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OldChemE

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Everything posted by OldChemE

  1. I believe the main issue with the broad definition is that it makes the problem more easily discounted or ignored ("What, 6 in 10?? politics!")
  2. The parent is not the customer. The Student is the customer. The whole purpose of education is to better a person's life, and that person is the student.
  3. Recently,my wife was in the hospital recovering from an operation, and her blood pressure was very low-- so the doctor kept her in for observation. I noticed that the automatic blood pressure monitoring system showed not only the systolic and diastolic values, but a value labeled "mean." However, from the numbers it was clear that there was some sort of algorithm involved, as the third number was not a simple average. I asked the Nurse the meaning of the value and she told me it was a measure of "stable" blood flow in organs, and the goal was to stay above 60 to avoid medical problems for some organs. Totally new concept to me, but it suggests the two pressures (S and D) have a more fundamental relationship that is desirable.
  4. There is still disagreement among geneticists on this. You can research it on the internet, and you will find that some geneticists believe it is genetic but suffers from "incomplete penetrance" which is a situation where not all those who have a gene can express it.
  5. Actually, until I retired from teaching a few years ago, writing in class was exactly what seemed to work best for teaching (at least for me). I was teaching Math. Instead of lecturing all during class and then having the math done as homework, I gave reading assignments for homework, then a quick review and had the students work their math assignments in class (on paper). This seemed to generate many discussions on best methods of solving problems, as well as ensuring the students had well-focused practice in solving problems. It also encouraged students to compare answers and self-correct, which is itself a good learning experience.
  6. Certainly. Fairly simple organic chemistry. I've got an organic chemistry textbook on my bookshelf that covers how ("VOGEL") but I'm away from home at the moment so I cannot quote the method. The real question is why? Fermentation is simple, inexpensive and allows one to tailor the alcoholic beverage taste to suit the drinker's preferences.
  7. How to assess abilities? The best way is to not rely on anything that can be generated via the internet, That's why, in math classes for example, the gold standard has been pencil and paper and "Show your work"
  8. You may not have fully understood one of the subtle points of Exchemist. He mentions compressible and incompressible fluids. With water, when the diaphragm moves it creates an instant large pressure change because the water cannot compress or expand. This is what gives good flow. With a gas, when the diaphragm moves the gas simply expands or contacts to fill the space, and you get a significantly smaller pressure change. This is the fundamental problem with trying to use a diaphragm pump to move gasses. It doesn't man it won't work, but the efficiency will be poor compared to pumping water.
  9. Certainly there are creators and those created by them, but the physical evidence seems to show that the religious have the identities reversed.
  10. At one time, back in the 60's, I learned to program computers in machine language, and I delighted in the fact that I could actually know, step by step, how the computer was performing its operations. Since then we have reached the stage in technology where the actual operations performed by the computer are complete buried in layers of code-- and the performance is vastly enhanced. Sure-- someone who knows a lot about the esoteric details might conclude that IEEE 754 was not the best approach. BUT its the one that things are built on. What you have in in the linked article is someone who sees the inefficiencies in the "wheel of choice" and wants to re-invent the wheel. The question is, can they demonstrate a financial and sociological benefit to the user of computation devices to make the change. "This is better" doesn't cut it.
  11. I don't convert F to C much, but for C to F you can do it in your head; double it, mentally take away 10% then add 32 for example: 100C: 100 doubles to 200. less 20 (which is 10%) is 180 plus 32 is 212
  12. This is the key point. Not all pursuit of technology is beneficial in the long run, but technology NOT pursued never produces benefits. So-- pursuit of success in fusion still seems like the right thing to do.
  13. I know absolutely nothing on this topic, but an article recently caught my eye that puts this in doubt: https://www.science.org/content/article/fusion-power-may-run-fuel-even-gets-started Last year, the Canadian tritium fueled an experiment at JET showing fusion research is approaching an important threshold: producing more energy than goes into the reactions. By getting to one-third of this breakeven point, JET offered reassurance that ITER, a similar reactor twice the size of JET under construction in France, will bust past breakeven when it begins deuterium and tritium (D-T) burns sometime next decade. “What we found matches predictions,” says Fernanda Rimini, JET’s plasma operations expert. But that achievement could be a Pyrrhic victory, fusion scientists are realizing. ITER is expected to consume most of the world’s tritium, leaving little for reactors that come after. Fusion advocates often boast that the fuel for their reactors will be cheap and plentiful. That is certainly true for deuterium: Roughly one in every 5000 hydrogen atoms in the oceans is deuterium, and it sells for about $13 per gram. But tritium, with a half-life of 12.3 years, exists naturally only in trace amounts in the upper atmosphere, the product of cosmic ray bombardment. Nuclear reactors also produce tiny amounts, but few harvest it.
