The analysis of the electromagnetic scattering from perfectly electrically conducting (PEC) objects with edges and corners performed by means of surface integral equation formulations has drawbacks due to the interior resonances and divergence of the fields on geometrical singularities. The aim of this paper is to show a fast converging method for the analysis of the scattering from PEC polygon...

This work explores an alternative approach to the problem of collision detection using images instead of geometry to represent complex polygonal environments and buildings derived from laser scan data, used in an interactive navigation scenario. In a preprocessing step, models that are not point clouds, are sampled to create representative point clouds. Our algorithm then creates several 2.5+D ...

The electromagnetic superabsorber that has larger absorption cross section than its real size may be a novel photothermal device with improved solar energy conversion rates. Based on a transformation optical approach, the material parameters for a two-dimensional (2D) metamaterial-assisted electromagnetic superabsorber with arbitrary geometries are derived and validated by numerical simulation....

In the present work, the origin of antiprotons observed in cosmic rays (above the atmosphere) is analyzed in details. We have considered the origin of the primaries, (which their interactions with the interstellar medium is one of the most important sources of antiprotons) is a supernova type II then used a diffusion model for their propagation. We have used the latest parameterization for anti...

a celebrated result of i. schur asserts that the derived subgroup of a group is finite provided the group modulo its center is finite, a result that has been the source of many investigations within the theory of groups. in this paper we exhibit a similar result to schur's theorem for vector spaces, acted upon by certain groups. the proof of this analogous result depends on the characteristic o...