The paper deals with a quantitative analysis on the competitiveness of intermodal transport, based on Motorways of the Sea (MoS), in comparison with all-road transport. This analysis is applied to MoS routes connecting the Italian mainland with Sicily. The study involves: a detailed intermodal network model which compares monetary costs and travel times from all relevant origins in the mainland to all relevant destinations in Sicily; and a survey carried out at some representative trucking firms operating to / from Sicily. The aim of the interviews has been: on one side to make a comparison between the theoretical and actual mode of transport and routes taken, and in case they are different, to understand the reasons of the discrepancy; on the other side to determine what are the main aspects taken into account by trucking companies in their modal choice, in order to understand how the competiveness of MoS against road transport can be improved. The results of the analysis show that the modal choice is affected by several elements: monetary costs and travel times; reliability of MoS routes; availability of MoS routes; MoS routes frequencies; but it resulted from the interviews that monetary costs and travel times are the most important factors considered by trucking companies in the modal and route choice. This study has also shown that an improvement of MoS routes on the Italian Adriatic side is necessary: actually, a strong reason for which in Italy MoS traffic is still a small percentage of road traffic is the low number of MoS routes currently in operation and their low frequency. This analysis could help decision makers, and maritime operators, to efficiently invest in the improvement of MoS routes. Moreover, this analysis, developed for an Italian case study, can be applied to other European and Mediterranean scenarios.
Traditional car sharing systems are round trip shared vehicle systems and require advance reservations. The advances of GPS, communication techniques and vehicle automation allow us to improve car-sharing systems and to provide users with greater flexibility. As it concerns reservation, new car sharing systems offer users open-ended reservation and/or instant access. As it concerns the trip topology, new car sharing systems are multiple station shared vehicle systems (MSSVS). Round trips still occur in this type of system; however there are a large number of one-way trips made between the multiple stations. Operating an MSSVS is much more difficult than operating a round trip shared vehicle system. The problem is that the system can quickly become imbalanced with respect to the number of vehicles at the multiple stations. A review of user-based and operator-based relocation strategies is provided in the paper, as well as some details about some new possible car sharing systems, where vehicles are fully automated and can be accessed from any point within the intervention area.
Purpose The paper concerns a transport system for pedestrian areas, based on a fleet of fully-automated Personal Intelligent Accessible Vehicles. The following services are provided: instant access, open ended reservation and one way trips. All these features provide users with high flexibility, but create a problem of uneven distribution of vehicles among the stations. A fully vehicle based relocation strategy is proposed: when a relocation is required vehicles automatically move among stations. The paper focuses on a methodology that allows to plan the proposed transport system for wide pedestrian areas. The methodology aims to determine the fleet dimension and the relocation strategy parameters which minimize the system cost. The system cost takes into account the level of service and the efficiency. Relocation strategy parameters define when and among which stations relocations should be performed. Methods The problem faced is an optimisation problem where the search space is defined by all the possible fleet dimensions and relocation strategy parameters. As this cost function could be a multipeak function and since the search space is discrete and extremely large, a random search algorithm has been adopted. Because of the characteristics of the problem, a parallel optimization technique was required. Given a fleet dimension and relocation strategy parameters, a microsimulator models the activity of each user, as well as the activity of each vehicle over time with the aim of finding the level of service and the system efficiency.Results, conclusions and application The methodology has been applied to planning the proposed transport system for the centre of Barreiro, Portugal.
Purpose The paper refers to an innovative urban freight distribution scheme, aimed at reducing the externalities connected with the freight delivery process. Both packages destined to commercial activities and to end consumers (e-commerce) are taken into account. Each package is characterized by an address and dimensions. In the proposed transport system, freight is firstly delivered to the UDC on the border of urban areas through trucks or trains which perform the long distance transport. After, freight is reorganized and consolidated into load units, i.e. the FURBOT boxes, according to packages dimensions and to the addresses of receivers. Each box is addressed to a temporary unloading bay and it is delivered there by a FURBOT vehicle. The receivers are in charge of collecting their packages in the related unloading bays where they have been delivered. Methods and results The paper concerns a methodology for optimizing this freight transport system's performances. The overall methodology receives in input the actual freight demand and the road network, and finds the transport system parameters (number of required FURBOT boxes, their temporary unloading bay, the FURBOT fleet dimension and the FURBOT vehicle routing) that minimize the system overall cost. The overall cost is a sum of the users' cost, which depends on the distance they have to walk for collecting their packages in the FURBOT box, and of the operator's cost, which depends on the number of required boxes, the total distance travelled by the FURBOT vehicles and the required number of FURBOT vehicles. Application The overall procedure has been applied to the case study of Barreiro old town, a suburb of Lisbon, Portugal.
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