Table of Content

30 October 2004, Volume 25 Issue 5

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Paper

Simulation and Analysis of Influential Factors of Ride for High-Speed Tracked Vehicles

1:Han Baokun,Wang Changtian;2: Li Xiaolei,Huang HUA

2004, 25(5):  513-516.  doi:10.3969/j.issn.1000-1093.2004.05.001

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Simulation plays an important role on the systematic research of tracked vehicle dynamics. A multibody dynamic ride model of the tracked vehicle was established and was proved to be valid. On the ba?sis of this model, the factors influcencing ride quality were analyzed.丄'hese factors include road roughness, speed and structual parameters. Influence of terrain roughness on the ride was given by traveling on good terrain, medium and rougt terrains. Influence of velocity on the ride was shown by traveling in different speeed. Analysis of influence of damping on ride quality provides some guidance to semi-active control of tracked vehicles. The results are beneficial to strengthening the roles of simulation in the research and to improving the performance of tracked venicles.

Fuzzy Method in Judging the Capability Grade of Gun Barrels

Liu Huanzhang, Zhang Weifeng, Yuan Xingping

2004, 25(5):  517-519.  doi:10.3969/j.issn.1000-1093.2004.05.002

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It is a gradual retrogressive process in the use of a gun barrel from being brand new to being finally discarded as useless. The capability grading of a barrel was never judeged and graded. But with the improvements in the firepower of gunnery, it becomes important to study and grade the capability of the barrels. In this paper, a fuzzy, synthetic judgement theory is proposed to set up an one-level fuzzy synthetic judgement model. By analyzing the criteria in judging the characteristic grades of barrels, the model can be applied to categorize the grading of barrels.

Modelling and Simulation of Dynamics for the Self Propelled Artillery Running on the Road

Qian Mingwei, Wang Liangming

2004, 25(5):  520-524.  doi:10.3969/j.issn.1000-1093.2004.05.003

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A method of synthesis of the multibody system dymanics is applied in the kinematic and dy?namic analysis of self propelled artillery running on the road. For the self propelled air defense artillery, the system is divided as 5 rigid bodies, viz. the vehicle, the turret, the gun, the tracking rotation platform and the tracking pitch platform. Ihe total system is supported on the ground by the suspension system and the road wheels. The artillery system has 7 D. O. F，and the dynamic model of the system was developed, and the final formulation of the dynamic equations was completed by computer programming. Dynamic proper?ties of the system when running on the washboard- type or the twist-type roads were simulated and the mo- tion of pitch and roll of tlie vehicle was obtained. T-Iie results are important in the system design and dy?namic evaluation of the self propelled artillery.

Gray Relation Analysis on the Performance of Shaped Charges

Zhang Xianfeng, Chen Huiwu, Zhao Youshou,Huang Zhengxiang

2004, 25(5):  525-528.  doi:10.3969/j.issn.1000-1093.2004.05.004

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Gray theory are applied in such fields as sociology, economics, geognosy, bionomics etc. The paper applies gray theory and technique in the design of shaped charge, using grey relational space to analyse the structural parameters and effect parameters of explosively formed projectiles, getting the grey relational matrices which influ?ence the parameters of EFP and using the grey relational matrix to help the choice of structural parameters for shaped charges. Numerical simulation results show that it is effective to applv the grey relational matrix in the design of EFP. The results indicate its value in generalizations in similar fields of application.

Engineering Design of the Focus Curve of a Fragmentation Damaging Warhead

Li Jinqing. Hu Huanxing

2004, 25(5):  529-531.  doi:10.3969/j.issn.1000-1093.2004.05.005

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Engineering design of the focus curve of fragmentation damaging warhead was discussed. A numerical method used for the engineering design was given. A typical example was calculated for the focus curve. It is indicated from the calculation and experiment that the method can be of use in warhead design.

Determination of Nitrate Content in Polyethylene Polyammonium Polynitrates

1:Dai Rongji, Gu Junling,Fu Bufang;2:Yang Rongjie ,Tong Bin,Zhang Ziqing

2004, 25(5):  532-534.  doi:10.3969/j.issn.1000-1093.2004.05.006

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The nitrate contents in five kinds of polyethylene polyammoniums polynitrates were deter?mined using nitrate selective electrodes. The five kinds of polyethylene polyammoniums polynitrates tested were respectively ： ethylene diammonium dinitrates (DAN)，diethylene triammonium trinitrates (TrAN)， triethylene tetrammonium tetranitrates (TeAN) , tetraethylene pentanimonium pentanitrates ^PeAN) and polyethylene polyammonium polynitrates (PoAN). Effects of Various experimental conditions such as pH value, presence of other ionics on the results were studied, and the optimum experimental conditions were settled upon. The results showed that determination of the content of nitrates in polyethylene polyammoni?um polynitrates using nitrate selective electrodes is simple and reliable.

