Recent content by lanew

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    Reverse Engineering Derivations - How?

    This is for a graduate level Fracture Mechanics course. The title of the paper is: The effect of T -stress on crack-tip plastic zones under mixed-mode loading conditions.
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    Reverse Engineering Derivations - How?

    1. Homework Statement I have to reverse engineer a derivation in a paper and have no idea where to even start. The amount of terms are overwhelming and I can't imagine how the author even began. 2. Homework Equations The following equations are known...
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    MATLAB Problem With MATLAB RREF Function Returning Trivial Solution.

    I'm trying to solve a system of linearly dependent equations. I solved the first set no problem, but for some reason MATLAB is returning the trivial solution for the second one, can anyone explain why? Systems: eq1 = -29.7250 -3.0000 0 -3.0000 -0.3028 0 eq2 =...
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    Continuum Mechanics: Finding Plastic Strain

    1. Homework Statement [Broken] 2. Homework Equations \epsilon^{pl} = \epsilon - \epsilon^{el} \epsilon^{pl} = \epsilon - \frac{\bar{\sigma}}{E} r = \frac{\epsilon_w}{\epsilon_t} 3. The Attempt at a Solution I'm stuck trying to...
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    Comparing Orbitals of H and He+

    I'm not sure about calculating energy levels, but if you consider the amount of protons in a He+ atom versus a H atom, there are twice as many. This extra positive charge should cause a greater attraction inward on the proton. I think this change will also change the energy levels but can't help...
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    Continuum Mechanics Rotation Matrix Problem

    I think I figured it out using diagonalization. I combined the principal eigenvectors into a matrix \mathbf{R} and checked by multiplying it by the diagonal matrix of the principal values. \mathbf{A}=\mathbf{R}\mathbf{\lambda}\mathbf{R} \left[\begin{array}{ccc} 500 & 0 & 300 \\ 0 & 700 & 0...
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    Continuum Mechanics Rotation Matrix Problem

    1. Homework Statement The components of stress in the x_i reference Cartesian system at a point of interested have been determined to be: \left[\begin{array}{ccc} 500 & 0 & 300 \\ 0 & 700 & 0 \\ 300 & 0 & -100 \end{array}\right] \mathrm{MPa} Determine the principal values and directions of...
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    Rigid Body Rotation Application

    Sorry about that, here's a quick sketch:
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    Rigid Body Rotation Application

    1. Homework Statement I'm trying to include rigid body rotation in a problem I'm working on but can't seem to figure it out. Two shafts oriented vertically are connected by a thin cross member of length R. Holding one shaft stationary and applying a constant tangential load F to the other...
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    Statement of Purpose Without Research Experience?

    Hey All, I'm graduating next year with a BS in Mechanical Engineering and have begun applying to graduate programs in the same field. My problem is the Statement of Purpose (SoP). On top of everything else, you are supposed to include prior research experience. This is supposed to demonstrate...
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    Vertical Axis Wind Turbine Design Questions

    Certainly, here is a picture of the general idea: [Broken]. The swept area has been fixed at A=20\,m^2. I need to optimize the dimensions given this area. As I mentioned, I don't think my AoA...
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    Vertical Axis Wind Turbine Design Questions

    Hello All, I'm currently in the process of designing a numerical model for a vertical axis wind turbine, more specifically, a straight blade giromill. I'm currently having trouble because depending on the variables I choose, I can produce more power than available from the wind. My...
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    Continuum Mechanics: Eij and eif given coordinates and displacements

    1. Homework Statement" 2. Homework Equations E_{ij}=\frac{1}{2} \left( \frac{\partial{u_i}}{\partial{X_j}} \frac{\partial{u_j}}{\partial{X_i}} - \delta_{ij}\right)...