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Comment Re:I think this has been done for some time now (Score 1) 80

See this page; the Campanile movie is from SIGGRAPH 97. How is Disney's tech different?

I saw similar technology at CMU in around that same timeframe (late 90s).

My memory will be obviously hazy here, but the resulting output was much less refined. A simple box-shaped house, for example, ended up having wickedly jagged walls. The technology showed promise, but it was far from realistic.

The Disney folks, while not inventing the tech itself, seem to have taken it a step further. Their key claim -- "Unlike other systems, the algorithm calculates depth for every pixel, proving most effective at the edges of objects" -- certainly jives with my memory.

Comment Re:There's just one thing to say. (Score 3, Informative) 100

They remain the property of NASA, and Bezos acknowledges as much: "If we are able to recover one of these F-1 engines[...], I imagine that NASA would decide to make it available to the Smithsonian for all to see. If we're able to raise more than one engine, I've asked NASA if they would consider making it available to the excellent Museum of Flight here in Seattle."

Comment This is newsworthy... (Score 3, Insightful) 327

... but not due to the results; this is an example of good, solid science coming out of a secondary school with limited resources. Given what I could read of the translation, I don't think this is irresponsible journalism at all -- think of it more as journalism on the state of education, not science.

It is, of course, an extraordinary result, and will require extraordinary proof. I suspect the claims will not be reproduced; at the same time, I hope these kid-researchers keep their interest level in this experiment up regardless of outcome. From this, they'll learn about experimental errors, uncontrolled factors, and -- most importantly -- to divorce their ego from their results. That last bit is perhaps the hardest for most scientists to achieve.

Comment Re:US Metric System (Score 1) 1387

Fahrenheit has its limit of 96 (not 100) set at body temperature (or what people believed it was before more accurate measurements), and 32 at the freezing point of water (i.e. an ice bath) for simple calibration of thermometers when they were being hand manufactured, since you can just split the difference between marks by eye in half to get to the single-degree markers.

More importantly, you can split the difference using geometrical constructions (compass and straightedge), which don't require another calibration source. The change from 96 to 98.6 actually occurred when the boiling point was recalibrated to exactly 212F. The actual original calibration points were 0F for the freezing point of a 1:1:1 water/ice/ammonium chloride mixture, 32F for a 1:1 water/ice mixture.

The development of the Fahrenheit scale is quite an interesting read, and it shows why the seemingly arbitrary points weren't arbitrary at all but dealt with the limited precision of the tools of the day. Not that this is any excuse to keep using it; we've have no need to split coins eight equal pieces for currency exchange and discarded our use of "pieces-of-eight" centuries ago, and a decimalized scale is so much more convenient.

Comment Servers or desktops? (Score 1) 102

I can see the benefit in doing this for desktops: most cases are non-standard, which means throwing it out when upgrade time comes around. I've toyed with the idea of making a standard ATX case out of paper pulp.

But servers? Ideally, they would be mostly caseless: think blades, or using the rack as the case; just slap a face on the front (to maintain proper airflow), and you're done.

Now, if we could make circuit boards more recyclable, that would be terrific. Though FR4 is already fiberglass; I suppose it could be dissolved in hydrofluoric acid and the metals recovered, though I have no idea how environmentally (un)friendly that is.

Comment Re:I miss Amigas (Score 2) 291

IBM PCs of the era had a similar option: attach the RAM to the ISA bus via an add-on card. Like the Amiga (and most computers of that era), the expansion bus was the processor bus (with a bit of buffering and maybe a tad bit of glue logic, but not much more).

As processor speeds increased, this became a problem. Many peripherals just weren't designed for the increased speed, so they divorced the bus speed from the processor speed by making it a fraction of the processor speed (ISA) or going asynchronous (Amiga Zorro III). This became quite pronounced with PCI (max 66MHz, even if you're running a 3.0GHz CPU); you can add memory onto the bus, but it will slow you down if you try to use it as main memory.

That doesn't mean it can't be used at all these days. The cluster computer folks have a concept called NUMA, or non-uniform memory access, where memory isn't considered necessarily equal in speed. Or you could treat it like a very fast SATA drive, provided you have the necessary means of keeping power to it during power failure events (or use it only as temp or swap space).

