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Comment Another useful vacuum tube: Thermionic converter. (Score 1) 94

Another vacuum tube technology with current applications and substantial advantages over semiconductor approaches to the same problems is the Thermionic Converter. This is a vacuum-tube technology heat engine that turns temperature differences into electric power - by boiling electrons off a hot electrode and collecting them, at a somewhat more negative voltage (like 0.5 to 1 volt), at a cooler electrode.

Semiconductor approaches such as the Peltier Cell tend to be limited in operating temperature due to the materials involved, and lose a major fraction of the available power to non-power-producing heat conduction from the hot to the cold side of the device. Thermionic converters, by contrast are vacuum devices, and inherently insulating (with the heat conducted almost entirely by the working electrons, where it is doing the generation, or parasitic infrared radiation, which can be reflected rater than absorbed at the cold side.) They work very well at temperatures of a couple thousand degrees, a good match to combustion, point-focused solar, and nuclear thermal sources.

Thermionic converters have been the subject to recent improvements, such as graphine electrodes. The power density limitation of space charge has been solved, by using a "control grid" to encourage to charge to move along from the emitter to the collector and magnetic fields to guide it (so it doesn't discharge the control grid and waste the power used to charge it).

Current thermionic technology can convert better than 30% of the available thermal energy to electrical power and achieves power densities in the ballpark of a kilowatt per 100 square cm (i.e. a disk about 4 1/2 inches in diameter). That's a reasonably respectable carnot engine. This makes it very useful for things like topping cycles in steam plants: You run it with the flame against the hot side so it is at the combustion temperature, and the "cold" side at the temperature of the superheated steam for your steam cycle. Rather than wasting the energy of that temperature drop (as you would with a pure steam cycle) you collect about a third of it as electricity.

It also beats the efficiency of currently available solar cell technology (and the 33.4% Shockleyâ"Queisser theoretical limit for single-junction cells), if you don't mind mounting it on a sun-tracker. Not only that, but you can capture the "waste heat" at a useful temperature without substantial impairment to the electrical generation or heat collection, and thus use the same surface area for both generation and solar heating. (Doing this with semiconductor solar cells doesn't work well, because they become far less efficient when running a couple tens of degrees above room temparature.)

Comment Re:Many a young engineer.... (Score 2) 94

... every schematic drawn by every semiconductor engineer got the arrow backwards.

As I heard it, The arrow is "backward" because Benjamin Franklin, when doing his work unifying "vitreous" and "resinous" electricity as surplus and deficit of a single charge carrier (and identifying the "electrical pressure" later named "voltage"), took a guess at which corresponded to a surplus of a movable charge carrier. He had a 50% chance to assign "positive" to the TYPICAL moving charge carrier in the situations being experimented with (charge transfer by friction between different substances, currents in metallic conductors, and high voltage discharges in air and water-in-air aerosols) and happened to guess "wrong".

Thus we say electrons have a negative charge, "classical current" corresponds to the sum of the flow of moving positive charge minus the flow of negative charge (i.e. the negative of the electron current, which is all there is in normal-matter metallic conductors), the arrowhead on diodes (and junction transistors) points in the direction of classical current across a junction, and so on.

But though it's the charge carrier in metallic conduction and (hard) vacuum tubes, the electron ISN'T the only charge carrier. Even in the above list of phenomena, positive ion flow is a substantial part of electrical discharge currents in air - static sparks and lightning. Positive moving charge carriers are substantial contributors to current as you get to other plasma phenomena and technologies - gas-filled "vacuum" tubes (such as thyratons), gas an LIQUID filled "vacuum" tubes (ignatrons), gas discharge lighting, arc lighting, arc welding, prototype nuclear fusion reactors, ...

Move on to electrochemistry and ALL the charge carriers are ions - atoms or molecular groups with an unequal electron and proton count, and thus a net charge - which may be either positive or negative (and you're usually working wit a mix of both).

