Title

Author

   Abstract

A Modeling and Simulation of Construction Closure for Transportation System Based on Timed-Petri Nets

SHU Hua-ying, HU Zhi-gen, LIU Quan

The layout of a transportation system influences the construction schedule and project success-failure directly. Based on that Petri nets are fit to describe transformations of the system form and state and that object-oriented technology is easy to construct interactive system, this paper establishes the model of Ⅲ-Phase Closure of TGP for transportation system using timed-Petri nets combined with object-oriented technology. The exertion of this simulation model and method optimizes the machine numbers of construction process and reflects transformations of the system state. The computational results illustrate that the simulation model and method are effective and feasible.

Five Key Issues of the Development of Simulation Systems VV&A

YANG Ming, ZHANG Bing, MA Ping, WANG Zi-cai

Simulation systems have become one of the essential and un-substitutable tools for both military and civilian production and research. The credibility of simulation is an important problem influencing the application of simulation technology to the more broad fields. The importance of simulation Verification, Validation and Accreditation (VV&A) has been realized and cared about by the simulation users, developers and project managers. In this paper, five key issues facing the development of simulation systems VV&A have been researched one by one. Some proposals to progress the VV&A in China are also presented.

Software Development for Simulating Biological Wastewater Treatment Processes

YUAN De-cheng, FAN Li-ping, YU Hai-bin

The software for computation of biological wastewater treatment processes is developed in terms of files published by Work Groups of International Association of Water (IWA). It can be applied to the simulation of dynamics of some plant’s layouts such as only-carbon removal, nitrifying, denitrifying nitrogen removal and combined phosphate and nitrogen removal, to the evaluation of the results of control strategies based on it, and to personnel training. The performances and effectiveness are demonstrated by computing the above configurations and by controlling the benchmark of denitrifying nitrogen removal.

The Implementation of the Real Time Products Demo Based on Web..............

YAN Xing-e, CAI Tao, XIN Yan, JU Shi-guang

First, this paper analyzes characteristics of some method introducing products existing in the Electric Commerce now, and then describes the key technologies and implementation of the real time products demo hall designed by authors. This demo hall can presents the real products to the customers, and the customers can browse the demo online by internet, control this demo by commanding the running of the pickup camera and control the function of the products by Internet as well.

Research on Virtual Exhibition System of Scene

WU Ya-dong, CAI Yong, HAN Yong-guo

Based on software platform, MultiGen Creator and Vega, the virtual exhibit system of scene has been developed, which integrates functions of roaming and designing. Firstly, the whole structure of this system is analyzed. Then, some key technologies are introduced, such as modeling method of scene, texture processing, format transforming and simplifying. Some programming technologies are also discussed, such as freedom degree controlling, colliding testing and input controlling, suggestive information showing, objects picking. The result shows that virtual exhibit system of scene could be widely used in building arrangement and exhibition. The prospect of this system in market is very well.

Design of Special Type Equipment Operation Training Simulator in Virtual Environment

HE Sheng-ping , QIN Zheng , LI Ai-guo

Inspect periodically in maintenance of STE (special type equipment) requires a lot of workforces with a high degree of technical skill in assembling and disassembling. In this study an operation training simulator in virtual environment used easily by novice users is researched. The control process diagram and information floor diagram of the system are provided, and some key technologies of this study are analyzed including geometric model based on assembly relation constraint and kinematics models management based on tools semantics constraint, VE manager designing based on environment semantics constraint, and operation haptic feedback simulating based on Cyberglove dataglove.

Real time Visual Simulation of Battlefield Environment of Foreshore

DONG Zhi-ming, GUO Qi-sheng, SONG Jing-hua, LI Qiao-li

Battlefield environment of foreshore is the main battlefield environment of landing battle. The paper researches the mathematic model and simulated model of ocean wave, realtime analysis of visual simulation, generation of terrain and generation of foreshore, the amphibious vehicle’s maritime motion attitude, the key technologies of BSP and multi channel, and applies them into the simulation of battlefield environment of foreshore.