Comment Interesting bug, but don't get excited. (Score 5, Informative) 249

From Ted Ts'o's commentary, it's an optimization ("jbd2: don't write superblock when if its empty") gone awry:

The reason why the problem happens rarely is that the effect of the buggy commit is that if the journal's starting block is zero, we fail to truncate the journal when we unmount the file system. This can happen if we mount and then unmount the file system fairly quickly, before the log has a chance to wrap.

Basically, this optimization has the side effect of not updating the transaction log in this rare case. You can end up replaying old transactions after new ones, which will scramble metadata blocks. Given the rather unique conditions needed to hit this one, I'm not going to lose any sleep over any servers running without Ted's fix (though I'll certainly apply it once RedHat releases the patch).

Comment Re:Lift up that kilt and show us what ya got! (Score 1) 91

Aereo is doing this for their TV-to-internet service: each user gets his/her own antenna, in the hopes that it avoids legal issues. They create stacks of mini antenna arrays and set them up somewhere in Brooklyn. The wavelength for TV is 30 cm to 5 m, depending on the channel; both dimensions are much larger than the dime-sized antenna shown there.

How this exactly works, well, I can't exactly say. Although I am an electrical engineer, I have to admit that antenna design has always been out of my league.

Comment Re:lo (Score 3, Interesting) 673

The answer is simple enough....don't buy Apple.

I wouldn't quite say "simple" for a lot of folks, myself included. There are two reasons why I ended up going with a unibody MacBook Pro (2009-era) when my last laptop died: It has a decently sturdy build quality (much better than the Dell I gave up) and, when something goes wrong, I can take it to a human, point out exactly what's wrong, and say, "Fix it" rather than play phone and shipping tag with some contracted-out support company. At the time, upgradability didn't factor into my decision; it was just as upgradeable as every other system I considered. Since I purchased this machine, I've upped the RAM from 4 GB to 8 GB and swapped the rotational hard drive for an SSD. I've also had to use the Genius Bar to address a charging issue (1 hour of my time, vs. 2-3 months getting the run-around with Toshiba for my wife's previous laptop; there's a brand I'll never touch again).

(Mac OS? It's nice because it has the Unix command line utilities I'm accustomed to; Cygwin and Interix are clunky at best. UI isn't as nice as Windows 7, though.)

Now that Apple has removed the upgradability feature, I'm not quite sure where I'll go next.

This is why I've built my own desktops for over 15 years, because not only do I get a better quality system at a cheaper price, but I can have it the way I want it, not the way some OEM thinks is best.

Oh, I definitely build my own desktops. Laptops are a different beast, though; because the form factors are non-standard, it's difficult to find parts which play nicely. You can't just add a dedicated graphics card, for example, and the motherboard+screen+case are pretty much a unit (though your example of replacing the EEE's screen for a touch-enabled one is impressive).

Comment How old are these kids? (Score 4, Informative) 454

If they're under 13 (elementary and middle school age range), they're not allowed to access Facebook due to their terms of service and (in the US, at least) COPPA.

From Facebook's terms of service:
You will not use Facebook if you are under 13.

This is due to the Children's Online Privacy Protection Act, which requires verified parental consent before children can provide information to the website. While this does not impact you directly (that is, the FTC isn't going to knock on your door), you could get some heat from parents or administrators for allowing it at all.

Personally, I think the law is too draconian, but I wouldn't put my position in jeopardy to protest it.

Comment Re:Personally, I don't want them bigger (Score 1) 660

The main issue I have with devices in the size-range of the Galaxy Nexus (I have a Droid Razr Maxx) is the ability to grip and use it one handed (hitting buttons with your thumb). It's not something I need to do terribly often, but I had gotten used to this coming from 6+ years of owning a BlackBerry. If it were closer to an iPhone in size, I'd be ecstatic. (I'm still quite happy with it: a nice, long battery life, Gorilla Glass, and I can toy with Android development on it.)

That said, I don't see this as such a huge deal that I would go on a rant about it.

Comment Re:Hold on a second. (Score 4, Informative) 158

In the actual e-mail, it's about both size and change velocity:

Because I last week I thought that making an -rc7 was not necessarily realy required, except perhaps mainly to check the late printk changes. But then today and yesterday, I got a ton of small pull requests, and now I find myself releasing an -rc7 that is actually bigger than rc6 was.

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