And then there's semiconductors, where you have both electrons and "holes" participating in metallic conduction. Yes, you can argue that hole propagation is actually electron movement. But holes act like a coherent physical entity in SO many ways that it's easier to treat them as charge carriers in their own right, with their own properties, than to drill down to the electron hops that underlie them. For starters, they're the only entity in "hole current" that maintains a long-term association with the movement of a bit of charge - any given electron is only involved in a single hop, while the hole exists from its creation (by an electron being ejected from a place in the semiconductor that an electron should be, by doping or excitation, leaving a hole) to their destruction (by a free electron falling into them and releasing the energy of electron-hole-pair separation). They move around - like a charge carrier with a very short (like usually just to the next atom of the solid material) mean free path.

For me the big tell is that they participate in the Hall Effect just as if they were a positive charge carrier being deflected by a magnetic field. The hall voltage tells you the difference between the fraction of the current carried by electrons excited into a conduction band and that carried by holes - whether you think of them as actual moving positive charge carriers or a coordinated hopping phenomenon among electrons that are still in a lower energy state. Further, much of interesting semiconductor behavior is mediated by whether electrons or holes are the "majority carrier" in a given region - exactly what the hall effect tells you about it.

So, as with many engineering phenomena, the sign for charge and current is arbitrary, and there are both real and virtual current carriers with positive charge. Saying "they got it wrong" when classical current is the reverse of electron current is just metallic/thermionic conduction chauvinism. B

Comment Re:Vacuum tubes handle EMP's better (Score 1) 94

"No point progressing since the bombs are gonna fall any day now. Then where will your fancy silicon highways and databases be?"

Given that the Internet Protocol and much of the rest of the networking technology that still underpins the Internet were developed as part of a cold-war program to create a communication system that could survive a nuclear attack that destroyed most of it, and still reorganize itself to pass messages quickly, efficiently, and automatically among any nodes that still had SOME path between them, your post seems to come from some alternate universe to the one I inhabit.

Comment Who knows? (Score 1) 20

There are too many variables to predict one way or another.

People making minimum wage who get raises usually don't spend the extra money on more stuff. They try to pay their bills on time. Or purchase the same essential items, but at a slightly higher quality.

That is, steak one day a week instead of hamburger. That doesn't necessarily increase any jobs anywhere at all.

It is also possible they buy more stuff, but where are the extra (if any) jobs created? If they're buying cheap crap imported from China, are the extra jobs made in China?

If they buy extra fast food, that probably won't lead to more jobs as very few of those places are working at capacity to begin with so won't need to hire more to accommodate a small increase in volume. It can be absorbed by the current workforce.

More and more fast food places are automating as opposed hiring more workers. They're getting drink robots, fry robots, ordering kiosks, etc.

This is the equivalent of the Republican "if you lower the State taxes, business will increase and more jobs will be created".

Yes, that will happen, if and only if, taxes are the largest impediment to business in a State and all the other basic needs are met. By other needs I mean infrastructure, qualified workforce, etc.

In most cases, as the State of Kansas is finding out the hard way, taxes aren't the big reason business isn't moving there. There are several other factors that need to come into play. And by cutting the taxes too much, they lost the revenue needed to pay for the infrastructure and educational institutions needed to also attract and support businesses.

In short, it MIGHT work but there are so many other variables in play that there is no way to tell.

Comment Re:Government interference with markets (Score 1) 20

Good. We absolutely do not want many of the natural outcomes, such as company towns, 18-hour work days and enslaving wage levels.

The natural, unregulated market leads to a power imbalance that only grows greater as the company increases in size.

By "we", I mean society. Government regulation is almost reactionary. That is they react after the system gets too far outside acceptable bounds. We started this country with minimal government intervention in the markets and have steadily increased as the shit hits the fan from time to time.

Sometimes they go to far, sometimes not far enough -- but to your statement of "...having government tamper with the market always leads to perverse outcomes, always" I say "good".

Comment The IRS keeps its hooks in US citizens who leave. (Score 2) 359

I'd also move my operation to Ireland if I could.

What's stopping you?

The US tax code. The US keeps its hooks in its citizens and companies, for decades, if they try to leave, even if they move out and renounce their citizenship.

The US does this to a far greater extent than other countries who generally don't tax their citizens if they're out of the country for more than half a year. (This is where "The Jet Set" came from: Citizens of various non-US countries who had found a way to earn a living that let them split their time among three or more countries every year and avoid enough income tax to live high-on-the-hog, even on an income that otherwise might be middle-class.)

