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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2007.11.027 Byline: Souheyl Touhami (a), Jean-Marie Bourjolly (a), Gilbert Laporte (b) Keywords: OR in telecommunications; Tabu search; Antenna positioning; Frequency allocation; GSM Abstract: In this article we propose to partially integrate the antenna positioning (APP) and frequency allocation problems (FAP). The traditional wireless network design process examines these two major issues sequentially in order to avoid the very high complexity associated with the simultaneous resolution of the two problems. The proposed integration involves the introduction of interference protection guarantees within the APP. It is customary to define such guarantees in an intermediate step and to use them as input to FAP, in order to protect against interference in critical areas. The proposed approach consists of selecting these protections while solving the APP, allowing the optimization procedure to exploit the degrees of freedom that this would offer. Results on two real-life problem instances indicate a significant improvement in interference levels and resource utilization. Author Affiliation: (a) Center for Research on Transportation and Universite du Quebec a Montreal, Canada (b) Canada Research Chair in Distribution Management, Center for Research on Transportation, and HEC Montreal, Canada Article History: Received 4 July 2005; Accepted 5 November 2007

The researchers report they have proved that the maximum k-club problem (MkCP) defined on an undirected graph is NP-hard. As part of their research, they used an integer programming formulation.

A modification of the branch-and-bound algorithm for the tree assembly line balancing problem in flexible manufacturing systems for several products is proposed. The model has an improved lower-bounding procedure and a stronger partitioning scheme. Application of the model allows the minimization of the number of work stations needed to manufacture a variety of products requiring sequential nonpreemptive tasks, some of which are shared by different products.

This paper presents a tabu-search heuristic for the capacitated lot-sizing problem (CLSP) with set-up carryover. This production-planning problems allows multiple items to be produced within a time period, and setups for items to be carried over from one period to the next. Two interrelated decisions, sequencing and lot sizing, are present in this problem. Our tabu-search heuristic consists of five basic move types--three for the sequencing decisions and two for the lot-sizing decisions. We allow infeasible solutions to be generated at a penalty during the course of the search. We use several search strategies, such as dynamic tabu list, adaptive memory, and self-adjusting penalties, to strengthen our heuristic. We also propose a lower-bounding procedure to estimate the quality of our heuristic solution. We have also modified our heuristic to produce good solutions for the CLSP without set-up carryover. The computational study, conducted on a set of 540 test problems, indicates that on average our heuristic solutions are within 12% of a bound on optimality. In addition, for the set of test problems our results indicate an 8% reduction in total cost through set-up carryover., 1. Introduction In this paper, we present a tabu-search heuristic for a single-level, multi-item, capacitated lot-sizing problem (CLSP) with set-up carryover. The lot-sizing problem we are considering involves the production [...]