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Comment Re:$11M v $42M, before anyone asks... (Score 1) 102

This is DARPA... It's been a LONG time since they've ever actually paid for development through final production.

Their strategy is to pay for initial technology development and proofs of concept, and then encourage (and probably help) to find a government customer who actually wants a product based on those technologies.

So the timeframe for a real product winds up being much longer. And the final bill to the taxpayers, much higher.

Comment Re:What's the point? (Score 1) 289

The A-GPS used by the 2G is subpar to true GPS.

The 3G and 3GS HAVE true GPS that maybe be operated standalone or assisted. Its accuracy is equal to most any other handheld GPS unit, and the assisted portion allows faster time-to-fix than standard products.

Which the 3G is missing that makes turn-by-turn difficult is a compass. Most turn-by-turn devices have a digital compass, which allows detecting that you've completed a turn an instaneous result. Without a compass, one has to depend on consecutive positioning calculations to detect that you are indeed moving in a different direction now (accumulating enough readings in the new direction to rule out precision error).

The 3GS DOES have the digital compass.

However, even in the 2G and 3G, one could use the accelerometer to confirm a turn. It requires using more than just CoreLocation in the apple SDK, but it's entirely doable and just as reliable an indicator as a digital compass.

I don't know if TomTom uses this approach in non-3GS devices or not, though. Some other apps do.

Comment Re:Come on GM, at least make the lie BELIEVABLE (Score 1) 1006

The conversion has absolutely nothing to do with cost of energy. They're calculating the amount of energy (measured in energy density units of gallons of gasoline) required to move the vehicle.

Basically, they're claiming the car requires 146Wh/mi for the somewhat arbitrary commute distance selected by the EPA. ((33705Wh/g)/(146Wh/mi)) = 230mpg (equivalent).

Granted, that works out to around 6kWh for a 40 mile commute.

Comment Re:"Blocks"? (Score 3, Informative) 172

Oversight? Hardly. It's damned expensive to produce unclassified content from a classified source.

By default, it is assumed ALL data generated by a classified source is classified. To unclassify any of that information requires a highly-tested, bulletproof-design of software that can be shown that in the process of declassifying any part of the data, it is impossible that something classified accidently got in there.

It's much cheaper to just leave everything classified at the same level as the piece of hardware/algorithms that produced it.

Comment Re:What's so hard? (Score 1) 321

In addition to the other commentaries:

Threading only applies to a subset of parallizable cases, on a subset of computing architectures.

You're not going to use threads to decompose a for loop doing simple non-dependent mathematic operations over a large vector. That's why the ugly vector operations were added to C for Alti-Vec/MMX/SSE/etc. It's another type of problem.

As long as software development is stuck in a cycle of having to invent new programming solutions for every new computing architecture, we're not going to see a whole lot of variance/advancement in computer architectures.

What is desperately being sought now is a much more generic way of indicating parralelism in code, that a compiler can then parralelize or no parallelize using any number of techniques, depending on the specific architecture it's compiling to.

People talk about fancy super-intelligent compilers, but that's not really what we're after now. They key is "merely" being able to concisely indicate data relationships (foremost dependency, but other attributes as well), which will open the door for any number of hardware and software innovations.

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