Only really big companies, with armies of lawyers, can find loopholes that let them effectively move out of the US to a lower-taxing alternative. You'll note that TFA is a lament about how one managed to escape, and how the US might "close THIS loophole" to prevent others from using it.

Comment Re:Simple Fix for H1B Visa Problem (Score 1) 55

Simply require that H-1B visa holders must be paid at least the 90th percentile (or 95th if you like) wage for their field.

Plus any amount that the employer would have to pay into a government entitlement program for a US employee that he doesn't need to pay into said program for a foreigner on H1B (or other work visa systems).

It's even fair. If the program is, say, a retirement program that the visiting worker can't benefit from, shouldn't he have the money to buy a replacement for it elsewhere?

Comment Dow makes LOTS of stuff. (Score 1) 491

... by everyone's favorite munitions manufacturer: Dow Chemical.

Dow makes a LOT of chemical stuff. Some of it's useful to the military.

If their Dow Corning partnership-subsidiary hadn't been hammered into bankruptct by a bunch of (later shown to be bogus) suits claiming medial harm from their silicon breast implants, we might have had hybrid cars a couple decades earlier, out of Detroit rather than Japan, using lenticular, glass fiber, super flywheels, rather than batteries, for energy storage.

Comment Yeah, you'd think that ... (Score 1) 108

It's my understanding that when you're committing a crime, the last thing you want to do is break even worse laws that will get you a worse sentence if caught.

Yeah, you'd think that. And some of them actually do think of that.

But many criminals don't think very well, or very far ahead. Not thinking about being caught is common. Not expecting to be seriously inconvenienced if they ARE caught is common also.

Think about it: How is "Send me a bitcoin or your insulin pump will deliver a fatal dose!" different from armed robbery for a fat wallet? "Give me a bunch of money or I shoot you!" And a bunch of them DO shoot - (VERY) often even if they GOT the money.

The threat of law-enforcement escalation for murder doesn't seem to have stopped up-front-and-personal armed robbery. Why should it stop distant-and-anonymous ransomware?

Comment Trying to stop it also has bad history. (Score 1) 575

The problem is that the whole thing lends itself to "wackadoodles". You have an entire system of belief based on nothing but hearsay ... Then people believe this stuff with no evidence for it ... take some part of that "literal truth" and decide that it really means you need to go murder some people.

Unfortunately, trying to stop it also has bad history. Meme-infected people tend to remain meme-infected until death when opposed (because opposition tends to reenforce such memes), and forcible brain-washing normally doesn't work (though it may get them to pretend to have changed their beliefs, in order to make the pain stop or avoid death or mutilation). Meanwhile there's a long history of people infected with OTHER religious memes using governmental power to wipe out the believers in competing religions.

The history of Europe, in the centuries before the framing of the US' Constitution, was full of disastrous religious wars, and many of the religious groups in the Americas were here to escape this. One of the groups was "The Separatists", the (colorfully dressed "Pilgrims" of the Plymouth colony, often conflated with the "Puritans" who settled a bit farther north) who held, as a core belief,the separation of the church and the state (because each would corrupt the other).

This ideal was built into the first Amendment of the Bill of Rights, pushed by many leaders of small religions (who knew that, if the government picked and promoted a church, it was unlikely to be theirs, and the religious wars would start over here). The US federal government (and, though "incorporation", the states and their subdivisions) is prohibited from doing anything, for or against, any specific religion (including dogmatic non-religion).

And Islam was known to the framers. It shows up in their debates, where it is held up as an example of a non-Christian religion for which the same arguments can be made, for and against, as are made with respect to Christian sects.

So tracking people by religion, as religion, is right out, and any such plan would almost certainly be gutted the first time it hits the courts.

If the government wants to go after the I.S. brigands, it needs to frame the laws and activities in terms of their civil actions, without respect to any religious motivations or professed religious claims.

Comment What happens if you EAT this salad? (Score 1) 39

Does it get broken down into something harmless in the stomach? Or do YOU get conductive lines along YOUR plumbing?

It's not a minor thing: For starters the heartbeat propagation is partly electrical. Better-than-blood-plasma conductors laid out along the plumbing of the heart might affect the heartbeat in a dangerous manner.

