Title

Author

Abstract

A Novel Project on Radio Frequency Simulation System of Airborne Radar

LIU Feng, MAO Ji-zhi, XU Jia-dong

On past research on airborne radar simulation, a series of difficulties are encountered because the size of the requested microwave anechoic chamber under the far-field condition is too big with the current methods. The novel project presented in this paper will show how to deal effectively with these difficulties. On section 2 and 3, it is discussed in detail about how to reduce the size of the microwave anechoic chamber, while the bigger field-of-view, the better quiet region and the simpler control can be got. The analysis of the target positioning error is also presented in section 4

Modeling and Simulation Research on Advanced Short Takeoff and Vertical Landing Aircraft

WANG Jian, WANG Fei-yue, WANG Jia-xin, GUO Suo-feng

To realize the flight/propulsion integrated control technology for advanced short takeoff and vertical landing(ASTOVL), large amount of theory research and their simulation computation must be done to design the optimal control law. The flight space states of this kind of aircraft, depending on the syncretic control technology of aerodynamics rudder and thrust vector, are described in the entire quantity non-linear equation, and six-degree- of-freedom mathematical model of the aircraft dynamics is established. Since the aircraft mathematical model with rigid body characteristics and aerodynamics data are not dealt with linearly, the established model not only reflects roundly the practice characteristics of short takeoff and vertical landing(STOVL) aircraft, but also takes on general qualities. At last, based on the background of some type of STOVL aircraft, the flight digital emluator is studied and developed under the environment of MATLAB5.2/Simulink, and the designing ideas and program framework on the simulation software are introduced. As a result, the R&D flight digital emluator is correctly validated by the digital simulation.

The Research of Digital Integrated Simulation System of Micro-satellites

ZHANG Shan, BEI Chao, YANG Jia-wei

With the development of modern micro-satellites technology, advanced simulation technology is urgently needed in the system design and application simulation of micro-satellites. In this paper, based on the idea of collaborative simulation, the foundational scheme of simulation system is presented firstly. And then the architecture, the hardware configuration, the software system, and the corresponding key points are introduced separately. Finally, a primary experimental example to meet the requirement of mission simulation is presented.

Objected-Oriented Analysis and Implementation of Sea-Air War Gaming

JIANG Jun, LI Zhong, LIU zhong, CHU Jun-tian

Based on the tactical background of a sea-air combat, and by combining the Object-Oriented modeling technique with database technique, the process of modeling and implementation of VC++ is introduced. AAW (Air-Air War) program process is described, too. The mathematic theory of model is based on Monte-Carlo method. Some key objects’ method or function are expatiated. Simulation of a scenario is executed and the result is analyzed finally.

The Simulation Model and Algorithm of Synchronous Digital Hierarchy Fiber Communication System

XIANG Liang-jun, ZHENG Lin-hua, HAN Fang-jing

The key problem of synchronous digital hierarchy fiber communication simulation system is to set up the simulation model and simulation algorithm. In this paper, a modeling method and its model example of the general SDH equipment simulation system are proposed, and the related realization based on this model is also presented; The structure of this model also holds true for other communication system.

Passive Underwater Target Motion Analysis Based Upon Bearing-Elevation Measurement in Three Dimensions

HU You-feng, JIAO Bing-li

The problem of underwater passive TMA in the case of three dimensions, which uses the measurement of passive bearings-elevation, is discussed in this paper. The parameters estimations are gained using the method of PLE-Kalman, MLE and EKF in constant known depth in three dimensions. Then CRB (Cramer-Rao lower bound) is given in this paper. Finally simulations illustrate the efficiency of TMA proposed here. The TMA method can be come true in practice.

