We study the General Routing Problem defined on a mixed graph and with stochastic demands. The problem under investigation is aimed at finding the minimum cost set of routes to satisfy a set of clients whose demand is not deterministically known. Since each vehicle has a limited capacity, the...

This paper deals with the probabilistic multi-vehicle pickup and delivery problem. We develop an efficient neighborhood evaluation procedure which allows to reduce the computational complexity by two orders of magnitude with respect to a straightforward approach. The numerical experiments...

The article deals with the methodologies for credit risk evaluation. It describes an empirical analysis carried out on a sample of Italian firms belonging to the leather manufacturing and wholesale industry. The study uses the efficiency, calculated through data envelopment analysis (DEA), and...

The Mixed Capacitated General Routing Problem (MCGRP) is defined over a mixed graph, for which some vertices must be visited and some links must be traversed at least once. The problem consists of determining a set of least-cost vehicle routes that satisfy this requirement and respect the...

This paper presents a hybrid metaheuristic for solving the static dial-a-ride problem with heterogeneous vehicles and fixed costs. The hybridization combines a reactive greedy randomized adaptive search, used as outer scheme, with a tabu search heuristic in the local search phase. The algorithm...

An optimization procedure for the optimal design of a trigenerative system to satisfy the energy needs of civil users is proposed. For the formulation of the mathematical model, it was necessary to refer to the class of MINLP (Mixed Integer Non Linear Programming Models), whose complexity is...