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Comment Re:Do we want to know? (Score 1) 143

Yes, since even with current technology it might be feasible to avoid the collision if we know its trajectory decades in advance. For example, if a probe flies close to the asteroid, the gravitational pull of the probe will alter the path of the asteroid a tiny bit, but a tiny bit can be enough if it happens a long time before the asteroid gets too close to earth.

Comment Re:How to deal with compiler bugs (Score 1) 241

I see internal compiler errors (assertion-style) and crashes quite regularly, as in multiple times per year. Valid language constructs being rejected or invalid ones accepted happens too, although I don't know the language specs well enough to spot most of those. And occasionally a code generation bug (I can remember two from the last 10 years).

How often you find compiler bugs depends a lot on what part of the compiler you're stressing: you'll encounter more bugs on MIPS than on x86, for example, since x86 has far more users. And if you're trying new C++11 features it's far more likely you'll see a bug than when you're compiling plain C.

Comment Re:How to lose time and sanity (Score 1) 241

My e-mail address was harvested years ago: I have to rely on spam filters anyway, so I don't really worry about publishing it in bug trackers.

Registration is a pain, I agree. However, on a project that I participate in (openMSX) we did decide to stop accepting anonymous bugs reports, since the majority of bug reports lacked essential information to be able to reproduce the bug. If there is no way to contact the user who filed the bug, the only thing a developer can do is close it as non-reproducible ("worksforme" in Bugzilla - a very poor choice of words in my opinion).

How well a project responds to bugs differs a lot per project and also per individual bug. Some are fixed years later, some within a day. Some are marked invalid even though they are valid, others are indeed invalid or are duplicates. The compiler projects (GCC, LLVM, Intel C++) have been relatively good with responding to my bug reports, so I will report new bugs to them when I find any. For some other projects, I don't bother anymore unless it's a data destroyer or security issue.

Comment Re:Tesla, here we come (Score 1) 338

Trolley buses are operational in more than a few cities without supervision or separation. I don't know if the system could scale to a much larger number of vehicles and more routes, but I don't think safety would be the blocking issue.

What about wireless charging: is it feasible to charge a car while it is moving? It might be cost effective on busy roads; cars would still need a battery but a smaller capacity would suffice if it can be recharged while driving.

Comment How to deal with compiler bugs (Score 5, Insightful) 241

If you suspect the compiler is generating invalid machine code, try to make a minimal test case for it. If you succeed, file a bug report and add that test case; the compiler developers will appreciate it. If you don't succeed in finding a minimal test case that triggers the same issue, it's likely not a compiler bug but an issue in your program in some place where you weren't expecting it.

Comment Re:Title is misleading (Score 5, Insightful) 510

The thinking is that there isn't enough useful work to be done.

There is plenty of useful work to be done: children would benefit from smaller classes, the elderly would like more attention, cities could be made prettier, there are lots of things that can be researched. The problem is that no-one is willing to pay for those things: we're always looking for lower costs, lower taxes, not higher quality of life.

Comment Re:proofread a few lines only? (Score 1) 148

Wouldn't they have to check the systems anyway after discovering they were vulnerable? A break-in points out vulnerabilities in a system, but it is not the cause of those vulnerabilities and if one person can break in, others can as well.

If someone else had found the same vulnerabilities earlier and alerted them without breaking in, would that person be charged for the costs of reviewing the systems?

Comment Re:Doesn't make tech or economic sense (Score 1) 735

The payback period for solar panels is measured in decades.

That depends on how much sun hours you get, whether you can install the panels at a good angle, how much you pay for electricity and whether there are subsidies (either for installation or a feed-in tariff). I've heard from several people who did the math for their own home that their payback was less than 10 years.

Who lives in a house that long? The resale value of the house is not increased by solar panels, either.

Panels typically come with a 25 year warranty and while their efficiency declines over the years, they'll still be producing a significant amount of power after those 25 years. If you can provide numbers showing how much the solar panels save a month in electricity for this particular house, I doubt all potential buyers would ignore that advantage.

Comment Re:Doesn't make tech or economic sense (Score 1) 735

4. What would the batteries cost (taking into consideration substantial increased demand for rare earths, etc)?

For a home, I think lead-acid batteries would suffice: you wouldn't need particularly light or space efficient batteries.

6. Compare that cost to the installation of a conventional generator, either gas/diesel powered or natural gas/propane powered

If you look only at providing emergency power, a conventional generator is probably cheaper. But solar panels would produce power all year long, reducing your regular electricity bill. And it doesn't have to be all or nothing: you could install some solar panels and during outages you could then cope with a lower capacity conventional generator.

(and I'll grant you some appropriate 'market trade rate' penalty for the carbon produced by the generator.)

Unless you have outages very often, I doubt the amount of carbon output by the generator would be significant.

Comment Re:Solar panels are cheaper but the rest isn't (Score 1) 735

TV/cable box/modem/router comes out to around 300 W (assuming flat-screen).

During a power outage, would there still be a signal for your cable box or modem to receive? I don't know where the last distribution step gets its power from, but if it's from the same grid as your house, it will be down too during an outage.

Comment Re:Match Your Power supply to System Power Reqs (Score 3, Informative) 328

If you look at efficiency graphs, you'll see that power supplies are typically the most efficient under moderate load: at low and high load the efficiency drops. A typical desktop or home server is idle most of the time, so idle efficiency will have a big impact on the total efficiency. If you over-dimension your power supply, your idle load might be 10% or less of the max rating, which is far from the optimum of the efficiency curve.

I'd recommend getting a power supply that can deliver a bit more than what you need, for example 450 W if you think you need 350 W max. A bit of margin is useful since you might not have found the actual worst case or you might want to add components later. Also it avoids poor efficiency at the high side of the curve when the system is under load.

Comment Re:Geode (Score 1) 464

No, this is an actual low-power CPU, not a desktop part. Wikipedia does mention rebadged Athlon XPs being sold as "Geode NX 2001", but there were real Geode NXs as well.

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