Distortion Analysis and Optimization of Fractal Source-Channel Image Coding

Mu Xiaomin, Zhang Dehui, Yang Shouyi

2004, 25(5):  535-539.  doi:10.3969/j.issn.1000-1093.2004.05.007

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There are several different parts of data in quad-tree fractal image compression. Each part is different in the sensitivity to the communication channel noise. In this paper, the different sensitivities of each part of fractal image compression data to the communication channel noise were first analyzed. Based on this, a combined source-channel coding of fractal image compression was proposed. Distortion of the pro?posed coding scheme was analyzed and an optimal algorithm was used to minimize the total distortion.

Estimation of Range Error in Bistatic Airborne Sonar Searching for Submarines

Yang Rijie ,He You, Tian Baoguo

2004, 25(5):  540-543.  doi:10.3969/j.issn.1000-1093.2004.05.008

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Based on the range model of bistatic airborne sonar searching for submarines, the range error model and error coefficient model for Distatic airborne sonar searching for submarines were established to confirm the factors (such as underwater sound speed, direct-wave time, reflect-wave time, azimuth angle etc. ) which have influence on distance precision. According to the mathematical models, simulations were made to analyse the eccentricity and azimuth angles，influence on each error coefficient and the searched submarinesJ distance relative mean square error. The simulation results show that this method can get satis?factory effect. This paper provides a gist for further research on bistatic airborne sonar searching of sub?marines.

Measurement of Extremely Low Frequency Field Caused by Shaft-Rate Modulated Corrosion Current

1：Lu Xincheng, Gong Shenguang, Liu Shengdao；2：Sun Ming

2004, 25(5):  544-546.  doi:10.3969/j.issn.1000-1093.2004.05.009

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Due to electrochemical effects corrosion current circulates between steel (of the hull) and bronze (of the propeller) in sea water. The current returns from the propeller, through the shaft, and through various bear?ings, seals, and mechanical routes back to the hull. The electrical impedance of this return path varies as the shaft rotates, causing modulation of the electrical current in the sea-water. These timfrvarying currents generate electric and magnetic waves that propagate from the ship. By using the ship model and Ag/AgCi electric pole, the extreme?ly low frequency electric field produced by corrosion current modulated by shaft rotation in sea water was measured in the laboratory. Experiments show that, modulated by shaft rotation, the corrosion current between the hull and propeller, which are made of different metals will generate an ELEF at the shaft rotation rate. Therefore, the ELEF becomes an important characteristic of a ship.

A Study on the Thruster Properties of Micro Chemical Thrusters Charged with Different Propellants

Ma Lizhi, Shen Ruiqi, Ye Yinghua

2004, 25(5):  547-550.  doi:10.3969/j.issn.1000-1093.2004.05.010

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Micro chemical thrusters having the structure of three layers were designed for experiments. When the propellants used were lead styphnate and nickel hydrazine nitrate respectively, with nitrocellulose as the binder, their thrust properties were studied under different chamber diameters (0. 5 ?I. 5mm) charged with different proportion of propellants. Experiments testified that the thrust of lead styphnate was about 0. 05?0. 38mN, its impulse was about 3. 2 X 10-5?3.0 X 10-4 mN.s in 0. 3?2. 8mg charges, and the thrust of nickel hydrazine nitrate was about 0.06?0.25mN，its impulse was about 1.8X10—3?1.0X 10-2 mN? s in 1.0?3. 2mg charges.

Investigation of the Guidance Law for an Image Homing Guidance System

Shangguan, Yinli

2004, 25(5):  551-555.  doi:10.3969/j.issn.1000-1093.2004.05.011

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The paper aims at a kind of image homing guided missile. By calculating the miss distance of an image guided missile, the paper analyzes the guided trajectory characteristics and the start control condi?tion of the homing guidance. Several modified proportional navigation laws easy for engineering implementa?tion are introduced.

