Blender black screen animation
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Unity-like Dashboard for Gnome fallback? Is there any way I can run the Unity dashboard (or something similar, like Bolt for Gnome 3) in Gnome Fallback? Determine $\text{Aut}(S)$ where $S = \mathbb{Q}[x]/(x^2)$ Here's the problem: if $S = \mathbb{Q}[x]/(x^2)$, compute the group  of automorphisms $\mbox{Aut}(S)$.   First off, I have the solution and I know it's isomorphic to the multiplicative group $\mathbb{Q}\backslash\{0\}$, so I'm trying to understand it. It uses what is called the substitution principle and the fact that the restriction of any endomorphism $\phi: \mathbb{Q}[x]\to \mathbb{Q}[x]$ to $\mathbb{Q}$ is the identity. It says that these two facts implies that the endomorphisms of $\mathbb{Q}[x]$ are in 1-1 correspondence with $h \in \mathbb{Q}[x]$, where the endomorphism corresponding to $h$ is $\phi_h : \mathbb{Q}[x] \to \mathbb{Q}[x]$ given by $\phi_h(f) = f(h)$ for $f \in \mathbb{Q}[x]$. I guess I just don't understand how it applied the substitution principle? It's probably obvious, but for some reason I am not getting it.  An explanation would be greatly appreciated! Or if you have a different solution, that'd be cool too. Thanks!! I am running Ubuntu 14.04 on think-pad T450.  When using an external monitor with higher resolution than the in-built laptop screen, the text of dialog boxes are getting messed up.  Looks like I need to replace the Graphic card driver. Anyone found a solution to this?  Updated to add requested information:  lspci -nnk | grep '\[03' -A2   gives the following:  00:02.0 VGA compatible controller [0300]: Intel Corporation Broadwell-U Integrated Graphics [8086:1616] (rev 09)     Subsystem: Lenovo Device [17aa:5034] Kernel driver in use: i915   Below is a screenshot, see how the letters are messed up on the screen. This inequality $a+b^2+c^3+d^4\ge \frac{1}{a}+\frac{1}{b^2}+\frac{1}{c^3}+\frac{1}{d^4}$ let $0&lt;a\le b\le c\le d$, and such $abcd=1$,show that   $$a+b^2+c^3+d^4\ge \dfrac{1}{a}+\dfrac{1}{b^2}+\dfrac{1}{c^3}+\dfrac{1}{d^4}$$   it seems harder than Energy-momentum tensor transformation I've been trying to find how the energy-momentum tensor changes if we add a total derivative to the lagrangian: $$L\to L+\mathrm d_\mu X^\mu.\tag{1}$$   From the answer key:  $$T^{\mu\nu}\to T^{\mu\nu}+\partial_\lambda F^{\lambda\mu\nu}\tag{2}$$ Where $$F^{\lambda\mu\nu}=\frac{\partial X^\lambda}{\partial(\partial_\mu\phi)}\partial^\nu\phi -\frac{\partial X^\mu}{\partial(\partial_\lambda\phi)}\partial^\nu\phi.\tag{3}$$ Is the above answer right? I'm not able to get this result! any help? If $|f(z)|\le |g(z)|$, can we say $f$ is constant? Let $f$ and $g$ be entire functions and $g(z)\neq 0$ for all $z\in \mathbb{C}$. If $|f(z)|\le |g(z)|$, can we say $f$ is constant?  Liouville theorem says that an entire bounded function is constant, but g is not given bounded here. So I think it should be false. What else can we say about $f$? "Startup Applications" not working I have a simple one line command which works perfectly in terminal, but does not work in the "Startup Applications" app thing.  The line of code is : xmodmap /home/seph/Code/Ubuntu\ Scripts/Xmodmap  It's not that much of a hassle to copy it from "Startup Applications" and paste it into terminal, but I don't really get why it isn't working.  I followed someone else's instructions to do it in the first place, so maybe I did something wrong?  In any case, wouldn't it be the obvious and logical assumption that it just types whatever you put in it into Terminal? In transformers, the ratio of the voltages equals the ratio of the turns - so double the output coil's turns and the output voltage doubles. Then, in order to conserve energy, current halves.  This makes perfect sense in terms of $\mathrm{P=VI}$, but what happened to $\mathrm{V=IR}$? Doubling voltage and halving the current seems to completely contradict this basic law. That is, of course, unless the resistance in the output circuit changes, with R proportional to $\mathrm{V^2}$ - but I don't see how this is possible.  So how can a transformer obey both laws? Can resistance change or am I missing something else? For random variables $X \in \mathbb{R}^h$, and a positive semi-definite matrix $A$: Is there a simplified expression for the expected value, $\mathop {\mathbb E}[Tr(X^TAX)]$ and variance, $Var[Tr(X^TAX)]$? Please note that $A$ is not a random variable. Is there a way to have a 64 bit enum in C++?  Whilst refactoring some code I came across bunch of #defines which would be better as an enum, but being greater than 32 bit causes the compiler to error.  