What are the downsides to sleeping in a hammock on a multi-day hike?

Question: I've read that hammocks are a very light way to travel through the wilderness. You just need the hammock, a cover, and a light sleeping bag, but there must be disadvantages compared to taking a tent or a bivy sack. What are they?
Comment: I use a Clark jungle hammock . I've had problems finding the right sleeping bag. It can be difficult to get inside the bag.Keep that in mind
Comment: Mosquitos and other bugs might be a problem.
Comment: That is a good hammock. It is made for the tropics. Sleeping bag? Normally a long sleave shirt & long pants is all needed. socks. It never drops below 70f. Maybe 60 in the sky islands.
Answer:
I've been a hammock backpacker for about three and a half years now. I love it. There's not a better way to backpack in the summer in my opinion. But despite numerous advantages to hammocking, there are some downsides (tradeoffs):

The biggest potential downside, as others have mentioned, is heat loss from the underside of the hammock, something my friends and I like to call "CBS" (cold butt syndrome). Insulation from clothing and sleeping bags is compressed and that limits the temperatures in which you can hammock comfortably with a sleeping bag. Adding a sleeping pad under you works fairly well but is not ideal because it adds additional weight (that you are trying to eliminate by hammocking.) Underquilts are the ideal insulation for cool-weather hammocking, but they are usually homemade or relatively hard-to-find compared to sleeping bags. Also the "bridge effect" comes into play when there is even the slightest breeze. The air moving below and above the hammock can cool you drastically, even in the summer. (That said, hammocking is perfect in hot weather.) Obviously this limits hammocking to primarily warmer months unless you have a bomb-proof hammock setup for winter (some do). However when you get to that point you may as well have a tent because any weight savings by using a hammock setup are essentially nullified by the extra gear and insulation needed (there are exceptions).
You can potentially get very wet if you don't learn to properly set up a good tarp or rain fly system over your hammock. However this is only at first. Once you get wet you learn really quickly. I've weathered some really nasty storms in my hammock and stayed completely dry with several different types of systems. Some are better than others. There is an art to a good tarp setup and so many ways that I won't go into it here. A good tarp set up will also the alleviate the problem of water running down your lines onto the hammock.
There is a learning curve. To get good and comfortable with regular sleeping in a hammock, then you have to be willing to change some habits and learn new ones. And there's all kinds of new gear to research and learn about (not a downside for me, but for some). So you have to learn what type of setup works best for you, and there are many to choose from.
You lose a certain amount of privacy. When tent-camping you can just get inside alone and change clothes with no one looking. When one only has a hammock with a tarp over it and no walls, then one must get a bit more creative to conceal one's man-parts or woman-parts when changing. Obviously at night this doesn't matter very much...unless your friends tend to pack night vision goggles. This one really isn't a big deal once you figure out the tricks, or you may not care.
Sharing a hammock overnight isn't really an option for most people, especially for a multi-day trip. If you try, it had better be someone you are willing to be up close and personal with all night long. Even the double-sized hammocks squeeze two people together, which just isn't comfortable for an extended period of time. It's also impossible to not disturb the other person in the hammock if you move at all or get out of it. Sharing a tent or a tarp-tent isn't nearly as hard to do.
Weight savings can actually be negated with multiple people. Consider this example: three people sharing the load of a modern lightweight or ultra-light 3-person tent (footprint, body, rainfly, poles, stakes) vs. 3 people carrying their own individual hammock set-ups (hammock, straps/rope/webbing, carabiners, tarp, stakes, no-see-um netting for some people too). Now this depends highly on the tent model and the type of hammock setup, but generally speaking you will likely save weight by splitting up the tent among all three people, especially if you are already using a sleeping pad in your hammock. A shared tarp-tent could mean even more weight savings. (There are ways around this dilemma. You can sometimes share a large tarp with several hammocks if the trees are arranged nicely.)
You aren't guaranteed to find good trees for your hammock at every campsite. This has certainly been a challenge at some places I've camped. If you doubt that the area you're visiting will be good for a hammock, then don't depend on the hammock as your primary shelter. Even if it's rocky, frozen, snow-covered, just sand, or other difficult terrain, you always have ground to set up a tent.
It's just plain harder to go to the bathroom at night! You get better at it with practice, but sometimes it is simply a pain to climb out of your sleeping bag and hammock, go relieve yourself while half asleep, and then try to wiggle back in to your hanging bed in which you were so, so comfortable. Plan ahead. Don't drink too many fluids before you go to sleep in a hammock.
Comment: Some hammocks, with a watertight bottom, can also be used as a small tent. Though not ideal, this significantly reduces the risk of not finding a suitable spot.
Answer: Hammocks are cold. The weight of your body compresses the clothes or sleeping bag, and air circulates underneath you, as opposed to a tent where you usually have a pad and the ground for insulation.
It seems like it would be tough to stay dry in the rain in a hammock. It's nice to have a tent to get into in the rain in between hiking/playing and sleeping if it's raining.
Comment: That's why you would use something like the hennessy hammock. They come with tarps for hanging above you for bad weather. http://hennessyhammock.com/catalog/#hammock They even have cold weather tests. http://hennessyhammock.com/articles/cold_weather_camping/
Comment: I slept on an [ENO ProNest Hammock](http://eaglesnestoutfittersinc.com/pronest.html) every night for approximately 3 months and can confirm what @xpda said - they're much colder than sleeping on a pad.

I also found it to be very uncomfortable after the first couple of weeks.
Comment: This answer is seriously outdated. You have an underquilt attached, which is exactly what it sounds like - a quilt that hangs just under the hammock, insulating the (and your) bottom. A tarp on top can be brought close in, so it is more like hanging inside a tent. Then you've solved insulation and blocked weather, all you need is a top quilt and you're ready for a good night's sleep! You also don't need expensive, brand-name gear; all these things are readily available if you just shop around a little. It's easy, modular, and fun. Source: am hammocker.
Comment: Nice!  I haven't seen that before.
Comment: Trust me you wouldn't want to sleep in a hammock in some of the UK wild areas..
Comment: UK is infamous for it wet and dump weather. One must be crazy to use hammock on those islands.
Answer: In a lot of places it will be quite difficult finding two trees the right distance apart to hang it. When it's late and you've been walking all day, all you want to do is lie down and rest, you might spend quite a long time looking for those two trees.
Here in the UK when it rains, it often comes horizontal, so even with a tarp over you, you're going to get wet. And maybe motion sickness if it's windy!
Answer: I am relatively new to hammock camping, but the only downside that I am aware of is possibly not being able to find a place to hang.  As others have mentioned, you do have to account for heat loss out of the bottom of the hammock, but that can be solved simply/cheaply by putting closed-cell foam pad in the bottom of the hammock (generally more expensive is the underquilt).  Be sure to check out http://hammockforums.net .  There is a great community of hangers there, from backyard and bedroom hangers to ultra-lightweight backpackers.
Answer: My experience with hammocks: serveral multi-day bike trips.
Downsides:
You need trees. Depending on the area this can be a problem. I have found myself looking desperately for trees in Hungary. On the other hand you may find spots to tie your hammock in strange places (abbandoned customs station, bridge)
The rain can be an issue, but that what your tarp is for. Also note that water comes down the lines of the hammock. Use a carabiner at the connection between the lines and the hammock.
Stormy weather can also be an issue. The problem can again be migrated with a change of location or a tarp.
Your sleeping bag will be compressed and you can get a cold butt. My solution: My hammock is double-walled and i put an insulated camping blanked between the lower walls.
Moskitos. Use a hammock with a mosquito net. Trust me.
Getting up at night can be uncomfortable (tall grass, slopes, dense bush)
Now the good parts: Space an weight of hammock and tarp are the same as a smaller sleeping bag. Setup within minutes, minimal footprint, sleeping on any slope trees grow, camping out of sight 10 meters next to a road. No worries about stones and roots below you.
Answer: Hammocks are great for hot weather.  I have backpacked with a hammock in the Virginia summer, when the nights were 85°F-95°.  There are certainly enough trees here, and in any densely forested area.  It is actually preferable (with a mosquito net) because you stay cooler.  When it rained, I slept on the ground with a small rain fly, because water likes to come down from the attachment points.  Bivys pack so small that if one were concerned about the weather, you could pack both in less space than a full sized tent.
Comment: It does give one downside- the water runoff...
Comment: Note on attachment points.  Just tie on a drip cord.  Usually I just attach a cord with a girth hitch.  This will redirect the water down at that point (follows gravity) instead of continuing into your hammock.
Comment: This doesn't answer the question of the downsides to using a hammock at all and would be more appropriate as a comment on the original post.
Comment: @RoryAlsop - Ok true it does give one. It was pretty late when I read this. It still seems to me more like a comment than an answer overall. I'm still relatively new here so I could be wrong.
Answer: I had the same worries as the OP, but a buddy of mine brought a store-bought hammock on a 3 night trip a few years ago.  I started investigating and found this site.  I made my own for a few bucks (< $20 for the ripstop nylon, a few bucks for some rings, a few more for straps, paracord and a couple carabiners), have used it for 2 years now, and it's still going strong.
The guy talks about staying dry (use a tarp), staying warm (he's got pictures of sleeping in several inches of snow), and keeping the bugs off, too.  I've never been cold in mine, but as Chad mentions (+1) it's easy to add an underquilt, if you like, and that's what I'd do if I were going to be somewhere below 40F.  I think Simon (+1) has a good point about finding the two trees, but you only need one (1) tree, and a sturdy stick of the appropriate height. (?!)  You attach one end to the tree, then run the other cord over the  stick/post then into the ground, and the hammock stabilizes itself (saw this somewhere that I can't quite find right now.  Try it!).
In short, after 20+ years of packing a tent around (and I tried a bivy once, but it was too cramped for me), I don't see myself taking anything other than a hammock for the forseeable future.  Your mileage may vary.
By the way, I've use the nylon hammock, an ordinary sleeping bag, and one of those egg-crate sleeping pads.  Just got a Therma-rest pad (the most expensive link in the chain) that I haven't tried yet.
Comment: Another BTW - I haven't done any long-term camping so cannot speak to long-term comfort of a hammock.  I've read accounts of some extended campers having trouble, and I recall one fellow who said it wasn't so bad.  I hope to one day have the opportunity to find out for myself.
Answer: One downside I've recently found out is that some hammock use can violate Leave No Trace policies.  If you aren't careful about the rig you use to hang the hammock, you could injure the trees.  The wider the strapping around the tree, the better for the tree.  I suppose this doesn't mean all hammocking is bad for LNT, but it is common to hang a hammock with ripcord or similar such rope, and that's supposed to be no good for most trees.
Some of the boy scout camps we go to mention this, although so far none prohibit use.  It's also part of our leadership training.  As a result, the scouts are recognizing some downsides but which can be mitigated with better equipment and training.  It is interesting to note that the BSA is also promoting the concept, and some troops are reporting complete conversion to hammock-only camping.
Consider:

