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Comment: France (Score 1) 626

by photonyx (#42745171) Attached to: Will Renewable Energy Ever Meet All Our Energy Needs?
FTFY: Dawn Stover has another great piece of FUD.

and :
  1. France derives over 75% of its electricity from nuclear energy. This is due to a long-standing policy based on energy security.
  2. France is the world's largest net exporter of electricity due to its very low cost of generation, and gains over EUR 3 billion per year from this.

Now get off my lawn.

Comment: Re:Flipping the classroom..? (Score 1) 113

by photonyx (#41115401) Attached to: Why Professors Love (and Loathe) Technology

I'm not sure that you're understanding me. By professors not caring, I'm talking about the guys who don't actually teach anything and then just post the entire exam -- along with the solutions -- on their website a week before the exam, call it a "study guide" (No, it wasn't 'similar' to the exam, it WAS the exam, he just printed that out and gave it to use for the test. And it was multiple choice and fill in the blank.) The professors who don't answer questions; who take 30 minutes out of a 70 minute class just getting the computer booted up; who do nothing more than read off of slides prepared by somebody else; and who refuse to accept obviously correct answers because they're not phrased in exactly the same way it was phrased on the answer sheet.

Doesn't sound like any professor that I've encountered in my life... I guess you went to a tough college :) The worst I've seen was a professor reading from a textbook (one section == one lecture).

Comment: Math is a filter (Score 1) 1010

by photonyx (#40821385) Attached to: Political Science Prof Asks: Is Algebra Necessary?
Math and logic comprise a bullshit filter that is quite useful in everyday life, from realization that $994.99 plus tax is way over $1K, to ability to filter out general BS statements such as "spend more to save more", "15 minutes on the phone can save you 15% or more on your car insurance" etc. You need them to figure out that you'll pay double on your mortgage, and that "buy a car, get a baseball cap for free!" is not such a sweet deal. Also, you'll need it to realize that the TFA is bullshit.

Comment: Re:A boat? (Score 2) 186

by photonyx (#40403245) Attached to: The World's First Supercavitating Boat?
No it's not a submarine. From TFA:

The main compartment of the Ghost vessel, which houses the cockpit and controls, sits above the water in between two torpedo-shaped pontoons or “foils,” which are submerged and create all the buoyancy and propulsion for the craft.

Would be interesting to see it in the open ocean with the high waves. If the wave height is higher than the boat clearance it's similar to hitting the water surface at 100 mph. A nosedive at such a speed means the cockpit becomes a 12-seat grave.

Comment: Need training for recognition algorithm? (Score 1) 96

by photonyx (#39957749) Attached to: Disney Research Can Turn Nearly Any Surface Into a Touch Screen
The article says nothing about how they trained their software. Is it person-specific? I suspect that the sensor response from different people gripping the same doorknob can be quite different. Same due to sweating, dehydration, dirty hands, etc.
"Check out our new touch-recognizing doorknob! Training times may vary. We don't advise to put it on the bathroom door for at least a week after the purchase."

Comment: Re:Gasoline-like energy density (Score 1) 582

by photonyx (#39750717) Attached to: IBM Creates 'Breathing' High-Density Lithium-Air Battery
When you add up the cost of the materials for the flywheel (they need high tensile strength), the cost of maintaining near-vacuum in the flywheel enclosure (you don't want any air friction losses, do you) and the cost of service (you essentially have a bunch of rotating parts), then the flywheels lose some of their attractiveness. Low mobility and high energy loss due to friction, just to name two.

One can't proceed from the informal to the formal by formal means.