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By the mind-1960s there was a great deal of inefficiency in the Europe/Australia liner trade which reflected the ultra-conservative management of the British shipping lines under the benign protection of the conference system. Containerization per se was not necessary to realising a large gain in efficiency and therefore permitting a reduction in the level of freight rates. The introduction of containerization with cellular container ships and under the aegis of a strengthened conference monopoly has meant that shippers have been denied much of the potenital beneifit.  相似文献   

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From 2000s, there have been three forces provoking slow steaming practice in the liner industry: (1) oversupply of shipping capacity, (2) increase of bunker price and (3) environmental pressure. This paper analyses the background and the recent application of slow steaming in liner shipping. The research looks into the questions of how slow steaming can save bunker consumption and bring benefits to the environment. On the other hand, solutions are also examined to the adverse side of slow steaming practice, i.e., how it affects the container transit time. For which, a cost model is developed to demonstrate the impact of slow steaming on the revenue change, with application to the North Europe—Far East Trade as a case study. The final result shows that the optimal speed for the shipowner is correlated with the designed speed, bunker price and the price of CO2. With the increase of the bunker price and the price of CO2, the optimal speed will also increase, which means that slow steaming practice has a positive impact on the environmental protection.  相似文献   

4.
直流电动机双闭环调速系统及其SIMULINK的仿真   总被引:3,自引:0,他引:3  
韩璐 《船海工程》2003,(2):30-33
根据直流调速双闭环控制系统的工作原理,运用Simulink进行直流电动机双闭环调速系统的数学建模和系统仿真的研究,最后显示控制系统模型以及仿真结果并加以分析。  相似文献   

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Adelaide's bus system has been transformed from a government monopoly operation to a competitively tendered system with services provided by private operators under contract. The ‘Adelaide model’ has unique features, and has been considered in several international reviews of urban bus service procurement. The paper reviews the experience in Adelaide up to 2006/07. It updates previous evidence that focused on technical efficiency impacts. It particularly examines the development of the system to address allocative efficiency, in terms of the quantity, quality and market orientation of the services provided, and the consequent effects on patronage.  相似文献   

7.
We describe the operational tanker scheduling problem in detail, as it relates to Chevron Shipping Company. We review the literature and current Chevron practice. We develop a model for the scheduling situation, and describe an integer programming formulation for schedule optimization, including the feasible schedule generation process, for a realistic representation of the company scheduling practices.  相似文献   

8.
众所周知,国际航运业如今正呈现出不断增长的趋势,这缘于全球经济和贸易活动的不断扩张.  相似文献   

9.
援潜救生体系和系统的现状及发展趋势   总被引:2,自引:0,他引:2  
熊军  肖国林 《船海工程》2007,36(2):90-93
分析援潜救生系统和体系的联系与区别,介绍美国、英国、澳大利亚等国家的援潜救生系统和体系的现状及发展,提出建立我国独立的援潜救生体系和配套系统,整合资源,完善军民结合的模式,加强国际交流,加快援潜救生事业的发展。  相似文献   

10.
舰船搭载系统的发展   总被引:3,自引:2,他引:1  
杨运桃 《船海工程》2006,35(2):7-10
为了优化海军兵力结构,实现一舰多用,提出舰船搭载系统的新概念,介绍国外搭载系统发展的状况,并设想我国舰船搭载系统的发展思路。  相似文献   

11.
This review summarizes the main research findings of the multi-year oceanographic and biological studies conducted in the vicinity of the Prince Edward Archipelago during the period 1976 to 1990. The Prince Edward Islands represent a flow-through system on the mainstream of the Antarctic Circumpolar Current. Although there are no taxonomic differences between the pelagic communities of the upstream, inter-island and downstream regions, these mesoscale subsystems may operate differently. The mesoscale oceanographic and biological processes appear to be affected by the position of the Subantarctic Front (SAF) in the vicinity of the islands. Both the rich benthic community, which is supported by the local enhancement of primary production, and the strong advection of zooplankton/micronekton from the upstream region provide the food resources necessary for the survival of the huge community of land-based predators present on the islands. Collectively this is termed the ‘life-support system'. Future studies should concentrate on the meridional shifts in the position of the SAF and its influence on background productivity upstream and downstream of the Prince Edward Archipelago.  相似文献   

