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'Thermoelectrics' Could One Day Power Cars

dbIII Re:I hate personal definitions (166 comments)

More than 10m/s expansion so explosion by your pet definition isn't it? I also suggest your read the wikipedia link you sent to me.

yesterday
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'Thermoelectrics' Could One Day Power Cars

dbIII Re:A bit too insulting keyboard jockey (166 comments)

I'm sorry I was so blunt but your "correction" of my description of diesel was a bit annoying and appeared to both ignorant and patronising as such cut and pastes with understanding often do on the net.

The main downside of using explosives as a fuel at this point is that coal, oil, gas etc are very cheap and the energy cost of turning them into other stuff that explodes is higher than the energy you get out of the explosions. With nearly free electricity you can get nearly free hydrogen so the game changes, but until then it's the same dream from the time of Nobel that isn't much getting closer. As for transport the downside of explosives is you have all that oxygen in the tank, while with combustion the idea is to only carry half of an explosive.
IMHO the difference between a fuel air explosive and a diesel cylinder is scale. The term for a little explosion may be deflagration, but that's just describing the scale below an arbitrary cut-off point. Physically, chemically and mechanically the same thing is going on.
At least now think I get what you are going on about - rocket motors pushing liquid metal around? The very dense threw me initially and made me think you were referring to some sort of solid heavy metals - for instance lead flows really well at high pressures not far above room temperature, but not well enough to last long so a full liquid like you suggest makes more sense. If that's what you mean there are a few interesting challenges but at least some are being actively worked on (the nuclear industry is busy trying to solve some liquid metal problems, mostly in Russia and India).

yesterday
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'Thermoelectrics' Could One Day Power Cars

dbIII Re:I hate personal definitions (166 comments)

I was apparently mistaken about there not having ever been a PDE powered flight

From France to London in the mid 1940s - get a grip before trying to lecture others who are not entirely keyboard jockeys.

yesterday
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MIT Designs Tsunami Proof Floating Nuclear Reactor

dbIII It became a magnet for the greedy (206 comments)

There was enough money involved to attract management with plenty of political skill to get the good jobs but no background on what they are attempting to manage. That has led to a cycle of needing a unmistakable disaster with each generation of management or they forget their responsibilities. TMI was the perfect one since it was an obvious fuckup with little consequence, but it was too long ago for anyone other than engineers, technicians and other non-horse judges to take seriously. Chenobyl gets written off as "those crazy commies". The most recent chain of stupidity is unfortunately being written off as entirely due to the tsunami and the similarities to US reactors and US industry practices are being ignored.

As for waste storage - any mention of it was seen as being some sort of traitorous move against the nuclear industry, which is why the Synroc I saw in 1987 didn't get the funding and approval to be properly tested until a couple of years ago. Waste storage has been so badly managed that there have been incidents such as one where some idiots put enough drums of high level waste together to get something similar to the Chicago atomic pile.

yesterday
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MIT Designs Tsunami Proof Floating Nuclear Reactor

dbIII Re:Why? (206 comments)

What happened to the IFR is a very good example of the US nuclear industry eating it's own children and why you are not going to get anything as good as it without buying it from India or cleaning up government corruption.

yesterday
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MIT Designs Tsunami Proof Floating Nuclear Reactor

dbIII Safe behind the deepwater horizon? (206 comments)

Another option to not run out of water is to just have the thing downhill from a large permanent lake.
Putting something out at sea and sacrificing containment for the sake of reliable cooling water seems to be ignoring that there is more than one possible mode of failure. It also means that the thing can never be mothballed but instead needs to be actively dismantled at the end of it's life - not a trivial task when there would be a great deal of radiation involved in many parts being demolished.
However what this thing DOES have going for it is a small reactor size which brings it in from being an utterly stupid suggestion to something that may just work if as much care is taken as is with the small military reactors - which probably removes it from commercial consideration without a few "shortcuts". IMHO the same small reactors on land with reliable cooling water are a far more sane idea.

yesterday
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'Thermoelectrics' Could One Day Power Cars

dbIII A bit too insulting keyboard jockey (166 comments)

Hey - IT dude - I first saw a working scramjet model in 1986 when I was learning how to be an engineer so don't need some lecture from you about that or some condescending shit about how I should learn about diesel engines (arbitrary definition shift at 100m/s) from someone who doesn't know about them himself or some stuff about people in very early stages of attempting to revive the V1 engine (fair enough, but stating it as if it's viable now - that is insulting the intelligence of yourself and the readers here).

