Approximation algorithms for guarding holey polygons
نویسندگان
چکیده
منابع مشابه
Constant Approximation Algorithms for Guarding Simple Polygons using Vertex Guards
The art gallery problem enquires about the least number of guards sufficient to ensure that an art gallery, represented by a polygon P , is fully guarded. Most standard versions of this problem are known to be NP-hard. In 1987, Ghosh provided a deterministic O(log n)approximation algorithm for the case of vertex guards and edge guards in simple polygons. In the same paper, Ghosh also conjecture...
متن کاملApproximation algorithms for terrain guarding
We present approximation algorithms and heuristics for several variations of terrain guarding problems, where we need to guard a terrain in its entirety by a minimum number of guards. Terrain guarding has applications in telecommunications, namely in the setting up of antenna networks for wireless communication. Our approximation algorithms transform the terrain guarding instance into a MINIMUM...
متن کاملFast Vertex Guarding for Polygons
For a polygon P with n vertices, the vertex guarding problem asks for the minimum subset G of P ’s vertices such that every point in P is seen by at least one point in G. This problem is NP-complete and APX-hard. The first approximation algorithm (Ghosh, 1987) involves decomposing P into O ( n ) cells that are equivalence classes for visibility from the vertices of P . This discretized problem ...
متن کاملGuarding Fat Polygons and Triangulating Guarded Polygons
In this paper we study three related problems: (i) Given a fat polygon P , we show how to find a set G of points in P such that every point on the boundary of P sees at least one point of G. The set G is said to guard the boundary of P and its cardinality depends on the shape parameters of P . Fat polygons are often used to model more realistic inputs. (ii) Given k points that guard the boundar...
متن کاملOn k-Guarding Polygons
We describe a polynomial time O(k log log OPTk(P ))approximation algorithm for the k-guarding problem of finding a minimum number, OPTk(P ), of vertex guards of an n-vertex simple polygon P so that for every point p ∈ P , the number of guards that see p is at least the minimum of k and the number of vertices that see p. Our approach finds O ( k ε log log 1 ε ) size (k, ε)-nets for instances of ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Fundamental and Applied Sciences
سال: 2016
ISSN: 1112-9867
DOI: 10.4314/jfas.v8i3s.129