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1998 Vol. 24, No. 3

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Research of Modificating Unsaturated Polyester Resinby Copolymerizing Bismaleimide
Zhang Fusheng, Zhuang Yan
1998, 24(3): 249-252.
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The modification of an unsaturated polyester(UP) resin by copolymering a second co-reactive monomer as thermosetting bismaleimide(BMI) was studied. The resulting inter-crosslinked network showed an obvious enchancement of the glass transition temperature ,elastic modulus and strength. FTIR is used t...
Study on Microstructure and Aabrasive Resistance of Laser Cladding TiN Surface Alloyed TC9
Chen Chinan, Su Mei
1998, 24(3): 253-255.
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Laser surface cladding with TiN is utilized to improve the wear resistance of TC9 titanium alloy. Microstructure and phase constitution are studied by using SEM, EDX and XRD. Microhardness measurements and wear experiments without lubrication are performed to test the properties. The experimental re...
Computation of Electromagnetic Scattering Character fromComplicated Object Partially Coated with RAM
Li Jianhui, Su Donglin, Li Qing, Lü Shanwei
1998, 24(3): 256-259.
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The general formulas of the scattering field when the parallel and vertical polarization plane wave incident on the objects are given.The method of determining the strong scattering source of complex objects,and the effective method of selecting region coated with radar absorbing material(RAM) are p...
Scattering Character from Perfectly Conducting Cylinder Coated with Plasma
Huang Xingzhong, Lü Shanwei
1998, 24(3): 260-262.
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The general formulas of the scattering field and scattering parameter definition when the parallel and vertical polarization plane wave respectively incident on the cylinder are given.The radar scattering cross section(RCS) of the metal cylinder coated with undensed plasma,densed plasma and loss mat...
GPS Positioning Algorithm Based on Least Square Recurrence Estimate
Chang Qing, Liu Zhongkan, Zhang Qishan
1998, 24(3): 263-266.
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This paper proves,in theory,that GDOP decreases as the number of satellite increases.Then the recurrence algorithm of GDOP and positioning solution is proposed based on the existing positioning software.This algorithm chooses the fifth satellite which enables GDOP5 to be minimized from the surplus v...
Method to Improve Performance of Estimation of DOA Using Toeplitz Characteristic
Si Deyi, Le Qiang, Shen Shituan
1998, 24(3): 267-269.
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A method is proposed to make the estimation of the covariance become Toeplitz matrix using the Toeplitz characteristic of covariance matrix . It can improve the performance of estimation of DOA in the low SNR and shot snapshot , and dose not add complex multiplication. It is used in the MUSIC algori...
CGF Terrain Representation and Reasoning with Contour Map
Wang Changjin, Le Ningning, Wang Xingren
1998, 24(3): 270-273.
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A digital contour map is used for terrain representation of Computer Generated Forces(CGF) in Distributed Interactive Simulation(DIS).The method of contourline terrain representation and reasoning is presented.After discussing the determination of terrain and intervisibility,and etc.,it is shown tha...
Calculation of Mission Reliability of Fault-Tolerant Standby Storage System
Jin Hong, Zhang Hongyue, Li Peiqiong
1998, 24(3): 274-276.
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The calculation of the mission reliability of a fault-tolerant standby storage system is discussed.Whether the fault detector,switch and the standby component are reliable or not affect the reliability of the fault-tolerant system directly.In order to evaluate its mission reliability correctly,the d...
Method of Conditional Filtering for Stochastic System with Distributed Parameters
Wu Sentang
1998, 24(3): 277-278.
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In the case of the stochastic system with distributed parameters exist observation noise in its control input and its control output, the conditional filtering method of the stochastie system with distributed parameters is presented.While the optimum estimation of system state is obtained, the optim...
Design and Simulation of Integrated Flight/Vectored Thrust Control System
Shen Gongzhang, Hao Jiankang, Peng Kemao, Zhang Minglian
1998, 24(3): 279-282.
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The design of the flight control system with the vectored thrust is discussed. The flight state variables are separated into the fast and the slow state variables based on their transient responses. Nonlinear dynamic inversion is adopted to design them separately. The simulations of the flight of th...
Design of Integrated Flight/Vectored Nozzle Control System at Take-Off
Peng Kemao, Shen Gongzhang, Wen Chuanyuan
1998, 24(3): 283-286.
