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Electron band structure in germanium, my ass (2001)

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Re: Electron band structure in germanium, my ass (2001)

#121

Post by entropyie »

don-code wrote: post #87
jerf wrote: post #27

One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopw…

This is, more or less, exactly what happened when I took Electronics I in college. The course was structured in such a way that you could not move on to the next lab assignment until you completed the one before it. You could complete the lab assignments at your own pace. If you failed the lab, you failed the class, regardless of your grade. The second or third lab had us characterize the response of a transistor in…

I ran labs in my university in Europe, in the early 2000s, and I'd like to think this would not have happened. We were selected as tutors due to our proficiency and dedication to the subject. Maybe it was a fluke, I've heard similar stories recently about local Unis.

Re: Electron band structure in germanium, my ass (2001)

#122

Post by shadowgovt »

oddmiral wrote: post #106
shadowgovt wrote: post #62

This reminds me of how the Fahrenheit scale came about. For all its flaws, Fahrenheit was based on some good ideas and firmly grounded in what you could easily measure in the 1720s. A brine solution and body heat are two things you can measure without risking burning or freezing the observer. Even the gradations were intentional: in the original scale, the reference temperatures mapped to 32 and 96, and since those a…

100 + 28 degrees are not harder to mark than 64, and then aim 0 and 100 properly. :-/

What would be the process to do that? To aim 0 and 100 properly, you'd need a tool to calculate a 100:28 (25:7) ratio on an arbitrary distance, wouldn't you?

One can build such a tool, but it's not a doubled-over piece of string.

Re: Electron band structure in germanium, my ass (2001)

#123

Post by robocat »

ALLTaken wrote: post #20
mr_mitm wrote: post #6

Earlier quoted context omitted.

https://pages.cs.wisc.edu/~kovar/cv.html Looks like he went on get a PhD in CS and is now a staff SWE at Google, according to his LinkedIn. Guess he's rolling in cash after all.

You're right, I looked up and he seems to work at Google as a SWE: https://www.linkedin.com/in/lucas-kovar-185a3531 Happy he made the leap and at least get's paid well now (I hope).

The last line seems strangly intelligent:

> I still wouldn't have any women, but at least I'd be rolling in cash.

Did they get a girlfriend?

Re: Electron band structure in germanium, my ass (2001)

#124

Post by Isamu »

orlp wrote: post #99
don-code wrote: post #87

Earlier quoted context omitted.

This is, more or less, exactly what happened when I took Electronics I in college. The course was structured in such a way that you could not move on to the next lab assignment until you completed the one before it. You could complete the lab assignments at your own pace. If you failed the lab, you failed the class, regardless of your grade. The second or third lab had us characterize the response of a transistor in…

What I don't understand is why it took you 8 weeks to distinguish a timer from a transistor. That doesn't make your professor's reaction alright, I just find it puzzling.

Same package. 555 is typically a DIP-8, transistor packages are available in the same. So you would have to examine the cryptic markings and compare them with the other students, and that’s only if you suspected some fuckup on the part of the knowledgeable people.

Re: Electron band structure in germanium, my ass (2001)

#125

Post by DiscourseFan »

selimthegrim wrote: post #107
freedomben wrote: post #97

Earlier quoted context omitted.

That is enraging. I've seen similar things happen too and it blows my mind how ridiculous some of these teachers can be. I don't know if it's dehumanization of their students in their minds or an utter unwillingness to devote 30 seconds of directed attention to understanding the situation and making a reasonable judgment, but whatever the cause it is prolific. The only thing worse is when one of them will add somethi…

Just wait until that teacher is your graduate advisor.

I hear so many horror stories in the sciences, I have no idea why anyone would pursue an academic career in it.

Re: Electron band structure in germanium, my ass (2001)

#126

Post by mercutio2 »

mizzao wrote: post #88
BeetleB wrote: post #85

Oh, BTW, the whole "Friction is directly proportional to the normal force": My Ass! I could never reproduce it well in the lab, because it's really not true. Take a heavy cube the shape of a book. Orient it so that the spine is on the floor. It's a lot more friction to move it in one direction than in the transverse direction. Yet the normal force is the same. Any kid knows this, and I feel dumb it never occurred to…

Is this possibly because you need to use additional force to horizontally stabilize it in one direction (perpendicular to the spine) but not the other?

I was about to say exactly this.

Applying force directly to the center of gravity with one finger is hard.

You end up applying torque plus adjustments in response to that torque. And that is heavily dependent on your moment of inertia, unlike the normal force.

But I do agree that explanations of friction are right up there with “how do airfoils work” where poor instructors are liable to get long past the edge of their knowledge and just make shit up.

Re: Electron band structure in germanium, my ass (2001)

#127

Post by homeless_engi »

CamperBob2 wrote: post #89
don-code wrote: post #87

Earlier quoted context omitted.

This is, more or less, exactly what happened when I took Electronics I in college. The course was structured in such a way that you could not move on to the next lab assignment until you completed the one before it. You could complete the lab assignments at your own pace. If you failed the lab, you failed the class, regardless of your grade. The second or third lab had us characterize the response of a transistor in…

Honestly, you got more real-world electronics training out of that experience than you paid for. You are now qualified to deal with remarked or counterfeit Chinese parts and other inevitable supply hazards in the business. Be grateful!

Yes, maybe true. But it's a pity that was not reflected in their final grade.

Re: Electron band structure in germanium, my ass (2001)

#128

Post by wholinator2 »

HiPHInch wrote: post #11

I took some effort to change my research interest from computer vision to DFT calculation in quantum chemistry. Honestly, I'm kind of frustrated now, too many work is close-source in this area. The research paper will tell you everything except how to reproduce this work in minimal effort, it's like they are hiding something. They also using a `Origin` to plot and MS Word to write paper, which is also non-free licens…

Very true that they're hiding things. I actually wrote some code (that strung together other people's code) to complete a simulation pipeline for non adiabatic molecular dynamics. I was tasked with writing documentation to teach the group but was instructed to not release it anywhere publicly because other groups would simply take the method and move faster since they had more money and compute.

Re: Electron band structure in germanium, my ass (2001)

#129

Post by npongratz »

sio8ohPi wrote: post #91
npongratz wrote: post #50

Earlier quoted context omitted.

> From grade school on, you are graded on whether or not the grading authority likes the results you got. I took an exam in a high school science class where I answered a question with the textbook's definition exactly as presented in the textbook, complete with the page number the definition was found on. I knew a bit about the topic, so I then cited outside scientific sources that explained why the definition was i…

Having been on the other side of the table... there's a tactic students will sometimes use, where they don't understand the question but will simply attempt to regurgitate everything written on their notecard that is related in hopes that they'll accidentally say the right words. Sounds like you did understand it, but the volume perhaps made it look like you were just dumping. It is indeed annoying to grade. Grading…

Sure, we could speculate about his true unstated reasons for marking wrong my answer.

I highly doubt the science teacher marked me wrong for "dumping", though. He had every opportunity to explain that to me after I got my exam graded and I asked him about it. Then he had the opportunity to explain that face-to-face with my parents. He did not do so. He said that while I got the answer right, he was "mad", thus the mark against.

Besides, notecards were not allowed for any part of the exam, and I wrote my answer from memory. I think it was clear that I knew my stuff pretty well and was not "dumping" a bunch of bullshit onto the science teacher.

There was no indication before taking the exam that I would be punished for hurting his apparently-sensitive feelings while giving the correct answer (as he agreed I did). If there were, I certainly would have chosen a different medium for proving my command of the material.

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