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Comment Re:Great Idea (Score 1) 207

I've seen numbers like this for many countries, and I wonder if it's a side effect of giving an English-language test such as WISC to a non-native speaker? I suspect this because at 80 a personal qualifies for special ed in my (US) state, so this seems doubly suspect. Finally, the standard deviation is, by definition, 15.

Comment Baumol's Cost Disease (was: Re:No ) (Score 2) 537

The real answer is Baumol's Cost Disease, and it's why all services get expensive faster than overall average inflation. It's also why products get expensive slower than overall inflation. $6 T-Shirts at Sears are cheaper, inflation adjusted, than they were when I was a kid in the 70s (6 bucks today was 2 bucks in 1981 and pennies before 1974). Meanwhile, have you hired a couple of musicians for a wedding lately? Freaking expensive. Education is a service, not a product, and there have only been the slightest productivity improvements. The National Science Foundation and the National Institutes for Health set the overhead rates, and they've barely changed since the early 90s. Incidentally, the number one driver of university costs has been faculty and staff health insurance - like every other labor-intensive business.

Comment Re:What's the point of Western Union? (Score 1) 115

The big business doing this now is Wal-Mart and their "Woodforest Bank" branches inside the store - deposit in one town, withdraw in another. Fuel is still mostly bought, and loads are usually still paid for with cash, especially among independents, but most towns have a Wal-mart and drivers are rarely going down the road with $3-4K in the cab anymore.

Comment I went reading some of the specs... (Score 1) 292

I actually took a few minutes and skimmed some of the online training modules that USDOT put out for developers. There are problems, and they "sort of" admit to them. If I read this correctly, there are only ~105K possible keys, though I'd love to be wrong - otherwise this should fall to a brute-force attack in seconds. Just slam on your brakes, record the outgoing packets, and try every key until one decodes as "putting on my brakes, dude!" And now you have enough information to force any car to let you merge in, whether the driver wants to or not. Which, heck, might actually improve safety. I don't know. Could go either way.

As far as privacy, it's still pretty weak (=totally cracked). They aren't recording the MAC addresses of the cars per se, or so they say, but you could from first principles tell what factory a car came from and its approximate date of manufacture. That's useful - narrows it down to a manageable number of vehicles. Or just passively monitor an intersection with a license plate reader and record every "putting on my brakes, dude!" message. Now you have a table of license plates and MAC addresses. I can't see, frankly, that licence plate reader vendors won't sell this as an optional feature for a modest additional charge.

A big problem, and one discussed elsewhere, is that re-keying this thing is going to be a pain. It doesn't support over-the-air keying, and the intent is that a dealer will periodically re-flash new certificates/keys. That's a tall order. For this to work, cars will have to accept some pretty old keys (insert stars wars joke about older codes but they check out, above), increasing the odds they'll have to accept previously compromised keys. Which will probably be had by dumping the flash.

Anyway, the layer 1 and 2 protocols over the air are 802.11p, and what looks like a quasi-layer-3 is IEEE 1609. So get started.

Another commenter has asked about GPS errors. Looks like the standards explicitly support a very-short-range form of differential GPS and I wouldn't be surprised to see some sort of localizer used to reinitialize a Kalmann filter at some point. Pretty easy these days.

Comment Commercial, production laundry operations (Score 1) 139

Same thoughts here - just take a moment and enjoy it at home, but... I used to work for a company that made apparel. There is a plant in the deep south with washing machines the size of dumpsters - they wash 288 jeans at a time. Over 10,000 pieces are washed, dried, pressed, and folded a day. People stand there and manually turn them wrong-side-out and then, after laundry, turn them back again. They have to check the pockets to make sure there isn't any pumice left in them from "Stone Washing" - the rocks will mess up an iron. Extremely low-tech, labor intensive. Most of it is done in Mexico, except during droughts when it's hard to get enough water there (I'm not making this up), so they keep the operation in Alabama running all the time and they just add a couple of shifts during dry weather. A jeans-folding robot would need to come in pretty cheap so its Net Present Value would be less than minimum wage. Wild guess, maybe around $10K would be the breakeven point.

Come to think of it, with Alabama in record drought right now, I wonder if that laundry is running? :-)

Comment Re:GPS clock (Score 1) 291

The cool thing about CDMA is that it won't work without precision time standards in each of the base stations - i.e., GPS receivers with antennas fed through known lengths of feedline (or, alternatively, GPS receivers with known lengths of wire providing a 1 pulse per second reference). Net result is that CDMA can give sub-ppb time reference, and it works great indoors, too. Probably overkill for getting the kids up in the morning. :-)

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