A Study on the Launch Dynamics of Multiple Launch Rocket System

1：Rui Xiaoting,Lu Yuqi，Wang Guoping，He Bin，Lu Wenguang ；2：Yun Laifeng；3：Zhao Kesheng;4:Cheng Weidong

2004, 25(5):  556-561.  doi:10.3969/j.issn.1000-1093.2004.05.012

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Launch dynamics of Multiple Launch Rocket System(MLRS) was studied in theory from the point of view of the whole system including the rockets, launcher, propellant and environment. The launch dynamics model and launch dynamics equation of the multibody coupled rigid bodies and elastic bodies in the MLRS were established. Orthogonality conditions of augmented eigenvector were presented. Response of the MLRS was simulated, and the simulation of response oi the MLRS was verified. The basis to analysis of dispersion and reduction of rocket in the test oi MLRS was established in this work.

A Virtual Environment Missile Equipment Maintenance Services System

1:Liu Yuhai;2:Zhang Xi' En

2004, 25(5):  562-566.  doi:10.3969/j.issn.1000-1093.2004.05.013

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Virtual reality technology, when applied in equipment maintenance training can enhance the competency of operators on the virtual equipment just as on the real equipment, and enjoy convenience with less expense. In this paper, a virtual missile training system was described. The system concept, construc?tion of the system, and the method of implementation were introduced.

Method of Initial Alignments of a Short Range Missile with Strapdown Inertial Guidance System

Qi Zhanyuan, Zhang Jing, Zhu BoLi

2004, 25(5):  567-571.  doi:10.3969/j.issn.1000-1093.2004.05.014

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In order to solve the problem of initial alignment for a short range strapdown inertial guided missile when the launcher was supported on the shoulder of an antitank personnel，and to analyze the infIu- enc of the inertial sensor errors to alignment, the method oi initial alignment was suggested. The alignment method measures and takes the average of initial disturbance accelerations before firing the missile. Estab?lishment of the method was based on alignment experiments. Mathematical model oi initial alignments was set up by Drojecting the specific force vector to a stable temporary platform coordinate system in an inertial space. An error analysis model was obtained through coordinate and similarity transformations. The initial alignment model was verified and validated through digital simulation experoments. Error distribution oi in?ertial sensors is proviaea based on the error analysis model.

Kinematic Analysis of a Hydraulic Mine-Clearing Mechanical Manipulator

Xie Qinghua, Zhang Qi, Yang Xiaochuan

2004, 25(5):  572-575.  doi:10.3969/j.issn.1000-1093.2004.05.015

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In analyzing the kinematics of the hydraulic maipulator operating system, the generalized co?ordinates of the manipulator system was established. The rotating and moving joints were selected from the mechanism as joint variables. The generalized transformation matrices were worked out. The kinematic e- quation at the finger end of the manipulator was calculated, and the obverse solution for manipulator was obtained. The operating geometrical parameters and primary techno-index of the manipulator system are simulated. The simulation results showed that the manipulator operating system meets the working task re?quirements. The study provides a theoretical basis for optimizing the structural parameters. It verifies the feasibility that the manipulator can be used in an engineering equipment platform.

A Fuzzy Pattern Recognition Model for the Threat Evaluation of Targets

1:Pan Honghua, Wang Jianming, Zhu Sen, Wang Dehu;2:Hu Jiasheng

2004, 25(5):  576-580.  doi:10.3969/j.issn.1000-1093.2004.05.016

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Threat evaluation of targets, an important part in warship s C3I, was the judgement of threat level. A fuzzy pattern recognition model for threat evaluation of the air targets was presented. With the pri?or knowledge as a guide，a semi 一 supervised iteration identiiymg algorithm for identiiymg the parameters of fuzzy pattern recognition is established. The threat of targets can be recognized in time. A case study showed the effectiveness of the model.

A Basic Study of Hydraulic Telecontrol Systems Based on Internet

Wang Xiaofeng, Wu Pingdong, Huang Jie,Cheng Zhilong, Ma Shuynan ,Ren Changqing

2004, 25(5):  581-585.  doi:10.3969/j.issn.1000-1093.2004.05.017

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Taking a hydraulic system as the object of control, a study on the telecontrol system is worked out based on Internet. Results of simulation and experiments show that adoption of proper compensator structure and intelligent forecasting algorithms can solve the problem of performance on hydraulic telecon?trol systems caused by Internet-inducing time delays, and reduce its uncertainty during the transportation of control information through the Internet. Ihis makes the feasibility of mechanical telecontrol through In?ternet. The paper introduces other problems requiring study during the realization of the telecontrol system： necessity and methoa m treating sampling information in the remote end, necessity and the method in the reappearance of Internet-induced time delays, and their uncertainty in the experimental platform.

