How to return the Windows Authenticated username instead of the App Pool user in IIS?
How to get the current user in ASP.NET MVC
How to protect website from bulk scraping /downloading? Find generator of multiplicative group of $\mathbb{F}_{27}$ I have a finite field $\mathbb{F}_{27}$. I need to find an element of order 13. I know that multiplicative group of this field is cyclic with order 26. So I want to find a generator $g$ of this cyclic group, then $g^2$ will have order 13. Also I know that all elements of this field can be represented by polynomials from $\mathbb{F}_3[t]$, where t is root of irreducible polynom $x^3-x-1$.  Probably we can find generator of $\mathbb{Z}_{26}$ and than build an isomorphism to $\mathbb{F}_{27}\setminus 0$.  Anyway I don't know were to start.  Thanks! How to use aes-encryption in PostgreSQL? I tried aes-encryption by using following statement:  SELECT encrypt('test', 'key', 'aes');   which worked, but I am not able to decrypt the value. I inserted it in a field of datatype bytea but I'm not sure if that was the right way.   SELECT decrypt(pw, 'key', 'aes') FROM table WHERE ID = 1;   gives me the error     ERROR:  function decrypt(bytea, unknown, unknown) does not exist   LINE 1: SELECT decrypt(pw, 'key', 'aes') FROM tabelle WHERE ID = 7;                  ^   HINT:  No function matches the given name and argument types. You might need to add explicit type casts.   Does that really mean that encrypt() is an existing function, but not decrypt()? How else could I retreive aes-encrypted values? How can I run the following xrandrcommand on startup?  xrandr   cvt 1368 768  xrandr --newmode "1368x768_60.00"   85.25  1368 1440 1576 1784  768 771 781 798 -hsync +vsync xrandr --addmode VGA1 1368x768_60.00 xrandr --output VGA1 --mode 1368x768_60.00 Does the word discharge sound more like /dɪstʃɑːʳdʒ/ or /dɪsdʒɑːʳdʒ/? How about exchange or disproportion? Do they sound more like /ɪkstʃeɪndʒ/ or /ɪksdʒeɪndʒ/? /dɪsprəpɔːʳʃən/ or /dɪsbrəpɔːʳʃən/? I know the word student which commonly sounds like /sdjuːdənt/. and the dictionary says its IPA transcription is /stjuːdənt/. youtube-dl failed to extract signature It is considered very useful to utilize youtube-dl software for downloading youtubes.  A message is seen and it stopped working, which is following.  ERROR: Signature extraction failed: Traceback (most recent call last):   File "/usr/lib/python2.7/dist-packages/youtube_dl/extractor/youtube.py", line 479, in _decrypt_signature     video_id, player_url, s   File "/usr/lib/python2.7/dist-packages/youtube_dl/extractor/youtube.py", line 383, in _extract_signature_function     res = self._parse_sig_js(code)   File "/usr/lib/python2.7/dist-packages/youtube_dl/extractor/youtube.py", line 454, in _parse_sig_js     u'Initial JS player signature function name')   File "/usr/lib/python2.7/dist-packages/youtube_dl/extractor/common.py", line 391, in _search_regex     raise RegexNotFoundError(u'Unable to extract %s' % _name) RegexNotFoundError: Unable to extract Initial JS player signature function name; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update. ; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.   What should I do to proceed? why are the best questions the ones which have been closed? I frequently come across a really useful answer on StackOverflow which has been closed because it doesn't match the Q&amp;A format.  Examples include  ,  ,   ,  and there are others.  Where should this information be exchanged if it's not on stackoverflow?  It seems the moderators are often somewhat overzealous...  ---edit  When I say best, I mean they are informative and useful for someone who's looking for an answer to them.  Even if they do become a bit of a discussion, I value other people's opinions on the relative merits of the different JPA frameworks.  I come here looking to choose one and the answer helps me.  So what if it's not a definitive answer?  ---edit  I don't care how popular a question is, nor how interesting it is.  Users are interested in stuff that's useful to them.  Plenty of those were useful (as judged by the upvotes on the answers: 'This answer is useful'), but closed because they didn't have a definitive answer, as far as I can tell.  ---edit  Seems I'm not the first person to think this: there are various similar questions to mine like this one:   In it the user lists lots of other useful questions which have been closed:                    So isn't there a place on stackoverflow for these questions?  A discussion section, maybe? Is it possible/sensible to add a suspension fork to an old mountain bike? I have a ~1993 Giant mountain bike.  It's not great, but I am a very new and casual rider.    The bike has a solid fork and it makes for the predictable rough trail ride.  The trails are generally fairly modest (I live in North Texas, a 100' change in altitude makes our ears pop here) and the surface is generally dirt (very few rocky areas).  So, I am thinking that it would be very nice to have a suspension bike.  And seeing that a modest fork can be purchased for a modest price, I am wondering if it makes sense to add a fork to this bike.   asked about going the other direction, and there were some cautionary words about changing steering geometry.  So, on balance, is this something that I would be best off to avoid?  I suspect that if I have to replace a bunch of steering parts, the cost will quickly approach that of a new low end bike. ToList()-- does it create a new list? Use mathematical induction to prove $ (2n)!\geq 2^n(n!)^2$ for $n \in \mathbb{N}$ Fastest way to try all passwords Suppose you have a computer with a password of length $k$ in an alphabet of $n$ letters.  