It has 3 gears in the front and 7 gears in the rear. And the derailers are suntour XC-Master.
My chain broke and in a moment of silliness (I was cold wet and slightly annoyed)  I threw the broken one away before thinking about measuring the new one.  Is there a guide to getting the chain length/tension correct ?  It's an 8 speed road bike (Shimano Sora back, double ring front)
Thousands of .log files in Exchange 2007 Server folder I'm a bit of an Exchange admin noob so I don't know if this is normal, but on our Exchange 2007 server under C:\Program Files\Microsoft\Exchange Server\Mailbox\First Storage Group\ there are 30,000 1MB .log files.  I don't know if those should be there or not, but they keep multiplying like little jackrabbits.  I've so far resisted deleting them as I'm sure something would break, but it's come to the point now where our 80GB disk is completely full up and Exchange has stopped receiving messages.  My best guess is that these are transaction logs and would be useful in rebuilding the database should something go awry, but 30GB of transaction logging seems a bit excessive.  Is there a way to limit it or is that even a good idea?  And of course did I completely miss the point? Lagrangian of Schrodinger field The usual Schrodinger Lagrangian is $$ \tag 1 i(\psi^{*}\partial_{t}\psi ) + \frac{1}{2m} \psi^{*}(\nabla^2)\psi, $$ which gives the correct equations of motion, with conjugate momentum for $\psi^{*}$ vanishing. This Lagrangian density is not real but differs from a real Lagrangian density  $$ \tag 2 \frac{i}{2}(\psi^{*}\partial_{t}\psi -\psi \partial_{t}\psi^{*} ) + \frac{1}{2m} \psi^{*}(\nabla^2)\psi $$ by a total derivative.  My trouble is that these two lagrangian densities lead to different conjugate momenta and hence when setting equal time commutation relations, I am getting different results (a factor of 2 is causing the problem). I can rescale the fields but then my Hamiltonian also changes. Then applying Heisenberg equation of motion, I don't get the operator Schrodinger equation.   Is it possible to work with the real Lagrangian density and somehow get the correct commutation relations? I would have expected two Lagrangians differing by total derivative terms to give identical commutation relations (since canonical transformations preserve them). But perhaps I am making some very simple error. Unless all conjugate momenta are equivalent for two Lagrangians differing by total derivatives, how does one choose the correct one?   I guess the same thing happens for other first order systems like Dirac Lagrangian also. Let $\Omega$ be an open subset in $\mathbb{C}$. Let $\{f_n\}$ be a sequence of holomorphic functions on $\Omega$ such that $f_n\to f$ pointwise and converges uniformly on any compact subset $K\subseteq \Omega$. Then by Cauchy Theorem and Morera Theorem, $f$ is holomorphic. Let $f_n$ and $f'$ be the derivatives of $f_n$ and $f$ respectively. Prove that $f_n'\to f'$ uniformly on any compact subset $K\subseteq \Omega$.   How to prove? Salesforce Toolkit for .Net with silverlight 5 I am creating a application with Silverlight 5 in which I have to communicate with Salesforce APIs.  Currently I used Salesforce toolkit for .net (version 1.2.1) by I am gettting error after using authentication method as -     The base class or interface 'System.Object' in assembly   'System.Runtime, Version=4.0.0.0, Culture=neutral,   PublicKeyToken=b03f5f7f11d50a3a' referenced by type   'Salesforce.Common.AuthenticationClient' could not be resolved.   System.runtime dll is referenced my application.   And Latest version of toolkit is even not installing in application. There is some compatibility issue with silverlight 5.  As per github and blogs Salesforce Toolkit is compatible with Silverlight 5. I installed it using nuget package manager.  Any idea to fix this ?  Thanks, $\lim\limits_{n \to{+}\infty}{\sqrt[n]{n!}}$ is infinite XeLaTeX update [20201004] and item ball in Beamer Beamer item balls go missing while compiling in XeLateX since yesterday's TeXlive update, however, the same code works with pdfLaTeX. Any solution, please. Here is my MWE: \documentclass{beamer}  \setbeamertemplate{itemize item}[ball] \setbeamertemplate{enumerate item}[ball]  \begin{document}  \begin{frame} \frametitle{A tested title} text \begin{enumerate}     \item this is an item \end{enumerate} text3 \begin{itemize}     \item this is an item \end{itemize} \end{frame} \end{document} I'm writing a set of course notes that has an appendix containing many activities.   I do not wish the activities to be shown in the Table of Contents, but I do wish them to be numbered. Here is the solution I was using:  In the preamble:  \newcommand{\activity}[2]{\bgroup\let\addcontentsline=\nocontentsline#1{#2}\egroup}   and now my "activity" starts out with:  \newpage \activity\section{A Fun Educational Activity}   There is only one problem. The activity starts out indented, as opposed to not indented, as a section should be.   How do I make my activity start out without an indent?  