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1.
Transportation - We show how data collected from a GPS device can be incorporated in motor insurance ratemaking. The calculation of premium rates based upon driver behaviour represents an...  相似文献   
2.

Freight transfer operations are critical in combined transport networks. In this paper a simulation model and modelling approach to the transfer of cargo between trains at rail terminals is presented. The model is used to study the Port-Bou terminal, the main intermodal terminal at the Spanish-French frontier. Four different gantry crane operation modes to interchange containers between trains are evaluated. These operation rules are tested in several scenarios to examine the critical factors of the system and the best operation rule for each situation. Latest generation software is used to develop the model that incorporates modular programming and enhanced graphic systems for output representation. It allows a dynamic display of the simulated system and, likewise, the possibility of developing modules that can be reused in other studies. The research shows how simulation can be a useful planning tool in the rail transportation context.  相似文献   
3.
Despite European Union (EU) political support to identify the most feasible Motorways of the Sea, the final decision can only be made by Private Shipping Companies, which are operators of a unique stretch of the intermodal chain. This paper provides a multi-criteria decision method to identify the most suitable Motorways of the Sea taking into account the competitiveness of whole intermodal routes versus the alternative of road transport from the loader’s perspective. The analysis is carried out assuming a ‘many-to-many’ transport model. Firstly indexes of time and cost were defined and evaluated for every available route in the model in accordance with a multi-criteria decision matrix. Secondly, through a Monte Carlo simulation a sensitivity analysis was carried out in order to evaluate the influence on the results of the forecast assumed to construct the matrix. The results obtained are not only quantitative, but also qualitative. The development of intermodal routes via Motorways of the Sea is especially relevant for the peripheral EU countries. Due to the relevance of the freight flow between France and Spain and the congestion of their connections through the Pyrenees, the method proposed was applied to the analysis of this particular case  相似文献   
4.
The analysis of complex networks has been carried out in different fields using an ample variety of method and concepts. Recently, in the general literature of regional economics, the concepts of resilience, connectivity, vulnerability and criticality have been gaining their momentum. The aim of this paper is to provide an analytical framework, using well-known accessibility indicators, in order to calculate the critical links or road sections of the Spanish high-capacity road network. Our analysis will be based on approximately four hundred sections that will be classified in five different groups according to their criticality degree in the whole network. Our analysis will be complemented with the comparison of the results obtained in five different scenarios, namely the average criticality using the effects on the whole country, Madrid, Barcelona, Valencia and Pontevedra. Furthermore, the paper will also analyze what kind of intrinsic characteristics of the sections favor or not the links’ criticality using a method based on a classification and regression tree. This analysis is crucial to understand other important concepts that are recently being studied in network and spatial economics, like, for example, resilience and vulnerability. It is concluded that the number of relations or routes, being a trunk or not, the road density and the time to Madrid capital play an important role in the criticality of the roads section in the high capacity road network.  相似文献   
5.
The City of Madrid is putting into operation Intermodal Exchange Stations (IESs) to make connections between urban and suburban transportation modes easier for users of public transportation. The purpose of this article is to evaluate the actual effects that the implementation of IESs in the City of Madrid has on the affected stakeholders: users, public transportation operators, infrastructure managers, the government, the abutters and other citizens. We develop a methodology intended to help assess the welfare gains and losses for each stakeholder. Then we apply this methodology to the case study of the Avenida de América IES in the city of Madrid. We found that it is indeed possible to arrive at win?Cwin solutions for the funding of urban transportation infrastructure, as long as the cost-benefit ratio of the project is high enough. Commuters save travel time. Bus companies diminish their costs of operation. The abutters gain in quality of life. The private operator of the infrastructure makes a fair profit. And the government is able to promote these infrastructure facilities without spending more of its scarce budgetary resources.  相似文献   
6.
