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1.
c Relations and TradePractice in Foreign Economic Relations and TradePractice in Foreign Economic Relations and TradePractice in Foreign Economic Relations and TradePractice in Foreign Economic Relations and TradePractice in Foreign Economic Relations and TradePractice in Foreign Economic Relations and TradePractice  相似文献   

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Background For the benefit of our overseas guests, Australia is a major trading nation. In any nation, seaports are an essential component  相似文献   

3.
I have been in oil and gas business, orthe evergy business in Japan for almost40 years at Mitsubishi Corporation. I hope myfew words will be a useful contribution totoday‘s agenda“Energy Security in Asia“and“Energy and Environment“.  相似文献   

4.
舟山群岛山雨欲来舟山群岛位于浙江杭州湾外东海之中, 由舟山本岛、岱山、长涂、普陀、桃花、六横、登步、金塘、大榭等400多个岛屿组成,总面积1200平方千米。其中舟山本岛最大,面积达523平方千米,是浙江省的重要港口,巨型海轮可自由进出,也是海军良好的  相似文献   

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So-called integrators are a new breed in the international freight transportation industry. Express carriers used to take small packages and envelopes fastest from one customer to another. The transport of documents are giving way to electronic data transfer, but the key essence of the express business, moving goods from door to door fastest  相似文献   

7.
Without effective management, protected areas are unlikely to achieve the high expectations the conservation and development sectors have for them: conserving biodiversity and alleviating poverty. Numerous marine protected area (MPA) assessment initiatives have been developed at various spatial and temporal scales, including the guidebook How is your MPA doing? These management assessments have been useful to sites to clarify and evaluate their objectives, yet efforts to examine broader regional or global patterns in MPA performance are only beginning. The authors conducted exploratory trend analyses on How is your MPA doing? indicator data collected by 24 MPAs worldwide to identify challenges and areas for future work. Wide variability across sites with regard to the indicators examined and the constructs used to measure them prevented a true meta-analysis. Managers assessed biophysical indicators more often than socioeconomic and governance constructs. Investment by the conservation community to support collecting and reporting high-quality data at the site level would enable a better understanding of the variation in MPA performance, clarify the contribution of MPAs to both biodiversity conservation and poverty alleviation, and help drive better MPA performance. The absence of rigorous and consistent monitoring protocols and instruments and a platform to turn raw MPA monitoring data into actionable information is a critical but under-recognized obstacle to cross-project learning, comparative analyses, and adaptive resource management.  相似文献   

8.
The Royal Ballet Group of Denmark, supported by the A. P. Moller-Maersk Group exclusively, will visit China and put on shows during May 8-16 on the coming 50th anniversary (May 11) of the establishment of diplomatic relationship of Sino-Denmark. The Group's relationship with China can date all the way back to 1924 when the first vessel called at Shanghai.  相似文献   

9.
SPSM and its application in cylindrical shells   总被引:1,自引:0,他引:1  
In naval architectures, the structure of prismatic shell is used widely. But there is no suitable method to analyze this kind of structure. Stiffened prismatic shell method (SPSM) presented in this paper, is one of the harmonic semi-analytic methods. Theoretically, strong stiffened structure can be analyzed economically and accurately. SPSM is based on the analytical solution of the governing differential equations for orthotropic cylindrical shells. In these differential equations, the torsional stiffness, bending stiffness and the exact position of each stiffener are taken into account with the Heaviside singular function. An algorithm is introduced, in which the actions of stiffeners on shells are replaced by external loads at each stiffener position. Stiffened shells can be computed as non-stiffened shells. Eventually, the displacement solution of the equations is acquired by the introduction of Green function. The stresses in a corrugated transverse bulkhead without pier base of an oil tanker are computed by using SPSM.  相似文献   

10.
[Objective]To investigate ship motion and load responses in realistic 3D waves and overcome the limitations of the traditional 2D wave assumption, this paper develops a method for predicting ship motion and load responses in short-crested waves. [Method]The long- and short-term responses of ship motion and load in long- and short-crested waves are numerically predicted using the spectral analysis and statistical probability methods, respectively. The influence of directional function on ship response is also numerically analyzed. Moreover, tank model tests and a large-scale model sea trial are comparatively conducted to validate the difference between ship response and statistics in long- and short-crested irregular waves. [Results]The results show that when navigating against the waves in the same sea condition, the long-crested wave assumption overestimates the statistical mean value of ship load response, but underestimates extreme load in real seas. For long-crested waves, the ship motion and acceleration power spectrum is concentrated around a certain frequency band. [Conclusion]Ship motion and load responses in realistic 3D waves are significantly different from those in 2D long-crested waves. The directional function of short-crested waves also has a significant effect on ship motion and load responses. © 2023 The Author(s).  相似文献   

