In this paper we consider planar polygons with parallel opposite sides. This type of polygons can be regarded as discretizations of closed convex planar curves by taking tangent lines at samples with pairwise parallel tangents. For this class of polygons, we define discrete versions of the area evolute, central symmetry set, equidistants and area parallels and show that they behave quite simila...

this study investigate information and communication technology influence on opposite sex relationship. current survey is based on questionnaires data. selected census population is 395 of shiraz city youths (age 18-30) chose using lin table and cluster method with estimated error of 5%. the results of this investigation shows that relationship with opposite sex depends on several factors such ...