Volume17  Number 10  (2005)

Title Author   Abstract
Research of Evaluation Methodology of Armored Equipment Operational Effectiveness Based on Utility Fusion HUANG Yan-yan, YANG Feng, WANG Wei-ping, ZHU Yi-fan Aiming at the concern on the simulation data which was difficult to transform to the operational effectiveness in the course of evaluating the armored equipment type operational effectiveness, the utility function method was brought forward to solve such a question. An evaluation methodology was developed to evaluate the armored equipment type operational effectiveness. According to the process of the mission, the index system of evaluation was created with stages. By means of collecting the simulation data and dealing with them, the utility functions are adopted to fuse the data into the sub-effectiveness. The sub-effectiveness index weights and sub-effectiveness value were combined into the whole equipment type operational effectiveness. An example for a tank unit military mission of the armored equipment type is carried out, with above methodology used, and the evaluation result demonstrates to be feasible and reasonable.
Modeling and Simulation for Control System of Gas Collectors Pressure in Coke Ovens MENG Yue-bo, JI Qi-chun,WANG Xue-lei Using the pressure of gas collectors control system in coke ovens as an object, a new dynamic model was established applying new thinking successfully. A dynamic process was simulated with the condition of changing position of butterfly valves and disturbance of state in coke ovens by MATLAB software. The rationality and validity of the established model and control method were inspected by simulating results.
Test and Evaluation Realization of Verification, Validationand Accreditation in Modeling and Simulation SUN Yong-cheng, MA Yan-qin, ZHOU Xian-zhong, JIANG Jing-long Creditability of M&S is an important issue of simulation theory research and engineering application. Purpose of VV&A and T&E is to increase credibility of M&S and to reduce risk of simulation system due to incredible simulation result. Firstly, the relation of VV&A and T&E was analyzed, finding that, for insuring the creditability of M&S, VV&A more emphasizes work content while T&E more emphasizes realization method, T&E is the primary technology and method of V&V, and V&V can be realized by T&E. Secondly, the challenges of T&E in M&S were described, and then the T&E realization of V&V was researched during the full life cycle of M&S development. Finally, the method for determining adequacy of T&E was introduced.
Study on Modeling of CGF in EW Based on Agent HAO Cheng-min, LIU Xiang-wei, HU Bo Computer generated force (CGF) is an intelligent autonomous complex system. It is difficult to describe its model accurately with the traditional modeling method. As the extension of Object-oriented method, Agent technology provides effective measures for resolving modeling and simulation problem of such complex system. EW CGF layered modal was built by applying modeling method based on Agent, and the problems of perceiving, action, decision and realization in Agent modal were resolved. The framework, communication language, communication style, cooperation pattern in Multi-Agent System for designing the aggregated entity in EW CGF was discussed.
Random Wave Simulation and Validation Based on Ocean Wave Spectrum YANG Hui-zhen, KANG Feng-ju, CHU Yang-jun, NIE Wei-dong The theory and technicals of verification, validation and accreditation(VV&A) are applied to wave simulation. The linear superposition method and the linear filtering method were compared which wereused to simulate random ocean wave based on JONSWAP spectrum. The spectrum of wave height sequence of a fixed point was verified and validated by compareing with JONSWAP spectrum. The simulation wave data by linear superposition method was used in 3D visual ocean wave simulation and the real-time characteristic was analyzed by testing frame on PC and Workstation.
Modeling of Equipment Battlefield Repair SystemBased on Hierarchy Coloured Petri Net QI Sheng-li, WU Chang, YANG Yi The modeling method is focused which models equipment battlefield repair system based on hierarchy coloured Petri net. The method which applied complex place and sub-Petri net conquered to the shortage of modeling of equipment battlefield repair system based on Petri net. The model becomes directly perceptible and simple, and is fit to be analyzed and simulated.

Modeling and Simulation of Induction Motors Considering Iron Loss

LI Jie, ZHONG Yan-ru A state equation for induction motors considering iron loss in the synchronous frame was developed in order to separate the states and the parameters of induction motors. Then, the simulation model of the motors with iron loss and variable parameters was established based on a MATLAB C MEX-file S-function. The validity, effectiveness and speediness are verified by simulations. The proposed high-efficient model provides a more accurate approximation to actual induction motors for many control problems of induction motor drives.
Finite Element Simulation for Capacitance Extraction of 2D Striplines ZHANG Ying, Janet M. Wang, XIAO Liang, WU Hui-zhong The simulation of the electric field in striplines and the calculation of corresponding electric parameters are very important to the design and fabrication of the striplines. The simulation flow based on the finite element method is constructed, according to which the finite element method is implemented to calculate the electric field of 2D stripline model and the electric field is visualized. The combination of one order Asymptotic Boundary Condition and magnetic wall condition is applied to simplify the calculation. Finally, the numerical result of capacitance parameters is presented.
Stability Analysis for Numerical Simulation Model of Bistable System YANG Ding-xin, HU Niao-qing, WEN Xi-sen

