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Future climate change is expected to affect inland waterway transport in most main natural waterways in Europe. For the river Rhine it is expected that, in summer, more and longer periods with low water levels will occur. In periods of low water levels inland waterway vessels have to reduce their load factors and, as a result, transport prices per tonne will increase. One possible consequence of these higher transport prices is a deterioration of the competitive position of inland waterway transport compared with rail and road transport, and thus a change in modal split. We study this issue using a GIS-based software model called NODUS which provides a tool for the detailed analysis of freight transportation over extensive multimodal networks. We assess the effect of low water levels on the costs of transport operations for inland waterway transport in North West Europe under several climate scenarios. It turns out, that the effect on the modal split is limited. Under the most extreme climate scenario, inland waterway transport would lose about 5.4% of the quantity that is currently being transported annually in the part of the European inland waterway transport market considered. The very dry year of 2003 can be seen as an analogue for this scenario.  相似文献   
2.
Some organisms that live just below the sea surface (the neuston) are known more as a matter of curiosity than as critical players in biogeochemical cycles. The hypothesis of this work is that their existence implies that they receive some food from an upward flux of organic matter. The behaviour of these organisms and of the associated organic matter, hereafter mentioned as floating biogenic material (FBM) is explored using a global physical–biogeochemical coupled model, in which its generation is fixed to 1% of primary production, and decay rate is of the order of 1 month. The model shows that the distribution of FBM should depart rapidly from that of primary production, and be more sensitive to circulation patterns than to the distribution of primary production. It is trapped in convergence areas, where it reaches concentrations larger by a factor 10 than in divergences, thus enhancing and inverting the contrast between high and low primary productivity areas. Attention is called on the need to better understand the biogeochemical processes in the first meter of the ocean, as they may impact the distribution of food for fishes, as well as the conditions for air–sea exchange and for the interpretation of sea color.  相似文献   
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1简介 在汽车制造过程中,作为一种金属连接的方式,结构粘合剂的应用正处于迅猛发展阶段。结构粘合剂可增强粘接结构的刚性、耐久性和抗冲撞性。此外.该粘合剂的使用使得相容性差的金属之间的粘接变得容易,因此从成本高低和车体质量大小方面加大了车体结构优化设计的可能性。  相似文献   
4.
It is essential that transport infrastructures are protected against events which cause their failure. At an optimal level of protection, the sum of protection costs and expected residual damages following from disruptions will be minimized. In most cases however, this optimal level is not achieved because infrastructure protection is susceptible to various market and government failures. This brings us to the question who (a private or public actor) should do how much (the level of protection and intervention). This question is addressed in the present paper.

The starting point of the paper is the Directive of the European Council on the identification and designation of European Critical Infrastructures. We review the protection of critical waterborne transport infrastructures from an economic perspective. The review is based on a literature study and several interviews with Critical Infrastructure experts. For the studied infrastructures, we have identified causes and effects of their failure and examined the private–public roles in protecting them. Considering the market and government failures which occur in such configuration of roles, we propose several changes. We conclude that from a national policy perspective there are two important routes: (1) reinforcement of private sector roles among others by defining liabilities and providing information on risks and (2) strengthening of supra-national collaboration via improving and standardizing regulations, cost-sharing initiatives and penalty systems.  相似文献   
5.
From 2018, Autonomous Emergency Braking (AEB) systems dedicated to avoid or mitigate passenger car-tocyclist collisions will be considered in the safety assessment by Euro NCAP. To test such systems, appropriate equipment has been developed in a project called CATS “Cyclist-AEB Testing System”, that has run between April 2014 and August 2016. Moreover, a proposal for the most relevant test scenarios was set up. The objective of the project was to provide proof to Euro NCAP of the relevance of the proposed test scenarios and of the feasibility of practical implementation of the scenarios and test setup. The process regarding the selection, verification and validation of test scenarios is described. The cooperation between 17 industrial partners (car manufacturers and automotive suppliers) in the CATS project has stimulated the harmonization and acceptance of the protocol, target and test setup. The process and intermediate results including the used methodology, have been reviewed by the German Federal Highway Research Institute (BASt) and have been shared on a regular basis during the project with stakeholders in Europe, Japan and the USA. Euro NCAP already indicated to consider the results of the CATS project as the main input to draft the test protocol, including scenarios and target for Cyclist-AEB systems in 2018 and 2020.  相似文献   
6.
This paper presents a new method for the design and validation of advanced driver assistance systems (ADASs). With vehicle hardware-in-the-loop (VEHIL) simulations, the development process, and more specifically the validation phase, of intelligent vehicles is carried out safer, cheaper, and is more manageable. In the VEHIL laboratory, a full-scale ADAS-equipped vehicle is set up in a hardware-in-the-loop simulation environment, where a chassis dynamometer is used to emulate the road interaction and robot vehicles to represent other traffic. In this controlled environment, the performance and dependability of an ADAS is tested to great accuracy and reliability. The working principle and the added value of VEHIL are demonstrated with test results of an adaptive cruise control and a forward collision warning system. On the basis of the 'V' diagram, the position of VEHIL in the development process of ADASs is illustrated.  相似文献   
7.
Transportation - The Netherlands seems to exhibit the unique conditions that allow cycling on the country level instead of only the city level. Moreover, the national transit system seemingly...  相似文献   
8.
结构胶粘剂是汽车制造过程中一种日趋重要的金属连接方式。文章介绍了汉高公司开发的一种汽车用结构胶粘剂的性能特点及应用工艺要求,并通过实验证明结构粘合剂对于提高车体结构性能、减轻车体质量、简化生产过程和优化生产成本来说,是一种十分有用的材料。  相似文献   
9.
Hydrodynamic impacts of free surface waves are a widely known issue in coastal and ship engineering. They can result in severe damage to important industry facilities (e.g. offshore wind turbines) or means of transport (e.g. oil tankers). This kinds of damage give rise to different difficulties due to economic losses and environmental pollution. On that account, the present paper deals with a special feature of a protective mechanism for offshore structures. We develop a numerical multiregional wave-structure impact model of a damping element prototype. The investigated prototype consists essentially of an elastic cover that is attached to the cylindrical mono-pile foundation at wave level. The chamber between the flexible structure and the mono-pile is filled with a liquid. A prototype of the damping element has been constructed as a mono-pile structure test object. In order to measure the hydrodynamic loads on the test object, we placed piezoelectric sensors on the stagnation points of the mono-pile. The multiregional simulation model created is able to imitate the wave impact and its consequences. These implications include the deformation and oscillation of the elastic shell, the resultant force affecting the pile and the dissipation power of the damping fluid. The dissipation power can be understood as the crucial factor preventing the shell from oscillating over long periods of time. It enables us to state the mechanical energy that is transfered due to the wave’s impact on the damping fluid region.  相似文献   
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