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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

Fault diagnosis using a probability least squares support vector classification machine

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mining Science and technology 2010年第6期20卷 917-921页

作者： GAO Yang, WANG Xuesong, CHENG Yuhu, PAN Jie school of information and electrical engineering, china university of mining & technology, xuzhou 221116, china school of information and electrical engineering China University of Mining & Technology Xuzhou 221116 China

Coal mines require various kinds of machinery. The fault diagnosis of this equipment has a great impact on mine production. The problem of incorrect classification of noisy data by traditional support vector machines is addressed by a proposed Probability Least Squares Support Vector Classification Machine (PLSSVCM). Samples that cannot be definitely determined as belonging to one class will be assigned to a class by the PLSSVCM based on a probability value. This gives the classification results both a qualitative explanation and a quantitative evaluation. Simulation results of a fault diagnosis show that the correct rate of the PLSSVCM is 100%. Even though samples are noisy, the PLSSVCM still can effectively realize multi-class fault diagnosis of a roller bearing. The generalization property of the PLSSVCM is better than that of a neural network and a LSSVCM.

关键词： fault diagnosis probability least squares support vector classification machine roller bearing

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

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

Effect of Preparation Methods on Mechanical Properties of PVA/HA Composite Hydrogel

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Journal of Bionic engineering 2010年第3期7卷 235-243页

作者： Dekun Zhang~1, Junjie Duan~1, Dagang Wang~2, Shirong Ge~2 1. school of Materials Science and engineering, china university of mining and technology xuzhou 221116, P. R. china 2. school of Mechanical and electrical engineering, china university of mining and technology, xuzhou 221116, P. R. china school of Materials Science and engineering China University of Mining and Technology Xuzhou P. R. China school of Mechanical and electrical engineering China University of Mining and Technology Xuzhou P. R. China

Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA.

关键词： composite hydrogel HA contents freezing-thawing cycles static properties dynamic properties

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

Calculation of maximum ground movement and deformation caused by mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 562-569页

作者： LI Pei-xian1, 2, TAN Zhi-xiang1, 2, DENG Ka-zhong1, 2 1. Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping, china university of mining and technology, xuzhou 221116, china 2. Jiangsu Key Laboratory of Resources and Environmental information engineering, china university of mining and technology, xuzhou 221116, china Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China Jiangsu Key Laboratory of Resources and Environmental information engineering China University of Mining and Technology Xuzhou 221116 China

In order to know the maximum mining ground deformation of arbitrary surface point, directions of the maximum surface tilt, curvature,horizontal displacement and horizontal deformation caused by multi-working faces were deduced based on probability integral method. The distribution forms of surface deformations in all direction φ∈[0, 2π] were obtained and also equations of maximum deformations were given based on calculation of mining ground deformation in direction φ. A mining subsidence analysis system was developed with VB6.0. The system implements the probability integral mining subsidence prediction with direct integration method, and it can avoid errors of arbitrary shaped working face subdivision of traditional method, and accuracy of mining subsidence prediction can be improved with the direct integral method. The system implements the contour chart and profile chart and also data analysis automation by manipulation of the SURFER kernel function and it complements the defect of existing subsidence prediction software. Calculation of maximum deformations caused by multi-working faces mining in a coal mine of xuzhou, china was shown as application example. engineering application indicates that maximum deformation of mining ground surface can be calculated and analyzed by the system. The research provides a theoretical basis and calculation tool for mining subsidence prediction and analysis.

关键词： mining subsidence probability integral method movement and deformation system development

Description to wear debris boundaries by radar graph fractal method

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Chinese Science Bulletin 2007年第16期52卷 2285-2290页

作者： LIU HongTao1,2 & GE ShiRong1 1 Institute of Tribology and Reliability engineering,china university of mining & technology,xuzhou 221008,china 2 College of Mechanical and electrical engineering,china university of mining & technology,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

In this paper,radar graph fractal method is introduced to describe wear debris boundaries. Research results show that it is a nice way to describe wear debris boundaries. Since the longest axis is selected as the first coordinate axis,its center point selected as the center point of the radar graph,and the co-ordinate value of wear debris boundary selected as the measure parameter,the limitations existing in Yard fractal measure method can be avoided. For any wear debris,its radar graph fractal dimension value is one and only,and as the wear debris shape changes from round to strip,the radar graph fractal dimension value also changes from low to high,showing strong uniqueness and independence. Due to the fact that the researched wear debris is gotten in different wear states,the results also prove that radar graph fractal dimension value is correlated with frictional pairs work condition and wear state. Radar graph fractal method is compared with Yard fractal measure methods,and results show that ra-dar graph fractal dimension values gotten from different wear debris have enough value grads to avoid effect of errors,and provide higher sensitivity for wear debris shape. This paper also discusses the influencing factors for radar graph fractal method. With the increase of the decomposing degree value,the radar graph fractal dimension tends to keep stable at one certain value,showing the typical characteristic of the fractal theory. All this proves that radar graph fractal method is an effective description method for wear debris boundaries.

关键词：磨粒边界雷达图表分形法

Concurrent collision probability of RFID tags in underground mine personnel position systems

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mining Science and technology 2010年第5期20卷 734-737页

作者： JI Yuchu,XU Zhao,FENG Qinzhu,SANG Yuan school of information & electrical engineering,china university of mining & technology,xuzhou 221008,china school of information&electrical engineering China University of Mining&Technology Xuzhou 221008 China

According to the basic requirements of underground mine personnel position systems and the working characteristics of active RFID tags,we studied the cause of concurrent collision of RFID tags and leak reading probability,by means of theoretical analysis and *** result shows that the probability of wireless collision increases linearly with an increase in the number of *** probability of collision and leak reading can be reduced by extending the working period of the duty cycle and using a backoff *** a practical application,a working schedule for available labels has been designed according to the requirement of the project.

关键词： personnel position system RFID collision probability of RFID tag