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Coordinate system in Abaqus data file (*.dat)

Submitted by hycpla on
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Dear all,

I have a question which seems quite simple but has troubled me for quite some time: 

I have a composite tube modeled using layered solid elements C3D8, and I want to output radial, circumferential, and axial stress components averaged at preselected nodes (defined as a node set) in Abaqus data file (*.dat). Nevertheless, I would like to have those stress components expressed in a cylindrical coordinate system, rather than in local material coordinate system. I would appreciate it a lot if anyone knows whether it is possible to do so. Thanks.

Sampling data from large numerical simulations - part 2

Submitted by Biswajit Banerjee on

The new blog post discusses yet another application of the Linear Assignment Problem; in this case the use of the Hungarian algorithm for finding an optimal list of close data points to a set of point generated using Latin Hypercube sampling.  See http://www.parresianz.com//sampling/hungarian_algorithm/

-- Biswajit

RHEOLOGICAL MODELS

Submitted by Zhigang Suo on

The attached notes are written for a course on plasticity.  When I update the notes, I will post a link on my twitter account:  https://twitter.com/zhigangsuo.  

Rheology is the science of deformation.  This science poses a question for every material:  Given a history of stress, how do we predict the history of strain, or the other way around?

Expectation of higher order moment (Bayesian Stats)

Submitted by crg123 on

I am taking a course in Bayesian statistics, which is off my field. In the lecture notes, the instructor showed

E[X^2n] = (2n-1) σ^2n

and E[X^3 . Y] = E[Y^3 . X] = 3.ρ.σ^4  

where  σ = variance

E = expectation

X is a random variable.

ρ = cor(XY) = E[XY]/σ^2

Can anyone kindly explain how these equations were derived or atleast point me towards some text where I can understand this? Is this to do with the moment generating function?