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Comment: Concorde MKII (Score 2) 93

by Goonie (#49604197) Attached to: NASA Gets Its Marching Orders: Look Up! Look Out!
Republicans hate big government, except when it comes to a) building big machines designed to kill people, and b) firing rockets into space.

Republicans have been the primary Congressional force running interference for the old space industry, either by throwing money at the likes of ATK to build rockets that will never fly, or actively blocking SpaceX from competing with the established players on contracts.

While the big government contracting model can get crews into space, it does so at such an exorbitant price it's simply not worth it. SpaceX, or more precisely the discarding of legacy design and especially legacy contracting models that SpaceX represents, at least gives us a chance of a sustainable space program because it is far, far better value for money. It's also far more in alignment with professed Republican principles, as distinct from revealed preferences from observed behaviour.

A revived crewed space program under the old model will result in bugger-all flying, lots of money wasted, and will get cancelled soon enough. Why bother?

Comment: Re:More religious whackjobs (Score 1) 214

by Rei (#49602743) Attached to: Native Hawaiian Panel Withdraws Support For World's Largest Telescope

It's the same reason why many of the oppose geothermal power, keeping Hawaii reliant on burning oil for most of its electricity. Also why there's opposition to even trying to redirect lava flows as most countries do when their people are threatened (with a number of successful redirects having been achieved).

Apparently Pele wants people to be ignorant of the cosmos, to destroy the climate, and to lose their dearest possessions without putting up a fight.

Comment: Re:He's also an interesting candidate for this (Score 2) 235

by dpilot (#49602405) Attached to: Bernie Sanders, Presidential Candidate and H-1B Skeptic

I'm generally in favor of free market capitalism, but sometimes I'm not sure that's what I'm seeing right now. I also think that problems arise when revenue and profit become the number one goal, especially at the expense of the products and services that are supposedly being sold for that revenue and profit.

Comment: Very old debate (Score 1) 424

by Goonie (#49602153) Attached to: My High School CS Homework Is the Centerfold
For what it's worth, this has been discussed for many years, and these researchers have a rather humorous partial solution.

My take: it's not the world's biggest problem, but if it's necessary to provide comparisons with earlier papers go ahead and use Lenna, go right ahead. If you just need to illustrate a technique on human skin tones, pick something else and stop needlessly pissing people off.

+ - Bernie Sanders, H-1B skeptic

Submitted by Presto Vivace
Presto Vivace writes: Will the Vermont senator raise the visibility of the visa issue with his presidential run?

The H-1B visa issue rarely surfaces during presidential races, and that's what makes the entrance by Sen. Bernie Sanders (I-Vt.) into the 2016 presidential race so interesting. ... ...Sanders is very skeptical of the H-1B program, and has lambasted tech firms for hiring visa workers at the same time they're cutting staff. He's especially critical of the visa's use in offshore outsourcing.

Comment: Re:This again? (Score 1) 416

by Rei (#49599695) Attached to: New Test Supports NASA's Controversial EM Drive

I've seen plenty of work on accelerator-drive heavy isotope reactors but nothing for light isotope reactors like lithium. Accelerator driven heavy isotope reactors still deal with many of the problems of conventional fission reactors - they're greatly improved in many regards, but still problematic (you still have some plutonium, you still have some fuel availability/cost limitations, you still have some long-lived waste, you still have some harder to shield radiation, you still have a wide range of daughter products making corrosion control more challenging, etc - just not to the degree of a regular fission reactor). A light isotope reactor using lithium would virtually eliminate all of these problems. And it has a higher burnup ratio, which is of course critical for space uses.

And while everything I've seen about past improvements in accelerator efficiencies and spallation process improvements, and what's being worked on now, suggests no limit any time soon on neutron production efficiencies - at least that's how it looks from the papers I've read. Plus, even if efficiencies couldn't be improved any further (there's not that much further one needs to go), one could hybridize a heavy isotope and light isotope reactor, using a heavy isotope target as a neutron multiplier to bombard the lithium. You'd require significantly reduced quantities of heavy isotopes relative to a pure heavy isotope reactor, and most of the energy from the lithium side could be as mentioned captured without Carnot losses, which is a big bonus. Any non-thermalized neutrons of sufficient energy would produce tritium as a byproduct, which of course would be a value-added product - in fact, given that the tritium-breeding reaction with 7Li and a high energy neutron yields a lower-energy neutron, the thermalization could potentially be done via tritium breeding in the first place. And tritium is a valuable product whether one has interest in D-T fusion or not.

I just think it's weird that I've not come across any work on a lithium-based accelerator-driven spallation reactor, and was just wondering if there's a reason for that. It certainly looks appealing to my non-expert eyes. I mean, it looks even cleaner and more fuel-available than D-T fusion, and looks closer to being viable on a full-system perspective. Versus accelerator-driven heavy isotope fission you get less power per neutron (about a quarter as much), of course, even accounting for Carnot losses in the former - but that's not what matters. Cost is what matters, and if you're eliminating the use of super-expensive fuel, not producing any costly-to-manage waste, have no incident radiation, no proliferation concerns, etc, you're completely changing the cost picture - without even considering the possible joint production of saleable tritium.