Design of Multi-sensor Data Fusion Simulation Platform

LV Yan-mei, SHAN Gan-lin, SUN Jiang-sheng

Data fusion is the important composition part of modern C3I system, and plays a decisive role on the performance of C3I system. This paper simply describes the importance and practically significance of multi-sensor data fusion simulation platform, and introduces the construction of multi-sensor data fusion simulation platform. According to the necessary modules needed by location level, rationally the software is designed. The platform uses the structure of modularization and exoteric, and makes the platform own the characteristics of common use, real-time, dialogism and so on. At last, a software example running on the simulation platform has validates the reliability and practicability of the simulation platform.

Research on Cooperative Relation Model Based on Agent

ZHAO Ya-wei, ZHANG Hai-sheng

We provide and define a cooperative relation model based on analyzing cooperative relation among agents in cooperative environment. Temporal and special mechanism, which is use to describe dynamic cooperative procedure in cooperative environment in real world, is introduced in this model. An example in this paper demonstrates that using this model could solve some problems such as changing of cooperative relation and so forth.

Neural Networks Modeling of a Class of Process Control Object and Its Simulation Research

LI Min-yuan, DU Yan-li

A modeling method based on Neural Networks (NN) is proposed in this paper for the sake of tackling problems such as nonlinearity and parameter uncertainty in a typical process control system. The series-parallel identification structure is adopted to reflect characteristics of the control object well and truly. Furthermore, the improved BP (Back Propagation) algorithm and floating-point genetic algorithm are respectively employed to train the weights of networks. The simulation results show that the global searching ability and high efficiency of genetic algorithms have a marked effect not only on fast learning of the multi-layer forward neural networks, but also on stability of training. So, this method can be used in NN modeling and controlling as a good way of optimization.

Research on Multi-disciplinary Modeling Based on HLA

CHEN Xiao-bo, XIONG Guang-leng, GUO Bin, ZHANG He-ming

As there is the lack of multi-disciplinary modeling approach based on commercial simulation software, which is standard, open and scalable, the multi-disciplinary modeling based on High Level Architecture (HLA) is presented. Firstly, the principle and implementation method of mapping one output variable of one model to one input variable of another model are proposed, and then HLA application layer programming framework is given to implement the models, which are developed in different disciplinary simulation software, as federates conveniently and correctly. Five methods of interface to HLA application layer programming framework which must be provided by commercial simulation software are presented also.

Analysis of Software Reliability Modeling on Checkpointing and Rejuvenatio

FAN Xin-yuan, XU Guo-zhi, YING Ren-dong

Software systems often experience an “aging” phenomenon, characterized by progressive performance degradation or a sudden hang/crash. To counteract this phenomenon, a preventive approach named “software rejuvenation” has been proposed. Despite its effectiveness to improve software reliability and availability, rejuvenation is a complex and expensive process. Relative to rejuvenation, checkpointing is a light-level software fault-tolerance policy, the cost of which is much less than that of rejuvenation. This paper presents a new idea to combine both these techniques to further reduce the total downtime cost of software systems. Software reliability models for three cases and their corresponding numerical results are also given.

Search Scope Modeling and Simulation Research for Aviation Searching Submarine Equipments

YANG Ri-jie, HE You, SUN Ming-tai

Considering the equations of active and passive sonar, the target intensity by submarine, the radiated noise feature of submarine, the model of propagation loss in shallow water, the feature of ocean environment, etc., this paper establishes the model of searching scope based on the features and performances of aeronautic equipments for searching submarine. According to the model, simulation results of searching radius under different ocean noises are given. The researches of this paper should provide theoretic foundation for aeronautic searching submarine training.

The Method of System Index Test-Set Production Based on Cloud Model

ZHANG Yong, LI Chang-zheng, WANG Jin, ZHAO Dong-ning, JIANG Yi

The checking and accepting of the electric information system is an important process before it is provided to the users. Based on this thing the cloud model is simply introduced and the necessary of importing cloud model is explained firstly in this paper. And then the test index tree and its’ constructed means are discussed. Then the weight of index and its’ confirmed means are analyzed. Then the method of system index test-set production based on cloud model is proposed. In the end, this paper shows the correctness, rationality and feasibility of the test-set production method with an example.

Implementation of the Message Communication Mechanism Based on Multi-agent

ZHAO Huai-ci , HUANG Sha-bai , ZHANG Xia

With the development of artificial intelligence and computer network technology in extent and profundity, the distributed simulation based on Multi-agent becomes the trend in the future.  It faces the challenge of how to implement the communication and cooperation among agents. In this paper, after discussing the communication mechanism in the distributed simulation system based on Multi-agent, a useful framework based on the message communication   mechanism is provided.