Metric in Bayesian Networks Based on the Evolutionary Algorithm

Yang Youlong, Wu Yan

2004, 25(5):  586-590.  doi:10.3969/j.issn.1000-1093.2004.05.018

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Characterization of the population in evolutionary algorithms using graphical models is of ad?vantage to express the whole construction and inherent relations of genetic information. The technique of speedy and effective to creation of a graph and its metric is the key of success to integrate these graphical models into an evolutionary algorithm. Bayesian networks are directed acyclic graphs, and they are one of the important graphical models. To analyze the structure of Bayesian networks based on evolutionary algo?rithm, some definitions with the property of the Bayesian networks metric were introduced in this paper. For any two gene locations a and b of chromosomes (that is, any two isolated vertices of Bayesian net?works) ，he paper analyzed the metric relationship among three graphs containing an edge from a Xo b , from b to a and with no edge. At the same time the efncient approach to study the structure of population on evolutionary algorithm was also put forward.

A Clustering Algorithm Based on Highest Vector-Weighted Independent Set in Wireless Network

1:Zhao Chunxiao;2:Wang Guangxing

2004, 25(5):  591-594.  doi:10.3969/j.issn.1000-1093.2004.05.019

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A mobile ad-hoc network is a multihop wireless network, where the nodes communicate with each other without any pre-deployed infrastructure. The most important problem on such dynamic networks is to find routing algorithms performing well in most cases. Cluster based algorithms are among the most ef?fective and scalable methods. However,due to the highly dynamic topology and the absence of any fixed in?frastructure in a mobile ad-hoc network, a reconfiguration of the system is often unavoidable. So, it is vital to keep the topology stable as long as possible. MWIS(maximal weighted independent set)is a clustering al?gorithm. It is used to partition the whole network into non-overlapping clusters, where a clusterhead is elected in each cluster. Based on MWIS, HVWIS (highest vector-weighted independent set) algorithm was proposed. First, a vector weight is assigned to each node, its motivation is to tnink over the neighboring multi aspects. Second, the algorithm uses a fuzzy decision model. Thus, the clusternead that forms a HVWIS in the network determines the topology and its stability. The correctness of HVWIS algorithm is proved and its time complexity analyzed.

Resource Management and Task Management Based on Space Networks

1:Jiang Yueqiu, Pan Chengsheng;2:Li Hang, Wang Guangxing

2004, 25(5):  595-599.  doi:10.3969/j.issn.1000-1093.2004.05.020

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Resource management and task management were first defined. On the basis of multiplex net-work management protocol (MNMP)，the architecture and method of implementation were designed and solved in describing and selecting the networks resources. Management of resources and task management can utilize the network resources maximally ana improve using efficiency of space networks. It makes net?work management heighten the support to application.

Short Papers

A Study on Underwater Passive Sound Reflectors

1:Zhang Xiaofeng,Zhao Junwei Bai Yinsheng;2:Zhou Shihong,Wang Rongqing

2004, 25(5):  600-603.  doi:10.3969/j.issn.1000-1093.2004.05.021

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Based on the cylinder method, a mathematical model for underwater passive sound reflectors was set up. The study sets its goal on the relationship of target strength of cylinder and the acoustic param?eters of materials when the frequency varies from 500Hz to 20kHz. Through simulation, the best parame- ters of passive sound reflectors were obtained. Its results give a basis for sound, reflector design.

Common Information Model for Military Electronic Information System Management

1:Li Hang,Wang Guangxing;2:Pan Chengsheng, Liu Yong,

2004, 25(5):  604-608.  doi:10.3969/j.issn.1000-1093.2004.05.022

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No conformed specification exist in describing the supervision of resources of military electron?ic information systems. As a trend, more and more business standards and protocols come to be used in mil?itary management. Aimed at the specialty of military systems, an information model for military supervi?sion based on common information model (CIM) was put forward. The moael is provided to establish a common conceptual framework for a description of the military managed environment. According to map?ping data types in SNMP,DMI and CMIP，the information model can have compatibility for other proto?cols. Through examples, the MOF definition for managed objects and mapping ot CIM to XML were illus?trated.