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Four kind of configurations are adopted to analyze the improvement of the vectored nozzle control on the flight performances at take-off,where the baseline aircraft is modified to add the horizontal canard or/and vectored nozzle. The models of the aircraft longitudinal motion at the different progre...
DR Algorithms and Parameter Estimating in DIS System
Gong Guanghong, Wang Xingren
1998, 24(3): 287-290.
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A method of position/orientation estimation called dead reckoning methodology has been playing an important role in DIS system,which is employed to simulate synthetic warfare environment simulation and military training exercise containing multi-force and multi-platform. First,common DR algorithms a...
Fuzzy Adaptive Controller Based on BP Algorithm
Zhou Changyu, Wang Wenshun
1998, 24(3): 291-294.
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When we apply fuzzy control to a unknow process,we can't find good control rule because of we don't know it's characteristics.This paper based on an analytic structure of fuzzy controller put forward a method,which combines fuzzy controller and neural network.Use neural network to make identificatio...
Analysis Failures on Attenuating Vibration of Squeeze Film Damper
Liu Fangjie
1998, 24(3): 295-300.
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The meaning of study the failure of attenuating vibration of the squeeze film damper is detailed.First,the achievement in scientific research accomplished by J.W.Lund,E.J.Hahn,R.Holmes,R.A.Cookson and E.J.Gunter five academic groups for study the squeeze film damper in international is compendiously...
Mathematical Analysis on Combat Efficiency of Military Aircraft
Wang Yinsheng, Wu Zhe
1998, 24(3): 301-303.
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The mathematical methods of theoretical analysis to determine some unknown or omitted parameters in combat efficiency theory of military aircraft based on the present models of combat efficiency of airforce equipment and the actual data of military operation are introduced in order to develop or imp...
Optimization Aerodynamic Design for Transonic Airfoil
Yan Chao, Xie Lei, Li Yunxiao
1998, 24(3): 304-307.
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Computational Fluid Dynamics(CFD) and optimization technique are combined in this paper for the purpose of optimal aerodynamic design of transonic airfoil. In this method, 2-D Euler equations are numerically solved to simulate the flow around airfoil using finite volume method, then geometric condit...
Correlative Parameter Estimated Method in Random Process of Fatigue Crack Propagation
Zhang Jianyu, Fei Binjun
1998, 24(3): 308-310.
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Lognormal random process model of fatigue crack propagation is usually used in the reliability and damage tolerance analysis.Basing on the model, a new method of evaluating the auto correlative parameter in usual stationary normal random process by the experimental data is established.By using this ...
Effects of Vortex Generators on Maximum Lift and StallAngle of Attack over Wings
Shen Xialing, Gao Ge, Liu Baojie, Yang Xiaoning
1998, 24(3): 311-314.
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The effects of locations and various cambers of small delta vortex generators on the maximum lift and stall angle of attack of wings are studied in the wind tunnel.The small delta vortex generators varied in cambers and locations are fixed on the wing model which has NACA 0012 of span 500 mm chord 2...
Numerical Simulation and Optimization for Contraction Flow of Water Tunnel
Wu Zongcheng, Chen Yanqing, Wan Xi
1998, 24(3): 315-318.
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A numerical method and computer program for non-symmetrical contraction flow of a water tunnel are described in this paper, which use the finite volume approach to solve the unsteady Euler equation, the basic algorithm is the explicit predictor-corrector scheme of MacCormack. For several typical con...
Analytical Method of Solution on Delamination in Symmetrical Orthogonal Composite Laminated Beams
Wang Qizhi, Meng Qingchun, Zhang Xing
1998, 24(3): 319-322.
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Using the principle of superposition, the transverse loading state of a laminated beam with delaminations is divided into symmetric and antisymmetric states. Furthermore, the antisymmetric loading state is subdivided into the antisymmetric transverse loading state acting on a beam without delaminati...
Research on Design Principles to CAD/CAM Geometric Platform Based on STEP/AP203
Ren Aihua, Wei Juxia
1998, 24(3): 323-326.
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The approaches and the design principles to the CAD/CAM geometric platform based on shared standard semantic models of STEP/AP203 in the CIMS environment are expounded in this paper. STEP gives the possibility of developing software component architecture in terms of object-oriented technology. Ther...
Performance Gradient Estimation for M/G/1 Queueing System Using Nonstandard Analysis
Huang Hongxuan, Han Limin, Feng Yuncheng
1998, 24(3): 327-330.
