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51.
为了解决煤码头堆场煤尘问题,唐山港曹妃甸港区某煤码头堆场采用封闭大棚,项目建成投入使用后,产生了很好的抑制煤尘外溢的环保效果.封闭大棚建设方案可适用于通用码头煤堆场和专业化码头堆场,有效替代现阶段的防风网抑尘设施,控制粉尘污染效果明显,能极大改善和保护环境,环保效益特别显著,可使企业每年免缴大额排污费.  相似文献   
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Abstract

The passage of the Marine Plastics Pollution Research and Control Act of 1987 (MPPRCA), which codified Annex V of the International Convention for the Prevention of Pollution from Ships (MARPOL), has encompassed every commercial and recreational shipping and boating facility in the United States. As a group, these ports, harbors, and marinas form a significant, although proportionately small, portion of the coastline of the country. More important, the economic benefits derived from the complex shoreside infrastructures required for international ocean trade, commercial and recreational fishing, and pleasure boating indicate just how critical it is for these facilities to be in conformance with effective and prudent coastal zone and environmental management practices.  相似文献   
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This paper considers the development of a method for network vulnerability analysis which considers the socio-economic impacts of network degradation and seeks to determine the most critical locations in the network. The method compares the levels of remoteness (or its inverse, accessibility) of localities within the study region, on the basis of the impacts of degradation of the road network on a recognised accessibility/remoteness index that can be applied to each and every location within the region. It thus extends the earlier work on accessibility-based vulnerability analysis which was limited to assessment of impacts on selected nodes in a network. The new method allows study of impacts on both specified locations (which do not have to be represented as network nodes) and the region as a whole. The accessibility/remoteness index is defined so that an accessibility surface can be calculated for the region, and the volume under this surface provides an overall measure of accessibility. Changes in the volume under different network states thus reflect the overall impacts. The method is applied to a rural region in south east Australia.  相似文献   
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A key concern in managing vehicle routing operations under stochastic demands is whether, on the basis of travel distance, route modification yields materially greater logistical efficiency than fixed routes. This research uses statistical calibration as the primary technique to develop a robust and tractable model for estimating this difference in logistical efficiency. Based on features such as the models predictive accuracy and generalizability, it constitutes a substantive improvement over existing models. The present study also expands the range of predictive models relevant to vehicle routing under stochastic demands with models to estimate the transportation and inventory effects of persuading customers to stabilize their ordering patterns.  相似文献   
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堤路结合在泉州金塔防洪堤的应用   总被引:1,自引:0,他引:1  
以泉州金塔段堤路结合工程设计为实例,充分分析了堤、路所涉及的水利、市政两个行业的设计规范,选择合适的设计指标,在平面布置、路基和交叉建筑物等方面实现了堤路有机结合。  相似文献   
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The transport demand in most major cities around the world can only be met with a high‐quality public transport system. The requirements on bus, rail, underground and tram systems are manifold with reliability and efficiency as the key factors. The service operating hours and the size of the network are often extended in order to serve the needs better. Further, most metropolitan areas are trying to provide more incentives for citizens to leave the car at home and use the local transit systems instead. The reasons are well known. Not only does a public transport system only make economical sense if it is well used, but most urban areas with a high car‐dependency face at least three major problems; safety, congestion, and pollution (noise and air pollution, land separation, etc.). It is generally recognised that to decrease car usage and to increase public transport usage a stick & carrot approach is needed. The London congestion‐charging scheme is an example since all revenues collected by the scheme are put into the improvement of bus and underground services.  相似文献   
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液货舱透气系统设计与计算方法研究   总被引:1,自引:1,他引:0  
针对IMO通涵以及ISO标准的新要求,从船东、船厂和船舶设计院所履行职责的角度,对新建油船和化学品船透气系统的设计与计算方法进行研究,并给出了实例。  相似文献   
60.
与2009年最后一场大型车展——法兰克福车展(IAA2009)给人的印象一样,上月结束的北美国际车展(NAIAS2010)继承了上一届的“绿色”主题,为观众呈现了一场电动车与混合动力车的视觉盛宴。可见,全球的汽车制造商都正迅速有序地按计划推出新车来应对来自市场因调整而产生的巨大挑战。  相似文献   
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