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Comment: Re:A Bit Fishy (Score 4, Informative) 365

by gman003 (#49355867) Attached to: Modern Cockpits: Harder To Invade But Easier To Lock Up

Your TFH is on a bit tight, but your real problem is lack of knowledge.

Computers are not "in control" of Airbus aircraft, any more than computers are in control of Ford cars. There is absolutely a manual - it just isn't a physical link, because we've moved beyond wires and pulleys, or even hydraulics.

Large aircraft are designed for skilled pilots - ones who can respond to the often unusual disasters that strike when in the air. There's an override for everything, because you never know when you might need to do something unusual in response to some other failure. Want to engage the thrust reversers while in-flight? Sure - normally that would be catastrophic, but that might be the only way to prevent an overspeed in a steep dive. Want to land without lowering the gear? It'll yell at you but it won't stop you.

In fact, very few things even require an override. The normal thing for an aircraft to do when it thinks the pilot is making a mistake is to yell at them, not stop them. And in this case, we have on the cockpit voice recording the sounds of the alarm saying "PULL UP. PULL UP. PULL UP."

But the aircraft didn't stop him, because there are easily dozens of situations where stopping him would have been even worse. For example, an all-engines out emergency landing. Or a GPS malfunction, and there's no mountain there. Or... you get the picture.

There are no aircraft that don't have a mode that acts like manual. There are a few military aircraft where, even in manual, the flight computers will make constant control movements to keep it stable, but even in a B-2, if you slam the stick forward, it'll dive right into the ground.

Comment: Knowing how it works != knowing how to build it (Score 4, Informative) 339

by gman003 (#49332203) Attached to: Feds Attempt To Censor Parts of a New Book About the Hydrogen Bomb

I know how suspension bridges work. I probably could build a small one, but any lengthy span would be well beyond me.

I know how internal combustion engines work. It would take a year of training on the tools before I'd be able to make one that even sorta worked, and then it would be at 1900s-level functionality.

I know how nuclear weapons work. Several types, in fact. But I cannot make them.
1) I could build a gun-type weapon, given the material (200lbs of 90% pure U-235, a 76mm artillery barrel, and some regular explosives), but I could not create the equipment to refine uranium.
2) I could probably build a reactor to generate plutonium, with massive effort and a significant risk of poisoning myself, but I could not build a working implosion bomb with it. It would take a year's training in explosives just to be able to build an existing design, and those designs are tightly secured.
3) With the materials, I might be able to upgrade an unboosted fission weapon into a boosted one. Maybe.
4) A fusion weapon is completely beyond me. You could stick me in Lawrence Livermore with all the parts in front of me, and without some Ikea-like instructions you aren't going to get anything.

We are protected from homemade gun-type weapons by the scarcity of uranium and the immense difficulty in refining it. Remember, this is something that was beyond the capabilities of most nations a scant 70 years ago. A dedicated nation-state or perhaps certain multinational corporations could pull it off, but not without detection.

We are protected against homemade implosion-type weapons by the complex engineering necessary, the esoteric nature of the specific engineering knowledge needed (nuclear physics and shaped explosives are not a common dual-major), and by the absolute need for testing before use. The former prevents fringe groups from succeeding; the latter prevents the non-suicidal from trying.

We are not protected by lack of general knowledge on nukes, because no such lack of knowledge exists. I learned half of this stuff from school textbooks, and the other half from Wikipedia. Anyone driven to find more can easily do so.

Comment: Unfairly biased against small projects (Score 1) 515

by gman003 (#49329899) Attached to: A Bechdel Test For Programmers?

The key point this misses is that the Bechdel test is about the work itself, not who wrote it. This test is thus susceptible to certain flaws. In particular, it will flag numerous single-developer projects as "sexist" due to simple chance.

This would fail at least 50% of all single-developer projects, even if there were no sexism anywhere. Other small projects would be unfairly penalized, and projects with tiered architectures and tiered development would be especially susceptible.

This is obviously contrary to the goal of the "test", and in fact bears only superficial similarity to the Bechdel test (the point of which, by the way, is not to determine which works are sexist or not (after all, Debbie Does Dallas passes), but to show how endemic weak female characters are by the sheer number that fail).

Comment: Who controls movie ratings? (Score 2) 128

by aitikin (#49296941) Attached to: Why Is the Grand Theft Auto CEO Also Chairman of the ESRB?
As I recall, the MPAA rates movies in America...why should the video game industry be considered at fault for having someone who is at the head of their industry be faulted when the movie industry isn't? Aren't people supposed to be encouraging the "self-regulation of the free market" or something like that?

Comment: Re:Or maybe it's because (Score 1) 114

by aitikin (#49286991) Attached to: Stanford Study Credits Lack of Non-Competes For Silicon Valley's Success
The implication (at least that I get) is that people who are creative and inventive thinkers will immigrate to California because (at least in their eyes) if it doesn't work out, they can just quit and find another job because there's no non-compete clause. I know when I signed my contract for my current position, I was very wary of the fact that there was a non-compete clause, but then I realized what any first year law student would in looking at my job and the non-compete, it's completely unenforceable.

