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Table of Content

    25 May 2005, Volume 33 Issue 5
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    Fitness Function for Evolutionary Learning of Predictive Association Rules
    2005, 33(5):  1-6. 
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    In order to improve the predicted accuracy of the classification based on genetic algorithm,the fitness functions for evaluating the rule equMity are discussed in this paper.A fitness function based on a weighted sum of confidence and suppo~ is then proposed,which can substitutes the traditional fitness function based on sensitivity and specificity.Both the theoretically an alytical an d the experimental results show that the propo sed fitness function has a greater advantage in the evolutionary search of predictive association rules over the traditional one,and is helpful to the improvement of the machine learning based on genetic algorithm.

    Adaptive Fuzzy Control of Milling Process Based on Fieldbus
    Lai Xing-yu Ye Bang-yan Yan Chun-yan Li Wei-guang
    2005, 33(5):  7-10. 
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    Aiming at the nonlinearity,time-variability and uncertainty of the milling process,a scheme of the adap-five fuzzy control for the milling process based on the fieldbus is presented by considering the characteristics of fuzzy control and Profibus.A fuzzy controller with self-tuning output scaling factor and control rule is then designed and applied to the on.line control of the milling force with variable cutting parameters.Simulated results show that the
    proposed scheme solves the problems existing in the conventional fuzzy control,namely,slow response and weak ro-bustness,and is of quicker response,better real-time feasibility and stability.It can adaptively aajust the feedrate online tiU achieving a constan t milling force approaching the reference force in varied cutting conditions.thus im-proving the machining eficiency and protecting the tool.

    Impulsive Control of a Class of Nonlinear Time·Delay Diferential Systems
    Liu Xiu-xiang Xu Bu-gong
    2005, 33(5):  11-14. 
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    The aim of this paper is to investigate the problem of impulsive control of a class of nonlinear time-delay diferential systems x'=f(x( (t))+g( (t-τ )).In the investigation,the definitions for impulsive exponential stabilization and periodically impulsive exponential stabilization are first presented.The suficient conditions for these two kinds of stab ilizations are then obtained by constructing appropriate Lyapunov functions.Moreover,the design methods with simple and linear impulsive control functions that only depend on the system parameters are presented.Numerical exam ples are given to illustrate the proposed method.

    Necessary and Sufi cient Condition for Mean-Square Stability of Linear Stochastic System with Distributed Parameter
    Song Ya-nan Deng Fei-qi Luo Qi Yang Yi-min
    2005, 33(5):  15-18. 
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    On the basis of the new mathematical description of the linear stochastic system with distributed pa-rameter,the corresponding definition of mean-square stability is given.Moreover,by transferring partial dife-rential equ ations into ordinary diferential equations an d considering the boundary condition an d Divergence Theolea-the conditions for the stab ility of partial diferential equ ations aTe presented,which aTe based on the stable
    conditions of ordinary diferential equ ations.Thus,the necessary an d suficient condition for the mean.square stability of the linear stochastic system with distributed parameter is obtaindd.Simulations are finally presented to verify the correctness of this research.

    Modified SVM and Its Application to Time Series Forecasting
    Feng Guo-he Zhu Si-ming
    2005, 33(5):  19-22. 
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    As the forecasting of a huge-size financial time series by training a standard SVM (Suppo~Vector Machine) will result in slow training speed and large memory spending,a decomposition-cooperation-weighted SVM regression is put forward and used to predict the stock index.In the proposed method,a large specimen set is de-composed into several subsets,and the SVMs in diferent subsets are independently extracted.According to the im-portance of the obtained SVMs,diferent error punishment degrees are obtained. Compared with the traditional SVM ,the propo sed method greatly speeds up the training process with almost the same precision.

    Softwae Development for Form Grinding of Gear Dies
    Zhou Yu-shan Shao Ming Min Hao-nian
    2005, 33(5):  23-25,47. 
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    In order to improve the accuracy of powder metallurgy gears,a numerical simulation method to calculate the profiles of grinding wheels for CNC (Computerized Numerical Control)was put forward,and the software for the profile calculation and machining of the grinding wheels was developed.A tooth-grinding experiment was then perform ed.Th e experimental results indicate that the proposed method is of simplicity an d rational data construction,which call be used to calculate any kind of gear shape.Th e developed software can be used to calculate the profiles of grinding wheels with any shape,such as spur gears and helical gears,to an alyze the grinding error to op-timize the grinding parameters,an d to create the wheel-dressing program and the gear-grinding program . The resuits of grinding experiment also show that the proposed software is feasible an d precise enough to meet the require-ments in the form grinding of gear dies.

