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Comment Re:In this house we obey the laws of thermodynamic (Score 2) 145

It's not the ambient temperature of air that's key here, it's the ambient temperature of space, which is about 2,7K.

All objects are constantly radiating energy and receiving energy back from other things that are radiating. When two objects in radiative exchange are roughly the same temperature, this balances out. But when one is hotter than the other, the hotter one loses more energy than it takes in, and vice versa. And it's not just a little difference - radiative heat loss is proportional to the absolute temperature to the fourth power, that's a pretty big exponent. So when you're exchanging energy with space, which is so cold that it takes very sensitive instruments to be able to measure *anything*, well, that heat is simply lost.

You can see this effect for yourself by noting how cloudy nights are usually warmer than clear nights. Clouds are cold, but they're not as cold as space!

The effect of the combination of radiation, absorption, and reflection, with different band peaks for each phenomenon, manifests itself in atmospheres as a greenhouse effect (positive or negative) versus the radiative equilibrium temperature.

Comment Re:In this house we obey the laws of thermodynamic (Score 1) 145

This "modulation" happens all the time, few things in this universe are true blackbodies, most prefer to radiate in specific bands. They're apparently using a material that tends to radiate only on one narrow band at regular earth temperatures.

Not sure how much benefit this provides to the building owner, to the point that they'd be willing to cover their building in hafnium-and-silver coated panels, rather than just white paint...

Comment Re: haven't been following... (Score 1) 189

Does anyone actually have problems with scratching of the latest generations of gorilla glass? I've had my Xperia Z2 for over half a year and because it has a glass back as well as front it makes it less risky to try scratch tests, so I've done it a number of times and let other people try to scratch it, and nobody has ever succeeded. I'm sure if you put a diamond to it you'd scratch it, but short of that, I can't see why more scratch resistance is needed.

Now, *crack* resistance, they could use good improvements in that. : But from reports the sapphire wasn't that crack resistant.

Comment Re:Alive and gobbling (Score 0) 189

Surprised you haven't gotten any "but animals eat meat!" comments.

Animals also commit petty murder and mass rape. I like to think that we have the intelligence to choose to not have to imitate the behavior of other animals and decide our own path. And fortunately, we have a digestive system which allows us to make that choice when it comes to our diet.

Comment Re:What's with turkey anyway (Score 2) 189

Swans can literally kill people - a guy died just a couple years ago when swans attacked his boat and then kept attacking him while he tried to swim to shore, until he drowned. More common though are things like bruises (up to and including black eyes), scratches, and skin-puncturing bites. A google image search for swan attack shows how they don't mess around when they feel threatene (there's even pictures of one attacking a full-grown horse)

Comment Re:What's with turkey anyway (Score 2) 189

It's not all that distant of a relative of chickens, actually - it's in the same family (but a different subfamily). It's kind of wierd that one family (Phasianidae) has almost all of the commonly consumed poultry - chicken, turkey, grouse, quail, pheasant, peafowl, guineafowl, etc. Go up to the order level and you find more (mostly regionally popular) game fowl, like ptarmigan. And once you hit the superorder level, you get the water fowl like ducks, geese, and swans. I can't even think of any other poultry species. There's lots of Aves clades, subclasses, and infraclasses, but apparently the species that people find make good eating are rather clustered together.

Comment Re:Niche energy (Score 1) 90

A lot of companies are involved in a lot of renewables tech research. That doesn't mean that any particular one is going to be profitable. The vast majority are going to be big failures.

Wave power's track record so far has been subpar to say the least. And looking at their diagrams, I can't imagine that they're not headed straight for the same fate. Even if we assume that their numbers aren't overly optimistic, their design looks like it would involve several times more steel per nameplate capacity than a wind turbine tower. And they're operating in a much harsher environment. No rotors, but they're dealing with major hydraulic pumping instead. It just doesn't look like a winner to me.