I realize I could simply add \noindent but it seems to me that there should be a more elegant solution. Can I prevent/restrict standard users from installing/uninstalling software? Can i prevent/restrict standard user from installing/uninstalling software in Ubuntu 12.04 desktop? Once I reach 15 reputation, will my old votes be taken into account? Users below 15 reputation can't effectively vote. It says:     Votes cast by those with less than 15 reputation are recorded, but do not change the publicly displayed post score   Does it mean that they will take effect after I reach 15 reputation or because they were cast before, they're recorded but ignored? How do I change the email address used for Google Play? My email address I use for the Play Store will be invalid soon, so I need to change it. However I don't want to make a new account because I want to keep all my apps. How can I do that? What does it mean to "program to an interface"? I have seen this mentioned a few times and I am not clear on what it means. When and why would you do this?   I know what interfaces do, but the fact I am not clear on this makes me think I am missing out on using them correctly.   Is it just so if you were to do:  IInterface classRef = new ObjectWhatever()   You could use any class that implements IInterface? When would you need to do that? The only thing I can think of is if you have a method and you are unsure of what object will be passed except for it implementing IInterface. I cannot think how often you would need to do that.   Also, how could you write a method that takes in an object that implements an interface? Is that possible? Simulating group_concat MySQL function in Microsoft SQL Server 2005? I'm trying to migrate a MySQL-based app over to Microsoft SQL Server 2005 (not by choice, but that's life).  In the original app, we used almost entirely ANSI-SQL compliant statements, with one significant exception -- we used MySQL's group_concat function fairly frequently.  group_concat, by the way, does this: given a table of, say, employee names and projects...  SELECT empName, projID FROM project_members;   returns:  ANDY   |  A100 ANDY   |  B391 ANDY   |  X010 TOM    |  A100 TOM    |  A510   ... and here's what you get with group_concat:  SELECT      empName, group_concat(projID SEPARATOR ' / ')  FROM      project_members  GROUP BY      empName;   returns:  ANDY   |  A100 / B391 / X010 TOM    |  A100 / A510   So what I'd like to know is: Is it possible to write, say, a user-defined function in SQL Server which emulates the functionality of group_concat?   I have almost no experience using UDFs, stored procedures, or anything like that, just straight-up SQL, so please err on the side of too much explanation :) How do you compute negative numbers to fractional powers? How to install program to all user accounts in Windows? I have several accounts on my home PC. I want to install a program for all user accounts, not just the one I used to perform the installation. How do I go about doing this?  I installed a program from an admin account, but it doesn't show up in the other local accounts.  I was not able to find any documentation on how to do this.  I have Windows 8.1, if that matters. Why does the following code sometimes causes an Exception with the contents "CLIPBRD_E_CANT_OPEN":  Clipboard.SetText(str);   This usually occurs the first time the Clipboard is used in the application and not after that. There exists $C\neq0$ with $CA=BC$ iff $A$ and $B$ have a common eigenvalue Question:  Suppose $V$ and $W$ are finite dimensional vector spaces over $\mathbb{C}$. $A$ is a linear transformation on $V$,  $B$ is a linear transformation on $W$. Then there exists a non-zero linear map $C:V\to W$ s.t. $CA=BC$ iff $A$ and $B$ have a same eigenvalue.  ===========This is incorrect==========  Clearly, if $CA=BC$, suppose $Ax=\lambda x$, then $B(Cx)=CAx=C(\lambda x)=\lambda (Cx)$, so $A$ and $B$ have same eigenvalue $\lambda$. On the other hand, if $A$ and $B$ have a same eigenvalue $\lambda$, suppose $Ax=\lambda x, By=\lambda y$. Define $C:V\to W$ s.t. $Cx=y$, then $BCx=By=\lambda y=C\lambda x=CAx$. But I don't kow how to make $BC=CA$ for all $x\in V$.   ====================================== Is there a way of conditionally triggering a compile-time error in verilog? I have a parameterised module in verilog, where the parameters are a clock rate and refresh rate, which is used to calculate how many cycles of inactivity are inserted between instances of a repeating operation.  However, it is very easy to set parameters that cannot be attained (because the operation takes a non-trivial length of time, so the repeat would have to occur before it had completed), and at the moment the design does not give any feedback on this.  I was wondering if there was some way I could trigger an error during synthesis (or compilation prior to simulation) if the conditions cannot be met (i.e. if one localparam is less than another)?  Some equivalent of the popular C/C++ compile-time-assert hack, perhaps. Rules for "on", "at", and "in": preposition of time Is there a name for function with the exponential property $f(x+y)=f(x) \cdot f(y)$? I was wondering if there is a name for a function that satisfies the conditions  $f:\mathbb{R} \to \mathbb{R}$ and $f(x+y)=f(x) \cdot f(y)$?  Thanks and regards! What type of lens will auto-focus on Nikon bodies without a focus motor?