I meant *this* planetary system, Earth, specifically its atmosphere and climate. Agree, and have said elsewhere, that the solar system is pretty damned regular, nicely periodic, and is only weakly chaotic.
Systems simulation is a big piece of electronics, and most to the systems we simulate are tractable enough the the sims are useful. But other system, like the stock market, aren't as nice.
Lots of effort has been put into simulating the stock market. It's chaotic at a meta-level: if anybody ever did come up with a useful simulation (which is probably impossible anyhow) that was consistantly profitable for small-scale, under-the-radar investments, pretty soom everybody would be using it, and they would all be bidding against one another in a zero-sum game, so *that* higher level process would collapse into chaos. Cool.
Tell me about it, I've got this little thermal thing. (heating a cubic inch glass cell) We've shipped about 100 and I've got ~5 'bad' heater/cells on my shelf. It's some marginal design that works... mostly. I've tried several 'bandaides' some of which worked... but they're all 'bandaides' and ugly.
And giving John "dupnik" Larkin a _forum_. ...Jim Thompson
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I love to cook with wine. Sometimes I even put it in the food.
Respond with substance, and I'll reply that way. You seem to have no opinions about simulation, the validity of simulation, or chaotic systems, but get worked up when other people do. It's a funny discussion group where some people discuss real issues, and other people only whine about it.
Most electronic systems simulate pretty well, at least if you set them up right. So we don't encounter chaotic systems much. If we did, we'd avoid them.
I wonder if a superregen qualifies as a chaotic system. It *looks* chaotic, but that's not inherent in its dynamics without noise. It sort of resembles an inverted pendulum, a classic chaotic system example.
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Yes, but with respect to your posting history, you refer to your
detractors, disparagingly, as clucking hens or gossipping old ladies,
both of which cast aspersion on femaleness by attributuing to them
negative qualities "typical" of females, from your point of view.
When you and Jim, the only real hens in the group, cluck and gossip, it's on target. Neither of you contributes to the topics very much. Being stupid, whining old farts is, at your ages, still voluntary.
Wrong. Check the posts.
It's more likely that you don't have opinions.
Most of your posted sims have been wrong the first time, and often the second. I can see how you'd rather cluck than discuss simulation. Or check your work.
I understand how it works as a detector. Do you?
I was wondering "if a superregen qualifies as a chaotic system." What's your opinion on that?
So, you had an educational advantage over less fortunate people in the world? Your parents were educated and helped you along the way? How does that relate to your socialist view of the world, where everyone is equal?
Socialism doesn't preach that everybody is equal. It does espouse the idea that everybody should have an equal chance to exploit their - differing - talents.
Kids whose parents have been through the tertiary education system are more likely to go to university for all sorts of reasons, and they tend to do better than their colleagues whose parents didn't have that advantage.
From the point of view of the efficient use of resources, it makes sense to send people to university who are most likely to complete their degree courses and to complete them in the minimum time.
When I was at university in Australia in the 1960's about 30% of students made it through their undergratuate courses in the minimum time. Another 30% took an extra year or two to make it and 40% dropped out.
Kids from working class backgrounds were under-represented at university, and those that had made it tended to have been persuaded by their teachers against the wishes and expectations of their parents. At the time very few Australian aborginal children made it to university - aboriginal culture doesn't include uniiversities.
At that time. pretty much anybody who did well at secondary school could get a Commonwealth Scholarship, which paid your tution fees, and
- if your parents were indigent - a living allowance. Your parents had to be dirt poor before you could get a living allowance - if you could demonstrate that you'd been self-supporitng for three years, their income fell out of the picture, but that was rarely practical. My wife
- and a number of my friends - had to take an Education Department Studentship to pay for their education, which meant that they had to teach for three years after they graduated. In her - exceptional - case, she was allowed to work out her bond by teaching at university.
One of my nephews did manage prove that he had been self-supporting for the first three years of his course and got the Commonwealth living allowance for the fourth year of his university studies, much to the amusement of my brother, who was - and is - extremely well-off.
I didn't get to university because because my parents were educated. That they were educated helped me in any number of ways, but the decisive fact was that I did well as school.
The guy that I - mostly - just beat out for the top of the class didn't have the advantage of tertiary edicated parents, but he too went to university (in Hobart) and got a Ph.D. in Chemistry. Since he's now Professor of Inorganic Chemistry at Meobourne University, he clearly has done better than I've done.
I really hate it when we do something that works but we don't understand why. In a physical system, like your glass cell, you have better excuses than we do in a circuit.
Many of the "don't understand why" fixes are to add a capacitor. We did that to a diffamp recently, to stop oscillations that we really thought shouldn't be there. Time before that, a couple of months ago, bypassing some precision resistors in an RTD circuit made a nonlinearity go away, reason unknown. And there was that FPGA that wouldn't configure consistantly without a scope probe, or a cap, on CCLK to ground, even though the waveforms looked perfect.
Yup, I find that if I've made some fix, but didn't spend a bit of time to figure out why it worked, then inevitably it will come back and bite me again in the future.
Yup, The Rb cell temp wants to be up near 45 C (or higher sometimes). The thermal design is a bit convoluted. (And not all that well understood.) There's a cold finger around the tip of the Rb cell. And heat is applied near the cell windows. We don't want any Rb on the windows. The prototype and first ~ 70 units all were fine. Then a year or so ago I found one that didn't work that well, there was always a bit of Rb down the bottom of the window (where it's coldest.) Since then I've had a few more rejects, these have gone on a shelf and now I'm 'playing' with them. I thought I might post some pictures and solicit advice from the group if I don't like the latest 'fix'.
I fixed one of them today! The hole where the coldfinger touches the glass was 'off center'. That's at least part of the problem. (Make hole bigger and on center.) I'll have to write, some newsletter blurb. Ever instrument is a bit different. A cell comes from here, coils wound there, foam hole a bit off center. It's hard to know where to look for the problem.
Yes, at university level I would agree. But most of the damage is done in the early years where good students are handicapped by uneducated parents and the school system. We've tried many socialist ideas here in the states designed to level the educational playing field, that didn't work. We had affirmative action to help some go to better schools and failed. Texas tried to spend a billion improving school facilities that also failed. And there have been several "Voucher" proposals, all defeated, designed to help a few marginal income families escape the failing public school system through tax credits. The public school system here fails at the lower level due to a few un-manageable students that just want to disrupt the class and cause trouble for others. And the system will not allow the expulsion of trouble makers. You almost have to carry a gun to attend the public schools here in California.
I've seen the relevant episodes of "The Wire" that dramatised that particular problem, and also made it clear why your "socialist" initiatives seem to be bound to fail.
Everybody in the Baltimore system seemed to be concentrated on their short term advantage, rather than considering how the outcomes for the kids involved could be improved.
"The Wire" - at several points - illustrated the way in which - manipulated - statistics would be come more important than the reality that the statistics had been developed to illuminate, in much the same way that cultivating short term profit has come to replace the development of useful and sustainable industries and services.
But the more of them you look at, the faster you'll find the problem. After about a hundred I predict that you will start making your own, and they will be much more reliable. Granting a spot of genius on your part, they may also be cheaper.
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