    Design Knowledge Modeling Based on Ontology
    Zhang Dong-min Liao Wen-he Hu Jian Guo Yu Cheng Xiao-sheng Huang Ye
    2005, 33(5):  26-31. 
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    This paper investigates the knowledge modeling for the purpose of supporting the management and reuse of design knowledge,focusing on the management of design knowledge.Then,a management framework of design knowledge is proposed,which consists of three parts:the acquisition of design knowledge from all kinds of know-ledge sources,the knowledge modeling and the design knowledge retrieval.A method for design knowledge mode-ling based on ontology is then studied,which includes the definition of the ontology ,the establishment of the design knowledge base and a multi-view strategy of design knowledge retrieval.Moreover,the advan tag es of the mod eling of design knowledge based on ontology are discussed.On this basis,a knowledge-management tool is developed to support the production design .

    Profile Reconstruction Based on Dense Data Points in Reverse Engineering
    Tan Chang-bai Zhou Lai-shui An Lu-ling Peng Yu-yo
    2005, 33(5):  32-37. 
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    The reconstruction of such features as protrusion, pocket, extrusion and revolution depends on the re-construction the section profiles describing the feature shapes. As being dense and out-of-order, the collected data points cannot be directly parameterized and fitted by sp ine curve after the profile sketch p lane is determined. This paper addresses the p rofile reconstruction based on dense data points. In addition, a novel app roach is proposed. By this app roach, the“thick boundary”of the section p rofile is firstly extracted in the p rofile sketch p lane, and the obtained data points are then thinned and parameterized, thus imp lementing the reconstruction of the section profilerep resented by the B-spline. Experimental results prove that the proposed method can effectively reconstruct the profileswith the above-mentioned features.

    Analyses of Harmonic Torque and Circular Current in the Stator Winding of Brushless Doubly-Fed Machines
    Yang Xiang-yu Yang Jin
    2005, 33(5):  38-42. 
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    A harmonic equivalent circuit of BDFM (Brushless Double-Fed Machine)is proposed based on the arialysis of the magnetic field distribution of BDFM and the analysis of the harmonic magnetic filed reciprocity among the stator power winding,the stator control winding and the rotor winding.The creation of the harmonic torque and its influence on the operation performance of BDFM ale then analyzed.Moreover,the induction voltage in the stator
    windings resulting from the harmonic magnetic field of the induction current in the rotor winding is analyzed,and the reason for creating the circular curent in a parallel branch of stator windings are presented,thus a theoretical foundation for the design and harmonic analysis of BDLM being laid.

    Remote Monitor and Control Technology and Its Implementation for Photovoltaic Systems
    2005, 33(5):  43-47. 
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    Several remote monitor and control schemes with wide applicability in photovoltaic systems are summarized,meanwhile their practical principles ale given.On this basis,a practical remote monitor an d control system applied to photovohaic systems based on 485 bus and Internet technology is developed,which call timely monitor the ope rating states of the systems.The system includes terminal adapter,main computer and remote monitoring
    and controlling computers,which realized remote monitor and control by gateway server software and Internet network.The running results of the system show that the scheme is feasible.

    Workflow Model for Government Process
    Zheng Yi-qiang Guo He-qing Gao Wei
    2005, 33(5):  48-52,58. 
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    In order to set up a domainal ,flexible and standard workflow system appropriate to government.a go-vernment workflow system is put forward by combining the standard workflow model with the characteristics of go-vernment workflow applications.On this basis,a government workflow model is developed. The proposed medel is the extension of the standard workflow model,and it models government workflow through the government process meta-model,the government document meta-model and the government organ ization meta-model. with the modeled results storing in the form of government workflow description language. Moreover,based on the proposed govern-ment workflow model,the concepts of workflow design pattern and two-phase design are presented to simplify the design of government workflow.

