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Comment Re:You're both right, and both wrong. (Score 1) 311

What makes you both partially correct is that there isn't a delay in fission, but a delay in neutron release.

From reading the linked Wikipedia page, I get that the delayed neutrons are responsible for 0.6% of all neutrons emitted from fission, and most of them with half-life times between 2 and 20 seconds. While this makes for some nice control bandwidth (you can afford to be 0.6% off with the control rods without getting an instantaneous nuclear explosion), I don't see how these delayed neutrons can be responsible for the majority of the 7% decay heat.

Comment Re:Nuclear plants don't like sudden shutdowns (Score 2) 311

"Normally there is some time between neutron capture and actual nuclear fission (I have heard a figure of 15 minutes)."

The fact that you can detonate a nuclear bomb by bringing together two subcritical pieces of U-235 shows that this can't be true.

In a nuclear reactor, 7% of the heat output is from the decay of the fission products (alpha and beta decay). This 7% will continue to be generated regardless of control rods or neutron absorbers. It will last hours to weeks, depending on where you put the threshold for "finished". Remember Fukushima: it became a disaster when the water circulation backup pumps failed 12 hours after the reactor shutdown.

Comment Re:Nope, still a story. :) (Score 1) 215

A charge station at home is just a wall socket- you can literally just plug your car into the wall and charge it already.

So EVERY house that is on the grid is already EV infrastructure.

The numbers show that the existing grid can (with some exceptions) handle EV charging (which would and should be mostly at night where the grid is underutilised anyway.)

Comment Re:This is great! (Score 1) 215

Actually, the electricity can come from renewables.

Some places have hydroelectricity, nuff said.

Also, wind power and solar is available nearly everywhere, and electric cars do great on that; they don't normally need to charge up everyday, and when there's a glut of wind or solar they can suck it down; and (if you have the right equipment) even sell it back again.

Comment Re:The Greater Danger (Score 1) 180

"until the discovery of the chirality (and chirality affects a lot of things) of saturated fats, they probably got mixed together (they're still saturated fats, after all) and the original problem was because of the hidden trans- version."

I think you are mixing up things. Trans and cis fats are both unsaturated fats, with double bonds. Saturated fatty acids have no chirality. (Well... Triglycerides are technically often chiral (the middle carbon atom of the glycerol backbone), but that's not relevant for the cis/trans/saturated discussion.)

Comment Re: Be careful not to justify government corruptio (Score 1) 215

"I recently heard about a case called "Kids For Cash", where a judge was sending lots of juveniles to a privatized detention center and getting paid for each."

Actually, two judges: https://en.wikipedia.org/wiki/...

Quote: For example, Ciavarella adjudicated children to extended stays in youth centers for offenses as minimal as mocking a principal on Myspace, trespassing in a vacant building, or shoplifting DVDs from Wal-mart.

Comment Re:I don't think this [release] matters at all... (Score 1) 193

"I use lightweight WMs such as XFCE or Openbox. Not a fan of the bloat..."

XFCE isn't that much lightweight compared to MATE (i.e., Gnome 2), only compared to Gnome3/Unity/KDE.
https://flexion.org/posts/2014...

Where did XFCE get this lightweight reputation? It surely doesn't look very polished (based on looking over other people's shoulders only).

Comment Re:Not Photosensitive (Score 1) 192

"A 100mW red laser pointer aimed"

You play around with a HAND-HELD class 3b laser? Still have eyesight in both your eyes? (And your pets/household members)

Legally, those should be operated only by trained staff and I believe they must be equipped with a key lock and interlock connection. That stuff from WickedLasers should really be banned. The laser inside a dvd writer is of similar power, but interlocked and much less dangerous due to the focusing lens.

Comment Re:Kind of.. (Score 1) 481

"Except you forgot to pay gas, maintenance and insurance on those 40 miles."

And depreciation, say $15k over 150k miles is another $0.10 per mile (I'm not from the US, not sure of typical car prices and lifetime mileages. YMMV)

Car owners typically don't count depreciation "because they have the car anyway". However, once infrastructure (or choice to live and work close to mass transit) is available, you can choose not to own a car and rent one for the few occasions you need one.

Apart from those costs, your own time may also have value. IMO, time spent driving is a waste and costs me EUR 20/h in loss of life quality. Time in the train I use to read the newspaper or slashdot (or post comments, like now). The bike ride to the station is my primary form of exercise (no gym subscription).

Comment Re:Here's a great idea... (Score 1) 481

"GPS receivers have been in cell phones for years. The cost of the receiver doesn't add $1,000 to the phone."

The ones on phones don't need to be certified, tamper-proof, and linked to a database with financial consequences. Because of privacy issues, you'd probably want the unit to only log distance per day, not full location information. So,.reliability is extremely critical.

See alcohol locks (whatever they're called) for people with a multiple DUI conviction. You can get an uncertified breath analyzer gadget for a few dollars/euros, but the ones that are actually attached to a car are hundrds of dollars.

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