Believe-me, it is painful, for a guy that is the son of a writer, and often judged as having an elegant writing in his language, to find himself helpless as a child in a foreign language, when it comes to passing subtle nuances of humor, irony, second degree, or simply of being able to play with words in a slightly delicate way.
The lack of elegance and subtlety often goes for an aggressive attitude, how to dress elegantly when one lacks fabrics ?
And I often wonder why American and English people do not speak French like everybody else ?
I'd vote for Chinese ;-)
But your point of lacking elegance and even the risk of severe misinterpretations of one's intents is certainly true. OTOH, just like DF96 says, some people don't care about the way they present themselves anyway, no matter what their toungue is.
But your point of lacking elegance and even the risk of severe misinterpretations of one's intents is certainly true. OTOH, just like DF96 says, some people don't care about the way they present themselves anyway, no matter what their toungue is.
But let us come back to the topic.
(En Français "Revenons à nos moutons.")
Some new advances in the sound of cables ? Some decisive victories in the war against snake oil manufacturers ?
(Smiley here)
(En Français "Revenons à nos moutons.")
Some new advances in the sound of cables ? Some decisive victories in the war against snake oil manufacturers ?
(Smiley here)
Fly on the wall.....
Ok,we're ready, push the switch...
Uh uh, not me...you push the switch..
No way, I'm not pushing it.. Hey, let's have Mikey push it.... He'll push anything...
Jn
Shamelessly stolen from an old tv commercial many of you are too young to have seen.
Here is a book that I thought both JN and I could agree on. I got it through Amazon for a reasonable price, and it is sufficiently detailed enough to actually attempt to be accurate in the physics of devices. It would be a bit too much for most here, but it could still serve you in understanding the true complexity of electron flow, etc. rather than the simplistic models usually shown techs and engineers alike in order to have something to work with. True understanding is more difficult, however.
Actually, reading through a book like this can be truly humbling, and that is a good thing, sometimes.
Actually, reading through a book like this can be truly humbling, and that is a good thing, sometimes.
Attachments
What I don't get is that, if they were expecting 700T why was the containment only designed for that? Haven't they seen Jurassic park? Or was this the first time the team had hit the stretch goals?
T, you convey your ideas very well, especially when English is not your first language. Yes, we Americans are very bad with languages. Of course, I took a little French in college, and I did live in the French speaking part of Suisse for several years, but I was always surrounded by English speaking people, and the Swiss would always turn to English as soon as I started speaking my poor French, in order to show their 'superiority' in languages. Unfortunately, for the last year there, I let my wife, (a violinist from the institute that I had worked at) do the daily shopping, and interaction with the public, so now I can barely read a technical article in French. French is a beautiful language, but one has to be immersed in it to keep it, if you never learned it as a child.
By the way, your spelling while sometimes slightly off, is still very close, and is completely understandable.
By the way, your spelling while sometimes slightly off, is still very close, and is completely understandable.
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I have his fifth edition. I will admit, I've never referred to his chapter on superconductivity since I started work here. A few of my friends can so easily explain it compared to reading it in the book.
From the cheap seats, I vote incompetence. The size of the field is in the nanometer range, so it doesn't matter if there was 700 or 7000 tesla.
Rather, they pumped 3.2 megajoules into the coilset. So, they should have designed the chamber to support that level of explosion, the magfield did not add to the energy, they knew the exact amount of energy to deal with.
The other thing I can think of, is during the collapse, the energy released asymmetrically, so destroyed the chamber by a directional blast wave. That would have been a pants down episode, but not incompetent..
That said, a lot was learned by them, and it's good nobody was hurt.
jn
John,
Have you at least skimmed through this book? Some of us had to study and pass several tough exams based on this (and other on the same topic) book.
I myself can certify that any book on this topic (and this one in particular) has nothing to do with wire directionality. Au contraire, the microscopic (quantum) theory of conduction in crystals shows exactly why there's no good reason for wires to be directional.
I agree with others, this showcase of books that you actually never went beyond (perhaps) the introduction doesn't do anything good for your reputation.
