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A linear ridgelet network approach for fault diagnosis of analog circuit

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Science china(information Sciences) 2010年第11期53卷 2251-2264页

作者： XIAO YingQun& HE YiGang college of electrical and information engineering, Hunan university, Changsha 410082, china college of electrical and information engineering Hunan University Changsha China

A linear ridgelet network combining ridgelet, linear term and the standard feed-forward neural network used for diagnosing the faults of analog circuit is constructed, and a training algorithm based on the steepest gradient descent method and momentum method for this network and the procedure for diagnosing these faults are proposed. The resulting linear ridgelet network can learn more rapidly from training samples and handle more effectively the complicated fault information of circuit under test than wavelet network and ridgelet network, classifying these faults effeciently and correctly and achieving a high classification accuracy. The simulation results demonstrate the effectiveness of this approach.

关键词： fault diagnosis of analog circuit ridgelet linear ridgelet network wavelet packet decomposition

Surrogate model-assisted interactive genetic algorithms with individual’s fuzzy and stochastic fitness

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控制理论与应用（英文版） 2010年第2期8卷 189-199页

作者： Xiaoyan SUN, Dunwei GONG (School of information and electrical engineering, china university of Mining and technology, Xuzhou Jiangsu 221116, china) School of information and electrical engineering China University of Mining and Technology Xuzhou Jiangsu China

We propose a surrogate model-assisted algorithm by using a directed fuzzy graph to extract a user’s cognition on evaluated individuals in order to alleviate user fatigue in interactive genetic algorithms with an individual’s fuzzy and stochastic fitness. We firstly present an approach to construct a directed fuzzy graph of an evolutionary population according to individuals’ dominance relations, cut-set levels and interval dominance probabilities, and then calculate an individual’s crisp fitness based on the out-degree and in-degree of the fuzzy graph. The approach to obtain training data is achieved using the fuzzy entropy of the evolutionary system to guarantee the credibilities of the samples which are used to train the surrogate model. We adopt a support vector regression machine as the surrogate model and train it using the sampled individuals and their crisp fitness. Then the surrogate model is optimized using the traditional genetic algorithm for some generations, and some good individuals are submitted to the user for the subsequent evolutions so as to guide and accelerate the evolution. Finally, we quantitatively analyze the performance of the presented algorithm in alleviating user fatigue and increasing more opportunities to find the satisfactory individuals, and also apply our algorithm to a fashion evolutionary design system to demonstrate its efficiency.

关键词： Interactive genetic algorithms User fatigue Surrogate model Directed fuzzy graph Fuzzy entropy

MOTION ANALYSIS AND DESIGN OF ACCUMULATOR FOR HYDRAULIC ROCK DRILL

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中国有色金属学会会刊：英文版 1996年第2期6卷 148-151页

作者： Liu Shixun(college of Mechanical and electrical engineering, Central South university of technology, Changsha 410083) college of Mechanical and electrical engineering Central South University of Technology Changsha 410083 China

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关键词： hydraulic accumulator diaphragm service life stretching ratio parameter design,motion analvsis

Adaptive interactive genetic algorithms with individual interval fitness

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Progress in Natural Science:Materials International 2008年第3期18卷 359-365页

作者： Dunwei Gong , Guangsong Guo, Li Lu, Hongmei Ma School of information and electrical engineering, china university of Mining & technology, Xuzhou 221008, china School of information and electrical engineering China University of Mining & Technology Xuzhou 221008 China

It is necessary to enhance the performance of interactive genetic algorithms in order to apply them to complicated optimization prob- lems successfully. An adaptive interactive genetic algorithm with individual interval fitness is proposed in this paper in which an indi- vidual fitness is expressed by an interval. Through analyzing the fitness, information reflecting the distribution of an evolutionary population is picked up, namely, the difference of evaluating superior individuals and the difference of evaluating a population. Based on these, the adaptive probabilities of crossover and mutation operators of an individual are presented. The algorithm proposed in this paper is applied to a fashion evolutionary design system, and the results show that it can find many satisfactory solutions per generation. The achievement of the paper provides a new approach to enhance the performance of interactive genetic algorithms.

关键词： Optimization Genetic algorithm Interaction Interval Probability of genetic operator

Parameter identification theory of a complex model based on global optimization method

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Science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1722-1732页

作者： QU Jie1, JIN QuanLin2 & XU BingYe3 1 college of Automotive engineering, South china university of technology, Guangzhou 510640, china 2 Beijing Research Institute of Mechanical and electrical technology, Beijing 100083, china 3 Department of engineering Mechanics, Tsinghua university, Beijing 100084, china college of Automotive engineering South China University of Technology Guangzhou China Beijing Research Institute of Mechanical and electrical technology Beijing China Department of engineering Mechanics Tsinghua University Beijing China

With the development of computer technology and numerical simulation technology, computer aided engineering (CAE) technology has been widely applied to many fields. One of the main obstacles, which hinder the further application of CAE technology, is how to successfully identify the parameters of the selected model. An elementary framework for parameter identification of a complex model is provided in this paper. The framework includes the construction of objective function, the design of the optimization method and the evaluation of the identified results, etc. The parameter identification process is described in this framework, taking the parameter identification of the superplastic constitutive model considering grain growth for Ti-6Al-4V at 927°C as an example. The objective function is the weighted quadratic sums of the difference between the experimental and computational data for the stress-strain relationship and the grain growth relationship; the designed optimization method is a hybrid global optimization method, which is based on the feature of the objective function and incorporates the strengths of genetic algorithm (GA), the Levenberg-Marquardt algorithm and the augmented Gauss-Newton algorithm. The reliability evaluation of parameter identification result is made through the comparison between the calculated and experimental results and between the theoretical values of the parameters and the identified ones.

