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Sensei

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Everything posted by Sensei

  1. Corrected version: [latex]f(x)=(1-sgn(abs(x-a_1)))*b_1 + (1-sgn(abs(x-a_2)))*b_2 + .... + (1-sgn(abs(x-a_n)))*b_n[/latex] a1....n are indexes. b1....n are values from sequence.
  2. [math]f(x)=sgn(abs(x-a_1))*b_1 + sgn(abs(x-a_2))*b_2 + .... + sgn(abs(x-a_n))*b_n[/math] a1....n are indexes. b1....n are values from sequence.
  3. Sequence 1,1,1,1,2,1,1,1,1 assuming the first one is x=0 could be received with [math]f(x)=2-sgn(abs(x-4))[/math] https://en.wikipedia.org/wiki/Sign_function x must be integer.
  4. I have isopropanol in HDPE bottle (bought in electronic shop).
  5. I am drawing sketches sometimes, but for myself. To first know what to remake in 3D application. I was using f.e. https://en.wikibooks.org/wiki/LaTeX/Mathematics https://en.wikibooks.org/wiki/LaTeX/Advanced_Mathematics
  6. I would not use them even in reply on this forum... It's even more hassle: you have to paint, take photo, transfer data from digital camera/smartphone, or scan (if you have scanner).. When in application it's easier. You can make error, and fix it, while on paper, you would have to start from scratch. Indeed. Use 3D application for such drawings. There is free Blender, there is NewTek's LightWave for $700 (student version is probably cheaper), Maxon's Cinema 4D, Autodesk's Maya, SideFX's Houdini, But these are more expensive.
  7. Do you have your own Cholesterol checking machine.. ? If yes, you could make a series of tests, how Cholesterol varies in day, taking test per hour, or couple hours, or how it changes after eating certain types of foods. Record in Excel/OpenOffice SpreadSheet time and reading from device. And time and thing that you ate. And present results here. I saw on the net graph how cholesterol level changes (Y axis), with quantity of consumed green tea (X axis). You could verify observation made in this article on yourself. https://www.healthaliciousness.com/blog/How-much-does-green-tea-lower-cholesterol.php Links at the bottom of article also try to answer your questions.
  8. Why unrealistic? Tritium is produced from Lithium.. Building fusion reactors will increase demand for Lithium even more. Neutrons are for free in currently existing nuclear plants.. So better to use them cleverly.
  9. Did you try PHP image generation? http://php.net/manual/en/image.examples-png.php JavaScript could download file from some URL, but instead of "image.png", there is PHP script instead, generating image. To have it with .png extension, there is needed to modify Apache and/or PHP configuration file, which file types are processed by PHP daemon. This way user does not even have to know script is run to make image. (not really required, one can have "generate.php" script output PNG, as browser recognize image by header, the first line in script in the above link)
  10. You don't need to do anything to make it happen. Free neutron decays to proton, electron and antineutrino, releasing 0.782 MeV per reaction with ~10 minutes half-life (~15 minutes mean-life). Mass-energy of neutron is 939.565 MeV/c^2 multiply it by 1e6 * 1.602176565*10^-19 to convert to Joules, divide by c^2, to have mass in kg: ~1.67492667626123E-027 1 g = 0.001 kg divide by 1.67492667626123E-027 gives 5.97e23 neutrons per gram Each one can release 0.782 MeV (782000 eV) per reaction. * 1.602e-19 (eV->J), * 5.97e23 neutrons = 74803398357 J Half on it will be taken by electrons, because antineutrino takes some energy. Alternatively you can subtract sum of mass of proton and electron from mass of neutron, in kg, multiply by c^2, and multiply by quantity of reactions.
  11. In Standard Model quarks have >4 MeV energy/mass, while electron/positron have 0.511 MeV energy/mass. How can it not being conflict.. ? When there is obviously missing mass/energy. For example, the lightest meson neutral pion has ~135 MeV energy/mass. After decay it can create free electron and free positron, and they're accelerated nearly to speed of light. Electron or positron don't decay to neutral pion, nor any other meson or baryon.
  12. If something extends lifetime from 70 years (usually wasted by ordinary people), to say 200 years, that's nearly 3 times more time to work on progressing even further. Using newly saved years to extend it the next few years.. But people have to work on it (physics,chemistry,biotechnology,medicine,rocket science,IT), in the first place.
  13. Lithium-7 can be made from Boron-10 after neutron capture. B-10 + n0 -> Li-7 + He-4 + 2.795 MeV Also it could be made by from Helium-4 after at least double neutron capture.
  14. That's what for he made thread about modifications of DNA, to fix damaged DNA.. To state it used to have during his yearly age.
  15. Did you read this? http://www.pcworld.com/article/2984716/laptop-computers/how-to-transform-your-laptop-into-a-gaming-powerhouse-with-an-external-graphics-card.html It makes pretty little sense to me. You have to buy PCI gfx card, have to buy PCIe adapter (like this one http://www.ebay.com/itm/Laptop-Expresscard-34-To-2-PCI-E-Slots-Adapter-Notebook-External-PCI-Express-/222173937192 ), cost more than my desktop motherboard, have to buy external power supply, have to buy external LED/LCD monitor with large enough size say 24"+.. Then why bother and not to buy the real desktop.. ? At home, I am using dual-LED 24"+ monitors, with Core i7 quad-core desktop.
