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User: dak664

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  1. Re:ethics of killing and warfare on How Asimov's Three Laws Ran Out of Steam · · Score: 3, Interesting

    Moral killing may not be that hard to define. Convert the three laws of robotics into three laws of human morals by taking them in reverse order:

    1) Self-preservation
    2) Obey orders if no conflict with 1
    3) Don't harm others if no conflict with 1 or 2

    To be useful in war an AI would have to have to follow those laws, except that self-preservation would apply to whichever human overlords constructed them.

  2. I confess to being stupid but endeavor to learn. Your blind spot seems to be the assumption that in equilibrium the radiation from an object must re-emit the same energy per Hz as acquired from the absorption spectrum. Classical thermodynamics, while powerful, leads to an incomplete picture. Statistical thermodynamics says the incoming energy is rapidly randomized among probable states (fortunately for life some of those may start the electron transport chain). The excess energy populates an increasing number of available states until enough of them dissipate (or in vacuum radiate) the excess energy away. Which has very little connection with some hypothetical temperature of the incoming radiation.

  3. In thermal equilibrium with the environment, not with each other. An object absorbing more high frequency radiation has to get hotter to radiate that energy at the lower frequencies. Thus any measurable temperature is a property of the object, not the radiation field. You could define the temperature of vacuum as that of a gray body in equilibrium with the local radiation if that makes you happy. Not sure how useful such a definition would be.

  4. A thermometer coating with high absorption for solar wavelengths and low emissivity at longer wavelengths would get hotter than one with the opposite characteristic when placed near the Sun. Indeed you could run a heat engine off this temperature difference and as you say it would ultimately be powered by the continuing incident radiation. But the vacuum environment has no inherent temperature of its own, rather a radiation flux which can heat different objects to different temperatures even when both are in thermal equilibrium.

    If you enclose a vacuum in a black box with walls at 1 kelvin what is the temperature of the vacuum? If you heat one wall to 5000 kelvin what is the temperature of the vacuum? Is there a gradient? Does it become anisotropic and depend on the orientation of the thermometer?

  5. But in that case the thermometer is measuring its own temperature, not "the temperature of the vacuum", whatever that means. And selective coatings with different absorption and emission spectra could change the reading of the thermometer. Does that change the "temperature of the vacuum"?

  6. Re:kWh/day is stupid. on Tesla Model S Has Bizarre 'Vampire-Like' Thirst For Electricity At Night · · Score: 1

    Under SI convention units are always lower case and the abbreviation is capitalized only when the unit derives from a personal name.
    So 1 watt = 1 joule/second or 1 W = 1 J/s

    Metric prefixes mega and larger are abbreviated upper case, kilo and smaller lower case. MWh, kWh

  7. Party on! on Are Shuttered Gov't Sites Actually Saving Money? · · Score: 2

    And now Congress is considering legislation to assure that furloughed workers get back pay for the vacation.
    http://www.usatoday.com/story/news/politics/2013/10/04/obama-backs-backpay-furlough-shutdown/2923221/

  8. Re:vs gasoline cars on Tesla Model S Catches Fire: Is This Tesla's 'Toyota' Moment? · · Score: 1

    Watch closely and you will discover they explode several times from multiple angles.

  9. Re:Hey guys, seriously. on Pentagon Spent $5 Billion For Weapons On Day Before Shutdown · · Score: 1

    The 1930s technocracy movement outlined a society without money, thinking that it and "The Price System" inevitably lead to overconsumption and collapse. They suggested replacing it with energy chits equally distributed among the population, valid for one year to prevent debt accumulation.

    http://www.technocracy.org/study-guide

  10. Re:Let us opt out. on Tech In the Hot Seat For Oct. 1st Obamacare Launch · · Score: 1

    Lyndon Johnson started the shenanigans with his "unified budget" that included trust funds not subject to budgetary legislation, and over the years Congress used the concept for further obfuscation (such as pinning automatic budget cuts to the unified budget rather than the actual budget).

    I have no idea what the current situation is, but the SS trust funds were officially off-budget as of 2005 according to http://www.ssa.gov/history/BudgetTreatment.html

    "present law mandates that the two Social Security Trust Funds, and the operations of the Postal Service, are formally considered to be "off-budget" and no longer part of the unified federal budget."

  11. Re:space & time as emergent properties on Physicists Discover Geometry Underlying Particle Physics · · Score: 1

    Much of that analysis might be applied to the photon, as a purely mathematical construct to explain the quantized transfer of action between two events having (by definition) no separation in space-time. However electrons are affected by the intervening space even when there is no interaction, e.g. http://en.wikipedia.org/wiki/Aharonov-Bohm_effect

  12. Re:Weasel words on Obama Admin Says It Won't Fight Looser Marijuana Laws, With Conditions · · Score: 1

    Big industry was behind both making both alcohol and MJ illegal. Competition from alcohol and hemp products threatened to constrain the profits of Standard Oil, DuPont, and General Motors. Prohibition was allowed to end after Ford was forced to stopped making engines that could use ethanol blends.

      Interesting history here http://www.starchiefpress.com/articles/article35.html.

  13. Re:This is more sensationalism than any real threa on Collision Between Water and Energy Is Underway, and Worsening · · Score: 1

    An impoundment does result in a surprising increasing of evaporative loss compared to the free-river run. So a nominally non-consumptive water use such as hydroelectric generation or river cooling of the condenser can involve considerable fresh water loss, usually only important to downstream consumers.