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Estimating performance gradient is an important issue in the study of Discrete Event Dynamic Systems(DEDS). Because of discontinuous sample path, it is difficult to estimate performance gradient with respect to probability parameters by traditional perturbation analysis.A new kind of algorithm, whic...
Some Issues about Information System Integration
Liu Lu, Zhang Zhaohui, Yao Zhong
1998, 24(3): 331-335.
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Several issues in the information system integration are discussed,such as information integration,function integration,platform integration and human integration etc..A multiphase-based methodology for information system integration is presented,in which the integration is the goal of the system in...
Effective Measurement in Project Cost and Schedule Control
Wang Liwen
1998, 24(3): 336-338.
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Earned Value is the most important measurement in the project cost and schedule control. This paper describes the concept and methods of earned value,and its application in the project cost and schedule control. Then, this paper tells how to forecast the likely cost to complete the project,and intru...
Kinematic Inverse Problem and Stability of Wheeled Mobile Robots
Lu Zhen, Yan Biao
1998, 24(3): 339-341.
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Mobile robot can be regarded as the combination of a manipulator and a walking machine.It has more manoeuvrable and larger working-space.Thus,it is suitable for long-range operation both in the space and the ground.The most common used mobile robots are wheeled mobile robots(WMR).The wheeles lead to...
Accuracy Analysis of Micromanipulator
Bi Shusheng, Zong Guanghua
1998, 24(3): 342-345.
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Two types mechanism of micromanipulator appeared in recent years. It is the serial mechanism and the parallel mechanism. They possess their respective strong and weak points. Based on the complementary law, one new type which is called Serial-parallel Mechanism is presented in this paper. In order t...
Coordinate Transformation and Effective Velocity for One Class of Hydrodynamic Sliding Bearing
Yan Deyuan, Guo Jingjing, Zhang Xiaohong
1998, 24(3): 346-349.
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The differential equations of pressure for two moving surfaces hydrodynamic sliding bearing are deduced by transforming coordinate transformation method, and the concept of effective velocity is introduced. Then a simple and convenient method for engineering design of this bearing is presented. In c...
Active Back-propagation Algorithm Based on Adjusting Error for Multilayer Feed-forward Neural Network
Luo Dehan, Chen Weihai
1998, 24(3): 350-353.
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The back-propagation (BP) algorithm was used as a learning algorithm in training multilayer feed-forward neural networks (MLFNN) in past years, and some improved BP algorithms have recently been developed to speed up MLFNN learning. However, the effeciency of these improved BP algorithms are limited...
Structure Design for 7-DOF BUAA-RR Manipulator
Qian Xikang
1998, 24(3): 354-357.
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In order to avoid obstacles in task space, overcome interior singularities and improve the performance of manipulators, redundant manipulators have been thoroughly researched and developed. In the process of designing BUAA-RR 7 degrees of freedom, a complete set of principles and methods are propose...
General Development Shell for Fault Diagnostic Expert System
Zhao Tingdi
1998, 24(3): 358-361.
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FDEST—The general development shell for non-real Fault Diagnostic Expert Systems(FDES) based on the reliability analysis methods is introduced in this paper,there are strong inference and good openness,it can apply to establish FDES for varied military materiel and civilian products.At first,the str...
Research on Comprehensive Application of System Engineering with Quality Function Deployment
Yang Duoming, Ruan Lian
1998, 24(3): 362-364.
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It is presented here that the idea on comprehensive application of System Engineering and Quality Function Deployment. A standardizing and programmable method is developed for determining requirements, making trade-off and finally, implementing these requirements, by means of System Engineering's fu...
Preliminary Study on Arcjet
Liu Yu, Zhang Zhenpeng, Wu Hanji, Feng Xuezhang
1998, 24(3): 365-368.
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The two-dimensional axisymmetric subsonic-transonic-supersonic flow in an experimental arcjet thruster is simulated numerically using flux vector splitting method.The profiles of density,velocity,temperature,pressure and Mach number can be obtained by the computation.The computation grid and some co...
Numerical Simulation of Gas Mixing in Cross-flow
Xu Xu, Zhang Zhenpeng
1998, 24(3): 369-372.
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A time-split explicit TVD MacCormack algorithm is used to solve the two-dimensional N-S equations coupled with species diffusion equations.Both molecular and turbulent properties of viscosity,thermal conductivity and mass conductivity are calculated.In order to deal with the near wall separation of ...

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