Do I need a transit visa as a Turkish citizen (with EEA permit) to transit from London Stansted?
Is there a way to find out if I need a transit visa for a layover in the UK?
I am asked to solve $$u_x+u_y=1$$ If is was homogeneous i.e., $u_x+u_y$ the answer would be $u(x,y)=f(y-x)$ where $f$ is an arbitrary function. I have found the following set of solutions: $$u(x,y)=\lambda x +(1-\lambda)y$$ where $\lambda$ is an arbitrary constant(real or imaginary). I just have no idea what method other then trial and error would have lead me here. Any ideas? Thanks! How can I list permissions of every component in a file path? Sometimes it is necessary to determine on which directory in a path access rights are limited. Here is an example:  $ ls /sys/kernel/debug/usb/devices ls: cannot access /sys/kernel/debug/usb/devices: Permission denied $ cat /sys/kernel/debug/usb/devices cat: /sys/kernel/debug/usb/devices: Permission denied   Neither ls nor cat shows where the user rights were limited.  What is the simplest way of showing the access rights for every component (directory and the file) in the path? I am mainly interested in solutions for Unix-like systems. Count work days between two dates How can I calculate the number of work days between two dates in SQL Server?   Monday to Friday and it must be T-SQL. The second part of an exercise asks that I show:     There does not exist a surjective bounded linear map from $\ell^2(\mathbf{N})$ to $\ell^1(\mathbf{N})$.     The first part was to show that these two spaces are separable in their respective $L^p$ norms.    I've really hit a wall on this one.  I know, in fact, that there does exist a surjective bounded linear map from $\ell^1(\mathbf{N})$ to $\ell^2(\mathbf{N})$.  So my intuition says that if there were also one going the other way, then the two spaces would have to be isomorphic, which is false .  But I don't know of any such theorem that I could apply to "the category of Banach spaces".    My only other idea is to argue by contradiction using the open mapping theorem, but nothing is coming to me...  My guess is that separability is also going to be important, given the first part of the exercise.  -Thanks. Which textbook is good for introductory group theory? I'm writing an essay, and want to know the promotion rate and average duration from assistant professor to associate professor and associate professor to professor in recent years. Sadly I don't know the data for the US. Could anyone tell me? If a ring element is right-invertible, but not left-invertible, then it has infinitely many right-inverses. Let $A$ be a ring and $a\in A$ an element that has a right-inverse but does not have a left-inverse. Show that $a$ has infinitely many right-inverses. I am Peruvian, and will study in the Turkish Republic of Northern Cyprus for two years.  As a South American, what problems may I have if I decide to study in the TRNC, as it is recognized only by Turkey?  What if, having been in the TRNC, I decide to travel to the EU (Amsterdam) for summer vacations? Would I encounter any problem entering The Netherlands, a member of EU, after having been in the TRNC?  I have read that many tourists (Russians and Asians for now) are deported mostly because they go from Northern Cyprus to the Republic of Cyprus. Cyprus, a member of the EU, believes that those entering the country from the north are illegal immigrants. Does this rule apply to Cypriot internal issues only, or does it extend throughout the EU? Will it cause problems for my intended travel to Amsterdam? Running tcpdump starts ssh flood I have runtime Linux running in a PLC. My development machine is running Ubuntu 14.04. The PLC and the development machine are connected through a five port switch. I ssh to PLC from my development machine to transfer executable of a networking application that I develop on my development machine.   I run tcpdump on PLC to debug the kind of packets my network application is receiving BUT as soon as I start tcpdump, there starts a flood of ssh sync and acks back and forth from my ubuntu machine to the PLC. The LED lights of ethernet controller of PLC as well on the switch start blinking rapidly. The flood overwhelms the PLC and it almost dies down while all other packets get dropped. It feels like a DOS attack whenever I run tcpdump but as soon as I stop tcpdump, everything calms down and gets back to the normal.   I would like know remedy on this problem and why it happens?     Any help would be appreciated. What cause the "from review" links to appear in comments? I sometimes see comments ending in "From Review" (hyperlinked to a review page) on questions and answers, e.g.        