Numerical simulation is the commonly used method in the study of output characteristics of bistable system. The stability analysis of the discrete model is the basis for numerical simulation of bistable system. The current researches haven’t given the stability condition of the simulation model. Through theoretical derivation, the stability conditions of the simulation model with different parameters were proposed. The numerical experiment was carried out and the results coincide with that from the theory. It provides guideline for the choice of system parameters and time step in numerical simulation of bistable system.
Research on Multi-Objective Fuzzy Decision-Making Method Based on GA
YAO Chang-feng ZHANG Ding-hua PENG Wen-li
To decrease the influence degree of objective’s non-standardization in multi-objectives decision- making, an improved algorithm based on GA was proposed. During seeking the answer to multi-objectives decision- making, the objective eigenvalue of each chromosome was computed. Then, the influence degree and the influence degree coefficient caused by the objective’s non-standardization were obtained in each generation. The relative membership degree of each chromosome to the optimized value was calculated based on the influence degree coefficient, and it included the influence caused by the objective’s non-standardization. By changing the objective eigenvalue matrix into the relative membership degree matrix in each generation, the relative fitness function was set up and its value was calculated based on the relative membership degree to reduce the influence degree of objective’s non-standardization to decision-making. At last, an example about resources optimizing deployment was given to prove the algorithm’s feasibility and validity.
Fuzzy Adaptive Interacting Multiple Model Algorithm SHEN Bin, DONG Chao-Yang, CHEN Yu, WANG Qing A fuzzy adaptive interacting multiple model (FAIMM) algorithm is proposed. Based on fuzzy logic, some parameters in the model-set are adjusted on-line so that the model-set adaptive ability to various target maneuvering patterns of this algorithm can be greatly improved. Compared with traditional IMM algorithm, better tracking performance can be achieved by using fewer models. Furthermore, model conflicts problems that arise from traditional IMM algorithm can be avoided and computational burden can be reduced. Simulation results show that the FAIMM algorithm is more effective than traditional IMM algorithm.
Utilitarian Locating Plates Algorithm Designation

LIAO Ming, ZHANG Jin-ling, ZHEN Shu-xin, FANG Hu- Sheng

　

 A utilitarian locating plate method is presented , in which frequency and space topological characteristics about Plate area are considered. Firstly, origin image was processed by gray expanding so that the effects of lighting was averaged and the algorithm was more robust; and the result was handled by morphology gradient operator so that linear shapes of plate area and frequency characteristics of plate were highlighted. Then frequency operator was defined according to havezening frequency characteristics of plate, and some valuable horizontal sets were produced. Thirdly, the horizontal sets were combined geometrically and filtered by geometrical topological. Finally, the slope candidate rectangles patches were corrected and projected vertically. As a result, the correct position of plate comes out efficiently.
The Performance of the High Resolution DOA Estimator for UnderwaterWide Band Sources FENG Xi-an, HUANG Jian-guo Aiming at the application of underwater wide band processing, coherent signal-subspace processing method (CSS) for high resolution DOA estimation of under water wide band sources was studied. By using subspace disturbing analysis to investigate the statistical performance of the CSS, the relationship between the DOA estimation error and the signal to noise ratio (SNR) was presented. The DOA estimation mean square error and resolution probability of the CSS in the Gausian white noise and reverberation were obtained by computer simulations. The research results show that wide band CSS method possesses good performance due to being close to the Cramer-Rao Bound (CRB) of DOA estimation of wide band sources, the low resolution  threshold and the anti reverberation ability.
Density Estimation Based on Support Vector Machines

ZANG Zhao, ZHANG Su, ZHANG Chen-xi, CHEN Ya-zhu

  A new method for density estimation was developed based on the Support Vector Machine（SVM）. This method was used to estimate the density directly from the definition of density.  Several types of SVM based on different regularizer and loss function were used to estimate density in experiments. Compared with Parzen, the results of this method have similar quality and sparse solutions.

Simulation of Underwater Dragging System’s Steady Cable Shape

PI De-fu, SONG Bao-wei, LI Zheng, LIANG Qing-wei

　

The underwater dragging system is widely used in all kinds of field, such as observing geography at the bottom of sea, the basic hydrology data collections, hunting submarines, sweeping the torpedo and torpedo etc. Now the research on the underwater cable is limited in 2D model. And there is so much relevant material about these researches. On the foundation of analyzing and studying the kinetics and dynamics of underwater dragging system, the two dimension mathematic models about planar shape and tension of the underwater dragging system of the AUV were set up. At the end, the model was propgrammed through the calculation about the underwater dragging system with variety navigational speed and different hydrophone, comparing the external form and suffering force. Then a conceive of adding obstruction combining the dragging system’s characteristics was suggested, and the results of the conceive were put out with certain engineering value.
Particle Filter Based on Interacting Multiple Model DENG Xiao-long, XIE Jian-ying, YANG Yu-pu Combining interacting multiple model with particle filter, a new multiple model particle filter is presented. The algorithm used the multiple models to track arbitrary maneuvering of the target. Every model used particle filter to deal with the nonlinear and non-Gaussian problems. After interaction and particle filtering, particles in the models with the fixed number are resampled to reduce the degeneracy of filtering. In the simulations, compared with the general interacting multiple model, the results demonstrate the efficiency of the new filtering method.
Extending SRML Schema Based on DEVS:A Foundation for Simulation Model Representation and Reuse

