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21.
Environmental issues have received a prominent place in transport policies of most European countries. The coordination of such policies however, is fraught with many difficulties. The increasing freight flows after the European integration are a source of concern, but have not yet led to straightforward and effective environmental strategies.The paper focuses on the Trans Alpine freight transport systems in the light of the future integration of single national transport systems into the European transport network. The environmental, social and institutional peculiarities of this ‘region’ have favoured—in the past—the development of strong nationally-oriented policies, partly in contrast with the goals promoted by the European Union. The present analysis aims to highlight opportunities, and limits inherent, in the implementation of various infrastructure projects oriented towards a drastic change of the Alpine transport systems structure. The Alpine countries, viz. Austria and Switzerland, play a central role in the promotion of environmental benign modes of transport of goods, with a clear focus on rail. The route choice and modal split of freight flows in Europe are taking place simultaneously. In this paper the results of European freight flow models (based on logit analysis and neural networks) will be presented. An important exercise is then to assess the consequences of various types of eco-taxes on road transport in Europe. In this context, several policy scenarios will be dealt with.  相似文献   
22.
This paper presents a case study which tackles a general problem for railway management, namely the formulation of a strategy to improve business financial performance. This is prefaced, in Section 2, by discussion of general principles - concerning the type of information system required, investigations to be conducted and associated measurement needs. The case study, of Section 3, concerns our investigations of VicRail's total business and its constituents. The task of financial improvement is revealed from an assessment of sectors' current cost-recovery positions and the identification of system joint costs. For freight sectors, future traffic prospects, pricing possibilities and the scope for more efficient operations are then considered, and the implications traced for overall deficit reduction and the development of business strategy. The concluding section draws some general lessons for railway managements.A fuller discussion by the authors of the theoretical framework employed, and particularly of the case study application, is contained in a complimentary publication: Improving Railway Financial Performance, published by Gower in January 1985.Transmark is a subsidiary of the British Railways Board, acting as its international consultancy. The authors, who were respectively study director and manager, wish to thank Bernard Warner (an independent consultant), Richard Eccles (of Transmark) and Adrian Balkyn-Rackowe (of British Rail) for their valuable contributions. The study report, titled Rail Cost — Pricing Options, was released by the Minister in April 1981.  相似文献   
23.
The paper describes the results of a pilot survey that used a one-day activity diary to collect origin-destination data, as opposed to a travel-based diary. The design of the diary is discussed, together with a comparison to a more conventional travel diary. The paper examines the extent to which the activity diary appears to have been capable of collecting good travel data that is at least comparable to travel diary efforts. In addition, a substantial portion of the paper is concerned with a comparison of the retrieval methods for the diaries. Two alternative methods were pilot-tested, one being the use of telephone retrieval and the other being mailback retrieval. Although the pilot test used small samples, the evidence appears to be strong that mailback is preferable to telephone retrieval, while telephone retrieval did not seem capable of providing some of the benefits often ascribed to it.  相似文献   
24.
Peter 《世界汽车》2007,(1):38-41
田在美国全面改进了7座高级SUVAcuraMDX。第二代AcuraMDX配备最大输出功率为223kW(6000r/rain)的V型6缸发动机.以及可以带4轮驱动力控制的”SHAWD《SuperHandlingAll-WheeDrive)”。该车的发动机在美国市场是输出功率最高的自然吸气V6发动机。  相似文献   
25.
ABSTRACT

This paper describes a method to analyse and evaluate different trajectory planning methods and controller types for usage in automated vehicles. Its application is shown by using a novel trajectory planning approach considering comfort aspects (based on Rapidly Exploring Random Tree (RRT)), two different controllers to follow the planned path (cascade controller and flatness based controller) and a simulation method to obtain resulting lateral vehicle accelerations. The method is used to plan and drive a trajectory through a roundabout. It can be seen that the lateral accelerations of the controller-driven vehicle are in the range of the values used for planning. However, the results of both controllers show differences in lateral deviation and in smoothness of lateral accelerations. The simulation results are then compared to real-world test drives in the same roundabout. The measured lateral accelerations are in the same range as well but show a smoother progression than the two controller models.  相似文献   
26.
尽管癌症治疗在过去的十多年取得了显著进展,但肿瘤学仍属于目前最不能满足临床需要的学科领域。在过去十多年里,临床药理学的进步和研发活动方面的巨大投资使得“癌症治疗”发展为“治疗过程研究”的数量急剧增加。但事实上,癌症和其他慢性疾病一样,治疗效果都很差,由此很多大型医药公司和生物制药公司都比以往更大力度的投入资金,用于肿瘤学和其他强效候选药物的研发上。[第一段]  相似文献   
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28.
关于铁路隧道内安全的新UIC规程适用于新建和既有隧道。该规程制定了可靠的基础设施、车辆和运输调度措施来提高隧道内的安全性,尤其注意了隧道内的防火问题。  相似文献   
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黄炜炳 《汽车杂志》2010,(1):270-270
前段时间和国内几家权威IT媒体主编交流,他们无一例外地抱怨现在导航厂商都不投放广告,令网站的内容更新与生存倍感压力。  相似文献   
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