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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters Re:wow (571 comments)

Lots of gammas produced as result of the interaction of fast neutrons with matter. Not the fusion reaction itself, as you say.

about a month ago
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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters Re:hmm.. (571 comments)

They have a design for a reactor that they think they can scale up to 100 MW. These are not actual performance numbers. In fact, none of the news stories I checked from links here have any actual performance numbers at all--input power, fusion power, plasma density, plasma temperature.

A device generating 100 MW of fusion in that way would be using 10s of MW of power for magnetic fields and RF generation, enough to run a small town (if only for a few s at a time). This would be a major facility. Not to mention that it would be permitted and inspected like any other nuclear power plant.

There is a huge number of hard issues to deal with if a device starts making MW of fusion power. Just MW, not 100s of MW. At 100 MW, most superconducting magnets are wrecked, special vacuum pumps for dealing with tritium are needed, immense neutron shielding is needed, wires and structural elements become embrittled, fiber optics are browned...The obvious absence of any mention of these tells us just what level this device is operating at. Not saying it won't work, but that the step from making a cold plasma to MW of fusion power is not a small step.

about a month ago
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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters Re:RF (571 comments)

What you are referring to can be relevant. If the wave reflects, the fields will penetrate some distance past the reflecting layer and interact with particles in the so-called evanescent region. But that is not the main issue. When the plasma sits in a magnetic field, the wave interacts with the motion of the particles around the field lines in a complex manner, further complicated by the way the difference in ion and electron mass causes them to react very differently to the RF wave. The dominant effect comes from the RF frequency and where it sits with respect to the other characteristic frequencies of the particles moving in the background magnetic field. If the frequency is in the right band, an RF wave will pass right through plasma with strong diffraction but no absorption.

about a month ago
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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters Re:Not New information (571 comments)

>Magnetic mirrors have already been proven not to work.

They do have a huge problem that no one was able to solve. It is not inconceivable that someone who understands the problem will be able plug the ends. But step one is to explain why this mirror would work differently from those mirrors.

about a month ago
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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters Re:Sometimes nothing is a pretty cool hand (571 comments)

>hype until proven

The geometry and stability arguments make this look like a variation on a mirror, and people figured out the advantages and the disadvantages of mirrors a long time ago. The instabilities that dump power into the unconfined particles are not always obvious until you know to look for them, so until they ramp this up to a couple keV, there is no telling if it is promising or not. Maybe with modern technology, they can make it work.

about a month ago
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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters Re:wow (571 comments)

>I'm baffled why it isn't crazy radioactive.

It is! Nontechnical discussions aren't very good at differentiating between three somewhat different areas of concern. First, neutrons and gammas produced by the reaction need to be shielded but go away when you turn the reaction off. Second, short-lived activation in which materials are radioactive, but with a half-life of years or less that becomes safe in a reasonable time. Fusion reactors have both of these, but they are manageable. Third, fission leaves behind nuclear waste materials with a half-life in tens of thousands of years--this is nasty stuff and is around basically forever. Fusion produces no long-lived waste (there is probably some component of some alloy that will prove to make tiny amounts of bad waste, but nothing significant compared to fuel rods from fission reactors).

about a month ago
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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters Re:hmm.. (571 comments)

If they can build and test it within a year, why would it still take about 10 years to actually produce an operational one..

First, because it won't work as expected as they try to scale it up, and new problems will have to be solved.

Second, because the engineering problems related to extracting energy from fusion and maintaining the reactor hardware in a bath of energetic neutrons are huge problems that people have been working on for decades and haven't completely solved yet.

about a month ago
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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters Re:Fusion in some forms can be very dangerous. (571 comments)

> People, its not a troll. Read the argument carefully. Its a real concern.

Yes it is a troll and no it isn't a real concern. If the poster hasn't figured out that the mass of hydrogen converted to helium is utterly negligible compared to the mass of water in the oceans, then he or she shouldn't have posted in the first place. This is no more reasonable than saying that the reactors will produce n-waves that interfere with instructions beamed from our galactic overlords and demand that others refute it.

about a month ago
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Lockheed Claims Breakthrough On Fusion Energy Project

Crispy Critters RF (571 comments)

Whether RF is absorbed, reflected, or passes right through depends on the wavelength and polarization of the RF waves, external magnetic field, and plasma density and temperature. There is a zoo of resonances, evanescent layers, and nonlinear mechanisms to consider. The effects of gradual changes in plasma parameters can be understood in approximation, but if there are sharp gradients in the plasma parameters you need 3d modeling and a prayer.

about a month ago
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New DNA Analysis On Old Blood Pegs Aaron Kosminski As Jack the Ripper

Crispy Critters Re:forensic 'science' (135 comments)

Agreed. You can't compare to a database of a million individuals. In this case, though, it seems the person fingered was already one of a small number of those suspected. That would eliminate the statistical argument in this particular instance.

about 3 months ago
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Author Charles Stross: Is Amazon a Malignant Monopoly, Or Just Plain Evil?