关键词： constitutive model parameter identification theory inverse analysis global optimization

Relations between thickness of UHMWPE’s wear debris and positive pressure of tribological system

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Chinese Science Bulletin 2008年第9期53卷 1435-1443页

作者： LIU HongTao1,2,3 & GE ShiRong1,3 1 Institute of Tribology and Reliability engineering, china university of Mining & technology, Xuzhou 221116, china 2 college of Mechanical and electrical engineering, china university of Mining & technology, Xuzhou 221116, china 3 Biotribology Center, State Key Laboratory of Tribology, Xuzhou 221116, china Institute of Tribology and Reliability engineering China University of Mining & Technology Xuzhou China college of Mechanical and electrical engineering China University of Mining & Technology Xuzhou China Biotribology Center State Key Laboratory of Tribology Xuzhou China

MiaoXAM2.5X-50X Ultrahigh Precision Surface 3D Profiler is introduced to research the relations be- tween thickness of UHMWPE’s wear debris and positive pressure of tribological system. Research re- sults show that thickness of wear debris owns evident classification, and the first grade thickness math model and the second grade thickness math model are built. By the second grade thickness math model, the true force condition in the tribological system can be gotten, and the model can be used as a tool to modify simulating parameters of the tribological system, and it is an important inspecting method to the airtight system which cannot be examined in real time. The first grade thickness math model can describe the true working load and surface condition of work piece in the tribological sys- tem, and is an effective description method for the running condition of frictional pairs. The research results at different lubricating conditions testify the relations between thicknesses of wear debris and positive pressure of the tribological system. The fractal relation between maximal thickness of wear debris and positive pressure is discussed. The conceptions of the immutability principle and charac- teristic granularity of wear debris thickness are brought forward and discussed. In conclusion, as a stable tribological parameter owning mechanical theory basis, wear debris thickness will play an im- portant part in fault diagnosis, especially for the airtight system such as artificial joint.

关键词：摩擦学磨损面厚度分形数学模型

Stability of impulsive stochastic functional differential systems in terms of two measures via comparison approach

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Science china(information Sciences) 2012年第6期55卷 1313-1322页

作者： YAO FengQi 1,2 & DENG FeiQi 1 1 Institute of System engineering,South china university of technology,Guangzhou 510640,china 2 School of electrical engineering and information,Anhui university of technology,Maanshan 243032,china Institute of System engineering South China University of Technology Guangzhou China School of electrical engineering and information Anhui University of Technology Maanshan China

Comparison principles for general impulsive stochastic functional differential systems are *** the comparison principles and the theory of differential inequalities,stability and instability,involving two measures,of impulsive stochastic functional differential systems are *** stability and instability criteria are obtained,and two examples are also given to illustrate our results.

关键词： stochastic systems impulsive functional differential systems comparison principle stability in terms of two measures instability

Relationship between Multi-Phase Formation and Molecular Structure for Liquid Crystal System

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Journal of Wuhan university of technology(Materials Science) 2005年第3期20卷 11-13页

作者：李振新 Biomedical Materials and engineering Centre Wuhan University of Technology Department of Life Science and technology Xinxiang Medicine CollegeXinxiang 453003 China

4 mechanical model of liquid crystals （ LCs ） was used to explain the phase formation and thermal properties . The LC plusses in the model are micro- machine systems consisting of an ensemble of molecular rotors, and some dynamie parameters in a semi-experiment molecular orbit method. A novel explanation on the multi-phase formation of LC system is obtained. It is found that the value of the critical rotational velueity is a key parameter for the characterization of each homologous series. The dipole moment of the molecules was also discussed.

关键词： liquid crystal phase dynamic molecular structure

Improving anti-sulfur performance of methane sensors by new vectors and active components

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Mining Science and technology 2010年第6期20卷 913-916页

作者： WANG Ying, TONG Minming, ZHANG Tao School of information and electrical engineering, china university of Mining & technology, Xuzhou 221008, china School of information and electrical engineering China University of Mining & Technology Xuzhou 221008 China

Conventional Pd/γ-A12O3 methane sensors are easily poisoned in a sulfur-containing atmosphere, with a subsequent decrease in sensitivity and the working life of methane sensors. We mainly investigated the effect of nanotechnology and a cerium co-catalyst on the stability and anti-sulfur performance of methane sensors. In our experiment, an anti-sulfur methane sensor was prepared by immersing cerium-containing γ-alumina nanometer elements into a Pt-Pd bimetallic nanometer catalyst. The experi- ment about the sensitivity and stability performance of different catalytic methane sensors indicate that sensitivity, decreased by catalyst sulfur poisoning, is improved significantly by adding cerium to the vector. As well, the long-term operational stability of methane sensors increased significantly.

关键词： Cerium anti-sulfur stability sensitivity