We have studied the physicochemical and biological structure of a permanent filament off Cape Ghir (31°N) and estimated the transport of organic matter associated with it. The seaward filament exported coastal upwelled water, with low temperature and salinity and high organic matter, to the open ocean even in the absence of upwelling-favorable conditions. The estimated flux of excess organic carbon (the nonrefractory pool) expressed in annual basis yielded a value of 3.1×109 kg C, from which 90% was transported as dissolved organic carbon. This flux represents about 63% of the average annual primary production for the region of study. We conclude that the net-offshore transport may contribute to the enrichment of offshore oligotrophic waters throughout the year, partly explaining the metabolic imbalance found in open ocean waters of the subtropical Northeast Atlantic.  相似文献   
7.
During the seasonal stratification of 1983 and 1984, intensive sampling of the shelf region of the northeast Spanish coast was carried out. This unique dataset is used to define the most salient features of the shelf water dynamics. We show that region has a strong spatial and temporal variability associated with the southward spreading of continental waters from the Rhone river, in the northern gulf of Lyons. Southward spreading begins in early spring and was particularly obvious during June 1983 when strong horizontal density gradients were observed. Spreading almost completely disappears in August when observed upper layer salinities are uniform. We also show that significant shelf/slope water exchange takes place associated with the abrupt topographic canyons found in the region. In particular we observed in June 1983 a small positive geostrophic vorticity region at the Palamós canyon while a larger anticyclonic eddy was observed over the shelf south of this canyon. The biological implications of these two features have been demonstrated. We conclude indicating that in this region where no dominant winds exist, the shelf water dynamics is dominated by the southward spreading of low salinity continental waters and by the intrusion of high salinity open ocean water through submarine canyons.  相似文献   
8.
In order to safely maintain a vehicle, it is necessary to verify the most important systems that affect safety during Periodic Motor Vehicle Inspections (PMVIs). In a previous paper, a test method and validation criteria were suggested by the authors to verify shock absorber status during PMVIs, as they are a fundamental component that may wear out during a vehicle’s life. In this paper, variations of the performance of the vehicle’s brakes resulting from shock absorber wearing have been analyzed, in order to confirm whether the suggested criteria is valid for taking into account longitudinal forces and pitch movement on the vehicle. A simulation-based study was conducted with several configurations of a worn damper on a vehicle driving on two virtual roads: smooth and undulating. The results confirmed that the damping coefficient established as an acceptable value to verify the shock absorber status in PMVIs is also valid considering the forces involved in a braking maneuver.  相似文献   
9.
Artificial islands have been constructed next to large cities due to the need for extra space in highly populated areas. These emerged structures have been used by many countries as platforms for developing infrastructure (airports, harbors, highways, etc.), rebuilding ecological areas, and creating new spaces for tourism or residential areas. In this study, two state-of-the-art numerical models for wave propagation and nearshore circulation are used to simulate the effects of an emerged artificial island on the Barcelona coast. Several sea indicators (wave height, intensity and direction of currents, and mean water level) are analyzed to assess the changes likely to be induced by an artificial island. Three different situations are studied and the indicators are compared across the different tests to obtain information that can be used in the planning process of these structures. In two-meter wave conditions, the tests show that wave height is generally reduced in the sheltered area, which leads to improved safety for beach users (bathing is prohibited when wave height exceeds the two-meter threshold). However, the numerical models also reveal that velocities in the sheltered area usually decrease, which must be controlled to prevent stagnation in the bathing area.  相似文献   
10.
Vehicle systems such as the steering, brakes and suspension greatly influence vehicle safety. Therefore, these systems must be inspected to guarantee that they are functioning correctly and to certify that the vehicle is functioning at a satisfactory safety level. In disc brakes, warping is one of the principal reasons for vibrations and noise, and it contributes to diminished brake efficiency. Currently, the International Motor Vehicle Inspection Committee (CITA) demands disc brake warping inspections occur during periodic motor vehicle inspections (PMVIs); however, the procedure to carry out this inspection is not well defined. In this investigation, the warping phenomenon has been analyzed, and a new inspection procedure is proposed.  相似文献   
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