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Comment Re:What creates the temperature differential? (Score 5, Informative) 170

Does she put it in the fridge before using it or something? Or does it use the difference in temperature between your hand and the flashlight.

The latter.

If you RTFA you'll see she's using the aluminum flashlight body as a heat conductor and the "head" and other exposed portions of it as an air-cooled heatsink.

She's stuck the handle of the light into an insulating plastic pipe, cut a hole in the pipe, and stuck the peltier cell in the hole, with the "cold" side in contact with the flashlight handle and the "warm" side in contact with the hand. (I expect the next step is to wrap an outer aluminum tube around it to conduct heat from the whole hand to the cell, rather than just heating it with a patch of palm directly contacting it.)

Voltage boost converter between the peltier assembly and the LED (because the peltier cell she used was not stcked for the right voltage to drive the LED.) The LED shines as long as you hold it, if the air is cool enough. (She's used it for 20 minutes running.)

Also, since this is generating electricity from a temperature differential, rather than generating a temperature differential from electricity, wouldn't this be the Seebeck effect?

Yes. Seebeck discovered current generation from heat differential (with dissimilar metal wires and a compass needle), then Peltier discovered heat-pumping with current.

But, like most rotating electric machinery (where the same device is a motor or generator depending on whether you power it or twist it), the same effect is a heat pump or heat engine (depengding on whether you apply a temperature difference and pull power or apply power and pump heat).

The effect is now often called the "Peltier-Seebeck effect" in textbooks. The cells are typically called Peltier Cells because the efficient ones are manufactured mainly for heat-pumping, though they work just fine both ways.

Comment Noise canceling is NOT the key. (Score 1) 120

The noise-cancelling scheme sounds interesting.

If you'll read TFA a little more closely than the OP did, you'll find that the noise-canceling thing is NOT how they got the 1G-ish single-pair link to work.

What the noise-canceling thing is about is when you have TWO OR MORE pairs bundled into a single logical link. Then it figures out what the cross-talk between the individual pairs looks like and cancels THAT out. This lets the individual signal pairs run as fast as a lone pair and the total bandwidth of N bundled pair be N times the bandwidth of one, rather than substantially less.

Comment QED (Score 1) 287

But open source prevents this from happening because the source is constantly being looked at!

No, open source doesn't keep it from happening. Providers can stick any cruft in there that they want.

What it does do is make it much more likely to be discovered when some fool DOES stick it in there. Don't be surprised if you hear about a lot more bad stuff found in open source than you do in closed source, as a result. (At least until the bad guys wise up.) Try to find the malware in Microsoft's stuff, for instance. B-)

(Of course this stuff was found with a packet sniffer before anybody found it in the code. So it's an apples-to-oranges comparison and open/closed source has nothing to do with it.)

Comment Re:Some contest (Score 1) 194

Because this way, it's democratic. That's how democracy works: the upper class lets you vote for what you want before doing what they want.

FTFA (emphasis by me):

And in place of Vulcan, they submitted third-place Styx (87,858 votes), which in addition to being a river, is also the name of the goddess of unbreakable oaths.

Comment Re:This looks like gross error (Score 1) 145

Yes, I looked at the video. And it shows nothing of the sort - as the rocket goes past horizontal, all engines can briefly be seen to be firing normally with no signs of fire. (At least in the other videos I've seen, it's not clear in the video linked above.)

The OP is correct, the indications (that we can divine from the video) point to a control failure either in the guidance system and associated electronics or the mechanics of the gimbals. One key clue is the unusually high roll rate that builds up quite early.

Comment Re:why test microsoft windows for free? (Score 1) 543

Yes, the average 18 to 45 consumer spends a lot more time on their phone than they do on their computer.

Then they go to work, and they're faced with doing their job, with a PC that's organised completely differently.

There's been a rather huge corporate investment in getting desktop machines sorted to maximise productivity, with applications developed, training provided, and documentation written. I'm talking about billions of dollars in investment, and so much of which would have to be re-spent to use the Windows 8 UI.

Take-up among the Corporate sector? Don't hold your breath.

Comment Re:Funny. (Score 1) 543

It just sounds like a bunch of Whiny people who wants to get an Apple or Defend Linux, or are so old or autistic that they cannot handle any change.

And your comment sounds rude and rather incredibly arrogant.

I believe the criticisms with the UI I've read above are relevant and germane. And, supporting several thousand users over the phone, I am not enjoying the workload increase from having to explain the chaos of W8 to the clerical staff who are trained to a pattern in XP or W7.

The best thing Microsoft did after introducing W8 was to fire Sinofsky.

Comment I'm in Silicon Valley (Score 1) 395

I'm in Silicon Valley. I want to live in Nevada, far enough from the neighbors that I can't hear their HIFIs in the daytime or see their lights at night.

I want to live in Nevada so much that I built a house there - a few miles over the state line near Lake Topaz. Fully paid for. Marvelous view. Good neighbors. Also rabbits (jack and cottontail), quail, coyotes, deer, antelope, bobcats, cougars, and black bears. Gun laws are a lot different there, and I have a Nevada CCW that's also valid in many other states due to reciprocity (though not in CA).

For the Town House near work I also moved across the bay from Palo Alto. Just off the other end of the bridge, for less than I was paying in rent in Palo, I was able to BUY a two-story four-bedroom with 7,000+square feet of yard and remodel it. 200A electric service (two 20A circuits to each room for starters). Satellite TV and Cat 5E everywhere. (Only running 100M at the moment but I hear that with house-sized runs you can get away with 5e for gigabit Ethernet.) The yard is now a garden and orchard. We get most of our veggies from it - and our eggs. We were also on the Bay Friendly Garden Tour last year.

They tell me the city here on the Back Bay has a gang problem. But for several blocks around our house it doesn't. It's much like in Palo Alto (where the burglars worked their way down Loma Verde street and skipped only two houses - ours and the retired cop two doors down). It seems the crooks don't like to bother NRA instructors, and the wife's "Ducks Unlimited" sticker tells them she can hit a spot the size of a duck (or a human heart) with a shotgun, from 50 yards, even if it is flying at the time. B-)

Of course NV has no such crime issues. Even machine guns are legal there. B-)

Move to a SF or Oakland? By preference? You've GOT to be kidding.

Comment Re:Fixed the summary (Score 1) 158

Not all measurement results can be well-defined deterministic properties of the system. If all of them are determined, they cannot be just system properties, but must depend on the way they are measured (i.e. they are contextual), and if all of them are pure system properties (i.e. non-contextual), they cannot be determined.

I'm not sure whether the problem also occurs with position and momentum, but I'd not be surprised if it does.

See Wikipedia for details.

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