Nitro is cheap as hell to make and releases incredible power

The world has moved on to better things that are a hell of a lot cheaper per watt (even ANFO needs too much energy input to be considered for routine use as a fuel), and for transport it would suck because it's extra weight for the same sort of energy density you get from something that you add available oxygen to. In the 1930s there was a lot of speculation about running aircraft engines on explosives which went as far as rocket planes and no more because of all that extra mass of fuel - the jet engine mostly killed off that idea apart from really fast planes, it's just not practical to take that extra weight unless you are in a huge hurry. The idea of a scramjet is like a rocket that needs less fuel since it can compress enough oxygen to burn out of the air - going back to a V1 style pulse jet is a step backwards since it means carrying a lot more fuel for little or no gain.

very dense inert metallic alloy as a hydraulic fluid

That's a bit too much. Are you deliberately pulling my leg here to make fun of me or are you just using real words as technobabble you do not understand to attempt to convey some other meaning about a molten tungsten mixture or something?

yesterday
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'Thermoelectrics' Could One Day Power Cars

dbIII I hate personal definitions (166 comments)

Ah, I see now. Differing definitions of what ignition under pressure and how the resulting sudden gas expansion is described. Where do the larger explosions such as sometimes occurs in the F1 engine in the Saturn V fit in your definition - are they also not explosions or is your line drawn somewhere between the two? Are you someone with the 1930s gunpowder engine idea or is it coming from somewhere else that actually considers that carrying around an oxidiser when you do not need to is a drawback?
To sum up - when you "correct" somebody it's best to consider which parts of your correction are based on your own gut feelings and which are more easily communicated. I'm intrigued by your explosion powered engine idea but suspect it's the same drivel dreamed up by people without a grasp on the topic that are missing a major flaw - if not please feel free to tell us exactly why they will "replace scramjets" - which as you should know are only there to replace rockets because they can save the weight of an oxidiser (so your explosive powered system sounds a bit like a step backwards).

yesterday
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'Thermoelectrics' Could One Day Power Cars

dbIII Re:Cheap Solar Power (166 comments)

Because the photoelectric effect moves a lot of electrons around while the thermoelectric effect doesn't move as many around for the same input from sunlight. The very expensive type of photovoltaic cells are used with lenses in some applications.

2 days ago
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'Thermoelectrics' Could One Day Power Cars

dbIII Let me give an example of "might" (166 comments)

Back a few years there was a quest for an all ceramic car engine. Fuel could burn a lot hotter so your could get a lot more power per litre. It seemed obvious. A few partial successes happened and then Mercedes actually built one. On a test bed the performance was wonderful. In a car the extra weight required to keep it cool made the performance of a 1936 Chevy look better. In the end some ceramic parts are in use, mostly in trucks, but making it all ceramic to get those higher temperatures is impractical in something that has to move it's own weight around.
So it all comes down to physical contraints instead of yelling OMG flying car! Please forgive us for not being instant fanboys until we know something about what is going to distinguish this thing from reverse peltier effect devices we already know about. The thing has got to be able to add more performance than it reduces by weight for it to be worth it.

2 days ago
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'Thermoelectrics' Could One Day Power Cars

dbIII Re:power cars? technically no (166 comments)

Am I missing something here or are you ignoring how diesel engines work? To me at least it looks like a series of small explosions.

2 days ago
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'Thermoelectrics' Could One Day Power Cars

dbIII Re:power cars? technically no (166 comments)

I suppose so but that sounds very impractical since a bunch of candles would give you a larger heat difference. However I don't think many would call it a thermoelectric car just as a diesel-electric train is not called electric and a Prius is not called electric. It's probably best to accept that some people won't accept your proposed terminology and move on to discuss more than just semantics.