Comment: Re:Sigh (Score 1) 110

Compute might use it. The Titan was traditionally both the top-tier graphics card, as well as the entry-level compute card. They've slashed FP64 performance with this iteration, but FP32 performance is still sky-high, and they're pushing situations like that for using this as a compute card.

Comment: Re:Something completely different... (Score 2) 667

by gman003 (#49264645) Attached to: Why There Is No Such Thing as 'Proper English'

The lack of a prescriptive body for English is a historical accident, the same way the United Kingdom doesn't have a constitution, just a shitload of case law, treaties and statutes. For quite some time, Norman French was the language of government - naturally, the government did not try to regulate the grammar of a language they never spoke. After that, it was a populist thing - trying to formalize English would cause backlash at your supposed elitism. There was a brief window where a prescriptive body could have been formed, but soon enough there were too many far-flung colonies (and then former colonies) to do so effectively. Now you can't get a single prescriptive body at all, because the British will never bow to an American body, the Americans will never bow to a British body, and there's enough foreign speakers that they could arguably form their own prescriptive body and make it stick to everyone but the biggest two.

It also fails to note how prescriptive bodies often fail when they try to dictate usage, instead of formalizing actual usage. The French Academy, for instance, insists that the proper word for email is "courrier electronique". Informally, most French just use "email" or "mel", and the Quebecois managed to standardize "courriel". It's a bit of a joke, really, how little authority the French Academy actually has to dictate French.

Prescriptivism is fundamentally unworkable for languages in general use. The best prescriptive bodies do not dictate language, but formalize existing practices, and standardize where inconsistent. They may title themselves prescriptive bodies, and may sometimes try to dictate usage themselves (and usually fail), but at heart they are not prescriptivist.

Comment: Re:Are Brown Dwarfs Stars? (Score 5, Informative) 98

by gman003 (#49247091) Attached to: Proxima Centauri Might Not Be the Closest Star To Earth

There's a continuum of sorts between gas giant planets and dwarf stars, with a few notable points where you could draw the distinction. They all come from the same general start - a cloud of interstellar gas collapses into a spherical object. Depending on how big it is, you can get different objects.

First you have gas giants, no fusion at all. This would be your Jupiter and Saturn type planets. Jupiter is actually about as big, volume-wise, as a gas giant can get. Add more mass, and it starts getting denser rather than bigger.
At 13 Jupiter masses, you have enough gravitational pressure to fuse deuterium. This is what most astronomers define as a brown dwarf star, but others, and apparently you, consider it to still be a planet. Previous terminology included "substar", which I would not be opposed to. Deuterium isn't particularly common, so these objects glow very dimly, as far as stars go.
At 65 Jupiter masses, you can start fusing lithium as well. This is one way to distinguish brown dwarfs from other stars - red dwarfs and yellow dwarfs, like our sun, consume their starting lithium very quickly, and so the presence of lithium spectra indicates a brown dwarf.
At around 80 Jupiter masses, it starts fusing hydrogen, becoming a red dwarf, like Proxima Centauri. Still very dim, but at this point it's undeniably a star.
At around 750 Jupiter masses, the star develops a more complex internal structure, and becomes a yellow dwarf, such as Sol.

So where do you draw the line? Anywhere you want, but most astronomers settled on the simplest one: if it's undergoing fusion, it's a star, if it isn't, it's a planet.

Comment: Re: Following instructions? (Score 4, Insightful) 190

by gman003 (#49246337) Attached to: Powdered Alcohol Approved By Feds, Banned By States

Ever since I heard the "dehydrated water" joke, I thought it would be a brilliant name for a water-purification powder, like the stuff you use while camping.

Instant water, just add water - but the water you add doesn't have to be clean, and the water you get is drinkable. Memorable brand if nothing else.

Comment: Re:Is it unconstitutional? (Score 3, Informative) 82

by gman003 (#49231265) Attached to: South African Government Issues Plans To Censor Internet

Their Bill of Rights is very broad, covered in Chapter 2 of their constitution. Disclaimer: I am not a lawyer in any country, and this was my first time even reading their constitution, but it seems pretty obvious that it won't allow censorship of the internet.

Section 16: "Everyone has the right to freedom of expression, which includes [...] freedom to receive or impart information or ideas"

Section 32: "Everyone has the right of access to any information held by the state; and any information that is held by another person and that is required for the exercise or protection of any rights"

Depending on implementation, if might also breach Section 14: "Everyone has the right to privacy, which includes the right not to have [...] the privacy of their communications infringed" ... I kinda want this bill of rights in my own country. Gotta say, it looks pretty nice.

Yes, we will be going to OSI, Mars, and Pluto, but not necessarily in that order. -- Jeffrey Honig