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91.
拆船业的发展对国家尤其是发展中国家经济发展起到重要的影响作用。本文从分析全球拆船市场、我国拆船市场入手,对我国拆船业的发展从政府及企业层面提出了相关建议。 相似文献
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本文在总结CAPP各单元技术发展状况和其他有关的计算机技术发展状况的基础上,结合CAPP系统各周边环境目前的发展状况,在对CIMS背景下如何考虑CAPP系统的体系结构问题进行了详细的论述,对若干难于处理的技术关键提出了的对策。 相似文献
95.
王志恩 《西安交通大学学报(英文版)》1995,(2)
T_H1ANDT_H2CELLANTIGENRECEPTORSINEXPERIMENTALLEISHMANIASISStevenL.Reiner,WangZhi'en;FarahHatam,PhillipScott,RichardM.Locksley(... 相似文献
96.
The work described was undertaken as part of the CASSIOPE project in the EC DRIVE programme. A range of fare collection procedures in public transport is described, and the importance of these for data collection by operators is stressed. It is suggested that such data management could be standardized and to this end four case studies were carried out in different European cities. Data models were built for each city, and these models are merged into a preliminary version of a generalized model. The need and uses for such a fare collection data model is explained. 相似文献
97.
Alan W. Williams 《Transportation》1995,22(2):115-134
The paper puts the case that historical analysis helps to understand current discussions on user-pays principles and practice. In particular, (a) it is demonstrated that the nature of funding systems is dominated by political considerations, and (b) user-pays systems lead to inadequate funding of infrastructure when politically controlled, but provide funds for expansion when “market-driven” (in pursuit of profit maximisation). The case is illustrated by reference to the experience of interregional transport infrastructure in 19th century in England and 20th century Australia. Revenue deficiencies arising from government-controlled rates can lead to the demise of private transport infrastructure. The problem is considered in the context of the history of interregional roads and railways in England between the 15th and 19th century in England and in Australia in the 19th and 20th century. The current embrace by government of the user-pays system in transport services arises from fiscal deficiencies, as much from economic philosophy. User-pays policies are part of the global re-emergence of economic rationalism since the 1970s. The lesson for other nations from Australia's experience is twofold. First, in a federal system of government, despite the efficiency benefits of user-pays in interregional land transport, fiscal and political objectives will prevail. Second, in sparsely populated and/or developing countries, deregulation of long distance road transport will make funding a national highway system a critical concern. 相似文献
98.
D. R. Glen 《Maritime Policy and Management》1997,24(3):245-260
This paper examines the dynamic behaviour of second-hand prices of tankers and dry-cargo vessels over various time periods, with a view to determining whether or not the markets for such assets are efficient. It extends and re-analyses the results of an earlier study by Hale and Vanags, published in this journal in 1992. Using a more modern method of testing for cointegration, it is shown that both the tanker and dry cargo markets appear to be cointegrated, a fact which would suggest that these markets are inefficient. It is suggested that the existence of cointegration does not necessarily imply market inefficiency, if the factors that create the common trends are themselves stochastic in nature. With this in mind, it is argued that the evidence put forward in this paper is still consistent with market efficiency in the long run. 相似文献
99.
G.I. Bogomaz O.M. Markova Yu.G. Chernomashentseva 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1998,30(3):285-294
Dynamics and loading of railway tank cars transporting liquid cargo are investigated. The approach based on the mechanical-pendulum analogy for the liquid cargo mobility simulation is proposed. Hydrodynamic parameters of the mechanical analogy are determined using the solution of the boundary-value problem for the liquid cargo vibrations in a cavity with the tank boiler shape. The fitting of the developed mathematical models is proved by comparison of calculated results and test data. Vibration characteristics and loading of tank-cars under their shunt collisions and motion along straight and curved track in trains are evaluated. It is shown that as a rule the liquid cargo mobility has an essential influence on tank dynamic properties. 相似文献
100.