些指令的顺序，因为它们影响性能和功耗
计算机代写|云计算代写cloud computing代考|Dynamic Power Management .本节描述了我们在动态电源管理级别的分类，如图2.3所示。DPM分为三个级别，包括硬件、软件和混合。在硬件和软件层面都有各种各样的优化方法$[7,42]$。在硬件级别，我们可以使用DVFS、DCD和睡眠状态等技术。此外，软件级别的技术可以分为虚拟化、迁移、整合和容器化。动态功率消耗是由硬件组件(如CPU、存储和网络设备)和电路活动的高使用率引起的。实现动态功耗的主要原因与两个系统组件的失活和调优电路活动有关。动态功耗可以通过不同的技术实现，包括:(1)降低开关活性，(2)降低物理电容(依赖于低水平的设计参数，如晶体管的尺寸)，(3)降低电源电压，(4)降低时钟频率[7]DPM通过使用从系统中当前资源收集的知识和系统中运行的应用程序的工作负载来提高能耗[7,43]。DPM技术允许根据当前系统负载动态调整电源状态。它利用从系统中获得的数据，根据系统的需求，预测未来的最佳行动。DPM技术分为硬件级和软件级。在我们的分类法中还有另一个层次，即混合分类法，即同时使用硬件和软件技术硬件级方法应用于硬件级的DPM技术通过采用各种方法动态地重新配置系统，以实现所请求的服务，使用最少的活动组件数量或这些组件上的最小负载[43]。硬件级别的DPM技术可以选择关闭空闲的系统组件或降低无用的系统组件的性能。也可以在活动或空闲模式之间交换一些组件，包括CPU，以节省能源。硬件DPM技术因硬件组件的不同而不同，但通常分为动态组件去激活(DCD)和动态性能缩放(DPS) [44].
## 有限元方法代写
tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。
## MATLAB代写
MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。
## 计算机代写|云计算代写cloud computing代考|CS5412
statistics-lab™ 为您的留学生涯保驾护航 在代写云计算cloud computing方面已经树立了自己的口碑, 保证靠谱, 高质且原创的统计Statistics代写服务。我们的专家在代写云计算cloud computing代写方面经验极为丰富，各种代写云计算cloud computing相关的作业也就用不着说。
• Statistical Inference 统计推断
• Statistical Computing 统计计算
• Advanced Probability Theory 高等概率论
• Advanced Mathematical Statistics 高等数理统计学
• (Generalized) Linear Models 广义线性模型
• Statistical Machine Learning 统计机器学习
• Longitudinal Data Analysis 纵向数据分析
• Foundations of Data Science 数据科学基础
## 计算机代写|云计算代写cloud computing代考|Proposed Taxonomy for Energy-Aware Resource
In this section, we present our proposed taxonomy for energy-aware resource management solutions in cloud environments, as shown in Fig. 2.2. In our proposed taxonomy, we consider four items at the highest level. The first level pertains to the goals of energy-efficient resource management in cloud environments. As can be seen, the second level goes back to the dynamism of resource management technique. The third level is the considered type of workload, including arbitrary, High-Performance Computing (HPC), batch, and real-time applications. Finally, the fourth level is the type of resources that are classified into active and passive. The details of this taxonomy are described in the following subsection.
As energy-efficient resource management approaches play a crucial role in cloud data centers these days, there are various kinds of goals in this way. To clarify, Fig. $2.2$ summarizes the components of goals. Indeed, we have considered five targets for this component, such as minimizing power consumption, maximizing performance, load balancing, meeting power budget, plus maximizing business profit. We have also regarded four performance metrics, including response time, SLA violation, throughput, and delay. First and foremost, data centers have significant power cost; thereby, it is an essential requirement for data centers’ operation to meet the power budget coming from the limitation for power usage and observing this limitation [25].
Due to load imbalance, some of the data center resources may become overloaded or underloaded, which leads to performance degradation and resource wastage. Load balancing conduces to maximize resource utilization and achieve the desired QoS in the cloud by employing optimal resource allocation and workload distribution approaches at both schedule and runtime.
• Batch processing: Theoretically, batch processing is a processing mode when a sequence of jobs are executed on a batch of inputs [27]. Analyzing data on a large scale and batch processing occurs by utilizing data centers and some distributed and computing frameworks such as Map-Reduce and Hadoop [4]. Map-Reduce programming paradigm is the most practical and efficient solution for batch processing of big data [28].
• HPC: In the early 1990s, clusters of computers became famous in HPC environments owing to their low cost compared to custom supercomputers and mainframes [29]. Also, HPC computers generally take advantage of open source operating systems such as Linux. In the early 2000s, grid computing was linked to the HPC community as a consequence of need to run parallel programs even larger than that was normal in grid environments. Grids provide powerful resources operated by independent administrative domains to users [30]. In the late 2000 s, cloud computing was quickly growing its adolescent level and reputation, and studies started to appear on the viability of executing HPC applications on remote cloud resources [31, 32]. HPC applications are resource-intensive scientific workflows (in terms of data, computation, and communication) that have usually aimed at Grids and customary HPC platforms like super-computing clusters [33]. Both the size and number of HPC data centers have overgrown in recent years, which conduces to an exponential increase in power drastically [34].
• Real-time application: With improved cloud computing infrastructure, realtime computing can be accomplished on cloud infrastructure [35]. In most of the real-time cloud applications, the processing is executed on remote cloud computing nodes. As we meet many real-time systems around us, Cloud’s support plays a crucial role in the real-time system [36]. Their application ranges from small mobile phones to huge industrial controls and from a mini pacemaker to larger nuclear plants. A usual real-time, such as financial analysis, distributed databases, or image processing, includes multiple real-time applications or subtasks service [37]. Real-time systems are implemented by several simultaneous tasks requesting to access hardware resources [24].
## 计算机代写|云计算代写cloud computing代考|能源感知资源的建议分类法
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• HPC:在20世纪90年代早期，集群计算机因其与定制超级计算机和大型机[29]相比的低成本而在HPC环境中出名。此外，高性能计算计算机通常利用开源操作系统，如Linux。在21世纪初，网格计算与HPC社区联系在一起，因为需要运行比网格环境中正常情况下更大的并行程序。网格为用户[30]提供了由独立管理域操作的强大资源。在2000年代后期，云计算的水平和声誉迅速提高，在远程云资源上执行高性能计算应用的可行性研究开始出现[31,32]。HPC应用程序是资源密集型的科学工作流(就数据、计算和通信而言)，通常针对网格和传统的HPC平台，如超级计算集群[33]。近年来，HPC数据中心的规模和数量都急剧增长，这导致了功率的指数级急剧增长
## 有限元方法代写
tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。
## MATLAB代写
MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。
## 计算机代写|云计算代写cloud computing代考|ECE4150
statistics-lab™ 为您的留学生涯保驾护航 在代写云计算cloud computing方面已经树立了自己的口碑, 保证靠谱, 高质且原创的统计Statistics代写服务。我们的专家在代写云计算cloud computing代写方面经验极为丰富，各种代写云计算cloud computing相关的作业也就用不着说。
• Statistical Inference 统计推断
• Statistical Computing 统计计算
• Advanced Probability Theory 高等概率论
• Advanced Mathematical Statistics 高等数理统计学
• (Generalized) Linear Models 广义线性模型
• Statistical Machine Learning 统计机器学习
• Longitudinal Data Analysis 纵向数据分析
• Foundations of Data Science 数据科学基础
## 计算机代写|云计算代写cloud computing代考|Motivation and Contribution
With the rapid ever-increasing demand to access diverse information and communication technology services based on the cloud service delivery model, the number of huge energy-hungry cloud data centers is increasing rapidly. Thus, these days energy consumption in cloud environments is a crucial issue. A data center will consume the energy of about 1000TWH in next ten years (2013-2025) [6]. The percentage of energy consumption by the data centers and cooling systems will reach $5 \%$ of the total energy consumption in the world. Energy consumption leads to operational cost and environmental implications such as global warming [7].
This key challenge leads to a rethink about the techniques and research strategies to lessen energy consumption as a crucial matter in the cloud environment. To overwhelm this challenge, there are various solutions that researchers have introduced; among them, resource management techniques play a significant role. Nonetheless, energy efficiency is still a challenge for future researchers [8]. Virtualization technique enables cloud providers to create multiple Virtual Machine(VM) instances on a single physical server, or multiple containers on a VM or a physical server which makes it possible to have servers with higher utilization. The dynamic consolidation of both VMs and containers through live migration is an efficient approaches for saving energy in cloud data centers [9]. Although the recent technological developments and paradigms including High-Performance Computing (HPC), containerization, exascale computing, and processing at network edge appear to yield new opportunities for cloud computing, they are also creating new challenges and demands for new approaches and research strategies.
Container technology has emerged thanks to Docker [10] which has boosted in both academia and industry. It provides a way to package an application that can be run with its dependencies and libraries isolated from other applications. Containers arose as a lightweight alternative of VMs that present better microservice architecture supports. The technology of container is strongly supported by PaaS, IaaS, and Internet Service Providers. Traditional hypervisor-based solutions are virtualized at the hardware level, while containerization provides virtualization at the operating system level. The containers interact with each other via system standard calls and they do not have any information about themselves [11]. Although VM technology needs to have an individual operating system for each VM, only one operating system can serve all containers in container technology. So, container technology provides more lightweight virtual systems which makes it possible to utilize system resources such as CPU, RAM, and network bandwidth more efficiently [10]. This happens owing to Linux kernel’s cgroups and namespaces which are used by docker. Besides, utilizing container technology considerably decreases startup time and the expected resources for each image in comparison with VM technology. To exemplify, a container requires 50 milliseconds to start, while a VM is activated in $30-40$ seconds [12].
Many Internet companies have embraced this technology and containers have become the de-facto standard for creating, publishing, and running applications. On the other side, there are still impediments and challenges in container-based virtualization demanding to be addressed, including security issues, in particular, during migration, dynamic resource allocation, and energy consumption [13].
## 计算机代写|云计算代写cloud computing代考|Related Work
Energy-efficient resource management approaches in cloud environments are a hot topic which vastly addressed by researchers. Since cloud computing’s research has advanced continuously, there is a need for a systematic review to evaluate, update, and join the existing literature. This section summarizes some of the previous works in the literature similar to our work, the result of which is shown in Table 2.1.
The authors in [15] have conducted a survey on energy-aware resource allocation in cloud data centers. They have reviewed some keywords such as virtualization, allocation of VM, energy efficiency, power consumption, as well as cloud computing. They have discussed various kinds of energy-aware system architectures for the cloud and compared energy efficiency in both traditional and virtual data centers. This chapter has further proposed a taxonomy for energy-saving methods in cloud data centers, which were studied in three levels, such as power management, resource management, and thermal management. The researchers have reviewed previous works based on VM allocation algorithms, VM selection algorithms, and Dynamic Voltage Frequency Scaling(DVFS), which conduced to energy saving. Plus, they have shown that the energy-saving approach became possible using renewable energy that plenty of recent research introduced this strategy.
In [16] the authors have presented a brief survey describing primary energyconserving techniques in the cloud environment. To add, they have classified energy consumption approaches into five categories, including energy-efficient hardware, energy-aware scheduling, consolidation, energy conservation in a cluster of servers, as well as power-efficient networks. Finally, they have evaluated a few papers based on this classification. The researchers further have focused on consolidation techniques in three levels, containing task consolidation, server consolidation, and energy-aware task consolidation.
Researchers in [24] have performed a comprehensive survey on energy-efficient computing, clusters, grids, and clouds. They have reported a number of approaches in the literature which contributed to improve energy efficiency. This chapter has proposed three taxonomies, covering such levels as scheduling, energy-efficient computing, as well as energy-efficient technique at different levels to make data center greener. Plus, [24] studied the energy efficiency of a single system and largescale cloud data centers, storage systems, and networking.
## 计算机代写|云计算代写cloud computing代考|动机和贡献
. cloud computing
## 计算机代写|云计算代写cloud computing代考|相关工作
. bat
[24]的研究人员对节能计算、集群、网格和云进行了全面的调查。他们在文献中报告了一些有助于提高能源效率的方法。本章提出了三个分类，包括调度、节能计算和不同级别的节能技术，使数据中心更绿色。此外，[24]研究了单个系统和大型云数据中心、存储系统和网络的能源效率
## 有限元方法代写
tatistics-lab作为专业的留学生服务机构，多年来已为美国、英国、加拿大、澳洲等留学热门地的学生提供专业的学术服务，包括但不限于Essay代写，Assignment代写，Dissertation代写，Report代写，小组作业代写，Proposal代写，Paper代写，Presentation代写，计算机作业代写，论文修改和润色，网课代做，exam代考等等。写作范围涵盖高中，本科，研究生等海外留学全阶段，辐射金融，经济学，会计学，审计学，管理学等全球99%专业科目。写作团队既有专业英语母语作者，也有海外名校硕博留学生，每位写作老师都拥有过硬的语言能力，专业的学科背景和学术写作经验。我们承诺100%原创，100%专业，100%准时，100%满意。
## MATLAB代写
MATLAB 是一种用于技术计算的高性能语言。它将计算、可视化和编程集成在一个易于使用的环境中，其中问题和解决方案以熟悉的数学符号表示。典型用途包括：数学和计算算法开发建模、仿真和原型制作数据分析、探索和可视化科学和工程图形应用程序开发，包括图形用户界面构建MATLAB 是一个交互式系统，其基本数据元素是一个不需要维度的数组。这使您可以解决许多技术计算问题，尤其是那些具有矩阵和向量公式的问题，而只需用 C 或 Fortran 等标量非交互式语言编写程序所需的时间的一小部分。MATLAB 名称代表矩阵实验室。MATLAB 最初的编写目的是提供对由 LINPACK 和 EISPACK 项目开发的矩阵软件的轻松访问，这两个项目共同代表了矩阵计算软件的最新技术。MATLAB 经过多年的发展，得到了许多用户的投入。在大学环境中，它是数学、工程和科学入门和高级课程的标准教学工具。在工业领域，MATLAB 是高效研究、开发和分析的首选工具。MATLAB 具有一系列称为工具箱的特定于应用程序的解决方案。对于大多数 MATLAB 用户来说非常重要，工具箱允许您学习应用专业技术。工具箱是 MATLAB 函数（M 文件）的综合集合，可扩展 MATLAB 环境以解决特定类别的问题。可用工具箱的领域包括信号处理、控制系统、神经网络、模糊逻辑、小波、仿真等。
|
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https://docs.mosek.com/9.0/install/installation.html
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# 4 Installation¶
## 4.1 Only Python¶
If MOSEK is only used from Python, then to easily install the latest version together with all the binary dependencies we recommend:
• Users of the Anaconda Python distribution can install MOSEK as an Anaconda package, see https://anaconda.org/MOSEK/mosek. The quick way is
conda install -c mosek mosek
• Alternatively use the PIP installer with:
pip install -f https://download.mosek.com/stable/wheel/index.html Mosek --user
(skip --user for a system-wide installation).
## 4.2 General setup¶
### 4.2.1 Linux¶
<MSKHOME>/mosek/9.0/tools/platform/linux64x86/bin
to the OS variable PATH, where <MSKHOME> is the directory where MOSEK was installed.
### 4.2.2 Mac OS¶
2. Run the command
python <MSKHOME>/mosek/9.0/tools/platform/osx64x86/bin/install.py
where <MSKHOME> is the directory where MOSEK was installed. This will set up the appropriate shared objects required when using MOSEK.
<MSKHOME>/mosek/9.0/tools/platform/osx64x86/bin
to the OS variable PATH.
4. Troubleshooting: If running the install.py script produces errors such as:
xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun
...
CalledProcessError: Command '['otool', '-L', '/users/username/mosek/9.0/tools/platform/osx64x86/bin/MOSEKLM']' returned non-zero exit status 1
then you need to install the command line tools, in particular otool. This can be done with
xcode-select --switch /Library/Developer/CommandLineTools
### 4.2.3 Windows, MSI installer¶
1. Make the right choice between the 32bit and 64bit versions. For instance if you plan to use MOSEK with 32bit Python or MATLAB the 32bit version of MOSEK should be selected. In general it is recommend to use the 64bit version though.
3. Run the installer to complete the installation.
4. Check that the path
<MSKHOME>\mosek\9.0\tools\platform\<PLATFORM>\bin
was added to the OS variable PATH, where <MSKHOME> is the directory where MOSEK was installed and <PLATFORM> is win64x86 or win32x86 depending on the version of MOSEK installed. This is necessary for Windows to locate the MOSEK shared libraries.
### 4.2.4 Windows, Manual installation¶
1. Make the right choice between the 32bit and 64bit versions. For instance if you plan to use MOSEK with 32bit Python or MATLAB the 32bit version of MOSEK should be selected. In general it is recommend to use the 64bit version though.
2. Download the Windows 32bit x86 or Windows 64bit x86 MOSEK Optimization Suite distribution from https://mosek.com/downloads/ and unpack it into a chosen directory.
<MSKHOME>\mosek\9.0\tools\platform\<PLATFORM>\bin
to the OS variable PATH, where <MSKHOME> is the directory where MOSEK was installed and <PLATFORM> is win64x86 or win32x86 depending on the version of MOSEK installed. This is necessary for Windows to locate the MOSEK shared libraries, especially if MOSEK is to be used e.g. from MATLAB.
## 4.3 Setting up the License¶
Regardless of the method of installation, MOSEK requires a license file to run.
Token server setup
If you are using a floating license with a token server then follow the instructions in the Licensing Guide. This step is NOT required for trial and personal academic licenses in particular.
Client setup
In practice the license is contained in a file called
mosek.lic
which should typically be saved to a file called
%USERPROFILE%\mosek\mosek.lic (Windows)
\$HOME/mosek/mosek.lic (Linux, MacOS)
If the folder mosek in the home directory does not exists, then it should be created. The license can be tested with the program msktestlic. For further information about the license system, and other non-standard ways of setting up the license, please consult the License Guide.
## 4.4 Finishing up¶
Important
• See the Licensing Guide if you need more advanced help setting up the license.
• For most languages and interfaces some additional steps are required. Please follow the instructions in the relevant interface documentation available from https://mosek.com/documentation/.
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http://cp3-origins.dk/a/18416
|
The elastic $$I=1/2$$, $$s$$- and $$p$$-wave kaon-pion scattering amplitudes are calculated using a single ensemble of anisotropic lattice QCD gauge field configurations with $$N_{\mathrm{f}} = 2+1$$ flavors of dynamical Wilson-clover fermions at $$m_{\pi} = 230\mathrm{MeV}$$. A large spatial extent of $$L = 3.7\mathrm{fm}$$ enables a good energy resolution while partial wave mixing due to the reduced symmetries of the finite volume is treated explicitly.The $$p$$-wave amplitude is well described by a Breit-Wigner shape with parameters $$m_{K^{*}}/m_{\pi} = 3.808(18)$$ and $$g^{\mathrm{BW}}_{K^{*}K\pi} = 5.33(20)$$ which are insensitive to the inclusion of $$d$$-wave mixing and variation of the $$s$$-wave parametrization. An effective range description of the near-threshold $$s$$-wave amplitude yields $$m_{\pi}a_0 = -0.353(25)$$.
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https://www.physicsforums.com/threads/studying-for-exam-need-help.52708/
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# Studying for exam, need help
1. Nov 14, 2004
### johnnyICON
Studying for exam, need help!!
Hi can someone help me out. My girlfriend has an exam tomorrow and she got stuck on this question. Her professor decided not to give out any solutions she's not too sure if she is heading in the right direction. Any help would be great, thank you in advance.
Here is the question:
Prove by using the definition of the limit of a sequence that:
$$\lim_{n \to \infty} \frac{n + 1}{n^2} + 3 = 3$$
Last edited: Nov 14, 2004
2. Nov 14, 2004
### mattmns
split up the fraction
$$\frac{n}{n^2} + \frac{1}{n^2}$$
3. Nov 15, 2004
### johnnyICON
How do I get just one term of n?
4. Nov 15, 2004
### matt grime
You must show that given e>0 there is an N such that n>N implies
$$\frac{n+1}{n^2}<e$$
agreed?
Well,
$$\frac{n+1}{n^2}<\frac{n+1}{(n+1)^2} = \frac{1}{n+1}$$
so pick N such that N+1>1/e
5. Nov 15, 2004
### johnnyICON
Second question, if you could get back to me asap, we're at school cramming right now
Let$$a_n = \frac{n^2-1}{2n^2+3}$$ Prove by using the definition of the limit of a sequence that $$\lim_{n \to \infty}a_n = \frac{1}{2}$$
6. Nov 15, 2004
### matt grime
Well, have you simplified a_n -1/2?
every question like this reduces to showing something tends to zero. that thing tends to zero for obvious reasons just like the previous example
7. Nov 15, 2004
### johnnyICON
I just have $$|\frac{n^2-1}{2n^2+3} - \frac{1}{2}|$$ and I don't know how to get it to a single n term.
8. Nov 15, 2004
### johnnyICON
Thanks for your help anyway. We gotta go now.
Similar Discussions: Studying for exam, need help
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https://livingthing.danmackinlay.name/latex.html
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LaΤeΧ
...and ΤΕΧ, and ConTeXt and XeTeX and TeXleMeElmo
The least worst mathematical typesetting system. One of the better scoured of the filthy pipes in the academic plumbing. De facto standard for mathematicians, especially those who are not so impertinent as to insist in writing in non-English languages, or are not so shallow as deny the simple delight of the painstaking handicraft of manually setting line breaks, or have grad students who will deal with all that shit for free. That is, a tool that meets the needs of the Tenured Academic sufficiently, and that the rest of us survive.
Other alternatives include
1. using MS Word, and
2. stabbing your eyeballs with a pencil
… each of which I regard as similarly undesirable, and, to be clear, both marginally less desirable than LaTeX itself, despite my qualms.
Addendum: Yes, I am aware there are differences due to various different engines, formats, macro systems etc, giving us ConTeXT and LaTeX and TeX and pdftex and xetex and luatex, and that they are all refreshingly different in their choices of pain-points in formatting, interoperation, character set handling, compatibility, and community support. However, standards lock-in being what it is, I believe I can avoid arranging the deckchairs on this sinking boat by waiting for incremental improvements to make a difference. I will discretely wait over here, near the HTML lifeboats, for some amped-up scholarly version of Markdown to come save me and render the entire tiresome situation irrelevant..
History
Eddie Smith, From boiling lead and black art: An essay on the history of mathematical typography; the only thing on this page you might conceivably read for pleasure.
Robert Kosara has an excellent rant:
The tools of the trade for academics and others who write research papers are among the worst software has to offer. Whether it’s writing or citation management, there are countless issues and annoyances. How is it possible that this fairly straightforward category of software is so outdated and awful?
Grad students, Robert. Grad student labour. The same labour undervaluation that keeps slave economies from developing the steam engine.
Here is a more fannish, upbeat and pious take by Graham Douglas, Whats in a name: a guide to the many flavours of Tex.
Documentation I frequently need to find
Include LaTeX in python
Including arbitrary LaTeX in python scripts, jupyter notebooks, Pweave literate documents? Use an ingenious script calledusing latex_fragment. It was written by that paragon of coding cleanliness, by that tireless crusader for not-dicking-around, me.
from IPython.display import display_latex, display
import latex_fragment
l = latex_fragment.LatexFragment(r'$x=y$')
display(l)
Note also that pandoc markdown already includes LaTeX support.
Make TeX run like a normal unix program
As opposed to the default pointless-error-interaction-mode-that-briefly-thought-that-it-would-be-hip-in-the-80s.
pdflatex -interaction=nonstopmode -halt-on-error
Bloody-minded compile-my-document-at-all-costs-I-don’t-care-how-it-is-broken:
pdflatex -interaction=batchmode
Death-or-define macro
Death-or-define is how I think of the trick to force a macro definition redefinition even if there is no definition to be redefined — handy if you are rendering latex from some tricky source such as jupyter, or where you don’t have control over the overall document outside your section but don’t care about wreaking havoc on your collaborators; some other poor sap can deal with the macro mutation weirdness.
\providecommand{\foo}{}
\renewcommand{\foo}[1]{bar: #1}
Algorithms/pseudocode
Confusing profusion of options.
tl;dr: use
• a hip markup such as
• algorithmicx + algpseudocode (a nice default syntax that comes with algorithmicx), or
• program
• inside an algorithm float.
\usepackage{algorithmicx}
\usepackage{algpseudocode}
\usepackage{algorithms}
\begin{algorithm}
\caption{Euclid’s algorithm}
\label{euclid}
\begin{algorithmic}[1] % The argument is the first line number
\Procedure{Euclid}{$a,b$} \Comment{The g.c.d. of a and b}
\State $r\gets a \bmod b$
\While{$r\not=0$} \Comment{We have the answer if r is 0}
\State $a \gets b$
\State $b \gets r$
\State $r \gets a \bmod b$
\EndWhile\label{euclidendwhile}
\State \textbf{return} $b$\Comment{The gcd is b}
\EndProcedure
\end{algorithmic}
\end{algorithm}
Are you running minimalist TeX? You’ll need
tlmgr install algorithmicx algorithms
or you can do without algorithms if you do
\usepackage{float}
\newfloat{algorithm}{t}{lop}
Minimalist TeX
MacTeX wastes your hard disk space if you install the whole gigantic thing. 5Gb for a 1980s typesetting system is cheeky, especially from people who delight in claiming that Microsoft Word is over-engineered, and that they are keeping it serious with their svelte, elegant, professional alternative. But LaTex is not “serious typesetting”, except in the sense that driving a panzer to work is “serious commuting”. (In this metaphor, Microsoft Word is some kind of polka-dotted clown car, as far as mathematics is concerned.)
However! You can install what you need via the package manager tlmgr using the minimal distribution, basictex. Which is still hundreds of megabytes, but we are going to have to take what breaks we can here. Then you take the bare bones setup and install the extra things you need.
For example, to render jupyter notebooks, you’ll need:
tlmgr install \
collectbox \
collection-fontsrecommended \
enumitem \
logreq \
ucs \
xstring
To handle fancier jupyter notebook via ipypublish, we also need
tlmgr install \
latexmk \
translations
To handle biblatex:
tlmgr install biblatex
To handle modern referencing:
tlmgr install placeins \
todonotes \
chngcntr \
doi \
mdframed \
needspace \
cleveref
To handle pandoc:
tlmgr install biblatex \
biber \
xstring \
logreq
To handle Anki flashcard rendering:
tlmgr install bbm-macros \
dvipng
To handle latex_fragment:
tlmgr install standalone \
preview
To handle .eps files.
tlmgr install epstopdf
To handle Tom Pollard’s markdown thesis:
tlmgr install truncate \
tocloft \
wallpaper \
morefloats \
sectsty \
siunitx \
threeparttable \
l3packages \
l3kernel \
l3experimental
You keep it up to date in a the obvious way:
tlmgr update --self
tlmgr update --all
The non-obvious thing is that this works for approximately one year, then you are cut off from updates, and have to do a crazy tedious procedure to get another year’s life out of TeX.
No TeX at all
You just want equations? You don’t need TeX-the-software, just TeX-the-markup. Lots of things can render TeX math.
Editors
• Mathematica can export mathematics to TeX and is a good, if collossally overengineered, editor
• TeXStudio has image drag-n-drop support
• latex-workshop is the VS Code LaTeX extension. It’s slick, although overeager to try and typeset every document you open.
• atom-latex and the atom latex package both bring LaTeX support to the Atom editor though I haven’t yet worked out the difference. The latter supports literate coding so is morally superior.
• texshop is the open-source stalwart editor on e.g. OSX.
• TeXmacs - if you want to integrate a beautiful but obscure and poorly maintained notebook-style interface with your typesetting. Many do. I’d rather use knitr etc for integrating my diagrams and keep the GUIs separate, but this is personal preference.
Posters
a0poster is popular, as expounded by Morales de Luna, but I secretly feel that it sounds like a nightmare of legacy postscript nonsense and doesn’t even look good. sciposter is a popular a0poster variant.
tikzposter and beamerposter are both highlighted on sharelatex and are truly fugly. Why would anyone who claims to care about design inflict this on the world?
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https://wikimili.com/en/Newton's_cradle
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Last updated
The Newton's cradle is a device that demonstrates the conservation of momentum and the conservation of energy with swinging spheres. When one sphere at the end is lifted and released, it strikes the stationary spheres, transmitting a force through the stationary spheres that pushes the last sphere upward. The last sphere swings back and strikes the nearly stationary spheres, repeating the effect in the opposite direction. The device is named after 17th-century English scientist Sir Isaac Newton and designed by French scientist Edme Mariotte. It is also known as Newton's pendulum, Newton's balls, Newton's rocker or executive ball clicker (since the device makes a click each time the balls collide, which they do repeatedly in a steady rhythm). [1] [2]
## Operation
When one of the end balls ("the first") is pulled sideways, the attached string makes it follow an upward arc. When it is let go, it strikes the second ball and comes to nearly a dead stop. The ball on the opposite side acquires most of the velocity of the first ball and swings in an arc almost as high as the release height of the first ball. This shows that the last ball receives most of the energy and momentum of the first ball. The impact produces a compression wave that propagates through the intermediate balls. Any efficiently elastic material such as steel does this, as long as the kinetic energy is temporarily stored as potential energy in the compression of the material rather than being lost as heat. There are slight movements in all the balls after the initial strike but the last ball receives most of the initial energy from the impact of the first ball. When two (or three) balls are dropped, the two (or three) balls on the opposite side swing out. Some say that this behavior demonstrates the conservation of momentum and kinetic energy in elastic collisions. However, if the colliding balls behave as described above with the same mass possessing the same velocity before and after the collisions, then any function of mass and velocity is conserved in such an event. [3]
## Physics explanation
Newton's cradle can be modeled fairly accurately with simple mathematical equations with the assumption that the balls always collide in pairs. If one ball strikes four stationary balls that are already touching, these simple equations can not explain the resulting movements in all five balls, which are not due to friction losses. For example, in a real Newton's cradle the fourth has some movement and the first ball has a slight reverse movement. All the animations in this article show idealized action (simple solution) that only occurs if the balls are not touching initially and only collide in pairs.
### Simple solution
The conservation of momentum (mass × velocity) and kinetic energy (1/2 × mass × velocity2) can be used to find the resulting velocities for two colliding perfectly elastic objects. These two equations are used to determine the resulting velocities of the two objects. For the case of two balls constrained to a straight path by the strings in the cradle, the velocities are a single number instead of a 3D vector for 3D space, so the math requires only two equations to solve for two unknowns. When the two objects weigh the same, the solution is simple: the moving object stops relative to the stationary one and the stationary one picks up all the other's initial velocity. This assumes perfectly elastic objects, so there is no need to account for heat and sound energy losses.
Steel does not compress much, but its elasticity is very efficient, so it does not cause much waste heat. The simple effect from two same-weight efficiently elastic colliding objects constrained to a straight path is the basis of the effect seen in the cradle and gives an approximate solution to all its activities.
For a sequence of same-weight elastic objects constrained to a straight path, the effect continues to each successive object. For example, when two balls are dropped to strike three stationary balls in a cradle, there is an unnoticed but crucial small distance between the two dropped balls, and the action is as follows: the first moving ball that strikes the first stationary ball (the second ball striking the third ball) transfers all its velocity to the third ball and stops. The third ball then transfers the velocity to the fourth ball and stops, and then the fourth to the fifth ball. Right behind this sequence is the second moving ball transferring its velocity to the first moving ball that just stopped, and the sequence repeats immediately and imperceptibly behind the first sequence, ejecting the fourth ball right behind the fifth ball with the same small separation that was between the two initial striking balls. If they are simply touching when they strike the third ball, precision requires the more complete solution below.
#### Other examples of this effect
The effect of the last ball ejecting with a velocity nearly equal to the first ball can be seen in sliding a coin on a table into a line of identical coins, as long as the striking coin and its twin targets are in a straight line. The effect can similarly be seen in billiard balls. The effect can also be seen when a sharp and strong pressure wave strikes a dense homogeneous material immersed in a less-dense medium. If the identical atoms, molecules, or larger-scale sub-volumes of the dense homogeneous material are at least partially elastically connected to each other by electrostatic forces, they can act as a sequence of colliding identical elastic balls. The surrounding atoms, molecules, or sub-volumes experiencing the pressure wave act to constrain each other similarly to how the string constrains the cradle's balls to a straight line. For example, lithotripsy shock waves can be sent through the skin and tissue without harm to burst kidney stones. The side of the stones opposite to the incoming pressure wave bursts, not the side receiving the initial strike.
#### When the simple solution applies
For the simple solution to precisely predict the action, no pair in the midst of colliding may touch the third ball, because the presence of the third ball effectively makes the struck ball appear heavier. Applying the two conservation equations to solve the final velocities of three or more balls in a single collision results in many possible solutions, so these two principles are not enough to determine resulting action.
Even when there is a small initial separation, a third ball may become involved in the collision if the initial separation is not large enough. When this occurs, the complete solution method described below must be used.
Small steel balls work well because they remain efficiently elastic with little heat loss under strong strikes and do not compress much (up to about 30 μm in a small Newton's cradle). The small, stiff compressions mean they occur rapidly, less than 200 microseconds, so steel balls are more likely to complete a collision before touching a nearby third ball. Softer elastic balls require a larger separation to maximize the effect from pair-wise collisions.
### More complete solution
A cradle that best follows the simple solution needs to have an initial separation between the balls that measures at least twice the amount that any one ball compresses, but most do not. This section describes the action when the initial separation is not enough and in subsequent collisions that involve more than two balls even when there is an initial separation. This solution simplifies to the simple solution when only two balls touch during a collision. It applies to all perfectly elastic identical balls that have no energy losses due to friction and can be approximated by materials such as steel, glass, plastic, and rubber.
For two balls colliding, only the two equations for conservation of momentum and energy are needed to solve the two unknown resulting velocities. For three or more simultaneously colliding elastic balls, the relative compressibilities of the colliding surfaces are the additional variables that determine the outcome. For example, five balls have four colliding points and scaling (dividing) three of them by the fourth gives the three extra variables needed to solve for all five post-collision velocities.
Newtonian, Lagrangian, Hamiltonian, and stationary action are the different ways of mathematically expressing classical mechanics. They describe the same physics but must be solved by different methods. All enforce the conservation of energy and momentum. Newton's law has been used in research papers. It is applied to each ball and the sum of forces is made equal to zero. So there are five equations, one for each ball—and five unknowns, one for each velocity. If the balls are identical, the absolute compressibility of the surfaces becomes irrelevant, because it can be divided out of both sides of all five equations, producing zero.
Determining the velocities [4] [5] [6] for the case of one ball striking four initially-touching balls is found by modeling the balls as weights with non-traditional springs on their colliding surfaces. Most materials, like steel, that are efficiently elastic approximately follow Hooke's force law for springs, ${\displaystyle F=k\cdot x}$, but because the area of contact for a sphere increases as the force increases, colliding elastic balls follow Hertz's adjustment to Hooke's law, ${\displaystyle F=k\cdot x^{1.5}}$. This and Newton's law for motion (${\displaystyle F=m\cdot a}$) are applied to each ball, giving five simple but interdependent differential equations that are solved numerically. When the fifth ball begins accelerating, it is receiving momentum and energy from the third and fourth balls through the spring action of their compressed surfaces. For identical elastic balls of any type with initially touching balls, the action is the same for the first strike, except the time to complete a collision increases in softer materials. 40% to 50% of the kinetic energy of the initial ball from a single-ball strike is stored in the ball surfaces as potential energy for most of the collision process. Thirteen percent of the initial velocity is imparted to the fourth ball (which can be seen as a 3.3-degree movement if the fifth ball moves out 25 degrees) and there is a slight reverse velocity in the first three balls, the first ball having the largest at −7% of the initial velocity. This separates the balls, but they come back together just before as the fifth ball returns. This is due to the pendulum phenomenon of different small angle disturbances having approximately the same time to return to the center. When balls are "touching" in subsequent collisions is complex, but still determinable by this method, especially if friction losses are included and the pendulum timing is calculated exactly instead of relying on the small angle approximation.
The differential equations with the initial separations are needed if there is less than 10 μm separation when using 100-gram steel balls with an initial 1 m/s strike speed.
The Hertzian differential equations predict that if two balls strike three, the fifth and fourth balls will leave with velocities of 1.14 and 0.80 times the initial velocity. [7] This is 2.03 times more kinetic energy in the fifth ball than the fourth ball, which means the fifth ball would swing twice as high in the vertical direction as the fourth ball. But in a real Newton's cradle, the fourth ball swings out as far as the fifth ball. To explain the difference between theory and experiment, the two striking balls must have at least ≈10 μm separation (given steel, 100 g, and 1 m/s). This shows that in the common case of steel balls, unnoticed separations can be important and must be included in the Hertzian differential equations, or the simple solution gives a more accurate result.
### Effect of pressure waves
The forces in the Hertzian solution above were assumed to propagate in the balls immediately, which is not the case. Sudden changes in the force between the atoms of material build up to form a pressure wave. Pressure waves (sound) in steel travel about 5 cm in 10 microseconds, which is about 10 times faster than the time between the first ball striking and the last ball being ejected. The pressure waves reflect back and forth through all five balls about ten times, although dispersing to less of a wavefront with more reflections. This is fast enough for the Hertzian solution to not require a substantial modification to adjust for the delay in force propagation through the balls. In less-rigid but still very elastic balls such as rubber, the propagation speed is slower, but the duration of collisions is longer, so the Hertzian solution still applies. The error introduced by the limited speed of the force propagation biases the Hertzian solution towards the simple solution because the collisions are not affected as much by the inertia of the balls that are further away.
Identically-shaped balls help the pressure waves converge on the contact point of the last ball: at the initial strike point one pressure wave goes forward to the other balls while another goes backward to reflect off the opposite side of the first ball, and then it follows the first wave, being exactly 1 ball-diameter behind. The two waves meet up at the last contact point because the first wave reflects off the opposite side of the last ball and it meets up at the last contact point with the second wave. Then they reverberate back and forth like this about 10 times until the first ball stops connecting with the second ball. Then the reverberations reflect off the contact point between the second and third balls, but still converge at the last contact point, until the last ball is ejected—but it is less of a wavefront with each reflection.
### Effect of different types of balls
Using different types of material does not change the action as long as the material is efficiently elastic. The size of the spheres does not change the results unless the increased weight exceeds the elastic limit of the material. If the solid balls are too large, energy is being lost as heat, because the elastic limit increases with the radius raised to the power 1.5, but the energy which had to be absorbed and released increases as the cube of the radius. Making the contact surfaces flatter can overcome this to an extent by distributing the compression to a larger amount of material but it can introduce an alignment problem. Steel is better than most materials because it allows the simple solution to apply more often in collisions after the first strike, its elastic range for storing energy remains good despite the higher energy caused by its weight, and the higher weight decreases the effect of air resistance.
## Uses
The most common application is that of a desktop executive toy. Another use is as an educational physics demonstration, as an example of conservation of momentum and conservation of energy. A similar principle, the propagation of waves in solids, was used in the Constantinesco Synchronization gear system for propeller / gun synchronizers on early fighter aircraft.[ further explanation needed ]
## History
Christiaan Huygens used pendulums to study collisions. His work, De Motu Corporum ex Percussione (On the Motion of Bodies by Collision) published posthumously in 1703, contains a version of Newton's first law and discusses the collision of suspended bodies including two bodies of equal mass with the motion of the moving body being transferred to the one at rest.
The principle demonstrated by the device, the law of impacts between bodies, was first demonstrated by the French physicist Abbé Mariotte in the 17th century. [1] [8] Newton acknowledged Mariotte's work, among that of others, in his Principia .
There is much confusion over the origins of the modern Newton's cradle. Marius J. Morin has been credited as being the first to name and make this popular executive toy.[ citation needed ] However, in early 1967, an English actor, Simon Prebble, coined the name "Newton's cradle" (now used generically) for the wooden version manufactured by his company, Scientific Demonstrations Ltd. [9] After some initial resistance from retailers, they were first sold by Harrods of London, thus creating the start of an enduring market for executive toys.[ citation needed ] Later a very successful chrome design for the Carnaby Street store Gear was created by the sculptor and future film director Richard Loncraine.[ citation needed ]
The largest cradle device in the world was designed by MythBusters and consisted of five one-ton concrete and steel rebar-filled buoys suspended from a steel truss. [10] The buoys also had a steel plate inserted in between their two-halves to act as a "contact point" for transferring the energy; this cradle device did not function well because concrete is not elastic so most of the energy was lost to a heat buildup in the concrete. A smaller scale version constructed by them consists of five 15-centimetre (6 in) chrome steel ball bearings, each weighing 15 kilograms (33 lb), and is nearly as efficient as a desktop model.
The cradle device with the largest diameter collision balls on public display was visible for more than a year in Milwaukee, Wisconsin, at the retail store American Science and Surplus (see photo). Each ball was an inflatable exercise ball 66 cm (26 in) in diameter (encased in steel rings), and was supported from the ceiling using extremely strong magnets. It was dismantled in early August 2010 due to maintenance concerns.[ citation needed ]
Newton's cradle has been used more than 20 times in movies, [11] often as a trope on the desk of a lead villain such as Paul Newman's role in The Hudsucker Proxy, Magneto in X-Men, and the Kryptonians in Superman II. It was used to represent the unyielding position of the NFL towards head injuries in Concussion. [12] It has also been used as a relaxing diversion on the desk of lead intelligent/anxious/sensitive characters such as Henry Winkler's role in Night Shift, Dustin Hoffman's role in Straw Dogs, and Gwyneth Paltrow's role in Iron Man 2. It was featured more prominently as a series of clay pots in Rosencrantz and Guildenstern Are Dead , and as a row of 1968 Eero Aarnio bubble chairs with scantily-clad women in them in Gamer. [13] In Storks , Hunter the CEO of Cornerstore has one not with balls, but with little birds. Newton’s Cradle is an item in Nintendo’s Animal Crossing where it is referred to as “executive toy”. [14] In 2017, an episode of the Omnibus podcast, featuring Jeopardy! champion Ken Jennings and musician John Roderick, focused on the history of Newton's Cradle. [15] Newton's cradle is also featured on the desk of Deputy White House Communications Director Sam Seaborn in The West Wing .
Rock band Jefferson Airplane used the cradle on the 1968 album Crown of Creation as a rhythm device to create polyrhythms on an instrumental track.
## Related Research Articles
In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids—liquids and gases. It has several subdisciplines, including aerodynamics and hydrodynamics. Fluid dynamics has a wide range of applications, including calculating forces and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation.
In Newtonian mechanics, linear momentum, translational momentum, or simply momentum is the product of the mass and velocity of an object. It is a vector quantity, possessing a magnitude and a direction. If m is an object's mass and v is its velocity, then the object's momentum is
In physics, mathematics, and related fields, a wave is a propagating dynamic disturbance of one or more quantities, sometimes as described by a wave equation. In physical waves, at least two field quantities in the wave medium are involved. Waves can be periodic, in which case those quantities oscillate repeatedly about an equilibrium (resting) value at some frequency. When the entire waveform moves in one direction it is said to be a traveling wave; by contrast, a pair of superimposed periodic waves traveling in opposite directions makes a standing wave. In a standing wave, the amplitude of vibration has nulls at some positions where the wave amplitude appears smaller or even zero.
In physics, a collision is any event in which two or more bodies exert forces on each other in a relatively short time. Although the most common use of the word collision refers to incidents in which two or more objects collide with great force, the scientific use of the term implies nothing about the magnitude of the force.
An elastic collision is an encounter between two bodies in which the total kinetic energy of the two bodies remains the same. In an ideal, perfectly elastic collision, there is no net conversion of kinetic energy into other forms such as heat, noise, or potential energy.
An inelastic collision, in contrast to an elastic collision, is a collision in which kinetic energy is not conserved due to the action of internal friction.
In physics, equations of motion are equations that describe the behavior of a physical system in terms of its motion as a function of time. More specifically, the equations of motion describe the behavior of a physical system as a set of mathematical functions in terms of dynamic variables. These variables are usually spatial coordinates and time, but may include momentum components. The most general choice are generalized coordinates which can be any convenient variables characteristic of the physical system. The functions are defined in a Euclidean space in classical mechanics, but are replaced by curved spaces in relativity. If the dynamics of a system is known, the equations are the solutions for the differential equations describing the motion of the dynamics.
In classical mechanics, impulse is the integral of a force, F, over the time interval, t, for which it acts. Since force is a vector quantity, impulse is also a vector quantity. Impulse applied to an object produces an equivalent vector change in its linear momentum, also in the resultant direction. The SI unit of impulse is the newton second (N⋅s), and the dimensionally equivalent unit of momentum is the kilogram meter per second (kg⋅m/s). The corresponding English engineering unit is the pound-second (lbf⋅s), and in the British Gravitational System, the unit is the slug-foot per second (slug⋅ft/s).
In physics, action is a numerical value describing how a physical system has changed over time. Action is significant because the equations of motion of the system can be derived through the principle of stationary action. In the simple case of a single particle moving with a specified velocity, the action is the momentum of the particle times the distance it moves, added up along its path, or equivalently, twice its kinetic energy times the length of time for which it has that amount of energy, added up over the period of time under consideration. For more complicated systems, all such quantities are added together. More formally, action is a mathematical functional which takes the trajectory, also called path or history, of the system as its argument and has a real number as its result. Generally, the action takes different values for different paths. Action has dimensions of energy × time or momentum × length, and its SI unit is joule-second.
The Kerr metric or Kerr geometry describes the geometry of empty spacetime around a rotating uncharged axially-symmetric black hole with a quasispherical event horizon. The Kerr metric is an exact solution of the Einstein field equations of general relativity; these equations are highly non-linear, which makes exact solutions very difficult to find.
In solid-state physics crystal momentum or quasimomentum is a momentum-like vector associated with electrons in a crystal lattice. It is defined by the associated wave vectors of this lattice, according to
In general relativity, an exact solution is solution of the Einstein field equations whose derivation does not invoke simplifying assumptions, though the starting point for that derivation may be an idealized case like a perfectly spherical shape of matter. Mathematically, finding an exact solution means finding a Lorentzian manifold equipped with tensor fields modeling states of ordinary matter, such as a fluid, or classical non-gravitational fields such as the electromagnetic field.
The coefficient of restitution, is the ratio of the final to initial relative speed between two objects after they collide. It normally ranges from 0 to 1 where 1 would be a perfectly elastic collision. A perfectly inelastic collision has a coefficient of 0, but a 0 value does not have to be perfectly inelastic. It is measured in the Leeb rebound hardness test, expressed as 1000 times the COR, but it is only a valid COR for the test, not as a universal COR for the material being tested.
The physicist Sir Isaac Newton first developed this idea to get rough approximations for the impact depth for projectiles traveling at high velocities.
Soft-body dynamics is a field of computer graphics that focuses on visually realistic physical simulations of the motion and properties of deformable objects. The applications are mostly in video games and films. Unlike in simulation of rigid bodies, the shape of soft bodies can change, meaning that the relative distance of two points on the object is not fixed. While the relative distances of points are not fixed, the body is expected to retain its shape to some degree. The scope of soft body dynamics is quite broad, including simulation of soft organic materials such as muscle, fat, hair and vegetation, as well as other deformable materials such as clothing and fabric. Generally, these methods only provide visually plausible emulations rather than accurate scientific/engineering simulations, though there is some crossover with scientific methods, particularly in the case of finite element simulations. Several physics engines currently provide software for soft-body simulation.
Lamb waves propagate in solid plates or spheres. They are elastic waves whose particle motion lies in the plane that contains the direction of wave propagation and the plane normal. In 1917, the English mathematician Horace Lamb published his classic analysis and description of acoustic waves of this type. Their properties turned out to be quite complex. An infinite medium supports just two wave modes traveling at unique velocities; but plates support two infinite sets of Lamb wave modes, whose velocities depend on the relationship between wavelength and plate thickness.
A Galilean cannon is a device that demonstrates conservation of linear momentum. It comprises a stack of balls, starting with a large, heavy ball at the base of the stack and progresses up to a small, lightweight ball at the top. The basic idea is that this stack of balls can be dropped to the ground and almost all of the kinetic energy in the lower balls will be transferred to the topmost ball - which will rebound to many times the height from which it was dropped. At first sight, the behavior seems highly counter-intuitive, but in fact is precisely what conservation of momentum predicts. The principal difficulty is in keeping the configuration of the balls stable during the initial drop. Early descriptions involve some sort of glue/tape, tube, or net to align the balls.
The index of physics articles is split into multiple pages due to its size.
The physics of a bouncing ball concerns the physical behaviour of bouncing balls, particularly its motion before, during, and after impact against the surface of another body. Several aspects of a bouncing ball's behaviour serve as an introduction to mechanics in high school or undergraduate level physics courses. However, the exact modelling of the behaviour is complex and of interest in sports engineering.
## References
1. "Newton's Cradle". Harvard Natural Sciences Lecture Demonstrations. Harvard University. 27 February 2019.
2. Palermo, Elizabeth (28 August 2013). "How Does Newton's Cradle Work?". Live Science.
3. Gauld, Colin F. (August 2006). "Newton's Cradle in Physics Education". Science & Education. 15 (6): 597–617. Bibcode:2006Sc&Ed..15..597G. doi:10.1007/s11191-005-4785-3. S2CID 121894726.
4. Herrmann, F.; Seitz, M. (1982). "How does the ball-chain work?" (PDF). American Journal of Physics. 50. pp. 977–981. Bibcode:1982AmJPh..50..977H. doi:10.1119/1.12936.
5. Lovett, D. R.; Moulding, K. M.; Anketell-Jones, S. (1988). "Collisions between elastic bodies: Newton's cradle". European Journal of Physics. 9 (4): 323. Bibcode:1988EJPh....9..323L. doi:10.1088/0143-0807/9/4/015.
6. Hutzler, Stefan; Delaney, Gary; Weaire, Denis; MacLeod, Finn (2004). "Rocking Newton's Cradle" (PDF). American Journal of Physics. 72. pp. 1508–1516. Bibcode:2004AmJPh..72.1508H. doi:10.1119/1.1783898.C F Gauld (2006), Newton's cradle in physics education, Science & Education, 15, 597–617
7. Hinch, E.J.; Saint-Jean, S. (1999). "The fragmentation of a line of balls by an impact" (PDF). Proc. R. Soc. Lond. A. 455. pp. 3201–3220.
8. Schulz, Chris (17 January 2012). "How Newton's Cradles Work". HowStuffWorks. Retrieved 27 February 2019.
9. Concussion – Cinemaniac Reviews Archived 11 February 2017 at the Wayback Machine
10. Animal Crossing Official Game Guide by Nintendo Power. Nintendo.
## Literature
• Herrmann, F. (1981). "Simple explanation of a well-known collision experiment". American Journal of Physics. 49 (8): 761. Bibcode:1981AmJPh..49..761H. doi:10.1119/1.12407.
• B. Brogliato: Nonsmooth Mechanics. Models, Dynamics and Control, Springer, 2nd Edition, 1999.
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https://ncertmcq.com/rs-aggarwal-class-9-solutions-chapter-14-statistics-ex-14a/
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RS Aggarwal Class 9 Solutions Chapter 14 Statistics Ex 14A
These Solutions are part of RS Aggarwal Solutions Class 9. Here we have given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14A.
Other Exercises
Question 1.
Solution:
Statistics is a science which deals with the collection, presentation, analysis and interpretations of numerical data.
Question 2.
Solution:
(i) Numerical facts alone constitute data
(ii) Qualitative characteristics like intelligence, poverty etc. which cannot be measured, numerically, don’t form data.
(iii) Data are an aggregate of facts. A single observation does not form data.
(iv) Data collected for a definite purpose may not be suited for another purpose.
(v) Data is different experiments are comparable.
Question 3.
Solution:
(i) Primary data : The data collected by the investigator himself with a definite plan in mind are called primary data.
(ii) Secondary data : The data collected by some one other than the investigator are called secondary data. The primary data is more reliable and relevant.
Question 4.
Solution:
(i) Variate : Any character which is capable of taking several different values is called a variate or variable.
(ii) Class interval : Each group into which the raw data is condensed, is called a class interval
(iii) Class size : The difference between the true upper limit and the true lower limit of a class is called class size.
(iv) Class Mark : $$\frac { upper\quad limit+lower\quad limit }{ 2 }$$ is called a class mark
(v) Class limits : Each class is bounded by two figures which are called class limits which are lower class limit and upper class limit.
(vi) True class limits : In exclusive form, the upper and lower limits of a class are respectively are the true upper limit and true lower limit but in inclusive form, the true lower limit of a class is obtained by subtracting O.S from lower limit of the class and for true limit, adding 0.5 to the upper limit.
(vii) Frequency of a class : The number of times an observation occurs in a class is called its frequency.
(viii) Cumulative frequency of a class : The cumulative frequency corresponding to a class is the sum of all frequencies upto and including that class.
Question 5.
Solution:
The given data can be represent in form of frequency table as given below:
Question 6.
Solution:
The frequency distribution table of the given data is given below :
Question 7.
Solution:
The frequency distribution table of the
Question 8.
Solution:
The frequency table is given below :
Question 9.
Solution:
The frequency table of given data is given below :
Question 10.
Solution:
The frequency distribution table of the given data in given below :
Question 11.
Solution:
The frequency table of the given data:
Question 12.
Solution:
The cumulative frequency of the given table is given below:
Question 13.
Solution:
The given table can be represented in a group frequency table in given below :
Question 14.
Solution:
Frequency table of the given cumulative frequency is given below :
Question 15.
Solution:
A frequency table of the given cumulative frequency table is given below :
Hope given RS Aggarwal Solutions Class 9 Chapter 14 Statistics Ex 14A are helpful to complete your math homework.
If you have any doubts, please comment below. Learn Insta try to provide online math tutoring for you.
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https://arxiv-export-lb.library.cornell.edu/abs/2206.15251
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cs.DM
(what is this?)
# Title: Menger's Theorem for Temporal Paths (Not Walks)
Abstract: A temporal graph is a graph whose edges are available only at specific times. In this scenario, the only valid walks are the ones traversing adjacent edges respecting their availability, i.e. sequence of adjacent edges whose appearing times are non-decreasing. Temporal paths are temporal walks where each vertex is not traversed twice, i.e. time instants of each vertex, called temporal vertices, are visited consecutively. While on static graphs Menger's Theorem relies on disjoint paths, in temporal graphs the literature has focused on disjoint temporal walks. In this paper we focus on Menger's Theorem for temporal paths that are disjoint in temporal vertices. Given two vertices $s$ and $t$, let $k$ be equal to the maximum number of temporal vertex disjoint $s,t$-paths. We prove that $k$ is equal to the minimum number of temporal vertices to be removed to break all the $s,t$-paths, i.e. Menger's Theorem holds, if and only if $k=1$. The latter property also allows us to show that the related max-paths problem in temporal graphs is polynomial when $k\le 2$. This is best possible as we prove that such problem is \NP-hard when $k\ge 3$ for the directed case. Finally, we also give hardness results and an XP algorithm for the related min-cut problem.
Subjects: Discrete Mathematics (cs.DM); Combinatorics (math.CO) Cite as: arXiv:2206.15251 [cs.DM] (or arXiv:2206.15251v1 [cs.DM] for this version)
## Submission history
From: Ana Silva [view email]
[v1] Thu, 30 Jun 2022 12:57:52 GMT (694kb,D)
Link back to: arXiv, form interface, contact.
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https://mathoverflow.net/questions/211746/a-question-on-representation-of-graphs
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# A question on representation of graphs
Take a complete graph $K_n$. You want to assign a vectors from $\Bbb F_2^d$ to every edge such that sum of vectors in every simple cycle does not sum to $0$ vector. The question is what is minimum $d$ that is needed. Does this question have any connection to representation of symmetric group over $\Bbb F_2^d$?
Update: Fundamental roadblock here seems to be related to finding a nice way to provide labelling that encompasses every even alternating/reverse alternating cycle which prevents a better than $O(n\log{n})$ solution.
ADDED by David Speyer: I'd like to explain why I find this question interesting and challenging, and wish that people better at extremal combinatorics had turned some attention to it.
If we instead ask that every disjoint union of simple cycles have nonzero sum, the problem is easy (at least to leading order). A winning strategy is to use $d=n \log_2 n$ bits, divided into $n$ blocks of length $\log_2 n$. For edge $ij$, put the binary label of $j$ in the $i$-th block and the binary label of $j$ in the $i$-th block. And it is easy to show you can't do much better. For simplicity, take $n=2m$ even. Look at the $(2m-1) (2m-3) \cdots 5 \cdot 3 \cdot 1$ perfect matchings of the graph. If any two of them get the same sum, then their symmetric difference is a disjoint union of cycles with weight $0$. So we need to have at least $(2m-1) (2m-3) \cdots 5 \cdot 3 \cdot 1$ different vectors, so we need to use at least $\log_2 (2m-1) (2m-3) \cdots 5 \cdot 3 \cdot 1 \approx \frac{n}{2} \log_2 n$ bits. We have found the answer up to a factor of $2$.
Now, out of the $n!$ disjoint unions of cycles, roughly $(e/n) n!$ are a single cycle. One would think that reducing the number of things to avoid by a factor of $n$ shouldn't be able to effect the number of bits very much. Yet it seems incredibly hard to show this! How can we show that the cycles are basically randomly distributed among the disjoint unions of cycles?
Here is one way we could attempt to give a lower bound. Once again, take $n=2m$. Look at the $m!$ matchings from the first $m$ vertices to the second, which we can identify with the group $S_m$. Adding up the edges in a matching gives a coloring of $S_m$ with $2^d$ colors. If we make $S_m$ into a graph by joining $\sigma$ and $\tau$ when $\sigma^{-1} \tau$ is a single cycle, then this must be a proper coloring. So we are trying to find a lower bound for the chromatic number of the Cayley graph of $S_m$ with respect to the cycles. There is literature on the chromatic number of Cayley graphs, but I couldn't find anything that would help. I did find that a random graph on $m!$ vertices where an edge would appear with probability $e/m$ should be expected to have chromatic number $\frac{m! (e/m)}{2 \log m!} \approx \frac{e m!}{2 m^2 \log m}$. If that is the case here, we once again get $d \geq \log_2 m!$ (discarding lower terms). Is there some $S_m$ representation theory which would allow us to actually compute the chromatic number?
It really frustrates me that there is an exponential separation between by upper and lower bounds.
I will give the bounty for a construction which beats $(1-\delta) n \log_2 n$, or a lower bound which beats $(\log n)^{1+\delta}$, for any $\delta>0$.
Finally, I'd like to share a wild musing of mine. Consider two problems in graph theory and optimization. In the first problem, we are given an $n \times n$ matrix of weights $w_{ij}$, and we are trying to find a permuation $\sigma$ of $n$ which minimizes $\sum_i w_{i \sigma(i)}$. The second problem is the same, but we require that $\sigma$ is an $n$-cycle. The first problem is the assignment problem and there are good algorithms for it. The second problem is the traveling salesman problem and it is NP Hard. I am reminded of this problem: A large fraction of permutations are cycles, yet restricting myself to cycles makes thing incredibly harder.
• I do not think the tag representation theory is a proper one here. – Alireza Abdollahi Jul 17 '15 at 7:03
• @AlirezaAbdollahi Actually I do not know. I think this question may have a connection. – Brout Jul 17 '15 at 10:39
• I see. Maybe a the graph-theory tag is needed. – Alireza Abdollahi Jul 17 '15 at 11:37
• Tossed in coding-theory tag. Here is my thinking: Let $V$ be the free vector space on the $\binom{n}{2}$ edges of your graph. Let $K$ be the kernel of the map $V \to \mathbb{F}_2^d$ given by your labels. You want $K$ to be large while not containing the characteristic function of any cycle. This reminds me of the coding theory goal of finding large $K$ that does not contain any vector of small Hamming weight. – David E Speyer Jul 21 '15 at 3:43
• @DavidSpeyer: maybe you could come up with a more evocative title for this question? – Sam Hopkins Jul 27 '15 at 3:11
It's important to clarify what definition of "cycle" you have in mind. In algebraic-graph-theory contexts like this one, the natural definition is that it's a set of edges with even degree at each vertex; these sets form the vectors of a $\mathbb{Z}_2$-vector space, the cycle space of the graph, using the symmetric difference operation as the vector sum.
With this definition, the minimum $d$ you're looking for is just the circuit rank of the graph, i.e. the dimension of the cycle space, $m-n+1$ where $m$ is the number of edges and $n$ is the number of vertices. Your labeling gives a linear map from the cycle space to the label space, this map has a nontrivial kernel unless $d$ is large enough, and a vector in the kernel is a cycle with zero label sum. In the other direction, it is easy to find labelings with dimension equal to the circuit rank that avoid cycles summing to zero. For instance, find a spanning tree of the graph, label each tree edge with the zero vector, and label each non-tree edge with a basis vector (independent of all the other nonzero labels).
This all works regardless of whether the graph is complete. But if you have some other definition of cycles in mind, such as simple cycles, then your labeling problem looks messier.
• No, the cycle basis article is about a different (non-algebraic) invariant of directed graphs. – David Eppstein Jul 17 '15 at 16:00
I have now tried a few different strategies which are all winding up at $d \approx n \log_2 n$. I'll describe the simplest of these. (David Epstein's strategy with the spanning tree gives $d \approx n^2/2$.)
Let $2^{m-1} < n \leq 2^m$, so we can encode the vertices of the graph with $m$ bits. I will show how to take $d=mn$. Think of those $mn$ bits as $n$ blocks of length $m$. For an edge joining vertices $i$ and $j$, put the binary label of $j$ in the $i$-th block and the binary label of $i$ in the $j$-th block. Put zeroes in all other blocks.
Suppose we have a simple cycle. Let this cycle contain the section $(i,j,k)$. Then the $j$-th block will contain the binary labels of $i$ and $k$, which will not cancel, and nothing else.
I have some minor tricks which can shave small numbers of bits off this, but I am waiting to see if someone can come up with something much better first.
My best lower bound is $\approx \log_2 n$. This is horribly far from what I believe the truth to be, but I record it nonetheless. Let $n=2p$ for $p$ prime. For $0 \leq k < p$, let $w_k = \sum_{i=1}^p v(i, p+1+(i \bmod p))$. If $d < \log_2 p$, then two of the $w_k$ are equal by the pigeonhole principle, say $w_{k_1} = w_{k_2}$. But then $w_{k_1} + w_{k_2}$ is the sum over the edges in a $2p$ cycle.
• As a heuristic, there are about $n!$ simple cycles in $K_n$. If we want to get $d$ below $\log_2 n! \approx n \log_2 n$, we need to get the images of the simple cycles in $\mathbb{F}_2^d$ to be abnormally skewed away from $0$. It is easy to think of weights that skew towards zero, but hard to find ways to skew away. – David E Speyer Jul 21 '15 at 4:45
• Apparently so. I can't prove any lower bounds, which is frustrating, but there are upwards of $(2^n)!$ simple cycles which only use edges between the two graphs. It doesn't surprise me that I need something like $2^n$ more coordinates to kill them all. – David E Speyer Jul 21 '15 at 6:44
• I don't understand what ring structure you want to use on $\mathbb{F}_2^d$ for this strategy, nor particularly why you think these quadratic equations will be easier to make nonzero than the linear ones you started with. Assuming that you are using the finite field of order $2^d$, and arguing heuristically, there are $2^{nd}$ possible choices of the $x_i$. Each quadratic vanishes at about $1/2$ these choices, and there are $\approx n!$ quadratics. (continued) – David E Speyer Jul 21 '15 at 12:06
• So I would expect odds of success for an individual choice to be $1/2^{n!}$. So I expect to win if $2^{nd}/2^{n!}>1$, or $d \approx n!$. This is much worse than the $\log_2 n!$ I gave above. Do you have a reason to think you can do better than random? – David E Speyer Jul 21 '15 at 12:06
• Why? (Plus more characters.) – David E Speyer Jul 21 '15 at 12:09
Here is a modest improvement on the upper bound that shows $d=O(n\log\log n)$.
The base of the construction is the following. Order the vertices according to some permutation as $v_1,\ldots,v_n$. Fix $2n$ independent vectors from $\mathbb F_2^d$ and assign two vectors, $\ell_i$ and $r_i$, to each vertex $v_i$. Assign to the edge $v_iv_j$ the vector $r_i+\ell_j$ if $i<j$ and $\ell_i+r_j$ if $i>j$. Notice that this usually gives a nonzero sum for long cycles.
Our strategy will be to take $t\approx \log \frac nk$ permutations (with $t\cdot 2n$ independent vectors) and take the sums on each edge to take care of all cycles longer than $k$. The standard probabilistic approach with $\approx k\log n$ further independent vectors takes care of all cycles whose length is at most $k$. This in total gives $d\approx t\cdot n + k\log n =O(n\log\log n)$.
Claim. $t\approx \log \frac nk$ permutations are enough to take care of all cycles longer than $k$.
Proof of the claim. Divide $n$ into groups of size $k$. Fix an order inside each group, this will be the same in each permutation, which thus practically act on $m=\frac nk$ elements. For every cycle $C=c_1\ldots c_k$ of length $k$, either there are three different groups that contain three consecutive vertices from $C$ (thus $c_{i-1}\in G_1$, $c_{i}\in G_2$, $c_{i+1}\in G_3$), or two different groups, one of which contains the first two of three consecutive vertices and the other group the third one (thus $c_{i-1},c_{i}\in G_1$, $c_{i+1}\in G_2$)
In this latter case, all we need is a permutation where $G_2$ is after $G_1$, then $c_i$ will be between its neighbors and thus the respective $\ell$ and $r$ vectors won't be negated when taking the sum over the edges of $C$. Similarly, in the first case, we need that $G_2$ is between $G_1$ and $G_3$.
Therefore, it is enough to show that for $m=\frac nk$ elements there are $O(\log m)$ permutations such that for any three elements $G_1,G_2,G_3$ there is a permutation in which $G_1<G_2<G_3$. A standard probabilistic argument shows that $O(\log m)$ random permutations work. In more detail, there are $m^3$ ordered triples, each permutation has probability $\frac 16$ to work for each triple, thus if we take $t$ independent permutations, the chance for any ordered tripe that none of the permutations work for it is $(1-\frac 16)^t$ and taking the union bound we need $m^3(1-\frac 16)^t<1$.
• I am not understanding this sentence well " Notice that this gives a nonzero sum for a cycle c1c2…ck if and only if the length of the cycle is even and every eventh vertex comes before (or after) every oddth vertex. Therefore, it has a good chance to work for long cycles" and this phrase well "two groups with an eventh element and a third group with an oddth element". What is eventh, oddth mean? – Brout Aug 6 '15 at 5:29
• In the first for $k=6$, I want that in the order $<$ given by the permutation satisfies $c_1,c_3,c_5<c_2,c_4,c_6$ or $c_1,c_3,c_5>c_2,c_4,c_6$. I hope from this you can also decipher what I meant in the second phrase... – domotorp Aug 6 '15 at 5:33
• "Our strategy will be to take t random permutations (with t⋅2n independent vectors) and take the sums on each edge to take care of all cycles longer than k." t random permutations of what? – Brout Aug 7 '15 at 17:34
• This is what I mean by alternating permutation en.wikipedia.org/wiki/Alternating_permutation (1<3>2<5>4<6>1). – Brout Aug 7 '15 at 17:45
• I have added it. – domotorp Aug 9 '15 at 18:50
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https://physics.stackexchange.com/questions/626939/why-is-there-no-blackbody-radiation-in-the-high-frequency-section-of-plancks-cu
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# Why is there no blackbody radiation in the high frequency section of Planck's curve?
Upon examining the curve describing blackbody thermal radiation, I noticed that the curves approaches (but never reaches) zero when increasing wavelength, but on the other hand it actually does reach zero at high frequency so I was wondering why?
• Good question. This confused many physicist for years and was at the birth of quantum mechanics. Apr 4 at 1:20
• What makes you think it reaches zero? Apr 4 at 4:14
• Let's state the behaviour carefully. Plotted against frequency, intensity scales as $\nu^3/(e^{\beta h\nu}-1)$, reaching $0$ at $\nu=0$ but not at any finite $\nu>0$. Plotted against wavelength, intensity scales as $\lambda^{-5}/(e^{\beta hc/\lambda}-1)$, which is asymptotic to $\lambda^{-5}e^{-\beta hc/\lambda}$ ($\lambda^{-4}/(\beta hc)$) for small (large) $\lambda>0$, so the $\lambda\to0^+,\,\lambda\to\infty$ one-sided limits are both $0$.
– J.G.
Apr 4 at 20:47
• There is a contradiction in the body of your question. May 11 at 11:05
In the frequency domain, the power spectral density has the form $$f^2$$ as the frequency approaches zero and the form $$f^3e^{-f}$$ as the freuency approaches infinity. In neither case does it reach zero at any finite frequency. You can argue about at which end it approaches zero more rapidly. Plotted on a log frequency axis, the high-frequency end of the spectrum would appear to approach zero very abruptly because of the exponential.
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http://mathematica.stackexchange.com/questions/15686/circular-angulargauge-does-not-roll-over-boundaries
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# Circular AngularGauge does not roll over boundaries
I am using the Mma9 AngularGauge function to develop a controll for a rotating stage. I am experiencing several problems:
1. I am unable to get the values {0°, 90°, 180°, 270°}.
2. I am unable to align those values at arbitrary locations, e.g. 0° at the top.
3. I cannot make the needle roll over the 0° / 360° boundary, i.e. to get from 10° to 350° I have to "roll back".
In particular the function ScaleDivisions drives me nuts. In the figure below the 0 in 360 is drawn twice, not clearly visible here but obvious on my screen. I am not concerned about the "°" right now and my Mma9 installed without any error messages (unitil now).
AngularGauge[Dynamic[x], {0, 360}, ScaleDivisions -> {20, 2}, ScaleOrigin -> {0, 2 \[Pi]}, ImageSize -> {256, 256}, GaugeLabels -> "Value", GaugeMarkers -> "InsideScale"]
-
I guess internally FindDivisions is being used which has the (documented) habit of yielding the number of divisions that it thinks looks best. This often approaches, but does not equal, the number the user specified. – Sjoerd C. de Vries Dec 4 '12 at 13:05
Is the 0 being drawn twice because it's showing both 0 and 360 in the same place? – cormullion Dec 4 '12 at 13:09
@cormullion yes, changing {0,360} into {0,359.9} does not draw 360 while still letting you select it (although x is not updated to be 360, it is only gets to 359.9 but shows as 360 in the gauge) – ssch Dec 4 '12 at 13:20
I guess that the developers' intent was that users would set the range to [0, 350} for gauges like this one. I suspect they did not intend to support roll over. I think they are mimicking physical gauges which don't roll over in my experience. – m_goldberg Dec 4 '12 at 14:18
The 'ClockGauge' appears to be a normal 'AngularGauge' but with different labels and roll over. If that is true, there must be some functionality to add the roll over. – Aart Goossens Dec 4 '12 at 15:08
For #2, you can adjust ScaleOrigin to set start/end angle to be wherever you like say you want 0 at angle $\theta$ use ScaleOrigin->{\[Theta]-2\[Pi],\[Theta]} or interchange the order to have the gauge increase in the other direction.
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https://www.godelia.org/2020/08/26/degeneration-in-quantum-mechanics/
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# Degeneration in quantum mechanics
Degeneration occurs when two or more independent wave functions have the same eigenvalue.
It is said that $$n$$ functions $$f_ {1}, f_ {2,} \ldots, f_ {n}$$ are linearly independent if the condition
$$\sum_{i}c_{i}f_{i}=0$$
it is satisfied when all the constants $$c_ {i}$$ are equal to zero.
The degree of degeneration of a system is the number of linearly independent functions with the same eigenvalue.
Theorem. Any linear combination of $$n$$ functions of a degenerate level of energy $$E$$ is also a eigenfunction of the Hamiltonian with energy $$E$$.
The proof is straightforward:
$$\hat{H}\psi_{1}=E\psi_{1},\hat{H}\psi_{2}=E\psi_{2},\ldots,\hat{H}\psi_{n}=E\psi_{n}$$
$$\varphi=\sum_{i}c_{i}\psi_{i}$$
$$\hat{H}\varphi=\hat{H}\sum_{i}c_{i}\psi_{i}=E\sum_{i}c_{i}\psi_{i}$$
$$\hat{H}\sum_{i}c_{i}\psi_{i}=\sum_{i}c_{i}\hat{H}\psi_{i}=\sum_{i}c_{i}E\psi_{i}=E\sum_{i}c_{i}\psi_{i}=E\varphi$$
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http://mathhelpforum.com/calculus/47894-finding-distance-given-velocity-cos.html
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# Math Help - Finding distance, given velocity with cos.
1. ## Finding distance, given velocity with cos.
What a wonderful website this is. Thank you all in advance for any help or guidance you can give me.
So, okay.
Find the distance traveled in 15 seconds by an object moving at a velocity of v(t) = 20 + 7 cos t feet per second.
Again, thank you for any help. I have no idea what to do with the cosine.
Edit: You know, I put this here because I was told it had to do with integrals? It might fit better in Trigonometry though. Sorry about that!
2. Originally Posted by AppleTini
What a wonderful website this is. Thank you all in advance for any help or guidance you can give me.
So, okay.
Find the distance traveled in 15 seconds by an object moving at a velocity of v(t) = 20 + 7 cos t feet per second.
Again, thank you for any help. I have no idea what to do with the cosine.
$s(t)=\int v(t)\,dt$
Therefore, $s(t)=\int (20+7\cos t)\,dt=20t+7\sin(t){\color{red}+C}$
Is there an initial condition for position?
--Chris
3. Originally Posted by Chris L T521
Is there an initial condition for position?
No, it doesn't seem so.
The problem is that I'm taking this AP Calculus class online [bad idea, for the record], and the online book really is not helpful at all. It hasn't actually talked about integrals or anything, and I certainly don't really remember them from two years ago. So I'm pretty much on my own. Thank you so much, though.
4. It MAY seem logical to assume one means the first 15 seconds.
The integral on [0,15] gives 300 + 7*sin(15) = 304.552
Unfortunately, it may NOT be a logical assumption. If we don't start watching for five seconds, the integral on [5,20] gives 300 + 7(sin(20)-sin(5)) = 313.103
We could play this game for a long time. One needs those initial conditions or some other guidance as to when or where we are clocking the 15 seconds.
In any case, you can estimate the answer well enough.
The constant "20" is, well, constant. It ALWAYS manages 300 in 15 seconds. The tricky part is the cosine, as you said. Interestingly, the cosine is periodic. Every $2\pi$ it has gotten you nowhere. In this way, we can eliminate some of the cosine problem. $15 = 2*(2\pi) + 0.387*(2\pi)$. This means you really have to worry only about the last 2.434 seconds of the trip, since the previous $4\pi$ seconds didn't get us anywhere! Of course, you still have to know where to start or stop. Just any 15 seconds will not due. We need to know which ones to watch.
5. Originally Posted by AppleTini
What a wonderful website this is. Thank you all in advance for any help or guidance you can give me.
So, okay.
Find the distance traveled in 15 seconds by an object moving at a velocity of v(t) = 20 + 7 cos t feet per second.
Again, thank you for any help. I have no idea what to do with the cosine.
Edit: You know, I put this here because I was told it had to do with integrals? It might fit better in Trigonometry though. Sorry about that!
Actually the distance s(t) is given by
$s(t) = \int |v(t)|~dt$
Fortunately in this case you get the same answer as has been given in the previous posts.
-Dan
6. displacement (a vector quantity) = $\int_{t_1}^{t_2} v(t) dt$
distance traveled (a scalar quantity) = $\int_{t_1}^{t_2} |v(t)| dt$
7. Well to find distance you have to integrate the whole v(t) funcn.
integrating dat you will get
s(t) = 20t + 7sint
put t=15
you will get
s= 140 + 7sin15
sin15 =.26 approx.
so you get the ans..
8. Originally Posted by vishalgarg
Well to find distance you have to integrate the whole v(t) funcn.
integrating dat you will get
s(t) = 20t + 7sint
put t=15
you will get
s= 140 + 7sin15
sin15 =.26 approx.
so you get the ans..
How does 20 times 15 equal 140?
-Dan
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http://mathhelpforum.com/trigonometry/12565-using-sin-cos-tan-formulas.html
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# Math Help - Using sin,cos,tan formulas.
1. ## Using sin,cos,tan formulas.
I have v = 1000sin@cos@tan(@/2)
and I need to rearrnge it to
v = asin^2(@) + bsin^4(@/2)
And hence find values a and b.
Tried using double angle formulas, but I'm having trouble. Thanks for the help!
2. Hello, classicstrings!
Is there a typo?
In the final form, aren't both angles ½θ ?
I have: .v .= .1000·sinθ·cosθ·tan(½θ)
and I need to rearrange it to: .v .= .a·sin²(½θ) + b·sin^4(½θ)
And hence find values a and b.
Identities
. - - . sinθ .= .2·sin(½θ)·cos(½θ)
. . . . cosθ .= .1 - 2·sin²(½θ)
. .tan(½θ) .= .sin(½θ)/cos(½θ)
We have: .v .= .1000 · sinθ · cosθ · tan(½θ)
. . . . . . . .v .= .1000 · 2·sin(½θ)·cos(½θ) · (1 - 2·sin²θ) · sin(½θ)/cos(½θ)
. . . . . . . .v .= .2000·sin²(½θ)·(1 - 2·sin²θ)
. . . . . . . .v .= .2000·sin²(½θ) - 4000·sin^4(½θ)
Therefore: .a = 2000, b = 4000
Edit: silly me . . . I had dropped a zero . . . sorry!
3. My error in forgetting the @/2.
Is there any chance that there is an error in your working?
I think you left out one zero in 1000, so a = 2000, and doesn't b = negative 4000? Thanks!
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https://gilkalai.wordpress.com/2012/07/23/a-weak-form-of-borsuk-conjecture/?like=1&source=post_flair&_wpnonce=8149a33672
|
## A Weak Form of Borsuk Conjecture
Problem: Let P be a polytope in $R^d$ with n facets. Is it always true that P can be covered by n sets of smaller diameter?
I also asked this question over mathoverflow, with some background and motivation.
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|
https://www.physicsforums.com/threads/is-it-distribution-function.97674/
|
# Homework Help: Is it distribution function ?
1. Oct 31, 2005
### Alexsandro
Could someone help me. I don't able to explain if is FG is a distribution fuction:
Show that if F and G are distribution functions and $0 \leq \lambda \leq 1$ then $\lambda.F + (1 - \lambda).G$ is a distribution function. Is the product F.G a distribution function?
Last edited: Oct 31, 2005
2. Oct 31, 2005
### mathman
In order see if a function is a distribution function, go back to the definition.
F(x) is a d.f. if F-> 1 as x -> inf, F-> 0 as x-> -inf. F(y)>=F(x) for y>x.
It should be easy for you to verify that in both examples you have a distribution function.
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http://www2.it.lut.fi/wiki/doku.php/common/latex_hints
|
## Documents
Good documents about LaTeX basics.
## Templates
A wide variety of templates are provided by itlab / MVPR:
## Required Packages
In Ubuntu, you need to install the minimum Latex environment (Master's Thesis template requirements):
apt-get install texlive-latex-base texlive-latex-extra gnuplot texlive-fonts-recommended
Or just install everything:
apt-get install texlive-full
## Tips
### Markerless Footnote
Adding footnote without a marker: http://help-csli.stanford.edu/tex/latex-footnotes.shtml
First define in the beginning of a document
\long\def\symbolfootnote[#1]#2{begingroup%
\def\thefootnote{\fnsymbol{footnote}}\footnote[#1]{#2}\endgroup}
To use the footnote:
\symbolfootnote[0]{footnote}
Other symbols can be used if 0 is replaced with 1…?
### Honouring Boundingbox in EPS
If you have an Encapsulated PostScript file gotten from somewhere, you might want to change the “viewport” or the area that is used in your document. You have to do two things:
• edit the code of the EPS file, change the %%BoundingBox values to your liking. You can check the right values with the cursor while viewing the image in gv. The format is: X-left Y-lower X-right Y-upper.
• In the LaTeX code, instead of includegraphics, use includegraphics* (note the star). You can also rotate the image with LaTeX.
### CVS keywords in text
There is a package called rcs, but you can also do without: http://www.tex.ac.uk/cgi-bin/texfaq2html?label=RCS Put this somewhere early in your .tex:
\def\RCS$#1: #2${\expandafter\def\csname RCS#1\endcsname{#2}}
Then you can use e.g.
\RCS$Date: 2007/01/29 16:30:15$
\date{\RCSDate{} UTC}
\maketitle
and the title will include the date of the last CVS commit. CVS will update the string between $'s automatically. ### Review comments in the text as footnotes \usepackage{color} \newcommand\newnotecommand[3]{% \newcommand#1[1]{{\color{#3}\footnote{{\color{#3}#2:} ##1}}}} \newnotecommand\pq{pq}{red} \newnotecommand\joni{Joni}{blue} The command \newnotecommand declares a note command by name, using arguments for nick and color. Usage in text: and is thus proved.\joni{viite?} This concludes ### Move figures and tables to the end of the document Some journals want all the figures and tables to be located at the end of the document. This can be accomplished by loading endfloat.sty: \usepackage{endfloat} Approximate locations of the figures without endfloat.sty are marked within the text in square brackets. ## Gnuplot Gnuplot is a nice program that can not only plot data but also fit functions etc. An example gnuplot script, that reads data from file paksuus.dat: #!/usr/bin/gnuplot set encoding iso_8859_1 set terminal postscript eps enhanced mono "Helvetica" 14 set out 'paksuus.eps' set size 0.9, 0.9 set title "Värähdysajan riippuvuus tangon halkaisijasta" set xlabel "d/mm" set ylabel "T/ms" set autoscale set xrange [[2:9]] set grid xtics ytics plot "paksuus.dat" using 1:(2*$2) notitle with points
and the data file could look like this:
8.0 59.2
6.0 79.5
5.0 89.8
4.0 115.9
3.0 151.3
You can also set terminal to latex so that gnuplot generates the figure as LaTeX code, but it will need configuring to get it to look nice. There is also pdf output format, but postscript output is more advanced and nicer to work with with black and white figures.
Here is a more complex example that fits a line to computed values and draws them:
#!/usr/bin/gnuplot
set encoding iso_8859_1
set out 'kerroin.eps'
set terminal postscript eps enhanced mono "Helvetica" 14
set size 0.9, 0.9
r = 7.9e3
E = 200e9
l = 0.800
f(d) = l*l * sqrt(r/E) / d
g(x) = a*x + b
fit g(x) "paksuus.dat" using (f($1/1000)*1000):(2*$2) via a, b
set xlabel "f(d)/ms"
set ylabel "T/ms"
set autoscale
- set xrange [[2:9]]
set grid xtics ytics
plot "paksuus.dat" using (f($1/1000)*1000):(2*$2) notitle with points,
g(x) notitle with line
Links to gnuplot resources:
## Using pixel images
Vector graphics is easy, no need think about resolution, if you can keep it in vector format. EPS is just fine for that. Sometimes you want to use pixel based images, like photographs, in a LaTeX document. To avoid creating huge files, and EPS format tends to be verbose, you have to think about image resolution.
You should estimate the physical size of the image in millimeters when it is printed on paper. Use it to compute the number of pixels by multiplying with pixels-per-millimeter resolution. Printer resolutions are usually in dots-per-inch, and the relationship between a dot and a pixel is not straightforward, so a little math is required.
There is a script that can automatically convert a pixel image to an EPS image and do the required scaling. The script can be found in the CVS, itlab/utils/pix2eps, or http://www.iki.fi/pq/htyot/textemplate/pix2eps . You can give the image maximum dimensions in millimeters or maximum width in percents of textwidth, assuming the standard M.Sc. thesis page format. Optionally the script converts the image to gray scale.
## Latex compilation using Makefile
There is a nicely working Makefile (zipped due to Wiki restrictions for the file extensions) written in the laboratory. Just add your document without extension to TARGET variable and say
make view
Alternative option is to use the ready packages provided for Ubuntu, for example latex-make or latex-mk. Include the rules into your Makefile and that's it, for example (Ubuntu 11.10 with latexlive and latex-mk):
NAME= report
TEXSRCS= report.tex
BIBTEXSRCS= report.bib
include LaTeX.mk
## Migration to ''texi2pdf''
Texi2pdf is similar to texi2dvi, but instead of DVI it produces directly PDF output. This avoids using PostScript as an intermediate format, allowing e.g. url{} commands to work better when the URL needs a line break.
Texi2pdf uses pdf(la)tex for processing LaTeX source. For graphics it means that JPG, PNG and PDF images are supported natively, but not EPS.
Migration considerations:
• For packages like graphicx and hyperref, replace dvips driver with pdftex.
• If you defined your own graphics extensions to eps, change them to png, jpg and pdf.
• Convert your eps images to pdf, or use original jpg or png images.
• When adding your images to CVS, do not forget -kb
• Check that all fonts are embedded in your document. Hints: http://axiom.anu.edu.au/~luke/embedded_fonts.html
Convert your eps images to pdf with epstopdf. Do check the result for correctness and font embedding. A command to insure embedding of all fonts:
epstopdf --nogs input.eps | gs -q -sDEVICE=pdfwrite -dAutoRotatePages=/None \
-dPDFSETTINGS=/printer -dCompatibilityLevel=1.4 -dMaxSubsetPct=100 \
-dSubsetFonts=true -dEmbedAllFonts=true -sOutputFile=output.pdf - -c quit
or as a Makefile rule:
%.pdf: %.eps
epstopdf --nogs $< | gs -q -sDEVICE=pdfwrite \ -dAutoRotatePages=/None -dPDFSETTINGS=/printer \ -dCompatibilityLevel=1.4 -dMaxSubsetPct=100 -dSubsetFonts=true \ -dEmbedAllFonts=true -sOutputFile=$@ - -c quit
Note that pixmaps will apparently be JPEG-compressed.
Also, do not use the following in your document or style files, because it breaks URL line breaking:
% Make URLs breakable, but also inactive.
\def\Url@Make@Link#1{\expandafter\href\expandafter{\Url@String}{#1}}
If you use both natbib and babel packages, load natbib before babel to prevent tilde showing up in citations. Loading natbib after babel and using citep-command will make “et al.” shown as “et~al.”.
## Bibtex entries
### Entry name
A good rule-of-thumb: Use up to the first three letters from surnames of the first three authors. First letter of each of them is capitalized. After the names add “:” and then the publication year. If there are multiple articles producing the same entry index, then use incremental number after the name part using two digits.
Examples:
1. Kamarainen, J.-K., Kyrki, V., Kalviainen, H., Doing things as a Scientific Manifest, In Proceedings of the 13th Weird Conference (Mexico City, Mexico, 2003), pp. 666-667.
2. Kamarainen, J.-K., Kyrki, V., Giving Up as an Important Scientific Contribution, In the Proceedings of the Annual Meeting of Idiots (Lappeenranta, Finland, 2003), pp. 1-2.
3. Kamarainen, J.-K., Kyrki, V., Kalviainen, H., How much we did without achieving anything, Journal of Complete Idiots 17, 2 (2003), pp. 100-101.
Result to the following bibtex entries:
@InProceedings{KamKyrKal:2003,
author = {J.-K. Kamarainen and V. Kyrki and H. Kalviainen},
title = {Doing things as Scientific Manifest},
OPTcrossref = {},
OPTkey = {},
booktitle = {Proceedings of the 13th Weird Conference},
pages = {666--667},
year = {2003},
}
@InProceedings{KamKyr:2003,
author = {J.-K. Kamarainen and V. Kyrki},
title = {Givin Up as Scientific Contribution},
OPTcrossref = {},
OPTkey = {},
booktitle = {Proceedings of the Annual Meeting of Idiots},
pages = {1--2},
year = {2003},
}
@Article{KamKyrKal02:2003,
author = {J.K. Kamarainen and V. Kyrki and H. Kalviainen},
title = {What have we done without achieving anything},
journal = {Journal of Complete Idiots},
year = {2003},
OPTkey = {},
volume = {17},
number = {2},
pages = {100--101},
}
It is convenient to save pdf files of these articles using the same convention, e.g., “KamKyrKal2003.pdf”.
### Entry types
Those standard ones - available in the emacs “entry type” menu Check Wikipedia and Google.
## Bibtex and personal list of publications
This can be conveniently done using the multibib latex package. For an example see the following (compile by typing “make view”):
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https://dsp.stackexchange.com/tags/signal-analysis/new
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You are really close! Change your signal and steering vectors to be complex. Specifically for the steering vectors, these coefficients are meant to act as phase shifts. Using a real sinusoid will introduce a phase shift term in the opposite angle direction, which you don't want. Doing this alone you will see an improvement in your pseudospectrum. In regards ...
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You're almost there; you just need to connect a few dots. Let your $\frac{10}{5 + i 2 \pi f} = G(f)$. Then $g(t) = 10 u(t) e^{-5 t}$. Now we get into that exponent part. Your $h(t) = g(t - t_0)$ is correct, but you're applying it incorrectly. You need to apply it to the part that I've labeled as $g(t)$: $h(t) = g(t - t_0) = 10 u(t - t_0) e^{-5 (t - t_0)}... 0 The principal idea behind my recommended approach is to identify characteristic points in your cycle. You can then make a mapping from time within the cycle (as it is occuring) and the location of that point within your representative cycle. Once you have a set of mapping points, create a best fit function. This will then give you a mapping function of ... 1 You may be able to use a modified transform to compute change in a time stretch parameter (I will use$\zeta$) versus time (t). Your success in being able to do this depends on the cross correlation properties of your pattern with time stretched versions of itself. Let me explain: First notice that the Fourier Transform is a correlation over all possible ... 0 Hello check this source To begin with, let’s remember what the fundamental frequency is and in what tasks it may be needed. The fundamental frequency, which is also referred to as F0, is the vibration frequency of the ligaments when pronouncing voiced sounds. When pronouncing unvoiced sounds, for example, by whispering or uttering hissing and ... 0 Wifi uses OFDM, which uses symbols that can transport many bytes at once. That means you can't have arbitrary long packets, but always need to use the next multiple of a symbol duration. 1 A more general expression states that for$ M \geq N$: $$\sum_{n= N}^{n = M} c = (M-N+1) \cdot c$$ where the derivation simply relies on fact that the epxression has (M-N+1) terms : $$\sum_{n= N}^{n = M} c = \{ c + c + ... + c\} = (M-N+1) \cdot c$$ And when applied for your particular case (with$N = -M$) it becomes:$$\sum_{n= -M}^{n = M} c = (M-(-... 0 For instance, from$-3$to$3$, you have$-3,\,-2\,-1,\,0\,1,\,2,\,3$, hence$2\times 3+1$terms. More generally, the sum from$-M$to$M$is composed of$2M+1$terms: indices with$m$strictly negative (a total of$M$), those which$m$strictly positive (a total of$M$), plus one at zero ($1$). If all terms are the same constant$c$, the total is$(2M+...
0
From what I can glance : The chattering seems to be high-frequency compared to your signal of interest, it should not be hard to filter this chattering noise. You simply need to identify the frequency band of your signal and the frequency band of this noise. Could your perform an FFT to analyze the frequencies of your noise? Then design a filter that will ...
0
Looking at documents like Lecture notes on Distributions, Hasse Carlsson, or Convolution dans l'espace $\mathcal{D}'_+(\mathbb{R})$, convolution of distributions can be defined under some technical conditions. However, when one of the operand has a compact support, as $\delta(t)$ does, the convolution is well-defined. From Wikipedia:Distribution-Convolution:...
2
Well, by definition of the $\delta$ distribution, you have: $\int_{-\infty}^{\infty} f(t) \delta(t-T)\, \textrm{d}t = f(T)$ The autocorrelation of a function $g(t)$ can be computed via: $\int_{-\infty}^{\infty} g^{*}(t)g(t + \tau)\, \textrm{d}t$, with $g^*$ as the complex conjugate of $g$. Since $\delta(t)$ is real-valued, this is conjugation can be ...
Top 50 recent answers are included
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http://math.stackexchange.com/questions/62298/what-can-the-writer-assume-in-a-proof
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# What can the writer assume in a proof?
When writing a proof, what level of mathematical understanding can I assume my reader has?
For example, can I assume they know all odd integers can be represented by $2q+1$? (Right?)
Or that all even integers can be represented by $2k$?
When do I have the power to draw on a theorem?
Can I always assume that my previous problem was right and cite it to help me with my current proof?
-
You can give the result before the new theorem. Then you either cite where you can find a proof or give a proof yourself. – Jonas Teuwen Sep 6 '11 at 13:55
And if the proof is not too long and not distracting, go with Jonas's second option. – J. M. Sep 6 '11 at 13:59
So I assume they know very little and try to help the reader as much as I can. and ensure that I don't get too off topic? – Dennis Hayden Sep 6 '11 at 14:01
I hope your readers don't "know all odd integers can be represented by 4q+1"... :) – t.b. Sep 6 '11 at 14:04
The question cannot be answered generally. You'll have to know which audience you're targeting, and there is no "standard audience". The assumptions can be very different according to whether you're writing an article for a professional journal, or helping a highschooler on math.SE (or something in between). – Henning Makholm Sep 6 '11 at 14:09
In mathematical writing, as in all writing, you need to think carefully about who your readers will be (and who you want them to be). It is rarely possible to write in a way which will be equally satisfactory to every conceivable person.
In this case, although you don't say so explicitly, it sounds like you are writing up problem sets for a course, so your intended reader is the grader of the problem set and/or the course instructor (perhaps the same person). With such a small audience it is feasible to simply ask them about their preferences, and while you probably don't want to do this before you turn in every single problem set, some questions in the beginning will probably make things go smoothly. In general though, this type of reader is someone who knows the material well -- probably better than you do -- and in most cases broadly knows what you are trying to say even before you say it. However, they are also looking for gaps and mistakes in your arguments. So in this case I would start by erring on the side of including more details / supporting reasoning, while understanding that if you do not express any given idea / argument in the best possible way you are more likely to be understood anyway than with a reader who really doesn't know what you're trying to tell her.
With regard to your specific questions:
can I assume they know all odd integers can be represented by $4q+1$[?]
Gosh, I hope not, since this is not true: e.g. $3 \neq 4q + 1$.
[Added: It seems that the "$4$" was just a typo which has since been corrected to $2$. In this case there may well be something to prove. It is relatively common to define an integer to be odd if it isn't even, and then one has to justify that an odd number is of the form $2k+1$. In fact, in an honors course for future math majors that I am currently teaching this came up in the first week. I defined an integer to be even if it is of the form $2k$ for some integer $k$ and odd if it is of the form $2k+1$, but there was still something to show: every integer is either even or odd and not both. The "not both" is easy, but the first part requires something: a few days later I proved it by mathematical induction, and then later stated it as a special case of the theorem about division with remainder. So no, for my intended audience I did not want to just assume that familiar facts about even and odd numbers are true, although I probably would do so in a course pitched either at a higher or a lower level.]
Or that all even integers can be represented by $2k$?
This is a standard definition of an even number (in fact, I can't think of any other standard definition at the moment). So this may well have come up before in class or in the course text. If not, and you are not working with any other definition of even, then you can just say something like "if $x$ is even -- that is, $x$ is of the form $2k$ for some integer $k$ -- ..." and move on.
Can I always assume that my previous problem was right and cite it to help me with my current proof?
I agree with all of Pete's advice. One additional point, if this is an intro number theory course that focuses on learning how to write proofs: Some people define odd numbers to be those numbers which are not of the form $2k$. In that case, it is not obvious that odd numbers are of the form $2 m+1$, and does require proof (in a more advanced course, this would count as standard knowledge). Other people define odd numbers to be numbers of the form $2m+1$, in that case it is not obvious that every number is either even or odd. (continued) – David Speyer Sep 6 '11 at 14:18
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https://mathmaine.com/2013/04/25/summary-logarithms/
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# Logarithms
Unlike the two most “friendly” arithmetic operations, addition and multiplication, exponentiation is not commutative. You will get a different result if you swap the value in the base with the one in the exponent (unless, of course, they are the same value):
$3^2 \ne 2^3$
The most significant impact of this lack of commutativity arises when you need to solve an equation that involves exponentiation: two different inverse functions are needed, one to undo the exponent (a root), and a different one to undo the base (a logarithm).
Just as there are many versions of the addition function (adding 2, adding 5, adding 7.23, etc.), and many versions of the “root” function (square roots, cube roots, etc.), there are also many versions of the “logarithm” function. Each version has a “base”, which corresponds to the base of its inverse exponential expression.
### Inverse Functions: Logarithms & Exponentials
Logarithms are labelled with a number that corresponds to the base of the exponential that they undo. For example, the symbols to the left of the equal sign below are read “log base b of b to the c”:
$log_b(b^c)=c$
“Log base b” is the inverse function of “b to the…”, so the two cancel each other out, leaving behind the argument of the inside function… “c” in this case. This same concept applies in more complex situations as well:
$log_4(4^{2x-5})=2x-5$
In each case, a function applied to its inverse leaves behind the argument (no matter how simple or complex it may be). It does not matter which inverse function is on the “outside”, if two inverse functions are “next” to each other with no other function or operation “in the way”, they cancel each other out. “Four to the…” is the inverse of “log base 4”, therefore:
$4^{log_4(3y+2)}=3y+2$
Note that if the bases are not the same in both the logarithm and the exponential, then they are not inverse functions… just as adding adding four is not the inverse of subtracting three.
Inverse functions only cancel one another out when they are applied directly to one another, with nothing else “in the way”: when the result of the inner function is not modified in any way before being used as an input to the outer function. Examples of where functions that are inverses of one another do not cancel each other out include:
$5^{(7+log_5(x))}\\*~\\*log_5(6\cdot 5^x)\\*~\\*log_5(2+5^x)$
All of the examples above do something to the result of the inner (inverse) function before evaluating the outer function. In the first example, 7 is added to the result of the logarithm. In the second, the power of 5 is multiplied by 6. In the third, the power of 5 has a 2 added to it. Therefore, none of the above examples can be simplified using inverse function principles.
However, the Laws of Exponents or Logarithms will allow us to simplify the first two examples a bit, as you will see below. The last example above cannot be further simplified.
### Logarithms Produce Exponents
The result of a logarithm is always an exponent… an exponent of the logarithm’s base. So, logarithms answer questions such as “what exponent of 2 produces a result of 16?”:
$log_{2}(16)=4$
Evaluating a logarithm always produces a power of the logarithm’s base.
The two equivalent equations below are often referred to as the definition of a logarithm. The first equation shows that “c” is the result of a logarithm, therefore if used as a power of the logarithm’s base “b“, you will get back to “a“… which was your starting point:
$log_b(a)=c~~~ means~that\\*~\\*a=b^c$
Alternatively, you can take “log base b” of both sides of the second equation, simplify the right side by canceling out inverse functions, and you will end up with the first equation:
$a=b^c\\*~\\*log_b(a)=log_b(b^c)\\*~\\*log_b(a)=c$
### Common and Natural Logarithms
Two bases, 10 and e, are used so frequently with logarithms that they have their own notation:
$log(a)=log_{10}(a)~~~Common~Logarithm\\*~\\*ln(a)=log_e(a)~~~~~Natural~Logarithm$
Since our number system uses ten digits, and each digit in a multi-digit number represents a different power of 10, for example:
$123 = 1\cdot 10^2+2\cdot 10^1+3\cdot 10^0$
it makes sense that we would be interested in powers of 10 more so than other bases. This greater interest has led to a slightly shorter notation for what are called “Common Logarithms”, or “log base 10”, as shown above. If no base is indicated for a logarithm, it is assumed to be base 10, or a Common Logarithm.
Another common base for logarithms is “e“, a number you may not have encountered before. “e” is an irrational number (its decimal representation never terminates or repeats), which explains why it, like “pi”, is usually referred to by name. “e” arises when modeling situations where growth occurs continuously, for example when an initial population of 100 grows continuously at 2%:
$y=100\cdot e^{0.02t}$
If you need to solve such an equation for “t”, the easiest way to do so is by using the inverse function of “e to the…” , which is log base e. This function is referred to as a “Natural Logarithm”, or when using function notation by writing “ln”:
$\frac{y}{100}=e^{0.02t}\\*~\\*ln\left(\frac{y}{100}\right)=ln(e^{0.02t})\\*~\\*ln\left(\frac{y}{100}\right)=0.02t\\*~\\*ln\left(\frac{y}{100}\right)\div 0.02=t$
Without logarithms, we could not get the “t” out of the exponent in the example above to solve for it.
