This paper provides a study of integer linear programming formulations for the diameter con-strained spanning tree problem (DMSTP) in the natural space of edge design variables. Afterpresenting a straightforward model based on the well known jump inequalities a new stronger familyof circular-jump inequalities is introduced. These inequalities are further generalized in two ways:...

Microfabrication and micropatterning techniques in tissue engineering offer great potential for creating and controlling microenvironments in which cell behavior can be observed. Here we present a novel approach to generate layered patterning of hepatocytes on micropatterned fibroblast feeder layers using microfabricated polydimethylsiloxane (PDMS) stencils. We fabricated PDMS stencils to patte...

Warm deep drawing of polypropylene, a semi-crystalline thermoplastic polymer, is studied using finite element analysis. In this process, circular polypropylene blank preheated to temperature much below its melting and drawn into the shape flat-bottom cylindrical cup punch-die combination, both initially at 25°C. The material model used for analysis considers effects varying strain rate during p...

The isogeometric methodology has been successfully implemented in one-step inverse analysis of sheet metal stamping processes. However, these models are not capable analyzing forming processes that require severe deformation and several stages. This paper presents a multi-step to enhance the precision predictions initial blank, strain distributions, drawability formed parts. deals with minimiza...

in this work, an inverse finite element formulation was modified for considering material anisotropy in obtaining blank shape and forming severity of deep drawn orthotropic parts. in this procedure, geometry of final part and thickness of initial blank sheet were known. after applying ideal forming formulations between material points of initial blank and final shape, an equation system was obt...