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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:Call me crazy... (Score 1) 89

Funny, I was about to post that my Samsung Galaxy S7 already has a 3000 mAh battery, and it is rarely enough to go a day and a half without charging. 4500 mAh might give me 2 days. Just in case, I keep a fully charged solar panel 20,000 mAh battery in the car, which should keep me going about a month in normal Oregon weather, and would keep me going indefinitely in a desert.

Comment Re: The US ranks with Mexico? (Score 0, Insightful) 107

Nah, it's because the rich don't want to pay Americans what they're worth. They'd rather import illegals to work for $5/hour cash and ignore the labor laws, safety laws, overtime laws, etc. It's pure selfishness as well as disgust at the vile deplorable American people. It ain't ordinary folks who benefit from illegals.

Comment Re: s/drug trials/climate change/g (Score 1) 320

The same experiment has been done for 100 years, and consistently reproduces the same results. Take a sealed, transparent tank of air. Shine sunlight on it. Take the temperature. Increase the percentage of CO2 in the tank. Shine sunlight. Take the temperature. The CO2-richer air has a higher temperature.

Comment Re: The real question is (Score 1) 86

Same here. Our 2100TN is still running like new. I don't know that I'd be able to find a newer model as reliable.

I've had pretty good luck the past 10 or so years with a LaserJet 1320. Quick, built-in duplexer, built-in PostScript, works with everything. A couple years ago, I was given a JetDirect 175x, so it's now on the LAN. (Had some other network-to-USB adapters before the JetDirect that didn't always work as expected.)

Comment Re:How far they have fallen (Score 1) 86

The brand logos have been removed.

In one shot, it looks like they didn't obscure the Apple logo on the printer (upper right corner of the front), though it's so small that you wouldn't have been able to tell that's what it was.

I still have mine from coming up on 32 years ago. It's currently in storage...not sure if it still works, though it did the last time I had it out. It'd almost certainly need a new ribbon, and I think the last of the fanfold paper got chucked a while back. I still have some Apple IIs (and also some Macs now) that can drive it, too. :)

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