Recent content by Wxfsa

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    MATLAB Integrate y=x/(exp(x)-1) in MATLAB

    Quite a lot of effort goes into refining numerical methods. The optimization of your codes are without any doubt far inferior to what is already implemented by matlab. Also being able to learn the standard way to implement is a very crucial skill itself.
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    MATLAB Integrate y=x/(exp(x)-1) in MATLAB

    >integral(@(x)x./(exp(x)-1),0,1) This is how you integrate in Matlab. It is ridiculous to implement your own algorithm for anything other than educational purposes.
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    Graduate 2D Maxwell complex coordinate stretching PML

    I am no expert but you can look into "2D absorbing boundary conditions." I got that part correct, right? You have a Z polarized E field, xy polarized H field traveling in xy plane? http://www.engr.uky.edu/~gedney/courses/ee624/notes/EE624_Notes6.pdf I have implemented this in 1D, you need to...
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    Graduate Solving y=e^{t-t^2/2}: Luck or Methodology?

    I actually solved this qustion after much work, however I do not like m solution. It would be great if someone could link me somewhere that derives error function laplace transforms
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    Graduate Solving y=e^{t-t^2/2}: Luck or Methodology?

    you don't have to answer the question if you don't want to
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    Understanding Non-Linearity in Barton's Criteria for Rock Mechanics

    Those symbols don't mean anything to me, so I do not know which one is the input. Even so, I can say that it is non linear because there is nothing in that expression for which there could be a linear relationship. It would be a good idea to actually understand what "linearity" means whether it...
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    Graduate Solving y=e^{t-t^2/2}: Luck or Methodology?

    yes
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    Graduate Solving y=e^{t-t^2/2}: Luck or Methodology?

    e^{kx} cannot be a solution but I decided to try e^{k(x)} which gave me a ricatti equation and after I substituted k=q\frac{p'}{p} I got the original equation edit: this is the solution c_1e^{\frac{-x^2}{4}+x}+c_2e^{\frac{-x^2}{4}+x} \int ^x e^{\frac{-s^2}{2}+2s}ds
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    Graduate Solving y=e^{t-t^2/2}: Luck or Methodology?

    I know y=e^{t-t^2/2} is a solution but how do I reach it? I tried substituting y=uv, making u' terms disappear then I noticed that the resulting u''=(__)u could be solved by a gaussian but this seems like luck to me
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    Graduate Why Does the Projection of a Jinc Result in a Sinc?

    http://math.stackexchange.com/questions/1221767/a-bessel-function-integral
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    Graduate Why Does the Projection of a Jinc Result in a Sinc?

    It basically boils down to: show that: $$\int_{-\infty}^{\infty} dy \frac{J_1 \left ( \pi\sqrt{x^2+y^2} \right )}{\sqrt{x^2+y^2}} = \frac{2 \sin{\pi x}}{\pi x} $$ My life story (somewhat irrelevant): A jinc function is besselj(1,pi*r)/( 2r ), a sinc is sin(pi*x) / (pi*x) I have noticed, while...
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    Undergrad Mechanical Water Waves: Understanding Behavior

    I want to understand how water waves behave. I do not need to be able to solve them (although i would like a derivation) because I tried hard to find it but I were not able to find any source on it (i probably didn't know the terms i should have been searching for) The type of stuff I want to...
    • Wxfsa
    • Thread
    • Mechanical Water Waves
    • Replies: 1
    • Forum: Mechanics
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    Fastest response, quickest settling time

    The solution manual says so.
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    Fastest response, quickest settling time

    How would I find best K value, apart from trial and error?
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    Fastest response, quickest settling time

    What is written in my original post is the closed loop transfer function.