11.
流固耦合问题较为复杂,通常难以通过理论推导求得,而数值模拟则能提供一种有效的解决方案,并被广泛用于船舶与海洋工程领域。流固耦合数值方法根据其网格离散方式,可以分为贴体网格方法、非贴体网格方法、重叠网格方法和粒子类方法 4类,对这4类方法的特点及研究进展进行概述并总结得出:贴体网格方法和重叠网格方法均能精确捕捉界面的变形和演化,适合高雷诺数流动问题,在考虑结构变形时一般采用贴体网格方法,而考虑复杂几何形状的刚体运动时则常采用重叠网格方法;非贴体网格方法能够避免网格的更新操作,使计算较为简单,目前多用于模拟流动控制、水下柔性仿生航行器的研发以及多体运动干扰等问题;粒子类方法因其固有的拉格朗日属性,在模拟涉及自由液面剧烈变形、砰击、爆炸等强非线性流固耦合问题中发挥着重要作用。不同的流固耦合问题属性决定了不同方法的适用性,如何选取适合的数值方法,同时结合各类方法的优势开发新的计算方法以应对更为复杂的问题,是流固耦合算法开发的重要发展方向。  相似文献   

12.
From 1949 to the early 1970s, China was almost a self-sufficient economy, and invested little in transportation infrastructure. “Ihe average invesmaent in transpotation was about 3 percent of ttxal investment (China Statistical Yearbook 1991, 133). “Ihe kilometers of rail tracks barely doubled, the amount of Oared reads increased by only 1.3 times and only thirty new port berths were built. Conversely, freight volumes grew by 21, 34, and 31 times in rail, motor, and waterway,  相似文献   

13.
Prediction of Stabilization of Ship in Random Wave   总被引:1,自引:0,他引:1  
In this paper we show thc method of energy in part with which we can get the model of random wave,and predict theroll motion of unstabilized ship and stabilized ship using the wave model.The control parameters of fin stabilizer are determinedaccording to the performance index. The simulation of the system is also made in this paper. The comparison of the simulationwith real ship indicates that the method can be used in the prediction of roll motion of a stabilized ship in random wave.  相似文献   

14.
The effect of the severe acute res piratory syndrome(SARS) cannot reverse the general trend of the Chinese economy, which is entering another economic growth spurt and gaining momentum. The SARS outbreak is likely to slow down the pace of China's economic growth by 0.5-1.2 percentage points, the State  相似文献   

15.
A new method of catastrophe control is described in one dimension nonlinear system. Catastrophe control based on catastrophe theory is a brand new area for control theory. A certain catastrophe is created at a desired location by appropriate control, which has preferred properties. Washout filter is presented and applied to preserve the original equilibrium of a system.Washout filter aided dynamic feedback controller is developed for the creation of eatastrophe, and an example is given to illustrate the process. Catastrophe control may provide a new way of designing warning signals of impending collapse or catastrophe for monitoring and control purposes.  相似文献   

16.
This "rutter for piracy" begins with a brief update on contemporary piratical incidents and a short review of books and collections of articles dedicated to the topic of piracy, before presenting the ground-breaking group of scholarly essays which make up WMU Journal of Maritime Affairs' special issue on piracy at sea.  相似文献   

17.
EDI is an abbreviation for Electronic Data Interchange. It can make different enterprise and organization interchange trade and commercial datas through Computers in according with the standardized specification. Since it can save various of documents,we also call it"paperless" operation. The development of information technique from primary to advanced, which computers had been used as main part,involves three stages: The first stage is that computers bad been used to replace man to process various of business and documents inside the enterprise. The second stage is the network sys-  相似文献   

18.
While bidding farewell to the 20th century and ushering in the new 21st century, I'm overwhelmed in excitement and enthusiasm. Looking back to the performance of China's economy last year, I'm more  相似文献   

19.
Water hydraulic systems have provoked major interest because of the human friendly and environmental safety aspects. Piston pump is one of the most frequently used hydraulic units in recent engineering technique. In water hydraulic piston pump, poor lubrication is more likely to happen than in oil hydraulic one because of difference in properties between water and oil. So there are some key problems such as corrosive wear and erosion, which are investigated briefly. Many new materials have been developed, which give longer life expectancies with water without corrosion and erosion. A new type of seawater hydraulic piston pumps with better suction characteristics had been developed at HUST. Much of this research has concentrated on new materials, structure and experiments, which are also specially introduced.  相似文献   

20.
2004 is a good year for global shipping and shipbuilding. Under such situation, how about the develop-ment of China Classification Society(CCS), the main force to perform shipsurvey in China? After a…  相似文献   

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