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Comment Re:Missing the point a bit? (Score 1) 121

I'm not really in the target audience; but I know that sage, at least, can optionally use sage as a frontend to mathematica. I don't know how the feature sets compare; but if you are using the sage web interface it is pretty painless to interact with a copy of mathematica installed on the sage server; instead of, or in addition to, the OSS tools that it works with.

It may just be added complexity, there may be something that mathematica handles particularly brilliantly that the parent poster has in mind; but it shouldn't be terribly unpleasant done over the network unless your problem is computationally expensive enough that it would crush the rPi whether done locally or remotely.

Comment Re:The treaty says no such thing. (Score 1) 211

I'm not really sure how much staking-out of high ground is even possible until one gets closer to economic realization. Even if some treaty said that "Any touching of the asteroids is forbidden forever, with utter seriousness", one could safely enough do the R&D necessary to make grabbing them and chopping them up more practical; basically all the capabilities you'd need for asteroid mining can also be used for satellite launch, automation/robotics, improved astronomy and telescopes, and similar warm and fuzzy applications. The astronomy stuff would mostly fall under 'pure science', unless you can convince somebody that it will help detect ICBMs; but launch capabilities and improved robotics and remotely automated process research have a variety of plausible commercial applications even if the asteroids are off the table.

On the other side of the coin, highflown expressions of legal principle are usually given a great deal of latitude until they actually conflict with the interests of the nations that you need to sign and obey them. So long as the prospect is sufficiently science-fiction, anyone willing to spend a lot of time hounding UN delegates is more or less free to write whatever they want. Were somebody to step up to the table with a vaguely plausible plan, however, it's hard to imagine that they'd have much trouble finding a country large enough to be able to ignore the consequences and more than willing to do so in exchange for a cut of the take.

It seems to me that team lawyer wins more or less by default so long as the implementation isn't worked out(both because it won't actually be happening; and because there will be relatively little resistance to opining against it); but team mining will win more or less by default if they can actually make it cost effective; since laws national and international are bent, broken, or rewritten all the time for markedly less profitable(and much more ghastly) ventures.

Until that time, the posturing is symbolic(either banning the practice or laying claim to rocks you aren't already on course to intercept). If the law says nobody can do it; that will change once somebody concludes that they can turn a profit by doing it; and if I get myself crowned God Emperor of the Kupier belt now; I'll still have to get my tech up and running before somebody else does, or the claim will do me little good.

Comment Re:Linux gadget. (Score 1) 121

The answer appears to be no on the rPi. The BCM2835's USB port is OTG-capable, so it isn't master only; but I can find no mention of gadget device configuration actually being available. The CHIP is maybe: apparently OTG support was added in kernel 4.3; don't know how well it works, or whether the CHIP's mini-b port even has its data lines connected.

Comment Re:Is C.H.I.P. really sub-10$? (Score 1) 121

Whether or not they can actually keep the CHIP at $9, if the project does actually get Allwinner SoC support mainline and GPL compliant it would be a fairly big win. All kinds of low cost hardware is built on Allwinner parts; but the software situation is kind of dodgy, since Allwinner doesn't seem to care and the people making hardware cheap enough to use Allwinner SoCs really don't care.

With Rockchip and Mediatek in play, it's not as though they have a whole lot of room for 'mwahaha, loss leader and then suck the captive audience dry!' mustache-twirling, because the audience just isn't that captive and their parts aren't terribly special, though competent enough. It's hard to see any attempt on their part to make them more accessible as a bad thing, whether or not the intro pricing can be sustained.

Comment Missing the point a bit? (Score 4, Insightful) 121

While it is extremely impressive that one could do so(given that such power for such price was unheard of until very recently), it seems rather pointless to compare these two boards on the basis that you are planning on plugging in enough peripherals to use them as your next desktop. Aside from the plummeting cost and wide availability of ludicrously overqualified x86s; the most stripped down ARM SBC is obviously going to require costlier and uglier peripheral tangles than the less stripped down ones(the CHIP has no 'sibling' designs; but is similar to Allwinner-based boards from others; the rPi zero has otherwise-identical models that add the USB hub and ethernet for you, or slightly punchier options).

