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Comment: Re:Density matches theory (Score 3, Interesting) 50

by ceoyoyo (#49738015) Attached to: Martian Moons May Have Formed Like Earth's

The impact hypothesis nicely explains why the moon is less dense than Earth: the impact preferentially threw up light elements from the crust and upper mantle, not heavy elements that would have sunk to the core. The densities of Phobos and Deimos are also less than that of Mars, but because they're so small, and are probably more like orbiting gravel piles, their densities are also consistent with small asteroids.

Comment: Re:Aphelion vs Parhelion (Score 2) 50

by ceoyoyo (#49737959) Attached to: Martian Moons May Have Formed Like Earth's

"many of the planets have orbits that are very near circular, but we do not interpret their existence in a similar fashion."

We do actually. It's pretty well accepted that the planets around the sun coalesced from a protoplanetary disc surrounding the young sun. The impact hypothesis for moon formation is similar: a big impact causes debris to be thrown into an orbiting disc around the planet and one or more moons then coalesce out of it. The alternative, capture of a separately orbiting body, isn't seriously considered for the origin of the planets.

Comment: Re:It's My rant (Score 1) 612

by ceoyoyo (#49709413) Attached to: The Economic Consequences of Self-Driving Trucks

See my third paragraph. You're implicitly buying into the myth that people losing their jobs to automation makes the economy poorer. The opposite happens: there's more wealth. Even if a significant number of people lose their jobs and don't get new jobs (or get crappy ones), that loss is more than made up by someone (or everyone) else having more money. There are always customers. The decision whether it's a few super rich people being waited on hand and foot and some people working as gladiators in the entertainment arenas (reality television) or a more equitable distribution, such as in Switzerland where everyone is guaranteed a minimum income, is a political problem that will be solved one way or another. The free market is quite capable of sorting it out by itself, but that way is almost sure to be a lot nastier, probably involving food riots and rich people lined up against walls.

Comment: Re:Won't save most of the 4000 lives (Score 1) 612

by ceoyoyo (#49709385) Attached to: The Economic Consequences of Self-Driving Trucks

Sure, a truck going the same speed as a car can have the brakes fail completely, or the driver have a heart attack too, then it can take twice, three times, or arbitrarily longer to stop than a car. Or vice versa. Sorry, I assumed you were trying to say something relevant.

I quite pointedly said that things are somewhat more complicated with real vehicles than the simple physics analysis of locked wheels. It's not my theory, it's basic physics (which you claimed did not support my original post), and also the formula that most police forces use to estimate (note, estimate) the speed of vehicles involved in collisions.

You are completely ignoring the fact that, as I posted, US regulations require trucks be able to stop in much less than twice the distance cars can, and test results that indicate most (well maintained) trucks can stop quite a bit better than required. In real life, as is demonstrated in transport safety statistics, large trucks are quite frequently poorly maintained and so their stopping distances may well be longer.

Comment: Re:It's My rant (Score 1) 612

by ceoyoyo (#49707549) Attached to: The Economic Consequences of Self-Driving Trucks

Sure you can. Right up until 100% of us work in service. The majority of us already do, mostly selling each other stuff.

Personally I hope it really does get to the point where people realize how ridiculous it is and we all cut back on how much we work.

The issue of wealth distribution is an entirely different matter, and it's much more of a problem in the US than in any other modern economy. It's not a hard problem to solve technically, although prevailing attitudes in the US seem to make it quite difficult. Technology and automation make economies more efficient and the countries who own them richer. Replacing truck drivers will reduce the price of virtually everything, for everybody. It's a political decision whether you want that increased wealth to go to a few people who don't need it, leaving everyone else poor, or to be spread more equitably.

Comment: Re:Won't save most of the 4000 lives (Score 1) 612

by ceoyoyo (#49707309) Attached to: The Economic Consequences of Self-Driving Trucks

Friction force is a function of the coefficient of friction times the downward force. The simple physics interpretation says that the stopping distance is independent of the "amount of rubber per pound":

http://en.wikipedia.org/wiki/B...

In practice, particularly with anti-lock brakes, the situation is a bit more complicated, but it shouldn't be as bad as double. I notice that you've chosen the "truck with hot brakes" versus the car, presumably with cool brakes, for your comparison. That's not only not a fair comparison, riding around in emergency braking situations with hot brakes all the time is the result of either poor maintenance or poor driving.

Note that US federal regulations require large trucks to stop in considerably less than twice the distance of passenger cars (or even motor bikes), and that tested trucks average quite a bit better than that maximum: http://www.nhtsa.gov/DOT/NHTSA....

So if a truck does take twice the distance of a car, it may literally be criminally poorly maintained.

Comment: Re:It's My rant (Score 1) 612

by ceoyoyo (#49706581) Attached to: The Economic Consequences of Self-Driving Trucks

History disagrees with most of the things you said. As menial, unskilled and repetitive jobs get eliminated, the service industry grows. Fast food servers have been useless for a long time, but they're very rarely replaced by automation. The enormous service industries that are hallmarks of successful western economies are make work programs because we have this antiquated idea that everyone needs a 40+ hour a week job. Plus, most people like having others serve them.

Comment: Re:Won't save most of the 4000 lives (Score 0) 612

by ceoyoyo (#49706527) Attached to: The Economic Consequences of Self-Driving Trucks

If there's that much difference in stopping distance then the truck is criminally poorly maintained. If you get rid of the reaction time and finally fix brake lag, then the truck may well have an advantage in stopping, especially at lower speeds. In a realistic braking situation, where the driver in front doesn't just slam on the brakes full as soon as he pulls in front, the automated trucks will probably have a huge advantage. Plus they don't get tired and inattentive.

Disclaimer: "These opinions are my own, though for a small fee they be yours too." -- Dave Haynie

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