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User: blueg3

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  1. Re:I call BS.kg on EPA Proposes Grading System For Car Fuel Economy · · Score: 1

    I would define fuel input energy as the heat released by burning the used amount of fuel, and electrical input energy as the heat released by running the amount of electricity used (by the charger, not the motor) through a resistance heater.

    So, you'd need to change your fuel energy definition. Otherwise, a car that blows half its fuel, unburnt, out the tailpipe would consume twice as much gas as its efficiency implied. Also, a fair amount of the heat gets dumped into places like tires, which is not easily-measurable. Typically one defines the energy of fuel as the heat energy it releases when burnt in a particular (and efficient) manner. Unfortunately, there are multiple definitions that fall under this, so there are a couple of different "energies" for fuel. Electricity is easy -- the heat emitted by an ideal resistance heater is simply the energy of electricity consumed, which we're already good at measuring.

    I'd prefer a unit of heat energy to one that looks like electrical energy

    Well, it's all energy. BTU is asinine and nobody knows what it is, calories are unused and Calories are for food (don't suggest that people should drink gasoline). You have either Joules, which nobody is familiar with, or kWh, which people are familiar with through electricity. Screwed either way.

  2. Re:Politics And Science Don't Mix on Judge Quashes Subpoena of UVA Research Records · · Score: 1

    They're not really talking about the Pioneer anomaly, just pointing to it to claim that relativity is "wrong". The inclusion of some legitimate questions in physics doesn't magically make the whole list respectable, though. I refer mainly to things like this:
    "The action-at-a-distance by Jesus, described in John 4:46-54."

    Besides a few whoppers, the list consists mainly of already-solved problems and grossly misguided logic.

  3. Re:Well duh. on New QuickTime Flaw Bypasses ASLR, DEP · · Score: 4, Interesting

    This boils down to doing a heap spraying attack, and those are in the general class of exploits that ASLR (and to a lesser extent, DEP) are designed to prevent. However, it's fairly well-known at this point that ASLR can be defeated (sometimes) by well-crafted heap-spraying attacks. (Likewise, DEP can be defeated by stack-smashing using return-oriented programming.)

  4. Re:Suggestions to EPA on EPA Proposes Grading System For Car Fuel Economy · · Score: 1

    Don't they essentially do that with the labels shown, except turn it into a more compelling number -- dollars saved (or spent) on fuel relative to the average?

  5. Re:QR Block information / an app for that? on EPA Proposes Grading System For Car Fuel Economy · · Score: 1

    It's currently a link to fueleconomy.gov/m.

  6. Re:I call BS.kg on EPA Proposes Grading System For Car Fuel Economy · · Score: 2, Informative

    You mean like the second label shown in TFA, which has a section (with a helpful little battery-shaped box to help you find it) that indicates the charge time?

  7. Re:Giant letter? on EPA Proposes Grading System For Car Fuel Economy · · Score: 1

    You mean like the second label shown in TFA?

  8. Re:Giant letter? on EPA Proposes Grading System For Car Fuel Economy · · Score: 3, Informative

    That's weird, because the label they show in TFA is clearly for an electric car, and it lists the following figures:
    kW-hrs/100 miles, MPGe city, MPGe highway

    As I'm sure you're well aware, kW-hr/100 mi is not a rating in miles per gallon. The other two figures are miles per gallon equivalent and are to facilitate comparison across fuel types.

  9. Re:I call BS.kg on EPA Proposes Grading System For Car Fuel Economy · · Score: 1

    Newtons is force. Joules is energy. Although those bastard units, kWh, calories, and BTU, are also energy.

  10. Re:It's all BS on EPA Proposes Grading System For Car Fuel Economy · · Score: 4, Insightful

    With gallons/mile, fuel efficiency is linear instead of inverse-linear.

  11. Re:Politics And Science Don't Mix on Judge Quashes Subpoena of UVA Research Records · · Score: 1

    It's equivocation.

  12. Re:Politics And Science Don't Mix on Judge Quashes Subpoena of UVA Research Records · · Score: 1

    Wow, that list is bad. I mean, painfully, horribly bad.

  13. Re:Politics And Science Don't Mix on Judge Quashes Subpoena of UVA Research Records · · Score: 1

    To be fair, "historical facts" is a term generally reserved for human events that have been recorded in writing. In science, you typically call them "observations". A good set of terms is that the mathematics based on your observations that is supposed to predict future observations is a model or, if it's successful, a law. The explanation of why your model works and how that fits in to the rest of known science is a theory.

