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Comment: Re:A legend of OS design (Score 1) 122

by Immerman (#47424785) Attached to: Prof. Andy Tanenbaum Retires From Vrije University

Ah, but is it the man or the deserving that the past tense is referring to? Perhaps he deserved a good retirement 20 years ago,but has since become a world-champion puppy-kicker and is no longer deserving of it?

And no, I don't actually know enough about the guy to make any such assertion.

Comment: Re:Skimmed through (Score 1) 87

by Immerman (#47424737) Attached to: Single European Copyright Title On the Horizon

I suspect the prank take down obstruction was intentional, surely the publishers lobbying for the law realized it could otherwise be easily used against them. As for good faith, I think that comes down to interpretation. It should only take one reasonable judge smacking down a "good faith belief" in the infringement of a clearly non-infringing work to establish new precedent - say one of the many cases where a similar title was the only common element. Of course IANAL, so perhaps "good faith" clearly allows for inflicting hours or months of legal difficulties on someone without doing even 2 minutes of common-sense confirmation first, but there seems to be considerably overlap between the concepts of "good faith" and due diligence"

Comment: Re:Not about jealousy, but ... (Score 1) 262

by tragedy (#47423627) Attached to: Dubai's Climate-Controlled Dome City Is a Dystopia Waiting To Happen

It's not necessarily as bad as you make it out to be. Let's say that you have a hemispherical dome covering 4.3 square miles, which I think is what the summary is trying to say. That's a diameter of 3766 meters and an interior volume of about 14 billion m^3, which is something like 17.15 billion kg of air. It's around 1000 joules per degree celcius for each kilogram. So, if you start with a very nasty 45 degrees celcius and get it down to a comfortable 20 degrees celcius, that's 428 terajoules. Obviously Air conditioning is not perfectly efficient. We'll assume an EER rating of 13 for the air conditioning, which may actually be a bit low for a huge commercial system. That's about 38%, so it would take 1.121 Petajoules. Let's say we're powering by gasoline. There's around 120 megajoules per gallon of gas, which translates to around 24 megajoules of electricity per gallon at 20% efficiency. So, that's around 46.7 million gallons of gasoline. Gas is around $2 a gallon in Dubai, so that's around $93.5 million. That's not very much compared to the initial construction costs of such a structure.
That's just the initial cooling, of course, there's still the matter of keeping it cool afterwards. With such a large structure, heat transfer from the outside is almost negligible with proper design. It's a huge number compared to a regular home, but it's very small relative the the massive volume. Then there's the heat generated inside. A typical human puts out around 100 watts of heat just by being alive, then there's all the lighting, cooking, and every other use of power. Guessing a kilowatt of heat generated per person wouldn't be too far off. From the numbers I've found, I'm estimating that they're expecting an upper limit of about 4 million people continuously (180 million visitors per year, guessing they will stay for a week, plus some permanent residents), so that's 4 gigawatts of cooling, or 126 petajoules per year. Going by our previous figures, that's around $10.5 billion dollars per year. That seems like a huge sum of money, but that's only $58 per visitor if they have 180 million per year (and it obviously scales down somewhat if they have fewer visitors).
These numbers are all rough, of course, and use naive assumptions about the shape of the dome, energy consumption, design efficiency, source of power etc. Obviously powering by gasoline would be crazy from an ecological standpoint, but there's an abundance of solar power available there, and the gasoline cost is just a stand-in. The numbers I gave are skewed towards the worst-case scenario, and they're still reasonable. There's nothing impossible going on there. There may be plenty that can go wrong with such a project, but making out the air conditioning in to a near-apocalyptic problem is a bit hyperbolic.

Comment: Re:the length of a 10-passenger limousine (Score 1) 54

by tragedy (#47416011) Attached to: Ancient Bird With Largest Wingspan Yet Discovered

It all depends on exactly which definition of "dinosaur" you use. Many, if not most, modern palaeontologists consider birds to be dinosaurs. Even if you use the traditional definition of dinosaur that restricts them to the Mesozoic, there were birds during the Jurassic and Cretaceous, so you would be saying that birds who didn't survive the era were dinosaurs, but those that did aren't. Which would make it weird for any bird species that survived unchanged well past the extinction. Would that single species be a dinosaur species up to the end of the Mesozoic, but cease to be right at the boundary? Would they just retroactively not be dinosaurs?

Comment: Re:the length of a 10-passenger limousine (Score 2) 54

by tragedy (#47404857) Attached to: Ancient Bird With Largest Wingspan Yet Discovered

That's not really just an idea from xkcd. Modern taxonomists group birds within the clade Dinosauria. Also, birds have tails, even if they're short. The tomia of a number of birds are also very toothlike. A number of dinosaurs, such as T. Rex had all kinds of adaptations to make their skulls lighter relative to their bodies.

