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Comment: The failure mode is transformer core saturation. (Score 1) 30

by Ungrounded Lightning (#47536253) Attached to: The Truth About Solar Storms

High induced votlages in open wires are a problem, but they're not the big one.

The biggie is common-mode currents in long high-voltage transmission lines adding a strong DC component to the current in the substation transformer windings - high enough that when the same-direction peak of the AC's cycle adds to it, the core saturates. Then the inductance of the transformer drops to the air-core value and no longer substantially impeeds the current.

The current skyrockets. The resistive heating of the windings (and the force on the wires from the magnetic fields) goes up with the SQUARE of the current. The windings quickly soften, distort, form shorted turns, melt, open, short out to the frame, etc. The transformer is destroyed, or committed to a self-destructive progressive failure, in just a handful of such cycles - too fast for the circuit breakers to save them (even if they DO manage to extinguish the arcs with the substantial DC component to the current.) Even if the transformer doesn't explode and throw molten metal, gigawatt sustained arcs, and burning oil (or burning-hot oil replacement) all over the substation area, it's still dead.

This happens to MANY of the giant transformers in the power grid. Each set of three transformers that has one or more failed members means a high-voltage transmission line that is shut down until the transformer is replaced.

There are essentially no spares - these are built to order. Building one takes weeks, and there are few "production lines" so little parallelism is available. What is destroyed overnight will take years to replace, while each intercity power transmission line is not functioning until the transformers at its end ARE replaced.

The current occurs because the transformers are organized in a "Y" arrangement, and the center of the Y is grounded at each end (to prevent OTHER problems). The transformers have enough extra current handling capacity to avoid saturation from the DC through that center connection to/from ground from ordinary electrical and solar storms - just not a giant one like we get every couple centuries.

The solution is to put a resistor in that ground connection, to limit the DC in the lines (and dissipate the energy it represents). Indeed, a few lines have such resistors already.

But a suitable resistor is a box about the size of one of the transformers. It's very expensive. And it only makes a substantial difference to the operation of the lines in such a once-in-centuries event. So most executives don't spend the money (and get dinged for costing the company millions) to put them in, to prevent a failure mode that hasn't happened in the generations since Tesla and Westinghouse invented the three-phase long-line power grid.

Or at least they don't until the regulators or their stockholders require it. Which means said decision-makers need a little educational push to decide it's worth the cost and get it done.

Thus articles like this. B-)

Comment: Presbyopia (Score 1) 519

by Ungrounded Lightning (#47525653) Attached to: Laser Eye Surgery, Revisited 10 Years Later

I'm up around retirement age. My eyes don't chage focus much at all. So I have to swap lenses to go from distance to close-up vision. (Yes I could use some kind of bi/tri/progressive-focal lenses. But at the moment swapping is adequate for me.)

Until they find a way to correct presbyopia (and they don't see to be even researching it), I'd still have to don/remove glasses anyhow. With my extreme astigmatism, extreme nearsightedness, and substantial age, I'm not a good candidate for lasic and stand a substantial chance of visual artifacts from it. I'm also a target shooter, so my glasses double as eye protection.

Given all this, the potential benefits for me would be small and the risks and cost oughtweigh them.

But if they ever find a way to fix presbyopia the equation could change substantially.

Comment: Re: Just let me do brain surgery! (Score 4, Insightful) 367

by krlynch (#47518593) Attached to: 'Just Let Me Code!'

Of course brain surgeons don't "just do" brain surgery .... in any surgery, there's a ton of pre-operative work, investigation, preparation, paperwork, practice, etc. No one just dives in and cuts open your head.... and just as no one administrator hovers over the scalpel's every move, no manager hovers over every keystroke, either.

Comment: Re:a question.... (Score 1) 63

by Rei (#47516505) Attached to: Oso Disaster Had Its Roots In Earlier Landslides

That's not what everything I've read about the disaster has said. The mountain has gone through cycles - whenever it collapses, the river gets moved away, and the slides stop for a time, but eventually it wears away the footings enough that it falls again. They'd even tried to prevent landslides there by manually shoring up the base back in the 1960s, but it just flowed over their reinforcements.