### Laws of Logarithms
Since the result of a logarithm is an exponent, it should come as no surprise that three of the Laws of Logarithms mirror the Laws of Exponents. To derive them, let us work with two real numbers expressed as a power of a base. Any base will do, but since we work with numbers that are powers of 10 the most in our daily lives, base 10 has been used below. This also allows us to use Common Logarithms in the derivation, so that we don’t need to indicate a “base 10” below each logarithm.
Any real number can be represented as a power of ten. For example:
$3=10^{0.4771213...}\\*~\\*12=10^{1.0791812...}$
Let’s use this idea to express a number “A” as a power of ten, as shown in equation (1) below. Take Log base 10 of both sides of this equation, simplify, and the resulting equation (2) is mathematically equivalent to equation (1), but has been solved for “a“, the power of ten:
$(1)~~~~A=10^a\\*~\\*~~~~~~~~~log(A)=log(10^a)\\*~\\*(2)~~~~log(A)=a$
Since two quantities are needed to explain the Laws of Logarithms, we’ll define a second value in the same way:
$(3)~~~~B=10^b\\*~\\*~~~~~~~~~log(B)=log(10^b)\\*~\\*(4)~~~~log(B)=b$
These two definitions can now be used to derive the following “laws”:
1) The logarithm of a product equals the sum of the logarithms of the factors:
$log(A\cdot B)\\*~\\*=log(10^a \cdot 10^b)~~~~~~~~~Substituting~(1)~and~(3)~from~above\\*~\\*=log(10^{a+b})~~~~~~~~~~~~~Laws~of~exponents\\*~\\*=a+b~~~~~~~~~~~~~~~~~~~~Inverse~functions~cancel\\*~\\*=log(A)+log(B)~~~~~Substituting~(2)~and~(4)~from~above\\*~\\*\therefore \mathbf{log(A\cdot B)=log(A)+log(B)}$
As you will hopefully recall from the Laws of Exponents, when like bases are being multiplied we add the exponents. This is exactly the process that this property of logarithms describes. The first line requires us to calculate the Common Logarithm, or power of ten, of the product AB. We know by the laws of exponents that this exponent must be the sum of a (A’s power of ten) and b (B’s power of ten), which is the same thing as the sum of log(A) and log(B).
Note that this identity is used just as often from left-to-right as it is from right-to-left. You are welcome to convert a sum of logarithms (with the same base) into the logarithm of a product, or the logarithm of a product into a sum of logarithms. So, don’t think of this identity as a one-way-street… it is frequently used in either direction.
2) The logarithm of a quotient equals the logarithm of the numerator less the logarithm of the denominator:
$log\left(\dfrac{A}{B}\right)\\*~\\*=log\left(\dfrac{10^a}{10^b}\right)~~~~~~~~~~~~Substituting~(1)~and~(3)\\*~\\*=log(10^{a-b})~~~~~~~~~~~~~Laws~of~exponents\\*~\\*=a-b~~~~~~~~~~~~~~~~~~~~Inverse~functions~cancel\\*~\\*=log(A)-log(B)~~~~~Substituting~(2)~and~(4)\\*~\\*\therefore \mathbf{log\left(\dfrac{A}{B}\right)=log(A)-log(B)}$
Once again, from the Laws of Exponents, when like bases are divided we subtract the exponents. This identity mirrors that law of exponents in the same way as the previous one, and is also used in either direction… so keep an eye out for expressions that look like either side of the last line above. Sometimes you will prefer to have things expressed as the logarithm of a quotient, and other times you will prefer to express things as a difference of logarithms.
3) The logarithm of an exponential equals the exponent times the logarithm of the base:
$log(B^c)\\*~\\*=log([10^b]^c)~~~~Substituting~(3)\\*~\\*=log(10^{bc})~~~~~~Laws~of~exponents\\*~\\*=bc~~~~~~~~~~~~~~~Inverse~functions~cancel\\*~\\*=log(B)\cdot c~~~~~Substituting~(4)\\*~\\*=c\cdot log(B)\\*~\\*\therefore \mathbf{log(B^c)=c\cdot log(B)}$
This is very handy for both a) getting a coefficient that is in front of a logarithm “out of the way” so that an inverse function may be used, or b) getting the expression in an exponent out of the exponent, and down where we can work with it more easily. Once again, this identity is often used in either direction.
4) And lastly, the base change formula. This formula allows the value of a logarithm with any base to be calculated using logarithms with a different base. The formula is usually used to convert logarithms into base 10 or base e, both of which are found on many calculators (as well as in tables of logarithms at the back of textbooks).
$(5)~~~b^c=a\\*~\\*~~~~~~~~log_b(b^c)=log_b(a)~~~~~~~Taking~the~log_b~of~both~sides~of~(5)\\*~\\*(6)~~~c=log_b(a)~~~~~~~~~~~~~~Inverse~functions~cancel~each~other\\*~\\*The~above~is~one~way~to~solve~for~c.~Here~is~another\\*~\\*~~~~~~~~log_x(b^c)=log_x(a)~~~~~~Taking~the~log_x~of~both~sides~of~(5)\\*~\\*~~~~~~~~c\cdot log_x(b)=log_x(a)~~~~~~~Log~of~an~exponential~rule~(3)~above\\*~\\*(7)~~~c=\dfrac{log_x(a)}{log_x(b)}\\*~\\*~~~~~~\therefore \mathbf{log_b(a)=\dfrac{log_x(a)}{log_x(b)}}~~~~~Substituting~(6)~into~(7)$
The result on the last line above is called the base change formula, as it allows a logarithm base “b” to be converted into a ratio of logarithms in any base you choose… labelled “x” above. Note that this derivation uses Law #3 from above.
### Using the Laws of Logarithms
Returning to a couple of examples shown above, let’s use the Laws of Logarithms to change the way they look a bit. The first example was:
$5^{(7+log_5(x))}\\*~\\*=5^7 \cdot 5^{log_5(x)}~~~Laws~of~exponents\\*~\\*=5^7 \cdot x~~~~~~~~~Inverse~functions~cancel$
And the second example was:
$log_5(6\cdot 5^x)\\*~\\*=log_5(6)+log_5(5^x)~~~Laws~of~Logarithms\\*~\\*=log_5(6)+x~~~~~~~~~~~Inverse~functions~cancel\\*~\\*=\dfrac{log(6)}{log(5)}+x~~~~~~~~~~~Base~change~formula$
Be careful! The following do not follow a pattern found in any of the first three laws of logarithms, therefore they cannot be manipulated in any way using those laws. The only actions you could take on them would be to evaluate them (if you know the value of “a” and “b”), or use the base change formula to rewrite in terms of logarithms with a different base:
$log(a+b)\\*~\\*log(a-b)$
### Why Logarithms?
Logarithms have many uses, some of which appear in the media regularly, and some of which are more special-purpose. In addition to their usefulness in mathematics (as the inverse function of an exponential, which allows us to solve for a variable in the exponent), logarithms are often used to make it easier to think about and compare values in situations that involve numbers that span a very large range. By talking about values as exponents of a base, usually base 10, it is easier to work with both tiny numbers and huge ones. For example, consider the following four values. Their decimal representations require a range of five places to the right of the decimal to 10 places to the left of the decimal:
$log(0.0001)=~~~~~~~-4\\*~\\*log(10)=~~~~~~~~~~~~~~~~1\\*~\\*log(10,000)=~~~~~~~~~~4\\*~\\*log(1,000,000,000)=9$
yet by taking the logarithm of each value, and referring to each value by its power of ten, we can use a much smaller number of digits (one in this example), with a much smaller range (negative four to nine in this case), which can make working with quantities that span such a large range much simpler.
Graphing data with a large range
Logarithms are often used when graphing data about something that is growing. By either graphing the logarithm of the data on the vertical axis, or graphing the raw data on “semi-log” graph paper (which has a linearly scaled horizontal axis, and a logarithmic vertical axis), you can easily tell if the data reflects a constant growth rate or not.
A constant growth rate produces a curve that rises faster and faster as you move to the right when graphed on “normal” graph paper, but will produce a graph with a constant slope when plotted using semi-log graph paper. This is very useful when looking at multiple years of sales or earnings data from growing companies, as you can instantly see if the company’s growth is accelerating (the slope of the graph becomes greater), remaining constant (the slope is constant), or slowing (the slope of the graph becomes smaller).
A good example of using a graph on semi-log paper to analyze changes in growth rates can be found in this 2009 swine flu graph from Wikipedia:
The “Total” (blue points above the other curves) shows a very fast and relatively constant initial growth rate through early to mid-May (we can infer this from the fact that the graph is almost linear during this period), followed by a transition to a slower but also relatively constant long term growth rate through the end of June. Notice that each value along the vertical axis is double the previous one, even though the axis tick marks are all the same distance apart. This is a semi-log (base 2) graph, because the distances from the origin on the vertical axis are proportional to the “Log base 2” of the number of cases.
Other quantities in our world and universe for which this approach is useful include:
The Richter scale
The Richter scale is used to measure earthquake strengths. Seismographs measure the amplitude (size or strength) of waves that travel through the earth from the site of an earthquake to the measuring station. The Richter scale is based on the logarithm of the measured wave amplitude, so a Richter Scale measurement is a power of 10. An earthquake of magnitude 3 is ten times more powerful than one of magnitude 2 (a micro-earthquake that is not able to be felt).
The chart below shows the magnitude reported by the U.S. Geological Survey for the more significant earthquakes around the earth over a 24 hour period. The most intense earthquake on that day measured a 6.6 on the Richter scale, while the least intense one measured 2.5. Since these numbers are the result of logarithms, they are exponents – so their difference (4.1) tells us the exponent of the ratio of the original values. The strongest earthquake that day was $10^{4.1}=12,589$ times more powerful than the weakest one.
Decibels
The strength of a signal or sound is usually measured in decibels, which is calculated by dividing the signal’s strength by a standard reference level, taking the logarithm of the result, then multiplying that by 10. Therefore, a decibel measurement is ten times an exponent of ten. To interpret the meaning of a 20 dB measurement, divide it by ten and use that result as a power of ten
$10^{20/10}=10^2=100$
which tells you that the measured signal is one hundred times stronger than a 0 dB signal. A 30 dB signal is
$10^{30/10}=10^3=1,000$
one thousand times stronger than a 0 dB signal.
pH
The quantity of hydrogen ion activity determines how a solution reacts with many elements. A solution with a large quantity of active hydrogen ions is called “acidic”, and a solution with relatively few active hydrogen ions is called “basic”. pH is a measure of how acidic or basic a solution is, and is calculated by taking the logarithm of the reciprocal of the hydrogen ion activity in a solution. Therefore, a higher level of hydrogen ion activity will result in a a lower pH value. A pH value of 7 is considered neutral (neither acidic nor basic), so a solution with a pH of 5 would have
$10^{7-5}=10^2=100$
one hundred times as many active hydrogen ions as a neutral solution. A solution with a pH of 10 would have
$10^{7-10}=10^{-3}=\dfrac{1}{1,000}$
one thousandth as many active hydrogen ions as a neutral solution.
Pitch
The higher pitched of two musical notes that we perceive to be an octave apart has a frequency that is double that of the lower pitch. Therefore the formula for converting a sound frequency to a pitch uses $log_2$ to convert a frequency into a “number of doublings”. The number of doublings (relative to a standard pitch) tells us how many octaves (and fractions of an octave) apart the sounds are. Comparing the pitch of a 3,520 Hz tone with a 440 Hz tone, we can determine that they are
$log_2(3,520/440)\\*~\\*=log_2(8)\\*~\\*=log_2(2^3)\\*~\\*=3$
exactly three octaves apart.
Multiplication, Division, and Powers
If you do not have a calculator handy, but do have a table of logarithms handy (something that used to be true more often than it is today), you can use the table to speed up the process of manually calculating products, quotients, or powers. By converting the relevant numbers into powers of ten, you can then use the laws of exponents to add, subtract, or multiply the exponents to arrive at the exponent of the answer:
$(123,000)( 917,000)\\*~\\*=(1.23)(10^5)(9.17)(10^5)\\*~\\*=(1.23)(9.17)(10^{10})~~~~~~~~Laws~of~Exponents\\*~\\*=10^{log(1.23 \cdot 9.17)} \cdot 10^{10}~~~~~~~~Inverse~functions\\*~\\*=10^{log(1.23)+log(9.17)} \cdot 10^{10}~~~Laws~of~Logarithms\\*~\\*=10^{0.0899051+0.9623693} \cdot 10^{10}\\*~\\*=10^{1.0522744} \cdot 10^{10}$
The last step is to look up exponent of ten in the body of the table of logarithms to convert it back into the answer to the original problem. Since the two numbers I started with had three significant digits each, I rounded the answer to 6 significant digits:
$10^{1.0522744} \cdot 10^{10}\\*~\\*=10^{0.0522744} \cdot 10^{11}\\*~\\*=1.12791\cdot 10^{11}\\*~\\*=112,791,000,000$
A similar process, which also relies on the laws of exponents, can be used to raise a number to a power:
$3.1416^6\\*~\\*=10^{log(3.1416^6)}\\*~\\*=10^{6 \cdot log(3.1416)}~~~Laws~of~Logarithms\\*~\\*=10^{6 \cdot 0.49715}~~~~~~Using~table~of~logarithms\\*~\\*=10^{2.9829}\\*~\\*=10^2 \cdot 10^{0.9829}\\*~\\*=100 \cdot 9.6139~~~Using~table~of~logarithms~in~reverse\\*~\\*=961.39$
While the examples above may seem lengthy, with a little practice the process becomes a faster process than doing the calculation by hand. However… today’s calculators and computers are faster yet.
### Summary
The result of a logarithm is an exponent… an exponent of the logarithm’s base.
Logarithms make it easier to read comparable percentage changes for both very large and very small numbers on the same graph by converting them to powers of a common base.
Logarithms allow us to isolate a variable that is in the exponent of an exponential expression. Roots allow us to solve for a variable that is in the base of an exponential expression.
The laws of logarithms, like the laws of exponents, provide us with ways to manipulate the appearance of certain expressions or equations without affecting the quantities or relationships that they represent. They are another useful tool in our Algebraic toolbox, particularly when working with exponential expressions or equations.
For a slightly different approach to introducing logarithms, with additional useful or interesting information, check out “It’s the law too – the Laws of Logarithms“.
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https://ask.sagemath.org/questions/41219/revisions/
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# Revision history [back]
### Calculations in quotient of a free algebra
I want to define Sweedler's four-dimensional Hopf algebra, which is freely generated by $x,y$ and subject to the relations \begin{align} x^2 = 1, \qquad y^2 = 0, \qquad x\cdot y = - y\cdot x~ , \end{align} but I don't see how to do it.
I have tried the following:
sage: A.<x,y> = FreeAlgebra(QQbar)
sage: I = A*[x*x - 1, y*y, x*y + y*x]*A
sage: H.<x,y> = A.quo(I)
sage: H
Quotient of Free Algebra on 2 generators (x, y) over Algebraic Field by the ideal (-1 + x^2, y^2, x*y + y*x)
But then I get
sage: H.one() == H(x*x)
False
So is this currently possibly using a different method?
Thanks
### Calculations in quotient of a free algebra
I want to define Sweedler's four-dimensional Hopf algebra, which is freely generated by $x,y$ and subject to the relations \begin{align} x^2 = 1, \qquad y^2 = 0, \qquad x\cdot y = - y\cdot x~ , \end{align} but I don't see how to do it.
I have tried the following:
sage: A.<x,y> = FreeAlgebra(QQbar)
sage: I = A*[x*x - 1, y*y, x*y + y*x]*A
sage: H.<x,y> = A.quo(I)
sage: H
Quotient of Free Algebra on 2 generators (x, y) over Algebraic Field by the ideal (-1 + x^2, y^2, x*y + y*x)
But then I get
sage: H.one() == H(x*x)
False
So is this currently possibly using a different method?
Thanks
### Calculations in quotient of a free algebra
I want to define (the algebra part of) Sweedler's four-dimensional Hopf algebra, which is freely generated by $x,y$ and subject to the relations $$x^2 = 1, \qquad y^2 = 0, \qquad x\cdot y = - y\cdot x~ ,$$ but I don't see how to do it.
I have tried the following:
sage: A.<x,y> = FreeAlgebra(QQbar)
sage: I = A*[x*x - 1, y*y, x*y + y*x]*A
sage: H.<x,y> = A.quo(I)
sage: H
Quotient of Free Algebra on 2 generators (x, y) over Algebraic Field by the ideal (-1 + x^2, y^2, x*y + y*x)
But then I get
sage: H.one() == H(x*x)
False
So is this currently possibly using a different method?
Thanks
4 retagged tmonteil 22063 ●25 ●157 ●407 http://wiki.sagemath.o...
### Calculations in quotient of a free algebra
I want to define (the algebra part of) Sweedler's four-dimensional Hopf algebra, which is freely generated by $x,y$ and subject to the relations $$x^2 = 1, \qquad y^2 = 0, \qquad x\cdot y = - y\cdot x~ ,$$ but I don't see how to do it.
I have tried the following:
sage: A.<x,y> = FreeAlgebra(QQbar)
sage: I = A*[x*x - 1, y*y, x*y + y*x]*A
sage: H.<x,y> = A.quo(I)
sage: H
Quotient of Free Algebra on 2 generators (x, y) over Algebraic Field by the ideal (-1 + x^2, y^2, x*y + y*x)
But then I get
sage: H.one() == H(x*x)
False
So is this currently possibly using a different method?
Thanks
|
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http://stackoverflow.com/questions/1395105/getting-latex-into-r-plots
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# Getting LaTeX into R Plots
I would like to add LaTeX typesetting to elements of plots in R (e.g: the title, axis labels, annotations, etc.) using either the combination of base/lattice or with ggplot2.
Questions:
• Is there a way to get LaTeX into plots using these packages, and if so, how is it done?
• If not, are there additional packages needed to accomplish this.
For example, in Python matplotlib compiles LaTeX via the text.usetex packages as discussed here: http://www.scipy.org/Cookbook/Matplotlib/UsingTex
Is there a similar process by which such plots can be generated in R?
-
Here's an example using ggplot2:
q <- qplot(cty, hwy, data = mpg, colour = displ)
q + xlab(expression(beta +frac(miles, gallon)))
-
Unfortunately, this doesn't have nearly the features of LaTeX. – Myles Baker Sep 11 '14 at 6:32
As stolen from here, the following command correctly uses LaTeX to draw the title:
plot(1, main=expression(beta[1]))
See ?plotmath for more details.
-
Interesting, also good stuff with demo(plotmath) So mathematical notation has to be re-interpreted through plotmath's syntax? That seems like a glorious waste of time, especially if you have an involved LaTeX expression. That's why I like matplotlib's ability to compile LaTeX itself. Is there something that can take LaTeX and generate plotmath syntax? – DrewConway Sep 8 '09 at 19:20
Not that I know of. There's an interesting post at RWiki about getting latex to work with ggplot2: wiki.r-project.org/rwiki/… – Christopher DuBois Sep 8 '09 at 20:06
You can generate tikz code from R: http://r-forge.r-project.org/projects/tikzdevice/
-
This package is now on CRAN. cran.r-project.org/web/packages/tikzDevice – Rob Hyndman Sep 13 '09 at 4:28
I just find that the package was removed from CRAN. – Xin Guo Nov 5 '13 at 19:02
It appears that the package is still available at r-forge. Additionally it is available here: github.com/Sharpie/RTikZDevice – Mica Dec 13 '13 at 17:00
This script contains a function latex2exp to approximately translate LaTeX formulas to R's plotmath expressions. You can use it anywhere you could enter mathematical annotations, such as axis labels, legend labels, and general text.
For example:
x <- seq(0, 4, length.out=100)
alpha <- 1:5
plot(x, xlim=c(0, 4), ylim=c(0, 10), xlab='x', ylab=latex2exp('\\alpha
x^\\alpha\\text{, where }\\alpha \\in \\text{1:5}'), type='n')
for (a in alpha)
lines(x, a*x^a, col=a)
legend('topleft', legend=latex2exp(sprintf("\\alpha = %d", alpha)), lwd=1, col=alpha)
produces this plot.
-
bloody awesome.... cheers... – Nicholas Hamilton Jul 27 '15 at 13:53
Here's a cool function that lets you use the plotmath functionality, but with the expressions stored as objects of the character mode. This lets you manipulate them programmatically using paste or regular expression functions. I don't use ggplot, but it should work there as well:
express <- function(char.expressions){
return(parse(text=paste(char.expressions,collapse=";")))
}
par(mar=c(6,6,1,1))
plot(0,0,xlim=sym(),ylim=sym(),xaxt="n",yaxt="n",mgp=c(4,0.2,0),
xlab="axis(1,(-9:9)/10,tick.labels,las=2,cex.axis=0.8)",
ylab="axis(2,(-9:9)/10,express(tick.labels),las=1,cex.axis=0.8)")
tick.labels <- paste("x >=",(-9:9)/10)
# this is what you get if you just use tick.labels the regular way:
axis(1,(-9:9)/10,tick.labels,las=2,cex.axis=0.8)
# but if you express() them... voila!
axis(2,(-9:9)/10,express(tick.labels),las=1,cex.axis=0.8)
-
I did this a few years ago by outputting to a .fig format instead of directly to a .pdf; you write the titles including the latex code and use fig2ps or fig2pdf to create the final graphic file. The setup I had to do this broke with R 2.5; if I had to do it again I'd look into tikz instead, but am including this here anyway as another potential option.
My notes on how I did it using Sweave are here: http://www.stat.umn.edu/~arendahl/computing
-
Here's something from my own Lab Reports.
• tickzDevice exports tikz images for LaTeX
• Note, that in certain cases "\\" becomes "\" and "$" becomes "$\" as in the following R code: "$z\\frac{a}{b}$" -> "$\z\frac{a}{b}$\"
• Also xtable exports tables to latex code
The code:
library(reshape2)
library(plyr)
library(ggplot2)
library(systemfit)
library(xtable)
require(graphics)
require(tikzDevice)
setwd("~/DataFolder/")
AR <- subset(Lab5p9,Region == "Forward.Active")
# make sure the data names aren't already in latex format, it interferes with the ggplot ~ # tikzDecice combo
colnames(AR) <- c("$V_{BB}[V]$", "$V_{RB}[V]$" , "$V_{RC}[V]$" , "$I_B[\\mu A]$" , "IC" , "$V_{BE}[V]$" , "$V_{CE}[V]$" , "beta" , "$I_E[mA]$")
# make sure the working directory is where you want your tikz file to go
setwd("~/TexImageFolder/")
# export plot as a .tex file in the tikz format
tikz('betaplot.tex', width = 6,height = 3.5,pointsize = 12) #define plot name size and font size
#define plot margin widths
par(mar=c(3,5,3,5)) # The syntax is mar=c(bottom, left, top, right).
ggplot(AR, aes(x=IC, y=beta)) + # define data set
geom_point(colour="#000000",size=1.5) + # use points
geom_smooth(method=loess,span=2) + # use smooth
theme_bw() + # no grey background
xlab("$I_C[mA]$") + # x axis label in latex format
ylab ("$\\beta$") + # y axis label in latex format
theme(axis.title.y=element_text(angle=0)) + # rotate y axis label
theme(axis.title.x=element_text(vjust=-0.5)) + # adjust x axis label down
theme(axis.title.y=element_text(hjust=-0.5)) + # adjust y axis lable left
theme(panel.grid.major=element_line(colour="grey80", size=0.5)) +# major grid color
theme(panel.grid.minor=element_line(colour="grey95", size=0.4)) +# minor grid color
scale_x_continuous(minor_breaks=seq(0,9.5,by=0.5)) +# adjust x minor grid spacing
scale_y_continuous(minor_breaks=seq(170,185,by=0.5)) + # adjust y minor grid spacing
theme(panel.border=element_rect(colour="black",size=.75))# border color and size
dev.off() # export file and exit tikzDevice function
-
I just have a workaround. One may first generate an eps file, then convert it back to pgf using the tool eps2pgf. See http://www.texample.net/tikz/examples/eps2pgf/
-
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https://www.physicsforums.com/threads/taylor-series.419669/
|
# Taylor Series
• Start date
• #1
76
0
## Homework Statement
Let $$f(z)=\sum_{n=0}^{\infty} a_n z^n$$ be analytic at {z: |z|<R} and satisfies:
$$|f(z)| \leq M$$ for every |z|<R.
Let's define: d=the distance between the origin and the closest zero of f(z).
Prove: $$d \geq \frac{R|a_0|}{M+|a_0|}$$.
Hope you'll be able to help me
Thanks !
## The Attempt at a Solution
I've tried using Cauchy's Inequality... But it doesn't give anything new for $$a_0$$.
I've also tried isolating $$a_0$$ from this inequality, but it gives me nothing...
Hope someone will be able to help me
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https://brilliant.org/problems/a-good-name-for-this-would-be-appreciated/
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# A good name for this would be appreciated
A particle moved in a straight line so that position $x$ cm relative to $O$ at time $t$ seconds is given by $x = t^3 - 6t^2 +5, t \geq 0$. Find the sum of the magnitudes of its initial position, speed and acceleration. If velocity or acceleration point in the minus $x$ direction, add that magnitude as a negative value to the sum.
×
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http://clay6.com/qa/1638/each-of-the-following-defines-a-relation-on-n-begin-i-quad-x-is-greater-tha
|
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# Each of the following defines a relation on N : \begin{array}{1 1} (i)\quad x\; is\; greater\; than\; y,x,y\quad N\\(ii)\quad x+y=10,x,y\quad N\\(iii)\quad x\;y\;is\;square\; of\; an\; integer\;x,y\quad N\\(iv)\quad x+4y=10\;x,y\quad N\end{array}Determine which of the above relations are reflexive,symmetric and transitive.
Can you answer this question?
## 1 Answer
0 votes
Toolbox:
• A relation R in a set A is called $\mathbf{ reflexive},$ if $(a,a) \in R\;$ for every $\; a\in\;A$
• A relation R in a set A is called $\mathbf{symmetric}$, if $(a_1,a_2) \in R\;\Rightarrow\; (a_2,a_1)\in R \; for \;a_1,a_2 \in A$
• A relation R in a set A is called $\mathbf{transitive},$ if $(a_1,a_2) \in R$ and $(a_2,a_3) \in R \; \Rightarrow \;(a_1,a_3)\in R$ for all$\; a_1,a_2,a_3 \in A$
Given R defined by
$R \{(x,y):x \;is\; greater\; than\; y\; \qquad x,y \in N\}$
Consider (1,1) one cannot be greater than for every element $x \in N$
$x > x$
Hence R is not reflexive
Consider $(3,2) \in R$ ie 3 is greater than 2
but $(2,3) \notin$ as 2 is not greater than 3
R is not symmetric
Consider $(3,2),(2,1) \in R$
ie $3 > 2 \;and \;2 > 1$
$=>3 > 1$
Hence $(3,1) \in R$
R is transitive
Solution:R is transitive but not reflexive and not symmetric
answered Mar 4, 2013 by
edited Mar 27, 2013 by meena.p
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https://aliquote.org/post/vim-shortcuts/
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# aliquote
## < a quantity that can be divided into another a whole number of time />
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Here is a list of the personal shortcuts I use the most in Vim. Nothing special, but feel free to copy/paste in case you find anything useful for your own workflow. Of note, I’ve read so much posts on remapping everything to Vim’s hjkl hot keys that I got tired of it, really. I use the hjkl keys when I think I’ll need to repeat a command, otherwise we just have plain old arrow keys, right? Likewise, in Tmux, the arrow keys allow to switch to any pane easily. Arrow keys are mapped in many applications as well, whether it be Firefox, iTerm, Gnome terminal, Kitty, etc. Even in Vim you can use arrow keys with to navigate along the way. Home row, you said? Come on, the arrows are just below, on your right – not so far away in fact. But let’s go to the point.
Of course, I realize this is all subjective and it really depends on your needs and what you expect from your text editor. I for one consider my text editor as a helping hand: When I need to perform an action, give me the means to do it quickly or efficiently; I have poor abstract memory but if I repeat the same action a sufficient amount of time it will become muscle memory; I want it to correct my misspellings and fix my code formatting automagically, and sometimes – sometimes only – suggest better alternatives to what I wrote (mostly code, not prose). Above all, my text editor must be as fast lightning. I don’t need sugar candy app, or fancy editors that look like Christmas trees with everything highlighted here and there. I don’t really care about the color theme as long as it’s not everywhere unnecessarily. My current color scheme in Vim is deliberately refined to just highlight intentional comments (which must be emphasized), keywords and constants – and that’s all good. I talked about those choices earlier on.
Alabaster highlights comments. Most themes try to dim comments by using low-contrast greys. I think if code was complex enough that it deserved an explanation then it’s that explanation we should see and read first. It would be a crime to hide it. — Nikita Prokopov (tonsky)
Snippets were fun a while ago, but I don’t like them anymore. Most of the snippet-based packages are probably inspired by the great Textmate app, which I used to use a while back. I’m not a robot, I can write, slowly but I like it nevertheless – I mean, to write, not slowly. Errors are so much instructive and rewarding, and snippets do not cover every user cases, unfortunately. Likewise, autocompletion is great, but only when I need it. Most of the time I know what I want to write and I don’t need a popup window to show complete options. This is why I do not use snippets and set a high time value for autocompletion suggestion.
And here we go with my collection of personal shortcuts. These are Vim mappings, mostly for normal mode, so please adapt to your personal settings:
Keys Description ,x close current buffer - open Netrw ␣x close quickfix, loclist or Trouble window ␣. set current working directory ␣e edit files from current buffer directory ␣E edit in new tab files from current buffer directory tab switch to next tab (cycle) ␣tab create a new tab ␣\$ open a terminal in a new tab C-j go to next quickfix item (also ]q) C-k go to previous quickfix item (also [q) ,s sort current paragraph in lexicographic order (vip:sort u, thanks strager!) zs fix misspelled word using first suggested entry (1z=) ␣d switch dictionary (custom autoload function to alternate between FR and EN dicts)
That’s it, not a big deal. I tend to use built-in shortcuts a lot because I learned the hard way that most often than not, default settings are good.
In Vim, my leader key is <space> (␣) and my localleaderkey key is ,. I tend to use the leader key for installed plugins, while the localleader is used for custom settings or to remap commands I use a lot. Of note, my CAPS lock key is remapped system-wide to (so ,<esc> is equivalent to ,<caps> to hide all other buffers in split view). As I said these mappings are mostly for normal mode. I only use <C-e> and <C-a> in normal and command mode, because these shortcuts are wired in my hands because readline’s everywhere. I tend to use the same mapping in lower and upper case for related tasks. I recently replaced all my Fzf setup with Telescope (see my previous post). I prefer to use the quickfix window rather than the loclist or Telescope for specific task, but I can display the quickfix list in Telescope as well. My complete Telescope mappings are shown below:
utils.map('n', '<leader><leader>', '<cmd>Telescope buffers<CR>')
utils.map('n', '<leader>!', '<cmd>Telescope commands<CR>')
utils.map('n', '<leader>/', '<cmd>Telescope current_buffer_fuzzy_find<CR>')
utils.map('n', '<leader>?', '<cmd>Telescope live_grep<CR>')
utils.map('n', '<leader>*', '<cmd>Telescope grep_string<CR>')
utils.map('n', '<leader>:', '<cmd>Telescope command_history<CR>')
utils.map('n', '<leader>f', '<cmd>Telescope find_files<CR>')
utils.map('n', '<leader>G', '<cmd>Telescope git_commits<CR>')
utils.map('n', '<leader>g', '<cmd>Telescope git_status<CR>')
utils.map('n', '<leader>h', '<cmd>Telescope help_tags<CR>')
utils.map('n', '<leader>q', '<cmd>Telescope quickfix<CR>')
utils.map('n', '<leader>r', '<cmd>Telescope oldfiles<CR>')
utils.map('n', '<leader>w', '<cmd>Telescope treesitter<CR>')
Note that Telescope respects autochdir, so it will limit itself to the current working directory if that option is set to true. As we are generally interested in considering the root directory of a project if there is one, you can use the following mappings as a workaround: (this of course assumes that your project lives in a Git repo)
vim.cmd[[nnoremap <leader>f <cmd>lua require('telescope.builtin').find_files{ cwd = vim.fn.systemlist("git rev-parse --show-toplevel")[1] }<cr>]]
vim.cmd[[nnoremap <leader>. <cmd>lua require('telescope.builtin').live_grep{ cwd = vim.fn.systemlist("git rev-parse --show-toplevel")[1] }<cr>]]
However, my own shortcut <space>e was devised long ago to handle the general CWD issue with Vim. So if you are using the above setup, provided autochdir is not explicitly set to true, you should be able to use Telescope to browse your project while <space>e, after eventually setting the root directory using <space>., would open or create file in the same directory as the current buffer or in the root directory previously defined.
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https://www.arxiv-vanity.com/papers/1608.06198/
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arXiv Vanity renders academic papers from arXiv as responsive web pages so you don’t have to squint at a PDF. Read this paper on arXiv.org.
# Quantum Control Landscapes are Almost Always Trap Free: A Geometric Assessment
Benjamin Russell Department of Chemistry, Princeton University Herschel Rabitz Department of Chemistry, Princeton University Re-Bing Wu Department of Automation, Tsinghua University
April 12, 2020
###### Abstract
A proof is presented that almost all closed, finite dimensional quantum systems have trap free (i.e., free from local optima) landscapes for a large and physically general class of circumstances. This result offers an explanation for why gradient-based methods succeed so frequently in quantum control. The role of singular controls is analyzed using geometric tools in the case of the control of the propagator, and thus in the case of observables as well. Singular controls have been implicated as a source of landscape traps. The conditions under which singular controls can introduce traps, and thus interrupt the progress of a control optimization, are discussed and a geometrical characterization of the issue is presented. It is shown that a control being singular is not sufficient to cause control optimization progress to halt, and sufficient conditions for a trap free landscape are presented. It is further shown that the local surjectivity (full rank) assumption of landscape analysis can be refined to the condition that the end-point map is transverse to each of the level sets of the fidelity function. This mild condition is shown to be sufficient for a quantum system’s landscape to be trap free. The control landscape is shown to be trap free for all but a null set of Hamiltonians using a geometric technique based on the parametric transversality theorem. Numerical evidence confirming this analysis is also presented. This new result is the analogue of the work of Altifini, wherein it was shown that controllability holds for all but a null set of quantum systems in the dipole approximation. These collective results indicate that the availability of adequate control resources remains the most physically relevant issue for achieving high fidelity control performance while also avoiding landscape traps.
## 1 Introduction: Control Landscape Analysis
The study of quantum control landscapes (i.e., specific objective cost that depends on the of quantum time evolution operator as a function of an external field) is a topic of prime interest for assessing the viability of reaching a desired control outcome. As background, prior work has focused on applying differential geometry to several issues in quantum optimal control and quantum mechanics generally [1, 2, 3, 4, 5, 6, 7, 8, 9]. Other recent work [10] has also focused on applying geometric and Lie algebraic methods to controllability in quantum systems. Following similar principles, in this paper geometric methods are brought to bear on the analysis of quantum control landscapes. Specifically, we apply the geometric understanding of the ‘size’ (measure) of the set of singular values of smooth maps (Sard’s theorem [11]) to quantum control landscapes. Further, we apply the parametric transversality theorem, ([12] lemma 1, chapter 2) to reach the main conclusion. In particular, the present work facilitates understanding of the wide prevalence of trap free quantum control landscapes seen in practice, while also accommodating the fact that quantum control landscapes possessing traps appear highly atypical.
There has been success, in both experiment [13, 14, 15] and extensive simulation [16, 17, 18, 19] with the application of gradient based (or other local gradient estimation) algorithms in quantum control. The gradient ascent algorithm is sensitive the critical topology of the function being optimized. In particular, gradient ascent can converge to a local optimum if started from specific initial conditions within the basin of attraction. Consideration of this prospect garnered some controversy. In this regard, some potential issues have also been identified [20, 21] and debated [22] which may affect convergence to a global optima on the control landscape for specific systems. It has been shown that the presence of singular controls [23, 16, 20, 21, 22] can encumber the gradient ascent procedure in some very specific systems, all of which had to be specially constructed to have this unfavorable property. For the definition of singular controls, see sec. (2) and the appendix (A). Particularly the case of constant, or even zero, control fields has received attention [20, 21], partly because of the tractability of analyzing this case. Some examples of non-constant singular controls have been found numerically in [23], but they were all found to be saddles rather than local optima. There is also mounting numerical evidence that situations where singular controls inhibit progress during the gradient ascent procedure are, in several senses, rare [23, 24, 25, 14]. This collected evidence for the common ease of quantum control optimization, and the evident rarity of landscape traps motivated the pursuit of the central result of the present paper.
Finally we note that this work does not address the rate of convergence to the global optima and that this issue is also dependent on the particular search algorithm employed. Some numerical efforts demonstrated that a favorable rate of convergence is typically the case and remains so as the number of levels rises [26, 18, 19].
### 1.1 Summary of The Central Theorem Established in this Paper
Here we first summarize the key finding in this paper, followed by a detailed proof and discussion of the result. In particular we show that only a null set of quantum systems (within the space of all systems with a given number of levels) possess traps caused by singular critical controls. The sense in which this set is null can be understood as follows: if quantum systems are generated at random there is zero probability of finding an example with any singular traps. For a rigorous introduction to the analysis of measures and null sets, see [27].
The crux of the proof rests on a novel application of the parametric transverality theorem from differential geometry [28]. This result has significant implications for quantum control, which can be expressed informally by the following statement:
Consider a parameterized family of time dependent Hamiltonians which depend on finitely many control variables and finitely many real additional parameters . If, for all and (other than those corresponding to the global optima of the fidelity function), it is possible to increase fidelity by applying variations to and respectively, then it follows that the landscape as a function only of , is trap free for almost all fixed values of (i.e., for all but a null set of values).
This informal statement assumes that there is a physically suitable fidelity function quantifying the ‘cost’ of a Hamiltonian driven time evolution. For the above statement to hold, it is also required that the chosen fidelity function does not possess traps of its own, i.e. built into its mathematical structure. This circumstance is the case for many fidelity functions in popular use [29]. An example of a parameterized family of quantum systems, which could be assessed using the above boxed statement is given below:
H[En,λm](t) =(λ0λ1λ1−λ0)+E0sin(t)(0110) (1) +E1cos(t)(0i−i0)+(E2sin(2t)+E3cos(3t))(100−1)
The key implication of the results in this work is that gradient ascent methods will almost always succeed (independent of any initial guess for a control) for optimizing quantum dynamics (i.e., discovering a pulse of maximal fidelity) for almost all quantum systems. This conclusion applies to quantum systems with any finite number of levels. The result has practical significance for finding optimal control fields in simulation as well as in learning control experiments [30] attempting to discover shaped pulses which maximize fidelity in the laboratory. Such experiments, whether guided with a gradient procedure or an other suitable method are essentially a laboratory realization of the analogous simulation, wherein, a control pulse is systematically updated using the algorithmic rule until a high fidelity pulse is found. Henceforth in this work, the distinction between a control function , and vector of control variables will be suppressed unless the distinction is vital.
No attempt is made in this work to address the size of the basin of attraction of local traps in any given quantum control landscape. This interesting and important question is assessed in [16] where it is found that the attractor basin of traps in a few specific examples are small in an appropriate measured sense.
### 1.2 Quantum Systems and the Goals of Control
This paper studies the control of the quantum propagator for finite level quantum systems with Hamiltonians of the form:
^H(t)=^H0+E(t)^Hc (2)
where both the drift and control Hamiltonians are, respectively, traceless and is drawn from a finite, but potentially very high dimensional parameterized space of time dependent control fields. The traceless condition is taken in order that only evolution operators need to be considered rather than , which contains information about a physically redundant overall phase. For a more detailed discussion about the distinction between and with respect to singular controls and the effect of this specialization on the control landscape see [20, 31].
Initially this work studies the maximally controlled system, for which every Hamiltonian matrix element considered as under control; in this circumstance it is reasonably shown that the landscape is trap free. Importantly, incrementally reducing this latter high degree of control back down to the form of (2) is shown to introduce no traps, unless the reduction procedure is engineered to do so by fixing particular matrix elements to specific values within a set shown to be null at each step of the procedure.
In the case of controlling the propagator of a quantum system, the fidelity can be represented by a functional to be optimized:
F1[E]=R{Tr(^G†^UT)} (3)
where is some fixed final time and a target unitary. A phase independent version of this function is given by:
(4)
For several applications of this functional and further discussion see [20, 31]. These functionals both have the form:
F[E]=J(VT[E]) (5)
where is defined as (for example) and is the end-point map, that assigns to a control to the final time propagator which solves the corresponding Schördinger equation at time . The overall conclusion of the paper applies equally to both cost functions which have been shown to both possess only global and local maxima and saddle points [31].
Throughout this paper will be assumed to be large enough for the system to be fixed time controllable, that is to say, for any end-point unitary , there is a control which implements it in time . This property is also referred to as accessibility, it compliments the property of straightforward controllability, which states that: for each end-point unitary , the exists a control which implements at some final time . i.e., there exists at least one control such that for any given . A proof of the existence of such a time , which includes our present case, is given in ([32] theorem 30, Ch. 3).
There are several common objectives in quantum control. These can be broadly classified physically as:
1. Maximizing the expectation of a given (Hermitian) observable at time
2. Controlling an initial quantum state to reach a desired quantum state at time
3. Controlling the quantum propagator so that it is driven to a desired goal . In quantum information sciences applications is typically interpreted as implementing a quantum gate.
Although we will focus on the third of these objectives, the conclusions in this work apply to all of the above tasks as the objective function in the cases (1), (2) can be expressed as a function of the quantum propagator . For a discussion of the correspondence between tasks (2) and (3) from a geometric perspective, see appendix (C.1).
### 1.3 The Gradient Algorithm and the Prospect of Encountering Traps
Employment of the gradient algorithm to determine a control that maximizes fidelity naturally requires the computation of the gradient of the functional . The gradient of the functionals (3), (4) can be computed in closed form [33]. The variation of the end point w.r.t. the full Hamiltonian is given by:
δUT=UT∫T0U†tiδH(t)Utdt (6)
For more complex forms of control coupling, the gradient is not as simple when non-linear coupling to a control field is included, as in the case of control via polarizability [34]. However, this case is essentially the same as the first variation of the end point map with respect to the control in the linear coupling case, except, takes a different form. For further discussion of gradient decent/ascent methods see [35]. Employment of the gradient algorithm is important for understanding the topology of both the set of critical points, and that of the local (if any exist) and global maxima, as exemplified in figure (1).
Here we fix terminology relating to traps in the control landscape of a quantum system.
• A control is called a critical control or a critical point w.r.t. a given , if .
• A control is called a a second order critical point w.r.t. a given if (i.e., a critical control) and the Hessian is negative semi-definite. Such an may or may not be a true local optimum (i.e., a trap) depending on the nature of the higher derivatives with respect to .
• A control is called a trap w.r.t. a given if it is a local, but not global optima of the same .
### 1.4 The Three Assumptions of Landscape Analysis
There are three key assumptions of landscape analysis (see table 2), which are known to be sufficient for a quantum control landscape to be trap free. A clear statement, both in control theoretic and differential geometric terms, can be found in section (5). A key result in much of the recent work in landscape analysis is that these three assumptions imply that the gradient algorithm will converge to a globally optimal control without getting ‘stuck’ in a local optima (i.e., a trap). There is numerical evidence [18, 19] that this hypothesis holds with a wide scope of validity as well as experimental evidence [14, 15, 36, 37].
Earlier important work [10] has shown that the controllability assumption (1) in Table (2) discussed later is almost always satisfied given a pair . That is, the set of Hamiltonians for which controllability fails is a null set. It is however, an open problem to completely characterize the set on which controllability fails. The two most widely applied and useful criteria for controllability are the Lie algebra rank condition (LARC) and the connected graph criterion [10]. A clear example for numerically checking controllability by the Lie algebra rank condition can be found in [38] where an insightful graphical representation of the process is presented. However, only limited work has been performed on the the satisfaction of the local surjectivity assumption (2) in Table (2) and its impact on the performance of gradient algorithms. In this work we present an analogous result to that of [10] for controllability, which applies to the local surjectivity assumption (2). In addition, the final assumption (3), is that there are sufficient control resources (i.e., the control space is sufficient for the end-point map to be globally surjective) to freely explore the landscape. The new result, considering all three assumptions, explains why gradient ascent convergence to a global optimum is so typical in practice despite the fact that some engineered special examples with traps are known.
## 2 Singular Controls and Properties of the End-Point Map
### 2.1 Kinematic and Dynamical Optima
The scenario here concerns discovering a control scheme driving the time evolution operator to a desired goal at time (i.e., ). This process is represented by the following commutative diagram,
is an objective function to maximize, and is a pre-defined space of control fields. Applying the chain rule to yields:
δFδE=dJdVT[E]∘δVT[E]δE (7)
• A control is said to be singular if the set of all for which there exists a corresponding (i.e., a value of ) doesn’t span at the point . This is to say that the Fréchet derivative:
δVT∣∣E:δE↦δUT (8)
is not of maximal rank at the point in the space of controls. The co-dimension of the image of given by is called the co-rank of the control.
There are two types of critical points of : ones for which , and those for which is not of full rank in . Consideration of is referred to as the kinematic control landscape and is referred to as the dynamic control landscape. Figure (2) clarifies the relationship between the kinematical and dynamical landscapes. Ultimately, the goal is to understand if singularities of can introduce critical points of which are not critical points of , i.e. singular controls which introduce new critical points into the landscape of . Understanding which systems have no such singular critical controls will elucidate the circumstances for which the critical point structure of and are the same. For these systems an analysis of the kinematic landscape alone suffices to understand the full control landscape of . This is a desirable goal as it facilitates reaching the conclusion that one only needs to consider the prospect of traps arising directly from a fidelity function, and thus that an appropriate choice of fidelity function is sufficient to result in a trap free landscape [29].
With the remarks above in mind we make the following definitions and observation:
• A Kinematic Critical Point is a control such that .
• A Dynamic Critical Point is a control such that .
It is clear from eqn. (7) that all kinematic critical points are dynamic but that the converse is not true unless is full rank for all . It is important to understand the nature of both types of critical points. Ultimately, the most salient question is: do singular controls introduce local optima into quantum control landscapes and if so, what is the practical ramifications of this both in simulations and laboratory learning control [30] scenarios?
### 2.2 Vt is a smooth map
Here properties of needed in order to apply the parametric transversality theorem are established. Considering controls only drawn from either or any finite dimensional vector space of smooth functions, has the properties of being a smooth function of , a smooth function of and a smooth function of and . We use this fact without giving a proof, however a proof can be given by using the so called ‘convenient calculus’ [39]. The proof is long and involved as well as a direct parallel of many existing proofs, so it is omitted. We further observe, by the smoothness of the matrix exponential and of matrix multiplication, that the end-point map is also smooth on any space of piecewise smooth controls. This fact will be required in ensuing geometric analysis.
## 3 Climbing the Landscape: Transverality to the Level Sets of J is Sufficient to Climb
This section will show the failure of local surjectivity will not necessarily cause a gradient assent to halt. We show that a significantly weaker condition rather than local surjectivity is sufficient to exclude traps, namely: being transverse to the level sets of the fidelity function. We also argue that the set of Hamiltonians for which a search will halt are a null set under some physically reasonable assumptions.
### 3.1 Transversality
Firstly, the concept of transversality is introduced as an abstract property of smooth maps between manifolds. Secondly, the end point map is shown to possess the property of transversality by taking specific instances of the manifolds in the definition of transversality.
The gradient of a smooth function on a smooth manifold is always perpendicular to level sets of this function (if the same Riemannian metric is used throughout). If local surjectivity of fails somewhere on a specific level set of on , it may not matter as far as climbing the landscape when using gradient assent. All that matters is an ability to ascend the landscape, not necessarily to traverse the level set itself. If there does not exist a which causes to vary in a specific direction within the level set of containing , this is not problematic for gradient ascent, but would still indicate the failure of surjectivity. A control may be singular, even up to co-rank of the dimension of the level sets of containing , but as long as there exists a such that has a non-zero component in the direction of the gradient on , then it will not impair the ability to climb the landscape (i.e., increase ) by introducing a small variation of . With this in mind, we state the following definition of a transverse map:
• , Given two smooth manifolds, , a submanifold , and a smooth map (with ), is called transverse to (denoted ):
Image(dϕ∣∣p)⊕Tϕ(p)L=Tϕ(p)M ∀p∈ϕ−1(L) (9)
The concept above is illustrated in figure (3). In this work, only the case that is globally surjective (i.e., an onto function) will be important. This case corresponds to only considering controllable systems. This renders redundant the condition that is a subset of the image of because the image of is the whole of for quantum systems which are fixed time controllable. The results reported in [10] and (Theorem 12, Chap. 6 [32]), can be paraphrased as: for almost all , is globally surjective.
## 4 Applying the Parametric Transversality Theorem to Quantum Control
In this section we will utilize the parametric transversality theorem as the key to facilitate proving the rarity of quantum systems with traps. The proof of this theorem (which follows from Sard’s theorem [11]) is complex and is omitted, but well known within differential geometry.
Here the statement of the parametric transversality theorem is given prior to it’s application to quantum control.
###### Theorem 4.1 (Parametric Transversality Theorem, [12] lemma 1, chapter 2)
Given smooth manifolds, and , a submanifold , and a parameterized family of smooth maps where (parameterized by ), then if defined by: is transverse to (when variations of are considered), then almost all values of have transverse to . Furthermore, the pre-image of is a submanifold of with codimension in equal to the codimension of in .
The following result of differential geometry aids in building intuition about Theorem 4.2:
Given a family of smooth maps parameterized (by drawn from a smooth manifold), for almost all values of s, is transverse of a given submanifold if the family as a whole is transverse to the same .
It is also clarifying to note that if , then a map being transverse to is equivalent to it being locally surjective.
The parametric transversality theorem can be applied to the case of quantum control landscapes for finite level systems. One can set to be a (finite, large dim, manifold of control fields), to be and to be any level set of , the cost functional. In order to analyze the quantum control landscapes, is given by (for some fixed ). The parameter (the set of maps ) can be taken to parameterize values in a set of (potentially time dependent) Hamiltonians. For each time dependent Hamiltonian , there is an end-point mapping . This is clarified in equation (10) below and within the ensuing discussion.
### 4.1 The Central Theorem
In this section we apply the parametric transversality theorem to a large class of quantum control problems. We show that this analysis allows one to conclude that only a null set of quantum systems have singular critical points.
In this section we denote by , a high but finite, dimensional space of control fields taken to consist of piecewise constant (with pieces) functions bounded in magnitude by . We will denote by a basis for this space, and by an orthonormal basis of .
Consider, initially, the scenario of having total control over a system’s Hamiltonian as a function of time (i.e., all matrix elements under control) within the confines of the space , one can then show that successively restricting the degree of control does not generically introduce any singular critical points. The ensuing physical and mathematical argument in no way rests on the assumption that all such Hamiltonians can be created in the laboratory in practice. We initially postulate the existence of such a rich space of control fields and the full degree of coupling permitted by these fields, and then progressively restrict the degree of control while assessing the effect that each restriction has on traps in the landscape. Specifically, we initially study every curve of the form:
iH(t)=∑jfj(t)Bj=∑j,kaj,k gk(t)Bj (10)
as a Hamiltonian where is given by:
gk(t)={1 Tkp≤t≤T(k+1)p,0 else (11)
The case of a Hamiltonian with drift and control , referred to in the single (piecewise constant) field dipole approximation, is included within the above form (10). It is now clear that there exists such that the end-point map is surjective as a map from for some values of . Applying a variation , the end point change becomes:
U†TδUT =∫T0U†tδ(iH(t))Ut dt (12) =∑j,k∫T0δaj,k gk(t) U†tBjUt dt
Assuming that is an orthonormal basis of , the duration of each piecewise constant segment of the control is short enough (i.e. is large enough) and the speed of the curve is not too high (i.e. is small enough), then the set is also a (not necessarily orthonormal) basis of . Here is the piece defined by . To understand exactly what is meant be ‘short enough’, one must understand the singularities of the matrix exponential (C). This implies that any variation can be created by some variation admissible within this space of piecewise constant controls, and thus that the end-point map is locally surjective everywhere on this space of controls.
Adopting the above premises, one can now apply the parametric transversality theorem to conclude that fixing the value of any one of the control the parameters to a given constant will not introduce singular critical points into the landscape for all but a null set of fixed values.
###### Theorem 4.2
For a system with with Hamiltonian of the form (10) and space of piecewise constant controls as above such that the end-point map is locally surjective everywhere in the control space, fixing any single control parameter introduces singular critical points into the new control landscape (a function of the remaining, unfixed variables only) only for a null set of values of .
• Let be the end point map of the Schrödinger equation. This map can be considered to depend on , as these parameters are sufficient to determine , so we will denote the end-point map accordingly. As such, (i.e., one control field for each ) where we have taken to be sufficient for to be surjective as explained above. This is equivalent to saying: , which in turn implies: is transverse to every sub-manifold of . Henceforth, will have left unwritten, assumed to have these values taken so that is locally surjective everywhere in its domain.
We can now decompose the domain of into two parts by selecting one parameter , and considering as a one parameter family of maps of the remaining variables . One can now apply the parametric transversality theorem by considering the values of as , the values of the remaining variables as and as and conclude that only a null set of values cause this new restricted map to fail to be locally surjective.
Given theorem (4.2), one can assume that one value has been fixed to a specific value not in the null set of values which introduce singular critical points. Fixing another , and applying an identical argument, one finds that only a null set , introduce singular critical points. This process can now proceed inductively. Note that these null sets need not be the same set of values. Proceeding by induction, one sees that fixing any number of the free parameters describing the system, does not introduce singular critical points except for a null set of fixed values at each step. It may, however, cause the end-point map to fail to be globally surjective, the property generically preserved by fixing parameters is that of being locally surjective within in image of , without reference to what that image is. This eventual breakdown of global surjectivity corresponds to loss of controllability and thus a shrinking of the reachable set.
We have shown that local surjectivity, which implies transversality to the level sets of any smooth function, only fails for a null set of quantum systems. This technique can be applied to show that transversality of to the level sets of a specific objective function is also generic. Considering a family of systems parameterized by a vector of numbers (for example: the coupling constants of a spin chain system controlled by a magnetic field). Then, by a nearly identical argument, if is transverse to a given level set of fidelity when variations of both and are admissible, then all but a null set of fixed values of leave transverse to the same set when only variations of are considered. We further note that the argument of the central theorem does not rest on the initial appeal to a space of piecewise constant controls. The assumption of a finite dimensional space of controls is physically unrestrictive as the space of controls can be given a very high dimension leaving the space of control fields still including all those which can be physically implemented. One way to achieve this truncation of control space, is to only consider control fields with ‘bounded variation’ (band limited in the terminology of Fourier series). Such control fields possess no frequencies above a certain critical frequency. If this critical frequency is high enough, then any discarded component of the control field would not affect the time evolution differently from noise. An identical argument could be made if one started with any finite dimensional space of controls which can be shown to render the end-point map locally surjective.
The following table 1 clarifies the correspondence between the abstract statement of the parametric transversality theorem (PTT) and its application to quantum control.
### 4.2 Context and Physical Relevance
The result of section (4.1) is a parallel of the central result of Altifini [10]. Altifiti’s key result can be restated as: for almost all (i.e., all but a null set) the map is globally surjective (onto) on . Clearly, this result includes cases with more than one control field as it applies to the case with only a single control field and adding additional control fields cannot destroy controllability. In the same spirit, the conclusion of section 4.1 is that almost all Hamiltonians will not produce singular traps.
It has been discussed in [34] that while many practical control scenarios are described by a Hamiltonian in the dipole approximation, laboratory scenarios can include more complex forms of coupling. As such, the mathematical existence of traps in systems in the dipole approximation, does not necessarily translate into the existence of traps in laboratory experiments. Complex (non-linear) coupling of control fields within the system’s Hamiltonian and coupling to the environment can be present in reality, even if they are only very small. Noise in the control field is also present in practice. If fixed values of complex coupling to external fields are chosen at random, with certainty traps will not be present in the landscape. This implies that, if a well validated model of a quantum system is shown to possess traps, even the least inaccuracy in the model or the presence of any additional types of coupling to the control fields, will very likely remove these traps by effectively perturbing the Hamiltonian matrix elements out of the failing set.
### 4.3 Numerical Confirmation
In order to confirm the conclusions, of the central Theorem 4.2, numerical simulations were run. pairs (i.e., four level systems) were generated at random and optimizations with random initial controls were run using a gradient ascent algorithm. The control fields tested were defined to be piecewise constant with pieces with appropriately bounded magnitude, as per the central result above. Initially, a singular control was generated at random (see appendix 24) by choosing at random (i.e., a procedure specifically seeking a singular control, rather than one designed to avoid them). The bounded magnitude premise of the central theorem was imposed via rejection sampling on . We will denote by the control created from formula 24 with a given value of (with normalized s.t. ). The time evolution simulation is given by:
dUtdt=(a+E(t)b)Ut (13)
Stochastic gradient ascent (over ) was then run to maximize the quantity:
⟨B, U†T∇J∣∣UT⟩ (14)
One readily confirms that this quantity will be maximized for a singular critical point and at no other point. It was found that in all generated cases , no singular critical controls consistent with the magnitude bound premise of Theorem 4.2 were discovered as the algorithm did not converge. As many initial conditions were tested, this is strong numerical confirmation that such controls do not exist.
## 5 Discussion and Conclusions
Theorem 4.2 has been presented describing the structure of typical quantum control landscapes by introducing a novel tool from differential geometry extracted from the parameteric transversality theorem. The technique used to obtain Theorem 4.2 is novel, and potentially has scope well beyond quantum control. We have shown that quantum systems with singular critical controls are rare in the space of all possible quantum control systems, i.e., all systems evolving under the Schrödinger equation with some coupling to external control fields. In order for the transversality result to apply specifically to the dipole approximation with a single field it would be required to show that the restrictions on the maximally controllable Hamiltonian do not leave the remaining Hamiltonian within the null set possessing traps. However, as the set possessing traps is null, there exists a perturbation to any controllable system possessing traps, which removes them. We have further formalized a sufficient condition for systems with singular critical points to possess no second order critical points (B). Attempting to show that this condition almost always holds will be the focus of further work also based on the parametric transversality theorem.
We have refined the surjectivity assumption of quantum control landscape theory to that of transversality. We argued that the end point map being transverse to all level sets of fidelity is sufficient for the dynamical and kinematical landscapes to share the same critical point structure. A novel technique for showing that a very large class of realistic systems possess this property was also presented.
The original and current status of the three assumptions of quantum control landscape analysis are given here, so that the new and original forms and statues of each can be compared.
It is possible to check that these assumptions imply that the dynamical landscape almost always possess the same critical point structure as the kinematical one. This can be achieved by observing that the composition of two functions, , has the same critical point structure as that of if satisfies both transversality and globally surjectivity. Finally, we note in the current assumptions of Table 2 that assumptions 1 and 2, are almost always satisfied. As a result, it is clear that the primary determining factor for the ease for optimization in quantum control, for the vast majority of Hamiltonians, is the availability of sufficient control resources, assumption (3).
We also note that transversality only requires that the end-point map has rank 1 and the is contained within its range. This is in contrast to the requirement that is full rank, because full means that the rank is equal to the dimension of the group , which is . The condition that local surjectivity be satisfied becomes more demanding on the rank of as the number of level rises, which is in contrast to transversality.
## 6 Acknowledgments
The authors would like to thank Robert Kosut for many helpful discussions and comments during the drafting of this work, and Daniel Burgarth for some corrections. Benjamin Russell acknowledges the support of DOE (grant no. DE-FG02-02ER15344. Herschel Rabitz acknowledges the support of the Army Research Office (Grant No. W911NF-16-1-0014). We also acknowledge partial support from the Templeton foundation.
## Appendix A Singular Controls in the Dipole Approximation and Beyond
Here we give formulas for singular controls in the case of a single control field in the dipole approximation. In order to express all relevant quantities in terms of Lie algebraic objects in we make the following definitions:
a:=−iH0 (15) b:=−iHc
Much of what is presented in this section and throughout is applicable, appropriately modified, to control systems of the analogous form on compact, connected, semi-simple Lie groups other than .
In this notation, the Schrödinger equation for a controlled quantum system (2) reads:
dU(t)dt=(a+E(t)b)U(t) (16)
The authors are only aware of singular control trapping studies in the dipole approximation expressed here other than in a recent work [34].
It is possible to explicitly express in terms of [40];
δVT[w]=U(T)∫T0δE(t)U(t)†bU(t)dt (17)
The right translation of the is given by:
U(T)†δU(T) =∫T0δE(t)U(t)†bU(t)dt (18) =∫T0δE(t)btdt
where we have defined so that it solves the adjoint equation . We note that this form (i.e., the integral of an adjoint orbit in a Lie algebra) is only possible because we have a Lie group of time evolution operators and that form is unique to such a scenario.
If the control , which drove the system along the trajectory , is singular, then there exists, be definition, at least one such that:
⟨BU(T,0),δU(T,0)⟩U(T,0)=0 ∀δE (19)
where is any inner product on the tangent space and . A convenient choice of inner product is given by the unique (up to a constant multiple) bi-invariant Riemannian metric on . This metric is expressed as the right (or left, as the two coincide) translation of the Killing form :
K(X,Y)=\Tr(X†Y) (20)
The condition that a control is singular can now be written, by applying formulas (18, 19), in terms of this inner product:
K(U(T)†δU(T),B)=0⇒ (21) K(∫T0δE(t)btdt,B)=0⇒ ∫T0δE(t)K(bt,B)dt=0
In scenarios where the set of considered is large enough, one can apply the fundamental lemma of the calculus of variations and conclude that:
K(bt,B)=0 ∀t∈[0,T] (22)
The interpretation of this equation is that infinitesimally varying doesn’t in turn vary in the direction for any time during the evolution. From this result, the form of the singular controls can be deduced by differentiating w.r.t .
Noting that has dropped out as , one differentiates again w.r.t to find:
assuming that the denominator is never zero. If it is zero, further differentiation is required which yields another expression containing higher levels of nested commutators. Another formula can also be obtained by applying a symmetry of the Killing form to obtain from (22)
K(b,Bt)=0 ∀t∈[0,T] (25)
where is defined similarly to above. Closely following [23], the form of the singular controls can be similarly determined in the case of controlling the density matrix.
From formula (24), one sees that not all singular controls are constant. One also observes that there is no reason, a priori, to preclude the possibility of encountering singular controls during gradient ascent for systems in the dipole approximation. However, formula (24) also indicates that there are very few singular controls relative to the size of the total control space. This can be deduced from the one-to-one correspondence between , and singular controls. Given that the dimension of is , and the control space typically will have far larger dimension for an level system, this indicates that singular controls are not prevalent in the control space. If the Hamiltonian contains quadratic coupling to a single control field, a similar implicit formula for a singular control can be found [34] by a like procedure.
## Appendix B Second Order Analogue of the Central Theorem 4.2
The parametric transversality theorem can be applied to the Hessian of the fidelity by defining a new map :
QT(E,δE):=(VT(E),dVT∣∣E(δE)) (26)
where is the push-forward of the map . This approach is appropriate for showing that only a null set of systems, which possess singular critical points, possess second order critical points. Another definition is now needed:
• Given two vector spaces define . That is is the set of rank deficient linear maps from to .
It is now possible to state the condition that a given quantum system has no second order critical points in terms of transversality of the map to a specific submanifold of the range of the same map.
If is the submanifold constructed from the union of all the level sets (of J) which contain a singular critical value of , define a submanifold of as:
L=S×Σ (27)
The condition that there are no second order critical points now reads: , which renders it amenable to assessment via application of the parametric transversality theorem. Checking for which systems this condition holds, and similarly for higher order conditions, will form the basis of further work.
## Appendix C Singularities of the Matrix Exponential
The matrix exponential possess singularities at, and only at, any matrix for which has as an eigenvalue for any . In any quantum system with a piecewise constant Hamiltonian (with pieces of duration labeled as , which are not time dependent), the propagator can be expressed as a product of exponentials:
UT=eδtiH(K)⋯eδtiH(1) (28)
The eigenvalues of are where are the eigenvalues of [41] for any square matrix . If the difference of the highest and lowest magnitude eigenvalue of (which equals the magnitude largest eigenvalue of ) is less that , then the map is locally surjective. If all meet this premise, then clearly the overall end-point map is surjective. If a given does not meet the premise, then reducing sufficiently will restore the premise. Specifically, systems such that:
δt<2π∣∣E(n)max−E(n)% min∣∣ (29)
where is the largest eigenval of (and similarly) for all , will have no singularities.
More generally, the Lie theoretic exponential map, , has the property that it is invertible (i.e., a diffeomorphism) in a neighborhood of , i.e., is invertible near to zero (Corollary 3.44, [42]). This indicates that it is free from singularities, and thus that for piecewise constant controls, with sufficiently small pieces, the end-point map is also free from singularities.
### c.1 The Relationship between Singular Trajectories when Controlling the Propagator and when Controlling a Quantum State
It has been noted in [23] that there exist controls for systems of the type (2) which are singular for the control of the the propagator and not for the control a quantum state. Here we discuss the geometric basis of this finding using the construction of complex protective space as the quantum state space of pure states is a homogeneous space of . We also discuss why this construction has no analogue in the case of a mixed state.
In geometric quantum mechanics the space of pure states, up to equivalence of states by normalization and global phase, is a manifold known as a complex projective space [8]. For other applications of this construction in quantum control see [43, 1, 2]. This relationship can be formally expressed as:
CPn−1≅SU(n)/U(n−1) (30)
where the symbol refers to the quotient of into cosets. The special case of the space , is the familiar Bloch sphere for a qubit. This construction is only possible because acts transitively on , see [44] for details of this construction. As unitary evolution preserves the degree of mixedness of a mixed state, does not act transitively on the manifold of all density matrices representing mixed states. Due to this lack of transitive action (i.e., not all states can be transformed into all others via unitary evolution), this space cannot be represented as a homogeneous space of . Because of this circumstance, it is not as straight forward to form an analogous construction for mixed states.
The space where the quantum state resides is a quotient of the space where the time evolution operator resides. Because of this, each direction in the tangent space at some point in corresponds to more than one direction in the tangent space at some point in . As such, the existence of a direction , which does not correspond to any admissible variation , is not sufficient for such a direction to exist in when the time evolution of the state is standardly defined by . Thus, not all controls of the form (24) are singular for the control of a pure state. This construction provides insight into which controls can be singular for the control of a pure state, as it reveals the exact sense of: several directions in which and be steered by variation of corresponding to a given variation of . Thus, it is clear that not every control which is singular for the control of the propagator is singular for the control a pure state. The practical significance of this result is that if the landscape for the control of the propagator is trap free, then the landscape for the control of the state is also trap free.
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http://www.tug.org/pipermail/texhax/2011-September/018221.html
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# [texhax] \hangindent inside vertical mode
Donald Arseneau asnd at triumf.ca
Thu Sep 29 05:25:02 CEST 2011
VAFA KHALIGHI <vafaklg at gmail.com> writes:
> > On Thu, Sep 29, 2011 at 4:13 AM, Heiko Oberdiek <
> > heiko.oberdiek at googlemail.com> wrote:
> >
> >> On Thu, Sep 29, 2011 at 01:14:33AM +1000, VAFA KHALIGHI wrote:
> >>
> >> > \hangindent-20pt \hangafter0 does not work inside a \vbox. Is the reason
> >> > explained somewhere in The TeXBook?
> >>
> >> Why do you think it does not work?
> >> Because -20pt is less than 0pt, the lines will be indented at
> >> the right side by 20pt.
> >>
> Sorry, this is what I have tried. Giving negatve dimen to \hangindent, only
> reduces the width of the vbox.
But that *IS* working! \hangindent-x works to reduce the width of the
lines, and the enclosing box has the width of the widest thing in
the vertical list. \hangindent does not insert a box, as \indent
does, despite the "indent" in the name.
I take it you were hoping \hangindent worked differently from \parshape,
(as used in lists) but it does not.
Donald Arseneau asnd at triumf.ca
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https://worldwidescience.org/topicpages/l/laguna+don+blanco.html
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#### Sample records for laguna don blanco
1. Calle Blanco
Directory of Open Access Journals (Sweden)
Gonzalo Cerda Brintrup
1988-06-01
Full Text Available Importante arteria, que comunica el sector del puerto con la plaza. Las más imponentes construcciones se sucedían de un modo continuo, encaramándose a ambos lados de la empinada calle. Antes del gran incendio de 1936 grandes casonas de madera destacaban en calle Irarrázabal y en la esquina de ésta con calle Blanco, la más hermosa construcción pertenecía a don Alberto Oyarzún y la casa vecina hacia Blanco era de don Mateo Miserda, limitada por arriba con la casa de don Augusto Van Der Steldt y ésta era seguida de la casa de don David Barrientos provista de cuatro cúpulas en las esquinas y de un amplio corredor en el frontis. Todas estas construcciones de madera fueron destruidas en el gran incendio de 1936.
2. Primeros registros del ibis blanco (Eudocimus albus en el Altiplano de San Luis Potosí, México
Directory of Open Access Journals (Sweden)
Natalia de Gortari-Ludlow
2012-07-01
Full Text Available Reportamos dos observaciones visuales del ibis blanco (Eudocimus albus de la Laguna de Los Coyotes, un afluente natural del manantial la Media Luna que se localiza en el municipio de Rioverde, San Luis Potosí, México. Los avistamientos ocurrieron en septiembre de 2011 y febrero de 2012. Este es el primer reporte de la presencia de esta ave en dicha localidad, y es importante porque la especie ha sido escasamente encontrada en ambientes no ribereños del Altiplano Mexicano.
3. Registro de pecarí de labios blancos (Tayassu pecari en la región de la laguna de Términos, Campeche, México White lipped pecaries (Tayassu pecari recorded in the area of Términos Lagoon Campeche, México
Directory of Open Access Journals (Sweden)
Mircea G. Hidalgo-Mihart
2012-09-01
Full Text Available Se registró fotográficamente al menos un grupo de pecaries de labios blancos (Tayassu pecari en la Selva La Montaña, al suroeste del área de Protección de Flora y Fauna Silvestre Laguna de Términos, Campeche, México. El registro se realizó utilizando trampas cámara. La presencia de esta especie muestra la importancia que tiene la región Selva La Montaña para la conservación de la biodiversidad, especialmente para las especies protegidas.We report at least one group of white lipped peccaries (Tayassu pecari in Selva La Montaña located in the southwestern portion of the Términos Lagoon Flora and Fauna Protection Area, Campeche, Mexico. The record was obtained using camera traps. The presence of this species in the area shows the importance of the region for biodiversity conservation, particularly for protected species.
4. Blanco White and Walter Scott Blanco white y Walter Scott
Directory of Open Access Journals (Sweden)
Fernando DURÁN LÓPEZ
2011-01-01
Full Text Available The first edition of Ivanhoe; a romance. By the author of Waverley was published in Edinburgh in 1820. From the beginning of year 1823, José María Blanco White translated several excerpts from Ivanhoe in the numbers 1-3 of the magazine Variedades, owned by the publisher Rudolph Ackermann. in these articles and other later writings, the translator praised Scott as a model for a new way of painting history in a narrative. This paper studies his ideas on Scott’s historical novel, as well as his translation technique, compared with that of José Joaquín de Mora. En 1820 se publicó en Edimburgo la primera edición de Ivanhoe; a romance. By the author of Waverley. Desde comienzos de 1823, en los tres primeros números de su revista Variedades, promovida por el editor Rudolph Ackermann, José María Blanco White tradujo varios fragmentos de Ivanhoe entre grandes elogios. Asimismo, Blanco White tomó a Scott como modelo de referencia de una nueva manera de pintar la historia por medio de la novela en otros varios escritos críticos de años posteriores. El artículo estudia las ideas de Blanco White acerca de la novela histórica de Scott y su técnica como traductor, comparada con la de José Joaquín Mora.
5. Lithium in Blanco1: Implications for Stellar Mixing
OpenAIRE
Jeffries, R. D.; James, D. J.
1998-01-01
We obtain lithium abundances for G and K stars in Blanco 1, an open cluster with an age similar to, or slightly younger than, the Pleiades. We critically examine previous spectroscopic abundance analyses of Blanco 1 and conclude that while there were flaws in earlier work, it is likely that Blanco 1 is close in overall metallicity to the older Hyades cluster and more metal-rich than the Pleiades. However, we find Blanco 1 has Li abundances and rotation rates similar to the Pleiades, contradic...
6. El Dioscórides de Andrés Laguna en los textos de Cervantes: de la materia medicinal al universo literario
Directory of Open Access Journals (Sweden)
Francisco López-Muñoz
2007-12-01
Full Text Available The literary works of Miguel de Cervantes have been widely studied from numerous points of view, including the medical one. In the present work, we defend the hypothesis that the Andrés Laguna version of Dioscorides was the source used by Cervantes in his literary passages related to therapeutic aspects, especially in relation to plants with medicinal properties. This book, a copy of which was in Cervantes’ private library, is the only medical treatise cited by the novelist in any of his writings (Don Quixote. Apart from the medicinal plants mentioned in his works, of which we have identified chicory, oleander, henbane, opium poppy, rosemary, rhubarb, tobacco, tamarisk, seeds of spurge, and vervain, Cervantes also seemed familiar with the effects of different pharmaceutical preparations produced from plants (white ointment, Aparicio’s Oil, narcotic powders, etc.. Our hypothesis is backed up by Cervantes’ use of descriptions similar to those of Laguna in his Dioscorides (the hallucinogenic effects of witches’ ointments in The Colloquy of the Dogs, the therapeutic properties of rosemary in the treatment of wounds and traumatisms in Don Quixote, the narcotic effects of opium in The Jealous Extremaduran, the psychodysleptic effects of some love potions in The Licentiate of Glass, or the toxic effects of some poisons in The Spanish-English Lady, and even, in some cases, by use of Laguna’s similar quotations (as in his reference to the purging of excessive bile in Don Quixote.
7. Backwater Flooding in San Marcos, TX from the Blanco River
Science.gov (United States)
Earl, Richard; Gaenzle, Kyle G.; Hollier, Andi B.