LIU Chen, HUANG Yan-yan, LI Qun, WANG Wei-ping

The significance of the representation and reusability of SRML being used in simulation models was summaried as well as its drawbacks and the ways to extend SRML schema based on DEVS were discussed. The emphasis was placed on the elaboration of mapping DEVS onto SRML schema to formulate SRML’s basic syntax and semantics for the structure and behavior representation of atomic model and composite model. The model structure, such as property, input interface, output interface and sub-model composition, were described by a group of XML marks. The model behavior, such as external transition, internal transition, output and time-advancing functions, were described by script language and a group of standard interface offered by SRML simulator in Script marks. The SRML element architecture was reviewed and a simulation demo of using SRML to modeling differential equations was given finally.
Study on Semantic Information Model of Crisis Situation ZHONG Wei-jun, WEI Ji-cai2  When applying soft agent as a party of crisis to do crisis decision-making in crisis simulation, it is a key to describe the crisis situation in an information mode that can be understood by computer program. First, by analyzing the essence of crisis situation, the concept of crisis situation was defined. And then, based on the ontology theory, an information mode was put forward that could describe the crisis situation in a way that could express semantic information with structure form. It is the semantic information model of crisis situation. Finally, the way to realize this model was studied based on the technology of XML and Schema.

Development of Automobile Air Conditioning System Simulation Software Based on Modularization Control Technique

WANG Yong, LI Cheng-wu, SONG Si-hong

Design ideas and developing process of automobile air conditioning simulation software are introduced. Components of automobile air conditioning system weredivided into sub-class parts and some reusable part modules weredeveloped by control technique, which could construct automobile air conditioning system. This software has the following functions, namely, system simulation calculation, performance analysis, component matching and optimization, which can help the development of automobile air conditioning system. It has open interface by which user can add his own part modules, easy operation, high speed and accuracy.  
Digital Process Simulation Systems based on LabVIEW ZHU Hai-feng, YANG Zhi, WANG Guo-li The LabVIEW-based Digital Process Simulation systems connect with commercial controllers through 4-20mA or 1-5V industrial standard signals, testing the controllers by simulating various typical processes. The software of the DPS systems have interface to MATLAB and C language, so the DPS systems can work with M-files and C programs as well as commercial controllers. Simulation results show that the DPS systems can simulate processes with high precision, and it will reflect the effect of disturbances and noise in practical industrial processes.

Study on Cognitive Decision Aiding System with Variable Autonomy Level

 ZHOU Rui, YU Zhou-yi, CHEN Zong-ji Intelligent cognitive decision aiding systems have significant effects on improving the effectiveness and safety of the combat plane and decreasing the pilot workload. The distinct behaviors and characteristics in cognitive decision process were investigated. The principles and methods of variable autonomy authority and function allocation were developed from the perspective of cognitive automation and cognitive coordination and cooperation, and the different level of automation was given. The pilot and cognitive decision aiding system were integrated into coordination and cooperation control system with adjustable level of autonomy based on the variable authority management strategies and intelligent information management system, and the integrated system structure was given. The results increase the abilities of coordination and cooperation between pilot and decision aiding system, and improve the performances of modern combat plane.
Multi-objective Evolutionary Algorithm Based on Double Crossover and Its Performances Analysis WANG Zu-zhu, CHENG Jia-xing Evolutionary algorithm is a main and effective method solving a multi-objective optimization problem (MOP). It is a significant approach, in which solutions’ performance of MOP is improved, by using all kinds of evolutionary strategies and techniques. Some concepts about a multi-objective optimization problem were described, and with some operators in several noted algorithms, a multi-objective evolutionary algorithm based on double crossover was designed, and relevant performances were analyzed. The proposed algorithm is not only computationally efficient , but also has good convergence performance，and some method is also applied to maintain solutions’ diversity. The experiment shows it performs well.
Researching Colored Petri Nets Model of Communication Based Train Control System

WU Dong-yong, ZHANG Yong

　

 Communication Based Train Control (CBTC) system is an important development direction of Chinese railway.  On the basis of analyzing the structure of CBTC system, the modeling and simulation of the CBTC were carried out by using Colored Petri Nets analyzing method. Colored Petri Nets is a useful modeling method for describing the structure and function of a system with graphs, which is specially suitable for modeling and simulating a large, asynchronous and concurrent system. In order to make the model simple and clear, a three-level hierarchical CPN model of CBTC is established with the help of CPN/Tools, which includes integral layer, processing layer and functional layer.  This work lays a good foundation for developing the software simulation platform of CBTC system.

