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1.
The BIMCO/ISF 2000 Manpower Update is probably the most comprehensive study of the global supply and demand for merchant seafarers thathas so far been undertaken,building on data amassed by earlier studies conducted in 1990 and 1995.This report has two main purposes: to describe the worldwide supply and demand situation for seafarers in 2000,and to make predictions as to the likely situation in 5-10 years' time,so that the industry can.anticipate changes and,if appropriate,take necessary corrective action.This 2000 Update has also attempted to take full account of the views of senior executives in the shipping industry,providing a synthesis of academic analysis (using the expertise of Warwick University) with the practical experience of international employers.  相似文献   

2.
The medium - large caliber naval gun is still playing an important role in modern war. The development of highly automatic Shell Raising and Feeding System (SRFS) in the world has been briefly outlined. Several typical SRFS of medium-large caliber naval guns have been analyzed. A re-design of the system is introduced, in which systematic design method has been used to demonstrate its feasibility. The design goal of the system is to realize rapid shell feeding, with application to many types of shells, quick change of shell types , accurate and reliable feeding operation, simple mechanical structure and easy realization of shell withdrawing.  相似文献   

3.
A new reasonably perfect dynamic mathematic model has been established for condenser used in ship nuclear powerplant according to its structural features and Operating principle. The model has been solved by the Runge-Kutta method. Andan analysis program has been developed for dynamic numerical simulation under steady operation condition, disturbance condi-tion, and accident condition. The dynamic characteristics of condenser has been calculated and analyzed under several kinds of  相似文献   

4.
A practical antenna has been designed and developed for INMARSAT mobile satellite communications. The design uses low cost materials such as foam and copper foil to create a stacked microstrip antenna array. Several techniques were adopted to enhance the impedance bandwidth and axial ratio bandwidth. The final design parameters were optimized by EM simulation. Finally, the L-strip fed six-element stacked microstrip antenna array was constructed and tested. Simulated and measured results show that in the whole INMARSAT work band, the VSWR of the antenna is less than 1.6, its antenna gain is higher than 15dB and wide-angle axial ratio (AR) 3dB is more than 21°. The antenna has been successfully used with a HNS 9201 terminal.  相似文献   

5.
Shipping News     
Chao Yang's branches in China Chao Yang has been licensed by Chinese governmenmt to set its branch offices in China. Now it provides weekly services from South Korea to the main ports of mainland. The company's handling capacity of China's imports and exports last year has topped 35 TEUs.  相似文献   

6.
The development of studying flexible pipe bend reinforced by Kevlar fibers   总被引:3,自引:0,他引:3  
The flexible pipe bend can not only reduce the structural vibration and fluid noise in pipeline, but also realize the flexible connection of a horizontal line and a vertical line and compensate the displacement of three dimensions produced by the shock or vibration of pipeline in the special situations. Up to now, little attention has been paid to study the flexible pipe bend applied in the pipeline of medium or high pressure, because no appropriate framework materials can be used to reinforce it which must endure the burst pressure higher than 10 MPa. The investigation shows that it is possible to produce the flexible pipe bend of medium or high pressure if such fibers with high performance as Kevlar fibers are used to be its reinforced materials. However, its structural designing theory, manufacturing technology and measuring techniques aren‘t yet perfect and systematic, which leads to the instability of the performance of products. Furthermore, few references about its research can be seen. Therefore, it is necessary to systematically and thoroughly develop the structural designing theory, manufacture technology and measuring techniques of flexible pipe bend.  相似文献   

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Due to China's huge demand in iron and steel the iron ore volume to be imported has increased largely. The local governments and port authorities at all levels are putting more and more efforts on port infrastructure construction in order to satisfy iron ore import. However, the operation capacity of docks of China is still not sufficient. The gap between demand and supply has attracted a large mount of social investment to put on iron ore wharves facilities construction, especially after Port Administration System Reform Rules was published in 2002. So it is clear that three parties like steel mills, ship owners and port authorities surely will seek more cooperation in this field.  相似文献   

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A classical time-varying signal,the multi-component Chirp signal has been widely used and the ability to estimate its instantaneous frequency(IF) is very useful. But in noisy environments,it is hard to estimate the IF of a multi-component Chirp signal accurately. Wigner distribution maxima(WDM) are usually utilized for this estimation. But in practice,estimation bias increases when some points deviate from the true IF in high noise environments. This paper presents a new method of multi-component Chirp signal IF estimation named Wigner Viterbi fit(WVF) ,based on Wigner-Ville distribution(WVD) and the Viterbi algorithm. First,we transform the WVD of the Chirp signal into digital image,and apply the Viterbi algorithm to separate the components and estimate their IF. At last,we establish a linear model to fit the estimation results. Theoretical analysis and simulation results prove that this new method has high precision and better performance than WDM in high noise environments,and better suppression of interference and the edge effect. Compared with WDM,WVF can reduce the mean square error(MSE) by 50% when the signal to noise ration(SNR) is in the range of -15dB to -11dB. WVF is an effective and promising IF estimation method.  相似文献   

13.
YuLaibao 《集装箱化》1998,(12):30-31
Featuring modemization and high efficiency,multimodalism constitutes the most advanced stage of container transport in its development.With its salient superiorities and along with the process of global econcmic integration and technological progress,container multimodal transport has been popularized in many developed countries,and in some developing countries as well.  相似文献   

