Critical Policy Violation email from Google Cloud Platform. What to do?
How do I deal with a compromised server?
Creating 3D model in QGIS? Can I create a 3D model in QGIS or is there some model for 3D city models? Evaluation of Differentiation and Integration I was having some thought about what would be the syntax to make the end point evaluation of derivatives or integrals. Such as making the | with the two end points of evaluation on the top an bottom of the line. Any suggestions would be wonderful. Is Using Digital Signatures to prove identity a zero knowledge proof? Suppose Alice publishes a book with a public key in it, and later wants to prove that she wrote the book. She could sign challenge messages with her private key, and others could verify those signed messages. Alice is proving she knows a private key without revealing anything about it.  Is this an example of an interactive zero knowledge proof?   Or does this example somehow not apply to zero knowledge proofs? Why doesn't the "zig-zag" comb deformation retract onto a point, even though it's contractible? I am starting to read Hatcher's book on Algebraic Topology, and I am a little stuck with exercise 6(c) in Chapter $0$. Unfortunately a picture is involved so it doesn't quite make sense for me to repeat it here - but I'll do it anyways (maybe it helps)     Let $Z$ be the zigzag subspace of $Y$ homeomorphic to $\mathbb{R}$ indicated by the heavier line in the picture:       Show there is a deformation retraction in the weak sense of $Y$ onto $Z$, but no true deformation retraction."   Now the definition for deformation retraction and weak deformation retraction as as follows:  We say that $f: X \to X$ is a deformation retraction of a space $X$ onto a subspace $A \subset X$ if there exists a family of maps $f_t : X \to X$ with $t \in [0,1]$ such that $f_0 = \mathbb{1}$ (the identity) and $f_1 (X) = A$ and also $f_t$ restricts to the identity on $A$ for each $t$.   A weak deformation retraction is almost the same, only that we now relax the conditions $f_1(X) = A$ to $f_1 \subset A$ and, for each $t \in [0,1]$ we require that $f_t(A) \subset A$.  Hence, as far as I understand the question and the concepts involved, I need to show that basically no map can be constructed such that the bold zigzag - line stays put while the thin lines retract to the bold line over a finite time interval $0 \leq t \leq 1$. However, I should be able to show that I can pull the thin lines continously onto the thick line, provided I am allowed to move points on the zigzag line .. is that correct ?  Now, the problem is I can't see why I shouldn't be able to do the former, given that I could find a weak deformation retract. Any help would be great! Discoveryd Alternative to Replace mDNSResponder Argument? This is a direct follow-on to . , I'd add the "-AlwaysAppendSearchDomains" argument to the mDNSResponder plist file so that all local resolver lookups added the search domains, regardless of whether there was a period in the label to be looked up. For example, whether I try to ssh to hostname foo.bar or foo, the search domain of baz.com should be tried, not only for the latter case, as was (and is) the default behavior.   Now, it looks like the mDNSResponder is gone, replaced with discoveryd. I cannot find a similar option to get it to always appending the search domain. Suggestions? I'd rather not go the route of using a non-default local resolver, but I'd consider it as an option. For now, I'll just type in the long FQDNs, but I'd really rather not.  Thanks, Pete The sine inequality $\frac2\pi x \le \sin x \le x$ for $0<x<\frac\pi2$ How to prepare data for ListVectorPlot[]? Is there something wrong with VertexConnectivity Functional equations leading to sine and cosine How to collapse unused parameters in moderncv? I am writing my CV using the moderncv package. I already have adjusted the CV to meet my needs. Therefore I amplified the maximum number of parameters possible in the \cventry command. However, now I have some ugly spacing in case I do NOT use all parameters (see second \cventry in the MWE for illustration):  Any suggestions to make the spacing collapse in case not all parameters are occupied? As you can see from the MWE I already have adjusted for \ifthenelse command. I use texlive 2014.  \documentclass[11pt,a4paper,sans]{moderncv} \moderncvstyle{banking} \moderncvcolor{blue} \usepackage[scale=0.7]{geometry} \name{John}{Doe} \title{Resume title} \address{street and number}{postcode city}{country} \phone[mobile]{+1~(234)~567~890}  \renewcommand*{\cventry}[9][.4em]{%  \begin{tabular*}{\textwidth}{l@{\extracolsep{\fill}}r}%  \ifthenelse{\equal{\bfseries #4}{}}{}{{\bfseries #4}} &amp; \ifthenelse{\equal{\bfseries #5}{}}{}{{\bfseries #5}} \\%   \ifthenelse{\equal{\itshape #3}{}}{}{{\itshape #3\ifthenelse{\equal{#6}{}}{}{, #6}}} &amp; \ifthenelse{\equal{\itshape #2}{}}{}{{\itshape #2}}\\%  \ifthenelse{\equal{#7}{}}{}{{#7}} &amp; \ifthenelse{\equal{#8}{}}{}{\\ {#8} &amp; \\}% \end{tabular*}%  }  \begin{document} \makecvtitle \section{Education} \cventry{Grade}{Degree}{Institution}{year--year}{M.Sc.}{Majors}{Majors}{} \cventry{}{Degree}{Institution}{City}{}{}{}{} \cventry{year--year}{Degree}{Institution}{City}{Grade}{Majors}{Majors}{} \end{document} Am wondering if somewhere there is a list of industry "minimums" for browser support. My company release two "portals" over the past 6 months and did very little to support IE8 users, who at this time, according to my G Analytics makes up about 14% of all IE visitors. Amazingly enough IE7 is 25%...  Figured support for IE7 was out the window already, but figured 14% was significant enough to warrant some support.  