Hammock Camping - LNT.org
LNT Skills - Hammock Camping

And some interesting dialog in this forum discussing a specific ban on the subject, as well as discusses some other downsides which, like my own answer, can be mitigated with proper resources and training:

Could use help here: Persuade a camp director that hammocks are OK
Answer: I believe you could be faced with back problems if you slept in a hammock every day of your life. I don't think it would be a problem for just a few days once in a while though.
Another problem probably worth mentioning is that, unlike a tent, you can't use your hammock (even with a tarp) to keep your gear out of the weather. Unless you bring your whole pack in the hammock with you, in which case you probably won't be very comfortable...
Comment: Most folks think of lying in a hammock in line with the two trees (or whatever main anchors you use), sometimes called a "banana".  If you instead lie diagonally (~45 degrees), the hammock material flattens out, and you can get pretty flat.  I have seen folks comfortably lie on their stomach with some configurations.
Comment: Actually it is very possible to keep your gear out of the weather in all but the worst of storms. I ,like many hammockers, use a ridgeline above my hammock from which to hang items I might need at night. I then put everything else in my pack, put the pack cover on it and have it directly under my hammock under the tarp. This almost always keeps everything dry unless water happens to run under the pack. But even then only the straps and back panel can get wet this way.
Comment: Building a heap of wood on which to put your pack under you hammock also helps to protect it from water running on the ground
Comment: @Shawn - Good tip!
Answer: They tend to wrap around you. It's hard to roll over in them. Heat loss can be a disadvantage too, but I live in the tropics so that is an advantage. Where I live it can be hard to find trees.
Answer: My personal problem with hammocks in general is my hips aching after an hour or so. I sleep on my side when in a bed, instead of my back, meaning I wouldn't be sleeping in a comfortable position on a hammock, thus preventing sleep and then tiredness in the morning. Camping provides no guarantee that you will find a place long enough to put a hammock that doesn't fold in on itself, either, leading to hip and back problems. Stiff hips would make the hiking harder the following day. If having your feet elevated to reduce swelling is more important than sleeping on your side, then it may not be as bad of an idea.
Comment: Next time try a South American hammock, which allows you to sleep on your side as you would in a bed, with absolute comfort.


MySQL Workbench HTTP tunnel

Question: Is there way in MySQL Workbench to connect to a database via HTTP Tunnel?
I've used HTTP tunnel for a while with Navicat and I would like to connect on same way to a remote databases with MySQL Workbench.
Thank you in advance
Answer: There's no reason why you shouldn't be able to set up a tunnel to do this.  Once you've established your connection, simply connect your MySQL Workbench to the local port that you've tunnelled to your remote server.
Obviously you'll need to be running to appropriate tunnel server on the remote-side to be able to accept your connection and establish the real TCP connection with the MySQL server.
Answer: Navicat probably uses a PHP script hosted on a web server to work via an HTTP tunnel, if it works like similar products. MySQL Workbench doesn't have that feature as far as I know. You'd have to tunnel via SSH as Steve Mayne suggests.

MySQL Workbench HTTP tunnel


What are overtones?

Question: Can someone please explain what overtones are and why they are important? I read a lot on the web about them but didn't understand. Also how can they be used when writing for orchestration?
Comment: Seeing as the question asks how they can be used in composing, iit might be good for an answer to address the use of natural & artificial harmonics on stringed instruments as a performance technique.  (I'm not a string player, so I probably shouldn't do it myself.)
Comment: @MichaelSeifert: e.g. pinch harmonic: https://en.wikipedia.org/wiki/Pinch_harmonic
Comment: Very helpful video: https://www.youtube.com/watch?v=i_0DXxNeaQ0
Answer: What is an overtone?
When you pluck a guitar string, there are a variety of ways it could vibrate1:

Each vibration will produce a different pitch, because they have different frequencies. For example, the top-left corner has the lowest frequency because it has the smallest number of crests/valleys--its crests are highly infrequent.
In most cases, when you play an instrument, the pitch we hear is the one with the lowest frequency. In other words, we hear the pitch produced by the top-left vibration. But when we listen a little more closely (as you've probably done), we can hear higher pitches being produced from the string at the same time. That's because the string isn't just vibrating with the lowest frequency. It is also simultaneously vibrating with some of the higher frequencies shown in the image above. Those higher frequencies are what folks often refer to as the "harmonics."
So in essence, the "harmonics" are higher pitches/tones that occur when you strike a string, blow air through a wind instrument, etc. They are produced because strings, air, etc. don't vibrate in simple, singular ways. Rather, they vibrate with many different frequencies at once, producing a combination shape like this2:

