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Optimization Model for Environmental Stress Screening of Electronic Components

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Journal of Systems Engineering and Electronics 2001年第1期12卷 29-33页

作者： Li Fang Institute of Systems Engineering, HUST, Wuhan 430074, P. R. China Zhu Cheng & Wang Wei Dept. of Management Engineering, naval University of Engineering, Wuhan 430033, P. R. China Institute of Systems Engineering HUST Wuhan 430074 P. R. China Dept. of Management Engineering Naval University of Engineering Wuhan 43003 P. R. China

Environmental stress screening (ESS) is a technological process to reduce the costly early field failure of electronic components. This paper builds an optimization model for ESS of electronic components to obtain the optimal ESS duration. The failure phenomena of ESS are modeled by mixed distribution, and optimal ESS duration is defined by maximizing life-cycle cost savings under the condition of meeting reliability requirement.

关键词： Electric fields Environmental testing Failure analysis Life cycle Mathematical models Optimization Reliability

Economic Development and the QPMSLP of the Industrial Allocation of Foreign Capital

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Systems Science and Systems Engineering 1998年第3期8卷 91-98页

作者： JIAO Jiwen Qingdao naval Submarine Academy,Qingdao 266071 WU Haihua Hsin Ten Institute of International Economics, Qingdao University, Qingdao 266071

In literatrue , the standard linear programming model of the industrial allocation of foreign capital is given. On the basis of this, each technical parameter of the model will be randomized, so that the restricted conditions in period t+1 are destroyed, the compensation problem in period t+2 is further studied. Then the more practical Quadratic Programming Model in Stochastic Linear Programming (QPMSLP) is set up. Finally, the concluding remarks of the model are given.

关键词： QPMSLP economic development foreign capital industrial allocation

RESEARCH ON HYDRODYNAMIC FORCES OF CAVITATING GRID FINS

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Journal of Hydrodynamics 2005年第2期17卷 148-153页

作者： FUHui-ping LUChuan-jing LIJie WULei SchoolofnavalArchitecture OceanandCivilEngineeringShanghaiJiaotongUniversityShanghai200030China

Hydrodynamic forces and flow pattern of four kinds of cavitating grid fins with cavitation number from 2.5 to 0.25 were simulated numerically with a bubble two-phase flow model embodied in the commercial CFD code Fluent 6.0. Comparison with experimental datum showed that rules of hydrodynamic forces changing with cavitation number were coordinated with experiment, and cavitation made the ratio of lift to resistance decrease. Calculated axial force and chordal pressure center in all-wetted condition or those at cavitation number less than 0.75 agreed well with experiments. Normal force in all-wetted condition was less by 20 per cent. The differences between computation and experiment in the total range of cavitation number were mainly because that the incipient cavitation number in computation was less than that at experiment.

关键词： grid fin cavitation hydrodynamic force

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非正态变量下结构可靠性的概率积分方法

上海交通大学学报 1997年第11期31卷 145-148页

作者：张立上海交通大学船舶与海洋工程学院

通过对结构可靠性问题中计算失效概率积分经典方法不足之处的研究，提出了一种更为有效和精确的计算基本随机变量分布为非正态分布，而且极限状态函数为非线性时的概率积分方法．

关键词：结构可靠性概率积分非正态分布

Influence of dynamic factors on ice rafting

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Acta Oceanologica Sinica 2010年第5期29卷 21-26页

作者： LI Chunhua SUN Hequan National Marine Environmental Forecasting Center Beijing 100081 China Dalian naval Academy Dalian 116018 China

Theoretical analysis and numerical simulation have been applied to researching the effect of wave,current and wind on the ice *** analytical results show that wave is the key factor for ice *** process of ice rafting is simulated using the discrete element *** simulated results show that the distortion or flexure breakage happens firstly,then followed by ice *** comprehensively analysed results show that the ice is easily rafted on the simultaneity action of wave,current and wind,and the action of wave can＇t be ***,the rafted ice length increases with the enhancive force of ocean current and wind.

关键词： sea ice rafted ice Bohai Sea

NUMERICAL INVESTIGATION ON THE AEROELASTIC BEHAVIOR OF AN AIRSHIP WITH HULL-FIN CONFIGURATION

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Journal of Hydrodynamics 2010年第2期22卷 207-213页

作者： LIU Jian-min LU Chuan-jing - XUE Lei-ping Marine Engineering Institute Jimei University Xiamen 361021 China School of naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University Shanghai 200240China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China

Numerical investigation was conducted on an airship of hull-fin configuration for aerodynamic and aeroelastic characteristics in three-dimensional viscous *** mathematical model was built and the corresponding numerical code was developed for the fluid-structure interaction *** governing equations of the viscous flow with LL-Low Reynolds modified model were solved by the standard SIMPLE algorithm based on the finite volume method.A fluid-structure coupled method was employed to solve the nonlinear aeroelasticity problem for the *** computational results of the viscous flow are in good agreement with the experimental *** simulation on the aeroelastic behavior of the airship in a trimmed flight reveals the effect of structure flexibility on the aerodynamic performance.

关键词： fluid-structure interaction airship aeroelasticity flexibility

Performance Analysis of Two CFAR Detectors in Clutter Edge Situation

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Journal of Systems Engineering and Electronics 2001年第2期12卷 44-51页

作者： He You Department of Electronic Engineering, naval Aeronautical Engineering Academy Yantai 264001, P. R. China Guan Jian Department of Electronic Engineering, Tsinghua University, Beijing 100084, R R. China Department of Electronic Engineering Naval Aeronautical Engineering Academy Yantai 264001 P. R. China Department of Electronic Engineering Tsinghua University Beijing 100084 P. R. China

This paper studies the performance of the GOSGO and GOSSO CFAR detectors [1] in clutter edge situation. The authors derive the analytic expressions of the false alarm probabilities in that situation, analyze their performances against clutter edge, and compare them with the OS, CA, GO and SO detectors. The results show that GOSGO possesses better performance than GO for countering clutter, but the performance of GOSSO is very unideal.

关键词： Alarm systems Clutter (information theory) Gaussian noise (electronic) Signal to noise ratio White noise

Investigations of influence of gas content in water to propeller cavitation noise

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Investigations of influence of gas content in water to prope...

MELINIKOV’S METHOD FOR NON-LINER ROLLING MOTIONS OF A FLOODED SHIP

2009中国控制与决策会议

作者： ZHANG Yong-kun,XIONG Ying Dept.of naval Architecture & Ocean Engineering,naval Univ.of Engineering,Wuhan 430033,China

Radiation noise of ship propeller model has been measured for investigating the influence of gas content in the water to propeller cavitation *** results of experimental investigations clearly show that if gas content is kept invariable,the total noise becomes loud as ship velocity increases;if ship velocity is a constant,the total noise decreases while gas content in water increases.

关键词： propeller cavitation noise circulating water channel

来源： cnki会议评论

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Journal of Hydrodynamics 2005年第5期 64-68页

作者： PU Jin-yun, ZHANG Wei-kang, JIN Tao, JI GangCollege of Ship and Power, University of naval Engineering, Wuhan 430033, China

To investigate the rolling motions of a flooded ship, non-linear coupled dynamics of roll and flooded water are derived using Lagrange’s principle. Decoupling the coupled equations gives a single-freedom ordinary differential equation, which can describe the rolling motion of the flooded ship. Melinkov’s method is used to predict the chaos behavior of the ship. Numerical computations are performed for three statuses of a ship model. The comparison of the results shows that the more cabins flooded, the more likely a chaos phenomenon will appear.

关键词： ship flooding roll Melinikov’method