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User: harrkev

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  1. Re:Creepy on DARPA Successfully Demonstrates Self-Guiding Bullets · · Score: 1

    I don't think the materials science is there to deal with forming/deforming a projectile on the order of 300,000 rpm (presuming a 1:7 twist & 3,000 fps).

    Piezo actuators should have no problems working at up high tens of KHz, and even up in the hundreds. Peizo elements are used in tweeters, where they have to react up to at least 20 KHz, in the right range for this project. Piezos do not have much distance that they can travel, but at that speed, you might not need much distance. All you really need is a little paddle that can stick out an slow the bullet down on one side.

  2. Re:Alternate use for this technology on DARPA Successfully Demonstrates Self-Guiding Bullets · · Score: 1

    And here's a clue for you. NO one over there wants peace at all, ever.

    Sorry, but many Muslims are taught to hate Jews from a very young age:
    https://en.wikipedia.org/wiki/...

    There are other examples, but this is the most famous one that I could think of.

    From what I understand (and I know many American Jews who have visited Israel), the Jews pretty much just want to be left alone.

  3. Re:Creepy on DARPA Successfully Demonstrates Self-Guiding Bullets · · Score: 2

    You got it. Lasers are cheap... electronics are cheap... batteries are cheap... spoofing is cheap.

    Really, as an engineer, I can imagine two ways for this thing to work, and it depends on if the projectile spins. Typically, bullets spin so that they act as gyroscopes -- always pointing the same direction (YouTube has videos of guys firing pistols into ice -- ice stops bullet which just sits there and spins like a top).

    If the projectile spins, you can, in theory, guide it with a single fin that can extend or retract. You could not use a standard camera as such, because you are spinning wildly. Assume 2000 FPS bullets -- if you want to shoot a mile, you need at least this much. Also assume a 1-in-12 twist (real twists are in the range of 1-in-7 to 1-in-14, depending on shape and weights of bullet). That means that the bullet is spinning with a approximate rotation of 2 KHz. I doubt that you could have an effective regular camera spinning like that and still work. A better way would be to have a linear sensor (a line camera) that looks forward and to the side. This could operate. When you see a bright stop, see how far it is from the center. More off-center = kick your fin a bit more. This is simple and straightforward. However, since the bullet is spinning and you do not know when the camera will cross the laser, you probably need to keep the laser on full time. This is probably the easiest and cheapest way to accomplish this, but should be easily spoofed. You could maybe put a crypto on the laser signal by changing the intensity of the signal without turning it off, but it would have to be a much lower frequency than 2 KHz because that is your effective sample rate. If you assume 500 Hz signal (four-times oversampling), you would only get about 500 bits of data before you hit your target (assuming a target 2000 feet away). Is that enough to actually apply crypto? I am not sure...

    On the other hand, if the bullet is NOT spinning, you can use a regular camera and regular fins to control it. In that case, it is entirely reasonable to embed some sort of cryptographic modulation on the signal. In any case, the existence of a 2-D sensor makes the bullet more expensive, and increases the amount of processing that needs to be done. It should, however, be more feasible to put crypto, but at greater cost.

  4. Re:Alternate use for this technology on DARPA Successfully Demonstrates Self-Guiding Bullets · · Score: 3, Insightful

    I don't get the US. I mean, by now you should have noticed that the bigger and more complicated the technology, the more you play into your opponent's hands. First of all, you're using high tech weapons in a low tech war. You can't really fire any round anymore that doesn't cost you more than what your target cost your enemy.

    Off topic, I admit, but this reminds me of the current Isreal/Hamaas conflict. Just launch simple, dumb, and cheap unguided rockets from the Gaza Strip. Isreal has an "Iron Dome" defense system that is supposedly pretty effective at stopping them -- at $1,000,000 per shot. Great way to bankrupt an enemy...

  5. Re:Creepy on DARPA Successfully Demonstrates Self-Guiding Bullets · · Score: 1, Interesting

    Actually, this should not be scary at all! You just need to figure out the frequency and modulation of the laser used. Then, just make sure that you have such a laser pointed at the guy beside you. You are suddenly safe from snipers! Just make sure that you do not like the guy beside you.

    Seriously, the only way this could be spoof-proof is to modulate the laser with some type of crypto.

  6. Re:Why 80% on William Binney: NSA Records and Stores 80% of All US Audio Calls · · Score: 1

    Hey, Obama promised "Hope and Change." Isn't that what we have here? Admittedly, Bush started this -- probably. Or maybe he inherited the seeds from Clinton or earlier -- who knows how far back this trail goes? But Obama has had almost 6 years to fix things. Instead, under his watch, things have gotten worse.

    In Obama's defense, I do not know if Romney would have done things any differently, but I suspect we would probably still be here even if he had won.

