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Comment Re:Hardware better? Matter of judgment (Score 1) 85

...Great comments, especially WRT the UBEC. My work is always in a lab environment (or at home, where I use beefy USB chargers...), so it never occurred to me to look toward the RC world for an inexpensive DC-DC converter. Thank you for that!

The RPi is not designed for industrial application, and every one of the characteristics you cite, while being important for "pro-grade" product performance, also add cost that is unnecessary for 99.9% of Pi use-cases. Professional engineering time (that's us...) is precious, so we don't screw around with toys for delivered production hardware. The RPi, Odroids, Pines, Pi-clones, even the Beaglebone Black are all fabulous toys that we use to support diagnostics, lab automation, etc: If a $4.99 SD croaks we image a new one and we're back in business.

Industrial strength hardware (fanless industrial PC) costs about 20x the toy hardware: about 700-1000US but it's still fabulously cheap compared to the way it used to be. (I won't get into the ugly details of trying to talk my management into getting rid of VME hardware and 25 year old designs...)

Especially when combined with trick like RAM-resident root and tmp filesystems, EXT3/EXT4 on modern high-endurance flash is fine, as far as I can tell. I've run endurance checks of our current CF cards (1 or 2 gig, extended-endurance) and they are still just fine after 10-15 years of simulated activity. Our product uses flash only for logging and vehicle reporting. Modern wear-leveling and larger media let us forget the whole endurance question. NO more JFFS2! :-)

Comment Hardware better? Matter of judgment (Score 1) 85

Personal note: I have and use Odroid -U2, -U3, -C, -C1, -C2, RPI2, RPI3, and a UDOO (original backer), mostly as micro-servers. I don't require much customization and as long as that remains true, I find them to be great machines.

The Odroids are definitely better hardware, but the story gets more complicated when the question of kernels (and the binary blobs needed for media) are updated to mainline. I've heard but not verified that the original Exynos CPUs in the Odroid-Ux are supported by mainline kernels.

The Allwinner chips in the Pines, Banana Pis, Orange Pis, etc. lack complete HW docs and need critical binary blobs (At least the Allwinner H8 has long needed a DRAM controller library blob, for example). If Allwinner were to clean up their documentation and make truly complete hardware docs available, then the overall product would be better than RPi. Until then, RPi support is so much better than their competitors that it overwhelms the otherwise obvious performance advantages.

Quoting from

However, the support isn't complete for the Allwinner A64 and is blocked in part by lack of proper documentation. Andre commented, "Due to a lack of official documentation and hardware availability this doesn't go any further at this moment."

The Allwinner A64 is comprised of the less-powerful Cortex-A53 cores, supports H.264/H.265 video decoding, and is widely talked about as being the "$5 ARM SoC." Hopefully this mainline kernel support will get figured out in time for the Pine A64 shipping.

Comment Re:Short-term numbers versus long-term (Score 2) 130

I'm not up on state of the art on computer image/object recognition but the experience I have from about 10 years ago leads me to believe that...

Others have already responded to your other points, I just want to point out that experience from 10 years ago tells you basically nothing about the state of the art today. Deep learning methods have enabled dramatic progress on exactly the class of pattern matching problems that includes computer vision.

Personally, I still think that LIDAR is inherently superior to video cameras for this task, but Tesla's numbers are impressive, and prove that while their system may not be all that it should be, it's already better than a typical human driver -- at least than the typical Tesla buyer (note that I have no reason to believe that Tesla buyers would be worse than average drivers, but the possibility shouldn't be ignored).

Comment Re:Whitespace takes the most space (Score 1) 175

But what is the value of an algorithm that you can't actually execute?

In the practical world, language efficiency actually matters and is a reasonable thing to discuss.

Sure, that's true. But it has no bearing on the question of whether a language can accurately be called Turing Complete -- and Turing Completeness also matters, because it defines the class of algorithms that can be implemented in the language. What's the value of an algorithm that you can't implement because the language lacks the necessary expressive power? Except in very limited circumstances, Turing Completeness is a prerequisite. Without it, there's no point in discussing efficiency.

Comment Re:You need to do a bit of research. (Score 1) 140

Star Trek Continues also violates those same guidelines (high-quality props/sets/uniforms instead of toy-store quality items, professional acting/directing/scriptwriting

Have you seen Star Trek Continues? Cheesy plots, lousy acting, terrible effects and you can't tell me their props, uniforms and sets don't look like toys.

It's like a low-budget 1960s vision of space travel.

Comment Re:Whitespace takes the most space (Score 1) 175

To be considered Turing-complete, a language must be able to simulate a Turing machine - and that's actually impossible, since it can never meet the "infinite tape" requirement.

Languages are not machines. Languages have no memory limitations, and therefore have no trouble simulating a Turing machine.

The fact that we run code written in those languages on finite machines does not change the Turing-complete nature of the languages.

Comment Re:He's missing the point. (Score 4, Insightful) 132

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) 113

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) 86

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) 287

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:Now lets see. (Score 5, Interesting) 1450

You might be interested in reading "American Nations: A History of the Eleven Rival Regional Cultures of North America", by Colin Woodard. The author argues that there are 11 distinct cultures in North America, which don't align neatly with state (or even national) boundaries, and that US politics is primarily a competition between two shifting coalitions of these 11 cultures, coalitions anchored in the Yankee culture (Democrats) and the Deep South culture (Republicans). One value that both of those cultures hold in common is authoritarianism, though of very different forms.

Yankeedom is built around and values a communitarian form of authoritarianism, derived largely from its Puritanical heritage. Even though the religious aspects of Yankee Puritanism have gone away, they've been replaced by a secular form of the same thing, which is the notion that while it's critical that the people as a whole have "independence", meaning they can form their own assemblies and regulate themselves, the individual should willingly subjugate his or her own will to that of the community. In Puritan days, this was severe; almost any form of disagreement with the community's religious and social values resulted in severe punishment. Individual freedom was not valued, and tolerance for alternative views was extremely low. Also, Yankeedom reveres education, and therefore the fruits of education, including progressiveness.

The Deep South is built around and values a hierarchical form of very strict authoritarianism, derived from that region's slaveholding culture, which enabled it to establish an essentially feudal model of lordly manors occupied by elegant idlers, supported by masses of lower classes. The southern planters placed tremendous value on "liberty" but it was the old Greek and Roman notion of liberty, which is available only to those at the top. The south took the "lower classes" notion a bit further than feudal lords with their serfs, but the southern class-based society wasn't just "planters" and "slaves", there was also a large underclass of what we might now call white trash, which was also expected to be subservient. What's perhaps odd about the old Deep Southern notions of hierarchy is that they were so deeply embedded in the society that although the underclasses chafed a bit, they also grew to expect a strong hierarchy and to respect their aristocratic leaders.

So, the two core cultures around which our political battles revolve are both authoritarians. Their allied cultures are less authoritarian, but it's the core cultures that hold the whip hand. In particular the left coast is very big on individual freedom and self-realization, but also has its roots in Yankeedom, including the trust in education and progress, which makes is a natural ally of the Yankee culture even though they disagree on individual freedom. Similarly, the far west culture is very libertarian but allies with the deep south because of its opposition to Yankeedom, rather than because it likes the southern authoritarianism.

Anyway, that's a flavor of what's in the book. You probably won't agree with all of it (I don't), but a lot of it makes a great deal of sense and I found that it really illuminates my understanding of the major political dynamics in the US, and has helped me understand why there is this strong streak of authoritarianism in a country that purportedly values freedom and independence.

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