While it's true that the string vibrates with all of these different frequencies at the same time, it should be noted that the harmonics occur in varying strengths/intensities. In many cases only the first few upper harmonics are audible at all, and the others simply aren't produced or are too faint to hear. To test this, go to an acoustic piano and very gently depress the C5 key. Press down so gently that it doesn't create a sound at all when the hammer strikes. While holding down the C5 key, quickly strike and release the C4 note. What you'll notice is that the C5 string continues to ring out even after the C4 string is muted. The reason this happens is: the C4 string vibrates with its fundamental frequency, but it also vibrates with its 2nd harmonic, and the 2nd harmonic is C5. So when C4 vibrates, its 2nd harmonic excites the C5 string through a phenomenon called resonance.
Harmonics are important for many reasons. To name a few: they create an extra harmonious sound when certain chords are played. Piano hammers are placed in specific locations to avoid exciting dissonant harmonics. They are used by some brass instruments to reach notes that wouldn't be available without harmonics.
To clarify the terminology: the lowest frequency produced on the string/in the air is called the "first harmonic" or the "fundamental frequency." That's the frequency we predominantly hear. The higher harmonics (those above the first) are the extra notes that we hear ringing faintly with higher pitches.
1:https://en.wikipedia.org/wiki/File:Standing_waves_on_a_string.gif
2:http://ccnmtl.columbia.edu/projects/sonicg/terms/harmonic.html
Caveats
This description presents a simplified model, which is fairly accurate for most instruments. In reality, harmonics and overtones are two different things. "Overtone" has a broader meaning: "any higher frequency above the fundamental which is simultaneously produced." To qualify as a harmonic frequency, there's an extra condition: "any higher frequency above the fundamental which is an integer multiple of the fundamental frequency."
So "overtone" is an umbrella term, and there are two types of overtones: (1) "harmonic" overtones (which are integer multiples of the fundamental frequency) and (2) overtones that aren't integer multiples of the fundamental frequency (I'll call these disharmonious overtones). Everything I've discussed above has been about harmonic overtones. This is a fine way to answer the question, I think, because in the case of most instruments, the overtones deviate only slightly from the true harmonic frequencies. So in many cases, the overtones are close enough to be considered harmonic frequencies. The higher overtone frequencies may not be exactly twice the fundamental frequency, or 3x the fundamental frequency, but they're pretty close.
For some other instruments, though, the overtone frequencies will differ more dramatically from the true harmonics. For example, on timpani, the first overtone is 1.6 times the fundamental frequency. This dissonance is usually small, though, and many instruments are designed to minimize it.
Comment: On the subject of harmonic vs. disharmonic overtones, instruments that have an effectively one-dimensional sound-producing mechanism (eg. a violin or a pipe organs) tend to produce harmonic overtones, while instruments that are two-dimensional (eg. drums) tend to produce disharmonic overtones.
Comment: @jdjazz - I'm pretty sure there's music written which uses this sort of effect, ('harmonics on pno') but can't remember who did it.
Comment: This is one of the reasons keyboards sound so different than real pianos. They're very subtle, and I find more felt than heard, but they do exist and add to the personality of the instrument.
Comment: @dtldarek Truly, those sorts of considerations would be what separate the wheat from the chaff when it comes to synthesizing piano (and other) sounds. And if they inspire their code off of modern (and historic) piano construction techniques, I imagine they would be capable of creating very realistic sounds. However, the fact remains that they can miss something, and physics cannot forget.
Comment: There's a small caveat about harmonics, in real life with real strings harmonics are not exactly at integer frequency ratios but actually a bit higher due to string stiffness. They're still considered harmonics but aren't at integer ratios, they drift upward proportionally with the square of the frequency ratio. When you get the string stiffness of a bell though they shouldn't be considered harmonic anymore of course.
Comment: The wikipedia article on Inharmonicity covers it well, and according to it bowed string instruments are perfectly harmonic unlike say guitars or pianos https://en.wikipedia.org/wiki/Inharmonicity
Comment: 200Hz doesn't correspond to a note in standard concert pitch. A more real world example (relating frequencies to note names) would be 220Hz=A3, 440Hz=A4, 660Hz=E5, 880Hz=A5, 1100Hz=C#6.
Comment: @LoveIsHere, what you've said is correct. Many harmonics occur at once when you pluck a single string. The string vibrates with all of these frequencies at once. But they occur in varying strengths/intensities & only the first few are audible. To test this, go to an acoustic piano & very gently depress the C5 key. Press so gently that it doesn't create a sound at all. While holding down C5, quickly strike & release the C4 note. The C5 continues to ring out even after the C4 is muted. The C4 string's 2nd harmonic is C5. When C4 vibrates, its 2nd harmonic excites the C5 string through resonance.
Comment: @jdjazz  cool!!!!! will try it
Comment: 'They are used by some brass instruments to reach notes that wouldn't be available without harmonics.'   I'm trying to think of a brass instrument that DOESN'T use this technique.   Maybe some primitive one-note horns like a shofar.
Comment: @LevelRiverSt: this is only correct for "harmonic" tuning. In the temperate tuning most people use today the note frequencies do NOT line up exactly with the harmonics. For example the temperate C#6 is actually 1108.7 Hz. Small difference but it gets larger as you approach the diminished 5th, i.e. Eb vs D#
Comment: @Hilmar, I don't think tuning has anything to do with whether the modes are harmonic. I believe harmonic literally means "an integer multiple of the fundamental frequency."
Comment: @jdjazz Practically I guess not, but in theory it might – I would expect a drum tuned incorrectly so that only one diagonal is tight would behave more like a string and have more harmonic overtones. In a piano these differences are perhaps negligible, but surely they exist too.
Comment: @corsiKa Not the only one, there are some really cool examples [here](https://www.pianoteq.com/pianoteq6#pane_sound).
Answer: Overtones are harmonics, or upper partials; extra notes which sound when a fundamental note is played. The words are almost synonymous, but not exactly.
When a string is played, or a note blown, the loudest sound we usually hear is the fundamental - the one we would sing back, or use to identify what the note is. It has, to greater or lesser degrees, other notes that can also be perceived. The first there is an octave above the fundamental, the next a perfect fifth above that, and the next is two octaves above the original. From then on, the harmonics come along at smaller and smaller intervals, usually quieter as they go on.
Each instrument has a different mix of these upper partials, which actually gives it its unique timbre - tone. Violins are rich in them.
A simple way to find them is to use a guitar. By touching the string while plucking it, harmonics can be played. Touch exactly 1/2 way along the string gives the first (octave). 1/3 of the length gives octave and a fifth, 1/4 gives the next octave. Carefully working out exactly where along the string will give 1/5, 1/6, etc.
Bugles use the harmonics to produce all of their notes, as when the embouchure is tightened, higher notes from the harmonic range are made.
Answer: Any sound or other vibration produced by a process that repeats perfectly at some frequency f by be decomposed mathematically into a combination of sine waves at frequencies that are integer multiples of f.  Sounds produced by processes that don't repeat perfectly can be decomposed into sine waves, but they won't all be multiples of a common frequency.  In practice, many instruments produce vibrations that don't repeat quite perfectly, but are close enough that they can be decomposed into waves that are mostly multiples of a common frequency or very close to it.
Some natural processes that produce sound have obvious mechanisms that will produce multiple frequencies.  A plucked string, for example, will have many resonant modes as discussed in another answer, but other instruments may not have any obvious means of generating overtones.  A kazoo, for example, will produce many overtones even though it has no natural resonance at any of the frequencies involved.  In many cases, the effect may be modeled by simple harmonic distortion [such a model could be used with a kazoo].
If a device that produces simple harmonic distortion is fed a sound consisting of one or more frequencies, every frequency it produces will be the sum of integer multiples of the input frequencies.  For example, if a distorting amplifier were fed a combination of 200hz and 250Hz signals, each frequency in its output, in Hz, would be some multiple of 200 plus some multiple of 250.  All such frequencies would be multiples of 50, so the output would be some combination of multiples of 50Hz.  If something like a kazoo is fed a combination of frequencies that are all multiples of 440Hz, it will output will likewise consist of such frequencies.
Most musical instruments contain some resonating components which produce natural harmonics in aforementioned fashion (like a vibrating string) but also contain other components which introduce distortion.  For example, the top of a violin changes shape somewhat as it vibrates, and this will introduce harmonic distortion which adds frequency components beyond those generated by the string itself.  For instruments which are only used to play a single note at a time, such frequency components will be multiples of the note's fundamental pitch, so such distortion will often be pleasant.  Nonetheless, harmonic distortion often forms a key part of what makes various instruments sound as they do.
Comment: Overtones technically divide into two categories: harmonic overtones and other overtones that aren't integer multiples of the fundamental frequency, and I think this is an awesome job of addressing the second case. In the final paragraph, you've described how, "for instruments which are only used to play a single note at a time, such frequency components will be multiples of the note's fundamental pitch, so such distortion will often be pleasant." But do these frequencies still qualify as distortion of they're *harmonic* partials/overtones?
Comment: Most single-voice instruments produce waveforms that are close to being perfectly repetitive.  Perfectly repetitive waveforms tend to sound dull and lifeless, but some slight imperfections add warmth.  Most single-voice instruments' sounds will be dominated integer multiples of the fundamental, even though they contain some other sounds as well.  Power chords sound good a on a distortion amp because the three notes' fundamentals have a 2:3:4 ratio, so all multiples of those frequencies will be a multiple of a frequency an octave down from the lowest.
Comment: Ordinary chords generally sound bad on a distortion amp because the frequency ratios of 64:81:96 yield a variety of frequencies at somewhat arbitrary multiples of 1/64 of the lowest pitch.  If one detunes the guitar so that the third of a chord is a bit flat and the ratios become 4:5:6 the resulting chord sounds pretty cool, but unless one uses a custom fretboard that will only work for chords of one shape.
Comment: @supercat, A pure sine wave is boring, but the timbre of an instrument comes from things like which harmonic overtones are emphasized and the spectral envelope (especially the attack). When asked what overtones are, what's the reason for focusing on disharmonious overtones if they contribute very little to the sound of an instrument?
Comment: @jdjazz: The "integer overtone" model of sound is good enough to offer useful understanding and insights, but deviations from it form a big part of what make many instruments sound "interesting", especially on longer notes.  To a significant degree, the perfect integer overtones define the "instantaneous" timbre of an instrument, while imperfections represent how the timbre changes over time, but that viewpoint ignores the fact that many instruments have multiple resonant modes that aren't quite perfect integer multiples but don't change much with time.
Answer: The existing answers are great for technical explanations but might be missing something from the compositional (orchestration) standpoint. What you need to learn about is how different combinations of instruments and tones can sound good together because they reinforce each other (consonance) or interfere with each other (dissonance).
This happens at a pitch level according to the harmonic series, such as
C1 - C2 - G2 - C3 - (E3*) - G3 - (Bb3*) - C4 (etc.)
*These pitches are not exactly "in tune" to a Western ear because we use a scale in which the frequencies are adjusted (tempered) to allow us to play in multiple keys and create major, minor and other modes - which would not happen if we used exact frequencies.
On a variable pitch instrument like a violin, fretless bass, trombone, synthesizer, or the human voice, you can produce notes that exactly correspond to the harmonic series for the the fundamental pitch (C1 in the above example). Most other instruments can only be played at certain pre-determined pitches according to the physical capabilities of the instrument, although with wind instruments the performer can slightly vary the pitch (i.e. intonation) with embouchure and breath control. The instrument as a whole can also be tuned to a given pitch and keyboard instruments (piano, organ) have to be tuned in advance.
Generally, the more skilled the performer, the better they are at playing "in tune" with themselves and others. As a composer, then, you can write music that utilizes these frequency ratios to create consonance or dissonance according to what you are trying to achieve. There is a tendency to associate dissonance with negative emotions and consonance with more positive ones, although this is not a hard and fast rule.
That's why usually you don't have two low notes close together, for example, because they produce overtones that interfere with each other and create an ugly sound.  If you do create a dissonance, be sure to do it intentionally and not by accident.
Lastly, as mentioned already, instruments have a timbre which contains the fundamental note and various overtones. This is not as easy to control and actually forms part of the characteristic sound of the instrument.  However, you also have to be conscious of how the timbre / overtones of one instrument will interact with another one. See this link for some examples of good /bad instrument combinations (in the opinion of that author).
Hopefully this helps with the "why it's important" part from a composer's standpoint.
Answer: Any note, other than a pure sine wave, heard in an anechoic chamber, will contain additional frequencies to the fundamental one.  The laboratory demonstration of a string vibrating as a whole, in halves, thirds etc. is an ideal case.  In real life, a string will not possess absolute uniformity and negligible mass. It will also be attached to other structures with their own resonances.  Therefore (and fortunately, for making interesting sounds) many of the overtones will be shifted from their theoretical place in the 'harmonic series'. An extreme case is the church bell, which has a strong overtone a major 7th above the fundamental!
But, broadly speaking, instrumental sounds consist of a mix of frequencies corresponding pretty closely to the harmonic series.   How can this be used in orchestration?
Well, you could borrow the trick organ builders use to produce the sound of a 32' pipe without actually having to build such an expensive and bulky item.  Two ranks, an octave and a twelfth above the desired pitch, can cause an interesting effect.  Read about it here:
http://www.mmk.ei.tum.de/fileadmin/w00bqn/www/Personen/Terhardt/ter/top/acbass.html
The same technique could be used in instrumental scoring.  Write a pair of flutes, a perfect 5th apart.  Can you hear the 'virtual' lower octave in this example?

Acoustic phenomenon or perceptual one?  How far out-of-tune can the notes be before the effect stops working?  (How far out-of-tune do ANY notes have to be before they lose their harmonic function?)  We're getting into a a fascinating area here...
Answer: Simply put, overtones are higher frequencies that are played at the same time as the tonic. (Likewise, undertones are played at the same time, but at lower frequencies than the tonic.)
Overtones and undertones make an A 440 sung by a human sound different than an A 440 played by an oboe, or by any other instrument.

What are overtones?


Why did Vera kill this character?

Question: In Mr. Robot Vera had an affection for Shayla, and the only one causing the problem was Elliot. So, why was Shayla killed even before Elliot tried to free Vera?
Answer: Vera treats Shayla like she's his property. He even tells Elliot in an earlier episode not to touch her because she belongs to Vera. She's a piece of his empire. When Elliot tries to use Vera's money against him as a bargaining chip (by hacking Vera's brother's cell phone), Vera decides to burn it all to the ground and start over. Vera doesn't have any more use for Shayla other than to extort Elliot into breaking him out of prison. She doesn't need to be alive to do that, so killing her is simpler than holding her somewhere.
Answer: Vera is trying to make a point, that he's not the person to be messed up with.
Vera could still keep Shayla alive and give her back to Elliot when he's out of prison but he killed her because he wanted to hurt Elliot badly, teach him a lesson that he made a mistake by sending Vera to prison.
What really surprised me was that Vera leaving Elliot alive, even though Elliot was the reason for Vera being behind prison bars, Vera liked him, in previous episodes Vera found that Elliot is fearless just like him.

