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Everything posted by OldChemE

  1. 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.
  2. Certainly there are creators and those created by them, but the physical evidence seems to show that the religious have the identities reversed.
  3. 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.
  4. 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
  5. 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.
  6. 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.
  7. 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.
  8. 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.
  9. 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.
  10. 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?
  11. 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.
  12. 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?
  13. 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.
  14. 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.
  15. Evolution does not weed out all disorders because the causes of some disorders are evolving as well.
  16. 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.
  17. 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.
  18. +1 I'm not convinced that conquest and expansion are always factors (the last paragraph of your post), but the geometry view (above) seems to me to be spot on. While it is somewhat removed form the morality question originally posed, I.m intrigued by the similarity to the origins of the US-- which started as a loose confederacy (more horizontal) but voluntarily switched to a more vertical arrangement as governance got more complex.
  19. I think horizontal vs vertical morality is also a function of scale. To Peterkin's point, the vertical component is, I believe, reflective of such large groups of people that they cannot all know the other members of the group well, so that they resort to judgements, rules, and such, while in smaller groups of people, such as mentioned by Peterkin, a situation more akin to horizontal morality prevails. I'm reminded of my college days where a small group of students (including myself) worked together on our studies. I am firmly in the camp that believes horizontal morality is preferable, but think there may be some critical point where our inability to personally know everyone leads to vertical morality.
  20. Two events at the same location could have different combinations of pressure temperature and volume, but have the same total energy. Energy alone is not sufficient to uniquely define an event. For example, an adiabatic process would go through many different states without exchanging energy with the environment.
  21. That's an interesting idea. If we are trying to identify the "properties of an event" it seems to me we are heading toward identifying all the characteristics that make the event unique, which is somewhat beyond dimensions. It brings to mind thermodynamics where we can define an event in terms of equations of state. This introduces other variables such as pressure, temperature, volume, mass, etc. I think I'm drifting away from your initial intent and will have to think some more about it.
  22. So-- I've read it all. and I do see some interesting points. However, I think the reason for a lot of bad feedback is that you are attempting to cover so much with so few words and lots of symbols. Just as an example, the sentence "Society (should/would/could) Service (a/the/those........" puts together many permutations of potential meaning all crammed into a singe sentence. For you this makes sense as a way to say much in little space-- for me it becomes a huge chore to separate the potential meanings, and even when the potential meanings are separate I can't be sure if they are the ones you meant to convey. Similarly, when you use two words with an equal sign in between "Individual perspective = reference" you are saying something that is obvious to you because you know the context in which you are making the statement. However, that context is in your mind but not in the written word. If you want others to understand you need to explain the context. In simple terms, if you want others to understand what you have to say you have to take the time to write whole sentences and explain things more. Try breaking the thing down into many parts a taking on only one part at a time.
  23. I don't know how to do the potassium chloride part, but if you are thinking of doing this do not go for a standard clock mechanism. Instead, look up "Anniversary Clock." An anniversary clock is a delicately balanced mechanism inside a glass housing that uses metal balls that rotate around a thin vertical flexible shaft. They rotate in one direction until the twist of the shaft stops them, then rotate in the opposite direction, etc, etc. The very tiny energy loss from the back and forth rotation is made up by the battery. With an ordinary "C" battery the anniversary clock I have has been keeping correct time for several years now without a battery change. With a better battery system you might achieve the "perpetual" goal.
  24. Yes-- both parties in America are getting down to that level. Whether or not it will continue will depend on voters (which includes my wife and myself). The really disgusting part is that all my life I have registered to vote as a Republican, because I prefer lower taxes, less centralized government, and a closer adherence to the US Constitution (which of course means all should be able to vote). Nothing that is going on now seems to align with my political preferences.
  25. Math is a generic word for many different uses for numbers; arithmetic, algebra, geometry, calculus and others. Having spent years as an engineer using different types of math, and also some years teaching math, I think the best way to look at math is that it is a set of tools. Just as a carpenter has tools (hammers, saws, etc) and a mechanic has tools, and a person who makes quilts has tools, so also there are many jobs and hobbies where you need tools using numbers to be successful. Which number tools you need depends on the job or hobby. In some jobs, counting (one, two..) is about all you need, in some others, the tool is extremely difficult math. So-- don't think of math as one thing just for irrational people (or some other set), but rather as a set of tools. Whether or not you need those tools, and which of the math tools it might be, depends on what you want to do.
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