You can write an arbitrarly long word and the computer will try all the subwords of $k$ consecutive letters. What is the smallest word that contains all combinations of $k$ letters as subword? (i.e. the fastest way to hack the computer :) )  The smallest word that contains $n^k$ subwords of size $k$ has length $k-1+n^k$ and based on some easy cases, we would like to prove that it is in fact possible to find a word of such length that contains all possible passwords. The problem can be translated into a problem in graph theory, by taking as vertices all words of length $k$.  We tried $k=2$, where you can prove the conjecture by induction. For $n=2$ and small $k$ it also works. How do I create a reflective white material? I'm pretty new to this and this is my first question here, any help would be greatly appreciated.  So basically what I want to achieve is a floor material as seen in this photo...    ...the reflections are very crisp but dim.  With a glossy shader I get the following results:    First picture: reflections are blurry  Second picture: roughness of the material looks right but reflection is bright red  Third picture: If tinted in any other color than white, it seems to produce the result I want. Reflection is sharp and gets tinted blue. What I need is the reflection to be tinted white.  Thanks for any help. How can i find the python triggered by the GUI? What is the entropy of the universe today? What's the entropy of the universe today? How does one go about calculating this? I've heard the statement that black holes account for the bulk of the entropy in the universe today, but don't know why this would be true or the relationship between black holes and entropy. I am working on a Drupal mulsite project (using single database) and using Google Analytics module for this.  I have follow the below steps for GA configuration:   Created a domain name example1.com and a sub-domain name example2.com. Create an account on GA and create property for both of this domain name in GA account. Both property give me two different Tracking ID (same as below screenshot).      Into the configuration setting of GA from drupal admin section I have added Web Property ID of example1.com and into domain setting added both the domain name example1.com and example2.com into the section of List of top-level domains (a same as attached screenshot).      Now this configuration is only working for emample1.com, not for example2.com. So can anyone please tell me how can I use Web Property ID of domain exmaple2.php to get the result? In a simple battery + resistor circuit, what form of energy is lost from the electrons upon exiting the resistor? I will give this question a little context. Firstly, as I understand it, as soon as I "close the switch" on a circuit, electric current pretty quickly establishes a steady state where, at any given cross section along a wire, the average kinetic energy of that slice is both constant and equal anywhere along the wire. (Please correct me if I am misunderstanding).   If the average kinetic energy is constant anywhere throughout the wire in the circuit (which confuses me, as I would think that the electrons should all accelerate after exiting the resistor since they are no longer being impeded as much), that means that the average velocity is constant. So, in the example of a simple circuit with a battery of v Volts and a resistor of o Ohms, my question is the following:  Because a 'voltage drop' is known to occur across the resistor, what type energy is being "traded" to generate the heat that radiates from the resistor? I would think that the reflexive answer is "electrical energy"...hence the VOLTAGE drop (the sacrificed energy is clearly not kinetic, as the velocity is constant everywhere). However, I find this confusing. Does this mean that if I had a positive test charge, it would be easier for me to bring it to the beginning of the resistor as compared to bringing it to the end of the resister?     Further, if the correct answer IS "electrical energy", why exactly DOES electrical energy get "dissipated" as the electrons pass through the resistor? I always here the comment Oh! It's because all the electrons are running into densely packed crap which impedes their flow but that to me sounds like a reason for their KINETIC energy to be reduced. However, clearly that's not the case. So, ultimately, I guess the real question is:  **What goes on in the resistor that is literally removing electrical energy **. I am sure that this is a quantum mechanics question, but my quantum mechanics knowledge is not terribly strong. If I could get an answer that is devoid of crazy wave function equations, I would greatly appreciate it. Thanks! Filling a conical tank I have been working on this problem for about 2 hours and I can't seem to get it, here is exactly what the question reads. "Water is poured into the top of a conical tank at the constant rate of 1 cubic inch per second and flows out of an opening at the3 bottom at a rate of .5 cubic inches per second. The tank has a height of 4 inches, and a radius of 2 inches at the top. How fast is the water level changing when the water is 2 inches high?" pure code formatting, to enhance a question, is impossible (without 2k rep) Is there a word for describing people who know many things but superficially? Is there an appropriate word for the antonym of "full-stack", as in programming? Someone who knows a lot of things just as a full-stack programmer, but without mastering them. Suppose A is a 3*3  symmetric matrix s.t.  $$\begin{pmatrix} x &amp; y &amp; 1 \\   \end{pmatrix} A  \begin{pmatrix} x  \\  y\\ 1\end{pmatrix}  = xy -1 $$  let p be the no. of positive eigen value of A and q = rank(A)-p, then p=? q=?  what matrix A should be I can't find??