In this paper we present a 1.52-approximation algorithm for the metric uncapacitated facility location problem, and a 2-approximation algorithm for the metric capacitated facility location problem with soft capacities. Both these algorithms improve the best previously known approximation factor for the corresponding problem, and our soft-capacitated facility location algorithm achieves the inte...

This paper presents a fuzzy approach to capacitated flow shop scheduling problem. Fuzzy sets are applied to express the flexible constraints on capacity of each period in the scheduling horizon. Fuzzy sets are also used to model the processing times of jobs and the setup times of machines required when a new job starts processing. Demand is set for each period. Over production incurs the holdin...

Two of the most complex activities in production and operations management (POM) are inventory planning and operations scheduling. This chapter presents two problems related to these activities, namely, the capacitated lot-sizing and scheduling problem and the capacitated vehicle routing problem. For each of these problems, the authors discuss several solution methods, present a competitive gen...

This paper presents an approximate algorithm based on distributed learning automata for solving capacitated vehicle routing problem. The vehicle routing problem (VRP) is an NPhard problem and capacitated vehicle routing problem variant (CVRP) is considered here. This problem is one of the NP-hard problems and for this reason many approximate algorithms have been designed for solving it. Distrib...

We develop a simple and practical exact algorithm for the problem of locating p facilities and assigning clients to them within capacity restrictions in order to minimize the maximum distance between a client and the facility to which it is assigned (capacitated p-center). The algorithm iteratively sets a maximum distance value within which it tries to assign all clients, and thus solves bin-pa...

We introduce the multiple capacitated job shop scheduling problem as a generalization of the job shop scheduling problem. In this problem machines may process several operations simultaneously. We present an algorithm based on constraint satisfaction techniques to handle the problem e ectively. The most important novel feature of our algorithm is the consistency checking. An empirical performan...

The Capacitated Arc Routing Problem with Refill Points (CARP-RP) is a new variant of the Capacitated Arc Routing Problem (CARP). In a CARP situation, the vehicle servicing arcs has a finite capacity, and hence has to return to the depot or a secondary station to be refilled (or emptied). In contrast, in the CARP-RP, the vehicle servicing arcs must be refilled on the spot by using a second vehic...

Mixed Capacitated Arc Routing Problem (MCARP) models arise in distribution or collecting problems where activities are performed by vehicles, with limited capacity, and are continuously distributed along some predefined links (routes, streets) of an associated network. Considering directed as well as undirected required links, it is a generalization of the well known Capacitated Arc Routing pro...

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...