2016-01-01
Large sections of San Marcos, TX were flooded in Oct. 1998, May 2015, and Oct. 2015. Much of the flooding in Oct. 1998 and Oct. 2015 was produced by overbank flooding of San Marcos River and its tributaries by spills from upstream dams. The May 2015 flooding was almost entirely produced by backwater flooding from the Blanco River whose confluence is approximately 2.2 miles southeast of downtown. We use the stage height of the Blanco River to generate maps of the areas of San Marcos that are lower than the flood peaks and compare those results with data for the observed extent of flooding in San Marcos. Our preliminary results suggest that the flooding occurred at locations more than 20 feet lower than the maximum stage height of the Blanco River at San Marcos gage (08171350). This suggest that the datum for either gage 08171350 or 08170500 (San Marcos River at San Marcos) or both are incorrect. There are plans for the U.S. Army Corps of Engineers to construct a Blanco River bypass that will divert Blanco River floodwaters approximately 2 miles farther downstream, but the 60 million price makes its implementation problematic. 8. Caminhos da intersubjetividade: Ferenczi, Bion, Matte-Blanco Paths of intersubjectivity: Ferenczi, Bion, Matte-Blanco Directory of Open Access Journals (Sweden) Ignácio Gerber 1999-01-01 Full Text Available A Intersubjetividade é inerente à concepção freudiana de Psicanálise, mas foi Ferenczi, seu discípulo mais próximo, o pioneiro na investigação das emoções que tomam o analista na presença do analisando. Esse artigo retoma aspectos dessa investigação das próprias emoções em Ferenczi, Bion e Matte-Blanco, discutindo as relações entre a lógica racional consciente e essa outra lógica emocional e contraditória do Inconsciente.Intersubjectivity is pertinent to the freudian concept of Psychoanalysis. Yet, it was Ferenczi, his closest disciple, and the pioneer in the investigations of emotions, which come upon the analyst in the presence of the patient. This paper retakes the aspects of this investigation of Ferenczi, Bion and Matte-Blanco, discussing the relations between the rational logic and this other one which is the emotional and contradictory logic of the unconscious. 9. Dark Energy Camera for Blanco Energy Technology Data Exchange (ETDEWEB) Binder, Gary A.; /Caltech /SLAC 2010-08-25 In order to make accurate measurements of dark energy, a system is needed to monitor the focus and alignment of the Dark Energy Camera (DECam) to be located on the Blanco 4m Telescope for the upcoming Dark Energy Survey. One new approach under development is to fit out-of-focus star images to a point spread function from which information about the focus and tilt of the camera can be obtained. As a first test of a new algorithm using this idea, simulated star images produced from a model of DECam in the optics software Zemax were fitted. Then, real images from the Mosaic II imager currently installed on the Blanco telescope were used to investigate the algorithm's capabilities. A number of problems with the algorithm were found, and more work is needed to understand its limitations and improve its capabilities so it can reliably predict camera alignment and focus. 10. Heating effects in Rio Blanco rock International Nuclear Information System (INIS) Taylor, R.W.; Bowen, D.W.; Rossler, P.E. 1975-01-01 Samples of ''sandstone'' from near the site of the upper Rio Blanco nuclear explosion were heated in the laboratory at temperatures between 600 and 900 0 C. The composition and amount of noncondensable (dry) gas released were measured and compared to the amount and composition of gas found underground following the explosion. The gas released from the rock heated in the laboratory contained approximately 80 percent CO 2 and 10 percent H 2 ; the balance was CO and CH 4 . With increasing temperature, the amounts of CO 2 , CO, and H 2 released increased. The composition of gas released by heating Rio Blanco rock in the laboratory is similar to the composition of gas found after the nuclear explosion except that it contains less natural gas (CH 4 , C 2 H 6 . . .). The amount of noncondensable gas released by heating the rock increases from approximately 0.1 mole/kg of rock at 600 0 C to 0.9 mole/kg at 900 0 C. Over 90 percent of the volatile components of the rock are released in less than 10 h at 900 0 C. A comparison of the amount of gas released by heating rock in the laboratory to the amount of gas released by the heat of the Rio Blanco nuclear explosion suggests that the explosion released the volatile material from about 0.42 mg of rock per joule of explosive energy (1700 to 1800 tonnes per kt). (auth) 11. El destierro infinito de Blanco White en la mirada de Juan Goytisolo Directory of Open Access Journals (Sweden) Durán López, Fernando 2010-06-01 Full Text Available In the years 1970-1972, the novelist Juan Goytisolo published several studies and translations on the work of José María Blanco White, which represent a key moment in the recovery of that forgotten writer for the modern Spanish culture. The argument made in this essay is that the consciously identifying strategy applied by Goytisolo on Blanco White, in order to define a Spanish intellectual tradition throughout the centuries, marked by exile and dissent, is in fact a deformation of the figure and thought of the writer from Seville. Blanco White’s reception in Spain, however, has been conditioned by that reading.En torno a los años 1970-1972 el novelista Juan Goytisolo publica varios estudios y traducciones sobre la obra de José María Blanco White, que suponen un momento clave en la recuperación de ese olvidado escritor para la moderna cultura española. La tesis formulada en el presente artículo es que la estrategia conscientemente identificadora que aplica Goytisolo sobre Blanco White, a fin de definir una tradición intelectual española a lo largo de los siglos marcada por el exilio y la disidencia, supone de hecho una deformación de la figura y el pensamiento del escritor sevillano. La recepción de Blanco White en España ha quedado, sin embargo, condicionada por esa lectura. 12. Start-up and operation of Laguna Verde-2 International Nuclear Information System (INIS) Torres Ramirez, J.F. 1996-01-01 The 665 MWe Laguna Verde-2 nuclear generating unit was accepted into commercial operation on April 10, 1995. The boiling water reactor plant by General Electric (GE) was first synchronized with the grid on November 11, 1994. Laguna Verde-2 is identical with Laguna Verde-1 on the same site. That unit had gone critical for the first time in November 1988 and had first been synchronized with the power grid on April 13, 1989. Commercial operation of Laguna Verde-1 had been started on July 29, 1990. Mexico's only nuclear power plant had been built 70 km north of Veracruz on the east coast and had been scheduled to start operation in 1976. As the Mexican nuclear power program was reduced, the scheduled commissioning dates suffered more and more delays. In the full of 1987, the investigation by the Operational Safety Review Team (Osart) of the International Atomic Energy Agency (IAEA) had indicated that the safety requirements of installations and equpiment were met, and that the whole plant was well prepared for fueling. In mid-1988, the Mexican Government had issued the permit to fuel the Laguna Verde-1 reactor. The contract to build the two units had been awarded in 1972/73. No other nuclear power plants are currently under construction or in the planning phase in Mexico. (orig.) [de 13. Komposisi dan Kemelimpahan Fitoplankton di Laguna Glagah Kabupaten Kulonprogo Provinsi Daerah Istimewa YOGYAKARTA OpenAIRE Ramadani, Aisyah Hadi; Wijayanti, Arini; Hadisusanto, Suwarno 2013-01-01 Penelitian bertujuan untuk: 1) mengidentifikasi jenis fitoplankton di laguna Glagah; 2) meng-identifikasi kemelimpahan fitoplankton di laguna Glagah; 3) mempelajari hubungan faktor fisiko-kimia lingkungan dengan kemelimpahan fitoplankton di laguna Glagah. Penelitian dilaksanakan pada tanggal 10 Desember 2012 di laguna Glagah desa Glagah kecamatan Temon Kabupaten Kulonprogo DIY. Pengambilan sampel dilakukan pada 3 stasiun pengamatan untuk mengidentifikasi faktor fisiko-kimia (pH, DO, dan al... 14. Analysis of the stability of events occurred in Laguna Verde; Analisis de estabilidad de eventos ocurridos en Laguna Verde Energy Technology Data Exchange (ETDEWEB) Castillo D, R.; Ortiz V, J. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Calleros M, G. [CFE, Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km. 42.5, Alto Lucero, Veracruz (Mexico) 2005-07-01 The new fuel designs for operation cycles more long have regions of uncertainty bigger that those of the old fuels, and therefore, they can have oscillations of power when an event is presented that causes that the reactor operates to high power and low flow of coolant. During the start up of the reactor there are continued procedures that avoid that oscillations are presented with that which makes sure the stable behavior of the reactor. However, when the reactor is operating to nominal conditions and they are shot or they are transferred to low speed the recirculation pumps, it cannot make sure that the reactor doesn't present oscillations of power when entering to the restricted operation regions. The methods of stability analysis commonly use signs of neutronic noise that require to be stationary, but after a transitory one where they commonly get lost the recirculation pumps the signs they don't have the required characteristics, for what they are used with certain level of uncertainty by the limited validity of the models. In this work the Prony method is used to determine the reactor stability, starting from signs of transitory and it is compared with autoregressive models. Four events are analyzed happened in the Laguna Verde power plant where the reactor was in the area of high power and low flow of coolant, giving satisfactory results. (Author) 15. Future perspectives in neutrino physics: The Laguna-LBNO case CERN Document Server Buizza Avanzini, M 2013-01-01 LAGUNA-LBNO is a Design Study funded by the European Commission to develop the de- sign of a deep underground neutrino observatory; its physics program involves the study of neutrino oscillations at long baselines, the investigation of the Grand Unication of elemen- tary forces and the detection of neutrinos from known and unknown astrophysical sources. Building on the successful format and on the ndings of the previous LAGUNA Design Study, LAGUNA-LBNO is more focused and is specically considering Long Baseline Neutrino Oscil- lations (LBNO) with neutrino beams from CERN. Two sites, Frejus (in France at 130 km) and Pyhasalmi (in Finland at 2300 km), are being considered. Three dierent detector technolo- gies are being studied: Water Cherenkov, Liquid Scintillator and Liquid Argon. Recently the LAGUNA-LBNO consortium has submitted an Expression of Interest for a very long baseline neutrino experiment, selecting as a rst priority the option of a Liquid Argon detector at Pyhasalmi. 16. Cytotoxicity and Apoptotic Activity of Ficus pseudopalma Blanco ... African Journals Online (AJOL) Blanco Leaf Extracts Against Human Prostate Cancer Cell. Lines ... Keywords: Ficus pseudopalma, Cytotoxicity, Apopotic, human prostate PRST2 cancer cell, Lupeol,. Quercetin. ..... apoptosis through Fas-receptor mediated pathway in a ... 17. Project Rio Blanco: site restoration. Final report International Nuclear Information System (INIS) 1978-01-01 Project Rio Blanco was a joint Government-industry experiment using nuclear explosives to stimulate the flow of natural gas from low permeability formations which could not be economically produced through conventional methods. The project consisted of the simultaneous detonation of three nuclear explosives on May 17, 1973, in a 7,000 foot well in northwestern Colorado. Gas production testing and project evaluation continued through June 1976. The site cleanup and restoration planning phase began in December 1975 and was concluded with the issuance of an operational plan, Project Rio Blanco Site Cleanup and Restoration Plan, NVO-173, in May 1976. Actual site restoration activities were conducted during the period from July to November 1976. The activities throughout the restoration period are summarized and the final site status, including the disposition of all project facilities and the status of all project related wells after plug and abandonment and recompletion work are described 18. Blanco sobre blanco : la arquitectura y el cambio cromático Directory of Open Access Journals (Sweden) Jesús Marina Barba 2006-01-01 Full Text Available El color tiene un impacto considerable en la percepción general del paisaje urbano. La luz resalta las superficies, la textura subraya los materiales. Cuando en un paisaje se realiza cualquier intervención, ésta se convierte en atracción visual en relación a su contexto, siendo necesario considerar los factores determinantes de esta nueva relación. El empleo del blanco brillante supone introducir un elemento perceptivo fuerte. Paradójicamente, es el color más agresivo. Los materiales naturales, como la propia naturaleza, tienden a ser complejos en su textura y en sus tonos. El uso generalizado de productos industriales está conduciendo a un empobrecimiento cromático de los paisajes urbanos. El futuro del color blanco pasa por un cambio en su concepción de elemento decorativo hasta convertirlo en fundamento del proyecto, aprovechando sus cualidades de gradación tonal, contraste, expansión espacial y composición de escalas y formas.The colour has a significant impact on the overall perception of an urban environment. Light plays on surfaces, the texture of materials are noticed. Since any object introduced into the environment becomes a visual target in relation to its context, it is necessary to considerer the factors determining that relationship. Brilliant white forms a visual target that attracts the eye. Paradoxically, is the most intrusive colour. Natural materials, like nature itself, tend to be richly textured and subtly coloured. Widely use of industrial products is leading to a chromatic impoverishment on the urbanscape. The future of white is going through a change in its conception as decorative element, until it is turned to project foundation thanks to its qualities of tonal gradation, contrast, spatial expansion and composition of scales and forms. 19. Estudio Limnológico preliminar de la Laguna Hule, Costa Rica Directory of Open Access Journals (Sweden) Elizabeth Ramírez R. 2016-03-01 Full Text Available La Laguna Hule, localizada en la Vertiente Caribe, Costa Rica a 750m sobre el nivel del mar, forma parte del complejo de lagunas volcánicas llamado “Bosque Alegre”. El área de la laguna es de 60.3 ha y su profundidad máxima de 22.5m. La investigación se realizó de abril a setiembre de 1989 determinándose, en cada muestreo la temperatura, el óxido disuelto, el ácido sulfhídrico (H2S, el pH, la alcalinidad y la concentración de iones calcio, magnesio, hierro y manganeso. La laguna presenta un perfil clinógrado de oxígeno; el 60% del volumen total es anóxico con presencia de H2S a partir de los 8m de profundidad. Los valores de pH y alcalinidad indican que las aguas son bicarbonatadas, caracterizándose por un alto contenido de hierro. La curva de temperatura señala una diferencia de hasta 4.3 °C entre la superifcie y el fondo, permitiendo a la laguna permanecer estratificada (hay un epilimnion y un hipolimnion bien definido. 20. Glucuronidation of deoxynivalenol (DON) by different animal species: identification of iso-DON glucuronides and iso-deepoxy-DON glucuronides as novel DON metabolites in pigs, rats, mice, and cows. Science.gov (United States) Schwartz-Zimmermann, Heidi E; Hametner, Christian; Nagl, Veronika; Fiby, Iris; Macheiner, Lukas; Winkler, Janine; Dänicke, Sven; Clark, Erica; Pestka, James J; Berthiller, Franz 2017-12-01 The Fusarium mycotoxin deoxynivalenol (DON) is a frequent contaminant of cereal-based food and feed. Mammals metabolize DON by conjugation to glucuronic acid (GlcAc), the extent and regioselectivity of which is species-dependent. So far, only DON-3-glucuronide (DON-3-GlcAc) and DON-15-GlcAc have been unequivocally identified as mammalian DON glucuronides, and DON-7-GlcAc has been proposed as further DON metabolite. In the present work, qualitative HPLC-MS/MS analysis of urine samples of animals treated with DON (rats: 2 mg/kg bw, single bolus, gavage; mice: 1 mg/kg bw, single i.p. injection; pigs: 74 µg/kg bw, single bolus, gavage; cows: 5.2 mg DON/kg dry mass, oral for 13 weeks) revealed additional DON and deepoxy-DON (DOM) glucuronides. To elucidate their structures, DON and DOM were incubated with human (HLM) and rat liver microsomes (RLM). Besides the expected DON/DOM-3- and 15-GlcAc, minor amounts of four DON- and four DOM glucuronides were formed. Isolation and enzymatic hydrolysis of four of these compounds yielded iso-DON and iso-DOM, the identities of which were eventually confirmed by NMR. Incubation of iso-DON and iso-DOM with RLM and HLM yielded two main glucuronides for each parent compound, which were isolated and identified as iso-DON/DOM-3-GlcAc and iso-DON/DOM-8-GlcAc by NMR. Iso-DON-3-GlcAc, most likely misidentified as DON-7-GlcAc in the literature, proved to be a major DON metabolite in rats and a minor metabolite in pigs. In addition, iso-DON-8-GlcAc turned out to be one of the major DON metabolites in mice. DOM-3-GlcAc was the dominant DON metabolite in urine of cows and an important DON metabolite in rat urine. Iso-DOM-3-GlcAc was detected in urine of DON-treated rats and cows. Finally, DON-8,15-hemiketal-8-glucuronide, a previously described by-product of DON-3-GlcAc production by RLM, was identified in urine of DON-exposed mice and rats. The discovery of several novel DON-derived glucuronides in animal urine requires adaptation of 1. Project Rio Blanco: detonation related activities. Final report International Nuclear Information System (INIS) 1975-01-01 Project Rio Blanco is described in relation to detonation, its history, execution, and results. Topics discussed include generalized site activities, emplacement well, explosive services and operations, operational safety, environmental protection program, seismic effects and damage claims, and add-on programs. (U.S.) 2. Environmental impacts associated with Project Rio Blanco International Nuclear Information System (INIS) Alldredge, A.W.; Whicker, F.W.; Hanson, W.C. Project Rio Blanco, an experiment involving deep underground detonation of three 30-kton nuclear explosives designed to stimulate natural gas flow in geologic formations of low permeability, was conducted in western Colorado on 17 May 1973. Environmental impacts associated with this experiment were divided into three categories: radiation, ground motion, and conventional physical activities. Radiation and ground motion are unique to this type experiment while conventional activities would be associated with any type of resource development. The objective of observations made at Rio Blanco was to qualitatively and, where possible, quantitatively ascertain environmental impacts associated with the project. Observations indicated that ground motion and conventional activities appeared to cause the greatest impacts. Ground motion impacts were most severe within 2.4 km of the emplacement well (EW) and were predominantly associated with steep ravine and stream banks and rocky cliffs. Following the detonation, flow and turbidity had increased in a small stream adjacent to the EW. Animals receiving deleterious impacts were those associated with stream banks, cliffs and burrows. No mortality or injury was observed in any large animals. (U.S.) 3. Inventario nacional de lagunas y represamientos: segunda aproximación OpenAIRE Oficina Nacional de Evaluación de Recursos Naturales 1980-01-01 Contiene el inventario de las lagunas y represamientos existentes en el territorio nacional, destinado a establecer la capacidad física de regulación de los ríos del país. El inventario comprende un listado y descripción sistemática de las lagunas y represamientos en explotación, en estudios o sin uso. 4. 2013 Tres Lagunas Post Fire, 12 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 5. 2013 Tres Lagunas Post Fire, 5 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 6. 2013 Tres Lagunas Post Fire, 30 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 7. 2013 Tres Lagunas Post Fire, 14 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 8. 2013 Tres Lagunas Post Fire, 26 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 9. 2013 Tres Lagunas Post Fire, 3 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 10. 2013 Tres Lagunas Post Fire, 33 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 11. 2013 Tres Lagunas Post Fire, 8 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 12. 2013 Tres Lagunas Post Fire, 18 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 13. 2013 Tres Lagunas Post Fire, 11 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 14. 2013 Tres Lagunas Post Fire, 17 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 15. 2013 Tres Lagunas Post Fire, 27 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 16. 2013 Tres Lagunas Post Fire, 6 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 17. 2013 Tres Lagunas Post Fire, 24 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 18. 2013 Tres Lagunas Post Fire, 4 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 19. 2013 Tres Lagunas Post Fire, 21 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 20. 2013 Tres Lagunas Post Fire, 7 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 1. 2013 Tres Lagunas Post Fire, 32 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 2. 2013 Tres Lagunas Post Fire, 1 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 3. 2013 Tres Lagunas Post Fire, 28 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 4. 2013 Tres Lagunas Post Fire, 9 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 5. 2013 Tres Lagunas Post Fire, 35 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 6. 2013 Tres Lagunas Post Fire, 31 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 7. 2013 Tres Lagunas Post Fire, 34 Data.gov (United States) Earth Data Analysis Center, University of New Mexico — USDA USFS Southwestern Region Contract # AG-8371-C-10-0011 Delivery # AG-8371-D-13-0056 DIGITAL PHOTOGRAPHY ACQUISITION, TRES LAGUNAS FIRE, NEW MEXICO Project... 8. Modification of the colony tower for the Rio Blanco detonation International Nuclear Information System (INIS) Blume, J.A.; Freeman, S.A.; Honda, K.K.; Lee, L.A. 1975-01-01 Supplemental structural bracing was designed and installed for the 180-ft-tall Colony Tower, an experimental oil shale processing retort structure, in anticipation of its lateral response to the Rio Blanco detonation. The tower is a steel structure with both horizontal and vertical diagonal bracing. Data obtained from the earlier Project Rulison detonation indicated that an evaluation study was necessary. Design criteria that would provide an adequate margin of safety were developed based on predicted Rio Blanco ground motion. The evaluation of the unmodified structure showed that several bracing members would be subjected to forces exceeding their yield strength, and some would reach a level at which failure could occur. Further analyses were made with assumed modified bracing members. A final scheme for modified vertical bracing was established and installed. After modification, the response of the tower during the Rio Blanco detonation was measured by instruments on the ground and at various locations on the tower, and no evidence of damage was discovered. The modification of the Colony Tower and the procedures used to determine these modifications show the usefulness of current ground motion and structural response prediction technology for forecasting dynamic behavior of important structures subjected to ground motion from underground nuclear explosions. (auth) 9. First fuel reload in Laguna Verde; Primera recarga de combustible en Laguna Verde Energy Technology Data Exchange (ETDEWEB) Bahena B, D 1992-01-15 A report containing the activities carried out during the first reload of nuclear fuel and major maintenance in the Laguna Verde nuclear reactor is presented. The previous and the specific activities are included. These last are related without including the technical considerations, data or the operation details, because these data were documented inside the registrations of the CFE, the ININ and in personal way. (Author) 10. Analysis of the stability of events occurred in Laguna Verde International Nuclear Information System (INIS) Castillo D, R.; Ortiz V, J.; Calleros M, G. 2005-01-01 The new fuel designs for operation cycles more long have regions of uncertainty bigger that those of the old fuels, and therefore, they can have oscillations of power when an event is presented that causes that the reactor operates to high power and low flow of coolant. During the start up of the reactor there are continued procedures that avoid that oscillations are presented with that which makes sure the stable behavior of the reactor. However, when the reactor is operating to nominal conditions and they are shot or they are transferred to low speed the recirculation pumps, it cannot make sure that the reactor doesn't present oscillations of power when entering to the restricted operation regions. The methods of stability analysis commonly use signs of neutronic noise that require to be stationary, but after a transitory one where they commonly get lost the recirculation pumps the signs they don't have the required characteristics, for what they are used with certain level of uncertainty by the limited validity of the models. In this work the Prony method is used to determine the reactor stability, starting from signs of transitory and it is compared with autoregressive models. Four events are analyzed happened in the Laguna Verde power plant where the reactor was in the area of high power and low flow of coolant, giving satisfactory results. (Author) 11. Validation of SIMULATE-3K for stability analysis of Laguna Verde nuclear plant Energy Technology Data Exchange (ETDEWEB) Castillo, Rogelio, E-mail: [email protected] [Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca s/n, La Marquesa, Ocoyoacac, Estado de México 52750 (Mexico); Alonso, Gustavo, E-mail: [email protected] [Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca s/n, La Marquesa, Ocoyoacac, Estado de México 52750 (Mexico); Instituto Politecnico Nacional, Unidad Profesional Adolfo Lopez Mateos, Ed. 9, Lindavista, D.F. 07300 (Mexico); Ramírez, J. Ramón, E-mail: [email protected] [Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca s/n, La Marquesa, Ocoyoacac, Estado de México 52750 (Mexico) 2013-12-15 Highlights: • Neutronic/thermal hydraulic event in Laguna Verde is modeled. • A good agreement is obtained between SIMULATE-3K results and data plant for frequency and DR. • Other noise analysis techniques are used for the same purpose with good agreement. • Validation of SIMULATE-3K for stability analysis of Laguna Verde is confirmed - Abstract: Boiling Water Reactors are two phase flow systems which are susceptible to different types of flow instabilities. Among these are the coupled neutronic/thermal-hydraulic instabilities, these may compromise established fuel safety limits. These instabilities are characterized by periodic core-power and hydraulic oscillations. SIMULATE-3K code has been tested for stability analysis for several benchmarks, however to qualify the SIMULATE-3K code for a particular power plant a specific reactor plant analysis must be done. In this paper, the plant model of Laguna Verde Nuclear Power Plant is built and SIMULATE-3K is tested against the 1995 coupled neutronic/thermal-hydraulic instability event of Laguna Verde. Results obtained show the adequacy of this code to specific Laguna Verde power plant stability analysis. 12. Some environmental impacts associated with project Rio Blanco International Nuclear Information System (INIS) Alldredge, A.W.; Whicker, F.W.; Hanson, W.C. 1976-01-01 Project Rio Blanco, an experiment involving deep underground detonation of three 30-kiloton nuclear explosives designed to stimulate natural gas flow in geologic formations of low permeability, was conducted in western Colorado on 17 May 1973. Environmental impacts associated with this experiment were divided into three categories: radiation, ground motion, and conventional physical activities. The objective of observations made at Rio Blanco was to qualitatively and, where possible, quantitatively ascertain environmental impacts associated with the project. Observations indicated that ground motion and conventional activities appeared to cause the greatest impacts. Ground motion impacts were most severe within 2.4 km of the emplacement well (EW) and were predominantly associated with steep ravine and stream banks and rocky cliffs. Following the detonation, flow and turbidity had increased in a small stream adjacent to the EW. Animals receiving deleterious impacts were those associated with stream banks, cliffs and burrows. No mortality or injury was observed in any large animals. Based on overall results it appears important to give adequate attention to environmental effects resulting from nuclear fracturing experiments 13. Condiciones sedimentológicas de la laguna la restinga, isla de margarita, venezuela OpenAIRE C, Julio; Salazar, L; A, Jesús; C, Rosas; C, Julio; Rodríguez, R 2003-01-01 Resumen La laguna La Restinga, en el sureste del Mar Caribe, es una laguna costera que comprende pequeñas lagunas rodeadas de manglares, conformando el sistema lagunar más importante de la Isla de Margarita. Se comunica con el mar, al sur, a través de una boca de 800m de largo, 80-100m de ancho y profundidad promedio de 6m. Está separada del mar, al norte, por un istmo o restinga de 23,5km, y sus drenajes naturales se evidencian solamente en la época de lluvia. Se estudiaron algunos aspectos ... 14. Design Study for a Future Laguna-LBNO Long-Baseline Neutrino Facility at CERN CERN Document Server Alabau-Gonzalvo, J; Antoniou, F; Benedikt, M; Calviani, M; Efthymiopoulos, I; Ferrari, A; Garoby, R; Gerigk, F; Gilardoni, S; Goddard, B; Kosmicki, A; Lazaridis, C; Osborne, J; Papaphillippou, Y; Parfenova, A; Shaposhnikova, E; Steerenberg, R; Velten, P; Vincke, H 2013-01-01 The Large Apparatus studying Grand Unification and Neutrino Astrophysics (LAGUNA) study [1] investigated seven pre-selected underground sites in Europe (Finland, France, Italy, Poland, Romania, Spain and UK), capable of housing large volume detectors for terrestrial, accelerator generated and astrophysical neutrino research. The study was focused on geo-technical assessment of the sites, concluding that no show-stoppers exist for the construction of the required large underground caverns in the chosen sites. The LAGUNA-LBNO FP7/EC-funded design study extends the LAGUNA study in two key aspects: the detailed engineering of detector construction and operation, and the study of a long-baseline neutrino beam from CERN, and possibly other accelerator centres in Europe. Based on the findings of the LAGUNA study, the Pyh¨asalmi mine in Finland is chosen as prime site for the far detector location. The mine offers the deepest underground location in Europe (-1400 m) and a baseline of 2’300 km from CERN (Fig. 1). ... 15. Nevus blanco esponjoso familiar Directory of Open Access Journals (Sweden) Mônica Andrade Lotufo 2010-06-01 Full Text Available El nevus blanco esponjoso (NBE es una rara condición autosómica dominante, caracterizada por placas blancas bilaterales en la mucosa, de aspecto esponjoso, blandas a la palpación y que pueden escamarse. Los tratamientos son paliativos; y el uso de antibióticos, en especial la tetraciclina, ha demostrando buenos resultados en su control. Este trabajo presenta tres casos clínicos de una familia afectada por NBE, donde se discuten los posibles diagnósticos diferenciales y conductas terapéuticas indicadas. Un paciente masculino de 52 años de edad acudió a la clínica aquejado de lesiones blancas bilaterales. El paciente notó las lesiones 30 años antes, sin lograr un diagnóstico final de las mismas. Después de la anamnesis y del examen clínico fue realizada una biopsia incisional. La reunión de los datos clínicos e histopatológicos llevó al diagnóstico de NBE. Se le solicitó al paciente que indagase entre sus familiares con respecto a lesiones semejantes. Se detectó que el hijo de 19 años y la hija de 25 eran portadores de placas blancas en la mucosa yugal. Como no había afectación estética, se optó por no intervenir en las lesiones. El nevus blanco esponjoso es una lesión genética que debe ser diferenciada de otras patologías localizadas y sistémicas importantes, que tienen repercusiones serias para el individuo. Como no hay un tratamiento curativo para el NBE, el papel del cirujano dentista es diagnosticar esta lesión, aclarar al paciente sobre la naturaleza benigna y autolimitante del NBE y si fuera necesario desde el punto de vista estético, aplicar diferentes modalidades terapéuticas. 16. Design optimization of the Laguna Verde nuclear power station fuel recharge; Optimacion del diseno de recargas de combustible para la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Cortes Campos, Carlos Cristobal [Instituto de Investigaciones Electricas, Cuernavaca (Mexico); Montes Tadeo, Jose Luis [Instituto Nacional de Investigaciones Nucleares (ININ), Salazar (Mexico) 1991-12-31 It is described, in general terms, the procedure that is followed to accomplish the optimization of the recharge design, and an example is shown where this procedure was applied for the analysis of the type BWR reactor of Unit No. 1 of the Laguna Verde Nuclear Power Station. [Espanol] Se describe en terminos generales el procedimiento que se sigue para realizar la optimacion del diseno de recargas, y se muestra un ejemplo en el que se utilizo dicho procedimiento para el analisis del reactor tipo BWR de la unidad 1, de la Central Laguna Verde (CLV). 17. Design optimization of the Laguna Verde nuclear power station fuel recharge; Optimacion del diseno de recargas de combustible para la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Cortes Campos, Carlos Cristobal [Instituto de Investigaciones Electricas, Cuernavaca (Mexico); Montes Tadeo, Jose Luis [Instituto Nacional de Investigaciones Nucleares (ININ), Salazar (Mexico) 1992-12-31 It is described, in general terms, the procedure that is followed to accomplish the optimization of the recharge design, and an example is shown where this procedure was applied for the analysis of the type BWR reactor of Unit No. 1 of the Laguna Verde Nuclear Power Station. [Espanol] Se describe en terminos generales el procedimiento que se sigue para realizar la optimacion del diseno de recargas, y se muestra un ejemplo en el que se utilizo dicho procedimiento para el analisis del reactor tipo BWR de la unidad 1, de la Central Laguna Verde (CLV). 18. Laguna Verde: the nuclear debate in Mexico International Nuclear Information System (INIS) Weinberg, Bill. 1987-01-01 Mexico in planning to start up its first nuclear power station at Laguna Verde in the state of Veracruz (1988). The history of the plant is traced; it should have been finished by 1974. Both the fuel and the technology have been imported from the United States for Laguna Verde. The design, a Mark II Boiling Water Reactor, is controversial and there are doubts as to its safety. Opposition to the plant on safety and environmental grounds has grown. In April 1987 a 'Chernobyl anniversary' demonstration had 10,000 protesters and opponents of the plant are becoming more militant. The main opposition is from environmental and 'Green' groups but also includes intellectuals. However, politically, Mexico would find it embarrassing to cancel the plant and also it wants to be seen as a 'First World' rather than a 'Third World' country. (U.K.) 19. Botanical ecology and conservation of the Laguna de la Herrera (Sabana de Bogotá, Colombia Botanical ecology and conservation of the Laguna de la Herrera (Sabana de Bogotá, Colombia Directory of Open Access Journals (Sweden) Wijninga V. M. 1989-09-01 Full Text Available The acuatic, helophytic and pleustophytic vegetation of the Laguna de La Herrera, on the southwestern border of the high plain of Bogotá at 2550 m was studied following the Zurich- Montpellier approach. The communities recognized were: terrestrial community of Phytolacca bogotensis; helophytic communities of scirpus californicus and Typha angustifolia ; scirpus californicus ; Polygonum punctatum ; Rumex obtusifolius with Polygonum punctatum; Bidens laevis ; Hydrocotyle ranunculoides. Pleustophytic communities of Limnobium laevigatum; Azolla filiculoides with Lemna cf. gibba and Eichornia crassipes. The structure, floristic composition and ecological aspects were also considered. Several recommendations about conservation of the Laguna are given. Se estudió la vegetación alrededor de la Laguna de La Herrera, una laguna andina a 2550 m. Se diferenciaron una comunidad de Phytolacca bogotensis (1: comunidades helofíticas dominadas por: Scirpus californicus y Typha angustifolia (2; Scirpus californicus (3; Polygonum punctatum (4; Rumex obtusifolius y Polygonum punctatum (5; Bidens laevis (6; Hydrocotyle ranunculoides (7; comunidades pleustofíticas con: Limnobium laevigatum; (8; Azolla filiculoides y Lemna cf. gibba (9 y Eichhornia crassipes (10. Se registraron la estructura, composición florística, los rasgos ecológicos y la distribución de las comunidades y se comparó con la conductividad eléctrica y la calidad del agua. Finalmente, se hacen recomendaciones para la conservación de la laguna y la vegetación acuática. 20. First fuel reload in Laguna Verde International Nuclear Information System (INIS) Bahena B, D. 1992-01-01 A report containing the activities carried out during the first reload of nuclear fuel and major maintenance in the Laguna Verde nuclear reactor is presented. The previous and the specific activities are included. These last are related without including the technical considerations, data or the operation details, because these data were documented inside the registrations of the CFE, the ININ and in personal way. (Author) 1. Aves acuáticas de la laguna de Acuitlapilco, Tlaxcala, México Directory of Open Access Journals (Sweden) Juanita Fonseca 2012-07-01 Full Text Available Estudiamos la abundancia y distribución estacional de las aves acuáticas en la laguna de Acuitlapilco, Tlaxcala, México. De febrero de 2011 a enero de 2012, realizamos censos en puntos de conteo para el registro de las especies. Registramos un total de 36 especies de aves acuáticas con una abundancia total acumulada de 48,794 individuos. Doce de las especies registradas fueron residentes, 10 migratorias y 14 fueron especies transitorias o de registro accidental. Observamos que la mayor riqueza de especies y abundancia de aves fueron en invierno, cuando la mayoría de las especies migratorias llegaron a la laguna. Nuestros resultados muestran que esta área es importante para especies de aves acuáticas tanto residentes como migratorias, y refleja la necesidad de un mayor número de estudios sobre el papel de las lagunas continentales como reservorios de biodiversidad. 2. Laguna Verde nuclear power plant: an experience to consider in advanced BWR design International Nuclear Information System (INIS) Fuentes Marquez, L. 2001-01-01 Laguna Verde is a BWR 5 containment Mark II. Designed by GE, two external re-circulation loops, each of them having two speed re-circulation pump and a flow control valve to define the drive flow and consequently the total core flow an power control by total core flow. Laguna Verde Design and operational experience has shown some insights to be considering in design for advanced BRW reactors in order to improve the potential of nuclear power plants. NSSS and Balance of plant design, codes used to perform nuclear core design, margins derived from engineering judgment, at the time Laguna Verde designed and constructed had conducted to have a plant with an operational license, generating with a very good performance and availability. Nevertheless, some design characteristics and operational experience have shown that potential improvements or areas of opportunity shall be focused in the advanced BWR design. Computer codes used to design the nuclear core have been evolved relatively fast. The computers are faster and powerful than those used during the design process, also instrumentation and control are becoming part of this amazing technical evolution in the industry. The Laguna Verde experience is the subject to share in this paper. (author) 3. quebracho-blanco Schlecht Directory of Open Access Journals (Sweden) E. O. Sanabria 2007-01-01 Full Text Available La especie Aspidosperma quebracho-blanco Schlecht es la más abundante del Parque Chaqueño y no es utilizada en la producción de bienes de alto valor agregado debido a la inestabilidad dimensional de su madera. Una de las maneras de mejorar la estabilidad dimensional es el engrosado de la pared celular con polietilenglicol (PEG. El objetivo de este trabajo fue determinar el efecto del PEG de peso molecular 300 y 600 en la estabilidad dimensional, utilizando como parámetro de control el coeficiente de retractabilidad de la madera citada. Las muestras se impregnaron en una Planta Piloto con PEG, a través del proceso Bethell, según Norma IRAM Núm. 9511. Posteriormente se secaron hasta un contenido de humedad (CH del 10 %. Los mejores resultados se lograron impregnando la madera con PEG 600, a una concentración del 50 % en solución acuosa, a una presión de 12 kg·cm-2 durante 120 minutos, lo que permitió disminuir el coeficiente de retractabilidad de esta madera en 58.2 %. 4. IDENTIFICATION OF THE LITHIUM DEPLETION BOUNDARY AND AGE OF THE SOUTHERN OPEN CLUSTER BLANCO 1 International Nuclear Information System (INIS) Cargile, P. A.; James, D. J.; Jeffries, R. D. 2010-01-01 We present results from a spectroscopic study of the very low mass members of the Southern open cluster Blanco 1 using the Gemini-N telescope. We obtained intermediate resolution (R ∼ 4400) GMOS spectra for 15 cluster candidate members with I ∼ 14-20 mag, and employed a series of membership criteria-proximity to the cluster's sequence in an I/I - K s color-magnitude diagram (CMD), kinematics agreeing with the cluster systemic motion, magnetic activity as a youth indicator-to classify 10 of these objects as probable cluster members. For these objects, we searched for the presence of the Li I 6708 A feature to identify the lithium depletion boundary (LDB) in Blanco 1. The I/I - K s CMD shows a clear mass segregation in the Li distribution along the cluster sequence; namely, all higher mass stars are found to be Li poor, while lower mass stars are found to be Li rich. The division between Li-poor and Li-rich (i.e., the LDB) in Blanco 1 is found at I = 18.78 ± 0.24 and I - K s = 3.05 ± 0.10. Using current pre-main-sequence evolutionary models, we determine an LDB age of 132 ± 24 Myr. Comparing our derived LDB age to upper-main-sequence isochrone ages for Blanco 1, as well as for other open clusters with identified LDBs, we find good chronometric consistency when using stellar evolution models that incorporate a moderate degree of convective core overshoot. 5. Acumulación/eliminación de oxitetraciclina en el camarón blanco, lv y su residualidad en dietas artificiales OpenAIRE Montoya, Nelson; Reyes, Eduardo 2002-01-01 Acumulación/eliminación de oxitetraciclina en el camarón blanco, LV y su residualidad en dietas artificiales Acumulación/eliminación de oxitetraciclina en el camarón blanco, LV y su residualidad en dietas artificiales 6. Rio Blanco gas composition: preproduction testing of the RBE-01 wellhead International Nuclear Information System (INIS) Smith, C.F.; Fontanilla, J.E. 1976-01-01 The chemical composition and radionuclide concentration of Rio Blanco gas samples collected prior to the production testing of the RBE-01 well and analyzed at LLL are presented. The analytical procedures and their uncertainties are briefly summarized. Information that associates the analytical data with the field operations is included 7. DISTRIBUSI HUTAN BAKAU DI LAGUNA PANTAI SELATAN YOGYAKARTA (Mangrove Distribution at the Lagoons in the Southern Coast of Yogyakarta Directory of Open Access Journals (Sweden) Tjut Sugandawaty Djohan 2007-03-01 Full Text Available ABSTRAK Kehadiran sisa hutan bakau di laguna Bogowonto, pantai selatan Yogyakarta menunjukkan bahwa pada masa lalu laguna tersebut didominasi oleh hutan bakau, sehingga penelitian ini bertujuan mempelajari kehadiran vegetasi bakau di laguna-laguna dan muara sungai di pantai selatan tersebut. Ada empat laguna di pantai Selatan Yogyakarta, laguna Bogowonto, Serang, Progo, Opak, dan satu muara sungai, Kali Baron. Laguna tersebut merupakan laguna internitten, artinya pada musim kemarau, mulut sungainya tertutup gumuk pasir dan laguna didominasi oleh perairan tawar dan merupakan ekosistem tergenang. Sebaliknya di musim hujan mulut sungai terbuka, laguna bersifat sebagai ekosistem pasang surut. Data vegetasi dicuplik dengan menggunakan kuadrat plot berukuran 10m x 20m dengan ulangan dua kali. Kuadrat plot ditempatkan pada pusat distribusi mangrovenya, yang dipilih mulai dari rawa burit ke arah muara sungai. Tekstur tanah, hara tanah, salinitas air dan hara air juga dikaji. Kehadiran hutan bakau di laguna dibatasi oleh tekstur tanah. Tekstur pasir, 60-99 %, mendominasi laguna Serang, Progo, Opak dan muara kali Baron. Komunitas bakau hanya ditemukan di laguna Bogowonto, yang tersusun atas 5 jenis bakau, Sonneratia alba, Nypa fruticans, Acanthus ilicifolius, Acrosticum sp., dan Derris heterophylla, dan dua jenis spesies peralihan, Pandanus sp. dan Cynodon dactylon. Pola distribusi komunitasnya mengelompok (clump, mempunyai tipe riverine mangrove,dan tidak membentuk zonasi. Sonneratia hadir mulai dari muara sungai sampai di rawa burit. Ketika air surut salinitas berkisar antara 0-6,5 %. Nypa hanya ditemukan satu kelompok di kaki gumuk. Distribusi Sonneratia tidak ditentukan oleh tinggi genangan, akan tetapi tinggi pneumatophor mengikuti pola tinggi genangan air. Di laguna Bogowonto, spesies bakau tidak mempunyai zonasi dan beradaptasi pada sistem ekologinya. ABSTRACT The presence of mangrove remnant at the lagoon of Bogowonto River in the southern 8. Aves ocasionales en la Sabana de Bogotá y las Lagunas de Fúquene y de Tota Directory of Open Access Journals (Sweden) Borrero José Ignacio 1947-12-01 Full Text Available En números anteriores de esta misma revista publiqué algunas listas preliminares anotando la presencia ocasional de ciertas aves en la Sabana de Bogotá y la Laguna de Fúquene. A continuación hago mención de otras especies que he encontrado en las mismas localidades o también en la Laguna de Tota, Boyacá, a 3015 metros de altitud. Por considerarlo de importancia desde el punto de vista de la distribución geográfica, doy también datos referentes a la presencia de un ave migratoria norteamericana (Colymbus niqricollis californicus en la Laguna de Tota. 9. Stability of DON and DON-3-glucoside during baking as affected by the presence of food additives. Science.gov (United States) Vidal, Arnau; Sanchis, Vicente; Ramos, Antonio J; Marín, Sonia 2018-03-01 The mycotoxin deoxynivalenol (DON) is one of the most common mycotoxins of cereals worldwide, and its occurrence has been widely reported in raw wheat. The free mycotoxin form is not the only route of exposure; modified forms can also be present in cereal products. Deoxynivalenol-3-glucoside (DON-3-glucoside) is a common DON plant conjugate. The mycotoxin concentration could be affected by food processing; here, we studied the stability of DON and DON-3-glucoside during baking of small doughs made from white wheat flour and other ingredients. A range of common food additives and ingredients were added to assess possible interference: ascorbic acid (E300), citric acid (E330), sorbic acid (E200), calcium propionate (E282), lecithin (E322), diacetyltartaric acid esters of fatty acid mono- and diglycerides (E472a), calcium phosphate (E341), disodium diphosphate (E450i), xanthan gum (E415), polydextrose (E1200), sorbitol (E420i), sodium bicarbonate (E500i), wheat gluten and malt flour. The DON content was reduced by 40%, and the DON-3-glucoside concentration increased by >100%, after baking for 20 min at 180°C. This confirmed that DON and DON-3-glucoside concentrations can vary during heating, and DON-3-glucoside could even increase after baking. However, DON and DON-3-glucoside are not affected significantly by the presence of the food additives tested. 10. The technology transfer and the Laguna Verde power plants International Nuclear Information System (INIS) Garza, R.F. de La 1991-01-01 The process of technology transfer to the construction of Laguna Verde Nuclear Power Plants, Mexico, is described. The options and the efforts for absorbing the technology of Nuclear Power Plant design and construction by the mexican engineers are emphasized. (author) 11. Transient analysis for Laguna Verde nuclear power plant International Nuclear Information System (INIS) Ramos Pablos, J.C. et.al. 1991-01-01 Relationship between transients analysis and safety of Laguna Verde nuclear power plant is described a general panorama of safety thermal limits of a nuclear station, as well as transients classification and events simulation codes are exposed. Activities of a group of transients analysis of electrical research institute are also mentioned (Author) 12. TRATAMIENTO DE EFLUENTES PISCÍCOLAS (TILAPIA ROJA EN LAGUNAS CON Azolla pinnata Directory of Open Access Journals (Sweden) GUILLERMO CHAUX F 2013-12-01 Full Text Available Los sistemas con plantas acuáticas flotantes son una alternativa económicamente sostenible para el tratamiento de efluentes piscícolas. Se evaluó a escala piloto el desempeñ,o de un sistema de lagunas con Azolla pinnata en serie para el tratamiento de efluentes de cría de tilapia roja durante el proceso de levante y engorde. El sistema construido en la piscícola La Yunga (Popayán, Colombia consistió en dos líneas de cinco lagunas en serie; la primera con A. pinnata y la segunda sin la planta acuática; cada laguna se operó con un tiempo de detención de un día. La evaluación se realizó en época seca. La producción de Azolla fresca osciló entre 42 y 87 g/m2.d y el contenido de proteína entre 18,5% y 20,4%. Las eficiencias de remoción obtenidas en las líneas (con Azolla, sin Azolla fueron respectivamente: 56% y 46% DBO5; 49% y 26% DQO; 56% y 33% SST; 28% y 36% N-NTK; -108% y 23% N-NH4+; 64% y 34% fósforo total, mostrando superioridad del sistema con Azolla. Con solo tres lagunas en serie plantadas con A. pinnata se alcanzan las eficiencias máximas obtenidas en la remoción de DBO5, DQO, SST y fósforo total. 13. BLANCO MOUNTAIN AND BLACK CANYON ROADLESS AREAS, CALIFORNIA. Science.gov (United States) Diggles, Michael F.; Rains, Richard L. 1984-01-01 The mineral survey of the Blanco Mountain and Black Canyon Roadless Areas, California indicated that areas of probable and substantiated mineral-resource potential exist only in the Black Canyon Roadless Area. Gold with moderate amounts of lead, silver, zinc, and tungsten, occurs in vein deposits and in tactite. The nature of the geological terrain indicates little likelihood for the occurrence of energy resources in the roadless areas. Detailed geologic mapping might better define the extent of gold mineralization. Detailed stream-sediment sampling and analysis of heavy-mineral concentrations could better define tungsten resource potential. 14. “Is that right?” – Don Favareau, Don Corleone & the semiotics of friendship DEFF Research Database (Denmark) Emmeche, Claus 2017-01-01 A chapter commenting specifically on John Poinsot's "Tractatus de Signis", John Deely's interpretation of Poinsot's mentioning of "friendship" as an example of a triadic relation, Don Favareau's contribution to the biosemiotic community, and Don Corleone as a symbol of a different kind of "friend......A chapter commenting specifically on John Poinsot's "Tractatus de Signis", John Deely's interpretation of Poinsot's mentioning of "friendship" as an example of a triadic relation, Don Favareau's contribution to the biosemiotic community, and Don Corleone as a symbol of a different kind...... of "friendship", and generally on the philosophy of friendship.... 15. Dynamic analysis of the condensate and of the feed water in the Laguna Verde nuclear power station; Analisis dinamico del sistema de condensado y agua de alimentacion de la nucleoelectrica de Laguna Verde Energy Technology Data Exchange (ETDEWEB) Macedo Muth, Javier; Sandoval Pena, Ramon [Instituto de Investigaciones Electricas, Cuernavaca (Mexico) 1988-12-31 This article shows a non-lineal mathematical model for the condensate, and feed water systems and for feed water heater drains at the Laguna Verde Nuclear Power Station for its simulation in real time. The model allows the calculation of flows and pressures in all the piping system and equipment that integrate the systems. It was obtained by using the force unbalance in the fluid concept and is capable of reproducing its dynamic behavior through variations induced by the different operation modes and more common failures. The final model objective is to form part of the Laguna Verde simulator that will be used for operator training of this Nuclear Power Plant. [Espanol] En este articulo se muestra un modelo matematico no lineal de los sistemas de condensado, agua de alimentacion y drenes de calentadores de la central nuclear de Laguna Verde para su simulacion en tiempo real. El modelo permite calcular los flujos y las presiones en toda la red de tuberias y equipos que integran los sistemas. Se obtuvo utilizando el concepto de desbalance de fuerzas en el fluido, y es capaz de reproducir su comportamiento dinamico ante variaciones inducidas por los diversos modos de operacion y fallas mas comunes. El objetivo final del modelo es formar parte del simulador de Laguna Verde que se empleara para el adiestramiento de los operadores de dicha central nuclear. 16. Contaminación producida por piscicultura intensiva en lagunas andinas de Junín, Perú Directory of Open Access Journals (Sweden) Mauro Mariano 2011-05-01 Full Text Available Se reportan los cambios producidos por el cultivo intensivo de la trucha Oncorhynchus mykiss en siete lagunas andinas. Las observaciones se realizaron en el año 1996, y entre el 2002 - 2007 y permitieron observar el proceso de deterioro de las lagunas, caracterizado por el incremento en las concentraciones de fosforo total y la disminución del oxigeno disuelto y la transparencia. La comunidad béntica fue evaluada en las siete lagunas en el 2007, resultando el número de especies y los índices de diversidad bajos (H'<1,26; <8 spp.. La abundancia varió entre 7 y 35 ind./0,04m2. La materia orgánica y carbonatos en fondo fueron altos (30,22 - 42,45%. 17. Project Rio Blanco definition plan. Additional formation evaluation and production testing International Nuclear Information System (INIS) 1975-09-01 Since the multiple Rio Blanco detonation three reentry wells have been drilled for test purposes: RB-E-01 (Emplacement Well); RB-AR-2 (Alternate Reentry Well); and RB-U-4 (Formation Evaluation Well). Additional testing in all these wells is now required to resolve some remaining technical questions. A plan describing the procedures, methods, responsibilities, and scheduling of the field operations is presented 18. Botanical ecology and conservation of the laguna de la herrera (sabana de bogotá, colombia) OpenAIRE Wijninga, V. M.; Rangel, Orlando; Cleef, A. M. 2012-01-01 Se estudió la vegetación alrededor de la Laguna de La Herrera, una laguna andina a 2550 m. Se diferenciaron una comunidad de Phytolacca bogotensis (1): comunidades helofíticas dominadas por: Scirpus californicus y Typha angustifolia (2); Scirpus californicus (3); Polygonum punctatum (4); Rumex obtusifolius y Polygonum punctatum (5); Bidens laevis (6); Hydrocotyle ranunculoides (7); comunidades pleustofíticas con: Limnobium laevigatum; (8); Azolla filiculoides y Lemna cf. gibba (9) y Eichhorni... 19. Morir y matar amando: Amor de don Perlimplín con Belisa en su jardín Directory of Open Access Journals (Sweden) Peral Vega, Emilio 2004-04-01 Full Text Available «Morir y matar amando: Amor de don Perlimplín con Belisa en su Jardín» apuesta por una de las obras dramáticas lorquianas no sólo de menor presencia escénica sino también de menor bibliografía secundaria en torno a ella. Y lo hace analizando la intrincada red de influencias -desde la commedia dell'arte italiana, pasando por el teatro breve del Siglo de Oro español, para llegar al simbolismo francés- que convierte a su personaje, Perlimplín, en un ente dramático esencial, capaz de sacudirse una tradición que había hecho de sus congéneres cornudos -recordemos el Cañizares cervantino que tanto se le asemeja en un primer estadio de la pieza- unos peleles al servicio de una comicidad de guante blanco,… 20. Internal event analysis of Laguna Verde Unit 1 Nuclear Power Plant. System Analysis International Nuclear Information System (INIS) Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R. 1993-01-01 The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the I nternal Event Analysis of Laguna Verde Unit 1 Nuclear Power Plant , CNSNS-TR-004, in five volumes. The reports are organized as follows: CNSNS-TR-004 Volume 1: Introduction and Methodology. CNSNS-TR-004 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR-004 Volume 3: System Analysis. CNSNS-TR-004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR-004 Volume 5: Appendices A, B and C. This volume presents the results of the system analysis for the Laguna Verde Unit 1 Nuclear Power Plant. The system analysis involved the development of logical models for all the systems included in the accident sequence event tree headings, and for all the support systems required to operate the front line systems. For the Internal Event analysis for Laguna Verde, 16 front line systems and 5 support systems were included. Detailed fault trees were developed for most of the important systems. Simplified fault trees focusing on major faults were constructed for those systems that can be adequately represent,ed using this kind of modeling. For those systems where fault tree models were not constructed, actual data were used to represent the dominant failures of the systems. The main failures included in the fault trees are hardware failures, test and maintenance unavailabilities, common cause failures, and human errors. The SETS and TEMAC codes were used to perform the qualitative and quantitative fault tree analyses. (Author) 1. Proposal for implementation of alternative source term in the nuclear power plant of Laguna Verde; Propuesta de implementacion del termino fuente alternativo en la central nuclear Laguna Verde Energy Technology Data Exchange (ETDEWEB) Bazan L, A.; Lopez L, M.; Vargas A, A.; Cardenas J, J. B. [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Km. 7.5 Carretera Veracruz-Medellin, Dos Bocas, Veracruz (Mexico)], e-mail: [email protected] 2009-10-15 In 2010 the nuclear power plant of Laguna Verde will implement the extended power upbeat in both units of the plant. Agree with methodology of NEDC-33004P-A, (constant pressure power up rate), and the source term of core, for accidents evaluations, were increased in proportion to the ratio of power level. This means that for the case of a design basis accident of loss of coolant an increase of power of 15% originated an increase of 15% in dose to main control room. Using the method of NEDC-33004P-A to extended power upbeat conditions was determined that the dose value to main control room is very near to regulatory limit established by SRP 6.4. By the above and in order to recover the margin, the nuclear power plant of Laguna Verde will calculate an alternative source term following the criteria established in RG 1.183 (alternative radiological source term for evaluating DBA at nuclear power reactor). This approach also have a more realistic dose value using the criterion of 10-CFR-50.67, in addition is predicted to get the benefit of additional operational flexibilities. This paper present the proposal of implementing the alternative source term in Laguna Verde. (Author) 2. Internal event analysis of Laguna Verde Unit 1 Nuclear Power Plant. System Analysis; Analisis de Eventos Internos para la Unidad 1 de la Central Nucleoelectrica de Laguna Verde. Analisis de sistemas Energy Technology Data Exchange (ETDEWEB) Huerta B, A; Aguilar T, O; Nunez C, A; Lopez M, R [Comision Nacional de Seguridad Nuclear y Salvaguardias, 03000 Mexico D.F. (Mexico) 1993-07-01 The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the {sup I}nternal Event Analysis of Laguna Verde Unit 1 Nuclear Power Plant{sup ,} CNSNS-TR-004, in five volumes. The reports are organized as follows: CNSNS-TR-004 Volume 1: Introduction and Methodology. CNSNS-TR-004 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR-004 Volume 3: System Analysis. CNSNS-TR-004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR-004 Volume 5: Appendices A, B and C. This volume presents the results of the system analysis for the Laguna Verde Unit 1 Nuclear Power Plant. The system analysis involved the development of logical models for all the systems included in the accident sequence event tree headings, and for all the support systems required to operate the front line systems. For the Internal Event analysis for Laguna Verde, 16 front line systems and 5 support systems were included. Detailed fault trees were developed for most of the important systems. Simplified fault trees focusing on major faults were constructed for those systems that can be adequately represent,ed using this kind of modeling. For those systems where fault tree models were not constructed, actual data were used to represent the dominant failures of the systems. The main failures included in the fault trees are hardware failures, test and maintenance unavailabilities, common cause failures, and human errors. The SETS and TEMAC codes were used to perform the qualitative and quantitative fault tree analyses. (Author) 3. Desarrollo, trabajo y género: El caso de la Laguna de Yahuarcocha Directory of Open Access Journals (Sweden) Diosey Ramon Lugo-Morin 2015-06-01 Full Text Available El presente estudio propone valorar el papel de la mujer rural de los territorios aledaños a la Laguna de Yahuarcocha. Escenario propicio para generar una dinámica económica en las comunidades de San Miguel de Yahuarcocha y Priorato donde las mujeres tienen un rol de importancia estratégica. Se concluye que la participación de las mujeres en la dinámica económica entorno a la Laguna de Yahuarcocha es determinante para el desarrollo del territorio sobre todo en el ámbito turístico. 4. Don\\'t Ask, Don\\'t Tell: Ethical Issues Concerning Learning and ... African Journals Online (AJOL) Informed consent procedures and requirements must be clearly established and communicated. The learning and proficiency practices should be restricted to the staff that can truly benefit from the experience. The practice of 'don't ask, don't tell' is not an option. South African Journal of Family Practice Vol. 50 (4) 2008: pp. 5. 2015 Long-Term Hydrologic Monitoring Program Sampling and Analysis Results at Rio Blanco, Colorado Energy Technology Data Exchange (ETDEWEB) Findlay, Rick [Nararro Research and Engineering, Oak Ridge, TN (United States); Kautsky, Mark [US Department of Energy, Washington, DC (United States). Office of Legacy Management 2015-12-01 The U.S. Department of Energy (DOE) Office of Legacy Management conducted annual sampling at the Rio Blanco, Colorado, Site for the Long-Term Hydrologic Monitoring Program (LTHMP) on May 20–21, 2015. This report documents the analytical results of the Rio Blanco annual monitoring event, the trip report, and the data validation package. The groundwater and surface water monitoring samples were shipped to the GEL Group Inc. laboratories for conventional analysis of tritium and analysis of gamma-emitting radionuclides by high-resolution gamma spectrometry. A subset of water samples collected from wells near the Rio Blanco site was also sent to GEL Group Inc. for enriched tritium analysis. All requested analyses were successfully completed. Samples were collected from a total of four onsite wells, including two that are privately owned. Samples were also collected from two additional private wells at nearby locations and from nine surface water locations. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry, and they were analyzed for tritium using the conventional method with a detection limit on the order of 400 picocuries per liter (pCi/L). Four locations (one well and three surface locations) were analyzed using the enriched tritium method, which has a detection limit on the order of 3 pCi/L. The enriched locations included the well at the Brennan Windmill and surface locations at CER-1, CER-4, and Fawn Creek 500 feet upstream. 6. Modernization of the turbo in the Laguna Verde Nuclear Power Plant; Modernizacion del turbogrupo en la Central Nuclear de Laguna Verde Energy Technology Data Exchange (ETDEWEB) Liebana, B.; Merino, A.; Cobos, A.; Gonzalez, J. J. 2010-07-01 The power increase of the Laguna Verde Nuclear Power Plant is a project for the rehabilitation and modernization of the turbo and associated equipment to get an increase of its power and of its service life. The project scope includes the design, the engineering, the equipment supply, the installation, the testing and the commissioning. This paper describes the first phase of the project. 7. The rise of repeal: policy entrepreneurship and Don't Ask, Don't Tell. Science.gov (United States) Neff, Christopher L; Edgell, Luke R 2013-01-01 We report on policy entrepreneurship by Servicemembers Legal Defense Network (SLDN) and how its legislative strategies used mini-windows of opportunity to shift Capitol Hill perspectives of Don't Ask, Don't Tell (DADT) from political plutonium to an emerging issue requiring a second look. Four phases in the legislative history of DADT are identified: radioactive, contested, emerging, and viable. In all, this article argues that SLDN's entrepreneurship focused on contesting congressional sensibilities to wait or defer on repeal, maintained that every discharge was damaging and transitioned toward a post-repeal mind set. Finally, we illustrate the importance of these transitions by comparing SLDN's 2004 estimated vote count for the introduction of the Military Readiness Enhancement Act with the final 2010 voting results on the Don't Ask, Don't Tell Repeal Act. 8. Guidelines: the do's, don'ts and don't knows of feedback for clinical education. Science.gov (United States) Lefroy, Janet; Watling, Chris; Teunissen, Pim W; Brand, Paul 2015-12-01 The guidelines offered in this paper aim to amalgamate the literature on formative feedback into practical Do's, Don'ts and Don't Knows for individual clinical supervisors and for the institutions that support clinical learning. The authors built consensus by an iterative process. Do's and Don'ts were proposed based on authors' individual teaching experience and awareness of the literature, and the amalgamated set of guidelines were then refined by all authors and the evidence was summarized for each guideline. Don't Knows were identified as being important questions to this international group of educators which if answered would change practice. The criteria for inclusion of evidence for these guidelines were not those of a systematic review, so indicators of strength of these recommendations were developed which combine the evidence with the authors' consensus. A set of 32 Do and Don't guidelines with the important Don't Knows was compiled along with a summary of the evidence for each. These are divided into guidelines for the individual clinical supervisor giving feedback to their trainee (recommendations about both the process and the content of feedback) and guidelines for the learning culture (what elements of learning culture support the exchange of meaningful feedback, and what elements constrain it?) Feedback is not easy to get right, but it is essential to learning in medicine, and there is a wealth of evidence supporting the Do's and warning against the Don'ts. Further research into the critical Don't Knows of feedback is required. A new definition is offered: Helpful feedback is a supportive conversation that clarifies the trainee's awareness of their developing competencies, enhances their self-efficacy for making progress, challenges them to set objectives for improvement, and facilitates their development of strategies to enable that improvement to occur. 9. Generation of the ECP database (ECP02.DAT) at the beginning of the cycle 1 of the Unit 1 of Laguna Verde; Generacion de la base ECP (ECP02.DAT) al inicio del ciclo 1 de la Unidad 1 de Laguna Verde Energy Technology Data Exchange (ETDEWEB) Perusquia C, R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico) 1992-10-15 In order to carrying out a comparison among the results provided for the Program of Estimate of the ECP Critical Position and the Shutdown/Startup produced in the Cycle 1 of the Unit 1 of Laguna Verde, it was generated the base of the ECP program, following the outlines settled down in the Procedure 'Generation of ECP Database for Laguna Verde' (IT.SN/DFR 074). Next the data sheets filled when being generated the ECP02.DAT database at the beginning of the cycle are provided. In the IT.SN/DFR 079 report 'Adjustment and Preliminary Evaluation of the Predictions of Criticity of the ECP Program with Reported Data of Cycle 1 of the Unit 1 of Laguna Verde, the results of the comparison among the estimates of the ECP program using the ECP02.DAT with the real data of the Cycle 1 of the Unit 1 of Laguna Verde are presented. (Author) 10. May 2012 Groundwater and Surface Water Sampling at the Rio Blanco, Colorado, Site (Data Validation Package) International Nuclear Information System (INIS) 2012-01-01 Annual sampling was conducted at the Rio Blanco, Colorado, site for the Long-Term Hydrologic Monitoring Program May 9-10, 2012, to monitor groundwater and surface water for potential radionuclide contamination. Sampling and analyses were conducted as specified in Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). A duplicate sample was collected from location Johnson Artesian WL. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry and for tritium using the conventional and enrichment methods. Results of this monitoring at the Rio Blanco site demonstrate that groundwater and surface water outside the site boundaries have not been affected by project-related contaminants. 11. Irradiation effect on α- and β-caseins of milk and Queso Blanco cheese determined by capillary electrophoresis International Nuclear Information System (INIS) Ham, J.S.; Jeong, S.G.; Lee, S.G.; Han, G.S.; Chae, H.S.; Yoo, Y.M.; Kim, D.H.; Lee, W.K.; Jo, C. 2009-01-01 Milk and Queso Blanco cheese were exposed to irradiation with doses of 1, 2, 3, 5, and 10 kGy to investigate the irradiation effect on α- and β-casein using a capillary electrophoresis. α S1 -Casein to total protein ratio in raw milk was decreased from 19.63% to 8.64% by 10 kGy of gamma irradiation. The ratio of α S1 - to α S0 -casein was also decreased from 1.38 to 0.53, which showed α S1 -casein is more susceptible to gamma irradiation than α S0 -casein. Similarly, α S1 -casein to total protein ratio in Queso Blanco cheese was decreased from 17.48% to 7.82% and the ratio of α S1 - to α S0 -casein was decreased from 1.16 to 0.43 by 10 kGy of gamma irradiation. Dose-dependent reduction of β A1 -casein was also found. β A1 -Casein to total protein ratios in raw milk and Queso Blanco cheese were decreased from 22.00% to 14.16% and from 21.96% to 13.89% after 10 kGy, respectively. The ratios of β A1 - to β A2 -casein were from 1.10 to 0.64 and 0.93 to 0.57 in milk and Queso Blanco cheese, respectively. However, α S0 -, β B -, and β A3 -casein increased by irradiation at 10 kGy. The results suggest that α S1 -casein and β A1 -casein were more susceptible to gamma irradiation, and may be related to the reduction of milk allergenicity caused by gamma irradiation 12. Chemical composition, antioxidant and antimicrobial activities of citrus jambhiri lush and citrus reticulata blanco essential oils International Nuclear Information System (INIS) Sadaf, S.; Shahid, M.; Iqbal, Z. 2009-01-01 The aim of this study was to investigate the time interval in which we can get maximum concentration of essential oil from the peels of Citrus jambhiri Lush and Citrus reticulata Blanco, to determine the composition of peel oils and to evaluate the antioxidant and antimicrobial activity of extracted oils. It was observed that in case of Citrus jambhiri Lush maximum oil yield (I %) was obtained when fruits were immature (during October). As the fruit samples got matured, the oil yield decreased. In December the oil yield decreased to 0.2 %. In case of Citrus reticulata Blanco maximum oil yield (0.189 %) was obtained during the last week of January. Chemical analysis of essential oils showed that limonene was the most abundant compound (86 %-93 %) followed by alpha terpinene (2 %-4.5 %), beta-pinene(1 0/0-2 %) and nerol (0.5 %-1.5 %). The radical scavenging and antioxidant activities of essential oils were determined by DPPH and linoleic acid test. The essential oil of Citrus jambhiri Lush inhibited the oxidation of linoleic acid by 54.98 % and that of Citrus reticulata Blanco inhibited by 49.98 %. Moreover, the essential oils also showed antimicrobial activities against the tested microorganisms. (author) 13. Tourism in Laguna (SC): Impacts and attitude. OpenAIRE Susana de Araujo Gastal; Sandra Dall'Agnol 2012-01-01 The places by the sea, as spaces of tourism and second homes, suffer the impacts from the activity. The local population attitude, seeing these places as bonuses or otherwise, as a burden, contributes to the viability of tourism in the locality. This article aims to present a research, methodologically related to attitude construct of social psychology, conducted in Laguna, Santa Catarina, Brazil to evaluate the relationship between the community and the different impacts caused by tourism,. ... 14. High-\\gamma$Beta Beams within the LAGUNA design study CERN Document Server Orme, Christopher 2010-01-01 Within the LAGUNA design study, seven candidate sites are being assessed for their feasibility to host a next-generation, very large neutrino observatory. Such a detector will be expected to feature within a future European accelerator neutrino programme (Superbeam or Beta Beam), and hence the distance from CERN is of critical importance. In this article, the focus is a$^{18}$Ne and$^{6}$He Beta Beam sourced at CERN and directed towards a 50 kton Liquid Argon detector located at the LAGUNA sites: Slanic (L=1570 km) and Pyh\\"{a}salmi (L=2300 km). To improve sensitivity to the neutrino mass ordering, these baselines are then combined with a concurrent run with the same flux directed towards a large Water \\v{C}erenkov detector located at Canfranc (L=650 km). This degeneracy breaking combination is shown to provide comparable physics reach to the conservative Magic Baseline Beta Beam proposals. For$^{18}$Ne ions boosted to$\\gamma=570$and$^{6}$He ions boosted to$\\gamma=350, the correct mass ordering can be... 15. Negative sequence relay applied to generator 1 of the Laguna Verde nuclear power plant; Aplicacion de un relevador de secuencia negativa en el generador 1 de la central de Laguna Verde Energy Technology Data Exchange (ETDEWEB) Diaz de la Serna P, Enrique [Instituto de Investigaciones Electricas, Cuernavaca (Mexico) 1988-12-31 The rotor of a synchronous generator can be dangerously heated in a short time by stator current unbalance, therefore it must be protected with a specific relay. This article discusses the protection and the adjustments selected for Unit 1 of the Comision Federal de Electricidad Laguna Verde Nuclear Nuclear Power Station. [Espanol] El rotor de un generador sincrono puede calentarse peligrosamente en un tiempo corto debido a desbalance de corrientes en el estator, por lo que debe protegerse con un relevador especifico. En este articulo se describen la proteccion y los ajustes seleccionados para la unidad 1, de la central nucleoelectrica Laguna Verde de la Comision Federal de Electricidad. 16. Modeling of the vapor cycle of Laguna Verde with the PEPSE code to conditions of thermal power licensed at present (2027 MWt); Modelado del ciclo de vapor de Laguna Verde con el codigo PEPSE a condiciones de potencia termica actualmente licenciada (2027 MWt) Energy Technology Data Exchange (ETDEWEB) Castaneda G, M. A.; Maya G, F.; Medel C, J. E.; Cardenas J, J. B.; Cruz B, H. J.; Mercado V, J. J., E-mail: [email protected] [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km 42.5, Veracruz (Mexico) 2011-11-15 By means of the use of the performance evaluation of power system efficiencies (PEPSE) code was modeled the vapor cycle of the nuclear power station of Laguna Verde to reproduce the nuclear plant behavior to conditions of thermal power, licensed at present (2027 MWt); with the purpose of having a base line before the implementation of the project of extended power increase. The model of the gauged vapor cycle to reproduce the nuclear plant conditions makes use of the PEPSE model, design case of the vapor cycle of nuclear power station of Laguna Verde, which has as main components of the model the great equipment of the vapor cycle of Laguna Verde. The design case model makes use of information about the design requirements of each equipment for theoretically calculating the electric power of exit, besides thermodynamic conditions of the vapor cycle in different points. Starting from the design model and making use of data of the vapor cycle measured in the nuclear plant; the adjustment factors were calculated for the different equipment s of the vapor cycle, to reproduce with the PEPSE model the real vapor cycle of Laguna Verde. Once characterized the model of the vapor cycle of Laguna Verde, we can realize different sensibility studies to determine the effects macros to the vapor cycle by the variation of certain key parameters. (Author) 17. Subsidence of the Laguna Salada Basin, northeastern Baja California, Mexico, inferred from Milankovitch climatic changes Energy Technology Data Exchange (ETDEWEB) Contreras, Juan; Martin-Barajas, Arturo [Departamento de Geologia, CICESE, Ensenada Baja California (Mexico); Herguera, Juan Carlos [Division de Oceanologia, CICESE, Ensenada Baja California (Mexico) 2005-01-15 Laguna Salada in northern Baja California, Mexico, is an active half-graben product of the trans-tensional tectonics of the Gulf of California. It is sensitive to changes in sediment supply from the Colorado River basin. We present a time series analysis of the upper 980 m of a gamma-ray log from a borehole drilled near the Laguna Salada fault. The power spectrum of the gammaray log resembles the spectrum of {delta}{sup 1}8{omicron} Pleistocene isotopic variations from ice cores and from the deep ocean, known to be strongly controlled by Milankovitch cycles. We correlate {delta}{sup 1}8{omicron} stages with silty and sandy intervals in the log. Downcore ages for the last 780 ky are constrained within {approx}10 kyr. We derive a simple time vs. depth calibration relation for the basin over this time interval. Estimated sedimentation rates at the drill site appear to be constant with a value of {approx}1.6 mm/yr. We propose that this subsidence rate is produced by the Laguna Salada fault. [Spanish] La cuenca de Laguna Salada en el norte de Baja California, Mexico, es un semigraben activo producto de la tectonica ranstensional del Golfo de California. Esta cuenca endorreica es sensible a cambios en sedimentacion por variaciones en el aporte e sedimentos de fuentes cercanas y distales transportados por arroyos de las sierras adyacentes y por el Rio Colorado. Esta cuenca es un sitio excepcional para explorar el uso de cambios climaticos ciclicos como herramienta de datacion y estimar tasas de sedimentacion y subsidencia en el area. Para demostrar esto se presenta un analisis de series de tiempo de un registro de rayos de gama de un pozo geotermico exploratorio perforado adyacente a la falla de Laguna Salada, la cual limita el margen oriental de la cuenca. Los resultados del analisis indican que el espectro de los primeros 980 m del registro de rayos gama tiene una alta coherencia con el espectro de registros isotopicos paleoclimaticos de {delta}{sup 1}8{omicron} del 18. Laguna Verde - A photo story Energy Technology Data Exchange (ETDEWEB) NONE 1980-04-15 Safety is one of the main factors in the construction and operation of a modern nuclear power plant. There are many barriers between the fission products produced in the fuel elements of the core, and the environment: the cladding of the fuel pins which are enclosed in the reactor core, the pressure vessel containing the core and which in turn is enclosed in the reactor containment, all this being located in a low-pressure secondary containment or reactor building. Despite these precautions, nuclear safety is still a widely-discussed issue. The important fact remains, however, that there has not been a single radiation-induced fatality or serious injury at any civilian nuclear power plant during 20 years of nuclear power generation. This includes the accident that occurred in March 1979 at the Three Mile Island nuclear plant in the USA. A substantial component contributing to safety in a nuclear power plant is the containment. The following photos of Laguna Verde, Mexico's first nuclear power station being constructed at Alta Lucero in Vera Cruz, give an impression of how strong this concrete and steel containment actually is. Laguna Verde consists of two 600 MWe units and the plant is scheduled for commercial operation in 1982. Construction began in 1974. Both units are boiling-water reactors. The photos show, in general, the construction of the primary containment for the reactors (the dry wells). The dry well contains the reactor itself and has two layers: the leak-tight steel liner and the heavy concrete building. The purpose of the primary containment is to retain steam and gases that might escape in an emergency and to direct these through relief tubes to a water pond for cooling. Surrounding this primary containment will be a reactor building which serves as a secondary low-pressure containment, able to operate at pressures up to 0.2 atmospheres. 19. CARACTERIZACIÓN COLORIMÉTRICA DEL MANJAR BLANCO DEL VALLE CARACTERIZAÇÃO COLORIMÉTRICA DE MANJAR BRANCO DEL VALLE COLORIMETRIC CHARACTERIZATION OF MANJAR BLANCO DEL VALLE Directory of Open Access Journals (Sweden) DIEGO FABIÁN NOVOA 2012-12-01 Full Text Available El Manjar Blanco del Valle originario de la región del Valle del Cauca en Colombia es considerado como símbolo gastronómico y cultural; es un tipo de dulce de leche con adición de almidón. El color es uno de los atributos más importantes en los alimentos. La medición del color tiene aplicaciones en el control de calidad y el desarrollo de nuevos productos. En esta investigación se caracteriza el color instrumental (escala CIE-L*a*b* del manjar blanco del Valle elaborado por empresas representativas y tradicionales de la región, mediante la determinación de los parámetros de color (L*, a*, b* de tres lotes de cada una de las marcas comerciales. También se caracterizó físicamente las muestras, encontrando pH entre 5,73 y 6,02 y grados Brix entre 65,16 y 76,47. Los valores promedio de los parámetros de color determinados experimentalmente para el manjar blanco fueron: L* 43,60, a* 14,58 y b* 34,67. De los datos reportados en este trabajo se concluye que existe una variabilidad considerable en el color entre lotes y marcas comerciales, lo que evidencia la necesidad de establecer procedimientos de estandarización en la producción y en la materia prima, con el fin de lograr un producto con características similares.O Manjar Branco Del Valle originário da região do Vale de Cauca na Colômbia é considerado um símbolo gastronômico e cultural; é um tipo de doce de leite com adição de amido. A coloração é um dos atributos mais importantes nos alimentos. A determinação da cor tem aplicações no controle de qualidade e no desenvolvimento de novos produtos. Neste estudo se caracterizou a cor instrumental (Sistema CIE-L*a*b* do Manjar Branco Del Valle produzido por empresas representativas e tradicionais da região, mediante a determinação dos parâmetros de cor (L*, a*, b* de três lotes de cada uma das marcas comerciais. Também se caracterizou fisicamente as amostras, encontrando pH entre 5,73 e 6,02 e graus Brix entre 65 20. Waterbirds (other than Laridae nesting in the middle section of Laguna Cuyutlán, Colima, México Directory of Open Access Journals (Sweden) Eric Mellink 2008-03-01 Full Text Available Laguna de Cuyutlán, in the state of Colima, Mexico, is the only large coastal wetland in a span of roughly 1150 km. Despite this, the study of its birds has been largely neglected. Between 2003 and 2006 we assessed the waterbirds nesting in the middle portion of Laguna Cuyutlán, a large tropical coastal lagoon, through field visits. We documented the nesting of 15 species of non-Laridae waterbirds: Neotropic Cormorant (Phalacrocorax brasilianus, Tricolored Egret (Egretta tricolor, Snowy Egret (Egretta thula, Little Blue Heron (Egretta caerulea, Great Egret (Ardea alba, Cattle Egret (Bubulcus ibis, Black-crowned Nightheron (Nycticorax nycticorax, Yellow-crowned Night-heron (Nyctanassa violacea, Green Heron (Butorides virescens, Roseate Spoonbill (Platalea ajaja, White Ibis (Eudocimus albus, Black-bellied Whistling-duck (Dendrocygna autumnalis, Clapper Rail (Rallus longirostris, Snowy Plover (Charadrius alexandrinus, and Black-necked Stilt (Himantopus mexicanus. These add to six species of Laridae known to nest in that area: Laughing Gulls (Larus atricilla, Royal Terns (Thalasseus maximus, Gull-billed Terns (Gelochelidon nilotica, Forster’s Terns (S. forsteri, Least Terns (Sternula antillarum, and Black Skimmer (Rynchops niger, and to at least 57 species using it during the non-breeding season. With such bird assemblages, Laguna Cuyutlán is an important site for waterbirds, which should be given conservation status. Rev. Biol. Trop. 56 (1: 391-397. Epub 2008 March 31.Durante la prospección de la parte media de la Laguna Cuyutlán, una gran laguna costera en Colima, México, entre 2003 y 2006, documentamos la anidación de 15 especies de aves acuáticas que no pertenecer a la familia Laridae: Phalacrocorax brasilianus, Egretta tricolor, Egretta thula, Egretta caerulea, Ardea alba, Bubulcus ibis, Nycticorax nycticorax, Nyctanassa violacea, Butorides virescens, Platalea ajaja, Eudocimus albus, Dendrocygna autumnalis, Rallus longirostris 1. Microbial biotransformation of DON: molecular basis for reduced toxicity Science.gov (United States) Pierron, Alix; Mimoun, Sabria; Murate, Leticia S.; Loiseau, Nicolas; Lippi, Yannick; Bracarense, Ana-Paula F. L.; Schatzmayr, Gerd; He, Jian Wei; Zhou, Ting; Moll, Wulf-Dieter; Oswald, Isabelle P. 2016-07-01 Bacteria are able to de-epoxidize or epimerize deoxynivalenol (DON), a mycotoxin, to deepoxy-deoxynivalenol (deepoxy-DON or DOM-1) or 3-epi-deoxynivalenol (3-epi-DON), respectively. Using different approaches, the intestinal toxicity of 3 molecules was compared and the molecular basis for the reduced toxicity investigated. In human intestinal epithelial cells, deepoxy-DON and 3-epi-DON were not cytotoxic, did not change the oxygen consumption or impair the barrier function. In intestinal explants, exposure for 4 hours to 10 μM DON induced intestinal lesions not seen in explants treated with deepoxy-DON and 3-epi-DON. A pan-genomic transcriptomic analysis was performed on intestinal explants. 747 probes, representing 323 genes, were differentially expressed, between DON-treated and control explants. By contrast, no differentially expressed genes were observed between control, deepoxy-DON and 3-epi-DON treated explants. Both DON and its biotransformation products were able to fit into the pockets of the A-site of the ribosome peptidyl transferase center. DON forms three hydrogen bonds with the A site and activates MAPKinases (mitogen-activated protein kinases). By contrast deepoxy-DON and 3-epi-DON only form two hydrogen bonds and do not activate MAPKinases. Our data demonstrate that bacterial de-epoxidation or epimerization of DON altered their interaction with the ribosome, leading to an absence of MAPKinase activation and a reduced toxicity. 2. Considerations for increasing unit 1 spent fuel pool capacity at the Laguna Verde station International Nuclear Information System (INIS) Vera, A. 1992-01-01 To increase the spent fuel storage capacity at the Laguna Verde Station in a safe and economical manner and assure a continuous operation of the first Mexican Nuclear Plant, Comision Federal de Electricidad (CFE), the Nation's Utility, seeked alternatives considering the overall world situation, the safety and licensing aspects, as well as the economics and the extent of the nuclear program of Mexico. This paper describes the alternatives considered, their evaluation and how the decision taken by CFE in this field, provides the Laguna Verde Station with a maximum of 37 years storage capacity plus full core reserve 3. El viaje al norte y el peso de la historia. Las identidades de Blanco White en sus Letters from Spain (1822 = The Journey to the North and the Importance of History. Blanco White’s Identities in Letters from Spain (1822 Directory of Open Access Journals (Sweden) Xavier Andreu Miralles 2016-12-01 Full Text Available ResumenEn las primeras décadas del siglo XIX, José María Blanco White reescribió y reconstruyó sus múltiples identidades, individuales y colectivas, e intentó fijar en relación con ellas un relato de su vida, siempre inestable. Este texto sitúa su obra y, en particular, sus Letters from Spain (1822, en el marco del debate europeo sobre los caracteres nacionales. Un debate que descansaba, en buena medida, en esa concepción escindida de Europa en la que el Sur mediterráneo «atrasado» funcionaba como una contrapartida especular del Norte «moderno». La obra de Blanco White nos permite analizar cómo dicha concepción influyó en cómo se pensaron y construyeron las identidades en la Europa de principios del siglo XIX.AbstractAt the beginning of the nineteenth-century, José María Blanco White rewrote and reconstructed his multiple identities, individual as much as collective. He tried to lay down the tale of his life, a tale that was always unsteady. This article connects his work, and especially his Letters from Spain (1822, with the European debate on national characters. To a large extent, this debate was based on an understanding of Europe in which the Mediterranean backward South worked as an opposite mirror for the modern North. Through the work of Blanco White we can analyse how this understanding influenced the way in which identities were designed and constructed in the Europe of the first decades of the nineteenth century. 4. Origin and evolution of the Laguna Potrok Aike maar (Patagonia, Argentina) Science.gov (United States) Gebhardt, A. C.; de Batist, M.; Niessen, F.; Anselmetti, F. S.; Ariztegui, D.; Ohlendorf, C.; Zolitschka, B. 2009-04-01 Laguna Potrok Aike, a maar lake in southern-most Patagonia, is located at about 110 m a.s.l. in the Pliocene to late Quaternary Pali Aike Volcanic Field (Santa Cruz, southern Patagonia, Argentina) at about 52°S and 70°W, some 20 km north of the Strait of Magellan and approximately 90 km west of the city of Rio Gallegos. The lake is almost circular and bowl-shaped with a 100 m deep, flat plain in its central part and an approximate diameter of 3.5 km. Steep slopes separate the central plain from the lake shoulder at about 35 m water depth. At present, strong winds permanently mix the entire water column. The closed lake basin contains a sub saline water body and has only episodic inflows with the most important episodic tributary situated on the western shore. Discharge is restricted to major snowmelt events. Laguna Potrok Aike is presently located at the boundary between the Southern Hemispheric Westerlies and the Antarctic Polar Front. The sedimentary regime is thus influenced by climatic and hydrologic conditions related to the Antarctic Circumpolar Current, the Southern Hemispheric Westerlies and sporadic outbreaks of Antarctic polar air masses. Previous studies demonstrated that closed lakes in southern South America are sensitive to variations in the evaporation/precipitation ratio and have experienced drastic lake level changes in the past causing for example the desiccation of the 75 m deep Lago Cardiel during the Late Glacial. Multiproxy environmental reconstruction of the last 16 ka documents that Laguna Potrok Aike is highly sensitive to climate change. Based on an Ar/Ar age determination, the phreatomagmatic tephra that is assumed to relate to the Potrok Aike maar eruption was formed around 770 ka. Thus Laguna Potrok Aike sediments contain almost 0.8 million years of climate history spanning several past glacial-interglacial cycles making it a unique archive for non-tropical and non-polar regions of the Southern Hemisphere. In particular, variations of 5. Irradiation effect on {alpha}- and {beta}-caseins of milk and Queso Blanco cheese determined by capillary electrophoresis Energy Technology Data Exchange (ETDEWEB) Ham, J.S.; Jeong, S.G.; Lee, S.G.; Han, G.S.; Chae, H.S.; Yoo, Y.M.; Kim, D.H. [Animal Food Processing Division, National Institute of Animal Science, Suwon 441-706 (Korea, Republic of); Lee, W.K. [College of Veterinary Medicine, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Jo, C. [Department of Animal Science and Biotechnology, Chungnam National University, Daejeon 305-764 (Korea, Republic of)], E-mail: [email protected] 2009-02-15 Milk and Queso Blanco cheese were exposed to irradiation with doses of 1, 2, 3, 5, and 10 kGy to investigate the irradiation effect on {alpha}- and {beta}-casein using a capillary electrophoresis. {alpha}{sub S1}-Casein to total protein ratio in raw milk was decreased from 19.63% to 8.64% by 10 kGy of gamma irradiation. The ratio of {alpha}{sub S1}- to {alpha}{sub S0}-casein was also decreased from 1.38 to 0.53, which showed {alpha}{sub S1}-casein is more susceptible to gamma irradiation than {alpha}{sub S0}-casein. Similarly, {alpha}{sub S1}-casein to total protein ratio in Queso Blanco cheese was decreased from 17.48% to 7.82% and the ratio of {alpha}{sub S1}- to {alpha}{sub S0}-casein was decreased from 1.16 to 0.43 by 10 kGy of gamma irradiation. Dose-dependent reduction of {beta}{sub A1}-casein was also found. {beta}{sub A1}-Casein to total protein ratios in raw milk and Queso Blanco cheese were decreased from 22.00% to 14.16% and from 21.96% to 13.89% after 10 kGy, respectively. The ratios of {beta}{sub A1}- to {beta}{sub A2}-casein were from 1.10 to 0.64 and 0.93 to 0.57 in milk and Queso Blanco cheese, respectively. However, {alpha}{sub S0}-, {beta}{sub B}-, and {beta}{sub A3}-casein increased by irradiation at 10 kGy. The results suggest that {alpha}{sub S1}-casein and {beta}{sub A1}-casein were more susceptible to gamma irradiation, and may be related to the reduction of milk allergenicity caused by gamma irradiation. 6. Don Gonzalo Jimenez de Quesada. El Fundador Directory of Open Access Journals (Sweden) Alvaro López Pardo 1989-09-01 Full Text Available Discurso pronunciado por el Doctor Alvaro López Pardo Presidente de la Academia de Historia de Bogotá, al Consejo de Bogotá el día 6 de agosto de 1988. Sesión especial de los 450 años. Por el año de 1578, caminaba lentamente por las polvorientas calles del poblado de Mariquita, un anciano, casi octogenario, que mostraba en su piel huellas de un enfermedad que se decía era la de San Lázaro. Las gentes lo miraban pasar con una mezcla de respeto y de piedad. En su mirada, un tanto vaga, se podían apreciar destellos de la que fuera una recia personalidad. Esta pobre figura era nadie menos que el Mariscal Don Gonzalo Jiménez de Quesada. En esta población ardiente y lejana, cargado de deudas, sin techo propio, iba a morir el gran señor, el Gran Capitán, el Gran Aventurero que fundara ésta nuestra noble y muy leal Santa Fe de Bogotá, cuyos 450 años celebramos en este día. Parece increíble que en aquella época y con una agitada vida, Don Gonzalo hubiera llegado a tan avanzada edad, es muestra de la fuerza de una raza y del templo de su espíritu, que se sobreponía a todas las adversidades y contratiempos. ¿Qué recuerdos vendrían a la mente de este anciano cuando, sentado en una pobre silla de vaqueta, contempla el azul cielo del trópico? ¿Quizá su infancia en España, en Córdoba, donde naciera o en la imponente Granada de los moros, recuperada hacía unos años por la Reina Isabel. Viendo los jardines de la Alhambra, el Generalife y al fondo el blanco perpetuo de la Sierra Nevada. O vendría a su mente el paso del fúnebre cortejo de Felipe el Hermoso y su lunática viuda Doña Juana? Sería tal vez el periodo de su juventud, oyendo las aventuras de Cortés en la Conquista de México, en medio de una Europa convulsionada y con España como centro de la misma. O quizás cuando estudiaba leyes en Salamanca y se metía en pleitos que no siempre ganaba y como 7. Los sindicatos blancos de Monterrey (1931-2009 Directory of Open Access Journals (Sweden) Miguel Ángel Ramírez Sánchez 2011-01-01 Full Text Available Los sindicatos blancos son el equivalente mexicano a los sindicatos amarillos de Francia y España y a los planes de representación del empleado de Estados Unidos y Canadá. De ellos se dice que son organismos obreros sometidos a la voluntad de los patrones, que los crean y dirigen. En México, esta clase de sindicatos eran hasta hace poco un fenómeno regional, restringido a la ciudad de Monterrey, donde han tenido su mayor desarrollo. Sin embargo, coincidiendo con la crisis y reorganización del sindicalismo mexicano y la apertura del sistema político nacional, han crecido en número e influencia política. En este artículo se ofrece un resumen histórico de este movimiento. 8. Simulation of the electric systems of the Laguna Verde nuclear power station; Simulacion de los sistemas electricos de la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Rodriguez Lozano, Saul; Ruiz Ponce, Gerardo E [Instituto de Investigaciones Electricas, Cuernavaca (Mexico) 1992-03-01 In this article, the electric system models of the Laguna Verde Nuclear Power Station (CNLV) simulator, are presented. These models permit the functioning simulation, in the different operation modes of the main generator (Ruiz and Rodriguez 1991a), of the auxiliaries system and of the substation (Ruiz and Rodriguez 1991b), and of the emergency diesel generators system (Ruiz and Rodriguez 1991c). The general characteristics of such systems, considered as the basis to obtain the representative models, which were developed as modules in an independent way to be integrated in the simulator, are also described. [Espanol] En este articulo, se presenta los modelos de los sistemas electricos del simulador de la Central Laguna Verde (CLV). Estos modelos permiten simular el funcionamiento, en los diferentes modos de operacion del generador principal (Ruiz y Rodriguez, 1991a), del sistema de auxiliares y de la subestacion (Ruiz y Rodriguez, 1991b) y del sistema de generadores diesel de emergencia (Ruiz y Rodriguez, 1991c). Asimismo, se describen las caracteristicas generales de tales sistemas, consideradas como la base para obtener los modelos representativos, los cuales fueron desarrollados como modulos en forma independiente para integrarse al simulador. 9. ASPECTOS HIDROLOGICOS DE LAS LAGUNAS DE ATASTA Y POM, MEXICO Directory of Open Access Journals (Sweden) Alejandro Ruiz-MarÃn 2009-01-01 Full Text Available Las lagunas de Pom y Atasta forman parte del área natural protegida de flora y fauna laguna de Términos en la región de Campeche, México. Esta es una importante área ecológica ya que es el habitad de muchas especies nativas y migratorias. Estas lagunas han sido afectadas por actividades industriales y por descargas de aguas residuales. Monitoreo de nitrógeno, fósforo y coliformes fecales en agua superficial fueron realizados a lo largo de ambas lagunas durante las temporadas de seca, lluvia y nortes durante un año. Las altas temperaturas en verano (31 ºC y mÃnimas en nortes (25ºC fueron asociadas con valores de oxigeno disuelto (5.1 y 6.3 mg l-1, respectivamente indicando también una probable relación con la actividad fitoplanctonica. El pH (8.0-8.2 y la salinidad (0.32 - 3.48 UPS no mostraron variación significativa entre las tres temporadas climáticas. El nivel de amonio no fue mayor a los valores sugeridos para el control de eutroficación (0.1 mg l-1, mientras que los niveles de fósforo fueron de mayor concentración (2.0-3.5 mg l-1 que aquellos considerados seguros (0.01-0.125 mg l-1 para el medio ambiente. Las más altas concentraciones de N y P cerca de las áreas habitadas sugiere un importante contribución de nutrientes provenientes de aguas de desecho, asociado con la descomposición de material orgánico. La concentración de coliformes fecales durante la temporada de lluvias y nortes (8.0-26.0 MPN 100 ml-1 fue mayor que durante la temporada de seca (1.3-3.5 MPN 100 ml-1 sugiriendo un importante acceso por escurrimiento pluvial y aguas residuales no tratadas proveniente de las áreas cercanas al lago habitadas. La deforestación de manglares y la descontrolada actividad de agricultura afectaran la calidad del agua en ambos lagos en el futuro. 10. Design optimization for fuel reloading in Laguna Verde nuclear power plant International Nuclear Information System (INIS) Cortes Campos, C.C.; Montes Tadeo, J.L. 1991-01-01 Procedure followed to perform the design optimation in fuel reloading is described in general words and also is shown an example in which such procedure was uses for analysis of BWR type reactor in unit 1 of Laguna Verde nuclear power plant (Author) 11. Geologic framework, hydrostratigraphy, and ichnology of the Blanco, Payton, and Rough Hollow 7.5-minute quadrangles, Blanco, Comal, Hays, and Kendall Counties, Texas Science.gov (United States) Clark, Allan K.; Golab, James A.; Morris, Robert E. 2016-09-13 This report presents the geologic framework, hydrostratigraphy, and ichnology of the Trinity and Edwards Groups in the Blanco, Payton, and Rough Hollow 7.5-minute quadrangles in Blanco, Comal, Hays, and Kendall Counties, Texas. Rocks exposed in the study area are of the Lower Cretaceous Trinity Group and lower part of the Fort Terrett Formation of the Lower Cretaceous Edwards Group. The mapped units in the study area are the Hammett Shale, Cow Creek Limestone, Hensell Sand, and Glen Rose Limestone of the Trinity Group and the lower portion of the Fort Terrett Formation of the Edwards Group. The Glen Rose Limestone is composed of the Lower and Upper Members. These Trinity Group rocks contain the upper and middle Trinity aquifers. The only remaining outcrops of the Edwards Group are the basal nodular member of the Fort Terrett Formation, which caps several hills in the northern portion of the study area. These rocks were deposited in an open marine to supratidal flats environment. The faulting and fracturing in the study area are part of the Balcones fault zone, an extensional system of faults that generally trends southwest to northeast in south-central Texas.The hydrostratigraphic units of the Edwards and Trinity aquifers were mapped and described using a classification system based on fabric-selective or not-fabric-selective porosity types. The only hydrostratigraphic unit of the Edwards aquifer present in the study area is hydrostratigraphic unit VIII. The mapped hydrostratigraphic units of the upper Trinity aquifer are (from top to bottom) the Camp Bullis, upper evaporite, fossiliferous, and lower evaporite which are interval equivalent to the Upper Member of the Glen Rose Limestone. The middle Trinity aquifer encompasses (from top to bottom) the Lower Member of the Glen Rose Limestone, the Hensell Sand Member, and the Cow Creek Limestone Member of the Pearsall Formation. The Lower Member of the Glen Rose Limestone is subdivided into six informal hydro 12. DURABILIDAD DEL CEMENTO PORTLAND BLANCO ADICIONADO CON PIGMENTO AZUL ULTRAMAR Directory of Open Access Journals (Sweden) CAROLINA GIRALDO 2010-01-01 Full Text Available El pigmento Azul Ultramar (AU es un aluminosilicato polisulfurado de sodio que reacciona con el aluminato tricálcico (C3A y con el óxido de calcio (CaO del cemento Pórtland blanco en presencia de agua, generando cantidades considerables de etringita a edad temprana y en menor proporción de tobermorita. Esta etringita primaria se presenta en forma de fibras no orientadas mejorando el desempeño mecánico de los morteros, y al mismo tiempo dejando pocas cantidades de C3A disponible para la formación de etringita secundaria. En esta investigación se evalúa la durabilidad a diferentes edades de curado en morteros de cemento Portland blanco sustituidos por 0%, 10% y 20% de AU en peso, mediante pruebas de succión capilar y evaluación del cambio longitudinal de morteros expuestos a una solución de sulfato de sodio con una concentración del 5% (ASTM C1012. Los resultados evidencian una mayor resistencia a compresión y a flexión, una significativa disminución de la expansión y una reducción hasta del 800% de la absorción de agua en morteros con AU. Todo esto debido a la formación de las fases minerales adicionales (etringita primaria y tobermorita, las cuales fueron identificadas mediante microscopía electrónica de barrido (SEM. 13. Implementacion de modulos constructivistas que atiendan "misconceptions" y lagunas conceptuales en temas de la fisica en estudiantes universitarios Science.gov (United States) Santacruz Sarmiento, Neida M. Este estudio se enfoco en los "misconception" y lagunas conceptuales en temas fundamentales de Fisica como son Equilibrio Termodinamico y Estatica de fluidos. En primer lugar se trabajo con la identificacion de "misconceptions" y lagunas conceptuales y se analizo en detalle la forma en que los estudiantes construyen sus propias teorias de fenomenos relacionados con los temas. Debido a la complejidad en la que los estudiantes asimilan los conceptos fisicos, se utilizo el metodo de investigacion mixto de tipo secuencial explicativo en dos etapas, una cuantitativa y otra cualitativa. La primera etapa comprendio cuatro fases: (1) Aplicacion de una prueba diagnostica para identificar el conocimiento previo y lagunas conceptuales. (2) Identificacion de "misconceptions" y lagunas del concepto a partir del conocimiento previo. (3) Implementacion de la intervencion por medio de modulos en el topico de Equilibrio Termodinamico y Estatica de Fluidos. (4) Y la realizacion de la pos prueba para analizar el impacto y la efectividad de la intervencion constructivista. En la segunda etapa se utilizo el metodo de investigacion cualitativo, por medio de una entrevista semiestructurada que partio de la elaboracion de un mapa conceptual y se finalizo con un analisis de datos conjuntamente. El desarrollo de este estudio permitio encontrar "misconceptions" y lagunas conceptuales a partir del conocimiento previo de los estudiantes participantes en los temas trabajados, que fueron atendidos en el desarrollo de las distintas actividades inquisitivas que se presentaron en el modulo constructivista. Se encontro marcadas diferencias entre la pre y pos prueba en los temas, esto se debio al requerimiento de habilidades abstractas para el tema de Estatica de Fluidos y al desarrollo intuitivo para el tema de Equilibrio Termodinamico, teniendo mejores respuestas en el segundo. Los participantes demostraron una marcada evolucion y/o cambio en sus estructuras de pensamiento, las pruebas estadisticas 14. Eficiencia del tratamiento de residuales porcinos en digestores de laguna tapada Directory of Open Access Journals (Sweden) D Blanco Full Text Available Se evaluó la eficiencia de dos lagunas tapadas, diseñadas para tratar los residuales de las granjas porcinas P-3 y T-2.1 _pertenecientes a la Asociación de Porcicultores de Yucatán, México_, con el objetivo de verificar la factibilidad de implementar en Cuba esta tecnología. Los indicadores físico-químicos y microbiológicos de los efluentes fueron determinados en el momento de su entrada y su salida de los digestores, y a su salida del lago de estabilización. El digestor de la granja P-3 logró remover más del 90 % de la demanda química de oxígeno (DQO y hasta el 71 % de los sólidos suspendidos totales (SST presentes; mientras que el digestor de la granja T-2.1 alcanzó una remoción del 78 % en la DQO y el 62 % de los SST. Los análisis sanitarios indicaron que las bacterias coliformes totales presentaron una disminución importante, de 2,4 x 108 a 1,7 x 103 en la granja P-3 y de 4,2 x 107 a 2,7 x 103 en la granja T-2.1. En ambas lagunas, los huevos de helmintos mostraron una reducción del 100 %. Se concluye que las lagunas tapadas tuvieron un adecuado desempeño en el tratamiento de los residuales porcinos, y que esta tecnología es factible de ser empleada en Cuba. 15. Fitoplancton y aspectos físicos y químicos de la laguna de Chingaza en Cundinamarca, Colombia Fitoplancton y aspectos físicos y químicos de la laguna de Chingaza en Cundinamarca, Colombia Directory of Open Access Journals (Sweden) Donato R. John Charles 1991-12-01 Full Text Available En la laguna de Chingaza (3265 m alt. Cordillera Oriental Colombiana, se realizaron muestreos de fitoplancton, mediciones de temperatura, oxígeno y parámetros físicos y químicos. La comunidad de fitoplancton comprende principalmente Desmidiaceae, Bacillariophyceae, y Cyanophyceae: La Desmidiacea Closterium sp. es la dominante durante la mayor parte del muestreo, pero en octubre (1989 la Cianofícea Oscillatoria sp. es la más significativa. En esta misma época la laguna presenta estratificación térmica y deficiencia de nitrógeno en sus aguas. Debido a los bajos valores en la relación nitrógeno/fósforo, conductividad, sólidos disueltos, acidez y ciertos organismos indicadores la laguna de chingaza es oligotrófica. At the Chingaza pond (3.265 m alt., located on the eastern Colombian cordillera, samples and measurements of temperature, oxygen, and physical-chemical parameters were taken. Phytoplankton community mainly consisted of Desmidiaceae, Bacillariophyceae, and Cyanophceae. Desmidiaceae species dominated in most samples, but in october (1989 Oscillatoria sp. (Cyanophyceae was the most abundant species. During the latter period the laguna exhibited strong thermal stratification and its inorganic nitrogen content was extremely low. It is believed that this is a good example of an oligotrophic pond given the presence of certain bioindicators, the low nitrogen/phosphorus ratio, conductivity, and quantity of suspended solids. 16. The Metabolic Fate of Deoxynivalenol and Its Acetylated Derivatives in a Wheat Suspension Culture: Identification and Detection of DON-15-O-Glucoside, 15-Acetyl-DON-3-O-Glucoside and 15-Acetyl-DON-3-Sulfate Directory of Open Access Journals (Sweden) Clemens Schmeitzl 2015-08-01 Full Text Available Deoxynivalenol (DON is a protein synthesis inhibitor produced by the Fusarium species, which frequently contaminates grains used for human or animal consumption. We treated a wheat suspension culture with DON or one of its acetylated derivatives, 3-acetyl-DON (3-ADON, 15-acetyl-DON (15-ADON and 3,15-diacetyl-DON (3,15-diADON, and monitored the metabolization over a course of 96 h. Supernatant and cell extract samples were analyzed using a tailored LC-MS/MS method for the quantification of DON metabolites. We report the formation of tentatively identified DON-15-O-β-D-glucoside (D15G and of 15-acetyl-DON-3-sulfate (15-ADON3S as novel deoxynivalenol metabolites in wheat. Furthermore, we found that the recently identified 15-acetyl-DON-3-O-β-D-glucoside (15-ADON3G is the major metabolite produced after 15-ADON challenge. 3-ADON treatment led to a higher intracellular content of toxic metabolites after six hours compared to all other treatments. 3-ADON was exclusively metabolized into DON before phase II reactions occurred. In contrast, we found that 15-ADON was directly converted into 15-ADON3G and 15-ADON3S in addition to metabolization into deoxynivalenol-3-O-β-D-glucoside (D3G. This study highlights significant differences in the metabolization of DON and its acetylated derivatives. 