Effect of Stimulated Raman Scattering in Wave Division Multiplex Systems with Er Doped Fiber Amplifier

Li Yanping, Fang Juanni, Wang Shengkun

2004, 25(5):  609-612.  doi:10.3969/j.issn.1000-1093.2004.05.023

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Investigates the influence of stimulated Raman scattering (SRS) on WDM systems with ED?FA. The energy in the short-wave channel is transferred to the long-wave channel by reason of SRS. Thus the short-wave channel is attenuated and the long-wave channel amplified，whereas the chief influence is on the former channel. So the error bit ratio of channel I is discussed. A theoretical model is presented based on probability and perturbation theory, as well as characteristics of the system for evaluation of error bit rate degradation. In term oi tne model, relation figure between EBR and the number of amplifiers, EBR and the interval among channels, EBR and the input optical power, EBR and the number of channels are shown. The paper analyses how SRS limits tne input optical power and the number of EDFA，as well as the interval of channels from the relation figures. The results demonstrate that system parameters must be limited m longer-distance wave division multiplex systems with EDFA communication system. Reasonable channel interval and channel capability should be decided integrally considering the error bit rate.

A Semi-Fragile Video Watermarking Scheme Based on Content Features

Lei Hongyu, Dai Yuewei, Wang Zhiquan,Wang Jinshen

2004, 25(5):  613-618.  doi:10.3969/j.issn.1000-1093.2004.05.024

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A feature coding scheme based on tlie content of MPEG-エ /11 video was proposed. The basic logic of the scheme is to use partial energy relation between groups of 8 X 8 DCT block to produce related feature code. A semi-fragile video watermarking scheme combines correctly the content based feature coding with the watermarking scheme. The feature code has the semi-fragile，property, meaning that it is robust to the acceptable ‘content preserving? modifications but sensitive to the * content changing，tampering. The lower DCT region is used to form the feature codes while the higher one is used to embed watermarks. Experimental results on video objects demonstrate the effectiveness of the scheme.

Comprehensive Reviews

Electric Drive Systems in Armored Tracklayer Vehicles

Yan Nanming, Ma Xiaojun, Zang Kemao

2004, 25(5):  619-623.  doi:10.3969/j.issn.1000-1093.2004.05.025

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Armored tracklayers with electric drives have many of their merits when compared with me?chanical drive vehicles. It has become an important direction of tracked combat vehicles development. The paper gave a brief introduction as to the status and trends, and lays out the constitution and basic forms of electric drive systems in armored tracklayers. References were given to developments of electric drive sys?tems in cars, giving interrelated achievements abroad. Four kinds of pivotal technology were expounded and some view points for reference were presented.

Passive Acoustic Radar for the Detection of Supersonic Cruise Missiles

Xiao Feng

2004, 25(5):  624-629.  doi:10.3969/j.issn.1000-1093.2004.05.026

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As a necessary complement to radar, passive acoustic radar was presented, as a positive tactic for detecting cruise missiles. Acoustic characteristics of supersonic flying projectiles in diverse shapes, were expounded via experimental study. It was pointed out that simulation experiments could be implemented using bullets or shells instead of cruise missiles. Based on theoretical analysis and experiments, the “acoustic fingerprint” character of cruise missile was illustrated afterwards, to identify it in strong noise. After estab?lishing a mathematical model of location, the technique of acoustic embattling is utilized to resolve the prob?lem of confirmation the time of forewarning，considering the fact that the velocity of sound is much lower than that of light, !hereby, the whole system of passive acoustic radar for the detection of supersonic cruise missile was formed.

Experimental Techniques and Analysis

Antistatic Property of Short-Circuiting Card in Protecting Unguided Rocket

Wu Zhancheng, Wang Shuping, Hu Xiaofeng, Liu Shanghe

2004, 25(5):  630-633.  doi:10.3969/j.issn.1000-1093.2004.05.027

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Static resistances with and without short-circuiting card were measured. The method used in testing the systematic resistance with the short-circuiting card using pulse-current generator was put for?ward. The experiment shows that the dynamic resistance is very small (less than 30mf2) and that the anti?static property of the unguided rocket is obviously improved.

