Incomplete Single Assignment Hierarchical Hub Median Problem with/without Network Flow Consideration

Abstract

In this paper we present the problem of designing a three level hub median network. In our network, the top level consists of an incomplete network where a direct link between all central hubs is not necessary and an incomplete network may lead to having lower total costs. The second and third levels are consisted of star networks that connect the hubs to central hubs and the demand nodes to hubs and thus to central hubs, respectively. We also propose a hierarchical hub median problem with single assignment where there are no flows among nodes and the transportation costs depends on the distance between nodes. We analyze this problem in both complete and incomplete network among central hubs, and propose mathematical models for both problems.We conduct computational studies for these three developed models by using the CAB data.Hubs are facilities that serve as points for switching, transshipment and sorting flows in many-to-many distribution systems. In a particular hub location problem the objective is to determine locations of hubs and also assigning other nodes to these hubs with minimum distribution costs.