Results 21 to 30 of about 83,874 (238)
Simple heuristics for unit disk graphs [PDF]
AbstractUnit disk graphs are intersection graphs of circles of unit radius in the plane. We present simple and provably good heuristics for a number of classical NP‐hard optimization problems on unit disk graphs. The problems considered include maximum independent set, minimum vertex cover, minimum coloring, and minimum dominating set.
S. S. Ravi+4 more
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Minimum Bisection Is NP-hard on Unit Disk Graphs [PDF]
17 pages, 6 ...
Díaz Cort, Josep, Mertzios, George B.
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compact routing in unit disk graphs
Let V ⊂ ℝ² be a set of n sites in the plane. The unit disk graph DG(V) of V is the graph with vertex set V where two sites v and w are adjacent if and only if their Euclidean distance is at most 1. We develop a compact routing scheme ℛ for DG(V). The routing scheme ℛ preprocesses DG(V) by assigning a label 𝓁(v) to every site v in V.
Mulzer, Wolfgang, Willert, Max
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Hierarchically specified unit disk graphs
AbstractWe characterize the complexity of a number of basic optimization problems for unit disk graphs specified hierarchically as in [2, 17, 19, 20]. Both PSPACE-hardness results and polynomial time approximations are presented for most of the problems considered.
Venkatesh Radhakrishnan+3 more
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Reverse Shortest Path Problem for Unit-Disk Graphs [PDF]
Given a set P of n points in the plane, the unit-disk graph Gr(P) with respect to a parameter r is an undirected graph whose vertex set is P such that an edge connects two points p, q \in P if the Euclidean distance between p and q is at most r (the weight of the edge is 1 in the unweighted case and is the distance between p and q in the weighted case).
Wang, Haitao, Zhao, Yiming
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Approximating Minimum Independent Dominating Sets in Wireless Networks [PDF]
We present the first polynomial-time approximation scheme (PTAS) for the Minimum Independent Dominating Set problem in graphs of polynomially bounded growth.
Hurink, J.L., Nieberg, T.
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Approximation Algorithms for Unit Disk Graphs [PDF]
We consider several graph theoretic problems on unit disk graphs (Maximum Independent Set, Minimum Vertex Cover, and Minimum (Connected) Dominating Set) relevant to mobile ad hoc networks. We propose two new notions: thickness and density. If the thickness of a unit disk graph is bounded, then the mentioned problems can be solved in polynomial time ...
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Efficient independent set approximation in unit disk graphs [PDF]
Abstract We consider the maximum (weight) independent set problem in unit disk graphs. The high complexity of the existing polynomial-time approximation schemes motivated the development of faster constant approximation algorithms. In this paper, we present a 2.16-approximation algorithm that runs in O ( n log 2 n ) time and a 2 ...
Gautam K. Das+2 more
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Bidimensionality and Geometric Graphs
In this paper we use several of the key ideas from Bidimensionality to give a new generic approach to design EPTASs and subexponential time parameterized algorithms for problems on classes of graphs which are not minor closed, but instead exhibit a ...
Fomin, Fedor V.+2 more
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On Geometric Spanners of Euclidean and Unit Disk Graphs [PDF]
We consider the problem of constructing bounded-degree planar geometric spanners of Euclidean and unit-disk graphs. It is well known that the Delaunay subgraph is a planar geometric spanner with stretch factor $C_{del\approx 2.42$; however, its degree may not be bounded.
Perkovic, Ljubomir, Kanj, Iyad A.
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