Research Notes

Combined Phase Modulation and Pulse Position Modulation Fuze Based on Pseudo-Random Code

1：Liu Jibin,Yang Fang；2： Zhao Huichang

2004, 25(5):  634-637.  doi:10.3969/j.issn.1000-1093.2004.05.028

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A method of generating pseudo-random PPM signal and PPM pseudorandom code was brought forward. On tms basis, a new combined fuze—combined phase modulation and pulse position mod?ulation fuze based on pseudorandom code was introduced. Principle of the combined fuze was illustrated and the formula of signals in each stage was deduced. By analyzing the performance of the combined fuze, it is proved that the combined fuze has its advantageous general performance，and in particular its strong charac- teristics of J^CCM is given.

Space-Time Adaptive Filter with Recursive Algorithm

1：Tao Jianwu；2：Chang Wenxiu, Shi Yaowu

2004, 25(5):  638-640.  doi:10.3969/j.issn.1000-1093.2004.05.029

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For use with AEW radar, a new space-time adaptive filter with recursive algorithm was pro?posed. The recursive algorithm with M-LMS is adopted; calculation of the covariance matrix of clutter and its reverse matrix are not necessary, while the degree of freedom in the system is kept. Simulations were presented to show that the filter is characterized by rapidly convergent rate, good performance of tilter, and convenient implementation in real time.

Fast Acquisition and Tracking for the Signals of Low Earth Orbit Satelite DSSS Communication Based on Software Radio Platform

Yang Bo, Wang Yueke, Yang Jun, Gong Erling,Zhou Yongbin

2004, 25(5):  641-645.  doi:10.3969/j.issn.1000-1093.2004.05.030

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According to the signal synchronization of LE〇，s direct sequence spread spectrum (DSSS) communication, a method based on software radio platform was described. Using the planar search, code start point and carrier frequency were reached at the same time. In the continuous tracking, using the cor?relative re-conformation of matching filter, with the subdivision of frequency or phase, a multi-frame pro?cessing arithmetic for antトjamming was put forward. This arithmetic provides a good solution for the wide dynamic range of Doppler frequency and the code start point excursion. At the end of this article, test data and its analysis were provided, which can be of reference value for DSSS communication in low SNR envi?ronment ?

A New Method for Even Tranfering Resonance Range in Active Magnetic Bearings

1:Wang Tongyu ,Jiang Huilin;2:Jia Hongguang, Wu Yihui

2004, 25(5):  646-648.  doi:10.3969/j.issn.1000-1093.2004.05.031

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Active magnetic bearing (AMB) is a high performance and new type of bearing, having the ro?tor levitating in the air gap by the electromagnetic force. A new method for an even tranfering resonance range in the AMB was presented and analyzed in detail. Taking advantage of the active control system and the air gap between the rotor and stator, the bearing point was changed at the point of switching frequency and the formation of a double supporting structure, an even transition was attained. Simulation experiments show that the new methoa is feasible.

An Adaptive Workflow Model Supporting Dynamic Modification

1：Zhu Jinquan；2：Yuan Senmiao

2004, 25(5):  649-652.  doi:10.3969/j.issn.1000-1093.2004.05.032

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Supporting dynamic changes, the ability of dynamic modification and adaptability is required when workflow management systems are employed. Existing research work are all focused on some special changing issues. In this paper an adaptive workflow model supporting dynamic modification was given. The dynamic characteristics of workflow were analyzed from the points of view of time and process levels. In this model，the dynamic modification of process and activity was studied at the building and running level， and the data association rules and control association rules between process and process，activity and activity were taken into account, to solve the problem of correctness and consistency, so as to strengthen the adapt?ability of the system.

The State Feedback Ptof Bifurcation Control of Two Nonlinear System

1：Wang Baohua, Yang Chengwu；2：Zhang Qiang

2004, 25(5):  653-656.  doi:10.3969/j.issn.1000-1093.2004.05.033

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Hopf bifurcation theory was briefly presented. The state feedback Hopf bifurcation controllers with variable gains were designed for a Van der pol oscillator and a 2-D nonlinear system giving rise to sub- critical Hopf bifurcations. Lyapunov stability theorem is used to prove the validity of the controllers. The maximal characteristic of this state feedback Hopf bifurcation controller is that it is irrelevant to the parame?ter of the system and the controller can eliminate Hopf bifurcation and guarantee asymptotical stability. Simulation results show that the nonlinear system can obtain asymptotical stability. As a result, the state feedback can be designed to eliminate inherent Hopf bifurcation of a nonlinear system, yet not delaying bi-furcation, modifying the shape or type of a bifurcation chain, or introducing a new bifurcation at a prefer?able parameter value to enlarge the system s stability range.