Virtual Prototyping Analysis and Simulations of Gun Systems

 WAN Xiao-feng, LIU Geng, YANG Shu-sen The development and application of the virtual prototyping technology are presented. The theoretical basis of multibody system dynamics is also given. By using the commercial software LMS Virtual. Lab, virtual prototyping simulations and its application in the gun system were presented. The simulations of the gun system were validated with the existed experimental results. At last, the dynamic behavior and shooting precision of the system were optimized.
Relative Sensitivity Analysis of Typical Faults of Armament and Thresholds Achievement Based on Virtual Prototyping JIA Chang-zhi, WANG Xing-gui, GONG Lie-hang As conventional land-based military equipment, guns are playing a key role in local wars in recent decades. The typical faults of guns were analyzed, and three indexes to represent guns performance were put forward and three working principles of guns were deduced. Virtual prototype of some-type gun was created by using of ADAMS, and the validation was suggested by comparisons of simulation and test results. The degrees of guns faults affecting performance indexes were obtained based on relative sensitivity analysis, thus the comparison difficulty of fault parameters with different dimensions was solved, and parameter thresholds of guns faults were achieved through virtual prototype according to firing limits of guns. Finally, the perspective of virtual prototyping technology applied in fields of armament engineering was presented.
Method of Synthetic Infrared Scene GenerationBased on Measure Data and Its Implementation ZHANG Jian, ZHANG Jian-qi, SHAO Xiao-peng Abstract：A new method of synthetic infrared scene generation was proposed, avoiding the difficulty part for complex geometry’s infrared radiation calculation in traditional method. By using measure data from infrared imaging device, the new method overcame the disadvantages of poor fidelity in traditional technique. Based on this point, the theory and the key technique were discussed, the programmable pipeline technique was applied to implement this method and the final image was given. At last, both the advantages and disadvantages were compared and what remained to improve next was also presented.
SimulationThree-dimensional Targets of SAR ZHANG Peng, HUANG Jin, GUO Chen- jiang, XU Jia- dong A method of the ground object target simulation of SAR (Synthetic Aperture Radar) raw signal was discussed. The imaging fundamental of SAR was expatiated and the raw echo signal model of complex three-dimensional ground object target was established. The simulation parameters of SAR system were given and the imaging of the complex three- dimensional ground object target was finished.
Research of Key Visualization Technologies in NMD Engagement WANG Wen-guang, LEI Yong-lin, ZHAO Wen, WANG Wei-ping To meet the needs encountered in the visual simulation of NMD engagement process, such as the presentation of both macro and micro scenes, friendly camera control to view lots of active entities, the consistency of multi-local plat coordinates and the global sphere coordinates, a special presentation module, named as Globalview, was elaborated first. Then Globalview-based scene graph and visualization system architecture were designed. Some key visualization technologies of NMD engagement process were detailed at last.

Modeling and Real-time Rendering Technology of Large Scale Grassland

DU Jin-lian, TIAN Chun-shuang, LIAO Hu-sheng The modeling and real-time rendering of large scale grassland is an important part of 3D landscape visualization. An expression method for grassland model was proposed by using grass tufts to create grassland, which could effectively reduce the complexities of grassland model. At the same time, a dynamic simplification method based on the expression was presented. This simplification method can improve the frame rate by. reducing a number of geometric primitives which were not necessary to be rendered during real-time rendering according to the screen projection of the distance between two grass tufts.
Information Visualization and Cooperative Decision Virtual System for Geosteering Drilling XU Ying-zhuo，LI Qi Aiming at the lack of traditional data analysis, deal, interpretation, revelation and decision method, an information visualization and cooperative decision virtual system constructed by the technology of virtual reality and CSCW in the network was put forward. This system can provide a new-style remote immersing information visualization and cooperative decision work environment for geosteering drilling to improve drilling success ratio. The system architecture and the realization of information visualization and collaborative decision environment are in detail described.
Modeling and Rendering of the Infrared Image for Moving Object YU Yan-wen, LIU Yi-jun Realistic infrared image synthesis of moving object is the difficulty technique to produce infrared scene. An infrared image synthesis model for moving object is presented which considers various environmental factors、object surface geometry、structure、intrinsic thermal properties、internal heat conditions and aerodynamic heating due to its high-speed moving. Then the rendering method for infrared image is proposed and the parameter is designed meticulously in order to improve veracity and simplify processes. By incorporating the attenuation effect of atmosphere and the noise mechanism of infrared image sensor, the infrared images of the moving object in the scene from different viewpoint are generated. Experimental results illustrate the potential of our method.
Accelerating Volume Rendering of 3D DatasetsBased on PC Hardware DA Liang-long, YANG Ting-wu, LI Yu-yang, LU Xiao-ting  In visualization of scientific computation, because the volume visualization can display the inner information of 3D data sets, it has become researching emphasis in recently years. Byapplying the technology of 3D texture and Fragment Shader of programmable graphics hardware, the real time volume rendering of 3D data sets with full Phone shading model was realized on commodity PCs. The results show that the arithmetic can create real time high quality image in the medical and military realm.
Simulation System for Robot Virtual Navigation Based on OpenGL FAN Ya-ping, HUANG Sheng-xue, WEN Pei-zhi, WU Xiao jun A robot virtual navigation (RVN) system is presented based on OpenGL. A RVN framework was proposed based on PC platform. The setup of the 3D scene and the control approaches of the orientation and position of the camera and the robot were stressed. In the system, three relative motion states were implemented, that was robot moving while viewer stopping, robot keeping stationary and viewer advancing or both of them moving together. Finally, several snapshots of robot simulation was displayed.
Research on MAS Models for Industrial Supervisory Interface System Based on Rough Set WANG Tao, FEI Min-rui  Rough set was introduced into a kind of interface MAS for industrial supervisory system. An agent digital model, which has knowledge represented and calculation functions, was built. The advantages of rough set were used in classification and the agent was partitioned by its static and dynamic attributes. So the model of the whole MAS was built and it can be represented, deduced and calculated in computers easily. It also lays a foundation for the cooperation of the MAS.
Off-line Programming System of Assembly Robot Based on OpenGL Simulation ZHANG Xing-guo，ZANG Tie-sheng，LIU Ming  One kind of assembly robot built for environment-friendly compressor assembly line is introduced. After analyzing the robot’s kinematics, simulation of the assembly robot based on OpenGL technology was achieved. In this way it is advantageous to plan the path when the assembly robot works. And off-line programming system of the assembly robot for environment-friendly compressor was also developed. The manipulative performance is excellent. With a good man-machine conversation interface, it has been a powerful application of the robot system in the actual assembly task.
Drivers’ Visual Perception Model in Traffic Microscopic Simulation YANG Jian-guo, XIAO Yong-jian, WANG Zhao-an Driver's visual perception model is one part of the vehicle models in traffic microscopic simulation. And the purpose of the visual perception model is to represent the visual perception ability of the real driver, which is to answer what they can see and what they can not. Anew driver's visual perception model was introduced after carefully studying on the movement of driver's visual focus, the visual field, and obstacle shroud. And special attention was paid to the calculation ability of this model. In order to validate the validity of this model, a contrastive experiment was done by comparing the perception objects of real drivers and the model in a simulated scene. 10 testees were invited to this experiment for 194 tests. The testees marked 528 targets, while the model marked 516 targets, among which 84.30% were accordant, 17.61% were missed, and 15.34% were error-detected. After carefully analyzing those test results one by one, the difference between the model's output and the testees' selection was found to be the result of human's perception error, and after they saw the output of visual perception model, no demurral was advanced. Besides avoiding the limitation caused by the perfect global vision, this model reduced the calculation for the simulation.
Adaptive Fuzzy Output Feedback Control for A Class of Nonlinear MIMO Systems

