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Comment Re:Another breakthrough! News at 11! (Score 1) 218

Twenty-nine years ago, I read about a breakthrough in battery chemistry that would make the common NiCd battery obsolete: the new chemistry had four times the capacity, could stand ten times as many charge-discharge cycles, and had no memory effect.

In the decade and a half that followed, I read about a number of other miracle energy-storage technologies: hydrogen, methane, methanol, and ethanol fuel cells; sodium, zinc, and lithium battery chemistries, and a number of other breakthroughs. None of them ever seemed to turn into an actual product I could buy, though.

I kept following that chemistry I first read about in 1988, seeing it pop up from time to time in uses such as electric vehicles or laptop batteries, but never in a form I could make use of. And finally, in 2003, I was able to go to a store and buy a set of those NiMH batteries to use in my digital camera.

Comment Re:Great for 10% of the population (Score 1) 220

Nuclear power has ramp-up and ramp-down times measured in hours or days. Because of this, it is strictly a baseload power source, just like coal. For peaking power, you need hydro, natural gas, or storage.

(Solar and wind are strange critters from a load-management perspective. They have the response times needed for peaking power, but not the availability.)

Comment Re:My kingdom for an easy software reinstall tool. (Score 1) 172

May I recommend Gentoo? The list of user-installed packages sits in /var/lib/portage/world, so re-installing on a new system is a simple as copying that file over and running "emerge --emptytree world".

(And then waiting a few days for compilation to finish, but then, if you weren't patient, why would you be running Gentoo?)

Comment Re:cost/gflop (Score 1) 68

RPi: $35 per node * 64 nodes = $2240

i7-4790: $500 per node * 64 nodes = $32000

If you're testing cluster-computing algorithms, it doesn't really matter how fast your nodes are, but there are situations you'll encounter with a real networked cluster that you can't simulate on a single compute node, no matter how fast it is. It's much like how you can use multitasking on a single-threaded processor to simulate a multicore processor, but there are entire families of contention issues you'll never encounter.

Comment Re:A sense of scale (Score 1) 24

Somebody is certainly missing a sense of scale.

Traditional Earth observation is done using a small number of satellites at a large distance, traditionally in geostationary orbit (35,786 km away). Using a large number of satellites in low orbit (300 km away), you can use low-power transmitters and commodity cameras. Sure, without cooling, you lose the thermal IR range, but in return you gain a great deal of resolution in the other bands.

Comment Re: Relays, not exit nodes (Score 1) 80

Let me ask you this, since you obviously didn't think about it...if Tor is so good at protecting privacy and traffic, how does the DoJ know what percentage of ANYTHING is going through it?

That's easy: you set up an exit node and watch the traffic going by.

Tor only promises to protect the data as it travels between your computer and the exit node. If you want protection after that, you'd better use SSL.

Comment Re:I actually warned the FBI... (Score 3, Informative) 110

You alerted them to actual spam.

The purpose of the suffix was to evade simple subject-line spam filters, while the "word salad" was an effort to evade word-classifier spam filters by drowning out the "spam-like" words with "non-spam" words, or to poison the classifiers and render them useless by loading up the "spam" wordlists with words that usually appear in non-spam messages.

Comment Re:I've got an idea !! (Score 2) 248

Parachutes don't have the accuracy needed to land on a barge, and splashing down in the ocean means complete disassembly to get the residual salt off all the parts.

The Shuttle SRBs could do parachute recovery with ocean splashdown because they consisted of a small number of very large parts, and needed pressure-washing to get the fuel residue off anyway. Taking a liquid-fuel rocket apart is a much harder task.

Comment Re:I'm amazed (Score 1) 169

from your figures it appears your script is including the theoretical purchase price of music that Pandora chooses to play at you rather than just the musicyou actively selected. I mean it could play something you don't even like or would ever buy but your script would still include the cost.

I've got statistics on that, too. Pandora is 99.65% accurate at picking music I like (by play count), or 98.03% accurate (by track count). Doesn't change the cost by much.

What about the extra hidden cost of your internet connections themselves and the necessary extra bandwidth usage?

The amortized cost of my Internet connection probably doubles the effective cost of Pandora, but even if the entire cost were added, it would still be many times cheaper than the iTunes cost.

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