Results 1  10
of
1,424,892
Analysis of Approximation Algorithms for kSet Cover using . . .
"... We present new combinatorial approximation algorithms for kset cover. Previous approaches are based on extending the greedy algorithm by efficiently handling small sets. The new algorithms further extend them by utilizing the natural idea of computing large packings of elements into sets of large ..."
Abstract

Cited by 7 (3 self)
 Add to MetaCart
We present new combinatorial approximation algorithms for kset cover. Previous approaches are based on extending the greedy algorithm by efficiently handling small sets. The new algorithms further extend them by utilizing the natural idea of computing large packings of elements into sets of large
Approximation of kSet Cover by SemiLocal Optimization
 In Proc. 29th STOC
, 1997
"... We define a powerful new approximation technique called semilocal optimization. It provides very natural heuristics that are distinctly more powerful than those based on local optimization. With an appropriate metric, semilocal optimization can still be viewed as a local optimization, but it has t ..."
Abstract

Cited by 40 (0 self)
 Add to MetaCart
the advantage of making global changes to an approximate solution. Semilocal optimization generalizes recent heuristics of Halldorsson for 3Set Cover, Color Saving, and kSet Cover. Greatly improved performance ratios of 4/3 for 3Set Cover and 6/5 for Color Saving in graphs without independent sets of size 4
Approximating kSet Cover and Complementary Graph Coloring
"... We consider instances of the Set Cover problem where each set is of small size. For collections of sets of size at most three, we obtain improved performance ratios of 1.4 + ffl, for any constant ffl? 0. Similar improvements hold also for collections of larger sets. A corollary of this result is an ..."
Abstract

Cited by 29 (0 self)
 Add to MetaCart
We consider instances of the Set Cover problem where each set is of small size. For collections of sets of size at most three, we obtain improved performance ratios of 1.4 + ffl, for any constant ffl? 0. Similar improvements hold also for collections of larger sets. A corollary of this result
Approximating the unweighted kset cover problem: greedy meets local search
 In Proceedings of the 4th International Workshop on Approximation and Online Algorithms (WAOA ’06), LNCS 4368
, 2006
"... Abstract. In the unweighted setcover problem we are given a set of elements E = {e1, e2,..., en} and a collection F of subsets of E. The problem is to compute a subcollection SOL ⊆F such that � Sj ∈SOL Sj = E and its size SOL  is minimized. When S  ≤ k for all S ∈ F we obtain the unweighted k ..."
Abstract

Cited by 9 (1 self)
 Add to MetaCart
kset cover problem. It is well known that the greedy algorithm is an Hkapproximation algorithm for the unweighted kset cover, where Hk = �k 1 is the kth harmonic number, and that this i=1 i bound on the approximation ratio of the greedy algorithm, is tight for all constant values of k. Since
Parameterized algorithms for the max kset cover and related satisfiability problems
, 2013
"... ..."
A Threshold of ln n for Approximating Set Cover
 JOURNAL OF THE ACM
, 1998
"... Given a collection F of subsets of S = f1; : : : ; ng, set cover is the problem of selecting as few as possible subsets from F such that their union covers S, and max kcover is the problem of selecting k subsets from F such that their union has maximum cardinality. Both these problems are NPhar ..."
Abstract

Cited by 778 (5 self)
 Add to MetaCart
Given a collection F of subsets of S = f1; : : : ; ng, set cover is the problem of selecting as few as possible subsets from F such that their union covers S, and max kcover is the problem of selecting k subsets from F such that their union has maximum cardinality. Both these problems are NP
Some optimal inapproximability results
, 2002
"... We prove optimal, up to an arbitrary ffl? 0, inapproximability results for MaxEkSat for k * 3, maximizing the number of satisfied linear equations in an overdetermined system of linear equations modulo a prime p and Set Splitting. As a consequence of these results we get improved lower bounds for ..."
Abstract

Cited by 782 (12 self)
 Add to MetaCart
We prove optimal, up to an arbitrary ffl? 0, inapproximability results for MaxEkSat for k * 3, maximizing the number of satisfied linear equations in an overdetermined system of linear equations modulo a prime p and Set Splitting. As a consequence of these results we get improved lower bounds
A Structural Approach to Operational Semantics
, 1981
"... Syntax of a very simple programming language called L. What is abstract about it will be discussed a little here and later at greater length. For us syntax is a collection of syntactic sets of phrases; each set corresponds to a different type of phrase. Some of these sets are very simple and can be ..."
Abstract

Cited by 1541 (3 self)
 Add to MetaCart
be taken as given: Truthvalues This is the set T = ftt; ffg and is ranged over by (the metavariable) t (and we also happily employ for this (and any other) metavariable sub and superscripts to generate other metavariables: t ; t 0 ; t 1k ).
Results 1  10
of
1,424,892