  16. If you don't know, and don't want to know math, you really won't understand how these things work.. How to explain somebody who does not want to know math f.e. nonlinear electronic element? You probably don't even understand what it means.. Sensible book would show graph, with one parameter in X axis, and other parameter on Y axis. With equation allowing to get such function as on graph. I would suggest getting breadboard, https://en.wikipedia.org/wiki/Breadboard 760 pins unit cost me less than $2. With multimeter. The cheapest one $7. With range of various electronic elements to plug to breadboard. And battery. You should see on your own eyes what influence has plugging some element in circuit (in breadboard) on voltmeter, ammeter, wattmeter. How resistance changes with various resistors, how it changes with variable resistor while moving potentiometer. etc etc. Making LED light dimmer on breadboard would take less time than writing this post..
  17. There is one way to stop this: education, high quality education. For free. Making museum-Noe ark with dinosaurs and telling people story that they lived together, it's exactly reverse direction, stupefying people...
  18. Now I see what for you need infinite life: forever and ever entertainment..
  19. WHY would anyone start eating bacon??? It has way too much fat.. Maybe tiny (30% of single slice), cut into cubes, as a base for making scrambled eggs, instead of oil. In the past, education was only for elite. It's easily visible in statistics of illiterate persons graph with years/centuries on X axis. After late XIX it changed and public primary schools appeared for either poor and rich people. US data split to race http://nces.ed.gov/naal/lit_history.asp Now it is time for Universities for free..
  20. Capacitor in reality is gap in circuit, gap made of air, gas, vacuum, insulator. On the first electrode, electrons gather, and can't travel anymore, as there is gap, on the second electrode, electrons escape (electronical engineer would say "hole"). If too many electrons will gather and/or gap is small, electrons will fly through gap, and if it's made of insulator the most likely damage it, and capacitor won't work anymore correctly. You should read about breakdown voltage of insulators https://en.wikipedia.org/wiki/Breakdown_voltage For controlling brightness usually there is used variable resistor. https://en.wikipedia.org/wiki/Potentiometer Interesting element is also Varistor https://en.wikipedia.org/wiki/Varistor
  21. Okay. It's your vision. But what with your experimental knowledge in this area? Can you tell us, using your own words, how quantum physicists are checking what is charge of some stable or unstable particle... ?
  22. Resistor is limiting current I. I=U/R Say we have voltage U=5 V, and resistor has R=100 ohm, current I will be 5/100=0.05 Amperes. 50 mA (miliamps). https://en.wikipedia.org/wiki/Ampere Current multiplied by time, is Charge Q (unit Coulombs). Q=I*t https://en.wikipedia.org/wiki/Coulomb Q divided by elementary charge e=1.602*10^-19 C, is quantity of electrons. Q/e https://en.wikipedia.org/wiki/Elementary_charge If through circuit there is flowing 1 Ampere current, during 1 second period of time, it means there is 6.24*10^18 electrons flowing through it. Electron flowing through some element, especially resistor, is losing part of its energy, and it's dissipated, and usually observed as heat. Therefor large power resistors have heat sink or even fan. Sometimes it's useful, when we need to heat liquid, like it's in heating element, in coffee/tea making devices. https://en.wikipedia.org/wiki/Heating_element Which is basically resistor with very large resistance. 1000 Watts power heating element with voltage U=230 V in the mains, has to have resistance around 53 Ohm. I=4.35 A U=230 V P=4.35 A * 230 V = ~ 1000 W R=230 V/4.35 A = ~53 Ohm.
  23. For me it sounds you're trying to beat somebody who is already laying on the ground.... I met you in the gym, half century ago, in high school... I was the one you kicked when I was lying down.. Making compressing routine without making decompressing routine to check whether compressing routine is working fine, is nonsense, but you don't have to tell anybody...
  24. EdEarl, I am giving you even +100, you're thinking and going in the right direction, so far, people should find a way to optimize costs of making food, and at the same time, making food free of the charge. Literally free of charge. Nobody in this world should be dying hungry....
  25. By Gantry crane I meant device moving in one axis on the rails, in say axis "X", and with "header" moving in axis "Y", and up and down in axis "Z". Similar like 3D printer/plotter works. with some space between the rails. Distance between rails could be 5m, 10m, 20m. It doesn't matter. With some predefined "actions" made on vegetables. The important is how it's controlled and what "header" can do from control room. It's one time investment. But it needs pretty flat/neutralized ground. Somebody who finished engineering/robotics could make such device by himself/herself using 3 engines from scrapyard, for a fraction of price company would build it (as they need to have income and have to pay tax). Or one time neutralization of the ground.. To make it pretty flat, and possible to put rails in the ground, and further crane. Such cranes would allow 3D in vegetable plantation. Several layers of plants at various height above the ground with hydroponic techniques. Or even in towers 200m+ height. Each floor separate Gantry crane. With transparent the all walls and the all floors, so light from the Sun can enter inside.
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