    A Fast Algorithm Based on Sub-Pixel Motion for Super-Resolution Reconstruction of Image
    Du Juan Yu Ying-lin Xie Sheng-li
    2005, 33(5):  53-58. 
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    A novel algorithm based on sub-pixel motion for super-resolution reconstruction of images is proposed.In this algorithm,the 1-dimension statistical characteristic of the image is used twice.Firstly,the N frames of the image are divided into the motion field and the background field.Secondly,the motion-range of the pixels in the motion field is estimated. After the motion estimation an d motion compensation,N motion compe nsation im es afe
    obtained. At last,the data fusion technology is adopted to reconstruct a super-resolution image in combination of the information in the background.The experimental results show that the proposed algorithm is simper and less complex.Th e perform ance of this algorithm is better than the traditional bilinear interpolation method in minimum mean square error,signal-to-noise ratio and power sign al-to-noise ratio.

    Efectiveness of Chaotic Modulation to the EM I Suppresion of Off-Line Switching Converters
    Li Zhi-zhong Qiu Shui-sheng
    2005, 33(5):  59-63,73. 
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    CFMS(Chaotic Frequency Modulation Scheme)was realized by incorporating a Chua’S circuit into the pulsewidth modulator,which makes the switching frequency randomly vary with the chaotic signal.Th e efectiveness of CFMS to the EMI(Electromagnetic Interference)suppression of switching converters was then investigated.Moreover,the principle of the suppression of EMI noise by CFMS was analyzed and a simulation mod el for component-level circuits Was constructed.Simulated results show that,by means of CFMS,the peak value of the switching harmonics efectively decreases and the output voltage is slighfly influenced,indicating that CFMS is applicable to switching converters.

    Interconnection Among Information Platforms of City Traffic Management Departm ent
    Xu Jian-min Zhang Zi Hu Yu-cong Wu Yi-min
    2005, 33(5):  64-68. 
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    Aiming at the trafic management in Guangzhou,the problems existing in the information platforms respectirelv established by the Trafic Manag ement Committee and the Trafic Police Bureau of Guan gzhou are discussed.The thoughts of interconnecting the inform ation platforms of diferent trafic man agement departments and integrating diferent inform ation sources are also proposed.On this basis,all inform ation cooperating model of two distributed platforms and particular information organizing processes(including the collection,treatment,release aJ1d share of information)are presented,with a network scheme being put forward.Moreover,the phy‘ sical isolation technology is adopted to make the system eficient,secure and easy to realize an d expand. A thought of building an ATIS(Advance Traffic Information System)on the basis of interconnection and using XML technology to transform data form s is finally proposed.

    Design and Control Performance of the Self-Stable Controllable Underwater Towed Vehicle
    Wu Jia-ming Ye Jia-wei
    2005, 33(5):  69-73. 
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    In order to solve the problems of complicated control mechanism and unstable attitude of conventional controllab le underwater towed vehicles,a new self-stab le controllable underwater towed vehicle is proposed. The propo sed vehicle consists mainly of a controllab le depressing wing.a stable buoyant chamber an d a main body shaped like a rectangular wing.The trajectory and attitude of the vehicle are manipulated by the depressing force
    and turning moment provided by the active depressing wing and two stern thrusters.Th e results of the hydrodynamic control experiment for the proposed vehicle show that,with the above.mentioned design, the propo sed vehicle is of good stability in attitude and great eficiency in rapid trajectory manipulation,and the design of the control system of the vehicle is gready simplified.

    Extraction of Shark Cartilage Mucopolysaccharides by Enzym olysis and Their Composition Analysis
    Xiao Kai-jun Cai Miao-yan Guo Si-yuan Li Lin Wang Zhao-mei Luo Yuan-hong
    2005, 33(5):  74-77. 
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    The efects of the extraction times with one enzyme and the diferent treatments wit}l two enzymes on the extraction rate of mucopolysaccharides were investigated by carrying out orthogonal experiments.And the optimum hydrolysis conditions with trypsin and/or papain for the extraction of shark cartilage mucopolysaccharides were obrained.Moreover,the compositions of mucopolysaccharides extracted in diferent processes were analyzed by cellu-lose polyacetate strip and algarose gel electrophoresis.It can be seen from the experimental results that the degrada-tion rate and extraction rate for the extraction with tw o enzymes are higher than those for the extraction with one en-zyme.And the shark cartilage with papain·trypsin treatment can be hydrolyzed more efectively than that with tryp-sin·papain treatment,with a higher mucopolysaccharides extraction rate.Furthermore,the shark cartilag e mucopo-lysaccharides extracted with papain are purer than those extracted with trypsin.