Comment Conspiracy theories and the "Second Cover" (Score 1) 42

... there's always room for a conspiracy theory like the NWO controlling both the US and German governments and then some to suppress the truth.

The problem is that people do tend to work together to advance their own interests, and do so in secret to reduce opposition from others. That is the definition of conspiracy. Such activity is not purely mythical or rare - it's pervasive, inherent to the human condition.

Governments, and groups within and/or associated with them, have a long track record of doing such things, getting away with them for years, and having (some of) them come to light decades later. It's always the same story: "Oh, yes, back in the bad old days there were such things going on. But that stuff isn't done any more. (And anybody who claims such stuff is happening now is a nutcase, so pay no attention to him.)"

Then, maybe 30 or 40 years later what was going on THIS time comes to light, and the story repeats. Or somebody blows the whistle while it's still going on and presents evidence (often at great cost to himself), and then it's "That's just a rogue person/agency/group. We're bringing them to heel." or "It's a corrupt administration. Replace the head of state with a different one (maybe from the other major party but keep the same two parties in power) and it's all taken care of." Yeah, right.

Snowden revelations, ECHELON, Watergate, COINTELPRO, Pentagon Papers, Hanford Experiment, Tuskegee Experiment, Factor 8, Abscam, Ng Lap Seng, Iran-Contra, MK-Ultra, Operations MOCKINGBIRD, PHOENIX, and CHAOS, ... I could go on for pages, and that's just big, US (sometimes with allies), stuff that came to light in MY lifetime.

The government has whole agencies tasked with conspiring in secret to collect information and/or intervene to interfere with any opposition to its interests. The US has "Black Budgets" to unauditably fund such activity, and the Department of Defense, alone, spends an estimated $50 BILLION a year on its portion of this (as of 2009).

With their activities occurring in secret, there is much temptation to, and limited checks on, also targeting the biggest risk to the people currently in power in any government: The citizens of the country.

"Spook" agencies have a number of techniques to keep these conspiracies hidden, and one that has come to light (and is appropos) is the "Second Cover". This consists of spreading TWO cover stories: The first is plausible. The second is tinfoil-hat fruitcake material, lightly hidden. Anybody who figures out the first cover IS a cover and starts digging finds the second cover. Then they usually either give up (rather than dig for a third level) or you get new material for the tabloids, and another boost for the "conspiracy theories are ALL crazy talk" meme. (And it also helps that occasionally they DO try out the odd piece of mystic bulls**t, just to see if any of it, like some herbal medicine, DOES work.)

I generally assume (as did The Framers) that this sort of creeping (or galloping) encroachment is inherent in governments, is going on (and having new project starts) all the time, we usually can't tell, through the fog of misdirection, what's going on NOW, and the job of the people, like a farmer clearing weeds and trimming orchard trees, is to continually cut it back to levels that don't ruin our own lives and livelihoods.

Comment I wish they'd ditch daylight savings time. (Score 2) 143

Do you have any IDEA what a mess Daylight Savings Time makes of things like programs for process control and scheduling - and has at least since I did software for it back in the late '70s

Heck: For far longer than that. I hear the railroads handle it like this:
  - In the spring, suddenly all the trains are an hour late. They work their way back to being on-time as they normally would - by running as fast as is practical.
  - In the fall they STOP FOR AN HOUR. They just sit there with their engines running...
It's just easier than trying to figure out something "better" to do about it.

The claims that it saves energy are currently backward and getting more so. They may always have been, or it may be because lighting is more efficient (so the savings is small) while air conditioners are far more prevalent (and run more if people get home earlier).

Meanwhile it increases death rates: From DST-lagged drivers just after a change, from kids getting hit going to school in the dark on more days, from stress-related diseases exacerbated by the stress of the time change.

It also was a big factor in killing drive-in theatres.

If the government MUST twiddle with the clocks seasonally they should set them the OTHER WAY, creating Night Life Savings Time. We ALREADY have a shortage of dark time for evening recreation in the summer. Why take another hour away by shifting the clocks? Add one instead.

"Atomic batteries to power, turbines to speed." -- Robin, The Boy Wonder