We present a branch-and-cut algorithm to solve capacitated network design problems. Given a capacitated network and point-to-point traac demands, the objective is to install more capacity on the edges of the network and route traac simultaneously, so that the overall cost is minimized. We study a mixed-integer programming formulation of the problem and identify some new facet deening inequaliti...

This paper proposes a perturbation-based heuristic for the capacitated multisource Weber problem. This procedure is based on an effective use of borderline customers. Several implementations are considered and the two most appropriate are then computationally enhanced by using a reduced neighbourhood when solving the transportation problem. Computational results are presented using data sets fr...

increasing urban network has both positive (accessibility) and negative (air pollution) impacts. in this research air quality is chosen as key elements with respect to their critical roles in quality of life and urban health. the overall objective of this study is to develop a mathematical model to plan appropriate locations for residential land uses and urban transportation network development...

This work deals with a multi-period capacitated location problem inspired by telecommunication access network planning problems, where demands and costs vary from one period to another. On each concentrator site, several capacitated concentrators can be installed at each period. Similarly, several capacitated modules can be installed at each period between each terminal and concentrator sites. ...

Transportation modes, including Walking and other private modes as well as transit services, provide travel options to the individual trip-maker along a transportation network. On a single basis, any modal option is featured here in terms of travel time to destination conditionally to immediate availability, expected wait time in the adverse case and the probability of availability. The paper i...

In this article we introduce the Quadratic Capacitated Vehicle Routing Problem (QCVRP), a combinatorial optimization problem that arises in practical applications in logistics and transportation. The QCVRP extends two other known problems, the Capacitated Vehicle Routing Problem (CVRP) and the Quadratic Symmetric Traveling Salesman Problem (QSTSP), the former by considering a modified cost matr...

A space-time network is used to model traffic flows over time for a capacitated road transportation system having one-way and two-way streets. Also, for the first time, traffic signal lights which change the network structure are explicitly incorporated into the model. A linear (time) cost per unit flow is associated with each arc, and it is shown that under the model structure, travel time on ...

Network design models are extensively used to represent a wide range of planning and operation management issues in transportation, telecommunications, logistics and production-distribution. In a very general sense, the problem consists of designing a network by selecting links to connect a set of nodes and to determine the amount of flow on each link such that the demand of each node for a num...