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Comment: Re:Creepy (Score 2) 96

by harrkev (#47434677) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

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.

Comment: Re:Alternate use for this technology (Score 3, Insightful) 96

by harrkev (#47434367) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

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...

Comment: Re:Creepy (Score 2) 96

by harrkev (#47434329) Attached to: DARPA Successfully Demonstrates Self-Guiding Bullets

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.

Comment: Re:Why 80% (Score 1) 186

by harrkev (#47433621) Attached to: William Binney: NSA Records and Stores 80% of All US Audio Calls

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.

Privacy

William Binney: NSA Records and Stores 80% of All US Audio Calls 186

Posted by Soulskill
from the must-use-a-good-compression-algorithm dept.
stephendavion sends a report at The Guardian about remarks from whistleblower William Binney, who left the NSA after its move toward overreaching surveillance following the September 11th attacks. Binney says, "At least 80% of all audio calls, not just metadata, are recorded and stored in the U.S. The NSA lies about what it stores." He added, "The ultimate goal of the NSA is total population control, but I’m a little optimistic with some recent Supreme Court decisions, such as law enforcement mostly now needing a warrant before searching a smartphone." One of Binney's biggest concerns about government-led surveillance is its lack of oversight: "The FISA court has only the government’s point of view. There are no other views for the judges to consider. There have been at least 15-20 trillion constitutional violations for U.S. domestic audiences and you can double that globally."

Comment: Re:USB DACs (Score 5, Interesting) 449

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.

Comment: Re:Not new (Score 1) 253

by BVis (#47414169) Attached to: US Tech Firms Recruiting High Schoolers (And Younger)

You can get the education cheaper than that; use a state college or university

Not really, not anymore. The in-state cost (not tuition, that's a very small part of the actual cost) of my state's public university exceeds $20,000 per year. While that is less than the $40,000 that "elite" private institutions get, I wouldn't describe it as "cheap". Plus, that degree from that "aggie"/"safety" school is waaaaay less marketable than the equivalent degree from Harvard etc., even though the quality of the actual education from the state institution is reasonably equivalent.

get a part time job instead of all debt

Let's do the math on that one. Say you can find a part-time job that pays you $12 an hour (not bloody likely). If you were to work 40 hours a week, 52 weeks a year, you'd make about $25k before statutory deductions, so let's say you take home $20k. That'd pay for a years' bills at an in-state university; however, since you're actually going to school, you can work probably 20 hours a week when classes are in session if you work your ass off. At my school, classes were in session for all but 16 weeks out of the year. So, 16 * 40 * $12 = $7680, and 36 * 20 * $12 = $8640. That's $16320 before deductions, so probably about $13k take-home. That won't pay your way through any four-year college that I know, and that number is likely the high limit of a reasonable probable range. You could go to community college for that much; just don't get your degree from there, it's a waste of money. No matter which way you look at it, you're talking probably close to $10,000 a year in loans to make up the gap under ideal circumstances (I'm counting incidental expenses as well, like books and meals the cafeteria plan doesn't cover.)

get used books or borrow a friend's

Used books aren't cheap either. It's changing with pirated PDF versions of the texts, which are free, but if you want the actual book, even a used copy will set you back $100 or so depending on subject. And that's if you can get a used copy of the specified text; they love to put out new "editions" every year that eliminate any used books from the market. This is especially bad with professors that make you buy the book they wrote, you're a captive audience and they want that cheddar.

Comment: Re: Not new (Score 1) 253

by BVis (#47414057) Attached to: US Tech Firms Recruiting High Schoolers (And Younger)

Furthermore, you should not be going to college/university for money.

Bullshit. College has become an investment in your future earning potential; it's all about the money. Whether it's a good investment or not depends on a large number of factors, such as your chosen career path and the bullshit "reputation" that your chosen school has. It's become far too expensive to go to college for a "well rounded" education, or for a good general basis for further study without actually doing that further study (masters, doctorate, etc). Nobody gives a fuck if you did well in Rocks for Jocks or waxed eloquent in your Comp Lit class; they care that you spent a lot of money on your education so that they can treat you like crap without your quitting, due to your enormous student loan payments.

Comment: Re:Dirty power (Score 1) 199

by Pharmboy (#47411463) Attached to: My most recent energy-saving bulbs last ...

Generally speaking, anything with lots of parts has more points of failures. Since CFLs all have ballasts, my experience has been that spikes does take a toll, by virtue of them dying after the storm.an incandescent is just a big resister. Yes, it can break but it is fairly tolerant by virtue of being tungsten and having no other parts. This is why I spend the money for the better CFLs. I've been using CFLs for well over a decade now. Been using them since the 90s, so not an expert, but I've owned a lot of them.

Comment: Re: Two sides to every issue (Score 1) 401

by BVis (#47399821) Attached to: No Shortage In Tech Workers, Advocacy Groups Say

And even the first kind of companies is restricted by the prevailing wage law, so they pay quite a good wage as a result.

No they don't. They don't because the H1Bs don't complain about it (because complainers get fired, especially when they complain to someone who's in a position to cause the business trouble), so there's little chance they'll get caught. Even if they do complain, good luck finding out what the "native" workers actually get paid; that information is usually confidential.

Comment: Re:Non-compete agreements are BS. (Score 1) 272

by BVis (#47375051) Attached to: Amazon Sues After Ex-Worker Takes Google Job

You were talking about yourself ("I can replace my job in 1/10th the time/cost it would take my employer to replace me."), then you made a value judgement against others ("If you are at your employers mercy, you have no one to blame but yourself.") Attacking your value judgement and your privilege is reasonable in that context.

We all like praise, but a hike in our pay is the best kind of ways.

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