Why did Vera kill this character?


I have 3 users on my computer. The internet works on 2 of them but not the third. How can this problem be sloved?

Question: I have 3 users on my computer. The internet works on 2 of them but not the third. Downloading Firefox did not work. What should I do?
Comment: Citation needed \ MOAR INFO. :)
Answer: There could be multiple reasons why this is happening.  There should be a basic troubleshooting scheme that will help you get the correct answer.  Was Internet Explorer the first browser you tried and this happened in?  Have you tried Chrome or other browsers with the same trouble?
On the user that the internet isn't working (i.e., logged in as that user), go to the Control Panel and then open up the Networking Connections window.  Take a look at the current connections.  Are they connected?  Do you see LAN or Internet in the list, among other items?  Double click the LAN icon and see if there is traffic.
If there is traffic, then you may have a browser issue.  If this is not showing packet transfer or seems disabled, go to the the Control Panel again and double click System and click the Hardware tab and then the Device Manager button.
Find in this list the Network Adapters and double click.  Be sure this is enabled for this user.  If it is, then go back and try the Internet again and see what happens.  If it's not, enable it and try the browser again.
If none of this works, I would consider backing up the user data and, if possible, create a new user account, test for Internet connection and then convert the user to that account.  This can be done relatively painlessly in Windows.
It really depends on how much work you want to do to fix this problem:  a whole bunch of troubleshooting or create a new account.
Comment: You don't necessarily need to migrate to a new account; you can probably just rename their profile folder and let Windows create a new one next time they log in.


Should I run if I see wild dogs?

Question: Feral dogs appear to be dangerous. Should I be running if I come across one, or should I stand fast and defend myself? They are a social animal, so they will be in a pack almost all the times.
Comment: Running is exactly what they want you to do, that's how they hunt, they run their prey tired and then finish them off after they can't run any further. Your best chance is to act aggressive and fight them off.
Comment: where are you encountering these wild dogs?
Comment: We tend to get a lot of discussion on outdoors.SE that's along the lines of "I'm scared of bears/dogs/snakes/spiders, so how can I kill them, scare them away, vaporize them with laser beams, (etc.) so they can't get me?" A wild/feral/abandoned dog is a sentient being that is trying to survive. Obviously I don't want to get killed by a pack of them, but realistically, a dog's prey is stuff like rabbits and squirrels. Although it's been known to happen that wild dogs kill humans, it's not common. A good outcome is one in which both dogs and humans are OK.
Comment: @ShemSeger Can you provide a reference that feral dogs are eating homeless people in Detroit...  That sounds like more of an urban legend than anything else to me. The closest I found with a quick web search was a case of [a guy getting mauled while feeding someone else's dogs](http://www.mlive.com/news/detroit/index.ssf/2014/10/the_dogs_started_attacking_and.html).
Comment: @MasonWheeler This is heading in a direction that isn't helping the OP so I'll say this and let it go. Firstly, Russians were able to [domesticate foxes](https://en.wikipedia.org/wiki/Russian_Domesticated_Red_Fox) in under a century. IMO calling a feral cocker spaniel in Detroit a wolf is like calling humans a monkey. There is some scientific basis, but the comparison is outrageous. Secondly if packs of feral dogs were actively hunting the homeless in warehouses in Detroit that would be national news.
Comment: @Gerhard: [Factually incorrect](https://en.wikipedia.org/wiki/Wolfdog), as wolves and dogs can still interbreed and the offspring breeds true.  Notably, half-wolves were used in the breeding program that created the German Shepherd breed, but wolves have been known to interbreed even with some of the least "wolf-like" of dog breeds, such as poodles.  This works because *dogs are wolves.*
Comment: I'd go for a thrown rock or a sturdy stick. I've seen even an aggressive dog shy off when I waved a stick at it.
Comment: I visited Detroit once with a friend. He wanted to show me all the cool abandoned buildings he used to explore when he lived there. His one word of caution was, "Watch out for dogs, there are packs of wild dogs that live in these abandoned factories and warehouses that will eat homeless people..." The danger is real.
Comment: This suddenly reminds me of a war story of my grandfather's. He was in the Algerian desert on a demining mission when he ended up having to spend a night alone, a pack of wild dogs or fennec (I can't remember) came to attack him, he turned on his back in a submissive position, thinking he was going to die, they came over to smell him but let him alone. I believe I've read this kind of thing happen to others. It's probably a well-known behavioural pattern in pack animals.
Comment: Learn more about dogs' body language, because you first need to assess whether you are under attack or not if you are being approached by dogs. Keep in mind that barking is not necessarily aggressive, a barking dog running towards you while wiggling its tail means that you are not under attack. Additionally, you can still avoid initiating a fight with a growling or even a charging dog if you act confident. Before acting, try to assess the mood of the beast and don't forget its probably scared of you, too.
Comment: @MasonWheeler Are you talking about stray dogs in Detroit? It feels to me like you're quoting out of *[The Island Of Doctor Moreau](https://en.wikipedia.org/wiki/The_Island_of_Doctor_Moreau)*. I agree that the dogs aren't pets, but it seems like hyperbole to say they're practically wolves.
Comment: @Erik: They're not "practically wolves", they are *literally wolves.*  That's what a dog is: a sub-species of wolf that's been selectively bred over millennia to be a bit cuter and a bit less hostile to humans.  But most of the "man's best friend" veneer is pure nurture; by nature they are still wolves and without being raised by humans they very quickly turn just as vicious.
Comment: They turn nearly as vicious as hungry people.
Comment: Plenty of wild/feral dogs where I jog, I usually grab a large stick when I approach the area and stand ready to use it, which I do sometimes. However this one time there were a dozen of them: I ran and climbed up a tree. I stayed up there about 20 minutes, then they got tired of barking and left. We might have been best friends, I'll never know.
Comment: Throw food, if you have it.  Climb a tree, or something else that dogs can't climb.
Comment: @ShemSeger is right.  These are not man's best friend; they're *wolves* that have reverted a good portion of the way back to their primal state in the absence of the order and structure provided by human companionship.  Deal with them accordingly.
Answer: Wild dogs can indeed be dangerous, and packs can be extremely dangerous.  You do not want to take on a pack of dogs if you can at all avoid it, and running is often a particularly bad idea.
I suggest starting with the basics: try to keep the dog calm and don't try to intimidate it.  This means:

Don't make direct eye contact, and remember that sunglasses look like large unblinking eyes.
Don't smile (it bares your teeth, which can be similarly threatening).
Don't approach it, and don't make sudden moves or shout at them.
Do keep an eye on it, and you can try calmly talking.

Above all, don't "act like food".  Turning your back, acting afraid, or trying to run away will show weakness and probably trigger their prey drive.  Your job is to act bored until they aren't interested in you, then to slowly back away.
If they are still acting aggressive and you have the time, prepare for an attack.  Quickly see if there's anything you can use as a weapon.  If you have a jacket, wrap it around your weaker forearm.  If you have a pack, ready it to fend them off.  Yelling for help may be a good idea, in case others are nearby.  In an attack, two things are very important:

Protect your face and neck.
Do not let yourself be taken to the ground*.

A dog can move quickly, and trying to hit the dog will likely be counterproductive (unless you happen to have a bat or stick).  Instead, try to keep something between you and it, even if it's just your forearm.  Here is where things start to get ugly.  If it latches onto your arm, remember that you still have your other arm and both legs.  Be careful to keep your balance, and don't worry about trying to free your arm immediately; the one bright spot is that its mouth is otherwise occupied.  Instead, focus on attacking the dog.  This is an excellent time to deploy pepper spray or a knife.  Absent that, shoving a stick or even your arm down its throat may be appropriate, or strikes to its throat and eyes.  (At this point, you are way beyond a newspaper swat to the nose, and there's a good chance you may need to kill it.  Hopefully there's a good chance you outweigh it.)
*If you do get taken to the ground, protect your neck and roll around quickly.  Letting the dog get a solid bite on your arm (see above) will be better than letting it get hold of your throat.
When dealing with a pack you're in significant danger.  A defensible location and weapons will be very helpful.  I suggest a fighting retreat; turn your back and they'll take you down, and they'll probably try to flank you as well.
Finally, if you survive an attack there's a good chance rabies may be in play, so get yourself to a hospital immediately.
Comment: If the dogs are used to humans, crouching down and pretending to pick up a rock, then cocking your arm as if to throw it (or just assuming the throwing position in a pinch) can work to send them away. This is the recommended approach for street dogs in the Pacific, for example. (The ones in Samoa are listed as a hazard on the Canadian government web site, for example.)
Comment: @ab2 - Only if you're a faster runner than the other guy...
Comment: +1 for the first 4 points, and the acting 'bored' - acting bored / ignoring a pet dog is exactly how you get it to stop bad behaviour (like barking, nibbling, jumping up etc) there's no reason this wouldn't apply to their wild counterparts. Just a point that most wild dogs and wolves spend most of their time asleep (or lounging around doing very little) - unless hungry, need the toilet etc,as they sleep until something interesting happens, just like pet dogs. If you see them out and about likely very well rested.
Comment: We are not distinguishing between wild dogs, feral dogs and strays.  Feral and stray dogs are both "Canis familiaris" and have genetic behavior that predisposes them to understand (to some extent) humans.  Wild dogs, e.g., the African wild dog (Lycaon pictus), or the dingo (Canis lupus dingo) have a different genetic heritage than C.f relative to humans.  (Although the dingo may be descended from semi-domesticated dogs.)  Can a doggy person say something about the different threats these different canids might pose?  Or, should thIs be a separate Question?
Comment: On more than one occasion I've treated charging snarling dogs with praise and called them towards me, "Here boy! Goooood doggie! That's a good boy, come here, come her let me pet you!" Do the actions and make the faces too, I typically get one of two reactions: most often they just figure you are probably a friend so they approach you and want pets and scratches. But the funniest reaction is always the look of confusion they get when you respond to their aggression completely opposite to how they expected you would. Then they kind of slump off annoyed and dejected, "Rrrr... ruff. Whatever..."
Comment: Trekking poles are particularly useful as well.
Comment: @Morningstar How is assuming a pack of feral dogs might attack you an evil attitude? It's simply erring on the side of caution, which is a vital survival trait.
Comment: This is easily some of the best advice I've seen on this subject
Comment: @ab2 A dog born in human environment, which got his food from a human in his first months, _never_ ever forget it and wants his this "golden era" back. _Every_ feral dog knows very well, how good was it for him as he could live with a human, in a warm place, with regular feeding. A dog born feral is exactly the opposite, for them we are deadly enemies or food. But this second group is very, very few, because hunters have free license to shoot any number of feral dogs.
Comment: @ab2 Generally speaking I would say yes your odds improve for preventing an attack, and surviving an attack for every person you add to your group. Unless of course that second person is a small child or takes Taegost's advice...
Comment: Gee, not everyone shows their teeth when smiling.
Comment: Do the odds change markedly in your favor if there are two of you?
Comment: I also read somewhere that pulling your jacket above your head while still wearing it will make you bigger for the dog.
Comment: I walked into Taegost's comment!  what I meant was, would the dogs be much less likely to attack two (or more) people than one?
Comment: @ab2 If you find a pack of feral dogs, nearing you, they are probably fighting for their lifes, they are feeling _very_ _very_ _badly_, their instincts say them very well that they are in life-threatening danger, and they want food and help from you. It is not sure, but probable. Handling them as predators wanting to kill you is a very evil attitude.
Comment: "remember that sunglasses look like large unblinking eyes." so should you wear sunglasses or not, then? do they look like making eye-contact?
Answer: To the question of whether you should run from a pack of dogs that may be aggressive, the answer is an unqualified NO!.  As to what you should do, the answer is a bit more complicated.  In the vast majority of cases, dogs won't attack you without provocation.  As always, assume the best but prepare for the worst.