Research of Channel Model in Wideband HF Communication System

XU Fa-qiang

During the research, the channel model is referred to as simplified Watterson wideband HF channel model, which is based on the Mastrangelo wideband HF channel model. And the wideband HF channel is divided into four types which represent four kinds of channel conditions respectively. Furthermore, based on the measurements of the real channel, four sets of parameters for these channel types have been evaluated. In the end, the simulation method for the Watterson wideband HF channel model is proposed.

Simulation Based Exploratory Evaluation Methodology

YANG Feng, LI Qun, WANG Wei-ping, SHA Ji-Chang

The complex system evaluations are facing inherent uncertainty complexities. After analyzing several present approaches for the evaluation of complex systems, especially the commonly used exploratory analysis method, this paper presents a simulation based exploratory evaluation methodology and corresponding process model, which is oriented to the unification of two evaluation levels of system and system-of-systems. Finally, the currents applications and future application domain for this methodology are discussed.

Design and Realization of Vectorization Algorithm on Geological Contour-map

CUAN Ying, YUAN Tong-lu, XU Yong-gao, WANG Xiao-chun

Based on theories of Computer Graphics, Digital Image Processing, Pattern Recognition and combined characteristic of geological contour-map, we present one kind of intelligent tracking algorithm. First, one blueprint is scanned to picture data of BMP pattern with scanner. Then, by applying this algorithm to the picture after pretreatment, we realize its edge-detection and get vector graphical data. As a result, we solve digital problem of geological contour-map.

A Improvement of Beam-Space Reduced Order Root-MUSIC

LIU Yun, LI Zhi-shun

The beam-space reduced order Root-MUSIC is discussed in this paper. Based on sub-array decomposition, the order of the polynomial is reduced to the same as the number of sources. A new method of solving the reduced order polynomial is presented. With the same superior performance of Root-MUSIC, the reduced order algorithm is more computationally efficient. Simulations are conducted to verify the efficiency of the new method and comparision is made with the conventional Root-MUSIC.

Online Algorithm of Representation for Time-series Based on Polygonal Boundary Reduction Method

WENG Ying-jun, ZHU Zhong-ying, Helen Yu

Time series is an important kind of complex data. Analysis and comparison for polygonal boundary reduction and Douglas-Peucker algorithm for time-series representation are implemented at first. Then, a novel online heuristic algorithm of representation based on polygonal boundary reduction is presented in detail. In this algorithm, the sliding window idea has been used for reference. The quality of approximation is as good as polygonal boundary reduction, and it can process the data online in a constant buffer. The number of segments is automatic computed due to the inherent heuristic searching which is based on the allowed maximum error. Higher quality of approximation is accomplished in simulation on stochastic time-series, and also lower computing complexity does.

Parallel Optimization for Markov Control Processes Based on Performance Potentials Simulation

GAO Xu-dong, YIN Bao-qun, TANG Hao, XI Hong-sheng

A Markov control process is an important model for performance optimization in stochastic discrete event dynamic systems, and is widely used in many practical engineering problems. Based on the theory of Markov performance potential, the problems of performance optimization simulation for a class of continuous-time Markov control processes are studied. Since the state space of an actual system is often very large, when applying traditional serial simulation algorithms, long time is possibly spent, or it is impossibly realized because of hardware. A parallel simulation optimization algorithm based on performance potentials is proposed to find the optimal stationary policy of a system. A simulation example shows that the algorithm can achieve high speedup. The algorithm can be used in optimization for large-scale practical systems.

Research on the Mechanism of Real-coded Genetic Operation

CUI Ling-li, XIAO Zhi-quan

First the drawback in mechanism of typical real-coded genetic operation is analyzed systematically, and then the paper puts forward two new modified ways to remedy the drawback. At the same time, these three mechanisms are tested repeatedly by three famous test functions. The simulation results demonstrate the modified ways’ validity.