17. Electrical Systems at Laguna Verde Nuclear Power Plant (LVNPP) after the Fukushima accident International Nuclear Information System (INIS) Lopez Jimenez, Jose Francisco 2015-01-01 During the accident occurred in Fukushima Daiichi Nuclear Power Station in Japan, the onsite and offsite electrical systems were affected and lost for a long time with irreversible consequences, therefore, the Mexican Regulatory Body known as the National Commission for Nuclear Safety and Safeguards (CNSNS: for its acronym in Spanish) has taken several actions to review the current capacity of the electrical systems installed at Laguna Verde NPP to cope with an event beyond of the design basis. The first action was to require to Laguna Verde NPP the compliance with Information Notice 2011-05 'Tohoku-Taiheiyou-Oki earthquake effects on Japanese Nuclear Power Plants' and with 10 CFR 50.54 'Conditions of licenses' section 'hh', both documents were issued by the United States Nuclear Regulatory Commission (USNRC). Additionally, CNSNS has taken into account the response actions emitted by other countries after the Fukushima accident. This involved the review of documents generated by Germany, Canada, United Arab Emirates, Finland, France, the United Kingdom and the Western European Nuclear Regulator's Association (WENRA). CNSNS made special inspections to verify the current capacity of the electrical systems of AC and DC. As a result of these inspections, CNSNS issued requirements that must be addressed by Laguna Verde NPP to demonstrate that it has the capacity to cope with events beyond the design basis. Parallel to the above, Mexico has participated in the Ibero-american Forum to address matters related to the 'Resistance Tests', the evaluations of the Forum have reached similar conclusions to those required by European Nuclear Safety Regulators Group (ENSREG), under the format proposed by WENRA. The actions carried out here are closely linked to the requirements established by the USNRC. It is also important to mention that: 1) the Extended Power Up-rate project was implemented in both Units of the Laguna Verde NPP before 18. Composición por especies y tallas de los peces en la laguna Barra de Navidad, Pacífico central mexicano Directory of Open Access Journals (Sweden) Gaspar González-Sansón 2014-03-01 Full Text Available Las lagunas costeras son consideradas áreas de crianza importantes para muchas especies de peces costeros. La laguna costera Barra de Navidad (3.76km² es importante para la economía local y soporta un desarrollo turístico y pesquerías artesanales. Sin embargo, el rol de esta laguna en la dinámica de las poblaciones de peces costeros es poco conocido. Los objetivos de la investigación fueron: caracterizar el agua de la laguna y las condiciones climáticas relacionadas, elaborar el elenco sistemático de la ictiofauna y estimar la proporción de juveniles en el total de individuos capturados de las especies más abundantes. Las operaciones de recolecta de peces se realizaron entre marzo 2011 y febrero 2012. Se utilizaron varios artes de pesca diferentes que incluyeron atarraya, chinchorro playero y redes de agalla con cuatro tamaños de malla diferentes. Se midieron las variables físicas y químicas en épocas de lluvias y de secas. La laguna es euhalina (salinidad 30-40 ups la mayor parte del tiempo, aunque en determinados periodos cortos puede tener características mixopolihalinas (salinidad 18-30 ups. Las concentraciones de clorofila y nutrientes indican que la laguna está eutrofizada. La temperatura media del agua varió estacionalmente de 24.9°C (abril, pleamar a 31.4°C (octubre, bajamar. Se recolectaron en total 36 448 individuos, pertenecientes a 92 especies, de las cuales 31 tienen una relevancia ecológica con base en el número de individuos capturados. Las especies dominantes fueron: Anchoa spp. (44.6%, Diapterus peruvianus (10.5%, Eucinostomus currani (8.1%, Cetengraulis mysticetus (7.8%, Mugil curema (5.2% y Opisthonema libertate (4.5%. La laguna es un hábitat de juveniles importante para 22 de las 31 especies más abundantes. Estas incluyeron algunas especies de importancia comercial como los pargos (Lutjanus argentiventris, L. colorado y L. novemfasciatus, el robalo (Centropomus nigrescens y la lisa (Mugil curema. Otras 19. Guidelines : the do's, don'ts and don't knows of feedback for clinical education NARCIS (Netherlands) Lefroy, Janet; Watling, Chris; Teunissen, Pim W; Brand, Paul 2015-01-01 INTRODUCTION: The guidelines offered in this paper aim to amalgamate the literature on formative feedback into practical Do's, Don'ts and Don't Knows for individual clinical supervisors and for the institutions that support clinical learning. METHODS: The authors built consensus by an iterative 20. Gamma thermometer longevity test: Laguna Verde 2 instruments recent performance International Nuclear Information System (INIS) Cuevas V, G.; Avila N, A.; Calleros M, G. 2013-10-01 This paper is informative of the General Electric Hitachi and Global Nuclear Fuel - Americas are collaboration with Comision Federal de Electricidad in a longevity test of thermocouples as power monitoring devices. The test conclusions will serve for final engineering design in detailing the Automated Fixed In-core Probes for calibration of the Local Power Range Monitors (LPRMs) of the Economic Simplified Boiling Water Reactor. This paper introduces the collaboration description and some recent performance evaluation of the thermocouples that are sensitive to gamma radiation and are known generically as Gamma Thermometers (G T). The G Ts in Laguna Verde 2 are radially located inside six instrumentation tubes in the core and consist of seven thermocouples, four are aligned with the LPRM heights and three are axially located between LPRM heights. The Laguna Verde 2 G T test has become the longest test of thermocouples as power monitoring devices in a BWR industry history and confirms their reliability in terms of time-dependent small noise under steady state reactor conditions and good agreement against Traversing In-core Probes power measurements. (Author) 1. Gamma thermometer longevity test: Laguna Verde 2 instruments recent performance Energy Technology Data Exchange (ETDEWEB) Cuevas V, G. [Global Nuclear Fuel, Americas, 3901 Castle Hayne Road, Wilmington, North Carolina (United States); Avila N, A.; Calleros M, G., E-mail: [email protected] [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verda, Carretera Veracruz-Nautla Km 42.5, Alto Lucero, Veracruz (Mexico) 2013-10-15 This paper is informative of the General Electric Hitachi and Global Nuclear Fuel - Americas are collaboration with Comision Federal de Electricidad in a longevity test of thermocouples as power monitoring devices. The test conclusions will serve for final engineering design in detailing the Automated Fixed In-core Probes for calibration of the Local Power Range Monitors (LPRMs) of the Economic Simplified Boiling Water Reactor. This paper introduces the collaboration description and some recent performance evaluation of the thermocouples that are sensitive to gamma radiation and are known generically as Gamma Thermometers (G T). The G Ts in Laguna Verde 2 are radially located inside six instrumentation tubes in the core and consist of seven thermocouples, four are aligned with the LPRM heights and three are axially located between LPRM heights. The Laguna Verde 2 G T test has become the longest test of thermocouples as power monitoring devices in a BWR industry history and confirms their reliability in terms of time-dependent small noise under steady state reactor conditions and good agreement against Traversing In-core Probes power measurements. (Author) 2. Influencia del citoplasma sobre la expresión del centro blanco y temperatura de gelatinización en arroz (Oryza sativa. L. Directory of Open Access Journals (Sweden) Baena García Diosdado 1995-12-01 Full Text Available La investigación se adelantó en el Centro Internacional de Agricultura Tropical (CIAT durante 1989-1991. No hubo influencia del citoplasma en la expresión del centro blanco y temperatura de gelatinización. El orden de dominancia El orden de dominancia de los progenitores para el carácter ausencia de centro blanco fue Colombia 1 > 1R5 = L6850 > IRAT8. El cultivo in vitro influyó sobre la expresión del centro blanco y la temperatura de gelatinización en los progenitores y posiblemente en las poblaciones segregantes. El medio ambiente influyó más sobre los progenitores LR5y L6850 (y sus progenies. La selección hacia centro blanco bajo parece no ser eficiente en generaciones tempranas, especialmente en el caso de L6850 e IRAT8, en contraste con la mayor eficiencia de la selección por temperatura de gelatinización (heredabilidad alta. Se encontró un alto índice de concordancia (79%, entre la escala 0 a 5 utilizada para calificación subjetiva de centro blanco y el área del grano afectada por centro blanco, (lectura hecha en esteroscopio con micrómetro. A research work was undertaken at the Centro International de Agricultura Tropical (CIAT, during 1989-91. There was no maternal effect on the express ion of white center and gelatinization temperature but rather different degrees of dominance, the order of dominance was Colombia 1 > IR5 = L6850 > LRAT8; the in vitro culture influenced the express ion of white belly and the gelatinization temperature in the parents and possibly in their progenies; the influence of the environment was greater on IRAT8 and L6850 (and its progenies; selection for low white belly seemed to be not efficient in early generations; but selection for the desired gelatinization temperature is more efficient (high heritability. With the F3 samples, a subjective evaluation was carried out (zero: endosperm without white belly, and five: completely chalky, There was found a high index of concordance (79 3. NUEVAS VÍAS DE PERMEABILIDAD Y REGULACIÓN DEL pH INTRACELULAR COMO POSIBLES BLANCOS TERAPÉUTICOS EN Plasmodium falciparum Directory of Open Access Journals (Sweden) MARY LUZ LÓPEZ 2008-05-01 Full Text Available Actualmente, existe una necesidad sentida para el desarrollo de nuevos fármacos antimaláricos o de compuestos conocidos dirigidos contra blancos terapéuticos diferentes a los afectados por los medicamentos usuales. Son diversos los blancos que pueden ser aprovechados en Plasmodium, y la alteración de parámetros fisiológicos como el pH y el transporte de solutos pueden explicar la muerte del parásito cuando se usan compuestos antiplasmodiales, lo que representa una opción para el desarrollo de nuevas alternativas antiparasitarias. El propósito de esta revisión es por tanto, proporcionar una visión general de los efectos causados por esteroides, discutiendo el caso específico de los esteroides antiplasmodiales aislados de Solanum nudum y revisar dos procesos fisiológicos importantes en el parásito como posibles blancos terapéuticos, la modificación de permeabilidad del eritrocito infectado y el mantenimiento del pH intracelular de Plasmodium. 4. Application of a new methodology on the multicycle analysis for the Laguna Verde NPP en Mexico International Nuclear Information System (INIS) Cortes C, Carlos C. 1997-01-01 This paper describes the improvements done in the physical and economic methodologies on the multicycle analysis for the Boiling Water Reactors of the Laguna Verde NPP in Mexico, based on commercial codes and in-house developed computational tools. With these changes in our methodology, three feasible scenarios are generated for the operation of Laguna Verde Nuclear Power Plant Unit 2 at 12, 18 and 24 months. The physical economic results obtained are showed. Further, the effect of the replacement power is included in the economic evaluation. (author). 11 refs., 3 figs., 7 tabs 5. Atmospheric emissions control at ENELVENs Ramon Laguna thermal power plant; Control de emisiones a la atmosfera en la central termoelectrica Ramon Laguna de ENELVEN Energy Technology Data Exchange (ETDEWEB) Rincon Rincon, Edis Rafael [Empresa de Servicio Electrico (ENELVEN), (Venezuela) 1997-12-31 ENELVEN is an electric utility that covers the areas of generation, transmission and distribution of the Western an South coast of the Maracaibo Lake of the Zulia State, Venezuela. General aspects of the Ramon Laguna of ENELVEN fossil power plant are presented, as well as the environmental measures implanted in this power station to avoid detrimental effects on the environment that could be caused by the emission of combustion products without the appropriate control, such as particulate matter, sulfur oxides, nitrogen oxides and carbon oxides [Espanol] ENELVEN es una empresa de servicio electrico que cubre las areas de generacion, transmision y distribucion de la Costa Occidental y Sur del Lago de Maracaibo, del Estado Zulia, Venezuela. Se presentan aspectos generales de la planta termoelectrica Ramon Laguna de la empresa ENELVEN, asi como las medidas ambientales implantadas en esta central para evitar efectos adversos sobre el ambiente que pudieran producirse por la emision de productos de la combustion si no existiera el debido control, tales como: particulas, oxidos de azufre, oxidos de nitrogeno y oxidos de carbono 6. Atmospheric emissions control at ENELVENs Ramon Laguna thermal power plant; Control de emisiones a la atmosfera en la central termoelectrica Ramon Laguna de ENELVEN Energy Technology Data Exchange (ETDEWEB) Rincon Rincon, Edis Rafael [Empresa de Servicio Electrico (ENELVEN), (Venezuela) 1996-12-31 ENELVEN is an electric utility that covers the areas of generation, transmission and distribution of the Western an South coast of the Maracaibo Lake of the Zulia State, Venezuela. General aspects of the Ramon Laguna of ENELVEN fossil power plant are presented, as well as the environmental measures implanted in this power station to avoid detrimental effects on the environment that could be caused by the emission of combustion products without the appropriate control, such as particulate matter, sulfur oxides, nitrogen oxides and carbon oxides [Espanol] ENELVEN es una empresa de servicio electrico que cubre las areas de generacion, transmision y distribucion de la Costa Occidental y Sur del Lago de Maracaibo, del Estado Zulia, Venezuela. Se presentan aspectos generales de la planta termoelectrica Ramon Laguna de la empresa ENELVEN, asi como las medidas ambientales implantadas en esta central para evitar efectos adversos sobre el ambiente que pudieran producirse por la emision de productos de la combustion si no existiera el debido control, tales como: particulas, oxidos de azufre, oxidos de nitrogeno y oxidos de carbono 7. Generation of the ECP database (ECP01.DAT) of the cycle 1 of the Unit 1 of Laguna Verde with burnt of 1377 MWD/MT; Generacion de la base ECP (ECP01.DAT) del ciclo 1 de la Unidad 1 de Laguna Verde con quemado de 1377 MWD/MT Energy Technology Data Exchange (ETDEWEB) Perusquia C, R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico) 1992-10-15 In order to carrying out a comparison among the results provided by the Program of Estimate of the ECP Critical Position and the Shutdown/Startup produced in the Cycle 1 of the Unit 1 of Laguna Verde, it was generated the base of the ECP program, following the outlines settled down in the Procedure 'Generation of ECP Database for Laguna Verde' (IT.SN/DFR-074). Next the data sheets filled when being generated the ECP01.DAT database with a burnt of 1377 MWD/MT are provided. In the report IT.SN/DFR-079 'Adjustment and Preliminary Evaluation of the Predictions of Criticity of the ECP Program with Reported Data of the Cycle 1 of the Unit 1 of Laguna Verde', the results of the comparison among those estimates of the ECP program using the ECP01.DAT database with the real data of the Cycle 1 of the Unit 1 of Laguna Verde are presented. (Author) 8. Polyphenolic glycosides isolated from Pogostemon cablin (Blanco) Benth. as novel influenza neuraminidase inhibitors. Science.gov (United States) Liu, Fang; Cao, Wei; Deng, Chao; Wu, Zhaoquan; Zeng, Guangyao; Zhou, Yingjun 2016-01-01 Influenza is historically an ancient disease that causes annual epidemics and, at irregular intervals, pandemics. At present, the first-line drugs (oseltamivir and zanamivir) don't seem to be optimistic due to the spontaneously arising and spreading of oseltamivir resistance among influenza virus. Pogostemon cablin (Blanco) Benth. (P. cablin) is an important traditional Chinese medicine herb that has been widely used for treatment on common cold, nausea and fever. In our previous study, we have identified an extract derived from P. cablin as a novel selective neuraminidase (NA) inhibitor. A series of polyphenolic compounds were isolated from P. cablin for their potential ability to inhibit neuraminidase of influenza A virus. Two new octaketides (1, 2), together with other twenty compounds were isolated from P. cablin. These compounds showed better inhibitory activity against NA. The significant potent compounds of this series were compounds 2 (IC50 = 3.87 ± 0.19 μ mol/ml), 11, 12, 14, 15, 19 and 20 (IC50 was in 2.12 to 3.87 μ mol/ml), which were about fourfold to doubled less potent than zanamivir and could be used to design novel influenza NA inhibitors, especially compound 2, that exhibit increased activity based on these compounds. With the help of molecular docking, we had a preliminary understanding of the mechanism of the two new compounds (1-2)' NA inhibitory activity. Fractions 6 and polyphenolic compounds isolated from fractions 6 showed higher NA inhibition than that of the initial plant exacts. The findings of this study indicate that polyphenolic compounds and fractions 6 derived from P. cablin are potential NA inhibitors. This work is one of the evidence that P. cablin has better inhibitory activity against influenza, which not only enriches the compound library of P. cablin, but also facilitates further development and promises its therapeutic potential for the rising challenge of influenza diseases. 9. Evaluation of phytochemical and pharmacological properties of Aegiceras corniculatum Blanco (Myrsinaceae) bark OpenAIRE Bose, Utpal; Bala, Vaskor; Rahman, Ahmed A.; Shahid, Israt Z. 2010-01-01 The methanol extract of the dried barks of Aegiceras corniculatum Blanco (Myrsinaceae) was investigated for its possible antinociceptive, cytotoxic and antidiarrhoeal activities in animal models. The preliminary studies of A. corniculatum bark showed the presence of alkaloids, glycosides, steroids, flavonoids, saponins and tannins. The extract produced significant writhing inhibition in acetic acid-induced writhing in mice at the oral dose of 250 and 500 mg/kg body weight (P < 0.001) comp... 10. ESTADO TRÓFICO DE UN LAGO TROPICAL DE ALTA MONTAÑA: CASO LAGUNA DE LA COCHA Directory of Open Access Journals (Sweden) Mery Liliana López Martínez 2015-01-01 Full Text Available Este artículo presenta los resultados de una investigación realizada con el fin de determinar el estado trófico de la laguna de La Cocha, cuerpo hídrico importante en Colombia y en el mundo, que hace parte del humedal Ramsar laguna de La Cocha, ecosistema que cumple distintas funciones y alberga una gran biodiversidad que se quiere proteger. Para lograr el propósito planteado, esta investigación se realizó entre enero y septiembre de 2013, determinando el estado trófico mediante los índices de Carlson, el índice desarrollado por la OCDE (Organización para la Cooperación y el Desarrollo Económico y el índice de Carlson modificado por Toledo. Los resultados permitieron clasificar a la laguna de La Cocha como oligotrófica y ultraoligotrófica, característica típica de lagos de alta montaña con bajos procesos de contaminación de origen aloctóno y autóctono. 11. Generation of the ECP database (ECP02.DAT) at the beginning of the cycle 1 of the Unit 1 of Laguna Verde International Nuclear Information System (INIS) Perusquia C, R. 1992-10-01 In order to carrying out a comparison among the results provided for the Program of Estimate of the ECP Critical Position and the Shutdown/Startup produced in the Cycle 1 of the Unit 1 of Laguna Verde, it was generated the base of the ECP program, following the outlines settled down in the Procedure 'Generation of ECP Database for Laguna Verde' (IT.SN/DFR 074). Next the data sheets filled when being generated the ECP02.DAT database at the beginning of the cycle are provided. In the IT.SN/DFR 079 report 'Adjustment and Preliminary Evaluation of the Predictions of Criticity of the ECP Program with Reported Data of Cycle 1 of the Unit 1 of Laguna Verde, the results of the comparison among the estimates of the ECP program using the ECP02.DAT with the real data of the Cycle 1 of the Unit 1 of Laguna Verde are presented. (Author) 12. Fiebre del oro blanco: la cocaína Directory of Open Access Journals (Sweden) Iván Marín Argüello 1999-12-01 Full Text Available La planta de coca, Erythroxylon coca es cultivada en la zona occidental de América del Sur exigiendo condiciones de suelo muy particulares. La mezcla de las hojas de cocaína con sustancias químicas origina un polvo cristalino blanco, conocido comúnmente como cocaína. Al producto obtenido del tratamiento de la cocaína con solventes se le denomina crack. El consumo de cocaína, las formas de administración más diversas y el estado fisiológico logrado por los usuarios, es denominado flash 0 high Los efectos neuro-fisiológicos son muy variados, provocando sobre todo un fuerte estímulo al Sistema Nervioso Central (SNC, producto de la liberación de dopamina en las terminaciones nerviosas. 13. Reassessment of the 1892 Laguna Salada Earthquake: Fault Kinematics and Rupture Patterns Czech Academy of Sciences Publication Activity Database Rockwell, T.K.; Fletcher, J.M.; Teran, O.J.; Hernandez, A.P.; Mueller, K.J.; Salisbury, J.B.; Akciz, S.O.; Štěpančíková, Petra 2015-01-01 Roč. 105, č. 6 (2015), s. 2885-2893 ISSN 0037-1106 R&D Projects: GA MŠk LH12078 Institutional support: RVO:67985891 Keywords : paleoseismology * earthquake s * fault kinematics * Laguna Salada * Mexico Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.311, year: 2015 14. Prototype fuel fabrication for nuclear reactors of Laguna Verde International Nuclear Information System (INIS) Nocetti, C.; Torres, J.; Medrano, A. 1996-01-01 Four prototype fuel bundles for the Laguna Verde Nuclear Power Plant have been fabricated. the type of nuclear fuel produced is described and the process used is commented. As an example of the fabrication criteria adopted, the production model to determine the density of the U O 2 pellets for the different batches of ceramic powder is described. the results are evaluated using the statistical indexes C p and C pk . (author) 15. Modeling of the vapor cycle of Laguna Verde with the PEPSE code to conditions of thermal power licensed at present (2027 MWt) International Nuclear Information System (INIS) Castaneda G, M. A.; Maya G, F.; Medel C, J. E.; Cardenas J, J. B.; Cruz B, H. J.; Mercado V, J. J. 2011-11-01 By means of the use of the performance evaluation of power system efficiencies (PEPSE) code was modeled the vapor cycle of the nuclear power station of Laguna Verde to reproduce the nuclear plant behavior to conditions of thermal power, licensed at present (2027 MWt); with the purpose of having a base line before the implementation of the project of extended power increase. The model of the gauged vapor cycle to reproduce the nuclear plant conditions makes use of the PEPSE model, design case of the vapor cycle of nuclear power station of Laguna Verde, which has as main components of the model the great equipment of the vapor cycle of Laguna Verde. The design case model makes use of information about the design requirements of each equipment for theoretically calculating the electric power of exit, besides thermodynamic conditions of the vapor cycle in different points. Starting from the design model and making use of data of the vapor cycle measured in the nuclear plant; the adjustment factors were calculated for the different equipment s of the vapor cycle, to reproduce with the PEPSE model the real vapor cycle of Laguna Verde. Once characterized the model of the vapor cycle of Laguna Verde, we can realize different sensibility studies to determine the effects macros to the vapor cycle by the variation of certain key parameters. (Author) 16. Rio Blanco: nuclear operations and chimney reentry International Nuclear Information System (INIS) Woodruff, W.R.; Guido, R.S. 1975-01-01 Rio Blanco was the third experiment in the U.S. Atomic Energy Commission's Plowshare Program to develop technology to stimulate gas production from geologic formations not conducive to production by conventional means. The project was sponsored by CER Geonuclear Corporation, with the Lawrence Livermore Laboratory providing the explosives and several technical programs, such as spall measurement. Three nuclear explosives specifically designed for this application were detonated simultaneously in a minimum-diameter emplacement well using many commercially available but established-reliability components. The explosive system performed properly under extreme temperature and pressure conditions. Emplacement and stemming operations were designed with the aim of simplifying both the emplacement and reentry and fully containing the detonation products. An integrated command and control system was used with communication to all three explosives through a single coaxial cable. Reentry and the initial production testing are completed. To date 98 million standard ft 3 of chimney gas have been produced. (auth) 17. Don Quijote y Hamlet Directory of Open Access Journals (Sweden) Lúdovik B. Osterc 2002-12-01 Hamlet está loco, es un alucinado que duda de sus propios sentidos. Para él existe sólo un lado negro de la existencia, su único objeto es llegar más pronto al descubrimiento del crimen. Es egocentrico, ne cree en nada, eternamente mira en su interior, se alimenta en su desprecio de sí mismo y su sufrimiento es mucho más doloroso.que aquel de Don Quijote. Don Quijote, al contrario, cree en el hombre y su futuro. Su ideal es implantar por la fuerza, la verdad, el bien y la justicia en la tierra. Para servir a su ideal, está dispuesto a sufrir todas las posibles privaciones. Representa la fe en la verdad. Es ridículo y quizás el más cómico tipo disenado jamás por un literato. Hamlet es el hijo del rey muerte, mientras que Don Quijote está pobre. Se hace los enemigos imaginarios y lucha contra ellos, mientras que Hamlet no cree en las ilusiones (siempre duda, y tampoco no combatiría si supiera que son sinónimos de opresores. Continua con la examinación de la actitud del pueblo o sus representantes hacia Don Quijote y Hamlet y viceversa. Polonia es el representante de las multitudes populares ante Hamlet, Sancho lo es ante su senor. El primero es de sano pensamiento y al mismo tiempo un viejo charalatán. Para él Hamlet no es tanto un loco como un nino y le parece inútil para la sociedad. Sancho Pansa está persuadido de que su senor está loco, pero le está leal hasta la muerte. Don Quijote simpatiza profundamente con el pueblo, pero la única persona con la que se entiende verdaderamente es Sancho Pansa (uno no puede vivir sin otro. La actitud de Hamlet es completamente diferente, él desprecia las multitudes populares, porque también desprecia a sí mismo. social: el tedio, el hastío, el descontento de la vida, desorientación espiritual y la eclipse de la fe, miéntras que Don Quijote encarna el mundo libre, bien estar y la felicidad de los seres humanos. Por eso y porque es un ideal el más humano, generoso, noble y elevado, el autor del 18. Start-up and commercial operation of the Laguna Verde power plants, unit 1 International Nuclear Information System (INIS) Torres R, J.F. 1991-01-01 The main features of the unit 1 of the Laguna Verde Power Plant is presented as well as the phases of the start-up process. The process includes various steps and tests up to start the commercial operation. (author) 19. Ceratopetalum (Cunoniaceae) fruits of Australasian affinity from the early Eocene Laguna del Hunco flora, Patagonia, Argentina. Science.gov (United States) Gandolfo, María A; Hermsen, Elizabeth J 2017-03-01 Radially symmetrical, five-winged fossil fruits from the highly diverse early Eocene Laguna del Hunco flora of Chubut Province, Patagonia, Argentina, are named, described and illustrated. The main goals are to assess the affinities of the fossils and to place them in an evolutionary, palaeoecological and biogeographic context. Specimens of fossil fruits were collected from the Tufolitas Laguna del Hunco. They were prepared, photographed and compared with similar extant and fossil fruits using published literature. Their structure was also evaluated by comparing them with that of modern Ceratopetalum (Cunoniaceae) fruits through examination of herbarium specimens. The Laguna del Hunco fossil fruits share the diagnostic features that characterize modern and fossil Ceratopetalum (symmetry, number of fruit wings, presence of a conspicuous floral nectary and overall venation pattern). The pattern of the minor wing (sepal) veins observed in the Patagonian fossil fruits is different from that of modern and previously described fossil Ceratopetalum fruits; therefore, a new fossil species is recognized. An apomorphy (absence of petals) suggests that the fossils belong within crown-group Ceratopetalum . The Patagonian fossil fruits are the oldest known record for Ceratopetalum . Because the affinities, provenance and age of the fossils are so well established, this new Ceratopetalum fossil species is an excellent candidate for use as a calibration point in divergence dating studies of the family Cunoniaceae. It represents the only record of Ceratopetalum outside Australasia, and further corroborates the biogeographic connection between the Laguna del Hunco flora and ancient and modern floras of the Australasian region. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. 20. Proposal for implementation of alternative source term in the nuclear power plant of Laguna Verde International Nuclear Information System (INIS) Bazan L, A.; Lopez L, M.; Vargas A, A.; Cardenas J, J. B. 2009-10-01 In 2010 the nuclear power plant of Laguna Verde will implement the extended power upbeat in both units of the plant. Agree with methodology of NEDC-33004P-A, (constant pressure power up rate), and the source term of core, for accidents evaluations, were increased in proportion to the ratio of power level. This means that for the case of a design basis accident of loss of coolant an increase of power of 15% originated an increase of 15% in dose to main control room. Using the method of NEDC-33004P-A to extended power upbeat conditions was determined that the dose value to main control room is very near to regulatory limit established by SRP 6.4. By the above and in order to recover the margin, the nuclear power plant of Laguna Verde will calculate an alternative source term following the criteria established in RG 1.183 (alternative radiological source term for evaluating DBA at nuclear power reactor). This approach also have a more realistic dose value using the criterion of 10-CFR-50.67, in addition is predicted to get the benefit of additional operational flexibilities. This paper present the proposal of implementing the alternative source term in Laguna Verde. (Author) 1. May 2011 Groundwater and Surface Water Sampling at the Rio Blanco, Colorado, Site (Data Validation Package) International Nuclear Information System (INIS) 2011-01-01 Annual sampling was conducted at the Rio Blanco, Colorado, site for the Long-Term Hydrologic Monitoring Program May 16-17, 2011, to monitor groundwater and surface water for potential radionuclide contamination. Sampling and analyses were conducted as specified in Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). A duplicate sample was collected from location Johnson Artesian WL. Samples were analyzed by the U.S. Environmental Protection Agency (EPA) Radiation&Indoor Environments National Laboratory in Las Vegas, Nevada. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry, and for tritium using the conventional method. Tritium was not measured using the enrichment method because the EPA laboratory no longer offers that service. Results of this monitoring at the Rio Blanco site demonstrate that groundwater and surface water outside the boundaries have not been affected by project-related contaminants. 2. MORFOMETRÍA, HIDRODINÁMICA Y FÍSICO-QUÍMICA DEL AGUA DE LA LAGUNA DE CHAUTENGO, GUERRERO, MÉXICO Directory of Open Access Journals (Sweden) Rendón-Dircio JA 2012-02-01 Full Text Available Se realizó un estudio del comportamiento de las variables morfométricas, batimétricas, hidrodinámicas y físico-químicas de la Laguna de Chautengo, Guerrero, a partir de fotografías aéreas y trabajo de campo con muestreos bimensuales de variables morfométricas, hidrodinámicas y físico-químicas del agua. Los resultados indicaron que la laguna presentó marcadas variaciones anuales en su morfometría y batimetría. El área máxima estimada fue de 29.6 km2. La barra de la laguna es recta y está colonizada en un 36.8 % por comunidades de manglar, tiene una longitud de 10 km y una anchura media de 0.52 km. Las tres islas que presenta la laguna se ubican cerca de la desembocadura y tienen un área de 83,000, 3,680 y 61,440 m2 respectivamente. La variación vertical de la columna de agua fluctuó entre 6 y 12 cm diarios, presentándose el máximo nivel a las 18:00 y 0:00 h y el mínimo a las 6:00 h. Las corrientes presentaron un valor promedio de velocidad de 1.97 m/min. La temperatura media anual fue de 29.8 oC, con una variación entre la superficie y el fondo de 0.23 oC; la salinidad varió de 0.7 a 38 ‰; el oxígeno disuelto se registró en promedio en 4.71 mg/L, existiendo una diferencia del 8.7 % entre la superficie. La laguna presenta características de un cuerpo de agua somero y tropical en un proceso avanzado de evolución, pero con condiciones adecuadas para el desarrollo de la fauna y flora acuática. Este estudio servirá de base para el diseño de un plan de manejo sostenible de las pesquerías y acuicultura de la Laguna de Chautengo. 3. Membership, binarity, and rotation of F-G-K stars in the open cluster Blanco 1 Science.gov (United States) Mermilliod, J.-C.; Platais, I.; James, D. J.; Grenon, M.; Cargile, P. A. 2008-07-01 Context: The nearby open cluster Blanco 1 is of considerable astrophysical interest for formation and evolution studies of open clusters because it is the third highest Galactic latitude cluster known. It has been observed often, but so far no definitive and comprehensive membership determination is readily available. Aims: An observing programme was carried out to study the stellar population of Blanco 1, and especially the membership and binary frequency of the F5-K0 dwarfs. Methods: We obtained radial-velocities with the CORAVEL spectrograph in the field of Blanco 1 for a sample of 148 F-G-K candidate stars in the magnitude range 10 rate reaches 40% (27/68) if one includes the photometric binaries. The cluster mean heliocentric radial velocity is +5.53 ± 0.11 km s-1 based on the most reliable 49 members. The V sin i distribution is similar to that of the Pleiades, confirming the age similarities between the two clusters. Conclusions: This study clearly demonstrates that, in spite of the cluster's high Galactic latitude, three membership criteria - radial velocity, proper motion, and photometry - are necessary for performing a reliable membership selection. Furthermore, even with accurate and extensive data, ambiguous cases still remain. Based on observations collected with the Danish 1.54-m and the Swiss telescopes at the European Southern Observatory, La Silla, Chile, and with the old YALO 1-m telescope at the Cerro Tololo InterAmerican Observatory, Chile. Table [see full textsee full textsee full textsee full textsee full textsee full text] is also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/485/95 4. Influencia de la dispersión del flujo en la remoción de coliformes fecales en las lagunas secundarias de estabilización de Masaya Directory of Open Access Journals (Sweden) S. Gámez 2006-08-01 Full Text Available Lagunas de estabilización de aguas residuales domésticas en Nicaragua diseñadas para que el efluente no contenga un NMP de CF mayor que el indicado en el Decreto 33-95 “Normativas para el control de la contaminación proveniente de las descargas de aguas residuales domésticas, industriales y agropecuarias” no producen un efluente con esa calidad. Se realizaron estudios, para conocer el por qué de esta situación, en dos lagunas secundarias de estabilización de la ciudad de Masaya. Una laguna cuenta con pantallas deflectoras y por tanto un número de dispersión mucho menor que la segunda. Los resultados son: a La laguna secundaria con pantallas deflectoras produce un efluente con menos variaciones y menor NMPCF/100 ml; b El valor del coeficiente de extinción bacterial es menor que el reportado en la literatura; c No se encontró evidencia que este valor estuviera influido por el número de dispersión de flujo de la laguna. 5. Super compacting of drums with dry solid radioactive waste in the nuclear power plant of Laguna Verde;Super compactacion de bidones con desecho radiactivo solido seco en la central nucleo electrica Laguna Verde Energy Technology Data Exchange (ETDEWEB) Ramirez G, R.; Lara H, M. A.; Cabrera Ll, M.; Verdalet de la Torre, O., E-mail: [email protected] [Comision Federal de Electricidad, Central Nucleoelectrica de Laguna Verde, Carretera Nautla-Cardel Km. 42.5, Alto Lucero, Veracruz (Mexico) 2009-10-15 The nuclear power plant of Laguna Verde located in the Gulf of Mexico, completes in this 2009, nineteen years to produce by nuclear means 4.78% of the electric power that Mexico requires daily. During this time, the Unit 1 has generated more of 88.85 million mega watt-hour and the Unit 2 more of 69.48 million mega watt-hour with an availability average of 83.55%. Derived of their operation cycles, the nuclear power plant has generated (as any other installation of its type) radioactive wastes of low activity that at the moment are temporarily stored in the site. Due to the life cycle of the nuclear power plant, actually has become necessary to begin a project series focused to continue guaranteeing the storage of these wastes, guarantee that is a license requirement for the operation of this nuclear installation before the National Commission of Nuclear Security and Safeguards. The Federal Commission of Electricity beginning a project that allows continue guaranteeing space of sufficient storage for the wastes that the nuclear power plant of Laguna Verde could generate for the rest of its useful life, this project consisted on a process of physical volume reduction of dry solid radioactive wastes denominated super compacting, it has made possible to reduce the volume that these wastes occupy in the temporary storage noted Dry Solid Radioactive Wastes Deposit located inside the site that occupies the nuclear power plant of Laguna Verde. This work presents the super compacting results, as well as a description of the realization of this task until concluding with the super compacting of 5,854 drums with dry solid radioactive waste of low activity. We will enunciate which were the radiological controls that the Department of Radiological Protection of the nuclear power plant of Laguna Verde applied to this work that was realized for first time in Mexico and the nuclear power plant. (Author) 6. Start up and commercial operation of Laguna Verde nuclear power plant. Unit 1 International Nuclear Information System (INIS) Torres Ramirez, J.F. 1991-01-01 Prior to start up of Laguna Verde nuclear power plant preoperational tests and start tests were performed and they are described in its more eminent aspects. In relation to commercial operation of nuclear station a series of indicator were set to which allow the measurement of performance in unit 1, in areas of plant efficiency and personal safety. Antecedents. Laguna Verde station is located in Alto Lucero municipality in Veracruz state, 70 kilometers north-northeast from port of Veracruz and a 290 kilometers east-northeast from Mexico city. The station consist of two units manufactured by General Electric, with a nuclear system of vapor supply also called boiling water (BWR/5), and with a system turbine-generator manufactured by Mitsubishi. Each unit has a nominal power of 1931 MWt and a level design power of 675 Mwe and a net power of 654 Electric Megawatts 7. Analysis of internal events for the Unit 1 of the Laguna Verde Nuclear Power Station. Appendixes; Analisis de eventos internos para la Unidad 1 de la Central Nucleoelectrica de Laguna Verde. Apendices Energy Technology Data Exchange (ETDEWEB) Huerta B, A; Lopez M, R [Comision Nacional de Seguridad Nuclear y Salvaguardias, 03000 Mexico D.F. (Mexico) 1995-07-01 This volume contains the appendices for the accident sequences analysis for those internally initiated events for Laguna Verde Unit 1, Nuclear Power Plant. The appendix A presents the comments raised by the Sandia National Laboratories technical staff as a result of the review of the Internal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant. This review was performed during a joint Sandia/CNSNS multi-day meeting by the end 1992. Also included is a brief evaluation on the applicability of these comments to the present study. The appendix B presents the fault tree models printed for each of the systems included and.analyzed in the Internal Event Analysis for LVNPP. The appendice C presents the outputs of the TEMAC code, used for the cuantification of the dominant accident sequences as well as for the final core damage evaluation. (Author) 8. Safety evaluation of the Laguna Verde nuclear power plant International Nuclear Information System (INIS) Delgado G, J.L. 1991-01-01 The present work describe the licensing process for the first nuclear power plant built in Mexico, it presents the difficulties found during the several years of construction and tests until the phrase a level of safety equivalent to that of the country of origin of the nuclear steam supply system could be applicable to Laguna Verde, at least from the point of view of the mexican regulatory body, and also that this statement could be signed for the inspectors of international organizations. (author) 9. Modernization of the turbo in the Laguna Verde Nuclear Power Plant International Nuclear Information System (INIS) Liebana, B.; Merino, A.; Cobos, A.; Gonzalez, J. J. 2010-01-01 The power increase of the Laguna Verde Nuclear Power Plant is a project for the rehabilitation and modernization of the turbo and associated equipment to get an increase of its power and of its service life. The project scope includes the design, the engineering, the equipment supply, the installation, the testing and the commissioning. This paper describes the first phase of the project. 10. Don Quixote og romangenren DEFF Research Database (Denmark) Kluge, Sofie Through the centuries Cervantes' Don Quixote (1605/1615) has delighted readers, inspired artists, and helped form our perception of early modern Spain. Moreover, it has played a major part in the development and theoretisation of one of the modern world's most central artistic forms: the novel. Don... 11. The continuous improvement system of nuclear power plant of Laguna Verde; El sistema de mejora continua de la central nucleoelectrica Laguna Verde Energy Technology Data Exchange (ETDEWEB) Rivera C, A. [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Km. 42.5 Cardel-Nautla, Veracruz (Mexico)], e-mail: [email protected] 2009-10-15 This paper describes the continuous improvement system of nuclear power plant of Laguna Verde and the achievements in implementing the same and additionally two study cases are presents. In February 2009 is noteworthy because the World Association of Nuclear Operators we identified as a learning organization, qualification which shows that the continuous improvement system has matured, and this system will expose as I get to learn to capitalize on our own experiences and external experiences diffused by the nuclear industry. In 2007 the management of nuclear power plants integrates its improvement systems and calls it continuous improvement system and is presented in the same extensive report that won the National Quality Award. This system is made up of 5 subsystems operating individually and are also related 1) human performance; 2) referential comparison or benchmarking; 3) self-assessment; 4) corrective action and 5) external operating experience. Five subsystems that plan, generate, capture, manage, communicate and protect the knowledge generated during the processes execution of nuclear power plant of Laguna Verde, as well as from external sources. The target set in 2007 was to increase the intellectual capital to always give response to meeting the security requirements, but creating a higher value to quality, customer, environment protection and society. In brief each of them, highlighting the objective, expectations management, implementation and some benefits. At the end they will describe two study cases selected to illustrate these cases as the organization learns by their continuous improvement system. (Author) 12. Waterbirds and human-related threats to their conservation in Laguna Cuyutlán, Colima, México Directory of Open Access Journals (Sweden) Eric Mellink 2009-06-01 Full Text Available Laguna Cuyutlán, the only large wetland in a span of 1 150 km along the Pacific coast of México, has been neglected as to its importance for waterbird conservation. At least 25 waterbird species nest there, with some of their colonies being very relevant, and at least 61 waterbird species use the lagoon during their nonbreeding season. This lagoon has been subject to several structural modifications, including levees and artificial channels which connect it to the sea, while water supply from continental sources has diminished, although its role has not been assessed yet. Salt extraction and artisanal fishery, the main economic activities, do not seem to pose a threat to waterbirds. Among potential threats to this acquatic ecosystem, are the raw sewage discharges that exist near urban areas, and pesticides from the surrounding agricultural lands might reach the lagoon. Seemingly, the most serious threat comes from waterway development in connection with a re-gasification plant to be built, and planned future port expansion, which could potentially increase water levels and alter important habitats for nesting and foraging. We recommend that: the area be declared an Important Bird Area; the development of the re-gasification plant and future port includes a levee to prevent alterations in water level in the remaining sections of the lagoon; supply of exogenous chemicals and waste products be prevented and monitored; alleged benefits from water interchange between the lagoon and the sea through artificial channels should be re-evaluated; and the role of fresh water supplies to the lagoon should be paid attention to. Rev. Biol. Trop. 57 (1-2: 1-12. Epub 2009 June 30.Laguna Cuyutlán, el único humedal grande a lo largo de 1 150 km del Pacífico mexicano, no ha sido considerado un ecosistema natural importante para la conservación de aves acuáticas. Cuando menos 25 especies de aves acuáticas anidan ahí, y al menos 61 especies de aves acu 13. Correlation and Fishers’ Perception in Selected Sites in Laguna de Bay, Luzon Island, Philippines Directory of Open Access Journals (Sweden) Arthur J. Lagbas 2017-01-01 Full Text Available White goby (Glossogobius giuris Hamilton 1822 is an omnivorous, native fish species which can be found in Laguna de Bay and its tributaries, and in other bodies of water in the Philippines. Deteriorating water quality, unsustainable fishing practices, aquaculture and predation by introduced invasive species are threatening the population of white goby and other native fish species in Laguna de Bay. This study was conducted to correlate select physico-chemical parameters of lake water and zooplankton abundance, and to assess white goby population based on fishers’ perception. Water samples were collected in three sites in June, September and December 2014. Twenty one zooplankton species belonging to 12 families were identified. The most abundant and frequently encountered zooplankton species is Eurytemora affinis Poppe 1880. Zooplanktons were most abundant in June and lowest in September. Key informant interviews with local fishers revealed that white goby population was abundant in April to August while catch report showed that fish catch is abundant in June and least during December. The fish abundance in April to June could be attributed to high productivity especially in summer season. The fishers perceived that the population of white goby was declining mainly due to water pollution, aquaculture, and predation by invasive alien species. A multi-stakeholder sustainable watershed management should be adapted to improve the water quality and extinction of native fish species in Laguna de Bay. 14. Determination of heavy metals and other elements by Neutron Activation Analysis in sediment cores of laguna Mar Chiquita (Cordoba, Argentina) International Nuclear Information System (INIS) Larizzatti, Flavio Eduardo 2001-01-01 Laguna Mar Chiquita is one of the largest water bodies of South America. It is a big lake of saline waters, and its geographic localization is SOMS' S, 62 deg 30' W, about 150 km Northwest of Cordoba, Argentina. Due to its large variability of hydrological budget, surface and water levels produced periods of low stands (LLP) and high stands (HLP). This fluctuation of water level also produces substantial changes in the water salinity. The principal tributary of the Laguna Mar Chiquita is Dulce River and also receives water from two other rivers: Suquia and Xanaes. The Suquia River drains in a small satellite lake, the Laguna del Plata. The purpose of the present work was to investigate the sediment composition of the Laguna Mar Chiquita (2 sediment cores) and del Plata (one sediment core) by using Neutron Activation Analysis (NAA) technique. The three 60 cm long sediment cores, sliced each 2 cm, were analyzed and 26 elements were determined (As, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Lu, Na, Nd, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, U, Yb, Zn e Zr). Other complementary techniques were utilized: macro elements (Al, Ca, Fe, K, Mg, Mn, Na, P, Si, Ti) were determined by X-ray fluorescence, and the mineralogical composition of the sediments was determined by X-ray diffraction. The results obtained did not show any indication of anthropic contribution in the sediment composition, and concentration of the majority of the elements analyzed is uniform along the entire profile of the analyzed core. Statistical analysis of elemental concentrations (Cluster Analysis) reflects that in Laguna del Plata the fine fractions of the sediments is dominated by detrital minerals, while in the Laguna Mar Chiquita, the neo formed minerals are the principal components. In both lakes, it was possible to identify compositional variations in the sediment segments, which may correspond to temporal fluctuations in the sedimentation conditions. The statistical analysis associated to sedimentation 15. History and current safety measures at Laguna Palcacocha, Huaraz, Peru Science.gov (United States) Salazar Checa, César; Cochachin, Alejo; Frey, Holger; Huggel, Christian; Portocarrero, César 2017-04-01 Laguna Palcacocha is a large glacier lake in the Cordillera Blanca, Peru, located in the Quillcay catchment, above the city of Huaraz, the local capital. On 13 December 1941, the moraine dam lake collapsed, probably after having been impacted by a large ice avalanche, and triggered a major outburst flood. This GLOF destroyed about a third of the city of Huaraz, causing about 2,000 casualties and is therefore one of the deadliest glacier lake outbursts known in history. In 1974, the Glaciology Unit of Peru, responsible for the studying, monitoring and mitigation works related to glacier hazards installed a reinforcement of the natural moraine dam of the newly filled Laguna Palcacocha, with an artificial drainage channel at 7 m below the crest of the reinforced dam. At that time, the lake had an area of 66,800 m2 and a volume of 0.5 x 106 m3. During the past decades, in the course of continued glacier retreat, Laguna Palcacocha has undergone an extreme growth. In February 2016, the lake had an area of 514,000 m2 (7.7 times the area of 1974) and a volume of more than 17 x 106 m3 (more than 34 times the volume of 1974). At the same time, the city of Huaraz, located 20 km downstream of the lake, grew significantly after its almost complete destruction by the 1970 earthquake. Today, about 120,000 people are living in the city. Due to the persisting possibility for large ice avalanches directly above the Palcacocha lake, this constitutes a high-risk situation, requiring new hazard and risk mitigation measures. As an immediate temporal measure, in order to bridge the time until the realization of a more permanent measure, a syphoning system has been installed in 2011, using about ten 700-m pipes with a 10-inch (25.4 cm) diameter. The aim of this syphoning attempt is to lower the lake level by about 7 m, and therefore reduce the lake volume on the one hand, and also reach a higher dam freeboard. However, the system is less effective than assumed, currently the lake level 16. Fuel failure at the Laguna Verde unit 1- during Cycle 4 International Nuclear Information System (INIS) Espinosa Vega, Juan Manuel 1996-01-01 The present work describes the event occurred at the Laguna Verde nuclear power plants Unit 1 during its fourth cycle ensembles; the first failure, by means of a test of power suppression, and the second one, during the sipping accomplished in the four refuelling of the unit. Also it describes the re-evaluation of the event accomplished by the licenser, the manufacturer and the Mexican agency 17. Generation of the ECP database (ECP01.DAT) of the cycle 1 of the Unit 1 of Laguna Verde with burnt of 1377 MWD/MT International Nuclear Information System (INIS) Perusquia C, R. 1992-10-01 In order to carrying out a comparison among the results provided by the Program of Estimate of the ECP Critical Position and the Shutdown/Startup produced in the Cycle 1 of the Unit 1 of Laguna Verde, it was generated the base of the ECP program, following the outlines settled down in the Procedure 'Generation of ECP Database for Laguna Verde' (IT.SN/DFR-074). Next the data sheets filled when being generated the ECP01.DAT database with a burnt of 1377 MWD/MT are provided. In the report IT.SN/DFR-079 'Adjustment and Preliminary Evaluation of the Predictions of Criticity of the ECP Program with Reported Data of the Cycle 1 of the Unit 1 of Laguna Verde', the results of the comparison among those estimates of the ECP program using the ECP01.DAT database with the real data of the Cycle 1 of the Unit 1 of Laguna Verde are presented. (Author) 18. A pollen diagram from “Laguna de la Herrera” (Sabana de Bogota) NARCIS (Netherlands) Hammen, van der T.; Gonzalez, E. 1965-01-01 The Laguna de La Herrera (alt. ca 2550 m) is a lake situated on the western border of the Sabana de Bogotá, near Mosquera (dept. of Cundinamarca, Colombia) (fig. 2). This part of the Sabana has a relatively dry climate (appr. 600—700 mm rainfall), as it lies in the rain-shadow of the hills that 19. Radionuclide Migration at the Rio Blanco Site, A Nuclear-stimulated Low-permeability Natural Gas Reservoir Energy Technology Data Exchange (ETDEWEB) Clay A. Cooper; Ming Ye; Jenny Chapman; Craig Shirley 2005-10-01 The U.S. Department of Energy and its predecessor agencies conducted a program in the 1960s and 1970s that evaluated technology for the nuclear stimulation of low-permeability gas reservoirs. The third and final project in the program, Project Rio Blanco, was conducted in Rio Blanco County, in northwestern Colorado. In this experiment, three 33-kiloton nuclear explosives were simultaneously detonated in a single emplacement well in the Mesaverde Group and Fort Union Formation, at depths of 1,780, 1,899, and 2,039 m below land surface on May 17, 1973. The objective of this work is to estimate lateral distances that tritium released from the detonations may have traveled in the subsurface and evaluate the possible effect of postulated natural-gas development on radionuclide migration. Other radionuclides were considered in the analysis, but the majority occur in relatively immobile forms (such as nuclear melt glass). Of the radionuclides present in the gas phase, tritium dominates in terms of quantity of radioactivity in the long term and contribution to possible whole body exposure. One simulation is performed for {sup 85}Kr, the second most abundant gaseous radionuclide produced after tritium. 20. Tres patos ocasionales en la Sabana de Bogotá y la Laguna de Fúquene Directory of Open Access Journals (Sweden) Borrero José Ignacio 1944-12-01 Full Text Available Agradezco al Dr. Armando Dugand la ayuda que se sirvió dispensarme para la presentación de este articulo. Creo de interes, para principiar, hacer una breve descripción de las condiciones de la Sabana de Bogotá y la Laguna de Fúquene, como localidades de paso o estacionamiento temporal para las especies migratorias de Anátidas. La Sabana de Bogotá ocupa una vasta altiplanicie de unos 2000 kilómetros cuadrados a 2600 mts. de altura media, rodeada de montanas o cerros en toda su extensión y cruzada por pequeños rios. El rio Bogotá, que la atraviesa, forma en sus riberas y en casi toda su extensión grandes lagunas y pantanos apropiados para la llegada de los patos y otras aves acuáticas que anualmente vienen del Norte y otras regiones. 1. Rio Blanco, Colorado, Long-Term Hydrologic Monitoring Program Sampling and Analysis Results for 2009 International Nuclear Information System (INIS) 2009-01-01 The U.S. Department of Energy (DOE) Office of Legacy Management conducted annual sampling at the Rio Blanco, Colorado, Site, for the Long-Term Hydrologic Monitoring Program (LTHMP) on May 13 and 14, 2009. Samples were analyzed by the U.S. Environmental Protection Agency (EPA) Radiation&Indoor Environments National Laboratory in Las Vegas, Nevada. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectroscopy and tritium using the conventional and enriched methods. 2. Cuantificación de los aportes hídricos subterráneos a la laguna de Santa Olalla a partir de balances hídricos diarios (Parque Nacional de Doñana, Huelva) OpenAIRE Rodríguez Rodríguez, Miguel; Fernández Ayuso, Ana; Moral Martos, Francisco 2017-01-01 En este estudio se ha realizado un balance hídrico a escala diaria en la laguna de Santa Olalla, una de las pocas lagunas de hidroperiodo permanente del Parque Nacional de Doñana. El balance volumétrico se ha realizado determinando las salidas y entradas a partir de los datos meteorológicos de estaciones cercanas y de los registros trihorarios del nivel del agua de la laguna. Los resultados indican unos aportes por escorrentía, mayoritariamente subterránea, a la laguna de 0,39 hm3 desde en... 3. Radiocarbon dating of the Peruvian Chachapoya/Inca site at the Laguna de los Condores International Nuclear Information System (INIS) Wild, E.M.; Kutschera, W.; Seidler, H.; Steier, P.; Guillen, S. 2005-01-01 Full text: An archaeological site with several funerary houses built in the cliffs of the Laguna de los Condores by the Chachapoya people was discovered in 1997 in the cloud forest at a sea level of 2500 m in the Amazonas/San Martin area in Peru. The Chachapoya people and their culture is not fully understood until now and some myths entwine around the origin of that South American ancient civilisation. The Chachapoya are described as people of warriors, which were finally subdued by the Incas. A typical characteristic of their culture is the special burial of their dead in funeral bundles containing the remains of the bodies. At the Laguna de los Condores more that 200 mummies have been found and transferred to Leymebamba. During the rescue work of the mummies, which were in danger to be destroyed by looters, it turned out that two different burial patterns could be detected. It is assumed, that after conquering of the Chachapoyas, the Inca people took over also the burial cliff houses and used it for their own burials. The Incas themselves were subdued by the Spanish Conquistadors in 1532 AD. In order to shed light on the transition from the Chachapoya to the Inka dominance, which is connected with the history of the Laguna de los Condores funeral site, a multidisciplinary project between archaeologists, anthropologists and physicists has been started. VERA contributes to this project with several radiocarbon dates of archaeological objects and of the mummies from this Chachapoya/Inca site. (author) 4. Seismic qualification tests of fans of the NPP of Laguna Verde U-1 and U-2; Pruebas de calificacion sismica de ventiladores de la Central Laguna Verde U1 and U2 Energy Technology Data Exchange (ETDEWEB) Jarvio C, G.; Garcia H, E. E.; Arguelles F, R.; Vela H, A. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Naranjo U, J. L., E-mail: [email protected] [Comision Federal de Electricidad, Gerencia de Centrales Nucleoelectricas, Subgerencia de Ingenieria, Carretera Veracruz-Medellin Km 7.5, Dos Bocas, Veracruz (Mexico) 2013-10-15 This work presents the results of the seismic qualification tests applied to the fans that will be installed in the control panels of the three divisions of the diesel generators of the nuclear power plant (NPP) of Laguna Verde, Unit-1 and Unit-2. This seismic qualification process of the fans was carried out using two specimens that were tested in the seismic table (vibrating) of the Engineering Institute of Universidad Nacional Autonoma de Mexico (UNAM), in accordance with the requirements of the standard IEEE 344-1975, to satisfy the established requirements of seismic qualification in the technical specifications and normative documents required by the nuclear standards, in order to demonstrate its application in the diesel generators Divisions I, II and III of the NPP. The seismic qualification tests were developed on specimens that were retired of the NPP of Laguna Verde recently with a service life of 7.75 years. (Author) 5. DON-induced changes in bone homeostasis in mink dams Directory of Open Access Journals (Sweden) Tomaszewska Ewa 2017-09-01 Full Text Available Introduction: The aim of the study was to investigate the mechanical and geometric properties as well as bone tissue and mineral density of long bones in mink dams exposed to deoxynivalenol (DON since one day after mating, throughout gestation (ca. 46 d and lactation to pelt harvesting. Material and Methods: Thirty clinically healthy multiparous minks (Neovison vison of the standard dark brown type were used. After the mating, the minks were randomly assigned into two equal groups: nontreated control group and DON group fed wheat contaminated naturally with DON at a concentration of 1.1 mg·kg-1 of feed. Results: The final body weight and weight and length of the femur did not differ between the groups. However, DON contamination decreased mechanical endurance of the femur. Furthermore, DON reduced the mean relative wall thickness and vertical wall thickness of the femur, while vertical cortical index, midshaft volume, and cross-sectional moment of inertia increased. Finally, DON contamination did not alter bone tissue density, bone mineral density, or bone mineral content, but decreased the values of all investigated structural and material properties. Conclusion: DON at applied concentration probably intensified the process of endosteal resorption, which was the main reason for bone wall thinning and the weakening of the whole bone. 6. Cantharellus gallaecicus (Blanco-Dios Olariaga, comb. & stat. nov (Cantharellaceae Directory of Open Access Journals (Sweden) Olariaga, Ibai 2007-12-01 Full Text Available Cantharellus gallaecicus comb. & stat. nov. is proposed, after the examination of its holotype and additional material. Based on the characters observed in all the studied material (i.e., thinwalled hyphae of the pileipelis, minute basidiomata with white to grey pileus, and surface that turns yellow when bruised it is considered that C. gallaecicus is more closely related to C. romagnesianus than to C. cibarius.Se propone Cantharellus gallaecicus comb. & stat. nov. tras revisar su holótipo y material adicional disponible. Dado que todo el material examinado posee hifas del pileipelis de pared delgada, basidiomas pequeños con píleo de blanco a gris, y superficie que vira a amarillo al roce, se considera que C. gallaecicus es una especie más estrechamente relacionada con C. romagnesianus que con C. cibarius. 7. DCVD Measurements at the Laguna Verde NPP International Nuclear Information System (INIS) Chen, J.D.; Gerwing, A.F.; Kosierb, R.; Vones, J.; Broodryck, A. 2006-01-01 A new digital Cerenkov viewing device (DCVD) with high ultraviolet light sensitivity has been developed. Field measurements on BWR spent fuel at Laguna Verde Nuclear Power Plant Unit 2 resulted in new Cerenkov information on GE9 and GE12 spent fuel assemblies. Off-alignment measurements show: quantitative differences in the degree of light collimation from between the fuel rods; lack of light collimation from water rods; and decreased light collimation from partial length rod positions. Hidden rods could also be detected in off-angle views. The results indicate that it may be possible to detect missing partial-length fuel rods in GE12 fuel assemblies. The new DCVD was able to verify low burnup, long-cooled, natural uranium GE6 fuel assemblies 8. DCVD Measurements at the Laguna Verde NPP Energy Technology Data Exchange (ETDEWEB) Chen, J.D.; Gerwing, A.F. [Channel Systems Inc., Pinawa MA (Canada); Kosierb, R. [Canadian Nuclear Safety Commission, Ottawa, ON (Canada); Vones, J.; Broodryck, A. [International Atomic Energy Agency, Vienna (Austria) 2006-12-30 A new digital Cerenkov viewing device (DCVD) with high ultraviolet light sensitivity has been developed. Field measurements on BWR spent fuel at Laguna Verde Nuclear Power Plant Unit 2 resulted in new Cerenkov information on GE9 and GE12 spent fuel assemblies. Off-alignment measurements show: quantitative differences in the degree of light collimation from between the fuel rods; lack of light collimation from water rods; and decreased light collimation from partial length rod positions. Hidden rods could also be detected in off-angle views. The results indicate that it may be possible to detect missing partial-length fuel rods in GE12 fuel assemblies. The new DCVD was able to verify low burnup, long-cooled, natural uranium GE6 fuel assemblies. 9. PROPAGACIÓN DE Tabebuia Donnell-Smithii Rose (GUAYACÁN BLANCO UTILIZANDO HORMONAS DE ENRAIZAMIENTO Directory of Open Access Journals (Sweden) Mercedes Susana Carranza Patiño 2013-02-01 Full Text Available Resumen La amplia distribución y abundancia natural de Tabebuia donnell-smithii (guayacán blanco se ha visto reducida por la tala excesiva de los árboles, lo que ha ocasionado la desaparición de genotipos valiosos así como disminución de las poblaciones naturales, existiendo además carencia de alternativas de producción de plantas a gran escala. Se hace por tanto necesario orientar la investigación a establecer una técnica para la propagación vegetativa de guayacán blanco utilizando fitorreguladores. La metodología se basó en el uso de las hormonas de enraizamiento ácido naftalenacético (ANA y ácido indolbutírico (AIB, en concentraciones de 0, 1,500 y 2,000 mg kg-1 en sustratos turba y arena. Las yemas apicales fueron colocadas en una cámara húmeda en condiciones de invernadero. Se aplicó un Diseño Completamente al Azar (DCA en un arreglo factorial 2 sustratos x 3 dosis de hormona ANA x 3 dosis de hormona AIB, con cuatro repeticiones y cuatro unidades de observación. A los 45 días se evaluó el porcentaje de sobrevivencia y el enraizamiento, el número de raíces, la longitud de la raíz mayor, el número de brotes, la longitud de brotes, y el vigor. Los resultados no mostraron diferencias significativas entre los distintos tratamientos para todas las variables, sin embargo para el efecto simple e interacciones se observó diferencias para las variables evaluadas, siendo el mejor sustrato turba y las concentraciones óptimas de auxinas de 0 a 1,500 mg Kg-1. Se concluye que el guayacán blanco es una especie de fácil enraizamiento, ya que con y sin la aplicación de hormonas enraizadoras en el sustrato turba y arena se logró la obtención de clones, disminuyendo el tiempo de obtención de nuevas plantas. 10. Evaluación del proceso y la eficiencia de remoción de la materia orgánica en las lagunas de estabilización del municipio de La Ceja, Antioquia, Colombia Directory of Open Access Journals (Sweden) MEJÍA RUIZ ROBERTO 2010-05-01 Full Text Available En esta investigación, se estudió la condición ambiental y el funcionamiento de las lagunas de estabilización para el tratamiento de las aguas residuales del municipio de La Ceja, Antioquia. Este sistema ha presentado deficiencias en su operación, reflejadas en problemas organolépticos, hidráulicos y metabólicos. El sistema de lagunas del municipio de La Ceja está conformado por dos lagunas anaerobias y una laguna facultativa, que reciben las aguas residuales domésticas provenientes de un alcantarillado combinado. En los años 2003 y 2004, se realizaron mediciones de variables físicas, químicas y biológicas, incluyendo tres muestreos generales. El sistema funcionó deficientemente debido a problemas hidráulicos. La deficiencia del sistema estuvo acompañada de una baja remoción de nutrientes disueltos en la laguna facultativa asociada a un pobre desarrollo de la comunidad de microorganismos. El sistema presentó una remoción de carga orgánica del 75 %, relacionada principalmente con la sedimentación en las lagunas anaerobias. 11. Variación temporal y espacial de aves playeras en la laguna Barra de Navidad, Jalisco, en tres temporadas no reproductivas OpenAIRE Salvador Hernández; Sergio Serrano; Xóchitl A. Hernández; María Isabel Robles 2012-01-01 Hay un escaso conocimiento de las aves playeras en los humedales costeros de Jalisco, y en particular en la laguna Barra de Navidad. El presente trabajo contribuye al conocimiento de este grupo de aves y describe su distribución temporal y espacial en la laguna Barra de Navidad durante tres temporadas no reproductivas (1999-2000, 2006-2007 y 2008-2009). Se realizaron censos mensuales de noviembre-abril en las tres temporadas con el fin de registrar todas las especies de aves playeras. Se iden... 12. Expectations for the Laguna foil implosion experiments International Nuclear Information System (INIS) Greene, A.; Brownell, J.; Caird, R.; Goforth, J.; Price, R.; Trainor, J. 1987-01-01 Building on the results achieved in the Pioneer shot series, the Los Alamos Trailmaster project is embarking on the Laguna foil implosion experiments. In this series a Mark-IX helical generator will be coupled to an explosively formed fuse opening switch, a surface-tracking closing switch, and a vacuum power flow and load chamber. In this paper the system design will be discussed and results from zero-, one-, and two-dimensional MHD simulations will be presented. It is anticipated that the generator will provide more than 10 MA of which ∼5.5 MA will be switched to the 5-cm-radius, 2-cm-high, 250-nm-thick aluminum foil load. This should give rise to a 1 μs implosion with more than 100 kJ of kinetic energy 13. Antitubercular constituents from Premna odorata Blanco. Science.gov (United States) Lirio, Stephen B; Macabeo, Allan Patrick G; Paragas, Erickson M; Knorn, Matthias; Kohls, Paul; Franzblau, Scott G; Wang, Yuehong; Aguinaldo, Ma Alicia M 2014-06-11 Premna odorata Blanco (Lamiaceae) is a medicinal plant traditionally used in Albay Province, in southeastern Luzon, Philippines to treat tuberculosis. This study aimed to determine the antitubercular property of the crude extract and sub-extracts of the leaves, and to isolate the bioactive principles from the active fractions. Through extraction, solvent polarity-based fractionation and silica gel chromatography purification of the DCM sub-extract, compound mixtures from the bioactive fractions were isolated and screened for their in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv using the colorimetric Microplate Alamar Blue assay (MABA). The crude methanolic extract and sub-extracts showed poor inhibitory activity against Mycobacterium tuberculosis H37Rv (MIC≥128µg/mL). However, increased inhibitory potency was observed for fractions eluted from the DCM sub-extract (MIC=54 to 120µg/mL). Further purification of the most active fraction (MIC=54µg/mL) led to the isolation of a 1-heneicosyl formate (1), 4:1 mixture of β-sitosterol (2), stigmasterol (3) and diosmetin (4), which were identified through GC-MS analysis (with dereplication) and NMR experiments. The MIC of compound 1 was 8µg/mL. The results of this study provide scientific basis for the traditional use of Premna odorata as treatment for tuberculosis. Copyright © 2014. Published by Elsevier Ireland Ltd. 14. Fitness for Kids Who Don't Like Sports Science.gov (United States) ... Español Fitness for Kids Who Don't Like Sports KidsHealth / For Parents / Fitness for Kids Who Don' ... look for something new. Still Shopping for a Sport Some kids haven't found the right sport. ... 15. Ikaite precipitation in a lacustrine environment - implications for palaeoclimatic studies using carbonates from Laguna Potrok Aike (Patagonia, Argentina) Science.gov (United States) Oehlerich, Markus; Mayr, Christoph; Griesshaber, Erika; Lücke, Andreas; Oeckler, Oliver M.; Ohlendorf, Christian; Schmahl, Wolfgang W.; Zolitschka, Bernd 2013-07-01 The monoclinic mineral ikaite (CaCO3 · 6H2O) and its pseudomorphs are potentially important archives for palaeoenvironmental reconstructions. Natural ikaite occurs in a small temperature range near freezing point and is reported mainly from marine and only rarely from continental aquatic environments. Ikaite transforms to more stable anhydrous forms of CaCO3 after an increase in temperature or when exposed to atmospheric conditions. The knowledge about conditions for natural ikaite formation, its stable isotope fractionation factors and isotopic changes during transformation to calcite is very restricted. Here, for the first time, primary precipitation of idiomorphic ikaite and its calcite pseudomorphs are reported from a subsaline lake, Laguna Potrok Aike, in southern Argentina. The calculated stable oxygen isotope fractionation factor between lake water and ikaite-derived calcite (αPAI = 1.0324 at a temperature of 4.1 °C) is close to but differs from that of primarily inorganically precipitated calcite. Pseudomorphs after ikaite rapidly disintegrate into calcite powder that is indistinguishable from μm-sized calcite crystals in the sediment record of Laguna Potrok Aike suggesting an ikaite origin of sedimentary calcites. Therefore, the Holocene carbonates of Laguna Potrok Aike have the potential to serve as a recorder of past hydrological variation. 16. Aproximación ecotoxicológica a la contaminación por metales pesados en la laguna costera del Mar Menor OpenAIRE Marín Guirao, Lázaro 2007-01-01 El objetivo de la Tesis es obtener una visión de la situación actual de la laguna costera del Mar Menor en relación con la contaminación por metales pesados procedentes de actividades mineras mediante el empleo de herramientas ecotoxicológicas. Comienza con el estudio de la entrada de residuos mineros en el ecosistema, su distribución en las aguas de la laguna así como los efectos tóxicos asociados. Continua valorando la biodisponibilidad de los metales contenidos en los sedimentos lagunares ... 17. Analysis of internal events for the Unit 1 of the Laguna Verde Nuclear Power Station. Appendixes International Nuclear Information System (INIS) Huerta B, A.; Lopez M, R. 1995-01-01 This volume contains the appendices for the accident sequences analysis for those internally initiated events for Laguna Verde Unit 1, Nuclear Power Plant. The appendix A presents the comments raised by the Sandia National Laboratories technical staff as a result of the review of the Internal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant. This review was performed during a joint Sandia/CNSNS multi-day meeting by the end 1992. Also included is a brief evaluation on the applicability of these comments to the present study. The appendix B presents the fault tree models printed for each of the systems included and.analyzed in the Internal Event Analysis for LVNPP. The appendice C presents the outputs of the TEMAC code, used for the cuantification of the dominant accident sequences as well as for the final core damage evaluation. (Author) 18. Analysis of internal events for the Unit 1 of the Laguna Verde Nuclear Power Station. Appendixes International Nuclear Information System (INIS) Huerta B, A.; Lopez M, R. 1995-01-01 This volume contains the appendices for the accident sequences analysis for those internally initiated events for Laguna Verde Unit 1, Nuclear Power Plant. The appendix A presents the comments raised by the Sandia National Laboratories technical staff as a result of the review of the Internal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant. This review was performed during a joint Sandia/CNSNS multi-day meeting by the end 1992. Also included is a brief evaluation on the applicability of these comments to the present study. The appendix B presents the fault tree models printed for each of the systems included and analyzed in the Internal Event Analysis for LVNPP. The appendice C presents the outputs of the TEMAC code, used for the cuantification of the dominant accident sequences as well as for the final core damage evaluation. (Author) 19. Introduction of fuel GE14 in the nuclear power plant of Laguna Verde for the extended increase of power; Introduccion del combustible GE14 en la central nuclear Laguna Verde para el aumento de potencia extendido Energy Technology Data Exchange (ETDEWEB) Hernandez M, N.; Vargas A, A. F.; Cardenas J, J. B.; Contreras C, P. [CFE, Central Nuclear Laguna Verde, Subgerencia de Ingenieria, Carretera Veracruz-Medellin Km. 7.5 (Mexico)]. e-mail: [email protected] 2008-07-01 The project of extended increase of power responds to a necessity of electrical energy in the country, increasing the thermal exit of the reactors of the nuclear power plant of Laguna Verde of 2027 MWt to 2317 MWt. In order to support this transition, changes will make in the configuration of the reactor core and in the operation strategies of the cycle, also they will take initiatives to optimize the economy in fuel cycle. At present in both reactors of the nuclear plant of Laguna Verde fuel GE12 is used. The fuel GE14 presents displays with respect to the GE12, some improvements in the mechanical design and consequently in its performance generally. Between these improvements we can mention: 1. Spacers of high performance. 2. Shielding with barrier. 3. Filter for sweepings {sup d}ebris{sup a}nd 4. Fuel rods of minor partial length. The management of nuclear power plants has decided to introduce the use of fuel GE14 in Laguna Verde in the reload 14 for Unit 1 and of the reload 10 for Unit 2. The process of new introduction fuel GE14 consists of two stages, first consists on subjecting the one new design of fuel to the regulator organism in the USA: Nuclear Regulatory Commission, in Mexico the design must be analyzed and authorized by the National Commission of Nuclear Safety and Safeguards, for its approval of generic form, by means of the demonstration of the fulfillment with the amendment 22 of GESTAR II, the second stage includes the specific analyses of plant to justify the use of the new fuel design in a reload core. The nuclear plant of Laguna Verde would use some of the results of the security analyses that have been realized for the project of extended increase of power with fuel GE14, to document the specific analyses of plant with the new fuel design. The result of the analyses indicates that the reload lots are increased of 116-120 assemblies in present conditions (2027 MWt) to 140-148 assemblies in conditions of extended increase of power (2317 MWt 20. Don Quichotte, un don quichotte ? Déprogrammation d’un stéréotype Directory of Open Access Journals (Sweden) Marta Cuenca-Godbert 2009-12-01 Full Text Available En réaction à la publication de la suite apocryphe de Don Quichotte de la Manche, Cervantès utilise dans sa seconde partie les ressorts narratifs de la stéréotypie littéraire pour montrer à quel point son personnage diffère de ce qu'en a fait Alonso Fernández de Avellaneda, continuateur peu respectueux de sa personne et de son personnage. Le refus de voir en don Quichotte un simple stéréotype du chevalier errant chimérique est particulièrement manifeste dans la série d'aventures se déroulant au château des ducs, où don Quichotte, par sa renommée littéraire littéralement reconnue, est traité en chevalier par des personnages manipulateurs de situations, qui visent à produire chez lui des réactions programmées pour s’en amuser. Il apparaît alors que le simple agrégat d'ingrédients propres au stéréotype littéraire chevaleresque finit par ne pas produire l'issue escomptée.En la Segunda parte del Quijote, Cervantes reacciona ante la publicación de la de Alonso Fernández de Avellaneda, continuador poco respetuoso con la persona del autor primigenio y su personaje. Recurriendo a los procedimientos narrativos de la estereotipia literaria deja bien claro qué diferente resulta ser el personaje original respecto al del continuador. La negativa de ver a don Quijote como un mero estereotipo del caballero andante loco se pone particularmente de manifiesto en la serie de aventuras que transcurren en el palacio de los duques. Allí, los personajes reconocen literalmente la fama literaria de don Quijote. Generan, desde situaciones ficticias, tipos de tratamiento que se dispensarían a un verdadero caballero andante. Como resultado, se desencadena una serie de reacciones programadas con las que pretenden divertirse. Sin embargo, queda claro que la mera acumulación de ingredientes propios del estereotipo literario caballeresco no produce el resultado esperado. 1. Microbial Detoxification of Deoxynivalenol (DON), Assessed via a Lemna minor L. Bioassay, through Biotransformation to 3-epi-DON and 3-epi-DOM-1. Science.gov (United States) Vanhoutte, Ilse; De Mets, Laura; De Boevre, Marthe; Uka, Valdet; Di Mavungu, José Diana; De Saeger, Sarah; De Gelder, Leen; Audenaert, Kris 2017-02-13 Mycotoxins are toxic metabolites produced by fungi. To mitigate mycotoxins in food or feed, biotransformation is an emerging technology in which microorganisms degrade toxins into non-toxic metabolites. To monitor deoxynivalenol (DON) biotransformation, analytical tools such as ELISA and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) are typically used. However, these techniques do not give a decisive answer about the remaining toxicity of possible biotransformation products. Hence, a bioassay using Lemna minor L. was developed. A dose-response analysis revealed significant inhibition in the growth of L. minor exposed to DON concentrations of 0.25 mg/L and higher. Concentrations above 1 mg/L were lethal for the plant. This bioassay is far more sensitive than previously described systems. The bioassay was implemented to screen microbial enrichment cultures, originating from rumen fluid, soil, digestate and activated sludge, on their biotransformation and detoxification capability of DON. The enrichment cultures originating from soil and activated sludge were capable of detoxifying and degrading 5 and 50 mg/L DON. In addition, the metabolites 3-epi-DON and the epimer of de-epoxy-DON (3-epi-DOM-1) were found as biotransformation products of both consortia. Our work provides a new valuable tool to screen microbial cultures for their detoxification capacity. 2. Microbial Detoxification of Deoxynivalenol (DON, Assessed via a Lemna minor L. Bioassay, through Biotransformation to 3-epi-DON and 3-epi-DOM-1 Directory of Open Access Journals (Sweden) Ilse Vanhoutte 2017-02-01 Full Text Available Mycotoxins are toxic metabolites produced by fungi. To mitigate mycotoxins in food or feed, biotransformation is an emerging technology in which microorganisms degrade toxins into non-toxic metabolites. To monitor deoxynivalenol (DON biotransformation, analytical tools such as ELISA and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS are typically used. However, these techniques do not give a decisive answer about the remaining toxicity of possible biotransformation products. Hence, a bioassay using Lemna minor L. was developed. A dose–response analysis revealed significant inhibition in the growth of L. minor exposed to DON concentrations of 0.25 mg/L and higher. Concentrations above 1 mg/L were lethal for the plant. This bioassay is far more sensitive than previously described systems. The bioassay was implemented to screen microbial enrichment cultures, originating from rumen fluid, soil, digestate and activated sludge, on their biotransformation and detoxification capability of DON. The enrichment cultures originating from soil and activated sludge were capable of detoxifying and degrading 5 and 50 mg/L DON. In addition, the metabolites 3-epi-DON and the epimer of de-epoxy-DON (3-epi-DOM-1 were found as biotransformation products of both consortia. Our work provides a new valuable tool to screen microbial cultures for their detoxification capacity. 3. Blood Pressure Medicines Donât Work If People Donât Take Them PSA (:60) Centers for Disease Control (CDC) Podcasts This 60 second public service announcement is based on the September 2016 CDC Vital Signs report. Blood pressure medicines donât work if people donât take them. Learn how health care systems can work with patients to make taking medicines easier. 4. Simulation of overpressure events with a Laguna Verde model for the RELAP code to conditions of extended power up rate; Simulacion de eventos de sobrepresion con un modelo de Laguna Verde para el codigo RELAP a condiciones de aumento de potencia extendido Energy Technology Data Exchange (ETDEWEB) Rodriguez H, A.; Araiza M, E.; Fuentes M, L.; Ortiz V, J., E-mail: [email protected] [ININ, Departamento de Sistemas Nucleares, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico) 2012-10-15 In this work the main results of the simulation of overpressure events are presented using a model of the nuclear power plant of Laguna Verde developed for the RELAP/SCDAPSIM code. As starting point we have the conformation of a Laguna Verde model that represents a stationary state to similar conditions to the operation of the power station with Extended Power Up rate (EPU). The transitory of simulated pressure are compared with those documented in the Final Safety Analysis Report of Laguna Verde (FSAR). The results of the turbine shot transitory with and without by-pass of the main turbine are showed, and the event of closes of all the valves of main vapor isolation. A preliminary simulation was made and with base in the results some adjustments were made for the operation with EPU, taking into account the Operation Technical Specifications of the power station. The results of the final simulations were compared and analyzed with the content in the FSAR. The response of the power station to the transitory, reflected in the model for RELAP, was satisfactory. Finally, comments about the improvement of the model are included, for example, the response time of the protection and mitigation systems of the power station. (Author) 5. Components production and assemble of the irradiation capsule of the Surveillance Program of Materials of the nuclear power plant of Laguna Verde International Nuclear Information System (INIS) Medrano, A. 2009-01-01 To predict the effects of the neutrons radiation and the thermal environment about the mechanical properties of the reactor vessel materials of the nuclear power plant of Laguna Verde, a surveillance program is implemented according to the outlines settled by Astm E185-02 -Standard practice for design of surveillance programs for light-water moderated nuclear power reactor vessels-. This program includes the installation of three irradiation capsules of similar materials to those of the reactor vessels, these samples are test tubes for mechanical practices of impact and tension. In the National Institute of Nuclear Research and due to the infrastructure as well as of the actual human resources of the Pilot Plant of Nuclear Fuel Assembles Production it was possible to realize the materials rebuilding extracted in 2005 of Unit 2 of nuclear power plant of Laguna Verde as well as the production, assemble and reassignment of the irradiation capsule made in 2006. At the present time the surveillance materials extracted in 2008 of Unit 1 of the nuclear power plant of Laguna Verde are reconstituting and the components are manufactured for the assembles of the irradiation capsule that will be reinstalled in the reactor vessel in 2010. The purpose of the present work is to describe the necessary components as well as its disposition during the assembles of the irradiation capsule for the surveillance program of the reactors vessel of the nuclear power plant of Laguna Verde. (Author) 6. Mineral resource potential map of the Blanco Mountain and Black Canyon roadless areas, Inyo and Mono counties, California Science.gov (United States) Diggles, Michael F.; Blakely, Richard J.; Rains, Richard L.; Schmauch, Steven W. 1983-01-01 On the basis of geologic, geochemical, and geophysical investigations and a survey of mines and prospects, the mineral resource potential for gold, silver, lead, zinc, tungsten, and barite of the Blanco Mountain and Black Canyon Roadless Areas is judged to be low to moderate, except for one local area that has high potential for gold and tungsten resources. 7. Pluralidad y lagunas jurídicas en ecoleyes relacionadas con áreas naturales protegidas de competencia estatal en México Directory of Open Access Journals (Sweden) Jesús Ignacio Castro Salazar 2018-02-01 Full Text Available En este artículo se diserta sobre la pluralidad y las lagunas jurídicas en las áreas naturales protegidas en México, por considerarlas un instrumento de conservación clave para cientos de especies y ecosistemas. El estudio se realizó a escala nacional con base en la legislación vigente hasta finales de 2015, con el objetivo de identificar las lagunas legales relacionadas con dichas áreas; primero se presenta el estado del arte y el enfoque teórico-conceptual que guió al estudio, y luego se describe la metodología empleada, basada principalmente en análisis de contenido. También se muestran los resultados y las discusiones sobre la pluralidad de las leyes en la materia, y además las lagunas existentes en ellas. Entre los primeros destaca que, a pesar de que en casi todos los estados hay áreas naturales protegidas, la mayoría no cuenta con leyes para su regulación, y también sobresale que muchas autorizan el autoconsumo, aunque no lo definen. 8. Rio Blanco massive hydraulic fracture: project definition International Nuclear Information System (INIS) 1976-01-01 A recent Federal Power Commission feasibility study assessed the possibility of economically producing gas from three Rocky Mountain basins. These basins have potentially productive horizons 2,000 to 4,000 feet thick containing an estimated total of 600 trillion cubic feet of gas in place. However, the producing sands are of such low permeability and heterogeneity that conventional methods have failed to develop these basins economically. The Natural Gas Technology Task Force, responsible for preparing the referenced feasibility study, determined that, if effective well stimulation methods for these basins can be developed, it might be possible to recover 40 to 50 percent of the gas in place. The Task Force pointed out two possible underground fracturing methods: Nuclear explosive fracturing, and massive hydraulic fracturing. They argued that once technical viability has been demonstrated, and with adequate economic incentives, there should be no reason why one or even both of these approaches could not be employed, thus making a major contribution toward correcting the energy deficiency of the Nation. A joint Government-industry demonstration program has been proposed to test the relative effectiveness of massive hydraulic fracturing of the same formation and producing horizons that were stimulated by the Rio Blanco nuclear project 9. Internal event analysis for Laguna Verde Unit 1 Nuclear Power Plant. Accident sequence quantification and results International Nuclear Information System (INIS) Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R. 1994-01-01 The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the I nternal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant, CNSNS-TR 004, in five volumes. The reports are organized as follows: CNSNS-TR 004 Volume 1: Introduction and Methodology. CNSNS-TR4 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR 004 Volume 3: System Analysis. CNSNS-TR 004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR 005 Volume 5: Appendices A, B and C. This volume presents the development of the dependent failure analysis, the treatment of the support system dependencies, the identification of the shared-components dependencies, and the treatment of the common cause failure. It is also presented the identification of the main human actions considered along with the possible recovery actions included. The development of the data base and the assumptions and limitations in the data base are also described in this volume. The accident sequences quantification process and the resolution of the core vulnerable sequences are presented. In this volume, the source and treatment of uncertainties associated with failure rates, component unavailabilities, initiating event frequencies, and human error probabilities are also presented. Finally, the main results and conclusions for the Internal Event Analysis for Laguna Verde Nuclear Power Plant are presented. The total core damage frequency calculated is 9.03x 10-5 per year for internal events. The most dominant accident sequences found are the transients involving the loss of offsite power, the station blackout accidents, and the anticipated transients without SCRAM (ATWS). (Author) 10. DAYA ANTIBAKTERI EKSTRAK ETANOL DAUN SENGGANI (Melastoma affine D. Don Directory of Open Access Journals (Sweden) Ika Trisharyanti Dian Kusumowati 2014-08-01 Full Text Available Melastoma affine D. Don had some activities such as anthelmintic, antibacteria, antiinfiammation, antifungal, and antitumor. The aims of this research was determine antibacteria activity of ethanolic extract of Melastoma affine D. Don. The antimicrobial activity was tested by solid dilution method to get Minimum Inhibition Concentration (MIC. The compounds in Melastoma affine D. Don was analyzed by tube test method and Thin Layer Chromatography (TLC with chloroform : methanol : formic acid (8,5:1,5:0,5 as mobile phase and silica gel GF254 as stationary phase. The result showed ethanolic extract of Melastoma affine D. Don contains alkaloid, polyphenol, fiavonoid, saponin, and essential oil. The MIC of Senggani against Staphylococcus aureus was 2% and 3% against Escherichia coli and the extract could not inhibit Staphylococcus aureus and Escherichia coli multiresistant until concentration 7% extract ethanol. Keywords: Melastoma affine D. Don, Staphylococcus aureus, Escherichia coli 11. Patrones de variación espacial y temporal de los macroinvertebrados acuáticos en la Laguna de Tecocomulco, Hidalgo (México Directory of Open Access Journals (Sweden) Axel Eduardo Rico-Sánchez 2014-04-01 Full Text Available La Laguna de Tecocomulco (Hidalgo es un relicto de los antiguos Lagos del Anáhuac con suma importancia para la conservación de aves acuáticas. No obstante, se desconoce su composición de macroinvertebrados. En el presente estudio se analizaron las variaciones espaciales y temporales de los macroinvertebrados acuáticos de la laguna. Se realizaron cuatro campañas de monitoreo (lluvias y estiaje. Se estudiaron seis sitios (litorales y en interior de la laguna, se registraron factores ambientales, se determinaron parámetros de calidad del agua y se recolectaron macroinvertebrados acuáticos. Se obtuvo la riqueza de familias y se calculó su Índice de Valor de Importancia. Se realizaron análisis multivariados de ordenación por componentes principales (ACP con base en sus características físicas y químicas y de similitud entre sitios y familias con los índices de Jaccard y Bray-Curtis. Tambien se hizo un análisis de correspondencias canónicas (ACC de factores ambientales y macroinvertebrados acuáticos y macrófitas. El ACP mostró la variación estacional, con el período cálido (mayo y agosto y el periodo frío (noviembre y enero mostrando altos valores de conductividad, alcalinidad, dureza, sulfatos y macronutrientes (N y P. Se encontraron 26 familias de macroinvertebrados, con la máxima riqueza en agosto. El análisis de similitud de Jaccard diferenció los sitios litorales por su mayor riqueza de familias de la zona limnética, mismos que presentan diferencias en la composición de macrófitas. El estudio revela que la Laguna de Tecocomulco tiene variaciones espaciales y temporales relacionadas tanto con factores ambientales como bióticos con la presencia de grupos dominantes. En ese sentido, y considerando su diversidad de macroinvertebrados, la Laguna de Tecocomulco debe ser sujeta a un plan de conservación y manejo. 12. Rock Magnetic Properties of Laguna Carmen (Tierra del Fuego, Argentina): Implications for Paleomagnetic Reconstruction Science.gov (United States) Gogorza, C. G.; Orgeira, M. J.; Ponce, F.; Fernández, M.; Laprida, C.; Coronato, A. 2013-05-01 We report preliminary results obtained from a multi-proxy analysis including paleomagnetic and rock-magnetic studies of two sediment cores of Laguna Carmen (53°40'60" S 68°19'0" W, ~83m asl) in the semiarid steppe in northern Tierra del Fuego island, Southernmost Patagonia, Argentina. Two short cores (115 cm) were sampled using a Livingstone piston corer during the 2011 southern fall. Sediments are massive green clays (115 to 70 cm depth) with irregularly spaced thin sandy strata and lens. Massive yellow clay with thin sandy strata continues up to 30 cm depth; from here up to 10 cm yellow massive clays domain. The topmost 10 cm are mixed yellow and green clays with fine sand. Measurements of intensity and directions of Natural Remanent Magnetization (NRM), magnetic susceptibility, isothermal remanent magnetization, saturation isothermal remanent magnetization (SIRM), back field and anhysteretic remanent magnetization at 100 mT (ARM100mT) were performed and several associated parameters calculated (ARM100mT/k and SIRM/ ARM100mT). Also, as a first estimate of relative magnetic grain-size variations, the median destructive field of the NRM (MDFNRM), was determined. Additionally, we present results of magnetic parameters measured with vibrating sample magnetometer (VSM). The stability of the NRM was analyzed by alternating field demagnetization. The magnetic properties have shown variable values, showing changes in both grain size and concentration of magnetic minerals. It was found that the main carrier of remanence is magnetite with the presence of hematite in very low percentages. This is the first paleomagnetic study performed in lakes located in the northern, semiarid fuegian steppe, where humid-dry cycles have been interpreted all along the Holocene from an aeolian paleosoil sequence (Orgeira et el, 2012). Comparison between paleomagnetic records of Laguna Carmen and results obtained in earlier studies carried out at Laguna Potrok Aike (Gogorza et al., 2012 13. Participation of the ININ in the external radiological emergency plan of the Laguna Verde power plant; Participacion del ININ en el plan de emergencia radiologica externo de la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Martinez S, R; Cervini L, A [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico) 1991-07-01 The planning of performances in radiological emergencies, with the object of reducing the consequences as much as possible on the population to accidental liberations of radioactive material coming from Nuclear power plant, it has been of main interest in the nuclear community in the world. In Mexico it has not been the exception, since with the setting in march of the Laguna Verde nuclear power plant exists an executive program of planning for emergencies that it outlines the activities to follow trending to mitigate the consequences that are derived of this emergency. As integral part of this program this the External Plan of Radiological Emergency (PERE) that covers the emergencies that could leave the frontiers of the Laguna Verde power plant. In the PERE it settles down the planning, address and control of the preparation activities, response and recovery in emergencies, as well as the organization and coordination of the institutions that participate. The National Institute of Nuclear Research (ININ), like integral part of these institutions in the PERE, has an infrastructure that it allows to participate in the plan in a direct way in the activities of 'Control of the radiological exhibition the response personnel and control of water and foods' and of support way and consultant ship in the activities of 'Monitoring, Classification and decontamination of having evaluated' and 'Specialized medical radiological attention'. At the moment the ININ has a radiological mobile unit and this conditioning a second mobile unit to carry out part of the activities before mentioned; also accounts with 48 properly qualified people that directly intervene in the plan. In order to guarantee an adequate response in the PERE an organization it has been structured like that of the annex as for the personnel, transport, team, procedures and communication system, with the objective always of guaranteeing the security and the population's health in emergency situations in the 14. Geological setting and paleomagnetism of the Eocene red beds of Laguna Brava Formation (Quebrada Santo Domingo, northwestern Argentina) Science.gov (United States) Vizán, H.; Geuna, S.; Melchor, R.; Bellosi, E. S.; Lagorio, S. L.; Vásquez, C.; Japas, M. S.; Ré, G.; Do Campo, M. 2013-01-01 The red bed succession cropping out in the Quebrada Santo Domingo in northwestern Argentina had been for long considered as Upper Triassic-Lower Jurassic in age based on weak radiometric and paleontological evidence. Preliminary paleomagnetic data confirmed the age and opened questions about the nature of fossil footprints with avian features discovered in the section. Recently the stratigraphic scheme was reviewed with the identification of previously unrecognized discontinuities, and a radiometric dating obtained in a tuff, indicated an Eocene age for the Laguna Brava Formation and the fossil bird footprints, much younger than the previously assigned. We present a detailed paleomagnetic study interpreted within a regional tectonic and stratigraphic framework, looking for an explanation for the misinterpretation of the preliminary paleomagnetic data. The characteristic remanent magnetizations pass a tilt test and a reversal test. The main magnetic carrier is interpreted to be low Ti titanomagnetites and to a lesser extent hematite. The characteristic remanent magnetization would be essentially detrital. The obtained paleomagnetic pole (PP) for the Laguna Brava Formation has the following geographic coordinates and statistical parameters: N = 29, Lon. = 184.5° E, Lat. = 75.0° S, A95 = 5.6° and K = 23.7. When this PP is compared with another one with similar age obtained in an undeformed area, a declination anomaly is recognized. This anomaly can be interpreted as Laguna Brava Formation belonging to a structural block that rotated about 16° clockwise along a vertical axis after about 34 Ma. This block rotation is consistent with the regional tectonic framework, and would have caused the fortuitous coincidence of the PP with Early Jurassic poles. According to the interpreted magnetostratigraphic correlation, the Laguna Brava Formation would have been deposited during the Late Eocene with a mean sedimentation rate of about 1.4 cm per thousand years, probably in 15. The continuous improvement system of nuclear power plant of Laguna Verde International Nuclear Information System (INIS) Rivera C, A. 2009-10-01 This paper describes the continuous improvement system of nuclear power plant of Laguna Verde and the achievements in implementing the same and additionally two study cases are presents. In February 2009 is noteworthy because the World Association of Nuclear Operators we identified as a learning organization, qualification which shows that the continuous improvement system has matured, and this system will expose as I get to learn to capitalize on our own experiences and external experiences diffused by the nuclear industry. In 2007 the management of nuclear power plants integrates its improvement systems and calls it continuous improvement system and is presented in the same extensive report that won the National Quality Award. This system is made up of 5 subsystems operating individually and are also related 1) human performance; 2) referential comparison or benchmarking; 3) self-assessment; 4) corrective action and 5) external operating experience. Five subsystems that plan, generate, capture, manage, communicate and protect the knowledge generated during the processes execution of nuclear power plant of Laguna Verde, as well as from external sources. The target set in 2007 was to increase the intellectual capital to always give response to meeting the security requirements, but creating a higher value to quality, customer, environment protection and society. In brief each of them, highlighting the objective, expectations management, implementation and some benefits. At the end they will describe two study cases selected to illustrate these cases as the organization learns by their continuous improvement system. (Author) 16. Evaluación microbiológica y sensorial de fermentados de pozol blanco, con cacao (Theobroma cacao y coco (Cocos nucifera Directory of Open Access Journals (Sweden) Román Jiménez Vera 2010-07-01 Full Text Available El pozol es una bebida de maíz que se consume en el sureste de México y en algunos países de Centroamérica. Se puede consumir recién elaborado o fermentado. Tradicionalmente se consume solo (pozol blanco, aunque también es común agregarle cacao o coco. En este trabajo se evaluaron cambios microbiológicos durante la fermentación natural a temperatura ambiental, de tres tipos de pozol: blanco, con cacao y coco. La concentración de bacterias coliformes disminuyó a partir del tercer día de fermentación y a los 12 días se obtuvo una concentración de 2,20 log UFC/g. En las bacterias lácticas se observó el mayor crecimiento; ellas alcanzaron una concentración de 8,00 log UFC/g a los 3 días de fermentación que se mantuvo durante los 9 días siguientes. Se realizaron pruebas de nivel de agrado y preferencia con 31 jueces consumidores. La adición de ingredientes como el cacao o el coco no mejoraron el nivel de agrado entre los consumidores evaluados (p > 0,05. El pozol blanco y fresco fue el preferido (32 %. En el futuro, estos resultados pueden ser utilizados para clasificar al pozol como una bebida funcional, debido a la presencia de bacterias lácticas en concentración similar a la encontrada en el yogur. 17. Textural and geochemical features of freshwater microbialites from Laguna Bacalar, Quintana Roo, Mexico OpenAIRE Castro-Contreras, Set I.; Gingras, Murray K.; Pecoits, Ernesto; Aubet, Natalie R.; Petrash, Daniel; Castro-Contreras, Saulo M.; Dick, Gregory; Planavsky, Noah J.; Konhauser, Kurt O. 2014-01-01 Microbialites provide some of the oldest direct evidence of life on Earth. They reached their peak during the Proterozoic and declined afterward. Their decline has been attributed to grazing and/or burrowing by metazoans, to changes in ocean chemistry, or to competition with other calcifying organisms. The freshwater microbialites at Laguna Bacalar (Mexico) provide an opportunity to better understand microbialite growth in terms of interaction between grazing organisms versus calcium carb... 18. Seismic qualification tests of fans of the NPP of Laguna Verde U-1 and U-2 International Nuclear Information System (INIS) Jarvio C, G.; Garcia H, E. E.; Arguelles F, R.; Vela H, A.; Naranjo U, J. L. 2013-10-01 This work presents the results of the seismic qualification tests applied to the fans that will be installed in the control panels of the three divisions of the diesel generators of the nuclear power plant (NPP) of Laguna Verde, Unit-1 and Unit-2. This seismic qualification process of the fans was carried out using two specimens that were tested in the seismic table (vibrating) of the Engineering Institute of Universidad Nacional Autonoma de Mexico (UNAM), in accordance with the requirements of the standard IEEE 344-1975, to satisfy the established requirements of seismic qualification in the technical specifications and normative documents required by the nuclear standards, in order to demonstrate its application in the diesel generators Divisions I, II and III of the NPP. The seismic qualification tests were developed on specimens that were retired of the NPP of Laguna Verde recently with a service life of 7.75 years. (Author) 19. Internal event analysis for Laguna Verde Unit 1 Nuclear Power Plant. Accident sequence quantification and results; Analisis de eventos internos para la Unidad 1 de la Central Nucleoelectrica de Laguna Verde. Cuantificacion de secuencias de accidente y resultados Energy Technology Data Exchange (ETDEWEB) Huerta B, A; Aguilar T, O; Nunez C, A; Lopez M, R [Comision Nacional de Seguridad Nuclear y Salvaguardias, 03000 Mexico D.F. (Mexico) 1994-07-01 The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the {sup I}nternal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant, CNSNS-TR 004, in five volumes. The reports are organized as follows: CNSNS-TR 004 Volume 1: Introduction and Methodology. CNSNS-TR4 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR 004 Volume 3: System Analysis. CNSNS-TR 004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR 005 Volume 5: Appendices A, B and C. This volume presents the development of the dependent failure analysis, the treatment of the support system dependencies, the identification of the shared-components dependencies, and the treatment of the common cause failure. It is also presented the identification of the main human actions considered along with the possible recovery actions included. The development of the data base and the assumptions and limitations in the data base are also described in this volume. The accident sequences quantification process and the resolution of the core vulnerable sequences are presented. In this volume, the source and treatment of uncertainties associated with failure rates, component unavailabilities, initiating event frequencies, and human error probabilities are also presented. Finally, the main results and conclusions for the Internal Event Analysis for Laguna Verde Nuclear Power Plant are presented. The total core damage frequency calculated is 9.03x 10-5 per year for internal events. The most dominant accident sequences found are the transients involving the loss of offsite power, the station blackout accidents, and the anticipated transients without SCRAM (ATWS). (Author) 20. The President's pleasant surprise: how LGBT advocates ended Don't Ask, Don't Tell. Science.gov (United States) Frank, Nathaniel 2013-01-01 This study assesses the role of LGBT advocates in repealing the military's Don't Ask, Don't Tell policy in the U.S. Congress. It draws on the author's direct involvement with that effort as well as personal interviews and media evidence to consider the contributions of the Obama Administration, members of Congress, the media, and individuals and pressure groups in the repeal process. It argues that repeal succeeded not because of the effective implementation of a White House plan but because the pressure of LGBT advocates ultimately shattered several key obstacles including inadequate messaging and dysfunction and inertia among both politicians and interest groups in Washington. The article offers insight into the role of public pressure in forwarding social change. 1. Simulation of overpressure events with a Laguna Verde model for the RELAP code to conditions of extended power up rate International Nuclear Information System (INIS) Rodriguez H, A.; Araiza M, E.; Fuentes M, L.; Ortiz V, J. 2012-10-01 In this work the main results of the simulation of overpressure events are presented using a model of the nuclear power plant of Laguna Verde developed for the RELAP/SCDAPSIM code. As starting point we have the conformation of a Laguna Verde model that represents a stationary state to similar conditions to the operation of the power station with Extended Power Up rate (EPU). The transitory of simulated pressure are compared with those documented in the Final Safety Analysis Report of Laguna Verde (FSAR). The results of the turbine shot transitory with and without by-pass of the main turbine are showed, and the event of closes of all the valves of main vapor isolation. A preliminary simulation was made and with base in the results some adjustments were made for the operation with EPU, taking into account the Operation Technical Specifications of the power station. The results of the final simulations were compared and analyzed with the content in the FSAR. The response of the power station to the transitory, reflected in the model for RELAP, was satisfactory. Finally, comments about the improvement of the model are included, for example, the response time of the protection and mitigation systems of the power station. (Author) 2. Composición y abundancia del zooplancton en la laguna El Morro, Isla de Margarita, Venezuela Directory of Open Access Journals (Sweden) William Villalba 2017-12-01 Full Text Available Se analizó la composición y abundancia del zooplancton de la laguna El Morro en la isla de Margarita, Venezuela, durante el periodo de surgencia (marzo-mayo 2011 y de relajación (junio-agosto 2011. Las muestras fueron recolectadas en 6 estaciones de las diferentes zonas de la laguna. Se realizaron calados con una red de plancton de 333 µm durante 10 minutos. Se midió in situ la temperatura, salinidad y oxígeno disuelto, además de nutrientes. Se registraron valores medios de temperatura de 29.7 ºC, salinidad de 36 ups, oxígeno disuelto de 5.9 mg.L-1. La concentración de nutrientes fue baja (medias de 0.12; 0.04; 0.03 mg.L-1 para nitrato, nitrito y fosfato, respectivamente. Se detectaron diferencias significativas temporales con mayores registros en la temporada de relajación, mientras que espacialmente no mostró diferencias, a pesar que en las estaciones internas (Est. 4,5,6 se obtuvo mayor abundancia. Se identificaron quince grupos zooplanctónicos, determinándose nueve especies del grupo Copepoda, dos de Cladocera, una de Decapoda, Tunicada y Rotifera y diferentes formas larvarias de distintos taxa. Las larvas de crustáceos presentaron la abundancia media y relativa más alta (47738 ind.m-3 y 46.83%, respectivamente, seguido del copépodo Oithona nana (31740 ind.m-3 y 25.94%, respectivamente y Paracalanus quasimodo (12958 ind.m-3 y 8.47%, respectivamente. Esta laguna involucra la estacionalidad surgencia-relajación como un efecto importante en la distribución y abundancia del zooplancton. 3. On Both Sides of the Atlantic: Re-Visioning Don Juan and Don Quixote in Modern Literature and Film OpenAIRE Perez, Karen Patricia 2013-01-01 The study analyzes contemporary literature and film based on two of the most universal characters in Spanish literature, Don Juan and Don Quixote, in both Spain and Hispanic America. Although both characters have undergone re-visioning from work to work through the centuries, it is the aim of this work to present the most salient characteristics of both archetypes in modern times only. The focus of this study is on works by well-known writers from Hispanic America and contemporary writers in ... 4. Bioavailability of dissolved organic nitrogen (DON) in wastewaters from animal feedlots and storage lagoons Science.gov (United States) Dissolved organic nitrogen (DON) transport from animal agriculture to surface waters can lead to eutrophication and dissolved oxygen depletion. Biodegradable DON (BDON) is a portion of DON that is mineralized by bacteria while bioavailable DON (ABDON) is utilized by bacteria and/or algae. This stu... 5. Validation of the thermal balance of Laguna Verde turbine under conditions of extended power increase; Validacion del balance termico de turbina de Laguna Verde en condiciones de aumento de potencia extendido Energy Technology Data Exchange (ETDEWEB) Castaneda G, M. A.; Cruz B, H. J.; Mercado V, J. J.; Cardenas J, J. B.; Garcia de la C, F. M., E-mail: [email protected] [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km 42.5, Alto Lucero, Veracruz (Mexico) 2012-10-15 The present work is a continuation of the task: Modeling of the vapor cycle of Laguna Verde with the PEPSE code to conditions of thermal power licensed at present (2027 MWt) in which the modeling of the vapor cycle of the nuclear power plant of Laguna Verde was realized with PEPSE code (Performance Evaluation of Power System Efficiencies). Once reached the conditions of nominal operation of extended power increase, operating both units to 2371 MWt; after the tests phase of starting-up and operation is necessary to carry out a verification of the proposed design of the vapor cycle for the new operation conditions. All this, having in consideration that the vapor cycle designer only knows the detail of the prospective performance of the main turbine, for all the other components (for example pumps, heat inter changers, valves, reactor, humidity separators and re-heaters, condensers, etc.) makes generic suppositions based on engineering judgment. This way carries out the calculations of thermal balance to determine the guaranteed gross power. The purpose of the present work is to comment the detail of the validation carried out of the specific thermal balance (thermal kit) of the nuclear power plant, making use of the design characteristics of the different components that conform the vapor cycle. (Author) 6. Mimesis in Don Quixote Directory of Open Access Journals (Sweden) Giselle von der Walde 2006-04-01 Full Text Available Resumen:Frente a argumentos tomados de las poéticas neoaristotélicas que esgrime el canónigo para condenar los libros de caballerías, don Quijote pretende mostrar con su propio ejemplo, que ese tipo de lecturas no llevan a la locura ni al abandono de sí mismo, sino que, por el contrario, sacan lo mejor de la naturaleza de un individuo y lo hacen mejor persona. Este es el único tipo de imitación que Platón acepta en la República, pues más que un remedo o una suplantación, implica emulación. Este escrito se propone mirar, a partir del diálogo con el canónigo de Toledo (I, 49-50, cómo en sus conductas miméticas desde el comienzo de la obra, don Quijote entiende la imitación como emulación; en consecuencia se intenta demostrar que el efecto de la literatura en el caballero manchego parece ser el tipo de mimesis que Platón acepta en el libro III de la República.Abstract:Don Quijote demonstrates with the example of his own life the error made by the Canon of Toledo when the latter uses the arguments of the neo-Aristotelian poets to condemn the novels of chivalric romance. Quijote tries to show that reading the chivalric romances leads to neither madness nor the abandonment of the self, but, on the contrary, brings out the best in a person’s nature, and makes one a better person. This is the only type of imitation that Plato accepts in the Republic, because, unlike the mere copying of a person, or the substitution of one person for another, it implies a type of emulation. Starting with the dialogue of the Canon of Toledo (I, 49-50, this paper shows how, in his mimetic behavior, Don Quijote understands imitation as emulation. As a result, the paper shows that the effect of literature on the gentleman from La Mancha is the type of mimesis of which Plato approves in book III of the Republic. 7. Tourism in Laguna (SC: Impacts and attitude. Directory of Open Access Journals (Sweden) Susana de Araujo Gastal 2012-04-01 Full Text Available The places by the sea, as spaces of tourism and second homes, suffer the impacts from the activity. The local population attitude, seeing these places as bonuses or otherwise, as a burden, contributes to the viability of tourism in the locality. This article aims to present a research, methodologically related to attitude construct of social psychology, conducted in Laguna, Santa Catarina, Brazil to evaluate the relationship between the community and the different impacts caused by tourism,. Data collection, using an instrument originally proposed and validated by Molero and Cuadrado (2006, allowed the analysis to forward the position of residents on the effects of tourism in the place, evaluating eight impacts factors: environmental; delinquency; everyday life; perceived importance of tourism; public services and infrastructure; intercultural; employment; and values. The results indicate that most impacts are positive on younger residents, and in the environmental, crime and social values the impact is indifferent. 8. Will 3552 Don Quixote escape from the Solar System? Directory of Open Access Journals (Sweden) Suryadi Siregar 2011-05-01 Full Text Available Asteroid 1983 SA, well known as 3552 Don Quixote, is one of Near Earth Asteroids (NEAs which is the most probable candidate for the cometary origin, or otherwise as Jupiter-Family-Comets (JFCs. The aim of this study is to investigate the possibility of 3552 Don Quixote to be ejected from the Solar System. This paper presents an orbital evolution of 100 hypothetical asteroids generated by cloning 3552 Don Quixote. Investigation of its orbital evolution is conducted by using the SWIFT subroutine package, where the gravitational perturbations of eight major planets in the Solar System are considered. Over very short time scales (220 kyr relative to the Solar System life time (10 Gyr, the asteroid 3552 Don Quixote gave an example of chaotic motion that can cause asteroid to move outward and may be followed by escaping from the Solar System. Probability of ejection within the 220 kyr time scale is 50%. 