  14. To the first question: a qualified yes: anyone who gets old will develop something, inasmuch as there has to be some step between healthy and dead. But-- luck and healthy habits can help. I can speak to this a little because at about the age of 35 I determined that aspirin did not seem to have any side effects for me, and I was a runner (which puts a lot of load on knees), so from the age of 35 to 75 I experimented with taking two full size aspiring with food every day of my life. The purpose being to prevent inflammation and all the many health issues that inflammation has been linked to. At 75 I cut back somewhat in order to avoid gout (aspirin tends to promote gout). The experiment is still continuing as I am only 76 and in good health and have never experienced inflammatory issues such as arthritis. My cholesterol has begin to rise and I am taking meds for that. The only disease of old age I have encountered is prostate cancer, which killed both my father and grandfather-- so I had that removed the instant the PSA started rising. That was over 9 years ago and has not returned. Luck and lifestyle do help-- but sooner or later something will bring things to an end.
  15. I forgot to add, above. that in reading the original challenge I overlooked the word "joined." With that word added I agree with Commander on the solution.
  16. The figure I suggested is both a quadrilateral and a polygon: Concave quadrilaterals In a concave quadrilateral, one interior angle is bigger than 180°, and one of the two diagonals lies outside the quadrilateral. polygon / (ˈpɒlɪˌɡɒn) / noun a closed plane figure bounded by three or more straight sides that meet in pairs in the same number of vertices, and do not intersect other than at these vertices.
  17. Did you really intend your challenge to apply to any class of quadrilateral? There are many types. For example, would one such as this be included?
  18. The practicality and efficiency of online teaching also depends on the subject matter. Subjects that involve a lot of one-on-one interaction with students are more difficult to effectively teach online. For example, good math instruction frequently requires to teacher to wander the classroom and observe individual students as they work problems and also to discuss individual problems with the students. That's difficult in an online environment. Computer programs for teaching math are used by many school systems, and suffer from the same issues.
  19. Agree! One of the arguments in favor of term limits was that it was supposed to help with this, since a person in their final term has no need to prepare for re-election. Unfortunately, a good friend of mine who is a California legislator has assured me that the problem with term limits (in this case two 6 year terms) is that "six years just isn't long enough to get to know your fellow legislators and get anything done." How many of us who have jobs outside politics have an employer willing to let us take 6 years to begin to be effective in our jobs?
  20. I see your point here. The reason I don't see it specifically as an economics and politics problem is because, even when the political and economical will is there to get things done, the deciding of what to do is still dependent on predicting what will work. Storage to be sure is important-- but we have water storage all over the west that is proving inadequate (Powell, Mead, San Luis Reservoir, Shasta and Oroville in California, Rye Patch in northern Nevada-- all getting rather dry). Thinking more about it, however, I do see that if voters wanted to spend the money and politicians listened, we could do many things, and be successful, even if some 'solutions' turned out to be less effective than others.
  21. I understand but don't agree. We may know what to do to address the issues in theory-- but properly predicting where there will be an excess of water and a shortage of water is a necessary element-- and to a large degree we don't know until after it has happened. Did anyone predict the floods in Kentucky specifically-- or just somewhere in the south-east US? That's what is necessary in order to apply solutions-- unless we spend huge amounts of money everywhere. The inability to specifically predict is what I allude to in talking about only knowing after the fact. There is much more to this beyond politics and economics.
  22. Evolution does not weed out all disorders because the causes of some disorders are evolving as well.
  23. The problem is with obvious engineering solutions is often that they are only obvious after the fact. Most of the planning depends on what the current experts believe is likely to happen, and the ability of experts to convince the public to pay for the work. It reminds me of the Fukushima disaster. I worked in the GE Nuclear Division. In planning the Nuclear Power Plant we knew their were earthquake and tsunami hazards. The Japanese scientists and experts predicted the magnitude of the need and the plant was built to handle it. Engineering solutions were planned and implemented-- then nature did more than predicted.
  24. Love it! I laugh because I come from a family of four boys, none of which have allergy issues. Our mother, who had only a high school education, had 'funny' ideas for her time about allergies. She encouraged all of us to play in the dirt as babies, and when one of us got a childhood disease she deliberately infected the other three. We are all well into old age and still seem to have pretty good immune systems.
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