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Abstract

The institutional environment of rail transport has changed as a result of recent European directives, but the changes have taken different forms from one country to another. In the case of international maritime chains, the development of door‐to‐door services makes inland haulage from the loading and discharging ports extremely important, and it highlights the need to reshape the rail freight industry. This paper analyses the degree of involvement of different actors drawn from the maritime industry in developing and commercializing rail services in the changing regulatory environment. Several maritime operators, shipping lines, port‐handling companies and port authorities have been involved in some container rail services since the early days of liberalization. Their commitments take very different forms, however. Whereas contracts are mainly used for the provision of service, particularly for train haulage, integration by means of shareholding or creating subsidiaries or joint ventures is used for marketing. Important differences between France, the UK, Germany and the Netherlands are detailed. In the latter two countries, there is more involvement in the provision of rail services. Marketing rail services appear to be the main strategic issue for the maritime operators in all four countries  相似文献   
2.
The ports of Mediterranean basin have experienced significant growth in container traffic over the last decade. In the western Mediterranean two distinct types of port have emerged: the established ports of the northern part of the basin which serve a gateway function and a set of new ports in the south which act as transhipment hubs. In this paper we explore the dynamics of change and reveal how growth is driven by shifts in individual trades. While the hub ports are integrated into Asian pendulum services, the gateway ports are experiencing growth because of new direct services to Asia and North America. We suggest that the distinctions between the transhipment hubs and the gateway ports are becoming blurred, especially because the gateway ports are also assuming greater transhipment roles. We also explore whether this new dynamism in the Mediterranean ports is reversing the long-standing hinterland domination of the ports of the northern range. We demonstrate that the gateway ports of the western Mediterranean continue to serve local and regional markets, with very limited penetration north of the Alps and Pyrenees. This is due in part to difficulties with rail services but also because of the continued efficiency of the northern range ports and their hinterland connections. We suggest that in the short run, at least, little change is likely.  相似文献   
3.
Qualitative upgrading of the educational process at university level marine education depends largely on the instructive value of the trainers’ educational software. Marine education software has developed out of a certain initial implementation in an equivalent manner to which the programs of practice and training have been applied in cases of simulations and programming environments. In most cases, educational software categories have developed without taking into consideration any special pedagogical theory.  相似文献   
4.
This article deals with macroscopic traffic modeling and online parameter estimation suitable for real-time simulation of complex road configurations. A numerical model for the nonlinear hyperbolic transport equation is introduced that works with a fundamental diagram of arbitrary shape and piecewise differentiable, discontinuous initial conditions. Suitable boundary conditions at road inlets and outlets are realized. A method to identify parameters of the underlying fundamental diagram via aggregated traffic sensor data is presented and the Fisher Information Matrix is utilized to optimize traffic sensor placement. The choice of parameterization, sensor placement, and the range of sensor data affect identifiability of the parameters of the fundamental diagram. The results are validated by comparison with a microscopic traffic simulation based on a car-following model.  相似文献   
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This paper presents Prototype Système 2 Global (PSY2G), the first Mercator global Ocean General Circulation Model (OGCM) to assimilate along-track sea level anomaly (SLA) satellite data. Based on a coarse resolution ocean model, this system was developed mainly for climatic purposes and will provide, for example, initial oceanic states for coupled ocean-atmosphere seasonal predictions. It has been operational since 3 September 2003 and produces an analysis and a two-week forecast for the global ocean every week. The PSY2G system uses an incremental assimilation scheme based on the Cooper and Haines [Cooper, M., Haines, K., 1996. Data assimilation with water property conservation. J. Geophys. Res., 101, 1059-1077.] lifting–lowering of isopycnals. The SLA increment is obtained using an optimal interpolation method then the correction is partitioned into baroclinic and barotropic contributions. The baroclinic ocean state correction consists of temperature, salinity and geostrophic velocity increments and the barotropic correction is a barotropic velocity increment. A reanalysis (1993–2003) was carried out that enabled the PSY2G system to perform its first operational cycle. All available SLA data sets (TOPEX/Poséïdon, ERS2, Geosat-Follow-On, Jason1 and Envisat) were assimilated for the 1993–2003 period. The major objective of this study is to assess the reanalysis from both an assimilation and a thermodynamic point of view in order to evaluate its realism, especially in the tropical band which is a key region for climatic studies. Although the system is also able to deliver forecasts, we have mainly focused on analysis. These results are useful because they give an a priori estimation of the qualities and capabilities of the operational ocean analysis system that has been implemented. In particular, the reanalysis identifies some regional biases in sea level variability such as near the Antarctic Circumpolar Current, in the eastern Equatorial Pacific and in the Norwegian Sea (generally less than 1 cm) with a small seasonal cycle. This is attributed to changes in mean circulation and vertical stratification caused by the assimilation methodology. But the model's low resolution, inaccurate physical parameterisations (especially for ocean–ice interactions) and surface atmospheric forcing also contribute to the occurrence of the SLA biases. A detailed analysis of the thermohaline structure of the ocean reveals that the isopycnal lifting–lowering tends to diffuse vertically the main thermocline. The impact on temperature is that the surface layer (0–200 m) becomes cooler whereas in deeper waters (from 500 to 1500 m), the ocean becomes slightly warmer. This is particularly true in the tropics, between 30°N and 30°S. However it can be demonstrated that the assimilation improves the variability in both surface currents and sub-surface temperature in the Equatorial Pacific Ocean.  相似文献   
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