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IBPSO-Based MUSIC Algorithm for Broken Rotor Bars Fault Detection of Induction Motors

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 48-57页

作者： Pan-Pan Wang xiao-xiao Chen Yong Zhang Yong-Jun Hu chang-Xin Miao School of Electrical and Power Engineering China University of Mining & Technology Xuzhou 221116 China School of Information and Control Engineering China University of Mining & Technology Xuzhou 221116 China

In spectrum analysis of induction motor current, the characteristic components of broken rotor bars（BRB） fault are often submerged by the fundamental component. Although many detection methods have been proposed for this problem, the frequency resolution and accuracy are not high enough so that the reliability of BRB fault detection is a ected. Thus, a new multiple signal classification（MUSIC） algorithm based on particle swarm intelligence search is developed. Since spectrum peak search in MUSIC is a multimodal optimization problem, an improved bare?bones particle swarm optimization algorithm（IBPSO） is proposed first. In the IBPSO, a modified strategy of subpopulation determination is introduced into BPSO for realizing multimodal search. And then, the new MUSIC algorithm, called IBPSO?based MUSIC, is proposed by replacing the fixed?step traversal search with IBPSO. Meanwhile, a simulation signal is used to test the e ectiveness of the proposed algorithm. The simulation results show that its frequency precision reaches 10-5, and the computational cost is only comparable to that of traditional MUSIC with 0.1 search step. Finally, the IBPSO?based MUSIC is applied in BRB fault detection of an induction motor, and the e ectiveness and superiority are proved again. The proposed research provides a modified MUSIC algorithm which has su cient frequency precision to detect BRB fault in induction motors.

关键词： MUSIC Multimodal Bare?bones particle swarm optimization Induction motors Broken rotor bars Fault detection

Active set strategy of optimized extreme learning machine

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Chinese Science Bulletin 2014年第31期59卷 4152-4160页

作者： xiao-Jian Ding Bao-Fang chang Science and Technology on Information Systems Engineering Laboratory School of Computer and Information Engineering Henan Normal University

Extreme learning machine(ELM)has been introduced as a simple and efficient learning approach for regression and classification *** the optimization point of view,optimized ELM is equivalent to SVM,but with less constraints in the optimization formulation and random ELM *** paper introduces an active set based optimized ELM approach to solve bound constrained optimization problem in a straightforward way,which operates on a small working set of variables at each ***,the constrained problem can be eventually solved by an unconstrained algorithm,and this enables us to establish a global convergence *** approach requires less time for quadratic programming solving and provides better generalization *** addition,the proposed approach with much smaller number of nonbound support values is significantly faster than SVM with active set strategy for large training data set.

关键词：优化配方学习机有效集策略约束优化问题支持向量机 ELM 学习方法应用程序

Cavitation erosion behavior of WC coatings on CrNiMo stainless steel by laser alloying

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International Journal of Minerals,Metallurgy and Materials 2009年第2期16卷 203-207页

作者： xiao-bin Zhang chang-sheng Liu xiao-dong Liu Jiang Dong Bo Yu School of Materials and Metallurgy Northeastern University Shenyang 110004 China School of Material Science and Engineering Chongqing Institute of Technology Chongqing 400050 China Shenyang Research Institute of Foundry Shenyang 110022 China

The WC powder was precoated on the surface of CrNiMo stainless steel and then made into an alloying layer by using the laser alloying technique. Phases in the layers were investigated by X-ray diffraction （XRD） analysis and surface morphologies after cavitation erosion were observed with the help of scanning electron microscopy （SEM）. The cavitation erosion behavior of the CrNiMo stainless steel and WC laser alloying layer in distilled water was tested with the help of ultrasonic vibration cavitation erosion equipment. The results showed that the thickness of the laser alloying layer was about 0.13 mm. The layer had a dense microstructure, metallurgically bonded to the substrate, and no crack had been found. The cavitation erosion mass loss rate of the laser alloying layer was only 2/5 that of the CrNiMo stainless steel. The layer had better cavitation resistance properties because of its metallurgical combination and the strengthening effects of the precipitate phases.

