This paper presents a polynomial time algorithm used for solving a Mixed Integer Linear Program (MILP) formulation of a scheduling problem applicable to Air Traffic Control. We first relate the general MILP (which we believe to be NP-Hard) to the Air Traffic Control problem, which consists of performing maneuver assignments to achieve scheduling constraints for airport arrival traffic. This MIL...

We investigate the optimization of transport routes of barge container ships with the objective to maximize the profit of a shipping company. This problem consists of determining the upstream and downstream calling sequence and the number of loaded and empty containers transported between any two ports. We present a mixed integer linear programming (MILP) formulation for this problem. The probl...

Large-scale supply chain design problems are generally intractable when input as single entities to general purpose branch-and-bound solvers such as CPLEX. In this research we demonstrate that the nested partition (NP) method is capable of efficiently producing very high quality solutions to large-scale supply chain problems by taking advantage of their structure to generate an appropriate set ...

The Hop-constrained Minimum cost Flow Spanning Tree (HMFST) problem is an extension of the Hop-Constrained Minimum Spanning Tree problem since it considers flow requirements other than unit flows. Given that we consider the total costs to be nonlinearly flow dependent with a fixed-charge component and given the combinatorial nature of this class of problems, we propose a heuristic approach to a...

We present a parametric approach for solving fixed-charge problems first sketched in Glover (1994). Our implementation is specialized to handle the most prominently occurring types of fixed-charge problems, which arise in the area of network applications. The network models treated by our method include the most general members of the network flow class, consisting of generalized networks that ...

School bus routing problem has been a significant concern of most people related to school and school bus system as one of vehicle routing problems. Making an appropriate problem formulation depends on how to reflect the realities of the problem. And, as the problem scope becomes wider, the problem can’t be solved only with the exact methods. So, there is need to develop an efficient heuristic ...

The cellular network design (CND) problem is formulated as a comprehensive linear mixed integer programming model integrating the base station location (BSL) problem, the frequency channel assignment (FCA) problem and the topological network design (TND) problem. A solution algorithm based on Lagrangean relaxation is proposed for solving this complex cellular network design problem. Pursuing th...

W multiplexing (WDM) is the best technology currently available to handle the rapidly increasing demand for bandwidth in fiber-optical telecommunications networks. In a WDM wavelengthrouted network, end users communicate with one another using all-optical channels called lightpaths. Such lightpaths are used to support point-to-point connections and may span multiple fiber links. In the absence ...