manoeuvre, is one of the principles of war in most of the world’s armies. mobility and manoeuvre of the operational and support forces in the battle fields occur in bed of natural and cultural geographic factors, i.e, avenue approach and frontier transportation networks. so for this reason analyzing this geographical factors in skills such as line identification in tactical and operational leve...

We investigate how a straight skeleton can be used to approximate a motorcycle graph. We explain how to construct a planar straight-line graph G such that the straight skeleton of G reveals the motorcycle graph of M , for every given finite set M of motorcycles. An application of our construction is a proof of the Pcompleteness of the construction problem of straight skeletons of planar straigh...

 ABSTRACT Study design: A cross-sectional non-experimental study. Objectives: To collectively detect the reliability and feasibility of the five types of clinical tests that have been used to measure endurance of the trunk muscles in subjects with and without low back pain (LBP) and identifY the sensitivity of each test to predict the probability of the occurrence ofLBP. Background: Testing spi...

the key to successful long-term peritoneal dialysis (pd) is permanent and safe access to peritoneal cavity. the two most commonly used tenckoff catheters for pd are the straight and coiled catheters. the present study was undertaken to assess the catheter survival, catheter associated infections, and all cause mortality and to compare the straight with coiled catheters in pd. during april 1997-...

We introduce additively-weighted straight skeletons as a new generalization of straight skeletons. An additively-weighted straight skeleton is the result of a wavefront-propagation process where, unlike in previous variants of straight skeletons, wavefront edges do not necessarily start to move at the begin of the propagation process but at later points in time. We analyze the properties of add...

We characterize the self-parallel (mitered) offsets of a general nonconvex polytope Q in 3-space and give a canonical algorithm that constructs a straight skeleton for Q.

The straight skeleton of a polygon is the geometric graph obtained by tracing the vertices during a mitered offsetting process. It is known that the straight skeleton of a simple polygon is a tree, and one can naturally derive directions on the edges of the tree from the propagation of the shrinking process. In this paper, we ask the reverse question: Given a tree with directed edges, can it be...