If it was my job to have a go at wave power, I can't imagine going for anything involving large amounts of structural steel or hydraulic pumping; I'd keep it simple and just go for a grid of cables (potentially a high tensile strength UV-resistant plastic), anchored at the edges to keep tension up across the whole grid, with the only slack available involving the grid pulling on regularly spaced springloaded reels (the rotation thereof generating electricity), with any combination of floats, drag chutes and weighs/anchors to cause the needed tug from the movement of water. No pumps, no hydraulic fluid, no large compressive-loaded structures, just a tensile structure that would be (proportionally) lightweight and easy to deploy.

But hey, it's not my industry ;)

Comment Further on Li, Chan, Norris, etc. (Score 3, Informative) 194

Sorry, didn't quite mean to submit there.

TKD is a very specialized sport art. Very limited engagement rules and a complete lack of tools for dealing with anything but an upright, sparring style opponent relegate it to at best a functional niche limited to kicking (which any well rounded martial artist can convert into a different engagement, ground for instance) in the course of which instantly defanging most of the TKD stylists tools. TL;DR, TKD is more of a sport than a martial art. I should know; I'm dan-ranked in it within the context of the Korean taekwondo jidokwan, one of the earlier kwans that preceded the establishment of the WTF and ITF collaboration / standardizations.

Chan's martial arts background spans several styles (Shaolin gongfu, taekwondo, and hapkido), and consequently is broadly based with ground, standup, upright grappling, locking, striking, blocking, kicking, footwork and defensive components. He is by *any* sane measure a much more well rounded martial artist than Norris (and if you just admire kicking skill, I'm surprised you didn't bring up Bill "superfoot" Wallace.)

Li started training at age 8. He won his first national championship at age 11 -- remember we're talking about China here -- he traveled to more than 45 countries as a member of the Beijing wushu team. He held the title of All-Around National Wushu Champion from 1974 to 1979. He trained in internal and external styles, as well as the (then) required shíba ban bingqi (eighteen arms or weapons.)

(Please excuse the mangled pinyin; I don't use pinyin much, preferring actual hanzi, and traditional hanzi at that. (hanja for you TKD folks.) But slashdot doesn't support them (why? some geek site, lol)

Further, he practices wushu, which looks cool but is not a very effective martial art.

Wushu means "martial art." It doesn't tell you squat about martial art effectiveness, other than that the practitioner, like a "martial artist" in the US, practices some martial art or arts. You should have a look right here so next time you use the term wushu in the context of a Chinese martial artist, you actually know what you're saying. Although, technically speaking, just like gongfu (doesn't really mean martial art at all), the term carries implications you might not initially grasp; for instance, to a Chinese, a Korean TKD master is both a gongfu and a wushu master, plain and simple. Which again demonstrates that wushu doesn't mean anything even close to what you thought it meant.

However, your previous statement is worse in that it amounts to a blanket dismissal of all of China's martial arts, which is nothing short of ludicrous. Combined with your bewilderment of both Chan and Li's training backgrounds, your credibility is somewhere south of zero on this matter.

Comment Expatriate woes (Score 1) 219

I'll breathe a sigh of relief when I have alternative citizenship.

You think? So you haven't had the appropriate discussion with a tax professional familiar with expatriate situations, then. You're in for one seriously depressing conversation. Some locations are worse than others due to local issues in the country of desired residence (the UK is one of these, for instance... your in-country tax load would be very high, starting with VAT and petrol and employment of UK+US tax specialists and going downhill from there -- read this and weep), but you will soon find out just how hard Uncle Sam has worked to make your choice to reside elsewhere a very, very difficult one to follow through on after just a short taste of the many US tax-related downsides, never mind what your ultimate destination country has in store for you.

Comment Re:He still plead guilty to something ... (Score 1) 219

It's not just the chance of long jail terms: benefits of pleading out can include huge financial benefits (trials are extremely expensive), huge time benefits (trials take a long time during which uncertainty and pre-trial restrictions take a very real toll), may pose the difference between not just guilt, but they type of guilt -- felony or misdemeanor, conviction or adjudication withheld, witness activity or fines or restitution instead of part or all of a jail term -- but yes, on top of all that, you know they will throw the book at you if you don't comply with their desire for you to plead out.

The system is, in terms of serving justice, utterly, completely broken by the plea mechanism.

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