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Comment Re:The problem (Score 1) 141

Quads can't, no variable pitch blades.

And you don't see the solution to that?

It's really simple. Regulators mandate safety standards so that - in real world conditions - you don't have cars constantly falling out of the sky due to failures or running into buildings. Engineers determine the designs to meet those standards. If they can't, they don't get to sell it.

Comment Re: Children and bathwaters (Score 2) 120

IQ tests are problematic, and are at best general indicators. And seeing as socio-economic conditions can and do influence IQ scores (see the Flynn Effect), trying to use IQ averages in populations to justify claims "whites are smarter thank blacks" makes IQ tests even more problematic.

Probably the best way to up general IQ scores in a population is to assure children get proper nutrition in infancy and childhood. So the real observation here is that IQ scores are probably measuring other phenomenon other than intelligence, making claims that some ethnic or racial groups are smarter than others pretty iffy at best.

Whatever the factuality of the Bell Curve, the Flynn Effect seems to counter it. Intelligence certainly has a genetic component, but it's probable that you won't really determine just how genetics influences intelligence so long as you have large segments of any given population who lack both academic avenues and basic requirements for academic and cognitive performance like decent food.

But hey, I get it, it's the age of the alt-right, where saying "Blacks are dumber than whites" is now apparently some sort of unassailable dogma, and where a previous generation's debunked or at least heavily questioned claims are brought back and again asserted to be absolute truth.

Comment Re:yes and no (Score 2) 97

The first computer I remember using in school was an Apple II, I think it was in fifth grade. I remember playing Lemonade Stand and Oregon Trail. When I got into high school, they had computer labs that were made up of Apple IIs, Apple IIEs and some Apple II clones. Didn't see an PCs until a few years later when I took data processing (basically dBase III) and "office procedures" classes.

My actual first introduction to computers was my uncle, who had a Commodore 64, and between playing with that and in Apple BASIC at school, I pretty much begged and pleaded with anyone would listen to get me a computer.

Comment Re:I agree, but not for the same reasons as Musk (Score 1) 141

Congratulations, you have it entirely backwards.

The maximum efficiency of a prop, in newtons per watt, is 1 / (v_wake + v_freestream), where velocity is in meters per second. The faster you're moving (the freestream velocity), the less thrust you get per watt. Which is why large props are more efficient (more air moved at a lower wake speed), particularly at low speeds, and same for high bypass jet engines.

Now, in terms of "energy per 100km" or "miles per unit energy", obviously a hover yields "infinite joules per 100km" and "0 miles per joule", because you're not going anywhere. But that's an entirely different situation than propulsive efficiency. If you want to start factoring in motion, then your cross section / drag coefficient / L:D ratio / altitude (and thus density) and so forth come into play, and the optimum speed comes down to a balance between a wide range of factors - the faster you go, the less time you spend flying, but your drag increases quadratically, and your prop efficiency drops (the rate of drop relative to the difference between the freestream and wake velocities). Airplanes maximize this balancing point by having extremely low drag coefficients (Cd), far less than cars tend to have.

Comment Re:EBooks (Score 1) 148

The way it was explained to me is that printing, particularly in an age of "just in time printing" is not the most significant cost in publishing. Whether you distribute a book in physical form or electronic, the process is much the same, in that you have to take a manuscript, edit it, and put it into a publishable form. Now while an epub file (which is just a glorified bunch of HTML, image and meta files zipped together) doesn't require the kind of typesetting that a print book does, it still has to work off of the final copy produced.

Now that doesn't explain all of an ebook's costs, and I do think there's some gouging going on, but it's not as high as we think.

Comment Re: Children and bathwaters (Score 2) 120

Because public schools are run by morons who are still stuck in 1950s in regards to assessing students. As it is, even with standardized IQ tests, the numbers have been rising in many populations, including African-Americans for decades, suggesting that what IQ measures isn't really raw cognitive capacity at all (ie. the Flynn Effect).

One of the biggest reasons for lower cognitive ability isn't genetic at all, but poor nutrition during the developmental years, and that's one of the reasons that socio-economic status has been viewed as a significant player in general and specific cognitive abilities. There's no doubt there's a genetic component, but like anything, genetics sets general parameters, and it is environment that takes over after conception. Considering that many ethno-racial groups in the Americas have not been equal beneficiaries of over all socio-economic improvements, that would strike me as a good reason for why we see phenomena like the Flynn Effect. But that's a rather dull explanation, and not one that allows some Neo-nazi to declare he's superior to African-Americans.

Comment Re:ebooks are friggin expensive (Score 3, Interesting) 148

I agree there's not really any cost savings, but I read ebooks largely for convenience. As to DRM, the only place it really fucks me up is graphic novels, which I have yet to figure out how to unlock, but for anything I buy off of Google Play, thus far a combination of Adobe Digital Editions 4 and ePUBee seems to do the trick. I appreciate that at some point that won't work any more, and then I may have to reconsider how I consume books (at the moment I buy a book, immediately rip out the DRM and then archive the epub).

Comment Re:EBooks (Score 2) 148

I like them for convenience. I've got an ereader on my tablet that syncs with the one on my phone. When I'm at home I'll read on the tablet, which has a much bigger display, but when I'm out, I can read the book on my phone. I find it convenient, and don't really read any fiction in real book form anymore.

Comment Re:Really? (Score 1) 141

The assumption is that if flying cars were common, there would be vastly more locations. As they basically function like helicopters (in most conceptions - VTOL), they need only something equivalent to a helipad, not an airport. Which is much cheaper and smaller footprint than an airport.

To get to the point of allowing takeoff and landing from, say, a driveway, you'd have to have a long track record of excellent proven safety, and levels of noise reduction that current technology doesn't yet support. It's certainly conceivable in the future, but is anything but a first step for companies working on flying cars today.

I personally view flying cars as pretty much inevitable (although not around the corner) regardless of whether or not they're pursued directly at present. Namely because of delivery drones. Businesses are not going to stop pushing for them because there's such an economic case for them (not having to drive a big truck around city streets, pairing trucks with drones to not have to go down each sidestreet or stop at each location, etc), and they'll advance the technology as needed to get approval - starting small. But economics will continually push them toward making larger and larger models, and the technology to get approval for those. And eventually you'll have models large enough to carry people around, wherein the question will inherently arise, "Why, exactly, aren't they carrying people?"

Comment Re:Not going to work (Score 1) 120

Oh fuck off you blithering moron. Advertisers have been pushing around their weight for fucking ever. Jesus fucking Christ, you couldn't even show an interracial kiss on TV in the 1960s without most of a network's southern affiliates refusing to broadcast the fucking episode, because their advertisers would freak out and pull their ads.

It's like people like you have lived in some weird bubble where you know absolutely fuck all about how the actual world fucking works. In an advertiser-supported platform, the advertisers are God, and if they decide that a topic is going to harm their brand, then they, as God, have the power to yank the advertising. Sometimes they do it for evil, such as trying to keep interracial kisses off the air half a century ago, and sometimes for good, as when they don't want their products associated with ISIS beheading videos or Neo-nazi fruitcakes. But they have the absolute authority to it, for better and for worse, and if you don't like it, start up your own video sharing service.

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