The basics:
Be Prepared:
Prevention is better than having to deal with an attack.

Carry a sturdy hiking stick.  A good, thick wooden staff is better than trekking poles, but poles are better than nothing.

Consider carrying pepper spray/mace/bear spray.  Very few healthy dogs will pursue a confrontation after being pepper sprayed. Another option, although they are less common and a bit harder to find, are Bear Bangers.  Bear bangers are basically just fireworks that can be launched from a handheld, pen-like launcher.  They make a loud screeching sound, then a loud bang, and they emit a bright flash, smoke, and sparks.  The idea is to bewilder and frighten wild animals before they get close enough to hurt you.

Have a good, sturdy knife handy.  If it folds, make sure it has a sturdy locking mechanism so it doesn't close on your fingers when you try to use it.  A 3-4 inch blade is sufficient, but of course, a machete is even better.  However, very few people are in the habit of carrying machetes on pleasure hikes.

Know the area.  Are there wild dogs here?  (As a follow up, if there are wild dogs, why haven't you called animal control?)  Are there safe places to get away from a potential confrontation?  Many things will fit this purpose - an easy-to-climb tree, rock, antenna, lookout tower, etc, that dogs can't climb;  an unlocked car;  an unlocked business, home, or cabin;  even the back of a pickup truck will do.

Silly as it might sound, it isn't necessarily a bad idea to carry dog treats, if you are sure that wild dogs are present in the are where you will be hiking.  The best way to turn a threatening dog into a non-threat is to give him something to eat while you make yourself scarce.

Carry a means of communication that will definitely work - once you get up a tree, the dogs can't get you, but what if they decide to wait you out?  It's not likely to happen, but it is possible.  In most places, a charged cell phone will suffice.  If you're hiking in an area with poor reception, a satellite phone or emergency radio (know the local emergency channels/frequencies), or, as a last resort, a signal whistle or distress beacon.

If you bring dog treats, they can go in your backpack, but the phone, mace, and knife should be on your person at all times - on your belt or in your pockets.

As always, let other people - people who aren't in your hiking party - know where you're going, when you will get there, and when you expect to get back home.  If no one knows you're missing, no one will look for you.

Know the warning signs:
Don't confuse a curious or playful dog with a dangerous one.

Most dogs are not aggressive, but, rather, just curious or defending what they perceive as their territory. Thus, to avoid unnecessary conflict, it is important to be able to tell if a dog is just playing or is being truly aggressive. While some breeds have been singled out as being particularly vicious, any mid-size and large dog breed can be dangerous, so do not ignore warning signs because you think a certain breed is harmless or friendly. Watch for common signs of aggression (and non-aggression):

Growling, snarling, and baring teeth are obvious displays of aggression and should be treated as such.
An angry dog may show the whites of his eyes, especially if these aren't normally visible.
Pulled-back ears laying flat against the head are a telltale sign of aggression, whereas normal floppy or elevated ears usually signal a dog's nonchalance.
If the dog approaches you with its body relaxed and with a sloping curve in its midsection, the dog is probably not going to attack.
A dog whose body is tense, straight and stiff (head, shoulders and hips aligned) could mean business.
A loping gait means the dog is playful and checking you out. An even, steady run means the dog may be dangerous.
Source

Once a confrontation begins:
You might say that the best approach consists of the following steps:  Stay Calm, Ignore, Placate, Intimidate, Repel, Fight Back, and Last Resort (for this section, I am borrowing much from these two articles.  Use each step in turn if possible, and if any step works, that's the time to back away (see "exit strategies", below).  If any step fails to have the desired effect, move on to the next one.

Stay Calm.  Don't panic.  There is some truth to the old adage that dogs can smell fear.  Unless you are a few feet from a safe haven (e.g., an unlocked car, house, business, easy-to-climb tree), don't try to get away, and above all else, don't run.  Running will trigger the predatory instinct in the dogs, and virtually guarantee an attack.

Ignore.  Put your hands at your sides.   Extending your arms could be perceived as threatening, and it opens them up to a bite.  Roll your hands into fists to protect your fingers. Put your side to the dogs, not your face or back, but keep the dogs in your peripheral vision.  It should be seen by the animals as an "I'm neither scared of you nor hostile to you;  you just don't matter to me" signal.  They may approach you, even sniffing you.  Let them.  Don't react.  The best case scenario is that they'll turn out to be friendly and seek positive attention, or at least decide you're neither a meal nor a threat and simply walk away.  If this doesn't have the desired effect, move onto placation.

Placate.  Don't immediately engage the dogs with hostility.  Try to distract them first.  Offer them something else to focus on.  If you have treats, use them now.  If you don't, try, almost anything else - a water bottle, backpack, whatever.  Pick up a small stick, if you have nothing better - if the dogs know people, they might take this as an invitation to play.  If so, you just found yourself a pack of friends.  If not, throwing  stick might still distract them.  If you lose your backpack to the dogs, remember - however much it sucks to have your possessions torn up by dogs, it's still better than having them tear you up.  If it doesn't work, intimidate.

Intimidate.   Keep in mind, although this is now your best option, it could very easily escalate the problem.  Things are getting serious.  Face the dogs, but avoid eye contact.  Say something like "BACK OFF!" in a firm, deep, confident voice.  If this fails, try to repel them.

Repel.  If the dogs persist in signs of overt aggression - growling, snarling, baring teeth, etc - now is the time to deploy the "ranged weapons" - mace/pepper spray/bear spray.  This is probably going to end the confrontation in a hurry.  If it doesn't immediately set the dogs to flight, spray again.  Target all the dogs that are showing aggressive behavior, but pay special attention to the boldest, most active animal(s).

Fight Back.  If they attack, fight back.   Do not instigate the fight.  Only resort to violence if they do so first.  Now you can - and should - start to yell, hopefully in a loud, deep, commanding voice.  This might intimidate the dogs, and if it doesn't, it will hopefully attract the attention of anyone in the area.  Don't scream or shriek, as this will probably just make things worse.

Abandon any sense of mercy or compassion, because your life is on the line.  They're trying to KILL YOU, so you have to kill them first, or hurt them bad enough to make them retreat.  Feel bad about it later.  It might be unpleasant, and as a dog lover myself, it pains me to write this as my sweet yellow lab lays sleeping beside me on the couch.  But you are fighting for your life, and a dead dog is better than a dead you.
Try to spot the most active, dominant animal, and focus on it.  It might be the literal "leader of the pack", and if you hurt it enough to scare it, the effect should spread through the entire pack pretty quickly.   Convince the alpha to retreat, and - at least in theory - the rest of the dogs will follow their leader.

Weapons. You're a homo Sapien.  You evolved to use tools and weapons, and this ability is the main reason your species is so dominant.  Use it to your advantage.  Try to fight by hitting the dogs with your weapons.  Start with the stick.  Swing for the back of the head.  It should stun the dogs.  If you lose the stick (or didn't bring one), use the knife.  Stab, stab, stab.  If you lose the knife, or didn't bring one, grab a good sized rock or stick and start smacking skulls.  If no rocks or sticks are available, you're stuck with close quarters, unarmed fighting.

Hand to paw.  You still have some advantages.

A.  You can kick and punch.  Kick throats, punch the backs of heads.  Do both to sensitive noses.  This is your method of choice with a large number of dogs, because it keeps the greatest possible distance between them and your vitals.  Against a large pack, stay on your feet as long as possible,
B.  You can't bite as well as they can, but you're bigger and stronger, and you have all the leverage and flexibility.  Dogs suck at wrestling.  If you can do so relatively safely, use your weight to your advantage by crushing the dog with your bulk.  Come down on their chests with both knees, as hard as you can.  Do it hard enough and you'll kill the dog, or at least wound it so badly that it is no longer a threat.  Obviously, the fewer dogs you started out against, the safer this technique will be.  With a large pack engaged in a fight, it might put you in greater danger by making your vitals more accessible.