WANG Yong-fu, CHAI Tian-you

An observer-based robust adaptive fuzzy tracking control for a class of nonlinear multiple-input multiple-output systems was presented with plant unknown and external disturbances. It was assumed that only the system outputs could bemeasured, and the state variables were estimated via an observer based on fuzzy basis functions. The adaptive fuzzy controller with an observer could guarantee the uniform ultimate bounds of the tracking errors and the observer errors as well as the bounds of the adaptive parameters. First, a nonlinear observer was designed based on FBF to estimate the state variables in which a fuzzy logic systems was introduced to learn these unknown (or uncertain) dynamics by an adaptive algorithm. Then, an indirect adaptive fuzzy controller based on fuzzy observer was presented. Simulation results demonstrate the applicability of the proposed method achieves the desired performance.

Research on Adaptive Filtering Based on Fuzzy Neural Networks

MA Ye, WANG Xiao-tong, DAI Yao

 An algorithm of adaptive fuzzy Kalman filtering is presented. According to relativity of innovation, the measurement noise covariance(R) was adjusted adaptively based on the fuzzy rule. The method couldcope with divergence problem caused by the insufficiently knowing of the prior filter statistics. Simultaneity, the Elman network was employed as a compensating error estimator to compensate estimation error of the fuzzy Kalman filter. Simulation result shows that the presented method reduces the error of actual filter, improves the accuracy and can amend filter's parameters on-line.
Optimal Motion Control and Simulation of Redundantly Actuated 2-dof Planar Parallel Manipulator ZHANG Yao-xin, CONG Shuang  Based on the redundantly actuated 2-dof planar parallel manipulator, the optimal motion control of such a system performance was studied. Dynamic model of the parallel manipulator was established and optimal controller based on quadratic performance index of system error and control was designed. The problem of optimal parameter design in Point-to-Point motion control was analyzed. In order to solve the problem of the low speed in Point-to-Point motion control, interpolation method was adopted. By computer simulation, the relation of high-speed and high-precision continuous path control with number of the interpolation point was studied and the effects on improving the precision and the speed of response of the parameters were compared and analyzed.
Genetic Algorithms Attack on NTRU public-key cryptosystem ZHAO Xiao-long, WANG Yan-bo, LI Bin, YU Jie-shan  A method to attack NTRU public-key cryptosystem utilizing a genetic algorithm to search the key space is presented. According to the NTRU private key’s characteristics, order coding was selected as the GA’s representation, crossover operation was implemented based on a group of circular genes in parents and the fitness was measured by the ratio of the number of the private key’s coefficients between [-1,1] to the total number of its coefficients. Simulation experiments show that the solution which reduces the search space 2 orders in quantity is reasonable.
A Novel OFDM Parameter Selection Scheme over Time Varying Multipath Channel HAN Xiang, WEI Ji-bo The ISI and ICI in OFDM system in both cases of CP length longer and shorter than the max delay were analyzed. According to the analyis, a method was proposed that first determine CP length based on delay distribution and then the number of sub-carrier. Through simulation, it is proved that the proposed method is better than the conventional parameter design method in performance. So the conclusion is instructive to parameter selection in designing OFDM systems.
Research on Method of Demodulation for PCM/FM SignalBased on Instantaneous Frequency Measurement LIU Dong-hua, WANG Yuan-qin, YUAN Si-jie, FENG Chun-yan, DU Guo-xiang Based on the theory of instantaneous frequency measurement, a method of software demodulation for PCM/FM signal with Doppler frequency offset is presented. Firstly, through estimating Doppler frequency by instantaneous frequency measurement, the method not only corrected the frequency offset of PCM/FM signal, but also improved the precision of bit synchronization. Then, according to the relation between two closed points of bit synchronization, the demodulation was realized. The basic theory and the course about the method were discussed. Some factors were analyzed that could affect the precision of instantaneous frequency measurement and the effect of Doppler frequency offset on demodulation. Themethods were proposed to improve the precision of instantaneous frequency measurement and the performance of demodulation. The results of computer simulation show that the method with a bright future for application is good at anti-jamming, better than other methods of demodulation and convenient to be realized by software and DSP.

