New fabrication technologies have significantly decreased the cost of fabrication of shapes with highly complex geometric structure. One important application of complex fine-scale geometric structures is to create variable effective elastic material prope ...
The first example of a closed orientable hyperbolic 3-manifold was constructed by F. Lobell in 1931 from eight copies of the right-angled 14-hedron. We consider the family of hyperbolic polyhedra which generalize the Lambert cube and the Lobell polyhedron. ...
A geometric method of lattice reduction based on cycles of directional and hyperplanar shears is presented. The deviation from cubicity at each step of the reduction is evaluated by a parameter called 'basis rhombicity' which is the sum of the absolute val ...
We demonstrate the self-formation of hexagonal nanotemplates on GaAs (111)B substrates patterned with arrays of inverted tetrahedral pyramids during metal-organic vapor phase epitaxy and its role in producing high-symmetry, site-controlled quantum dots (QD ...
This paper presents the rotor design optimization for a reaction sphere (RS) actuator. The RS is a permanent-magnet synchronous spherical actuator whose rotor is magnetically levitated and can be accelerated about any desired axis. The RS is composed of an ...
Institute of Electrical and Electronics Engineers2014
This paper presents a hybrid FEM-analytical model for the magnetic flux density, the force and torque of a Reaction Sphere (RS) actuator for satellite attitude control. The RS is a permanent magnet synchronous spherical actuator whose rotor is magnetically ...
The objective of this paper is to present two types of results on Minkowski sums of convex polytopes. The first is about a special class of polytopes we call perfectly centered and the combinatorial properties of the Minkowski sum with their own dual. In p ...