Simulation of Complicated Error and Its application

YI Dong-yun, WANG Zheng-ming, TONG Li

The paper presents the mathematic modeling of complicated error by optimal knot spline function, which can automatically separate not only the error with secondary low frequency but also the stochastic error from complicated error data. The simulation of the error with secondary low frequency is carried out by statistics modeling of spline parameters, the stochastic error by autoregressive modeling, and at last the simulation of the complicated error is integrated. As an application, the precision of data fusion processing system is discussed by including the complicated error

Comprehensive Modeling in Industrial Moisture Process System based on Extension Theory

LU Rong-de, CHEN Zong-hai

The comprehensive modeling in the industrial moisture process system (IMPS) is described in detail in this paper. We have built the model in the industrial moisture process system(IMPS), which is Discrete Time System on a longtime delay, large flow, large scale nonlinear with the method of that the three types of model such as mathematical mechanism model, experiment model and extension neural network model for rhombus-thinking process are intergrated into matter element extension model. Resolvent of mathematical model becomes beginning point, experiment model becomes overall regulator, and extension neural network model becomes regional regulator. These methods have clear physical mechanism, and can not only obtain large scale optimization results, but also resolve abnormal state structure problems. Simulation results demonstrate that it is effective, and that extension engineering methods about problem of complex industrial process system are valuable to an extended way.

Identification and Modeling of the Pneumatic System of the Mechanical Press

ZHAO Hong, LIN Ting-qi, ZHAO Sheng-dun

A new computer control system of the pneumatic friction clutch and brake in mechanical press is proposed. The pneumatic friction clutch and brake system is identified in the test. On the basis of analyzing the system, normal model structure, error predictive method and the experimental model of the pneumatic system are presented. By comparing the results of identification with the test data, the creditability of the model is proved. A perfect model of the pneumatic friction clutch and brake system is obtained. The model not only well reflects the dynamic characteristics of the system but also can help the system controller design

A Platform for Validation of air-to-air Missile System Simulation Model

WANG Jian-hua, FU Wen-xing, YAN Jie

A platform for validation of air-to-air missile system simulation model is introduced in this paper. The generally used statistical test methods which are employed in evaluating simulation model validity in engineering are integrated in the platform, and the platform has an open architecture and high extensibility. Finally we use an example to demonstrate how the plotform works.

VPRS Model Approach to Fault Feature Selection and Diagnostic Rules Extraction

ZHANG Deng-feng, WANG Zhi-quan

A method based on VPRS(Variable Precision Rough Set) model theory is proposed to fault features selection and diagnostic rules extraction in engineering systems. The approach is realized by selecting proper classificatory error parameter b and using knowledge reduction. It can not only extract effectively the optimal fault features, but also find the simplest diagnostic rules for the system. Simulation results for rolling bearings show that the method improves the rate of fault diagnosis, decreases the number of feature parameters and diagnostic rules, and reduces the cost of diagnosis, with more applicability than the classical RS-method in practical applications.

The Automatic Modeling of Complex Functions Based on Genetic Programming

ZHOU Ai-min, CAO Hong-qing, KANG Li-shan, HUANG Yu-zhen

In this paper, we apply Genetic Programming to the automatic modeling of complex functions. In our programs the complex functions are expressed by multi-layer trees. The Genetic Operators such as Crossover and Mutation, Termination Conditions are designed respectively. Further more, we give two examples, whose results show that the models set up by Genetic Programming are better than the models set up by classical algorithms, and even better than some models designed by specialists.

A Reformative Multiple Model Approach to Noise Identification

ZHU Hong-yan, HAN Hong, HAN Chong-zhao, ZHAO Guang-she

The interactive multiple model algorithm (IMM) is an effective solution to the hybrid estimation problem. The model set augments along with system behavior patterns increase. A reformative multiple model approach is presented to improve the accuracy of parameter estimation when the model set is too large, and it is used to identify system noise. By means of the multiple scans of measurements information and the discrete optimization technique, the optimal sub-model set can be obtained which is close to the real noise level of the system. The final output is obtained by using it. The simulation results indicate that the new algorithm is better than the standard IMM

A New Method Based on Density Clustering for Discretization of Continuous Attributes

LI Xing-sheng, LI De-yi

Discretization of continuous attributes is one of the important steps in preprocessing of data analysis. In this paper, a new method of supervised discretization of continuous attributes based on clustering is introduced. This method makes use of the concept of the level of consistency of decision table in Rough Sets. By computing the level of consistency of the produced decision table, the coefficient of clustering, influence factor, is adjusted dynamically. And this procedure couldn’t stop until the level of consistency of the decision table reaches its original level. Because the discretization of all continuous attributes is done simultaneously, the result should be reasonable. Experiments show that this method is feasible.