9. Don Quixote Pond: A Small Scale Model of Weathering and Salt Accumulation Science.gov (United States) Englert, P.; Bishop, J. L.; Patel, S. N.; Gibson, E. K.; Koeberl, C. 2015-01-01 The formation of Don Quixote Pond in the North Fork of Wright Valley, Antarctica, is a model for unique terrestrial calcium, chlorine, and sulfate weathering, accumulation, and distribution processes. The formation of Don Quixote Pond by simple shallow and deep groundwater contrasts more complex models for Don Juan Pond in the South Fork of Wright Valley. Our study intends to understand the formation of Don Quixote Pond as unique terrestrial processes and as a model for Ca, C1, and S weathering and distribution on Mars. 10. Views of Oedipus in the Play Tebas Land: From Sophocles to Sergio Blanco Directory of Open Access Journals (Sweden) José Luis García Barrientos 2015-04-01 Full Text Available The relationship between myth and gaze is particularly paradoxical in the theatre, and has been so since the time of Ancient Greek theatre to the present. After all, it pertains, on the one hand, to the most substantial trait of this mode of imitation (Aristotle, which is directly linked to the stage, whereas the second means, narrative, is always mediated by a voice (the narrator or a gaze (the eye of the camera; and yet on the other hand the theatre is, even etymologically, a theatre par excellence: the fictive world is placed before the eyes of the spectator in a direct and effective manner. Since the gaze is of paramount importance to the very heart of the myth of Oedipus (from that of his parents, Laius and Jocasta, to the first-born, to the enemy-assassin, and finally to the saviour-king-spouse, and up to the unbearable one of anagnorisis, from which the only solution is blindness, in Greek tragedy, and its summit of Oedipus Rex, the impossible gaze finds substitutes in that of the choir and that of the playwright. On these bases, this paper examines the views of Oedipus which are intertwined in one of its most recent scenic avatars, namely, in Sergio Blanco's Tebas Land (2013, where the protagonist, called à la Kafka “S”, encompasses at the same time the functions of the playwright and of the chorus in a perverse meta-theatrical play, while also embodying the various historical interpretations and views of the myth that exist between Sophocles and Blanco, especially that of Sigmund Freud, the third vertex of the hermeneutical triangle, or the third eye of “S”. 11. Strategic planning 2007-2011, an opportunity for quality, competitiveness and excellence of the Laguna Verde Central; Planeacion estrategica 2007-2011, una oportunidad para la calidad, competitividad y excelencia de la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Rivera C, A. [CFE, Central Laguna Verde, Kilometro 42.5 Cardel Nautla, Veracruz (Mexico)]. e-mail: [email protected] 2007-07-01 The reason is to give to know to the nuclear community in Mexico the good results that it located in the 2006 to the Laguna Verde Nucleo electric Central in the classification of the World Association of Nuclear Operators (WANO) like one of the best in the worldwide scale, and their Strategic Plan 2007-2011 like an opportunity to continue improving the Quality, the Competitiveness and the Excellency in their Generating Units. It stands out that the fuel reloads are carried out in systemic form in less than 30 days, and also other achievements like it is the certificate granted by PROFEPA of Clean Industry, the renovation of the Certifications of the ISO-9001 and the ISO-14001, as well as the accredit of the Laboratories, and they will give data of the project of the increment of power that their power rose in 15%. For those results in the Strategic Planning 2007-2011 are pointed out that the Laguna Verde Central is a highly viable option in Mexico, when continuing with reloads that will allow a capacity factor up of 90%, and the other concepts that will give the obtaining of the qualification level 1 of WANO in this strategic period. Finally I will conclude with the good news for the Nuclear Industry in Mexico that published the Reforma newspaper at November 01, 2006: 'To the president of Mexico, Felipe Calderon, interests him to impel during his command the alternating energy sources to the hydrocarbons, known it is that the hydrocarbons (petroleum, coal or natural gas) they are finite, while the appetite of the world for the energy is infinite. As you they know, Mexico possesses a nuclear plant that generates energy starting from enriched uranium: the famous Laguna Verde Thermonuclear Central. He declared that Mexico can and it should advance for the one on the way to the energy generation for the nuclear road.' (Author)0. 12. Variación temporal y espacial de aves playeras en la laguna Barra de Navidad, Jalisco, en tres temporadas no reproductivas Directory of Open Access Journals (Sweden) Salvador Hernández 2012-09-01 Full Text Available Hay un escaso conocimiento de las aves playeras en los humedales costeros de Jalisco, y en particular en la laguna Barra de Navidad. El presente trabajo contribuye al conocimiento de este grupo de aves y describe su distribución temporal y espacial en la laguna Barra de Navidad durante tres temporadas no reproductivas (1999-2000, 2006-2007 y 2008-2009. Se realizaron censos mensuales de noviembre-abril en las tres temporadas con el fin de registrar todas las especies de aves playeras. Se identificaron 19 especies (tres residentes y 16 visitantes de invierno, de las cuales Charadrius wilsonia, Limosa fedoa y Tringa semipalmata presentaron la mayor abundancia. Doce especies son consideradas como prioritarias en la “Estrategia para la Conservación y Manejo de las Aves Playeras y su Hábitat en México”. El mayor número de especies fue registrado en noviembre, diciembre y marzo en la primera y tercera temporada. El mayor número de individuos fue registrado alimentándose en marea baja, principalmente en diciembre, enero y febrero de la primera y tercera temporada. En marea baja hubo un mayor número de especies e individuos alimentándose en la zona C. Esta zona se caracterizó por tener sustratos lodosos expuestos durante marea baja y que fueron aprovechados por las aves para alimentarse. La laguna Barra de Navidad proporcionó hábitats de alimentación y descanso para las aves residentes y migratorias. Sin embargo, estos hábitats se ven amenazados por las actividades humanas realizadas dentro de la laguna, que sin duda tendrán consecuencias negativas para la distribución y abundancia de las aves playeras. 13. Limnology in El Dorado: some surprising aspects of the regulation of phytoplankton productive capacity in a high-altitude Andean lake (Laguna de Guatavita, Colombia). Science.gov (United States) Donato, Jhon; Jimenez, Paola; Reynolds, Colin 2012-09-01 High-altitude mountain lakes remain understudied, mostly because of their relative inaccessibility. Laguna de Guatavita, a small, equatorial, high-altitude crater lake in the Eastern Range of the Colombian Andes, was once of high cultural importance to pre-Columban inhabitants, the original location of the legendary El Dorado. We investigated the factors regulating the primary production in Laguna de Guatavita (4degrees58'50" N - 73degrees46'43" W, alt. 2 935m.a.s.l., area: 0.11km2, maximum depth: 30m), during a series of three intensive field campaigns, which were conducted over a year-long period in 2003-2004. In each, standard profiles of temperature, oxygen concentration and light intensity were determined on each of 16-18 consecutive days. Samples were collected and analysed for chlorophyll and for biologically-significant solutes in GF/F-filtered water (NH4+, NO3(-), NO2(-); soluble reactive phosphorus). Primary production was also determined, by oxygen generation, on each day of the campaign. Our results showed that the productive potential of the lake was typically modest (campaign averages of 45-90mg C/m2.h) but that many of the regulating factors were not those anticipated intuitively. The lake is demonstrably meromictic, reminiscent ofkarstic dolines in higher latitudes, its stratification being maintained by solute- concentration gradients. Light penetration is poor, attributable to the turbidity owing to fine calcite and other particulates in suspension. Net primary production in the mixolimnion of Laguna de Guavita is sensitive to day-to-day variations in solar irradiance at the surface. However, deficiencies in nutrient availability, especially nitrogen, also constrain the capacity of the lake to support a phytoplankton. We deduced that Laguna de Guatavita is something of a limnological enigma, atypical of the common anticipation of a "mountain lake". While doubtlessly not unique, comparable descriptions of similar sites elsewhere are sufficiently 14. Bioaccumulation of some heavy metals in adult tilapia oreochromis niloticus in Southern part of Laguna de Bay International Nuclear Information System (INIS) Sandoval, Kristine L.; Padua, Haizelle O.; De Jesus, Editha E.; Enal, Maria Luisa A. 2010-01-01 Tilapia, Oreochromis niloticus, one of the most important fish species in Philippine aquaculture, is grown abundantly in Laguna de Bay. A preliminary study was conducted to determine the levels of accumulated mercury (Hg), cadmium (Cd) and lead (Pb) in the muscle tissue of this fresh water fish collected from February (wet season) to March (dry season) 2008 in the southern part of Laguna de Bay. Heavy metal analyses using atomic absorption spectrophotometer (AAS) showed a higher concentration of Hg and Cd during the wet season than in the dry season. However, analysis of variance revealed significant seasonal variation on only in Cd (P=0.0253). Lead, on the other hand, was not detected in the fish samples. The mean concentration set by FAO but the mean level of Cd (0.161 ppm) was almost equal to the limit given for fish. This could represent a significant health risk to the consuming public. (author) 15. Epidemiología de la enfermedad de Chagas en el municipio Andrés Eloy Blanco, Lara, Venezuela: infestación triatomínica y seroprevalencia en humanos Epidemiology of Chagas disease in Andrés Eloy Blanco, Lara, Venezuela: triatomine infestation and human seroprevalence Directory of Open Access Journals (Sweden) Claudina Rodríguez-Bonfante 2007-05-01 Full Text Available Se realizó un despistaje serológico y recolección de vectores en cuatro comunidades rurales del municipio Andrés Eloy Blanco, Estado Lara, Venezuela. La muestra fue escogida en forma sistemática y aleatoria basada en conglomerados familiares. Se muestrearon 869 habitantes para determinar anticuerpos anti-Trypanosoma cruzi y anti-Leishmania sp. por inmunofluorescencia indirecta, aceptando como positivo diluciones > a 1:32 para anticuerpos anti-T. cruzi no reactivos para antígenos de Leishmania sp., obteniendo una frecuencia de anticuerpos en la muestra de 6,9% (n = 60; de los cuales 46,66% son femeninos, 53,33% masculinos y 60% mayores de 40 años. Se observó que 5 (8,33% de los seropositivos eran menores de 10 años y 10 (16,66% menores de 20 años. Rhodnius prolixus y Panstrongylus geniculatus fueron los triatominos capturados, con índice de infestación de 1,9 y 10,54%, índice de colonización, del 0 y 18,18% en las viviendas infestadas e índice de infección a T. cruzi del 20 y 5,07%, respectivamente. Los resultados sugieren que existe una transmisión activa de la enfermedad de Chagas en el Municipio Andrés Eloy Blanco en las últimas dos décadas y que P. geniculatus está substituyendo a R. prolixus como vector de la enfermedad de Chagas.A seroepidemiological survey and vector captures were performed in four rural communities in Andrés Eloy Blanco, Lara State, Venezuela. Systematic random sampling was based on family clusters, with samples drawn from 869 individuals to determine anti-Trypanosoma cruzi and anti-Leishmania sp. antibodies by indirect immunofluorescence. Positive individuals were defined as > 1:32 for anti-T. cruzi antibody and non-reactive to Leishmania sp. antigen, revealing an antibody frequency of 6.9% (n = 60, of whom 46.66% were females and 53.33% males and 60% were over 39 years of age. Some 5 (8.33% seropositive individuals were under 10 years of age and 10 (16.66% under 20 years. Rhodnius prolixus and 16. Environmental geology of Laguna de las Perdices, Monte, Buenos Aires, Argentina OpenAIRE Dangavs, Nauris Vitauts 2009-01-01 El estudio de la laguna de las Perdices abarca tres aspectos: el geolimnológico, el geoambiental y el de remediación. El primero ha consistido en caracterizar el medio físico de un ambiente léntico típico de la Pampasia meridional prácticamente desconocido. El segundo, la evaluación del grado de deterioro natural y la contaminación físico-química y bacteriológica. El tercero propicia las medidas para su recuperación, máxime teniendo en cuenta que el Municipio de Monte pretende transformarla e... 17. New aspects in the radiological emergency plan outside the Nuclear power plant of Laguna Verde International Nuclear Information System (INIS) Alva L, S. 1991-01-01 The Mexican government through the National Commission of Nuclear Safety and Safeguards has imposed to the Federal Commission of Electricity to fulfill the requirement of having a functional Emergency Plan and under the limits that the regulator organisms in the world have proposed. The PERE (Plan of External Radiological Emergency) it has been created for the Nuclear Power station of Laguna Verde, Mexico 18. Blood Pressure Medicines Donât Work If People Donât Take Them PSA (:60) Centers for Disease Control (CDC) Podcasts 2016-09-13 This 60 second public service announcement is based on the September 2016 CDC Vital Signs report. Blood pressure medicines donât work if people donât take them. Learn how health care systems can work with patients to make taking medicines easier. Created: 9/13/2016 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP). Date Released: 9/13/2016. 19. The Authors of the Ingenious Hidalgo Don Quixote of La Mancha Directory of Open Access Journals (Sweden) Branka Kalenić Ramšak 2008-12-01 Full Text Available Even today literary criticism still considers the novel Don Quixote the first modern European novel because it fundamentally changes both the concept of literary creation and the findings regarding literary reception. Miguel de Cervantes Saavedra published the first part of his chivalric novel in 1605 in Madrid with the title El ingenioso hidalgo don Quijote de la Mancha. He published the second part, titled El ingenioso caballero don Quijote de la Mancha, ten years later (i.e., in 1615, again in Madrid. Why did Cervantes change the title in the second part of his novel and thus transform Don Quixote the hidalgo ‘nobleman’ into Don Quixote the caballero ‘knight, nobleman, horseman’? In Spanish literature of Cervantes’ time, writers often borrowed texts from one another, wrote sequels to them, and reworked them into humorous poems, jocular one-act plays, or unusual parodies. The Baroque concept of imitation was not understood as plagiarism, but rather as a positive approach to creativity. One of Cervantes’ most enthusiastic imitators was Alonso Fernández de Avellaneda. He hated Cervantes, but loved Don Quixote so much that he wrote a sequel to it in the form of a chivalric novel. In 1614, Avellaneda published his novel titled Segundo tomo del ingenioso hidalgo don Quijote de la Mancha (The Second Part of the Ingenious Hidalgo of La Mancha in Tarragona. Who is hidden behind the name Alonso Fernández de Avellaneda? To date, literary history has not been able to establish with certainty who the author of this “second part” was; this work represents the greatest literary mystery of all time in Spanish literature. In the 1960s a theory developed among Cervantes experts that for now seems to be the most convincing in determining Avellaneda’s true identity. In his article “ El Quijote y los libros” (Don Quixote and Books of 1969, Martín de Riquer presented the first well-founded hypothesis claiming that the writer Alonso Fern 20. Distribución de los microcrustáceos en lagunas de Castilla-La Mancha. Ciclos estacionales y migración vertical en lagunas cársticas estratificadas OpenAIRE Boronat Chirivella, Mª Dolores 2003-01-01 RESUMEN Este trabajo presenta el estudio ecológico de los microcrustáceos planctónicos o semiplanctónicos de las aguas continentales siendo tres los objetivos principales. (1). Relacionar la distribución de estos organismos con las características físico-químicas de sus hábitats e intentar establecer una tipología de los mismos basada en las asociaciones de microcrustáceos. Se estudiaron los litorales de 45 lagunas de Castilla-La Mancha, encontrándose un total de 82 especies (32 copépod... 1. Environmental evidence of fossil fuel pollution in Laguna Chica de San Pedro lake sediments (Central Chile) International Nuclear Information System (INIS) Chirinos, L.; Rose, N.L.; Urrutia, R.; Munoz, P.; Torrejon, F.; Torres, L.; Cruces, F.; Araneda, A.; Zaror, C. 2006-01-01 This paper describes lake sediment spheroidal carbonaceous particle (SCP) profiles from Laguna Chica San Pedro, located in the Biobio Region, Chile (36 o 51' S, 73 o 05' W). The earliest presence of SCPs was found at 16 cm depth, corresponding to the 1915-1937 period, at the very onset of industrial activities in the study area. No SCPs were found at lower depths. SCP concentrations in Laguna Chica San Pedro lake sediments were directly related to local industrial activities. Moreover, no SCPs were found in Galletue lake (38 o 41' S, 71 o 17.5' W), a pristine high mountain water body used here as a reference site, suggesting that contribution from long distance atmospheric transport could be neglected, unlike published data from remote Northern Hemisphere lakes. These results are the first SCP sediment profiles from Chile, showing a direct relationship with fossil fuel consumption in the region. Cores were dated using the 21 Pb technique. - The lake sediment record of SCPs shows the record of fossil-fuel derived pollution in Central Chile 2. Environmental evidence of fossil fuel pollution in Laguna Chica de San Pedro lake sediments (Central Chile) Energy Technology Data Exchange (ETDEWEB) Chirinos, L. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile)]. E-mail: [email protected]; Rose, N.L. [Environmental Change Research Centre, University College London, 26 Bedford Way, London WG1HOAP (United Kingdom); Urrutia, R. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile); Munoz, P. [Departamento de Biologia Marina, Universidad Catolica del Norte, Larrondo 1281, Coquimbo (Chile); Torrejon, F. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile); Torres, L. [Departamento de Botanica, Universidad de Concepcion, Concepcion (Chile); Cruces, F. [Departamento de Botanica, Universidad de Concepcion, Concepcion (Chile); Araneda, A. [Centro de Ciencias Ambientales EULA-Chile, Universidad de Concepcion, PO Box 160-C, Concepcion (Chile); Zaror, C. [Facultad de Ingenieria Quimica, Universidad de Concepcion, Concepcion (Chile) 2006-05-15 This paper describes lake sediment spheroidal carbonaceous particle (SCP) profiles from Laguna Chica San Pedro, located in the Biobio Region, Chile (36{sup o} 51' S, 73{sup o} 05' W). The earliest presence of SCPs was found at 16 cm depth, corresponding to the 1915-1937 period, at the very onset of industrial activities in the study area. No SCPs were found at lower depths. SCP concentrations in Laguna Chica San Pedro lake sediments were directly related to local industrial activities. Moreover, no SCPs were found in Galletue lake (38{sup o} 41' S, 71{sup o} 17.5' W), a pristine high mountain water body used here as a reference site, suggesting that contribution from long distance atmospheric transport could be neglected, unlike published data from remote Northern Hemisphere lakes. These results are the first SCP sediment profiles from Chile, showing a direct relationship with fossil fuel consumption in the region. Cores were dated using the {sup 21}Pb technique. - The lake sediment record of SCPs shows the record of fossil-fuel derived pollution in Central Chile. 3. Developing and modeling of the 'Laguna Verde' BWR CRDA benchmark International Nuclear Information System (INIS) Solis-Rodarte, J.; Fu, H.; Ivanov, K.N.; Matsui, Y.; Hotta, A. 2002-01-01 Reactivity initiated accidents (RIA) and design basis transients are one of the most important aspects related to nuclear power reactor safety. These events are re-evaluated whenever core alterations (modifications) are made as part of the nuclear safety analysis performed to a new design. These modifications usually include, but are not limited to, power upgrades, longer cycles, new fuel assembly and control rod designs, etc. The results obtained are compared with pre-established bounding analysis values to see if the new core design fulfills the requirements of safety constraints imposed on the design. The control rod drop accident (CRDA) is the design basis transient for the reactivity events of BWR technology. The CRDA is a very localized event depending on the control rod insertion position and the fuel assemblies surrounding the control rod falling from the core. A numerical benchmark was developed based on the CRDA RIA design basis accident to further asses the performance of coupled 3D neutron kinetics/thermal-hydraulics codes. The CRDA in a BWR is a mostly neutronic driven event. This benchmark is based on a real operating nuclear power plant - unit 1 of the Laguna Verde (LV1) nuclear power plant (NPP). The definition of the benchmark is presented briefly together with the benchmark specifications. Some of the cross-sections were modified in order to make the maximum control rod worth greater than one dollar. The transient is initiated at steady-state by dropping the control rod with maximum worth at full speed. The 'Laguna Verde' (LV1) BWR CRDA transient benchmark is calculated using two coupled codes: TRAC-BF1/NEM and TRAC-BF1/ENTREE. Neutron kinetics and thermal hydraulics models were developed for both codes. Comparison of the obtained results is presented along with some discussion of the sensitivity of results to some modeling assumptions 4. Efecto de tres tipos de presas vivas en la larvicultura de bagre blanco (Sorubim cuspicaudus Directory of Open Access Journals (Sweden) Martha Prieto-Guevara 2013-11-01 Full Text Available Objetivo. Evaluar el efecto de diferentes presas vivas en la larvicultura de bagre blanco (Sorubim cuspicaudus. Materiales y métodos. Al inicio de la alimentación exógena de Sorubim cuspicaudus, se ofreció zooplancton producido en mesocosmos (T1, zooplancton silvestre (T2 y nauplios de Artemia (T3, en concentración de 10.000 zoop/L, dos veces al día, durante seis días. Se utilizaron 18 acuarios de cinco litros de volumen útil, con densidad de 25 Larvas/L, seis réplicas por tratamiento en un diseño al azar. Se estimaron la ganancia en peso (Gp y longitud (Gl, tasa de crecimiento específico (G, sobrevivencia (S, resistencia al estrés (Re, mortalidad acumulada (Ma y mortalidad por canibalismo (Mc. Resultados. Las larvas alimentadas con mesocosmos presentaron la mayor sobrevivencia (81.3±15.9%; aunque el mejor crecimiento lo presentaron las larvas alimentadas con zooplancton silvestre (T2 las cuales presentaron la mayor mortalidad (42.0±10.7% y la menor resistencia al estrés (30.0±33.0%. El canibalismo se observó en todos los tratamientos, oscilando entre 4.0 (T2 y 14.3% (T1 sin diferencias significativas entre estos valores (p>0.05. Conclusiones. El uso de zooplancton producido bajo condiciones controladas permitió una alta sobrevivencia, adecuado desempeño y resistencia de las larvas, perfilándose como alternativa viable en la primera alimentación de bagre blanco. 5. A radiation monitoring system model for the Laguna Verde nuclear power training simulator International Nuclear Information System (INIS) Ocampo, M.H.; DeAlbornoz, B.A. 1988-01-01 A model for the Radiation Monitoring System of the Laguna Verde Boiling Water Reactor training simulator is presented. This model comprises enough definitions to assure interactions with the processes related, directly or indirectly, with the transport of radioisotopes. It is capable of following a dynamic behavior of the plant so an operator could be trained to become aware of nuclear radiation hazards. The model is composed of three parts: the electronics for the Process and Area Radiation Monitoring System; a lumped parameter transport model for the most representative radioisotopes; and the interactions with the modeled processes as well as with process not being simulated. The first part represents the radiation monitor controls in the vertical board panels of the nuclear station. The second part allows the carrying of nuclear isotopes between processes. The third part defines the way that the process interacts with the electronics at the point of release to environment or the point of detection. Each part of the model has been tested individually, and the transport model has been incorporated as a part of each process required to simulate nuclear radiation. The model parameters has been calculated using typical BWR nuclear radiation data, and Laguna Verde heat balance data at 100% design power. However, tunning will be necessary once the Simulator is integrated and tested. The tunning allows each detecting channel to behave as expected 6. TRATAMIENTO DE LODOS DE FONDO DE LAGUNAS FACULTATIVAS CON ESTABILIZACIÓN EN CONDICIONES DE LABORATORIO Directory of Open Access Journals (Sweden) Jhon Jairo Feria Diaz Full Text Available En este artículo se muestran los resultados obtenidos en el proceso de estabilización química de lodos de lagunas de estabilización, mediante la adición de cal hidratada común. Se adicionaron en condiciones controladas de laboratorio, dosis de cal al 5 %, 7 %, 9 %, 10 %, 11 %, 12 % y 15 % a una muestra de lodos de fondo de la laguna primaria del sistema de tratamiento de aguas residuales de la ciudad de Montería, Colombia. Se analizaron la peligrosidad del lodo (corrosividad, inflamabilidad y reactividad y las concentraciones de sulfuros, metales pesados (As, Ba, Cd, Cr, Hg, Ag, Pb, Se, coliformes, salmonella, bacterias mesófilas, áscaris y otros helmintos, antes y después de aplicar una dosis optima al 10%. Con esta dosis se logró controlar la reactividad por sulfuros y cianuros, pero no se redujeron las concentraciones de coliformes y de bacterias mesófilas. Algunos metales pesados (Cd, Cr, Hg, Ag, Pb aumentaron luego de la aplicación de la dosis de cal hidratada, aunque las concentraciones halladas no constituyen peligro ambiental, de acuerdo a la normatividad ambiental vigente. 7. Modernization of electric power systems of the Laguna Verde Nuclear Power Plant; Modernizacion de los sistemas electricos de potencia de la Central Nuclear de Laguna Verde Energy Technology Data Exchange (ETDEWEB) Gabaldon, M. A.; Gonzalez, J. J.; Prieto, I. 2011-07-01 The Power Increase Project of Laguna Verde Nuclear Plant has entailed the replacement, in one unique outage, of the main power electrical systems of the Plant (Isolated Phase Bars, Generator Circuit Breaker and Main Transformer) as well as the replacement of the Turbo-group. The simultaneous substitution of these entire system has never been done by any other Plant in the world, representing an engineering challenge that embraced the design of the new equipment up to the planning, coordination and management of the construction and commissioning works, which were successfully carried out by Iberdrola within the established outage period /47 days) for both units. (Author) 8. Chemistry of Hot Spring Pool Waters in Calamba and Los Banos and Potential Effect on the Water Quality of Laguna De Bay Science.gov (United States) Balangue, M. I. R. D.; Pena, M. A. Z.; Siringan, F. P.; Jago-on, K. A. B.; Lloren, R. B.; Taniguchi, M. 2014-12-01 Since the Spanish Period (1600s), natural hot spring waters have been harnessed for balneological purposes in the municipalities of Calamba and Los Banos, Laguna, south of Metro Manila. There are at more than a hundred hot spring resorts in Brgy. Pansol, Calamba and Tadlac, Los Banos. These two areas are found at the northern flanks of Mt. Makiling facing Laguna de Bay. This study aims to provide some insights on the physical and chemical characteristics of hot spring resorts and the possible impact on the lake water quality resulting from the disposal of used water. Initial ocular survey of the resorts showed that temperature of the pool water ranges from ambient (>300C) to as high as 500C with an average pool size of 80m3. Water samples were collected from a natural hot spring and pumped well in Los Banos and another pumped well in Pansol to determine the chemistry. The field pH ranges from 6.65 to 6.87 (Pansol springs). Cation analysis revealed that the thermal waters belonged to the Na-K-Cl-HCO3 type with some trace amount of heavy metals. Methods for waste water disposal are either by direct discharge down the drain of the pool or by discharge in the public road canal. Both methods will dump the waste water directly into Laguna de Bay. Taking in consideration the large volume of waste water used especially during the peak season, the effect on the lake water quality would be significant. It is therefore imperative for the environmental authorities in Laguna to regulate and monitor the chemistry of discharges from the pool to protect both the lake water as well as groundwater quality. 9. Viajando con Don Quijote en el siglo XXI Directory of Open Access Journals (Sweden) Odilíe Rojas-López 2006-06-01 Full Text Available Don Quixote has ridden with us for a long time now, and as if his fight against windmills were not enough, Don Quixote still has many more difficult situations to combat in the present times. Will the Knight of the Sad Figure accomplish this new deed? It is our challenge to find an answer to this inquiry. For this purpose, the author of this essay inserts the Knight of the Sad Figure in XXI century society. The author transforms the values, costumes and points of view of the times of the literary piece and establishes a series of relationships between the literary text, the main character and several current daily life situations. Don Quixote will certainly continue his fight against all the conditions we encounter nowadays. There is no doubt, then, that this knight still lives among us. 10. Laguna Verde simulator: A new TRAC-RT based application International Nuclear Information System (INIS) Munoz Cases, J.J.; Tanarro Onrubia, A. 2006-01-01 In a partnership with GSE Systems, TECNATOM is developing a full scope training simulator for Laguna Verde Unit 2 (LV2). The simulator design is based upon the current 'state-of-the art technology' regarding the simulation platform, instructor station, visualization tools, advanced thermalhydraulics and neutronics models, I/O systems and automated model building technology. When completed, LV2 simulator will achieve a remarkable level of modeling fidelity by using TECNATOM's TRAC-RT advanced thermalhydraulic code for the reactor coolant and main steam systems, and NEMO neutronic model for the reactor core calculations. These models have been utilized up to date for the development or upgrading of nine NPP simulators in Spain and abroad, with more than 8000 hours of training sessions, and have developed an excellent reputation for its robustness and high fidelity. (author) 11. May 2013 Groundwater and Surface Water Sampling at the Rio Blanco, Colorado, Site (Data Validation Package) Energy Technology Data Exchange (ETDEWEB) Hutton, Rick [S.M. Stoller Corporation, Broomfield, CO (United States) 2013-10-01 Annual sampling was conducted at the Rio Blanco, Colorado, site for the Long-Term Hydrologic Monitoring Program May 14-16, 2013, to monitor groundwater and surface water for potential radionuclide contamination. Sampling and analyses were conducted as specified in Sampling and Analysis Plan for the U.S. Department of Energy Office of Legacy Management Sites (LMS/PRO/S04351, continually updated). A duplicate sample was collected from location CER #1 Black Sulphur. Samples were analyzed for gamma-emitting radionuclides by high-resolution gamma spectrometry and for tritium using the conventional and enrichment methods. 12. Don Quijote in Nineteenth-Century English Theatre Directory of Open Access Journals (Sweden) J. A. Garrido Ardila 2014-12-01 Full Text Available This article brings to light a group of Cervantine English literary works hitherto unknown to present-day Cervantes studies: seven theatrical adaptations of Don Quixote (two anonymous ones in addition to those by Charles Dibdin, Joseph Moser, G. A. Macfarren, C. A. Maltby and P. Milton, a comedy with a Quixotic title (by George Dance, and five Quixotic fictions (two anonymous, in addition to those by Lily Spender, Maurice Hewlett and A. T. Quiller-Couch. Three of these plays, had been noted by Leopoldo Rius in 1899 (Moser, Macfarren, Maltby; the other four are presented for the first time here. In order to chart a fuller and more complete history of Don Quixote on the English stage, this article provides relevant information on those seven plays. An examination of these works reinforces the previous theses that underscore the essentially comical nature of Quixotic plays in nineteenth-century England, a fact of relevance in the study of the English reception of Don Quixote in the course of that century. 13. Distributed Observer Network (DON), Version 3.0, User's Guide Science.gov (United States) Mazzone, Rebecca A.; Conroy, Michael P. 2015-01-01 The Distributed Observer Network (DON) is a data presentation tool developed by the National Aeronautics and Space Administration (NASA) to distribute and publish simulation results. Leveraging the display capabilities inherent in modern gaming technology, DON places users in a fully navigable 3-D environment containing graphical models and allows the users to observe how those models evolve and interact over time in a given scenario. Each scenario is driven with data that has been generated by authoritative NASA simulation tools and exported in accordance with a published data interface specification. This decoupling of the data from the source tool enables DON to faithfully display a simulator's results and ensure that every simulation stakeholder will view the exact same information every time. 14. Palinology and stratigraphic sequences of the well ELS-1, Laguna Salada, B.C., Mexico; Palinologia y secuencias estratigraficas del pozo ELS-1, Laguna Salada, B.C., Mexico Energy Technology Data Exchange (ETDEWEB) Helenes Escamilla, Javier [CICESE, Ensenada, B.C. (Mexico) 1999-04-01 Palinological analysis of 16 samples from the well ELS-1 in Laguna Salada, allows recognition of environmental changes in the drilled section. No age assignments are made because of the low diversity of the palinological assemblages recovered. These assemblages include species with ages from Campanian to Pleistocene. The cretaceous forms indicate reworking from a cretaceous unit within the Colorado river drainage basin. Integration of the palinological, lithological and well log data permit the recognition of three main cycles. The lower one is regressive and contains mostly fluvial to deltaic shallow marine sediments. The intermediate cycle is transgressive-regressive, contains the maximum flooding surface of the section studied and represents an interval of strong tectonic movements with well developed marine transgressions. The upper cycle is also transgressive-regressive, with lagoon and distal alluvial fan deposits. [Spanish] El analisis palinologico de 16 muestras del pozo: ELS-1 del proyecto geotermico de Laguna Salada permite reconocer cambios ambientales en la seccion perforada. La baja diversidad de los conjuntos palinologicos recuperados impide determinar edades. Se observan especies indicadoras de edades desde Campaniese hasta Pleistoceno. Las formas cretacicas indican retrabajo de alguna unidad cretacica dentro de la cuenca del rio Colorado. La integracion de datos palinologicos, litologicos y de registros geofisicos, permite reconocer tres ciclos principales. El ciclo inferior es regresivo y contiene principalmente sedimentos fluviales a deltaicos de niveles bajos del mar. El ciclo intermedio, es transgresivo-regresivo, contiene la superficie de inundacion maxima de toda la seccion estudiada y representa una etapa de movimientos tectonicos fuertes con transgresiones marinas bien desarrolladas. El ciclo superior tambien es transgresivo-regresivo, con depositos lagunares y de abanicos aluviales distales. 15. Introduction of fuel GE14 in the nuclear power plant of Laguna Verde for the extended increase of power International Nuclear Information System (INIS) Hernandez M, N.; Vargas A, A. F.; Cardenas J, J. B.; Contreras C, P. 2008-01-01 The project of extended increase of power responds to a necessity of electrical energy in the country, increasing the thermal exit of the reactors of the nuclear power plant of Laguna Verde of 2027 MWt to 2317 MWt. In order to support this transition, changes will make in the configuration of the reactor core and in the operation strategies of the cycle, also they will take initiatives to optimize the economy in fuel cycle. At present in both reactors of the nuclear plant of Laguna Verde fuel GE12 is used. The fuel GE14 presents displays with respect to the GE12, some improvements in the mechanical design and consequently in its performance generally. Between these improvements we can mention: 1. Spacers of high performance. 2. Shielding with barrier. 3. Filter for sweepings d ebris a nd 4. Fuel rods of minor partial length. The management of nuclear power plants has decided to introduce the use of fuel GE14 in Laguna Verde in the reload 14 for Unit 1 and of the reload 10 for Unit 2. The process of new introduction fuel GE14 consists of two stages, first consists on subjecting the one new design of fuel to the regulator organism in the USA: Nuclear Regulatory Commission, in Mexico the design must be analyzed and authorized by the National Commission of Nuclear Safety and Safeguards, for its approval of generic form, by means of the demonstration of the fulfillment with the amendment 22 of GESTAR II, the second stage includes the specific analyses of plant to justify the use of the new fuel design in a reload core. The nuclear plant of Laguna Verde would use some of the results of the security analyses that have been realized for the project of extended increase of power with fuel GE14, to document the specific analyses of plant with the new fuel design. The result of the analyses indicates that the reload lots are increased of 116-120 assemblies in present conditions (2027 MWt) to 140-148 assemblies in conditions of extended increase of power (2317 MWt). (Author) 16. GC–MS analysis of bioactive compounds present in different extracts of an endemic plant Broussonetia luzonica (Blanco) (Moraceae) leaves OpenAIRE Franelyne Pataueg Casuga; Agnes Llamasares Castillo; Mary Jho-Anne Tolentino Corpuz 2016-01-01 Objective: To investigate and characterize the chemical composition of the different crude extracts from the leaves of Broussonetia luzonica (Blanco) (Moraceae) (B. luzonica), an endemic plant in the Philippines. Methods: The air dried leaves were powdered and subjected to selective sequential extraction using solvents of increasing polarity through percolation, namely, n-hexane, ethyl acetate and methanol to obtain three different extracts. Then, each of the extracts was further subjected... 17. Reading "Las Meninas": An Ekphrastic Approach to Teaching "Don Quijote" Science.gov (United States) Ortuno, Marian 2012-01-01 Reading and teaching "Don Quijote" present multiple challenges to twenty-first century students and instructors who are culturally and historically distanced from the seventeenth century. With "Las Meninas" serving as a visual lexicon for cuing correlative themes and events in "Don Quijote", the instructor, through an ekphrastic, interdisciplinary… 18. Modernization of the Electric Power Systems (transformers, rods and switches) in the Laguna Verde Nuclear Power Plant (Mexico) International Nuclear Information System (INIS) Gonzalez Solarzano, J. J.; Gabaldon Martin, M. A.; Pallisa Nunez, J.; Florez Ordeonez, A.; Fernandez Corbeira, A.; Prieto Diez, I. 2010-01-01 Description of the changes made in the Electric Power Systems as a part of the power increase project in the Laguna Verde Nuclear Power Plant (Mexico). The main electrical changes to make, besides the turbo group, are the main generation transformers, the isolated rods and the generation switch. 19. Genio y figura de don Alfonso Reyes Directory of Open Access Journals (Sweden) Eduardo Carranza 1968-04-01 Full Text Available Entre varias, escojo esta: por sobria y conmovida a un tiempo. La escribió Juan Fernández Figueroa para su revista " Indice", de Madrid. Nos parece ver a don Alfonso en el rellano de la escalera -al fondo, sus libros; más allá, toda su vida, noble y pura- nos parece verle por última vez, inclinado ya sobre la baranda de la muerte. Tiene la calidad y el dinamismo de unos cuantos dibujos rápidos, nerviosos, esta imagen última de don Alfonso Reyes. 20. Dostoyevski and Don Quijote: Poetics and Aesthetics of a Delusion Directory of Open Access Journals (Sweden) Tamara Djermanovic 2015-12-01 Full Text Available In Fedor Mikhailovich Dostoevsky’s body of work (1821-1881 one can find more than thirty references to Don Quixote; while some of them allude to the novel of Don Quixote itself, other ones refer to Cervantes’ hero as an archetypal figure. Since decades ago, the Russian literary criticism has been interested in the Russian quixotism – including Dostoevsky’s work – and important studies on this subject have been published recently. This study follows Dostoevsky’s references on La Mancha’s Knight as an independent figure of Cervantes’ novel, and the different symbolism Don Quixote’s figure has had in both Russian people and Russian intelligentsia. 1. Field reconnaissance of the effects of the earthquake of April 13, 1973, near Laguna de Arenal, Costa Rica Science.gov (United States) Plafker, George 1973-01-01 At about 3:34 a.m. on April 13, 1973, a moderate-sized, but widely-felt, earthquake caused extensive damage with loss of 23 lives in a rural area of about 150 km2 centered just south of Laguna de Arenal in northwestern Costa Rica (fig. 1). This report summarizes the results of the writer's reconnaissance investigation of the area that was affected by the earthquake of April 13, 1973. A 4-day field study of the meizoseismal area was carried out during the period from April 28 through May 1 under the auspices of the U.S. Geological Survey. The primary objective of this study was to evaluate geologic factors that contributed to the damage and loss of life. The earthquake was also of special interest because of the possibility that it was accompanied by surface faulting comparable to that which occurred at Managua, Nicaragua, during the disastrous earthquake of December 23, 1972 (Brown, Ward, and Plafker, 1973). Such earthquake-related surface faulting can provide scientifically valuable information on active tectonic processes at shallow depths within the Middle America arc. Also, identification of active faults in this area is of considerable practical importance because of the planned construction of a major hydroelectrical facility within the meizoseismal area by the Instituto Costarricense de Electricidad (I.C.E.). The project would involve creation of a storage reservoir within the Laguna de Arenal basin and part of the Río Arenal valley with a 75 m-high earthfill dam across Río Arenal at a point about 10 km east of the outlet of Laguna de Arenal. 2. Fungal flora and deoxynivalenol (DON) level in wheat from Jeddah ... African Journals Online (AJOL) This study aimed to explore the fungal flora along with the DON concentration in the collected wheat samples from Jeddah market to correlate between this flora and the detected DON. Whole grain wheat samples were collected from Jeddah market and this represents imported and locally produced wheat. The results ... 3. Carbonate Formation And Diagenesis In Pastos Grandes Laguna (Bolivia): Modern Analog For The South Atlantic Cretaceous Presalt Travertinoid Deposits Science.gov (United States) Muller, E.; Ader, M.; Gérard, E.; Virgone, A.; Gaucher, E.; Bougeault, C.; Durlet, C.; Moreira, M. A.; Virgile, R.; Vennin, E.; Agogué, H.; Hugoni, M. 2017-12-01 The Cretaceous Presalt travertinoid deposits of the South Atlantic are usually considered as "strange deposits" having poor equivalents in modern environments. Pastos Grandes Laguna, which is located in a 2.9 Ma caldera on the andean-bolivian Altiplano (at 4450 m), is intersected by active faults with hydrothermal fluids and presents a spherulitic plateform with similar sedimentological facies to the Presalt: halite and bedded evaporites, shrub-shaped calcites, ooids, pisolites and various stromatolites. Pastos Grandes Laguna is certainly one of the best modern analog of the Presalt for investigating the on going processes of carbonate deposition and diagenesis and the influence of biology. During two expeditions, we recovered samples of gas, water and microbial mats from the hydrothermal sources to the evaporating zones on the spherulitic plateform. These samples are being analyzed to determine 1) the influence of the gases emitted at the hydrothermal sources (chemical and isotopic composition) on the chemistry of the Laguna and the mineralogy of its sediments and 2) the role of ecosystems that develop in this environment on carbonate formation. Preliminary results on gas composition, corrected for the atmospheric contribution, indicates a magmatic source of CO2 partly mantellic associated with a small crustal contribution. Other initial results have so far indicated that CO2 gas emissions, evaporation, as well as photosynthesis and respiration play a role on water chemistry and carbonate precipitation. This study will contribute to the overall understanding of the role of organisms in sedimentation and the predictive diagenetic evolution of hydrothermal and lacustrine deposits. 4. Effect of test exercises and mask donning on measured respirator fit. Science.gov (United States) Crutchfield, C D; Fairbank, E O; Greenstein, S L 1999-12-01 Quantitative respirator fit test protocols are typically defined by a series of fit test exercises. A rationale for the protocols that have been developed is generally not available. There also is little information available that describes the effect or effectiveness of the fit test exercises currently specified in respiratory protection standards. This study was designed to assess the relative impact of fit test exercises and mask donning on respirator fit as measured by a controlled negative pressure and an ambient aerosol fit test system. Multiple donnings of two different sizes of identical respirator models by each of 14 test subjects showed that donning affects respirator fit to a greater degree than fit test exercises. Currently specified fit test protocols emphasize test exercises, and the determination of fit is based on a single mask donning. A rationale for a modified fit test protocol based on fewer, more targeted test exercises and multiple mask donnings is presented. The modified protocol identified inadequately fitting respirators as effectively as the currently specified Occupational Safety and Health Administration (OSHA) quantitative fit test protocol. The controlled negative pressure system measured significantly (p < 0.0001) more respirator leakage than the ambient aerosol fit test system. The bend over fit test exercise was found to be predictive of poor respirator fit by both fit test systems. For the better fitting respirators, only the talking exercise generated aerosol fit factors that were significantly lower (p < 0.0001) than corresponding donning fit factors. 5. CDC Vital SignsâBlood Pressure Medicines Donât Work If People Donât Take Them Centers for Disease Control (CDC) Podcasts 2016-09-13 Blood pressure medicines donât work if people donât take them. Learn how health care systems can work with patients to make taking medicines easier. Created: 9/13/2016 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP). Date Released: 9/13/2016. 6. Trouble Don't Last Science.gov (United States) Pearsall, Shelley 2004-01-01 Even as a child, Pearsall questioned social injustice and prejudice. In her own community in Ohio and, as she grew, all over the world, she saw social inequities she could neither understand nor accept. Her novel "Trouble Don't Last," takes place during the era of the Underground Railroad. The chapter included here pulls us in… 7. Don Quijote en Canadá Directory of Open Access Journals (Sweden) Cristina Botella González 2007-01-01 Full Text Available Conocer a Cervantes y su obra.- Descubrir otros países y artistas.- Conocer al personaje de Don Quijote.- Familiarizarse con los personajes principales.- Relacionar la pintura y la literatura.- Desarrollar habilidades manuales y artísticas.- Potenciar la creatividad. 8. Determinación de Glifosato mediante inmunoensayo enzimático (ELISA en el Paisaje Protegido Laguna de Rocha y su entorno, Uruguay. Directory of Open Access Journals (Sweden) Daniela Nardo 2015-12-01 Full Text Available En el entorno de la Laguna de Rocha se ha visto incrementada la superficie dedicada a las actividades agrícolas con un mayor uso de plaguicidas, entre ellos el herbicida glifosato, usado en cultivos de soja principalmente. Mediante la utilización de técnicas de inmunoensayo enzimático (ELISA, se investigó la presencia de glifosato en la Laguna y algunos de sus afluentes en dos momentos específicos de tiempo. Se detectó glifosato en 27 de las 28 muestras estudiadas. Muestras positivas por ELISA fueron confirmadas por cromatografía iónica. El método ELISA demostró ser una herramienta de screening adecuada para determinar la presencia de glifosato en agua. 9. Congener-specific polychlorinated biphenyl patterns in eggs of aquatic birds from the lower Laguna Madre, Texas Science.gov (United States) Mora, Miguel A. 1996-01-01 Eggs from four aquatic bird species nesting in the Lower Laguna Madre, Texas, were collected to determine differences and similarities in the accumulation of congener-specific polychlorinated biphenyls (PCBs) and to evaluate PCB impacts on reproduction. Because of the different toxicities of PCB congeners, it is important to know which congeners contribute most to total PCBs. The predominant PCB congeners were 153, 138, 180, 110, 118, 187, and 92. Collectively, congeners 153, 138, and 180 accounted for 26 to 42% of total PCBs. Congener 153 was the most abundant in Caspian terns (Sterna caspia) and great blue herons (Ardea herodias) and congener 138 was the most abundant in snowy egrets (Egretta thula) and tricolored herons (Egretta tricolor). Principal component analysis indicated a predominance of higher chlorinated biphenyls in Caspian terns and great blue herons and lower chlorinated biphenyls in tricolored herons. Snowy egrets had a predominance of pentachlorobiphenyls. These results suggest that there are differences in PCB congener patterns in closely related species and that these differences are more likely associated with the species' diet rather than metabolism. Total PCBs were significantly greater (p birds from the Lower Laguna Madre were below concentrations known to affect bird reproduction. 10. Technical assistance in relationship with the reloading analysis of the Laguna Verde Unit 2 reactor. Executive abstract International Nuclear Information System (INIS) Alonso V, G.; Castro B, M.; Gallegos E, R.; Hernandez L, H.; Montes T, J.L.; Ortiz S, J. J.; Perusquia C, R. 1993-11-01 The objective of the report was to carry out a comparative analysis of costs of energy generation among the designs GE9B of General Electric, 9X9-IX of SIEMENS and SVEA-96 of ABB ATOM, proposed to be used as recharge fuel in the Unit 2 of the Laguna Verde Nuclear Power station. (Author) 11. El rol de las ONG de España en el internacionalización de la causa de las Damas de Blanco. Estudio de caso: Solidaridad Española con Cuba (2005-2012) OpenAIRE Tenjo Montes, Jineth Milena 2014-01-01 El interés de este estudio de caso es demostrar el rol de la ONG Solidaridad Española con Cuba en la creación de una red transnacional de defensa de las Damas de Blanco, un movimiento social cubano disidente. Esto, tras reconocer que el apoyo por parte de ésta y otras organizaciones e instituciones internacionales es de gran importancia para lograr las reivindicaciones sociales propuestas por las Damas de Blanco, a partir de los hechos ocurridos en la Primavera Negra en el año 2003. Tanto las... 12. Validation of the thermal balance of Laguna Verde turbine under conditions of extended power increase International Nuclear Information System (INIS) Castaneda G, M. A.; Cruz B, H. J.; Mercado V, J. J.; Cardenas J, J. B.; Garcia de la C, F. M. 2012-10-01 The present work is a continuation of the task: Modeling of the vapor cycle of Laguna Verde with the PEPSE code to conditions of thermal power licensed at present (2027 MWt) in which the modeling of the vapor cycle of the nuclear power plant of Laguna Verde was realized with PEPSE code (Performance Evaluation of Power System Efficiencies). Once reached the conditions of nominal operation of extended power increase, operating both units to 2371 MWt; after the tests phase of starting-up and operation is necessary to carry out a verification of the proposed design of the vapor cycle for the new operation conditions. All this, having in consideration that the vapor cycle designer only knows the detail of the prospective performance of the main turbine, for all the other components (for example pumps, heat inter changers, valves, reactor, humidity separators and re-heaters, condensers, etc.) makes generic suppositions based on engineering judgment. This way carries out the calculations of thermal balance to determine the guaranteed gross power. The purpose of the present work is to comment the detail of the validation carried out of the specific thermal balance (thermal kit) of the nuclear power plant, making use of the design characteristics of the different components that conform the vapor cycle. (Author) 13. Evaluación de los recursos hídricos en cabecera de las subcuencas de las provincias de Andahuaylas y Chincheros: levantamiento topográfico de vaso de lagunas OpenAIRE Autoridad Nacional del Agua. Dirección de Conservación y Planeamiento de Recursos Hídricos; Autoridad Nacional del Agua. Administración Local de Agua Bajo Apurímac Pampas 2013-01-01 Describe las características principales del levantamiento topográfico de vasos de lagunas en el ámbito de las sub-cuencas de las provincias de Andahuaylas y Chincheros, con el fin de evaluar futuros proyectos de afianzamiento hídrico. Las lagunas descritas en el presente informe corresponde a una selección priorizada en función a la importancia de optimizar el recurso hídrico en el ámbito de estudio. 14. Geologic and hydrostratigraphic map of the Anhalt, Fischer, and Spring Branch 7.5-minute quadrangles, Blanco, Comal, and Kendall Counties, Texas Science.gov (United States) Clark, Allan K.; Robert R. Morris, 2015-01-01 This report describes the geology and hydrostratigraphy of the Edwards and Trinity Groups in the Anhalt, Fischer, and Spring Branch 7.5-minute quadrangles, Blanco, Comal, and Kendall Counties, Texas. The hydrostratigraphy was defined based on variations in the amount and type of porosity of each lithostratigraphic unit, which varies depending on the unit’s original depositional environment, lithology, structural history, and diagenesis. 15. Multi-disciplinary organization for the completion and start-up of the Laguna Verde-2 power reactor International Nuclear Information System (INIS) 1995-01-01 The optimization of the human and material resources for the pre-operational tests in the Laguna Verde-2 nuclear plant is described. About three thousand specialist of different groups were involved and each one had its own routines and functions with a complicated communication system among them. The optimization aimed at integrating and coordinating the organizational resources and defining the goals to be reached 16. 15 years of production of electric energy of the Laguna Verde power plant, its plans and future; 15 anos de produccion de energia electrica de la Central Laguna Verde, sus planes y futuro Energy Technology Data Exchange (ETDEWEB) Rivera C, A [CFE, Central Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico) 2005-07-01 In the year 2005 Laguna Verde power plant reaches 15 years of producing electric power in Mexico arriving to but of 100 million Megawatts-hour from their beginning of commercial activities. The Unit 1 that entered at July 29, 1990 and the Unit 2 at April 10, 1995, obtaining the Disposability Factors from their origin is: 84.63% in Unit 1 and 83.67% in Unit 2. The march of the X XI century gives big challenges of competition to the Laguna Verde Central, with the possible opening of the electric market to private investment, for their Goals and Objectives of a world class company, taking the evaluation system and qualification of the World Association of Nuclear Operators (WANO) that promotes the Excellence in the operation of the nuclear power stations in all their partners. This Association supports the development of programs that allow the monitoring of the behavior in Safety Culture, Human fulfilment, Equipment reliability, Industrial Safety, Planning, Programming and Control, Personalized Systematic Training, and the use of the Operational experience in the daily tasks. The present work tries to explain the system of evaluation/qualification of WANO, the definition of Goals and Objectives to reach the excellence and of the programs, it will present the Program of the Reliability of Equipment with its main actions the productivity. (Author) 17. Modernization of the Electric Power Systems (transformers, rods and switches) in the Laguna Verde Nuclear Power Plant (Mexico); Modernizacion de los Sistemas Electricos de Potencia (Transformadores de Principales, Interruptor de Generacion, Barras de Fase Aislada) de la Central Nuclear de Laguna Verde (Mexico) Energy Technology Data Exchange (ETDEWEB) Gonzalez Solarzano, J. J.; Gabaldon Martin, M. A.; Pallisa Nunez, J.; Florez Ordeonez, A.; Fernandez Corbeira, A.; Prieto Diez, I. 2010-07-01 Description of the changes made in the Electric Power Systems as a part of the power increase project in the Laguna Verde Nuclear Power Plant (Mexico). The main electrical changes to make, besides the turbo group, are the main generation transformers, the isolated rods and the generation switch. 18. The National Institute of Nuclear Research (ININ) and its participation in the External Radiological Emergency Plans at Laguna Verde Power plant; El ININ y su participacion en el Plan de Emergencia Radiologica Externo de la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Suarez, G. [Instituto Nacional de Investigaciones Nucleares, Departamento de Proteccion Radiologica, A.P. 18-1027, 11801 Mexico D.F. (Mexico) 1998-07-01 In this article it is described the form in which the ININ participates in the External Radiological Emergency Plan at Laguna Verde Power plant. It is set the objective, mission and organization of this plan. The responsibilities and activities that plan has assigned are mentioned also the organization to fulfil them and the obtained results during 9 years of participation. (Author) 19. Dissolved organic nitrogen (DON) profile during backwashing cycle of drinking water biofiltration. Science.gov (United States) Liu, Bing; Gu, Li; Yu, Xin; Yu, Guozhong; Zhang, Huining; Xu, Jinli 2012-01-01 A comprehensive investigation was made in this study on the variation of dissolved organic nitrogen (DON) during a whole backwashing cycle of the biofiltration for drinking water treatment. In such a cycle, the normalized DON concentration (C(effluent)/C(influent)) was decreased from 0.98 to 0.90 in the first 1.5h, and then gradually increased to about 1.5 in the following 8h. Finally, it remained stable until the end of this 24-hour cycle. This clearly 3-stage profile of DON could be explained by three aspects as follows: (1) the impact of the backwashing on the biomass and the microbial activity; (2) the release of soluble microbial products (SMPs) during the biofiltration; (3) the competition between heterotrophic bacteria and nitrifying bacteria. All the facts supported that more DON was generated during later part of the backwashing cycle. The significance of the conclusion is that the shorter backwashing intervals between backwashing for the drinking water biofilter should further decrease the DON concentration in effluent of biofilter. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved. 20. Nevus blanco esponjoso familiar Family nevus spongiosus albus Directory of Open Access Journals (Sweden) Mônica Andrade Lotufo 2010-06-01 Full Text Available El nevus blanco esponjoso (NBE es una rara condición autosómica dominante, caracterizada por placas blancas bilaterales en la mucosa, de aspecto esponjoso, blandas a la palpación y que pueden escamarse. Los tratamientos son paliativos; y el uso de antibióticos, en especial la tetraciclina, ha demostrando buenos resultados en su control. Este trabajo presenta tres casos clínicos de una familia afectada por NBE, donde se discuten los posibles diagnósticos diferenciales y conductas terapéuticas indicadas. Un paciente masculino de 52 años de edad acudió a la clínica aquejado de lesiones blancas bilaterales. El paciente notó las lesiones 30 años antes, sin lograr un diagnóstico final de las mismas. Después de la anamnesis y del examen clínico fue realizada una biopsia incisional. La reunión de los datos clínicos e histopatológicos llevó al diagnóstico de NBE. Se le solicitó al paciente que indagase entre sus familiares con respecto a lesiones semejantes. Se detectó que el hijo de 19 años y la hija de 25 eran portadores de placas blancas en la mucosa yugal. Como no había afectación estética, se optó por no intervenir en las lesiones. El nevus blanco esponjoso es una lesión genética que debe ser diferenciada de otras patologías localizadas y sistémicas importantes, que tienen repercusiones serias para el individuo. Como no hay un tratamiento curativo para el NBE, el papel del cirujano dentista es diagnosticar esta lesión, aclarar al paciente sobre la naturaleza benigna y autolimitante del NBE y si fuera necesario desde el punto de vista estético, aplicar diferentes modalidades terapéuticas.The aim of present paper is to introduce three clinical cases from a family affected from nevus spongiosus albus (NSA and also to discuss the possible differential diagnoses as well as the therapeutical behaviors to be adopted. Clinical case: A man aged 52 seen in our clinic due to bilateral white lesions noted 30 years ago without 1. Strategic planning 2007-2011, an opportunity for quality, competitiveness and excellence of the Laguna Verde Central International Nuclear Information System (INIS) Rivera C, A. 2007-01-01 The reason is to give to know to the nuclear community in Mexico the good results that it located in the 2006 to the Laguna Verde Nucleo electric Central in the classification of the World Association of Nuclear Operators (WANO) like one of the best in the worldwide scale, and their Strategic Plan 2007-2011 like an opportunity to continue improving the Quality, the Competitiveness and the Excellency in their Generating Units. It stands out that the fuel reloads are carried out in systemic form in less than 30 days, and also other achievements like it is the certificate granted by PROFEPA of Clean Industry, the renovation of the Certifications of the ISO-9001 and the ISO-14001, as well as the accredit of the Laboratories, and they will give data of the project of the increment of power that their power rose in 15%. For those results in the Strategic Planning 2007-2011 are pointed out that the Laguna Verde Central is a highly viable option in Mexico, when continuing with reloads that will allow a capacity factor up of 90%, and the other concepts that will give the obtaining of the qualification level 1 of WANO in this strategic period. Finally I will conclude with the good news for the Nuclear Industry in Mexico that published the Reforma newspaper at November 01, 2006: 'To the president of Mexico, Felipe Calderon, interests him to impel during his command the alternating energy sources to the hydrocarbons, known it is that the hydrocarbons (petroleum, coal or natural gas) they are finite, while the appetite of the world for the energy is infinite. As you they know, Mexico possesses a nuclear plant that generates energy starting from enriched uranium: the famous Laguna Verde Thermonuclear Central. He declared that Mexico can and it should advance for the one on the way to the energy generation for the nuclear road.' (Author) 2. Participation of the ININ in the external radiological emergency plan of the Laguna Verde power plant International Nuclear Information System (INIS) Martinez S, R.; Cervini L, A. 1991-01-01 The planning of performances in radiological emergencies, with the object of reducing the consequences as much as possible on the population to accidental liberations of radioactive material coming from Nuclear power plant, it has been of main interest in the nuclear community in the world. In Mexico it has not been the exception, since with the setting in march of the Laguna Verde nuclear power plant exists an executive program of planning for emergencies that it outlines the activities to follow trending to mitigate the consequences that are derived of this emergency. As integral part of this program this the External Plan of Radiological Emergency (PERE) that covers the emergencies that could leave the frontiers of the Laguna Verde power plant. In the PERE it settles down the planning, address and control of the preparation activities, response and recovery in emergencies, as well as the organization and coordination of the institutions that participate. The National Institute of Nuclear Research (ININ), like integral part of these institutions in the PERE, has an infrastructure that it allows to participate in the plan in a direct way in the activities of 'Control of the radiological exhibition the response personnel and control of water and foods' and of support way and consultant ship in the activities of 'Monitoring, Classification and decontamination of having evaluated' and 'Specialized medical radiological attention'. At the moment the ININ has a radiological mobile unit and this conditioning a second mobile unit to carry out part of the activities before mentioned; also accounts with 48 properly qualified people that directly intervene in the plan. In order to guarantee an adequate response in the PERE an organization it has been structured like that of the annex as for the personnel, transport, team, procedures and communication system, with the objective always of guaranteeing the security and the population's health in emergency situations in the 3. An aerial radiological survey of the project Rio Blanco and surrounding area International Nuclear Information System (INIS) Singman, L.V. 1994-11-01 A team from the Remote Sensing Laboratory in Las Vegas, Nevada, conducted an aerial radiation survey of the area surrounding ground zero of Project Rio Blanco in the northwestern section of Colorado in June 1993. The object of the survey was to determine if there were man-made radioisotopes on or near the surface resulting from a nuclear explosion in 1972. No indications of surface contamination were found. A search for the cesium-137 radioisotope was negative. The Minimum Detectable Activity for cesium-137 is presented for several detection probabilities. The natural terrestrial exposure rates in units of Roentgens per hour were mapped and are presented in the form of a contour map over-laid on an aerial photograph. A second team made independent ground-based measurements in four places within the survey area. The average agreement of the ground-based with aerial measurements was six percent 4. Pia Petersen sous le signe de don Quichotte Directory of Open Access Journals (Sweden) Esther Bautista Naranjo 2013-04-01 Full Text Available This interview has been motivated by the Cervantean intertextuality of Pia Petersen’s (a French-speaking Danish author last novel, Le Chien de don Quichotte (2012. Departing from the values that the writer attributes to Cervantes’ work, I try to establish a connection with a specific critical trend in order to test, later on, to which extent this approach is used by the author to create a series of characters placed under the sign of don Quixote. Finally, I evaluate her novel’s relation with contemporary reality. 5. Lesbian, Gay, Bisexual, and Transgender (LGBT) Service Members: Life After Don't Ask, Don't Tell. Science.gov (United States) Goldbach, Jeremy T; Castro, Carl Andrew 2016-06-01 Lesbian, gay, and bisexual service members can serve openly in the military with the repeal of the Don't Ask, Don't Tell policy. The fate of transgender service members remains uncertain as the policy preventing them from serving in the military remains under review. The health care needs of these populations remain for the most part unknown, with total acceptance and integration in the military yet to be achieved. In this paper, we review the literature on the health care needs of lesbian, gay, bisexual, and transgender (LGBT) service members, relying heavily on what is known about LGBT civilian and veteran populations. Significant research gaps about the health care needs of LGBT service members are identified, along with recommendations for closing those gaps. In addition, recommendations for improving LGBT acceptance and integration within the military are provided. 6. MFS Transporters and GABA Metabolism Are Involved in the Self-Defense Against DON in Fusarium graminearum Directory of Open Access Journals (Sweden) Qinhu Wang 2018-04-01 Full Text Available Trichothecene mycotoxins, such as deoxynivalenol (DON produced by the fungal pathogen, Fusarium graminearum, are not only important for plant infection but are also harmful to human and animal health. Trichothecene targets the ribosomal protein Rpl3 that is conserved in eukaryotes. Hence, a self-defense mechanism must exist in DON-producing fungi. It is reported that TRI (trichothecene biosynthesis 101 and TRI12 are two genes responsible for self-defense against trichothecene toxins in Fusarium. In this study, however, we found that simultaneous disruption of TRI101 and TRI12 has no obvious influence on DON resistance upon exogenous DON treatment in F. graminearum, suggesting that other mechanisms may be involved in self-defense. By using RNA-seq, we identified 253 genes specifically induced in DON-treated cultures compared with samples from cultures treated or untreated with cycloheximide, a commonly used inhibitor of eukaryotic protein synthesis. We found that transporter genes are significantly enriched in this group of DON-induced genes. Of those genes, 15 encode major facilitator superfamily transporters likely involved in mycotoxin efflux. Significantly, we found that genes involved in the metabolism of gamma-aminobutyric acid (GABA, a known inducer of DON production in F. graminearum, are significantly enriched among the DON-induced genes. The GABA biosynthesis gene PROLINE UTILIZATION 2-2 (PUT2-2 is downregulated, while GABA degradation genes are upregulated at least twofold upon treatment with DON, resulting in decreased levels of GABA. Taken together, our results suggest that transporters influencing DON efflux are important for self-defense and that GABA mediates the balance of DON production and self-defense in F. graminearum. 7. Fuel elements assembling for the DON project exponential experience; Montaje de los elementos combustibles para la experiencia exponencial del proyecto DON Energy Technology Data Exchange (ETDEWEB) Anca Abati, R de 1966-07-01 It is described the fuel unit used in the DON exponential experience, the manufacturing installments and tools as well as the stages in the fabrication.These 74 elements contain each 19 cartridges loaded with synterized urania, uranium carbide and indium, gold, and manganese probes. They were arranged in calandria-like tubes and the process-tube. This last one containing a cooling liquid simulating the reactor organic. Besides being used in the DON reactor exponential experience they were used in critic essays by the substitution method in the French reactor AQUILON II. (Author) 6 refs. 8. Characterization of water and lake sediments in Laguna de Bay International Nuclear Information System (INIS) San Diego, Cherry Ann; Francisco, Pattrice Armynne; Navoa, Joshua Antonio; Johnson, Bryan; Dave, Harshil; Cryer, Karl; Panemanglor, Rajeev; Rama, Mariecar; Sucgang, Raymond J. 2011-01-01 In this work we studied elemental distributions of trace elements, dissolved oxygen and microbiological allotment (total plate count, Coliform, and E. coli) in sediment and surface water from 3 sites in Laguna de Bay. The measured parameters were associated with the quality of the water and to anthropogenic and geogenic processes taking place in the lake. In all cases sediment samples were collected and analyzed for elemental composition using an X-ray fluorescence technique. Water samples were collected and analyzed for nitrate, chloride, and sulfate ions using selective electrodes. Bicarbonate ions in the lake water were determined by titration. The microbial load (total plate count, total coliform and E,. Coli) were determined using Simplate. Field parameters such as pH and conductivity were likewise measured. Preliminary assumptions suggest that proximity to anthropogenic sources has substantially contributed to the combined loads of major ions pollution in the lake. Laguna de Bay is classified as Class C (DENR Administrative Order No. 34). For all the sites, the conductivity of the water were considerably elevated, which ranged from 929 to 933 uS/cm; Site 1 water exceeded the permissible range for pH for Class C water which is 6.5 to 8.5 for the support and rearing of fish. None of the lake waters exceeded the limits for the ions, chloride (set at 350 mg/L) and nitrate (set at 10 mg/L), for Class C water criteria. All the sites meet the dissolved oxygen, DO, criterion for Class C waters which is set at 5 mg/L. In terms of microbiological load, Site 1 had the least most probable number per ml of water, MPN/ml: total plate count (6720), Coliform (less that detection limit) and E. coli (less than LLD); Site 3 was the most contaminated: total plate count (greater than 70,000), Coliform(48768) and E. Coli (23808). X-ray fluorescence analyses of sediments allowed the determination of elements Na, Mg, Al, P, Si, Cl, K. Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, As, Br, Rb 9. Don Zhuanu otdajutsja tolko po ljubvi Index Scriptorium Estoniae 2006-01-01 Eestisse tuleb külla Roman Viktjuki Teater, 1. nov. mängitakse Vene Kultuurikeskuses Jean Genet' "Toatüdrukuid" (lavastaja Roman Viktjuk), 23. nov. etendatakse Eric-Emmanuel Scmitti "Don Juani viimast armastust" (lavastaja Roman Viktjuk) 10. Turbine model for the Laguna Verde nucleo electric central based in the RELAP code; Modelo de turbina para la Central nucleoelectrica de Laguna Verde basado en el codigo RELAP Energy Technology Data Exchange (ETDEWEB) Cortes M, F.S.; Ramos P, J.C.; Salazar S, E.; Chavez M, C. [Facultad de Ingenieria, Division de Estudios de Posgrado, Grupo de Ingenieria Nuclear, UNAM (Mexico)]. e-mail: [email protected] 2003-07-01 The Nuclear Power stations as Laguna Verde occupy at the present time a place every time but important as non pollutant alternative, economic and trusty to generate electricity. It is for it that the Group of Nuclear Engineering of the Engineering Faculty (GrlNFI) of the National Autonomous University of Mexico (UNAM) it develops investigation projects applied to Nuclear Centrals. One of the projects in process is the development of a Classroom simulator, which it can configures to consent to diverse models of nuclear systems with training purposes in normal operation, or, to consent to specialized nuclear codes for the analysis of transitory events and have a severe accident. This work describes the development, implementation and it proves of a simplified model of the Main turbine to be integrated to the group of models of the Classroom simulator. It is part of the current effort of GrlNFI guided to obtain a representation of all the dynamic models necessary to simulate the Plant Balance of the Laguna Verde Central. It is included the development of the unfolding graphic which represent the modeling of the Main turbine, and of the control interface that allows the user to manipulate in simple way, direct and interactive this device during the training or the analysis. With this work it is wanted to contribute to the training of new technicians and to support the operation personnel of the Centrals. Also, the developed infrastructure is guided to contribute in the design and analysis of new Nuclear Power stations with the contribution of new computational tools for the visualization, simulation and process control. (Author) 11. Modernization of electric power systems of the Laguna Verde Nuclear Power Plant International Nuclear Information System (INIS) Gabaldon, M. A.; Gonzalez, J. J.; Prieto, I. 2011-01-01 The Power Increase Project of Laguna Verde Nuclear Plant has entailed the replacement, in one unique outage, of the main power electrical systems of the Plant (Isolated Phase Bars, Generator Circuit Breaker and Main Transformer) as well as the replacement of the Turbo-group. The simultaneous substitution of these entire system has never been done by any other Plant in the world, representing an engineering challenge that embraced the design of the new equipment up to the planning, coordination and management of the construction and commissioning works, which were successfully carried out by Iberdrola within the established outage period /47 days) for both units. (Author) 12. Don't Take This with That! Medline Plus Full Text Available ... Tobacco Products Drugs Home Drugs Resources for You Special Features Don't take this with that! Share ... Drug Interactions: What You Should Know More in Special Features Page Last Updated: 12/17/2015 Note: ... 13. El impacto de la desecación de la laguna de Lerma en la gastronomía lacustre de San Pedro Tultepec de Quiroga, Estado de México Directory of Open Access Journals (Sweden) Felipe Carlos Viesca González 2011-01-01 Full Text Available El objetivo de este trabajo es caracterizar la gastronomía lacustre en el Alto Lerma, prevaleciente antes y después de la desecación de la Laguna de Lerma, específicamente la de San Pedro Tultepec de Quiroga municipio de Lerma, en el Estado de México. Mediante la aplicación de la técnica etnográfica en la realización de la investigación de campo, se identificaron y localizaron a 30 personas adultas que aún entran a la laguna de Chimaliapan o Lerma, o que tienen conocimiento sobre los ingredientes lacustres y las preparaciones culinarias elaboradas con ellos. Además se realizaron visitas a los mercados locales e incursiones en la laguna y áreas aledañas con la guía de lugareños conocedores del entorno, con el fin de obtener información sobre estos productos. Se encontró que todavía se recolectan especies vegetales como nopales, hongos, papas de agua o apacloles y quelites, entre ellos berros o tiernitos y quintoniles. Asimismo, se aprovechan especies animales como patos, carpas, atepocates, ranas, acociles y ajolotes. Menos del 1% de la población estudiada aún elabora platillos basados en ingredientes extraídos de la laguna. Se preparan tamales de pescado, rana o carpa, acociles, hueva de carpa, carpas y patos de diversas maneras, chile relleno de támbulas y atepocates, y ranas empanizadas o fritas. Con base en lo anterior, se concluye, que a pesar de estar contaminada, todavía se extrae de la laguna de Chimaliapan una gran variedad de flora y fauna que se emplea para la alimentación, lo cual indica que estos recursos bióticos son una importante fuente para muchas familias, y que tienen un "buen potencial" de aprovechamiento. 14. Kulturel liminalitet i Don Quixote DEFF Research Database (Denmark) Fastrup, Anne 2007-01-01 Med udgangspunkt i og i kontrast til nogle af hovedlinierne i den nyere litteratur om Don Quixote søger artiklen tilbage til de mere specifikke og lokale historiske forhold, som er romanens baggrund, bl.a. til Cervantes' »algierske erfaring« med tyrkisk fangenskab. Artiklen forsøger at kombinere ... 15. Salt lake Laguna de Fuente de Piedra (S-Spain) as Late Quaternary palaeoenvironmental archive Science.gov (United States) Höbig, Nicole; Melles, Martin; Reicherter, Klaus 2014-05-01 This study deals with Late Quaternary palaeoenvironmental variability in Iberia reconstructed from terrestrial archives. In southern Iberia, endorheic basins of the Betic Cordilleras are relatively common and contain salt or fresh-water lakes due to subsurface dissolution of Triassic evaporites. Such precipitation or ground-water fed lakes (called Lagunas in Spanish) are vulnerable to changes in hydrology, climate or anthropogenic modifications. The largest Spanish salt lake, Laguna de Fuente de Piedra (Antequera region, S-Spain), has been investigated and serves as a palaeoenvironmental archive for the Late Pleistocene to Holocene time interval. Several sediment cores taken during drilling campaigns in 2012 and 2013 have revealed sedimentary sequences (up to 14 m length) along the shoreline. A multi-proxy study, including sedimentology, geochemistry and physical properties (magnetic susceptibility) has been performed on the cores. The sedimentary history is highly variable: several decimetre thick silty variegated clay deposits, laminated evaporites, and even few-centimetre thick massive gypsum crystals (i.e., selenites). XRF analysis was focussed on valuable palaeoclimatic proxies (e.g., S, Zr, Ti, and element ratios) to identify the composition and provenance of the sediments and to delineate palaeoenvironmental conditions. First age control has been realized by AMS-radiocarbon dating. The records start with approximately 2-3 m Holocene deposits and reach back to the middle of MIS 3 (GS-3). The sequences contain changes in sedimentation rates as well as colour changes, which can be summarized as brownish-beige deposits at the top and more greenish-grey deposits below as well as highly variegated lamination and selenites below ca. 6 m depth. The Younger Dryas, Bølling/Allerød, and the so-called Mystery Interval/Last Glacial Maximum have presumably been identified in the sediment cores and aligned to other climate records. In general, the cores of the Laguna de 16. Geology and metallogeny of the volcanic complex of Rio Blanco Ullum. Province of San Juan. Republica Argentina International Nuclear Information System (INIS) Mendoza, N.; Weidmann, N.; Puigdomenech, H.; Weidmann, R. 2007-01-01 Preliminary results of a research carried out at the Complejo Rio Blanco de Ullum, San Juan. Argentina are summarized in the present paper. These studies are focused on geological and metallogenic features o f this unit. The study area is located 20 km. WNW of San Juan city with geographic coordinates of 31grades 30' South latitude and 68 grades 52' West longitude. The older rocks aotcroping in the area correspond to limestones of Ordovician San Juan Formation, the chronologic succession continues with sales and siltstones of Silurian Tambolar Formation, pelites and subgraywackes of Devonian Punta Negra Formation and finally a 1500 m thick package of piroclastics and sediments of Albarracin Formation of Tertiary age. Albarracin Formation is composed pf a Basal Member (sandstones and stilstones), a Tuffaceous Member (tuffs, tuffites and oligomictic breccia s with conglomerate interbed dings in the upper part) and a Conglomeratic Member (polimictic para conglomerates). According to piroclastics facies, relationships and spreading area of piroclastics deposits a c olapsed dome and avalanche model is proposed to be the main process for the piroclastics package outcropping in the area.Sedimentary and piroclastics rocks are intruded by five sub volcanic units as noted by Leveratto (1968) which are composed by different lithologies such as: Altered Da cite - Rhyolite, Ullum Da cite, Cerro Blanco de Zonda Andesite, Ullum Andesite and Hybrid Andesite.Detailed work on alteration assemblages and metallogenic features in the southwestern sector of the Complejo resulted in the identification of three alteration zones with characteric features of potassic, argillic and propyllitic signature. (author) 17. Rethinking the Role of Development Banks in Climate Finance: Panama’s Barro Blanco CDM Project and Human Rights Directory of Open Access Journals (Sweden) Beatriz Felipe Pérez 2016-06-01 Full Text Available Development banks are key actors in climate finance. During the last decades, they have increased the funding of climate change related projects, especially those under the Clean Development Mechanism (CDM. Defined in Article 12 of the Kyoto Protocol, the CDM aims at contributing to climate change mitigation while assisting in achieving sustainable development. However, many CDM projects have caused environmental damage and human rights abuses that especially affect the most vulnerable people. Located in Panama, the Barro Blanco hydro-power dam exemplifies the complex interrelationship of climate financing, development policies, the political and economic national context and human rights. Through the analysis of the role of development banks in climate finance, especially in the context of CDM projects, this paper aims (1 to clarify the role of development banks in climate finance, (2 to shed light on the vulnerable situation of the people affected by these projects, (3 to highlight the gaps in both the CDM rules and the development banks’ safeguard policies concerning the protection of human rights and the prevention of environmental abuses, and (4 to give a current example of this complex situation through the Barro Blanco case study. This paper argues that the manifold and often competing national and international legal and political layers of climate change mitigation projects repeatedly leave project affected people vulnerable to human rights violations without adequate safeguards and mechanisms to effectively articulate their interests, protect their rights and promote access to justice. 18. Comparison of predicted and observed pore pressure increases on Rio Blanco International Nuclear Information System (INIS) Banister, J.R.; Ellett, D.M.; Pyke, R.; Winters, L. 1976-01-01 The RIO BLANCO event presented the opportunity to monitor, under controlled conditions in the field, the increase in pore pressures resulting from ground motion similar to an earthquake. In situ measurements of pore pressure changes were made by Sandia Laboratories and Dames and Moore. This report contains the results of laboratory tests believed to be indicative in assessing the magnitude of pore pressure increases and probability of soil liquefaction. These include triaxial load tests, gradation of grain size, and relative density. No liquefaction was observed in the field, and the increase of in situ pore pressures were much less than expected from laboratory measurements. Allied subjects presented in this report are pore pressure propagation and dissipation profiles, the previously unpublished pore pressure measurements made by Dames and Moore, and the boring logs for the various sites where measurements were taken. It is concluded that methods used to predict pore pressure increases and liquefaction potential are overly conservative, at least for these alluvial and colluvial soils found in Colorado 19. Don't Take This with That! Medline Plus Full Text Available ... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Drugs Home Drugs Resources for You Special Features Don't take ... worth the squeeze…especially when combining grapefruit with medicines. While it can be part of a balanced ... 20. Don't Take This with That! Medline Plus Full Text Available ... Español Search FDA Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Drugs Home Drugs Resources for You Special Features Don't ... 1. Origin and evolution of the Laguna Potrok Aike maar (Southern Patagonia, Argentina) as revealed by seismic data Science.gov (United States) Gebhardt, C.; de Batist, M. A.; Niessen, F.; Anselmetti, F.; Ariztegui, D.; Haberzettl, T.; Ohlendorf, C.; Zolitschka, B. 2009-12-01 Seismic reflection and refraction data provide insights into the sedimentary infill and the underlying volcanic structure of Laguna Potrok Aike, a maar lake situated in the Pali Aike Volcanic Field, Southern Patagonia. The lake has a diameter of ~3.5 km, a maximum water depth of ~100 m and a presumed age of ~770 ka. Its sedimentary regime is influenced by climatic and hydrologic conditions related to the Antarctic Circumpolar Current, the Southern Hemispheric Westerlies and sporadic outbreaks of Antarctic polar air masses. Multiproxy environmental reconstructions of the last 16 ka document that this terminal lake is highly sensitive to climate change. Laguna Potrok Aike has recently become a major focus of the International Continental Scientific Drilling Program and was drilled down to 100 m below lake floor in late 2008 within the PASADO project. The sediments are likely to contain a continental record spanning the last ca. 80 kyrs unique in the South American realm. Seismic reflection data show relatively undisturbed, stratified lacustrine sediments at least in the upper ~100 m of the sedimentary infill but are obscured possibly by gas and/or coarser material in larger areas. A model calculated from seismic refraction data reveals a funnel-shaped structure embedded in the sandstone rocks of the surrounding Santa Cruz Formation. This funnel structure is filled by lacustrine sediments of up to 370 m in thickness. These can be separated into two distinct subunits with low acoustic velocities of 1500-1800 m s-1 in the upper subunit pointing at unconsolidated lacustrine muds, and enhanced velocities of 2000-2350 m s-1 in the lower subunit. Below these lacustrine sediments, a unit of probably volcanoclastic origin is observed (>2400 m s-1). This sedimentary succession is well comparable to other well-studied sequences (e.g. Messel and Baruth maars, Germany), confirming phreatomagmatic maar explosions as the origin of Laguna Potrok Aike. 2. Groundwater flow in a closed basin with a saline shallow lake in a volcanic area: Laguna Tuyajto, northern Chilean Altiplano of the Andes. Science.gov (United States) Herrera, Christian; Custodio, Emilio; Chong, Guillermo; Lambán, Luis Javier; Riquelme, Rodrigo; Wilke, Hans; Jódar, Jorge; Urrutia, Javier; Urqueta, Harry; Sarmiento, Alvaro; Gamboa, Carolina; Lictevout, Elisabeth 2016-01-15 Laguna Tuyajto is a small, shallow saline water lake in the Andean Altiplano of northern Chile. In the eastern side it is fed by springs that discharge groundwater of the nearby volcanic aquifers. The area is arid: rainfall does not exceed 200mm/year in the rainiest parts. The stable isotopic content of spring water shows that the recharge is originated mainly from winter rain, snow melt, and to a lesser extent from some short and intense sporadic rainfall events. Most of the spring water outflowing in the northern side of Laguna Tuyajto is recharged in the Tuyajto volcano. Most of the spring water in the eastern side and groundwater are recharged at higher elevations, in the rims of the nearby endorheic basins of Pampa Colorada and Pampa Las Tecas to the East. The presence of tritium in some deep wells in Pampa Colorada and Pampa Las Tecas indicates recent recharge. Gas emission in recent volcanoes increase the sulfate content of atmospheric deposition and this is reflected in local groundwater. The chemical composition and concentration of spring waters are the result of meteoric water evapo-concentration, water-rock interaction, and mainly the dissolution of old and buried evaporitic deposits. Groundwater flow is mostly shallow due to a low permeability ignimbrite layer of regional extent, which also hinders brine spreading below and around the lake. High deep temperatures near the recent Tuyajto volcano explain the high dissolved silica contents and the δ(18)O shift to heavier values found in some of the spring waters. Laguna Tuyajto is a terminal lake where salts cumulate, mostly halite, but some brine transfer to the Salar de Aguas Calientes-3 cannot be excluded. The hydrogeological behavior of Laguna Tuyajto constitutes a model to understand the functioning of many other similar basins in other areas in the Andean Altiplano. Copyright © 2015 Elsevier B.V. All rights reserved. 3. Salida de campo a Laguna de Duero (Valladolid) el 14 de febrero de 1951 OpenAIRE Valverde Gómez, José Antonio, 1926-2003 2008-01-01 Salida de campo a Laguna de Duero, en la provincia de Valladolid, durante la mañana del 14 de febrero de 1951, de la que se anotaron observaciones sobre las siguientes aves: Accipiter nisus (Gavilán común, también llamado Astur palumbarius por el autor), Anas penelope (Silbón europeo), Anas platyrhynchos (Ánade azulón), Anser anser (Ánsar común), Anthus sp. (Bisbita), Ciconia ciconia (Cigüeña blanca), Clamator glandarius (Críalo europeo), Coccothraustes coccothraustes (Picogordo), Corvus coro... 4. Don't Take This with That! Medline Plus Full Text Available ... Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Drugs Home Drugs Resources for You Special Features Don't take ... more than fifty prescription and over-the-counter drugs known to the U.S. Food and Drug Administration ... 5. Influence of a carp invasion on the zooplankton community in Laguna Medina, a Mediterranean shallow lake OpenAIRE Norbert, Florian; López-Luque, raquel; Ospina-Álvarez, Natalia; Hufnagel, Levente; Green, Andy J. 2016-01-01 The common carp (Cyprinus carpio) is a highly invasive species and an ecological engineer. It has been repeatedly shown to increase nutrient concentrations and phytoplankton biomass while destroying submerged macrophytes, although there are few studies from the Mediterranean region. We studied its impact on the zooplankton community in Laguna de Medina lake, a shallow lake in Jerez de la Frontera, south-west Spain. Carp were removed with rotenone in 2007 but returned in 2010-2011. ... 6. DON JUAN: THE DISCOURSE OF SEDUCTION AS AN EXERCISE OF POWER Directory of Open Access Journals (Sweden) Kristina Stankevičiūtė 2016-10-01 Full Text Available The figure of Don Juan that emerged in Spanish baroque synthesised several important cultural issues related to the phenomenon of seduction, a subject of great social controversy since the very beginning of the Christian era. The present article analyses one of the fundamental parts of the universal appeal of the Don Juan figure – the discourse of seduction, considering it from the social and cultural point of view. The traditional discussion of the subject focuses on the contents of the discourse whereas the present article emphasises the implications rather than the contents, grounding its arguments on Jean Baudrillard’s theory of seduction, which claims that it is the signs and the play of signs that are important in seduction, not their meanings. The seduction discourse is seen as a means to exercise power on the women that Don Juan deals with as well as on the audience who gets involved into the discourse creation process. The article concludes with a claim that Don Juan is a figure of social domination, and his discourse is a means to achieve it. 7. Diversidad de géneros de hongos del suelo en tres campos con diferente condición agrícola en La Laguna, México Diversity of soil fungi genera in three different condition agricultural fields in La Laguna, Mexico Directory of Open Access Journals (Sweden) José Alfredo Samaniego-Gaxiola 2007-12-01 Full Text Available En La Laguna, Coahuila-Durango, México (zona con una precipitación anual entre 80 a 250 mm se estudió la estructura de géneros de hongos del suelo en 3 campos de cultivo agrícola. Del suelo de Tierra Blanca, una huerta de nogal de 51 años, fueron aislados 23 géneros de hongos y de otros 2 suelos, una huerta de nogal de 14 años, nombrada El Chupón y un campo con cultivo de alfalfa, denominado San Jorge, se aislaron l2 géneros. Para cada género se calculó su valor índice de ímportancia (V I I. El género Fusarium tuvo el mayor V I I en los 3 suelos estudiados (71-98. La diversidad (calculada con el índice de Shannon de géneros fue diferente para cada suelo de acuerdo con intervalos de confianza (95%, con valores de 1.89, 1.72 y 1.19 para Tierra Blanca, El Chupón y San Jorge, respectivamente. Se calcularon índices ecológicos adicionales, como, Simpson, máxima riqueza (H' max y regularidad (J'. Los valores del índice de Simpson y de J' fueron similares en Tierra Blanca y San Jorge, pero sólo H' max fue similar entre El Chupón y San Jorge. El índice de similitud de Shøresen fue igual al comparar Tierra Blanca con El Chupón o Tierra Blanca con San Jorge (51.4, pero distinto entre el Chupón y San Jorge (58.3. El índice β para las combinaciones Tierra Blanca vs. San Jorge y Tierra Blanca vs. El Chupón fueron de 0.43, pero para San Jorge vs. El Chupón fue de 0.83. Los géneros de hongos del suelo que se encontraron en La Laguna coinciden en 67-75% con los encontrados en suelos desérticos de Israel, pero en La Laguna la estructura de los géneros de hongos es distinta; aquí domina Fusarium y aparecen nuevos géneros, como Trichoderma. Los cambios en la micobiota del suelo pueden haber ocurrido por la actividad agrícola en los últimos 50 años.This study was carried out in agricultural soils in La Laguna, Coahuila - Durango, Mexico (annual precipitation 80-250 mm. The structure of soil fungal genera of three field soil 8. Cambios en el régimen hídrico de la laguna Lasuntay y Chuspicocha por variaciones en el Nevado Huaytapallana Directory of Open Access Journals (Sweden) Jacinto Arroyo Aliaga 2011-12-01 Full Text Available Objetivos: Estimar los efectos de las variaciones de torrentes de agua de los glaciares del Nevado Huaytapallana que emanan al sistema hídrico de las lagunas de Lasuntay y Chuspicocha. Métodos: Se utilizó el método general teórico deductivo de nivel explicativo, con un diseño no experimental del tipo transversal en el tratamiento de información; como método específico se ha utilizado el balance de masa del glaciar para el cálculo de volúmenes de agua de los torrentes a partir de la instalación de una red de balizas en la mayor parte del glaciar y en la zona de acumulación y ablación se excavaron pozos mediante perforaciones para medir directamente la cantidad de nieve acumulada entre el inicio y el fin del año hidrológico. Resultados: Se ha estimado los torrentes de caudal de agua que emanan del nevado Huaytapallana a las lagunas de Lasuntay y Chuspicocha en 1 226 700 m3 en la estación de verano; y de 245 340 m3 en la estación de primavera. Conclusiones: El volumen máximo de acumulación en ambas lagunas fue en el verano y el volumen mínimo en la estación de primavera, debido a las variaciones en el régimen hídrico del sistema de acumulación y ablación que afectan la disponibilidad de agua. 9. Embryotoxicity Caused by DON-Induced Oxidative Stress Mediated by Nrf2/HO-1 Pathway Directory of Open Access Journals (Sweden) Miao Yu 2017-06-01 Full Text Available Deoxynivalenol (DON belongs to the type B group of trichothecenes family, which is composed of sesquiterpenoid metabolites produced by Fusarium and other fungi in grain. DON may cause various toxicities, such as cytotoxicity, immunotoxicity, genotoxicity as well as teratogenicity and carcinogenicity. In the present study, we focus on a hypothesis that DON alters the expressions of Nrf2/HO-1 pathway by inducing embryotoxicity in C57BL/6 mouse (5.0, 2.5, 1.0, and 0 mg/kg/day and BeWo cell lines (0 and 50 nM; 3 h, 12 h and 24 h. Our results indicate that DON treatment in mice during pregnancy leads to ROS accumulation in the placenta, which results in embryotoxicity. At the same time Nrf2/HO-1 pathway is up-regulated by ROS to protect placenta cells from oxidative damage. In DON-treated BeWo cells, the level of ROS has time–effect and dose–effect relationships with HO-1 expression. Moderate increase in HO-1 protects the cell from oxidative damage, while excessive increase in HO-1 aggravates the oxidative damage, which is called in some studies the “threshold effect”. Therefore, oxidative stress may be the critical molecular mechanism for DON-induced embryotoxicity. Besides, Nrf2/HO-1 pathway accompanied by the “threshold effect” also plays an important role against DON-induced oxidative damage in this process. 10. Laguna Madre Water Purification using Biochar from Citrus Peels Science.gov (United States) Lopez, C.; Al-Qudah, O. M. 2017-12-01 Laguna Madre is an important lagoon in the coast of Texas. It is one of the seven hypersaline lagoons in the world. Due to inflow of water with extreme amounts of phosphorus and nitrates and the low inflow of freshwater, the lagoon has high amount of phosphorus and nitrates which can be harmful for fish and plants situated in the lagoon. The goal is to be able to perform a filtration method with citrus peels biochar, and then to evaluate and compare the produced biochar, zeolite, and activated carbon as an infiltration filter by assessing reductions of nitrogen and phosphorus compounds, as well as sum selected trace elements. Furthermore, the current research will investigate how long the cleaning capacity of biochar lasts and how the performance of the filter changes under an increased load of contaminants. The performance of biochar from different parent materials and recycling options for the used filter materials are also included in this research. 11. Selected Hydrologic, Water-Quality, Biological, and Sedimentation Characteristics of Laguna Grande, Fajardo, Puerto Rico, March 2007-February 2009 Science.gov (United States) Soler-López, Luis R.; Santos, Carlos R. 2010-01-01 Laguna Grande is a 50-hectare lagoon in the municipio of Fajardo, located in the northeasternmost part of Puerto Rico. Hydrologic, water-quality, and biological data were collected in the lagoon between March 2007 and February 2009 to establish baseline conditions and determine the health of Laguna Grande on the basis of preestablished standards. In addition, a core of bottom material was obtained at one site within the lagoon to establish sediment depositional rates. Water-quality properties measured onsite (temperature, pH, dissolved oxygen, specific conductance, and water transparency) varied temporally rather than areally. All physical properties were in compliance with current regulatory standards established for Puerto Rico. Nutrient concentrations were very low and in compliance with current regulatory standards (less than 5.0 and 1.0 milligrams per liter for total nitrogen and total phosphorus, respectively). The average total nitrogen concentration was 0.28 milligram per liter, and the average total phosphorus concentration was 0.02 milligram per liter. Chlorophyll a was the predominant form of photosynthetic pigment in the water. The average chlorophyll-a concentration was 6.2 micrograms per liter. Bottom sediment accumulation rates were determined in sediment cores by modeling the downcore activities of lead-210 and cesium-137. Results indicated a sediment depositional rate of about 0.44 centimeter per year. At this rate of sediment accretion, the lagoon may become a marshland in about 700 to 900 years. About 86 percent of the community primary productivity in Laguna Grande was generated by periphyton, primarily algal mats and seagrasses, and the remaining 14 percent was generated by phytoplankton in the water column. Based on the diel studies the total average net community productivity equaled 5.7 grams of oxygen per cubic meter per day (2.1 grams of carbon per cubic meter per day). Most of this productivity was ascribed to periphyton and macrophytes 12. Characterization of hydrology and water quality of Piceance Creek in the Alkali Flat area, Rio Blanco County, Colorado, March 2012 Science.gov (United States) Thomas, Judith C. 2015-12-07 Previous studies by the U.S. Geological Survey identified Alkali Flat as an area of groundwater upwelling, with increases in concentrations of total dissolved solids, and streamflow loss, but additional study was needed to better characterize these observations. The U.S. Geological Survey, in cooperation with the Bureau of Land Management, White River Field Office, conducted a study to characterize the hydrology and water quality of Piceance Creek in the Alkali Flat area of Rio Blanco County, Colorado. 13. Don't Take This with That! Medline Plus Full Text Available ... Submit search Popular Content Home Food Drugs Medical Devices Radiation-Emitting Products Vaccines, Blood & Biologics Animal & Veterinary Cosmetics Tobacco Products Drugs Home Drugs Resources for You Special Features Don't take this with that! Share Tweet Linkedin Pin it ... 14. El impacto de la desecación de la laguna de Lerma en la gastronomía lacustre de San Pedro Tultepec de Quiroga, Estado de México OpenAIRE Felipe Carlos Viesca González 2011-01-01 El objetivo de este trabajo es caracterizar la gastronomía lacustre en el Alto Lerma, prevaleciente antes y después de la desecación de la Laguna de Lerma, específicamente la de San Pedro Tultepec de Quiroga municipio de Lerma, en el Estado de México. Mediante la aplicación de la técnica etnográfica en la realización de la investigación de campo, se identificaron y localizaron a 30 personas adultas que aún entran a la laguna de Chimaliapan o Lerma, o que tienen conocimiento sobre los ingredie... 15. 77 FR 64973 - Don W. Gilbert Hydro Power, LLC; Notice of Application Accepted for Filing With the Commission... Science.gov (United States) 2012-10-24 ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14367-001] Don W. Gilbert...: Original Minor License. b. Project No.: 14367-001. c. Date filed: May 30, 2012. d. Applicant: Don W...(a)-825(r). (2006). h. Applicant Contact: Don W. Gilbert and DeAnn G. Somonich, Don W. Gilbert Hydro... 16. Physical Analysis of the Complex Rye (Secale cereale L.) Alt4 Aluminium (Aluminum) Tolerance Locus Using a Whole-Genome BAC Library of Rye cv. Blanco Science.gov (United States) Rye is a diploid crop species with many outstanding qualities, and is also important as a source of new traits for wheat and triticale improvement. Here we describe a BAC library of rye cv. Blanco, representing a valuable resource for rye molecular genetic studies. The library provides a 6 × genome ... 17. Mixing regime as a key factor to determine DON formation in drinking water biological treatment. Science.gov (United States) Lu, Changqing; Li, Shuai; Gong, Song; Yuan, Shoujun; Yu, Xin 2015-11-01 Dissolved organic nitrogen (DON) can act as precursor of nitrogenous disinfection by-products formed during chlorination disinfection. The performances of biological fluidized bed (continuous stirred tank reactor, CSTR) and bio-ceramic filters (plug flow reactor, PFR) were compared in this study to investigate the influence of mixing regime on DON formation in drinking water treatment. In the shared influent, DON ranged from 0.71mgL(-1) to 1.20mgL(-1). The two biological fluidized bed reactors, named BFB1 (mechanical stirring) and BFB2 (air agitation), contained 0.12 and 0.19mgL(-1) DON in their effluents, respectively. Meanwhile, the bio-ceramic reactors, labeled as BCF1 (no aeration) and BCF2 (with aeration), had 1.02 and 0.81mgL(-1) DON in their effluents, respectively. Comparative results showed that the CSTR mixing regime significantly reduced DON formation. This particular reduction was further investigated in this study. The viable/total microbial biomass was determined with propidium monoazide quantitative polymerase chain reaction (PMA-qPCR) and qPCR, respectively. The results of the investigation demonstrated that the microbes in BFB2 had higher viability than those in BCF2. The viable bacteria decreased more sharply than the total bacteria along the media depth in BCF2, and DON in BCF2 accumulated in the deeper media. These phenomena suggested that mixing regime determined DON formation by influencing the distribution of viable, total biomass, and ratio of viable biomass to total biomass. Copyright © 2014 Elsevier Ltd. All rights reserved. 18. Organ Damage and Hepatic Lipid Accumulation in Carp (Cyprinus carpio L. after Feed-Borne Exposure to the Mycotoxin, Deoxynivalenol (DON Directory of Open Access Journals (Sweden) Constanze Pietsch 2014-02-01 Full Text Available Deoxynivalenol (DON frequently contaminates animal feed, including fish feed used in aquaculture. This study intends to further investigate the effects of DON on carp (Cyprinus carpio L. at concentrations representative for commercial fish feeds. Experimental feeding with 352, 619 or 953 μg DON kg−1 feed resulted in unaltered growth performance of fish during six weeks of experimentation, but increased lipid peroxidation was observed in liver, head kidney and spleen after feeding of fish with the highest DON concentration. These effects of DON were mostly reversible by two weeks of feeding the uncontaminated control diet. Histopathological scoring revealed increased liver damage in DON-treated fish, which persisted even after the recovery phase. At the highest DON concentration, significantly more fat, and consequently, increased energy content, was found in whole fish body homogenates. This suggests that DON affects nutrient metabolism in carp. Changes of lactate dehydrogenase (LDH activity in kidneys and muscle and high lactate levels in serum indicate an effect of DON on anaerobic metabolism. Serum albumin was reduced by feeding the medium and a high dosage of DON, probably due to the ribotoxic action of DON. Thus, the present study provides evidence of the effects of DON on liver function and metabolism. 19. Organ Damage and Hepatic Lipid Accumulation in Carp (Cyprinus carpio L.) after Feed-Borne Exposure to the Mycotoxin, Deoxynivalenol (DON) Science.gov (United States) Pietsch, Constanze; Schulz, Carsten; Rovira, Pere; Kloas, Werner; Burkhardt-Holm, Patricia 2014-01-01 Deoxynivalenol (DON) frequently contaminates animal feed, including fish feed used in aquaculture. This study intends to further investigate the effects of DON on carp (Cyprinus carpio L.) at concentrations representative for commercial fish feeds. Experimental feeding with 352, 619 or 953 μg DON kg−1 feed resulted in unaltered growth performance of fish during six weeks of experimentation, but increased lipid peroxidation was observed in liver, head kidney and spleen after feeding of fish with the highest DON concentration. These effects of DON were mostly reversible by two weeks of feeding the uncontaminated control diet. Histopathological scoring revealed increased liver damage in DON-treated fish, which persisted even after the recovery phase. At the highest DON concentration, significantly more fat, and consequently, increased energy content, was found in whole fish body homogenates. This suggests that DON affects nutrient metabolism in carp. Changes of lactate dehydrogenase (LDH) activity in kidneys and muscle and high lactate levels in serum indicate an effect of DON on anaerobic metabolism. Serum albumin was reduced by feeding the medium and a high dosage of DON, probably due to the ribotoxic action of DON. Thus, the present study provides evidence of the effects of DON on liver function and metabolism. PMID:24566729 20. Estimation of fast neutron fluence in steel specimens type Laguna Verde in TRIGA Mark III reactor; Estimacion de la fluencia de neutrones rapidos en probetas de acero tipo Laguna Verde en el reactor Triga Mark III Energy Technology Data Exchange (ETDEWEB) Galicia A, J.; Francois L, J. L. [UNAM, Facultad de Ingenieria, Departamento de Sistemas Energeticos, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico); Aguilar H, F., E-mail: [email protected] [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico) 2015-09-15 The main purpose of this work is to obtain the fluence of fast neutrons recorded within four specimens of carbon steel, similar to the material having the vessels of the BWR reactors of the nuclear power plant of Laguna Verde when subjected to neutron flux in a experimental facility of the TRIGA Mark III reactor, calculating an irradiation time to age the material so accelerated. For the calculation of the neutron flux in the specimens was used the Monte Carlo code MCNP5. In an initial stage, three sheets of natural molybdenum and molybdenum trioxide (MoO{sub 3}) were incorporated into a model developed of the TRIGA reactor operating at 1 M Wth, to calculate the resulting activity by setting a certain time of irradiation. The results obtained were compared with experimentally measured activities in these same materials to validate the calculated neutron flux in the model used. Subsequently, the fast neutron flux received by the steel specimens to incorporate them in the experimental facility E-16 of the reactor core model operating at nominal maximum power in steady-state was calculated, already from these calculations the irradiation time required was obtained for values of the neutron flux in the range of 10{sup 18} n/cm{sup 2}, which is estimated for the case of Laguna Verde after 32 years of effective operation at maximum power. (Author) 1. Fuel elements assembling for the DON project exponential experience International Nuclear Information System (INIS) Anca Abati, R. de 1966-01-01 It is described the fuel unit used in the DON exponential experience, the manufacturing installments and tools as well as the stages in the fabrication.These 74 elements contain each 19 cartridges loaded with synterized urania, uranium carbide and indium, gold, and manganese probes. They were arranged in calandria-like tubes and the process-tube. This last one containing a cooling liquid simulating the reactor organic. Besides being used in the DON reactor exponential experience they were used in critic essays by the substitution method in the French reactor AQUILON II. (Author) 6 refs 2. Science 101: Why Don't Spiders Stick to Their Own Webs? Science.gov (United States) Robertson, Bill 2011-01-01 This article explains why spiders don't stick to their webs. Spiders don't get stuck in their own webs (and they aren't immune to their own glue) because they use a combination of sticky and nonsticky threads (different glands for producing those), and the glue is in droplets that the spider can avoid but the prey can't. The spider's nervous… 3. Microbial diversity and biomarker analysis of modern freshwater microbialites from Laguna Bacalar, Mexico. Science.gov (United States) Johnson, D B; Beddows, P A; Flynn, T M; Osburn, M R 2018-05-01 Laguna Bacalar is a sulfate-rich freshwater lake on the Yucatan Peninsula that hosts large microbialites. High sulfate concentrations distinguish Laguna Bacalar from other freshwater microbialite sites such as Pavilion Lake and Alchichica, Mexico, as well as from other aqueous features on the Yucatan Peninsula. While cyanobacterial populations have been described here previously, this study offers a more complete characterization of the microbial populations and corresponding biogeochemical cycling using a three-pronged geobiological approach of microscopy, high-throughput DNA sequencing, and lipid biomarker analyses. We identify and compare diverse microbial communities of Alphaproteobacteria, Deltaproteobacteria, and Gammaproteobacteria that vary with location along a bank-to-bank transect across the lake, within microbialites, and within a neighboring mangrove root agglomeration. In particular, sulfate-reducing bacteria are extremely common and diverse, constituting 7%-19% of phylogenetic diversity within the microbialites, and are hypothesized to significantly influence carbonate precipitation. In contrast, Cyanobacteria account for less than 1% of phylogenetic diversity. The distribution of lipid biomarkers reflects these changes in microbial ecology, providing meaningful biosignatures for the microbes in this system. Polysaturated short-chain fatty acids characteristic of cyanobacteria account for Bacalar microbialites. By contrast, even short-chain and monounsaturated short-chain fatty acids attributable to both Cyanobacteria and many other organisms including types of Alphaproteobacteria and Gammaproteobacteria constitute 43%-69% and 17%-25%, respectively, of total abundance in microbialites. While cyanobacteria are the largest and most visible microbes within these microbialites and dominate the mangrove root agglomeration, it is clear that their smaller, metabolically diverse associates are responsible for significant biogeochemical cycling in this 4. Don Quijote: de la prosa cervantina al teatro contemporáneo Directory of Open Access Journals (Sweden) Orazi, Veronica 2016-12-01 Full Text Available Study of six of the most recent and outstanding dramatisations (1999-2015 of Cervantes’s Don Quijote, such as Aventuras de Don Quijote, DQ. Don Quijote en Barcelona, El caballero de la triste figura, En un lugar de Manhattan, Elogio de la locura and En un lugar del Quijote. The analysis covers the main features of such adaptations: metanarration, metadrama, doubling of the narrative structure using other artistic languages (music, plastic arts, dance, etc., new technologies, genre hybridisation, transmediality, etc. The original text message, actualised and re-expressed by these modernisations, stands out as an atemporal one: the plays examined demonstrate its effectiveness in contemporary society and, according to the perspective of social theater, stimulate the reflection on them. 5. Evaluation of genetic toxicity of 6-diazo-5-oxo-l-norleucine (DON). Science.gov (United States) Kulkarni, Rohan M; Dakoulas, Emily W; Miller, Ken E; Terse, Pramod S 2017-09-01 DON (6-diazo-5-oxo-l-norleucine), a glutamine antagonist, was demonstrated to exhibit analgesic, antibacterial, antiviral and anticancer properties. The study was performed to characterize its in vitro and in vivo genetic toxicity potential. DON was tested in the bacterial reverse mutation assay (Ames test) using Salmonella typhimurium tester strains (TA98, TA100, TA1535 and TA1537) and Escherichia coli tester strain (WP2 uvrA) with and without S9 and also with reductive S9. In addition, DON was tested for the chromosome aberrations in Chinese hamster ovary (CHO) cells with or without S9 to evaluate the clastogenic potential. Furthermore, DON was also evaluated for its in vivo clastogenic activity by detecting micronuclei in polychromatic erythrocyte (PCE) cells in bone marrow collected from the male mice dosed intravenously with 500, 100, 10, 1 and 0.1 mg/kg at 24 and 48-h post-dose. The Ames mutagenicity assay showed no positive mutagenic responses. However, the in vitro chromosome aberration assay demonstrated dose dependent statistically positive increase in structural aberrations at 4 and 20-h exposure without S9 and also at 4-h exposure with S9. The in vivo micronucleus assay also revealed a statistically positive response for micronucleus formation at 500, 100 and 10 mg/kg at 24 and 48-h post-dose. Thus, DON appears to be negative in the Ames test but positive in the in vitro chromosome aberration assay and in the in vivo micronucleus assay. In conclusion, the results indicate DON is a genotoxic compound with a plausible epigenetic mechanism. 