12.
王艾 《船海工程》2005,(3):46-48
介绍船舶自动识别系统的构成、主要特性及设备功能,分析最小控制系统的电平转换电路等技术实现方法及系统软、硬件设计要点。  相似文献   

13.
贝少军  姜艳燕 《中国海事》2011,(1):F0002-F0002
1月5日至6日,2011年交通运输部直属海事系统工作会议在福建厦门召开,会议回顾了"十一五"期间建海事发展的基本成就,总结了基本经验,勾画出了"十二五"发展的总体思路。  相似文献   

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阐述目前世界上比较成熟的闭式循环柴油机AIP及其水管理系统,并分析其特点、工作性能及关键技术和设备,为从事该项工作的有关人员提供参考.  相似文献   

16.
许艳 《中国海事》2005,(1):28-30
交通部海事局于2005年4月16日至6月15日开展了为期2个月的“整治船员持假证上船任职统一执法行动”,取得明显成效。据反馈,统一执法行动开展后的前两周,共查处假证1400余本,占到查处总数的近一半,而后期查处假证的数量相对较少。这其中不排除部分持假证的船员存有观望、侥幸心理,准备在活动之后继续使用假证的情况。为保持打假成果,防止持假证现象出现反弹,部海事局要求各局于7月1日至15日继续开展为期2周的统一执法行动。  相似文献   

17.
系泊系统非线性恢复力研究及其应用(英文)   总被引:1,自引:1,他引:1  
Mooring system plays an important role in station keeping of floating offshore structures.Coupled analysis on mooring-buoy interactions has been increasingly studied in recent years.At present,chains and wire ropes are widely used in offshore engineering practice.On the basis of mooring line statics,an explicit formulation of single mooring chain/wire rope stiffness coefficients and mooring stiffness matrix of the mooring system were derived in this article,taking into account the horizontal restoring force,vertical restoring force and their coupling terms.The nonlinearity of mooring stiffness was analyzed,and the influences of various parameters,such as material,displacement,pre-tension and water depth,were investigated.Finally some application cases of the mooring stiffness in hydrodynamic calculation were presented.Data shows that this kind of stiffness can reckon in linear and nonlinear forces of mooring system.Also,the stiffness can be used in hydrodynamic analysis to get the eigenfrequency of slow drift motions.  相似文献   

18.
海洋的环境载荷复杂和多变,而海洋的环境工况又决定着系泊系统的受力情况,因此海上系泊系统的安全越来越重要。本文针对渤海海域某水上软钢臂单点系泊系统的方案设计,基于大型水动力软件AQWA,得到目标船舶频域计算下的水动力参数和系泊系统的时域耦合动力分析结果。重点分析在不同的风浪流夹角对系泊系统受力的影响,以此预报最危险工况,为后续有关系泊结构、塔架以及连接处万向节的强度和疲劳校核提供依据。分析结论亦可为同类系泊系统提供参考。  相似文献   

19.
海洋的环境载荷复杂和多变,而海洋的环境工况又决定着系泊系统的受力情况,因此海上系泊系统的安全越来越重要。本文针对渤海海域某水上软钢臂单点系泊系统的方案设计,基于大型水动力软件 AQWA,得到目标船舶频域计算下的水动力参数和系泊系统的时域耦合动力分析结果。重点分析在不同的风浪流夹角对系泊系统受力的影响,以此预报最危险工况,为后续有关系泊结构、塔架以及连接处万向节的强度和疲劳校核提供依据。分析结论亦可为同类系泊系统提供参考。  相似文献   

20.
单剑  傅振宇 《中国修船》2011,241(4):31-33
文章主要通过对某科学考察船冰机及其冷却水系统出厂以来出现的各类故障及维护情况进行统计与分析,找出存在问题的主要原因,并提出相应的改进方案。  相似文献   

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