关键词： martensite stainless steel laser surface alloying cavitation erosion WC

Relationship between focal adhesion kinase and hepatic stellate cell proliferation during rat hepatic fibrogenesis

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World Journal of Gastroenterology 2004年第20期10卷 3001-3005页

作者： Hui-QingJiang xiao-LanZhang LiLiu chang-ChunYang DepartmentofGastroenterology TheSecondHospitalofHebeiMedicalUniversityShijiazhuang050000HebeiProvinceChina DepartmentofMedicine theArmedPoliceHospitalofHebeiProvinceShijiazhuang050081HebeiProvinceChina

AIM: To investigate the dynamic expression of focal adhesion kinase (FAK) protein and FAK mRNA in fibrotic rat liver tissue, and the relationship between FAK and hepatic stellate cell (HSC) ***: Rat hepatic fibrosis was induced by bile duct ligation (BDL). Histopathological changes were evaluated by hematoxylin and eosin staining, and by Masson's trichrome method. FAK mRNA in the rat livers was determined by reverse transcription-polymerase chain reaction (RT-PCR), and the distributions of FAK were assessed immunohistochemistrically. The number of activated HSCs was quantified after alpha smooth muscle actin (α-SMA) ***: With the development of hepatic fibrosis, the positively stained cells of α-SMA increased obviously, which were mainly resided in the portal ducts, fiber septa and perisinuses accompanied with proliferating bile ducts. The positively stained areas of the rat livers in model groups 1 to 4 wk after ligation of common bile duct (12.88±2.63%,22.65±2.16%, 27.45±1.86%, 35.25±2.34%, respectively)were significantly larger than those in the control group (5.88±1.46%) (P<0.01). The positive staining for FAK significantly increased, which was mainly situated in portal ducts, fiber septa and around the bile ducts, vascular endothelial cells and perisinusoidal cells. The expression of FAK was positively correlated with α-SMA expression(r=0.963, P<0.05). FAK mRNA expression was obviously up-regulated in the model groups compared to the control group. CONCLUSION: These data suggest that expressions of FAK protein and mRNA are greatly increased in fibrotic rat livers, which may play an important role in HSC proliferation and hepatic fibrogenesis.

关键词：支持激酶肝星形细胞分芽增殖期间老鼠肝纤维化

Capacitive Properties of the Binder-Free Electrode Prepared from Carbon Derived from Cotton and Reduced Graphene Oxide

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Chinese Journal of Chemistry 2017年第12期35卷 1844-1852页

作者： Wenhui Ma Yunzhen chang Gaoyi Han Yaoming xiao Dongying Fu Yahui chang Institute of Molecular Science Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province Key Laboratory of Chemical Biology and Molecular Engineering of Education Ministry Shanxi University Taiyuan Shanxi 030006 China lnstitute of Crystalline Material Key Laboratory of Materials for Energy Conversion and Storage of Shanxi Province Shanxi University Taiyuan Shanxi 030006 China

The binder-free composite films of reduced graphene oxide （rGO） and activated carbon derived from cotton （aCFC） have been fabricated and used as electrodes for electrochemical capacitors （ECs） to avoid the decrease of capacitive performance in traditional process caused by the additional binder. The optimal aCFC is prepared at 850 ℃ when the mass ratio of carbon and potassium hydroxide is 1 to 4. The optimal composite film prepared from the mass ratio of aCFC/GO = 2/1 exhibits porous structure, and has a specific surface area of 849.6 m^2·g^-1 and a total pore volume of 0.61 mL·g^-1. Based on the two-electrode system testing in 6.0 mol/L KOH electrolyte, the optimal composite has specific capacitance of about 202 Fog-1, 374 mF·cm^-2 and 116 F·cm^-3 in terms of mass, area and volume, and shows excellent rate capability and good cyclic stability （91.7% retention of the initial capacitance after 5000 cycles）. Furthermore, the assembled solid-state ECs by using KOH/polyvinyl alcohol as electrolyte show good mechanical stability and capacitive performances after repeated bending cycles. It is proved that this method is effective to fabricate binder-free electrodes for ECs and will open up a novel route for the reuse of waste cotton.

关键词： binder-free graphene activated carbon flexible film electrochemistry

Parameter Dependence of Stable Manifolds for Nonuniform (μ, ν)-dichotomies

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1111-1130页

作者： Ji Min ZHANG Meng FAN xiao Yuan chang College of Mathematics Jilin University School of Mathematical Sciences Heilongjiang University School of Mathematics and Statistics Northeast Normal University School of Applied Sciences Harbin University of Science and Technology

We construct stable invariant manifolds for semiflows generated by the nonlinear impulsive differential equation with parameters x＇= A（t）x ＋ f（t, x, λ）, t≠τi and x（τ＋i） = Bix（τi）＋ gi（x（τi）, λ）, i ∈ N in Banach spaces, assuming that the linear impulsive differential equation x＇= A（t）x, t≠τi and x（τ＋i） = Bix（τi）, i ∈ N admits a nonuniform （μ, ν）-dichotomy. It is shown that the stable invariant manifolds are Lipschitz continuous in the parameter λ and the initial values provided that the nonlinear perturbations f, g are sufficiently small Lipschitz perturbations.

