POINT VISIBILITY GRAPHS AND ${\mathcal O}$-CONVEX COVER

A visibility relation can be viewed as a graph: the uncountable graph of a visibility relationship between points in a polygon P is called the point visibility graph (PVG) of P. In this paper we explore the use of perfect graphs to characterize tractable subproblems of visibility problems. Our main result is a characterization of which polygons are guaranteed to have weakly triangulated PVGs, under a generalized notion of visibility called [Formula: see text]-visibility. Let [Formula: see text] denote a set of line orientations. A connected point set P is called [Formula: see text]-convex if the intersection of P with any line with orientation in [Formula: see text] is connected. Two points in a polygon are said to be [Formula: see text]-visible if there is an [Formula: see text]-convex path between them inside the polygon. Let [Formula: see text] denote the set of orientations perpendicular to orientations in [Formula: see text]. Let [Formula: see text] be the set of orientations θ such that a "reflex" local maximum in the boundary of P exists with respect to θ. Our characterization of which polygons have weakly-triangulated PVGs is based on restricting the cardinality and span of [Formula: see text]. This characterization allows us to exhibit a class of polygons admitting a polynomial algorithm for [Formula: see text]-convex cover.

اثر خصائص التنظيم الفضائي والبصري لابنية المتاحف في تشكيل انماط الزيارة

Museums add cultural and social values to their societies, by transferring knowledge to the visitors through their exhibits. Accordingly, movement/visibility relation is considered as a crucial aspect in explaining spatial manners of museums, and direct operator in the formation of visiting patterns. The relation between both faces of museum's spatial configuration (movement axes, and visibility network), represents phenomena that lacks adequate research endeavors, despite its importance in the formation of visiting experiment patterns. Accordingly, the study aims to explain this relation. Using the comparative analysis methodology between Iraqi and international museum buildings. The results show full coincidence of the most integrated movement axes with the most integrated visibility areas, in some cases. And partial coincidence in others. With special syntactic position for Gathering Spaces in Museums.

اثر خصائص التنظيم الفضائي والبصري لابنية المتاحف في تشكيل انماط الزيارة

Museums add cultural and social values to their societies, by transferring knowledge to the visitors through their exhibits. Accordingly, movement/visibility relation is considered as a crucial aspect in explaining spatial manners of museums, and direct operator in the formation of visiting patterns. The relation between both faces of museum's spatial configuration (movement axes, and visibility network), represents phenomena that lacks adequate research endeavors, despite its importance in the formation of visiting experiment patterns. Accordingly, the study aims to explain this relation. Using the comparative analysis methodology between Iraqi and international museum buildings. The results show full coincidence of the most integrated movement axes with the most integrated visibility areas, in some cases. And partial coincidence in others. With special syntactic position for Gathering Spaces in Museums.