I spend a good bit of time in the review queues (on Unix &amp; Linux), but comments I make do not come with these "From Review" links. Note that I only have access to the "First post" and "Late answer" queues.  Do these links only appear for the higher-rep queues? Rep graph overview thing™ is white (only in latest Chrome) As you can see, if you go to the reputation graph on your profile on Stack Overflow, the bars in the bottom overview will be white. This makes them invisible unless they are selected.  Eeek!  This does not happen on meta or any other site. Also, I cannot seem to reproduce it on others' profile. Possibly a bug only on your own profile? EDIT: I think I've existed for too long. If I change the CSS on one of the bars to stroke: none, then it becomes green. I think the outline is covering the fill because the bars are too skinny. EDIT2: Confirmed hypothesis by reproducing on Jon Skeet's graph. Proposed solution: enforce minimum bar width and add horizontal scrollbar. EDIT3: Can only repro on Chrome 29.0.1547.57 (Official Build 217859) m (the latest version). Norepro on older versions of Chrome, IE9 (winces), all versions of FF, and all versions of Safari. EDIT4: Can be fixed simply by running the JavaScript $('rect').css('stroke-width', '0') or a userstyle rect { stroke: none }. I may make a user[style|script] to fix this. I've noticed this on occasion with a variety of applications. I've often thought it was because the output was cancelled early (ctrl+c, for example) or something similar, and zsh is filling in a new line character. But now curiosity has gotten the best of me, since it doesn't seem to do this in bash.   zsh    bash    The Sequence program is something I pulled from a book while reading on Java certifications and just wanted to see if it would compile and run. I did notice that it does not use the println() method from the System.out package/class. Instead it uses plain old print().  Is the lack of a new line character the reason I get this symbol? Review bans should escalate beyond 30 days Dirac delta function and volume charge density I just got introduced to the Dirac delta function and one of the questions was to express volume charge density $\rho({\bf r})$ of a point charge $q$ at origin. I saw that the answer is related to Dirac delta function as: $$\rho({\bf r}) = q \delta^3({\bf r})$$ where $\delta^3({\bf r})$ is the 3-dimensional Dirac Delta function. Why is it so? Using indefinite articles before adjectives: "Let's have a good breakfast" Let's have breakfast    Let's have a good breakfast      I've learned that indefinite articles aren't used before uncountable nouns, so why is a used before the adjective "good" here?    Is there an exception to the rules or is it wrong? Black body radiation and spectra lines My understanding was that all objects emit light of continuous spectrum when hot ( black body radiation) but then you see discreet wavelengths in spectra lines and I am confused. I know I am making a mistake somewhere but not able to point it Cutting strands of wire to fit plug I am a hvac tech, but my question is I have 2awg stranded and my plug is 6awg, will it matter much if I cut some strands to fit my plug? the plug is 60amp 250vac for a piece of kitchen equipment if the matters. Eclipse: Can you format code on save? In Eclipse, under Windows -> Preference -> Java -> Code Style, you can define code templates for comments and code, and you can setup a code formatter.   I'm wondering if it is possible in Eclipse to have these setting take affect every time I save a source file.  Basically, instead of me highlighting everything and pressing Ctrl+Shift+F, I want Eclipse to be responsible for making sure my code is formatted properly.  Is this possible and how do you set it up?  Note On Using the Auto-Format:  It's probably best to choose "Format Edited Lines" as merging changes becomes very difficult when you reformat a whole file that is in source control already that was not formatted properly. Already did this to a co-worker. How to Split Features in QGIS? Why use gradient descent with neural networks? When training a neural network using the back-propagation algorithm, the gradient descent method is used to determine the weight updates. My question is: Rather than using gradient descent method to slowly locate the minimum point with respect to a certain weight, why don't we just set the derivative $\frac{d(\text{Error})}{dw}=0$, and find the value of weight $w$ which minimizes the error? Also, why are we sure that the error function in back-propagation will be a minimum? Can't it turn out the error function is a maximum instead? Is there a specific property of the squashing functions that guarantees that a network with any number of hidden nodes with arbitrary weights and input vectors will always give an error function that has some minima?