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11.
Abstract

This is an exploration of the political economy of ports in the United States and Great Britain. A number of technical, economic, and political issues concerning ports are examined. Particular attention is paid to the institutional evolution of ports from private to public ownership, and its consequences for port efficiency. The paper concludes with a set of recommendations designed to reverse the trend toward port nationalization in both countries.  相似文献   
12.
Abstract

This article outlines the steps that have been taken to conserve the coast of Great Britain. It treats the subject historically and emphasizes the ways in which unofficial and official bodies have interacted. Apart from a few very restricted areas, the shoreline is open to all people. The siting of houses, chalets, and huts is strictly controlled. Problems arise from time to time as to the location of nuclear stations, oil storage areas, and similar installations; these issues are settled in full discussions at official inquiries at which all interests—official, business, and conservation–are represented.  相似文献   
13.
The Oder River estuary is a large and complex system composed of lagoons, lakes and river branches in which numerous biogeochemical processes lead to modification of loads of dissolved/suspended material brought in with the riverine waters. Budget calculations show that on an annual basis, 71–88% of total nitrogen, 73–89% of total phosphorus and 72–101% of BOD5 inflowing to the estuary are exported to the Baltic Sea. Among the inorganic nutrient species, nitrates exhibit the highest net transformation rate into organically bound forms (over 60%). The transformation could have been equally high or even higher in the case of ammonia and phosphates but these processes may have been compensated by intensive mineralization. The mechanisms responsible for the nutrient transformation patterns, as well as their net effect on the annual loads delivered into the Baltic Sea, are discussed in the paper. Phosphorus seemed to play a limiting role in phytoplankton production in the estuary in spring, while nitrogen did the same in summer.  相似文献   
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15.
In this paper an introduction to the principles and methods used in logistics and supply chain management is presented. It begins by a discussion on fundamentals and explains the relevant terms. Next policy and practice associated with logistics and freight services are regarded with a focus on the EU policy for the sector which greatly influences the development of logistics chains and services. Mathematical formulation of typical transport and logistics-related problems is also presented followed by a discussion on the concept of sustainability.  相似文献   
16.
未来严格的排放法规及低成本要求,推动了催化转化技术的发展。目前,特殊结构薄板金属载体的使用和先进的涂层技术正在被研究,目的是提高催化转化器的转化效率。通过对标准型、冲孔型(PE)和纵向结构(LS)载体与不同涂层技术、助催化存储材料、涂层和贵金属(PGM)含量的讨论得出,紊流结构载体的热起动性能优越,而且在废气流量较大的试验工况下转化效率较高。  相似文献   
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18.
The article describes the application of a 1:5-scaled roller rig with a two-axled experimental vehicle to the design of a torque-controlled railway wheelset. Particular attention is drawn to the scaling problem and the dynamic similarity laws behind it and in addition to the chosen scaling strategy. For the controller design of the active wheelset the experiments with the scaled vehicle were combined with multibody computer simulations. The complete mechatronic system has therefore been modelled using the SIMPACK-MATLAB/Simulink interface. The steering behaviour, typical for this particular active wheelset, is demonstrated by results from roller rig experiments.  相似文献   
19.
金属载体催化转化器在摩托车上的应用   总被引:1,自引:0,他引:1  
1 德国依米泰克公司介绍 随着世界范围内机动车排放法规的日益严格,对车用催化转化器的要求也越来越高。由于金属材料在物理特性上具有许多优点,金属载体对催化转化率及发动机动力性能、经济性能都具有积极影响,具有广阔的发展前景。1986年德国西门子公司汽车部与GKN公司各出资50%成立了依米泰克(Emitec)公司,专业生产车用催化转化器金属载体。  相似文献   
20.
This paper examines the impact of containerization on upstream urban ports in Europe, briefly discusses the changing socio-economic role of such ports,and considers whether the few remaining upstream urban ports currently still attracting large containerships can continue to do so in the long-term. Citing the trend towards larger containerships, the analysis concludes by offering the view that continued investment in container-handling infrastructure within traditional upstream urban ports may be a flawed policy. Such ports are becoming outmoded (for the largest containerships), superseded by more appropriate custom-built infrastructure at coastal locations.  相似文献   
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