    Which means for any reasonably complicated field that can be cast under one umbrella, "theory" is the word that will be applied to it, like "theory of gravity" or "theory of relativity" or "electromagnetic theory". It's a collection of models and some thoughts as to how it is they're all connected.

  14. Re:Hobbies on How To Make Authentic Lightsabers · · Score: 4, Insightful

    It's a shame metalworking and electronics don't have any applications other than building lightsabers.

  15. Re:Different device, same theory on Full-Body Scanners Deployed In Street-Roving Vans · · Score: 2, Interesting

    This is more intrusive than infrared imaging. In both methods, the user can "see" objects that they couldn't see without entering the house or searching the car. X-ray backscatter is an active method, though, sending X-rays at the target and measuring the results, rather than measuring radiation the target was emitting to begin with. I can't see how this will hold up in court, unless it's designed so that it can't "see" objects, but only "detect" very particular classes of objects (e.g., the presence of explosives) and is only used in particular situations where warrant protections are not as strong.

  16. Re:Really? on Full-Body Scanners Deployed In Street-Roving Vans · · Score: 1

    If you measure the relative quantities of these, you can get a pretty good idea of the type of chemical an object is made up of.

  17. Re:not only that on Full-Body Scanners Deployed In Street-Roving Vans · · Score: 2

    There is a background level of ionizing radiation that is more or less unavoidable, and there is an average yearly exposure level due to environmental exposure. As such, there are certainly quantities of radiation exposure that are negligible compared to environmental exposure.

    For that matter, there are legally-defined acceptable levels of occupational exposure to ionizing radiation. (I worked at a synchrotron, where exposure to high-energy X-rays is unavoidable and carefully measured.)

    The reason the dental technician leaves the room when she takes your X-rays is that medical X-rays are actually quite a respectably-large amount of radiation and the technician does quite a lot of X-rays per year.

  18. Re:Neat! on Full-Body Scanners Deployed In Street-Roving Vans · · Score: 1

    Don't antennas generally need to be on roughly the same scale as the wavelength of the radiation they're interacting with? X-rays have nanometer-scale wavelengths.

  19. Re:A bad idea... on Full-Body Scanners Deployed In Street-Roving Vans · · Score: 3, Insightful

    With X-ray exposure, quantity is important. You don't need to be informed that you'll be exposed to X-rays when you fly in an airplane or turn on an incandescent bulb, but you are.

  20. Re:Not a problem on Just Where Is The Lincoln Memorial, Anyhow? · · Score: 1

    With the way DC is designed, if you drive around randomly, you'll probably run right in to the National Mall. The Lincoln Memorial is that big building pictured on the penny. It's across a reflecting pond from the building that looks like the Washington Monument. Sort of in the vicinity of the capitol building, the White House, all of the tourists, and a bunch of Glenn Beck fans.

    I might add that on the Google map that comes up when you search for "Lincoln Memorial" and get the wrong answer, there's a dot a short distance away labeled "Lincoln Memorial". It's that one.

  21. Re:1984 on Wired Youths In China & Japan Forget Character Forms · · Score: 1

    I was wondering when someone was going to make a nonsense reference to 1984. You'd think Slashdotters had only ever read one book.

  22. Re:Time to change? on Wired Youths In China & Japan Forget Character Forms · · Score: 1

    Most people have a hard time with Beowulf or Chaucer, though.

  23. Re:Why not just use Pinyin? on Wired Youths In China & Japan Forget Character Forms · · Score: 1

    There is actually a distinction in Chinese between the written and spoken languages. Zhongwen, written Chinese, is largely the same everywhere. Hanyu, spoken Chinese, has many drastically different dialects.

  24. Re:Like there's never been a GAS STATION fire on Fire and Explosion At Hydrogen Station Near Rochester Airport · · Score: 1

    Just like how hydrogen stations blow up every day.

  25. Re:I hope they're smarter than the article writer on Low Energy Supercomputing · · Score: 1

    It's more like saying someone's mass is 686 N. You can guess the correct answer if you make a reasonable assumption, but the statement's wrong. (As a minor difference, the acceleration due to gravity is much less variable than the voltage supplied to electrical devices.)