2 days ago
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Survey: 56 Percent of US Developers Expect To Become Millionaires

dbIII Re:wait, what? (453 comments)

such as rapidly changing design specifications in a mass production line

That's always available and at a cheaper cost when you actually own the mass production line. Of course you need some sort of volume to justify production yourself instead of paying someone else to do it and you need to employ engineers for longer than it takes for the first setup of the line which is why such a thing is very unpopular in the USA.

A move towards the short term and cutting things with long term benefits made local manufacturing inflexible. Meanwhile the Chinese are still copying the successful US businesses of the 1960s so are still flexible.
If they hit the "just change the appearance every year and it will sell - sack those engineers we don't need them anymore" attitude of a great deal of US manufacturing management then there will be no benefit to outsourcing. However, if the trend continues, by then they will own the market and there won't be US money available to pay the Chinese to make stuff.

I agree, outsourcing is good if you want something done you can't do in-house, but I wanted to point out why I think it's not being done locally and how I think some places that have outsourced their core business are doomed.

2 days ago
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GoPro Project Claims Technology Is Making People Lose Empathy For Homeless

dbIII Re:perception (318 comments)

Large numbers of homeless people are symbolic of a failure somewhere - shantytowns may be a symptom of trying to deal with it instead of hiding that there is a problem by moving people along.

2 days ago
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GoPro Project Claims Technology Is Making People Lose Empathy For Homeless

dbIII Obviously (318 comments)

You don't have money to do much for the homeless and neither do I. However we both pay taxes to people with the resources to deal with the problem in bulk.

2 days ago
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GoPro Project Claims Technology Is Making People Lose Empathy For Homeless

dbIII What empathy do they have anyway? (318 comments)

Considering nearly all of what Americans call Christianity has purged "the good samaritan" from what they teach and instead taken a "if you have money it proves you deserve the love of Jesus" approach then what empathy was there for the poor in the first place?
Also people just cannot see themselves falling into that position so they blame the victims. The attitudes to and of the Katrina refugees pointed that out very well - we had "pious" people like Barbara Bush saying that people who were homeless before Katrina should not be helped and we had people that suddenly found themselves becoming the "worthless homeless person" they never imagined they would be and having to rely on charity, even if it was only for a short time.
Another way to look at it is at this time any homeless person in the USA has a more positive financial balance sheet than Donald Trump. He defaulted on a couple of vast fortunes in debt and comes nowhere near matching them since, but his connections allow him to be respected instead of despised like the homeless people that also ran out of money.

2 days ago
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Vintage 1960s Era Film Shows IRS Defending Its Use of Computers

dbIII People hate to see government spending money (145 comments)

People hate to see the government spending money on new technology which is why so many places have software and hardware that would have been retired in a commercial environment a decade earlier.

2 days ago
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UN: Renewables, Nuclear Must Triple To Save Climate

dbIII Re:Apply critical thinking instead of changing top (429 comments)

Oh yeah, if anybody is pro nuclear must be either misguided or a paid propagandist

I didn't say anything about nuclear one way or another which is why I'm calling your distraction and accusations childish.

but I would call myself a scientist

Oh FFS. Act your age.

2 days ago
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How 'DevOps' Is Killing the Developer

dbIII Different mindsets required (223 comments)

New code is not perfect on creation and developers need to be prepared to swing the axe, scrap stuff that doesn't work and start off different approaches.
However in production it's better to make very gentle changes to a unstable house of cards even if it is utter shit held together by chewing gum and string.
To work in both you need to be able to switch between mindsets because they are really very different jobs. Someone working in both is not ideal. Even if you are very good at both there is a strong temptation to make radical changes, make incremental changes an place them in production and thus limit options in development or to develop something new that incorporates the flaws of something in production. An ideal is good communication between people in both roles.
"Switching hats" can result in too many compromises and being either too conservative or too radical for the project. If you are stuck in that situation external input from testers or somewhere is vital as a sanity check.

2 days ago

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