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1.
An efficient, integrated transport system iskey to the Port of Vancouver s success. "There are many ways that we can optimizethe efficiency and carrying capacity of ourtransportation infrastructure in Canada: throughtechnology, by working together, by thinkingdifferently," said Captain Gordon Houston,President & CEO of the Vancouver Port Authority.  相似文献   

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SUMMARY     
International Propeller Club Honors Capt. Wei; Figures of the World Shipping (China) Summit 2005 Robert Mundell, Father of the Euro;Akimitsu Ashida, President Executive Officer, MOL; Houston Sufficient support infrastructure, carrying capacity needed.  相似文献   

4.
ABSTRACTS     
《中国远洋航务》2014,(10):10-11
China announced recently new measures for the Yangtze River economic belt
A State Council guideline released recently seeks to enhance the traffic capacity of the river and its tributaries. An integrated lransport system will connect roads, railways and air routes by 2020. The Yangtze River Delta is a key pole in China's economic growth and the central and western regions boast the largest space for China's economic growth.  相似文献   

5.
Real-time modeling and simulation of flight system are the key parts of simulator. After describing the architecture of simulator for a newer fighter, author presents the composition of flight system and its mathematic models. In this paper, aircraft is regarded as an elastic flight body. And a new integrated algorithm which can remedy the shortcoming of Euler method and four-element method is used to calculate the Eulerian angles of aircraft. Finally, the software implementation of the flight system is given in the paper.  相似文献   

6.
In order to improve the safety properties of an offloading system with side-by-side (SBS) mooring in which the FPSO is moored by a yoke system in the field of BZ25-1, it is necessary to analyze those properties. According to the experience of similar projects, tow strategies of different offloading arrangements were discussed by using the 3-D radiation/diffraction theory and quasi-static time domain method to assess their respective safety properties. Through the safety assessment analysis of different arrangement comparisons, various ways to improve the safety properties of offloading systems with side-by-side mooring were verified by analyzing the tension in the mooring lines and the fender deflection. Through comparison it can be concluded that by enlarging the key factors properly, including the size of the fenders and the hawsers as well as the number of hawsers, a better safety performance can be achieved.  相似文献   

7.
The performance of a sonar system is closely related to the marine environment and the target characteristics. When dealing with the echoes of a traditional active sonar system, the sonar designers often do not take into account the influence of the environmental information and prior knowledge perceived by sonar receivers, making it difficult to obtain desired processing results. Based on the basic principle and key technology of sonar, this paper proposed a cognition-based intelligent sonar system in theory--cognitive sonar. Cognitive sonar is capable of jointly optimizing the transmission waveform and receiver according to the changes of environment so that its detection and identification performance can be significantly improved.  相似文献   

8.
The principles of the SINS/DVL integrated navigation system are introduced, and the compass status accuracy is compared. When the heading is changed, the dead reckoning algorithm using the heading information of the SINS (Strapdown inertial navigation systems) and DVL (doppler velocity log) is adopted to substitute the SINS/DVL integrated system. The simulation results show that the method can improve the accuracy of integrated navigation system when AUV (autonomous underwater vehicle) is in motion.  相似文献   

9.
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   

10.
A route optimization methodology in the frame of an onboard decision support/guidance system for the ship’s master has been developed and is presented in this paper.The method aims at the minimization of the fuel voyage cost and the risks related to the ship’s seakeeping performance expected to be within acceptable limits of voyage duration.Parts of this methodology were implemented by interfacing alternative probability assessment methods,such as Monte Carlo,first order reliability method(FORM) and second order reliability method(SORM),and a 3-D seakeeping code,including a software tool for the calculation of the added resistance in waves of NTUA-SDL.The entire system was integrated within the probabilistic analysis software PROBAN.Two of the main modules for the calculation of added resistance and the probabilistic assessment for the considered seakeeping hazards with respect to exceedance levels of predefined threshold values are herein elaborated and validation studies proved their efficiency in view of their implementation into an on-board optimization system.  相似文献   

11.
Short baseline system (SBL), which is a kind of underwater acoustic locating technology, has widely applicable value. In order to examine the capability of ship model design, the ship model experimentation should have high accuracy. This paper focuses on the key techniques of high accuracy locating system, including high accuracy sub-array position emendation, divisional locating, anti multi-path interference measure, etc. Experiments show that the SBL locating systems has received the satisfying effect owing to these key techniques proposed in this paper.  相似文献   