The waterlogging of the soil is also a necessary factor too, mind you - not saying otherwise. :)

Comment: Re:a question.... (Score 1) 63

by Rei (#47516433) Attached to: Oso Disaster Had Its Roots In Earlier Landslides

I had paperbark birch seeds, which are also pretty water tolerant (though not as much as river birch), but none sprouted - ironically I think the seeds were too wet when I stratified them (same with my maples). Isn't river birch (B. nigra) a warm-weather birch species? I've got some cuttings of random local birches from a neighbor but I have no clue whether any of them are water tolerant enough to take swampy ground. Also birches don't usually get that tall so I don't know how expansive of a root system they'll put down. The abundant local species B. nana (dwarf birch) grows (nay, volunteers) readily here almost anywhere that sheep don't graze, but it's just a shrub, I doubt it'd do the trick (though it's probably better than just grass). It can take wet soil, although not totally swampy conditions.

For the wetter areas I also have about a dozen or so western redcedar seedlings - they're not as swamp-tolerant as dawn redwood and western recedar, but they're still reportedly quite tolerant of wet or even waterlogged soils, and they should be more cold/wind hardy than those two (wind is actually the big issue, it doesn't really get that cold here). I've also got a number of other pacific northwest trees with varying degrees of standing water tolerance. Oh, and a species or two of tasmanian mountain eucalyptus (don't remember which ones) that tolerate fairly swampy ground and should at least stand a fighting chance against our winds.

Basically, I'm just going to plant a ton of stuff and see what survives. ;)

One plus is that where the ground is persistently wet and at landslide risk, it is slowly flowing water, it's not standing. It's constantly replaced by fresh, cold ground-filtered water, so there's probably not as much risk of root rot as might be common otherwise. But there's still the oxygen issue. That and the damned sheep, but I'm working to fix that issue once and for all...

Comment: Re:a question.... (Score 1) 63

by Rei (#47514829) Attached to: Oso Disaster Had Its Roots In Earlier Landslides

To be fair, if you look at the scale of that thing, what fell is far deeper than tree roots are going to go.

There was a landslide on my land a few years ago... actually just 50-100 meters from where I'm getting ready to build my house (but the terrain is different, that's a groundwater-infiltrated glacial till-underlain marsh while my house site is basalt bedrock). It's weird looking at pictures of this giant slide, how much it looks like a 20x bigger version of my little one, from the smooth, rimmed conchoidal scarp to the river-damming piles of debris at the bottom. In my case, there were no trees, but there was grass. The grass managed to hold it for a while... but not forever. The roots just don't run deep enough. In my case, the solution (in progress) is surely just to plant water-tolerant trees (here's to hoping that dawn redwood and swamp cypress can survive in Iceland...). But what sort of trees could anchor such a massive slope as the Oso one? I know a lot of desert trees like mesquite can have super-deep root systems, but they wouldn't grow in Washington.

Comment: Re:Pft (Score 0) 918

by Rei (#47513945) Attached to: The Daily Harassment of Women In the Game Industry

You do realize how commonly men are beaten and murdered, don't you?

Eat your red herrings on your own time. And the next time you pick a red herring in a discussion about rape, you might want to pick one that doesn't also apply virtually equally to women.

Carrying a knife will even things out quite nicely, though. Clawing out eyes works pretty good, too.

Great, so let me see if I've got you right. I'm supposed to walk around armed at all times (illegal here), and try to claw out the eyes of someone who's strong enough to pick me up and carry me up a hill as if it's nothing and could almost certainly easily beat me to a pulp, and if I don't, then it's my fault and its not really rape? Is this what you'd consider a just society, just laws and just standards? Where through no fault of her own a woman can be given the choice between "be f***ed by some guy you don't want to" or "get most likely beaten to a pulp and then f***ed by him", and if she chooses the former, even if she says no over a hundred times and tries repeatedly to walk away, then there's no crime?

Comment: Re:Pft (Score 1) 918

by Rei (#47513921) Attached to: The Daily Harassment of Women In the Game Industry

I found the cited article (always with the indirect sources...) ("No Penis, No Problem"), but I'm having trouble tracking down some of their data for further analysis.

For example, I found the CIUS data on rates of arrest for various sex crimes, and the numbers match, but they don't define non-rape "sex offenses except forceable rape and prostitution" anywhere that I can locate. Given that indecent exposure, for example, is usually classified as a sex offense excluding forcible rape and prostitution, that kind of matters.

I tried to track down that "large survey of college-age women" (cite 111), but the citation is just to a book which isn't available online (at least not the relevant part). I cross-checked the author's name and the claimed data and found no peer-reviewed publications about it.

The cite for 112 is the same as for 111.

The cite for 116 is interesting because most of the results I find when I search for it are criticizing the authors for using bad methodology to support a "satanism scare", that nursery school teachers are ritually sexually molesting children for satanic purposes. It was only focusing on cases supposedly connected to satanism, and was alleging that there's a widespread problem with women running day care centers hold satanic parties with the whole staff taking part in mass sex abuse. Needless to say, this was another book, not a peer-reviewed paper.