    Cooling towers are by definition totally consumptive and are also comparatively expensive so they are mostly used for nuclear plants which make steam at a much lower temperature than coal plants. Thus the small reduction in enthalpy at the top of a cooling tower translates into a couple per cent increase in thermodynamic efficiency and a significant ~5 increase in profit.

    Nuclear plants *could* be run at a much higher temperature, but only the French have the guts to do that :)

  14. Cut that out please... on NSA Releases Secret Pre-History of Computers · · Score: 1

    My page loads have slowed to a crawl!

  15. Yes, it's safety and effectvieness on New Drugs Trail Many Old Ones In Effectiveness Against Disease · · Score: 1

    That's all that has to be demonstrated for a new drug, at least in the US. Not that it is more effective than a previous drug, only that it is safe and more effective than a placebo. So a new version of an old drug might replace a phosphate group with a sulfate group, and it does not matter if the new drug is less effective than the old one, it can be patented and handed over to the marketing department for another 15 years of cash flow. There are a million variations possible, rinse and repeat as needed to maintain the monopoly and high price.

  16. Re:Nice idea, wrong problem on Electric Car Startup 'Better Place' Liquidating After $850 Million Investment · · Score: 1

    So swap the passenger compartment onto a new chassis. No special equipment required, drive the chassis into the cab similar to the way tractors pick up front end buckets. If you buy only the cab and rent the chassis then Initial purchase cost would be small. You could switch between long distance, short distance, truck, limo, mini chassis as needed.

  17. Re:Well... on Of 1000 Americans Polled, Most Would Ban Home Printing of Guns · · Score: 1

    Sorry, I have a patent on that. Rounded sticks are ok, at least until I can come to an agreement with Apple.

  18. There are public ip4 to ip6 gateways on Home Server On IPv6-only Internet Connection? · · Score: 1

    E.g. adding ip4.sixxs.org to the ipv6 address, http://ipv6.google.com.ipv4.sixxs.org/

    Don't know if any allow numerical addresses. Is the ISP providing DNS service for adding your own AAAA records to your routed subnet?

  19. Re:MAME on Ask Slashdot: Really Short Time Wasters? · · Score: 1

    Visual pinball emulates a boatload of the games from the '30s to the '70s, and also has many original tables (I can recommend the Three Stooges) Most are unlocked so you can diddle with the scripts or layout (e.g. flipper length and power).

    It also integrates with MAME for playing ROM-based tables.

  20. Re:You can't get pure alcohol that way on Corn Shortage Hampers US Ethanol Production · · Score: 1

    And that last bit of water comes back during storage in a vented tank. Worse yet someone intentionally cuts it with water to make a few more bucks.

    An easy test for water in gas is to put 50ml of gas into a calibrated plastic bottle, add 50ml of water, cap tightly, and shake. Considerable pressure is generated so don't use your thumb in place of a cap . After settling the ethanol and water will mostly be pulled out of the gasoline into an upper water layer.
    A dividing line at 40ml means 20% ethanol+water in the original fuel. Dispose of the residue responsibly ;)

  21. Re:Who cares if we are hungry... on Corn Shortage Hampers US Ethanol Production · · Score: 1

    Don't know about Sthil, but a small engine carburetor does not have the exhaust sensor feedback to fuel injectors. Fuel with less energy per volume will burn leaner so the engine will run hotter and become more likely to seize. The ethanol allows for a water fraction that makes the situation worse. Backing off the needle valve will compensate, that used to be the quick fix for an overheating tractor engine.

    Avgas 100LL contains no ethanol or water, needs no stabilizers, and is mandated to have consistent properties over a year of storage. Small airports will often let you fill gas cans with it. It is dyed blue to to show that it is leaded and can't be used in automobiles.

  22. Re:Physical Vs. Virtual on Micron Lands Broad "Slide To Unlock" Patent · · Score: 1

    Solving all current problems would be pretty good evidence that your software is not obvious to someone skilled in the art.

    But mere touch screen virtualization of a slide switch that moves only in one direction, or a keypad (visible or invisible) that requires a particular sequence to be drawn to unlock, is no innovation. It's an obvious application of the hardware.

  23. Re:Lunar Lander! on Learning Rocket Science With Video Games · · Score: 1

    The first Lunar Lander was written for the CDC6400 around 1965 and used both console high-speed vector displays. It was amusing enough as a video game but to actually land without running out of fuel required some knowledge of physics. Can't find any images of it, but from this link :

    The 6600 featured parallel functional units and used 10 peripheral processors (PPUs) for distributed processing. It sported the fastest clock speed for its day (100 nanoseconds). The 6600 was the first commercial computer to use a CRT console; CRTs and radar screens had been used on earlier machines. CDC checkout engineers created computer games such as Baseball, Lunar Lander, and Space Wars, which became incentives for getting the machines operational. These are thought to be the first computer games that used monitors.

  24. http://www.marx-brothers.org/info/quotes.htm

    My favorite

    Groucho: "That's in every contract, that's what you call a sanity clause."
    Chico: "You can't a fool a me there ain't no sanity clause"

  25. Re:Clever crafters on Discovery of Early Human Tools Hint at Earlier Start · · Score: 1

    It's called lysdexia, you insensitive clod!