The m-Center Problem: Minimax Facility Location

The m-Center Problem is to locate a given number of (emergency) facilities anywhere along a road network so as to minimize the maximum distance between these facilities and fixed demand locations assigned to them. Fundamental properties of the m-Center Problem are examined. The problem is modeled using integer programming, and is successfully attacked using a binary search technique and a combination of exact tests and heuristics. Computational results are given.

Note--A Note on El-Shaieb's New Algorithm for Locating Sources Among Destinations

The objective of this note is (i) to identify and briefly review some references not included in [El-Shaieb, A. M. 1973. A new algorithm for locating sources among destinations. Management Sci. 20 221-231.] as well as more recent additions and (ii) to give computational comparisons of three other solution methods with that of El-Shaieb on his 30-city test data.

Efficient Production-Distribution System Design

The production-distribution system design is an integral part of the general supply chain design. This paper proposes a novel solution methodology for this problem that is based on Lagrangean relaxation, interior-point methods, and branch and bound. Unlike classical approaches, Lagrangean relaxation is applied in a two-level hierarchy, branch and bound is based on a Lagrangean lower bound and column generation (branch and price), while interior-point methods are used within a cutting-plane context (analytic centre cutting-plane method---ACCPM). Numerical results demonstrate that the two-level approach outperforms the classical approach and provides a very sharp lower bound that is the (proven) optimal in most cases.production-distribution systems, Lagrangean relaxation, nested decomposition, interior-point cutting-plane methods, branch and price