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Comment: Re:Let me guess (Score 1) 166 166

It is not clear to me that the big difference lies in the presence or absence of network access. The power lies in the ability to redirect the interface using DISPLAY. Piping through ssh relies on being able to set DISPLAY to a virtual device, e.g. localhost:0.10 and have everything work on this virtual display device disconnected from any hardware and work for every single application.

Whether the commands to the virtual device are sent to an open port 8000 or sent encrypted over an ssh link doesn't seem to be particularly important. It's the initial step of being able to connect any GUI to an arbitrary virtual display that is key. True, X with no security and an open port 8000 allows anyone to start an X client on the display with no local account needed, but I haven't seen this in use since the demise of the X terminal (good riddance. anyone want one? I need to clean out my office).

It seems likely that if Wayland compositors support a version of Xnest, then effective networking will work. But it's the initial level of abstraction that is needed.

Saying that X support will continue as long as codes support X is truly begging the question. The problem is the next time serious modifications to a code are made; in most cases, if network support doesn't happen for free, the developers will not bother.

Comment: Re:Dell Venue 8 7000? (Score 1) 120 120

Who the hell decided to call something "Dell Venue 8 7000"? You don't put two numbers one after another, it's just stupid!

Time to fire the marketing guys!

Sounds like an old phone number. Like buying a Dell Pennsylvania 6-5000.

Comment: Re:The author of the article is confused (Score 1) 227 227

When you are hanging "No Tresspassing" signs on your private property or a "KEEP OUT" sign, do you also include in big print the exception "EXCEPT AS PERMITTED BY LAW" ?

No, and that proves the point, because trespassing means entry without permission. Guests are not permitted to trespass--they are not trespassing by definition. Furthermore, "No Trespassing Signs" frequently cite specific state laws that govern their meaning and interpretation.

Is the assumption that trespassers carry a copy of the state code in their pocket? No, the purpose is to place people on notice that their behavior is governed by specific laws and they are responsible with learning and following those laws. That's all the NFL needs to do.

Comment: Re:The author of the article is confused (Score 1) 227 227

"You are not allowed to copy a description or account from the telecast and reuse their description or account beyond what fair use allows"

Of course. That is why the NFL is being intentionally misleading when they refer to "Any other use of this telecast or any pictures, descriptions, or accounts of the game." They use the phrase "any other use," not "any other use except as permitted as fair use under copyright law." A rational person, not acquainted with the ins and outs of copyright law, would assume that they have no right to repeat a syllable of what they hear.

Comment: Re:And? (Score 1) 448 448

What the TSA agents do at any particular checkpoint is only slightly related to what the rules are as publicized by the TSA.

I have found that showing the TSA agent the rules printed from the TSA website is a waste of time, but being calm and polite can sometimes get them to change their minds.

Comment: Re:hmm.. (Score 1) 571 571

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.

Comment: Re:RF (Score 1) 571 571

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.

Comment: Re:Not New information (Score 3, Insightful) 571 571

>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.

Comment: Re:Sometimes nothing is a pretty cool hand (Score 1) 571 571

>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.

Comment: Re:wow (Score 4, Informative) 571 571

>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).

Comment: Re:hmm.. (Score 1) 571 571

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.

Comment: Re:Fusion in some forms can be very dangerous. (Score 1) 571 571

> 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.

Comment: RF (Score 1) 571 571

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.

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