The GP-Stability of the New Block q -Methods for the Neutral Differential Equations with Pantograph Delays

CAO Wan-rong, ZHAO Jing-jun, LIU Ming-zhu

The block methods are superior to the generally numerical methods because of its preferable process of computation and stability. Based on the new q -methods, the new block q -methods are given and applied to the neutral differential equations with pantograph delays. By studying the numerical solutions of difference equations and its petured equations, the sufficient conditions of GP-stability of the new block q -methods are established

The ANN Evolutionary Design Method Based on Species Evolutionary Genetic Algorithms

LI Zhi-yong, TONG Tiao-sheng

Aiming at the question of design for ANN's architecture and the drawbacks of normal design methods, it is proposed in this paper the species evolutionary genetic algorithms (SEGA) as well as a new method of designing ANN's architecture based on SEGA by the example of MLP. This method, by combining neural network (NN) and genetic algorithms (GA), has the superiority of ANN's modeling efficiency and fitness in application. The simulation and application have demonstrated that this method is effective.

Dynamic Process Simulation for the Safing Control System on the Missile

LU Yuan, SHENG Wen-jing

The safing control system on the missile is a process control system driven by discrete events. To meet the requirements of dynamic process simulation for evaluating the system safety, a modeling and simulation method based on MATLAB has been developed. This paper describes how to make an abstract of the safing control structure, build a virtual system instead of the real system, design virtual flights instead of real flights，and simulate the safing control process and system faults. In this paper, the safing control structure, the virtual system model, and the results of dynamic process simulation and faults simulation are given.

Modeling Proton Exchange Membrane Fuel Cell (PEMFC) Based on Neural Networks Identification

WEI Dong, CAO Guang-yi, ZHU Xin-jian

For the serious complexity of Proton Exchange Membrane Fuel cells (PEMFC), modeling of it is very difficult and the existing models are too complicated to be applied in designing and controlling of the system, especially in on-line controlling. In this paper, we try to establish the voltage and current model of PEMFC by using neural networks identification technique. The operating temperature of the fuel cells is taken as the input and the voltage and current response as the output of the neural networks model. In this way, we can avoid the internal complexity of PEMFC. The 500 groups experimental data are used, and the structure and the novel BP algorithm of neural networks identification system are given. The validity and accuracy of the model are proved by the simulation results. The neural networks modeling makes it possible to design on-line controller of PEMFC.

Inference Engine Designed for Real-time  Monitor and Launching Decision-making Expert System

WANG Bing, MO Jian-jun, WANG Yu-ying

Real-time monitor and launching decision-making expert system carries through knowledge inference, judgement and final missile launching according to monitor information. The paper introduces the design criteria, inference controlling strategies and running process. The inference engine combines both object-oriented method and Blackboard model. It makes the knowledge base layered and modularized, and greatly raises the infer efficiency. The inference engine has features of distinct structure, clear consecution, and convenient maintenance

Simulation Study of a New Method to Synchronously Control Rotate Speed and Power of a Steam Turbine

SHI Xiao-ping, WANG Zi-cai

The frequency of the electric network will inevitably fluctuate because of rotate speed variation of a steam turbine, while its classical regulation system is accomplishing matching between its power and the referenced electric load. A new method is developed to synchronously control rotate speed and power of a steam turbine with pole placement technique of linear system. With this new control method, not only the rotate speed of a steam turbine can be controlled according to its instruction curve, but also its power can be synchronously controlled to quickly track the electric load without additional component of the frequency regulation. The computer simulation verifies the correctness and the effectiveness of the presented new control method.

Study and Simulation of Manipulator Kinematic Solution at Singular Configurations

HU Zhun-qing, FANG Hai-rong, FANG Yue-fa

A new approach to the singularity analysis of manipulators is presented. The joint axis linear dependence is determined by using classified line varieties, so that not only the singular configurations of the manipulator can be identified but also the specific axes becoming linearly dependent can be recognized. The task space feasible motions are identified by using reciprocal screws. By isolating the linear dependent columns and rows in the Jacobian matrix, the corresponding singular Jacobian matrix is simplified from 6×6 to 5×5, so that the exact solutions for the manipulator are obtained near singular configurations. In the end, some simulation results for PUMA manipulator are given to demonstrate the effectiveness of this method.

