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Comment Re:Scientific Computing (Score 2) 258

As long as we're comparing mysterious numbers*, let's take a closer look.
Future Chip:
38 GFLOPS / 2.7W = ~14 GFLOPS/W
Tesla K20x:
3950 GFLOPS / 235W = ~16.8 GFLOPS/W
Radeon 7970:
3790 GFLOPS / 280W = ~13.5 GFLOPS/W

So I'm not seeing a power advantage here. More questions: does the chip do double precision, and what's the rate? What's the memory bandwidth? Is there support for ECC/scrubbing, which is essential for Big Deal calculations? (The 7970 doesn't support ECC. The Tesla does, and it had better given the amount of money you pay for it.) I'd imagine the Future Chip would be a cheaper solution, but you're starting from scratch with the compilers when everyone else has a major head start.

So while I think a FSF Principles chip is a good idea, pitching it for scientific computing is a stretch.

*Future Chip numbers probably do not include memory power consumption, and are likely a optimistic extrapolation from the dual-core silicon. Radeon result is the unholy combination of AMD's published single-point FLOPS and the max power consumption from Anandtech's review. Tesla numbers are marketing numbers combined with TDP.

Comment Re:Unfortunately for Arduino (Score 1) 130

Thanks for the tip about Energia. My old robotics club bought a bunch of MSP430 Launchpads when they came out, but the software side of the equation was definitely lacking, especially for cross-platform development.

I'm also excited about the Stellaris Launchpad and hope that an open source command-line workflow will be developed. Should be fun.

Comment Re:My first thought... shuttle tiles (Score 4, Interesting) 184

Space-age materials are pretty amazing, but Fusion-age materials are at a whole different level. I think the community hasn't expressed to the public just how daunting the challenges are. Controlling the plasma is one thing, but engineering the plasma-facing components (PFCs) is a whole 'nother kettle of fish.

The so-called "first wall" is the interior layer of the fusion reactor. It has to stand up to neutron bombardment, but it also has to avoid shedding particles into the plasma. For example high-Z materials such as tungsten, molybdenum, and vanadium are interesting for their neutron tolerance, but if atoms scrape off into the fusion plasma they will radiate like crazy (proportional to Z^2) and drain a lot of energy out of the plasma. That's why they are testing a Be coating (Z=4).

On the other hand, you have divertors, which sit in direct contact with the plasma and basically hold it in place so it doesn't randomly hit the wall. These have to withstand a high heat load. I admittedly don't know much about divertors so I will stop there.

There's also the superconducting material in the coils of the tokamak to consider. Of course there's a whole bunch of neutrons flying around. But also but it turns out that a lot of the issues with superconducting magnets are mechanical in nature. The HEP community has figured out how to build SC magnets consistently, but I think the magnets needed for a tokamak are quite different.

There is supposed to be a International Fusion Material Irradiation Facility, part of the ITER project (and basically a consolation prize to Japan), that will provide intense neutron beams for materials studies. But I am not really sure what the situation/timeline is for that given the funding problems ITER has faced.

Comment Re:Flywheel (Score 1) 52

Define practical; it doesn't get much simpler than a weight on a servo. In contrast, how much torque can you get from a small compact flywheel and how much is it going to cost? How quickly can you regeneratively brake it with decent energy recovery?

(You might be interested in this control-moment gyro controlled ballbot.)

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