In freight distribution services a required quality level may have a relevant effect on transportation costs. For this reason an evaluation tool is useful to compare different service settings and ...support the decision, on the base of quantitative indicators. This paper proposes a method for cost evaluation in this context and presents an application to a case study concerning a freight distribution service, which operates on a wide road network having a city centre, a peripheral urban area and a peri-urban rural zone. A simulation method is proposed to obtain real-life scenarios in order to test the method and its indicators. The performance of each indicator has been evaluated in an experimental context to produce realistic test cases, using a trip planning tool and a demand generator. First, the behaviour of the indicators is analysed with regard to the time windows width planned for the service. Then, their ability in estimating the total transportation cost to satisfy all the requests, under different time period profiles, is shown. The results confirm the ability of the set of indicators to predict with a good approximation the transportation costs and therefore to be used in supporting the service quality planning decisions.
This paper will present the Italian field operation test (FOT) to be performed within the European Project euroFOT, aimed at assessing a wide variety of intelligent transport systems (ITS) across ...Europe. This FOT is aimed at investigating an already marketed lane departure warning (LDW) equipped on the Lancia Delta vehicles, deploying a sample of up to 1000 vehicles, and using a wide and differentiated set of self-reported questionnaires. Results will be referred to LDW impact on traffic safety, usefulness, and driving behavior. Given the huge sample, results are expected to accurately depict the actual impact of this function.
This paper studies a set of indicators for evaluating how the quality of a freight distribution service with time windows, which operates on a given road network to satisfy a number of requests, ...affects the service cost. The result of a service quality setting, expressed as the width of the time windows, has been assessed using five indicators, which are a measure of the service operating costs and based on the request compatibility time interval. Each indicator's performance has been evaluated in an experimental context to produce realistic test cases, using a trip planning tool and a demand generator. The results confirm the ability of the selected indicators to predict with a good approximation the transportation costs and therefore to support the service quality planning decisions.
Multi-echelon distribution systems are quite common in supply-chain and logistic systems. They are used by public administrations in their transportation and traffic planning strategies as well as by ...companies to model their distribution systems. Unfortunately, the literature on com- binatorial optimization methods for multi-echelon distribution systems is very poor. The aim of this paper is twofold. Firstly, it introduces the family of Multi-Echelon Vehicle Routing Problems. Second, the Two-Echelon Capacitated Vehicle Routing Problem, is presented. The Two-Echelon Capacitated Vehicle Routing Problem (2E-CVRP) is an extension of the classical VRP where the delivery passes through intermediate depots (called satellites). As in the classical VRP, the goal is to deliver goods to customers with known demands, minimizing the total delivery cost while considering vehicle and satellites capacity constraints. A mathematical model for 2E-CVRP is presented and some valid in- equalities given, which are able to significantly improve the results on benchmark tests up to 50 customers and 5 satellites. Computational re- sults under different realistic scenarios are presented.