关键词： Stable invariant manifolds nonuniform ( μ ν )-dichotomies impulsive differential equations

Role of Insulin-like Growth Factor II Receptor in Transdifferentiation of Free Silica-induced Primary Rat Lung Fibroblasts

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Biomedical and Environmental Sciences 2013年第12期26卷 979-985页

作者： HAO chang Fu LI xiao Fang YAO Wu Department of Occupational Health and Occupational Disease College of Public Health Zhengzhou University

Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured. A transdifferentiation model of primary rat lung fibroblasts was induced by free silica. Levels of a-SMA protein, IGF-liR protein and mRNA were measured by immunocytochemistry, Western blot and RT-PCR, respectively. Lung fibroblasts were treated with Wortmannin. Results The expression levels of a-SMA concentration and decreased after Wortmann and IGF-IIR increased with the increasing free silica n was used. Conclusion The IGF-IIR plays an important role in free silica-induced transdifferentiation of primary rat lung fibroblasts.

关键词： Transdifferentiation Lung fibroblasts Insulin-like growth factor II receptor Silicosis

Relationship of quantitative structure and pharmacokinetics in fluoroquinolone antibacterials

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World Journal of Gastroenterology 2007年第17期13卷 2496-2503页

作者： Die Cheng Wei-Ren Xu chang-xiao Liu Department of Pharmaceutical Engineering Schoolof Chemical Engineering and Technology Tianjin UniversityTianjin 300072 China National KeyLaboratory of Pharmacokinetics and Pharmacodynamics TianjinInstitute of Pharmaceutical Research Tianjin 300193 China

AIM： To study the relationship between quantitative structure and pharmacokinetics （QSPkR） of fluorocluinolone antibacterials.METHODS： The pharmacokinetic （PK） parameters of oral fluoroquinolones were collected from the literature. These pharmacokinetic data were averaged, 19 compounds were used as the training set, and 3 served as the test set. Genetic function approximation （GFA） module of Cerius2 software was used in QSPkR analysis.RESULTS： A small volume and large polarizability and surface area of substituents at C-7 contribute to a large area under the curve （AUC） for fluoroquinolones. Large polarizability and small volume of substituents at N-1 contribute to a long half life elimination.CONCLUSION： QSPkR models can contribute to some fluoroquinolones antibacterials with excellent pharmacokinetic properties.

关键词： Quantitative structure pharmacokinetic relationship Genetic function approximation Fluoro-quinolones Elimination half life

Genetic Analysis of Yield and Its Components of *** Hybrids Using Resynthesized Rapeseed Lines

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Agricultural Sciences in China 2009年第11期8卷 1286-1292页

作者： ZHAO Yong-guo xiao Ling LU chang-ming Oilcrops Research Institute Chinese Academy of Agricultural Sciences Wuhan 430062 P.R. China Graduate School Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

Resynthesized rapeseeds obtained by crossing the diploid parents Brassica rapa and Brassica oleracea have significant potential in hybrid breeding because of their higher genetic basis compared with Brassica napus cultivars. In this study, an 8 × 8 complete diallel experiment using four B. napus cultivars （BN） and four resynthesized rapeseed lines （RS） as parents was designed to study heterosis and genetic inheritance for yield components. The results showed that heterosis for yield per plant, the number of pods per plant and number of seeds per pod were high, with means 32.77, 24.49 and 15.71%, respectively. Diallel analysis showed that both additive and dominant effects were significant for yield and yield components. All traits, except for 1 000-seed weight, were significant for bl mean squares and exhibited directional dominance. Dominant genes had positive effects on yield per plant, pods per plant and 1000-seed weight, and negative effects on seeds per pod （r=-0.86, -0.62, -0.41, and 0.47, respectively）. Narrow-sense heritability for yield per plant, pods per plant, and 1 000-seed weight and seeds per pod were 66, 31, 46 and 78% for the four traits, respectively. The Fl hybrids showed considerable yields compared to B. napus cultivars when B. napus cultivars and resynthesized rapeseeds were used as parents （NR hybrids）, with many more pods per plant and lower seeds per pod compared with the rapeseed cultivars, indicating that the resynthesized rapeseed may be applicable in current hybrid breeding programs.

关键词： diallel analysis heterosis yield components resynthesized rapeseed