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Comment: Re:Tesla enables Edison to win the endgame? (Score 2) 502

by overshoot (#49793851) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

The main advantage of AC, is that it was easier to step from one voltage to another using transformers, a technology from the 1800s. With modern solid state DC to DC converters, that is no longer an issue.

Do you know what the most efficient switch is for voltages over a kilovolt? I'll give you a hint: it's not based on semiconductors. Especially for high power. There's this little matter of "breakdown voltage," for one. Also "channel resistance." When someone comes up with a transistor [1] that can do three-nines [2] voltage conversion, we can talk.

[1] And bear in mind that I spent forty years making a good living from the little darlin's. I just don't hold illusions about 'em.
[2] Check the losses that power-station transformers tolerate while doing conversions on megawatts. Those suckers get effficient.

Comment: Here we go again (Score 1) 64

by overshoot (#49489075) Attached to: KDE Plasma 5.3 Beta Brings Lot of Improvements

KDE 4 broke a lot of the functions I used on 3 (like, for instance, email. KMail was great, now I'm stuck with the inferior but functional Thunderbird). And they never did fix them. Still broken and worse with every revision.

So I'm dreading the day when the only supported KDE will be the still-not-fully-functional version 5. What have they broken now, never to fix?

Comment: This could be loads of fun (Score 3, Interesting) 113

by overshoot (#49416257) Attached to: Hyundai To Release "Semi-Autonomous" Car This Year
I have a new Subaru with their collision-avoidance system and by and large it's very nice, but its lane-boundary warning system can get ... confused by tar-patched road cracks and especially by rutted snow. Which is OK by me when it's just a warning but if the car decides to actually act on that it's going to be a wee bit exciting.

Comment: Data mining (Score 2) 179

by overshoot (#49314507) Attached to: WHO Report Links Weed Killer Ingredient To Cancer Risk

If you search all possible cancers for a connection with some chemical (e.g. sucrose) you will come up with several positives with a 95% confidence. Which is why you have to use statistical tests that account for all of the different targets.

Thus, at the very least the WHO needs to explain the stats rather than just the raw "probably causes cancer."

Comment: The fix (Score 1) 56

by overshoot (#48978649) Attached to: Lowering the Cost of Biofuel Production
I'm surprised that the blurb didn't emphasize that the microbe in question is also a nitrogen fixer. Which means that it not only produces fuels but also fertilizer without needing additional energy input (bear in mind that a large chunk of Koch Industries income is from the sale of fossil-fuel based ammonia.)

Comment: Re:Klayman (Score 1) 114

by overshoot (#48725359) Attached to: The 5 Cases That Could Pit the Supreme Court Against the NSA

It shouldn't be necessary to avail oneself of legal aid to pursue civil torts.

Klayman is a lawyer. A remarkably inept one (he gets an astonishing number of cases thrown out on grounds that most non-lawyers spot immediately.) You can look up one of his other cases recently in the news where he is representing Arizona's Sheriff Joe Arpaio in a (dismissed, standing) case against President Obama's executive orders on immigration.

Comment: Details matter (Score 5, Informative) 285

by overshoot (#48644069) Attached to: Study: Red Light Cameras Don't Improve Safety

The original red-light camera trial was in Scottsdale Arizona. The city farmed out the study to a university research group, and the cameras were installed at a random selection of the worst red-light-accident [1] intersections. The trial was publicized and ran for several years. The timing of the lights was not changed.

The conclusion of the trial was that the cameras reduced both accidents and injuries. Scottsdale then ran the cameras for years with general public approval, in part because the city has some pretty rational traffic ordinances (like raising the speed limit if most people are going faster anyway) and an open set of books on the program.

The cities that treat red-light violations as a revenue source and especially those that cut yellow times to increase red violations have only themselves to blame for poisoning public opinion. If anything, cameras should be paired with longer yellow times.

Scottsdale is strange that way. They also did studies that showed that traffic flows better and reduces accidents by having left turn after green rather than before. Those results have been mostly ignored by other cities.

PS: I've seen some of the footage from the cameras, by the way -- one truly amazing one of a guy who totally spaced and drove right through an intersection well after cross-traffic was flowing but amazingly managed to miss all of it. Hard to believe.

[1] Skip the joke. It's ancient.

Comment: Re:About fucking time (Score 1) 233

by overshoot (#48505071) Attached to: Football Concussion Lawsuits Start To Hit High Schools

The brain repairs itself by routing around damage. Although this can restore pre-injury function, it does so by using up "spare" capacity that would otherwise reduce losses due to aging or other insults.

Repeated brain injuries (like multiple subacute impacts per game) go through that reserve capacity quickly. That's what we see in middle-aged professional athletes such as boxers and more recently football players.

As for my age, yup. Retired. But I'm a volunteer emergency medic and we have to stay current, including annual refreshers that cover the state of the art. That includes the findings regarding repetitive subacute brain injuries.

Comment: Re:About fucking time (Score 1) 233

by overshoot (#48497095) Attached to: Football Concussion Lawsuits Start To Hit High Schools

Unless it's a serious concussion, I think most still go unreported.

Aside from the "all concussions are serious" aspect, in a team sport someone being disoriented should be reported by the other team members, if only in the interest of not losing the game.

However, what we're discussing here in particular is the common case where a player is clearly concussed (as in, disoriented or briefly unresponsive) and instead of being sent to hospital is kept on the bench and frequently sent back into the game after a short rest. At best, they're out for the game but back in practice the following school day and playing the following week.

Comment: Re:If I was running a school system ... (Score 1) 233

by overshoot (#48493759) Attached to: Football Concussion Lawsuits Start To Hit High Schools

Give them something better than football, and convince them that it really is better, and the world will change.

You mean like election engineering? That does seem to be right up there with football, and remarkably (given that it happens at the same time of year) the two don't seem to be exclusive.

As long as the school budget cuts don't impact the sports program, it's all good. Keeps the kids from getting funny ideas.

Comment: Re:Value your prefrontal cortex? (Score 2) 233

by overshoot (#48493725) Attached to: Football Concussion Lawsuits Start To Hit High Schools

And the schools don't dare inform parents of all the risks - parents would say "What, are you crazy? I'm going to risk my kids future so you can get a stupid trophy for your office? DIAF."

I wish you were right, but experience with the parents of brain-damaged young athletes indicates otherwise.

Logic doesn't apply to the real world. -- Marvin Minsky