Last Resort.  If you are overwhelmed and unable to stay on your feet, do what your instincts should be telling you to do:  duck and cover.  On the ground, pull your knees tight to your chest.  Tuck your head down, chin to chest.  Lock your elbows outside your knees, with your fingers interlaced behind your neck.  Now roll onto your knees, so your face iand stomach are both protected by your limbs and facing the ground.  Stay quiet.  Don't move or scream.  You're trying to keep teeth away from your soft spots - face, throat, neck, belly, and groin.  Your back, arms, and legs are there to take the brunt of the damage.  You are hoping that the dogs will quickly lose interest, and/or that help will arrive before it's too late.

Exit Strategies:
If and when you see an opportunity to get away - the dogs are calming down, losing interest, or being scared off - follow these steps (obviously, if you're already being attacked and get an opening to climb a nearby tree or something - without having to run more than a few steps - you should take it):

Back away slowly for as long as possible.  No eye contact or sudden movements.  Stay calm and try to appear confident.

Once you are a safe distance away, turn around and walk slowly towards the nearest safe area that doesn't require you to pass by the dogs.

If you're hurt, get to the doctor.

Call animal control or law enforcement.

Further reading:

ASPCA -  Predatory Behavior In Dogs

Humane Society - Dog Aggression

Walking.com - How to Avoid a Dog Attack

Martial Arts.SE Question on this subject

Personal Observations On Dealing With Dog Attacks - Prevention and If Attacked

BBC - How Do You Fend Off A Dangerous Dog?

Cesar Milan, "The Dog Whisperer", has some tips as well.  Some of them are very reasonable, but others strike me as potentially exacerbating the situation.  He seems to assume that you will have your own dog with you, and he furthermore appears to believe that this is usually a good thing, but I see a lot of room for it to cause much more serious problems - your dog may provoke a fight out of  a desire to protect you, and once the fight begins, you're basically stuck there, unable to get away - unless you're willing to abandon your own dog to be torn to pieces by the wild dogs.

Fighting aggressive dogs:  This article takes a slightly over-aggressive approach, but has some interesting pointers for the worst case scenario.
Comment: This is an excellent answer. It considers everything from the dog's perspective (decreasing any perceived threat). The only thing I would add (I used to raise and breed dogs, so learned a lot about dog behavior) is that after steps 1 and 2, if the dog is still interested, look briefly for a stick. Bending down to pick up the stick (or a rock) - as long as you're not near to the dog and facing it directly - is a perceived by a dog as an invitation to play (non-aggressive), which can diffuse a situation, and you get a stick to fight with if it doesn't.
Comment: @MorningStar - The answer addresses the worst case scenario, which is the information sought by implication in the question. In the (99%?) of the situations when the dogs won't attack, you don't need to know all this stuff. But you need to know it in the (1%?) that matters.
Comment: @MorningStar - My suggestion boils down to:  Figure out if there is a real problem, because there probably isn't.  Then try to ignore them, then try to interact positively, perhaps even playing with them, then try to scare them off if everything else has failed so far.  If that doesn't work, repel them without violence.  If, and only if, they attack you, that is when you should fight.   But that will almost never happen.  As someone who prefers dogs to people, I would never suggest being aggressive towards the most wonderful species on the planet.
Comment: Good answer. Mightn't the smell of the dog treats *attract* the dogs to you though?
Comment: Not from a distance, by any means.  Put them in a ziplock bag and you should be fine.
Comment: @MorningStar - you seem to have missed about 60% of the answer.  There's a section on how to distinguish between curiosity/playfulness and aggression, and the first several steps in the confrontation section assume that you won't be attacked and can handle the situation peacefully.
Comment: @MorningStar - Besides, the worst case scenario is the only one that needs to be addressed.  If a dog trots happily toward you, drops a tennis ball at your feet, and looks up with eager anticipation, wagging his tail, you know exactly what to do - pick up the ball and play fetch with him.  That situation is clearly not what the OP is asking about.
Comment: Your whole answer is about confronting the dogs. Meeting a pack of feral dogs, there is a 99% chance that they fear much more from you as you from them. Or, if they near you, it is because they want you to give them food, and not to eat you. Your answer completely ignores these possibilities and handles the dogs as predators trying always to kill any human. Even the bears aren't so dangerous for us.
Answer: I'd say the only circumstances where you could try to run is when a safe place is near (your car, some kind of shelter, a tree you can climb etc.), the dogs are already alert and running to you (otherwise you could just walk to the shelter without them noticing), and you can realistically make it to the shelter before the dogs do. Remember that dogs car run 2-3 times as fast as you can.
Running away from the dogs into nowhere is a stupid idea:

you're provoking them to chase you by running
you cannot outrun them in the long run
you're turning your back to them

Running towards the shelter when dogs are already near is also not advisable, you'll have better chances walking towards the shelter while still facing the dogs. Facing is very important, as the dogs will see that you're taller than them and ready to fight back, which will intimidate them to some degree and give you more time.
Comment: This is excellent survival advice. Running "away from danger" is a bad choice when dealing with predators (including human attackers), while running "to safety" can be the best approach. As you note, the key difference is a realistic assessment of your chances of getting away.
Comment: @MorningStar Avoiding dogs who didn't mean any harm is not a problem, while not taking aggressive dogs seriously enough is one. Remember how they tell you to pick strong passwords on the Internet, while 99% of the people won't be able to crack something as simple as `passw0rd`. You still have to take care of the remaining 1%.
Comment: A dog can run 100m in 6 seconds...
Comment: Your whole answer is about confronting the dogs. Meeting a pack of feral dogs, there is a 99% chance that they fear much more from you as you from them. Or, if they near you, it is because they want you to give them food, and not to eat you. Your answer completely ignores these possibilities and handles the dogs as predators trying always to kill any human. Even the bears aren't so dangerous for us.
Answer: So far all of the answers are assuming the wild dogs are actively hunting you or at least seriously considering attacking you. This might be due to the part of your question where you say:

... or should I stand fast and defend myself?

If the dogs appear to be actively hunting you then a controlled exit to a safe area as suggested by Dmitry Grigoryev is a good plan. If an attack is truly imminent, and you can't get to safety, then the advice offered by requiem is great for trying to deescalate the situation and survive the attack if deescalating the dogs doesn't work.
However I interpreted this question more as saying: "I see a wild/feral dog. Should I be nervous?"
That is a totally reasonable question. If that is what you're asking then I would say, generally you should be cautious and aware of the dog(s) but not nervous. You probably aren't going to be harassed by wild/feral dogs unless something else is going on. Personally I've seen wild dogs numerous times while out hiking and/or hunting1. Most of the time we just look at each other and go our separate ways. I've also encountered feral dogs while traveling in third world countries. These feral dogs caused my wife to get nervous at times, but we were never in any real danger of the dogs attacking us IMO. Honestly fleas were more of a concern with feral/street dogs that I've encountered than the dog attacking.
As such the appropriate response to the feral dogs and the wild dogs that I've encountered has always been to watch for signs that they are acting unusually aggressive, while carrying on business as normal. If the wild/feral dog is acting markedly aggressive then I would highly recommend requiem's answer for defense, if Dmitry's option of avoiding the fight via a safe shelter isn't viable.

1: This has been in the United States where coyotes/wolves have been hunted historically so it might not translate perfectly to regions of the world where wild dogs haven't learned to fear humans, if such a place exists.
Answer: In Mexico, I learned that the best way to deal with wild dogs was to squat down very briefly and pick up a small stone.  I never had to actually chuck it at a dog.  They skulked off quite quickly when they saw the movement that looked like the human was picking up a small rock.
Comment: I am living in Turkey, leaning down and pretending to grab stones works here as well. I have also seen that some dogs are afraid of the sticks in my hand. But on most cases I don't need it. When I stand my ground and make clear that I am not a prey, they change their minds
Comment: Which means, they didn't want to fight with you to kill. If they had wanted, they had ignored the stone and had simply attacked. You didn't present a real threat for them, you only gave a strong "go away" command, which they could have ignored if they wanted so.
Answer: Firstly wild dogs are not harmful if you are not doing any foolish in front of it.

SERIOUS BITES ARE RELATIVELY RARE, AND NO PARTICULAR BREED
  is more likely to be responsible for serious bites 1

This maybe bit scary, but sometimes doing nothing and just standing still can save your life. Animals focus on you more when you running.

Most importantly, the person should never run. A human cannot outrun a dog and, as already noted, many dogs respond to people, animals, and objects that are running or moving quickly by chasing, catching, and even biting. This is play for the dog, not fear or hostility, but serious injury can result. This impulse explains why bicyclists, joggers, skateboarders, and skaters are often involved in problematic encounters with dogs, whether as a result of bites or, more commonly, falls.

[1] The Problem of Dog-Related Incidents and Encounters - from the National Canine Research Council
Answer: I have couple tips for such situation:

Try to stand sideways to the dog if it is possible - I've heard about that in some National Geographic program - it's pretty neutral stand for dogs. In the same time try retreat very slowly
Try to climb somewhere dog can't reach You (if it is possible)
Don't be afraid; in most cases You're bigger and stronger and the dog is the one who's afraid in such situation and they can feel that You're scared

If any of those tips fail, then:

Try to pretend be bigger than You're actually are - take Your arms up, try growling and shouting to scare opponents
Use tools - backpack, pipe, trash anything that can be a separator between You and a dog; anything that You can use as a weapon or a shield

If confrontation will be inevitable:

don't be afraid to kick and punch - You're fighting with wild animal who probably want to kill You - You have to be faster,
target into sensitive points: nose, eyes (if dog will bite You and don't want to let go - put fingers into its eyes), reproductive organs, try to break its leg bones
Answer: There are 2 types of dog aggression you are concerned about here:

Territorial agression:
Most common situation, you are coming through a place they consider their turf. You ignored the "obvious" piss smell and are trespassing. They are not attacking you so much as defending and they are somewhat afraid but there is strength in numbers.

