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| Content Provider | ACM Digital Library |
|---|---|
| Author | Mitchell, Joseph S. B. Knauer, Christian Whittlesey, Kim Brönnimann, Hervé Arkin, Esther M. Erickson, Jeff Fekete, Sándor P. Alt, Helmut Lenchner, Jonathan |
| Abstract | We consider a class of geometric facility location problems in which the goal is to determine a set X of disks given by their centers $(t_{j})$ and radii $(r_{j})$ that cover a given set of demand points $Y∈R^{2}$ at the smallest possible cost. We consider cost functions of the form $Ε_{j}f(r_{j}),$ where $f(r)=r^{α}$ is the cost of transmission to radius r. Special cases arise for α=1 (sum of radii) and α=2 (total area); power consumption models in wireless network design often use an exponent α>2. Different scenarios arise according to possible restrictions on the transmission centers $t_{j},$ which may be constrained to belong to a given discrete set or to lie on a line, etc.We obtain several new results, including (a) exact and approximation algorithms for selecting transmission points $t_{j}$ on a given line in order to cover demand points $Y∈R^{2};$ (b) approximation algorithms (and an algebraic intractability result) for selecting an optimal line on which to place transmission points to cover Y; (c) a proof of NP-hardness for a discrete set of transmission points in $R^{2}$ and any fixed α>1; and (d) a polynomial-time approximation scheme for the problem of computing a minimum cost covering tour (MCCT), in which the total cost is a linear combination of the transmission cost for the set of disks and the length of a tour/path that connects the centers of the disks. |
| Starting Page | 449 |
| Ending Page | 458 |
| Page Count | 10 |
| File Format | |
| ISBN | 1595933409 |
| DOI | 10.1145/1137856.1137922 |
| Language | English |
| Publisher | Association for Computing Machinery (ACM) |
| Publisher Date | 2006-06-05 |
| Publisher Place | New York |
| Access Restriction | Subscribed |
| Subject Keyword | Covering problems Approximation Geometric optimization Tour problems Complexity |
| Content Type | Text |
| Resource Type | Article |
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