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Comment Re:That old business partner I want to get back at (Score 1) 219

Don't forget to pour some fuel oil down the drain as a chaser.

You know, technically, you haven't committed any crime when you do that, have you. You didn't actually make any explosives, but it seems like if these sensors even worked at all, they would alert to this combination.

Comment Re:At what speed? (Score 1) 722

Well, there's one other factor you haven't thought of, apparently. More high school physics here. What happens if the cars, separated by 1 meter, DO collide.

With the distance so narrow, the relative velocity between the vehicles cannot become very high. (because the distance for acceleration is only 1 meter) The collision should do minimal damage, and then the collided 2-vehicle system should still keep decelerating because both vehicles still have brakes.

That's the theory, but I acknowledge that at highway speeds, it may not work out this cleanly.

Comment Re:At what speed? (Score 1) 722

This isn't how the math works. If the vehicle in front of you is applying maximum braking force, you can see it immediately - even if their rear bumper has moved on a few centimeters.

As for wireless communications : think of all the problems this introduces, versus having each car use their own sensor packages.

I'm not completely averse to the wireless idea, but I think the system should be designed to work reliably if wireless is jammed or hacked. It would not be difficult for someone to make a "troll lol lol stop" gadget that they could use to shutdown traffic at will if wireless worked the way you want it to.

Comment Re:At what speed? (Score 4, Insightful) 722

The first car cannot avoid the deer, true, but this condition will not cause a pileup.

Think about the physics. The inelastic collision between the deer and the car will marginally slow the front car down, true, but only slightly. (since a car weighs 2000 kgs and a deer weighs less than 100, for an estimate). So the combined car-deer vehicle will be going only slightly slower.

Ok, so now the car that is about to hit the deer applies maximum braking force. It begins to decelerate at a rate limited by friction between ground and car. This friction is independent of the mass of the car, for reasons I can't fit into here.

The moment it hits the brakes, the car behind it will see the distance between the two begin to decrease. They are "bumper to bumper", or within 1 meter of each other. The car behind will apply maximum braking force the very moment a single cycle of it's control loop happens (probably 1/1000 or a second or so).

The car behind that will do the same, and so on.

As long as no car in the pack has significantly better brakes than the other cars, no one will hit anyone. Even if a particular car does have better brakes, the collision will only do slight damage, as the relative velocities will be low.

Contrast this to what can happen in a real highway, where a car in front can have time to decelerate to a stop in some cases, and the cars behind may be driven by a distracted driver who does not see the stopped vehicle in time. The collision happens at highway speeds between the trailing car and the stopped car. This, in some cases, will be fatal.

Comment Problem is, most content struggles to do 1080p (Score 3, Interesting) 559

As it is right now, the only true 1080p content is high bitrate blu-ray disks, and PC games. There is nothing else.

None of the currently released consoles can render 1920x1080 at 60 fps : they use a lower frame rate (30 fps) and a lower rendering resolution (not even 720p internally for most games). The next gen can maybe do it, but I suspect that some games will use lower frame rates or internal resolutions so that they can put more detail into other things.

Broadcast channels, satellite channels, and HD cable channels all generally are full of lower bit-rate tradeoffs. You need about 30-50 mbps to do 1080p without compromises or visible encoding errors.

Maybe in another 10 years, when the technology is actually fully utilizing the 1080p displays we already have, will an upgrade make sense.

Note that this is for video content. For your computer or tablet PC, higher resolutions are useful, and shipping tablets are already at higher resolutions.

Comment Uh (Score 1, Interesting) 321

Isn't HFT just insider trading?

Insider trading = making stock trades using information that has not yet been disseminated to the open market.

HFT trading = using mathematical algorithms to detect the reaction of the open market to information, and to get ahead of it to make advantageous trades before the entire market can react.

Comment Re:Because we know? (Score 1) 452

Alice can say that all she wishes, but the judge will look at the signed immunity agreement and if he finds it to be adequate, will order Alice to the witness stand. (Alice's attorneys can of course delay things by objecting to the terms of the immunity agreement, but eventually it will be to the satisfaction of the judge)

If Alices refuses to spill, the judge then finds her in contempt and will jail her until she cries uncle, or about 10-15 years passes.

Comment Re:Because we know? (Score 1) 452

In this case, Alice is offered a signed immunity agreement if she testifies, exempting her from prosecution for any information she reveals on the witness stand.

After she is given immunity, she may no longer take the 5th as on paper there is no way she can be prosecuted.

Comment Won't the Syrians be able to get ready? (Score 1) 918

If the Syrian leadership knows that there's basically a 100% chance of a huge volley of missiles hitting them within a week, hasn't everyone already left and gone for cover?

Couldn't they fill the presidential palace or wherever their senior leadership is with rebel prisoners, just to knock out 2 birds with one stone?

Comment Solar Perhaps (Score 1, Interesting) 111

The only thing it's missing is a small solar panel to keep the battery charged. That way, no one has to climb those tanks of deadly radioactive water unless hardware has actually failed. Some of those Arduino boards already have battery chargers on them, but if not, a small regulated LiPo or NiCad battery charger is what you need. Then you just need a solar panel that is small and has the right output voltage. Sunelec.com seems to sell a 10 watt, 12 volt panel for $15. No big deal, and that's more than enough juice. Size the panel right, and you can do the monitoring continuously for a measurement every minute or so. (not that this really matters, but why not overdeliver?)

The Media

The Register: 4 Ways the Guardian Could Have Protected Snowden 233

Frosty Piss writes with this excerpt from The Register: "The Guardian's editor-in-chief Alan Rusbridger fears journalists – and, by extension, everyone – will be reduced to using pen and paper to avoid prying American and British spooks online. And his reporters must fly around the world to hold face-to-face meetings with sources ('Not good for the environment, but increasingly the only way to operate') because they believe all their internet and phone chatter will be eavesdropped on by the NSA and GCHQ. 'It would be highly unadvisable for any journalist to regard any electronic means of communication as safe,' he wrote. El Reg would like to save The Guardian a few bob, and reduce the jet-setting lefty paper's carbon footprint, by suggesting some handy tips – most of them based on the NSA's own guidance."

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