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Comment Re:Heat (Score 1) 176

I would be more interested in this if it worked the other way, warming my house.

There are lots of designs for doing that. Look at any renewable energy bulletin board (such as fieldlines.com).

Common thread is:
  - Black (or otherwise visible light absorbing) target.
  - In an insulated box.
  - With a glass window (that does NOT have an infrared reflective coating)
  - And some way of transferring the heat from the black target to the house air.

Glass is opaque to infrared and passes visible light. Sunlight goes through, is absorbed by the black material, and heats it (to the tune of about a kilowatt per square meter at noon). The material re-radiates, but it is far too cool to re-radiate in the visible spectrum. So it re-radiates in the infrared, which doesn't escape through the glass and is thus re-absorbed.

It's called "The Greenhouse Effect". B-)

In one of my favorite designs the black target is a series of tubes consisting of used aluminum drink cans with the tops and bottoms removed, painted black. They're very good at absorbing light, because it takes multiple bounces down the valley between the tubes, giving the paint many chances to absorb it. A 4" computer fan pumps air through the box to extract the heat.

But there are LOTS of other designs. Including houses with large south or south-east facing windows and overhanging roofs that shade them in the summer but not in the winter (to rough-tune the absorption). The floor, walls, furniture, etc. serve as the visible light absorber.

My ranch house works like that - a little too well. In the afternoon it will git to 90+ degrees when it's single-digit temperatures outside.

Comment Re:Too good to be true. (Score 1) 176

It's a neat idea, but what happens in the winter?

Put a cover over it.

Glass is good. It is pretty much opaque to far infrared. Instead of seeing the cosmic background temperature of a few degrees kelvin, it will see the temperature of the glass - which is about the same as its own temperature. So the radiative heat flow will be just about zero.

But ANYTHING opaque to infrared will do the same.

Another approach: Instead of coating the house, coat a radiative cooler to make chill water, and pump that through a heat exchanger in your forced air heating/air conditioning system. Don't want cooling? Don't pump the water. (Adjust how much you pump it to regulate your temperature.)

That's not "no power", but pumping chill water is very little power, and you need to circulate the air anyhow. Most of the energy cost of air conditioning is refrigeration, and you still get that for free.

Comment RTFA. They DID try it on people. (Score 1) 151

RTFA. Then follow the link to the paper. They DID try it on humans. Worked reasonably well (though the sample was small so it was more "does this maybe work on people, too? Is it worth a big study to check?" rather than "do all the results reproduce in people just like mice or are they quantitatively different in THIS way?").

Interestingly, they used a proprietary commercial boxed Fasting Mimicing Diet - L-Nutra's ProLon (Developed by a team including a USC Davis professor specializing in gerontology and life-extension) - on the human experimental subjects.

Comment Re:One hour of basketball dunking per day. (Score 1) 141

Our schools (generally speaking currently mandate 3-4 *years* of PE and 0 years of computer science.

Some students are terrible at PE. So what? We make them do it anyway. These might even be the same students that excel at computer science, if the stereotypes are true.

But this isn't even a mandated year of CS. It's a bloody single hour, lodged somewhere in between the 4th and 12th grades. If you think we can't spare a single hour for coding, I don't know what to tell you.

The biggest obstacle to CS education is the sheer fact that nobody is exposed to it at an early age, so they don't know if they like it or are good at it before going to college. This stands in contrast to basically every other major STEM field, where everyone has an opportunity to (or be mandated to) take a high school level class. But only about 1 in 10 high schools even offer CS these days, and the numbers are going down because they're usually not counted for college science requirements.

So, no, this bill really is a good thing. The Hour of Code is so simple even troglodyte teachers can run it for their kids.

Comment Re:Do we need more evidence... (Score 1) 180

You just accept them because you are affiliated with the same party.

THAT'S A GODDAMNED LIE.

See, that's exactly the short of fucked-up false-dichotomy thinking I was complaining about in the first place! I'm a LIBERTARIAN , not a Democrat.

The Clintons, both of them, are every bit as horrible as Trump.

That's the thing, THEY'RE REALLY NOT. The Clinton's are horrible in a "normal" corrupt-big-government sort of way, but they PALE IN COMPARSION to the damage to civil liberties and democracy itself that Trump is doing! The Clintons never (a) kicked the media out of white house briefings, (b) stuffed their administration full of LITERAL WHITE SUPREMACISTS, attempted to normalize lying to the public in a strategy straight out of 1984 or Mein Kampf, or done any of a hundred other ACTUALLY, LITERALLY, AND WITHOUT EXAGGERATION FASCIST things!

Comment Re:Costing to the RIAA vrs Ignoring? (Score 1) 81

You grossly overestimate the cost per notice. To the rights holder the cost is basically zero.

Well, the copyright holder first has to determine whether the content is actually infr-- (snicker, choke, guffaw)

Sorry, I just couldn't get that whole sentence out while keeping a straight face.

Comment Re: Great idea... But there is a problem... (Score 1) 303

visibility is a couple kilometers

First, thanks for your very interesting posts. Do you mean visibility at ground level or at the altitude where the pressure is 1atm ? If the former, then why did the Russian probes only show pictures with about one meter of visibility ?
Personally I really liked the idea put forward at the end of K.S.R.'s Blue Mars: put a gigantic thin (monomolecular) film at L1 between Venus and the sun to lower the solar input and let Venus atmosphere condense to the ground.

Comment Re:Holy communion in space (Score 2) 154

Yeah, I don't really understand this rule. It's not like you pee alcohol after drinking it, it's transformed by the body (acetaldehyde, then acetyl).

Also I tested a water recycler for a year while in Antarctica, which was intended for space use (it was an ESA model, probably different from the NASA one), and there was no limit to the amount of alcohol we could drink (fortunately!!!), yet the only issue was with some shampoo and urine: we had to use the officially sanctioned shampoo and we were forbidden to pee in the shower ! Well, now that I think of it, it could have been due to the high alcohol content ! No, seriously, IIRC it was the urea which would damage the reverse osmosis filters.

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