I have a jewelers lathe, a 7 by 16 mini, am totally longing for a mini milling machine, and am building a micro wire EDM for cutting watch and clock gears and parts. I suspect the EDM will probably take a decade for me to finish it, I keep getting sidetracked. The mini milling machine, I will probably pull the trigger if the tariffs are dropped. Seems every mini lathe and milling machine are made in china in the same factory. I got bit for 250 dollars on the lathe, would prefer to not repeat that.
j
While I certainly agree with you, syn08 also hits the nail on the head. Nothing in the book supports conductivity directionality, nor burn in. To try and shoehorn what he wrote to try to fit what we observe with bog standard instruments won't get us anywhere.
The fifth edition is my textbook from undergrad. I just glanced through the chapter on superconductivity, it's so cool actually seeing in the book, and working with that stuff.
All of the funky quantum stuff being used to try to explain what we do at room temperature with standard materials is a simple mis-application of information. Everything you, Ed, me, Scott...measure, has far simpler explanations than needing to hit Kittel. No matter what any of us think, we are being bit by test methodology and experimental design.
These reference book topics are best used over at the nanomaterial department, and for the most part, it would be used to try to give people like us a simplistic explanation of what they do. As, we "can't handle the truth"...
That said, I do appreciate your reach out.
Do you have the time to mentor undergrads at Berkeley? I suspect analog circuit theory would be well received there. Maybe you could set it up in a "challenge" format.
jn
Containment of mag fields has always been difficult. The slightest of asym will become the weak point. I am sure they tried for sym but at the fields produced, just wasnt good enough. When it is good enough, they can go higher but then a new weak spot occures. ETC. It is a fundemental problem that has always prevented the experiments to reach the level all have been looking for and have been attempting. For example, can we reach the level needed to cause sufficient compression to create ignition and sustain a plasma? --- without severe leakage and/or tearing the machine apart? Probably not. So, we went to laser.
THx-RNMarsh
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Try a Taig micro mill (made in USA), the ball screw version. Comes with 0.5 mil repeatability out of the box, and can be further tuned down if you decide to replace the ball nuts with double ball nuts. That's what I'm using, with a self built stepper controller and a PC running MACH3. I also replaced the stock motor with a VFA driven spindle with ER16, goes up to 24,000rpm, great for milling aluminum, copper, brass with a 10mil carbide end mill (with very slow feed though).
The Chinese gantry type routers (sometime sold as "mills") are pure junk, impossible to fix/adjust, don't even think about. They are good for woodworkers, at best. The only decent Chinese CNC mills that I know of are the Syl machines, but then in my opinion they are not that cheap to compete with the US made equivalent class machines (e.g. Tormach).
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No, I mentored an engineering professor at UC Berkeley once, does that count? Got paid for it too!
I did mentor an undergraduate Berkeley student while he worked for me, back in 1977. He got his degree, moved on to Ampex, (we shared the same boss, but different years) then to Sony, and then to even more interesting assignments in Silicon Valley. He was at the Analog A party just a week ago. He is now writing yet another textbook on electronic design, and teaches at Stanford University. He is very busy.
Kittel's stuff (and that's accepting my utter weakness once you hit Green's functions, also known as everything in solid state physics) is much more straightforward than "why am I getting *that* result from this test?"
*If it does work according to plan, I didn't try hard enough.
I wanted work to get a used Datron (their smallest model, can't remember the name). Big compared to something like the Tormach 400 series, but not much bigger than the 1100 for how much more work envelope and capability it brings. We have a mini mill (Minitech) which is tuned for microfluidics (<1um TIR and 10 um repeatability), but we've gone purely with patterned and etched silicon masters for casting PDMS parts. And it's super frustrating trying to hog out brackets and anything *not* requiring micron-sized tooling/cuts.
This rant may be inspired heavily by the fact that I spent half a day unsuccessfully trying to get Mach3 fixed after our automatic IT software updates.
Agreed on the gantry routers. But even for wood they have too much flex.
I like the fact that the wire edm produces no tip forces, so accuracy during microstepping will be the friction of the recirc balls on the rails and the ball screw.
I picked up a usb controller mk3/4 to play with, and a bunch of steppers and DQ542MA drivers along with 10 arduino's and one display.
jn
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