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Comment Re:You better fix your unicode characters (Score 1) 14

Just because Trump attends a Presbyterian church doesn't make him Christian, it makes him a wolf in sheep's clothing. Trump worships only two things: Himself, and the ancient Greek god Plutus.

I hate it when someone who seems to always go against Jesus' teachings claims to be a Christian.

That goes for all the Republicans, with the possible exception of Carson and perhaps Rubio. Actually I have my doubts about almost all politicians. You know what Christ said about lawyers and the rich, which almost all of the Senators, Congresspeople, Governors, and President.

The optimal answer is for politics to avoid setting itself in conflict with faith, and there are reasonable compromises to achieve this.

Agreed. Remember the three in the furnace who were to be burned alive for refusing to follow the law and bow to the idol. I'm not Hindu, but I would be aghast if they passed a law making it mandatory to eat beef every Saturday.

As to the unicode, that's slashdot's fuckup.

Comment Re:Hillary has... been opposed to single payer (Score 1) 25

You are pants are on fire?

IMO any of the three Democrats would be a better President than any of the Republicans, although there are two or three Republicans that might not fuck up America too badly.

Perhaps the conspiracy was cooked up by her supporters? The insurance companies are the major reason health care is so expensive and ineffective here.

I'm disgusted by the Republican candidates' cowardice and heartlessness when it comes to refugees, and the fact that none have served in the military but are all for going to war. Back in the Vietnam war days those sorts were called "chicken hawks", and you'll find few veterans who can stomach them.

Unless you're rich and white you'd be a fool to vote for any of them.

Comment Re:Oh, really? (Score 1) 186

Samsung has sold hundreds of millions of phones with OLED screens in.

Samsung manufactures OLED screens. They don't have to worry about a supplier not being able to meet demand, because they are the supplier. If they have to throw more money at it to bump up production, they will. If the yield is too low, they can make up for it by cranking up the price of OLEDs disproportionately for everyone else that they supply panels to, or by cutting off those other companies entirely.

A company buying panels from somebody else doesn't have that flexibility.

Comment Re:Or just make the diesels hybrids (Score 2) 164

And even the best public transport system generally isnt going to start and stop *exactly* where you need it, so there still is going to be *some* walking. Which some people with disabilities or health problems simply can't manage. And to achieve a good public transport system - with frequent stops, densely placed stops, relatively direct routes and affordable prices - is entirely dependent on population density far more than it is on "will". In places with high density, it's a relatively straightforward process to have a good public transport system. In places with moderate to low density, it can be difficult to nearly impossible. And weaknesses in public transport system are a viscious cycle: the less frequent the stops, the further spaced out they are, the longer the transit times, and the more expensive the rides - the fewer people will ride them. The fewer that ride the less frequent you have to have the stops, the further apart they need to be, the less direct the routes, and the less affordable the prices.

Comment Re:Cost of access is key. (Score 1) 329

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:The guy aint no Sagan... (Score 1) 329

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: Easy solution (Score 1) 455

Eventually, those bearings fail, and you have to replace the motor, but not for a very long time.

I certainly hope not. You can typically press new bearings in for just about all other motors, after all.

You can put new bands in a transmission, too. Still, probably 99% of the time, you get a rebuilt transmission installed, and the installer ships back the old part to be remanufactured. I would expect that to be true for electric motor repairs as well.

You missed suspension, steering, body work/subframe rot, electical issues, HVAC issues, LED lights (yeah, they do go bad, apparently rather often from what I've seen on the road), tires, snow tires and wheels, parking brake adjustment, brake fluid, bearing replacement, differential work (though that could be eliminated), axle issues, interior problems (broken seats, for example), interior lights, batteries, and probably other stuff I've forgotten.

Brakes and steering on most electric vehicles are electrical, not hydraulic, which should result in very low maintenance, at least within the currently typical lifespan of a car.

Besides, most of the things on that list are repairs (after failures), not routine maintenance (to prevent future failures). There's nothing you can do maintenance-wise to prevent a blown interior bulb or a broken seat (except perhaps losing weight if you're on the heavy side).

The only thing on your list that I would consider true maintenance is tires, which was one of the things I mentioned.

Comment Re:seriously? (Score 1) 82

Are the other variants more dialectal? In addition to huoji ( / ) (fire chicken) what I read states that there's also qimianniao ( / ) (seven-faced bird), tujinji ( / ) (cough up a brocade chicken) and tushouji ( / ) (cough up a ribbon chicken)

(hope Slashdot doesn't mess up the characters)

Comment Re:seriously? (Score 1) 82

On the other hand I would want to talk to Archimedes

You speak ancient Greek and can communicate with the dead? Okay, I'm impressed. ;)

Thanksgiving trivia for the day: the word for "turkey" comes from extensive and long-running confusion about where the bird came from. For example, in English it's called Turkey. In Turkey it's called "hindi", referring to India. In India it's called Peru. In Peru it's called "pavo", referring to peacocks, which are native to south and southeast asia, such as India (cyclic there), Cambodia, Malaysia, etc. In Cambodia (Khmer) it's called "moan barang", meaning "French chicken", while in Malaysia it's referred to as "ayam belanda", meaning "Dutch chicken". Both of those in turn think it comes from India: in French it's called "dinde" (from "poulet d’Inde", aka "chicken of India"), while in Dutch it's "kalkoen", referring to a place in India. Greek has a number of local dialectal names, such as misírka, meaning "egyptian bird", while in Egypt it's called dk rm, meaning the Greek bird (even though the latter part of the name derives from Rome - the Italians, by the way, thinking it comes from India). One variant of Arabic even credits it to Ethiopia.

A couple languages deserve special credit for their words:

Best accuracy: Miami indian - nalaaohki pileewa, meaning "native fowl"
Worst accuracy: A tie between Albanian (gjel deti, "sea rooster"); Tamil (vaan kozhi, "sky chicken"); and Swahili (bata mzinga, "the great duck")
Most creative: Mandarin - many names with meanings such as "cough up a ribbon chicken" and "seven-faced bird"
Least creative: Blackfoot: ómahksipi'kssíí, meaning "big bird". Hmm...

We all agree on the necessity of compromise. We just can't agree on when it's necessary to compromise. -- Larry Wall