Do not run, that makes you a prey and they will come after you. The easiest way to deal with it is to back off slowly and they will let you go.
Unfortunately, sometimes going around isn't an option. An advice I was given by a good dog trainer was to ignore them and just keep walking.
I have been in that exact situation with 1-2 dogs many times and on 3 occasions with semi-wild dogs packs. With a few dogs, I have tried to just keep walking and it seemed to work reasonably except a few times where my nerves go the better of me and I started charging on them, causing them to back off a bit
With the dog packs (10-30 dogs), I didn't want to end up having to start fighting with several dogs already close, so I opted for a more aggressive approach. Can't say that my approach is the right one but it worked for me and I didn't get bitten - I was pretty scared though.
I kept walking forward giving them as much space as possible. They came snarling and started surrounding me. I quickly found who the pack's alpha was. I made myself as threatening as possible, raised my arms and marched on the alpha as if I was the one attacking. The alpha backed off and started circling, giving himself some space and all the other dogs held off to see how it was going to play out. I held my spot a few seconds and walked away. Of course the alpha was circling back and coming closer along with the rest, so I turned around and threatened the alpha again moving towards him a couple meters. He held his ground a bit longer then ran in a circle and I resumed my walk, slowly but surely getting through the area. Each confrontation getting a bit harder, but after several such confrontations, I ended up through on the other edge of their turf and going away, which is what they wanted in the first place: no intruder. Every one of my movement was slow as I didn't want to actually start a fight.
The main point here to keep in mind is that there is a very clear territory they are protecting and your goal is to get out of it without triggering predatory response.
In all cases, do not run away, and if you chose to walk down a dog, do NOT corner him. You want him to be able to create distance, or he will end up having to fight.
It's a stressful situation and it helps to remember that you are 2-3 times as big as they are. Sure, they have teeth and are a lot more athletic than most humans, but they don't know how weak you really are and they are scared, so you can effectively threaten them.

Predatory aggression:
They are hunting for a meal and you look like one. That's very unlikely unless you are running and show you are afraid.

I have never been in that situation and I think you are up *** creek if a pack of wild dogs decides you look tasty. That said, I think your best course of action is to identify the alpha and attack. Don't behave like a prey and they might turn tail if they feel they are hunted.
Obviously having weapons will help (spray, sticks, etc.) because you are in a fight.
Answer: You can't run from them, but...

They can't climb to a tree. You can.
They can't jump over a fence. You can.
They can't even break a single glass window.
Many of them fears if they see anything in your hands. They don't have any idea if this object is really dangerous or painful, or not.

But...

A dog see a human as a leader and a source of very happy things (warm, food, etc). It is imprinted into them since around 8000 years. It is a very-very last resort if a dog see a human as food. (Which is exactly opposite, as the bears do - for them, we are just moving food, just as a deer.)

Between stray dog and stray dog there is a large difference:

Most of them born in a human family, and learned as a small puppy, that humans are very, very important to get food, and they are also very strong leaders. After that, on a point of his life, he was thrown out, and although he survived it, he won't ever forget the "golden era" of his life. Such dogs won't ever attack you. They eat cats, mouse, shit, deers, and similar things.
A little bit of them didn't ever see a human. These dogs are practically unsocializable and need to be shot (or euthanized), because you are really food for them.
Move your hands and legs, and show them, how will you kick them, or beat them, if they come near. Imitate that you kick them, beat them, throw painful things to them. They understand the human body language very well (often better as we understand eachothers), but don't have any idea if you can realize the threat or not. It is much more efficient if they really see something in your hand, best if it is long, as a staff.

Most dog doesn't live too long free, because hunters have free license to kill any dog without an owner. Thus, the really stray dog, which hasn't ever seen human, is rare. There is another reason: even for completely feral dogs, knowing the human behavior is an important thing for the survival, but these knowledge can be get only with humans. Stray mother dogs can't explain this to their pups - the capability to transfer complex thoughts between eachother was one of the reasons of the human civilization.
This is why most stray dogs are from the zeroth generation, and you can use it against them (and this is why they aren't really dangerous, except if they are in a flock and have hunger).
Comment: Can't help but feel this is a terrible answer. As DJ above, dogs can get pretty high on a tree, and a lot of dogs can jump fences. (Only need a quick look on youtube to see tons of ordinary looking dogs jumping over fences that would most humans.) and the window thing is useless. This is "outdoors".
Comment: I feel the need to say that my dog can sprint up a tree 10 to 15 feet before gravity takes it down. You better be able to climb pretty fast.
Answer: Most things already have been said above.
What I can add is that if you find a tree, a dog can stay there for very long time.
A (domestic) dog we had once sat an entire day under a tree because of a cat.
I'm sure in a real situation you're not going to search for a 'comfortable' tree, but the most nearest tree, but it might be useful if possible to go to a tree where you can cut off a branch to use as weapon. So having a knife in your pockets is always a good idea.
Answer: A much less competent answer than the already provided. But at least succinct:

Stand up tall, raise trekking poles or hiking stick in the air to look big and dangerous.
Shout. ARGHHHHHHHH I WILL KILL YOU! In the most threatening way you can imagine. Don't stop.
Shine any trekking light you have access to within 5 seconds directly into their eyes.
If you had any other means you would have deployed them by now: gun, spray, stick, axe, friends, karate if you will. Now that you have made yourself appear threatening but the dogs are still approaching, pray. But never ever run.
Answer: Very good advice!
I have had good experience targeting the second in a pack - feral human or dog. Alpha is Alpha for a reason. If you kill or severely injure the second (which may be easier) packs react to this and will retreat. Remember an injured animal is soon a dead animal so they try to avoid this.
Your mileage will differ.

Should I run if I see wild dogs?


How to boot from ubuntu live usb with 'try ubuntu' directly?

Question: I created an Ubuntu 10.10 live usb with persistence feature. And it works well on my PCs. But one thing annoys me is that each time I boot from live usb, I have to choose between "Try Ubuntu" and "Install Ubuntu". Is there any way to dismiss that dialog and boot directly to the live Ubuntu system?
Comment: Why don't you install Ubuntu directly on usb
Comment: +1 from me. I'd love to hear a solution to this. My laptop's hard drive is dead, so I've been doing everything on a USB drive with persistence, and it would be wonderful to bypass this step at startup.
Comment: @Achu: a Live Session + casper-rw file/partition has its uses... read-only system files, no login screen (or password for sudo), untouched clean install files (no need to keep ISO for install in another PC), etc. I always keep one in all my pendrives
Answer: I wouldn't do it the way you have, but it kinda depends what you want to use the USB key for. If you want to use it to do installs on computers then the way you set up the key is right. If you want to use it as a standard desktop install, that you can use on any random (or even just a few specific) machines then use this method instead:-
For this you will need:

1xUSB key onto which you will install Ubuntu
2xCDR or DVD or USB key onto which you will put the installer
1xComputer which is capable of booting off the above device

Steps to install:

Download the ISO and burn it to a CD or DVD, or use USB startup disk creator (or unetbootin) to make an 'install USB key'
Insert the above media into a computer and boot from it
Choose 'Install Ubuntu' from the menu
Once booted to the installer, insert the USB key you want to install Ubuntu "persistent" onto
During the installer, when you get to partitioning, ensure you select the USB key inserted, to install Ubuntu onto.

Meaning, don't mistakenly install Ubuntu onto the internal hard disk on the computer

At the end of the install you need to tell the installer to put GRUB onto your USB key, and not to overwrite the bootloader on the hard disk (or indeed the USB stick you installed from - I have made that mistake!)
Once the install is done, you can shutdown, pull out all the keys and optical disks, and take that new key to any machine and boot from it.

Advantages to this method

It's a full desktop install that you can add packages to, remove packages from and generally fully customise as you would any install
You can enable encryption of the home directory during install so that if you lose the key you don't have to worry about losing your data

Disadvantages to this method

It's not as straightforward as making a persistent key, but it's no more difficult than a standard Ubuntu install
A full install on a usb flash key will cause more write cycles, and thus more wear and tear on the flash drive's memory, potentially causing it to fail much sooner
Comment: Yeah, I should have already tried that. Thanks :)
Comment: I found one problem with this solution. The USB disk cannot be formated in FAT format, which means it cannot be used in Windows system. Kinda inconvenient...
Comment: The main problem with this solution is that you cannot use it to install Ubuntu in another PC.
Comment: You cannot use it to install Ubuntu anymore, and it uses MUCH more space than usual persistent install - 3,5Gb instead of 700mb.
Comment: Sure you can, get a bigger USB stick :)
Answer: You can remove 'ubiquity' package, it should remove the switcher but removes the ability to install the system from that USB as well.
There's one more way: on boot of live USB there's a purple screen with keyboard = accessibility symbols in the bottom. If you press any key while it's shown, you'll get another boot menu, which allows to boot directly to the desktop, bypassing the switcher. It doesn't remove the switching completely, but at least works much faster.
Comment: I was looking around, and a possibly better solution is to only remove the `ubiquity-frontend-gtk` package, not `ubiquity`. That way, you can still install it by selecting it from the boot menu, but it can't start the installer window.
Comment: It does works a LOT faster. I use this myself... but its still annoying. I wish there was a way to bypass that and still use it as a Live Session (dont want a full install on USB)
Comment: There should be some way to make it automatically do this each time. Just need to figure out which config file is responsible for selecting the default option...
Comment: Using `sudo apt-get purge ubiquity*` does not remove the switcher and, also, it doesn't boot in "try" mode anymore.

How you remove ubiquity?
Answer: So far, I've been able to boot straight to my maverick netbook remix persistent live USB log in screen by edited the syslinux.cfg file on my USB drive.