The only reason to go with either of these is because you have some more constrained purpose for which the low cost and small size make the difference. So, do you want HDMI support; at the cost of bringing your own NIC; or do you want the NIC; but HDMI as an optional extra? Depends on whether you are building a headless project or not.

The other matter is the software support; which is as yet an unknown. The rPi has some Broadcom blobs that are very, very, unlikely to go away; but benefits from a known, solid, supporting ecosystem. The Allwinner A8 is a bit of an unknown quantity: the project claims to be aggressively mainlining everything(which would be extremely attractive); but Allwinner's GPL compliance has been...haphazard...at best in the past; and the MALI-400 is ARM's toy, not theirs, so they have limited control over that. If the CHIP's aspirations bear out, then it will have the distinct advantage of working with mainline kernel and u-boot. If they don't, or do only in part, then the question becomes one of 'which slightly oddball BSP is better?'

Comment Re:Err, petrol is currently cheaper that diesel (Score 1) 184

Yes, it's been so easy to measure that it took years for anyone to realise what VW were doing... I'm afraid after VW none of these studies are really credible in any way.

People realised the basic problem for ages, they just thought it was due to the tests being unrepresentative of real-world driving - which they are, and is the correct explanation for most car manufacturers as far as we know. The studies are as valid as they ever were in terms of the effects they describe, which is that NOx from diesels in the real world is higher than the official test figures say.

Like diesels, petrols aren't nearly as 'clean' as anyone would like them to be,

No, but they're cleaner than diesel, and they're the most readily available alternative for cars. Heavy vehicles can keep using diesel with AdBlue and DPFs. Better to have a readily available "good enough" technology actually used on a big scale than a perfect one that's too expensive or otherwise problematic for widespread use.

not to mention being less efficient. They are just simply not an answer and the falling oil price scuppers it totally, no matter the propaganda.

How on earth does the falling oil price scupper anything? That will *help* the less fuel-efficient technologies, not hinder them, by reducing the cost of the inefficiency. Your statement doesn't follow.

The simple arithmetic is when you more throughly burn the fuel you get more emissions. That's the way the engine works

You're ignoring aftertreatment. It's OK to produce a pollutant if it's cleaned up before it gets into the atmosphere. Petrol catalytic converters are very efficient at removing NOx and have got ever better in recent years (diesel ones are not as the reduction reaction doesn't go in the oxygen-rich diesel exhaust). More "thoroughly burning" the fuel will, if anything, reduce emissions of hydrocarbons and carbon monoxide, as they're the products of incomplete combustion.

In any case, NOx is produced by high temperatures causing a reaction between the nitrogen and oxygen in the air. More "thorough" burning has nothing to do with it - crappy old carburetted cars produced plenty of NOx, despite having a large amount of incompletely burnt fuel in the exhaust.

and of course they're going to produce less than a diesel without a DPF, which is a downright bizarre thing to qualify that with. Remove the catalytic converter and filters and see what happens in reverse.

Not bizarre at all. DPFs don't block everything. Port-injected engines can produce less particulate matter than a diesel *with* a DPF, as can direct injection with appropriate design. It's just that that wasn't designed for until now because soot wasn't part of the petrol tests until recently (as old petrol engines produced so little of it).

In continental Europe where diesel is the same price or less expensive than petrol, which is what it should be as the fuel is cheaper to produce, the maths are quite easy to work out.

Indeed it is, and I was bored enough to do it once. The untaxed price of fuel at the moment (in the UK) is about 36p/litre vs 40p/litre for diesel (the tax is the same per litre, so the basic price of diesel is higher). For 10,000 miles a year that makes about £70 per year difference in fuel cost (diesel car getting 50mpg and petrol one about 25% less, which is typical. The difference is smaller for more modern petrols.). Nowhere near enough to justify the extra purchase cost. Even double that probably wouldn't be for most people. It's only the tax system that makes it so - why do you think diesels are far less popular outside Europe?

