A popular three-dimensional mesh generation scheme is to start with a quadrilateral mesh of the surface of a volume, and then attempt to fill the interior of the volume with hexahedra, so that the hexahedra touch the surface in exactly the given quadrilaterals[24]. Folklore has maintained that there are many quadrilateral meshes for which no such compatible hexahedral mesh exists. In this paper...

The aims ofthis study were (1) to apply the quadrilateral analysis to Saudi adult male and female patients with normal occlusion, (2) to compare the results to Saudi adult male and female with anterior openbite, and (3) to evaluate the correlation of the quadrilateral variables. The normal occlusion sample consisted of 60 lateral skull radiographs (30 male and 30 female) of Saudi adults with no...

We prove ten necessary and sufficient conditions for a convex quadrilateral to have perpendicular diagonals. One of these is a quite new eight point circle theorem and three of them are metric conditions concerning the nonoverlapping triangles formed by the diagonals. 1. A well known characterization An orthodiagonal quadrilateral is a convex quadrilateral with perpendicular diagonals. The most...

Mesh adaptation methods can improve the efficiency and accuracy of solutions to computational modeling problems. In many applications involving quadrilateral and hexahedral meshes, local modifications which maintain the original element type are desired. For triangle and tetrahedral meshes, effective refinement and coarsening methods that satisfy these criteria are available. Refinement methods...

In this work, a new method for mesh simpliication and surface reconstruction speciically designed for the needs of CAD/CAM engineering design and analysis is introduced. The method simpliies the original free-form face model by rst constructing restricted curvature deviation regions, generating a boundary conforming nite element quadrilateral mesh of the regions, and then tting a smooth surface...

In this paper we discuss the threat of malware targeted at extracting information about the relationships in a real-world social network as well as characteristic information about the individuals in the network, which we dub Stealing Reality. We present Stealing Reality (SR), explain why it differs from traditional types of network attacks, and discuss why its impact is significantly more dang...

This paper starts with developing kinematic and dynamic model of a snake shape robot in serpentine locomotion and finishes with actual experimentation. At the beginning the symmetrical and unsymmetrical serpenoid curves are introduced. Kinematics and dynamics of a snake robot on flat and inclined surfaces are obtained for a general n-link robot. SimMechanics toolbox of MATLAB software is employ...