Operations Research Transactions ›› 2012, Vol. 16 ›› Issue (1): 13-20.

• Original Articles • Previous Articles     Next Articles

An Approximation Agorithm for the Stochastic Fault-Tolerant Fcility Placement Problem

SHAO  Jiating1,   Xu Dachuan1   

  1. 1. Department of Applied Mathematics, Beijing University of Technology, Beijing 100124, China
  • Received:2011-09-23 Revised:2011-12-19 Online:2012-03-15 Published:2012-03-15
  • Supported by:

    This work is supported by The National Science Foundation of China (No. 11071268), Scientific Research Common Program of Beijing Municipal Commission of Education (No. KM201210005033), and PHR(IHLB).

Abstract: In the deterministic fault-tolerant facility placement problem (FTFP),  we are given a set of locations  and a set of clients. We can open any number of different facilities with the same opening cost at each location. Each client j has an integer requirement rj. Connecting  client j to different facilities at the same location is permitted. The objective is to open some facilities and connect each client j to rj different facilities such that the total cost is minimized. In this paper, we consider the two-stage stochastic fault-tolerant facility placement problem (SFTFP)  with recourse in which the set of clients are unknown in advance. But there are finite scenarios materialized by a probability distribution. Each scenario specifies a subset of clients to be assigned. Moreover, each facility has two kinds of opening cost. In the first stage, we open a subset of facilities according to the stochastic information of the clients. In the second stage, we can open additional number of facilities when the actual information of the clients is revealed. We give a linear integral program and an LP-rounding based 5-approximation algorithm for the SFTFP.

Key words: facility placement problem, approximation algorithm, LP-rounding