  7. Re:another tesla fire on The First Person Ever To Die In a Tesla Is a Guy Who Stole One · · Score: 1

    And how many cars do you think are completely safe from fire after a 100 MPH collision?

    This does nothing to tarnish the safety of a Tesla, in my mind. I still would not buy one, but mostly because I can't afford it.

  8. Re:USB DACs on Ode To Sound Blaster: Are Discrete Audio Cards Still Worth the Investment? · · Score: 5, Interesting

    A USB audio interface also lies outside the electrically noisy interior of a PC chassis.

    Strong caution with USB audio. There is a metric buttload of cheap USB adapters, While they technically work, they typically lack analog filtering that gets rid of higher harmonics. If you look at the output on an oscilloscope, instead of a smooth wave, you see the actual steps. Better audio hardware should have filters to smooth this stuff out.

    Another MAJOR thing is inducing noise into the output. This is not just for USB cards, but all audio solutions. You need some pretty good filtering between the digital and analog power domains -- yet another area where cheap sound can skimp. Hey, let's shave $0.05 off by dropping this capacitor and inductor!

    The original article really touches on two separate areas:
    1) Audio processing
    2) Higher quality audio circuitry

    SoundBlaster (and other gaming-oriented cards) typically do both. However, do you really NEED both? The audio processing stuff is supposed to provide an API that games can use to make thing sound more realistic, or offload audio processing from software to hardware, or both. It can typically decode various dolby flavors, and do some other fancy DSP-ish type stuff. Do you really NEED all of that? If so, then maybe a gaming card is for you.

    However, what if you want the best sound possible, the lowest noise possible, and don't really game or use the various audio enhancements? You just want a plain-vanilla sound card, but with the highest quality audio. Where to do? Skip the computer store, but go to your local MUSIC store (not the ones that sell CD's, the ones that sell GUITARS). Those cards skip all of the DSP bells and whistles, but have the best-quality DACs and filtering that you can find. You can find some really good USB solutions that will blow on-board audio out of the water for about $100 or so. Of course, you can go crazy and spend $500 or more if you want. If it is good enough for a music producer to use in a studio (who makes his or her living off of the sound), it is probably good enough for YOUR music and movies.

  9. Re:Unions. on Interviews: Ask Lawrence Lessig About His Mayday PAC · · Score: 2

    In union there is strength, a lesson the geek never seems to learn. How else do you suppose a day laborer can out-match the billionaire in politics?

    Yes, and "union" is nearly as useful as "struct."

    Geek humor aside, I am not actually against unions, but I am against making union membership mandatory. In an ideal world, labor vs. management would be a perfect balance. However, bad things happen when one side gets more power over the other. If management is too powerful, poor working conditions and poor wages may result. If unions become too powerful, then the actual competitiveness of the company can be impacted.

    True story:

    I used to work for a company who is currently known for making a cell phone spy tower named after a flat marine animal. This was well over a decade ago. I had helped design an electronic module used to help test a fighter aircraft. I debugged this card. I touched it, hooked it up to test equipment, had test wires soldered to it, and had an intimate understanding of how it functioned.

    Fast forward to when the cards are debugged, so I help deliver this stuff to the customer (big airplane company in Seattle). The technicians were all unionized, which is fine. However, as a part of the union contract, the engineers were not even allowed to TOUCH the equipment. So, I handled this stuff extensively back in Florida, but suddenly I am not allowed to even plug in a cable in Washington. This means that working extra hours to get the job done was NOT an option, since the tech was not approved for overtime.

    Sorry, but that SUCKED! Tech deserve to be paid fairly, and they are cheaper than engineers, so it makes sense to use them when they can do the job. But, to say that engineers cannot even touch the equipment that they design is completely asinine, and it means that even if the test setup only needs to be changed every hour or two, the company still needed to pay a technician to be there (extra money), or you have to wait for one to show up (slowing down testing). That is the kind of crap that leaves a bad taste in my mouth when it comes to unions. Fair pay and benefits are one thing. Aggressively protecting your job function to the detriment of the company is another.

    Should I even mention the union rules that I have broken by moving my own computer and changing the height of my own cube tables? I am sure that I am going to hell for that one.

  10. Re:Unions. on Interviews: Ask Lawrence Lessig About His Mayday PAC · · Score: 1

    By the way: better description here:

    http://en.wikipedia.org/wiki/U...

    Basically, you can't be forced to do things like attend meetings, vote, etc. But you CAN be forced to pay dues or loose your job.

  11. Re:Unions. on Interviews: Ask Lawrence Lessig About His Mayday PAC · · Score: 1

    There are many "right to work" states where you do not HAVE to join a union. Here are lists of them:

    http://en.wikipedia.org/wiki/R...
    http://www.nrtw.org/rtws.htm

    If they are not "right to work" then you can assume that you are forced to join a union to get a unionized job.

