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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)

#221

Post by shadowgovt »

oddmiral wrote: post #210
shadowgovt wrote: post #122

Earlier quoted context omitted.

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.

Make marks on the thermometer at 0 and 100 degrees C, then project light from a candle to a wall to see these marks with say 5x magnification. Now project marks from the 128 mark ruler to the same wall and align marks from both, then place marks on the thermometer with 5x better accuracy.

Sounds doable, but again, you're comparing that approach to:

- get some string

- measure a length between your low and high points

- fold it in half

- make a mark at the halfway point of the string

- fold it in half again, etc.

No candles, projection, transparent or slotted ruler, wall, or carefully moving one's hand back and forth under projected magnification needed. Just some string.

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

#222

Post by don-code »

cycomanic wrote: post #208
Isamu wrote: post #124

Earlier quoted context omitted.

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.

But that's the thing that both students and often the teachers forget. We don't run labs to go smoothly, we run labs because you'll have to troubleshoot. There is no learning experience in a lab that works without issues, in fact IMO if lab instructions are of the step by step type, they should always have some deliberate errors in it to get students to troubleshoot. To play devil's advocate, just imagine the previou…

If after eight weeks a junior engineer is still toiling on their story, I'd ask why someone more senior didn't get involved.

There are lots of reasons - maybe the senior engineers are overburdened with other work (or don't care), maybe the project manager or team lead wasn't asking if the junior needed help, or maybe the junior was lying about their progress.

Either way, a story that goes for eight weeks feels excessive. Much, to your point, taking eight weeks to figure out that there was a bad part feels excessive. My counterpoint is that teams don't typically operate like labs. In a college lab, the objective is for you, specifically, to succeed. In an engineering team, the objective is for the entire team to succeed. That means the more senior engineers are expected to help the more junior engineers. They might directly coach, or they might write better documentation. I don't believe that dynamic is present in a lab setting.

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

#223

Post by capitainenemo »

matheusmoreira wrote: post #65
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…

https://v.cx/2010/04/feynman-brazil-education > Then I held up the elementary physics textbook they were using. > There are no experimental results mentioned anywhere in this book, except in one place where there is a ball, rolling down an inclined plane, in which it says how far the ball got after one second, two seconds, three seconds, and so on. > The numbers have ‘errors’ in them – that is, if you look at them, y…

Interesting. If that is correct and you take OPs value, 6.8 / 5 * 7 = 9.5 which is pretty damn close. So his failed grade was for the only non-cheated result?

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

#224

Post by selimthegrim »

karel-3d wrote: post #211
DiscourseFan wrote: post #125

Earlier quoted context omitted.

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

Well in the industry you have the weekly JIRA humiliation rituals, bad things are everywhere

[flagged]

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

#225

Post by rlpb »

cycomanic wrote: post #208
Isamu wrote: post #124

Earlier quoted context omitted.

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.

But that's the thing that both students and often the teachers forget. We don't run labs to go smoothly, we run labs because you'll have to troubleshoot. There is no learning experience in a lab that works without issues, in fact IMO if lab instructions are of the step by step type, they should always have some deliberate errors in it to get students to troubleshoot. To play devil's advocate, just imagine the previou…

For a college class grade, everyone is supposed to be tested on the same exercise. If all students were tested under the same scenario then it would be fair. For just one student to be tested under this scenario, but for all other students to get a free pass on the lab component identification diagnostic test, is not reasonable.

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

#226

Post by qwezxcrty »

prennert wrote: post #95
qwezxcrty wrote: post #25

Earlier quoted context omitted.

I miss OriginPro in my undergrad when we had campus licenses for, before moving to matplotlib for data visualization. matplotlib is simply too disappointing for making publication quality figures. The most recently encountered problem is how to plot with a broken x-axis, which is one of the most basic need in physical science but requires a non-trivial amount of hacking to get with matplotlib. Open source tool or not…

Matplotlib is a bit painful. Often seaborn will work quicker, especially when using Pandas dataframes with proper column names and seaborn compatible layout. Its annoying that you cannot create a broken axis out-of-the box, but I am sure you can wrap this to make your own convenience function: https://matplotlib.org/stable/gallery/subplots_axes_and_figu...

That link was what I referred to after Googling, but in my case I need the width of the left part and the right part to be different, which requires setting width_ratios in the subplots and adjusting the slope of the hacky lines used to draw the broken axis symbol. seaborn also would not help in this exact case.

There is a package by some nice guy: https://github.com/bendichter/brokenaxes just to do the broken axis. But not being built-in in Anaconda is already an annoyance, and in my case it generates a figure with a ugly x-label.

I ended up letting ChatGPT generate the code for me with the two required hacks. I simply need the figure in the minimal amount of time and with the least mental bandwidth, so I can focus on the science and catch the conference deadline. Origin is a very "over-engineered" piece of software, but hey getting a broken axis is so simple (https://www.originlab.com/doc/Origin-Help/AxesRef-Breaks ). Sometimes the "over-engineering" is necessary to minimize users' pain.

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

#227

Post by thaumasiotes »

kirubakaran wrote: post #213
realo wrote: post #151

Earlier quoted context omitted.

ALWAYS suspect some fuckup on the part of the knowledgeable people... especially them! Trust, but verify.

"Trust, but verify" is just a polite (ie corporate) way of saying "Don't trust until you verify", right?

No, it says that projects should move forward without verifying that prerequisites have been fulfilled, but that the verification should take place anyway. It's about the pace at which you can go.

Trust-free:

    Ensure that step A can go off without a hitch.
    Begin step A.
    Ensure that step B can go off without a hitch.
    Begin step B.
    Ensure that step C can go off without a hitch.
    Begin step C.
Trust, but verify:

    Begin step A.
    Begin step B.            Check that you have whatever you need for step A.
    Begin step C.            Check that you have whatever you need for step B.
                             Check that you have whatever you need for step C.
You can't finish step B until you have all the prerequisites, but you can start it.

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

#228

Post by sevensor »

dvh wrote: post #133
sevensor wrote: post #76

I TAd a semiconductor fabrication lab class 20-odd years ago. Mostly it was about making sure the students had the absolute fear of God put into them about working with HF, but there was also a bit at the end where you actually got to do a voltage sweep and characterize your transistor. If in fact you had made a transistor rather than a needlessly complicated resistor. The other TAs and I passed this paper around and…

And then there are Etsy moms making frosted shot glass

I would make them reread the MSDS.

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

#229

Post by mvieira38 »

qwezxcrty wrote: post #25
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…

I miss OriginPro in my undergrad when we had campus licenses for, before moving to matplotlib for data visualization. matplotlib is simply too disappointing for making publication quality figures. The most recently encountered problem is how to plot with a broken x-axis, which is one of the most basic need in physical science but requires a non-trivial amount of hacking to get with matplotlib. Open source tool or not…

Honestly, if you're doing scientific work there is no reason not to output the data somewhere and plot in R with the standard lib (insanely good for science style plotting but hard to use) or ggplot (what matplotlib wished it was)
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