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The video at the end of the article is absolutely fascinating.

Also, it's the first time I hear that rejecting heat is a big deal in space. If anything, I would have assumed that heating the station would have been a problem, rather than keeping it cold.

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Most people assume that, and most sci-fi reinforces that opinion. But a generic Thermos is a vacuum flask.

Space is an incredible insulator. The only way to cool things is to radiate heat.

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The sci-fi game series Mass Effect had a good explaination for this, and tied it in with the notion of ships having recognizable "signatures":

http://masseffect.wikia.com/wiki/Codex/Ships_and_Vehicles#St...

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It also works similarly in Eve Online, btw.

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Indeed, whenever corp-mates would ask why there are brightly lit "windows" on their ships I would point out that they were actually heat dissipation panels.

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A major mechanic in Elite Dangerous is managing your ship's internal heat and heat signature.

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Thank you. TIL, actually not learned realized, space is actually a good insulator out of earth conditions too. Prejudices. We can never know what if something we thing is a reality or prejudice. Science and skepticism is that important.

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Also of note is that while a vacuum doesn't necessarily have a temperature (it's just a medium), space does.

Even if you go far away from anything else, you will still reach thermal equilibrium at the Cosmic microwave background (CMB) temperature, which is 2.7K -- it's essentially the "temperature of the universe", radiation which has been emitted as far back as the first moments of the universe.

And of course, if you create a vacuum chamber on Earth, any object inside will always reach equilibrium at ambient temperature (in the lack of any heat engines on the body -- even then the fuel would deplete some time).

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Technically interplanetary space is a hot plasma too. The particles emitted by the Sun are very hot according to kinetic theory (which only depends on the mean velocity of particles) since they have a lot of energy. It's a plasma because the particles are charged and accelerated by the Sun's magnetic field.

Of course the density of these particles is very low, so if your definition of heat factors those in then space is cold.

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Why did it get so cold inside of Apollo 13 then?

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My understanding is that the spacecraft was designed to radiate large amounts of heat, with the expectation that systems inside the spacecraft would be producing a lot of it. Apollo 13 shut down much of the equipment inside the spacecraft, which meant that it was no longer producing as much heat as was expected.

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Evaporative cooling ought to work really well?

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It would with an unlimited supply of coolant, but bringing mass is expensive. Unless you start grabbing asteroids and using your waste heat to vaporize them or something....

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Bolt habitat to asteroid heatsink, profit.

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That's what we have Planetary Resources for ;).

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But that would use up material, all of which has to be trucked up to orbit at great expense.

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you can have further insight here http://www.projectrho.com/public_html/rocket/misconceptions.... and then lose countless hours on that website if the topic fascinates you

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And then go and play Kerbal Space Program to get these concepts become intuitive. Warning: another countless hours sink.

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your not wrong with losing hours...

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so my stupid question is, cannot it be used for power? Surely the same system which radiates the heat can be exploited to generate power with something akin to a sterling engine.

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A heat engine is great when your cold sink is 'free', but here, the cold sink would be the radiator fins, and extracting energy from the temperature difference between main ISS and radiator fins would effectively just make the radiator fins worse at cooling the ISS.

Which is fine if you have lots of excess radiator fins. But they almost certainly don't -- shipping up extra radiator fins in order to get power from the excess cooling capacity would be less efficient than just adding solar cells (efficiency of a heat engine maxes out at 1 - (T_cold / T_hot)).

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These radiators exist specifically to deal with power which has already been used. As stated in the article, the station needs a few kW of electrical power. Eventually all this power ends up as a waste heat energy. There is nothing that can be done with it, so it has to be dumped into space.

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There's also solar heating of the station itself to worry about. Although to some extent you can make the station reflective (white) to deal with that.

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The barbecue roll. The Apollo spacecraft would slowly rotate along it's longitudinal axis while it traveled to the moon to help dissipate heat.

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Hmm. That made me wonder about Apollo 13, where the "crew endured temperatures at or below freezing for the bulk of the return flight" [1], apparently [2] because they had to turn off heaters and electronic gear to conserve power.

The fact they had heaters suggests that the roll wasn't so much to dump heat as to spread it around, to reduce the risk of structural damage from differential heating [3]. That's presumably less viable on a big structure like the ISS.

[1] http://www.spaceline.org/flightchron/apollo13.html

[2] https://answers.yahoo.com/question/index?qid=20121015080310A...

[3] https://books.google.com/books?id=31GqndM3fk8C&pg=PA419&dq=d...

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Space is pretty much a perfect storm. As if relying only on radiating heat were not enough, you need gravity (or some acceleration) for convection to work. And then simply pumping a fluid through tubes is an interesting issue when the fluid does not know which way is down.

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> it's the first time I hear that rejecting heat is a big deal in space

Play some Mass Effect :)

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Same exposure to the sun, but no air convection.

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And if Argentina is like Brazil, never ever hold the straw with your hand. Only your lips should touch it.

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Simply touching it is no big deal (in Argentina at least), but god forbid you stir the yerba, then you're in deep trouble.

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Brazil's "chimarrão" (as they call the mate) is prepared pretty differently than we do in Argentina, and the customs are a bit different. They use way more yerba, a much bigger gourd and it's not as social (at least in Santa Catarina I very rarely saw people sharing the gourd.)

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There's also "tereré", which is like "chimarrão", but it is infused and consumed with cold water instead of hot.

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well that's because it makes all the powdery crap sink to the bottom instead of the big chunks acting like a filter

Paraguayans (at least the Mennonite colonists) don't have a problem with touching the bombillia either

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>(no need for WinZip or WinRAR - think about it!)