Simulation Implementation of LDPC Codes Based on Signal Processing Worksystem

　

 XU Wei-kai, WANG Lin In the communication systems designing, it has been an absolutely necessary stage to use advanced simulation tools for modeling and simulating. SPW is an advanced tool for modeling and simulating communication systems, and it has very flexible capacity for user-defined token. LDPC code is an effective error-correct code for these years. Its performance is better than that of turbo codes. User-defined token of LDPC code was designed on the base of introducing the principle of LDPC code, and the performances of LDPC code on AWGN and Rayleigh fading channel in SPW environment were simulated, respectively. The simulation results are expectant.
Image-adaptive Watermarking Algorithm Robustto Geometric Distortion in DWT Domain HU Yu-ping, HAN De-zhi, YANG Si-qing The wavelet transform has no ability to resist to geometric distortion, so the wavelet domain watermarking resisting to geometric distortion is a very difficult and challenging subject. A watermarking algorithm robust to geometric distortion in DWT domain is proposed. In the algorithm, a watermark was embedded adaptively in low band of DWT domain, according to the conceal quality of Human Visual System (HVS)；Especially, the geometric transformation could be corrected before the watermarking detection， owing to embedding a template in a circle of middle frequency in DFT and extracting a invariant centroid from a restricted area inside the image. The experimental results show that the watermark is robust to geometric distortions and general image processing techniques.

Neural Adaptive Sliding Mode Position Tracking Control of DC Motor

XIE Zong-wu, LIU Zi-long, LIU Hong

A neural network sliding mode-based adaptive control strategy is presented for position tracking of a DC motor with unknown system nonlinearities. In the proposed scheme, some existing techniques were integrated, such as the input- outputlinearization technique used to cancel the nonlinearities, and neural networks used to implement the linearizing control law. It is shown that through the proposed control scheme, the rotor position of a DC motor can follow any arbitrarily selected trajectories under variable load torque. Applicability of the approach is tested via simulations.
Robust Guaranteed Cost Filtering for Linear Uncertain Neutral Systems with Markovian Jumping Parameters FU Yan-ming, SU Hao, DUAN Guang-ren Robust guaranteed cost filtering for a class of linear neutral systems with Markovian jumping parameters is investigated. The system under study involves time delays, jumping parameters and uncertainties. The transition of the jumping parameters in systems is governed by a finite-state Markov process. The objective is to design linear memoryless filters such that for all uncertainties, the resulting augmented system is robust stochastically stable independent of delays and satisfies the proposed guaranteed cost performance. Based on stability theory in stochastic differential equations, a sufficient condition on the existence of robust guaranteed cost filters is derived. Robust guaranteed cost filters are designed in terms of linear matrix inequalities. A convex optimization problem with LMI constraints is formulated to design the suboptimal guaranteed cost filters.
Variable Structure Control for Nonlinear Discrete-time System WANG Zhen-yan, ZHANG Jing-gang, CHEN Zhi-mei A variable structure control method based on neural network reaching law for a class of nonlinear discrete-time systems was proposed. Parameters, ε and δ, which were determined previously in the conventional reaching law, were regulated adaptively by two neural networks respectively, and network weights were updated by the deviations between discrete reaching control law and discrete equivalent control law. It is shown that all advantages of the reaching law are retained, meanwhile the dynamic features of the control system are improved effectively and system chattering is eliminated. System can move perfectly on the sliding-mode surface. Theoretic analysis and simulation results prove the validity of the method.
New Method for Controlling Freeway On-rampBased on Fuzzy Logic ZHANG Yan, CHEN Yang-zhou As the uncertain features of the freeway traffic flow, fuzzy control can be used as an acceptable way to solve traffic problem. A new Fuzzy Ramp Metering controller is proposed that includes fuzzy decision maker to output the cycle time for traffic light and a switching function to decide the change making of the light. Six elements for freeway condition serve as inputs for the control process. Simulation results has been compared to the ALINEA method according to performance index.

