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Comment Re:Does it really take so much computing power? (Score 1) 861

Trouble is, you tend to have to use realtime friendly CPU's when you do this stuff. So things like pipeline optimization, predictive branching, cache management, etc, tend to not always be present on CPUs that are designed for determinism. So realistically, I would not be surprised if the heaviest computing in that thing is done on a single core 500MHz-1GHz CPU, and the rockets aren't probably running anything fancier than a 100 MHz single core machine either. They may or may not have memory management in hardware (I know some higher end 1GHz SBCs I've worked with don't, they just have a single flat address space).

It's still way overkill for what it needs to do, but in order to get the cycle times down under the 10 msec mark (order of magnitude), you have to pick and chose what language you work in (anything with non determinism like Java or something with a heap like the C++ run time may well be a no-no), and you have to pick and choose which algorithms you implement.

The latest-and-greatest randomized algorithm you see in IEEE may not be suitable for realtime implementation because while the average time is 1msec, there exist execution paths which take 15 msec to run. So you're safer going with the sub-optimal thing that executes in 5 msec every time.

Comment Re:Too bad... (Score 1) 861

The PLO/PA under Arafat made the choices that lead to that situation. Go back and read through the mid-late 90's history of the conflict, and especially what went on in 2000. It's almost entirely a one-sided history of violent Palestinian provocation followed by increasingly violent Israeli response, not the other way around.

Comment Re:How much do missles cost anyway? (Score 1) 861

Rocket motors, servo actuators, casing... probably cheap. Ruggedized computers, comm equipment, on-board sensors, etc, can get kinda pricey. I'm actually surprised these things come in at 100k per shot considering the amount of high end stuff that has to live inside the missile rather than the ground station.

Comment Re:Patriot Failures (Score 1) 861

This is my justification for being a hardass about data types and mathematical proofs of correctness for critical sections of code. If your website crashes because you used a float when your should have used a double, or a double where you should have used a long long int, no one cares. If the clock on your process control gets screwy after a bit, then you have a physical problem.

Comment Re:Doesn't work for an invitation-driven conferenc (Score 1) 343

...led at least some non-white-male potential presenters deciding not to submit proposals.)

If true, then it's even stupider. Free people cannot condition their behaviour on that of the most offendible in the group. For the same reason that the entire education system cannot (K-PhD) be conditioned on the abilities of the stupidest portion of the population, and for the same reason that my income cannot be conditioned on the earning power of the laziest portion of the population.

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