    Enzymatic Hydrolysis of Silver Carp(Hypophthalmichthys Molitrix) PrOteins and Thermally Generated Meaty Flavor of the Hydrolysates
    Liu Tong-xun Li Yuan Zhao Mou-ming
    2005, 33(5):  78-82,86. 
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    This paper studies the enzymatic hydrolysis of silver carp(Hypophthalmichthys molitrix)proteins in various conditions and the Maillard reaction of the hydrolysates.The results show that:(1)silver carp proteins can be completely hydrolyzed by endo·-proteases an d followed by exo·-proteases into free amino ac ids an d small peptides;(2)the addition of 5%yeast(mass fraction,the sanle below)and 0.02% Nisin efectively remove the bitterness of the hydrolysates and prolong the hydrolyzation time;(3)delicious meaty flavor can be thermal-ly generated by the reaction of the hydrolysates with sugar,vitamins B1 and C,pepper,garlic powder an d LCys,andthefishyflavor completely disappears afterthe reaction;and(4)aftertheMailard reaction,12.6% of the free amino acids is lost,in which L-Cys,Glu and Asp greatly contribute to the meaty flavor ofthe hydro-lysates.Moreover,19 volatile compounds related to the meaty favor were determined by GC-MS,in which sul-furol possesses 54.74%(in mass)of the total volatile compounds.

    Gas-Phase Photocatalytic Degradation of Acetone by Using Nanoscale Titanium Dioxide
    Xiao Xin-yan Zhao Bao-shun Zhang Hui-ping
    2005, 33(5):  83-86. 
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    The photocatalytic degradation of gaseous acetone in a SGY-1 photoreactor was investigated by using nanoscale titanium dioxide(marked as P25)as the photocatalyst and glass as the substrate.Th e experimental re-suits show that(1)the degradation rate of acetone gradually increases with the increasing of 1)25 dosage in the re-action system first,and then slightly decreases after the P25 dosage reaches a certain value,(2)the degradation
    rate of acetone reaches the maximum value of 92.7% .after 1.5 h of the UV irradiation when P25 amounts to 460 mg on the surface of substrate,i.e.the surface density of P25 equals to 1 mg/cm2 ,(3)there is hardly photolysis in the absence of the photocatalyst,(4)both the existence of water in the reaction system and the increase in UV light intensity can enhance the degradation rate of gaseous acetone,and(5)the degradation rate of acetone re-markably decreases due to the partial deactivation of the identical photocatalyst being used six times.

    Module-Integrating Technology in Chemical Process Simulation and Its Application
    Wu Zhi-hui Cheng Hua-nong Li Xiu-xi Qian Yu
    2005, 33(5):  87-91. 
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    In order to satisfy the demands of chemical process simulation,an approach and the corresponding technology for integrating the defined modules of the user with the common simulation softwares were proposed based on the software integration technology.The proposed approach and technology were then applied to an industry,that is,simulating the solvent recovery system in the ketone-benzol-dewaxing process with Aspen Plus and neural network models.The results prove that the proposed approach an d technology are feasible an d can be used to solve some practical problems in chemical process simulation.

    Fuzzification and Relativity Analysis of Logistic Mappings
    Mo Hong Shi Song-quan
    2005, 33(5):  92-96. 
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    In order to compare the property of CDS(Conventional Dynamic System)corresponding to LDS(Lin-guistic Dynamic System),the logistic mapping Xn+1 =βxn (1-Xn ),β∈(0,4) is fuzzificated,whose stability,bi-furcation and chaotic property are then analyzed by means of the inner section mapping.The fuzzification of the lo-gistic mapping can not only retain the property of CDS but also simplify the description of system states an d huma-nize the outputs of the system.So,a theoretical foundation is laid for the development of intelligent computers in the future

    Pricing of Barrier Options with Time Dependance
    Chen Shu-min He Chun-xiong
    2005, 33(5):  97-100. 
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    The pricing of a new kind of option,barrier option,is discussed in this paper.The general discussion about barrier options usually concerns a relatively simple situation,that is,the option barrier is constant.However,the barrier actually changes with time.Because of this,the backward stochastic diferential equation and the equi-valent martingale are used to get a group offormulae for pricing the Europe an down·-and·-out call options with the hy-pothesis that the barrier is dependent on time.

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