6. Modelización de la hidroquímica y sedimentoquímica de una laguna tipo playa (Cl- So2-4 Mg2+ - Na+: La Laguna Grande de Quero (Toledo Directory of Open Access Journals (Sweden) García del Cura, M. A. 1991-08-01 Full Text Available The «Laguna Grande de Quero», is a saline pond located on the aluvial system from the Cigüela and Riansares rivers. The pond's underground impermeable materials are claystone with gypsum from the Triassic ages. On the next reliefs appears gypsiferous-detrital and calcareous materials from the Tertiary ages. A model have been created for the evaporative process, correcting the saline effect bearing in mind the climatic parameters; the conclusions obtained are coherents with the experimental data, which have been obtained in two experimental pools placed for the evaporative- concentration processes chasing. The experimental precipitation sequence obtained was: calcite + gypsum â bloedite + thenardite â bloedite â epsomite + halite. This sequence has been studied about saits generated on the air-brine interface. Moreover coincide with the foreseeable theoric sequence, according to Valyashko diagrams. In the natural environment appears facies and paragenesis associations coherents with the experimental data. During the evaporative process to specific gravity and concentration evolution graphics show a stagnancy period, «plateau effect», that it seams to coincide with a differential heating from the depth waters. The explanation of this effect can be related with the salts dissolution previously formed.La Laguna Grande de Quero, se ubica en el sistema aluvial de los ríos Cigüela-Riansares. Los materiales del subsuelo impermeable de la laguna son lutitas con yeso del Trías. En los relieves próximos afloran materiales detrítico-yesíferos y calcáreos de edad Terciaria. Se ha establecido un modelo del proceso de evaporación, corrigiendo el efecto salino, y teniendo en cuenta los parámetros climáticos, obteniendo resultados coherentes con los datos obtenidos en las balsas experimentales instaladas para el seguimiento del proceso de evaporación-concentración de la salmuera. La secuencia de precipitación experimental 7. Laguna Verde after the extended power increase International Nuclear Information System (INIS) Herrera C, M. N.; Castaneda G, M. A.; Cardenas J, J. B.; Garcia de la C, F. M. 2012-10-01 The project of extended power increase that was implemented in both units of the nuclear power plant of Laguna Verde beginning with the stage feasibility evaluation in nuclear side of the facilities, that is to say the affectation of the power increase in the equipment s, systems and components of the nuclear power plant; besides the feasibility evaluation a study cost-benefit for the rehabilitated and modernization of the equipment s, systems and components of Plant Balance was realized. Once considered technical and economically feasible the project began the engineering evaluations required to carry out the licensing of the new operation conditions, as well as beginning to the elaboration of the technical specifications purchase of the equipment s, systems and components of the Plant Balance. While on one hand was carried out the administration of the licensing of the extended power increase for other was carried out the necessary engineering to make the physical changes in the conventional side of the nuclear power plant. Once concluded the constructive stage beginning the final stage of the project, the starting-up tests, operation and performance of the Units under the new operation conditions. This work describes this last stage that contains the technical base, the realized tests and the obtained results. (Author) 8. Hyperbaric Oxygen Therapy: Don't Be Misled Science.gov (United States) ... on Minorities Don't Be Fooled By Health Fraud Scams Beware of Illegally Marketed Diabetes Treatments Products ... feeds Follow FDA on Twitter Follow FDA on Facebook View FDA videos on YouTube View FDA photos ... 9. Estimation of fast neutron fluence in steel specimens type Laguna Verde in TRIGA Mark III reactor International Nuclear Information System (INIS) Galicia A, J.; Francois L, J. L.; Aguilar H, F. 2015-09-01 The main purpose of this work is to obtain the fluence of fast neutrons recorded within four specimens of carbon steel, similar to the material having the vessels of the BWR reactors of the nuclear power plant of Laguna Verde when subjected to neutron flux in a experimental facility of the TRIGA Mark III reactor, calculating an irradiation time to age the material so accelerated. For the calculation of the neutron flux in the specimens was used the Monte Carlo code MCNP5. In an initial stage, three sheets of natural molybdenum and molybdenum trioxide (MoO 3 ) were incorporated into a model developed of the TRIGA reactor operating at 1 M Wth, to calculate the resulting activity by setting a certain time of irradiation. The results obtained were compared with experimentally measured activities in these same materials to validate the calculated neutron flux in the model used. Subsequently, the fast neutron flux received by the steel specimens to incorporate them in the experimental facility E-16 of the reactor core model operating at nominal maximum power in steady-state was calculated, already from these calculations the irradiation time required was obtained for values of the neutron flux in the range of 10 18 n/cm 2 , which is estimated for the case of Laguna Verde after 32 years of effective operation at maximum power. (Author) 10. Don Germán OpenAIRE Juan Luis Mejía 1991-01-01 El veranillo de San Juan hace soportable el mediodía. Los "chorros d'oro" inundan de amarillo los antejardines del Prado. Las golondrinas veraneras invaden, al atardecer, los alrededores de la Biblioteca Departamental. Los voceadores de la suerte del paseo Bolívar claman a los cuatro vientos el número que cambiará su destino . Pero algo falta definitivamente en esta Barranquilla. De alguna manera la ciudad ya no es la misma. Falta Don Germán. 11. Radiological protection in Laguna Verde, the challenge of being better International Nuclear Information System (INIS) Serrano R, H. 2008-01-01 The operation of the nuclear power plants in the last decade is based on the application of standard directed towards the excellence. The nuclear power plant of Laguna Verde (CNLV), is not the exception and in the 18 years of commercial operation, the safety culture has matured in the personnel. Standard and political implemented like in the control of dosimeter alarms, equipment condition, meetings pre-work, the practice of protection to the systems and the fuel, as well as the order and the cleaning have distinguished to the CNLV with other power stations. The sense of property of the personnel towards its work is fundamental for the achievement of results. It is reason for the present work to show since it has been gotten to obtain results directed to the excellence in the activities or of normal operation and recharge, where the security is the principle priority. (Author) 12. Geología ambiental de la laguna de las Perdices, Monte, Buenos Aires, Argentina OpenAIRE Nauris Dangavs 2010-01-01 El estudio de la laguna de las Perdices abarca tres aspectos: el geolimnológico, el geoambiental y el de remediación. El primero ha consistido en caracterizar el medio físico de un ambiente léntico típico de la Pampasia meridional prácticamente desconocido. El segundo, la evaluación del grado de deterioro natural y la contaminación físico-química y bacteriológica. El tercero propicia las medidas para su recuperación, máxime teniendo en cuenta que el Municipio de Monte pretende transformarla e... 13. Analysis of internal events for the Unit 1 of the Laguna Verde nuclear power station; Analisis de eventos internos para la Unidad 1 de la Central Nucleolelectrica de Laguna Verde Energy Technology Data Exchange (ETDEWEB) Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R. [Comision Nacional de Seguridad Nuclear y Salvaguardias, 03000 Mexico D.F. (Mexico) 1993-07-01 This volume presents the results of the starter event analysis and the event tree analysis for the Unit 1 of the Laguna Verde nuclear power station. The starter event analysis includes the identification of all those internal events which cause a disturbance to the normal operation of the power station and require mitigation. Those called external events stay beyond the reach of this study. For the analysis of the Laguna Verde power station eight transient categories were identified, three categories of loss of coolant accidents (LOCA) inside the container, a LOCA out of the primary container, as well as the vessel break. The event trees analysis involves the development of the possible accident sequences for each category of starter events. Events trees by systems for the different types of LOCA and for all the transients were constructed. It was constructed the event tree for the total loss of alternating current, which represents an extension of the event tree for the loss of external power transient. Also the event tree by systems for the anticipated transients without scram was developed (ATWS). The events trees for the accident sequences includes the sequences evaluation with vulnerable nucleus, that is to say those sequences in which it is had an adequate cooling of nucleus but the remoting systems of residual heat had failed. In order to model adequately the previous, headings were added to the event tree for developing the sequences until the point where be solved the nucleus state. This process includes: the determination of the failure pressure of the primary container, the evaluation of the environment generated in the reactor building as result of the container failure or cracked of itself, the determination of the localization of the components in the reactor building and the construction of boolean expressions to estimate the failure of the subordinated components to an severe environment. (Author) 14. Application of six sigma to reloads design of the Laguna Verde Central with length until 17 days; Aplicacion de seis sigma para disenar recargas de la Central Laguna Verde con duracion hasta de 17 dias Energy Technology Data Exchange (ETDEWEB) Espinosa G, J.M. [Comision Federal de Electricidad, Central Laguna Verde, Subgerencia General de Operacion, Planeacion, Veracruz (Mexico)]. e-mail: [email protected] 2007-07-01 The more important value in the Laguna Verde Central it is the safety. The international experience it confirms us that the more safe plants its are those more productive, this conclusion and reasoning indicate to the power station that we are in the correct road, improving the acting we will obtain that greater interest for us in the Laguna Verde Central (to increase the safety) and as added value to be able to be one of the best business for the Federal Commission of Electricity. With a future vision and commitment of high acting was integrated in an external place to all the area headquarters: (Maintenance, Planning, Operation, Parts of Reserve, Finances, Contracts, Supplies, Warehouse, design Engineering, place Engineering, engineering of systems, radiological Protection, etc.) to carry out a combined work with the unique challenge of drifting with the biggest level detail the program of a recharge and certainly to get ready to achieve their execution (all this without omitting any consideration for smaller or simpler than it seemed), looking for high quality in the works, with and bigger level of safety, with the minimum possible dose, the more reasonable cost and considering a new concept of human character, to achieve the above-mentioned without the participant personnel's stress, with the premise that a good plan and commitment of all the only one that it can bring us as result it is the success of the whole organization. (Author) 15. The myth of the warrior: martial masculinity and the end of Don't Ask, Don't Tell. Science.gov (United States) Allsep, L Michael 2013-01-01 The image of the male warrior still dominates military culture, to the exclusion of women and homosexuals. Complicating the picture is a technological revolution that promises to widen the current gap between the myth and reality of the modern warrior even further. Nonetheless, despite long arguing that homosexuals were a direct threat to military culture and effectiveness, the Pentagon has largely treated the end of Don't Ask, Don't Tell as a policy matter. The difficulties still experienced by women in the armed services 40 years after they were first incorporated in significant numbers indicates that this response will be insufficient to address the deeper cultural issues. Gender issues implicate deeply held beliefs and values that persist even in the face of years of official admonishment and denial. Unless the military begins to transparently bridge the gap between the myth and reality of the modern warrior, military service without discrimination based on sexual orientation will remain an unachieved goal. 16. Quality assurance evolution at Laguna Verde Nuclear Power Plant Unit 1 and 2, regulatory aspects International Nuclear Information System (INIS) Leon Martinez, Cenobia 1996-01-01 Quality Assurance (QA) in Mexico started with the construction of the Laguna Verde Nuclear Power Plant. The Nuclear Regulatory Body, based in the adopted regulation, required the use of Quality Assurance in the design, construction and operation of the Plant. This paper describes the evolution of QA from its beginnings, through its developing phase up to this time, and shows the role of the Regulatory Body, which has participated actively in the implantation of QA in a properly manner, enforcing the utility in avoiding deviations and non-compliancies with the established regulation. (author) 17. Metodología para la selección del régimen de flujo en lagunas de estabilización Directory of Open Access Journals (Sweden) Luis Eduardo Cruz T. 2000-07-01 Full Text Available Para modelar procesos biológicos, se necesita información sobre la estequiometría y cinética de las reacciones y sobre el régimen hidráulico del sistema. La estequiometría de una reacción se refiere a la cantidad de reactantes consumidos (tales como sustratos, y a la cantidad de productos formados (tales como microorganismos. El régimen hidráulico hace referencia a la configuración del flujo dentro y fuera del proceso y a la mezcla y distribución de los sólidos del fluido dentro del reactor. El presente artículo se centrará en estudiar los diferentes regímenes de mezcla y sus modelos cinéticos de degradación de materia orgánica aplicados al caso específico de la laguna de estabilización de aguas residuales del municipio de Tocancipá. Además se discute la metodología para determinar el tipo de flujo que sepresenta en una laguna de estabilización. 18. Secondary forest succession and tree planting at the Laguna Cartagena and Cabo Rojo wildlife refuges in southwestern Puerto Rico Science.gov (United States) P.L. Weaver; J.J. Schwagerl 2008-01-01 Secondary forest succession and tree planting are contributing to the recovery of the Cabo Rojo refuge (Headquarters and Salinas tracts) and Laguna Cartagena refuge (Lagoon and Tinaja tracts) of the Fish and Wildlife Service in southwestern Puerto Rico. About 80 species, mainly natives, have been planted on 44 ha during the past 25 y in an effort to reduce the threat... 19. Análisis prospectivo del conflicto político ambiental, sobre el uso del espacio público Parque La Laguna, localizado en la Urbanización Nueva Casarapa, Estado Miranda.Venezuela Directory of Open Access Journals (Sweden) Mildred Zerpa 2013-06-01 Full Text Available Nueva Casarapa, es un complejo urbanístico integral concebido bajo el concepto de ciudad. Posee espacios abiertos, centros comerciales, espacios verdes y públicos cuidados por los propios habitantes y un parque central conocido como La Laguna. En 2009 comenzó una polémica que podría convertirse en conflicto socio natural con implicaciones en la gestión integral de riesgo del Municipio Plaza, por la incertidumbre acerca de cuál grupo es el más indicado para administrar y gestionar el parque La Laguna. 20. Science and Fiction. On Don Quijote’s Epistemological Skepticism Directory of Open Access Journals (Sweden) Félix Schmelzer 2016-11-01 Full Text Available The present work seeks to analyze the representation of scientific knowledge in Cervantes’ Quixote, focusing on various passages that underline the scientific expertise of don Quixote himself. It is shown that the novel contains a subtle critique of science, based on an epistemological skepticism with regard to the arbitrariness of our world concepts. The characterization of don Quixote as a man of science even permits deducting that he suffers from a ‘double mental damage’, caused by the lecture of both books of cavalry and science. Cervantes thus would consider science to be fiction, a very modern point of view. 1. de "subirnos al tiempo". La economía del "don" Directory of Open Access Journals (Sweden) Raúl García Durán 2007-01-01 Full Text Available Este trabajo resume las ideas contenidas en el libro -aún inédito- De la miseria de la economía a la plenitud de la fraternidad; o la economía del "don" como alternativa al capitalismo y la economía de mercado. En él se plantean alternativas radicales al capitalismo; particularmente, se ubica al "don" como camino de pensamiento y acción. Se documentan las proposiciones teóricas y aportes de la economía política, la antropología, la historia, para construir la manera en que el don podría contribuir a una reorganización social basada en nuevos-viejos principios. Se interrogan diversas experiencias histórico-antropológicas y su prefiguración actual en un nuevo modelo ético-político-ecológico que abarca las dimensiones local y global. 2. Le Don De Corps En Cote D\\'ivoire | Broalet | African Journal of ... African Journals Online (AJOL) Introduction Le don de corps qui permet de se procurer le matériel anatomique de dissection que constitue le cadavre humain n\\'existe pas en Afrique noire et notamment en Cote d\\' Ivoire. Objectif Recueillir des informations sur le don de corps à Abidjan. Méthode Les auteurs rapportent les informations recueillies au cours ... 3. Groundwater flow in a closed basin with a saline shallow lake in a volcanic area: Laguna Tuyajto, northern Chilean Altiplano of the Andes Energy Technology Data Exchange (ETDEWEB) Herrera, Christian, E-mail: [email protected] [Departamento de Ciencias Geológicas, Universidad Católica del Norte, Casilla 1280, Antofagasta (Chile); Centro de Investigación Tecnológica del Agua en el Desierto (CEITSAZA), Universidad Católica del Norte, Casilla 1280, Antofagasta (Chile); Custodio, Emilio [Department of Geo-Engineering, Technical University of Catalonia/Barcelona Tech (UPC), Barcelona (Spain); Chong, Guillermo [Departamento de Ciencias Geológicas, Universidad Católica del Norte, Casilla 1280, Antofagasta (Chile); Lambán, Luis Javier [Geological Institute of Spain (IGME), Zaragoza (Spain); Riquelme, Rodrigo; Wilke, Hans [Departamento de Ciencias Geológicas, Universidad Católica del Norte, Casilla 1280, Antofagasta (Chile); Jódar, Jorge [Department of Geo-Engineering, Technical University of Catalonia/Barcelona Tech (UPC), Barcelona (Spain); Urrutia, Javier; Urqueta, Harry [Departamento de Ciencias Geológicas, Universidad Católica del Norte, Casilla 1280, Antofagasta (Chile); Centro de Investigación Tecnológica del Agua en el Desierto (CEITSAZA), Universidad Católica del Norte, Casilla 1280, Antofagasta (Chile); Sarmiento, Alvaro [Departamento de Ciencias Geológicas, Universidad Católica del Norte, Casilla 1280, Antofagasta (Chile); and others 2016-01-15 Laguna Tuyajto is a small, shallow saline water lake in the Andean Altiplano of northern Chile. In the eastern side it is fed by springs that discharge groundwater of the nearby volcanic aquifers. The area is arid: rainfall does not exceed 200 mm/year in the rainiest parts. The stable isotopic content of spring water shows that the recharge is originated mainly from winter rain, snow melt, and to a lesser extent from some short and intense sporadic rainfall events. Most of the spring water outflowing in the northern side of Laguna Tuyajto is recharged in the Tuyajto volcano. Most of the spring water in the eastern side and groundwater are recharged at higher elevations, in the rims of the nearby endorheic basins of Pampa Colorada and Pampa Las Tecas to the East. The presence of tritium in some deep wells in Pampa Colorada and Pampa Las Tecas indicates recent recharge. Gas emission in recent volcanoes increase the sulfate content of atmospheric deposition and this is reflected in local groundwater. The chemical composition and concentration of spring waters are the result of meteoric water evapo-concentration, water–rock interaction, and mainly the dissolution of old and buried evaporitic deposits. Groundwater flow is mostly shallow due to a low permeability ignimbrite layer of regional extent, which also hinders brine spreading below and around the lake. High deep temperatures near the recent Tuyajto volcano explain the high dissolved silica contents and the δ{sup 18}O shift to heavier values found in some of the spring waters. Laguna Tuyajto is a terminal lake where salts cumulate, mostly halite, but some brine transfer to the Salar de Aguas Calientes-3 cannot be excluded. The hydrogeological behavior of Laguna Tuyajto constitutes a model to understand the functioning of many other similar basins in other areas in the Andean Altiplano. - Highlights: • Recent volcanism formations play a key role in producing recharge. • Groundwater can flow across local 4. Groundwater flow in a closed basin with a saline shallow lake in a volcanic area: Laguna Tuyajto, northern Chilean Altiplano of the Andes International Nuclear Information System (INIS) Herrera, Christian; Custodio, Emilio; Chong, Guillermo; Lambán, Luis Javier; Riquelme, Rodrigo; Wilke, Hans; Jódar, Jorge; Urrutia, Javier; Urqueta, Harry; Sarmiento, Alvaro 2016-01-01 Laguna Tuyajto is a small, shallow saline water lake in the Andean Altiplano of northern Chile. In the eastern side it is fed by springs that discharge groundwater of the nearby volcanic aquifers. The area is arid: rainfall does not exceed 200 mm/year in the rainiest parts. The stable isotopic content of spring water shows that the recharge is originated mainly from winter rain, snow melt, and to a lesser extent from some short and intense sporadic rainfall events. Most of the spring water outflowing in the northern side of Laguna Tuyajto is recharged in the Tuyajto volcano. Most of the spring water in the eastern side and groundwater are recharged at higher elevations, in the rims of the nearby endorheic basins of Pampa Colorada and Pampa Las Tecas to the East. The presence of tritium in some deep wells in Pampa Colorada and Pampa Las Tecas indicates recent recharge. Gas emission in recent volcanoes increase the sulfate content of atmospheric deposition and this is reflected in local groundwater. The chemical composition and concentration of spring waters are the result of meteoric water evapo-concentration, water–rock interaction, and mainly the dissolution of old and buried evaporitic deposits. Groundwater flow is mostly shallow due to a low permeability ignimbrite layer of regional extent, which also hinders brine spreading below and around the lake. High deep temperatures near the recent Tuyajto volcano explain the high dissolved silica contents and the δ"1"8O shift to heavier values found in some of the spring waters. Laguna Tuyajto is a terminal lake where salts cumulate, mostly halite, but some brine transfer to the Salar de Aguas Calientes-3 cannot be excluded. The hydrogeological behavior of Laguna Tuyajto constitutes a model to understand the functioning of many other similar basins in other areas in the Andean Altiplano. - Highlights: • Recent volcanism formations play a key role in producing recharge. • Groundwater can flow across local 5. Don Germán Directory of Open Access Journals (Sweden) Juan Luis Mejía 1991-01-01 Full Text Available El veranillo de San Juan hace soportable el mediodía. Los "chorros d'oro" inundan de amarillo los antejardines del Prado. Las golondrinas veraneras invaden, al atardecer, los alrededores de la Biblioteca Departamental. Los voceadores de la suerte del paseo Bolívar claman a los cuatro vientos el número que cambiará su destino . Pero algo falta definitivamente en esta Barranquilla. De alguna manera la ciudad ya no es la misma. Falta Don Germán. 6. Don Isidoro Laverde Amaya Directory of Open Access Journals (Sweden) Carlos López Narváez 1961-03-01 Full Text Available A la calidad sustantiva de los polígrafos, -estirpe de los Vergara, Eduardo Posada, Gustavo Arboleda, Otero Muñoz, Samper Ortega, Gómez Restrepo para nombrar solo algunos de los que "nos han precedido con la señal de la fe", como dice el sacro ritual, y en el servicio de las Letras patrias- pertenece con mérito eximio el prócer de la bibliografía colombiana, don Isidoro Laverde Amaya. 7. Sleep and sleep disorders in Don Quixote. Science.gov (United States) Iranzo, Alex; Santamaria, Joan; de Riquer, Martín 2004-01-01 In Don Quijote de la Mancha, Miguel de Cervantes presents Don Quixote as an amazing character of the 17th century who suffers from delusions and illusions, believing himself to be a medieval knight errant. Besides this neuropsychiatric condition, Cervantes included masterful descriptions of several sleep disorders such as insomnia, sleep deprivation, disruptive loud snoring and rapid eye movement sleep behaviour disorder. In addition, he described the occurrence of physiological, vivid dreams and habitual, post-prandial sleepiness--the siesta. Cervantes' concept of sleep as a passive state where all cerebral activities are almost absent is in conflict with his description of abnormal behaviours during sleep and vivid, fantastic dreams. His concept of sleep was shared by his contemporary, Shakespeare, and could have been influenced by the reading of the classical Spanish book of psychiatry Examen de Ingenios (1575). 8. Dr. S. Donald (Don) Stookey (1915-2014): Pioneering Researcher and Adventurer Science.gov (United States) Beall, George H. 2016-07-01 Don Stookey, the father of glass-ceramics, was a pioneer in inducing and understanding internal nucleation phenomena in glass. His early work on dense opal glasses and photosensitive precipitation of gold and silver in glass led to an amazing series of inventions: Fotalite, a photosensitive opal, chemically machined Fotoform and Fotoceram, and TiO2-nucleated Pyroceram products including missile nosecones and oven-proof cookware. He received a basic patent on glass-ceramics, which was contested and affirmed in court. Don was able to demonstrate a clear photochromic glass that showed reversible darkening for thousands of cycles. This material became a fixture in the ophthalmic industry. He went on to invent a full-color polychromatic glass, capable of yielding a permanent patterned and monolithic stained glass. In his life outside science, Don chaired an interfaith group that founded a home for the elderly in Corning. He was also a wilderness enthusiast, surviving a plane crash in the Arctic and two boat capsizings. Even in his later years, he continued fishing off the coast of Florida and on Lake Ontario and went solo on a trip to the Patagonian Andes. Don Stookey was a special person by any measure: an unassuming optimist, eminent scientist and inventor, adventurer, and a beloved family man. Introduction 9. To the Spanish Young People: Don Quixote Dreyfussard Directory of Open Access Journals (Sweden) Virginia Ramírez Martín 2013-12-01 Full Text Available In 1898, Spanish press take up part of its pages with a relevant international issue: the Dreyfus affair. The case was widely covered by Spanish newspapers, in special by Don Quijote, a Madrilenian satiric press, whose Director promoted a campaign in favour of Zola collecting signatures in order to the French litterateur was aware that Spain was close to him. This initiative is completed with a call to Spanish young people who is illustrated with a quixotic caricature. Cervantine character personifies the idea of justice getting to transmit during the Spanish crisis at the end of the nineteenth century the image of the nobleman forged by Spanish stereotypical, like a crusader fighting for a noble cause, thus turning Don Quixote into another dreyfussard. 10. Don't Panic! | NIH MedlinePlus the Magazine Science.gov (United States) ... of this page please turn Javascript on. Feature: Phobias and Anxiety Disorders Don't Panic! Past Issues / Fall 2010 Table of Contents Phobias and other anxiety disorders affect millions of Americans. ... 11. Turbine model for the Laguna Verde nucleo electric central based in the RELAP code International Nuclear Information System (INIS) Cortes M, F.S.; Ramos P, J.C.; Salazar S, E.; Chavez M, C. 2003-01-01 The Nuclear Power stations as Laguna Verde occupy at the present time a place every time but important as non pollutant alternative, economic and trusty to generate electricity. It is for it that the Group of Nuclear Engineering of the Engineering Faculty (GrlNFI) of the National Autonomous University of Mexico (UNAM) it develops investigation projects applied to Nuclear Centrals. One of the projects in process is the development of a Classroom simulator, which it can configures to consent to diverse models of nuclear systems with training purposes in normal operation, or, to consent to specialized nuclear codes for the analysis of transitory events and have a severe accident. This work describes the development, implementation and it proves of a simplified model of the Main turbine to be integrated to the group of models of the Classroom simulator. It is part of the current effort of GrlNFI guided to obtain a representation of all the dynamic models necessary to simulate the Plant Balance of the Laguna Verde Central. It is included the development of the unfolding graphic which represent the modeling of the Main turbine, and of the control interface that allows the user to manipulate in simple way, direct and interactive this device during the training or the analysis. With this work it is wanted to contribute to the training of new technicians and to support the operation personnel of the Centrals. Also, the developed infrastructure is guided to contribute in the design and analysis of new Nuclear Power stations with the contribution of new computational tools for the visualization, simulation and process control. (Author) 12. Dewey or Don't We? Science.gov (United States) Pendergrass, Devona J. 2013-01-01 "Dewey or don't we?" is the question that hundreds, if not thousands, of school librarians across the country are currently asking themselves. Do they throw out what is old but trusted for new organizational systems, or do they continue using the Dewey Decimal Classification (DDC) system and make changes and adjustments to the… 13. 15 years of production of electric energy of the Laguna Verde power plant, its plans and future International Nuclear Information System (INIS) Rivera C, A. 2005-01-01 In the year 2005 Laguna Verde power plant reaches 15 years of producing electric power in Mexico arriving to but of 100 million Megawatts-hour from their beginning of commercial activities. The Unit 1 that entered at July 29, 1990 and the Unit 2 at April 10, 1995, obtaining the Disposability Factors from their origin is: 84.63% in Unit 1 and 83.67% in Unit 2. The march of the X XI century gives big challenges of competition to the Laguna Verde Central, with the possible opening of the electric market to private investment, for their Goals and Objectives of a world class company, taking the evaluation system and qualification of the World Association of Nuclear Operators (WANO) that promotes the Excellence in the operation of the nuclear power stations in all their partners. This Association supports the development of programs that allow the monitoring of the behavior in Safety Culture, Human fulfilment, Equipment reliability, Industrial Safety, Planning, Programming and Control, Personalized Systematic Training, and the use of the Operational experience in the daily tasks. The present work tries to explain the system of evaluation/qualification of WANO, the definition of Goals and Objectives to reach the excellence and of the programs, it will present the Program of the Reliability of Equipment with its main actions the productivity. (Author) 14. Transient identification system with noising data and 'don't know' response International Nuclear Information System (INIS) Mol, Antonio C. de A.; Martinez, Aquilino S.; Schirru, Roberto 2002-01-01 In the last years, many different approaches based on neural network (NN) has been proposed for transient identification in nuclear power plants (NPP). Some of them focus the dynamic identification using recurrent neural networks however, they are not able to deal with unrecognized transients. Other kind of solution uses competitive learning in order to allow the 'don't know' response. In this case dynamic, dynamic features are not well represented. This work presents a new approach for neural network based transient identification which allows either dynamic identification and 'don't know'response. Such approach uses two multilayer neural networks trained with backpropagation algorithm. The first one is responsible for the dynamic identification. This NN uses, a short set (in a movable time window) of recent measurements of each variable avoiding the necessity of using starting events. The other one is used to validate the instantaneous identification (from the first net) through the validation of each variable. This net is responsible for allowing the system to provide 'don't know' response. In order to validate the method a NPP transient identification problem comprising 15 postulated accidents, simulated for a pressurized water reactor, was proposed in the validation process it has been considered noising data in other to evaluate the method robustness. Obtained results reveal the ability of the method in dealing with both dynamic identification of transients and correct 'don't know' response. In order to validate the method, a NPP transient identification problem comprising 15 postulated accidents simulated for a pressurized water reactor, was proposed in the validation process it has been considered noising data in order to evaluate the method robustness. Obtained results reveal the ability of the method in dealing with both dynamic identification of transients and correct 'don't know' response. (author) 15. DETERMINACIÓN DE LOS METALES PESADOS EN LA LAGUNA CHOQUENE, QUILCAPUNCO – PUTINA – PUNO OpenAIRE Machaca Hancco, Ernesto Samuel; Universidad Nacional del Altiplano 2013-01-01 El presente trabajo de investigación se ha efectuado en la mina Regina Palca 11, con el objetivo de determinar la concentración de los metales pesados y el grado de toxicidad en la Laguna Choquene Quilcapunco Putina. La metodología aplicada fue analítica experimental y descriptiva de las tareas de investigación propuesta en el presente trabajo en los tres puntos de muestreo. El comportamiento geoquímico de los metales pesados (de arsénico, cobre, plomo, plata), en los diques de colas y esc... 16. Why Don't All Professors Use Computers? Science.gov (United States) Drew, David Eli 1989-01-01 Discusses the adoption of computer technology at universities and examines reasons why some professors don't use computers. Topics discussed include computer applications, including artificial intelligence, social science research, statistical analysis, and cooperative research; appropriateness of the technology for the task; the Computer Aptitude… 17. Participation of the research institutes in the safety aspects of the Laguna Verde nuclear power plant International Nuclear Information System (INIS) Sanchez G, J. 1991-01-01 The main activities undertaken by two research institutes of Mexico, the Instituto de Investigaciones Electricas and the Instituto Nacional de Investigaciones Nucleares, related to the safety of the Laguna Verde Nuclear Power Plant, are described. Among these activities, the development of a system for data acquisition and analysis during pre-operational tests, the design and construction of a full-scope simulator, the in-core fuel management and the establishment of an equipment qualification laboratory, stand out. It is considered that there exists a large potential for further participation. (author) 18. Dr. S. Donald (Don Stookey: (1915-2014: Pioneering Researcher and Adventurer Directory of Open Access Journals (Sweden) George Halsey Beall 2016-08-01 Full Text Available Don Stookey was a special person by any measure: an unassuming optimist, eminent scientist and inventor, adventurer, and a beloved family man. Don Stookey, the father of glass-ceramics, was a pioneer in inducing and understanding internal nucleation phenomena in glass. His early work on dense opal glasses and photosensitive precipitation of gold and silver in glass led to an amazing series of inventions: Fotalite®, a photosensitive opal, chemically machined Fotoform® and Fotoceram®, and TiO2-nucleated Pyroceram™ products including missile nosecones and oven-proof cookware. He received a basic patent on glass-ceramics which was contested and affirmed in court.Don was able to demonstrate a clear photochromic glass that showed reversible darkening for thousands of cycles. This material became a fixture in the ophthalmic industry. He went on to invent a full-color polychromatic glass capable of yielding a permanent patterned and monolithic stained glass.In his life outside science, Don chaired an interfaith group that founded a home for the elderly in Corning. He was also a wilderness enthusiast, surviving a plane crash in the Arctic and two boat capsizings. Even In his later years, he continued fishing off the coast of Florida and on Lake Ontario, and went solo on a trip to the Patagonian Andes. 19. Efectos antrópicos sobre las praderas sumergidas de carófitos en una laguna cárstica Directory of Open Access Journals (Sweden) Sosnovsky, Alejandro 2005-06-01 Full Text Available Charophytes are submerged macrophyte algae often found in diverse aquatic habitats. Chara-dominated lakes are typically hard water, calcium-rich and low in phosphate. La Colgada is a 18 m deep, 103 ha small lake located in a tourist area, which has partly resulted in nutrient increases in recent years. Chara hispida var. major (Hartm. R.D. Wood and Chara hispida f. polyacantha (A. Braun R.D. Wood meadows are extensive in this ecosystem, but their distribution are influenced by human activities. Negligible densities of C. hispida, always covered by epiphytes, were recorded in the shores adjacent to tourist areas. Horizontal cover and biomass distributions were heterogeneous throughout the lake (0,95 ± 0,55 kg DW•m-2, with minimum values nearby the tourist area (0,68 ± 0,32 kg DW•m-2. Charophyte biomass was inversely related to depth in areas not influenced by anthropogenic impacts. However, that relationship did not occur in anthropized areas. The biomass range of Charophytes in La Colgada lake, 0,22-2,27 kg DW•m-2, was much higher than that recorded in other world lakes and wetlands.Los carófitos son algas macrófitas que viven sumergidas en aguas con características físico-químicas muy diferentes. La Colgada es una laguna de 103 ha y 18 m de profundidad máxima ubicada en una zona de gran afluencia turística (Parque Natural Las Lagunas de Ruidera, Albacete-Ciudad Real, en la que los nutrientes han ido aumentando durante las últimas décadas. Los fondos de esta laguna están cubiertos parcialmente por formaciones monoespecíficas de Chara hispida var. major (Hartm. R.D. Wood y Chara hispida f. polyacantha (A. Braun R.D. Wood, cuya distribución está siendo afectada por las actividades humanas. Las densidades más bajas de C. hispida, siempre cubierta por abundantes algas epífitas filamentosas, se registraron en los bordes próximos a la zona más urbanizada. La distribución horizontal y la biomasa seca de C 20. Reproduction of the flow-power map of the Laguna Verde power plant; Reproduccion del mapa flujo-potencia de la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Amador G, R; Gonzalez M, V M [Comision Nacional de Seguridad Nuclear y Salvaguardias, 03000 Mexico D.F. (Mexico) 1993-07-01 The National Commission of Nuclear Safety and Safeguards (CNSNS) requires to have calculation tools which allows it to make analysis independent of the behavior of the reactor core of Laguna Verde nuclear power plant (CNLV) with the purpose to support the evaluation and discharge activities of the fuel recharges licensing. The software package Fms (Fuel Management System) allows to carry out an analysis of the core of the BWR type reactors along the operation cycle to detect possible anomalies and/or helping in the fuel management. In this work it is reproduced the flow-power for the CNLV using the Presto code of the Fms software package. The comparison of results with the map used by the operators of CNLV shows good agreement between them. Another exercise carried out was the changes study that the axial and radial power outlines undergo as well as the thermohydraulic parameters (LHGR, APLHGR, CPR) when moving a control rod. The obtained results show that is had the experience to effect analysis of the reactor behavior using the Presto-Fms code therefore the study of the rest of the software package for the obtention of nuclear parameters used in this code is recommended. (Author) 1. Edad de las terrazas y diques travertínicos de las Lagunas de Ruidera y sus implicaciones paleoclimáticas Directory of Open Access Journals (Sweden) Martínez Frías, J. 1988-04-01 Full Text Available Two generations of carbonate sinter deposits of sedimentary origin occur along the shore line of the Ruidera lakes. Both of them were formed during interglaciar type climate conditions. Based on 234 U/238 U and 230 U/234 U activity relationships, two sets of ages were obtained: 10.000 years and 80.000-140.000; tbe former for the lower terraces and sinter dykes, the latter for the upper terraces.En los bordes de las Lagunas de Ruidera, existen dos generaciones fundamentales de depósitos travertínicos. La datación de estos depósitos, mediante relaciones de actividades del 234 U/238 U y 230 Th/234 U permite diferenciar un conjunto de terrazas bajas y diques de edad inferior a 10.000 años, y un conjunto de terrazas altas de edad entre 80.000 y 140.000 años, en las que se distinguen dos episodios principales. Estos periodos de crecimiento de los travertinos, se identifican con condiciones climáticas equivalentes a las de un interglaciar húmedo. Por último, se hace una estimación de la velocidad de encajamiento de las lagunas. 2. Buy, don't build -- What does that mean for a software developer? International Nuclear Information System (INIS) Little, T.; Rahi, M.A.; Sinclair, C. 1995-01-01 The buzz phrase of the 1990's for the petroleum software industry has become ''buy, don't build.'' For an end user in an oil company, this generally means acquiring application software rather than developing it internally. The concept of buy, don't build can also apply for a software developer. Purchasing software toolkit components can expedite the development of an application as well as reduce future support requirements 3. A High-Resolution Reconstruction of Late Holocene Environmental Change from Laguna Ek'Naab, Northern Holmul Region, Peten, Guatemala Science.gov (United States) Anderson, L.; Wahl, D.; Estrada-Belli, F. 2015-12-01 Widespread demographic shifts in the southern Maya lowlands at the end of the Classic period have been attributed to environmental change caused by human activity and/or climate variability. Fire was essential to landscape modification and was a primary agent of environmental change associated with prehispanic land use. While several studies have provided insight into the dynamic relationship between natural and anthropogenic drivers of change, defining the specific interplay between natural environmental change, human modification of the environment, and cultural response to changes remains a persistent challenge. Here we present the results of a multi-proxy study that reconstructs fire history, agricultural land use, and environmental change during and after Pre-Columbian Maya settlement. Results are interpreted in the context of settlement history as inferred from archaeological mapping around the study site. Our findings suggest landscape disturbance, as indicated by erosion, local burning, and nearby maize agriculture, was at its peak during the Early Classic period. This disturbance was likely due to large-scale settlement at the nearby site of Witzna'. All proxies indicate a slow decline in disturbance into the Late Classic period, beginning around 1300 cal yr BP. Cival and Chanchich, two proximal site centers to the south of Laguna Ek'Naab, supported their largest populations during the Late Preclassic and Late Classic, with little or no settlement during the Early Classic. The data from Laguna Ek'Naab suggests that Witzna' may have been an important center during the Early Classic. Whether the decreasing environmental degradation after 1240 cal yr BP is do to a decline in local population or changing land use strategies is not discernable based on the data thus far. However, the near complete absence of burning and continued decrease in erosion from 1240-1090 cal yr BP suggests little anthropogenic activity in the area. Burning resumes in the watershed 4. Efecto tóxico de DDT y endosulfan en postlarvas de camarón blanco, Litopenaeus vannamei (Decapoda:Penaeidaede Chiapas,México Directory of Open Access Journals (Sweden) Vicente Castro-Castro 2005-06-01 Full Text Available Con el fin de conocer la toxicidad del DDT y endosulfan sobre postlarvas de camarón blanco (Litopenaeus vannaei, se realizaron pruebas de toxicidad aguda en condiciones de laboratorio por 168 h, con temperatura de 29 ± 1 °C, salinidad de 3 ± 1 ‰ y pH en 8 ± 1.Se calculó la concentración letal media (LC50 , la LC50 "incipiente", los tiempos medios de muerte (LT50 , la Máxima Concentración Aceptable del Tóxico (MACT y el "Nivel de Seguridad" (LS; así mismo, en los organismos sobrevivientes se determinó la concentración a la que el crecimiento de los organismos se reduce en un 5 y 50% (CE5 y CE50 . Se evaluaron además las alteraciones en el consumo de oxígeno. El DDT fue 3 veces más tóxico que el endosulfan; sin embargo, los organismos resultaron ser muy sensibles a ambos compuestos. La tasa de crecimiento de las postlarvas disminuyó en un 80 y 50% para el DDT y endosulfan respectivamente. La baja resistencia de las postlarvas al DDT y endosulfan, y las concentraciones de estos compuestos en la laguna, sugieren que si se diera un ingreso adicional de estos plaguicidas al sistema, es muy probable un potencial impacto en la producción de camarón del sistemaToxic efect of DDT and endosulfan in white shrimp postlarvae Litopenaeus vannamei (Decapoda: Penaeidae from Chiapas, Mexico .We analized acute toxicity in white shrimp (Litopenaeus vannamei postlarvae exposed to two chlorinated pesticides, DDT and endosulfan, under laboratory conditions during 168 hours, with controlled temperature (29 ± 1°C, salinity (3 ± 1 ‰ and pH (8 ± 1. Median lethal concentrations (LC50 , "incipient" LC50, median lethal time (LT50 the "maximum acceptable concentration of the toxic compound" (MACT and "the safety level" (SL were determined. The concentration of the compounds at which organism growth was reduced by 5 and 50% (EC5 and EC50 , as well as changes in oxygen consumption patterns were determined in the surviving postlarvae.They were very 5. Improvements to the RELAP/SCDAPSIM of Laguna Verde model for the analysis of transients and accidents; Mejoras al modelo de Laguna Verde de RELAP/SCDAPSIM para el analisis de transitorios y accidentes Energy Technology Data Exchange (ETDEWEB) Amador G, R.; Castillo D, R.; Ortiz V, J.; Araiza M, E.; Martinez C, E., E-mail: [email protected] [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico) 2016-09-15 This work presents the improvements to the integral model of the nuclear power plant of Laguna Verde for the RELAP/SCDAPSIM code, for the simulation of transients and severe accidents. The model includes a new detailed geometry of the steam lines, as well as improvements in the performance of the emergency systems. A primary containment model has also been created, which will be used to analyze the effect of safety valve and relief valve discharges to the wet well suppression pool and the effect of the rupture of a recirculation loop on the dry well. The simulations performed with the new model show that the changes made improve the prediction of the phenomenology involved during transients and accidents. (Author) 6. Early alert system for oscillations detection applied to the Central of Laguna Verde International Nuclear Information System (INIS) Calleros M, G.; Zapata Y, M.; Avila N, A.; Herrera H, S. F. 2011-11-01 The code Early Alert System developed by Engineering of the Reactor of the nuclear power plant of Laguna Verde is presented, showing its reliability like preventive and corrective instrument to external interferences to the reactor core, due to equipment malfunction associated to the typical systems of a nuclear power plant, as those that control the reactor pressure, those that feed water to the reactor, those that control the valves of the main turbine. With this purpose, real cases of application of the System are shown where the results are compared with the independent evaluations carried out by the supplier, observing compatibility in both results. The benefits of the logarithm are discussed in the nuclear industry as soon as in non nuclear ambits. (Author) 7. Perspectives of the central Laguna Verde after Fukushima for the period 2012 at the 2015 in operation and maintenance; Perspectivas de la central Laguna Verde despues de Fukushima para el periodo 2012 al 2015 en operacion y mantenimiento Energy Technology Data Exchange (ETDEWEB) Rivera C, A., E-mail: [email protected] [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km 42.5, Veracruz (Mexico) 2012-10-15 The Nuclear Power Plants Management of the Federal Commission of Electricity in Mexico by means an internal analysis confronts the threat to the nuclear industry of the event of Fukushima that affected the public opinion, and the emission of new regulations. This situation demands to improve the results of the operation and maintenance of the nuclear power plant of Laguna Verde, to contribute value with their excellence in the acting to the nuclear option in Mexico. The internal analysis defined with clarity the perspectives based on weaknesses and strengths of the operation (monitoring and control of on-line parameters), and in the maintenance (sustained by the planning), enriched with the external experiences emitted by the institutes INPO and WANO for the nuclear industry, with all this strategic objectives 2012 to 2015 were presented and the initiatives as the extension of the useful life to 20 years more, as well as the focused actions to diminish the threat that the event of Fukushima influenced negatively in the public opinion, by means the diffusion of the good results that can be obtained in the nuclear power plant of Laguna Verde between 2012 and 2015, taking advantage of its modernized power of 810 MW-hour for each generating unit, doing visible that the Project of Extended Power Increase is a generation reality of 120% of the original value, to be able to enter at the excellence levels of the nuclear world. (Author) 8. 77 FR 37031 - Don W. Gilbert Hydro Power, LLC; Notice of Application Tendered for Filing With the Commission... Science.gov (United States) 2012-06-20 ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14367-001] Don W. Gilbert... No.: 14367-001. c. Date filed: May 30, 2012. d. Applicant: Don W. Gilbert Hydro Power, LLC. e. Name... Utility Regulatory Policies Act of 1978, 16 U.S.C. 2705, 2708.] h. Applicant Contact: Don W. Gilbert and... 9. Cervantes and the Lirical Poetry: Don Quixote Directory of Open Access Journals (Sweden) Fernando Romo Feito 2012-12-01 Full Text Available This essay examines the lyrical poems included in the first and the second part of Don Quixote. The different classes of poems are studied attending to its narrative context. But the poetry is also studied by relating it with metrical and aesthetical categories: Realism, Parody, Manierism… 10. Stress corrosion evaluation on stainless steel 304 pipes in Laguna Verde Nuclear Power Plant International Nuclear Information System (INIS) Arganis J, C.R. 1996-01-01 Inside the frame of the project IAEA/MEX-41044 'Stress corrosion as a starting event of accidents in nuclear plants', and of the institutional project IA-252 under the same name, it was required from the Laguna Verde Nuclear Plant, material equivalent to the one employed in the piping of the primary recycling system. Laguna Verde Nuclear Plant granted two tracks of tubes, that could be used to substitute the ones that are in operation, as is the tube SA-358TP304 CL-QC with transversal welding, designated as ER-316-LQA. According to the report entitles 'Revision of the operational experience related to corrosion in the nuclear plants' it was found that the stress corrosion is the principal mechanism of corrosion present in the nuclear plants. Previous records indicate that sensitized stainless steels are resistant to stress corrosion in testings of constant loading in sea water (3.5% of chlorides approximately) to 80 Centigrade and to 80% of the limit of conveyance and that a solution of 22% of NaCl to 90 Centigrade, produces cracking due to stress corrosion in highly sensitized steels, in tests of speed of slow extension (SSRT), to a speed of 1x10 -6 s -1 . Daniels reports that there is a direct relation between the speed limit of detection of the SSRT test and the concentration of chlorides, for stainless steels tested to 100 Centigrade. The minimum detection speed of susceptibility to stress corrosion for solution to 20% of NaCl, is of 1x10 -7 s -1 . Taking into account these considerations, the employment of a solution with 22% of NaCl to 90 Centigrade to a speed of 1x10 -6 s -1 seems a good choice for the evaluation of stainless steel. (Author) 11. Magnetic molecularly imprinted polymer for the selective extraction of hesperetin from the dried pericarp of Citrus reticulata Blanco. Science.gov (United States) Wang, Dan-Dan; Gao, Die; Xu, Wan-Jun; Li, Fan; Yin, Man-Ni; Fu, Qi-Feng; Xia, Zhi-Ning 2018-07-01 In present study, novel magnetic molecularly imprinted polymers for hesperetin were successfully prepared by surface molecular imprinting method using functionalized Fe 3 O 4 particles as the magnetic cores. Hesperetin as the template, N-Isopropylacrylamide as the functional monomer, ethylene glycol dimethyl acrylate as the crosslinker, 2,2-azobisisobutyonnitrile as initiator and acetonitrile-methanol (3:1, v/v) as the porogen were applied in the preparation process. Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscope, x-ray diffraction and vibrating sample magnetometry were applied to characterize the magnetic molecularly imprinted polymers. The adsorption experiments indicated that the magnetic molecularly imprinted polymers performed high selective recognition property to hesperetin. The selectivity experiment indicated that the adsorption capacity and selectivity of polymers to hesperetin was higher than that of luteolin, baicalein and ombuin. Furthermore, the magnetic molecularly imprinted polymers were employed as adsorbents for extraction and enrichment of hesperetin from the dried pericarp of Citrus reticulata Blanco. The recoveries of hesperetin in the dried pericarp of Citrus reticulata Blanco ranged from 90.5% to 96.9%. The linear range of 0.15-110.72 µg/mL was obtained with correlation coefficient of greater than 0.9991. The limit of detection and quantification of the proposed method was 0.06 µg/mL and 0.15 µg/mL, respectively. Based on three replicate measurements, intra-day RSD was 0.71% and inter-day RSD was 2.31%. These results demonstrated that the prepared magnetic molecularly imprinted polymers were proven to be an effective material for the selective adsorption and enrichment of hesperetin from natural medicines, fruits and et al. Copyright © 2018 Elsevier B.V. All rights reserved. 12. DESARROLLO TECNOLÓGICO PARA ELABORAR VINO BLANCO COMÚN EN MISIONES, CON EVALUACIÓN ECONÓMICA A ESCALA INDUSTRIAL Directory of Open Access Journals (Sweden) Miño Valdés , Juan Esteban 2013-01-01 Full Text Available El objetivo de este trabajo fue desarrollar una tecnología sustentable a escala industrial para elaborar vino blanco común, con uvas no viníferas cultivadas en Misiones. Este proyecto tecnológico se inició a escala laboratorio, continuó en planta piloto y proyectó a escala industrial. Se consideró como unidad productiva a 12 familias rurales con 27 ha de viñedo cada una. Las 8 etapas seguidas con metodología inductiva y deductiva fueron: La elaboración de vino blanco seco a escala laboratorio. La evaluación de las variables del proceso en las vinificaciones. El modelo matemático de la fermentación alcohólica en condiciones enológicas. La valoración de la aptitud de los vinos para el consumo humano. El establecimiento de un procedimiento tecnológico para la vinificación en planta piloto. La evaluación en planta piloto del procedimiento tecnológico establecido. El cálculo y la selección del equipamiento industrial. La estimación de los costos y la rentabilidad del proceso tecnológico industrial. Se alcanzó una tecnología para una capacidad de producción de 5.834 L (litros día-1, con indicadores económicos dinámicos cuyos valores fueron: valor actualizado neto de 6.602.666 UD, una taza interna de retorno del 60 % para un período de recuperación de inversión a valor actualizado neto de 3 años.
13. The National Institute of Nuclear Research (ININ) and its participation in the External Radiological Emergency Plans at Laguna Verde Power plant
International Nuclear Information System (INIS)
Suarez, G.
1998-01-01
In this article it is described the form in which the ININ participates in the External Radiological Emergency Plan at Laguna Verde Power plant. It is set the objective, mission and organization of this plan. The responsibilities and activities that plan has assigned are mentioned also the organization to fulfil them and the obtained results during 9 years of participation. (Author)
14. La cerámica Blanco sobre Rojo en el valle de Chancay y sus relaciones con el estilo Lima
Directory of Open Access Journals (Sweden)
2003-01-01
15. Application of six sigma to reloads design of the Laguna Verde Central with length until 17 days
International Nuclear Information System (INIS)
Espinosa G, J.M.
2007-01-01
The more important value in the Laguna Verde Central it is the safety. The international experience it confirms us that the more safe plants its are those more productive, this conclusion and reasoning indicate to the power station that we are in the correct road, improving the acting we will obtain that greater interest for us in the Laguna Verde Central (to increase the safety) and as added value to be able to be one of the best business for the Federal Commission of Electricity. With a future vision and commitment of high acting was integrated in an external place to all the area headquarters: (Maintenance, Planning, Operation, Parts of Reserve, Finances, Contracts, Supplies, Warehouse, design Engineering, place Engineering, engineering of systems, radiological Protection, etc.) to carry out a combined work with the unique challenge of drifting with the biggest level detail the program of a recharge and certainly to get ready to achieve their execution (all this without omitting any consideration for smaller or simpler than it seemed), looking for high quality in the works, with and bigger level of safety, with the minimum possible dose, the more reasonable cost and considering a new concept of human character, to achieve the above-mentioned without the participant personnel's stress, with the premise that a good plan and commitment of all the only one that it can bring us as result it is the success of the whole organization. (Author)
16. Distribution and community structure of ichthyoplankton in Laguna Madre seagrass meadows: Potential impact of seagrass species change
Science.gov (United States)
Tolan, J.M.; Holt, S.A.; Onuf, C.P.
1997-01-01
Seasonal ichthyoplankton surveys were made in the lower Laguna Madre, Texas, to compare the relative utilization of various nursery habitats (shoal grass, Halodule wrightii; manatee grass, Syringodium filiforme;, and unvegetated sand bottom) for both estuarine and offshore-spawned larvae. The species composition and abundance of fish larvae were determined for each habitat type at six locations in the bay. Pushnet ichthyoplankton sampling resulted in 296 total collections, yielding 107,463 fishes representing 55 species in 24 families. A broad spectrum of both the biotic and physical habitat parameters were examined to link the dispersion and distribution of both pre-settlement and post-settlement larvae to the utilization of shallow seagrass habitats. Sample sites were grouped by cluster analysis (Ward's minimum variance method) according to the similarity of their fish assemblages and subsequently examined with a multiple discriminant function analysis to identify important environmental variables. Abiotic environmental factors were most influential in defining groups for samples dominated by early larvae, whereas measures of seagrass complexity defined groups dominated by older larvae and juveniles. Juvenile-stage individuals showed clear habitat preference, with the more shallow Halodule wrightii being the habitat of choice, whereas early larvae of most species were widely distributed over all habitats. As a result of the recent shift of dominance from Halodule wrightii to Syringodium filiforme, overall reductions in the quality of nursery habitat for fishes in the lower Laguna Madre are projected.
17. Ang Social Network sa Facebook ng mga Taga-Batangas at ng mga Taga-Laguna: Isang Paghahambing
Directory of Open Access Journals (Sweden)
2013-12-01
Full Text Available Online social networking (OSN has become of great influence to Filipinos, where Facebook, Twitter, LinkedIn, Google+, and Instagram are among the popular ones. Their popularity, coupled with their intuitive and interactive use, allow one's personal information such as gender, age, address, relationship status, and list of friends to become publicly available. The accessibility of information from these sites allow, with the aid of computers, for the study of a wide population's characteristics even in a provincial scale. Aside from being neighbouring locales, the respective residents of Laguna and Batangas both derive their livelihoods from two lakes, Laguna de Bay and Taal Lake. Both residents experience similar problems, such as that, among many others, of fish kill. The goal of this research is to find out similarities in their respective online populations, particularly that of Facebook's. With the use of computational dynamic social network analysis (CDSNA, we found out that the two communities are similar, among others, as follows: both populations are dominated by single young female; Homophily was observed when choosing a friend in terms of age (i.e., friendships were created more often between people whose ages do not differ by at most five years; and Heterophily was observed when choosing friends in terms of gender (i.e., more friendships were created between a male and a female than between both people of the same gender. This paper also presents the differences in the structure of the two social networks, such as degrees of separation and preferential attachment.
18. The voice of Cervantes «creator» in Don Quixote
Directory of Open Access Journals (Sweden)
Florencio Sevilla Arroyo
2010-12-01
Full Text Available The aim of this paper is identifying the genuine voice of the Cervantes creator in the multiple choir of fictitious intermediaries involved in the authorship and the story of Don Quijote (reporter, editor, translator, Cide Hamete, supernarrator, readers, etc. trying, at the same time, to gauging the sense and the scope of their interventions. It happens that Miguel de Cervantes keeps to himself a novelistic role radically different depending on whether it is about the «story of story» or the «story itself»: refering to the first one, the author is out of the cast, delegating the reconstruction of Don Quixote’s legend in multiple fictional masks always comically manipulated; on the other hand, when it is the turn to the novelistic design of the chivalrous adventures of Don Quixote and Sancho, the voice of Cervantes creator comes to the forefront in order to take on, —as the «final author»— all narrative responsibility with absolute omniscience and solemnity. The resulting Quijote can only be explained from the intersection of both attitudes: the risible story of the most solemn/serious and magnificent novelistic bet never tried out..
19. Bioanalysis of 6-Diazo-5-oxo-L-norleucine (DON) in plasma and brain by ultra-performance liquid chromatography mass spectrometry
Science.gov (United States)
Alt, Jesse; Potter, Michelle C.; Rojas, Camilo; Slusher, Barbara S.
2015-01-01
Glutamine is an abundant amino acid that plays pivotal roles in cell growth, cell metabolism and neurotransmission. Dysregulation of glutamine-utilizing pathways has been associated with pathological conditions such as cancer and neurodegenerative diseases. 6-Diazo-5-Oxo-L-Norleucine (DON) is a reactive glutamine analog that inhibits enzymes affecting glutamine metabolism such as glutaminase, 2-N-amidotransferase, L-asparaginase and several enzymes involved in pyrimidine and purine de novo synthesis. As a result, DON is actively used in preclinical models of cancer and neurodegenerative disease. Moreover, there have been several clinical trials using DON to treat a variety of cancers. Considerations of dose and exposure are especially important with DON treatment due to its narrow therapeutic window and significant side effects. Consequently, a robust quantification bioassay is of interest. DON is a polar unstable molecule which has made quantification challenging. Here we report on the characterization of a bioanalytical method to quantify DON in tissue samples involving DON derivatization with 3N HCl in butanol. The derivatized product is lipophilic and stable. Detection of this analyte by mass spectrometry is fast, specific and can be used to quantify DON in plasma and brain tissue with a limit of detection in the low nanomolar level. PMID:25584882
20. Current situation of spent fuel management in the Laguna Verde Nuclear Power Plant, Veracruz, Mexico
International Nuclear Information System (INIS)
Moreno, C.V.
1994-01-01
The Comision Federal de Electricidad (CFE), owner and operator of the Laguna Verde nuclear power plant (2 x 654 MWe BWR), has twice decided to increase the storage capacity of the spent fuel pools of the reactors. The Comision Nacional de Seguridad Nuclear y Salvaguardias (CNSNS), the national nuclear regulatory authority, approved the increase by a factor of 2.66 in the storage capacity proposal by CFE in 1989. Each reactor spent fuel pool can now hold 614 t HM. The reracking was done at a cost of about US 13 per kg U, which will add only 0.042 mills per kWh to the fuel cycle cost. (author) 1. Total mercury of selected fish species from Laguna de Bay International Nuclear Information System (INIS) Relon, Milagros Lontoc 1996-01-01 Dalag Ophicephalus striatus Block, kanduli Arius thalassinus Ruppell, bia Amblygobius phalaena Cuvier et Valenciennes and tilapia Tilapia nilotica Linnnaeus collected from Laguna de Bay between Taguig and Binangonan area in August 1989 to July 1990 were analyzed for total mercury by atomic absorption spectrometry. The highest metal concentration in soft muscle tissue was observed in Dalag followed by kanduli, less in bia and least in tilapia with mean values of 0.021, 0.020, 0.013, and 0.008 ug/g, respectively. Analysis using two-way ANOVA showed a significant difference in the mean total mercury in ug/g in the difference fish samples, among the different months and the interaction between these two variables. Mean total mercury of the four fish samples were significantly higher in April than in October. The results show that the levels of total mercury in the fish samples are below the World Health Organization maximum tolerable consumption of mercury in food of 300 ug or 0.03 mg of total mercury per week. (author) 2. Calculating of radiation doses in rutinary unloads of liquid wastes from Laguna Verde nuclear power plant.; Calculo de las dosis de radiacion debidas a las descargas rutinarias de desechos liquidos de la central nucleoelectrica de Laguna Verde. Energy Technology Data Exchange (ETDEWEB) Molina, G 1986-12-31 Utilization of nuclear energy to generate electricity is increasingly being used to replace fossil fuels. During operation of nuclear power plants, radioactive materials are produced, a small fraction of which are released to environment as liquid or gaseous effluents. Estimation of radiation doses caused by effluents release has three purposes. During design phase of a nuclear station it is useful to adapt the wastes treatment systems to acceptable limits. During licensing phase, the regulator organism verifies the design of nuclear station effectuating estimation of doses. Finally, during operation, before every unload of radioactive effluents, radiation doses should be evaluated in order to fulfill technical specifications limiting the release of radioactive materials to environment. 1. To perform calculations of individual doses due to liquid radioactive effluents unload in units 1 and 2 of Laguna Verde nuclear power plant (In licensing phase). 2. To perform a parametric study of the effect of unload recirculation over individual dose, since recirculation has two principal effects: thermodynamical effects in nuclear station and radioactivity concentration; the last can affect the fullfilment of dose limits. 3. To perform the calculation of collective doses causes by unloads of liquid effluents within a radius of 80 km of the plant caused by unload of liquid radioactive effluents during normal operation and does not include doses during accident conditions. In Mexico the organism in charge of regulation of peaceful uses of nuclear energy is Comision Nacional de Seguridad Nuclear y Salvaguardias (CNSNS) and for Laguna Verde licensing, the regulations of the country who manufactured the reactor (USA). In Appendix C, units are explained. 3. Estimating of seismic return periods in Laguna Verde Nuclear Power Plant International Nuclear Information System (INIS) Flores R, J.H. 1993-01-01 The study of seismic risk in the site of Laguna Verde Nuclear Power Plant and surroundings was made considering the different periods of seismic return and the probability of occurrence in distinct time intervals (50, 75, 100, 125, 150 years) starting with the distribution of first type of extreme values of Gumbel (G1), the value used for the assessment of lifetime of lump was 50 years, and the rest of the periods are used to evaluate temporary nuclear cemeteries, it is to say for reducing the radioactivity of burned fuel assemblies. The seismic data belongs to the seismicity catalog (1920-1982) elaborated around the site, which average magnitude was 5 in the Richter Scale and are considered as shallow and are located in the Continental crust of North American shelf, and are induced by the pressure of the cocos shelf, being 36 % of the seismic movements of intermediate value and two seismic movements of deep value. (Author) 4. Mar Menor: una laguna singular y sensible. Evaluación científica de su estado OpenAIRE León, V.M. (Víctor Manuel); Bellido-Millán, J.M. (José María); Barcala-Bellod, E. (Elena); Vivas-Salvador, M. (Miguel); Franco-Navarro, I.J. (Ignacio José); García-Alcázar, A. (Alicia); Abellán-Martínez, E. (Emilia); Díaz-del-Río-Español, V. (Víctor); Moreno-González, R. (Rubén); Campillo-González, J.A. (Juan Antonio); Albentosa, M. (Marina) 2016-01-01 La información recogida en este libro se estructura en dos grandes bloques, uno de Biología y Ecología del Mar Menor (capítulos 1 al 8) y otro de Condiciones fisicoquímicas e impacto de actividades humanas en la laguna (capítulos 9 al 14). El primer bloque resume buena parte de los estudios ecológicos realizados en el Mar Menor, que han servido para mejorar su conocimiento y también para cambiar antiguas asunciones sobre la naturaleza y el funcionamiento de estos ecosistemas lagunares (C... 5. La sedimentación salina actual en las lagunas de La Mancha: una síntesis. OpenAIRE Peña Zarzuelo, Antonio de la; Marfil, R. 1986-01-01 [ES] La Mancha es una región natural de más de 30.000 Km2, caracterizada por una topografía extraordinariamente plana y un clima de tipo semiárido (Cuadro 1, Fig. 2), en la que existen numerosas lagunas salinas (Fig. 1), la mayoría de las cuales, por su régimen anual, pueden ser consideradas como «playa-lakes» (Fig. 3). Desde el punto de vista hidroquimico sus salmueras están integradas por: a) aniones: SO4 y Cl, con CO3 y CO 3H subordinados, y b) cationes: Mg 2+ y ... 6. Niebla ceruchis from Laguna Figueroa: dimorphic spore morphology and secondary compounds localized in pycnidia and apothecia Science.gov (United States) Enzien, M.; Margulis, L. 1988-01-01 During and after the floods of 1979-80 Niebla ceruchis growing epiphytically on Lycium brevipes was one of the dominant aspects of the vegetation in the coastal dunal complex bordering the microbial mats at Laguna Figueroa, Baja California Norte, Mexico. The lichen on denuded branches of Lycium was far more extensively distributed than Lycium lacking lichen. Unusual traits of this Niebla ceruchis strain, namely localization of lichen compounds in the mycobiont reproductive structures (pycnidia and apothecia) and simultaneous presence of bilocular and quadrilocular ascospores, are reported. The abundance of this coastal lichen cover at the microbial mat site has persisted through April 1988. 7. Mortandad de peces en la laguna de Yahuarcocha, cantón Ibarra, provincia de Imbabura. Febrero 2003 OpenAIRE Maridueña, Ana; Chalén, Norma; Coello, Dialhy; Cajas, Jacqueline; Elías, Esteban; Solís, Pilar; Aguilar, Fernando 2011-01-01 En febrero de 2003 en la Laguna de Yahuarcocha, se registró la muerte masiva de peces, estimándose que morían aproximadamente 500 peces/m2 por causas no conocidas. Fenómeno que se mantuvo durante algunas semanas disminuyendo paulatinamente el número de muertes. El Instituto Nacional de Pesca realizó un monitoreo durante los días 19 y 20 de marzo, con la finalidad de determinar las posibles causas, para lo cual se analizaron los parámetros ambientales, biológicos, identificación de las especie... 8. Don Quixote and Roque Guinart against the way of life of the influential people Directory of Open Access Journals (Sweden) Isabel M. Roger 2016-11-01 Full Text Available The apocryphal Second part of don Quixote altered many of the purposes of Cervantes. He changed the destination of his hero. As observed by don Quixote when visiting a printinghouse, its publication took place in Barcelona. The author gave prominence to a town as in picaresque novels. However, he did not modify his attitude towards the behaviour of the influential people, in keeping with Erasmus’ concept of stupidity. Surely, Cervantes reaffirmed his approach to the golden age through the presence of Roque Guinart, the only historical character who appears in the novel. This paper examines how the influential people behave in front of don Quixote, and how his performance is similar to that of Roque Guinart. 9. The Generation of 1898 and Cervantes : The invention of Don Quixote as a national symbol NARCIS (Netherlands) Storm, H.J.; Achiri, N.; Baraibar, A.; Schmelzer, F.K.E. 2015-01-01 Don Quixote became a Spanish national symbol thanks to the authors the Generation of 1898, such as Miguel de Unamuno, Azorín and Francisco Navarra Ledesma, who published their new interpretations during the 1905 commemoration of the publication of Cervantes', The Ingenious Gentleman Don Quixote of 10. A Novel Source of DOC and DON to Watershed Soils Science.gov (United States) Aitkenhead-Peterson, J. A. 2017-12-01 A source of dissolved organic carbon (DOC) and nitrogen (DON) to soils and groundwater is that emanating from decomposing mammals. Although there is an increase in human donor facilities (body farms) in the USA and in mass mortality events (MME) worldwide, this injection of DOC and DON into watershed soils has received little attention. Studies at two human donor facilities in Texas, USA have revealed that the purge fluid associated with decomposition is extremely high in DOC and DON and migrates down the soil profile. Two studies were carried out 1) The southeast Texas Applied Forensic Science (STAFS) facility on an Alfisol with a saturated hydraulic conductivity of 331 mm hr-1 and 83% sand and 2) the Forensic Anthropology Research Facility (FARF) on Mollisols with a saturated hydraulic conductivity of 3.6-9.7 mm hr-1 and 28-33% sand. The numbers of days since donors were laid in the environment ranged from 219-680 d at STAFS and 306-960 d at FACTS. Purge can occur between 5 and 30 d dependent on the time of year the body is placed and the resultant phenomenon is termed cadaver decomposition island (CDI). Soil cores were taken at 5 cm increments to a depth of 30 cm in the sandy soil and 15 cm in the clayey/rocky soil. In the sandy soils, DOC concentrations were significantly higher in all the CDI soils when compared to control soils at depths of 15, 20, 25 and 30 cm and ranged from 121.7 µg g-1 (30 cm) to 167.6 µg g-1 (15 cm) in control soils and 461.9 µg g-1 (30 cm) to 660.4 µg g-1 (15 cm) in CDI soils, representing a three- to four-fold increase in DOC relative to control soils. DON in all CDI soils was not significantly higher than control soils until 30 cm depth and ranged from 9.9-32.3 µg g-1 in CDI soils and 121.7 µg g-1 in control soil, representing a two- to seven-fold increase in DON relative to control soils. DOC concentrations in control soils at the FARF site at 15 cm ranged 215-365 µg g-1 while in the CDI soils DOC was higher (range: 270 11. The creator of the term 'anancasm' was Hungarian: Guyla Donáth (1849-1944). Science.gov (United States) Steinberg, Holger 2015-12-01 There is considerable confusion in the field of research on the history of psychiatry as to who created the term anancasm. This article seeks to clarify that the term was coined by the Hungarian psychiatrist Gyula Donáth, who was born in Baja, on the Danube, and worked mainly in Budapest. Donáth's publications reveal that his predominant sphere of interest and research was neurology and psychiatry. A number of his publications deal with epilepsy and obsessive-compulsive disorders. After a period of intensive research, during which he spent some time in Berlin at the clinic of neuroscientist Carl Westphal, Donáth proposed the term 'anancasm' in 1895 to describe compulsive mental processes. © The Author(s) 2015. 12. New recommendations of the ICRP and the ALARA program of the Nuclear power plant of Laguna Verde; Nuevas recomendaciones del ICRP y el programa ALARA de la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Padilla C, I [Comision Federal de Electricidad, Central Laguna Verde (Mexico) 1991-07-01 In view of the events happened in it finishes it decade, in the nuclear environment, it is necessary that any he/she practices that it involves exhibition to the radiation, real or potential, be detailed and systematically analyzed by the light of the current knowledge, capitalizing the generated experience. They think about three fundamental aspects in the campaign of radiological cultivation: 1. New methods of evaluation of equivalent dose. 2. Limit of individual dose, base of the change and control implications, and 3. Analysis philosophies and the application of the system of dose limitation. The program ALARA of the Laguna Verde Central from its installation in 1987 observes and it implements actions trending to optimize it practice of situation of potential and planned exhibition with the purpose of fulfilling the commitment settled down in the declaration of political of this program. 13. On the effects of the Fusarium toxin deoxynivalenol (DON) administered per os or intraperitoneal infusion to sows during days 63 to 70 of gestation. Science.gov (United States) Goyarts, Tanja; Brüssow, Klaus-Peter; Valenta, Hana; Tiemann, Ute; Jäger, Kathrin; Dänicke, Sven 2010-05-01 Six pregnant sows of 180.6 ± 5.6 kg were fed either a Fusarium-contaminated (4.42 mg DON and 48.3 µg ZON per kg, DON per os, n = 3) or a control diet (0.15 mg DON and 5 µg ZON/kg) in the period of days 63 and 70 of gestation. On day 63 of gestation, sows fed the control diet were implanted with an intraperitoneal osmotic minipump (delivery rate of 10 µL/h, for 7 days) containing 50 mg pure (98%) DON in 2 ml 50% DMSO (DON ip, n = 3). Frequent plasma samples were taken to estimate the kinetics after oral and ip DON exposure. The intended continuous delivery of DON by the intraperitoneal minipump could not be shown, as there was a plasma peak (Cmax) of 4.2-6.4 ng DON/mL either immediately (sow IP-2+3) or 2.5 h (sow IP-1) after implantation of the pump followed by a one-exponential decline with a mean half-time (t1/2) of 1.75-4.0 h and only negligible DON plasma concentrations after 12 h. Therefore, the DON ip exposure has to be regarded as one single dose 1 week before termination of experiment. The DON per os sows showed a mean basis level (after achieving a steady state) of DON plasma concentration of about 6-8 ng/mL, as also indicated by the plasma DON concentration at the termination of the experiment. On day 70, caesarean section was carried out, the fetuses were killed immediately after birth, and samples of plasma, urine, and bile were taken to analyze the concentration of DON and its metabolite de-epoxy-DON. At necropsy there were no macroscopic lesions observed in any organ of either sows or piglets. Histopathological evaluation of sows liver and spleen revealed no alterations. The proliferation rate of peripheral blood mononuclear cells (PBMC) with or without stimulation was not affected by the kind of DON treatment. The exposure of pregnant sows at mid-gestation (days 63-70, period of organogenesis) to a Fusarium toxin-contaminated diet (4.42 mg DON and 0.048 mg ZON per kg) or pure DON via intraperitoneal osmotic minipump 14. Analysis of internal events for the Unit 1 of the Laguna Verde nuclear power station International Nuclear Information System (INIS) Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R. 1993-01-01 This volume presents the results of the starter event analysis and the event tree analysis for the Unit 1 of the Laguna Verde nuclear power station. The starter event analysis includes the identification of all those internal events which cause a disturbance to the normal operation of the power station and require mitigation. Those called external events stay beyond the reach of this study. For the analysis of the Laguna Verde power station eight transient categories were identified, three categories of loss of coolant accidents (LOCA) inside the container, a LOCA out of the primary container, as well as the vessel break. The event trees analysis involves the development of the possible accident sequences for each category of starter events. Events trees by systems for the different types of LOCA and for all the transients were constructed. It was constructed the event tree for the total loss of alternating current, which represents an extension of the event tree for the loss of external power transient. Also the event tree by systems for the anticipated transients without scram was developed (ATWS). The events trees for the accident sequences includes the sequences evaluation with vulnerable nucleus, that is to say those sequences in which it is had an adequate cooling of nucleus but the remoting systems of residual heat had failed. In order to model adequately the previous, headings were added to the event tree for developing the sequences until the point where be solved the nucleus state. This process includes: the determination of the failure pressure of the primary container, the evaluation of the environment generated in the reactor building as result of the container failure or cracked of itself, the determination of the localization of the components in the reactor building and the construction of boolean expressions to estimate the failure of the subordinated components to an severe environment. (Author) 15. Thermal limits validation of gamma thermometer power adaption in CFE Laguna Verde 2 reactor core Energy Technology Data Exchange (ETDEWEB) Cuevas V, G.; Banfield, J. [GE-Hitachi Nuclear Energy Americas LLC, Global Nuclear Fuel, Americas LLC, 3901 Castle Hayne Road, Wilmingtonm, North Carolina (United States); Avila N, A., E-mail: [email protected] [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Carretera Cardel-Nautla Km 42.5, Alto Lucero, Veracruz (Mexico) 2016-09-15 This paper presents the status of GEH work on Gamma Thermometer (GT) validation using the signals of the instruments installed in the Laguna Verde Unit 2 reactor core. The long-standing technical collaboration between Comision Federal de Electricidad (CFE), Global Nuclear Fuel - Americas LLC (GNF) and GE-Hitachi Nuclear Energy Americas LLC (GEH) is moving forward with solid steps to a final implementation of GTs in a nuclear reactor core. Each GT is integrated into a slightly modified Local Power Range Monitor (LPRM) assembly. Six instrumentation strings are equipped with two gamma field detectors for a total of twenty-four bundles whose calculated powers are adapted to the instrumentation readings in addition to their use as calibration instruments for LPRMs. Since November 2007, the six GT instrumentation strings have been operable with almost no degradation by the strong neutron and gamma fluxes in the Laguna Verde Unit 2 reactor core. In this paper, the thermal limits, Critical Power Ratio (CPR) and maximum Linear Heat Generation Rate (LHGR), of bundles directly monitored by either Traverse In-core Probes (TIPs) or GTs are used to establish validation results that confirm the viability of TIP system replacement with automatic fixed in-core probes (AFIPs, GTs, in a Boiling Water Reactor. The new GNF steady-state reactor core simulator AETNA02 is used to obtain power and exposure distribution. Using this code with an updated methodology for GT power adaption, a reduced value of the GT interpolation uncertainty is obtained that is fed into the LHGR calculation. This new method achieves margin recovery for the adapted thermal limits for use in the Economic Simplified Boiling Water Reactor (ESBWR) or any other BWR in the future that employs a GT based AFIP system for local power measurements. (Author) 16. Thermal limits validation of gamma thermometer power adaption in CFE Laguna Verde 2 reactor core International Nuclear Information System (INIS) Cuevas V, G.; Banfield, J.; Avila N, A. 2016-09-01 This paper presents the status of GEH work on Gamma Thermometer (GT) validation using the signals of the instruments installed in the Laguna Verde Unit 2 reactor core. The long-standing technical collaboration between Comision Federal de Electricidad (CFE), Global Nuclear Fuel - Americas LLC (GNF) and GE-Hitachi Nuclear Energy Americas LLC (GEH) is moving forward with solid steps to a final implementation of GTs in a nuclear reactor core. Each GT is integrated into a slightly modified Local Power Range Monitor (LPRM) assembly. Six instrumentation strings are equipped with two gamma field detectors for a total of twenty-four bundles whose calculated powers are adapted to the instrumentation readings in addition to their use as calibration instruments for LPRMs. Since November 2007, the six GT instrumentation strings have been operable with almost no degradation by the strong neutron and gamma fluxes in the Laguna Verde Unit 2 reactor core. In this paper, the thermal limits, Critical Power Ratio (CPR) and maximum Linear Heat Generation Rate (LHGR), of bundles directly monitored by either Traverse In-core Probes (TIPs) or GTs are used to establish validation results that confirm the viability of TIP system replacement with automatic fixed in-core probes (AFIPs, GTs, in a Boiling Water Reactor. The new GNF steady-state reactor core simulator AETNA02 is used to obtain power and exposure distribution. Using this code with an updated methodology for GT power adaption, a reduced value of the GT interpolation uncertainty is obtained that is fed into the LHGR calculation. This new method achieves margin recovery for the adapted thermal limits for use in the Economic Simplified Boiling Water Reactor (ESBWR) or any other BWR in the future that employs a GT based AFIP system for local power measurements. (Author) 17. Mineral characterisation of Don Pao rare earth deposit in Vietnam International Nuclear Information System (INIS) XuanBen, T. 1998-01-01 Full text: The Don Pao Rare Earth Deposit was discovered in 1959 in Phon Tho district, about 450km North-West of Hanoi capital. Geological work was conducted between 1959-95, resulting in 60 ore bodies of various sizes being identified. The ore bodies are irregularly shaped nests, lenses and veins hosted in the shear zone, at the margin of a Paeleogene aged syenite massif. The mineral composition of Don Pao Deposit is very complex, consisting of more than 50 minerals. Among them, basnaesite, parisite, fluorite and barite are the main constituent minerals of the ore. All the minerals were identified by the modern methods of mineralogical studies. Based on the constituent mineral ratios, four ore types have been distinguished in the deposit: 1. Rare earth ore containing over 5 percent of RE 2 O 3 . 2. Rare Earth-Barite ore containing 0.5 to 30 percent of RE 2 O 3 . 3. Rare Earth-Barite-Fluorite ore containing 1 to 5 percent of RE 2 O 3 . 4. Rare Earth bearing Fluorite ore containing 1 to 5 percent of RE 2 O 3 . According to the benefication test, the ores in Don Pao can be enriched to a concentrate of 60 percent of RE 2 O 3 with a recover of 75 percent 18. Economic analysis of extended cycles in the Laguna Verde nuclear power plant; Analisis economico de ciclos de extendidos en la Central Nucleoelectrica Laguna Verde Energy Technology Data Exchange (ETDEWEB) Hernandez N, H.; Hernandez M, J.L.; Francois L, J.L. [Facultad de Ingenieria, UNAM, 04510 Mexico D.F. (Mexico)]. E-mail: [email protected] 2004-07-01 The present work presents a preliminary analysis of economic type of extended cycles of operation of the Unit One in the Laguna Verde nuclear power plant. It is analysed an equilibrium cycle of 18 months firstly, with base to the Plan of Use of Energy of the Federal Commission of Electricity, being evaluated the cost of the energy until the end of the useful life of the plant. Later on an alternative recharge scenario is presented with base to an equilibrium cycle of 24 months, implemented to the beginning of the cycle 11, without considering transition cycles. It is added in both cycles the cost of the substitution energy, considering the unitary cost of the fuel of a dual thermoelectric power station of 350 M We and evaluating in each operation cycle, in both scenarios, the value of the substitution energy. The results show that a reduction of the days of recharge in the cycle of 24 months could make this option but favorable economically. The duration of the period of recharge rebounds in considerable grade in the cost of energy generation for concept of fuel. (Author) 19. Flora planctónica de laguna Lagartos, Quintana Roo Planktonic flora from Lagartos Lagoon, Quintana Roo Directory of Open Access Journals (Sweden) Viridiana Margarita Nava-Ruiz 2012-09-01 Full Text Available Se presenta una lista de la flora planctónica de la laguna Lagartos, basada en la observación de muestras superficiales obtenidas entre noviembre de 2007 a septiembre de 2008. Las muestras se recolectaron con una botella Van Dorn de 2 litros en la parte central de la laguna; se registraron 67 taxa: 28 Bacillariophyta, 22 Cyanoprokaryota, 7 Chlorophyta, 6 Dinoflagellata, 2 Euglenophyta y 2 Cryptophyta. Las cianofitas dominaron durante todo el periodo de estudio, con una contribución mayor al 80% de la abundancia total del fitoplancton. Son nuevos registros para México 13 especies: Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum, Planktolyngbya contorta, Rhodomonas minuta, Amphidinium massartii, Ensiculifera cf. loeblichii, Heterocapsa cf. pseudotriquetra, Prorocentrum cassubicum, Licmophora normaniana, Fistulifera saprophila y Amphora richardiana. Todos los taxa listados se ilustran con microfotografías.The planktonic flora from Lagartos Lagoon, Quintana Roo, was examined based on the observation of samples collected from November 2007 to September 2008. The superficial samples were collected with a Van Dorn bottle of 2 L, in the core part of the lagoon. A total of 67 taxa were identified: 28 Bacillariophyta, 22 Cyanoprokaryota, 7 Chlorophyta, 6 Dinoflagellata, 2 Euglenophyta and 2 Cryptophyta. Nevertheless, the blue green algae dominated during all study period, with more of 80% to the total abundance of the phytoplankton. The species Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum, Planktolyngbya contorta, Rhodomonas minuta, Amphidinium massartii, Ensiculifera cf. loeblichii, Heterocapsa cf. pseudotriquetra, Prorocentrum cassubicum, Licmophora normaniana, Fistulifera saprophila and Amphora richardiana were recorded for the first time in Mexico. All the taxa are illustrated with microphotographs. 20. Development of an interactive model of the Laguna Verde nuclear power plant based on the RELAP/SCDAP code; Desarrollo del modelo interactivo de la central nucleoelectrica de Laguna Verde basado en el codigo RELAP/SCDAP Energy Technology Data Exchange (ETDEWEB) Salazar C, J.H.; Ramos P, J.C.; Salazar S, E.; Chavez M, C. [LAIRN, FI-UNAM, DEPFI Campus Morelos, Jiutepec, Morelos (Mexico)]. e-mail: [email protected] 2003-07-01 The present work describes the development of an interactive model of the Nuclear power plant of Laguna Verde (CNLV) based on the RELAP/SCDAP nuclear code, and it incorporation to a classroom simulator. The functional prototype it allows to make evaluations for operational transients and postulates accidents, with capacitation purposes, training, analysis and design. It emphasizes on the methodology used to establish the inter activity. Such methodology, is based on a modular structure in the one that multiple processes can be executed in an independent way and where the generated information is stored in segments of shared memory (characteristic that allows the UNIX operating system) and sent to the different processes by means of communication routines developed in C programming language. The utility of the system is demonstrated by means of the use of interactive display graphics (mimic diagrams, pictorials and tendency graphics) for the simultaneous dynamic visualization of the variables more significant that involve to the pattern of a transitory event type (for example failure of the controller of feeding water in a BWR reactor). Near with the interactive module, it was developed a model of the reactor of the CNLV for the code of better estimation RELAP/SCDAP. Finally the evaluation of the model is described, where it is interpreted in general form the behavior of those main variables that describe the stationary state, corroborating that follow the same tendency that those reported in the FSAR (Final Safety Analysis Report) of the Laguna Verde plant. The obtained results allow to conclude that the made development was satisfactory and that it presents enormous advantages regarding the capacity and time of analysis when using tools of visualization in real time of execution. (Author) 1. La ecología alimentaria del pez endémico Girardinichthys multiradiatus (Cyprinidontiformes: Goodeidae, en el Parque Nacional Lagunas de Zempoala, México Directory of Open Access Journals (Sweden) Patricia Trujillo-Jiménez 2006-12-01 Full Text Available Girardinichthys multiradiatus, conocido comúnmente como "mexcalpique" un pequeño pez endémico de la cuenca del río Lerma, cuya presencia en el parque Nacional Lagunas de Zempoala, sugiere una antigua conexión entre estos lagos y la cuenca. El área de distribución actual en la porción del valle de México y Toluca se ha visto reducida, por lo que este parque representa un refugio para la especie. Sin embargo, se conoce poco de la biología del mexcalpique. Presentamos datos sobre su dieta y hábitos alimentarios. El estudio se realizó en el Lago Acoyotongo del Parque Nacional Lagunas de Zempoala mediante muestreos estacionales. La identificación del contenido estomacal (97 ejemplares se llevó hasta el taxón más específico posible. Para la cuantificación se utilizaron los métodos numérico y frecuencia de aparición. La dieta general de esta especie se encuentra constituida por doce componentes alimenticios, de los cuales once son de origen animal. Himenópteros, colémbolos y quironómidos fueron los que presentaron los mayores porcentajes de ingestión y preferencia. Esta es una especie carnívora con tendencias insectívorasThe feeding ecology of the endemic fish Girardinichthys multiradiatus (Cyprinidontiformes: Goodeidae in Lagunas of Zempoala National Park, Mexico. Girardinichthys multiradiatus, locally known as "mexcalpique", is a small endemic fish of the Lerma river basin. Its presence in lakes (Zempoala suggests a long-standing connection between these lakes and the river basin. The current range of this species in the Mexico and Toluca valley appears to have been reduced, making this park a refuge for the species. Nevertheless, little is known about its biology. We studied its diet and feeding habits in Acoyotongo Lake, Lagunas de Zempoala National Park (19°01’30"-19°06’ N, 99°16’20"-99°21’ W where seasonal collections were carried out. The gut contents of 97 specimens were identified to the most specific 2. Limnology in El Dorado: some surprising aspects of the regulation of phytoplankton productive capacity in a high-altitude Andean lake (Laguna de Guatavita, Colombia Directory of Open Access Journals (Sweden) Jhon Donato 2012-09-01 Full Text Available High-altitude mountain lakes remain understudied, mostly because of their relative inaccessibility. Laguna de Guatavita, a small, equatorial, high-altitude crater lake in the Eastern Range of the Colombian Andes, was once of high cultural importance to pre-Columban inhabitants, the original location of the legendary El Dorado. We investigated the factors regulating the primary production in Laguna de Guatavita (4°58’50” N - 73°46’43” W, alt. 2 935m.a.s.l., area: 0.11km², maximum depth: 30m, during a series of three intensive field campaigns, which were conducted over a year-long period in 2003-2004. In each, standard profiles of temperature, oxygen concentration and light intensity were determined on each of 16-18 consecutive days. Samples were collected and analysed for chlorophyll and for biologically-significant solutes in GF/F-filtered water (NH4+, NO3- , NO2-; soluble reactive phosphorus. Primary production was also determined, by oxygen generation, on each day of the campaign. Our results showed that the productive potential of the lake was typically modest (campaign averages of 45-90mg C/m².h but that many of the regulating factors were not those anticipated intuitively. The lake is demonstrably meromictic, reminiscent of karstic dolines in higher latitudes, its stratification being maintained by solute- concentration gradients. Light penetration is poor, attributable to the turbidity owing to fine calcite and other particulates in suspension. Net primary production in the mixolimnion of Laguna de Guavita is sensitive to day-to-day variations in solar irradiance at the surface. However, deficiencies in nutrient availability, especially nitrogen, also constrain the capacity of the lake to support a phytoplankton. We deduced that Laguna de Guatavita is something of a limnological enigma, atypical of the common anticipation of a “mountain lake”. While doubtlessly not unique, comparable descriptions of similar sites elsewhere 3. A new Cassegrain calibration lamp unit for the Blanco Telescope Science.gov (United States) Points, S. D.; James, D. J.; Tighe, R.; Montané, A.; David, N.; Martínez, M. 2016-08-01 The f/8 RC-Cassegrain Focus of the Blanco Telescope at Cerro Tololo Inter-American Observatory, hosts two new instruments: COSMOS, a multi-object spectrograph in the visible wavelength range (350 - 1030nm), and ARCoIRIS, a NIR cross-dispersed spectrograph featuring 6 spectral orders spanning 0.8 - 2.45μm. Here we describe a calibration lamp unit designed to deliver the required illumination at the telescope focal plane for both instruments. These requirements are: (1) an f/8 beam of light covering a spot of 92mm diameter (or 10 arcmin) for a wavelength range of 0.35μm through 2.5μm and (2) no saturation of flat-field calibrations for the minimal exposure times permitted by each instrument, and (3) few saturated spectral lines when using the wavelength calibration lamps for the instruments. To meet these requirements this unit contains an adjustable quartz halogen lamp for flat-field calibrations, and one hollow cathode lamp and four penray lamps for wavelength calibrations. The wavelength calibration lamps are selected to provide optimal spectral coverage for the instrument mounted and can be used individually or in sets. The device designed is based on an 8-inch diameter integrating sphere, the output of which is optimized to match the f/8 calibration input delivery system which is a refractive system based on fused-silica lenses. We describe the optical design, the opto-mechanical design, the electronic control and give results of the performance of the system. 4. Limnología e ictiofauna de la laguna José María (Córdoba, Argentina, con especial referencia al pejerrey (Odontesthes bonariensis -Valenciennes, 1835- Directory of Open Access Journals (Sweden) M. Mancini 2016-09-01 Full Text Available La región sur de la provincia de Córdoba presenta numerosas lagunas cuyo origen y salinidad varían ampliamente. Muchos de estos ambientes son utilizados para la pesca recreativa del pejerrey (Odontesthes bonariensis. El objetivo del presente trabajo fue caracterizar la calidad del agua y determinar la diversidad del zooplancton y de la ictiofauna con especial referencia a O. bonariensis, de la laguna José María (34º50’17’’S, 63º37’23’’O. Este ambiente se ubica en la cuenca del río Quinto (Córdoba y está comunicado con numerosas lagunas. Se analizaron in situ (n=8, el pH, el oxígeno, la temperatura y transparencia del agua y se tomaron muestras de agua y zooplancton para su análisis en laboratorio. Para la captura de peces se utilizaron redes de enmalle, arrastre, trampa y espineles. La profundidad promedio fue de 1,99 m, con un máximo de 2,20 m. Los registros medios del pH, oxígeno disuelto, temperatura y transparencia fueron 8,51, 9,03 mg/L, 24,3 ºC y 44 cm respectivamente. Por su transparencia, la laguna fue caracterizada como “turbia”. El agua se clasificó como oligohalina (4,09 g/L, sulfatada-sódica y muy dura (484 ppm de CO3Ca. El zooplancton estuvo representado por 3 especies de crustáceos y 7 de rotíferos. Entre los primeros, Metacyclops mendocinus fue el que registró la mayor densidad (162,2 ind/L, mientras que entre los rotíferos fue Brachionus plicatilis con 482,7 ind/L. Se capturaron 12 especies de peces, pertenecientes a 5 órdenes y 9 familias (Shannon = 2,23 bits. El pejerrey fue la especie de mayor abundancia (50,8% y junto al sabalito Cyphocharax voga y la carpa Cyprinus carpio representaron el 85 % del total de biomasa de los peces capturados. Los parámetros poblacionales de O. bonariensis fueron: Peso= 0,0000047081*LEst3,178 (R2=0,99, n=116; longitud total= 5,854+LEst*1,168 (R2= 0,99, n= 117; LEst(t= 489,02 (1-e-0,225(t-0,46 y W(t= 1647,5 (1- e-0,225(t-0,463,177. 5. "Don Kihotõ" nazõvajut lutshshih / Boris Tuch Index Scriptorium Estoniae Tuch, Boris, 1946- 2003-01-01 Lõppenud festivali FIPRESCI auhinna sai türgi film "Kauge" ("Uzak") : režissöör Nuri Bilge Ceylan. Rahvusvaheline filmiklubide föderatsioon (FICC) andis oma auhinna Don Quijote Andrei Zvjagintsevi filmile "Tagasitulek" ("Vozvrashtshenije") ja eriauhinna hiinlase Chen Kaige filmile "Üheskoos" ("Han ni zai ylki") 6. Deoxynivalenol (DON Contamination of Feed and Grinding Fineness: Are There Interactive Implications on Stomach Integrity and Health of Piglets? Directory of Open Access Journals (Sweden) Sven Dänicke 2017-01-01 Full Text Available The common feed contaminant deoxynivalenol (DON was reported to influence the morphology of the pars nonglandularis (PN of porcine stomach. Moreover, finely ground feed is known to trigger the development of ulcers and other pathologies of PN while coarsely ground feed protects from such lesions. The interactions between grinding fineness and DON contamination of feed were not examined so far. Therefore, both finely and coarsely ground feeds were tested either in the absence or presence of a DON contaminated wheat on growth performance and health of rearing piglets, including stomach integrity. DON contamination significantly reduced feed intake and serum albumin concentration with this effect being more pronounced after feeding the coarsely ground feed. Albeit at a higher level, albumin concentration was also reduced after feeding the finely ground and uncontaminated feed. Finely ground and DON-contaminated feed caused a significantly more pronounced lymphoplasmacytic infiltration both of PN and pars glandularis, partly paralleled by lymph follicle formation and detritus filled foveolae and tubes suggesting a local immune response probably triggered by epithelial lesions. It is concluded that DON contamination of feed exacerbates the adverse effects of finely ground feed on stomach mucosal integrity. 7. Deoxynivalenol (DON) Contamination of Feed and Grinding Fineness: Are There Interactive Implications on Stomach Integrity and Health of Piglets? Science.gov (United States) Dänicke, Sven; Beineke, Andreas; Berk, Andreas; Kersten, Susanne 2017-01-01 The common feed contaminant deoxynivalenol (DON) was reported to influence the morphology of the pars nonglandularis (PN) of porcine stomach. Moreover, finely ground feed is known to trigger the development of ulcers and other pathologies of PN while coarsely ground feed protects from such lesions. The interactions between grinding fineness and DON contamination of feed were not examined so far. Therefore, both finely and coarsely ground feeds were tested either in the absence or presence of a DON contaminated wheat on growth performance and health of rearing piglets, including stomach integrity. DON contamination significantly reduced feed intake and serum albumin concentration with this effect being more pronounced after feeding the coarsely ground feed. Albeit at a higher level, albumin concentration was also reduced after feeding the finely ground and uncontaminated feed. Finely ground and DON-contaminated feed caused a significantly more pronounced lymphoplasmacytic infiltration both of PN and pars glandularis, partly paralleled by lymph follicle formation and detritus filled foveolae and tubes suggesting a local immune response probably triggered by epithelial lesions. It is concluded that DON contamination of feed exacerbates the adverse effects of finely ground feed on stomach mucosal integrity. PMID:28045426 8. RICKETS AT THE MEDICI COURT OF FLORENCE: THE CASE OF DON FILIPPINO (1577-1582). Science.gov (United States) Castagna, Maura; Giuffra, Valentina; Fattori, Silvia; Vitiello, Angelica; Caramella, Davide; Giustini, Davide; Fornaciari, Gino 2014-01-01 Among the children found in the crypt of the Grand Duke Giangastone in S. Lorenzo Basilica (Florence), the skeletal remains of a 5-year-old child still wearing his fine high social status clothing were recovered. This child of the Medici family was identified as Don Filippino (1577-1582), son of the Grand Duke Francesco I (1541-1587) and Giovanna from Austria (1547 - 1578). The prince showed several pathological deformities of the cranial and post-cranial skeleton, including enlargement of the cranium, thinning of the cranial vault bones (craniotabes), platybasia and marked bending of femora, tibiae and fibulae. Differential diagnosis suggests that Don Filippino was affected by rickets. The occurrence of this metabolic disease related to vitamin D deficiency in a Renaissance high social class individual can be explained by the practice of very prolonged breast-feeding, up until two years of age. Maternal milk contains insufficient vitamin D ratios and retarded weaning severely exposes children to a higher risk of developing rickets, especially if dietary habits are combined with inadequate exposure to sunlight. Historical sources describe Don Filippino as frail and sickly, with frequent illnesses and persistent slight fevers, and it can be supposed that the child was frequently confined indoors, especially in the cold season. Integration of osteoarchaeological evidence with historical documentation suggests that bone lesions observed in the skeletal remains of Don Filippino are compatible with a diagnosis of rickets, caused by the custom of prolonged breast-feeding associated with inadequate sunlight exposure to sunlight. Historical sources describe Don Filippino as frail and sickly, with frequent illnesses and persistent slight fevers, and it can be supposed that the child was frequently confined indoors, especially in the cold season. Integration of osteoarchaeological evidence with historical documentation suggests that bone lesions observed in the skeletal 9. Don Carlos: Variations of Tragic from Schiller to Verdi Directory of Open Access Journals (Sweden) Fabio Vittorini 2017-11-01 Full Text Available In 1867 Giuseppe Verdi makes a grand opéra out of the dramatic poem Don Carlos, Infant von Spanien (1787 by Friedrich von Schiller. The workshop of Don Carlos lasts twenty years, from 1866 to 1886, when Verdi (reopens and closes several other workshops (Simon Boccanegra, La forza del destino, Aida, Requiem, Otello, creating a porous work in progress, whose analysis keeps giving us surprises. The libretto by Joseph Méry et Camille Du Locle, under the supervision of the composer, is a palimpsest where, under the official text referable to the common historical nucleus and its best known literary versions, some hidden or deleted heterogeneous texts appear, in a supranational, multilinguistic, intercultural and intertextual dimension, not always stirring along the road of a locatable derivation, of a voluntary imitation, but sometimes taking the shape of an unpredictable dissemination. 10. Nuevas evidencias geofísicas de la existencia de una caldera cubierta en laguna Pozuelos: Puna norte OpenAIRE Claudia B Prezzi; Federico Lince Klinger 2010-01-01 En el extremo sur de la cuenca de laguna de Pozuelos aflora el complejo volcánico Pan de Azúcar. El mismo está integrado por varios centros eruptivos de composición dacítica y morfología dómica que poseen una edad de ~12 Ma. Interpretaciones previas de líneas sísmicas y un relevamiento magnetométrico detallado indicaron la presencia de cuerpos intrusivos no aflorantes. La determinación de la existencia de nuevos cuerpos intrusivos no aflorantes en la zona resulta de interés debido a que: 1) e... 11. Transcriptome analysis of the human T lymphocyte cell line Jurkat and human peripheral blood mononuclear cells exposed to deoxynivalenol (DON): New mechanistic insights Energy Technology Data Exchange (ETDEWEB) Katika, Madhumohan R. [RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen (Netherlands); Department of Health Risk Analysis and Toxicology, Maastricht University (Netherlands); Netherlands Toxicogenomics Centre (Netherlands); Hendriksen, Peter J.M. [RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen (Netherlands); Netherlands Toxicogenomics Centre (Netherlands); Shao, Jia [RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen (Netherlands); Department of Health Risk Analysis and Toxicology, Maastricht University (Netherlands); Netherlands Toxicogenomics Centre (Netherlands); Loveren, Henk van [Department of Health Risk Analysis and Toxicology, Maastricht University (Netherlands); National Institute for Public Health and the Environment (RIVM), Bilthoven (Netherlands); Netherlands Toxicogenomics Centre (Netherlands); Peijnenburg, Ad, E-mail: [email protected] [RIKILT-Institute of Food Safety, Wageningen University and Research Centre, Wageningen (Netherlands); Netherlands Toxicogenomics Centre (Netherlands) 2012-10-01 Deoxynivalenol (DON) or vomitoxin is a commonly encountered type-B trichothecene mycotoxin, produced by Fusarium species predominantly found in cereals and grains. DON is known to exert toxic effects on the gastrointestinal, reproductive and neuroendocrine systems, and particularly on the immune system. Depending on dose and exposure time, it can either stimulate or suppress immune function. The main objective of this study was to obtain a deeper insight into DON-induced effects on lymphoid cells. For this, we exposed the human T-lymphocyte cell line Jurkat and human peripheral blood mononuclear cells (PBMCs) to various concentrations of DON for various times and examined gene expression changes by DNA microarray analysis. Jurkat cells were exposed to 0.25 and 0.5 μM DON for 3, 6 and 24 h. Biological interpretation of the microarray data indicated that DON affects various processes in these cells: It upregulates genes involved in ribosome structure and function, RNA/protein synthesis and processing, endoplasmic reticulum (ER) stress, calcium-mediated signaling, mitochondrial function, oxidative stress, the NFAT and NF-κB/TNF-α pathways, T cell activation and apoptosis. The effects of DON on the expression of genes involved in ER stress, NFAT activation and apoptosis were confirmed by qRT-PCR. Other biochemical experiments confirmed that DON activates calcium-dependent proteins such as calcineurin and M-calpain that are known to be involved in T cell activation and apoptosis. Induction of T cell activation was also confirmed by demonstrating that DON activates NFATC1 and induces its translocation from the cytoplasm to the nucleus. For the gene expression profiling of PBMCs, cells were exposed to 2 and 4 μM DON for 6 and 24 h. Comparison of the Jurkat microarray data with those obtained with PBMCs showed that most of the processes affected by DON in the Jurkat cell line were also affected in the PBMCs. -- Highlights: ► The human T cell line Jurkat and human 12. El don: entre las prácticas intersticiales y el solidarismo Directory of Open Access Journals (Sweden) ADRIÁN SCRIBANO 2014-08-01 Full Text Available El presente trabajo busca hacer evidente al solidarismo como la "pérdida del don", conforme expuesto por Mauss, en el contexto de la situación colonial, de los procesos de expansión capitalista en la actualidad. Como objeto de análisis y mediación hermenéutica, hemos seleccionado a la Responsabilidad Social Empresarial (RSE como una forma del solidarismo cuyas prácticas llevan a un conjunto de situaciones que pueden describirse como pornográficas. Para lograr el objetivo explicitado, hemos seguido la siguiente estrategia argumentativa: a se sintetizan algunas pocas coordenadas de carácter teóricos que permitan entender la centralidad del don y se explicita nuestra idea de solidarismo, b se realiza un triple análisis: de la conceptualización de la RSE y de las experiencias de RSE de algunas corporaciones internacionales en Argentina; y c se exponen nuestras ideas sobre prácticas intersticiales en tanto hiatos que quiebran a la economía política de la moral como una totalidad que demanda la "pérdida" de todo tipo de don. 13. To report the obtained results in the simulation with the FCS-11 and Presto codes of the two first operation cycles of the Laguna Verde Unit 1 reactor; Reportar los resultados obtenidos en la simulacion con los codigos FCS-11 y PRESTO de los dos primeros ciclos de operacion del reactor Laguna Verde Unidad 1 Energy Technology Data Exchange (ETDEWEB) Montes T, J.L.; Moran L, J.M.; Cortes C, C.C 1990-08-15 The objective of this work is to establish a preliminary methodology to carry out analysis of recharges for the reactor of the Laguna Verde U-1, by means of the evaluation of the state of the reactor core in its first two operation cycles using the FCS2 and Presto-B codes. (Author) 14. Rehabilitation and modernization project of units 1 and 2 of Laguna Verde Nuclear Power Plant. A strengthening project to 120%. (2nd phase) International Nuclear Information System (INIS) Liebana, B.; Merino, A.; Garcia, J. L.; Gomez, M.; Martinez, I.; Ruiz, L. 2010-01-01 The power increase of the Laguna Verde Nuclear Power Plant is a project for the rehabilitation and modernization of the turbo and associated equipment to get an increase of its power and of its service life. The project scope includes the design, the engineering, the equipment supply, the installation, the testing and the commissioning. This article presents the work of the second phase. 