Hybrids are not only hellishly complex but they are incredibly expensive to maintain.

The Prius is one of the most reliable cars you can buy, so I don't know where this "incredibly expensive to maintain" comes from. Hellishly complicated? You're just replacing a starter, alternator, and complicated conventional transmission with two motor-generators, a NiMh or Li-ion battery and a simpler transmission (look it up, it's really quite elegant). More expensive, certainly, as the motors have to be much more powerful, but not really more complicated.

They're certainly more expensive than a diesel engine. Electric vehicles have far fewer moving parts and simply don't need the oils and lubricants a modern combustion engine does.

True, but the capital cost of the batteries is vastly greater than the cost of a few litres of lubricant oil every year. And all the non-engine parts will need maintenance just the same.

It's a question of where the future is if people really care about emissions and want something that is efficient whilst being cheap enough to buy

But they're not cheap enough to buy yet, that's the point. Maybe they will be one day, maybe not.

and especially maintain and there really isn't any more efficiency to be hammered out of the internal combustion engine. The best you can ever hope for in terms of efficiency for a combustion engine is 40% (being very optimistic) - and that's with a turbo, energy recovery systems and every piece of expensive technology you can throw at it. It really is over.

Diesel engines can already do better than 40% - and old diesels too, without all the complicated stuff. The pretty standard engine in the Prius can do high 30s. But again, why does a modest efficiency mean "it's over"? 25% is good enough if the fuel's cheap enough that the total cost of ownership is lower than the more efficient alternatives. And so far that's still the case - despite the huge taxes on fuel in Europe.

If it's complexity you're bothered about then I don't know how you can support the diesel engine. Modern diesels are hellishly complicated - turbochargers, DPFs, urea systems (in some cases), ultra high pressure injectors machined to insane tolerances. The old ones may have been simple, but not the ones you can buy today.

Once you start using heaters and air conditioning systems in a car the comparisons get even more unfavourable when it comes to petrols

That doesn't make sense, heaters use free waste heat (of which there's more with a petrol engine due to the lower thermal efficiency) and aircon is just an extra load on the engine, and will affect petrol and diesel similarly.

Comment Re:Err, petrol is currently cheaper that diesel (Score 1) 184

I'm afraid it does. There is an awful lot of NOx and soot that has appeared from somewhere, and the uncomfortable truth is that it isn't all down to diesel vehicles.

I'm more familiar with pollution in cities in Europe, but we've got a good idea of where the NOx comes from, as it can be measured easily from different vehicles. And those measurements show that diesels don't perform nearly as well on the road as they do in the lab (not just VW ones either), whereas the petrol ones do much better http://www.theicct.org/blogs/staff/laboratory-versus-real-world-discrepancies-nox-emissions-eu

Modern petrol/gasoline engines have essentially had to run hotter and become more like diesels to keep up with efficiency. More thorough burning of the fuel means more emissions.

The measurements show the opposite, with NOx for petrol engines going down and down. There is one area in which what you say is true - direct injection engines produce much more soot than traditional port injection ones, but still much less than a diesel without a DPF. This can probably be worked around by tuning the injection system or, worst case, adding a filter to petrol engines too (I think Mercedes has already done this on at least one model), so I don't expect it to be a problem for long.

The emissions card is all there is left to play, and that is bogus, they can never be as efficient as a diesel and trying to flog more life out of them with hybrids just makes them hideously expensive. Beyond the internal combustion engine and diesels it is electric vehicles. It's over.

Electric cars make "hideously expensive" hybrids look cheap. Combustion engines are hardly "over" - electrics account for a tiny fraction of sales. A diesel engine is also more expensive than a petrol one - if it wasn't for favourable tax rates and emissions rules in Europe they wouldn't be economic except for high mileage drivers. Efficiency isn't the be all and end all - total running costs and emissions are.