Comment: Re:FCC shouldn't regulate this - it's FTC's job. (Score 1) 430

by Ungrounded Lightning (#49598215) Attached to: Rand Paul Moves To Block New "Net Neutrality" Rules

Good. Now we've gone from "they're all scum" to "some of them (possibly including Rand Paul") are good and trying but the Repubican machine and its operators will block them."

At this point we're mostly on the same page.

Ron Paul is clearly one of those good guys. And the Neocons controlling the R party machine (one of the four major factions) steamrollered him and his supporters (sometimes violently), and changed the rules to make it even harder for a grass roots uprising to displace them.

Two debates are going on right now. One is between working through the R party (is it salvagable?) or coming in with a "third" party - either an existing one or a new one (is that doable or do the big two have too much of a lock?)

The other is whether Rand is a sellout to the Neocons or if he's just more savvy than his dad and trying to look non-threatening to them in order to get the nomination. Andrew Napolitano, who knows him personally, says he knows him to be a genuine liberty advocate, and I trust A. N. on this subject.

Comment: Re:Point proved (Score 0) 271

I own a 2001 Honda Insight hybrid modified to be a PHEV and plugged in nightly to charge on geothermal power.... and a Ford Ranger ;) The "why" is obvious, because I have regular needs to carry big heavy things, now that I own land in the countryside. Back when I had no such need... I didn't own any such vehicle.

I guess it's hard for him to imagine that a woman would have a need to carry large and/or heavy items?

Comment: Re:this is science, so you have to ask... (Score 4, Informative) 271

And the crazy thing is, they did consult with male colleagues before publishing. The reviewer just assumed that because two women submitted a paper with a conclusion that he disagreed with, that it's specifically because they're women "making ideologically biased assumptions" who refuse to talk to men.

Comment: Re:This again? (Score 0) 416

by Rei (#49596849) Attached to: New Test Supports NASA's Controversial EM Drive

Oh hey, since we've got (assumedly) a lot of physics nerds on this thread, and because my mind hasn't suddenly stopped being curious about random topics even though I grew old: here's one of my more recent things that left me with unanswered questions:

One of the commonly cited tritium-generating reactions is 7Li+n(>2.466 MeV) -> 4He + 3H. But is 7Li not also capable of transmutation to 8Li via slow neutron capture? If so would that not yield a 16.004 MeV beta to 8Be, and then immediately into 2 alphas with an additional energy of 0.092 MeV? If so, is there not potential for a future nuclear reactor? Spallation currently yields neutrons for about 25MeV each. If one could cut that in half or less - which I don't see any laws of physics in the way, just improvements in accelerator efficiencies and the spallation process - could this not yield a net positive, using direct deceleration/capture of the beta to generate power without having to suffer Carnot losses? And if so, would that not be a very desireable reactor - nonproliferative, abundant fuel, harmless waste, high ratio of fuel to energy conversion, direct spacecraft thrust possibilities, etc? Or am I totally off base here?

Comment: Re:This again? (Score 1) 416

by Rei (#49596423) Attached to: New Test Supports NASA's Controversial EM Drive

Haha, my concept as a child was to have a buoyant container on wheels in a tube full of water that would rise up, roll down a ramp on the other side, and re-enter the tube through an airlock on the bottom.

Wish my dad had taken the time to tell me why it wouldn't work rather than just saying "perpetual motion is impossible".

Comment: Re:This again? (Score 4, Insightful) 416

by Rei (#49596401) Attached to: New Test Supports NASA's Controversial EM Drive

Or, rather than all of physics being wrong, maybe they have an erroneous measurement setup.

That doesn't mean you shouldn't investigate anomalous measurements. But at this stage you shouldn't be writing fluff pieces with page after page of how much your new technology will change spaceflight. You should be publishing a paper with a name like "Measurement of anomalous thrust in a microwave apparatus operated in a hard vacuum" and trying to avoid the media insomuch as possible - and when you need to talk with them, trying to explain "we don't know what's going on... we have some theories but they're controversial... we need to do more testing." etc.

Comment: Re:inventor? (Score 1) 416

by Ungrounded Lightning (#49596369) Attached to: New Test Supports NASA's Controversial EM Drive

If nobody knows how it works, how did the guy invent it?

LOTS of stuff gets invented without the inventor knowing HOW it works, underlying physics wise. All that's necessary is to notice THAT it works, work out some details of "if you do this much of this you get that much of that", and engineer a practical gadget.

As they say, most fundamental discoveries don't go "Eureka!", they go "That's odd ..."

"When the going gets tough, the tough get empirical." -- Jon Carroll

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