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Does God play dice?

Submitted by Aaron Goh on

I once came across a novel which contains the following (verbatim) :

Laplace had once prepared a paper for the Academie, claiming that it would be possible to predict the outcome of a game of dice if one had precise knowledge of every factor, such as the weight of the die, the exact way in which the hand moved, the strength of that hand, and the force of each throw.

Does a radially expanding cylinder bend?

Submitted by Amit Acharya on

 The Koiter-Sanders-Budiansky bending strain measure and a nonlinear generalization

 We know from strength of materials that non-uniform stretching of fibers along the cross section of a beam produces bending moments. But does this situation necessarily correspond to a 'bending' deformation? For that matter, what do we exactly mean kinematically when we talk about a bending deformation?

Molecular Dynamics - Whats going wrong?

Submitted by Aneet on

I have been writing a MATLAB code to reproduce the results of Verlets paper - Computer "experiments" on classical fluids, 1967.

Here is how I go about it:

 

- I initialize all the velocities (uniform distribution about [-1, 1])

- Initialize all positions  (NOT random allocations).

- I use Verlet's algorithm to update the positions.

 

Review of a few "Unified" Viscoplasticity Models (Motivated by solder deformation)

Submitted by yoursdhruly on

I had prepared this document for a class project, the level is introductory and the selection of models is motivated by solder deformation, but I hope it is of some help. I have examined four models, proposed by Hart, Anand, Krempl and Busso. The document has 16 pages.

Thanks,

Dhruv

PS: This is a wonderful website!!! 

Derivatives of the invariants of a tensor

Submitted by Biswajit Banerjee on

When you first start learning finite deformation plasticity, you will run into a plastic flow rate that can be derived from a flow potential such that 

(1)

whereis the Cauchy stress.  For an isotropic material with scalar internal variables, the plastic
flow potential can be assumed to have the form 

Multiple interacting three-dimensional flaws in electromagnetothermoelastic coupled multiphase composites by extended hypersing

Submitted by BoJing Zhu on

This work presents extended hypersingular integral equation (E-HIE) method to analyze the multiple interacting three-dimensional mixed-mode flaws problem in electromagnetothermoelastic coupled multiphase composites (EMTE-CMCs) under extended electro-magneto-thermo-elastic coupled loads through intricate theoretical analysis and numerical simulations.

Question: calculate normal to a parabola

Submitted by Anonymous (not verified) on

 

Hello:

I need advice on how to calculate the coordinates of a vector normal to a parabola section. The parabola is defined by 3 points on a plane: (x1,y1), (x2,y2), (x3,y3). I need to calculate the coordinates of the end point of the normal vector with the starting point (x2,y2) and a precribed magnitude A.

Any help would be greatly appreciated.

Thank you.

David.