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141.
Transportation policy in America distinguishes between capital expenditures and recurrent operating and maintenance costs. Federal policy and resources encourage capital-intensive projects, but traditionally have left to state and local governments the responsibility for maintaining and operating the facilities built with federal support. This has led to consistent underestimation of operating costs in the decision process leading to capital expenditures, and to overcapitalization of transportation networks. Today, faced with recurrent costs which strain local resources, there is pressure to broaden federal participation in operations and maintenance, and legislation is beginning to weaken the traditional distinctions between capital and recurrent expenditures.  相似文献   
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1阿尔卑斯山通道概况 瑞士位于欧洲联盟南北部之间,自1980年以来,南北部繁忙的交通运输使瑞士的运量提高了十几倍。为了减轻交通运输压力,保护阿尔卑斯山及其周围环境,瑞士修建了从南到北贯穿全境的铁路大动脉——阿尔卑斯山通道。针对阿尔卑斯山通道隧道群的施工安全与人员健康方面的经验和教训,进行了全面总结,  相似文献   
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汽车部件对污染的敏感性   总被引:1,自引:0,他引:1  
污染敏感性分析是实现对整个机械系统污染控制的重要步骤。通过对污染的分析、测试、建模及模拟分析可有助于减少污染物或微小颗粒对机械系统造成的污染,避免因污染而导致的系统故障。对有关汽车机械系统污染的问题进行了分类讨论并进行了相关性分析,对测试及计算机建模方法进行了论述。给出了污染敏感性分析流程,最后通过几个典型实例阐明了污染敏感性分析的意义。  相似文献   
145.
This article presents an approach that couples coastal ecosystem modeling with integrated environmental assessment methodologies to support coastal management. The focus is to support the development of an ecosystem approach to aquaculture management including interactions with watershed substance loading. A Chinese bay, with intense aquaculture and multiple catchment uses, and where significant modeling efforts were undertaken is used as a case study. The ecosystem model developed for this bay is used to run scenarios that test the local management strategy for nutrient reduction. The corresponding ecological and economic impacts of the managers’ scenarios are analyzed by means of the Differential Drivers-Pressure-State-Impact-Response (ΔDPSIR) analysis. Emphasis is given to the analysis of the eutrophication process in the bay including present eutrophic condition and the expected changes due to the simulated scenarios. For this purpose, the Assessment of Estuarine Trophic Status (ASSETS) screening model is a valuable tool to interpret and classify the data and model outputs regarding eutrophication condition and to evaluate the manageable level of the nutrient loading entering in the bay.  相似文献   
146.
The container terminal community   总被引:1,自引:0,他引:1  
Over the past 30 years, technological developments have not only affected the design and operation of the port function, but also the organizational and institutional relationships within the port community. Two inter-organizational interaction models are presented, drawing on the findings of over 200 in-depth interviews with senior managers representing terminal operators, shipping lines, feeder operators, ship agents, road hauliers, freight forwarders and shippers serving the UK?Far East trade. The first model represents a breakbulk berth of the 1960s and the second a modern container terminal community. In comparing the models, it is shown that containerization has transformed the fragmented breakbulk operation of the 1960s into the cohesive container terminal community that today facilitates port operations. The paper concludes by examining trends in key inter-organizational relationships in the community and the emergence of eBusiness.  相似文献   
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