A Simulation Study on Load Preview PredictiveControl of A Thermal Power Plant

WANG Dong-feng, HAN Pu, WANG Guo-yu

In view of the existance of frequently loading increase/decrese and many disturbances in unit power plant, based on the resource of Automatic Generation Control(AGC), a preview predictive control strategy is proposed for load control system. The new method is constructed by the kernel algorithm of multivariable predictive control, with preview control calculated off-line as a feed-forward signal, and the idea of preview control is fused into predictive control. Then a novel load coordinated control system is contributed. The computation simulation results show that the new strategy has the merit of preview control and predictive control It makes that the load has good tracking property, main steam pressure gets better dynamic and static characteristics, and control input value is very smooth also.Very strong robust performance is obtained while dynamic property of the controlled plant varies in a wide range

A New TCP Congestion Control Mechanism for Differentiated Services

LI Fang-min, ZHOU Zu-de, PENG Xiao-bing, LI Ren-fa

Differentiated services can provide different QoS for different user demands. TCP plays an important role in the Internet, but TCP’s window-based congestion control algorithm impairs long RTT connections to achieve fair bandwidth share and support differentiated services, so researches on TCP congestion control for differentiated services is a meaningful job. This paper presents an active queue mechanism, EBLUE, and improves TCP congestion control algorithm. Then by combining two technologies, we investigate how TCP supports assured service and achieves fair bandwidth share among connections. The simulation results testify that our mechanism is feasible and fair

Simulation Studies on Ship Controlling Based upon Simulink Tools

LIN Ye-jin, REN Guang

A Simulink version of Abkowitz nonlinear ship kinetic model is created with the use of Matlab S-function after a prior introduction of the modeling method of ships in 3 degrees of freedom, and the results of simulation studies on ship controlling based upon the Simulink model are presented. It is aimed to be beneficial for performance tests of ship manoeuvrering and studies of ship control strategies.

Enhance the Measure Acuracy of Radar Altimeter through Echo Simulation

YANG Wen-xia, ZHANG Yun-yu, HU Xiu-lin

This paper introduces a model of wide-beam radar video echo simulation and the process of simulation, and gives a detailed calculation of all the parameters in this model. Through a large scale of calculated echo according to the terrain, a rough statistical rule of echo related to different terrain characters is achieved, which is used to rectify the height measurement’s accuracy of radar altimeter, and the rectified results are also presented at the end of the paper.

Research of Different Dimension Process in One Centralized Multi-radar System

XIONG Wei, HE You

In one centralized multi-radar tracking system, there are always different radars, which may have different observation-dimension. In order to correctly fusion all data of radars, the system must take some measures to make suer that all data have uniform dimension. At present, reducing dimension is often used to deal with the problem. Because of the loss of the height information of target in the process of reducing dimension, the system may produce some dynamic error. If the pitching angle of target is relatively large, the tracking precise of the system must be reduced. In this paper, one increasing dimension method is introduced, which can be used to remedy the defect of reducing dimension method. At last, a Monte Carlo simulation is used to analyze the tracking precision of the two methods.

Response Simulation of Non-Obstructive Particle Damping Structure Based on Extremal Properties of Endochronic Theory

WANG Wei, HUANG Xie-qing, CHEN Tian-ning

Non-Obstructive Particle Damping (NOPD) is a new composite damping technology which is based on traditional particle damping and impact damping technique. NOPD technology is applicable to awful circumstance and has good effect on vibration absorption. In the paper the response of NOPD structure is analyzed by endochronic theory which is simplified by extremal properties. Computer simulation and experiment are done on the basis of it. Results show it feasible to calculate the response of NOPD structure by simplified endochronic theory, which afford an effective analysis method for engineering application of NOPD technique

Simulation Study of Cascade Predictive Functional Control for AC Servo System

PAN Hong-hua, HU Jia-sheng, WANG Jian-ming, WANG De-hu  

Three cascaded close-loop control applied to AC Servo-system is studied according to the principles of predictive functional control. Based on its closed-loop performances analyzed, the method to design the predictive functional controller is given. It sets up the structure of three cascaded close-loop predictive functional control system applied to AC Servo-system. The implementing method of cascaded control is discussed. The simulation results and the comparison with PID method show that the predictive functional control can improve controlled performances of AC Servo-system.