Support Vector Machines for Regression

DU Shu-xin, WU Tie-jun

Support Vector Machine (SVM) for regression has recently attracted growing research interest due to its obvious advantage such as nonlinear function approximation with arbitrary accuracy, and good generalization ability, unique and globally optimal solutions. An overview of the basic ideas underlying SVM for regression is given in this paper. In particular, new methods such as -SVM, LS-SVM, weighted SVM and linear SVM, and optimization algorithms including decomposition method and SMO and incremental learning with fast computational speed and ease of implementation are concentrated as well. SVM for regression is an important and promising new direction in the area of nonlinear parameter identification, forecast, modeling and control.

A Method of D Optimum Design for Artificial Neural Network

CHEN Jin

The few initial examples are used to calculate preliminary weight matrix, according to the artificial neural network model of this matrix, the design matrix is found out which corresponds to the maximum modulus of the partial derivative vector of the model. According to the example of this design matrix, a new weight matrix is computed and a new design matrix is sought. With output formula of the neural network that is spread out with Taylor progression, the variance of the output function is deduced, it is proved that the maximum modulus of the partial derivative vector is the sufficient condition of the minimum determinant of correlation matrix ( D optimum).

Object Instance Discovery Algorithm Accord with IEEE1516

LU Gang , YAO Yi-ping , WANG Huai-min , LIU Bu-quan

Object instance discovery is a prime concept in object management. Two discovery algorithms are presented in this paper. They comply with IEEE1516 and mainly concern the concepts of subscribe-tree search and candidate discovery class. These algorithms have been implemented in our RTI implementation based on CORBA.

A method for the decision of a point whether in or not in self-intersected polygon

WU Jian , JIANG Hong , WANg Xiao-Chun

In this paper a new method is proposed to decide whether a point is in a polygon, a self-intersected polygon and a ring. A ray is rejected from the test point. According to the position between the edges of polygon and the ray, we define a position function of edges as to the ray, and then count the sum of the position function of all edges. We can decide whether the point is in the polygon, the self-intersected polygon or the ring by the sum. This method applies not only for simple polygon, but also for self-intersected polygon and several simple polygons in the same time. Experiment result indicates that this method is simple, robust and fast.

Simulation Study on the Road Capacity Reliability of Thruway with Exit

GUO Chang-bo , ZHANG Ning

With the development of our economy, transportation comes to be the lifeline of economy. A lot of expressways have been built in many megalopolises. Because on the expressway there is no traffic signal, vehicles could move fast at a high speed. However at the exit, because of the interruption that the right turn vehicle could not move to another lane to the right exit, the passage lane is jammed with a long queue behind the right turn vehicle. The exit becomes the bottleneck of the expressway.  In this paper, with the simulation of the traffic flow at an intersection, the reliability of road capacity is analyzed under the conditions of different arrival rate, right turn rate and priority rate. The flow is supposed as Poisson arrival. Based on the simulation results, some valuable conclusions are given.

Research on Improvement of Automotive Engine Hood with Computer Simulation Techniques

ZHANG Xiao-yun, JIN Xian-long, SUN Yi, QI Wen-guo

Computer simulation for frontal crash of a commercial vehicle with finite element method is described in the paper. Data simulation results forecast that the hinge of engine hood should be ruptured during the crash course and the result have been proved by test. Failed engine hood hinge is danger to driver and passengers, and on the other hand, ability of internal energy absorbed of engine hood should be reduced greatly. According to the simulation result, design of energy hood and hinge are modified on structure and material. The new design has improved the distortion mode of energy hood, and the crashworthiness of auto-body has been improved greatly.

Performance Reliability Assessment for Liquid Rocket Engine Based on Random Weighting Simulation

FENG Jing, DONG Chao, LIU Qi, ZHOU Jing-lun, ZHANG Jing-huai

The performance reliability assessment of liquid rocket engine mainly discusses whether the vital performance parameters and its warp satisfied the demands of the design documents. For the real flying data is very limited, this is a small sample problem. The confidence level of results achieved from traditional statistical method is not high. In this composition, a Bayes approach based on random weighting simulation method is proposed to solve this problem. In the end, an example is given to show how to use this method in engineering.

