External visibility

On Rectangle Visibility Graphs. III. External Visibility and Complexity

Visibility of puncture sites after external osteotomy in rhinoplastic surgery.

BACKGROUND External lateral osteotomy performed through a small puncture incision in the skin has numerous advantages, but it has been criticized by its opponents who claim it may leave visible scars. OBJECTIVE To examine whether the external lateral osteotomy actually leaves visible scars. METHODS Eighty-one postoperative photographs of patients who had undergone the external lateral osteo...

Cone Visibility Decomposition Cone Visibility Decomposition Cone Visibility Decomposition Cone Visibility Decomposition Cone Visibility Decomposition Cone Visibility Decomposition

(a) (b) Figure 8: The nal set of directions from that covers G S in thick gray lines. Two views are provided with (a) presents the regular view of Figures 5 to 7 and (b) shows the entire Gauss map. See also Figure 1. (a) (b) Figure 6: The boundary and central silhouettes of G S in thick dark gray lines is projected onto the plane z = 1 in thick light gray lines, in (a). In (b), The convex hull ...

On the number of internal and external visibility edges of polygons

In this paper we prove that for any simple polygon P with n vertices, the sum of the number of strictly internal edges and the number of strictly external visibility edges of P is at least b 3n−1 2 c − 4. The internal visibility graph of a simple polygon P is the graph with vertex set equal to the vertex set of P , in which two vertices are adjacent if the line segment connecting them does not ...

Tree-visibility Orders Tree-visibility Orders

In this paper we introduce a new class of partially ordered sets, called tree-visibility orders, extending the class of interval orders in a fashion similar to the extension of interval graphs to chordal graphs. This class contains interval orders, duals of generalized interval orders and height one orders. We give a characterization of tree-visibility orders by an innnite family of minimal for...