14.
A new multi-level analysis method of introducing the super-element modeling method, derived from the multi-level analysis method first proposed by O. F. Hughes, has been proposed in this paper to solve the problem of high time cost in adopting a rational-based optimal design method for ship structural design. Furthermore,the method was verified by its effective application in optimization of the mid-ship section of a container ship. A full 3-D FEM model of a ship,suffering static and quasi-static loads, was used as the analyzing object for evaluating the structural performance of the mid-ship module, including static strength and buckling performance. Research results reveal that this new method could substantially reduce the computational cost of the rational-based optimization problem without decreasing its accuracy, which increases the feasibility and economic efficiency of using a rational-based optimal design method in ship structural design.  相似文献   

15.
On 3 May 2003,a COSCO cargo carrier “Fu Shan Hai“ collided with a Polish containership in the sea east of Denmark and sank later. It was reported that the insurance premium for M/V “Fu Shan Hai“ is as high as US$30m. It is the ever large claim case in the marine insurance history of the People‘s Insurance Company of China (PICC). Though PICC launched its emergent compensation procedure and paid 70m yuan (RMB) to COSCO, this is far from enough to fill the hole. The “Fu Shan Hai“ accident gave a hard strike on the marine insurance market, worsening the difficult situation of marine insurance in China. In recent years, we have often heard the calling for making China a “large shipping and shipbuilding nation“, while our marine insurance market has been in stagnancy, which disappoints those insurance tycoons who have been kept waiting for long time.  相似文献   

16.
大型加强板结构焊接顺序的效果研究(英文)   总被引:1,自引:0,他引:1  
Welding sequence has a significant effect on distortion pattern of large orthogonally stiffened panels normally used in ships and offshore structures. These deformations adversely affect the subsequent fitup and alignment of the adjacent panels. It may also result in loss of structural integrity. These panels primarily suffer from angular and buckling distortions. The extent of distortion depends on several parameters such as welding speed, plate thickness, welding current, voltage, restraints applied to the job while welding, thermal history as well as sequence of welding. Numerical modeling of welding and experimental validation of the FE model has been carried out for estimation of thermal history and resulting distortions. In the present work an FE model has been developed for studying the effect of welding sequence on the distortion pattern and its magnitude in fabrication of orthogonally stiffened plate panels.  相似文献   

17.
Xing Dan 《中国船检》2013,(9):124-125
In recent years,Chinese government’s policy support to the LNG-powered ship has been constantly increasing.The"Guidance on speeding up LNG fuel application in the shipping industry"has been issued with an intent to reserve a portion of fund for ship modification from the 1.5 billion Yuan special fund for energy-saving and emission reduction,so that 200m Yuan subsidies could be made available by the means of"award instead of subsidy".Meanwhile,the guidance determines that the highest price of LNG should not exceed 75%of the fuel oil price.  相似文献   

18.
WANG Xiao-hua 《水道港口》2010,31(5):320-320
In the high-energy environment of coastal seas and estuaries,strong sediment resuspension/ deposition events are driven by surface waves,tides,winds and buoyancy driven currents.In recent years,A POM based three-dimensional,wave-current coupled,sediment transport model has been developed by the University of New South Wales.This paper presents several examples of the model applications to study sediment dynamics in the environments where forcings such as waves,tides,and winds are equally important to affect sediment fluxes and distributions.Firstly,the sediment transport model coupled to the Yellow Sea general circulation model and a third generation wave model SWAN was implemented in the Yellow Sea to study the dynamics of the sediment transport and resuspension in the northern Jiangsu shoal-wate(rNJSW).The sediment distributions and fluxes and their inter-annual variability were studied by realistic numerical simulations.The study found that the surface waves played a dominant role over the tides to form the turbidity maxima along the muddy coast of NJSW. Secondly,the sediment transport model was used to explore the effect of suspended sediment-induced stratification in the bottom boundary laye(rBBL).The model uses a re-parameterized bottom drag coefficient Cd that incorporates a linear stability function of flux Richardson number Rf.The study has shown that the sediment induced stratification in the BBL reduces the vertical eddy viscosity and bottom shear stress in comparison with the model prediction in a neutrally stratified BBL.In response to these apparent reductions,the tidal current shear is increased and sediments are abnormally concentrated within a thin wall layer that is overlain by a thicker layer with much smaller concentration.The formation of this fluid-mud layer near the seabed has led to a significant reduction in the total sediment transport.This study contributes to the understanding of formations of tidal flats along the coasts of turbid seas and estuaries.  相似文献   

19.
The methodology to obtain the non-linear roll damping from decay tests is very old. It has been proposed by Froude in the 19th century and used from then on. Behind it there is a quadratic model [θ│θ│] for the damping and a subsequent equivalent linearization. Probably all model basin in the world follows this approach to assess the damping from a decay test. This is well documented and so is the methods to get the p1-p2 coefficients. This is very general in the sense that in principle,it could be applied t...  相似文献   

20.
On behalf of the Senate of the Free and Hanseatic City of Hamburg it is a great pleasure for me to congratulate China Ocean Shipping (Group) Company on its fortieth anniversary. These four decades have been an impressive story of success for the company. It has become one of the leading players in container shipping, bulk and general cargo transportation and now owns and operates more than 500 merchant  相似文献   

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