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Comment Re:Fuel Tax Works Fine (Score 1) 932

What is the difference between this and the already-in-place fuel tax? The fuel tax is even better at metering costs to those that chew up roads (heavy vehicles). This sounds like a solution looking for a cause to me.

while the already in place fuel tax is a fair way to tax vehicles, its possible that a per-mile tax could lead to a more progressive tax structure, where heavy users are disproportionately taxed... similar to the federal income tax structure. Not that I'm a big fan of that...

Submission + - Hydrogen fuel cells with non-platinum catalysts (sciencedaily.com)

tbischel writes: Los Alamos National Laboratory scientists have developed a way to avoid the use of expensive platinum in hydrogen fuel cells, the environmentally friendly devices that might replace current power sources in everything from personal data devices to automobiles.

Comment Re:plagiarism differs in science vs. English Lit. (Score 1) 111

"Pick up any math paper on number theory, and you're bound to find the sentence 'Let p be an odd prime number.' without citation, but that would hardly qualify as plagiarism."

I wonder how often you see specifically an odd prime number... since two is the only even prime, its really the oddest of the bunch.

Comment Re:Still skeptical about all-electric cars (Score 1) 359

Here is an interesting study on electric powertrains... it comes to some remarkable conclusions about the wheel to well efficiencies of different technologies, and the long term cost projections... Their analysis seems to point to Battery Electric Vehicles as the least likely long term solution to the transportation section, instead favoring HEVs, PHEVs, and FCVs. Very interesting read!

Comment Re:I'll wave when I drive past you ... (Score 1) 359

Hydrogen will always lose out, because it's simply an energy store and not an energy source. Anyplace we can get hydrogen from? No. We have to convert natural gas to hydrogen (might as well run vehicles on natural gas) or crack H20 into hydrogen with electricity (which is horribly inefficient). Electricity is the end game.

If electric cars were the best solution (or energy efficiency was the only concern), we would be exclusively burn oil in more efficient power plants, and using that to charge batteries in cars... rather than converting crude to gasoline to fill up.

Comment Re:Algorithms? (Score 1) 116

well I certainly am not a trajectory analyst or anything, but the guy next to me uses STK to do his analysis (the astrogator plugin). You could be right that they are using Titan to do a swingby, but I've seen some pretty crazy trajectories as a result of unstable orbits around Lagrange points. That is the basis of the space highway.

Comment Re:Algorithms? (Score 1) 116

They probably are using a tool like this to analyze possible trajectories... these tools do use numerical optimization libraries to pick paths between targets and destinations. Just guessing based on what was said in the summary, they are using the Saturn-Titan Lagrange points to alter their trajectories without using much fuel. You can do some pretty crazy maneuvers around these points.

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