Hierarchical multimodal hub location problem is a cost-minimizing hub covering problem where two types of hubs and hub links, accounting for ground and air transportation, are to be established, while ensuring time-definite deliveries. We propose a mixed-integer programming formulation and perform a comprehensive sensitivity analysis on the Turkish network. We show that the locations of airport...

This paper presents a study on reliable single and multiple allocation hub-and-spoke network design problems where disruptions at hubs and the resulting hub unavailability can be mitigated by backup hubs and alternative routes. It builds nonlinear mixed integer programming models and presents linearized formulas. To solve those difficult problems, Lagrangian relaxation and Branch-and-Bound meth...

The hub location problem with single assignment is the problem of locating hubs and assigning the terminal nodes to hubs in order to minimize the cost of hub installation and the cost of routing the traffic in the network. There may also be capacity restrictions on the amount of traffic that can transit by hubs. The aim of this paper is to investigate polyhedral properties of these problems and...

Hubs are special centers that used for switching, transferring and handling freight or passengers in transportation systems. The hub location problem deals with locating hub facilities and allocating demand nodes to hubs in order to route the traffic between origin–destination pairs. Aiming at minimizing the total costs, maximizing utilization of transporters, maximizing the service level, etc....

This paper deals with hub-and-spoke network design in the liner shipping sector. It introduces a capacitated directed cycle hub location and cargo routing problem under congestion. The involves four decisions: of ports; allocation non-hub ports to construction cyclic route at port level; between all origin-destination demand pairs network. objective is minimize cost which includes fixed opening...

This paper studies capacitated single-allocation hub covering location problem with fuzzy cover radius and travel time. Objective of hub covering problem is to find the minimum number of hubs considering the maximum allowable travel time. Computational results show that due to uncertainty, number of hubs and the allocation of non-hub nodes to hub nodes are changed. This paper proposes heuristic...

This paper studies a reliable facility location problem with facility protection that aims to hedge against random facility disruptions by both strategically protecting some facilities and using backup facilities for the demands. An Integer Programming model is proposed for this problem, in which the failure probabilities of facilities are site-specific. A solution approach combining Lagrangian...

in this study, a hierarchical hub location problem by considering different modes of transportation and maximum allowed delay is investigated. this study is done on iran’s express postal service with 2 days maximum delay in delivery considering ground and airport hubs. the problem is of the type of location and single allocation for collection, transfer and distribution of the shipments. all th...