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Comment Re:well (Score 1) 61

Technically it is possible to create a system for perfect judgement calls. This law is based around the concept of, 'what the general public feels reasonable', as such to be in affect perfect, it needs to be put to the general public for their opinion. So every right to be forgotten claim, should be put to the public to vote on and when sufficient votes are accrued to remove it, it disappears, this would also take into account contrary votes from members of the public who feel it should remain being deducted from that total. So a reasonably representative number as a percentage of the population, can view the content and the relevant search and vote. Done and finished ;D.

Comment Re:If it's really a policy (Score 1) 147

Sure ban some ads but don't ban others, the ad seemed pretty reasonable and should have been tested upon it's own merits ie a broad range of people of many nationalities with a very broad demographic sharing faith. Jedi was on my census form and will continue to be so for as long as I live (although the appropriateness of the question being questionable and a government official threatening to penalise people if they wrote it it, might have had considerable bearing on that response).

Comment Re:Don't pirate software (Score 2) 66

No matter what is in the video, what makes you think the foolish judge has not turned him into an instant internet hero and made the pigopolists look even worse. Especially to all those views from people who can not speak Czech and just viewed the content to 'argh' support the pirate 239,002 when I added my support. So to be fair what are the latest penalties for abusing DMCA takedown, still fuck all?

Comment Re:Cost of access is key. (Score 1) 311

That was not my point. Ofc we can improve ISP. No idea how much that improves either 'performance' or drops price.

It improves performance a *lot*. As for price, it depends on how expensive that rocket system is. For first stages, an improvement in ISP's effect on the size of the rocket isn't that much greater than linear. But the further up the delta-V chain the engine is used, the more of an impact it has on everything that was used to get it there. An extra hundred sec ISP on a first stage might reduce the system mass by a third; on a second stage up to LEO, maybe cut it in half; on a kick stage for a Mars transfer orbit, maybe cut it by two thirds. On an ascent stage from the surface of Mars... well you get the idea. Shrinking down a rocket to a small fraction of its size - fuel, tankage, and engines - well, that's really significant. ISP is very, very important for upper stages. So you can afford to pay quite a bit for those top stages if it improves their performance. Just not an "unlimited" amount.

There is no way a high tech electrical engine will improve its performance by 10% regardless how much money or time you put into it: the efficiency is already between 98.5% - 99.5%, up to 99.9% in some cases.

This is getting a bit offtopic, but at least the electric engines in EVs don't usually run at nearly that high. Depending on the type they might average 85 to 94% on average. It varies over their load cycle.

Regarding rockets: there is simply not much margin anymore in changing the form of the exhaust tube, burn chamber etc

Actually you can. The general principles of how rocket engines work are fixed, of course - your exhaust will never exceed its local speed of sound in the throat, and then you want to expand it as close to ambient pressure as you want. But the details vary greatly. There's bell nozzles, linear nozzles, annular nozzles, aerospikes, throatless nozzles, atmospheric wake compression, and on and on. There's tons of different ways - developed, in development, and in theory - to pump and inject your propellants - where they need to be pumped at all. Even many propellants that are traditionally thought of as being in one state can be implemented in other states. There's various ways - developed, in development, and in theory - to prevent nozzle erosion. To improve regeneration. To reduce mass. And on and on and on. Rocket combustion is a rather complex thing and we're still trying to get a handle on it. Do you know that we still really don't know how aluminum burns in solid rocket propellant? There's something like five different competing theories. I mean, things like this are a Big Freaking Deal(TM), especially when such small improvements in upper stage ISP have such significance for lower stage mass. And even on your lower stages there's a lot of things that have a big effect on your system cost. For example, how to stop resonant shocks from ripping them up - a lot of people don't realize that one of the main benefits of adding aluminum first stage to propellant mixes is that the droplets of burning aluminum damp shocks. (yeah, it increases ISP too by raising the exhaust temperature, but it also has disadvantages, such as not contributing to expansion, slowing down gases (particularly near the nozzle), and impacting/eroding the throat (or even forming an accumulating slag)

Re, nuclear+chemical. There are proposals for this. The main issue isn't efficiency - the extra chemical energy doesn't make that much of a difference - but thrust. The downside to nuclear thermal is that the reactor is so heavy (fission is like that, unfortunately) that the mass ratio is only something like 3-4:1. That's really bad (you generally get 15-20:1 or even better for a chemical first stage). So the approach is to inject oxygen early in the ascent phase for added thrust, but only run on hydrogen higher up when gravity losses are lower. I'm really not that sanguine about nuclear thermal rockets getting a serious development program any time soon, though. The public overestimates the risk, of course - not only am I sure they'd well seal the fuel elements against whatever damage would be incurred by explosion or reentry, but there's the simple fact that the fuel is "fresh", not contaminated with the more hazardous actinides. But it's going to be a hard sell. And a really hard development project, if they ever did try again. Gigawatt-scale flying nuclear reactors that pose radiation hazards during assembly and test aren't exactly childs' play.

