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971.
在分析并行工程特点的基础上,提出了并行工程下的船舶设计建造系统结构,讨论了其实现的关键技术.给出基于DFM/DFA的CAD/CAM/CAE集成示例. 相似文献
972.
《技规》第285条规定:凡进站、接车进路信号机不能使用,或在双线区段由反方向开来列车而无进站信号机时,应使用引导信号或派引导人员接车。引导接车时,列车以不超过20 km/h速度进站,并做好随时停车的准备。
1 问题描述 相似文献
973.
Carlos F. Daganzo 《Transportation Research Part B: Methodological》1980,14(3):229-239
This paper complements the preceding one, which showed how one could modify equilibrium traffic assignment algorithms for networks with many centroids. In this one it is shown how one can substitute centroids by zones with continuous population densities. The technique, which is mathematically guaranteed to approximate a flow pattern in accordance with Wardrop's user equilibrium criterion, requires some geometrical calculations which can be handled off-line. With the suggested approach, it is possible to represent the spatial distribution of trip ends more realistically and this allows traffic assignment models to capture the effects of short and intrazonal trips in a way previously impossible. The method is shown to be computationally feasible. 相似文献
974.
十年前,中国船级社(CCS)紧紧把握船检体制变革带来的发展机遇和发展动力,站在服务国家相关行业发展的全局高度,重视战略思考和战略布局,以前瞻性的目光及时捕捉全球航运安全要求不断提升、船舶大型化和技术附加值提升、我国造船产能快速提升、我国自有船队不断发展等趋势,通过"局社分开"后的前期转型,有力地促进了跨越发展。今天,围绕落实中央关于加快转变经济方式的战略部署以及全国交通运输工作会议的要求,2月27日,CCS总裁李科浚在2010年工作会议上,对CCS加快转型发展作出了详细部署,再次拉开了转型发展的大幕。 相似文献
975.
Timon H. Stasko H. Oliver Gao 《Transportation Research Part D: Transport and Environment》2010,15(5):254-262
Bus transit is often promoted as a green form of transportation, but surprisingly little research has been done on how to run transit systems in a green manner. Both vehicle task assignment and purchase models are generally constructed to minimize financial costs. Integrating vehicle task assignment with purchase decisions is made challenging by the different time scales involved. An integer programming approach is used to combine vehicle purchase, retrofit and aggregated task assignment decisions. The formulation is designed to operate in sequence with traditional vehicle task assignment models, to add emissions and long term financial cost elements to the objective, while maintaining computational tractability and feasible input data requirements. In a case study, a transit agency saves money in the long term by using stimulus money to buy CNG infrastructure instead of purchasing only new buses. Carbon prices up to $400/(ton CO2 equivalent) do not change vehicle purchase decisions, but higher carbon prices can cause more diesel hybrid purchases, at a high marginal cost. Although the motivation and numerical case study are from the US transit industry, the model is formulated to be widely applicable to green fleet management in multiple contexts. 相似文献
976.
Much has been said of the importance of port and terminal integration in the supply chain. Authors have stressed the importance of agility to the port environment, which involves being proactive along supply chains, facilitation of intermodal integration, as well as organizational integration and partnership between ports and users. Despite the well articulated importance of the issues, little has been offered in terms of conceptualizations and empirical evidence of what really is meant by port/terminal integration in the supply chain, how such integration can be measured and quantified as well as the extent to which different ports/terminals in the world are integrated in the supply chain and competitive performance implications arising thereof. This paper aims to make a contribution in this respect by (i) reviewing the relevant literature on supply chain integration and port integration in the supply chain, (ii) conceptualizing measures for port/terminal integration in the supply chain, (iii) empirically testing the influence of port/terminal integration in the supply chain on port competitiveness and (iv) outlining the significance and value of the study for port operators, shipping lines, transport providers and for further research. 相似文献
977.
978.
上海航运交易所信息部 《集装箱化》2009,20(5):40-40
本期我国出口集装箱运输需求颓势明显,3大航线货量均欲振乏力,但在多条航线2009年4月1日提价的拉动下,上海航运交易所发布的中国出口集装箱综合运价指数先抑后扬。2009年4月17日。上海航运交易所发布的中国出口集装箱运价指数报833.92点,上海地区出口集装箱运价指数报800.66点.均与上月同期基本持平。 相似文献
979.
Joanne Ellis Björn Forsman Susann Gehl Uwe Langbecker Kurt Riedel Pierre C. Sames 《WMU Journal of Maritime Affairs》2008,7(1):133-149
Commercial shipping of containerized goods involves certain risks for human safety and environment. In order to actively manage these risks, they must be identified, analyzed, modeled, and quantified. This requires a systematical analysis of design and operation of container vessels. Within the EU-funded research project SAFEDOR, a Formal Safety Assessment has been applied to establish the current safety level of generic container ships and to identify potential cost-effective risk control options. This paper describes a structured approach to develop the underlying high-level risk model. It is structured as risk contribution tree consisting of a series of fault trees and event trees for the major accident categories. Statistical analysis of casualty data is used to estimate the probability of occurrence. Finally, the summation overall individual risk contributions yields the current risk pro file for the operation of container vessels is presented as FN-curve. 相似文献
980.
首先以亲身经历叙述了江南造船史上的一些往事,这些事体现了"自强不息,打造一流"的江南精神.接着论述了船舶工业在海军建设、航运发展与海洋资源开发中的重要作用.当人类进入海洋时代之际,作为世界人口众多的社会主义海洋大国的中国必须拥有强大的海上力量,船舶工业具有广阔的发展前景.文章从生产效率、物资和能源消耗、专业化生产诸方面探讨了我国船舶工业和世界先进造船业的差距.作者认为当前的首要任务是充分发挥江南精神,培养一支具有高度责任感、使命感、进取心和主人翁精神的工人阶级队伍,为把我国建成为世界造船大国和强国做出更多贡献. 相似文献