The cite for 117 is the same as for 111.

Comment: Re:Pft (Score 2) 918

by Rei (#47513831) Attached to: The Daily Harassment of Women In the Game Industry

Oh, and for this?

Females using implements still didn't count as attackers of males under that one either, natch

May I direct you to:

14-27.5. Second-degree sexual offense.
(a) A person is guilty of a sexual offense in the second degree if the person engages in a sexual act with another person:
(1) By force and against the will of the other person; or
(2) Who is mentally disabled, mentally incapacitated, or physically helpless, and the person performing the act knows or should reasonably know that the other person is mentally disabled, mentally incapacitated, or physically helpless.

and

Sexual act also means the penetration, however slight, by any object into the genital or anal opening of another person's body: provided, that it shall be an affirmative defense that the penetration was for accepted medical purposes.

Oh, gee, but some guy gave some "bitches, they got it easy about rape" rant and you believed him.

Comment: Re:Pft (Score 2) 918

by Rei (#47513821) Attached to: The Daily Harassment of Women In the Game Industry

Again, another case of "info I heard from some guy that made me mad so I'm repeating it here".

North Carolina's rape law The basics? North Carolina does indeed consider only vaginal sexual assault "rape" (first degree or second degree), but immediately below that they list the crime of "sexual assault" (again, first degree or second degree), which covers everything else and has the exact same penalties. So it's just a state legal terminology issue and has no practical consequences.

These things take 10 seconds to look up, is that really that onerous to do before pushing a "women are a bunch of coddled whiners when it comes to rape and men are the real victims" attitude on public forums?

Comment: Re:Pft (Score 1) 918

by Rei (#47513795) Attached to: The Daily Harassment of Women In the Game Industry

Do you people get your information from a game of telephone or something? Seriously, double check things before you post.

Texas's rape law The basics?

22.011. SEXUAL ASSAULT. (a) A person commits an offense if the person:
(1) intentionally or knowingly:
(A) causes the penetration of the anus or sexual organ of another person by any means, without that person's consent;
(B) causes the penetration of the mouth of another person by the sexual organ of the actor, without that person's consent; or
(C) causes the sexual organ of another person, without that person's consent, to contact or penetrate the mouth, anus, or sexual organ of another person, including the actor;

No exceptions for gender.

Comment: Re:Pft (Score 1, Informative) 918

by Rei (#47513779) Attached to: The Daily Harassment of Women In the Game Industry

1, to the GP: RAINN says that 1 in 6 women has been the victim of rape. That's different from "will be over the course of their life". That rate is guaranteed to be higher. 1 in 6 in the "have been" category would imply that 2/3rds of the average surveyed woman's rape risk is behind them to reach the 1 in 4 figure, which is not at all an unreasonable assumption.

2. When you want to cite data, don't cite secondary sources. They tell you the name of the Bureau of Justice study, so let's actually read it. We immediately notice first off that annualized rate of rape for non-college students is 8 per 1000, not 6 per 1000, so they chose the lower figure. Being in college actually *reduces* a woman's rate of being raped. But let's just go with the lower figure. A rate of 6 per thousand over... oh, let's just say 50 years... is 1-(1-0.006)^50=26%. Now, we chose the lesser percentage (6 per 1000 instead of 8 per 1000), and the average woman lives a lot longer than 50 years, but we're again assuming a higher rate of rape in the younger years counters this. In no way does the cited data argue against the fact that one in four women will be raped over the course of their lifetime.

3. I don't know what "Ali's study" is or who Ali is, but it's irrelevant given the above. However, I will point out (and shouldn't have to) that it *is* illegal to have sex with someone who is visibly intoxicated to the point that they cannot make a reasonable decision. I'm not going to dig up the laws on all 50 states for you, but just to pick the largest state, here's California's statute. If the person is slurring their speech and can hardly walk, they're not cogent enough to consent to anything. You can't give *any* legal consent in such a situation. You can't sign over your house, you can't transfer ownership of your car, etc. And that's a damned good thing.

Note that this only applies to cases where the person has drank so much that they are visibly impaired to the point that they can no longer make reasonable judgements. As always with such cases, the courts apply a "reasonable person" standard - they're impaired suchly if a "reasonable person" objectively looking at the situation would judge their decision-making abilities as being that impaired. Being "a little tipsy" or "buzzed" does not meet this standard.

"There are things that are so serious that you can only joke about them" - Heisenberg

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