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Comment Re:Of-course it is a checkbox (Score 2, Informative) 75

But many types of video processing DO scale very nicely, as racks and racks of SGI machines proved years ago ("rendering farm" is a beautiful name for computers...). The "flow of time" argument against scaling, which is basically an argument against easy parallelization, works for some things but not others.

Even when the analysis or manipulation of one frame depends heavily on those before it, most video (or audio) work is broken nicely into scenes (or tracks/movements) which can be easily scaled - damn near linearly.

Financial markets work similarly. Yes, there is a very important interdependence, sequentially significant, but only between certain transactions. There may need to be "traffic cops" that don't scale linearly, but other parts of the transactions will scale nicely.

In the limit, nothing that we do will scale efficiently forever (to extremely large OR small), but video processing and financial systems are two examples which seem to scale quite well.


NASA Tests Flying Airbag 118

coondoggie writes "NASA is looking to reduce the deadly impact of helicopter crashes on their pilots and passengers with what the agency calls a high-tech honeycomb airbag known as a deployable energy absorber. So in order to test out its technology NASA dropped a small helicopter from a height of 35 feet to see whether its deployable energy absorber, made up of an expandable honeycomb cushion, could handle the stress. The test crash hit the ground at about 54MPH at a 33 degree angle, what NASA called a relatively severe helicopter crash."

Comment Re:Replace compressed air with compressed hydrogen (Score 1) 278

Any car with hydrogen power is going to have highly compressed hydrogen gas onboard. There are efforts at storing it other ways, but to my knowledge nobody uses them in cars at the moment, as they would be frickin huge. Whether the hydrogen is ultimately burned in a fuel cell or an ICE (using some of the compression energy as well) shouldn't make much of a difference to the safety of the fuel storage. Just like with a gasoline car, most of the danger is in the tank, not what kind of engine is up front.

Comment Re:Seen from space (Score 1) 177

I sure hope not. Can you imagine what the electric bill would be if the insulation was that poor? And of course just a short distance away would have to be a HUGE heat output from condensers or heat pipes taking all that heat away. My guess is that a high-res thermal imaging satellite could see the heat from the HVAC above, but never the cold areas below around the accelerator itself.

Comment Re:Seems silly (Score 1) 220

Of COURSE!!! And penguins, who wear tuxedos comprised of millions of Maxwell's demons that, like your imagined polar bears, actually take heat from their surroundings while maintaining a much higher temperature...

Oh, and there are trolls that do similar things, but can do so over amazingly long distances using advanced technologies. They are, though, a type of parasite, depending on other relatively un-advanced creatures to feed them negative entropy.

Comment Re:Actually, the shuttles have taught us a lot (Score 1) 297

There was a paper a few years ago by a guy at or previously at NASA (I'm being lazy tonight and not looking it up, but I'd be happy to find it if you like) which rather convincingly showed that if we used a shuttle on the schedule ORIGINALLY planned for it (several launches per month rather than per year) it would have been cost effective.

I'm not sure if your statement that we're much closer to reliability and "cheapness" is meant to imply that the shuttle has helped in this respect, or not; we could argue whether it has helped give only motivation if not otherwise contributed directly to practical experience in reliable and inexpensive launches. In either case, it has been a very expensive (per launch) platform because it didn't work out as planned, and we have hopefully (!!) learned something about how the government needs to plan for things...

That said, my impression is that there is no such possible thing as a cheap, reliable, NON-commercial launch. Whether we achieve such a thing commercially is up to SpaceX and SpaceX alone, in the short term.

Comment Re:Problem with wind and solar? (Score 1) 412

I'd bet money that we've moved more stuff down than up - here are things that could go either way that have way more impact than buildings:

- Roadway cuts/causeway building
- Dams and reservoirs
- Coal and other mining, both deep and mountain clearing
- ???

On average I would have to guess these things almost balance out, but my money's with gravity on this one.

Comment The soap box (Score 2, Insightful) 138

While your three boxes are neat and tidy, there is one box you've left out that everyone in a representative democracy is supposedly guaranteed above all others - the soap box.

This one is most important here, since the jury hasn't yet been formed, there is nothing in the legislative pipeline that will likely reform copyright if some person or persons is elected, and of course killing people or threatening to do so is way out of line in this case.

Basically what is happening seems to be a conflict between:

  1) somebody's right to limit others' free speech involved in suing (in front of a jury eventually?) to protect their claimed legal copyright to limit others' free speech, and

  2)free speech itself.

Comment Re:Opportunity (Score 1) 609

assuming North Korea didn't include an auto-destroy mechanism onboard

If they did, they better hope it worked better the the rest of the mission.
Turns out, it IS rocket science! Who'da thunkit?

I was thinking that might be the only part that DID work... which would have to be kinda mixed news to the engineer in charge of that subsystem.

Then again, I also wonder if they would even have a destruct-mechanism. If it has to be enabled remotely, what are the chances that someone's jamming or "educated-guess" control interference signals might set it off?

Comment Re:EVery last one of those mountains are still act (Score 1) 251

Define active.

If, by active, you include old volcanoes which are slowly subsiding into the ocean crust, and will never erupt again, then yes, ALL of the Hawaiian "mountains" are still active volcanoes. By reasonable interpretations, however, 2-5 Hawaiian volcanoes are active, several are dormant, and several (many, counting atolls all the way to Midway, and many more counting seamounts all the way to Alaska) are extinct.

What exactly does it mean to be a "deeper" active volcano anyway? If the only molten rock is deep enough that it will NEVER reach the surface, and will simply cool where it lays, then I wouldn't call that an active volcano.

Comment Re:Not granite... (Score 5, Interesting) 251

Read the article. This magma chamber is NOT apparently basaltic, and has much in common with magmas that produce granite. 67% silica content - which is very uncommon to see in anything on the surface here in Hawaii.

That said, the important thing isn't probably going to be understanding how volcanoes in other parts of the world work, but just in how this volcano works. That won't get as much funding as studying "how continents originally formed" or other highly derived hypotheses that this site might generate, so the geologists are focusing on what sounds good to people OTHER than Hawaiians (who are generally against messin' with da aina anyway).


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