old memories/physics
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t distribution and GSL random number generatorold memories/physics 2007. 7. 2. 22:57
t distribution with large degrees of freedom is the same as Normal (Gaussian) distribution with mean 0 and standard devitation 1 approximately.normal[x_] := PDF[NormalDistribution[0, 1], x]t[x_, nu_] := PDF[StudentTDistribution[nu]], x]Plot[{normal[x], t[x, 3], t[x, 6], t[x, 20]}, {x, -6, 6}, PlotStyle -> {Black, Gray, Blue, Red}]Five real random numbers x0 from the Gaussian distribution (0,1): ..
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Confidence Interval and Prediction Intervalold memories/physics 2007. 6. 20. 06:35
Confidence Interval (CI) describes the uncertainty in $\bar Y$ as an estimate of $\mu$, where $\bar Y$ is the sample mean and $\mu$ the population(true) mean 95% CI means that the true mean value will be inside this interval with 95% probabilitySuppose repeated samples of Y_i are taken of the same size and at the same fixed values of X as were used to determine the fitted line above. Then of all..
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PhD thesisold memories/physics 2006. 11. 30. 02:02
Writing the PhD thesis is so time-consuming work. Yes, definitely, it is too hard work for me. It is significantly different from master thesis. At that time, I had no idea about what I was writing and also it was written on Korean. During a whole day, just sit and type something. However, the next day, the almost everything, which was done the day before, must be modified or be deleted. Sometim..
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Toleranceold memories/physics 2006. 11. 8. 00:35
How do I make something exactly? This is a very difficult question. Before studying experimental physics, I have never thought about a tolerance. But, after studying, I realized it is so important to make a sort of decision. In the CAD world, everything is perfect except a few stupid mistakes, which are usually done by myself. In the Geant4, I also have to decide the tolerance, which is called c..