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151,277
Efficient approximation algorithms for the achromatic number
, 2006
"... The achromatic number problem is, given a graph G = (V, E), to find the greatest number of colors, Ψ(G), in a coloring of the vertices of G such that adjacent vertices get distinct colors and for every pair of colors some vertex of the first color and some vertex of the second color are adjacent. Th ..."
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Cited by 3 (0 self)
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. This problem is NPcomplete even for trees. We obtain the following new results using combinatorial approaches to the problem. (1) A polynomial time O(V  3/8)approximation algorithm for the problem on graphs with girth at least six. (2) A polynomial time 2approximation algorithm for the problem on trees
An Efficient Approximation Algorithm for MaxCut
, 2013
"... Significant research effort has been devoted in the study of approximation algorithms for NPhard problems. Approximation algorithm for MaxCut problem with performance guarantee of 0.87856 is long known. In this work we study balanced MaxCut problem. We give a balancing factor β for given α such t ..."
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Significant research effort has been devoted in the study of approximation algorithms for NPhard problems. Approximation algorithm for MaxCut problem with performance guarantee of 0.87856 is long known. In this work we study balanced MaxCut problem. We give a balancing factor β for given α
An Efficient Approximation Algorithm for Combinatorial Auctions
"... We present a mathematical programming approximation approach to the winner determination problem for multiround combinatorial auctions. The winner determination problem is a set packing problem, and hence NPcomplete. Most methods developed recently rely on exhaustive search based methods which are ..."
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are exponential in worst case time complexity. We develop a two phase method where the first phase is a primaldual type approximation algorithm that rapidly computes an initial feasible solution and the second phase is a refinement procedure that uses the dual of the LP relaxation of the winner determination
Efficient Approximation Algorithms for Scheduling Unrelated Parallel Machines
, 2003
"... Scheduling n independent jobs on m Unrelated Parallel Machines (SUM) is the problem of assigning n jobs j = 1,.., n to m machines i = 1,..,m so that each job is processed without interruption on one of the machines, and at any time, every machine processes at most one job. The objective is to mini ..."
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is to minimize the makespan of the schedule. SUM is an NPhard problem even when the number of machines is defined to be m = 2. In this work, efficient approximation algorithms for SUM, when the number of machines is an arbitrary constant, are presented. The results hold for SUM and several extensions of SUM
An Efficient Approximation Algorithm for the Survivable Network Design Problem
 IN PROCEEDINGS OF THE THIRD MPS CONFERENCE ON INTEGER PROGRAMMING AND COMBINATORIAL OPTIMIZATION
, 1993
"... The survivable network design problem is to construct a minimumcost subgraph satisfying certain given edgeconnectivity requirements. The first polynomialtime approximation algorithm was given by Williamson et al. [20]. This paper gives an improved version that is more efficient. Consider a graph ..."
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Cited by 56 (6 self)
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The survivable network design problem is to construct a minimumcost subgraph satisfying certain given edgeconnectivity requirements. The first polynomialtime approximation algorithm was given by Williamson et al. [20]. This paper gives an improved version that is more efficient. Consider a graph
An Efficient Approximation Algorithm for the Fixed Routes Problem
, 1992
"... The Fixed Routes Problem is a variation of the Vehicle Routing Problem in which the routes that have to be constructed will be operated unchanged for an extended period of time while the customer demands within that period will vary. If, in a delivery scenario, a vehicle cannot satisfy the demand of ..."
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of a customer it musts return to the depot for replenishment before continuing its route. The fixed routes problem can be modeled as a vehicle routing problem with stochastic demands, which in turn can be solved with a stochastic programming model with recourse. An effective and efficient approximate
Efficient Approximation Algorithms for the Hamming Center Problem
, 1999
"... The Hamming center problem for a set S of k binary strings, each of length n, asks for a binary string of length n that minimizes the maximum Hamming distance between and any string in S. The decision version of this problem is known to be NPcomplete [6]. We provide several approximation algorit ..."
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Cited by 34 (2 self)
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algorithms for the Hamming center problem. Our main result is a randomized ( 4 3 + ")approximation algorithm running in polynomial time if the Hamming radius of S is at least superlogarithmic in k. Furthermore, we show how to nd in polynomial time a set B of O(log k) strings of length n
Efficient Approximation Algorithms for Scheduling Malleable Tasks
 In SPAA
, 1999
"... A malleable task is a computational unit which may be executed on any arbitrary number of processors, its execution time depending on the amount of resources allotted to it. According to the standard behavior of parallel applications, we assume that the malleable tasks are monotonic, i.e. that the e ..."
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Cited by 30 (1 self)
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. Then, the scheduling problem is solved by a dualapproximation which leads to a simple structure of two consecutive shelves.
An efficient approximate algorithm for winner determination in combinatorial auctions.
 In Proceedings of the Second ACM Conference on Electronic Commerce (EC00),
, 2000
"... ..."
Efficient approximation algorithms for the subsetsum problem
 in ICALP
, 1998
"... Abstract. We investigate the problem of finding two nonempty disjoint subsets of a set of n positive integers, with the objective that the sums of the numbers in the two subsets be as close as possible. In two versions of this problem, the quality of a solution is measured by the ratio and the diffe ..."
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Cited by 6 (0 self)
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that in the case where the value of a solution is the positive difference between the two partial sums, the problem is not 2 nkapproximable in polynomial time unless P=NP, for any constant k. In the positive direction, we give a polynomialtime algorithm that finds two subsets for which the difference of the two
Results 1  10
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151,277