I'd be surprised if compressor utilities running through Cygwin's emulation layer could achieve the same speed as a native tool. 7-zip is an open source tool that will handle all your compression / decompression needs on Windows (including rar, gz, many self-extracting exes, and a bunch of very exotic formats). You should really give it a try if you're compressing or decompressing large archives on Windows.

http://www.7-zip.org/

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Cygwin should only slow down syscalls. Syscalls should not be a significant fraction of the running time of compression software.

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> I'd be surprised if compressor utilities running through Cygwin's emulation layer could achieve the same speed as a native tool.

Why do you think so? The emulation layer should only be relevant for the IO part of the compressors and IO is usually severely limited by the harddisk anyway.

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If you're in Paris, you can see some of his sculptures being showcased (with live performances every half hour where a demonstrator shows how they work) at la Cité des Sciences until January 4: http://www.cite-sciences.fr/fr/au-programme/expos-temporaire...

Saw it in April, and the whole exhibition was pretty cool. It's about art and robots. My favorite thing was the 3D water matrix by Christian Partos and Shiro Takatani: https://www.youtube.com/watch?v=TPvBV7VMqiY - I spent maybe an hour watching it.

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China officials would probably deny that it was them if the US publicly accused them, saying it was some isolated hacker acting on its own, or maybe a foreign country routing its traffic through a VPN in China, AND they would point out that the US is doing exactly the same in China and elsewhere (Stuxnet, etc...).

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Don't know about the rest of Africa, but in Cape Verde I was paying 15 euros for 5 gigabytes of 3G bandwidth. I was buying two of those cards per month on average, which was on par with an internet bill in the US or in Europe.

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Except, corrected for average purchasing power in Cape Verde, that's about 10 times more expensive.

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On par with an internet bill that provides far more than 10GB of data. I get 300GB for that price for example, and anything I transfer at night doesn't count towards that cap.

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But you're getting that bandwidth in Africa, so honestly that's not bad. Not really a fair and equal comparison...

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But the claim was the Africa doesn't need better internet because they have 2g/3g. Go ask anyone in Africa if they wish they had more bandwidth, more data, and lower prices.

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And it gets especially annoying when those slides are rendered as a static PDF file. Lots of information gets repeated. It was especially ironic in the slides about Frames, Dictionaries and K-SVD, as they were talking about doing efficient and sparse representation of things.

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I actually prefer slides in PDF form rather than .ppt/.pptx, as long as all the immediate transitions are omitted in the .pdf file. OpenOffice and LibreOffice have trouble rendering some .pptx files, and it's just less convenient than firing up a PDF reader

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> Give mintty a shot: you'll never go back to conhost.

No, give cmder a shot: http://bliker.github.io/cmder/ I've tried mintty and cmder, and cmder was just perfect for me.

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I use Mintty because Cygwin's tmux didn't work with ConEmu or Cmder, but Mintty was ok.

FWIW, I took a quick stab at the tmux & ncurses code to try to find a fix, but it was far from obvious. Maximus (ConEmu author) said it had to do with how cygwin flags stdin streams, which just happens to break when ConEmu provides them. (sorry details vague)

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Quickly scanning the code, it looks like ConEmu is using hooking to implement the Win32 console API and forward calls to the terminal emulator. That's a good approach, but it needs to be integrated into the Cygwin pty system to really work well in that environment.

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How does cmder compare to ConEmu?

https://code.google.com/p/conemu-maximus5/

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It appears to be built on ConEmu. From the homepage:

> Think about cmder more as a software package than a separate app. All the magic is happening through Conemu. With enhancements from Clink.

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Oh my goodness thank-you! I'm forced to use Windows at work, and this is the first terminal emulator that looks not terrible!

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Might take a look at Babun[1] as well. It's a fairly pretty emulator with a built-in cygwin tree, and integrated (default) zsh.

[1] https://github.com/babun/babun

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The problem I have with console replacements is most of them break readline. You can't run many interactive programs with them. On the other hand, you can't have full unicode support without a console replacement.

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Indeed. People need to stop thinking in terms of building win32 "terminal emulators" (most of which involve god-awful hacks, like scraping hidden conhost windows) and instead emulate the Win32 console API in userspace (just like Windows itself did before Windows 7) and implement the Cygwin pty interface in terms of this library. This way, Cygwin programs think they have a pty and Win32 programs think they have a console, and everything Just Works.

But people would rather just hack up a "terminal emulator" instead of doing things the properly and the hard way.

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I bought an Asus Zenbook UX303LN 2 weeks ago after my 13" MacBook Pro got stolen, and while there are things that I miss from the MacBook (essentially, the fantastic touchpad quality), I'm overall satisfied with my Zenbook. It's a solid alternative to the MBP at a very attractive price. The only real issue is the touchpad. While it's not bad, there are a lot of things that just don't work as nicely as on the Mac. For example, if you try to rest your thumb on the touchpad the cursor will stop moving. Little things like that.

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I don't understand why, after all these years, literally no other manufacturer has been able to nail the trackpad like Apple. The first few "clickpads" I used on laptops trying to imitate Apple were basically unusable, but even on recent models I've played with in stores, they're always just....not quite right to horrible.

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I believe the trackpad of my asus 1000he notebook is pinnacle of non-mac trackpads.

Supported equally on linux and windows. Soft to the fingers, responsive and precise. Two-fingers scrolling, wipe (kind), three-fingers scrolling, etc.

Only missing thing is pinch-to-zoom.

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The trackpad on my Samsung np770z5e is great. Just install a good SSD on it and you have a great laptop (battery life is also very good).

Edit: it also supports three fingers prev/next commands

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This is my go-to place when I need inspiration and motivation: http://www.thisiscolossal.com/

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