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User: wagnerrp

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  1. Re:how much power does a 1MW laser need? on Navy Planning To Build Laser Cannon In Four Years · · Score: 1

    Simple. You run bleed lines off that boiler to a secondary turbine hooked up to a generator. On more modern ships, you pull shaft power straight off the gas turbines.

  2. Re:Absorb the energy and use it to get away on Navy Planning To Build Laser Cannon In Four Years · · Score: 1

    Isn't that what piezoelectrics are for?

  3. Re:Firing range on Navy Planning To Build Laser Cannon In Four Years · · Score: 1

    A supercavitating torpedo is completely blind, and very VERY track-able. It relies on the control wire from the submarine that launched it for guidance. All you have to do is maneuver somewhere other than where it predicts you to be, or deploy some form of depth charge in its path.

  4. Re:Somebody shake that mans hand on Australian WiFi Inventors Win US Legal Battle · · Score: 1

    we patent our own stuff just the same as the Australians .

    I sort of thought that bit was implied.

  5. Re:Priorities. on Navy Planning To Build Laser Cannon In Four Years · · Score: 1

    So in other words, Defense spending keeps getting progressively less and less of the federal budget, but the federal budget and GDP just keep growing to compensate.

  6. Re:Somebody shake that mans hand on Australian WiFi Inventors Win US Legal Battle · · Score: 1

    What I'm saying is that I didn't think governments were allowed to own patents. I thought any such research immediately entered public domain. Although a brief search through various US national laboratories shows we patent our own stuff just the same.

  7. Re:Somebody shake that mans hand on Australian WiFi Inventors Win US Legal Battle · · Score: 1

    A bunch of scientists took government funds through a government owned facility, did research, created new technologies, and patented it. That means the government subsequently owns the patent, and not a private institution or individual. I thought there was some kind of clause in most patent laws that exempted governments from being able to own patents. You release it into the public domain, companies use it, make money off of it, and you recoup the expenses in increased tax revenue. If the patent is worthwhile, you're not supposed to need the licensing fees.

  8. Re:Misleading on New Engine Raises Possibility of Cheap Travel To the Moon · · Score: 1

    We know how to do that, but all of the proposed systems either can't be used for complex (and organic) payloads, or leave large swaths of scorched Earth in their wake.

  9. Re:From Where? on New Engine Raises Possibility of Cheap Travel To the Moon · · Score: 2

    Despite the futility of responding directly to an AC, there are inherent limits to an electrostatic (ION) drive. You increase your exhaust velocity by increasing your voltage, however if you increase your voltage too far, you arc between your electrodes and waste all your power. The only way to increase velocity is to build larger, increasing your gap, to allow for higher voltage. This actually achieves a higher exhaust velocity than it should by "cheating" in a pretty ingenious fashion. Rather than using one electrode to ionize the propellant, they're starting with an electrolyte, and using alternating current to prevent the build up of DC bias between the grid and the solution, effectively halving their operating voltage for the same performance.

  10. Re:Sweet! on New Engine Raises Possibility of Cheap Travel To the Moon · · Score: 2

    You misunderstand. Your car is fueled by gasoline, which drives the pistons. This "new engine" is fueled by a nuclear reactor, or solar, or whatever, and the tenth liter of "fuel" is just inert reaction mass. There is no energy to be extracted from it, it's merely something to push off of.

  11. Re:Too long on Software-Defined Radio For $11 · · Score: 3, Informative

    I'm sure 99.999% of the population who thinks "radios" are something they're listening to music on have exactly zero reason to know what a software defined radio is. The rest remainder of us who actually understand technology can use whatever terminology we see fit.

  12. Re:better get on Software-Defined Radio For $11 · · Score: 1

    Good thing it's a European tuner then...

  13. Re:And now for the obvious question... on Tegra 4 Likely To Include Kepler DNA · · Score: 1

    Since you can't even be bothered to read the first sentence in the summary, it is the code name for their new GPU architecture, starting with the GTX680.

  14. Re:Big surprise on MIT Solar Towers Beat Solar Panels By Up To 20x · · Score: 1

    Growing up does not net you any more energy as a whole. The purpose for plants and trees to grow up is to beat their neighbor out for access to that sunlight. Natural selection is inherently selfish. Were we intelligently designed, the world would be flat and covered in a thin layer of green algae. You erect your massive solar tower in your own backyard, and now your neighbor can't get a sun tan.

  15. Re:Duh on MIT Solar Towers Beat Solar Panels By Up To 20x · · Score: 1

    Except you building your solar array up means someone else is going to be in your shadow, and not receive any sunlight. There's not any real advantage to this system.

