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991.
Hamid Bazargan Hamid Bahai Amin Aminzadeh–Gohari 《Journal of Marine Science and Technology》2007,12(1):34-42
This study presents a new method for calculating return values. The essence of the method is that it utilizes nonstationary
data to calculate the return value for a region in the Northeast Pacific. The nonstationary data was obtained from a model
which was previously developed for the behavior of the significant wave height as a function of time in the region. The method
is illustrated by convolving two generalized Pareto distribution functions fitted to two parts of the model, computing a suitable
extreme value from the new distribution function, and calculating the return value using this extreme value. 相似文献
992.
A new marine propulsion system 总被引:1,自引:0,他引:1
HANWei-shi LIUTao 《船舶与海洋工程学报》2003,2(1):30-34
A new marine propulsion system is proposed . A small liquid sodium cooled reactor acts as prime mover; alkali-metal thermal-to-electric conversion (AMTEC) cells are employed to convert the heat energy to electricity; superconducting magneto-hydrodynamic thruster combined with spray-water thruster works as propulsion. The configuration and characteristics of this system are described. Such a nuclear-powered propulsion system is not only free of noise, but also has high reliability and efficiency. It would be a preferable propulsion system for ships in the future。 相似文献
993.
Stanislaw Raczynski 《Journal of Marine Science and Technology》2007,12(1):15-21
A commonly used mathematical tool in vehicle dynamics simulation is the ordinary differential equation. However, in some situations,
these equations may not be sufficient to solve problems. For robust flight, surface ship or submarine control design, safety
assessment, missile and aircraft guidance, the influence of disturbances, and differential games of pursuit–evasion, more
versatile tools are needed. The differential inclusion (DI) is a generalization of a differential equation that can be extremely
useful. The solution of a DI is not just a model trajectory or a set of trajectories obtained by a randomization of the original
problem. The solution is a reachable set, and it is a deterministic object. A differential inclusion solver and its application
to vessel movement are described. Compared to previous publications on the DI solver, the new feature is an implementation
of the fuzzy sets technique to improve the resulting images. It is pointed out that the reachable sets cannot be assessed
properly while treating the uncertain variables as random. The application of the DI solver can give a proper view of the
regions in the state space where all the possible model trajectories belong. 相似文献
994.
ZHANG Xu ZHANG Jia-tai LIU Gang YUAN S J WANG Z R College of Mechanical Electrical Engineering Harbin Engineering University Harbin China College of Material Science Engineering Harbin Institute of Technology Harbin China 《船舶与海洋工程学报》2002,1(1):77-80
On the basis of the principle of dieless hydrobulging technology, a novel hydrobulging technology for manufacturinghyperbolic plates is proposed. First, a toroidal pipe elbow or a partial toroidal pipe elbow is formed, then the single hydrobulgedstructure can be cut up into some desired plates. It is proved by experiments and finite element simulation that manufacturingtechnology of hyperbolic plates adopting integrated hydrobulging forming technology is feasible. 相似文献
995.
LIU Peter Xiao-ping 《船舶与海洋工程学报》2002,1(2):46-50
An Internet-based teleoperation platform for Mobile Robot is introduced in this paper. The hardware of the system mainly consists of a mobile robot. Its software employs client-server architecture for robot control and feedback information display . Different communication protocols are adopted according to the characteristics of message exchanged between the robot server and the client. The user interface is designed for the purpose of interaction. The great benefit of this client-server architecture is that the client software is insulated from the lowest level details of the mobile robot. Thus, it is very easy to implement and test new advanced teleoperation control algorithms, interface designs and applications on this platform without large programming work. 相似文献
996.
本文采用心阻抗图测定了76例4岁~12岁心肌炎患儿的左室功能,并以54名同龄健康小儿作对照,以PEP、LVETI、PEP/LVET、Q-Z、SV、CO、CI、HI作为观察指标,有1项以上异常者共55人,占72.4%,各项指标中,PEP/LVET、PEP、Q-Z较LVETL、SV、CO、CI和HI敏感。若以PEP/LVET>0.35作为衡量心功能异常的主要指标,则慢性期心功能异常发生率最高(81.0%),其次为急性期(36.7%),而迁延期患儿PEP/LVET比值均在正常范围。重型患儿心功能均异常,且PEP/LVET>0.40,而心功能正常的患儿病情均较轻。这一检查方法在协助诊断、判断病情、估计预后及观察疗效等方面均有一定价值。 相似文献
997.
LIU Jian-cheng LIU Xue-min XU Yu-ruCollege of Shipbuilding Engineering Harbin Engineering University Harbin China 《船舶与海洋工程学报》2002,1(1):21-25
In this paper, maximum-likelihood (ML) and its relaxation algorithm, which are used to identify the mathematicsmodel of an underwater vehicle(UV), arc discussed. With the trial data of zigzag tests, the hydrodynamic derivatives of theUV were estimated, and the relaxation algorithm is confirmed to have better astringency from the contrast between the twomethods.Then a simulation environment based on these parameters is established to verify the validity and effect of these meth-ods. The result shows the model is credible and the methods are very useful for the research of maneuverability and adaptivecontrol of underwater vehicles. 相似文献
998.
本文阐述了轨道衡辅助设计及绘图系统 GDHCADD 的内容、功能及其应用.该系统采用图块拼装方式完成轨道衡工程的施工设计或竣工图,适用于轨道衡为 GGG-22F 及 LT-03两种型号的多种不同组合情况,并采用绘图作业管理程序 GJM 和 WJMF,以实现系统的组织. 相似文献
999.
1000.
FEA for designing of floating raft shock-resistant system 总被引:2,自引:0,他引:2
ZHAOYing-long HELin HUANGYing-yun WANGYu 《船舶与海洋工程学报》2003,2(1):24-29
Choosing the equipment with good shock-resistant performance and taking shock protection measures while designing the onboard settings, the safety of onboard settings can be assured when warships, especially submarine subjected to non-contact underwater explosion, that is, these means can be used to limit the rattlespace (i. e. , the maximum displacement of the equipment relative to the base) and the peak acceleration experienced by the equipment. Using shock-resistant equipments is one of shock protection means. The shock-resistant performance of the shock-resistant equipments should be verified in the design phase of the equipments. The FEA (finite element analysis) software, for example, MSC. NASTRANw, can be used to verify the shock-resistant performance. MSC. PATRAN and MSC. NASTRAN are used for modeling and analyzing the floating raft vibration isolating equipment. The model of the floating raft and the floating raft vibration isolating system are theoretically analyzed and calculated, and the analysis results are in agreement with the test results. The transient response analysis of the system model follows the modal analysis of the floating raft vibration isolating system. And it is used to verify the shock-resistant performance. The analysis and calculation method used in this paper can be used to analyze the shock-resistant performance of onboard shock-resistant equipments. 相似文献