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Comment: Pointless (Score 1) 339

by lelitsch (#35156572) Attached to: Is an Internet Kill Switch Feasible In the US?

If push comes to shove, all it takes is one executive order and a few dozen US Marshalls at the overseas cable connection points and satellite uplinks and 99% of the international traffic in the US is down for at least a few days until it gets sorted out between the companies, Congress and the White House.

Comment: Re:Missiles... (Score 4, Interesting) 119

by lelitsch (#35145660) Attached to: Robot Jet Fighter Takes First Flight

Physics!

First off all, nobody is going to shoot down a UAV with an RPG, unless it is hovering at very low altitude. If you got this idea from Black Hawk down, the helicopters got shot down while they were basically hovering at roof level. A small plane going a few hundred mph is impossible to hit.

The physics part comes in, because a small missile with lower mass, much higher thrust to weight ratio and much smaller control surfaces can pull much higher g's than anything with large wings. A F-16 can pull around 9G before things start coming off, this might be able to do 15, a light AA or SA missile can pull 20-50.

So yeah, it might out-turn more than a manned plane, but not a missile.

Comment: Cheating? (Score 1) 484

by lelitsch (#35139888) Attached to: 61.9% of Undergraduates Cybercheat

I've been hearing this and similar arguments since I started college way back in 1986 and think it's just an indicator of laziness on the professors' side. Especially in engineering or sciences, it's really easy to write tests and requirements for papers that make cheating almost impossible. But recycling the same questions and the same term papers year after year and decade after decade makes it very easy for students to cheat. And this hasn't changed materially for at least 25 years. At my university, the student government had been keeping all tests and exercises since the founding in 1969 in three ring binders, so you just walked in, paid a small fee and copied the entire semester's materials. The only difference nowadays is that you can copy and paste, so students save a few hours retyping topics or copying them by hand. And one of my professor's argument that if students copy solutions, "They have to at least read it." is completely bogus in my opinion--I've taught enough labs classes to know that you can copy stuff without retaining anything.

But updating teaching materials, varying values, or just putting in actual calculations would make it easier for students to just do it themselves rather than trying to fix apply all the changes. It does require commitment by the professors and TAs, though. And obviously, copying stuff from the smart guy in class is still the preferred way of cheating.

Unfortunately, recycling tests and term papers and then trying to catch cheaters is not only pointless, but also detrimental. One of the things I had to teach newly graduated programmers for 15 years now is NOT to reinvent the wheel all the time. They are so conditioned not to copy anything that they not only search the internet for already existing code, some are even reluctant to use standard libraries. Obviously, this is not just a complete waste of company time, it also introduces hundreds or thousands of bugs, inferior implementations, and highly unmaintainable code. Libraries and other peoples' code (TM) are not perfect, but in most cases, it's good enough and better than what you hack up on your own with less than a couple of years of production coding under your belt.

So seriously academia, just stop whining, get off your butt and work on writing good tests instead of recycled assignments that facilitate copying and pasting.

Just as background, I run software planning for a $3bln+ company....

Comment: Re:Define 'observe' (Score 1) 223

by lelitsch (#34284206) Attached to: Uncertainty Sets Limits On Quantum Nonlocality

Actually, if you would have read past that point, you'd have seen that the process is actually very rigorously defined. It's when whatever particle you use to observe the system interacts with the system. So if you bounce a photon of an electron, that's the observation, not when the photon comes back to hit the photo receptor.
The problem is that this rigorous definition is way past what you want to go into in a beginners guide. A good place to start is looking up quantum decoherence. But the short version is that without an observation, all quantum states are superimposed and we don't know which one the particle or system is in. To get this information, we need to probe it, and since all the possible probes we have are other elementary particles, there is going to be some interaction and the system drops into an Eigenstate with the energy or momentum you wanted to observe (obviously not at the same time, see the uncertainty principle.

In your example, the bat doesn't observe the system directly, the "observation" happens when the photon that hit the bat's eye bounced off whatever it bounced off to get there. Or when the sonar pulse sent by the bat hit whatever it bounced off off.

(and yeah, I know this is so not mathematically rigorous, or correct to the 10th order)

Comment: Nice article, not mirrored in reality (Score 4, Interesting) 329

by lelitsch (#33980712) Attached to: Why Silicon Valley Won't Be the Green Car Detroit

Nice polemic, and echoed widely. On the other hand, California leads the entire US by "value added by manufacturing" and on its own dwarfs the entirety of the Southern states the authors hold up as an example. For example, according to the US Census Bureau, California created $254bln in added manufacturing value with 1.3 million workers in 2008, South Carolina: $37bln with 230000 workers. If you crunch the numbers, you'll also see that California produces more value per worker than most other states. And until the meltdown last year, one of the primary car factories in the US was Nuumi in Fremont, CA, actually the Toyota plant Tesla bought.

Yes, once prices come down and everyone can do it, it'll probably electric car manufacturing will probably move to other states and California will get started on the next thing. But to get this off the ground initially, Silicon Valley is a great spot, because all the expertise you need to debug the process is within a two hour drive.

And by the way, Porsche, Mercedes, Audi, and BMW main factories are in Germany's most expensive areas, very few are in the more depressed parts (although Wolfsburg is really depressing).

Apple

+ - Apple now makes more money from phones than Nokia

Submitted by lelitsch
lelitsch (31136) writes "According to a market research company, Apple operating profit from the iPhone was $1.6 billion last quarter while Nokia recorded $1.1 billion.
Obviously, Nokia still sells vastly more phones than Apple, but with these profits, Apple can spend vastly more money on improving the iPhone than even Nokia can on their flagship model and completly bury Palm's R&D spending."

Comment: Re:Won't Win Wars (Score 1) 252

by lelitsch (#28287787) Attached to: Wired for War

Germany: won. We destroyed the army, roughed up the citizens for being a bunch of nasty losers, and then set about making them BFFs.

I don't remember that the US carpet bombed every large North Vietnamese city. Even Rolling Thunder had lots of restrictions what the USAF, Navy and Marines could hit.

Comment: Re:Probably a lot less likely. (Score 1) 884

by lelitsch (#28224657) Attached to: Could a Meteor Have Brought Down Air France 447?

Wow, bad astronomy indeed. For the odds of a meteorite striking one of many airplanes, the speed of the airplane is pretty much irrelevant. His calculation is sort-of correct(ish) for a single airplane and a single meteorite. But since we have thousands of airplanes and hundreds (or thousands)of meteorites in the atmosphere at any point in time, it evens out to the relative surface area of all planes.

A simple picture of it: all planes fly in a shell around the earth between 10000 and 13000 meters, all meteorites that don't break up in the upper atmosphere go through that shell. So the ones in the fraction covered by the combined surface area of planes hit planes. Strictly speaking, it would be the fraction of volumes in a shell that's as thick as the average plane is high, but would actually increase with slower meteorites, not decrease.

   

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