Comment: Re:Not surprising. (Score 1) 688

by Immerman (#47399061) Attached to: When Beliefs and Facts Collide

All of science is based on the idea that something for which there is no evidence probably doesn't exist. Maybe gravity is actually based on the actions of invisible fairies, but unless and until you have *evidence* of the existence of such fairies the broader scientific community is going to say you're nuts. Similarly claiming the mind has it's roots in magic/soul/etc. Unless and until you have evidence that there is something outside normal physics involved, the default assumption is that there is not. Occam's Razor is not without it's flaws, but it is extremely efficient in trimming out the vast bulk of magical thinking from the scientific community.

Comment: Re: Any Memory?? what judge will go on just that? (Score 2, Informative) 415

by Immerman (#47398895) Attached to: Police Using Dogs To Sniff Out Computer Memory

Actually diddling kids has been standard practice in many cultures until fairly recently - it's only in the last few centuries that it's begun getting a bad name in the West. Hell - take the word "erotic", derived from the Greek "eros" - an emotion that was accepted to only be possible within the confines of a relationship between an adult man and a young boy - something that was openly embraced at the time.

Moral of the story: don't assume that your modern moral compass is of any use in determining historical reality.

Comment: Re:How was this to work ? (Score 2) 39

by Immerman (#47398823) Attached to: Free Wi-Fi Supplier, Gowex, Files For Bankruptcy

>Also, the only place to reasonably deliver advertising is on the landing page, once you pass this, there is really no way to deliver advertising in an efficient manner.

Come now - there's always the page of ads randomly inserted as a response to every tenth HTTP request. Wildly popular among users and generates much good will for the companies advertising.

Comment: Re:Actually makes good sense (Score 2) 674

by Immerman (#47398687) Attached to: TSA Prohibits Taking Discharged Electronic Devices Onto Planes

Which strongly suggests the existence of the TSA is pointless. As you say, and the professionals all agree - anyone competent who wants to blow up a plane will be able to do so unless stopped long before they get to the airport (and the NSA claims hey really truly have done so, but you'll have to trust us on that because we can't reveal the evidence). Meanwhile the TSA can't even catch the loonies who try to blow up their shoes and underwear - those have all been stopped by their own incompetence and/or other passengers. So the TSA is accomplishing what exactly?

Comment: Re:The point is lacking (Score 1) 133

Yeah, fixed the number error in a rely to Solandri - I was thinking insolation in the Southwest, which is indeed ~5kWh, but that's only directly relevant to solar-thermal uses.

I think you badly overestimate the summer-versus-winter variation, though I'll grant you that areas prone to long winter storms might indeed be that bad. But regardless - yes: the biggest problem with solar and wind is variability - the answer is some combination of storage and/or a high-efficiency long range distribution grid. Both of which are technologies under active development. After all, Arizona's insolation doesn't vary all that much over the year, and you'd only need to cover 60% of it with solar panels to provide the entire nation's energy needs. Double our PV and energy usage efficiencies and you'd only need to cover 14% of it, then you just need a superconducting grid backbone and a few days worth of batteries to power the nation.

Comment: Re:The point is lacking (Score 1) 133

Whoops, my bad - I was thinking insolation where I live in the Southwest: clear skies and lowish latitude translate to roughly 5 hours of peak solar equivalency per day, and the solar thermal systems which interest me as a tinkerer can easily approach 100% efficiency (1kW/m^2 at peak). At 16% efficiency that's still about 0.8kWh/day, but not nearly as impressive as 5kWh. On the other hand as you get into more overcast areas further from the equator the appeal of solar thermal increases, and high capacity thermal batteries (aka insulated water tanks) are cheap. Even in northern Montana a DIY thermal installation can pay for itself in a few years, and unless it's replacing wood or geothermal heating that's a big win.

But even PV isn't as bleak as you make out: let's use your number: 0.435kWh/m2/day w/current solar panels. Double that for the high efficiency panels to 0.87kWh. Then halve per-capita energy consumption to get in line with European efficiency:123.5kWh/day. That's still only 142 square meters per person. Three times my flawed estimate, but still not terrible. That's ~44,600km^2, or an area about 30% larger than Maryland, to supply the entire US with all its energy needs. Even with current energy consumption and cheap silicon PV we'd only need an area the size of Missouri to do the job.

And remember: the vast majority of that energy is consumed by businesses rather than individuals, and they are already beginning to roll out solar in a big way, because the $/Watt has already fallen to the point that it's notably cheaper than today's grid electricity over a 20-year amortization period, and businesses are accustomed to dealing with everything in terms of amortized costs. Let the price of fossil fuels keep climbing and the price of PV continue to fall, and it won't be long before PV is cheaper than burning coal on-site in many areas.

Power corrupts. And atomic power corrupts atomically.

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