A New Immune Evolutionary Algorithm and Its Performance Analysis

ZUO Xing-quan , LI Shi-yong , HUANG Jin-jie

An Immune Evolutionary Algorithm is proposed based on evolution principle in the immune system. First, the concept of neighborhood is introduced, and two new algorithm parameters of expansion radius and mutation radius are defined to construct a small neighborhood and a large neighborhood. Second, expansion and mutation operations are given, which use the two neighborhoods to perform local and global search respectively, so that two-level neighborhood search mechanism is realized that searches from global to local regions. The optimization principle and convergence property of the algorithm are analyzed. The simulation results show that the algorithm has nice performances such as avoiding local optima, high precision solution, and quick convergence.

Simulation Research of Multi-Model Coordinated Control System On a 500MW Boiler-Turbine Unit

CHEN Yan-qiao, LIU Ji-zhen, ZENG De-liang, GUO Qing-guang

From the model of a 500MW boiler-turbine coordinated control system, the linearized models of the representative equilibrium working point of the unit model based the sliding press curve have been educed, and the T-S fuzzy model has been constructed by linking together the linear models of the unit with membership functions; Then the multi-variable inner model controller has been designed according to the linearized model; At last, the fuzzy multi-model coordinated control system which uses multi-variable inner model controller as the local controller has been designed. It can overcome the nonlinear characteristics aroused by the change of model working point, and can also guarantee the decouple performance between the control loops. Simulation has testified the validity of the control algorithm.

Three-axis Virtual Flight Motion SimulatorLIU

Liu Zheng-hua, ER Lian-jie, LIU Jin-kun

This paper mainly presents the pedestal architecture of Three-axis Virtual Flight Motion Simulator. During the system, it places emphasis on such modern technique as PDM/CAD/CAE, data engine, virtual assemble & virtual prototyping (VP), and discusses about the work style and mechanism of Virtual Flight Motion Simulator. As for running mechanism, the system, based on PDM, efficiently designs mechanical structure and manages both drawings and producing process. It also realizes dynamic assembling of models using two techniques between OpenGL and virtual assembling tool. The virtual system primarily mimics many characters of the real flight simulator and implements the comprehensive analysis between mechanical system and control system based on VP by adjusting and optimally designing mechanical structures and control methods, developing time of real simulator system is accelerated.

The Fire Calculation Model for Curved Trajectory of Shipborne Gun and Its Simulation Study

PAN Hong-hua, HU Jia-sheng, ZhANG Sheng-yun, WANG De-hu

There exists demerit if shipborne gun only uses low trajectory to fire at different targets. It is necessary to use curved trajectory to satisfy the combat requirement of shipborne gun weapon system. The fire calculation model that includes the model of calculating fire data by solving ballistic equations and the model of fast solving hit problem is set. Using the least-square theory, it is identified the errors of ballistic and meteorological conditions. Simulation result validates the feasible of the model.

Soft-Sensing Model of Oxygen Concentration in Catalytic Reformer Based on PLS Algorithm

SUN Da-zhong, YE Fang-jun, GU Xing-sheng

More and more research has been conducted in the field of soft-sensing modeling. Soft sensors estimate hard-to-measure process variables from other easy-to-measure variables. In this paper, the PLS method has been used to build a soft-sensing model for oxygen concentration in a catalytic reformer. The results show that the models are highly accurate.

The Simulation Study of the Electrical Capacitance Tomography

YAN Hua, GAO Jing

The simulation of electrical capacitance tomography (ECT) system is discussed. The main function and feature of the self-developed three-dimensional finite-element simulation software are described. Its most outstanding feature is the fast calculation of sensitivity distribution. The sensing fields of three different structure capacitance tomography sensors, i.e. type UMIST: with earthed ring guards; type METC: with driven segmented guards and type Bergen: without guards, are analyzed by using the software. Their fringe effects, standing capacitances and the three-dimensional distributions of sensitivity are compared. The analysis results are helpful to the structure selection and the parameter design of capacitance tomography sensors.

Self-turning PID Controller Based on Genetic Neural Networks

HUANG You-rui

A self-turning PID controller based on genetic algorithm and neural networks is presented. It consists of three parts. In the first part, a group of PID parameters are obtained by means of the genetic algorithm. In the second part, neural networks is used to optimize and adjust the PID parameters on-line by exploiting the nonlinear mapping capabilities of neural networks to model objective functions, which ensure that system response has optimal dynamic and steady state performances. The third part is a standard PID controller, which directly controls the object in closed loop. The result of computer simulation shows that the controller has enhanced response speed and robustness .The controller can be used to control different kinds of objects and processes.

