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Comment: Re:Great to see (Score 2) 152

by Michael Woodhams (#48800243) Attached to: Chinese Spacecraft Enters Orbit Around the Moon

A minor nit-pick: I think you mean "chemical rocket".

Probably the most common rockets are liquid hydrogen/liquid oxygen. Neither are fossil fuels. Solid rockets could contain oil-derived plastics in their fuel, I don't know enough to say how often this is so. SpaceX uses kerosene/liquid oxygen which does use fossil fuel, although I expect it wouldn't be hard to substitute a suitable biofuel if they really wanted to.

Comment: Re:Great to see (Score 5, Interesting) 152

by Michael Woodhams (#48799757) Attached to: Chinese Spacecraft Enters Orbit Around the Moon

Since 1969 there have been people living on Earth who have visited another world. It would be a terrible failure of humanity if one day this was no longer true. I am not fond of the Chinese government, but if they send people to the moon, I'll be enthusiastically cheering them on.

Comment: Re:Rock paper scissors (Score 1) 340

If game theory mathematicians say they've got a strategy which provably can't be beaten, I'll believe them until someone finds a flaw in their method. Mathematicians are notoriously picky about what constitutes a 'proof'. I'm sure they are quite aware of the possibility of an opponent which knows their strategy and adapts to it. (Note that in the rock paper scissors example, knowing the perfect strategy does not let you beat it.)

The article does not specify whether the strategy is deterministic or probabilistic. I expect the latter: sometimes its big lookup table will say "in this situation, raise 15% of the time, fold 85% of the time."

Comment: Rock paper scissors (Score 4, Insightful) 340

by Michael Woodhams (#48771147) Attached to: Researchers "Solve" Texas Hold'Em, Create Perfect Robotic Player

You can better understand what is going on by considering the much simpler game Rock paper scissors. 'Perfect' here basically means the strategy gives you the best possible worst case.

For RPS, the perfect strategy (using the term in the same sense as it is used for the poker bot) is to play completely randomly. There is no way to gain an edge over this strategy, no counter-strategy which will give you more than 50% chance of winning, even if you know your opponent's strategy. (In this case, there is also no strategy which will give you less than 50% chance of winning against the 'perfect' strategy.)

For the poker bot, there is no strategy that will give you greater than 50% chance of winning against it in a two player game. If you know its strategy perfectly (but of course you don't know its cards) the best you can do is to equal that 50% chance (which is what happens if it plays itself.) Unlike RPS, you can can lose to the perfect poker bot by playing poorly. Also, as noted in the article, the perfect poker bot always plays as if it were playing against perfect opposition. A good human player will fleece you faster then the perfect bot, because the human player will notice your peculiar imperfections and exploit them, choosing to play in a way which would be suboptimal against a perfect opponent, but superior against you.

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Comment: (Score 1) 720

by Michael Woodhams (#48487263) Attached to: Ask Slashdot: Making a 'Wife Friendly' Gaming PC? is a web site dedicated to quiet and silent computing, with extensive reviews and forums. They have very recently posted a sample build of a quiet gaming PC.

You can take that as a base and adjust according to taste. (For example, I'm more obsessed by quiet and less by frames per second, so my gaming PC has a single GTX760Ti GPU.) If you have questions, take them to the forums.

Comment: Re:Some details from the paper (Score 1) 145

by Michael Woodhams (#48480853) Attached to: Scientists Develop "Paint" To Help Cool the Planet

Emissivity and absorptivity are the same thing. One way to look at this is the time-reversibility of physics on a microscopic scale, another is that something that was really absorptive but not emissive or vice-versa would give you a really easy way to beat the 2nd law of thermodynamics. Emissivity can, however, vary with wavelength, which is the trick here.

Comment: Re:Some details from the paper (Score 2) 145

by Michael Woodhams (#48476975) Attached to: Scientists Develop "Paint" To Help Cool the Planet

Not really - the 40Wm^2 of cooling is only useful if it is in contact with something that can move that cold to where it is needed. (Hand-wavy explanation, really we are shifting heat to the film.) It also needs to see mostly sky, which windows usually don't.
You'd put it on your roof and run water behind it to shift the heat around.

The superior man understands what is right; the inferior man understands what will sell. -- Confucius