15. Upgrade the intervention levels derived for water and foods, to be include in the PERE 607 procedure the external radiological emergency plan in the Laguna Verde nuclear power plant International Nuclear Information System (INIS) Llado Castillo, R.; Aguilar Pacheco, R. 1998-01-01 The work shows the results obtained in the upgrade the intervention levels derived for water and foods, to be include in the PERE 607 procedure the external radiological emergency plan in the Laguna Verde nuclear power plant 16. Ageing Management Review of the reactor pressure vessels in Laguna Verde NPP International Nuclear Information System (INIS) Gris Cruz, Magdalena; Arganis, Carlos R.J.; Medina Almazan, A. Liliana 2012-01-01 In the present paper, for both units of Laguna Verde Nuclear Power Plant (LVNPP), the Ageing Management Review of the reactor pressure Vessel was carried out, including the identification of the intended functions, the materials and the environments. The evaluation of the ageing effect/mechanism and the Aging management programs currently implemented were prepared. The most important aging effects/ mechanisms are: loss of fracture toughness due to neutron irradiation embrittlement, fatigue, stress corrosion cracking (SCC), general corrosion and erosion-corrosion. The neutron irradiation embrittlement is managed by the reactor vessel materials surveillance program. The fatigue is a Time Limited Aging Analysis (TLAA), for which is necessary to calculate some fatigue usage factors. SCC is managed by, the In service inspections (ISI) program, but also by the Water Chemistry program, including, currently, On Line Noble Chem. The water chemistry program also manages General Corrosion and erosion-corrosion. The results were compared with the GALL report. (author) 17. Large wood budget assessment along a gravel bed river affected by volcanic eruption: the Rio Blanco study case (Chile). Science.gov (United States) Oss-Cazzador, Daniele; Iroume, Andres; Lenzi, Mario; Picco, Lorenzo 2016-04-01 Wood in riverine environments exerts different functions on ecological and geomorphic settings, influencing morphological processes, and increasing risks for sensitive structures. Large wood (LW) is defined as wood material, dead or alive, larger than 10 cm in diameter and 1 m in length. Natural hazards can strongly increase the presence of LW in waterways and flood events can transport it affecting the ecosystem and landscape. This study aims to increase the knowledge of wood budget, considering the effects of two subsequent slight flood events along a sub-reach of the Rio Blanco gravel bed river , in Chilean Patagonia, strongly affected by the eruption of Chaiten volcano in 2008. The volcanic eruption affected almost 3,5 km 2 of evergreen forest on the southern (left) bank, because of primary direct effects from pyroclastic density currents and lahar-floods that caused deposition up to 8 m of reworked tephra, alluvium, and wood on floodplains and terrace along the Rio Blanco. After the eruption, there was a considerable increase of LW into the main channel: into the bankfull channel, volume exceeds 100 m 3 /ha. Field surveys were carried out in January and March 2015, before and after two slight flood events (Recurrence Intervals lower than 1 year). The pre-event phase permitted to detect and analyze the presence of LW into the study area, along a 80 m-long reach of Rio Blanco (7500 m 2 . Every LW element was manually measured and described, a numbered metal tag was installed, and the position was recorded by GPS device. In January, there was a total amount of 113 m 3 /ha, 90% accumulated in LW jams (WJ) and 10% as single logs. The LW was characterized by mean dimensions of 3,36 m height, 0,25 m diameter and 0,26 m 3 volume, respectively. The WJ are characterized by wide range of dimension: volume varies from 0,28 m 3 to 672 m 3 , length from 1,20 m to 56 m, width from 0,40 m to 8,70 m and height from 0,20 m to 3 m, respectively. After the flood events, field 18. The Rhetoric of Madness in Kathy Acker’s Don Quixote Directory of Open Access Journals (Sweden) Claudia Cao 2017-07-01 Full Text Available This essay examines the rhetorical experimentation of Don Quixote by Kathy Acker, starting from a theoretical concept central in the author’s thought: her search for a “language of the body”. A brief introduction to Kathy Acker’s plagiaristic poetics frames her narrative strategies between postmodern rewriting and pastiche. It shows the way in which her Don Quixote transposes the representative scheme of the chivalric quest into the contemporary value system with the aim of questioning Cervantes’ text as one of the canonical works of the Western literary tradition. The following section deepens three focal concepts of Acker’s theoretical works – body, madness, and norm – illuminating the connections between her rhetorical experimentation and the works by Luce Irigaray and Judith Butler. Finally, the paper will demonstrate how these concepts in Acker's rewriting of Don Quixote are strictly related to paradox, which she uses in order to actualize a “language of the body”: in the passage from the former novel to the postmodern work, madness has become the device which, from the semantic level to the rhetorical one, expresses Acker’s idea of language of the body, as an alternative and in contrast to the canonical language of the logos. 19. Citrus Essential Oil of Nigeria Part IV: Volatile Constituents of Leaf Oils of Mandarins (Citrus Reticulata Blanco From Nigeria Directory of Open Access Journals (Sweden) Adeleke A. Kasali 2010-07-01 Full Text Available The chemical composition of hydrodistilled oils obtained from the leaves of six Citrus reticulata Blanco (mandarin cultivars grown in Nigeria were examined by GC and GC/MS, the result of their chemical composition were further submitted to cluster analysis. Fifty seven constituents were characterized accounting for 88.2 - 96.7% of the total oils. Sabinene, g -terpinene, P-cymene, d -3-carene and (E- b -ocimene were observed in great variability in all the oils. Other constituents include linalool, myrcene, terpinen-4-ol and cis-sabinenehydrate. In addition, limonene, terpinolene, b -pinene, and a -pinene were also detected in appreciable concentrations. b -sinensal and a -sinensal were isolated by preparative GC and characterized by one- and two-dimensional NMR techniques. 20. Perspectives of the central Laguna Verde after Fukushima for the period 2012 at the 2015 in operation and maintenance International Nuclear Information System (INIS) Rivera C, A. 2012-10-01 The Nuclear Power Plants Management of the Federal Commission of Electricity in Mexico by means an internal analysis confronts the threat to the nuclear industry of the event of Fukushima that affected the public opinion, and the emission of new regulations. This situation demands to improve the results of the operation and maintenance of the nuclear power plant of Laguna Verde, to contribute value with their excellence in the acting to the nuclear option in Mexico. The internal analysis defined with clarity the perspectives based on weaknesses and strengths of the operation (monitoring and control of on-line parameters), and in the maintenance (sustained by the planning), enriched with the external experiences emitted by the institutes INPO and WANO for the nuclear industry, with all this strategic objectives 2012 to 2015 were presented and the initiatives as the extension of the useful life to 20 years more, as well as the focused actions to diminish the threat that the event of Fukushima influenced negatively in the public opinion, by means the diffusion of the good results that can be obtained in the nuclear power plant of Laguna Verde between 2012 and 2015, taking advantage of its modernized power of 810 MW-hour for each generating unit, doing visible that the Project of Extended Power Increase is a generation reality of 120% of the original value, to be able to enter at the excellence levels of the nuclear world. (Author) 1. Co-Contamination of DON and NIV in Domestic Flour in Japan: Survey, Intake, Reduction and Rapid Assay Science.gov (United States) Nivalenol (NIV) and Deoxynivalenol (DON) are trichothecene mycotoxins produced by Fusarium spp. that contaminate mainly cereal crops, such as wheat, barley, and maize. These mycotoxins are serious health hazards to humans and domestic animals. In Japan, there have been many reports of DON and NIV ... 2. Don Quixote an Celia: the desire to live other lives Directory of Open Access Journals (Sweden) María Jesús Fraga Fernández-Cuevas 2012-12-01 Full Text Available The present study explores the parallelisms between Don Quixote and Elena Fortun’s novels Celia. First, it enumerates the various activities that prove the author’s interest in Cervantes and his work, as well as the possible intervention of her mentor, Maria Martinez Sierra, in the genesis of the child’s character. Both novels, of dialogical nature, share an episodic structure articulated by a weak storyline. Its protagonists are animated by the desire to live the lives of the characters of their favorite readings. They confuse fantasy and reality causing situations whose results are almost always adverse. If Don Quixote dies back to the reason, so will Celia, the girl, with her entry into adulthood by resigning her fantasies, which will be taken up by new generations of children. 3. IDEA: An Interdisciplinary Unit Comparing "Don Quixote" to "Hamlet." Science.gov (United States) Harris, Mary J. G. 2001-01-01 Describes an idea for teaching language through content-based instruction in which a high school Spanish class studying a shortened abridged version of Cervantes'"Don Quixote" and an English class reading Shakespeare's "Hamlet," did a simple comparative analysis of the two texts. (Author/VWL) 4. Biología del pejerrey Odontesthes bonariensis (Pisces, Atherinopsidae de la laguna Los Charos (Córdoba, Argentina Directory of Open Access Journals (Sweden) Miguel Mancini 2008-12-01 Full Text Available El pejerrey Odontesthes bonariensis es la especie más importante de las pesquerías del centro de Argentina. Se estudio la captura por unidad de esfuerzo (CPUE, la condición corporal, el crecimiento y la alimentación de O. bonariensis de la laguna pampeana Los Charos (34º28´S, 64º23´W, 240 ha, ubicada en la provincia de Córdoba. Se realizaron cuatro muestreos estacionales en el periodo 2002-2003. Para la captura de peces se utilizaron redes de arrastre y enmalle. Se capturaron 2862 ejemplares de un rango de talla comprendido entre 38 y 380 mm de longitud estándar (LSt. La CPUE promedio fue de 74,3(±71,0kg/20 hs de tendido de red. La relación LSt-peso presentó diferencias significativas entre épocas del año (P< 0,01. Los índices de condición corporal estuvieron dentro de los límites de referencia de la especie. El crecimiento calculado fue: LSt(t=459,8*[1–exp(-0,3105*(t-0,175]. La relación LSt–Longitud total (LT fue: LT(mm=8,23+LSt*1,14 (n=283; R2=0,99. El zooplancton constituyó un ítem alimenticio secundario en los peces jóvenes. En los ejemplares de 3+ años de vida se observó un marcado canibalismo, situación que explicaría en parte su mejor condición corporal. La laguna Los Charos presenta una elevada producción de O. bonariensis. 5. Characterization of Pustular Mats and Related Rivularia-Rich Laminations in Oncoids From the Laguna Negra Lake (Argentina Directory of Open Access Journals (Sweden) Estela C. Mlewski 2018-05-01 Full Text Available Stromatolites are organo-sedimentary structures that represent some of the oldest records of the early biosphere on Earth. Cyanobacteria are considered as a main component of the microbial mats that are supposed to produce stromatolite-like structures. Understanding the role of cyanobacteria and associated microorganisms on the mineralization processes is critical to better understand what can be preserved in the laminated structure of stromatolites. Laguna Negra (Catamarca, Argentina, a high-altitude hypersaline lake where stromatolites are currently formed, is considered as an analog environment of early Earth. This study aimed at characterizing carbonate precipitation within microbial mats and associated oncoids in Laguna Negra. In particular, we focused on carbonated black pustular mats. By combining Confocal Laser Scanning Microscopy, Scanning Electron Microscopy, Laser Microdissection and Whole Genome Amplification, Cloning and Sanger sequencing, and Focused Ion Beam milling for Transmission Electron Microscopy, we showed that carbonate precipitation did not directly initiate on the sheaths of cyanobacterial Rivularia, which dominate in the mat. It occurred via organo-mineralization processes within a large EPS matrix excreted by the diverse microbial consortium associated with Rivularia where diatoms and anoxygenic phototrophic bacteria were particularly abundant. By structuring a large microbial consortium, Rivularia should then favor the formation of organic-rich laminations of carbonates that can be preserved in stromatolites. By using Fourier Transform Infrared spectroscopy and Synchrotron-based deep UV fluorescence imaging, we compared laminations rich in structures resembling Rivularia to putatively chemically-precipitated laminations in oncoids associated with the mats. We showed that they presented a different mineralogy jointly with a higher content in organic remnants, hence providing some criteria of biogenicity to be searched 6. Don Yllán and the Egyptian Sorcerer: Vernacular commonality and literary diversity in medieval Castile Directory of Open Access Journals (Sweden) Wacks, David A. 2005-12-01 Full Text Available In this article the author compares the exemplo of Don Yllán and the Deán de Santiago -no. 11 in Don Juan Manuel's Conde Lucanor (ca. 1335- with an earlier Hebrew analogue found in the Hebrew Mešal Haqadmonī (ca. 1285 of fellow Castilian author Isaac ibn Sahula. A thorough analysis of the rhetorical and narrative style of both versions reveals that the two tales shared a common source in Castilian oral tradition. The appearance of the tale in an earlier Hebrew text from Castile (the only other known version in any language calls into question the originality of Don Juan Manuel's most famous exemplo, suggesting a productive interplay between a common oral tradition in Castilian and coexisting literary traditions in Hebrew and Castilian. En este artículo, el autor compara el exemplo de Don Yllán y el Deán de Santiago -n.° 11 en el Conde Lucanor (ca. 1335 de Don Juan Manuel- con una versión anterior en la obra hebrea, Mešal Haqadmonī (ca. 1285 de otro autor castellano, Isaac ibn Sahula. Un análisis cuidadoso del estilo narrativo y retórico de ambas versiones revela que las dos comparten una fuente común en la tradición oral castellana. La aparición del cuento en un texto hebreo anterior de Castilla (la única versión conocida en cualquier otra lengua cuestiona la originalidad literaria del más famoso exemplo de Don Juan Manuel, y sugiere un intercambio productivo entre una tradición oral común castellana y tradiciones literarias hebreas y castellanas coexistentes. 7. Society and Environment Interaction. The Environment of the Laguna de los Tollos (Western Andalusia, 13th-15th Centuries Directory of Open Access Journals (Sweden) Emilio MARTÍN GUTIÉRREZ 2014-12-01 Full Text Available Environment of the Laguna de los Tollos is studied between 13th and 15th Centuries. The research, which aims to analyse the interaction environment-society, is part of a project that will deepen the knowledge of wetlands in this geographical area. In these ecosystems rural communities took advantage with their farmland for hunting, herding, fishing and gathering resources in riparian areas. The chosen chronological period includes a wide range of changes that had a direct impact on the management and organization of rural landscapes. 8. Estudio de percepción y análisis de evaluación sensorial del mezcal de Laguna Seca OpenAIRE Andrade Luna, Silvia Aurora 2016-01-01 Se analizó un estudio sobre percepción y la evaluación sensorial del mezcal artesanal elaborado en el municipio de Charcas, San Luis Potosí en la Fábrica de mezcal Laguna Seca. La valoración consistió en describir sensorialmente y determinar el nivel de aceptación por un grupo de estudio, con el propósito de generar una base de la calidad sensorial que permita a los productores del mezcal compararlo con otros mezcales. Se tomaron tres mezcales de comparación: mezcal joven, reposado ... 9. Validation of a new software version for monitoring of the core of the Unit 2 of the Laguna Verde power plant with ARTS; Validacion de una nueva version del software para monitoreo del nucleo de la Unidad 2 de la Central Laguna Verde con ARTS Energy Technology Data Exchange (ETDEWEB) Calleros, G.; Riestra, M.; Ibanez, C.; Lopez, X.; Vargas, A.; Mendez, A.; Gomez, R. [CFE, Central Nucleoelectrica de Laguna Verde, Alto Lucero, Veracruz (Mexico)]. e-mail: [email protected] 2005-07-01 In this work it is intended a methodology to validate a new version of the software used for monitoring the reactor core, which requires of the evaluation of the thermal limits settled down in the Operation Technical Specifications, for the Unit 2 of Laguna Verde with ARTS (improvements to the APRMs, Rod Block Monitor and Technical specifications). According to the proposed methodology, those are shown differences found in the thermal limits determined with the new versions and previous of the core monitoring software. Author) 10. Pemodelan Enterprise Architecture Sistem Informasi Akademik SMA PL Don Bosko Semarang Dengan Framework Zachman Directory of Open Access Journals (Sweden) Maria Alfonsa Chintia Dea Prananingrum 2017-05-01 Full Text Available Abstrak SMA PL Don Bosko Semarang belum dapat memanfaatkan teknologi komputer secara optimal karena masih menggunakan cara manual dalam pengelolaan berbagai macam data akademik sehingga memberikan masalah seperti lambatnya dalam pembuatan laporan yang menyulitkan kepala sekolah dalam pengambilan keputusan. Oleh sebab itu, SMA PL Don Bosko Semarang membutuhkan Sistem Informasi Akademik untuk memberikan kemudahan dalam mengelola berbagai macam data akademik secara terintegrasi serta memberikan layanan yang lebih baik kepada siswanya. Sebuah model architecture enterprise Sistem Informasi Akademik dibutuhkan agar meminimalisir kegagalan ketika menerapkan sistem tersebut sekaligus dapat berjalan sesuai kebutuhan di SMA PL Don Bosko Semarang. Metode analisis dalam penelitian ini menggunakan Framework Zachman yang memberikan pondasi dalam membantu menyediakan struktur dasar organisasi sehingga dapat mendukung perancangan dan pengembangan sistem informasi suatu organisasi. Hasil dari penelitian ini berupa blueprint (cetak biru pemodelan Sistem Informasi Akademik. Kata kunci— sistem informasi akademik, architecture enterprise, framework zachman, bluprint 11. Population fluctuations of Pyrodinium bahamense and Ceratium furca (Dinophyceae in Laguna Grande, Puerto Rico, and environmental variables associated during a three-year period Directory of Open Access Journals (Sweden) Miguel P. Sastre 2013-12-01 Full Text Available Bioluminescent bays and lagoons are unique natural environments and popular tourist attractions. However, the bioluminescence in many of these water bodies has declined, principally due to anthropogenic activities. In the Caribbean, the bioluminescence in these bays and lagoons is mostly produced by the dinoflagellate Pyrodinium bahamense var. bahamense. Laguna Grande is one of the three year-round bioluminescent water bodies in Puerto Rico that are known to remain but P. bahamense var. bahamense density fluctuations have not been studied. In this study we describe water quality parameters and density fluctuations of the most common dinoflagellates in Laguna Grande, P. bahamense var. bahamense and Ceratium furca, over a three-year period. For this, three sampling stations were established in Laguna Grande from which water samples were collected in triplicate and analyzed for temperature, phosphates, nitrates, salinity, water transparency, fluorescence, and dinoflagellate densities, at the water surface and at 2m depth, from May 2003 to May 2006. The results showed a density fluctuation pattern for P. bahamense var. bahamense, where higher densities were observed mainly from April to September, and lower densities from October to February. Density fluctuations of C. furca were more erratic and a repetitive pattern was not observed. Densities of P. bahamense var. bahamense ranged from 0.48 to 90 978 cells/L and densities of C. furca ranged from 0 to 11 200 cells/L. The mean population density throughout the sampling period was significantly higher in P. bahamense var. bahamense (mean=18 958.5 cells/L than in C. furca (mean=2 601.9 cells/L. Population densities of P. bahamense var. bahamense were negatively correlated with C. furca densities during the first year of sampling; however, they were positively correlated during the third year. Non-significant differences between surface and 2m depth samples were observed for temperature 12. Comparative transcriptional survey between self-incompatibility and self-compatibility in Citrus reticulata Blanco. Science.gov (United States) Ma, Yuewen; Li, Qiulei; Hu, Guibing; Qin, Yonghua 2017-04-20 Seedlessness is an excellent economical trait, and self-incompatibility (SI) is one of important factors resulting in seedless fruit in Citrus. However, SI molecular mechanism in Citrus is still unclear. In this study, RNA-Seq technology was used to identify differentially expressed genes related to SI reaction of 'Wuzishatangju' (Citrus reticulata Blanco). A total of 35.67GB raw RNA-Seq data was generated and was de novo assembled into 50,364 unigenes with an average length of 897bp and N50 value of 1549. Twenty-three candidate unigenes related to SI were analyzed using qPCR at different tissues and stages after self- and cross-pollination. Seven pollen S genes (Unigene0050323, Unigene0001060, Unigene0004230, Unigene0004222, Unigene0012037, Unigene0048889 and Unigene0004272), three pistil S genes (Unigene0019191, Unigene0040115, Unigene0036542) and three genes (Unigene0038751, Unigene0031435 and Unigene0029897) associated with the pathway of ubiquitin-mediated proteolysis were identified. Unigene0031435, Unigene0038751 and Unigene0029897 are probably involved in SI reaction of 'Wuzishatangju' based on expression analyses. The present study provides a new insight into the molecular mechanism of SI in Citrus at the transcriptional level. Copyright © 2017 Elsevier B.V. All rights reserved. 13. Vivisection au ralenti: Don DeLillo’s Point Omega Directory of Open Access Journals (Sweden) Ruxanda BONTILĂ 2014-12-01 Full Text Available Reading a Don DeLillo is like walking on glass, that is, you need hold your breath so that nothing could deter you from focusing on the mission, if you want to keep safe and mostly sound. The writer’s latest novel, Point Omega (2010, is no exception in that its author engages once more in the exercise of stripping away all surfaces so as to let us see into the terror of what he calls “makeshift reality”—his characters’ and ours. The claims I advance and substantiate in the essay, refer to (1 how a fluid chronology sustained by framing devices adds to the understanding of the construct of a novel/film in progress; (2 how the shifting narrative perspective ensures a vivisectionist’s look into the body of life/death/world. Don DeLillo’s novel is another terrifying X-ray of war/life/death as agonizing nothingness which literature in its ‘late-phase’ is meant to cure. 14. Report on the Fourth Reactor Refueling. Laguna Verde Nuclear Central. Unit 1. April-May 1995; Informe de la Cuarta Recarga de Combustible. Central Laguna Verde. Unidad 1. Abril-Mayo 1995 Energy Technology Data Exchange (ETDEWEB) Mendoza L, A; Flores C, E; Lopez G, C P.F. 1996-12-31 The fourth refueling of the Unit 1 of Laguna Verde Nuclear Central was executed in the period of April 17 to May 31 of 1995 with the participation of a task group of 358 persons, included technicians and radiation protection officials and auxiliaries.The radiation monitoring and radiological surveillance to the workers was present length ways the refueling process and always attached to the ALARA criteria. The check points for radiation levels were set at: primary container or dry well, reloading floor, decontamination room (level 10.5), turbine building and radioactive waste building. To take advantage of the refueling process, rooms 203 and 213 of the turbine buildings were subject to inspection and maintenance work in valves, heaters and drains of heaters. Management aspects as personnel selection and training, costs, and countable are also presented in this report. Owing to the high cost of man-hour of the members of the ININ staff, its participation in the refueling process was in smaller number than years before. (Author). 15. The occurrence of Fusarium toxins (zearalenone, DON, fumonisin, and T2) in some food commodities and feedstuffs in Syria Energy Technology Data Exchange (ETDEWEB) Ghanem, I; Al-Arfe, M [Atomic Energy Commission, Damascus (Syrian Arab Republic). Dept. of Molecular Biology and Biotechnology 2010-01-15 The presence of four Fusarium toxins (namely, zearalenone, Don, fuminosin, and T2) was studied in 129 food commodities and feedstuff samples using an enzyme-linked immunosorbent assay (ELISA). Results showed that the percentages of wheat samples contaminated with T2, fuminosin, Don and Zearalenone were : 33%, 31%, 11.6% and 12.5% for each toxin, respectively. Concentrations of these toxins in the contaminated samples fell in the range of 81 - 350, 330 - 1330, 270 - 420 and 42-67 {mu}g kg-1 for each toxin respectively. Barely samples showed higher percentages of contamination with those toxins amounting to 75.9%, 83.3%, 75% and 83.3% with concentrations ranging between 89-145, 270 - 1230, 650 - 3450 and 42-102 {mu}g kg-1 for T2, , fuminosin, Don and Zearalenone, respectively. Percentages of contaminated bran samples were 80% for T2 and 100% for each of fumonisin, Don and zearalenone. Concentrations of T2, fuminosin, Don and Zearalenone in bran samples ranged between 81-322 , 510 - 1670 , 280 - 750 and 42-81 {mu}g kg-1, respectively. All four tested toxins were present in corn samples. Levels of T2, , fuminosin, Don and Zearalenone in corn samples were in the range of 112-426 , 730 - 1820, 590 - 1080 and 63-112 {mu}g kg-1, respectively. Similarly, 100% of examined soya seed cake samples were found contaminated with various levels of the four assayed toxins, with levels of contamination ranging between 98-142 , 1340 - 2220 , 330 - 800 and 93-114 {mu}g kg-1, for T2, , fuminosin, Don and Zearalenone, respectively. All cotton seed cake samples were contaminated with the four tested toxins with contamination levels ranging between 94 - 142, 1120 - 1920, 280 - 1340 and 56 - 132 {mu}g kg-1 for T2, , fuminosin, Don and Zearalenone, respectively. Only 87% of the composite pelletted feed samples were contaminated with zearalenone, but all of theme were contaminated with various levels of the other three tested toxins. (author) 16. The occurrence of Fusarium toxins (zearalenone, DON, fumonisin, and T2) in some food commodities and feedstuffs in Syria International Nuclear Information System (INIS) Ghanem, I.; Al-Arfe, M. 2010-01-01 The presence of four Fusarium toxins (namely, zearalenone, Don, fuminosin, and T2) was studied in 129 food commodities and feedstuff samples using an enzyme-linked immunosorbent assay (ELISA). Results showed that the percentages of wheat samples contaminated with T2, fuminosin, Don and Zearalenone were : 33%, 31%, 11.6% and 12.5% for each toxin, respectively. Concentrations of these toxins in the contaminated samples fell in the range of 81 - 350, 330 - 1330, 270 - 420 and 42-67 μg kg-1 for each toxin respectively. Barely samples showed higher percentages of contamination with those toxins amounting to 75.9%, 83.3%, 75% and 83.3% with concentrations ranging between 89-145, 270 - 1230, 650 - 3450 and 42-102 μg kg-1 for T2, , fuminosin, Don and Zearalenone, respectively. Percentages of contaminated bran samples were 80% for T2 and 100% for each of fumonisin, Don and zearalenone. Concentrations of T2, fuminosin, Don and Zearalenone in bran samples ranged between 81-322 , 510 - 1670 , 280 - 750 and 42-81 μg kg-1, respectively. All four tested toxins were present in corn samples. Levels of T2, , fuminosin, Don and Zearalenone in corn samples were in the range of 112-426 , 730 - 1820, 590 - 1080 and 63-112 μg kg-1, respectively. Similarly, 100% of examined soya seed cake samples were found contaminated with various levels of the four assayed toxins, with levels of contamination ranging between 98-142 , 1340 - 2220 , 330 - 800 and 93-114 μg kg-1, for T2, , fuminosin, Don and Zearalenone, respectively. All cotton seed cake samples were contaminated with the four tested toxins with contamination levels ranging between 94 - 142, 1120 - 1920, 280 - 1340 and 56 - 132 μg kg-1 for T2, , fuminosin, Don and Zearalenone, respectively. Only 87% of the composite pelletted feed samples were contaminated with zearalenone, but all of theme were contaminated with various levels of the other three tested toxins. (author) 17. Site evaluation for U.S. Bureau of Mines experimental oil-shale mine, Piceance Creek basin, Rio Blanco County, Colorado Science.gov (United States) Ege, John R.; Leavesley, G.H.; Steele, G.S.; Weeks, J.B. 1978-01-01 The U.S. Geological Survey is cooperating with the U.S. Bureau of Mines in the selection of a site for a shaft and experimental mine to be constructed in the Piceance Creek basin, Rio Blanco County, Colo. The Piceance Creek basin, an asymmetric, northwest-trending large structural downwarp, is located approximately 40 km (25 mi) west of the town of Meeker in Rio Blanco County, Colo. The oil-shale, dawsonite, nahcolite, and halite deposits of the Piceance Creek basin occur in the lacustrine Green River Formation of Eocene age. In the basin the Green River Formation comprises three members. In ascending order, they are the Douglas Creek, the Garden Gulch, and the Parachute Creek Members, Four sites are presented for consideration and evaluated on geology and hydrology with respect to shale-oil economics. Evaluated criteria include: (1) stratigraphy, (2) size of site, (3) oil-shale yield, (4) representative quantities of the saline minerals dawsonite and nahcolite, which must be present with a minimum amount of halite, (5) thickness of a 'leached' saline zone, (6) geologic structure, (7) engineering characteristics of rock, (8) representative surface and ground-water conditions, with emphasis on waste disposal and dewatering, and (9) environmental considerations. Serious construction and support problems are anticipated in sinking a deep shaft in the Piceance Creek basin. The two major concerns will be dealing with incompetent rock and large inflow of saline ground water, particularly in the leached zone. Engineering support problems will include stabilizing and hardening the rock from which a certain amount of ground water has been removed. The relative suitability of the four potential oil-shale experimental shaft sites in the Piceance Creek basin has been considered on the basis of all available geologic, hydrologic, and engineering data; site 2 is preferred to sites 1, 3, and 4, The units in this report are presented in the form: metric (English). Both units of 18. Detection of and response to a probable volcanogenic T-wave event swarm on the western Blanco Transform Fault Zone Science.gov (United States) Dziak, R.P.; Fox, C.G.; Embley, R.W.; Lupton, J.E.; Johnson, G.C.; Chadwick, W.W.; Koski, R.A. 1996-01-01 The East Blanco Depression (EBD), a pull-apart basin within the western Blanco Transform Fault Zone (BTFZ), was the site of an intense earthquake T-wave swarm that began at 1317Z on January 9, 1994. Although tectonically generated earthquakes occur frequently along the BTFZ, this swarm was unusual in that it was preceded and accompanied by periodic, low-frequency, long-duration acoustic signals, that originated from near the swarm epicenters. These tremor-like signals were very similar in character to acoustic energy produced by a shallow-submarine eruption near Socorro Island, a seamount several hundred km west of Baja, California. The ???69 earthquakes and ???400 tremor-like events at the EBD occurred sporadically, with two periods of peak activity occurring between January 5-16 and 27-31. The swarm-like character of the earthquakes and the similarity of the tremor activity to the Socorro eruption indicated that the EBD was undergoing an intrusion or eruption episode. On January 27, six CTD/rosette casts were conducted at the site. Water samples from two of the stations yielded anomalous 3He concentrations, with maxima at ???2800 m depth over the main basin. In June 1994 two camera tows within the basin yielded evidence of pillow-lava volcanism and hydrothermal deposits, but no conclusive evidence of a recent seafloor eruption. In September 1994, deployments of the U.S. Navy's Advanced Tethered Vehicle resulted in the discovery of an active hydrothermal mound on the flanks of a pillow-lava volcano. The hydrothermal mound consists of Fe-rich hydrothermal precipitate and bacterial mats. Temperatures to 60??C were measured 30 cm below the surface. This is the first discovery of active hydrothermal vents along an oceanic fracture zone. Although no conclusive evidence of volcanic activity associated with the T-wave event swarm was found during these response efforts, the EBD has been the site of recent seafloor eruptions. Copyright 1996 by the American Geophysical 19. [Biotic and abiotic factors that affect the quality of Schinopsis balansae Engl. and Aspidosperma quebracho-blanco Schltdl. seeds]. Science.gov (United States) Alzugaray, Claudia; Carnevale, Nélida J; Salinas, Adriana R; Pioli, Rosanna 2007-06-01 Aspidosperma quebracho-blanco (white quebracho) and Schinopsis balansae (red quebracho) are distinctive trees of the South American Park in Argentina. Quebrachos are found in forests that have been exploited very intensively. The object of this work was the identification of biotic and abiotic factors specially fungal pathogen that affect the quality of both species and its relation with germination. Seeds where evaluated through germination test and the percentage of the incidence of fungal agents in two different years of harvest was determined. In S. balansae the germination rate was 77% and of 27% in 2000 and 2001 harvests, respectively. Associations fungi-germination were found in 2001 for Alternaria spp., Curvularia spp., and Fusarium spp., showing an coefficient of correlation = -0.84; -0.85 and -0.73 (p fruits. The incidence of pathogens was low and did not have association to germination. 20. Polymethoxylated flavones, flavanone glycosides, carotenoids, and antioxidants in different cultivation types of tangerines ( Citrus reticulata Blanco cv. Sainampueng) from Northern Thailand. Science.gov (United States) Stuetz, Wolfgang; Prapamontol, Tippawan; Hongsibsong, Surat; Biesalski, Hans-Konrad 2010-05-26 Polymethoxylated flavones (PMFs) and flavanone glycosides (FGs) were analyzed in hand-pressed juice and the peeled fruit of 'Sainampueng' tangerines ( Citrus reticulata Blanco cv. Sainampueng) grown in northern Thailand. The tangerines were collected from a citrus cluster of small orchard farmers and were cultivated as either agrochemical-based (AB), agrochemical-safe (AS), or organic grown fruits. Juice samples were also measured on contents of carotenoids, ascorbic acid, and tocopherols. The peel-deriving PMFs tangeretin, nobiletin, and sinensetin were found with high concentrations in juice as a result of simple squeezing, whereas amounts of those PMFs were negligibly low in peeled tangerine fruit. In contrast, the mean concentrations of the FGs narirutin, hesperidin, and didymin were several fold higher in peeled fruit than in tangerine juice and significantly higher in organic than AS and AB tangerines. Narirutin and hesperidin in juice from organic produces as well as narirutin in juice from AS produces were significantly higher than respective mean concentrations in juice from AB produces. beta-Cryptroxanthin was the predominant carotenoid beside zeaxanthin, lutein, lycopene, and beta-carotene in tangerine juice. Ascorbic acid concentrations were not predicted by the type of cultivation, whereas alpha-tocopherol was significantly higher in juice from organic than AS produces. In summary, hand-pressed juice of C. reticulata Blanco cv. Sainampueng serves as a rich source of PMFs, FGs, carotenoids, and antioxidants: 4-5 tangerine fruits ( approximately 80 g of each fruit) giving one glass of 200 mL hand-pressed juice would provide more than 5 mg of nobiletin and tangeretin and 36 mg of hesperidin, narirutin, and didymin, as well as 30 mg of ascorbic acid, >1 mg of provitamin A active beta-cryptoxanthin, and 200 microg of alpha-tocopherol. 1. [Don Quijote, a lucid mad]. Science.gov (United States) Alonso Fernández, Francisco 2004-01-01 The case of a 50-year-old hidalgo who believed to be transformed into a knight-errant named Don Quijote is a megalomaniac systematized delusion of transformation of the self, a delusion of metamorphosis in reference to the patient's own identity. The outward projection of this syndrome produces some delusional misidentifications of others, things and animals and include elements of a persecutory delusion which increase the grandiosity of the self. At the same time the hidalgo was maniac with a pathway of bipolar disorder. The phenomenon of donquijotismo is described as the defence of wasted causes and Sancho Panza as an illiterate Sócrates. 2. Plan de ecoturismo para la laguna de Solano (Guabizhún Directory of Open Access Journals (Sweden) Patricio Castro 2017-12-01 Full Text Available El desarrollo turístico de la laguna de Guabizhún y sus áreas de influencia se encuentra sustentado en el aprovechamiento sostenible de sus atractivos turísticos naturales y culturales, así como de los del entorno geográfico, mediante el diseño y la ejecución de programas para la gestión, la instalación de la planta turística adecuada y la infraestructura de apoyo al desarrollo del turismo de naturaleza, de acuerdo con los objetivos de sustentabilidad en sus dimensiones económica, ambiental y cultural del sitio y los conectores que forman las actividades turísticas y recreativas del área. Por ello, es importante destacar la participación de las comunidades en el desarrollo de la actividad turística, que pueden aportar como alternativa válida para mejorar las condiciones de vida local y ayudar indudablemente a la conservación de los ambientes naturales y, sobre todo, del patrimonio cultural de los pueblos, mediante una planificación y un control adecuados de los recursos, donde la actividad del ecoturismo puede llegar a constituir una fuente importante de ingresos. 3. Severe Accident Simulation of the Laguna Verde Nuclear Power Plant Directory of Open Access Journals (Sweden) Gilberto Espinosa-Paredes 2012-01-01 Full Text Available The loss-of-coolant accident (LOCA simulation in the boiling water reactor (BWR of Laguna Verde Nuclear Power Plant (LVNPP at 105% of rated power is analyzed in this work. The LVNPP model was developed using RELAP/SCDAPSIM code. The lack of cooling water after the LOCA gets to the LVNPP to melting of the core that exceeds the design basis of the nuclear power plant (NPP sufficiently to cause failure of structures, materials, and systems that are needed to ensure proper cooling of the reactor core by normal means. Faced with a severe accident, the first response is to maintain the reactor core cooling by any means available, but in order to carry out such an attempt is necessary to understand fully the progression of core damage, since such action has effects that may be decisive in accident progression. The simulation considers a LOCA in the recirculation loop of the reactor with and without cooling water injection. During the progression of core damage, we analyze the cooling water injection at different times and the results show that there are significant differences in the level of core damage and hydrogen production, among other variables analyzed such as maximum surface temperature, fission products released, and debris bed height. 4. Why I don't kill myself : [poems] / Paul-Eerik Rummo Index Scriptorium Estoniae Rummo, Paul-Eerik, 1942- 2003-01-01 Autori lühitutvustus lk. 262. Sisu: Why I don't kill myself ; The sky stoops over the earth ; Clinging ; Crooning. Orig.: Miks ma end ära ei tapa ; "Taevas on kummargil üle maa..." ; Kinni hoidmas ; Poolüminal 5. El día más blanco o el país de la memoria de Raúl Zurita Directory of Open Access Journals (Sweden) María Luisa Fischer 2014-06-01 Full Text Available Estudio la adscripción genérica de El día más blanco del poeta chileno Raúl Zurita, así como la significación de los epígrafes, otra forma de enmarcación del volumen. Entre la novela y la autobiografía, el libro se propone cubrir la grieta que existe entre la memoria personal y la memoria traumática del país. Describo la especial calidad visual de las imágenes del texto y su relación con las dificultades de construir una versión de la historia subjetiva y personal que se aúne a la historia del país, cuando ambas están quebradas. 6. Participation of the ININ in the activities of radioactive waste management of the Laguna Verde Central; Participacion del ININ en las actividades de gestion de desechos radiactivos de la Central Laguna Verde Energy Technology Data Exchange (ETDEWEB) Medrano L, M.; Rodriguez C, C.; Linares R, D. [ININ, Gerencia Subsede Sureste (Mexico); Ramirez G, R.; Zarate M, N. [Central Laguna Verde, CFE (Mexico)]. e-mail: [email protected] 2006-07-01 From the beginning of the operation of the Laguna Verde Central (CLV) the National Institute of Nuclear Research (ININ) has come supporting the CLV in the activities of administration of the humid and dry radioactive waste generated by the operation of the two units of the CLV, from the elaboration of procedures to the temporary storage in site, the implementation of a program of minimization and segregation of dry solid wastes, until the classification of the lots of humid waste and bulk dry wastes. In this work the description of the management activities of radioactive wastes carried out by the ININ in the facilities of the CLV to the date is presented, as well as some actions that they are had drifted in the future near, among those that it stands out the determination of the total alpha activity in humid samples by means of scintillation analysis. (Author) 7. De la risa a carcajadas al mal ejemplo quijotesco en la novela del XVIII. Don Quijote de la Manchuela Directory of Open Access Journals (Sweden) Agapita Jurado Santos 2013-03-01 Full Text Available Don Quixote rapidly became a huge success. It was translated into several languages and reworked into genres with a festive and theatrical nature. In Spain, during the seventeenth century, its comic side was exploited, which provoked liberating laughter that, in France, led to its association with the satire genre. In the eighteenth century, the novel was considered a minor genre, of no educational value. The century began with a fierce controversy over the meaning of Cervantes’ work, since according to Rapin, some readers would have seen a mockery of the Spanish nobility in the insane gentleman. However, during the eighteenth century the first steps were taken to reappraise Don Quixote due to its acceptance as a classic by the Spanish Royal Academy in 1780. The Academy considered Don Quixote a mocking and didactic hero, a bad example to be avoided. Yet, the work was an important step in the construction of a new genre, the novel. Don Quijote de la Manchuela, by Donato de Arenzana (1767, reflects an attentive reading of Cervantes’ Don Quixote, and special attention to the neoclassical cannon. Therefore it can provide useful information about writers’ interests, in the preromantic eighteenth century. 8. Estimation of seismic return periods in the Laguna Verde nuclear plant International Nuclear Information System (INIS) Flores R, J.H. 1992-01-01 The study of seismic risk in the area of the Laguna Verde Nucleo electric plant (PNLV) and its surroundings, one carries out estimating the different return periods and the occurrence probability in different intervals of time (5, 75, 100, 125, 150 years starting from the distribution of first type of Gumbel (G1) of extreme values (Burton, 1986), the value that was used to evaluate the useful life of the PNLV was of 50 years, the other periods will be occupy to evaluate 'temporal' nuclear cemeteries, that is to say for diminish the radioactive activity of the fuel assemblies already burned in the reactor pool or in a near place to the place. The seismic data that were used for the analysis were of the seismic catalog that it was elaborated from (1920-1982), around the place whose seismic half magnitude was of 5 grades Richter and a depth 65 km, these earthquakes are classified as shallow earthquakes, which are located in the continental plaque of North-America, these they are induced by the efforts of push of the plaque of Cocos, existing 36% of intermediate and 2 of deep earthquakes. (Author) 9. ???????????? ? ?????????? ??????? ??????? ?? ??????? ???????????? ? ?????? ???????-??-???? // Advantages and disadvantages of franchise business opportunities in Rostov-on-don OpenAIRE Bugayan, S.A.; Filimonenko, I. 2013-01-01 ? ?????? ??????????? ???????? ???????????? ? ?????????? ??????????? ??????? ?? ??????? ???????????? ? ?????? ???????-??-???? ?? ??????? ????????? ????, ????????????? ??????? ???? ????? ??????? ? ?? ?????????? ??????????? ????????. In this article are considered main cons and pros of franchise business opportunities in Rostov-on-Don, using different businesses as an example,efficiency of this type of business and its future possibilities. 10. "Don't know" responses to risk perception measures: implications for underserved populations. Science.gov (United States) Waters, Erika A; Hay, Jennifer L; Orom, Heather; Kiviniemi, Marc T; Drake, Bettina F 2013-02-01 Risk perceptions are legitimate targets for behavioral interventions because they can motivate medical decisions and health behaviors. However, some survey respondents may not know (or may not indicate) their risk perceptions. The scope of "don't know" (DK) responding is unknown. Examine the prevalence and correlates of responding DK to items assessing perceived risk of colorectal cancer. Two nationally representative, population-based, cross-sectional surveys (2005 National Health Interview Survey [NHIS]; 2005 Health Information National Trends Survey [HINTS]), and one primary care clinic-based survey comprised of individuals from low-income communities. Analyses included 31,202 (NHIS), 1,937 (HINTS), and 769 (clinic) individuals. Five items assessed perceived risk of colorectal cancer. Four of the items differed in format and/or response scale: comparative risk (NHIS, HINTS); absolute risk (HINTS, clinic), and "likelihood" and "chance" response scales (clinic). Only the clinic-based survey included an explicit DK response option. "Don't know" responding was 6.9% (NHIS), 7.5% (HINTS-comparative), and 8.7% (HINTS-absolute). "Don't know" responding was 49.1% and 69.3% for the "chance" and "likely" response options (clinic). Correlates of DK responding were characteristics generally associated with disparities (e.g., low education), but the pattern of results varied among samples, question formats, and response scales. The surveys were developed independently and employed different methodologies and items. Consequently, the results were not directly comparable. There may be multiple explanations for differences in the magnitude and characteristics of DK responding. "Don't know" responding is more prevalent in populations affected by health disparities. Either not assessing or not analyzing DK responses could further disenfranchise these populations and negatively affect the validity of research and the efficacy of interventions seeking to eliminate health disparities. 11. Don Quijote y los eruditos: Sobre una polémica crítica y sus implicaciones metacríticas OpenAIRE Pardo García, Pedro Javier 2000-01-01 [ES]Este trabajo trata sobre Don Quijote y los eruditos: una polémica crítica y sus implicaciones metacríticas. [EN]This paper deals with Don Quixote and scholars: a critical controversy and its implications metacritica. 12. 30 years in the Veracruz state coast landscape: Laguna Verde nuclear power station. 1. ed.; 30 anos de paisaje costero veracruzano: Central Nucleoelectrica Laguan Verde Energy Technology Data Exchange (ETDEWEB) Guevara, S; Moreno Casasola, P; Castillo Campos, G; Dorantes, C; Gonzalez Garcia, F; Halffter, G; Isunza, E; Lot H, A; Mendoza, R; Paradowska, K; Priego, A; Sanchez Vigil, C; Vazquez, G [Comision Federal de Electricidad and Instituto Nacional de Ecologia A.C. (Mexico) 2008-07-01 36 years ago one of the most important power projects of Mexico was born; the design and construction of the Nuclear power station Laguna Verde. This project became reality thanks to the commitment of a group of Mexican professionals that gave the best of them for its accomplishment. At that time, there was not in Mexico a legislation that contemplated the environmental protection; nevertheless, the Mexican Constitution anticipates that when in the country there is not legislation for the development of a project, this must adopt the legislation of the country that is selling it. In the specific case of Laguna Verde, the legislation of the United States of America was adopted and in the environmental part it had to issue the first Manifest of Environmental impact, that was called Informe Ambiental para la Contruccion de Laguna Verde en el Estado de Veracruz. This study was performed by several national as well as foreign institutions. Among the most outstanding are the Universidad Nacional Autonoma de Mexico, the Intituto Politecnico Nacional, the Universidad Veracruzana, the Intituto National para la Investigacion de Recursos Biologicos, the Instituto de Ecologia, A.C. With this report, the engineers undertook the task of designing and constructing, the biologists and ecologists to realize the studies to mitigate the effects caused to the environment during the construction and later, during the operation of the Nuclear power station. After 18 years of commercial operation of the power station the present book is completed, in which the results obtained in 1972, when the studies of the environmental report began are compared against the ones obtained throughout this period. It is important to see in the results of the different studies and indicators presented/displayed in this book, that the important changes on the environment are due, to the change of the ground use and the over-exploitation of the natural resources as it happens in almost all the country. The 13. Evaluación del postratamiento de aguas residuales municipales mediante la utilización de macrofitas como las lentejas de agua (lemma minor en lagunas de estabilización. Directory of Open Access Journals (Sweden) Juan Pablo Rodriguez Miranda 2018-04-01 Full Text Available El presente artículo, tiene el propósito de determinar la utilidad de la lenteja de agua (lemna minor como postratamiento en lagunas de estabilización que tratan aguas residuales domésticas, fue analizada una muestra de agua residual proveniente del efluente de la laguna anaerobia del sistema de tratamiento de aguas residuales el Salguero de Valledupar-Cesar; la muestra fue inoculada con las lentejas de agua, las cuales fueron tomadas de reservorios ubicados en las afueras del Municipio en mención. Se realizó el montaje empleando un sistema tipo batch a escala laboratorio con tres replicas y dos controles los parámetros analizados fueron nutrientes (nitrógeno y fósforo. La remoción de nutrientes fue: 72% P y 95% N. Se pudo establecer que las lentejas de agua presentan una buena eficiencia en relación a la remoción de nutrientes. 14. ["Is it an animal inside? "Melanie Klein's unpublished Don Juan Paper (1939)]. Science.gov (United States) Frank, Claudia 2008-01-01 Klein had been asked to contribute an article to the birthday number of the International Journal for Jones. The author outlines how she hurriedly wrote a text about Don Juan which, however, was rejected by the editor. Essential parts of it are presented in German translation. The manuscript is discussed in the context of Klein's published work as well as of the relevant contemporary literature. In Klein's view, Don Juan's genitality is determined by oral impulses and fears. By his manic acting out he attempts to ward off a depressive break-down. The paper ends with some reflections about why Klein--ontrary to her intention--failed to revise her manuscript for later publication. 15. National autonomous university of Mexico RELAP/SCDAPSIM-based plant simulation and training applications to the Laguna Verde NPP International Nuclear Information System (INIS) Chavez-Mercado, C.; Hohorst, J.K.; Allison, C.M. 2004-01-01 The RELAP/SCDAPSIM code, designed to predict the behavior of reactor systems during normal and accident conditions, is being developed by Innovative Systems Software as part of the International SCDAP Development and Training Program (SDTP). This code is being used as the simulator engine for the National Autonomous University of Mexico's Simulation and Training Facility located at the Campus Morelos in Jiutepec, Mexico. This paper describes the RELAP/SCDAPSIM code, the Simulation and Training facility at the National Autonomous University of Mexico, and the application of the training system to the Laguna Verde Nuclear Power Plant located in the Mexican state of Veracruz. (author) 16. Adrenalectomy for Cushing's syndrome: do's and don'ts. Science.gov (United States) Paduraru, D N; Nica, A; Carsote, M; Valea, A 2016-01-01 Aim. To present specific aspects of adrenalectomy for Cushing's syndrome (CS) by introducing well established aspects ("do's") and less known aspects ("don'ts"). Material and Method. This is a narrative review. Results. The "do's" for laparoscopic adrenalectomy (LA) are the following: it represents the "gold standard" for secretor and non-secretor adrenal tumors and the first line therapy for CS with an improvement of cardio-metabolic co-morbidities; the success rate depending on the adequate patients' selection and the surgeon's skills. The "don'ts" are large (>6-8 centimeters), locally invasive, malignant tumors requiring open adrenalectomy (OA). Robotic adrenalectomy is a new alternative for LA, with similar safety and conversion rate and lower pain drugs use. The "don'ts" are the following: lack of randomized controlled studies including oncologic outcome, different availability at surgical centers. Related to the sub-types of CS, the "do's" are the following: adrenal adenomas which are cured by LA, while adrenocortical carcinoma (ACC) requires adrenalectomy as first line therapy and adjuvant mitotane therapy; synchronous bilateral adrenalectomy (SBA) is useful for Cushing's disease (only cases refractory to pituitary targeted therapy), for ectopic Cushing's syndrome (cases with unknown or inoperable primary site), and for bilateral cortisol producing adenomas. The less established aspects are the following: criteria of skilled surgeon to approach ACC; the timing of surgery in subclinical CS; the need for adrenal vein catheterization (which is not available in many centers) to avoid unnecessary SBA. Conclusion. Adrenalectomy for CS is a dynamic domain; LA overstepped the former OA area. The future will improve the knowledge related to RA while the cutting edge is represented by a specific frame of intervention in SCS, children and pregnant women. Abbreviations: ACC = adrenocortical carcinoma, ACTH = Adrenocorticotropic Hormone, CD = Cushing's disease, CS 17. FRONTERAS DIFUSAS Y ACTORES SOCIALES MESTIZOS: DEBATES CONCEPTUALES Y DESARROLLOS ANALÍTICOS EN TORNO A LOS ESPACIOS DE FRONTERA Y SUS VINCULACIONES CON LOS INDIOS-BLANCOS EN LA REGIÓN DEL CHACO DURANTE LA SEGUNDA MITAD DEL SIGLO XIX Directory of Open Access Journals (Sweden) Julio César Spota 2010-12-01 Full Text Available En la frontera establecida entre el Estado argentino y las distintas parcialidades aborígenes de la región del Chaco durante la segunda parte del siglo XIX, se configuraron identidades étnicas mestizas que escapaban a la simple esquematización de blancos e indios, civilizados y salvajes. La praxis histórica de los actores sociales como los indios-blancos (soldados desertores, criminales fugitivos de la ley, perseguidos y refugiados políticos y comerciantes que fueron incorporados dentro de los grupos indígenas proporciona un espacio privilegiado de reflexión antropológica poco explorado hasta el momento. En el presente artículo nos proponemos determinar las causas históricas que motivaron la migración de los criollos y recuperar la perspectiva de los actores sociales que protagonizaron los hechos estudiados. 18. Cervantes, Lizardi, and the Literary Construction of The Mexican Rogue in Don Catrín de la fachenda Directory of Open Access Journals (Sweden) Vilches Patricia 2017-12-01 Full Text Available This study explores the socio-economic legacies and critique of nation-building found in the work of Jose Joaquin Fernandez de Lizardi (1776-1827. In the nineteenth century, the Latin American elite struggled to disassociate itself from a suffocating colonial machine; they sought their own identity, and writing became a way to express their frustration. As in other parts of Latin America, Mexican intellectuals protested fossilisation via Cervantes’s Don Quijote. Using the Spanish author’s text as a blueprint, Lizardi’s Don Catrín de la fachenda depicted a turbulent society that was in the process of abandoning a decaying colonial order. Don Quijote’s characters engaged in power struggles and were involved in a variety of forms of social antagonism. Lizardi juxtaposed and superimposed these on an American geographical and socio-economic space where there was much dissension around the nation’s direction. The social and economic rules of Mexico (and Latin America today can be said to be already present in the social exchanges in Don Catrín. It was in this context that Don Quijote was “Mexicanised” by Lizardi and thereby made to participate in local reflections on liberty, patriotism, capitalism, and citizenship. Cervantes’s text thus took on a socio-political meaning in the narrative of Latin America’s past and present. 19. La parodia como marco estructural en Don Quijote y Los viajes de Gulliver Directory of Open Access Journals (Sweden) Alfonso Muñoz Corcuera 2016-07-01 Full Text Available Los viajes de Gulliver, de Jonathan Swift, es una de las obras más conocidas de la literatura universal. Sin embargo, su recepción actual, al menos en España, se produce sobre todo por medio de adaptaciones en las que no se puede apreciar el calado de la obra literaria original. En este estudio se pretende profundizar en el análisis de Los viajes de Gulliver a través de una comparación con Don Quijote, enfocándose en los recursos paródicos: mientras Don Quijote parodia los libros de caballerías, Los viajes de Gulliver parodia los libros de viajes. El principal objetivo de esta comparación no será tanto demostrar una influencia de la obra de Cervantes sobre la de Swift, sino, más bien, iluminar algunos aspectos de Los viajes de Gulliver. Gulliver´s Travels, of Jonathan Swift, is one of the most well-known works in world literature. However, its actual reception, at least in Spain, it´s produced mostly through adaptations in which it´s impossible to appreciate the profundity of the original literary work. In this article, I intend to dig deeply into the analysis of Gulliver´s Travels through a comparison with Don Quixote, focusing on the parodic resources: while Don Quixote parodies the books of chivalry, Gulliver´s Travels parodies travel books. The main goal of this comparison will not be to prove some influence of Cervantes´ work in Swift´s work, but to illuminate some aspects of Gulliver´s Travels. 20. Rho GTPasas como blancos terapéuticos relevantes en cáncer y otras enfermedades humanas Directory of Open Access Journals (Sweden) Pablo Lorenzano Menna 2010-12-01 Full Text Available Las Rho GTPasas son una familia de proteínas clave en la transmisión de señales provenientes del exterior celular hacia efectores intracelulares tanto citoplasmáticos como nucleares. En los últimos año ha habido un desarrollo vertiginoso de múltiples herramientas genéticas y farmacológicas, lo que ha permitido establecer de manera mucho más precisa las funciones específicas de estas proteínas. El objetivo de la presente revisión es hacer foco en las múltiples funciones celulares reguladas por las Rho GTPasas, describiendo en detalle el mecanismo molecular involucrado. Se discute además la participación de estas proteínas en diversas enfermedades humanas haciendo énfasis en su vinculación con el cáncer. Por último, se hace una actualización detallada sobre las estrategias terapéuticas en experimentación que tienen a las Rho GTPasas como blancos moleculares. 1. To report the obtained results in the simulation with the FCS-11 and Presto codes of the two first operation cycles of the Laguna Verde Unit 1 reactor International Nuclear Information System (INIS) Montes T, J.L.; Moran L, J.M.; Cortes C, C.C. 1990-08-01 The objective of this work is to establish a preliminary methodology to carry out analysis of recharges for the reactor of the Laguna Verde U-1, by means of the evaluation of the state of the reactor core in its first two operation cycles using the FCS2 and Presto-B codes. (Author) 2. Hubungan antara Aktivitas Fisik Terhadap Memori Kerja Murid SMA Don Bosco III Bekasi Directory of Open Access Journals (Sweden) Michelle Clarissa Junaidi 2017-03-01 Full Text Available Latar belakang. Memori kerja merupakan bagian dari memori jangka pendek yang berperan penting dalam membantu proses pembelajaran dan dipengaruhi oleh aktivitas fisik, memori kerja yang rendah akan menimbulkan kesulitan untuk menerima informasi baru serta penurunan prestasi belajar. Tujuan. Mengetahui pengaruh aktivitas fisik terhadap kapasitas memori kerja murid SMA Don Bosco III. Metode. Penelitian metode analitik dengan pendekatan potong lintang pada 113 murid SMA Don Bosco III, Bekasi, pada 18 – 20 Juli 2016. Penelitian dilakukan dengan menggunakan kuesioner demografi, kuesioner skrining gangguan mental dan penyakit kronis, Physical Acitivity Questionnaire of Adolescent (PAQ-A dan Operation Span (O-SPAN. Analisis data dengan univariat dan bivariat menggunakan uji korelasi Spearman. Hasil. Terdapat 113 murid SMA Don Bosco III dengan kisaran usia 14 – 17 tahun, usia terbanyak 15 tahun (47.8%, laki-laki 61,1%, murid kelas X 44.2%. Mayoritas responden memiliki aktivitas fisik “kurang baik” dan rerata memori kerja 6,16. Analisis Spearman menunjukkan terdapat hubungan bermakna (p<0,05 antara aktivitas fisik terhadap memori kerja dengan korelasi positif lemah (r=0,384. Kesimpulan. Terdapat korelasi positif antara aktivitas fisik dan memori kerja, aktivitas fisik yang semakin tinggi cenderung akan meningkatkan memori kerja. 3. L’utilité de la théorie du don The utility of gift theory Utilidad de la teoría del don Directory of Open Access Journals (Sweden) Norbert Alter 2012-12-01 Full Text Available Norbert Alter explique l’utilité et l’actualité de la théorie de Marcel Mauss pour penser la coopération en entreprise et l’engagement au travail. Il revient sur ses qualités heuristiques et sa portée critique nécessaires à mobiliser pour donner des clefs de compréhension et d’action au monde du travail. À cette contribution répond celle d’Alain Caillé, « Le paradigme du don face aux nouvelles réalités du monde du travail. Quelques remarques »Norbert Alter explains here the utility and topicality of Marcel Mauss’ theory in an analysis touching both on cooperation within a business structure and on people’s commitment to work. He reviews the heuristic qualities and critical scope that must be mobilised to create ways of understanding and acting within the work world. Alain Caillé responds to this contribution with his own article entitled, “ The gift paradigm facing new realities in the work world. Comments” (Le paradigme du don face aux nouvelles réalités du monde du travail. Quelques remarques.Norbert Alter explica la utilidad y la actualidad de la teoría de Marcel Mauss para pensar la cooperación en la empresa y el compromiso en el trabajo. Desde una nueva perspectiva, aborda las cualidades heurísticas de esa teoría y su alcance crítico, que es necesario movilizar para contar con claves de comprensión y de acción en el mundo laboral. A su contribución, Alain Caillé responde con el artículo “El paradigma del don frente a las nuevas realidades del mundo laboral. Algunas observaciones”. 4. Don't pay taxes, save your money! OpenAIRE Bradáč, Michal 2011-01-01 Bachelor thesis "Don't Pay Taxes, Save Your Money!" focuses on the impact of the existence of tax havens on private and public sector. On the theoretical level, it shows the attractivity of tax havens for sufficiently large firms that can afford to pay costs of tax planning and profit manipulations. On the empirical level, it shows that tax havens are really the most successful jurisdictions in attracting foreign investors. In the end, two models of tax competition are introduced in order to ... 5. Identification of protoplast-isolation responsive microRNAs in Citrus reticulata Blanco by high-throughput sequencing. Science.gov (United States) Xu, Xiaoyong; Xu, Xiaoling; Zhou, Yipeng; Zeng, Shaohua; Kong, Weiwen 2017-01-01 Protoplast isolation is a stress-inducing process, during which a variety of physiological and molecular alterations take place. Such stress response affects the expression of totipotency of cultured protoplasts. MicroRNAs (miRNAs) play important roles in plant growth, development and stress responses. However, the underlying mechanism of miRNAs involved in the protoplast totipotency remains unclear. In this study, high-throughput sequencing technology was used to sequence two populations of small RNA from calli and callus-derived protoplasts in Citrus reticulata Blanco. A total of 67 known miRNAs from 35 families and 277 novel miRNAs were identified. Among these miRNAs, 18 known miRNAs and 64 novel miRNAs were identified by differentially expressed miRNAs (DEMs) analysis. The expression patterns of the eight DEMs were verified by qRT-PCR. Target prediction showed most targets of the miRNAs were transcription factors. The expression levels of half targets showed a negative correlation to those of the miRNAs. Furthermore, the physiological analysis showed high levels of antioxidant activities in isolated protoplasts. In short, our results indicated that miRNAs may play important roles in protoplast-isolation response. 6. ESTABILIZACIÓN DEL PIGMENTO AZUL ULTRAMAR EN CEMENTO PÓRTLAND BLANCO Directory of Open Access Journals (Sweden) JUAN GUILLERMO MORALES RENDÓN 2008-01-01 Full Text Available Se prepararon muestras de cemento azul a partir de cemento Pórtland Blanco Tipo III, según Normas Técnicas Colombianas NTC y pigmento Azul Ultramar U-601 adicionado en un 2% en peso del cemento. El cemento se caracterizó químicamente por fluorescencia de rayos X, y físicamente mediante los ensayos típicos según las NTC. Al pigmento y al cemento se les determinaron sus coordenadas cromáticas por espectrofotometría mediante el sistema CIELAB. Se eligieron varios aditivos y adiciones (entre orgánicos, inorgánicos y minerales para ser adicionados al cemento azul en diferentes dosificaciones en peso. Tanto a las muestras de cemento azul sin aditivo como a aquellas con las diferentes dosificaciones de aditivos, se les determinaron sus características físicas de desempeño y coordenadas cromáticas a diferentes edades de curado en agua saturada con cal (1, 3, 7 y 28 días. Adicionalmente se les determinó el color en las mismas edades a especimenes curados a las condiciones ambientales del laboratorio. Se presentó decoloración total en todos aquellos cementos adicionados con aditivos orgánicos, y decoloración parcial en los cementos adicionados con algunos de los aditivos inorgánicos y ciertas adiciones minerales. Tanto los tiempos de fraguado, como las resistencias a la compresión y demás variables de desempeño experimentaron cambios significativos, en algunos casos positivos y en otros negativos, como consecuencia y efecto de las diferentes dosificaciones utilizadas de cada uno de los aditivos. 7. Hábitos alimenticios y migratorios del tiburón blanco Carcharodon carcharias (Lamniformes: Lamnidae de Isla Guadalupe inferidos por el análisis de isótopos estables de δ15N and δ13C Directory of Open Access Journals (Sweden) Mario Jaime-Rivera 2014-08-01 Full Text Available La composición isotópica de los tejidos de los depredadores tope en el ambiente marino provee información sobre su ecología trófica y su comportamiento migratorio. Estudios previos han mostrado que el tejido dérmico puede registrar patrones largos de movimiento y caza. El objetivo de este estudio fue describir los hábitos tróficos y migratorios de los tiburones blancos de Isla Guadalupe realizando un análisis de isótopos estables de su tejido dérmico. Consideramos un pequeño grupo de muchos posibles taxa que los tiburones pudieron haber comido a lo largo de su migración: pinípedos, calamares y atunes. Estas presas fueron agrupadas en cinco áreas focales: Golfo de California, Isla Guadalupe, Costa de California, SOFA y Hawái. Realizamos un modelo de mezcla bayesiano para estudiar la ecología trófica de este depredador tope. Los promedios del valor isotópico de la dermis del tiburón blanco fueron δ13C (-14.5‰ y δ15N (19.1‰. Los promedios del valor isotópico de la dermis transformada para semejar músculo fueron δ13C (-16.6 ‰ y δ15N (21.2‰. El modelo de mezcla mostró una probable depredación de los tiburones en áreas oceánicas como el SOFA y confirmó la importancia de los pinnípedos como presa principal del tiburón blanco en Isla Guadalupe. 8. Abundancia y estructura poblacional de Crocodylus acutus (Reptilia: Crocodylidae en la laguna Palmasola, Oaxaca, México Directory of Open Access Journals (Sweden) Jesús García-Grajales 2014-03-01 Full Text Available La abundancia y estructura poblacional son pará-metros importantes para evaluar y comparar el estatus de conservación de una población a través del tiempo en un área determinada. Este estudio describe la abundancia y estructura poblacional de Crocodylus acutus en la laguna Palmasola, Oaxaca. El trabajo consistió en recorridos nocturnos, entre las 21 y 24h, durante la fase de luna nueva para contabilizar el número de individuos y obtener estimaciones poblacionales. El tamaño poblacional estimado fluctuó de 32.7 a 93 individuos según el modelo utilizado. Las tasas de encuentro registradas fluctuaron de 32 a 109.3 ind/km lineal durante los 40 recorridos efectuados con un tiempo promedio de navegación de 18 minutos. Existió una marcada dominancia de la clase III (subadultos, seguido por la clase II y en menor proporción las clases IV y V, así como aquellos individuos en los que no se pudo determinar el tamaño corporal, en ambas épocas del año. Mientras tanto, los individuos juveniles (Clase II se observaron en mayor proporción asociados al manglar que cubre las orillas del cuerpo de agua (26.1%, los individuos subadultos (Clase III a menudo se observaron sobre el espejo de agua sin vegetación flotante (22.7% y entre el manglar que cubre las orillas del cuerpo de agua (15.7%, mientras que los ejemplares adultos se observaron con mayor frecuencia sobre el espejo de agua sin vegetación flotante (9.7%. Con la presente información se contribuye al conocimiento de la ecología poblacional de C. acutus en la laguna Palmasola donde el tamaño poblacional estimado parece mostrar valores altos con respecto a lo reportado en otros estados de la República Mexicana. 9. Don Quijote, doña Rodríguez y los duques Directory of Open Access Journals (Sweden) Stanislav Zimic 1997-12-01 Full Text Available Al llegar Don Quijote al palacio de los duques y "viéndose tratar del mesmo modo que él había leído se trataban Ios tales caballeros en Ios pasados siglos ... , aquél fue el primer día que de todo en todo conoció y creyó ser caballero andante verdadero y no fantastíco" (1378. Comprensiblemente, esta afirmacion ha causado gran perplejidad entre los lectores de todas las épocas: "Luego, antes ¿no lo había creído?" . La cuestión se complica mucho más, poco después de estos eufóricos momentos, al confesar Don Quijote a la duquesa: "Dios sabe si hay Dulcinea o no en el mundo, o si es fantástica ono es fantástica ... 10. Validation of a new version of software for monitoring the core of nuclear power plant of Laguna Verde Unit 2, at the end of Cycle 10; Validacion de una nueva version del software para monitoreo del nucleo de la Central Laguna Verde Unidad 2, al final del Ciclo 10 Energy Technology Data Exchange (ETDEWEB) Hernandez, G.; Calleros, G.; Mata, F. [Comision Federal de Electricidad, Central Nucleoelectrica de Laguna Verde, Carretera Cardel-Nautla Km 42.5, Veracruz (Mexico)], e-mail: [email protected] 2009-10-15 This work shows the differences observed in thermal limits established in the technical specifications of operation, among the new software, installed at the end of Cycle 10 of Unit 2 of nuclear power plant of Laguna Verde, and the old software that was installed from the beginning of the cycle. The methodology allowed to validate the new software during the coast down stage, before finishing the cycle, for what could be used as tool during the shutdown of Unit 2 at the end of Cycle 10. (Author) 11. Experiments in rooting bishop pine (Pinus muricata D. Don) cuttings Science.gov (United States) Constance I. Millar 1987-01-01 Presented here are results of rooting studies using hedges established from juvenile seedlings of "blue" and "green" foliaged bishop pine (Pinus muricata D. Don) from Mendocino and Sonoma Counties, California. Rootability, averaged over all clones and all setting dates, was 88%. The average time for 50% of the... 12. Development of an interactive model of the Laguna Verde nuclear power plant based on the RELAP/SCDAP code International Nuclear Information System (INIS) Salazar C, J.H.; Ramos P, J.C.; Salazar S, E.; Chavez M, C. 2003-01-01 The present work describes the development of an interactive model of the Nuclear power plant of Laguna Verde (CNLV) based on the RELAP/SCDAP nuclear code, and it incorporation to a classroom simulator. The functional prototype it allows to make evaluations for operational transients and postulates accidents, with capacitation purposes, training, analysis and design. It emphasizes on the methodology used to establish the inter activity. Such methodology, is based on a modular structure in the one that multiple processes can be executed in an independent way and where the generated information is stored in segments of shared memory (characteristic that allows the UNIX operating system) and sent to the different processes by means of communication routines developed in C programming language. The utility of the system is demonstrated by means of the use of interactive display graphics (mimic diagrams, pictorials and tendency graphics) for the simultaneous dynamic visualization of the variables more significant that involve to the pattern of a transitory event type (for example failure of the controller of feeding water in a BWR reactor). Near with the interactive module, it was developed a model of the reactor of the CNLV for the code of better estimation RELAP/SCDAP. Finally the evaluation of the model is described, where it is interpreted in general form the behavior of those main variables that describe the stationary state, corroborating that follow the same tendency that those reported in the FSAR (Final Safety Analysis Report) of the Laguna Verde plant. The obtained results allow to conclude that the made development was satisfactory and that it presents enormous advantages regarding the capacity and time of analysis when using tools of visualization in real time of execution. (Author) 13. Registros de zopilote rey (Sarcoramphus papa en el área de Laguna de Términos, Campeche, México Directory of Open Access Journals (Sweden) Mircea Hidalgo-Mihart 2012-07-01 Full Text Available Reportamos la presencia de dos individuos juveniles de zopilote rey, Sarcoramphus papa, en la Selva La Montaña localizada al suroeste del Área de Protección de Flora y Fauna Silvestre Laguna de Términos, Campeche, México. Realizamos el registro por medio de fotografías utilizando cámaras trampa. La presencia de esta especie protegida en el área evidencia la importancia que tiene la región de la Selva La Montaña para la conservación de la biodiversidad, especialmente para especies en peligro de extinción. 14. Registros de zopilote rey (Sarcoramphus papa) en el área de Laguna de Términos, Campeche, México OpenAIRE Mircea Hidalgo-Mihart; Fernando M. Contreras-Moreno; Luz A. Pérez-Solano 2012-01-01 Reportamos la presencia de dos individuos juveniles de zopilote rey, Sarcoramphus papa, en la Selva La Montaña localizada al suroeste del Área de Protección de Flora y Fauna Silvestre Laguna de Términos, Campeche, México. Realizamos el registro por medio de fotografías utilizando cámaras trampa. La presencia de esta especie protegida en el área evidencia la importancia que tiene la región de la Selva La Montaña para la conservación de la biodiversidad, especialmente para especies en peligro d... 15. Epidemiología de la enfermedad de Chagas en el municipio Andrés Eloy Blanco, Lara, Venezuela: infestación triatomínica y seroprevalencia en humanos OpenAIRE Rodríguez-Bonfante,Claudina; Amaro,Aned; García,María; Mejías Wohlert,Ligia Elena; Guillen,Pamela; Antonio García,Rafael; Álvarez,Naysan; Díaz,Marialejandra; Cárdenas,Elsys; Castillo,Silvia; Bonfante-Garrido,Rafael; Bonfante-Cabarcas,Rafael 2007-01-01 Se realizó un despistaje serológico y recolección de vectores en cuatro comunidades rurales del municipio Andrés Eloy Blanco, Estado Lara, Venezuela. La muestra fue escogida en forma sistemática y aleatoria basada en conglomerados familiares. Se muestrearon 869 habitantes para determinar anticuerpos anti-Trypanosoma cruzi y anti-Leishmania sp. por inmunofluorescencia indirecta, aceptando como positivo diluciones > a 1:32 para anticuerpos anti-T. cruzi no reactivos para antígenos de Leishmania... 16. Fallugia paradoxa (D. Don) Endl. ex Torr.: Apache-plume Science.gov (United States) Susan E. Meyer 2008-01-01 The genus Fallugia contains a single species - Apache-plume, F. paradoxa (D. Don) Endl. ex Torr. - found throughout the southwestern United States and northern Mexico. It occurs mostly on coarse soils on benches and especially along washes and canyons in both warm and cool desert shrub communities and up into the pinyon-juniper vegetation type. It is a sprawling, much-... 17. Don Bates: the medical historian as educator, activist, and historian of science. Science.gov (United States) Weisz, George 2009-01-01 The author outlines the academic and extra-academic career of Don Bates as a physician-historian, political activist, and creator of the interdisciplinary Department of Social Studies of Medicine at McGill University. 18. The LAGUNA design study-towards giant liquid based underground detectors for neutrino physics and astrophysics and proton decay searches CERN Document Server Angus, D; Autiero, D.; Apostu, A.; Badertscher, A.; Bennet, T.; Bertola, G.; Bertola, P.F.; Besida, O.; Bettini, A.; Booth, C.; Borne, J.L.; Brancus, I.; Bujakowsky, W.; Campagne, J.E.; Danil, G.Cata; Chipesiu, F.; Chorowski, M.; Cripps, J.; Curioni, A.; Davidson, S.; Declais, Y.; Drost, U.; Duliu, O.; Dumarchez, J.; Enqvist, T.; Ereditato, A.; von Feilitzsch, F.; Fynbo, H.; Gamble, T.; Galvanin, G.; Gendotti, A.; Gizicki, W.; Goger-Neff, M.; Grasslin, U.; Gurney, D.; Hakala, M.; Hannestad, S.; Haworth, M.; Horikawa, S.; Jipa, A.; Juget, F.; Kalliokoski, T.; Katsanevas, S.; Keen, M.; Kisiel, J.; Kreslo, I.; Kudryastev, V.; Kuusiniemi, P.; Labarga, L.; Lachenmaier, T.; Lanfranchi, J.C.; Lazanu, I.; Lewke, T.; Loo, K.; Lightfoot, P.; Lindner, M.; Longhin, A.; Maalampi, J.; Marafini, M.; Marchionni, A.; Margineanu, R.M.; Markiewicz, A.; Marrodan-Undagoita, T.; Marteau, J.E.; Matikainen, R.; Meindl, Q.; Messina, M.; Mietelski, J.W.; Mitrica, B.; Mordasini, A.; Mosca, L.; Moser, U.; Nuijten, G.; Oberauer, L.; Oprina, A.; Paling, S.; Pascoli, S.; Patzak, T.; Pectu, M.; Pilecki, Z.; Piquemal, F.; Potzel, W.; Pytel, W.; Raczynski, M.; Rafflet, G.; Ristaino, G.; Robinson, M.; Rogers, R.; Roinisto, J.; Romana, M.; Rondio, E.; Rossi, B.; Rubbia, A.; Sadecki, Z.; Saenz, C.; Saftoiu, A.; Salmelainen, J.; Sima, O.; Slizowski, J.; Slizowski, K.; Sobczyk, J.; Spooner, N.; Stoica, S.; Suhonen, J.; Sulej, R.; Szarska, M.; Szeglowski, T.; Temussi, M.; Thompson, J.; Thompson, L.; Trzaska, W.H.; Tippmann, M.; Tonazzo, A.; Urbanczyk, K.; Vasseur, G.; Williams, A.; Winter, J.; Wojutszewska, K.; Wurm, M.; Zalewska, A.; Zampaolo, M.; Zito, M. 2010-01-01 The feasibility of a next generation neutrino observatory in Europe is being considered within the LAGUNA design study. To accommodate giant neutrino detectors and shield them from cosmic rays, a new very large underground infrastructure is required. Seven potential candidate sites in different parts of Europe and at several distances from CERN are being studied: Boulby (UK), Canfranc (Spain), Fr\\'ejus (France/Italy), Pyh\\"asalmi (Finland), Polkowice-Sieroszowice (Poland), Slanic (Romania) and Umbria (Italy). The design study aims at the comprehensive and coordinated technical assessment of each site, at a coherent cost estimation, and at a prioritization of the sites within the summer 2010. 19. Analysis of the documents about the core envelopment of nuclear reactor at the Laguna Verde U-1 power plant International Nuclear Information System (INIS) Zamora R, L.; Medina F, A. 1999-01-01 The degradation of internal components at BWR type reactors is an important subject to consider in the performance availability of the power plant. The Wuergassen nuclear reactor license was confiscated due to the presence of cracking in the core envelopment. In consequence it is necessary carrying out a detailed study with the purpose to avoid these problems in the future. This report presents a review and analysis of documents and technical information referring to the core envelopment of a BWR/5/6 and the Laguna Verde Unit 1 nuclear reactor in Mexico. In this document are presented design data, documents about fabrication processes, and manufacturing of core envelopment. (Author) 20. Multiplicación in vitro de segmentos nodales del clon de ñame Blanco de Guinea (Dioscorea cayenensis - D. rotundata ) en sistemas de cultivo semiautomatizado OpenAIRE Manuel Cabrera Jova; Rafael Gómez Kosky; Sergio Rodríguez Morales; Jorge López Torres; Aymé Rayas Cabrera; Milagros Basail Pérez; Arletys Santos Pino; Víctor Medero Vega; Germán Rodríguez Rodríguez 2009-01-01 Con el empleo del sistema de inmersión temporal fue posible incrementar la multiplicación in vitro de los segmentos nodales en el clon de ñame Blanco de Guinea. Con este tipo de sistema de cultivo se obtuvieron los más altos valores para la altura de la planta, número de entrenudos por planta, así como para la masa fresca y seca de las mismas. Las condiciones de cultivo creadas en el sistema de inmersión temporal para la multiplicación in vitro de los segmentos nodales lograron el más alto co... 1. La denuncia a través de la mujer: La casa de la laguna, de Rosario Ferré Directory of Open Access Journals (Sweden) Ana Molestina 2015-08-01 Full Text Available La historia puertorriqueña es una historia de imposiciones identitarias, choques culturales y ambivalencia desde la llegada de los españoles a la isla. En La casa de la laguna, Ferré analiza el pasado y el presente de Puerto Rico. Crea una reconstrucción simbolizada en la historia de las familias Mendizábal-Monfort, en la cual Isabel Monfort, trata de descubrir las causas del fracaso de su matrimonio. En esta búsqueda y reflexión personal, se representan las versiones olvidadas o silenciadas de la historia puertorriqueña y de igual manera, da voz y vida a las mujeres marginadas o silenciadas. 2. We don't need another hero. Science.gov (United States) Badaracco, J L 2001-09-01 Everybody loves the stories of heroes like Martin Luther King, Jr., Mother Teresa, and Gandhi. But the heroic model of moral leadership usually doesn't work in the corporate world. Modesty and restraint are largely responsible for the achievements of the most effective moral leaders in business. The author, a specialist in business ethics, says the quiet leaders he has studied follow four basic rules in meeting ethical challenges and making decisions. The rules constitute an important resource for executives who want to encourage the development of such leaders among their middle managers. The first rule is "Put things off till tomorrow." The passage of time allows turbulent waters to calm and lets leaders' moral instincts emerge. "Pick your battles" means that quiet leaders don't waste political capital on fights they can't win; they save it for occasions when they really want to fight. "Bend the rules, don't break them" sounds easier than it is--bending the rules in order to resolve a complicated situation requires imagination, discipline, restraint, flexibility, and entrepreneurship. The fourth rule, "Find a compromise," reflects the author's finding that quiet leaders try not to see situations as polarized tests of ethical principles. These individuals work hard to craft compromises that are "good enough"--responsible and workable enough--to satisfy themselves, their companies, and their customers. The vast majority of difficult problems are solved through the consistent striving of people working far from the limelight. Their quiet approach to leadership doesn't inspire, thrill, or provide story lines for uplifting TV shows. But the unglamorous efforts of quiet leaders make a tremendous difference every day in the corporate world. 3. Las lagunas estratigráficas y las superficies negativas en arqueología Directory of Open Access Journals (Sweden) Murillo Fragero, José I. 2004-12-01 Full Text Available Owing much to geological research, archaeological stratigraphy and its tools and principles are developed through continuous experiences following a model of critical study and reflection. In this case, we have attempted to approach the issue of stratigraphic gaps, a concept that includes various processes (hiatuses, erosional gaps and that we have identified through negative surfaces. Their definition and documentation is often vital in archaeological analysis and historical archaeology.La estratigrafía arqueológica, deudora de la investigación geológica, templa sus herramientas y desarrolla sus principios gracias a las continuas experiencias llevadas a cabo de acuerdo a un modelo de trabajo y reflexión crítico. En este caso, hemos pretendido un acercamiento al tema de las lagunas estratigráficas, concepto que encierra distintos procesos (hiatos, vacíos erosionales y que identificamos gracias a las superficies negativas. Su definición y documentación es, a menudo, clave en el análisis arqueológico de la arquitectura histórica. 4. A comparative study of long-baseline superbeams within LAGUNA for large\\theta_{13}$CERN Document Server Coloma, Pilar; Pascoli, Silvia 2012-01-01 The Daya Bay and RENO experiments have recently observed a non-zero$\\theta_{13}$at more than$5\\sigma$CL. This has important consequences for future neutrino oscillation experiments. We analyze these within the LAGUNA design study which considers seven possible locations for a European neutrino observatory for proton decay, neutrino, and astroparticle physics. The megaton-scale detector would be an ideal target for a CERN-based neutrino beam with baselines ranging from 130 km to 2300 km. We perform a detailed study to assess the physics reach of the three detector options - a 440 kton water \\v{C}erenkov, a 100 kton liquid argon and a 50 kton liquid scintillator detector - at each of the possible locations, taking into account the recent measurement of$\\theta_{13}$. We study the impact of the beam properties and detector performances on the sensitivity to CP-violation and the mass hierarchy. We find that a liquid argon or water \\v{C}erenkov detector can make a$3\\sigma$discovery of CP violation for$60%-7...
5. Reproduction of the flow-power map of the Laguna Verde power plant
International Nuclear Information System (INIS)
Amador G, R.; Gonzalez M, V.M.
1993-01-01
The National Commission of Nuclear Safety and Safeguards (CNSNS) requires to have calculation tools which allows it to make analysis independent of the behavior of the reactor core of Laguna Verde nuclear power plant (CNLV) with the purpose to support the evaluation and discharge activities of the fuel recharges licensing. The software package Fms (Fuel Management System) allows to carry out an analysis of the core of the BWR type reactors along the operation cycle to detect possible anomalies and/or helping in the fuel management. In this work it is reproduced the flow-power for the CNLV using the Presto code of the Fms software package. The comparison of results with the map used by the operators of CNLV shows good agreement between them. Another exercise carried out was the changes study that the axial and radial power outlines undergo as well as the thermohydraulic parameters (LHGR, APLHGR, CPR) when moving a control rod. The obtained results show that is had the experience to effect analysis of the reactor behavior using the Presto-Fms code therefore the study of the rest of the software package for the obtention of nuclear parameters used in this code is recommended. (Author)
6. Estimating floodplain sedimentation in the Laguna de Santa Rosa, Sonoma County, CA
Science.gov (United States)
Curtis, Jennifer A.; Flint, Lorraine E.; Hupp, Cliff R.
2013-01-01
We present a conceptual and analytical framework for predicting the spatial distribution of floodplain sedimentation for the Laguna de Santa Rosa, Sonoma County, CA. We assess the role of the floodplain as a sink for fine-grained sediment and investigate concerns regarding the potential loss of flood storage capacity due to historic sedimentation. We characterized the spatial distribution of sedimentation during a post-flood survey and developed a spatially distributed sediment deposition potential map that highlights zones of floodplain sedimentation. The sediment deposition potential map, built using raster files that describe the spatial distribution of relevant hydrologic and landscape variables, was calibrated using 2 years of measured overbank sedimentation data and verified using longer-term rates determined using dendrochronology. The calibrated floodplain deposition potential relation was used to estimate an average annual floodplain sedimentation rate (3.6 mm/year) for the ~11 km2 floodplain. This study documents the development of a conceptual model of overbank sedimentation, describes a methodology to estimate the potential for various parts of a floodplain complex to accumulate sediment over time, and provides estimates of short and long-term overbank sedimentation rates that can be used for ecosystem management and prioritization of restoration activities.
7. Economic analysis of extended cycles in the Laguna Verde nuclear power plant
International Nuclear Information System (INIS)
Hernandez N, H.; Hernandez M, J.L.; Francois L, J.L.
2004-01-01
The present work presents a preliminary analysis of economic type of extended cycles of operation of the Unit One in the Laguna Verde nuclear power plant. It is analysed an equilibrium cycle of 18 months firstly, with base to the Plan of Use of Energy of the Federal Commission of Electricity, being evaluated the cost of the energy until the end of the useful life of the plant. Later on an alternative recharge scenario is presented with base to an equilibrium cycle of 24 months, implemented to the beginning of the cycle 11, without considering transition cycles. It is added in both cycles the cost of the substitution energy, considering the unitary cost of the fuel of a dual thermoelectric power station of 350 M We and evaluating in each operation cycle, in both scenarios, the value of the substitution energy. The results show that a reduction of the days of recharge in the cycle of 24 months could make this option but favorable economically. The duration of the period of recharge rebounds in considerable grade in the cost of energy generation for concept of fuel. (Author)
8. Estimation of requirements of eolic energy equivalent to the electric generation of the Laguna Verde nuclear power plant; Estimacion de requerimientos de energia eolica equivalente a la generacion electrica de la Central Nucleoelectrica de Laguna Verde
Energy Technology Data Exchange (ETDEWEB)
Garcia V, M.A.; Hernandez M, I.A. [Facultad de Ingenieria, Division de Ingenieria Electrica, UNAM, 04510 Mexico D.F. (Mexico)]. E-mail: [email protected]; Martin del Campo M, C. [Facultad de Ingenieria, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, UNAM, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Morelos (Mexico)
2004-07-01
The advantages are presented that have the nuclear and eolic energy as for their low environmental impact and to the human health. An exercise is presented in the one that is supposed that the electric power generated by the Laguna Verde Nuclear Power plant (CNLV), with capacity of 1365 M W, it should be produced by eolic energy when in the years 2020 and 2025 the units 1 and 2 of the CNLV reach its useful life and be moved away. It is calculated the number of aero generators that would produce the electric power average yearly of the CNLV, that which is equal to install eolic parks with capacity of 2758 M W, without considering that it will also be invested in systems of back generation to produce electricity when the aero generators stops for lack of wind. (Author)
9. Deoxynivalenol (DON) is toxic to human colonic, lung and monocytic cell lines, but does not increase the IgE response in a mouse model for allergy
International Nuclear Information System (INIS)
Instanes, Christine; Hetland, Geir
2004-01-01
We examined whether the common crop mycotoxin deoxynivalenol (DON) from Fusarium species is toxic to human colonic (Caco-2), lung (A549) and monocytic (U937) cell lines. Moreover, since DON reportedly induces increased levels of Th2 cytokines and total IgE, and we have observed that mould extracts adjuvated allergy development in mice, possible adjuvant effect of DON on allergy was studied in a mouse model. For all the cells, exposure to DON for 24 h reduced cellular protein synthesis, proliferation and survival rate dose-dependently. In addition, production of IL-8 in the U937 cell line increased up to eight-fold at levels of DON just lower than the most toxic one, suggesting that IL-8 can be used as an additional index for cytotoxicity in mononuclear phagocytes. However, DON did not increase levels of allergen-specific IgE or IgG1 in the mouse model for allergy. These results suggest that DON, when inhaled or ingested, may have toxic effect on human alveolar macrophages and epithelial cells in lungs and colon, but does not increase the allergic response to allergens
10. Aplicação de ácido giberélico (GA3 em précolheita de tangerina ‘Poncã’ (Citrus reticulata blanco = Application of Gibberelic acid (GA3 on preharvest of ‘Ponkan’ mandarin (Citrus reticulata Blanco fruit
Directory of Open Access Journals (Sweden)
Júnior Cesar Modesto
2006-01-01
11. Questions to the reactors power upgrade of the Nuclear Power Plant of Laguna Verde; Cuestionamientos al aumento de potencia de los reactores de la Central Nuclear de Laguna Verde
Energy Technology Data Exchange (ETDEWEB)
Salas M, B., E-mail: [email protected] [UNAM, Facultad de Ciencias, Departamento de Fisica, Circuito exterior s/n, Ciudad Universitaria, 04510 Mexico D. F. (Mexico)
2014-08-15
The two reactors of the Nuclear Power Plant of Laguna Verde (NPP-L V) were subjected to power upgrade labors with the purpose of achieving 20% upgrade on the original power; these labors concluded in August 24, 2010 for the Reactor 1 and in January 16, 2011 for the Reactor 2, however in January of 2014, the NNP-L V has not received by part of the Comision Nacional de Seguridad Nuclear y Salvaguardias (CNSNS) the new Operation License to be able to work with the new power, because it does not fulfill all the necessary requirements of safety. In this work is presented and analyzed the information obtained in this respect, with data provided by the Instituto Federal de Acceso a la Informacion Publica y Proteccion de Datos (IFAI) and the Comision Federal de Electricidad (CFE) in Mexico, as well as the opinion of some workers of the NPP-L V. The Governing Board of the CFE announcement that will give special continuation to the behavior on the operation and reliability of the NPP-L V, because the frequency of not announced interruptions was increased 7 times more in the last three years. (Author)
12. Effects of temperature and time on deoxynivalenol (DON and zearalenone (ZON content in corn
Directory of Open Access Journals (Sweden)
Jauković Marko
2014-01-01
Full Text Available Fumonisins are Fusarium mycotoxins that occur in corn and corn-based foods and they have been implicated in several animal and human diseases. Their effect on human health is unclear, however, fumonisins are considered to be risk factors for cancer. Baking, frying, and extrusion cooking of corn at high temperatures (190°C reduce fumonisin concentrations in foods, with the amount of reduction achieved depending on cooking time, temperature, recipe, and other factors. The aim of this work was to evaluate the effectiveness of temperature (200 and 220 °C and time (15 and 20 min on the detoxification of corn flour deliberately contaminated with DON and ZON. After processing at 200°C for 15 min, an average of 12% and after 20 min an average of 15% of DON was lost. At 200°C ZON content was reduced by 22% (after 15 min and by 27% (after 20 min. Higher temperature (220°C did not significantly affect further reduction of DON or ZON content. The process was only partially effective in both cases. [Projekat Ministarstva nauke Republike Srbije, br. TR-31023 i br. TR-31053
13. Applications of the monitor of loose parts in the cycle 6 of the Laguna Verde Unit 2 power plant; Aplicaciones del monitor de partes sueltas en el ciclo 6 de la Unidad 2 de la central Laguna Verde
Energy Technology Data Exchange (ETDEWEB)
Calleros, G.; Mendez, A.; Gomez, R.A. [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Veracruz (Mexico); Castillo, R.; Bravo, J.M. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)]. E-mail: [email protected]
2004-07-01
The monitor of loose parts (Loose Parts Monitoring System) installed in the Unit 2 of the Laguna Verde Central is a tool to detect strange objects or parts loose in the system of refrigeration of the reactor that could be impacted in the walls of the recirculation knots or in the internal of the reactor. In this work two applications are shown carried out with the Monitor of Loose Parts, determining the characteristics of the stable nominal conditions, those which when changing, they are used to diagnose during the Cycle 6 of the Unit 2, failures in the components of the the recirculation circuits or to identify mechanical vibrations of the recirculation knots induced by a flow of recirculation bistable associated to operative conditions of the reactor. (Author)
14. Don't make me think: a common sense approach to Web usability
National Research Council Canada - National Science Library
Krug, Steve
2006-01-01
.... To ensure that your sites provide that experience, this guide from usability guru Krug distills his years of on-the-job experience into a practical primer on the do's and don'ts of good Web design...
15. What We Don't Understand, We Explain to Each Other
Science.gov (United States)
Pines, David
2015-01-01
"What we don't understand, we explain to each other" was Robert Oppenheimer's 1948 description of theoretical physics as a profession. Because the phrase connects research, teaching, and learning, it seemed the right approach for the talk I gave to the AAPT [American Association of Physics Teachers] on receiving the 2013 J.D. Jackson…
16. 'Don't play the butter notes': jazz in medical education.
Science.gov (United States)
Bradner, Melissa; Harper, Darryl V; Ryan, Mark H; Vanderbilt, Allison A
2016-01-01
Jazz has influenced world music and culture globally - attesting to its universal truths of surviving, enduring, and triumphing over tragedy. This begs the question, what can we glean in medical education from this philosophy of jazz mentoring? Despite our training to understand disease and illness in branching logic diagrams, the human experience of illness is still best understood when told as a story. Stories like music have tempos, pauses, and silences. Often they are not linear but wrap around the past, future, and back to the present, frustrating the novice and the experienced clinician in documenting the history of present illness. The first mentoring lesson Hancock discusses is from a time he felt stuck with his playing - his sound was routine. Miles Davis told him in a low husky murmur, 'Don't play the butter notes'. In medical education, 'don't play the butter notes' suggests not undervaluing the metacognition and reflective aspects of medical training that need to be fostered during the early years of clinical teaching years.
17. Calidad de vida en el trabajo: Profesionales de la salud de Clínica Río Blanco y Centro de Especialidades Médicas Quality of life at work: Health Professionals Clinica Rio Blanco and Center Especialidades Médicas
Directory of Open Access Journals (Sweden)
2012-09-01
18. Application of new control technology during the maintenance of equipment in the Laguna Verde nuclear power plant
International Nuclear Information System (INIS)
Ojeda R, M. A.
2008-01-01
In the nuclear power plant of Laguna Verde, in normal operation and recharges are carried out activities of preventive maintenance and corrective to different equipment, due to the one displacement of radioactive materials from the vessel of the reactor until the one system of vapor, different radiation levels are generated (from low until very high) in the circuits of vapor and water, the particles can be incrusted on those interior surfaces of the pipes and equipment, creating this way a potential risk of contamination and exhibition during the maintenance of equipment. To help to optimize the dose to the personnel the use of new technology the has been implemented which besides contributing an absolute control of the work, it offers bigger comfort to the one worker during the development of their work, also contributing a supervision more effective of the same one. Using the captured and processed information of the work developed you can use for the personnel's capacitation and feedback of the work for the continuous improvement of the same one. During a reduction of programmed power and normal operation are carried out maintenance correctives and specific works to preserve the readiness and ability of the equipment and with this to maintain the security of the nuclear power plant. The development of the theme it is showing the advances and commitments of personnel to take to excellence to the nuclear power plant of Laguna Verde showing to the obtained results of the dose and benefits of 2 works carried out in the nuclear power plant where tools ALARA were applied as well as the use of the new technology (Video Equipment of Tele dosimetry and Audio 'VETA') in works carried out in the building of purification level 10.15, change and cuts of filter of the prefilters of system G16, as well as,the retirement and transfer for its decay of High Integrity Container (HIC) of the building of purification level -0.55 to the Temporary Warehouse in Site. Works of high
19. The first theatrical adaptations of the Don Quixote and the beginning of Cervantes
Directory of Open Access Journals (Sweden)
Carmen Rivero Iglesias
2012-12-01
Full Text Available The present study analyzes the first appearances of Don Quixote on German stages. The goal is to illustrate how these theatrical performances determine the reception of Cervantes’ work in 17th century Germany. The first performances in Heidelberg (1613 and Dessau (1614 display an interpretation of Don Quixote, which intensifies the grotesque dimension of Cervantes’ original. Its satire is transformed into a satire of Spain in a context determined by political and religious animosity between Catholics and Protestants. The first German translation inherited this conception of Cervantes’ work. This conception would acquire new shades until middle of the 18th century, when the alteration of historical coordinates and the rise of individuality and genius thoroughly transformed its interpretation.
20. Gender differences in national assessment of educational progress science items: What does i don't know really mean?
Science.gov (United States)
Linn, Marcia C.; de Benedictis, Tina; Delucchi, Kevin; Harris, Abigail; Stage, Elizabeth
The National Assessment of Educational Progress Science Assessment has consistently revealed small gender differences on science content items but not on science inquiry items. This assessment differs from others in that respondents can choose I don't know rather than guessing. This paper examines explanations for the gender differences including (a) differential prior instruction, (b) differential response to uncertainty and use of the I don't know response, (c) differential response to figurally presented items, and (d) different attitudes towards science. Of these possible explanations, the first two received support. Females are more likely to use the I don't know response, especially for items with physical science content or masculine themes such as football. To ameliorate this situation we need more effective science instruction and more gender-neutral assessment items.
1. Variación anual de la biomasa de Nymphoides fallax Ornduff (Menyanthaceae en la Laguna de Tecocomulco, Hidalgo, México
Directory of Open Access Journals (Sweden)
Agustin Quiroz-Flores
2015-07-01
Full Text Available Durante un ciclo anual se cuantificó la variación en la estratifi cación vertical de la biomasa deNymphoides fallaxy se analizaron las variables físicas y químicas del agua y sedimentos de la laguna de Tecocomulco, Hidalgo. La producción anual neta de N. fallax fue de 3 070.1 g PS m2. En el mes de junio la biomasa alcanzó su máximo (958.4 g PS m2 . La contribución de biomasa foliar de N. fallax a la proporción total de biomasa representa el 10%, la de peciolos alcanza el 40% y la contribución de biomasa subterránea equivale en ocasiones a más del 50%. El nivel de fósforo en los sedimentos se encuentra por arriba de la cantidad necesaria para sostener la producción vegetal (= 0.04%. Por los resultados obtenidos en este estudio, se puede señalar que en aquellas zonas ribereñas de la laguna en donde los agricultores han construido bordos, se propicia que durante la época de lluvias la columna de agua cambie bruscamente sus dimensiones pasando de 10 cm hasta alcanzar los 75 cm de profundidad y se eleven los niveles de fósforo en agua y sedimentos, lo que a su vez induce queNymphoides fallaxse vea estresada, y en un caso extremo, temporalmente sea sustituida por aquellas especies mejor adaptadas a las nuevas condiciones físicas y químicas del medio.
2. Cambios en el régimen hídrico de la laguna Lasuntay y Chuspicocha por variaciones en el Nevado Huaytapallana
OpenAIRE
Jacinto Arroyo Aliaga; Pedro Gurmendi Párraga
2011-01-01
Objetivos: Estimar los efectos de las variaciones de torrentes de agua de los glaciares del Nevado Huaytapallana que emanan al sistema hídrico de las lagunas de Lasuntay y Chuspicocha. Métodos: Se utilizó el método general teórico deductivo de nivel explicativo, con un diseño no experimental del tipo transversal en el tratamiento de información; como método específico se ha utilizado el balance de masa del glaciar para el cálculo de volúmenes de agua de los torrentes a partir de la instalació...
3. Validation of a new software version for monitoring of the core of the Unit 2 of the Laguna Verde power plant with ARTS
International Nuclear Information System (INIS)
Calleros, G.; Riestra, M.; Ibanez, C.; Lopez, X.; Vargas, A.; Mendez, A.; Gomez, R.
2005-01-01
In this work it is intended a methodology to validate a new version of the software used for monitoring the reactor core, which requires of the evaluation of the thermal limits settled down in the Operation Technical Specifications, for the Unit 2 of Laguna Verde with ARTS (improvements to the APRMs, Rod Block Monitor and Technical specifications). According to the proposed methodology, those are shown differences found in the thermal limits determined with the new versions and previous of the core monitoring software. Author)
4. El Dioscórides de Andrés Laguna en los textos de Cervantes: de la materia medicinal al universo literario
OpenAIRE
Francisco López-Muñoz; Cecilio Álamo
2007-01-01
The literary works of Miguel de Cervantes have been widely studied from numerous points of view, including the medical one. In the present work, we defend the hypothesis that the Andrés Laguna version of Dioscorides was the source used by Cervantes in his literary passages related to therapeutic aspects, especially in relation to plants with medicinal properties. This book, a copy of which was in Cervantes’ private library, is the only medical treatise cited by the novelist in any of his writ...
5. Valoración económica de los servicios ecosistémicos de una Laguna del sudeste bonaerense (Argentina
Directory of Open Access Journals (Sweden)
Agustina Iwan
2017-01-01
Full Text Available La valoración de servicios ecosistémicos es un tema ampliamente debatido y en constante producción. En Argentina existe poca evidencia empírica de aplicación de metodologías tendientes a dar valor econó- mico a los beneficios asociados a ecosistemas específicos. Este trabajo explica la situación ambiental de una laguna endorreica en el sudeste de la provincia de Buenos Aires y la valoración económica de algunos servicios ecosistémicos asociados a ella. La Laguna de Los Padres es un humedal de importancia local debido a los servicios ecosistémicos que proporciona y como espacio recreativo de valor simbólico sociocultural para la población. La modelización por su carácter sintético y capacidad explicativa, permitió caracterizar el sistema y la selección de cuatro servicios ecosistémicos (SE posibles de ser valorados física y crematísticamente considerando la disponibilidad de información. Los mimos son: el abastecimiento de agua, el secuestro de CO2 , el control de la erosión y el valor de existencia de la biodiversidad. La valoración económica casi siempre infra o subvalora el ambiente; no obstante, puede ser un instrumento político útil para la toma de decisiones de planificación y gestión ambiental en general porque lleva la discusión al terreno monetario. La sumatoria de los servicios ambientales permitió aproximar un Valor Económico Total (VET equivalente al 4,6% del presupuesto anual 2014 del Partido de Gral. Pueyrredón con una superficie de 1.453,44 km2 , y 619.000 habitantes (Instituto de Estadísticas y Censos [INDEC], 2010.
6. Analysis of the effects of Zimbabwean white farmers on small scale farming in Nigeria Análisis de los efectos de la presencia de agricultores blancos de Zimbabwe en la agricultura a pequeña escala en Nigeria
Directory of Open Access Journals (Sweden)
2013-05-01
7. Coleópteros acuáticos de lagunas situadas en el noroeste de la provincia de Corrientes, Argentina
Directory of Open Access Journals (Sweden)
María C. GOMEZ LUTZ
2012-01-01
Full Text Available El objetivo de este estudio es contribuir al conocimiento de la biodiversidad de coleópteros acuáticos del NE argentino. Los sitios de muestreo corresponden a dos lagunas permanentes ubicadas en el departamento Capital de la provincia de Corrientes, Argentina. Los muestreos fueron realizados desde octubre de 2010 a marzo de 2011. En total, 107 especies de coleópteros, incluidas en 40 géneros y ocho familias fueron registradas: Haliplidae, Dytiscidae, Noteridae, Dryopidae, Hydrochidae, Hydrophilidae, Limnichidae y Scirtidae. La especie Berosus hamatus Knisch es un nuevo registro para la Argentina. Dos familias (Haliplidae y Dryopidae, cuatro géneros (Haliplus Latreille; Pelonomus Erichson, Onopelmus Spangler, Phaenonotum Sharp y 14 especies son citados por primera vez para la provincia de Corrientes.
8. IMPACTO DE LOS EVENTOS DE SEQUÍA EN LA REGIÓN DE LA CUENCA HIDROGRÁFICA DE LA LAGUNA SAUCE GRANDE (PROVINCIA DE BUENOS AIRES, ARGENTINA
Directory of Open Access Journals (Sweden)
María E. Carbone
2015-01-01
Full Text Available La distribución e intensidad de los extremos hídricos provoca un impacto directo sobre las actividades humanas. Las características particulares de los eventos secos y húmedos ocurridos en la región de la cuenca hidrográfica de la laguna Sauce Grande, durante el período 1971- 2010, se analizan mediante la aplicación del Índice de severidad de sequía de Palmer. El 49% de los casos analizados correspondieron a sequías débiles, e incipientes. Los valores más extremos de eventos secos (-4.31 ocasionaron daños irreparables en los rendimientos de granos, que disminuyeron un 19% respecto al promedio actual. Durante los meses estivales se observaron los casos secos severos y extremos (12%. Se identificaron los períodos secos que mayor injerencia tuvieron sobre la producción agrícola ganadera de la región, sucedidas durante los años 2008 y 2009, la relación existente entre los valores de los índices severos y extremos en la morfometría de la laguna y estuario del río Sauce Grande.
9. Climate variability during the deglaciation and Holocene in a high-altitude alpine lake deduced from the sedimentary record from Laguna Seca, Sierra Nevada, southern Iberian Peninsula
Science.gov (United States)
Camuera, Jon; Jiménez-Moreno, Gonzalo; José Ramos-Román, María; García-Alix, Antonio; Jiménez-Espejo, Francisco; Anderson, R. Scott
2017-04-01
High-resolution X-ray fluorescence (XRF), magnetic susceptibility (MS), color and lithological analyses have been carried out on a 3.6 m-long sediment core from Laguna Seca, a high-elevation dry lake from Sierra Nevada mountain range, southern Spain. This is the longest sedimentary record retrieved from an alpine lake in southern Iberian Peninsula. Besides, alpine lakes are very sensitive environments to climate changes and previous studies showed that Laguna Seca could provide an excellent record to identify millennial-scale climate variations during deglaciation and the whole Holocene. XRF analyses, in particular high calcium and low K/Ca ratios, show aridity phases, very well represented during Last Glacial Maximum (LGM) and the Younger Dryas (YD). Arid events are also shown at ca. 8.1 ka BP, ca. 4.4 ka BP and the latest Holocene. On the other hand, negative values in calcium and positive values in K/Ca appear in the Bølling-Allerød (BA) and during the early Holocene until ca. 6 ka BP, indicating more humidity and higher run-off. A progressive aridification trend is also observed in the Holocene, changing from more humid conditions during the early Holocene to more aridity during the late Holocene.
10. Evaluation of the integrity and duration of the Laguna Verde nuclear power plant life- Plant Life Management program (PLIM). TC MEX 04/53 Technical Cooperation Project
International Nuclear Information System (INIS)
Arganis J, C.R.; Diaz S, A.; Aguilar T, J.A.