Research on XML Modeling of Design Information in Die CAD System

WANG-Jun, LIU-XiaoPing, YU-ShiGuang

Traditional organizing way of the die design has many problems in cooperating design. Feature-based press tool Schema dictionary is designed based on the XML data model in this paper. Press tool design document is organized through the XML document, which supports the cooperative design of the press tool efficiently, solves the problem of the information transfer among the designers, and supports information modeling facing the product life cycle.

The Application of Software Defined Radio on General Radar Signal Processor

CAO Ning-sheng

The concept of Software Defined Radio is firstly developed based on communication requirement and also used in the communication field. However, the new design idea is fully the same with other fields, for example, radar, sonar and so on. In this paper the basic principles and key techniques of SDR are introduced. In allusion to the peculiarity of co-herent radar, we present a method that radar signal  is sampled in intermediate frequency. It not only provides better reliability and rate of signal and noise, but also improves phase noise and spurious. SDR technique and correlative products are used to construct a general radar signal processor. Finally, the system performance is analysed.

Dynamics Simulation of A Network Routing Algorithm Based on NS-2 Network Simulator

FU Yun, ZHENG Nan-ning, XU Wei-pu

NS-2(Network Simulator V.2) is a discrete event simulator targeted at networking research. The main C++ classes of NS-2, LANs simulation, unicast, network dynamics and routing strategies are described. The Distance Vector(DV) routing which is the implementation of the Distributed Bellman-Ford algorithm is discussed, and concluded with a description of the internals, architecture and interface between unicast routing and network dynamics. An experiment for a 7-node dynamic network of token ring, where the routing adjusts to a link failure, has been designed. Nam and Xgraph tools yield the animation of the packets communication, and create graphic representations of simulation results. The experimental results show that the DV routing can prevent temporary violations of causality, such as packet reordering, around the instant that the topology changes. The difference between theoretical and the actual amount bytes received is caused by the amount of dropped packets, lost packets and the real interference parameters.

Application Study of the Dynamic Simulating Model in Vehicle traveling

CHAI Yi, SUN Yue, HUANG Xi-yue, GUO Mao-yun

Aimed at the issues on the active safety system of intelligent automobile such as safety-modeling and real-time solution, automobile’s safe-traveling is actually perception (detection) and processing (steering) in time, which is based on the important factors during the automobile’s traveling; the speed and distance between automobiles. In the paper, the perception and operation in time for automobile safe-traveling are represented by variable of time related to speed. Also, P²OT (perception, policy, operation, Traveling) and its expression of time are introduced in the paper. The results of the analyses and experiments show that the methods discussed in the paper are feasible and valuable practically

Improvement on Terminal Demonstration in Decoy Simulation System and Relative Discussing

LUO Xiu-bo, DONG Yang-ze, LIU Ping-xiang

In this paper, the Decoy Simulation System(DSS) is introduced, the effects caused by the DSS in the Terminal Demonstration Platform based on Multigen&Vega is expatiated. To meet the effects, the original program of demo based on Vega in Terminal Demonstration Platform is improved by using the technique of multi-process, share memory and Lagrange interpolation, and good result is achieved.

Research of the Distributed Simulation Based on MATRIXx

SUN Zhi-xin, WANG Ru-chuan, WANG Shao-di

We report on a universal real-time visual distributed simulation system based on MATRIXx. The MATRIXx is used as a development platform. The system can receive different input data, which may come from network or local terminal. Application models in the simulation modules can get such data automatically to analyze and calculate, and then produce real-time simulation control information. The information can be transmitted to the rendering driven modules through special data server. And the rendering driven modules can employ the simulation information to drive different 3D model in a real-time. For this purpose, the corresponding software interfaces have been developed to integrate the whole system. Meanwhile, we have designed relevant simulation components to implement the input data and output data, which can guarantee the real-time and universal of the data transmitting. The system can be used in airplane flight training, airfight training, motor drive training and ship drive training etc

Test and Evaluation Technology of C³I System Based on Simulation

WANG Si-hong, MAO Shao-jie

Performance test and evaluation of C³I system has always been a challenge. In this paper, a method of C³I system evaluation based on simulation is proposed. The basic configuration and supporting technology of the C³I system simulation environment are presented, and they are verified by testing of an example.

