This paper presents a clustering-based approach to address a special case of the Capacitated Facility Location Problem (CFLP). The goal is to find the optimal locations of a finite set of facilities to satisfy the demands of a large set of fixed locations, while the sum of the demands at the point locations associated with the same facility cannot exceed its capacity. We develop a clustering-ba...

This paper addresses the independent multi-plant, multi-period, and multi-item capacitated lot sizing problem where transfers between the plants are allowed. This is an NP-hard combinatorial optimization problem and few solution methods have been proposed to solve it. We develop a GRASP (Greedy Randomized Adaptive Search Procedure) heuristic as well as a pathrelinking intensification procedure ...

Despite some successful applications of genetic algorithms (GAs) for solving the capacitated vehicle routing problems, they usually rely on problem-specific components or hybridization with other heuristics for obtaining competitive solutions. These problemspecific and hybridized characteristics complicate the GA implementation for solving reallife problems. In this paper, a pure GA for the cap...

The Capacitated m-ring-star Problem is a variant of the classical one-depot capacitated vehicle routing problem in which a customer is either on a route or is connected to another customer or to some Steiner point present in a route. We develop a new exact algorithm for this problem using a branch-and-cut-and-price approach and compare its performance with that of a branch-and-cut algorithm pro...

Facility-location problems have several applications in telecommunications, industrial transportation and distribution, etc. One of the most well-known facility-location problems is the p-median problem. This work addresses an application of the capacitated p-median problem to a real-world problem. We propose a genetic algorithm (GA) to solve the capacitated pmedian problem. The proposed GA use...

This abstract describes a branch, cut, and price (BCP) algorithm for the solution of a class of network design problems with routing and packing constraints that can all be seen as special cases of a general model we will call the Capacitated Node Routing Problem (CNRP). We present several alternative integer programming formulation of the CNRP that can be shown to generalize a number of other ...

This paper is focusing on an important transportation application encountered in supply chains, namely the capacitated two-stage fixed-charge transportation problem. For solving this complex optimization problem we described a novel hybrid heuristic approach obtained by combining a genetic algorithm based on a hash table coding of the individuals with a powerful local search procedure. The prop...

We propose a heuristic for a class of vehicle routing problems (VRPs) with minmax objective. These include the Capacitated VRP, the Capacitated VRP with multiple use of vehicles, and the Traveling Salesman Problem with multiple use of vehicles. A tabu search based adaptive memory procedure of instances indicate that the method produces very good solutions within reasonable computing times.

The successful application of Branch and Cut methods to the TSP has drawn attention also to the polyhedral properties of the symmetric capacitated vehicle routing problem, which is the capacitated counterpart of the TSP. We investigate three classes of valid inequalities for the CVRP, multistars, pathbin inequalities and hypotours and give computational results we obtained with a Branch and Cut...

Beyond Affinity Propagation: Message Passing Algorithms for Clustering Inmar-Ella Givoni Doctor of Philosophy Graduate Department of Computer Science University of Toronto 2012 Affinity propagation is an exemplar-based clustering method that takes as input similarities between data points. It outputs a set of data points that best represent the data (exemplars), and assignments of each non-exem...