Comment Re:Putin cares! (Score 1) 32

So explain to everyone why exactly you want to keep your medical records abroad?
Why do you want your dental records abroad?
Why do you want you local investment details abroad?
Why do you want you correspondence with local relatives, neighbours and friends abroad?
Why do you want correspondence with your local employer abroad?
Why do you want you dealing with local government abroad?
Why do you want your dealings with State government abroad?
Why do you want your dealings with federal government abroad?
Why do you want your dealings with local retailers abroad?
Seriously why the fuck would you want the contents of your own hard disk drive, at your own desk, stored abroad?

The list goes on, phone communications, what you watch on smart TV, fucking conversations in your own fucking lounge room, stored abroad. Me thinks your a full of PR=B$. I side with those who support the idea, that any data about me created in my country, stays in my country and that it be regularly audited by the government for invasions of privacy and excessive data retention. Don't trust my government, well, I trust corporations a whole lot less and demand that my government keep a bloody close eye on their activities and start fining them sufficiently that egregious corporations are actually sent into bankruptcy and their executives imprisoned.

Comment Re:The guy aint no Sagan... (Score 1) 311

You forgot to exclude operational expenses.

Yes, people to run robots and comm time on the DSN. We're not talking about massive expenses here. The real expenses are the capital costs.

And also didn't mention that you can't just lob chunks of metal straight to Earth's surface,

Actually, you really just can. Even random rocks from space - not shaped for optimal entry shape, not cemented together by anything yet what nature chose to gie them - do this all the time. They have to be between a certain size range (too little and the whole thing ablates; too large and it explodes, either in the atmosphere or on impact), but the random creations of nature do it; delberately shaped and sintered projectiles should have no trouble with it, with (proportional to their mass) relatively little burnoff.

You would, of course, need a rather large area designated as the impact area; even with very precise aiming, by the time they get to Earth and undergo reentry the random variables will spread them out over a sizeable chunk of land. A large salar might be ideal, since they get resurfaced periodically so the impacts wouldn't be damaging the landscape.

By your same logic, the mining of minerals on Earth would be zero dollars per gram if the equipment was solar powered and automated

It's almost as if I didn't discuss capital and ongoing costs in my above post.

Launch costs really are key to the rate of development at the very least, in that they limit the rate in which funding can be raised for the necessary exploratory and test craft to be launched. Even if the economics for operating a mine on a NEO works out really well at present launch costs, you have to prove that you can do it before you can raise the billions to build it. And to prove that you can do it you have to launch a number of missions while you're still relatively poorly funded. They face the same problem that Bigelow has faced - a probably reasonable business plan but the early phases hinging around factors that they don't control.

It does nobody any good to pretend that the lack of a space economy is because investors are cowards and morons

I think you need to go back and read my last post again, particularly all of the "it's too early to say"/""we don't know"/"but time will tell"/etc lines. I'm not saying that at all. I'm saying that there very well could be a compelling case for asteroid mining even without any radical changes in space technologies. But there's a great deal of work to prove that before we can get to that point.

Comment Re:Wut? (Score 1) 91

How can a bunch of cabbies all be running under the same banner if there isn't one?

To be able to pick up passengers by hailing, use taxi ranks and taxi lanes, a license is regarded from the local council. The council sets the rules, and that includes things like the knowledge, turning radius of vehicles, disabled access, rate per mile, and so on and so forth.

Comment Re:Duh (Score 1) 647

Cases get logged they get fixed.

You missed the part where Lennart cheerfully refused to fix it.

That takes time and all software is vulnerable to being tricked into failing to boot properly.

Are you deliberately trying to misrepresent the arguments here? No one's saying it should have booted successfully. What me and the other guy are saying is unchecked segfaults are bad and should be fixed. Unlike Lennart's claim this is demonstrably not a problem which only affects old kernels. It affects new ones, and missing checks and refusing to fix them is just poor practice.

Seriously, why do people come up with the most lame defenses of systemd? People would rip MS a new one if such a piece of code was found in Windows.

Comment A field full of two layers of firefighters. (Score 1) 98

As mentioned previously, my mental model of semiconductors and the like is a fireman's water brigade, were either the majority of the line has buckets or empty hands.

It helps if, instead of a line, you think of a LOT them standing in a two-D array (like in the yard of the burning building, or a section of a parade that's stopped to do a little demo). It's really three-D, but we'll want to use up/down for something else in a bit...

For metallic electron conduction everybody has TWO buckets, one for each hand, and when a guy by the fire throws a buck of water on it (bucket and all) on the fire, a guy farther back immediately tosses him a bucket, the guy behind him essentially instantly throws HIM a bucket, andso on. Hands are effectively never empty.

For semiconductors, imagine two layers of these guys, the second standing on the firsts' shoulders or on a scaffold right above them, and about enough buckets for each of the guys on the ground to have two and the guys on the scaffold to have none. (There's actually many layers of scaffold, but the rest are so far up that it's hard to get a bucket to them, so they mostly just stand around.)

