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1.
《集装箱化》1998,(10):31-31
In order to standardize the market management of china‘s intemational container multimodal transport and promote china‘s foreign trade,the ministry of commuications and the ministry of railways of the people‘s republic of china(hereinfter referred to as the two ministries)jointly promulgated on march1997 the “regulations for the managemetnt of intemational container multimodal transport ”(hereinafter referred to as the regulations )and began to enforce the regulations on oct.1.1997.  相似文献   

2.
贾大山 《集装箱化》1998,(11):18-18,37
Over the recent ten years,China‘s container transport has witnessed a tremendous development side by side with china‘s successful development of foreign trade,owing to the fact that more and more coastal and inland river ports have gone for container transport in succession,  相似文献   

3.
Although China is relatively late in the trial use of LNG ships,she has become the front runner in the promotion of LNG ships.The launch of China’s first LNG/diesel hybrid pilot inland waterway ship in 2010 became the prelude for the application of LNG as bunker fuel for water transportation.At present,with the speeding up of the layout of LNG stations of energy companies,and the increase of the government’s policy support,there is the trend of fast development of"oil converted to  相似文献   

4.
UUV外形和总体布局分析   总被引:1,自引:0,他引:1  
The construction and shape of UUVs are described in the paper.UUV design is the shape of the overall design of unmanned underwater vehicle should first be resolved UUV underwater vehicle directly affects the shape of the resistance and noise,which is related to energy,payload,maneuverability and concealment UUV problem The main characteristic and parameter tables for foreign torpedo shape,flat shape and anomalous shape are also given in the paper.The general layout of typical foreign UUVs is analyzed in detail.And the total layout figure and interior constructive figure are introduced.Torpedo-type because of its good water power and low noise,no one has been the main form of underwater vehicle-like,and many designers are now highly favored because of its stable performance,anti-environmental interference capability.Other irregular shapes designed primarily for the completion of a specific task,according to the specific environment and mission requirements.According to comparing and summarizing,some suggestions and conclusions are presented.  相似文献   

5.
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   

6.
China has led developing countries in direct foreign investment for eight consecutive years, with an inflow of more than US$40 billion of international capital annually. China has become a real hotspot of investment favored by worldwide investors. What is the role foreign investment has played in China's economic development over the past years? According to an analysis report recently released by the National Information Center, during the two decades between 1980-99, of the 9.7-percent average annual growth rate of the GDP, 2.7 percentage points were contributed directly or indirectly by foreign capital utilization. 1. How Does Foreign Capital Stimulate China's Economic Growth?  相似文献   

7.
A constructive method was presented to design a global robust and adaptive output feedback controller for dynamic positioning of surface ships under environmental disturbances induced by waves, wind, and ocean currents. The ship’s parameters were not required to be known. An adaptive observer was first designed to estimate the ship’s velocities and parameters. The ship position measurements were also passed through the adaptive observer to reduce high frequency measurement noise from entering the control system. Using these estimate signals, the control was then designed based on Lyapunov’s direct method to force the ship’s position and orientation to globally asymptotically converge to desired values. Simulation results illustrate the effectiveness of the proposed control system. In conclusion, the paper presented a new method to design an effective control system for dynamic positioning of surface ships.  相似文献   

8.
The exhaust volute is a device that can change the exhaust direction of the ship’s gas turbine to reduce the flow loss of the high-temperature and high-speed turbine exhaust gas in the box-type exhaust volute, thereby improving its power output performance. This paper first investigates the internal flow field characteristics of the exhaust volute via numerical simulation and reveals the main source of the internal resistance loss of the volute. On the premise of not affecting the installation s...  相似文献   

9.
The vibration isolation performances of typical hull structure with viscoelastic interlayer are analyzed according to wave theory,and the influences of interlayer Young’s modulus and length on the vibration reduction are discussed.The theoretical analysis shows that combination of polyurethane interlayer with blocking mass can enhance the vibration isolation performance and expand isolation frequency band.In order to verify the effectiveness of polyurethane interlayer,the model test of power cabin’s vibration is carried out.The test data shows that the reduction of 20–1 000 Hz variation acoustic level at hull shell is more than 5 dB.  相似文献   

10.
To provide a simulation system platform for designing and debugging a small autonomous underwater vehicle’s (AUV) motion controller, a six-degree of freedom (6-DOF) dynamic model for AUV controlled by thruster and fins with appendages is examined. Based on the dynamic model, a simulation system for the AUV’s motion is established. The different kinds of typical motions are simulated to analyze the motion performance and the maneuverability of the AUV. In order to evaluate the influences of appendages on the motion performance of the AUV, simulations of the AUV with and without appendages are performed and compared. The results demonstrate the AUV has good maneuverability with and without appendages.  相似文献   

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