Crispy Critters Re:Publishers are Dinosaurs. (405 comments)

Many authors would rather write than worry about finding and paying for editing, proof reading, cover art, advertising, promotional travel, etc. They are capable of it, but would rather spend their time doing what they do best, which is write. Also, they would rather work under contract with some guaranteed income rather than shoulder all the risk themselves.

about 6 months ago
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Author Charles Stross: Is Amazon a Malignant Monopoly, Or Just Plain Evil?

Crispy Critters Re:Pretty stupid reasoning (405 comments)

People who are not involved in the publishing industry think it would be great for authors to self publish. Interestingly, authors seem to think almost uniformly that it is a terrible idea. The authors, who have a very good idea just what publishers can add to the book, mostly really really like what publishers do for them.

The authors also don't think that they will make more money by self publishing either, because they know how much less they will be writing because of the time spent on other tasks currently handled by the publisher.

about 6 months ago
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Author Charles Stross: Is Amazon a Malignant Monopoly, Or Just Plain Evil?

Crispy Critters Re:Do we really need new books? (405 comments)

The flaw in your argument is clear in that you are pirating books to read. The argument should work the same if you limit it to works on Project Gutenberg, which are available legally. There are more books written before 1900 than I will ever read. But I want to read books written after that, because the world has changed. You do want to read recent books by pirating them. But if there are no new books, then in some number of years all the books will be about a distant and foreign world without the same relevance to us.

about 6 months ago
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Malaysia Airlines Flight 370: Experts Unable To Replicate Inmarsat Analysis

Crispy Critters Re:Not so.... (245 comments)

Sigh. Posting erase moderation b/c I accidentally moderated you down instead of up.

about 6 months ago
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Firefox 29: Redesign

Crispy Critters Re:tabs (688 comments)

Indeed. I never figured out why everyone dumped Mozilla for Phoenix in the first place. (The memory usage and speed were identical for me on Linux.)

And a firefox is a freaking PANDA, not a fox, so change the stupid logo. Yes, I DO get insanely annoyed over pointless things, thank you for asking.

about 7 months ago
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Ask Slashdot: Professional Journaling/Notes Software?

Crispy Critters Re:Paper for me too (170 comments)

"On the computer side, a folder with the name of the project/task/whatever to dump digital stuff related to it."

I also always use filenames like 20140420.txt. Graphics get names like 20140420.jpeg. Search with grep, back up with rsync, remote access via ssh. This works for me because (1) most of my notes are text and (2) keeping the material readable for 10 years or longer is a requirement. Take notes by hand in meetings and transcribe later, which means I rewrite them into English while I still remember what happened.

about 7 months ago
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Bill Gates Patents Detecting, Responding To "Glassholes"

Crispy Critters Re:The difference... (140 comments)

"The problem is that people get irritated when people are casually pointing cameras at them the whole time."

Good theory, but does it match the data? Are the people being assaulted for wearing google glasses being assaulted when they have been pointing the glasses at someone for an extended period of time in an environment when they expect to not be recorded? Or have the attacks occurred in public places which are likely already under video surveillance and full of people snapping photos of friends and bystanders?

Alternative theory: People like hating on overt geekiness. Hypothesis: If hovercars were invented and were sold for ten million dollars each, people would love them, but if only geeky hobbyists had them, people would smash them in the street.

about 7 months ago
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How Satellite Company Inmarsat Tracked Down MH370

Crispy Critters Re:Doppler seems wierd (491 comments)

I don't follow your comment.

The question is what if anything breaks the symmetry between north and south. The answer appears to be (from the comment you linked to) that the satellite has a significant motion with respect to the Earth's surface, even though it is in geosynchronous orbit.

There are still two possible paths, a north and south one. But because of the motion of the satellite, one path will be straight at a reasonable speed, and the other will be curved and too fast or too slow to be realistic.

about 8 months ago
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How Satellite Company Inmarsat Tracked Down MH370

Crispy Critters Re:Doppler seems wierd (491 comments)

It doesn't seem that anyone has an answer to this question. There is some other source of information or another assumption that is not being shared with the public. The claim is that all the data is from the single Inmarsat, so there is no other data to add in to triangulate. The satellite is in geosync, so we can ignore relative motions. Unless somehow the wobble of the orbit is large enough to have some effect over 8 hours. There could be some assumption about the route--for example like assuming the plane will fly flat and level at a constant relative air speed and then adding in prevailing air currents. Or some other reason to believe the plane would not be flying straight relative to the ground.

about 8 months ago
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Malware Attack Infected 25,000 Linux/UNIX Servers

Crispy Critters Re:Well, I'm clean AND I'M INFECTED?! (220 comments)

Other posters explained (so this is redundant -1). ssh is supposed to claim -G is illegal or unknown depending on the version. The backdoored version DOESN'T complain, which is the indication. But "-g" is a legitimate option, so there is no complaint from either the safe or hacked version.

about 8 months ago

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