12.
This paper describes an analytical investigation into synchrophasing, a vibration control strategy on a machinery installation in which two rotational machines are attached to a beam-like raft by discrete resilient isolators. Forces and moments introduced by sources are considered, which effectively represent a practical engineering system. Adjusting the relative phase angle between the machines has been theoretically demonstrated to greatly reduce the cost function, which is defined as the sum of velocity squares of attaching points on the raft at each frequency of interest. The effect of the position of the machine is also investigated. Results show that altering the position of the secondary source may cause a slight change to the mode shape of the composite system and therefore change the optimum phase between the two machines. Although the analysis is based on a one-dimensional Euler–Bernoulli beam and each machine is considered as a rigid-body, a key principle can be derived from the results. However, the factors that can influence the synchrophasing control performance would become coupled and highly complicated. This condition has to be considered in practice.  相似文献   

13.
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   

14.
More than 90 per cent of China's for eign trade goes through ports. In 2002, the number of containers handled by Chinese ports amounted to 37 million TEUs(twenty-foot equivalent units), about 30 times the volume of 1989. China hopes to increase the capacity of its national ports to 3 billion tons by 2010.  相似文献   

15.
Experimental investigations into the collapse behavior of a box-shape hull girder subjected to extreme wave-induced loads are presented.The experiment was performed using a scaled model in a tank.In the middle of the scaled model,sacrificial specimens with circular pillar and trough shapes which respectively show different bending moment-displacement characteristics were mounted to compare the dynamic collapse characteristics of the hull girder in waves.The specimens were designed by using finite element(FE)-analysis.Prior to the tank tests,static four-point-bending tests were conducted to detect the load-carrying capacity of the hull girder.It was shown that the load-carrying capacity of a ship including reduction of the capacity after the ultimate strength can be reproduced experimentally by employing the trough type specimens.Tank tests using these specimens were performed under a focused wave in which the hull girder collapses under once and repetitive focused waves.It was shown from the multiple collapse tests that the increase rate of collapse becomes higher once the load-carrying capacity enters the reduction path while the increase rate is lower before reaching the ultimate strength.  相似文献   

16.
The control system determines the effectiveness of an underwater hydraulic shock shovel. This paper begins by analyzing the working principles of these shovels and explains the importance of their control systems. A new type of control system’s mathematical model was built and analyzed according to those principles. Since the initial control system’s response time could not fulfill the design requirements, a PID controller was added to the control system. System response time was still slower than required, so a neural network was added to nonlinearly regulate the proportional element, integral element and derivative element coefficients of the PID controller. After these improvements to the control system, system parameters fulfilled the design requirements. The working performance of electrically-controlled parts such as the rapidly moving high speed switch valve is largely determined by the control system. Normal control methods generally can’t satisfy a shovel’s requirements, so advanced and normal control methods were combined to improve the control system, bringing good results.  相似文献   

17.
More than 90 per cent of China‘s for eign trade goes through ports. In 2002, the number of containers handled by Chinese ports amounted to 37 million TEUs (twenty-foot equivalent units), about 30 times the volume of 1989. China hopes to increase the capacity of its national ports to 3 billion tons by 2010.  相似文献   

18.
As an independent industry, the emergence of the classification society was perhaps the demand of beneficial interests between shipowners, cargo owners and insurers at the earliest time. Today, as an indispensable link of the international maritime industry, class role has changed fundamentally. Start off from the demand of the insurersSeaborne trade, transport and insurance industries began to emerge successively in the 17th century. The massive risk and benefit brought by seaborne transport provided a difficult problem to insurers.  相似文献   

19.
Through analyzing the roll model of the integrated system of fin and anti-rolling tank, this paper uses binomial equation to simplify the module and check how the approximate parameters simulate the original function. Based on the simplified module, the influence of fin and anti-rolling tank on the coefficient items of the roll module is discussed, and the influencing factors between fin and anti-rolling tank are analysed. And through simulation, the influence of action between fin and anti-rolling tank on the static characteristics, and the integrated stabilization effect, are analyzed.  相似文献   

20.
Energy optimization is one of the key problems for ship roll reduction systems in the last decade. According to the nonlinear characteristics of ship motion, the four degrees of freedom nonlinear model of Fin/Rudder roll stabilization can be established. This paper analyzes energy consumption caused by overcoming the resistance and the yaw, which is added to the fin/rudder roll stabilization system as new performance index. In order to achieve the purpose of the roll reduction, ship course keeping and energy optimization, the self-tuning PID controller based on the multi-objective genetic algorithm(MOGA) method is used to optimize performance index. In addition, random weight coefficient is adopted to build a multi-objective genetic algorithm optimization model. The objective function is improved so that the objective function can be normalized to a constant level. Simulation results showed that the control method based on MOGA, compared with the traditional control method, not only improves the efficiency of roll stabilization and yaw control precision, but also optimizes the energy of the system. The proposed methodology can get a better performance at different sea states.  相似文献   

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