  12. Unions. on Interviews: Ask Lawrence Lessig About His Mayday PAC · · Score: 5, Insightful

    I was just wondering if you were also concerned about money from unions? To me, a millionaire donating is own money is somehow less problematic than unions taking money from their members to donate. Keep in mind that in many states, union membership is required in order to get the job. Therefore, many union members may find their money being used to support candidates that they do not support.

  13. Re:This will hugely backfire... on FWD.us: GOP Voters To Be Targeted By Data Scientists · · Score: 2

    I agree with this completely. I am a rather moderate conservative. And I am against illegal immigration.

    Hypothetical question. You are the ruler of a country and you want to have more citizens. Who do you choose to offer citizenship to:

    1) Person who goes to an embassy, fills out the required paperwork, and tried to do things the right way.

    2) Person who decides that they want in, and ignores the law and smuggles themselves in, making their first act in the country breaking the law.

    To me, it seem that #1 has already proven that they can obey the law, while #2 has already proven that they do not mind breaking it.

    I must admit that I do have a lot of sympathy for youths who were brought over here with their parents. They did not have much choice in the matter. If there is anyone deserving of amnesty, it is this class. However, the parents should return to where they came from, and fill out the proper paperwork to return here.

  14. Re:Available in Amazon UK on Amazon Dispute Now Making Movies Harder To Order · · Score: 4, Funny

    It is listed at 10 pounds.

    Wow. Shipping for that DVD must be VERY expensive. They are only an ounce or two here in the USA.

  15. Re:It's not really a myth anymore on The Sci-Fi Myth of Killer Machines · · Score: 4, Interesting

    The problem is not who controls the strings, it is what happens when the strings are no longer needed.

    A.I. will present little danger (except A.I. the movie, which is so bad it ought to be banned as a WMD) as long as a human can pull the plug. Two decades ago, the Internet was a novelty. Now, the economic consequences would be catastrophic if the Internet suddenly went dark. Similarly if/when A.I. actually arrives, it will be useful and helpful. It will become more and more critical such that a decade or two after it arrives, the act of unplugging it would have catastrophic consequences. So, if Skynet goes bad, then bad things will happen whether you unplug it or not.

    To me, what it all comes down to is will. Can an artificial personality actually have a will? Can it become afraid of its own demise? Even if it is theoretically possible, can our researchers and programmers achieve it? Will it be able to reach outside its own programming and decide to eliminate humans? Maybe, maybe not.

    On the other hand, once A.I. becomes common, can a rogue state task the A.I. with eliminating all humans on a certain continent? Almost certainly. What happens then is simply a battle of A.I. agents. Who can outsmart the other?

    Just my opinion, and worth every penny that you paid for it.

  16. Re:I routinely get new 550MB/s 120GB SSDs for $60 on Crucial Launches MX100 SSD At Well Under 50 Cents Per GiB · · Score: 1

    Kingston 480G is $250 right now on the Egg. The 512G crucial is $225.

    Sorry, but the Crucial drives have good reviews from the hardware sites, and are actually quite cheap for the capacity. 1/2 terrabyte of solid state for well under $250? Yes, please.

  17. Re:A boon for CAD, hopefully on 4K Displays Ready For Prime Time · · Score: 2

    I often work on fancy PCB designs and can always use more resolution and a bigger screen, within limits. There's no point in having a screen so wide that my head is always moving like at a tennis match.

    But more resolution makes editing quicker and easier.

    Bah. You PC board wusses. Try doing physical design on a custom ASIC (note my sig).

    More pixels definitely helps. I have been using a 30" 2560x1600 (Dell for about $1200), but more pixels for half the money seems like a great deal! The down side is less glass itself, so the pixels are smaller. My old eyes would probably have a hard time staring at text at that resolution. Yes, I know that I can change fonts, but I am a strong believer in more monitors in general. You can have the layout on the big glass, and terminal and/or EMACS windows on the side monitors. Now THAT is a productivity boost. The problem is that with your side monitors having a significantly different pixel density from the main monitor make having an ideal font size impossible. Either too big on the side monitors or too small on the big, central monitor.

  18. Re:What! on TrueCrypt Website Says To Switch To BitLocker · · Score: 2

    So, assuming that this IS real, any suggestions on FOSS encryption for those without access to BitLocker?

    On a side-note, how could TrueCrypt be actually broken? Even if the encryption is broken, that can be fixed in a later release. There is a LOT of stuff in TC (boot manager, GUI, etc.), and you cannot tell me that ALL of it is bad.

  19. Re:What the f*$# is wrong with us? on Misogyny, Entitlement, and Nerds · · Score: 3, Insightful

    The best trolls are indistinguishable from serious comments.