The Concept and Characteristics of a Distributed Simulator for Fuel-fired Power Plant System

ZHANG Wei-wei, CHENG Fang-zhen

A new distributed concept about the simulator for fuel-fired power plant system with DCS is proposed in this paper. This new type of simulator is based on the software system of the Xinhua’s XDPS-400 distributed control system and the Windows-based simulation supporting in China. The characteristics of the simulator are discussed and the compared dominance with the traditional centralized simulator is analyzed.

Application of Database Technology in the Dynamic Virtual Prototype

LI Ni, LIU Jie, PENG Xiao-yuan

The paper presents the Collaborative Modeling/ Simulation Architecture of Dynamic virtual prototype of aero craft, and Distributed Database of Client/Server Architecture is adopted to manage models and data. The basic function of Model Management System is realized with focus on Model Dictionary. The database is accessed and manipulated by ActiveX Data Object, and Client Application Program for the sub-systems of Dynamic VP has been developed to complete the data interaction with Modelbase and Database. The application of database technology in the Collaborative Simulation Environment is also briefly described.

Research on Key Technologies for Virtual Environment Oriented Scene Management and Their Implementation

 LUO Zi-rong, CHANG Ming, XIAO Ren-bin

In this paper, several key technologies on virtual environment oriented scene management and their implementation are addressed. Adopting the strategy of managing and rendering scene respectively, a new scene graph that can effectively describe large-scale virtual environment and a Scene graph based Binary Space Partition tree (SBSP) are proposed. Multiple thread technology based portal is used to load universe at real time according to the motion of avatar, and this method can avoid complex multiple thread control and communication of traditional scene schedule means. Based on above techniques, a prototype system named InteVR 1.0 has been developed, which uses OpenGL as graphic interface, to support the scene management and real time navigation of large-scale virtual environment.

A Fast Algorithm For Panoramic mosaicing

ZHANG Han-ling, HAO Chong-yang, ZHANG Min-gui, LIU Qing-yun

A new robustness algorithm is presented for automated panoramic mosaicing based on multiresolution spline technique. First, an iterative nonlinear minimization algorithm is presented based the Levenberg-Marquardt algorithm; Second, an image registration algorithm is presented based on multiresolution spline technique ; in the procedure , the images are blended with different weighted functions in each frequency band. The coefficients of the weight function and the length of the transition zone are decided by the difference scale of the two images to be stitched in each frequency band . The algorithm can be finished with automating in most cases and suit for any scale image with any unknown parameter of camera (such for focal length).

Design and Implementation of a Virtual Operation System for Beautifying Lady’s Face

ZOU Bei-ji, LV Ge-feng, ZHOU Hao-yu, SUN Jia-guang

We have developed a virtual operation system for beautifying lady’s face, which is called as ByuPAQ. By using it, a lady can see her beautified-face image in advance to decide how to apply the surgical operation to her face. A lady’s face picture is firstly inputted into the system ByuPAQ, then some operations provided by the system ByuPAQ are applied to it interactively, and finally the beautified-face image will be displayed. In this paper, we firstly introduce the architecture of the ByuPAQ, and then we show the principles of designing the system ByuPAQ and describe two key algorithms. One is image deformation algorithm, and the other is image shading algorithm. At last some examples resulted from the system ByuPAQ are shown.

A Method and Numerical Simulated Study on the Non-Newtonian Lubrication for Journal Bearing

FU Yan-li, YANG Pei-ran, ZHU Jun

Taking power law fluid as an example, a method of solving the non-Newtonian lubrication in journal bearing is introduced. By using this method, the Reynolds equations of Newton fluid and non-Newtonian fluid are unified by defining two equivalent viscosities, avoiding to deduct different Reynolds equations for different type non-Newtonian fluids. Furthermore, the effects of the power law index on the lubrication performances are analyzed by numerical simulation. It is found that the power law index has no effect on the film thickness and has slight effect on the film pressure when the temperature change in the oil film is not considered, but it significantly affects the film thickness, pressure and temperature when the three dimensional temperature in the oil film is considered.