In contrast to p-hub problems with a summation objective (p-hub median), minmax hub problems (p-hub center) have not attained much attention in the literature. In this paper, we give a polyhedral analysis of the uncapacitated single allocation p-hub center problem (USApHCP). The analysis will be based on a radius formulation which currently yields the most efficient solution procedures. We show...

The hub median problem is to locate hub facilities in a network and to allocate non-hub nodes to hub nodes such that the total transportation cost is minimized. In the hub center problem, the main objective is one of minimizing the maximum distance/cost between origin destination pairs. In this paper, we study uncapacitated hub center problems with either single or multiple allocation. Both pro...

These papers are produced by Cambridge Judge Business School, University of Cambridge. They are circulated for discussion purposes only. Their contents should be considered preliminary and are not to be quoted without the authors' permission. The stochastic uncapacitated single allocation p-hub center problem is an extension of the deter-ministic version which aims to minimize the longest origi...

In this paper an uncapacitated multiple allocation p-hub median problem is discussed. The model minimizes the transportation cost based on inventory service level at hubs through double paths between hubs. Inventory service level is defined as the percent of inventory shortage of vehicles at hubs according to passengers demand and replenishment time of vehicles. A real data from 25 nodes of mun...

A p-hub center network design problem is definition of some nodes as hubs and allocation of non-hub nodes to them wherein the maximum travel times between any pair of nodes is minimized. The distinctive feature of this study is proposing a new mathematical formulation for modeling costs in a p-hub center problem. Here, instead of considering costs as a linear function of distance, for the first...

This paper proposes a new lower bounding procedure for the Uncapacitated Single Allocation p-Hub Median Problem based on Lagrangean relaxation. For solving the resulting Lagrangean subproblem, the given problem structure is exploited: it can be decomposed into smaller subproblems that can be solved efficiently by combinatorial algorithms. Our computational experiments for some benchmark instanc...

The present paper deals with a variant of hub location problems (HLP): the uncapacitated single allocation p-Hub median problem (USApHMP). This consists to jointly locate facilities and allocate demand nodes these selected facilities. objective function is minimize routing demands between any origin destination pair nodes. known be NP-hard. Based on artificial immune systems (AIS) framework, th...

In this paper we propose several heuristics for the Uncapacitated -Allocation -Hub Median Problem. In the classical -hub problem, given a set of nodes with pairwise traffic demands, we must select of them as hub locations and route all traffics through them at a minimum cost. We target here an extension, called the -allocation -hub median problem, recently proposed by Yaman (2011), in which eve...