Plug your live USB, go to syslinux folder on it.
Open txt.cfg (better use a code editor like notepad++), & copy the first five line.
The code looks like this on my maverick netbook remix :

default live
  label live
  menu label ^Run Netbook Remix from USB
  kernel /casper/vmlinuz
  append noprompt cdrom-detect/try-usb=true persistent file=/cdrom/preseed/ubuntu-netbook.seed boot=casper initrd=/casper/initrd.lz splash --

open syslinux.cfg, & change it's content with the code you've copied before. You can delete menu label ^Run Netbook Remix from USB or you can change it like this say Run Netbook Remix from this USB
(basically you can put any line as long as you use say in front of it)
save the changes you've made on syslinux.cfg, & we're done.

note : backup the original syslinux.cfg in case the method I explained above is not working for you.
Comment: I've used this several times. I would never have been able to work it out for myself. You are awesome :-)
Answer: I a Kubuntu 14 live usb bypass 'Try it' by changing the following in the syslinux folder:

Renamed syslinux.cfg to syslinuxOLD.cfg
Copied txt.cfg as syslinux.cfg
In the new syslinux.cfg 'append' line I removed the option ' maybe-ubiquity '

The first boot option now reads:
default live
label live
menu label ^Start Kubuntu
kernel /casper/vmlinuz.efi
append noprompt cdrom-detect/try-usb=true persistent file=/cdrom/preseed/kubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --

It now reboots directly to Kub 14
Answer: Another Simple Method to loose Try / Install
I usually use a USB with a Full install on it. It is no use for installing Ubuntu but a Full install is more secure, makes more efficient use of disk space and is more stable, among other things. Nowadays use "something else" when partitioning, or it is easy to overwrite the hard HDD. I also like to make the first partition either FAT32 or NTFS for use as a Linux / Windows Data partition.
Editing the Syslinux file, as previously mentioned is also a good way to get rid of Try / Install. For 18.04 use /casper/vmlinuz not /casper/vmlinuz.efi.
An easy way to remove the Try / Install stuff on a persistent drive, is to go to System Settings, and set yourself up as a new administrative user. The Try / Install will disappear, you will be able to assign a password, and the drive can still be used to install Ubuntu.


How does funding at UK universities work?

Question: The process for obtaining funding for graduate work in the UK seems much different than it is in the US. In particular, in the UK, funding decisions often come after offers of admission. What is the process by which a good, accepted graduate application at, say, Oxford, is given funding?
Comment: Can you clarify what you mean by "graduate work". Do you mean Phd positions or research associate (paid researchers)....
Comment: You need two things to do research - a place to work, and money to do that work.
In the US system there's a catch 22 here -- no one is going to give you money for research if you don't have anywhere to do it, but on the other hand, no one will give you a place to do research without money to fund it. So you have to get both, simultaneously, in some instances -- or the place comes with the money, or visa versa.

In England/Europe, this might be seen as a conflict of interest - 1 party is in charge of both the rent and the pay check. So it's broken down into two processes, as you describe.
Answer: The funding depends on your nationality/residence by a lot, as well as the field, the university, and the supervisor.
UK or EEA residents can get funding from national research councils (such as ESPRC, STFC and many more) which give them (usually) the cost of tuition plus a small living stipend (when I was applying the living wage was about £13,000).
Non UK/EEA people generally have to self-fund outside of a few special circumstances (competitive international scholarships such as Rhodes, university bursaries for internationals). This is very very rare. However, it's not terribly uncommon to see students from an above-average financial situation self-funding, but then they need to pay not only their living costs, but also the cost of tuition (at my old university it was about £20k per year for international students).
I wrote an extensive response on all of these issues here and here and here. The other answers from other users on those posts are also excellent.
So what happens is that you apply, and then you will be (hopefully) asked for an interview. If you are able to compete for the 'normal' funding pot, you will be interviewed much the same way as everyone else. First a shortlist, then the interviews, and maybe follow-up interviews will be used to select the best candidates from the pool of applicants. If you're non-UK/EEA, you may or may not interview with everyone else; it's up to the university. If they don't have the money to fund you, many departments will make you an offer anyway (especially for foreign students) which you will usually have several months to accept or decline.
The research councils will grant the department a certain number of PhD studentship bursaries, and they will distribute them. From what I've seen, you don't have to do much self-application for scholarships unless you're foreign. Though you will always be told where the money is coming from, and there may be some requirements (a yearly seminar, for example) to get the money.
If you are given a stipend, it is tax-free, unlike in many other countries. Your funding is all-inclusive, not split up into RA or TA like in the US. You can normally make extra money marking coursework or demonstrating in labs, although the 'estimated number of hours' taken by these activities doesn't always match up with the actual number of hours you spend on them !
Comment: *This is very very rare* While they are less common than UK/EEA places, in my field at least (life sciences), there are a number of institutions which have international PhD programmes. The MRC Laboratory of Molecular Laboratory, the Wellcome Trust, and the Francis Crick Institute are those that spring to mind for me. None of these are scholarships or bursaries, but are integrated PhD programmes, where funding and acceptance are tied together.
Comment: That's a good point @MJeffryes. I was thinking mostly about my previous perspective as somebody who had already been accepted to places but found myself thinking "so how will I fund this?". Since I wasn't at Oxford and ineligible for Wellcome/Fullbright, there weren't many options!
Comment: The ability to make extra money may be limited by university rules. E.g. at Cambridge a grad student is only allowed to do 6 hours of paid work per week.
Answer: As you say, an offer of a place is a different thing to an offer of funding. There are more places than there is funding, but not an infinite supply.
How each university/department handles this will vary. When I applied for maths at Oxford, everyone at the graduate open day was confused until we were told that they basically assume anyone who applies for funding won't come without it, so act accordingly until fairly late in the application cycle.
Funding also comes from different sources. Confirmation of funding will come at different points in the year. Some funding is specific to a particular project, so will be entirely linked to a specific place. Other funding may not be open to some students. Students can apply at different points in the year.
Basically researchers want the best students they can get, and they mostly expect to only get those by finding funding for them somehow. Unless you can fund yourself, an offer-with-funding is the only bit of interest to most people. The process of getting that depends on how obtaining the funding works, as some scholarships might need an offer of a place before you can apply.
Comment: It is not always about the "best". There are tons of politics involved. The best applicant may be in an area that the department is not interested in. There may be funded slots allocated to particular supervisors. Some research is more expensive...
Comment: @StrongBad Yes, if was a simplification, although by best I meant to include 'best fit'.
Answer: The process of allocating graduate studentships is a nightmare. Funding for graduate students comes from a number of sources including

External funding (from the research councils, charities, industry etc.) to named supervisors
External funding to the department
External funding to the university
Internal funding to named supervisors
Internal funding to the department
The department budget

Each one of these funding sources has constraints on who it can be given to. For example, external funding to an individual PI/CI is generally associated with a particular project. Conversely, the department budget can nominally be used for any student, but promises have often been made to individual faculty. When then department know the funding is available is often variable. For example funding from Doctoral Training Center grants to the university is often managed by a committee who look at students who are nominated by various departments.
There is also the issue of when the different sources of funding get confirmed. Grants come in at all times. The department budget is often not set until after decisions are made. Decisions about how to allocate funding from Doctoral Training Grants/Centres often require accepted and nominated students.
My department allocates funding in the following manner. We rank the students. Students of supervisors who have a dedicated source for them (external, internal, departmental) get told they have been accepted with funding. We then work our way down the rankings trying to find students most competitive for other sources of funding (e.g., DTG or University funding). Sometimes a very low ranked student might be the best candidate for a potential funding stream. We then more or less work our way down the rankings deciding if we want to guarantee funding for each student until we run out of guaranteed funding (e.g., departmental budget). As we start to run low on money (the last 1 or 2 students), we might shuffle the rankings to account for the cost of the student or the supervisor. Sometimes we will go over budget with the intention of either covering the shortfall from unknown sources or stealing from future budgets. Students are then told 5 things: unfunded, funding conditional on obtaining the particular nominated source, guaranteed but the student must apply for a particular source of funding, and funded.


Self-employed: claim CPP for self on Line 9060 of T2125?

Question: In Canada, self-employed individuals have to contribute more to the Canada Pension Plan (CPP): we have to pay both the employee and employer amount.  Whereas employees just pay their employee amount and their employer pays the other part.
Now, employers can deduct this payment on line 9060 of the Statement of Business or Professional Activities (T2125).
Can't the self-employed business owner claim their own Employer part of the CPP here, which will take that amount right off their taxable income? Which wording excludes this?
It says not to include "salaries or drawings of the owner(s) of the business since salaries or drawings paid or payable to you or your partners are not deductible", but is the CPP such drawing? It's not payable to to the self-employed individual, but to the revenue agency. Or does the government count among "your partners"?
Answer: This must be ruled out by the fact that the personal tax return already provides, for self-employed, exactly the same thing: a tax credit for half of the CPP. For 2018 this is Line 222 ("Deduction for CPP or QPP contributions on self-employment and other earnings"), which comes off the Net Income as part of determining Taxable Income.


Getting a BSOD when installing windows xp

Question: I have installed Windows 7 on my laptop. Now I want to install Windows XP. How will I be able to pull this off without using Windows XP mode or any virtualization solution so that I could dual boot 7 and XP?I always get a BSOD when trying to boot up the XP installation CD.
I got this on Nirsoft's BSOD viewer:
Answer: Could it be your harddrive is set as SATA drive? You need to set it to Compatibility mode to boot with XP, or slipstream a SATA driver to a new XP CD


How to use block and transaction hashes for generating simple stochastic chances?

Question: Many online Bitcoin gambling websites use the block chain info to prove fairness. Most of them use rather complex algorithms for this with pre-published secrets.
What most of them basically achieve: Convert a block hash or a transaction hash to a number in a certain range.
What is the simplest way to do this in a fair way, verifiable by everyone? I would like to focus mostly on using block hashes, which are the least manipulable.
With a simple way I'm looking for either a very simple mathematic way to do so or either a library which can do it for you.
I understand that predefined secrets are required when transaction information is used, because these are easy for users to manipulate. Block information, on the other hand, is far less easy manipulable. If you want to generate a block with a hash that would make you win in the game, you would make the standard block generation problem even more difficult and you will have to do solo mining  which is already quite hard when doing regular mining.
So, are these secrets also required when using block information?
Note that I am an engineering student myself so I will probably understand much cryptographic and mathematical terms, but the purpose of this question is of course to receive an answer that everyone can understand.
Answer: Here's the way SatoshiDICE does it:
SatoshiDICE has "secret keys" for each day which they pre generated for the next 10 years. They published the hashes of those keys so you can verify they didn't change them. When a transaction comes in, they hash the transaction hash and the secret key for that day, then take the first two bytes of that. Then, a few days later, they publish the secret keys.