New Model Building Method for Cycloconverter Simulation

YE Zhi-hao, ZHANG Xiao-feng, WANG Xing-wei, YANG Feng  Based on the triggering principle of cosine-crossing method, the logic relationship of thyristers triggering of 6-pulse single-phase cyclo onverter was established. On the base of this relationship, the simulation program using Simulink S-function was compiled. The simulating analysis on output harmonic voltage of 6-pulse single-phase cycloconverter was carried out. The consistency between simulation results and theoretical results prove the simulation model established is correct. The correctness of cycloconverter simulation model is important to further research on cycloconverter-fed synchronous motor speed regulating system.
Model and Simulation of Discarding and Collision of APFSDS YANG Fu-feng, RUI Xiao-ting, ZHOU Xiao-li  APFSDS is the main weapon that kills the armor target in battlefield. The dispersion of APFSDS was affected by the collision phenomenon that was found between sabot and long rod and between sabot and sabot in the post-effect period. The unified dynamics model was established and collision problem between the sabot and the long rod and the sabots was analyzed. The movement of sabot and long rod outside the bore was simulated, and the essential method that optimizes the sabot and long rod configuration and improves the dispersion was provided.
A Simulation Model for Calculating the Response Time of a Supply Chain Network

Ding Yi-zhong

 The response time of a supply chain network is an important criterion for supply chain assessment. However, the existing approaches to calculating the response time can hardly describe the  behavior of the whole network. A practical simulation model of the response time of a supply chain network is established. in this paper. This model is used to calculate the response time, which can describe the integral response behavior as well as the stochastic property of a supply chain network.

Resource Leveling Optimization of Network Scheduling under Probabilistic Time and Cost

XU Zhe, LI Ke, LIU Rong The optimization of Network Scheduling concerning the fixed completion time - resource leveling was studied. The time and cost of Network Scheduling activities are probabilistic, and the time-cost model isn’t uniform distribution. A Monte-Carlo simulation model of Network Scheduling was established, and simulation output data of time and cost were analyzed. The methods for statistical analysis of getting a representative sample were studied. A Determinate Network Scheduling was constructed according to the representative sample of the simulation output data. The time-cost model of the determinate Network Scheduling activities was assumed as Weibull distribution, and a multi-apex Weibull time-cost model was presented counting the cost of every activity in the same time during the life time. Finally, the heuristic method of leveling resource need peak was studied, and a more leveling time-cost distribution model was gained.
Simulation of Vibration Characteristics of Active Controled Hydraulic Mountwith Electrostrictive Actuator SHI Wen-ku, ZHENG Rui-qing, MIN Hai-tao An active engine mount with electrostrictive actuator was studied. Its simulation model was built using Matlab, and the nonlinear characteristics of inertia track, decoupler, and electrostrictive actuator was considered in this model. An adaptive controller using the filtered-X LMS algorithm was selected to cancel the force transmitted from the engine to body through the active mount in this simulation. The simulation results show that vibration transmitted from the engine to the body can be reduced greatly. The control voltage applied in actuator was calculated by table looking, and by this method and the influence of electrostrictive nonlinear on system isolation characteristics was canceled.

Analysis of Optimal Chaotic Binary Sequences in Asynchronous DS-CDMA

 LI Xiao-chao, GUO Dong-hui, WU Bo-xi  In order to generate the optimal spreading sequences for asynchronous DS-CDMA, some optimizing criteria for selecting chaotic binary sequence were proposed. In order to prove our analysis, these criteria on Chebyshev chaotic sequences were implemented to get the optimal chaotic binary sequences set. The agreement between theoretical analysis and simulation result shows this sequence set reaches the optimal performance and is suitable for asynchronous DS-CDMA.

Method of Timed Petri Nets Simulation

in  Dam Concrete Construction Processes

YANG Xue-hong, LIU Quan, FAN Wu-yi, JIAN Xing-chang The method of timed Petri nets simulation models construction system was modeled by using the theories of Petri net and the relationship was described between the parameters of construction and the construction proceeding. The timed Petri nets model of construction system could demonstrate the dynamic change of the real construction system well. The construction process of dam concrete construction and its procedure systemically were analyzed and the mathematics models of the simulation process were proposed based on timed Petri nets and multi-objective decision. A case shows that the simulation method and the models are feasible by simulating the dam concrete construction process.