For some reason I thought the following might work:  enum MY_ENUM : unsigned __int64   {       LARGE_VALUE = 0x1000000000000000,   }; Changing underline color of LanguageTool in TeXstudio I've recently installed LanguageTool to check grammar and spelling mistakes in TeXstudio. However, I often miss the errors because the gray-bluish underlining makes them hard to spot. Is there a way to change the underlining to a distinctive color, such as red for example?   I checked . It says I have to do some changes to the .languagetool.cfg file, but for some reason this file doesn't appear in File Explorer. How to import all files of a folder at once? Uncertainty in parenthesis How do I expire a PHP session after 30 minutes? I need to keep a session alive for 30 minutes and then destroy it. Setting controller variables not reliable from apex:commandButton I'm trying to set a variable inside my controller via an actionFunction, which is called by some Javascript, which is initially called by either by an actionPanel (with styleClass='btn') or a commandButton.  If the caller is the actionPanel then the variable updates reliably. However with the commandButton I can see the updated value flash briefly before reverting to its previous value. Maybe one out of every six clicks of the button actually causes the new value to stick. Sometimes it can take a dozen or more tries, regardless of click frequency.  Can someone please explain what's going on here?  PAGE  &lt;apex:page controller="MyController"&gt;     &lt;apex:form &gt;         &lt;apex:outputPanel id="panel"&gt;             &lt;apex:outputText value="MyString = {!MyString}"/&gt;             &lt;apex:actionFunction name="SetString" rerender="panel"&gt;                 &lt;apex:param name="param1" value="" assignTo="{!MyString}"/&gt;             &lt;/apex:actionFunction&gt;             &lt;script&gt;                 function JSetString() {                     SetString('{!MyString}' + '.');                 }             &lt;/script&gt;             &lt;apex:outputPanel onclick="JSetString()" styleClass="btn"&gt;                 Grow {!MyString} (works)             &lt;/apex:outputPanel&gt;             &lt;apex:commandButton onclick="JSetString()" value="Grow {!MyString} (unreliable)" rerender="panel"/&gt;         &lt;/apex:outputPanel&gt;     &lt;/apex:form&gt; &lt;/apex:page&gt;   CONTROLLER  global class MyController {      public MyController() { MyString = 'hello'; }      public String MyString {get;set;} } Does Java have buffer overflows? Combining multirow and multicolumn When combining multirow and multicolumn in the same cell of a table I am getting extra vertical lines:  \documentclass[plain]{article} \usepackage{multirow} \pagestyle{empty}  \begin{document}  \begin{tabular}{|l|l|l|l|}\hline   \multirow{10}{*}{numeric literals} &amp; \multirow{5}{*}{integers} &amp; in decimal &amp; \verb|8743| \\ \cline{3-4}   &amp; &amp; \multirow{2}{*}{in octal} &amp; \verb|0o7464| \\ \cline{4-4}   &amp; &amp; &amp; \verb|0O103| \\ \cline{3-4}   &amp; &amp; \multirow{2}{*}{in hexadecimal} &amp; \verb|0x5A0FF| \\ \cline{4-4}   &amp; &amp; &amp; \verb|0xE0F2| \\ \cline{2-4}   &amp; \multirow{5}{*}{fractionals} &amp; \multirow{5}{*}{in decimal} &amp; \verb|140.58| \\ \cline{4-4}   &amp; &amp; &amp; \verb|8.04e7| \\ \cline{4-4}   &amp; &amp; &amp; \verb|0.347E+12| \\ \cline{4-4}   &amp; &amp; &amp; \verb|5.47E-12| \\ \cline{4-4}   &amp; &amp; &amp; \verb|47e22| \\ \cline{1-4}   \multicolumn{3}{|l|}{\multirow{3}{*}{char literals}} &amp; \verb|'H'| \\ \cline{4-4}   &amp; &amp; &amp; \verb|'\n'| \\ \cline{4-4}   &amp; &amp; &amp; \verb|'\x65'| \\ \cline{1-4}   \multicolumn{3}{|l|}{\multirow{2}{*}{string literals}} &amp; \verb|"bom dia"| \\ \cline{4-4}   &amp; &amp; &amp; \verb|"ouro preto\nmg"| \\ \cline{1-4} \end{tabular}  \end{document}     Notice the vertical lines in the char literals and string literals cells (which should span three columns). How can they be avoided? Construct ideals in $\mathbb Z[x]$ with a given least number of generators Obviously, most beers are carbonated with carbon dioxide, while some stouts/porters are "carbonated" with nitrogen.  I was curious if there has been any notable experimentation with other gasses to "carbonate" beer. If nitrogen can introduce a "creamy" texture to a beer, I would think that other gasses would also be able to introduce their own characteristics on beer. If any of these experiments have done, what characteristics do these other gases impart?  I'm sure cost would be an issue for certain gasses that would prohibit its use in beer, but for purposes of this question, cost is irrelevant.  As an aside, what is the correct term to use, as opposed to "carbonate", for a question of this nature? How can I give a user one password for normal usage when logging in, and another password for system administration and sudo access? I want one user to have two passwords.