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Comment: Re:Kessler syndrome is the real worry (Score 1) 165

by pyalot (#43572957) Attached to: Space Junk 'Cleaning' Missions Urgently Needed
Kessler took into account that collisions are unlikely and that they won't produce the same kind of debris. And both don't matter to the outcome for some statistically unintuitive reasons. When two objects collide, there will be an increase in debris. It might only be a few crumbs, or it might be a spectacular cloud of new debris, it doesn't matter. What matters is that the outcome of the collision increased the likelyhood of further collsisions in the whole system. This is known as a runaway feedback loop, and traditional statistics don't tell you much about how these go. The reason is that they're unstable, chaotic systems, much like the weather. Statistics can't tell you next weeks weather because it can't model chaotic systems. Chaotic systems that include feedback have a particularly nasty habit of "tipping over". That is, they look normal and noncritical right up to the point where they become wild runaway feedback loops. Two objects colliding have a separating velocity, and for certain, their separating velocity (and energy) after collision is reduced. However that does not mean that the energy is reduced for the whole system much. For a third object (subject to a later collision) is not affected by the change of energy in the previous system. The amount of energy removed from the entire system is proportional to the fraction of energy that one collision of two objects represents. I.e. every collision only removes a very tiny fraction of energy from the system.

Comment: Kessler Syndrome - feedback runaway space debris (Score 1) 165

by pyalot (#43570059) Attached to: Space Junk 'Cleaning' Missions Urgently Needed
It's theorized that this is a possibility where collisions between space debris produce more debris and rise the likelyhood of further collisions. This would lead to a rapid feedback loop as collisions cascade. This would likely render space travel impossible for the next couple thousand years. http://en.wikipedia.org/wiki/Kessler_syndrome

Comment: I used to work for DWS/PacketVideo (Score 3, Interesting) 151

by pyalot (#36918790) Attached to: Spotify Sued For Patent Infringement
As anybody can see from my CV ( http://codeflow.org/ ) I used to work for DWS. This was a little serverside company sister to Secure Digitial Container, the company the patent comes from that was later bought (together with DWS) by PacketVideo.

I liked working for DWS, they where a small and quirky company with good people. DWS/SDC never sued anybody for this patent, it was mainly a bargaining chip to impress clients. Mind the patent is about DRM, specifically, it's about polymorphic DRM (that is the variant that delivers its own encryption/decryption/obfuscation code together with the content).

Sidenote: DWS/SDC where far flung leftovers of Napster.

But then the inevitable happened, the companies got bought by PacketVideo. The founder/investor and the then CEO (a superb business drummer, though no techie) left the company and American management took over.

During my work there, I was increasingly troubled by the DRM side of business. Eventually I left (and I'd have probably been fired if I didn't), mostly for reasons where management differed with my idea of efficiency and quality. I traveled around the world and I started freelancing, and I can't say it was a bad decision, has been a good life since.

I'm not surprised that PacketVideo eventually started suing people for the patents they hold. It's a small and troubled company that's been struggling for years to "get it right", and as they probably increasingly run out of funds to keep the fiction alive, it gets ever more tempting to cash in some quick buck simply by virtue of sitting on patents you've acquired.

Comment: Re:Patently useless (Score 1) 309

by pyalot (#35773864) Attached to: US Navy Close To On-Ship Laser Cannons
Geeze you're clueless. It doesn't matter if you're powering a flywheel or charging a more conventional capacitator. After you discharge that thing, the energy's gone, and you have to put new energy in. The usual way to use it is to accumulate energy into it over a longer time, in order to quickly discharge it. You usually do that if you have an energy application that requires more power then you can produce in-situ per unit of time. The reagan star-wars programme had at least the advantage of being able to hook up directly to the power grid, you know, where several large-scale nuclear reactors pump energy in. On a ship however, the level best you're going to get is a naval reactor, and while powerful, it's no technomiracle, it's power-output is strictly limited. And I guarantee you, powering a laser able to punch trough reflectively painted tungsten steel across dozens or hundreds of kilometers of atmosphere, is way beyond even the power output capabilities of a naval nuclear reactor.

Comment: Re:Patently useless (Score 0) 309

by pyalot (#35773682) Attached to: US Navy Close To On-Ship Laser Cannons
Ok, so let's speculate that they can output a continous masered high energy beam. So the unit to produce that beam will be really large, and hence, can't swivel quickly. So you need a refractor/reflector of sorts to aim it. Only issue is, at energies sufficient to burn trough basic armored steel (and no word about reflective paint), even minute devitations from 100% reflective or 100% transparent, will render any such reflector/refractor quickly useless. So after every couple of seconds of continous firing you'll have to exchange that thing, or risk it burning trough and punching random holes into your own vessel. Also, naturally you can miss, no target aquisition is 100% accurate, and then there's also refraction in air, sea movement and so on, not to say anything about multiple incoming projectiles.

Comment: Patently useless (Score -1) 309

by pyalot (#35773552) Attached to: US Navy Close To On-Ship Laser Cannons
What is the usecase of that thing?

Shooting down incoming projectiles? Good luck if the first shot misses, since you'll probably have to wait minutes for the capacitor to reload. And there's probably just one unit per ship because you'd need a nuclear reactor to power it.

Shooting at other ships? You need lasers for somali pirates, really? Oh, I see, you want to shoot at other seagoing warships with that? Good luck with that, since your run off the mill modern naval warfare is a "behind the horizon" kind of affair, I wanna see that laser shoot trough the horizon...

You want to shoot at submarines with that? (dude, I won't even go there with whats wrong trying to shoot a laser trough a randomly refracting barrier into a really light absorbing medium).

You want to shoot down satellites? Sure, you could do it with that, though, why do you need a laser on a *ship* for that? You know, satellites, they go round-n-round the earth, just wait until you have it in your sights...

Shoot at targets on land? I don't know if you've heard this, but there's a thing called "coast" and a thing called "curvature of earth", and absolutely most fat&juicy targets on land try to squat in inaccessible hilly or mountainous terrain, far, far inland. So, I want to see that thing shoot trough a horizon made of dozens of kilometers of solid rock.

Really, it's bloddy useless, unless you need to compare dick sizes with whatever other military feels compelled to do that. I hope it helps your self esteem dear US navy.

Comment: Re:But... Phong is wrong (Score 2) 169

by pyalot (#35678806) Attached to: Pioneer Anomaly Solved By 1970s Computer Graphics
So Phong is "right" for the probe, because it incidentally matches what they're seeing better? Alright, I propose a better solution, how about we invent some imaginary matter with exotic properties permeating the space, but that can't be seen, which incidentally has exactly the right properties to fit the measured data?

Saying Phong is right after fitting the calculated data to the measured data just suspect.

Comment: Re:But... Phong is wrong (Score 1) 169

by pyalot (#35678748) Attached to: Pioneer Anomaly Solved By 1970s Computer Graphics
Clearly this problem needs more effort to solve conclusively. For this purpose I'd propose constructing a probe that's as close to perfectly spherical as you can get, with a surface that's carefully adjusted to be perfectly diffuse according to the phong model, and which includes self-measuring capabilities (something like retractable cameras) to measure their own reflective properties after prolonged exposure to the solar medium.

"People should have access to the data which you have about them. There should be a process for them to challenge any inaccuracies." -- Arthur Miller

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