Comment Re:Less service? (Score 2) 480

I don't know how the expected lifetime service cost shakes down; but what the dealership cares about is the margins on the service and maintenance they perform; not the absolute cost.

I would suspect that battery swaps, while they involve a very expensive part, would be pretty unexciting for the dealer. Unless the manufacturer is extraordinarily tight-lipped, the price of the battery will become public knowledge; and the procedure for swapping it out(while it might require equipment that makes DIY impractical, depending on where the battery is located and what needs to be lifted) should be rigidly documented and leave little room for variation in how much labor you can bill for.

Somebody has to do the swap, and presumably they won't do it for free; but there is little room either for value-added expertise(as with problems that require diagnostic work) or just plain sleazy invoice padding(as with problems where the customer doesn't know the cost of the parts, or which parts are necessary, or what the expected labor time is); it's a rigidly scripted drop-in replacement of a single module.

Comment State the obvious, get flamed anyway... (Score 4, Insightful) 370

If anything, it seems like deGrasse came closer to giving team Space!!! what they wanted to hear than I would have expected, in that he left open the implication that nation states might develop serious interest in colonizing nearby rocks and would then very likely find themselves in need of contractors for various purposes; and enable some more fully private side activities.

The ROI of getting things into earth orbit is well established; and it has a correspondingly robust market, with more outfits clamoring to enter it. Satellites are all sorts of useful and need more or less continual replacement, repair, and so on. Nobody doubts that.

The technical feasibility of snagging asteroids and chopping them up is still in the more speculative stages; but that also has an obvious possible ROI if the technical challenges can be overcome.

The case for the moon or mars, though, isn't just a matter of corporate shortsightedness, it's a matter of "Please, tell me about the ROI, within, say, the next 250 years...". Planetary colonization would undoubtedly be cool; and might be something that a nation state would get interested in as part of a prestige contest(like, say, the last time we were at all serious about the moon); but nobody ever seems to have any plans, aside from vague references to Helium 3, for what would make lunar or martian living more cost effective than some sort of aggressive colonization of underutilized desert regions or something similarly unsexy. The bounteous iron mines of mars? The endless plains of razor-sharp, static-clinging, vitrified silicates of the moon?

Comment Re:Smart TV (Score 1) 150

The only real reason(aside from a pathological hatred of having your ATSC/DVT-B tuner not be inside your display) is that 'big monitor' becomes increasingly hard to find if you want something fairly low resolution but physically large enough to suit a biggish living room, signage application, or the like.

You can get 'normal' monitors up to ~32 inches, with 1920x1080 being fairly cheap, even at that size, '2k' and '4k' rather more; but offerings thin considerably, and what is available gets very pricey, if you want anything bigger(the nominally-34-inch ultrawide screens are also fairly cheap; but are a poor fit for even 16:9 video, much less 4:3).

When sold as 'TVs' by contrast, you can get 1920x1080 in pretty much any size from 24-ish inches on the low end, to 65 on the high end; with '4k' up to about 80 inches in the reasonably priced section; with prices rising steeply thereafter.

It really depends on your intended viewing distance. A 32 inch panel dominates a desktop; but can look pretty anemic in a larger room; and if you can even find monitors much larger than that, they are likely to be staggeringly expensive specialty items; which is serious overkill when you plan to be sitting far enough away that the pixels will be harder to see anyway.

Assuming a suitably close viewing environment, definitely, TVs suck; but if you really do need or want a big image(and not a projector); it's pretty much a matter of picking the 'smart' TV that will whine least when you never ever connect it to the internet.

Comment Re:Give me a dumb tv (Score 1) 150

I suppose that that's the one blessing of the relatively high cost of US market cellular data: it isn't yet economic for TVs to literally phone home if they are denied free internet access. The hardware to do so is chillingly close to be plausibly cost effective; but the cost of exfiltrating any nontrivial amount of data, or serving ads, is presumably still too high.

All programmers are playwrights and all computers are lousy actors.