Intelligent Compensation System for Grinding Dimensional Error and Its Input-Output Response

TIAN Xin-cheng, XU Qing, PENG Bo, DING Liang

In grinding process, the dimensional precision of work piece shows its uncertainty and non-linearity because of the machine tool property, the grinding wheel, the clamp, etc. Based on the analysis of the causation of grinding dimensional error, this paper puts forward a new intelligent error compensation algorithm, designs an error compensation system and analyzes its input-output response. System analysis shows that the intelligent error compensation system has good stability and dynamic property, and that its stable output is the expected work piece dimension.

Time Series Prediction of Ship Roll Based on Error Back Propagation Wavelet Neural Networ

LI Hui, GUO Chen, LI Xiao-fang

Combining wavelet analysis and neural network characteristics, the error back propagation wavelet neural network based structure and algorithm to ship roll time series prediction are given . The authors complete the simulation experiments using multiple-input/single-output (MISO) wavelet neural network prediction model and the results perform well. This method can also be used in ship pitch and heave time series prediction.

A Kind of Fuzzy Variable Structure Controller Design for Chaotic Syste

REN Ting-zhi

The problem of controlling chaotic Chua circuit has been studied. Using T-S fuzzy model as an approximation for nonlinear chaotic system, the nonlinear chaotic system has been fuzzilized into local linear model. The variable structure controller that is designed by using Lyapunov theory insures the stability of fuzzy dynamic system. The effect of the scheme has been tested by simulation. The fuzzy controller is simple, and needs no much rules.

On the Application of Adaptive Signal Decomposition to Parameters Estimation of Multi-target Echoes

LIU Qing-yun , LI Zhi-shun , LIU Zhao-hui

This paper explores the application of Adaptive Signal Decomposition based on Matching Pursuits algorithm to multiple targets detection and parameter estimation in active sonar signal processing. The method can not only resolve multiple targets, but also extract more acoustic features of the target while providing estimation of its parameters. It not only brings the advantages of wideband signal into full play, but also can solve the problem of multi-path phenomena. So compared with the existing methods, this method has significant superiority. Simulation results have verified it.

An Implementation Method on Intelligent Compensated Predictive Control for Delayed Systems

SHI Xu-hua

An intelligent modeling auto-compensated method based on DMC predictive control’s history data base is produced. The method is suited for delayed perturbation systems. Simulation has verified that the control result of gain unmatching systems has been improved obviously. It was also effective to both gain and delay unmatching system. So, we could reduce measuring requirements for the controlled object and in the meantime strengthen control robustness. We could also wide the application range for the DMC predictive control.

Orthogonal Picture Based Human Face Reconstruction Technology

LIANG Di, SU Zhi-xun

Because of its wide application, computer human simulation is becoming more and more important. Head as the most important character of human has become the most challenging subject of computer graphics. A generic head modification method is introduced in this article, and this method is a combination of scatter interpolation method and DFFD deformation method. By this method the author reconstructs geometry structure of a special human face from two orthogonal pictures. This method has improved outline shape control ability of DFFD method, and at the same time, it can maintain detail adjust ability of DFFD method. Finally this article presents multi-direction texture mapping technique to reconstruct real human face.

Attitude Control of the Feed Source of a Large Spherical Radio Telescope Composed of Two-Stewart-Platform

XIA Yuan-qing, HUANG Yi, XU Ke-kang, HAN Jing-qing

This paper is devoted to the problem of attitude control of the feed source of a large spherical radio telescope. Based on a unique active disturbance rejection (ADRC) method, the lengths of six large-span cables and six electrical linear actuators are regulated to track the ideal trajectory of cabin structure and feed source, respectively. Finally, an illustrative example is given to demonstrate the effectiveness of the proposed method.

Virtual Book Mall on the Internet

ZHANG Ya-rong , ZHANG Hui-lian

In this paper, we propose a design and realize scheme of net-VE based on open technology----java and VRML. In the process of specific accomplishment, client/server communication architecture is employed, and VBM protocol is used to transmit messages between WCVBM server and client applet, and Java applet control VRML plugin’s visualization emulation via external application interface (EAI).