graycat

132 ms·

841.
by graycat 5y ago
My Ph.D. dissertation was in "Decision Making Under Uncertainty". The topics in the OP are extensive with most of them looking good. E.g., I noticed interpolation -- an old idea but sometimes important. Apparently missing, howe
842.
by graycat 5y ago
Here's some of the story on bypass for jet engines: Yes, high bypass: With a jet engine, what you pay is kinetic energy, and what you get and want is momentum . For mass m and velocity v, the kinetic energy, that costs you (1&#x
843.
by graycat 5y ago
My favorite, long standard spell checker is Aspell long part of a TeX distribution.
844.
by graycat 5y ago
I agree, but I suspect that there is a good chance that a long essay or a short book could provide a lot of that needed learning and growing up. I could contribute several paragraphs of what I wish someone had told me when I was in the f
845.
by graycat 5y ago
My solution to that problem is mostly via my favorite text editor KEDIT and some good directory tree walking via some simple Rexx scripts. So the usual way of working is to use a text window (with a nicely juiced up set of environment var
846.
by graycat 5y ago
Long ago I gave up on letting Windows use associations . So, instead, I run programs ( apps ) via a script that makes the associations I want based on more than just a file extension. Windows keeps thinking that it knows where I want fi
847.
by graycat 5y ago
Yes, there are some challenges in backup and recovery, for ordinary data, for installed programs, for files for an operating system, etc. I'm struggling, don't have good solutions, have a good start, but otherwise have only a work
848.
by graycat 5y ago
> we are just among the first of civilizations ever, Well maybe could say "one of": We recall that the big bang was ~14 billion years ago. Our solar system was made ~5 billion years ago (very rough arithmetic) out of the result
849.
by graycat 5y ago
You make a good point about the conditional probabilities. The article also said "most". There is some relatively good data from Israel, but, still, in practice most doesn't just mean > 50% but is essentially wildly und
850.
by graycat 5y ago
Right. I thought about including that as the aquifers and oil wells dry up, they will have to use solar and/or nuclear power to desalinate the water! Also to get from agriculture as much revenue as they are getting from oil, they wil
851.
by graycat 5y ago
Of course, now Saudi Arabia has changed a lot due to oil revenue and, then, construction of cities, especially near the coast of the Persian Gulf. But in recent years, surprisingly, Saudi Arabia is well into farming! The have borrowed the
852.
by graycat 5y ago
Calculus of variations is, yes, a part of optimization , now regarded as an old part. But subsequent to Bellman's book was the Pontryagin maximum principle . There is an entry at Wikipedia: https://en.wikipedia.org/
853.
by graycat 5y ago
I'd add, R. T. Rockafellar has an interesting technique called scenario aggregation .
854.
by graycat 5y ago
An intro? Nemhauser and Dreyfus and Law are intended as intros and are quite well written. Bellman, who likely should be named the father of dynamic programming, is the oldest book on my list and is not intended as an intro. But if can g
855.
by graycat 5y ago
I might have mentioned that for your example, we can have good confidence in the Markov assumption -- we just say we need to trust the random number generator. In real world practice, i.e., where we don't get to drive the stochastic
856.
by graycat 5y ago
Here are some references for Markov decision theory, stochastic optimal control, stochastic dynamic programming: Dimitri P. Bertsekas, Dynamic Programming: Deterministic and Stochastic Models. George L. Nemhauser, Dynamic Programming.
857.
by graycat 5y ago
So, we are talking about tools. First some generalities: We can expect that considering tools has to be complicated, e.g., apparently the rise of civilization involved the development of many tools for many purposes. Closer to Hacker News,
858.
by graycat 5y ago
Part IV (14) Advanced Calculus This topic is also part of calculus but concentrates on surfaces, volumes, and maybe the math of flows of heat, water, etc. Commonly this part of calculus makes heavy use of vectors and matrices. Also covered
859.
by graycat 5y ago
Part III (8) High School Plane Geometry High school plane geometry contains some nice, useful math and an excellent first lesson in mathematical proofs. (9) Abstract Algebra In grade school, we learned that 2 + 3 = 5 Abstract algebra calls
860.
by graycat 5y ago
Part II (4) Infinity During the days near 1900 struggling with axiomatic set theory, there was also struggling with the concept of infinity or infinite . We say that two sets A and B have the same cardinality , essentially are the same
861.
by graycat 5y ago
Part I I don't believe that an introduction to math has to be long, and here I will try to give an introduction, and overview, just as blog posts. That is this introduction is much shorter than a book. So I introduce the main topics.
862.
by graycat 5y ago
Yes, in math, in the US, maybe anywhere in the world, there is the good and the bad in programs, teachers, books, exercises, etc. So, let's see how to get around the bad: I liked math, a lot. The SAT Math test said I had a lot of tal
863.
by graycat 5y ago
I remember the Argus C3! Lesson: Technology moves ahead and certainly did for photography! We have gone through several steps of astounding. In the 9th grade, to take pictures and be more popular , I wanted a camera. So I went shopping,
864.
by graycat 5y ago
As a ugrad math major, I had some group theory. At the end, I wrote my honors paper on group representations in part to respond to a query from the chemistry department. I got the first dose of group theory in a standard course in abstract
865.
by graycat 5y ago
> In hindsight, I'm not certain if Jeff Bezos 'left well'. Since Bezos is "the richest person in the world" and the founder of Amazon, tough for me to believe he was pushed out; being so rich, he has to have a lo
866.
by graycat 5y ago
I used to live in New York State and, back before the Internet got very powerful, got frequent offers from the NYT to subscribe. I had long since concluded that the NYT was junk, resented the offers, and wrote a scathing denuciating letter
867.
by graycat 5y ago
Yes, I was in IBM, some AI in their Research Division, from 1985 to 1993 when IBM had a big crash. Maybe an old idea I had about PCs has some insight: The idea is that for several years into the rise of the PC , the base, solid as concret
868.
by graycat 5y ago
On several points I agree with the OP on the desirability of "universal computing". For more, I've long thought of most of the concerns in the OP and have not been and still am not much concerned: Why not? === No Smartphone
869.
by graycat 5y ago
No way are we looking at the same pictures.
870.
by graycat 5y ago
There's more on how to harvest, chop, store for the winter, and feed cattle in https://www.youtube.com/watch?v=ucVnbKqvZOw The end of this video shows feeding the silage to a herd of cows. https://www.youtub

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