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...

We present a general framework for modeling routing problems based on formulating them as a traditional location problem called the Capacitated Concentrator Location Problem. We apply this framework to two classical routing problems: the Capacitated Vehicle Routing Problem and Inventory-Routing Problem. In the former case, the heuristic is proven to be asymptotically optimal for any distributio...

In the classical maximal flow problem, the objective is to maximize the supply to a single sink in a capacitated network. In this paper we consider general capacitated networks with multiple sinks: the objective is to optimize a general "concave" preference relation on the set of feasible supply vectors. We show that an optimal solution can be obtained by a marginal allocation procedure. An eff...

In this work we address a capacitated hub problem arising from a Telecommunications application. In this problem we must choose the routes and the hubs to use in order to send a set of commodities from sources to destinations in a given capacitated network with a minimum cost. The capacities and costs of the arcs and hubs are given, and the graph connecting the hubs is not assumed to be complet...

We develop a two stage model of a manufacturing supply chain. This two stage production transportation model features capacitated production in two stages, and a fixed cost (or concave cost) for transporting the product between the stages. We prove several properties of this model, which we call the Two Stage Production Distribution Problem (2SPDP) model. By placing “non-speculative” assumption...

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...

The present paper, discuss one of the most challenging subjects for the management namely production planning. It appears to be a hierarchical process ranging from long to medium to short term decisions. Production planning models are divided into two categories which are capacitated and uncapacitated. This paper reviews the literature on singlelevel single-resource lotsizing models and provide...

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...