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Comment Re:Maybe voice activation is overrated? (Score 1) 168

BTW, the part about knowing who's going to use the door and who isn't is probably doable with cameras and enough processing power.

It is possible, and it has been built. A couple of colleagues in Sweden did just that for one manufacturer, more than fifteen years ago. The idea was to reduce the amount of heat lost from unnecessary door openings in winter, and to a lesser extent from cooling losses in summer.

It would recognize who was aiming for the door versus those that just walked past. It wasn't fooled by dogs or kids (would open for kids, but not dogs) or things like suitcases or prams. During development they built a version that would only open if you did the Vulcan hand sign thing.

But it was too expensive. Automatic doors are not a high-margin business - there's many competitors - and the actual savings did not make up for the higher price. The actual energy losses are pretty minimal for most shops, and door openings are usually not in error. Those that have a real problem with it tend to use revolving or double doors already.

Also, it didn't help that the shops might have needed permission to mount what is effectively a camera pointing out on the street.

Today the hardware would be cheaper, and cameras are far more acceptable. But from what I heard customer interest would still be small.

Comment Re:As someone with a masters in this -exact field- (Score 1) 271

If you are a true master, you should be able to explain concepts in a way that even a child can understand

This is, in a word, horse pucky. It's the same reasoning my niece uses to justify her anti-vaxxer beliefs: the quacks and charlatans she listens to are more credible than epidemiologists and immunologists because they're easier to understand. This is the real-life equivalent of the joke about searching for the $20 bill under the street light because where you actually lost it is inconveniently dark.

If it were true that a child could understand anything, there wouldn't be a need for education. You'd just find a "true expert" to explain, say, fluid dynamics to a random bunch of people off the street and then set those randos to work designing aircraft. Or cryptographic systems.

There's an unfortunate cultural trend to devalue anything that requires mental effort and dedication to understand as elitist bullshit. This is a dangerous development, especially when combined with our national vanity: ever since the Moon landing we see technological and scientific leadership as a birthright. It's not. It's something we have to earn, and continue earning every day by dint of hard labor.

The humbling truth is that real understanding in many things requires trekking a long and arduous road. It's a near certainty that you don't actually understand General Relativity; crude analogies about balls and rubber sheets notwithstanding. General Relativity is like a mountain that looks easy to tackle from a great distance, but the fact is it takes years of toil before you can even grasp how arduous the foothills of Mount Einstein are.

Comment Re:He's missing the point. (Score 4, Insightful) 148

It would be nice if people could learn to think in terms of threats that fell somewhere between "safe to ignore" and "extinction level event". Or could distinguish between "extreme and expensive" responses and "effective" ones.

9/11 could have been prevented by simple, conservative and inexpensive countermeasures. After 9/11 politicians droned on about how "9/11 changed everything," but the cold sober fact was that it in fact changed nothing. It just showed that some of the things sensible people had already been telling us to do (like reinforcing cockpit doors or getting agencies to work together despite institutional rivalries) really did need to be done. Instead "9/11 changed everything" became the rallying cry for every pet scheme that had heretofore been correctly dismissed as too expensive, hare-brained, or just plain dumb.

Which doesn't change the fact that something needed to be done. Here's the lesson I think we should take into this infrastructure debate: we should take sensible and conservative steps to secure infrastructure against terrorism now, before events put foolish ones on the table.

Comment Re:Good but... (Score 1) 120

Or... what if anytime anyone called a residential number, a nickel was transferred from the caller's account to the callee's account.

That wouldn't stop anyone from making a call where an actual person is likely to be involved; the labor costs for a three minute conversation would swamp that. But it would discourage people from robocalling a hundred thousand people in order to turn up a handful of suckers.

And the public wouldn't have to pay a regulator to try to track down these boiler room operations.

Comment Re:Agrument in favor of modularity (Score 1) 87

I don't have to do anything. Even stored under ideal circumstances li-ion batteries lose capacity.

What matter is capacity relative to demand. In a phone like the Droid Maxx from a few years ago with plenty of surplus battery the phone will still be usable four years later. But something like a Samsung Galaxy S6 barely has enough battery to make it through the day when brand new and is pretty much unusable two years later even under ideal conditions.

Comment Re:There's a lot more iron much closer... (Score 4, Informative) 300

And there's some twenty million tons of gold dissolved in the Earth's oceans. Jules Verne made it the source of Captain Nemo's incredible wealth.

To put twenty million tons of gold in perspective, all the gold that has ever been mined by humans totals up to about 180 thousand tons. To put in another perspective: sure, it's gold, but at a concentration of thirteen billionths of a gram per liter of seawater it's worthless unless you have unlimited time and energy to extract it.

That's the problem with asteroid mining in general. Until the cost of changing an object's momentum goes down drastically it's not worth doing. If Pysche were a 1000 kg block of pure, refined platinum (market price: $34 million) you'd be hard-pressed to retrieve it and return it to Earth at a profit. Which is not to say asteroid mining is a bad idea; but first things first: you've got to reduce the price of interplanetary propulsion by a couple orders of magnitudes. One thing that never happens in a sci-fi asteroid mining scenario is the hero worrying about running out of gas. Propulsion in stories is always practically limitless and free of charge. Real propulsion will never be that good, but it could get good enough.

Comment Re:Agrument in favor of modularity (Score 5, Interesting) 87

How much thickness do you think the extra outer layer of plastic adds to the phone? If it has to be more than a millimeter I would be surprised.

Personally, I think it has more to do with the fact the lithium ion batteries have a finite shelf-life than it does with thickness. That means in two years you need a new phone even if you never added any software to it and managed the battery recharging perfectly. Even if the phone had been sitting in a box all that time it'd have significantly less battery life.

Comment From TFA: (Score 1) 168

The patterns were a mishmash of unrelated structures that were as misleading as they were illuminating.

This pretty much describes the state of every branch of science after a major influx of new data. Just look at the maps of the world produced after Europe became aware of North America. Early maps sometimes show California as an island; and it's not because the cartographer is stupid; he just put the data at his disposal together into what was at the time a plausible conjecture. And in fact the problem might not even have been that he was ignorant. He may have misinterpreted some of the (at that stage) imprecise data he had to work with.

New information confounds. The detection and resolution of conflicts in data is arguably what science is.

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