Simulation Framework for Spacecraft Attitude Dynamics and Control Based on Matlab/Simulink

ZHOU Li-ni，TANG Guo-jin，LUO Ya-zhong

　

 The simulation framework for spacecraft attitude dynamics and control using the Matlab/Simulink software was established. The optimization design of PD controller parameters and attitude simulation for a spacecraft with wheel actuator were completed based on this simulation framework and the Nonlinear Controller Design blocksets. The results show that: 1) The simulation framework based on the Matlab/Simulink software for spacecraft attitude dynamics and control has several advantages such as better reusability and inheritability; 2) The optimization design of controller parameters for nonlinear system can be effectively completed by the Nonlinear Controller Design blocksets.
Dynamic Characteristic Study on New Tractor-Brake Hydraulic Torque Converter LI Ji-yuan, YAN Qing-dong Based on one-dimensional flow theory, the dynamics characteristic of new tractor-brake torque converter is analyzed. The models of tractor and brake dynamic characteristic are built based on conservation equation. Simulation and result analysis prove the validity of the models.
Emulation Analysis for Suspension Line Fracturing ZHANG Hong-ying，TONG Ming-bo，WANG Yue-quan Combining an airdrop accident, the stress passing pipelines in the canopy fabric was analyzed. According to the stress passing pipelines, the software ADAMS was adopted to build up the kinetics model of the main parachute system in the parachute’s inflation, and simulate the situation that all suspension lines were in good condition and the situation that some suspension lines were fractured. The results show that the parachute, on which the numbers of suspension lines are 96, when the numbers of lines continuously broken reach 16, the residual lines will not be broken. Thus, the reason for the failure that deploying main parachute is that the tightened lines are impacted by other objects (just as parachute module scoop, other flyers in the air) in the process of deploying main parachute. Finally, the proportional gene  from the test validated extremely approximates to the simulation (the discrepancy is only 0.001). This proves that simulation’s tendency conforms to test’s.

Simulation Study of Load Dispatching for Power Generating Units Based on Optimized Commitment Method

WANG Shuang-xin, MA Ling, LI Ya-guang A new optimized unit commitment method which combined the priority list and dynamic programming is presented to solve unit load dispatching problem. Not only does the new method calculate the start-up consumption that the priority list can’t consider, but also it resolves the dimension problem of dynamic programming and the unit ramp constraint. The experimental and simulation results applied in the load economic dispatching system indicate that the proposed algorithm has more practicability.
Application of Recurrent Neural Network to Earthquake Response Analysis of Rock-fill Dam HAN Min, SHI Zhi-wei

 A kind of recurrent neural network was applied to the earthquake response analysis for Rock-fill Dam. The neural network model contains the feedback of the state neurons and takes the form of state space representation. With the approximation capability and dynamic information storage capability, the neural network model was trained to reconstruct the input-output characters from the observed input-output data. The model trained could perform response analysis and make prediction for new earthquake wave. Two data sets were used to test the method, the one was from a finite element program, and the other was from a real-life experiment. The responses of Rock-fill dam are well modeled, and the simulation result for new data indicates the better prediction ability.

Research on Subjective and Objective Evidence Fusion Method in Oil Reserve Forecast ZHANG Xiao-dan, ZHAO Hai, WEI Shou-zhi  A new fusion model was proposed, that the model integrated BP neural networks combination with DS evidence reasoning to solve the problems about traditional signal model’ complicated degree of arithmetic which was high and exact in probability and low in oil reserve forecast. The method not only realizes feature level fusion of all subjective and objective evidence on different levels in all fields, but also realizes the predominance compensation of different models. Through experiment analyzed, the method can improve classified precision 6.9％ and reduce time complication degree.
Fuzzy Neural Network Control of Activated Sludge System HU Yu-ling, CAO Jian-guo, QIAO Jun-fei  According to practical situation of wastewater process, one control model was built based on mechanism model of activated sludge wastewater process. Based on analysis and synthesis of system, an effective fuzzy neural network controller was proposed. Through simulation test, the result shows that this fuzzy neural network controller has more robust than traditional fuzzy control based rules and can observe good dynamic characteristics.
Simulation Research on Suspension Characteristics of Tracked Vehicles Based on Multi-Body Dynamics Theory CHEN Bing, HUANG Hua, GU Liang2 A multi-body dynamics method of real body modeling was used. Taking a type of tracked vehicle as an example, full vehicle models of real-body and suspension system were built and nonlinear characteristics of suspension system were analyzed. Dynamics characteristic of the full tank vehicle model was analyzed in simulation by changing suspension parameters. Comparison results of simulation and field-testing show that multi-body modeling method is valid in researching vehicle suspension dynamics. The ride-comfort of vehicle was also studied by multi-body modeling method. A conclusion is drawn from the results that ride-comfort of tracked vehicle can be improve when suspension parameters are changed with different conditions, that is to say if semi-active suspension systems of changing damping ratio is applied to tracked vehicles, their ride comfort will be improved obviously. The model can describe dynamic performance of a real driving vehicle, and this method can be applied to investigate dynamic characteristics of other similar vehicles.
Priority-driven Scheduling Algorithm Based on Weight FU Jie, LI Ren-fa The classical earliest deadline first algorithm for resource scheduling was introduced and the priority reversal problem was analyzed. And then, a scheduling algorithm based on weight was presented. In this algorithm, RTOS assigns weights to resources and sets up evaluation function. This algorithm is implemented with resource weight table and evaluation function. Experiments on the modified embedded RTOS show that the algorithm better allocates resources and overcomes priority reversal problem, in addition it also improves stabilization and real-time performance of Embedded RTOS effectively.
Research of Key Technology for Distributed Simulation Grid