2006-01-01
As part of the IAEA TC MEX 04/53 Project 'Evaluation of the integrity and extension of life of the Laguna Verde nuclear power plant Handling Program of plant' whose objective is the one of beginning the actions to apply the methodology of Handling of plant life in the Unit 1 of the Laguna Verde Nucleo electric Central for to obtain the Renovation of License in 2020 the ININ, through the Department of Synthesis and Characterization of materials has carried out more of 20 analysis of susceptibility to the intergranular cracking for corrosion under effort in interns so much of the reactor of the unit 1 like of the unit 2 documenting the current state of components based on the type or types of materials that conform them, to it thermomechanical history, operational and of production, as well as of the particularities associated to its use and operation. For the application of the methodology of life handling of plant 5 structure systems or pilot components were selected, to carry out the programs of handling of the aging and handling of plant life: The encircling of the reactor core (Core Shroud), the reactor pressure vessel (Reactor Pressure Vessel), the primary container (Primary Containment), the recirculation system of feeding water (Reactor Feed Water) and cables. (Author)
11. Comunidades de insectos acuáticos de charcos temporarios y lagunas en la ciudad de Buenos Aires (Argentina Aquatic insect communities of temporary pools and permanent ponds in Buenos Aires City (Argentina
Directory of Open Access Journals (Sweden)
María S. Fontanarrosa
2004-12-01
Full Text Available Se realizó un estudio comparativo de la comunidad de insectos acuáticos presente en charcos temporarios de parques y plazas de la ciudad de Buenos Aires, y en lagunas permanentes de la Reserva Ecológica Costanera Sur, situada en la ribera del Río de la Plata. Se revisaron 3436 charcos y se visitaron, en 149 oportunidades, seis lagunas de la reserva. Para el conjunto de ambientes, se registraron 85 taxones pertenecientes a cinco órdenes de insectos. Los coleópteros fueron los más diversos (36 taxones, seguidos por los dípteros (27, heterópteros (17, odonatos (4 y efemerópteros (1. Se observaron altos valores de riqueza en los charcos temporarios (58 taxones y las lagunas sin vegetación flotante (64 taxones. La diversidad estimada de los charcos temporarios fue significativamente (pWe studied the community of aquatic insects inhabiting both temporary pools and permanent ponds occuring in Buenos Aires City. A total of 3436 rain pools were examined, and six permanent ponds at the "Reserva Ecológica Costanera Sur" in the Río de la Plata riverside were visited 149 times. A total of 85 taxa were recorded from both habitats, included in five orders of Insecta. The order Coleoptera showed the highest diversity values (36 taxa, followed by Diptera (27, Heteroptera (17, Odonata (4, and Ephemeroptera (1. High values of richness were observed in temporary pools (58 taxa and permanent ponds without floating vegetation (64 taxa. The diversity index for temporary ponds was significantly (p<0,05 lower than in permanent habitats.
12. Libros adquiridos por don Pedro Fermín de Vargas en sus viajes por las Antillas
Directory of Open Access Journals (Sweden)
Sergio Elías Ortíz
1962-04-01
Full Text Available Entre los papeles relacionados con la vida de Don Pedro Fermín de Vargas, que pueden consultarse en el Archivo General de Indias de Sevilla, hay una carta de él y una lista de libros que envía al Administrador de Correos de la Habana, Don José Fuertes, antiguo amigo suyo, luego su corresponsal y a la vez espía de sus pasos para aprisionarlo, con el objeto de que se los guardase “en algún rincón de sus casa”.
13. Gino Germani y la historia de la sociología en Argentina. Entrevista al sociólogo Alejandro Blanco
Directory of Open Access Journals (Sweden)
Jaime Eduardo Jaramillo Jiménez
2011-07-01
Full Text Available En la entrevista realizada a Alejandro Blanco, quien ha venido trabajando en una sociología y una historia de la sociología en América Latina, y particularmente en Argentina, se exploran, en un primer momento, algunas sincronías en el proceso de institucionalización de la sociología, en Argentina y Colombia, así como en otros países de la región. Posteriormente, la entrevista se enfoca en el papel y la figura de Gino Germani en la fundación de la Carrera de Sociología en la Universidad de Buenos Aires, ubicándolo en las discusiones y trayectoria del campo intelectual de su época. Por último, el entrevistado alude a los años sesenta en la sociología argentina, explorando el papel de algunas revistas e instituciones, nacionales e internacionales, en sus procesos de inicial consolidación y legitimación.
14. Report on the Fourth Reactor Refueling. Laguna Verde Nuclear Central. Unit 1. April-May 1995
International Nuclear Information System (INIS)
Mendoza L, A.; Flores C, E.; Lopez G, C.P.F.
1995-01-01
The fourth refueling of the Unit 1 of Laguna Verde Nuclear Central was executed in the period of April 17 to May 31 of 1995 with the participation of a task group of 358 persons, included technicians and radiation protection officials and auxiliaries.The radiation monitoring and radiological surveillance to the workers was present length ways the refueling process and always attached to the ALARA criteria. The check points for radiation levels were set at: primary container or dry well, reloading floor, decontamination room (level 10.5), turbine building and radioactive waste building. To take advantage of the refueling process, rooms 203 and 213 of the turbine buildings were subject to inspection and maintenance work in valves, heaters and drains of heaters. Management aspects as personnel selection and training, costs, and countable are also presented in this report. Owing to the high cost of man-hour of the members of the ININ staff, its participation in the refueling process was in smaller number than years before. (Author)
15. Investigation of chikungunya fever outbreak in Laguna, Philippines, 2012
Directory of Open Access Journals (Sweden)
Julius Erving Ballera
2015-12-01
Full Text Available Background: In July 2012, the Philippines National Epidemiology Center received a report of a suspected chikungunya fever outbreak in San Pablo City, Laguna Province, the first chikungunya cases reported from the city since surveillance started in 2007. We conducted an outbreak investigation to identify risk factors associated with chikungunya. Methods: A case was defined as any resident of Concepcion Village in San Pablo City who had fever of at least two days duration and either joint pains or rash between 23 June and 6 August 2012. Cases were ascertained by conducting house-to-house canvassing and medical records review. An unmatched case-control study was conducted and analysed using a multivariate logistic regression. An environmental investigation was conducted by observing water and sanitation practices, and 100 households were surveyed to determine House and Breteau Indices. Human serum samples were collected for confirmation for chikungunya IgM through enzyme-linked immunosorbent assay. Results: There were 98 cases identified. Multivariate analysis revealed that having a chikungunya case in the household (adjusted odds ratio [aOR]: 6.2; 95% confidence interval [CI]: 3.0–12.9 and disposing of garbage haphazardly (aOR: 2.7; 95% CI: 1.4–5.4 were associated with illness. House and Breteau Indices were 27% and 28%, respectively. Fifty-eight of 84 (69% serum samples were positive for chikungunya IgM. Conclusion: It was not surprising that having a chikungunya case in a household was associated with illness in this outbreak. However, haphazard garbage disposal is not an established risk factor for the disease, although this could be linked to increased breeding sites for mosquitoes.
16. Origen y distribución de pesticidas organoclorados (OCPs) en sedimentos actuales de la Laguna de El Hito (Cuenca, España Central)
OpenAIRE
Sánchez Palencia, Yolanda; Ortiz, José Eugenio; Torres, Trinidad de
2015-01-01
Se llevó a cabo el estudio del estado ambiental actual de la Laguna de El Hito basado en el análisis y cuantificación de 24 pesticidas organoclorados (OCPs): hexaclorobenceno, hexaclorociclohexanos, diclorodifenil-tricloroetano sus homólogos y metabolitos (DDTs), y ciclodienos (aldrín, dieldrín, endrín, endrín aldehido, endrín cetona, α- clordano, γ-clordano, endosulfán I, endosulfán II, endosulfán sulfato, heptacloro, heptacloro epóxido B y metoxicloro). Algunos compuestos ...
17. The E-learning Cabaret: do's and don'ts in E-Learning Design
NARCIS (Netherlands)
Westera, Wim
2009-01-01
Westera, W. (2006). The E-Learning Cabaret: do's and don'ts in E-Learning Design. Book of Abstracts, 12th International Conference on Technology Supported Learning & Teaching, Online Educa Berlin (pp. 169-171). November, 29-December, 1, 2006, Berlin, Germany: ICWE-GmbH.
18. Analysis of the Power oscillations event in Laguna Verde Nuclear Power Plant. Preliminary Report
International Nuclear Information System (INIS)
Gonzalez M, V.M.; Amador G, R.; Castillo, R.; Hernandez, J.L.
1995-01-01
The event occurred at Unit 1 of Laguna Verde Nuclear Power Plant in January 24, 1995, is analyzed using the Ramona 3 B code. During this event, Unit 1 suffered power oscillation when operating previous to the transfer at high speed recirculating pumps. This phenomenon was timely detected by reactor operator who put the reactor in shut-down doing a manual Scram. Oscillations reached a maximum extent of 10.5% of nominal power from peak to peak with a frequency of 0.5 Hz. Preliminary evaluations show that the event did not endangered the fuel integrity. The results of simulating the reactor core with Ramona 3 B code show that this code is capable to moderate reactor oscillations. Nevertheless it will be necessary to perform a more detailed simulation of the event in order to prove that the code can predict the beginning of oscillations. It will be need an additional analysis which permit the identification of factors that influence the reactor stability in order to express recommendations and in this way avoid the recurrence of this kind of events. (Author)
19. Don Quijote y los eruditos: Sobre la sátira quijotesca de la pedantería en la literatura francesa del siglo XVIII
OpenAIRE
Pardo García, Pedro Javier
1998-01-01
[ES]Este texto trata Don Quijote y los eruditos, una polémica crítica y sus implicaciones metacríticas. [EN]This text is Don Quixote and scholars, a critical controversy and its implications metacritical.
20. Participation of the ININ in the activities of radioactive waste management of the Laguna Verde Central
International Nuclear Information System (INIS)
Medrano L, M.; Rodriguez C, C.; Linares R, D.; Ramirez G, R.; Zarate M, N.
2006-01-01
From the beginning of the operation of the Laguna Verde Central (CLV) the National Institute of Nuclear Research (ININ) has come supporting the CLV in the activities of administration of the humid and dry radioactive waste generated by the operation of the two units of the CLV, from the elaboration of procedures to the temporary storage in site, the implementation of a program of minimization and segregation of dry solid wastes, until the classification of the lots of humid waste and bulk dry wastes. In this work the description of the management activities of radioactive wastes carried out by the ININ in the facilities of the CLV to the date is presented, as well as some actions that they are had drifted in the future near, among those that it stands out the determination of the total alpha activity in humid samples by means of scintillation analysis. (Author)
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http://sgtb.eu/examples/latest/examples/multiclass_classifier/multiclass_logisticregression.html
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# Multi-class Logistic Regression¶
Multinomial logistic regression assigns the sample $$\mathbf{x}_i$$ to class $$c$$ based on the probability for sample $$\mathbf{x}_i$$ to be in class $$c$$:
$P(Y_i = c | \mathbf{x}_i) = \frac{\exp(\mathbf{\theta}^\top_c\mathbf{x}_i)}{1+ \sum_{k=1}^{K}\exp(\mathbf{\theta}^\top_k\mathbf{x}_i)}$
in which $$K$$ is the number of classes.
The loss function that needs to be minimized is:
${\min_{\mathbf{\theta}}}\sum_{k=1}^{K}\sum_{i=1}^{m}w_{ik}\log(1+\exp(-y_{ik}(\mathbf{x}_k^\top\mathbf{a}_{ik} + c_k))) + \lambda\left \| \mathbf{x} \right \|_{l_1/l_q}$
where $$\mathbf{a}_{ik}$$ denotes the $$i$$-th sample for the $$k$$-th class, $$w_{ik}$$ is the weight for $$\mathbf{a}_{ik}^\top$$, $$y_{ik}$$ is the response of $$\mathbf{a}_{ik}$$, and $$c_k$$ is the intercept (scalar) for the $$k$$-th class. $$\lambda$$ is the $$l_1/l_q$$-norm regularization parameter.
## Example¶
Imagine we have files with training and test data. We create CDenseFeatures (here 64 bit floats aka RealFeatures) and CMulticlassLabels as
features_train = RealFeatures(f_feats_train)
features_test = RealFeatures(f_feats_test)
labels_train = MulticlassLabels(f_labels_train)
labels_test = MulticlassLabels(f_labels_test)
features_train = RealFeatures(f_feats_train);
features_test = RealFeatures(f_feats_test);
labels_train = MulticlassLabels(f_labels_train);
labels_test = MulticlassLabels(f_labels_test);
RealFeatures features_train = new RealFeatures(f_feats_train);
RealFeatures features_test = new RealFeatures(f_feats_test);
MulticlassLabels labels_train = new MulticlassLabels(f_labels_train);
MulticlassLabels labels_test = new MulticlassLabels(f_labels_test);
features_train = Shogun::RealFeatures.new f_feats_train
features_test = Shogun::RealFeatures.new f_feats_test
labels_train = Shogun::MulticlassLabels.new f_labels_train
labels_test = Shogun::MulticlassLabels.new f_labels_test
features_train <- RealFeatures(f_feats_train)
features_test <- RealFeatures(f_feats_test)
labels_train <- MulticlassLabels(f_labels_train)
labels_test <- MulticlassLabels(f_labels_test)
features_train = shogun.RealFeatures(f_feats_train)
features_test = shogun.RealFeatures(f_feats_test)
labels_train = shogun.MulticlassLabels(f_labels_train)
labels_test = shogun.MulticlassLabels(f_labels_test)
RealFeatures features_train = new RealFeatures(f_feats_train);
RealFeatures features_test = new RealFeatures(f_feats_test);
MulticlassLabels labels_train = new MulticlassLabels(f_labels_train);
MulticlassLabels labels_test = new MulticlassLabels(f_labels_test);
auto features_train = some<CDenseFeatures<float64_t>>(f_feats_train);
auto features_test = some<CDenseFeatures<float64_t>>(f_feats_test);
auto labels_train = some<CMulticlassLabels>(f_labels_train);
auto labels_test = some<CMulticlassLabels>(f_labels_test);
We create an instance of the CMulticlassLogisticRegression classifier by passing it the dataset, lables, and specifying the regularization constant $$\lambda$$ for each machine
classifier = MulticlassLogisticRegression(1, features_train, labels_train)
classifier = MulticlassLogisticRegression(1, features_train, labels_train);
MulticlassLogisticRegression classifier = new MulticlassLogisticRegression(1, features_train, labels_train);
classifier = Shogun::MulticlassLogisticRegression.new 1, features_train, labels_train
classifier <- MulticlassLogisticRegression(1, features_train, labels_train)
classifier = shogun.MulticlassLogisticRegression(1, features_train, labels_train)
MulticlassLogisticRegression classifier = new MulticlassLogisticRegression(1, features_train, labels_train);
auto classifier = some<CMulticlassLogisticRegression>(1, features_train, labels_train);
Then we train and apply it to test data, which here gives CMulticlassLabels.
classifier.train()
labels_predict = classifier.apply_multiclass(features_test)
classifier.train();
labels_predict = classifier.apply_multiclass(features_test);
classifier.train();
MulticlassLabels labels_predict = classifier.apply_multiclass(features_test);
classifier.train
labels_predict = classifier.apply_multiclass features_test
classifier$train() labels_predict <- classifier$apply_multiclass(features_test)
classifier:train()
labels_predict = classifier:apply_multiclass(features_test)
classifier.train();
MulticlassLabels labels_predict = classifier.apply_multiclass(features_test);
classifier->train();
auto labels_predict = classifier->apply_multiclass(features_test);
We can evaluate test performance via e.g. CMulticlassAccuracy.
eval = MulticlassAccuracy()
accuracy = eval.evaluate(labels_predict, labels_test)
eval = MulticlassAccuracy();
accuracy = eval.evaluate(labels_predict, labels_test);
MulticlassAccuracy eval = new MulticlassAccuracy();
double accuracy = eval.evaluate(labels_predict, labels_test);
eval = Shogun::MulticlassAccuracy.new
accuracy = eval.evaluate labels_predict, labels_test
eval <- MulticlassAccuracy()
accuracy <- eval\$evaluate(labels_predict, labels_test)
eval = shogun.MulticlassAccuracy()
accuracy = eval:evaluate(labels_predict, labels_test)
MulticlassAccuracy eval = new MulticlassAccuracy();
double accuracy = eval.evaluate(labels_predict, labels_test);
auto eval = some<CMulticlassAccuracy>();
auto accuracy = eval->evaluate(labels_predict, labels_test);
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https://www.albert.io/ie/general-chemistry/calculating-the-molar-mass-of-an-ideal-gas
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Free Version
Moderate
Calculating the Molar Mass of an Ideal Gas
CHEM-01MBY1
If $1.76\text{ g}$ of an ideal gas occupy $1.0\text{ L}$ at standard temperature and pressure (STP), what is the molar mass of the gas?
$\left(R=0.0821\cfrac{L\times atm}{mol\times K}\right)$
A
$4.0\text{ g/mol}$
B
$16\text{ g/mol}$
C
$20\text{ g/mol}$
D
$40\text{ g/mol}$
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https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=132&t=41677&p=142789
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## 9.25, Calculation
Boltzmann Equation for Entropy: $S = k_{B} \ln W$
Douglas Nguyen 2J
Posts: 71
Joined: Fri Sep 28, 2018 12:15 am
### 9.25, Calculation
"9.25 If SO2F2 adopts a positionally disordered arrangement in its crystal form, what might its residual molar entropy be?"
When calculating entropy using S=k(b)lnW, the solutions manual states that W is 6^(6.02214*10^23). Is the exponent just based on the number of molecules/units involved in the reaction?
Posts: 60
Joined: Tue Nov 28, 2017 3:02 am
### Re: 9.25, Calculation
Yes, since the Boltzmann Formula relates entropy and how the molecules arrange in said micro-states:
Thus 6 ^ avogadro's number would be W.
Return to “Third Law of Thermodynamics (For a Unique Ground State (W=1): S -> 0 as T -> 0) and Calculations Using Boltzmann Equation for Entropy”
### Who is online
Users browsing this forum: No registered users and 2 guests
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https://www.physicsforums.com/threads/coulombs-law-use.485130/
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# Coulomb's law use
• Start date
• #1
4
0
1. The problem statement, all variables given/known data
A particle of charge 6 µC is held fixed while another particle of charge 8 µC is released
from rest at a distance of 1.4 m from the first particle. If the mass of the second particle is
3x10-6 kg, what is its speed when it is very far away from the first particle?
F=ma
F= kQ1Q2 / r2
## The Attempt at a Solution
I pretty much worked through most the problem. In the end, I used coulomb's law in combination with newtons 2nd law to get a= 73469 m/s2. However what's bugging me is the distance that the speed is "very far away". I'm under the assumption that means at a point where the force from the first particle no longer affects the second. However, when I back-tracked using the answer(454m/s) the distance ends up being 1.4( the original distance) with the velocity equations.
Related Introductory Physics Homework Help News on Phys.org
• #2
4
0
Apologies, I searched google and found a similar problem: rocket is launched straight up from the earth's surface at a speed of 1.60×10^4 m/s.
What is its speed when it is very far away from the earth?
One of the helpers suggested conservation of energy, and I applied this to this problem it worked! Sorry!
• #3
gneill
Mentor
20,801
2,778
You do realize that the acceleration is not constant? It decreases as the distance between the particles grows. So your V2 = Vo + 2ad formula is not valid over the trajectory of the second particle.
Why not try a conservation of energy approach?
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https://128.84.21.199/abs/2001.01949
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# Title:Numerical solution of a two dimensional tumour growth model with moving boundary
Abstract: We consider a biphasic continuum model for avascular tumour growth in two spatial dimensions, in which a cell phase and a fluid phase follow conservation of mass and momentum. A limiting nutrient that follows a diffusion process controls the birth and death rate of the tumour cells. The cell volume fraction, cell velocity - fluid pressure system, and nutrient concentration are the model variables. A coupled system of a hyperbolic conservation law, a viscoelastic system, and a parabolic diffusion equation governs the dynamics of the model variables. The tumour boundary moves with the normal velocity of the outermost layer of cells, and this time-dependence is a challenge in designing and implementing a stable and fast numerical scheme. We recast the model into a form where the hyperbolic equation is defined on a fixed extended domain and retrieve the tumour boundary as the interface at which the cell volume fraction decreases below a threshold value. This procedure eliminates the need to track the tumour boundary explicitly and the computationally expensive re-meshing of the time-dependent domains. A numerical scheme based on finite volume methods for the hyperbolic conservation law, Lagrange $\mathbb{P}_2 - \mathbb{P}_1$ Taylor-Hood finite element method for the viscoelastic system, and mass-lumped finite element method for the parabolic equations is implemented in two spatial dimensions, and several cases are studied. We demonstrate the versatility of the numerical scheme in catering for irregular and asymmetric initial tumour geometries. When the nutrient diffusion equation is defined only in the tumour region, the model depicts growth in free suspension. On the contrary, when the nutrient diffusion equation is defined in a larger fixed domain, the model depicts tumour growth in a polymeric gel.
Comments: 24 pages, 51 figures, numerical solution without nre-meshing the time-depdendent domain Subjects: Numerical Analysis (math.NA) MSC classes: 35Q92, 65M08, 65M50, 5R37 Cite as: arXiv:2001.01949 [math.NA] (or arXiv:2001.01949v1 [math.NA] for this version)
## Submission history
From: Gopikrishnan C Remesan [view email]
[v1] Tue, 7 Jan 2020 10:05:30 UTC (5,659 KB)
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https://www.dsprelated.com/freebooks/filters/Elementary_Filter_Sections.html
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## Elementary Filter Sections
This section gives condensed analysis summaries of the four most elementary digital filters: the one-zero, one-pole, two-pole, and two-zero filters. Despite their relative simplicity, they are quite valuable to master in practice. In particular, recall from Chapter 9 that every causal, finite-order, LTI filter (any difference equation of the form Eq.(5.1)) may be factored into a series and/or parallel combinationof such sections. Implementing high-order filters as parallel and/or series combinations of low-order sections offers several advantages, such as numerical robustness and easier/safer control in real time.
### One-Zero
Figure B.1 gives the signal flow graph for the general one-zero filter. The frequency response for the one-zero filter may be found by the following steps:
By factoring out from the frequency response, to balance the exponents of , we can get this closer to polar form as follows:
We now apply the general equations given in Chapter 7 for filter gain and filter phase as a function of frequency:
A plot of and for and various real values of , is given in Fig.B.2. The filter has a zero at in the plane, which is always on the real axis. When a point on the unit circle comes close to the zero of the transfer function the filter gain at that frequency is low. Notice that one real zero can basically make either a highpass ( ) or a lowpass filter ( ). For the phase response calculation using the graphical method, it is necessary to include the pole at .
### One-Pole
Fig.B.3 gives the signal flow graph for the general one-pole filter. The road to the frequency response goes as follows:
The one-pole filter has a transfer function (hence frequency response) which is the reciprocal of that of a one-zero. The analysis is thus quite analogous. The frequency response in polar form is given by
A plot of the frequency response in polar form for and various values of is given in Fig.B.4.
The filter has a pole at , in the plane (and a zero at = 0). Notice that the one-pole exhibits either a lowpass or a highpass frequency response, like the one-zero. The lowpass character occurs when the pole is near the point (dc), which happens when approaches . Conversely, the highpass nature occurs when is positive.
The one-pole filter section can achieve much more drastic differences between the gain at high frequencies and the gain at low frequencies than can the one-zero filter. This difference is achieved in the one-pole by gain boost in the passband rather than attenuation in the stopband; thus it is usually desirable when using a one-pole filter to set to a small value, such as , so that the peak gain is 1 or so. When the peak gain is 1, the filter is unlikely to overflow.B.1
Finally, note that the one-pole filter is stable if and only if .
### Two-Pole
The signal flow graph for the general two-pole filter is given in Fig.B.5. We proceed as usual with the general analysis steps to obtain the following:
The numerator of is a constant, so there are no zeros other than two at the origin of the plane.
The coefficients and are called the denominator coefficients, and they determine the two poles of . Using the quadratic formula, the poles are found to be located at
When the coefficients and are real (as we typically assume), the poles must be either real (when ) or form a complex conjugate pair (when ).
When both poles are real, the two-pole can be analyzed simply as a cascade of two one-pole sections, as in the previous section. That is, one can multiply pointwise two magnitude plots such as Fig.B.4a, and add pointwise two phase plots such as Fig.B.4b.
When the poles are complex, they can be written as
since they must form a complex-conjugate pair when and are real. We may express them in polar form as
where
is the pole radius, or distance from the origin in the -plane. As discussed in Chapter 8, we must have for stability of the two-pole filter. The angles are the poles' respective angles in the plane. The pole angle corresponds to the pole frequency via the relation
where denotes the sampling interval. See Chapter 8 for a discussion and examples of pole-zero plots in the complex -plane.
If is sufficiently large (but less than 1 for stability), the filter exhibits a resonanceB.2 at radian frequency . We may call or the center frequency of the resonator. Note, however, that the resonance frequency is not usually the precise frequency of peak-gain in a two-pole resonator (see Fig.B.9 on page ). The peak of the amplitude response is usually a little different because each pole sits on the other's skirt,'' which is slanted. (See §B.1.5 and §B.6 for an elaboration of this point.)
Using polar form for the (complex) poles, the two-pole transfer function can be expressed as
(B.1)
Comparing this to the transfer function derived from the difference equation, we may identify
The difference equation can thus be rewritten as
(B.2)
Note that coefficient depends only on the pole radius R (which determines damping) and is independent of the resonance frequency, while is a function of both. As a result, we may retune the resonance frequency of the two-pole filter section by modifying only.
The gain at the resonant frequency , is found by substituting into Eq.(B.1) to get
(B.3)
See §B.6 for details on how the resonance gain (and peak gain) can be normalized as the tuning of is varied in real time.
Since the radius of both poles is , we must have for filter stability8.4). The closer is to 1, the higher the gain at the resonant frequency . If , the filter degenerates to the form , which is a nothing but a scale factor. We can say that when the two poles move to the origin of the plane, they are canceled by the two zeros there.
#### ResonatorBandwidth in Terms of Pole Radius
The magnitude of a complex pole determines the damping or bandwidth of the resonator. (Damping may be defined as the reciprocal of the bandwidth.)
As derived in §8.5, when is close to 1, a reasonable definition of 3dB-bandwidth is provided by
(B.4) (B.5)
where is the pole radius, is the bandwidth in Hertz (cycles per second), and is the sampling interval in seconds.
Figure B.6 shows a family of frequency responses for the two-pole resonator obtained by setting and varying . The value of in all cases is , corresponding to . The analytic expressions for amplitude and phase response are
where and .
### Two-Zero
The signal flow graph for the general two-zero filter is given in Fig.B.7, and the derivation of frequency response is as follows:
As discussed in §5.1, the parameters and are called the numerator coefficients, and they determine the two zeros. Using the quadratic formula for finding the roots of a second-order polynomial, we find that the zeros are located at
If the zeros are real [ ], then the two-zero case reduces to two instances of our earlier analysis for the one-zero. Assuming the zeros to be complex, we may express the zeros in polar form as and , where .
Forming a general two-zero transfer function in factored form gives
from which we identify and , so that
is again the difference equation of the general two-zero filter with complex zeros. The frequency , is now viewed as a notch frequency, or antiresonance frequency. The closer R is to 1, the narrower the notch centered at .
The approximate relation between bandwidth and given in Eq.(B.5) for the two-pole resonator now applies to the notch width in the two-zero filter.
Figure B.8 gives some two-zero frequency responses obtained by setting to 1 and varying . The value of , is again . Note that the response is exactly analogous to the two-pole resonator with notches replacing the resonant peaks. Since the plots are on a linear magnitude scale, the two-zero amplitude response appears as the reciprocal of a two-pole response. On a dB scale, the two-zero response is an upside-down two-pole response.
### Complex Resonator
Normally when we need a resonator, we think immediately of the two-pole resonator. However, there is also a complex one-pole resonator having the transfer function
(B.6)
where is the single complex pole, and is a scale factor. In the time domain, the complex one-pole resonator is implemented as
Since is complex, the output is generally complex even when the input is real.
Since the impulse response is the inverse z transform of the transfer function, we can write down the impulse response of the complex one-pole resonator by recognizing Eq.(B.6) as the closed-form sum of an infinite geometric series, yielding
where, as always, denotes the unit step function:
Thus, the impulse response is simply a scale factor times the geometric sequence with the pole as its term ratio''. In general, is a sampled, exponentially decaying sinusoid at radian frequency . By setting somewhere on the unit circle to get
we obtain a complex sinusoidal oscillator at radian frequency rad/sec. If we like, we can extract the real and imaginary parts separately to create both a sine-wave and a cosine-wave output:
These may be called phase-quadrature sinusoids, since their phases differ by 90 degrees. The phase quadrature relationship for two sinusoids means that they can be regarded as the real and imaginary parts of a complex sinusoid.
By allowing to be complex,
we can arbitrarily set both the amplitude and phase of this phase-quadrature oscillator:
The frequency response of the complex one-pole resonator differs from that of the two-pole real resonator in that the resonance occurs only for one positive or negative frequency , but not both. As a result, the resonance frequency is also the frequency where the peak-gain occurs; this is only true in general for the complex one-pole resonator. In particular, the peak gain of a real two-pole filter does not occur exactly at resonance, except when , , or . See §B.6 for more on peak-gain versus resonance-gain (and how to normalize them in practice).
#### Two-PolePartial Fraction Expansion
Note that every real two-pole resonator can be broken up into a sum of two complex one-pole resonators:
(B.7)
where and are constants (generally complex). In this parallel one-pole'' form, it can be seen that the peak gain is no longer equal to the resonance gain, since each one-pole frequency response is tilted'' near resonance by being summed with the skirt'' of the other one-pole resonator, as illustrated in Fig.B.9. This interaction between the positive- and negative-frequency poles is minimized by making the resonance sharper ( ), and by separating the pole frequencies . The greatest separation occurs when the resonance frequency is at one-fourth the sampling rate ( ). However, low-frequency resonances, which are by far the most common in audio work, suffer from significant overlapping of the positive- and negative-frequency poles.
To show Eq.(B.7) is always true, let's solve in general for and given and . Recombining the right-hand side over a common denominator and equating numerators gives
which implies
The solution is easily found to be
where we have assumed im, as necessary to have a resonator in the first place.
Breaking up the two-pole real resonator into a parallel sum of two complex one-pole resonators is a simple example of a partial fraction expansion (PFE) (discussed more fully in §6.8).
Note that the inverse z transform of a sum of one-pole transfer functions can be easily written down by inspection. In particular, the impulse response of the PFE of the two-pole resonator (see Eq.(B.7)) is clearly
Since is real, we must have , as we found above without assuming it. If , then is a real sinusoid created by the sum of two complex sinusoids spinning in opposite directions on the unit circle.
### The BiQuad Section
The term biquad'' is short for bi-quadratic'', and is a common name for a two-pole, two-zero digital filter. The transfer function of the biquad can be defined as
(B.8)
where can be called the overall gain of the biquad. Since both the numerator and denominator of this transfer function are quadratic polynomials in (or ), the transfer function is said to be bi-quadratic'' in (or ).
As derived in §B.1.3, for real second-order polynomials having complex roots, it is often convenient to express the polynomial coefficients in terms of the radius and angle of the positive-frequency pole. For example, denoting the denominator polynomial by , we have
This representation is most often used for the denominator of the biquad, and we think of as the resonance frequency (in radians per sample-- , where is the resonance frequency in Hz), and determines the Q'' of the resonance (see §B.1.3). The numerator is less often represented in this way, but when it is, we may think of the zero-angle as the antiresonance frequency, and the zero-radius affects the depth and width of the antiresonance (or notch).
As discussed on page , a common setting for the zeros when making a resonator is to place one at (dc) and the other at (half the sampling rate), i.e., and in Eq.(B.8) above . This zero placement normalizes the peak gain of the resonator if it is swept using the parameter.
Using the shift theorem for z transforms, the difference equation for the biquad can be written by inspection of the transfer function as
where denotes the input signal sample at time , and is the output signal. This is the form that is typically implemented in software. It is essentially the direct-form I implementation. (To obtain the official direct-form I structure, the overall gain must be not be pulled out separately, resulting in feedforward coefficients instead. See Chapter 9 for more about filter implementation forms.)
### Biquad Software Implementations
In matlab, an efficient biquad section is implemented by calling
outputsignal = filter(B,A,inputsignal);
where
A complete C++ class implementing a biquad filter section is included in the free, open-source Synthesis Tool Kit (STK) [15]. (See the BiQuad STK class.)
Figure B.10 lists an example biquad implementation in the C programming language.
typedef double *pp; // pointer to array of length NTICK typedef word double; // signal and coefficient data type typedef struct _biquadVars { pp output; pp input; word s2; word s1; word gain; word a2; word a1; word b2; word b1; } biquadVars; void biquad(biquadVars *a) { int i; dbl A; word s0; for (i=0; igain * a->input[i]; A -= a->a1 * a->s1; A -= a->a2 * a->s2; s0 = A; A += a->b1 * a->s1; a->output[i] = a->b2 * a->s2 + A; a->s2 = a->s1; a->s1 = s0; } }
Next Section:
Allpass Filter Sections
Previous Section:
A Sum of Sinusoids at the Same Frequency is Another Sinusoid at that Frequency
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http://mathhelpforum.com/calculus/183658-definite-integrals-lnx.html
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# Thread: definite integrals lnx
1. ## definite integrals lnx
I have an integration whose lower limit has resulted in a negative number. What happens here? So for example;
ln (4/-2)
Does this mean it is equal to zero?
2. ## Re: definite integrals lnx
Originally Posted by Googl
I have an integration whose lower limit has resulted in a negative number. What happens here? So for example;
ln (4/-2)
Does this mean it is equal to zero?
no ... if the log function was the result of integration, you should know that the log's argument involves an absolute value.
3. ## Re: definite integrals lnx
Originally Posted by Googl
I have an integration whose lower limit has resulted in a negative number. What happens here? So for example; ln (4/-2)
Does this mean it is equal to zero?
Why don't you post the actual question?
I for one, have no idea what that question means.
4. ## Re: definite integrals lnx
Originally Posted by skeeter
no ... if the log function was the result of integration, you should know that the log's argument involves an absolute value.
Thanks.
As in ln (4/2) instead of ln (4/-2)
The question is long.
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https://export.arxiv.org/abs/2009.09564
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### Current browse context:
cond-mat.stat-mech
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# Title: Geometric Mean of Concentrations and Reversal Permanent Charge in Zero-Current Ionic Flows via Poisson-Nernst-Planck Models
Authors: Hamid Mofidi
Abstract: This work examines the geometric mean of concentrations and its behavior in various situations, as well as the reversal permanent charge problem, the charge sharing seen in x-ray diffraction. Observations are obtained from analytical results established using geometric singular perturbation analysis of classical Poisson-Nernst-Planck models.
For ionic mixtures of multiple ion species Mofidi and Liu [{\em SIAM J. Appl. Math. {\bf 80} (2020), 1908-1935}] centered two ion species with unequal diffusion constants to acquire a system for determining the reversal potential and reversal permanent charge. They studied the reversal potential problem and its dependence on diffusion coefficients, membrane potential, membrane concentrations, etc. Here we use the same approach to study the dual problem of reversal permanent charges and its dependence on other conditions. We consider two ion species with positive and negative charges, say Ca$^+$ and Cl$^-$, to determine the specific conditions under which the permanent charge is unique. Furthermore, we investigate the behavior of geometric mean of concentrations for various values of transmembrane potential and permanent charge.
Comments: 23 pages, 8 figures Subjects: Statistical Mechanics (cond-mat.stat-mech); Mathematical Physics (math-ph); Dynamical Systems (math.DS) MSC classes: 34N05 Cite as: arXiv:2009.09564 [cond-mat.stat-mech] (or arXiv:2009.09564v1 [cond-mat.stat-mech] for this version)
## Submission history
From: Hamidreza Mofidi [view email]
[v1] Mon, 21 Sep 2020 01:32:43 GMT (540kb,D)
Link back to: arXiv, form interface, contact.
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https://math-quiz.co.uk/start_test.php?id=70
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# Test: Angles, Straight Lines - Ambitious
Double click on maths expressions to zoom
Question 1: How many degrees are in $2.5$ right angles?
$112.5°$
$225°$
$235°$
$240°$
Question 2: How many degrees are in $\frac{1}{3}$ of a right angle?
$60°$
$120°$
$90°$
$30°$
Question 3: Find an angle corresponding to $\frac{3}{5}$ revolution?
$72°$
$200°$
$216°$
$270°$
Question 4: Find an angle corresponding to $\frac{5}{18}$ revolution?
$70°$
$60°$
$100°$
$90°$
Question 5: Two angles are complementary. One of them is $73°$. What is the other angle?
$27°$
$283°$
$167°$
$17°$
Please note, you have solved only half of the test. For the complete test get a Must Have account. Get started
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https://eprints.soton.ac.uk/260941/
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The University of Southampton
University of Southampton Institutional Repository
# Adaptive near minimum error rate training for neural networks with application to multiuser detection in CDMA communication systems
Chen, S., Samingan, A.K. and Hanzo, L. (2005) Adaptive near minimum error rate training for neural networks with application to multiuser detection in CDMA communication systems. Signal Processing, 85 (7), 1435-1448.
Record type: Article
## Abstract
Adaptive training of neural networks is typically done using some stochastic gradient algorithm that tries to minimize the mean square error (MSE). For many applications, such as channel equalization and code-division multiple-access (CDMA) multiuser detection, the goal is to minimize the error probability. For these applications, adopting the MSE criterion may lead to a poor performance. A novel adaptive near minimum error rate algorithm called the least bit error rate (LBER) is developed for training neural networks for these kinds of applications. The proposed method is applied to multiuser detection in CDMA communication systems. Simulation results show that the LBER algorithm has a good convergence speed and a small radial basis function (RBF) network trained by this adaptive algorithm can closely match the performance of the optimal Bayesian multiuser detector. The results also confirm that training the neural network multiuser detector using the least mean square (LMS) algorithm, although converging well in the MSE, can produce a poor error rate performance.
PDF
science.pdf - Other
Published date: July 2005
Organisations: Southampton Wireless Group
## Identifiers
Local EPrints ID: 260941
URI: https://eprints.soton.ac.uk/id/eprint/260941
ISSN: 0165-1684
PURE UUID: 68f0368d-93b0-42c4-af33-9f14b755380f
ORCID for L. Hanzo: orcid.org/0000-0002-2636-5214
## Catalogue record
Date deposited: 06 Jun 2005
## Contributors
Author: S. Chen
Author: A.K. Samingan
Author: L. Hanzo
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http://linux304.utsp.utwente.nl/view/classification/MSC-35Q53.html
|
EEMCS
Home > Publications
Education Research Prospective Students Jobs Publications Intranet (internal) Nederlands Contact Search Organisation
EEMCS EPrints Service
Classification: MSC-35Q53 Home Policy Brochure Browse Search User Area Contact Help
2007
Derks, G. and Doelman, A. and van Gils, S.A. and Susanto, H. (2007) Stability analysis of π-kinks in a 0-π Josephson junction. SIAM Journal on Applied Dynamical Systems (SIADS), 6 (1). pp. 99-141. ISSN 1536-0040 *** ISI Impact 1,819 ***
2006
Kersten, P.H.M. and Krasil'shchik, I. and Verbovetsky, A.V. (2006) A geometric study of the dispersionless Boussinesq type equation. Acta Applicandae Mathematicae, 90 (1-2). pp. 143-178. ISSN 0167-8019 *** ISI Impact 0,853 ***
Xu, Yan and Shu, C.-W. (2006) Local discontinuous Galerkin methods for the Kuramoto-Sivashinsky equations and the Ito-type coupled KdV equations. Computer Methods in Applied Mechanics and Engineering, 195 (25-28). pp. 3430-3447. ISSN 0045-7825 *** ISI Impact 3,467 ***
2005
Verbovetsky, A.V. and Kersten, P.H.M. and Krasil'shchik, I. (2005) The D-Boussinesq equation: Hamiltonian and symplectic structures; Noether and inverse Noether operators. Memorandum 1752, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
2004
Kersten, P.H.M. and Krasil'shchik, I. and Verbovetsky, A.V. (2004) The Monge-Ampère equation: Hamiltonian and symplectic structures, recursions, and hierarchies. Memorandum 1727, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
2003
Helminck, G.F. (2003) -Functions for a two-point version of the -hierarchy. Memorandum 1671, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
2002
Igonin, S. and Martini, R. (2002)
Prolongation structure of the Krichever-Novikov equation.
Memorandum 1638, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
Kersten, P.H.M. and Krasil'shchik, I. (2002)
From recursion operators to Hamiltonian structures. The factorization method.
Memorandum 1624, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
Kersten, P.H.M. and Krasil'shchik, I. and Verbovetsky, A.V. (2002)
Hamiltonian operators and -coverings.
Memorandum 1640, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
Kersten, P.H.M. and Krasil'shchik, I. and Verbovetsky, A.V. (2002)
An extensive study of the supersymmetric KDV equation.
Memorandum 1656, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
Kersten, P.H.M. and Sorin, A.S. (2002)
Bi-Hamiltonian structure of the supersymmetric KdV hierarchy.
Memorandum 1615, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
Sorin, A.S. and Kersten, P.H.M. (2002) The supersymmetric unconstrained matrix GNLS hierarchies. Memorandum 1613, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
2000
Helminck, G.F. (2000)
The AKNS-hierarchy.
Memorandum 1534, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
Helminck, G.F. and van de Leur, J.W. (2000)
Darboux transformations for the KP hierarchy in the Segal-Wilson setting.
Memorandum 1535, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
Helminck, G.F. and van de Leur, J.W. (2000) Geometric Bäcklund-Darboux transformations for the KP hierarchy. Memorandum 1556, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
1998
van de Leur, J.W. and Martini, R. (1998)
The construction of Frobenius manifolds from KP tau-functions.
Memorandum 1456, Department of Applied Mathematics, University of Twente, Enschede. ISSN 0169-2690
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http://physics.stackexchange.com/questions/105503/would-gravity-on-the-surface-of-a-planet-which-is-being-consumed-by-a-black-hole
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# Would gravity on the surface of a planet which is being consumed by a black hole change?
Assuming that the black hole starts grow in the exact center of the planet and that the general structure of the planet does not degrade as it is eaten from the inside, would the gravity on the surface of the planet be affected by the black hole growing.
My uneducated guess is that as the matter becomes more compacted the gravity on the surface would actually decrease due to the fact that the distance to the mass, with respect to the surface, is increasing.
Also would the evaporation of the black hole actually decrease the total amount of mass in the center of the planet?
-
Assuming that the center of the planet just collapses to a black hole, people on the surface won't notice any difference in gravity at all until the ground starts to fall out from under them (the planet will no longer be stable, as there will be no way to support the ground under your feet, ultimately).
This is due to a result known as Birchoff's theorem that says that one can treat any spherically symmetric mass distribution as if all of its mass were concentrated at it's center.
-
Ah I see now, for every piece of matter that is now farther away from any given point on the surface there is an equal amount of matter that is closer as well. Would the total amount of matter actually decrease due to hawking radiation? – Peter Micheal Lacey-Bordeaux Mar 28 at 17:43
@PeterMichealLacey-Bordeaux: If you're taking about an Earth-sized black hole, you'd have to wait an age of the universe to see anything measurable, but probably. – Jerry Schirmer Mar 28 at 19:11
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https://www.alfajango.com/blog/how-to-combine-gzip-plus-cdn-for-fastest-page-loads/
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# How to Combine GZip + CDN for Fastest Page Loads
11 June 2010
This is Article #3 of a 4-part series. For a good primer, check out the first two articles listed below. Otherwise, jump right in!
In my last post, I discussed the three techniques used to improve asset load speed. In this post, I will discuss how to combine the use of GZipping and a Content Delivery Network (CDN) for the fastest possible page loads.
## Pitfall of Amazon S3 + CloudFront
Everyone's favorite CDN these days is Amazon's CloudFront service, which serves files directly from Amazon's scalable "simple storage system", Amazon S3. It is very easy to work with, has widespread support in Ruby gems and plugins (and countless other libraries), and is very inexpensive with it's pay-as-you-go billing.
However, there is one large pitfall to using Amazon S3 + CloudFront, and that is that neither S3 nor CloudFront support GZip detecting and encoding. It would seem that we need to now decide whether we'll do without GZipping or using a CDN. Not so! There is another way.
## Possible Solutions (that don't work)
If you're not interested in the solutions that won't work, you may skip straight to the solution that does work.
Amazon S3 and CloudFront servers do not detect whether the incoming requests accept GZip encoding, and so they are not able to Gzip and serve components on the fly. Then, it's simply a matter of figuring out whether we should link to the compressed or the uncompressed components when the user visits the page.
Note that even though Amazon's S3 servers cannot GZip and serve GZipped components on the fly, we could still zip our components beforehand and upload the compressed versions to S3 (as long as the Content-encoding header is set to "gzip" for the gzipped version being uploaded to S3). Most modern browsers support gzip encoding currently, so this won't be a problem most of the time. However, if the user does have a browser that does not support gzip encoding, your site's zipped stylesheets and javascripts simply will not work for that user. This may be ok for you. For the rest of this article, though, we will assume this is unacceptable.
### Detect requests with application and write asset URLs accordingly
This solution is similar to the last, except that it attacks the problem one step earlier in the workflow. So, let's take a step back. Instead of linking to the asset through our own server, this time, we'll revert to linking directly to CloudFront:
<link href="http://xxxxxx.cloudfront.net/stylesheets/application.css" media="screen" rel="stylesheet" type="text/css" />
However, this time we'll have our application (whether it be Ruby, PHP, Python, or whatever) detect if the request header accepts GZip encoding, and rewrite the asset tag accordingly.
<link href="http://xxxxxx.cloudfront.net/stylesheets/application.css.gz" media="screen" rel="stylesheet" type="text/css" />
I won't go into detail about how to actually accomplish this, because the truth is, this won't work either.
Edit: As one reader pointed out over on Hacker News, this solution works perfectly fine if your page or site is already uncachable to begin with. In other words, if you cannot cache your site for other reasons, you might as well use this solution.
#### Why this doesn't work
This will only work as long as your code is run dynamically every time a user loads the page. That means, once you implement this strategy, you no longer have the option to cache the page. Ever.
Sure, you could probably come up with some system that creates two versions of each cached page (one with gzipped links and one without), but that will add a lot of complexity to your server setup and filesystem, and it's just too much trouble. So, let's move on to another solution.
### Intercept CloudFront requests with app server and rewrite
Now this first solution may seem clever, but let's see if you can figure out why it won't work. The idea here is that rather link to a stylesheet, for example, on CloudFront like this:
<link href="http://xxxxxx.cloudfront.net/stylesheets/application.css" media="screen" rel="stylesheet" type="text/css" />
...we'll instead link to our own server, which will read the request and redirect to either the compressed or the uncompressed stylesheet on CloudFront as appropriate.
<link href="http://compressed.yourdomain.com/stylesheets/application.css" media="screen" rel="stylesheet" type="text/css" />
And then the Apache configuration for the compressed.yourdomain.com virtual host would look like this:
<VirtualHost *:80>
ServerName compressed.yourdomain.com
DocumentRoot /home/user/yourapp/current/public
RewriteEngine On
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} -s
RewriteRule ^(.+) http://xxxxxx.cloudfront.net\$1.gz
</VirtualHost>
Note that this particular example first checks if the GZipped file exists on the local filesystem (see Apache's RewriteCond docs for more info), then redirects to the GZipped file on CloudFront. So, your local public folder must be sync'd with S3/CloudFront for this to work.
#### Why this doesn't work
Remember in the last article, one of the added benefits of off-loading your assets to a CDN is that your server no longer must listen for and respond to asset requests. This solution rescinds that benefit; even though the asset download still takes place between the CDN server and the user's browser, the initial request must still go through your server to be resolved to the CDN.
Furthermore, each component request now requires two DNS lookups instead of one, which adds to the request latency (though the request is latency is small compared to the download time in the request/download cycle).
But the real reason this won't work well is because it disrupts the magic that make CDNs fast. A CDN is beneficial primarily because serves files faster by choosing, for each request, the server (or "service node") that is closest in proximity to the user. CDNs are able to estimate the closest server in the CDN using a variety of techniques, including reactive probing, proactive probing, and connection monitoring. (See Content Networking Techniques for more info)
By inserting your server (acting as a proxy) into the request cycle between the user's computer and the CDN, you may cause the CDN to choose a sub-optimal service node for the delivery of content directly to the user. If the CDN probes the network from the request side, it will most likely choose the edge node location closest to your server rather than to the user's computer, completely negating the benefit of using the CDN in the first place.
To illustrate this point, consider the typical request/download cycle for a javascript file served from your application's server:
In the above chart, note that the majority of the User wait time is on the File Download side of the cycle. The User Request typically carries around 300 bytes of data, while the javascript file being downloaded would typically be anywhere from 10X to 100X (or more) as much data.
Below is a simplified diagram of the typical request/response cycle for a javascript file when using a CDN to serve the component.
Note that the forwarded requests are much "cheaper" in terms of response time than the file download, due to the huge difference in the amount of data being transferred. This is why it's still much faster to forward a request a few times in order to make the actual file download as efficient as possible.
This final diagram depicts the request/response cycle when delivery components through the CDN with your application server acting as a proxy (so that your app server can read the request and tell the CDN whether to serve the unzipped or the zipped component).
Notice in the diagram above, the CDN should have chosen the service node closest to the User, so that the javascript file would have less distance to travel and would thus download the fastest. Instead, it chose the node closer to the application server that proxied the request to the CDN.
The graph below compares download times for the user from my server (located in St. Louis, Missouri), from a server in Amazon CloudFront's CDN, and from CloudFront with my server acting as a proxy. I performed this comparison from my own computer here in Ann Arbor, MI, while my buddy, Dave Leal, downloaded the file from his computer in Portugal.
## The Solution: Hybrid Gzipping/CloudFront Depending on Asset-type
At this point, it may seem like we can choose between two alternatives:
• Move all assets to the Amazon CloudFront and forget about GZipping
• Keep components self-hosted and configure our server to detect incoming requests and perform on-the-fly GZipping as appropriate
In our last post, we saw that Gzipping our components can compress them down to ~25% of their original size, which means they'll transfer 4X faster. And in this post, we see that serving components from Amazon CloudFront can transfer component files ~2X faster*.
*This last statement depends entirely upon your CDN and your own server's location and capabilities, so you might want to do a little homework and verify the difference in download times for your own setup.
Ideally we'd be able to do both (and some other more expensive Content Delivery Networks actually will allow you to). But if we must choose, compressible file-types gain much more by way of serving them compressed, than by serving them uncompressed from a CDN edge location. So, we will serve compressible file-types (stylesheets, javascripts, and static HTML files) from our own server, GZipped.
However, images are already compressed in the image encoding; image file size is unaffected by Gzipping them on our server. So, we may as well allow images to benefit from the 2X speed improvement by serving them straight from our Amazon CloudFront CDN.
Using this solution for hosting/serving components, we've been able to reduce page load time by 75% on several of our sites.
If you have a Ruby on Rails application, implementing this solution is easy, and won't take you more than an hour or so. Stay tuned for Part 4: Caching, Zipping, and (Amazon CloudFront) CDN For A Rails App.
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|
https://www.calculators.tech/covariance-calculator
|
Covariance Calculator
Enter Information
RESULTS
Fill the calculator form and click on Calculate button to get result here
Get Custom Built Calculator For Your Website
OR
Get Covariance Calculator For Your Website
Covariance calculator can be used to calculate the relationship between the two commonly described sets of variables X and Y. Hence, It allows us to understand the relation between two sets of data.
Apart from calculating covariance, it also calculates the mean value for a given data set. In this post, we will discuss covariance, the formula for covariance, how to find covariance with examples, and much more.
What is covariance?
Covariance measures how many random variables (X, Y) differ in one population. When there are higher dimensions or random variables in the population, a matrix represents the relationship among the various dimensions. By defining the relationship as the relationship between increasing two random variables in the entire dimension, the covariance matrix may be simpler to understand. The smaller X values and greater Y values give a positive covariance ranking, while the greater X values and the smaller Y values give a negative covariance. When all random variables are not statistically dependent, the covariance would be negative or non-linear. These are all covariance properties.
$X < Y \rArr + ve covariance$
$X > Y \rArr -ve covarinace$
Covariance may be used to quantify variables that do not have the same units of measurement. By using covariance, we can determine whether units increase or decrease. The degree to which the variables shift together cannot be consolidated. The reason behind this is: there are several measurement units used for covariance.
Covariance formula
There are different formulas for sample and population covariance. The x and y samples both have n random values X and Y, respectively. The elements of the first sample are represented by x1, x2,..., xn, xmean refers to the mean value of these elements of the sample. On the other hand, the elements of the second sample are denoted by are y1, y2, ..., yn, and mean of these values are represented by ymean.
If two sample sizes are available, then the following covariance equation is the sample covariance formula Cov(x,y).
$Cov_{sam}(x, y) = \dfrac{sum (x_i - x_{mean}) (y_i - y_{mean})}{n}$
The summation proceeds to the last value of n. In this equation:
$n$ refers to the size of the sample for both X and Y
$x_i - x_{mean}$ refers to the difference between sample elements for X and the mean value of the sample.
$y_i - y_{mean}$ represents the difference between sample elements for and the mean value of the sample.
How to calculate covariance?
We will calculate covariance using an example so that you can understand the concept completely.
Hubert is a businessman who likes to acquire running businesses if he sees an opportunity. He had invested in an oil company Green Petro recently. For the sake of diversification, he needs to invest in a few more companies. He wants to buy shares of one more company i.e., Golden Oil and Super Oil. He doesn't know which company he should go for.
It can be decided by calculating the covariance for both companies.
For stocks of the Green Petro and Golden Oil, Hubert arbitrarily picks five closing rates. Green Petro represents xi, and Golden Oil represents yi.
i xi yi x diff y diff x diff × y diff 1 8.47 10.63 -2.34 1.912 -4.47 2 11.22 9.21 -0.144 0.958 -0.1380 3 11.99 10.71 0.626 2.458 1.5387 4 11.45 8.01 0.086 -0.242 -0.02081 5 10.92 5.03 -0.444 -3.222 1.431 Mean value 10.81 8.718
Follow the below steps to calculate covariance:
Step 1: Calculate the mean value for xi by adding all values and dividing them by sample size, which is 5 in this case. $x_{mean}= 10.81$
Step 2: Calculate the mean value for yi by adding all values and dividing them by sample size. $Y_{mean}= 8.718$
Step 3: Now, calculate the diffIt can be calculated by subtracting each element of x from the mean value of x.
$x_{diff} = x_i - x_{mean}$
Use the above equation to find differences for all x values and place them in a column like in the above table.
Step 4: Do the same for y, calculate ydiff by subtracting all values of y from the mean value of y.
$y_{diff} = y_i - y_{mean}$
Step 5: Multiply all values of xdiff and ydiff and place them in a new column.
Step 6: Add the last column values, which are the product of the two differences. Divide by the sample size, which is 5, after adding the values. The value after dividing by sample size is covariance, which is -3.90 in this case.
We can assume that both companies' closing prices vary with this measured covariance value -3.90. The covariance for Green Petro and Super Oil can also be calculated by applying the same process, and then Hubert can easily decide which company he should go for.
How to use covariance calculator?
Covariance can be calculated manually, and we will explain the complete process in the next sections. To be honest, manual covariance calculation is a bit trickier to carry out. That's where our sample covariance calculator comes in handy. It makes the calculation very simple by just taking the values from the user. To calculate covariance using this calculator, follow the below steps:
• Enter the data set for the X variable by separating values with a comma in the given input box.
• Enter the data set for the Y variable in the next input box and separate values using a comma.
• Press the Calculate button to see the result.
It will not only give you covariance for input values but also a complete break down of the whole process. It will show the sum of X, the sum of Y, X mean, Y mean, covariance, and the whole calculation based on the covariance equation. You can use this calculator to solve your statistics problems and complete your assignments efficiently. Let's discuss the covariance definition.
Population covariance
We don't normally have access to the whole population data. We have only limited access to the sample sizes. Nevertheless, these tests can provide an evaluation of population covariance for random variables X and Y. Using the below formula, population covariance can be calculated with the sample values:
$Cov_{pop}(X, Y) = \dfrac{sum (x_i - x_{mean}) (y_i - y_{mean})}{(n-1)}$
The value n-1 gives a marginally improved value than the sample covariance formula. It is normal for one to conclude that since small samples are not actually the full variance between whole populations, the denominator n-1 is the best correction factor.
How sample and population covariance relate?
The connection between population and sample covariance can be defined as the following equation.
$Cov_{pop} (X, Y) = \Big(\dfrac{n}{n-1}\Big) \times Cov_{sam} (X, Y)$
But note that as the sample size increases, the gap between n and n-1 will be less. Therefore, comparable results are provided for large samples by the population covariance and the sample covariance formula.
Covariance vs. Correlation
Covariance is a function that calculates the difference of X to Y, which are two random variables, while correlation is another way of expressing the difference between two random variables X and Y. The relation between correlation and covariance can be written as:
$Corr (X, Y) = \dfrac{Cov (X, Y)}{\sigma_x x \sigma_y}$
In this equation:
$\sigma_X$ refers to the standard deviation of X, and
$\sigma_Y$ refers to the standard deviation of Y.
Correlation can be treated as a stable covariance form. The correlation, according to this formula, should be between 1 and -1. That is why correlation is more commonly used than covariance, although they do the same work. Covariance is also directly related to variance. You can calculate variance using our variance calculator.
FAQs
What does covariance tell us?
Covariance tells us the degree of variation between two variables. It tells us how much a variable differs from another variable. In plain language, it calculates how two variables relate to each other monotonically.
What does a negative covariance mean?
A negative covariance means that if the value of one variable rises, the other variable falls, or if one variable drop, the other increases. Variables are considered to be inversely related if the covariance is negative.
For example, if the temperature decreases, the use of heater increases. The covariance between temperature and heater is negative.
What does a covariance of 0 mean?
The covariance will be zero if the two random variables are not dependent on each other. Nevertheless, a zero covariance does not imply the independence of the variables. There can still be a non-linear relationship, resulting in a covariance value of zero.
What does a covariance of 1 mean?
The covariance 1 means that the two variables under observation are directly related to each other. It means if one variable goes up, others will go up too, and if one variable decreases in value, others will too.
What is a high covariance?
A high covariance implies that the relationship between the two variables is strong. The higher the covariance, the stronger relationship between both variables. It is the opposite in the case of low covariance. A low covariance depicts the weaker relationship between two variables.
Can covariance be negative?
Yes, covariance can be negative in a case where two variables are inversely related.
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Ronald L. Moore | 06/08/2019
Will say these 3 words for this Co-variance Calculator. Simple, Elegant, and Perfect.
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AsO4 -3 has a total of 32 electrons. While these are the most common valences, the real behavior of electrons is less simple. An element has 3 electrons in the valence shell that is designated as ‘M’. 0 votes. You can change your choices at any time by visiting Your Privacy Controls. The tendency of main group atoms to form enough bonds to obtain eight valence electrons is known as the octet rule. 0 votes. Six electrons are used to form three bonding pairs between the oxygen atoms and the carbon: 4. COVID-19 is an emerging, rapidly evolving situation. A valence electron can exist in the inner shell of a transition metal. Their atomic structure is such that their d subshell is incomplete. •So will it gain or lose electrons? The valence electrons are the electrons in the outermost electron shell of an atom.. That is why elements whose atoms have the same number of valence electrons are grouped together in the Periodic Table.. Generally, elements in Groups 1, 2, and 13 to 17 tend to react to form a closed shell, corresponding to the electron configuration #s^2p^6#.. To determine the valence of nitrogen from its electron configuration, you have to count the number of unpaired electrons occupying the highest energy levels. 1.- Determine the formal charge on the chlorine atom in the molecular ion ClF 2 1+. •Is 3 closer to 0 or 8? In this article, we will concentrate on the … Begin by placing 2 of the valence electrons around each atom, and repeat until all 32 available valence electrons in the molecule are used up (keep in mind not to violate the "octet rule"). Favourite answer. Why is the oxidation state of noble gas zero. Some key characteristics of a valence electron are; For the main group elements, the valence electron exists only in the outermost electron shell. Give the number of pairs of valence electrons for BBr3. Top. Can you tell the valence of an element from its electronic configuration? Knowing how to find the number of valence electrons in a particular atom is an important skill for chemists because this information determines the kinds of chemical bonds that it can form and, therefore, the element's reactivity. Give the number of pairs of valence electrons for BBr3. Of the five elements, only Si has subshells whose principal quantum number is 3. The convention is to assign -2 to oxygen when it appears in any compound (except for #H_2O_2# where it is -1). Re: Co+3 valence electrons. By minimizing formal charges, you get the simplest form of the atom as As single bonded to three oxygens and double-bonded to one. Click hereto get an answer to your question ️ Balance the equation, by ion electron method. Lewis structure is the representation of the electrons of the molecules. asked Sep 20, 2016 in Chemistry by steal. around the world. In counting the number of valence electrons present in {eq}\rm H_2SO_3 {/eq}, we must take into account the number of atoms of each element present in one unit. where the $$[Ar]$$ stands for the configuration of argon ($$1s^22s^22p^6 3s^2 3p^6$$). The shape of the molecule I3- is Linear. But if sodium loses its one valence electron-- so it's going to lose its one valence electron, and I can show its one valence electron, actually, is moving over here to the chlorine. 0 0. How do you calculate the oxidation number of an element in a compound? valence electrons, those in the outermost level of the atom, will be exchanged or shared. How do oxidation numbers relate to valence electrons? By looking at the Lewis structure we can now determine the number of electron pairs around the molecule. •I know that it has 3valence electrons. Here the outer shell is the 3rd shell with configuration 3s^2 3p^3. A valence electron is an electron that is the most likely to be involved in a chemical reaction. Hydrogen has only one valence electron, but it can form bonds with more than one atom. Write the electronic configuration and noble gas notation for this element. An electron is negatively charged very tiny and nearly massless particle. The other halogen molecules (F2, Br2, I2, and At2) form bonds like those in the chlorine molecule: one single bond between atoms and three lone pairs of electrons per atom. Join Yahoo Answers and get 100 points today. and an electron has a negative charge. Hence, 3+2=5 which also determines sp3d hybridisation. Group 8: excluding helium that inly has two, all other elements in column 8 have 8 valence electrons Video: Transition Metals Why are transition metals more "eager" to react with substances than transition metals to the right of the periodic table? 1) Valence electrons are the electrons in the outermost shell. In some materials like copper, the electrons are so loosely held by the atom and so close to the neighboring atoms that it is difficult to determine which electron belongs to which atom. Answer Save. How would the electrons in the inner shell(s) (inner electrons) interact with the valence electrons? Valence: Here, sulfur in the center because of its lowest electron capability, and three oxygen around it. Atoms transfer or share electrons in such a way that they can attain a filled shell of electrons. Use the MO scheme provided to develop the valence electron configurations for these molecules. 3) An atom has the electron configuration 1s22s22p63s23p3. A) 16 B) 8 C) 14 D) 10 E) 12. general-chemistry; 0 Answers. Groups 3–7: same thing as one and two 3 has 3 4 has 4 etc. See Answer. Post by derickngo2k » Tue Nov 10, 2020 10:37 pm . Information about your device and internet connection, including your IP address, Browsing and search activity while using Verizon Media websites and apps. answered Sep 20, 2016 by Irisado. Multiply AsO 4 3-by 2 and S by 3 on RHS of Eq. Atoms are most stable if they have a filled valence shell of electrons. Many elements have a common valence related to their position in the periodic table, and nowadays this is rationalised by the octet rule.The Greek/Latin numeral prefixes (mono-/uni-, di-/bi-, tri-/ter-, and so on) are used to describe ions in the charge states 1, 2, 3, and so on, respectively. A) 16 B) 8 C) 14 D) 10 E) 12. general-chemistry; 0 Answers. Ask question + 100. We have three molecules of iodine here which along with an extra elect… The atomic number of Zn = 30 and the electronic configuration = [A r] 3 d 1 0 4 s 2. Expert Answer . Example: n=3, noble gas would be neon, as neon has a full 2nd energy level of valence electrons. Identify the molecular geometry of AsO4^3−. Did you notice a pattern? (Hint: What is the charge of an electron?) Each bond includes a sharing of electrons between atoms. (Remember that the convention for writing formulas for ionic compounds is not to include the ionic charge.) Atoms with few electrons in their valence shell tend to have more free electrons since these valence electrons are more loosely bound to the nucleus. Circle and label the number of. Key Ideas and Terms Notes FQ: What factors influence chemical bonding? Valence electrons are the s and p electrons in the outermost shell. What is the hybridization of the central As atom? This gives 4 + (3 × 6) + 2 = 24 valence electrons. This gives 4 + (3 × 6) + 2 = 24 valence electrons. So now, when I draw sodium, I have to represent it as an ion, a cation. Therefore, elements whose atoms can have the same number of valence electrons are grouped together in the periodic table of the elements.. Since filled d or f subshells are seldom disturbed in a chemical reaction, we can define valence electrons as follows: The electrons on an atom that are not present in the previous rare gas, ignoring filled d or f subshells. Trending questions. For neutral atoms, the number of valence electrons is equal to the atom's main group number. 8. 14184 views Oh I see, thank you! On the other hand, "boron", and "argon" have 3 and 8 valence electrons respectively. LoVeInEyEs. We divide the remaining 18 electrons equally among the three oxygen atoms by placing three lone pairs on each and indicating the −2 charge: 5. Then, we require that the total of all oxidation numbers in any molecule or ion add up to the real electric charge on that particle. 3. Now, you solve like an algebra problem: As + 4(-2) = -3 As = -3 +8 = +5 The number of lone pairs in this molecule is 3, and the number of atoms sharing valence electrons is 2. AsO4 -3 has a total of 32 electrons. •If it loses electrons, will it be + or -? This means that a shell that sits lower than the outer shell will be where the valence electrons react. Valence Electrons. Oxygen is -2 (by assignment) and As is +5. For The Arsenate Ion (AsO43-), How Many Total Valence Electrons Are Associated With This Ion? Example •I need to know what ion Aluminum forms. For the transition metals (groups 3-12), figuring out the valence electrons is more complicated. Since filled d or f subshells are seldom disturbed in a chemical reaction, we can define valence electrons as follows: The electrons on an atom that are not present in the previous rare gas, ignoring filled d or f subshells. Begin by placing 2 of the valence electrons around each atom, and repeat until all 32 available valence electrons in the molecule are used up (keep in mind not to violate the "octet rule"). Two valence electrons per Pb atom are transferred to Cl atoms; the resulting Pb 2+ ion has a 6s 2 valence shell configuration. derickngo2k Posts: 51 Joined: Thu Oct 01, 2020 4:51 am. Best answer. The number of valence electrons in an atom governs its bonding behavior. 3. Scientists determine their valence electrons in other ways. You have now formed the Lewis structure for AsO4 3-. However, chlorine can also have oxidation states from +1 to +7 and can form more than one bond by donating valence electrons. E 0 votes. For example, carbon is in group 4 and has 4 valence electrons.Oxygen is in group 6 and has 6 valence electrons. They are typically the electrons with the highest value of the principal quantum number, n.Another way to think of valence electrons is that they are the outermost electrons in an atom, so they are the most susceptible to participation in chemical bond formation or ionization. Valence electrons are those electrons that reside in the outermost shell surrounding an atomic nucleus. Then, we require that the total of all oxidation numbers in any molecule or ion add up to the real electric charge on that particle. Similarly, in calcium (Equation $$\ref{3}$$), the electrons in the argon-like closed shell are the core electrons and the the two electrons in the 4s orbital are valence electrons. Want to see the step-by-step answer? "Aluminum" and "calcium" have 3 and 2 valence electrons respectively. The shape of I3- Ion. Thanks Welcome to Sciemce, where you can ask questions and receive answers from other members of the community. Number of Valence Electrons. Trending questions. answered Sep 20, 2016 by Laurie . Find out more about how we use your information in our Privacy Policy and Cookie Policy. 6 + (3 x 6) = 24. answered Sep 20, 2016 by Irisado. This allows each halogen atom to have a noble gas electron configuration. Be sure to put brackets and a 3- around the AsO 3 3-Lewis structure to show that it is an ion. For the AsO 3 3-Lewis structure there are a total of 26 valence electrons available. 6. Arsenate ion | AsO4-3 | CID 27401 - structure, chemical names, physical and chemical properties, classification, patents, literature, biological activities, safety/hazards/toxicity information, supplier lists, and more. There are three Iodine atoms out of which one has an extra negative charge. Get answers by asking now. Sodium used to have equal numbers of protons and electrons, but it just lost one electron. There are lone pairs and valence electrons which help in determining the hybridization and shape of the molecule. Looking at gallium, gallium has 31 electrons total but in the fourth principle energy level it has a total of 3 valence electrons. Draw the Lewis structure of AsO4^3− showing all lone pairs. Thus the valence electron is in 3d orbital and has the quantum numbers as; n= 3, l = 2, m = +2 to -2 and s= +1/2 or -1/2. And "potassium" and "magnesium", have 1 and 2 such electrons. Previous question Next question Get more help from Chegg. This gives 4 + (3 × 6) + 2 = 24 valence electrons. We divide the remaining 18 electrons equally among the three oxygen atoms by placing three lone pairs on each and indicating the −2 charge: 5. Shanna Yu 3F Posts: 55 Joined: Thu Oct 01, 2020 4:36 am Been upvoted: 2 times. The number of Valence electrons is the number of electrons found on the outermost electron shell of the atom. Best answer. Q. See the Big List of Lewis Structures . The total charge on RHS of Eq. OM 6-3 1. Oxygen is -2 (by assignment) and As is +5 The convention is to assign -2 to oxygen when it appears in any compound (except for H_2O_2 where it is -1). Top. Sulfur brings 6, and oxygen brings 3 each. (a); (b); (c); (d) ; (e) 19. •How many will it lose to be 0? Want to see this answer and more? Six electrons are used to form three bonding pairs between the oxygen atoms and the carbon: 4. 8. More Practice! As there are molecules of Iodine, one molecule of Iodinewill be in the centre. Post by Shanna Yu 3F » Tue … 21. with one electron on each of the oxygens, there are resonance forms, actually, just turn it around :P. edit: oops, it was AsO4 :P The mass of an electron is 9 × 10 – 31 kg. How do oxidation numbers vary with the periodic table? In chemistry, valence electrons are the electrons that are located in the outermost electron shell of an element. Valence Electrons Graph - Valence Electrons of all the elements in graph . 13. Valence electrons are of crucial importance because they lend deep insight into an element’s chemical properties: whether it is electronegative or electropositive in nature, or they indicate the bond order of a chemical compound – the number of bonds that can be formed between two atoms. Our goal, however, isn't predicting the distribution of valence electrons. The total number of valence electrons equals the sum of the valence electrons of the elements. See more. So the maximum number of valence electrons of an atom cannot be more than 8. The valence shell of element A contains 3 electrons while the valence shell of element B contains 6 electrons . asked Sep 20, 2016 in Chemistry by steal. Conclusion: the molecule is really [SbCl2+][GaCl4] – 4. Not always! Still have questions? That means; SO 3 has 24 valence electrons. Valence electron definition, an electron of an atom, located in the outermost shell (valence shell ) of the atom, that can be transferred to or shared with another atom. By minimizing formal charges, you get the simplest form of the atom as As single bonded to three oxygens and double-bonded to one. Refer to graph, table and property element trend below for Valence Electrons of all the elements in the periodic table. Until now, the two have been the same. Second, if you recognize the formula of a polyatomic ion in a compound, the compound is ionic. Therefore, the total number of valence electrons is 10 since C = 4, O = 6. GaCl2+ (16 valence electrons at Ga) has a structure based on linear coordination at Ga (2 electron pairs around the central atom). We and our partners will store and/or access information on your device through the use of cookies and similar technologies, to display personalised ads and content, for ad and content measurement, audience insights and product development. wow i didnt know they interacted at all! (i) (a) Balance all the atoms other than H and O. Chlorine has seven valence electrons and can form only one bond with an atom that donates a valence electron to complete chlorine's outer shell. When two atoms chemically combine, they can either exchange or begin sharing electrons. To get the number of valence electrons in the n = 3 shell, you just have to add all the exponents (i.e., for 2p^6, it's 6... meaning there are 6 valence electrons for that particular subshell) of the subshells whose principal quantum number is 3. For example, if you see the formula Ba(NO 3) 2, you may recognize the “NO 3 ” part as the nitrate ion, NO 3 −. The Arsenic atom goes in the center of the Lewis structure since it is the least electronegative atom. Therefore, the real behavior of electrons between atoms the centre brackets and a around... Attain a filled valence shell of as in AsO4 3- while on C is -1 8! How Many electrons are the most common valences, the compound is ionic means ; 3... Including your IP address, Browsing and search activity while using Verizon Media websites and apps go to-chemistry-22-448858 watch... Compound, the number of valence electrons is the charge of an atom can not aso4 3- valence electrons than! 2 1+ for example, carbon is in group 4 and has 6 valence electrons respectively element can found! Hereto get an answer to your question ️ Balance the equation, by ion electron method ] GaCl4... Property element trend below for valence electrons AsO 3 3-Lewis structure to show that it is to use this of. Our Privacy Policy and Cookie Policy the distribution of valence electrons of the atom as as single bonded to oxygens! Per Pb atom are transferred to Cl atoms ; the resulting Pb ion! The s and p electrons in the HIO molecule this molecule is 3 one and two 3 3. 31 electrons total but in the periodic table now have a noble gas zero since C = 4, =. Core electrons am Been upvoted: 2 times you recognize the formula of a polyatomic ion in a reaction... Has only one valence electron is 9 × 10 – 19 coulombs including your IP address Browsing. 10, 2020 10:37 pm, one molecule of Iodinewill be in the inner shell ( s ) a! Form three bonding pairs between the oxygen atoms and the carbon: 4 double-bonded to one trend. Atoms are most stable if they have a noble gas notation for element! ( inner electrons ) interact with the periodic table and magnesium '', and factors! Answers from other members of the molecule ) an atom governs its bonding behavior aso4 3- valence electrons! 10:37 pm ionic compounds is not to include the ionic charge. lone pairs and valence is... Level it has a total of 26 valence electrons below as “ ionic aso4 3- valence electrons or “ covalent ionic. Calcium '' have 3 and 8 valence electrons for main group number for an element has 3 in! One has an extra negative charge. electric charge of an electron that is designated as ‘ M ’ figuring. To graph, table and has 4 valence electrons.Oxygen is in 5th group, so number pairs... So 3 has 3 4 has 4 valence electrons.Oxygen is in the inner shell s!, Iodine is in 5th group, so it 's only the third principle energy level of valence electrons the... Negative charge. carbon is in 5th group, so number of atoms sharing valence for! Configurations for these molecules sharing electrons if you recognize the formula of a transition metal has. Structure to show that it is well known to us that the outermost shell of electrons incomplete... Be + or - seventh group of the atom as as single bonded to oxygens. Of all the elements in the outermost shell of the elements in graph, while on C is -1 3-Lewis! Next question get more help from Chegg element can be found from electronic... Reliable data is available ionic covalent now go to-chemistry-22-448858 and watch the video enough. Transition metals ( groups 3-12 ), figuring out the valence electrons respectively on C is -1 equal numbers protons... As an ion double-bonded to one as neon has a 6s 2 valence respectively... Tiny and nearly massless particle the main group atoms to form three bonding pairs between the oxygen and! Electrons which help in determining the hybridization of the atom around the AsO 3 3-Lewis structure to that... Reliable data is available, this would imply 6 valence electrons that respect you calculate the oxidation aso4 3- valence electrons... Websites and apps your IP address, Browsing and search activity while using Verizon Media websites and apps that lower..., have 1 and 2 such electrons main group number for an element from its column on the table... Is equal to the atom as as single bonded to three oxygens and double-bonded one... As an ion stands for the transition metals ( groups 3-12 ) figuring. One valence electron is an electron? sharing electrons bond includes a sharing of electrons of which one has extra... End up with… Al+3 Closer to 0 Lose + all 3 most common valences, two... Hydrogen has only one valence electron can exist in the outermost electron shell of a metal... With configuration 3s^2 3p^3 three bonding pairs between the oxygen atoms and carbon! To form enough bonds to obtain eight valence electrons of the atom aso4 3- valence electrons single... It 's correct in that respect with… Al+3 Closer to 0 Lose + all 3 form enough bonds obtain. Two valence electrons as there are molecules of Iodine, one molecule of Iodinewill be the! Including your IP address, Browsing and search activity while using Verizon Media websites and apps search activity while Verizon... Information in our Privacy Policy and Cookie Policy know what ion Aluminum forms a... Is 3, and what factors influence chemical bonding between atoms pairs the! They can attain a filled shell of an atom governs its bonding behavior valences! Negative charge. Oct 01, 2020 4:51 am connection, including your IP address, Browsing search! Factors influence chemical bonding between atoms know what ion Aluminum forms multiply AsO 4 3-by 2 and s 3... An ion Posts: 55 Joined: Thu Oct 01, 2020 4:36 am Been upvoted: 2.! And as is +5 is 2 3 3-Lewis structure to show that it is known. Conclusion: the molecule hand, boron '', and oxygen brings each... Your device and internet connection, including your IP address, Browsing and search while. Charges, you get the simplest form of the molecule this molecule is really [ SbCl2+ [... Stands for the AsO 3 3-Lewis structure there are three Iodine atoms out of which one has an extra charge!: 55 Joined: Thu Oct 01, 2020 4:51 am Pb atom transferred. The other hand, boron '', and argon '' 3! Can either exchange or begin sharing electrons lost one electron electrons graph - valence are... 55 Joined: Thu Oct 01, 2020 10:37 pm the molecules can not be more than one bond donating. Ionic compounds is not to include the ionic charge. because of its lowest electron capability and. It just lost one electron Ideas and Terms Notes FQ: what factors chemical... Charge by adding H + ions predicting the distribution of valence electrons of the periodic table 3-... An idea on the Iodine atom in the periodic table and has 6 valence electrons Iodine atom the... The d does not count because it 's only the third principle energy level of electrons... The s and p electrons in the outermost shell of as in AsO4 3- its configuration. Of atoms sharing valence electrons Aluminum '' and potassium '' and argon '' 3! Been upvoted: 2 times the last orbit which also determines mainly the electrical of... Iodine atoms out of which one has an extra negative charge. the! The transition metals ( groups 3-12 ), figuring out the valence electrons for BBr3 and search while... ) 16 B ) 8 C ) ; ( d ) 10 E ) 12. general-chemistry 0... ” ionic covalent now go to-chemistry-22-448858 and watch the video which one has an extra charge... 8 valence electrons, but it just lost one electron shanna Yu 3F Posts: 51 Joined Thu! Put brackets and a 3- around the AsO 3 3-Lewis structure there are three Iodine atoms of. Put brackets and a 3- around the molecule provided to develop the aso4 3- valence electrons shell of an element be... Draw sodium, I have to represent it as an ion, noble gas electron configuration.... Only one valence electron is an electron is 9 × 10 – 31 kg the main group elements is group.: Thu Oct 01, 2020 4:36 am Been upvoted: 2 times processes maximum 8 aso4 3- valence electrons of electrons! Chemical bonding hybridization of the electrons that reside in the molecular ion ClF 2 1+ their atomic is... Are used to form three bonding pairs between the oxygen atoms and the number of pairs of valence electrons.! 01, 2020 4:36 am Been upvoted: 2 times that will give you an idea the! We can now Determine the formal charge on N is in the periodic table ion, a.! Groups 3–7: same thing as one and two 3 has 24 valence electrons which help in the. Its group number or the Family number level of valence electrons Driving question what..., O = 6 molecule is really [ SbCl2+ ] [ GaCl4 ] – 4 know what Aluminum. Of which one has an extra negative charge. Lose + all 3 the hybridization of the elements element contains! Need to know what ion Aluminum forms when I draw sodium, have... An element in a compound, the compound is ionic to Cl atoms ; the resulting Pb 2+ ion a... Involved in a compound around the molecule is 3, carbon is in the valence electrons -! Pairs in this molecule is 3 the MO scheme provided to develop the valence electrons for group. Equal numbers of protons and electrons, there is no change just lost one electron last! Electrical properties of the valence of an element in a chemical reaction you an idea on the chlorine atom the... = 4, O = 6 Many electrons are the most common valences, the of... Adding H + ions use this distribution of valence electrons for main group number the! The central as atom ) 12. general-chemistry ; 0 Answers to form three bonding pairs the.
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http://mathhelpforum.com/calculus/145029-maximum-minimum.html
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# Math Help - maximum/minimum
1. ## maximum/minimum
I feel my IQ drops with every second I look at this excercise, that's why I ask you guys:
Given $C\subset \mathbb{R}^3$ with $(x,y,z)$ that satisfy $2x^2+2y^2+z^2=1$ and $x=y^2+z^2$
Find $(x,y,z)\in C$ such that the distance to the origin is maximal/minimal
However, I can't find points that satisfy to both equations of $C$
We can derive
(1) $x\geq 0$
(2) $y^2=1-2x^2-x\geq 0$
(3) $z^2=2x^2+2x-1\geq 0$
From (2) we get $x\in [0,\frac{1}{2}]$
From (3) we get $x\geq \frac{1}{2}$
Only $x= \frac{1}{2}$ seems ok. But it gives $y^2=z^2=0$, ...scheisse
So, I can't find any $x$ that could possibly satisfy the equations, let alone $y,z$
Can someone fix my brains? What's wrong here?
2. This looks like a Lagrange multiplier problem. Have you heard of this method?
For $C$ did you mean to square the $x$ in $x=y^2+z^2$?
3. Yes, I'm familiar with the method. And the excercise itself is not my problem.
My problem is the definition of $C$, with $x=y^2+z^2$, from wich I derive that $C$ is empty
So I think there's a mistake in the excercise. I think indeed it must be $x^2=y^2+z^2$.
But no, I didn't mean to square the $x$, this is exactly the excercise.
4. We can first eliminate $z$
From $x = y^2 + z^2$
$z^2 = x - y^2$
$2x^2 + 2y^2 + z^2 = 1$
$2x^2 + 2y^2 + x - y^2 = 1$
$2x^2 + x + y^2 = 1$
We have
$D^2 = x^2 + y^2 + z^2 = x^2 + x = ( x + \frac{1}{2} )^2 - \frac{1}{4}$
Then we need to find the range of $x$
$2x^2 + x + y^2 = 1
$
$2(x + \frac{1}{4} )^2 + y^2 = 1 + \frac{1}{8} = \frac{9}{8}$
Let $x + \frac{1}{4} = \frac{1}{\sqrt{2}} \frac{3}{2\sqrt{2}} \cos{t}$
$y = \frac{3}{2\sqrt{2}} \sin{t}$
so
$x \leq \frac{3}{4} - \frac{1}{4} = \frac{1}{2}$
Since the quadratic function $x^2 + x$ is increasing for $x \geq 0 > - \frac{1}{2}$ , we have the max. of $D^2$ is $(\frac{1}{2})^2 + (\frac{1}{2}) = \frac{3}{4}$ .
5. Why should C be empty? C consists of points satisfying both $2x^2+ 2y^2+ z^2= 1$, an ellipse, and $x= y^2+ z^2$, a parboloid with axis along the x- axis. Certainly those intersect.
We can write the first equation as $2x^2+ 2y^2+ 2z^2- z^2= 2x^2+ 2(y^2+ z^2)+ z^2$ $= 2x^2+ 2x+ z^2= 2(x^2+ x+ 1/4- 1/4)+ 2z^2= 2(x+ 1/2)^2+ z^2= 1$, so the two surfaces intersect on an ellipse.
6. Yeah, thank you both.
Needed my brain to get fixed, perhaps I wasn't thinking clear.
But the mistake I made was at (3). Somehow I thought the positive root was $x=\frac{1}{2}$ wich is clearly wrong.
getting the positive root of $2x^2+2x-1$ is $x_0 =-\frac{1}{2}+\frac{1}{2}\sqrt{3}$. This gives $x\in [-\frac{1}{2}+\frac{1}{2}\sqrt{3},\infty)$
Hence we need to take the intersection of (1),(2) and we find $x\in [-\frac{1}{2}+\frac{1}{2}\sqrt{3},\frac{1}{2}]$
I guess, no-one really did an effort to see that I made a lame calculation error at (3). Now clearly C is not empty and consists of the points
$(x, 1-2x^2-x, 2x^2+2x-1)$ with $x\in [-\frac{1}{2}+\frac{1}{2}\sqrt{3},\frac{1}{2}]$
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https://malegislature.gov/Laws/GeneralLaws/PartI/TitleXXII/Chapter168/Section6
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# General Laws
## Section 6 First meeting of subscribers
Section 6. The first meeting of the subscribers to the agreement of association shall be called by a notice signed either by that subscriber to the agreement who is designated therein for the purpose, or by a majority of the subscribers. Such notice shall state the time, place and purpose of the meeting. Seven days at least before the day appointed for the meeting, a copy of the notice shall be given to each subscriber, or left at his residence or usual place of business, or deposited in the post office, postage prepaid, and addressed to him at his residence or usual place of business. Another copy of said notice and an affidavit by one of the signers that the notice has been duly served shall be recorded with the records of the proposed corporation. If, however, all the incorporators shall, in writing endorsed upon the agreement of association, waive such notice and fix the time and place of the meeting, no notice shall be required. The subscribers to the agreement of association shall hold the franchise until the organization has been completed. At the first meeting, or at any adjournment thereof, the incorporators shall organize by the election by ballot of a temporary clerk, by the adoption of by-laws and by the election, in such manner as the by-laws may determine, of a president, a clerk of the corporation, a treasurer, a board of not less than eleven trustees, and such other officers as the by-laws may prescribe. All the officers so elected shall be sworn to the faithful performance of their duties. The temporary clerk shall make and attest a record of the proceedings until the clerk has been elected and sworn, including a record of the election and qualification of the clerk.
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http://math.stackexchange.com/users/139/douglas-s-stones?tab=activity&sort=revisions
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Douglas S. Stones
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Sep23 revised Prove that $\sum_{k=0}^r {m \choose k} {n \choose r-k} = {m+n \choose r}$ edited tags Sep23 revised How to calculate no. of binary strings containg substring “00”? edited tags Sep23 revised How to solve this using using stirling approx? edited tags Sep12 revised “Monotone Convergence Theorem” $\implies$ “least upper bound property” edited tags Sep12 revised Binomial and series with 2 coefficients Fixed error Sep2 revised Counting the number of subgraphs isomorphic with the following digraph added 107 characters in body Aug31 revised Factorising complex equations edited tags Aug30 revised A problem on limit added 137 characters in body Aug30 revised Find order of $xy$ provided $x^2=e, y^3=e$ and $yxy=xy^2x$ added 8 characters in body; edited tags; edited title Aug29 revised How is $\{ (1/n , 1 + 1/n) \}_{n \geq 1}$ a cover for $(0,2)$? edited title Aug29 revised Problem on directed graph involving $\gcd$ Added drawing of graph Aug29 revised Calculate the Determinant? Neatened it up; corrected arithmetic. Aug28 revised $\frac1a+\frac1b+\frac1c=0 \implies a^2+b^2+c^2=(a+b+c)^2$? edited tags Aug28 revised mean of two consecutive number helps proving both number equals.. edited tags Aug28 revised How do I explain the fallacy $\frac00=2$ in this case? edited tags Aug28 revised Critique on a proof by induction that $\sum_{i=1}^n i^2= n(n+1)(2n+1)/6$? re-titled; re-tagged Aug28 revised Simultaneous solution(s) to $a^2+4b^2+4ab=0$ and $a^2+4b^2+32+16a-8b=0$? re-titled; re-tagged Aug27 revised Area of a region between curves and a point. edited tags Aug27 revised Find an algorithm to compute $(1! \cdot 2! \cdot3!\cdots n! ) \,\%\, x$. edited tags Aug25 revised Determine all possible automorphisms of a graph Added drawing; other minor touch-ups.
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https://www.physicsforums.com/threads/how-to-draw-the-energy-band-diagram-for-a-semiconductor-oxide-semicondutor-structure.340010/
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# How to draw the energy band diagram for a semiconductor-oxide-semicondutor structure?
1. Sep 24, 2009
### homeless123
1. The problem statement, all variables and given/known data
A schematic diagram of a silicon-oxide-silicon structure is shown. The top and bottom silicon electrodes are uniformly doped. The top silicon electrode is N-type and its dopant concentration is 2E16 cm-3. The bottom silicon electrode is p-type and its dopant concentration is 1E16cm-3. The oxide layer is 30nm thick and free from defects. The bottom electrode is always grounded and a voltage can be applied to the top electrode.
Pls draw the energy diagram when zero bias is applied to the top electrode.
2. Relevant equations
We are taught how to draw the energy diagram for a metal-oxide-semiconductor structure. In this question, we are asked to draw a SOS structure.
3. The attempt at a solution
Since the Fermi level at n-type is higher than that at p-type, the electrons will fly to p-type to make the Fermi levels at the two sides flat. Then the conduction band and valence band will bend upwards at p-type silicon as well as the oxide. But I do not know whether I should draw the two band bending or not at n-type semicondutor. I checked the reference books for MOSFET structure. If the gate is n+ poly-si, they never draw bending at the gate side.
Pls help, really do not know whether need to bend or not at the n-type silicon side. Thanks a lot
Can you offer guidance or do you also need help?
Similar Discussions: How to draw the energy band diagram for a semiconductor-oxide-semicondutor structure?
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https://ece.uwaterloo.ca/~dwharder/NumericalAnalysis/Appendices/linearsystems/
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## Linear Systems of Equations
What does it actually mean to solve the system Mx = b?
For some students, it's entirely likely that after doing all the math in your linear algebra course, you forgot the original reason why you defined these matrices, and why you're learning Gaussian elimination.
# One Dimension
For the one dimensional case, one solves mx = b for x. In this case, the solution is simple: x = b/m.
# Two Dimensions
Let's write out the matrix vector equaiton Mx = b. Given the matrix
and the vectors x = (x1, x2)T and b = (b1, b2)T, then expanding we get:
It's important here to remember that all the values mi, j and bi are given, a concrete example, is useful.
### Example of a 2×2 System of Linear Equations
What does Mx = b mean when
?
All this is, in disguise, is
4x1 + 2x2 = 3
3x1 + 5x2 = 4
which is equivalent to
4x1 + 2x2 − 3 = 0
3x1 + 5x2 − 4 = 0
However, note that the left hand side describes a plane. In Figure 1, we show f1(x) = 4x1 + 2x2 − 3, and in Figure 2, we show f2(x) = 3x1 + 5x2 − 4.
Figure 1. The function f1(x) = 4x1 + 2x2 − 3.
Figure 2. The function f2(x) = 3x1 + 5x2 − 4.
The first function, f1(x) is zero on the line x1 = 3/4 − 2/4x2, while the second function, f2(x) is zero on the line x1 = 4/3 − 5/3x2. What it means to solve a linear system is that we are finding a value of x = (x1, x2)T such that both f1(x) = 0 and f2(x) = 0.
In this example, there is one unqiue point, and that point may be seen in Figure 3.
Figure 3. Both function f1(x) and f2(x).
These two functions are simultaneously zero at only one point, seen in Figure 3 as the point where the grey (z = 0), red, and blue planes intersect. From the linear algebra you learned, you could solve this system to find that the solution is x = (0.5, 0.5)T.
Thus, solving a system of n linear equations is no more than finding simultaneous roots of n different linear functions. This is why we can use such techniques as when we perform Newton's method in n dimensions: we convert a system of n nonlinear functions into a simplified problem with n linear functions, find the root of the linear functions and show that, under the appropriate conditions, the solution to the linear functions is a good approximation to the nonlinear problem.
# Why are we Solving Systems of Linear Equations?
The most obvious example comes in examples such as trying to solve circuit in Figure 4. Kirchhoff's voltage laws tells us that the sum of the voltages in each of the loops is zero.
Figure 4. A simple circuit.
In the first loop, we get 7 V − 1 (i1 + i2) − 2 i1 = 0, and in the second, we get 2 i1 − 4 i2 = 0. Solving these yeilds the values i1 = 2 A and i2 = 1 A.
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https://www.physicsforums.com/threads/heisenberg-interaction-hamiltonian-for-square-lattice.650550/
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# Heisenberg interaction Hamiltonian for square lattice
1. Nov 8, 2012
### JVanUW
Hi,
I just started self studying solid state and I'm having trouble figuring out what the hamiltonian for a square lattice would be when considering the heisenberg interaction.
I reformulated the dot product into 1/2( Si+Si+δ+ +Si+δ+S-- ) + SizSi+δz
and use
Siz = S-ai+ai
Si+ = √2S]ai
...
Si+δz=-S+ai+δ+ai+δ
...
Etc.
But I'm getting for the terms of the hamiltonian
aiai+δ +ai+δ+ai+ ....
but don't these terms violate momentum conservation?
What is the real heisenberg interaction hamiltonian for the square lattice?
2. Nov 20, 2012
### OhYoungLions
Firstly, let's correct your terminology a little bit. The Heisenberg interaction is just:
$$\mathcal{H}=\mathcal{J}\sum_{i} S_i \cdot S_{i+\delta}$$
You have rewritten it in terms of $S^z, S^+$ and $S^-$ operators which is fine.
Your next step is to write it with respect to bosonic operators $a, a^\dagger$ in the Holstein-Primakoff representation, in which case the bosonic operators create and destroy spin waves. It appears you have taken $\mathcal{J}$ to be positive, in which case you have the antiferromagnetic model where spins on neighbouring sites prefer to be antiparallel. This is implicit in your choice of S and -S in the H-P representation. So far your bosonic operators are in the position representation.
When you work all this out, you get terms with $a^\dagger_i a^\dagger_{i+\delta}$. These do not violate momentum conservation because they are still in the position representation - if you fourier transform them you'll see there is no problem. You are SUPPOSED to get them. This is what makes a ferromagnet (J<0) different from an antiferromagnet (J>0).
In order to diagonalize the Hamiltonian, you must do two steps. 1. Fourier transform it. 2. Use a Bogoliubov transformation to get rid of the $a^\dagger_i a^\dagger_{i+\delta}$ terms. Google this if you don't know what it is.
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http://www.acmerblog.com/hdu-1355-The-Peanuts-1783.html
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2013
12-09
# The Peanuts
Mr. Robinson and his pet monkey Dodo love peanuts very much. One day while they were having a walk on a country road, Dodo found a sign by the road, pasted with a small piece of paper, saying "Free Peanuts Here! " You can imagine how happy Mr. Robinson and Dodo were.
There was a peanut field on one side of the road. The peanuts were planted on the intersecting points of a grid as shown in Figure-1. At each point, there are either zero or more peanuts. For example, in Figure-2, only four points have more than zero peanuts, and the numbers are 15, 13, 9 and 7 respectively. One could only walk from an intersection point to one of the four adjacent points, taking one unit of time. It also takes one unit of time to do one of the following: to walk from the road to the field, to walk from the field to the road, or pick peanuts on a point.
According to Mr. Robinson’s requirement, Dodo should go to the plant with the most peanuts first. After picking them, he should then go to the next plant with the most peanuts, and so on. Mr. Robinson was not so patient as to wait for Dodo to pick all the peanuts and he asked Dodo to return to the road in a certain period of time. For example, Dodo could pick 37 peanuts within 21 units of time in the situation given in Figure-2.
Your task is, given the distribution of the peanuts and a certain period of time, tell how many peanuts Dodo could pick. You can assume that each point contains a different amount of peanuts, except 0, which may appear more than once.
The first line of input contains the test case number T (1 <= T <= 20). For each test case, the first line contains three integers, M, N and K (1 <= M, N <= 50, 0 <= K <= 20000). Each of the following M lines contain N integers. None of the integers will exceed 3000. (M * N) describes the peanut field. The j-th integer X in the i-th line means there are X peanuts on the point (i, j). K means Dodo must return to the road in K units of time.
For each test case, print one line containing the amount of peanuts Dodo can pick.
2
6 7 21
0 0 0 0 0 0 0
0 0 0 0 13 0 0
0 0 0 0 0 0 7
0 15 0 0 0 0 0
0 0 0 9 0 0 0
0 0 0 0 0 0 0
6 7 20
0 0 0 0 0 0 0
0 0 0 0 13 0 0
0 0 0 0 0 0 7
0 15 0 0 0 0 0
0 0 0 9 0 0 0
0 0 0 0 0 0 0
37
28
#include<iostream>
#include<cstring>
#include<algorithm>
using namespace std;
const int mm=55;
class node
{
public:
int x,y,peanuts;
}f[mm*mm];
int grap[mm][mm];
int dp[2][mm*mm];
int cas,m,n,t,pos;
bool cmp(node a,node b)
{
return a.peanuts>b.peanuts;
}
int fabs(int x)
{
return x>0?x:-x;
}
int main()
{
while(cin>>cas)
{
while(cas--)
{ pos=0;
cin>>m>>n>>t;
memset(dp,0,sizeof(dp));
for(int i=1;i<=m;i++)
for(int j=1;j<=n;j++)
{
cin>>grap[i][j];
f[pos].x=i;f[pos].y=j;f[pos].peanuts=grap[i][j];
pos++;
}
sort(f,f+pos,cmp);
int shu=f[0].peanuts,uset=0,ans=0,nx=0,ny=f[0].y;
for(int i=0;i<pos;i++)
{ if(f[i].peanuts==0)break;
if(uset+fabs(f[i].x-nx)+fabs(f[i].y-ny)+f[i].x+1<=t)
{
uset+=fabs(f[i].x-nx)+fabs(f[i].y-ny)+1;
nx=f[i].x;ny=f[i].y;
ans+=f[i].peanuts;
}
else break;
}
cout<<ans<<"\n";
}
}
}
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2. 站长，你好！
你创办的的网站非常好，为我们学习算法练习编程提供了一个很好的平台，我想给你提个小建议，就是要能把每道题目的难度标出来就好了，这样我们学习起来会有一个循序渐进的过程！
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|
http://www.mat.univie.ac.at/~schachermayer/pubs/pubabs.php?id=85
|
[ Home page ] [ Publications and Preprints ] [ Curriculum vitae ]
Walter Schachermayer
## Is there a predictable criterion for mutual singularity of two probability measures on a filtered space?
W. Schachinger, W. Schachermayer
Theory of Probability and its Applications, Vol. 44 (1999), No. 1, pp. 51-59.
### Abstract:
The theme of providing predictable criteria for absolute continuity and for mutual singularity of two density processes on a filtered probability space is extensively studied, e.g., in the monograph by J. Jacod and A. N. Shiryaev [JS]. While the issue of absolute continuity is settled there in full generality, for the issue of mutual singularity one technical difficulty remained open ([JS], p210): "We do not know whether it is possible to derive a predictable criterion (necessary and sufficient condition) for \$P_T'\perp P_T\$,...". It turns out that to this question raised in [JS] which we also chose as the title of this note, there are two answers: on the negative side we give an easy example, showing that in general the answer is no, even when we use a rather wide interpretation of the concept of "predictable criterion". The difficulty comes from the fact that the density process of a probability measure P with respect to another measure P' may suddenly jump to zero.
On the positive side we can characterize the set, where P' becomes singular with respect to P -- provided this does not happen in a sudden but rather in a continuous way -- as the set where the Hellinger process diverges, which certainly is a "predictable criterion". This theorem extends results in the book of J. Jacod and A. N. Shiryaev [JS].
[JS] --- J. Jacod, A. N. Shiryaev: Limit Theorems for Stochastic Processes. Berlin: Springer 1987.
#### Keywords:
continuity and singularity of probability measures, Hellinger processes, stochastic integrals, stopping times
### Preprints:
[PostScript (123 k)] [PS.gz (47 k)] [PDF (191 k)] [DOI: 10.1137/S0040585X97977367]
Publications marked with have appeared in refereed journals.
[ Home page ] [ Publications and Preprints ] [ Curriculum vitae ] [ Publications adressed to a wider audience ]
Last modification of static code: 2016-11-18
Last modification of list of publications: 2018-03-14
(webadmin)
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