You're talking about different things. A slow FET has a slow rise time. It spends more time crossing through the inefficient region between fully off and fully on. Switching frequency is how often you cross in one direction.

Up to a point, you can decrease total converter loss by trading conduction loss for switching loss by increasing frequency and resizing components. After that point, you start losing efficiency again. There's a sweet spot.

thanks for addressing things with far more patience than i would have.

Yes, I see your nickname. That's the case if we go into details.

I think he specifically means high-end, high-frequency power FETs, since all the rage today is about them.

I would add that there is no real need for super-high-end switches in EVs, and component size for them is not a huge premium. There is no shortage of smart inverter topologies which achieve very good size, and efficiency without using any kind of fancy GaN of SiC switches. They will not be as small as them on the lower end, but around 100kw there is virtually no difference.

It's not a detail. It's a more complete picture. Both of your comments are different slices of the same pie.

I don't see anything written above that pertains specifically to any type of FET.

Your last paragraph is a new topic. It's true that Si can be as efficient as SiC and GaN, despite what the marketing usually says. But there are other benefits to new materials. They already support higher voltages with planar technology, and 3D will increase that further. Gate driving will get easier and more rugged.

> Your last paragraph is a new topic. It's true that Si can be as efficient as SiC and GaN, despite what the marketing usually says. But there are other benefits to new materials. They already support higher voltages with planar technology, and 3D will increase that further. Gate driving will get easier and more rugged.

There are 1000V+ silicon switches today which are not as fast, but have for, for example, very good RDSon. 1000V I think is an upper limit one would go for passenger car EV motors.

True, but even GaN will eventually exceed that, and there are other applications that will benefit.

> the outcome of the meeting as far as I understood it was, what can Microsoft do to help?

Here's the problem. That's sales talk. If you're not buying, either give your sales pitch or quote them for consulting.

It's the US Space and Rocket Center for anyone looking it up. The vertical rocket is a replica. The sideways one is real, or mostly real. It's suspended pretty high up so you can walk below it. They host a weekly Oktoberfest event under it for a few months a year. In addition to the museum, they also give bus tours of NASA MSFC.

There's a planetarium nearby with a cool history made from the dome of an oxygen tank. UAH has a special collections room dedicated to the Apollo program. There are some other rockets on the side of the interstate near the outskirts to let you know you're entering rocket city.

If you plan carefully, you can see everything in a day.

Change your search strategy. Most forums require a membership to view them, and most long form posts are on personal websites. Google can't or won't serve those. You have to navigate like it's the old web. Find a good place to make landfall, read old posts, ask around, and follow all your leads.

C# is a well-regarded choice for the application layer in the engineering software world. You'd need a good reason not to choose it.

I briefly worked in one of the statistically worst states for bicycle safety, but I was still surprised to learn how many older people fantasized about running over cyclists, or had a "they probably deserved it" attitude whenever a cyclist was struck by a car.

One time, a couple of coworkers were riding single file in the generous shoulder of a wide nearly empty multi-lane road in the early morning when they were both run over from behind in a hit and run. One had to have his spine fused. I still saw the same attitude of contempt, even from coworkers who otherwise liked them.

I switched to mountain biking after that.

Strange really - I've never figured what that's all about, speaking as a driver who has no problem with cyclists.

It's a culture war topic.

Ah. Not seen so much of that in London though in the comments section of the Daily Mail some people rant about cyclists. Guess it's more seeing them as an enemy tribe rather than them actually cluttering the road. In London the bigger aggression issue I've seen is cyclists having a go at pedestrians which also puzzles me a bit if less so.

Imagine learning to code again. You're shown one for loop, a class header file, and a cartoon of a data structure. You write programs by hand on paper, submit them, and never get any feedback. And you're forbidden from looking at open source code. Some amount of struggle and self validation is fine, but unnecessarily wasting absolutely all your time on dead ends is a waste.

This type of bullshit is normal in crappy STEM classes. Universities are so concerned with keeping secrets that they won't give you the information in the first place. It's a sign of bad course design that's unfortunately common.

I took a couple classes that were like that, but I swapped the class for another subject those semesters and waited until it was offered again by a better professor. Same material, except I actually learned it instead of getting stuck at the starting gate.

I'm certain they grade homework and return it.

Right, but at the pace that many of these courses go, and with how the material continually builds throughout the semester, not getting answers until a week after the quiz, and hence two weeks after the lecture taught the material, is setting up a lot of people for failure.

By having access to multiple worked examples of problems, students at least have a fighting chance of learning how to solve problems _in parallel_ with the course material, rather than having to wait days or weeks to even know what they did wrong, while getting more and more lost.

Remember, these are Princeton students, some of the most brilliant and motivated minds of their generation, and the averages are _abysmal_. That indicates there's a greater systemic issue.