Any arguments to support my side of wanting to support IE8?  Any arguments to NOT support IE8? Summing Up A 2D Array iPhone's Bluetooth - What? Why? How? I googled a lot and read many documents. But I can't understand the concept behind iPhone's Bluetooth technology.  In my knowledge, Bluetooth was used for:   Transferring files between devices Wireless communication for things like video gaming and earphones   Recently I tried to copy some of the photos from my old Android mobile to my iPhone 4S via Bluetooth. It's quite simple in my older phones to connect with other devices by Bluetooth for file sharing. But I can't pair other devices (even another iPhone :( ) with my iPhone 4S.   Copying songs/videos may affect their iTunes as well as their business. But what about images? Why is the usage of Bluetooth restricted and what's the use of it being able to transfer images? Is there any other way to use iPhone's Bluetooth to transfer files? Maybe using an app? But I don't want to jailbreak my device.   I'm confused about the restrictions and Apple's thinking. How should I interpret this residual plot? I am unable to interpret this graph. My dependent variable is total number of movie tickets that will be sold for a show. The independent variables are the number of days left before the show, seasonality dummy variables (day of week, month of year, holiday), price, tickets sold till date, movie rating, movie type (thriller, comedy, etc., as dummies). Also, please note that movie hall's capacity is fixed. That is, it can host maximum of x number of people only. I am creating a linear regression solution and it's not fitting my test data. So I thought of starting with regression diagnostics. The data are from a single movie hall for which I want to predict demand.  The is a multivariate dataset. For every date, there are 90 duplicate rows, representing days before the show. So, for 1 Jan 2016 there are 90 records. There is a 'lead_time' variable which gives me number of days before the show. So for 1 Jan 2016, if lead_time has value 5, it means it will have tickets sold until 5 days before the show date. In the dependent variable, total tickets sold, I will have the same value 90 times.  Also, as a side remark, is there any book that explains how to interpret residual plot and improve model afterwards? Confusion on Derived Sets and the $n$-the Derived Set I want to solve the following exercise 1.3.C. from page 27 of R. Engelking: General Topology.  For every positive integer $n$ the $n$-th derived set $A^{(n)}$ of a subset $A$ of a topological space $X$ is defined inductively by the formulas: $$  A^{(1)} = A^d \quad \textrm{and} \quad A^{(n)} = (A^{(n-1)})^d. $$ (a) Give an example of a set of real numbers that has three consecutive derived sets distinct from each other.  (b) Give an example of a set of real numbers that has infinitely many derived sets distinct from each other.   The definition is $$   A^d := \{ x \in X \mid x \in \overline{A \setminus \{ x \}} \}. $$ I am confused, cause the set $A^d$ ist closed, i.e. $\overline{A^d} = A^d$. And closed means it already contains all its limit points, so how can than $(A^d)^d$ be different from $A^d$? inequality with three variables and condition How to randomly subset X% of selected points? What methods are available in ArcGIS 10.2 to randomly subset a selection of points.  For example, in the attached screenshot I am interested in keeping 20% of the selected points and deleting the rest. Let $F,G,H$ be groups such that $F\trianglelefteq G \trianglelefteq H$.  I am asked whether we necessarily have $F\trianglelefteq H$. I think the answer is no but I cannot find any counterexample with usual groups. Is there a simple case where this property is not true? Are threads implemented as processes on Linux? I'm going through , Advanced Linux Programming by Mark Mitchell, Jeffrey Oldham, and Alex Samuel. It's from 2001, so a bit old. But I find it quite good anyhow.  However, I got to a point when it diverges from what my Linux produces in the shell output. On page 92 (116 in the viewer), the chapter 4.5 GNU/Linux Thread Implementation begins with the paragraph containing this statement:     The implementation of POSIX threads on GNU/Linux differs from the   thread implementation on many other UNIX-like systems in an important   way: on GNU/Linux, threads are implemented as processes.   This seems like a key point and is later illustrated with a C code. The output in the book is:  main thread pid is 14608 child thread pid is 14610   And in my Ubuntu 16.04 it is:  main thread pid is 3615 child thread pid is 3615   ps output supports this.  I guess something must have changed between 2001 and now.  The next subchapter on the next page, 4.5.1 Signal Handling, builds up on the previous statement:     The behavior of the interaction between signals and threads varies   from one UNIX-like system to another. In GNU/Linux, the behavior is   dictated by the fact that threads are implemented as processes.   And it looks like this will be even more important later on in the book. Could someone explain what's going on here?  I've seen this one , but it doesn't help much. I'm confused.  This is the C code:  #include &lt;pthread.h&gt; #include &lt;stdio.h&gt; #include &lt;unistd.h&gt;  void* thread_function (void* arg) {     fprintf (stderr, "child thread pid is %d\n", (int) getpid ());     /* Spin forever. */     while (1);     return NULL; }  int main () {     pthread_t thread;     fprintf (stderr, "main thread pid is %d\n", (int) getpid ());     pthread_create (&amp;thread, NULL, &amp;thread_function, NULL);     /* Spin forever. */     while (1);     return 0; } Fix SD card that cannot be formatted