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User: The_Duck271

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  1. What about more complicated games on Lego Robot Plays Tetris · · Score: 1

    A bot to do this for a more complicated games like FPSs would be interesting. To play well would involve solving a number of AI/computer vision problems. The bot would have to pick out enemies from the image it was seeing, it would have to figure out where it was on the map from visual cues and determine where to go, and so on. It would be a simplification of the problem of creating a robot that can intelligently navigate its environment, with the actual physical robot abstracted away to "push the stick forward to run."

  2. Re:achievement porn on Baffled By the Obsession With Pretend-Business Games · · Score: 1

    What's the difference between "virtual" entertainment and "real" entertainment?

  3. Why the shortened links? on Considering Cheaper Pico-Projectors As Standard Equipment On Cell Phones · · Score: 1

    Why are all the links in this article to bit.ly shortened versions? I want to know what site I'm going to.

  4. Slower manipulation, faster thinking on Lego Robot Solves Any Rubik's Cube In 12 Seconds · · Score: 2, Interesting

    Mostly this is just a demonstration of how a computer can, from the initial scrambled state, immediately see clear through to a solution in a relatively short path, whereas humans can't visualize a whole solve instantly, and so they take it in steps, at a significant cost to solution length. Comparing the two videos you can see that the human is much faster than the robot at making sequences of turns, but must make many more moves than the robot.

  5. Re:Another game with no options on Dragon Age: Origins Expansion Coming In March · · Score: 1

    No; all the major quests can be resolved in at least two different ways depending on how you decide to play, with effects right up to the ending. And of course there are several endings depending on player choices.

  6. Open source "investigation" on Call To "Open Source" AIG Investigation · · Score: 2, Insightful

    You mean, like the open source "investigation" of the leaked climate change research group emails? That turned out well...

  7. Re:Using satellite imagery on Find DARPA's Balloons, Win $40K · · Score: 1

    Hmm. Looking at those sample images suggests to me that it's impossible to do something like this with satellite imagery. No one could write a program to distinguish ten red balloons from the tens of millions of red cars in the US.

  8. BattleMaster rocks on Linux Games For Non-Gamers? · · Score: 1

    I'd just like to put in that BattleMaster, the game cited in the summary, is awesome. I don't play it now, but I played it for four years or so and it's excellent. It's an amazing long-term game that mixes strategy, politics, and medieval roleplaying. You're always on a team (a realm of nobles), and you're usually at war. Wars are intricate affairs lasting months and punctuated by battles every few days. Realms can be created and destroyed, and the politics of a continent will slowly shift over the years as territory changes and hand and alliances are formed and broken. For those that are into it, there is real role-playing--that is, story-telling not directly related to game strategy, unlike pretty much all so-called massively multiplayer online "role-playing" games, where the world has a story but you wouldn't know it from the way players act and talk. In BattleMaster, people act like nobles, and one actually feels immersed in a real feudal society. As the summary suggests, it needn't consume much of your time (10 or 20 minutes a day will cover you), but if you get into it it can entertain you for much longer. I hope this mention on /. gets a few people into BM.

  9. Re:Interesting job title on Nissan Gives Electric Cars Blade Runner Audio Effect · · Score: 1

    Engineer sounds, duh.

  10. Re:Won't people just tune it out? on Nissan Gives Electric Cars Blade Runner Audio Effect · · Score: 1

    Do you tune out the whir of a car coming towards you while you're crossing the street? That's what this is about.

  11. Interferometry generates lots of data on SKA Telescope To Provide a Billion PCs Worth of Processing · · Score: 4, Informative

    Some people might be interested in knowing where all this data comes from. There's a rule of thumb in astronomy that the angular resolution of your images is the wavelength of the radiation you're receive divided by the diameter of your telescope. Radio wavelengths are pretty long (up to tens of meters), so you need really big telescopes, which you get by scattering lots of little telescopes all over the place and then looking at the how the phase of the incoming radiation shifts based on location. So what you do is you sample the voltage of each antenna with 1 or 2 bits of resolution at the Nyquist frequency. So for 100Mhz radio waves you sample at 200MHz. That's 50MB/s for a single antenna. The SKA will likely have tens of thousands of little antennas scattered all over the place. So say 50MB/s times 20,000 antennas = 1TB/s = 100 petabytes/day, which is about what the summary says.

    Now, it's not quite as bad as it looks. You don't have to pipe all this data to a central point to analyze it. You can take a small group of antennas and just look at the correlations between those, combine the data from that group and send the combined data to a second level of correlators, which takes data from a set of small groups, and so on, in a hierarchical fashion. You lose some information this way, but you get most of it, and the only wa to get all the information out of the data would be to bring it all to a central processing location so that data from all antennas could be compared to that of all other antennas, which is O(N^2) in the number of antennas and obviously infeasible for a telescope like the SKA. Even as it is, the system of hierarchical data collection is really pushing Moore's law, as the article shows.

  12. Re:Speaking as a chemist on Most Detailed Photos of an Atom Yet · · Score: 2, Informative

    The z-axis is arbitrary; you just pick some direction and call it the z direction.

  13. Re:How would this look animated and slowed down? on Most Detailed Photos of an Atom Yet · · Score: 1

    The "nucleus with balls spinning around it" is a significantly oversimplified statement of the true quantum weirdness that goes on in atoms.
    See here and responses.