Usually nothing useful is happening. Everybody on the bottom layer has both hands full of buckets, and it's hard to hand a bucket up to the guys on the top.
  - Electron-hole pair creation: Somebody comes up with the energy to heave a bucket up to the guys on the upper layer, leaving a guy with one hand empty in the lower layer. (Maybe somebody (a photon, for instance) comes along with a lacrosse stick and whacks a bucket up to a guy in the top row - dying or becoming exhausted and much weaker from the effort.) Now you've got one guy with a free hand in the lower layer (a hole) and one bucket on the top layer (a free electron).
  - Electron conduction in a semiconductor is that bucket on the upper layer. The guys there can hand it around easily, or toss it along a diagonal until it would hit a guy - who catches it. They're all standing on accurately-spaced platforms so the bucket can go quite a way before somebody has to catch it. Suppose there's a slope to the yard, with the fire at the bottom. Then, if tossed too far, the bucket might pick up substantial speed and knock the guy who catches it out of place (electromigration), or fall down to the lower layer and knock another bucket out of somebody's hand and bounce, ending up with TWO buckets on the upper layer and an empty hand below (avalanche electron-hole creation).
  - Hole conduction is when you've got an empty hand on the bottom layer: Now it's easy for a guy with two buckets to hand a bucket to a guy with only one, exchanging a bucket for an empty hand. But now the guy whose hand had been empty has two buckets and nobody in the downhill/toward-fire direction to hand a bucket to, while the guy who handed it off has an empty hand and can grab a bucket from somebody farther uphill / closer to the water source - or beside him, or diagonally. So "empty-handedness" (a hole) can move around as a persistent entity while the individual buckets gradually work their way in the general direction of the fire, only making a bit of progress "when a hole comes by". Though the water makes progress toward the fire, the action is all where the holes are making progress away from the fire.
  - Electron-hole annihilation: Somebody has a bucket on the upper layer when a guy below him has an empty hand. So he drops the bucket. CLANG! Ouch! Now there's no "free bucket" on the upper layer, no free hand on the lower layer, and the energy of their separation went somewhere else (knocking the guy sideways so he bumps into his neighbor and generally making the guys vibrate, "creating a guy with a lacrosse stick who runs off to whack at buckets", etc.)
  - P-type doping: A guy in the bottom layer had a sore hand and only brought one bucket to the fire, thus having a free hand from the start. He can take a bucket when a neighbor pushes it at him (the hole moves away). But he'd like to hand it off and have his sore hand free again (so holes tend to stick around at his site). It's lots easier to "make a free hole" by convincing him to hold a bucket in his sore hand than by tossing a bucket up to the guys on the scaffold, but does take a little effort.
  - N-type doping: One of the guys on the upper level really likes to hold a bucket, so he brought one with him. The guy next to him can grab it from him, but if another comes along he'll try to hold on to it a bit until somebody shames him into letting go again or wrestles it from him. It's lots easier to get him to let you use his bucket for a while than to pull one up from the guys on the ground, but it does take a little effort.
  - Tunneling through a potential barrier: There's a ridge across the field. It's hard to hand buckets up to the guys on the ridge, so they don't flow across it very well (unless someone at the side of the field is pushing the buckets really hard...) Occasionally the guys on one side of the ridge hand a bucket through the legs of the guys standing on the ridge to the guys on the other side.
And so on. B-)

I'm keenly interested in finding more material to read up on the observed Hall effect measurements. Thanks again for your contribution to the discussion.

The wikipedia article on the hall effect has a section on the hall effect in semiconductors, but both it and the reference it uses start from treating the hole as a charge carrier with a fixed charge and a mobility different from a free electron, and just computes formulai from there.

If the hall effect on hole currents were fallout from the hall effect on the individual electron bucket-transfers, rather than the hole acting like a positive charge carrier in its own right, you'd think it would go the other way

Comment Re:Duh (Score 1) 647

That sounds more like a kernel problem.

No, it was a failure to mount the cgroups virtual filesystem. The kernel has cgroups, but the VM was not set up to have access.

You make a config error you get a boot problem. Systemd doesn't know what you are did. Change the config outside the VM and try again. How is that any different than throwing an error?

Are you honestly saying there's no difference between throwing an error with proper logging, sensible message, error handling and etc and dereferencing a null pointer and segfaulting?

With friends like you, systemd barely needs enemies!

Comment Just another example of useless insurance (Score 1) 100

How much do you think Cox has been paying their insurer? How long has Cox been paying their insurer?

Now when they need it, the insurer gives them the big middle finger.

Just goes to show what a scam insurance is. You pay, and pay, and pay, and pay, all for nothing.

Cox would have been better off keeping the money they paid for insurance. At lest then they would have gotten some use from it.

Chemist who falls in acid will be tripping for weeks.