Type
ArticleKAUST Department
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) DivisionComputer Science Program
Visual Computing Center (VCC)
Geometric Algorithms Group
Date
2011-11-20Online Publication Date
2011-11-20Print Publication Date
2011-04Permanent link to this record
http://hdl.handle.net/10754/561744
Metadata
Show full item recordAbstract
In this paper we study several instances of the aligned k-center problem where the goal is, given a set of points S in the plane and a parameter k ≥ 1, to find k disks with centers on a line ℓ such that their union covers S and the maximum radius of the disks is minimized. This problem is a constrained version of the well-known k-center problem in which the centers are constrained to lie in a particular region such as a segment, a line, or a polygon. We first consider the simplest version of the problem where the line ℓ is given in advance; we can solve this problem in time O(n log2 n). In the case where only the direction of ℓ is fixed, we give an O(n2 log 2 n)-time algorithm. When ℓ is an arbitrary line, we give a randomized algorithm with expected running time O(n4 log2 n). Then we present (1+ε)-approximation algorithms for these three problems. When we denote T(k, ε) = (k/ε2+(k/ε) log k) log(1/ε), these algorithms run in O(n log k + T(k, ε)) time, O(n log k + T(k, ε)/ε) time, and O(n log k + T(k, ε)/ε2) time, respectively. For k = O(n1/3/log n), we also give randomized algorithms with expected running times O(n + (k/ε2) log(1/ε)), O(n+(k/ε3) log(1/ε)), and O(n + (k/ε4) log(1/ε)), respectively. © 2011 World Scientific Publishing Company.Citation
BRASS, P., KNAUER, C., NA, H.-S., SHIN, C.-S., & VIGNERON, A. (2011). THE ALIGNED K-CENTER PROBLEM. International Journal of Computational Geometry & Applications, 21(02), 157–178. doi:10.1142/s0218195911003597Sponsors
Author for correspondence; Supported by Korean Research Foundation Grant (KRF-2007-531-D00018).Supported by National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2010-0016416), and the HUFS Research Fund.Publisher
World Scientific Pub Co Pte Ltae974a485f413a2113503eed53cd6c53
10.1142/S0218195911003597