  14. Re:Speaking as a chemist on Most Detailed Photos of an Atom Yet · · Score: 5, Informative
    At atomic scales electrons cannot be thought of as points; instead they are smeared out probability distributions. They don't exist at any given point, there's a chance for a given electron to be found throughout a whole region of space, and the probability of finding it at any given point is given by a probability distribution. These probability distributions are called wave functions, and given an electron's wave function you can calculate the likelihood of getting different results when you take a measurement of the electron. It is a strange aspect of quantum mechanics that you can't calculate exactly what you will measure, you can only establish the probabilities of each possible outcome.

    Another aspect of quantum mechanics is that if you measure, say, the energy of an electron in an atom, you can only get one of a certain set of discrete values, and never any energy in between those values. The energy of the electron is quantized. In general, if you measure an electron's energy you have a certain probability to get a result corresponding to the first energy level, a probability to find it in the second energy level, and so on. This is also the case for some other things you can measure, like angular momentum.

    However, there are certain wave functions that correspond to exactly one value of energy; that is, if you have an electron with this wave function, you are guaranteed to get a certain energy value when you measure it. In fact, there is a special set of wave functions with the following three properties:
    • They each have a definite energy level.
    • They each have a definite total angular momentum around the nucleus.
    • They each have a definite angular momentum around the z axis.

    These wave functions are the atomic orbitals that are so important in chemistry. If you calculate the shapes of the wave functions that satisfy these properties, you get the shapes shown on the Wikipedia page. They are listed in a table indexed by the variables n, l, and m. n corresponds to the energy level, l corresponds to the total angular momentum, and m corresponds to the angular momentum around the z axis. For example, you can see that orbitals with high m (angular momentum around the z axis), like the ones on the very right of the Wikipedia table, are sort of flattened out by the centrifugal force from spinning fast around a vertical axis.

  15. "The good old days" on How To Make Science Popular Again? · · Score: 1

    Whenever I see things like this I can't help but wonder if people aren't succumbing to the common assertion that things (scientific literacy, societal values, quality of education, etc.) used to be good, but things started going down hill this generation. Without some kind of supporting evidence my default position is to be very skeptical of this kind of assertion. What evidence shows that scientific literacy is going downhill?

  16. Re:Safety? on Students Take Pictures From Space On $150 Budget · · Score: 1

    Human heads cover quite a small percentage of the earth's surface; it would be rather remarkable if the balloon hit a person.

  17. More like http://r337arts.com! on Students Take Pictures From Space On $150 Budget · · Score: 1

    Anyway, pretty neat. I thought at first they were talking about a rocket, which I thought must cost much more than $150 to get 20 miles up. But I guess a balloon gets you much higher for much cheaper. Not as cool as a rocket though. I think really big amateur rocket launches go about 10 miles up? There are some impressive videos on youtube.

  18. Re:Private Car Cameras on Trust an Insurance Company's "Drive-Cam?" · · Score: 1

    If it proved predictive, yes. If not, no.

  19. Re:Private Car Cameras on Trust an Insurance Company's "Drive-Cam?" · · Score: 1

    There is such a thing as chance correlation, even in a complete absence of any causation at all. That is the point of the aphorism.

    No, that's not the point. Of course if your standards for statistical significance are low enough you will find all sorts of nonsense "correlations." That is not the point. The point is that while there is a very strong correlation between the income of Massachusetts pastors and the price of rum, the pastors are neither financing the rum trade nor profiting off it.

  20. Re:Misleading on Bacteria Used To Make Radioactive Metals Inert · · Score: 1

    "Inert" has absolutely nothing whatever to do with radioactivity, even though radioactive materials may or may not be inert.

    Then the title should have been "Bacteria Used to Make Toxic Metals Inert."

  21. Re:That Analogy Falls Apart on Sending Astronauts On a One-Way Trip To Mars · · Score: 1

    Why do people voluntarily join the military? Some people are willing to die for a cause. Whether that disqualifies them from being sane is subjective, but if you say that no sane person would volunteer for a Mars trip it seems to me that you are also implying that no sane person would join the army.

  22. Pretty cool on Pigeon Protocol Finds a Practical Purpose · · Score: 2, Insightful

    I don't know why everyone needs to find something to whine about in this article; it's a pretty cool story. An amusing blend of modern and ancient technology to solve an interesting problem.

  23. Re:I knew it. on Entanglement Could Be a Deterministic Phenomenon · · Score: 1

    [citation needed]

  24. Pi should be 2 pi on Pi Calculated To Record 2.5 Trillion Digits · · Score: 4, Interesting

    There's a good argument that the choice of pi = (circumference / diameter) was unfortunate; it should have been (circumference / radius). In the light of modern mathematics it seems clear that the radius is more "fundamental" than the diameter; choosing pi = (circumference / radius) = 6.28... gives a number of nice things like:
    A = (1/2)pi r^2, just as E = (1/2)m v^2 or d = (1/2)a t^2, and for the same reason.
    In general, in the current convention, 2pi seems to show up a lot more than pi, e.g. there are 2pi radians in a circle, sin(x) has period 2pi, etc. All these would become simply pi with the (circumference / radius) convention

  25. Re:Rational PI FYI on Pi Calculated To Record 2.5 Trillion Digits · · Score: 1

    I don't think this is true. From what I've read, the ancient approximations for pi were 22/7 or 25/8. The surprisingly accurate approximate 355/113 wasn't found until 400 AD according to wikipedia. And anyway, we don't gain anything from the fact that 360 is close to the numerator of a rational approximation to pi, so this is even less likely to be the reason for using 360. I guess it helps you remember that the length of the circular arc subtended by one degree is a little less than 1/113th the diameter, but this is a fairly useless fact.