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SODA
2012
ACM
297views Algorithms» more  SODA 2012»
12 years 1 months ago
Constant factor approximation algorithm for the knapsack median problem
We give a constant factor approximation algorithm for the following generalization of the k-median problem. We are given a set of clients and facilities in a metric space. Each fa...
Amit Kumar
SODA
2012
ACM
225views Algorithms» more  SODA 2012»
12 years 1 months ago
Approximating rooted Steiner networks
The Directed Steiner Tree (DST) problem is a cornerstone problem in network design. We focus on the generalization of the problem with higher connectivity requirements. The proble...
Joseph Cheriyan, Bundit Laekhanukit, Guyslain Nave...
ISPD
2012
ACM
283views Hardware» more  ISPD 2012»
12 years 7 months ago
Low-power gated bus synthesis for 3d ic via rectilinear shortest-path steiner graph
In this paper, we propose a new approach for gated bus synthesis [16] with minimum wire capacitance per transaction in three-dimensional (3D) ICs. The 3D IC technology connects di...
Chung-Kuan Cheng, Peng Du, Andrew B. Kahng, Shih-H...
ICALP
2011
Springer
13 years 3 months ago
Improved Approximation for the Directed Spanner Problem
We present an O( √ n log n)-approximation algorithm for the problem of finding the sparsest spanner of a given directed graph G on n vertices. A spanner of a graph is a sparse ...
Piotr Berman, Arnab Bhattacharyya, Konstantin Maka...
ICALP
2011
Springer
13 years 3 months ago
Steiner Transitive-Closure Spanners of Low-Dimensional Posets
Given a directed graph G = (V, E) and an integer k ≥ 1, a Steiner k-transitive-closure-spanner (Steiner k-TC-spanner) of G is a directed graph H = (VH , EH ) such that (1) V ⊆ ...
Piotr Berman, Arnab Bhattacharyya, Elena Grigoresc...
ACL
2009
13 years 9 months ago
Concise Integer Linear Programming Formulations for Dependency Parsing
We formulate the problem of nonprojective dependency parsing as a polynomial-sized integer linear program. Our formulation is able to handle non-local output features in an effici...
André L. Martins, Noah A. Smith, Eric P. Xi...
ORL
2008
91views more  ORL 2008»
13 years 11 months ago
On the integrality ratio for tree augmentation
We show that the standard linear programming relaxation for the tree augmentation problem in undirected graphs has an integrality ratio that approaches 3 2 . This refutes a conjec...
Joseph Cheriyan, Howard J. Karloff, Rohit Khandeka...
COR
2007
108views more  COR 2007»
13 years 11 months ago
A hub location problem with fully interconnected backbone and access networks
This paper considers the design of two-layered fully interconnected networks.A two-layered network consists of clusters of nodes, each defining an access network and a backbone n...
Tommy Thomadsen, Jesper Larsen
COR
2007
105views more  COR 2007»
13 years 11 months ago
Stabilized column generation for highly degenerate multiple-depot vehicle scheduling problems
Column generation has proven to be efficient in solving the linear programming relaxation of large scale instances ofthemultiple-depotvehicleschedulingproblem(MDVSP).Howeverdif...
Amar Oukil, Hatem Ben Amor, Jacques Desrosiers, Hi...
DISOPT
2008
85views more  DISOPT 2008»
13 years 11 months ago
How tight is the corner relaxation?
Given a mixed-integer linear programming (MILP) model and an optimal basis of the associated linear programming relaxation, the Gomory's corner relaxation is obtained by drop...
Matteo Fischetti, Michele Monaci