  16. Re:Duh on MIT Solar Towers Beat Solar Panels By Up To 20x · · Score: 1

    When the Sun is low on the horizon, their vertically mounted cells are 20x more efficient than the panel mounted parallel to the horizon. This discovery brought to you by 4yr olds making their first discoveries into basic spatial reasoning.

  17. Re:Economies of scale on Hoover Dams For Lilliput: Does Small Hydroelectric Power Have a Future? · · Score: 1

    The second one was the use a new novel chemical means of storing hydrogen at low pressure.

    Got any links for that? The closest I heard to something actually useful was storage in dried ammonium salts, but I've not seen anything further done with that in years.

  18. Re:Local Energy and Efficiency are the Future on Hoover Dams For Lilliput: Does Small Hydroelectric Power Have a Future? · · Score: 1

    When it's 30 outside my house, it's still 60 underground. When it's 90 out, it's still 60 under. With a heat pump, I can harness that energy differential.

    A heat pump uses energy to create a heat differential. A heat engine uses a heat differential to output energy. You are claiming the other way around. At a meager 5% temperature difference between your hot and cold sinks, the energy that can be extracted is so abysmally small as to not be worth trying. There is good reason why engines run combustion temperatures of many thousands of degrees. What that 60F ground temperature DOES get you is cheaper operation of a heat pump to heat or cool your home.

  19. TW, singular, not plural. Our current electrical production capacity in the US is right at about 1TW, with yearly average consumption running roughly half that value. That's 2% of our peak output, or 4% of our average, and they're only talking about capacity in the state of Kansas, a particularly dry and flat state generally not considered at all conducive to hydroelectric generation.

  20. Re:Economies of scale on Hoover Dams For Lilliput: Does Small Hydroelectric Power Have a Future? · · Score: 4, Insightful

    You can transfer it quickly, but storage is a pain, and from water to hydrogen and back to water, the best returns aren't even hitting 50%. Nearly all of our hydrogen is produced by cracking petroleum, because electrolysis is just so inefficient.

  21. Re:Economies of scale on Hoover Dams For Lilliput: Does Small Hydroelectric Power Have a Future? · · Score: 3, Informative

    Replacing oil with a plant-based fuel makes no sense. The best plants convert around 10% of light into growth, of which only a fraction is recovered as fuel during harvesting, and only a fraction of that is recovered as usable energy when that fuel is consumed. Even lousy consumer-grade photovoltaics make far better use of sunlight than plants. If you want to spend gobs of money replacing our existing petroleum infrastructure, why not spend it on cheap, high capacity, powerful batteries?

  22. Re:COOL!!! on Supreme Court Throws Out Human Gene Patents · · Score: 0

    Was he going to be involved in a hit-and-run accident with a '93 Ford Escort station wagon?

  23. Re:Listen to what I have to say on HDTV Expert Alfred Poor Tells You What to Buy and What Not to Buy (Video) · · Score: 1

    As for 3D TVs, honestly I think the TV industry is just trying to cash in and get people to replace their perfectly good 2D HDTVs. Since that obviously wasn't the moneymaker they'd hoped it would be, they're pushing the Smart TVs ("oh boy, my TVs firmware is out of date and my model is no longer supported, time to buy a new one!"). The only thing that I'm mildly enthusiastic about is the new 4K sets, but honestly, it's going to be a long time before I consider upgrading my current set.

    That's EXACTLY what's going on. Digital and HD TV came out, and TV manufacturers had good times for better than half a decade. First there were 720p sets, and then 1080p sets, and then 120Hz and 240Hz sets, and then the LED backlighting. Then, everyone who wanted an HD set had one, and the market is drying up. Now we get stereoscopic (I refuse to call it "3D") and smart TVs, trying to produce a market and drive up sales for things that people don't actually want. Stereo still isn't selling strong, and people who actually want a "smart TV" are going to produce their own by attaching some cheap device, that they can cheaply replace in 2-3 years without having to buy a whole new TV. There's not going to be a worthwhile reason to upgrade until someone brings SED back, OLED becomes affordable, or we start ramping up in useful resolution.

  24. Re:Perspective, people, perspective on Ask Slashdot: How Would Room-Temp Superconductors Affect Us? · · Score: 1

    The most common fuel for liquid rockets are RP-1 and LO2, RP-1 being very pure kerosene. An LH2 rocket is significantly more efficient than an RP-1 rocket, which is in turn significantly more efficient than any solid fueled rocket. It's damn tough to get a solid rocket just into orbit, and trying to get one just to the Moon would require such a high fuel fraction as to be unachievable.

  25. Re:Great About Time on Tennessee Passes Bill That Allows "Teaching the Controversy" of Evolution · · Score: 1

    Yes. There is no evidence. There are only stories. You can't create scientific controversy or any form of discussion if you have no data to back up any of the proposed theories.