research

I’m working on optical method for displacement measurement. and this is interesting to know more about application and development of these methods like ESPI , SHEAROGRAPHY anf HOLOGRAPHY . for example i face with a company that climb their product can give displacement and so strain field in many material and many geometry even in 3-D shapes!!

http://www.dantecdynamics.com/Default.aspx?ID=1029 

In this recently published paper on Nanotechnology, we studied the in-surface buckling mechanics of one dimensional nanomaterials on elastomeric substrates.  Simple analytical solutions are obtained for buckling wavelength and amplitude, which can be easily applied to the in-surface buckling of different nanomaterials, such as nanowires and nanotubes.  It is shown that in-surface buckling of nanomaterials has lower energy than out-of-surface buckling, which explains the experimental observance o

In a previous work, substrate-modulated morphology of graphene was analyzed using a numerical Monte Carlo method. Here we present an analytical approach that explicitly relates the van der Waals interaction energy to the surface corrugation and the interfacial properties. Moreover, the effect of mismatch strain is considered, which predicts a strain-induced instability under a compressive strain and reduced corrugation under a tensile strain.

I have a question regarding Gurson model. If we have a cube with initial length of unit and initial porosity of 20 percent and compress it hydrostatically in order to have a huge volume change of cube, the void growth equation in Gurson model takes a negative rate and reduces the void volume fraction to zero first and further compressing leads to no further void volume fraction change (remains zero) and no more plastic straining. Now let's load the model in tensile hydrostatic state up to a stress free configuration; the void volume fraction of the model remains zero.