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Professor Yonggang Huang from Northwestern University presented this
year's Nowinski Lecture at the University of Delaware on 12/5/2008, http://www.udel.edu/udaily/2009/nov/nowinskilecture112108.html.

Hi all!

In theories of failure (e.g von-Mises, Tresca, Max. principal stress etc), yield funcion,          f(sigma ij, Y) = 0 is plotted in principal stress space (sigma 1, sigma2 and sigma 3). Why shouldn't we express the same yield function, f(epsilon ij, epsilon Y) = 0 and plot in principal strain space?

Y = Yiled stress, sigma ij = stress ij, epsilon ij = strain ij. and espsilon Y = Yield strain = Y/E,   E = Young's modulus

Any thoughtful comments???

With regards,

- Ramdas

Nature recently favorably reviewed a new self-published book, based on a blog , by a "female physical sciences professor" in the US.  While the overarching theme is clearly about being a female in a male-dominated world, the writings on the blog (and in the book) are in many places general and provide lots of good advice and anecdotes about acadmic life.  The

Under the practical manufacturing process, metal parts will deform according the loads exerted on them. I did some practical measurement on the mentioned metal parts before and after the deformation.e.g.Heat treatment, the metal parts could be expanded or screwed.The postions I used to measure the dimension of the metal part could not be traced.Simply to use the difference of the widths at some specific positions, for example, has non-sense to indicate the deformation of the metal parts.On the other hand, I could use Catia to simulate some deformations of the metal parts.

I have a beam whose two ends are roller condition which means one end is zero moment and zero displacement and the other end is zero moment but can have the displacement only along the beam axis. Then the compression force is applied on this end along the beam axis.

hi am doing my project on high speed machining of aluminium and steel. for chip propagation i want some procedure how to do crack/fracture analysis using ABAQUS. if anybody knew about this please send me information regarding steps involved in building crack propagation.if any practile examples or tutorials are available for this send me to my mail id. my mail id is sasivamsi [at] gmail.com. am using ABAQUS V6.6.

Hi, everyone,

I am new here. Now I am doing a research which is related to the Euler's buckling formula.  It is known that when the cylinder is thick enough, Euler's buckling formula is no longer valid. I want to know in which region of slenderness(aspect ratio) of a cylinder or column that the Euler's buckling formula is valid. Is there any analytical study or numerical results about it? Is there any suggestion or paper I can find?

 Thank you very much! 

The fractal crack model described here incorporates the essential

features of the fractal view of fracture, the basic concepts of

the LEFM model, the concepts contained within the

Barenblatt-Dugdale cohesive crack model and the quantized

(discrete or finite) fracture mechanics assumptions. The

well-known entities such as the stress intensity factor and the

Barenblatt cohesion modulus, which is a measure of material

toughness, have been re-defined to accommodate the fractal view of

fracture.