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501.
孙连成 《水道港口》2008,29(1):8-15
基于天津港近些年来重大工程项目的建设,利用物理模型、数学模型及现场实测资料分析等科研手段,对天津港深水航道的建设、南疆港区的扩建、南北防波堤的延伸及东疆港区海岸一期工程的建设,进行了一系列的试验研究。(1)天津港海域开挖建设深水航道从自然条件方面是可行的;(2)海河口北治导线南移,使两治导线间距由1900 m缩为1200 m。既能满足泄洪要求,又能扩大南疆的用地面积;(3)防波堤延伸至16+0,港内的流态及泊稳均能满足设计要求,可使天津港减少60%的淤积量;(4)试验结果对东疆港区东海岸一期工程人工沙滩的冲淤稳定性、港内的水体交换等,提出了优化措施。  相似文献   
502.
面对市场激励的竞争,提出上海外贸集装箱装卸价格策略应定位在以竞争为主的价格策略,叙述了几种不同的价格调整策略,最后介绍了要实施所制定价格调整策略,所必需的保障措施。  相似文献   
503.
Using a game theory approach, this paper analyses a situation in which the government imposes a certain emission tax on vessels and port operations for emission control in port areas. Two ports are considered: a purely private port and a landlord (partial public) port. These two ports are in Cournot or Bertrand competition or cooperation with differentiated service. Our model outcomes lead to the following conclusions. First, the optimal private level of port 2 under Cournot and Bertrand competitions varies between fully private and highly public concerned port, while government will prefer a highly public concerned or close to highly public concerned port in the cooperation scenario. Second, government will have to make more and stricter efforts to enhance environmental protection in the situation of port cooperation (monopoly) than in the case of inter-port competition, and all the optimal emission tax should be always lower than the marginal emission damage. Third, port privatization has a non-monotonous effect on ports’ environmental damage in the inter-port competition scenarios and a monotonous decreasing effect in the cooperation scenario. Fourth, the total emission tax revenue is always higher than the overall environmental damage in the cooperative scenario, and it may or may not be able to cover the whole environment damage in Cournot and Bertrand competitions. Finally, the government may face a trade-off among environmental protection, maximizing social welfare, satisfying individual motivation, when considering port cooperation (monopoly).  相似文献   
504.
According to a range of assessments, there exists a large cost-effective potential to increase energy efficiency in shipping through reduced speed at sea enabled by shorter time in port. This means that the energy needed can be reduced whilst maintaining the same transport service. However, the fact that a large cost-effective potential has been identified that is not being harnessed by decision-makers in practice suggests that there is more to this potential to understand. In this paper, the possibilities for increasing energy efficiency by reducing waiting time in port are explored and problematised through a case study of a short sea bulk shipping company transporting dry bulk goods mainly in the North and Baltic seas. Operational data from two ships in the company’s fleet for one year showed that the ships spent more than 40% of their time in ports and that half of the time in port was not productive. The two most important reasons for the large share of unproductive time were that ports were closed on nights and weekends and that ships arrived too early before the stevedores were ready to load or unload the cargo. Reducing all of the unproductive time may be difficult, but the results also show that even a conservative estimate of one to four hours of reduced time per port call would lead to a reduction in energy use of 2–8%. From in-depth interviews with employees of the shipping company, ports and ship agencies, a complex picture is painted when attempting to understand how this potential arises. Aspects such as a lack of effective ship-shore-port communication, little time for ship operators, an absence of means for accurately predicting energy use of voyages as a function of speed, perceived risk of arriving too late, and relationships with third-party technical management may all play a role.  相似文献   
505.
There are many studies on container port efficiency and that seek to understand what factors, such as technical and scale efficiency, private versus public terminal management or macro-economic factors, play on the efficiency score of a given port. There are fewer studies that focus on the role played by the inter-port competitive environment. This role remains difficult to assess. In fact, on the one hand, a port subject to high inter-port competition may record higher efficiency scores due to the pressure from the competitive environment. On the other hand, a port subject to high competition may be forced to over-invest and could therefore records a lower efficiency score. This article investigates this issue and examines how the degree of competition measured at different levels (local, regional and global level) impacts the efficiency score of a given container port. To do so, we implement a truncated regression with a parametric bootstrapping model. The model applied to information gathered for 200 container ports in 2007 and 2010 leads to the following conclusions: port efficiency decreases with competition intensity when measured in a range of 400–800 km (regional level); and the effect from competition is not significant when competition is measured at a local (less than 300 km) or at a global (more than 800 km) level. Estimates also show a tendency for ports who invested from 2007 to 2010 to experience a general decrease in efficiency scores, an element which could be explained by the time lag between the investment and the subsequent potential increase in container throughput.  相似文献   
506.
土工合成材料在黄骅港的应用   总被引:2,自引:2,他引:0  
介绍黄骅港工程中土工合成材料的应用情况,并根据现场断面监测结果,分析土工织物加筋垫层的作用效果和塑料排水板对堆场软土地基的加固效果。  相似文献   
507.
航塘港泵闸坐落于航塘港与杭州湾交汇处,工程重点保障浦东片防洪除涝,同时兼具水生态环境改善、水资源调度等功能。为了保障航塘港泵闸的安稳运行,基于BIM三维模型技术,采用水工模型试验研究工程闸后水流流态,并研究流态优化方案。试验表明,BIM技术可以有效指导物理模型制作,工程采用的优化方案整流效果较好,可减小局部高流速,减轻外河防护强度。  相似文献   
508.
徐颂 《水运工程》2001,1(3):56-60
建立大连口岸物流网有限公司,以推动大连口岸的信息化进程。  相似文献   
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