1

We introduce the concept of homotopic spanners in the plane with obstacles and show lower bounds on the number of edges that they require. We also provide a construction based on Θ-graphs for constructing homotopic spanners.

Constraints can be used to specify and maintain spatial relationships among objects in a geometric design. In the 3-D geometric design domain , the diversity of possible relationships among objects makes it diicult for the designer to specify useful or intended relationships in a productive and intuitive manner. We have built a constraint-based 3D geometric editor called DEVI that infers possib...

The linear response theory for current is investigated in a variational context. Expressions are derived for the Drude and superfluid weights for general variational wavefunctions. The expression for the Drude weight highlights the difficulty in its calculation since it depends on the exact energy eigenvalues which are usually not available in practice. While the Drude weight is not available i...

Collision detection between hard-sphere representations of molecules can be performed in interactive times on existing graphics hardware. This thesis presents a system that allows a user to interactively move a small drug molecule near a larger receptor molecule and have the system immediately inform the user when a collision between the two molecules has occurred. The system uses a 3-D grid da...

In this paper, the non-linear dynamic response of novel steel sandwich panel with hollow I-core subjected to blast loading was studied. Special emphasis is placed on the evaluation of midpoint displacements and energy dissipation of the models. Several parameters such as boundary conditions, strain rate, mesh dependency and asymmetrical loading are considered in this study. The material and geo...

In this paper, static response and buckling analysis of functionally graded saturated porous beam resting on Winkler elastic foundation is investigated. The beam is modeled using higher-order shear deformation theory in conjunction with Biot constitutive law which has not been surveyed so far. Three different patterns are considered for porosity distribution along the thickness of the beam: 1) ...

Drought is one of the major problems affecting crops production, including corn, in many parts of Iran. In order to detect drought tolerant grain corn hybrids, an experiment with twenty corn hybrids was conducted during 2006 in Qom Province, Iran, using a complete randomized block design with four replications, under optimal moisture and drought stress condition. Results showed diversity among ...

In order to identify drought tolerant chickpea genotypes, an experiment was conducted in the west of Iran, during 2007-2009 cropping seasons. Several selection indices were used to illustrate genotypic differences in response to drought stress. The results of combined analysis of variance showed that year, genotype, stress conditions and their interaction effects were highly significant. Correl...