I had an organic chemistry professor who would not return anything until the end of the semester, homework, quizzes, test, nothing. I had the impression she was a procratsinator and just didn't do the work. It was beyond frustrating. She also got her ph.d from Princeton coincidentally!

I did this at Loyola New Orleans (an intro physics lab class) and I'll tell you why. I didn't trust the kids to not lose their work. They could come to my office and collect it and if they challenged their grade, I had all the material to hand with me. Online reports were graded on Canvas at any rate.

You made your class educationally worse and blame the students because you didn't ask for a photo of their work?

Canvas had photos of it online - you misunderstand.

> I did this

Glad to hear you didn't actually do that. Returning digitally is still returning.

One reason for not returning work immediately is it makes it harder to accept late work, because students will share the answers with each other.

The most lenient late policy I've experienced in my (ongoing) university experience has been that you can submit 1 day late for a 30% penalty. Most of my classes lock the dropbox immediately at midnight.

Simply returning work shortly after the late work window closes should suffice, no?

I respectfully disagree. Learning mathematics is just as much a craft as learning an instrument, or how to paint, or how to write prose, or how to layout a PCB; it requires a lot of hard work, but if you're consistent AND have the right tools, you can learn it just like any other subject.

Believe it or not, the number of practicing mathematicians and PhD students who have the innate grasp that a Terry Tao does are few and far between. The vast majority have to work hard to earn their skill.

Note that the contradictions you mention are _physical_ in nature; it is true that there are some functions that some bodies can perform that others cannot. Mathematics is not one of those things.

Is the brain not a physical thing? Do you believe that all human brains are physically and functionally equivalent such that one brain should be able to learn to do anything that another can?

What about those people in this world with genetic abnormalities that affect brain function? Would you expect someone with Prader-Willi syndrome to be able to become competent at mathematics if they only worked hard enough at it? At what point does “hard enough” become “virtually impossible” or even “definitely impossible”?

> Is the brain not a physical thing?

Why, sure - from the physics standpoint all the human brains are essentially the same, they all consist of the same protons, neutrons, electrons... (Also, they are close enough to being spherical.)

While I feel your point is incredibly pedantic, perhaps I should have qualified with some form of "at least X% of people that do not have rare genetic disorders can learn math, X >> 50". However, I think such statements are usually implicit when talking in generalities.

Got it. Your previous statement didn't really seem like you were speaking in broad generalities and instead seemed more absolute, like math is something that could always be learned by any human brain. Clearly that's not the case, which was the point of gpp, I think.

People have wildly different personalities and creative abilities. why do people think the "math part of the brain" is exactly the same in everyone?

> University level mathematics requires a level of abstract thinking that most people are simply incapable of

You're begging the question. Please substantiate.

You might be surprised. My daughter took first year university linear algebra last year and graded assignments and tests were often returned weeks later, in some cases well into the exam preparation period. I told her this was unacceptable and she should complain, but you can imagine why a young, shy first year student might not be able to get over that potential barrier.

> you can imagine why a young, shy first year student might not be able to get over that potential barrier.

If she continues on to functional analysis she can just tunnel through.

Another thing that one might not have considered is the perception of women and math. Of course your daughter might not want to protest against unfair mathematics teaching structures given that her struggle is societally used to represent that all women struggle at math. <relevant xkcd comic here>. I would also hesitate to protest unfair practices in situations where I was a minority because I know anything short of quietly excelling is a negative representation of my entire demographic.

this is an exceptionally bad take imo and seems extremely degrading towards women

Grading the homework is not the same thing as providing feedback. A big red X tells you that something is wrong, but not what you can do to fix the problem or even why that thing is wrong.

Okay, so go to office hours or a math center (if available, apparently quite common).

I certainly don't want to be misquoted as claiming that mathematics must be learned in a vacuum. Just that access to a large collection of questions and answers is not helpful. Your own argument goes through just as well to show that access to the answer isn't helpful either: you know you got the wrong answer but you don't know why.

Sure, you can do that. But from a UX perspective, the system is clearly badly designed.

For proof based homework typically a grader will tell you which step failed with a short note saying why ("this mapping is not well defined", "here is a counterexample", etc)

It is cryptic at times bit ultimately developing rigor and intuition is something that in my experience will always involve a certain amount of struggle and confusion that no professor can or should alleviate

My university certainly didn't in most cases.

Imagine having to size up the other vehicles before crossing a bridge instead of just worrying about yourself.

Like playing the "guess your weight" game with everyone else piling into an elevator

Btw, 1 ton = 2000 lbs, not 1000.

The real reason is to stimulate the national electrification capability by increasing the demand. This article is just typical marketing.