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Comment Re:drones (Score 1) 185

phallax ammo needs replenishing, lands somewhere perhaps in the costal town you are shooting over, and can't be run continuously. It cannot deal with non-lethal modes of attack (rubber dingy). it's very expensive. it has the problems of toxicity from DU. And most of all it's short range.

Comment other uses for lasers weapons as well. (Score 1) 185

there are other uses for lasers that projectile weapons don't satisfy easily.
http://www.army.mil/article/82...

there a high peak power, low total energy, laser ionizes a trail from the laser to the target device. then you send a bolt of lightning down that air column, which continues to ionize it while it electrically destroys the target. This can be used to disable vehicles non-lethally from remote distances. It can even be used to destroy roadside IEDs.

Another use, in fact the one it was originally researched for in the 1990s, is discharging lighting storms. In the 1990s there were multiple outages of the internet and other coms systems with astonishing price tags, due to lightning strikes. These don't seem to be as much of a problem now, at least not making the news. But at the time it looked like our new electronic infrastructure would need protecting.

ships are the ideal laser platform due to their abundant power and cooling, as well as their weight carring capacity, sturdy rigid platform, limited storage space for ordinance. Moreover ships are a highvalue asset that in recent years have been denied access to coastlines (littoral) due to proliferation of cheap anti-ship weapons. so defeating those is important to the navy. the main drawback with lasers is you can't fire them over the horizon, and thus the longer range weapon will always bee needed as well.

Comment drones (Score 1) 185

There never was a mission for the navy to shoot down nuclear missiles. there may have been a mission to shoot down anti-ship missiles. But they already had the Phalax and it is probably as effective as laser would ever be for that mission. But the drone situation changed everything. There wasn't a good way to deal with these, and the pinpoint accuracy of lasers combined with the low power requirements needed makes lasers the ideal weapon for this. Similarly, non-lethal weapons to fend off small craft boats are better solved by lasers than projectiles. Lasers are a great weapon for the navy since they have abundant power and cooling at hand. It means they can carry less explosives making their own vessels safer and reduces the logistics needed for re-supply.

What's remarkable to me is that in the 1970s the idea of a laser weapon seemed ludicrous since they deposited more energy into the laser than into the target, focusing through heated air was a problem, and simply rotating a large target (balistic missile) greatly increased the power needed to damage it. Now we have breakthroughs in laser diode efficieniency, and slow moving non-spinning targets with a low damage threshold

Comment Price to book? (Score 5, Insightful) 335

How is Q different than the usual Price-to-Book ratio, which formally has the same english definition of the share price to the per-share Asset value of the company? The price-to-book value doesn't go below 1 usually because a leveraged buyout of the company could fund it self by selling off the pieces. The Q-value seems to define assets as replacement value which is unclear. Is replacement value to be taken as what the assets would trade for in their used shape, or what they would cost to buy new.

Comment This cannot possibly be true (Score 1) 164

Well may be it can be true but it takes some explaining. The central problem I see is the crossection is smaller. SO how can it extract energy from wind that does not pass through its crossection? For that to be true then it implies that somehow the energy depleted wind is sucking energy from the surrounding windfeild as it passes by. I could imagine this is potentially possible. For example if you were to picture the wind like water piling up behind your hand in stream then it's the up stream water pushing on the water stopped in front of your hand that generates the force on your hand. So you are coupled to distant water. But the same is true of a regular windmill, and it has a larger crossection (hand). So it's not simple to work out how it manages to extract only 30% less energy per machine.

Comment Simple solution (Score 1) 152

All the password manager needs to do is take the name of the account want a password for, tack on the ow manager password, hash it. That's what it returns as the account password

There done. No need to check if you entered the right password for the manage. No need to even have a password management database. Or pay for anything since it's a one line perlscript. Since the ow manager has no clue if you entered their right password or not it won't give it away. One can think of embellishments to allow you to change your password

Comment Fault may not be the right measure. (Score 5, Funny) 408

One can be "in the right" and still not have done the right thing. For example, if the light is green I'm in the right not to slow down for the intersection. But that doesn't mean I shouldn't take precautions to check if someone is coming the other way. If I had I might have avoided the accident that was not assigned to my "fault".

On the other hand it's also possible that google cars will be better drivers than the average person. One might hope they use different CPUs for the texting and the driving.

Comment Re:no $8 (Score 2) 180

i'm curious how you reach that conclusion. it seems like as long as you plan on using hdmi the specs and price are comparable to an Rpi A which sells for $25. two differences are the wifi and built in storage which are extra on rpi. on the otherhand 4gb is kinda small if you want to call it PC the Rpi is supported better in hardware, software, drivers, and is proven. (how much is your time worth?) it looks to me like the shields for this consume the io pins as well.

http://slashdot.org/comments.p...

Comment no $8 (Score 1) 180

No 8 minute abs. You can't get abs in 7 minutes. Don't be rediculous.

Does that price include a power adapter, wifi adapter, and case? If so I might buy it an use those parts for my Rasberry Pi. If not then those will cost more than the "computer".

So this thing is basically a cheaper Rasberry PI without all the I/O features?

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