Dual Boot Ubuntu with Windows
How can I repair grub? (How to get Ubuntu back after installing Windows?)
How can a photon have no mass and still travel at the speed of light? Cleaning Circuits with Compressed Air I've been arguing with a colleague whether it is a sensible solution to clean dusty PCBs with compressed air. While I think this is the best solution (nothing touches the PCB), he claimed that spraying off the dust can cause ESD, because the charges that may have accumulated in the dust win't bleed off in the process (and it's better to leave everything as it is). I'm not really convinced by this argument and my (limited) knowledge of ESD production doesn't help getting peace of mind in this matter. What is your input? How to set up RAID 1? Access images inside jar Atmospheric pressure experiment using a cup with a fluid to hold a glass plate When I was in high school, my teacher did an experiment to show the power of atmospheric pressure.  Experiment: Prepare a glass bottle, fill with water, put a glass plate on the bottle, make sure there is no air in the bottle, just water. Hold the glass bottle and plate, and invert them. Slowly, release the hand which hold the plate. Because the atmospheric pressure, the glass plate will not fall down.    Question 1: As we know, if we didn't put water into the glass bottle, just air in the glass bottle the glass plate will fall down. So, If we use other liquid instead of water, this liquid has smaller density than water, like alcohol, the plate will not fall down. But, if we continue to chose the smaller density liquid until the liquid has density like air the plate will fall down. So, if there is a threshold density of liquid make the plate between falling  down and not falling down?  Question 2: If we put the bottle and plate into water slowly, when the plate and part of bottle are in the water but part of the bottle still above the water, will the plate fall down?  Question 3: Continuing question 2, when both bottle and plate are in the water I know the plate will fall down. So, how does the pressure of water and atmosphere change?  Is there a good description of this phenomena?  Why does the trick continue to work with lower density fluids and why does placing the plate in the water cause it to fall? Gummy residue from baking spray/oil I'm sure everyone's seen this - that brownish stuff left behind when you grease an area of a baking dish that gets left exposed to the heat. Soap doesn't bother it too much, and it likes to gum up my scrubber. What's going on there, and are there any easy ways to get it off? Should I use a categorical cross-entropy or binary cross-entropy loss for binary predictions? First of all, I realized if I need to perform binary predictions, I have to create at least two classes through performing a one-hot-encoding. Is this correct? However, is binary cross-entropy only for predictions with only one class? If I were to use a categorical cross-entropy loss, which is typically found in most libraries (like TensorFlow), would there be a significant difference?  In fact, what are the exact differences between a categorical and binary cross-entropy? I have never seen an implementation of binary cross-entropy in TensorFlow, so I thought perhaps the categorical one works just as fine. Installing Ubuntu with Fake RAID 1 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,   }; CSS transition shorthand with multiple properties? Sometimes after I fry something, I wash it immediately in water because it's a bit easier to wash (before the remains stick to the pan).  Does this damage the pan in any way? How do I cash a USD cheque in Europe, quickly? I'll receive a USD cheque shortly. I prefered payment by money transfer, but all attempts to do so - i.e. SWIFT/IBAN, Payoneer, transferwise - failed. Now I will receive a cheque by mail.  I contacted my bank and they say that they can cash a cheque for me, given a (prob hefty) fee. The bank employee was so kind to warn me, that in case of a cheque the funds are cashed, but reserved until the legal reimbursement period ends, which apparently is between 3 and 6 months.   Is there really no quicker way to receive payments by cheque and have access to the funds quickly? How can I do development on my Android device? I have a pretty long commute to work and own an android phone. I figure it would be nice to do some simple programming on the way. I'm not picky on which language to code on. I usually have an internet connection on the train.  I've been looking through the android market but haven't found any apps that offer a "development environment" or an editor with a compiler. Is any development ON the Android possible? Does an app for this exist? C# 4.0 optional out/ref arguments What is a decoupling capacitor and how do I know if I need one? What is a decoupling capacitor (or smoothing capacitor as referred to in the link below)?  How do I know if I need one and if so, what size and where it needs to go?    mentions many chips needing one between VCC and GND; how do I know if a specific chip is one?   Would an  4-bit parallel access shift register used with an Arduino need one? (To use my current project as an example) Why or why not?  I feel like I'm starting to understand the basics of resistors and some places they're used, what values should be used in said places, etc, and I'd like to understand capacitors at the basic level as well. When is a CDATA section necessary within a script tag? Are CDATA tags ever necessary in script tags and if so when?  In other words, when and where is this:  &lt;script type="text/javascript"&gt; //&lt;![CDATA[ ...code... //]]&gt; &lt;/script&gt;   preferable to this:  &lt;script type="text/javascript"&gt; ...code... &lt;/script&gt; I am looking for a reference which has a self-contained (elementary, that is, at the "undergraduate algebra level") proof of the the fact that any one-dimensional Noetherian UFD is a PID. Does anyone know such a reference?   (Note: I have looked at the similar questions on this website but don't find them particularly useful). How long does it take for badges to be awarded? How are they generated? Do badges get calculated in real time, or do they get calculated by an external service? How long does it take for a badge to be awarded, once its requirements are met?  Does Stack Overflow use any external services to do things, like maintenance, e-mailing or badge calculation? How do I run wireshark, with root-privileges? A standard installation of Wireshark doesn't give the program permission to access the network interface.   I suppose I have to run the program with sudo, but do not know how to add it to the icon - if that's the way to do it. Set same icon for all my Forms Is there any way to set the same icon to all my forms without having to change one by one? Something like when you setup GlobalAssemblyInfo for all your projects inside your solution.