In the surface mining industry, the Equipment Selection Problem involves choosing an appropriate fleet of trucks and loaders such that the long-term mine plan can be satisfied. An important characteristic for multi-location (multi-location and multi-dumpsite) mines is that the underlying problem is a multi-commodity flow problem. The problem is therefore at least as difficult as the fixed-charg...

Flow cover inequalities are among the most effective valid inequalities for capacitated fixed-charge network flow problems. These valid inequalities are based on implications for the flow quantity on the cut arcs of a two-partitioning of the network, depending on whether some of the cut arcs are open or closed. As the implications are only on the cut arcs, flow cover inequalities can be obtaine...

Capacitated network design is a crucial problem to telecommunications network planners. In this paper we consider the Multi-Level Capacitated Minimum Spanning Tree Problem (MLCMST), a generalization of the well-known Capacitated Minimum Spanning Tree Problem. We present a genetic algorithm, based on the notion of grouping, that is quite effective in solving large-scale problems to within 10% of...

We consider the reliable multi configuration capacitated logistics network design problem (RMCLNDP) with system disruptions, concerned with facilities locating, transportation links constructing, and also allocating their limited capacities to the customers in order to satisfy their demands with a minimum expected total cost (including locating costs, link constructing costs, as well as expecte...

We improve the mixed-integer programming formulation of the multicommodity capacitated fixed-charge network design problem by incorporating valid inequalities into a cutting-plane algorithm. We use five classes of valid inequalities: the strong, cover, minimum cardinality, flow cover, and flow pack inequalities, the last four being expressed in terms of cutsets of the network. We develop effici...

The Multi-Commodity Capacitated Multi-facility Weber Problem (MCMWP) is concerned with locating I capacitated facilities in the plane to satisfy the demand of J customers for K commodities with the minimum total transportation cost. The MCMWP is a non-convex optimization problem. Customer locations, demands and capacities for each commodity are known a priori. The transportation costs, which de...

Capacitated fixed-charge network flows are used to model a variety of problems in telecommunication, facility location, production planning and supply chain management. In this paper, we investigate capacitated path substructures and derive strong and easy-to-compute path cover and path pack inequalities. These inequalities are based on an explicit characterization of the submodular inequalitie...

closed-loop supply chain network design is a critical issue due to its impact on both economic and environmental performances of the supply chain. in this paper, we address the problem of designing a multi-echelon, multi-product and capacitated closed-loop supply chain network. first, a mixed-integer linear programming formulation is developed to maximize the total profit. the main contribution...

We study a cement transportation problem with asset-management (equipment selection) for strategic planning scenarios involving multiple forms of transportation and network expansion. A deterministic mixed integer programming approach is difficult due to the underlying capacitated multi-commodity network flow model and the need to consider a time-space network to ensure operational feasibility....