    No, not trolling. Sorry, but there IS a grain of truth in geek misogyny. This toon is a humorous example:

    http://www.geeksaresexy.net/20...

    Also, when was the last time that you saw a woman depicted in a video game that was less than a "C" cup? Sorry, but if you were to go back a few centuries and give a woman a sword and armor, I am pretty sure that the armor would cover more than about six square inches of her body. Sorry, but in video games, women are sex objects (Metroid is the one notable exception that I can think of). Even as protagonists, they will dress scantily, while standing next to a male character that is so covered in so much armor that you can only see his eyes.

    Perhaps part of it is that women are, in general, under-represented in geek culture. Guys are attracted to girls, but there are damn few of them floating around in geek circles. So, they go from being "people" to becoming something closer to a "trophy."

  20. Re:Good luck on that... he won't appear on Iran Court Summons Mark Zuckerberg For Facebook Privacy Violations · · Score: 4, Interesting

    Which is sad because the country has quite a bit of history

    It really is a shame. That part of the world used to be known for arts, sciences, and education. I wish that it were still that way...

    en.wikipedia.org/wiki/Achaemenid_Empire

  21. Re:Killowatts are power, not energy on The Brakes That Stop a 1,000 MPH Bloodhound SSC · · Score: 0

    At hundreds of miles per hour, the car aerodynamics would probably be closer to an aircraft. Why not use some sort of air brake -- little flaps that stick out causing wind resistance? Once you get down to, say, 300 MPH, there are certainly commercial car brakes that can handle that -- NASCAR does it every day.

  22. Re:No 3D printing? on A 32-bit Development System For $2 · · Score: 1

    FYI: Atmel does have ARM processors too, along with all the usual goodies (ADC, DAC, timers, UARTs, etc.). Prices for their ARM stuff starts below $2.00 also.

    However, the one thing that Atmel does *NOT* have is a DIP package, which, IMHO, is kind of a big deal. A dip package is probably one of the best things that you can do to be hobbyist-friendly. The other things that hobbyists like are a free tool chain and a low-cost programmer. Atmel does those OK.

    Disclaimer: I work for Atmel.

  23. Re:Cue "freedom" NRA nuts in 3.. 2.. 1... on First Arrest In Japan For 3D-Printed Guns · · Score: 1

    It is also possible that people use guns to defend themselves.

    Australia really cracked down on gun ownership back in the 1980's. Since then, murder went down a little, but violent crime in general went up by 40%. For each person NOT murdered, over six hundred additional people are a victim of violent crime...

    Yet gun deaths went way down, so I am sure that a lot of people trumpeted success. Too bad that stabbing and beating deaths made up most of the difference.

  24. Re:Cue "freedom" NRA nuts in 3.. 2.. 1... on First Arrest In Japan For 3D-Printed Guns · · Score: 1

    Because guns don't kill people. People with guns kill people.

    Interesting how you think that the link you shared somehow means something. In Russia, guns in civilian hands are VERY scarce, yet the murder rate as a whole is rather higher than it is in the US.

    Well, I suppose it makes sense if every gun death is a tragedy, but if somebody is stabbed or beaten to death, it is no big deal.

    Clue for you: a person stabbed to death is just as dead as somebody shot to death. But I suppose that does not fit in with your agenda, so you happily ignore that fact.

  25. Re:Gun nuts on "Smart" Gun Seller Gets the Wrong Kind of Online Attention · · Score: 1

    Ah yes. The famous "gun deaths" myth. Let me use a simple analogy (apparently I will have to keep it simple so that you can follow along).

    Suppose that you have a relative that was run over by a red car. So, you go on a "red car" crusade and manage to make red an illegal color for cars. Soon, the number of deaths due to red cars plummets to zero, so you loudly trumpet success. You did, in fact, eliminate deaths due to red cars, but is anybody really any safer?

    I feel that it is necessary to point out what is obvious to most people: somebody shot to death is just as dead as somebody stabbed or beaten to death with a club. In fact, if I had to choose, I would rather be shot dead instead of bludgeoned to death.

    Russia has far fewer gun deaths due to the fact that civilian guns are very scarce, yet their murder rate is much higher than ours. Would you prefer that our crime statistics were more in line with Russia?

    Now, if you want to talk overall violent crime rate and murder rate, that is fair game. Australia make gun ownership MUCH harder a few decades ago. The end result is that their murder rate, which was already rather low, went down a little. However, overall violent crime increased by 40%. I calculated that for each person NOT murdered that the tradeoff is that approximately 660 additional people were the victims of robery, assault, or sexual assault. Yes, 660. That is NOT a typo. I used data from the Australian government and adjusted for population. Gun deaths did indeed go down, but stabbings went up, making up most of the difference.