We give a characterization of translation ovoids of flock generalized quadrangles. Then we prove that, if q = 2e , each elation generalized quadrangle defined by a flock has a large class of translation ovoids which arise from semifields of dimension two over their left nucleus. Finally, we give some examples when q is odd. © 2003 Elsevier Ltd. All rights reserved. MSC (2000): Primary 51E12; Se...

There are a number of important substructures associated with sets of points of antiregular quadrangles. Inspired by a construction of P. Wild, we associate with any four distinct collinear points p, q, r and s of an antiregular quadrangle an incidence structure which is the union of the two biaffine planes associated with {p, r} and {q, s}. We investigate when this incidence structure is a sem...

An octagon quadrangle is the graph consisting of an 8-cycle (x1, ..., x8) with two additional chords: the edges {x1, x4} and {x5, x8}. An octagon quadrangle system of order v and index λ [OQS] is a pair (X,B), where X is a finite set of v vertices and B is a collection of edge disjoint octagon quadrangles (called blocks) which partition the edge set of λKv defined on X. A 4-kite is the graph ha...

This paper presents a probability method for detecting people in a static image. We simplify people as a torso and four limbs. The torso is fitted by a quadrangle, and each limb is fitted by one or two quadrangles depending on its pose. In order to find people, we should try to find a combination of quadrangles that must satisfy some geometric and topological constrains. Firstly, we try to dete...

We study random constructions in incidence structures, and illustrate our techniques by means of a well-studied example from finite geometry. A maximal partial ovoid of a generalized quadrangle is a maximal set of points no two of which are collinear. The problem of determining the smallest size of a maximal partial ovoid in quadrangles has been extensively studied in the literature. In general...

A dodecagon quadrangle is the graph consisting of two cycles: a 12cycle (x1, x2, ..., x12) and a 4-cycle (x1, x4, x7, x10). A dodecagon quadrangle system [DQS] of order v and index λ [DQSλ] is a pair Σ = (X,B), where X is a finite set of v vertices and B is a collection of edge disjoint dodecagon quadrangles (called blocks) which partitions the edge set of λKv, the complete multigraph with vert...

El presente estudio establece los contrastes entre las condiciones de vivienda digna y adecuada del departamento Norte Santander, Colombia, desde el enfoque desarrollo a escala humana (DEH). Se usa una metodología cualitativa para la construcción matriz necesidades existenciales axiológicas, en su elaboración se realizó un análisis política pública plan departamental. Los resultados proponen qu...

The trace fossil assemblages from the Unit 2 of Deh-Sufiyan Formation are described for the first time from The Central Alborz Range of northern Iran,  improving the record of the assemblages in the Cambrian of the Middle East. Twenty-one ichnogenera have been identified in the Deh-Sufiyan Formation, namely Arenicolites, Bergaueria, Chondrites, Circulichnus, Cruziana, Diplichnites, Didymaulichnu...