Title
Distance K-Sectors Exist
Abstract
The bisector of two nonempty sets P and Q in R(d) is the set of all points with equal distance to P and to Q. A distance k-sector of P and Q, where k >= 2 is an integer, is a (k - 1)-tuple (C(1),C(2), ... , C(k-1)) such that C(i) is the bisector of C(i-1) and C(i+1) for every i = 1, 2, ... , k - 1, where C(0) = P and C(k) = Q. This notion, for the case where P and Q are points in R(2), was introduced by Asano, MatouSek, and Tokuyama, motivated by a question of Murata in VLSI design. They established the existence and uniqueness of the distance 3-sector in this special case. We prove the existence of a distance k-sector for all k and for every two disjoint, nonempty, closed sets P and Q in Euclidean spaces of any ( nite) dimension (uniqueness remains open), or more generally, in proper geodesic spaces. The core of the proof is a new notion of k-gradation for P and Q, whose existence (even in an arbitrary metric space) is proved using the Knaster-Tarski xed point theorem, by a method introduced by Reem and Reich for a slightly di erent purpose.
Year
DOI
Venue
2010
10.1145/1810959.1810996
PROCEEDINGS OF THE TWENTY-SIXTH ANNUAL SYMPOSIUM ON COMPUTATIONAL GEOMETRY (SCG'10)
Keywords
DocType
Volume
distance k-sectors, Knaster-Tarski xed point theorem
Conference
abs/0912.4
Issue
Citations 
PageRank 
9
1
0.37
References 
Authors
4
5
Name
Order
Citations
PageRank
Keiko Imai18316.53
Akitoshi Kawamura210215.84
Jirí Matousek376376.77
Daniel Reem4779.11
Takeshi Tokuyama51179417.31