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A novel LS-SVM control for unknown nonlinear systems with application to complex forging process

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Journal of central South University 2017年第11期24卷 2524-2531页

作者： FAN Bin LU Xin-jiang HUANG Ming-hui School of Mechanical and Electrical Engineering Central South University College of Mechanical and Electrical Engineering Hunan City University

A novel LS-SVM control method is proposed for general unknown nonlinear systems. A linear kernel LS-SVM model is firstly developed for input/output(I/O) approximation. The LS-SVM control law is then derived directly from this developed model without any approximation and assumption. It further proves that the control error is fully equal to the LS-SVM modeling error. This means that a desirable control performance can be achieved because the LS-SVM has been proven to have an outstanding modeling ability in the previous studies. Case studies finally demonstrate the effectiveness of the proposed LS-SVM control approach.

关键词： unknown system inverse control input/output approximation LS-SVM control linear kernel

Effect of Substrate and Annealing Temperatures on Mechanical Properties of Ti-rich NiTi Films

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Journal of Materials Science & Technology 2010年第11期26卷 961-966页

作者： A.Kumar S.K.Sharma S.Bysakh S.V.Kamat S.Mohan Defence Metallurgical Research Laboratory Department of Instrumentation Indian Institute of Science central Glass and Ceramics Research Institute

The effect of substrate and annealing temperatures on mechanical properties of Ti-rich NiTi films deposited on Si （100） substrates by DC magnetron sputtering was studied by *** films were deposited at two substrate temperatures viz.300 and 400 ℃.NiTi films deposited at 300 ℃ were annealed for 4 h at four different temperatures,i.e.300,400,500 and 600 C whereas films deposited at 400 ℃ were annealed for 4 h at three different temperatures,i.e.400,500 and 600 ℃.The elastic modulus and hardness of the films were found to be the same in the as-deposited as well as annealed conditions for both substrate *** a given substrate temperature,the hardness and elastic modulus were found to remain unchanged as long as the films were ***,both elastic modulus and hardness showed an increase with increasing annealing temperature as the films become *** results were explained on the basis of the change in microstructure of the film with change in annealing temperature.

关键词： NiTi thin film Annealing Nanoindentation

Kinetic study of LiMn2O4 in process of lithium intercalation

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Journal of central South University of Technology 2005年第Z1期12卷 72-75页

作者： XU Ming-fei LI Xing-hai CHEN Qi-yuan School of Metallurgical Science and Engineering Central South University Changsha 410083China School of Chemistry and Chemical Engineering Central South University Changsha 410083China School of Metallurgical Science and Engineering Central South University Changsha 410083China School of Chemistry and Chemical Engineering Central South University Changsha 410083China

Exchange current density of spinel LiMn2 O4 was studied by linear polarization. The relationship of the kinetic property with the structure of spinel LiMn2 O4 was investigated by studying the effect of the doping and surface coating on the kinetic properties of electrode material. The results show that the exchange current density of spinel LiMn2 O4 electrode increases with the increase of the amount for lithium intercalation at first, and then decreases. The maximal exchange current density appeares at the 80%-90% lithium intercalation. The similar phenomenon was observed on the doped spinel LiMn2 O4 electrode. Doping can enhance the exchange current density of spinel LiMn2 O4 material. However, the degree of the doping effect varies with the doped element varying. Surface coating can also enhance the exchange current density of spinel material, and the increment of value is higher than that of doped ones.

关键词： kinetic exchange current density spinel LiMr2O4 doping surface coating

Comparison of flow behaviors of near beta Ti-55511 alloy during hot compression based on SCA and BPANN models

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Transactions of Nonferrous Metals Society of China 2021年第6期31卷 1665-1679页

作者： Shuang-xi SHI Xiu-sheng LIU Xiao-yong ZHANG Ke-chao ZHOU State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Wuhan Research Institute of Materials Protection Wuhan 430030China Shenzhen Research Institute Central South UniversityShenzhen 518057China

The flow behavior of Ti-55511 alloy was studied by hot compression tests at temperatures of 973−1123 K and strain rates of 0.01−10 s^(−1).Strain-compensated Arrhenius(SCA)and back-propagation artificial neural network(BPANN)methods were selected to model the constitutive relationship,and the models were further evaluated by statistical analysis and *** stress−strain data extended by two models were implanted into finite element to simulate hot compression *** results indicate that the flow stress is sensitive to deformation temperature and strain rate,and increases with increasing strain rate and decreasing *** the SCA model fitted by quintic polynomial and the BPANN model with 12 neurons can describe the flow behaviors,but the fitting accuracy of BPANN is higher than that of *** cross-validation tests also confirm that the BPANN model has high prediction *** models are effective and feasible in simulation,but BPANN model is superior in accuracy.

关键词： Ti-55511 alloy flow stress Arrhenius constitutive equation back-propagation artificial neural network finite element

2D polyaniline with exchangeable interlayer fluid for fast and stable volumetric dual ion storage

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Journal of Energy Chemistry 2021年第3期30卷 587-594页

作者： Xiaochen Yang Jiaxing Liang Aditya Rawal Kefeng Xiao Yuan Pu Xiao Li Zhang Ruopian Fang Da-Wei Wang Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029China School of Chemical Engineering The University of New South WalesSydneyNSW 2052Australia nmr facility Mark Wainwright Analytical CentreThe University of New South WalesSydney 2052NSWAustralia Research Centre of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China School of Materials Science and Engineering Zhengzhou University450001China UNSW Digital Grid Futures Institute The University of New South WalesSydney 2052NSWAustralia

Two-dimensional(2D) layered materials are widely applied in energy devices including lithium-ion battery and supercapacitor due to their unique properties,such as tunable interlayer structure,numerous active sites,large aspect ratio versatile interlayer *** this work,2D layered tungstate acidlinked polyaniline(TALP) presented a fluid-in-solid structure,which allowed facile exchange of the interlayer fluid from moisture to conventional Li^(+) containing *** fast and stable dual ion storage(Li^(+) and PF_(6)^(-)),TALP demonstrates high-rate volumetric capacity(39 mAh cm_(-3) at 2000 mA g^(-1)) and good stability(2000 cycles at 200 mA g^(-1)) within the working potential window of 1.5-4.5 V versus Li^(+)/Li.

关键词： Tungsten acid-linked polyaniline 2D material Fluid-in-solid Lithium-ion capacitor Volumetric

Smart manufacturing of nonferrous metallurgical processes:Review and perspectives

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International Journal of Minerals,Metallurgy and Materials 2022年第4期29卷 611-625页

作者： Bei Sun Juntao Dai Keke Huang Chunhua Yang Weihua Gui School of Automation Central South UniversityChangsha 410083China Peng Cheng Laboratory Shenzhen 518000China

The nonferrous metallurgical(NFM)industry is a cornerstone industry for a nation’s *** the development of artificial technologies and high requirements on environment protection,product quality,and production efficiency,the importance of applying smart manufacturing technologies to comprehensively percept production states and intelligently optimize process operations is becoming widely recognized by the *** a brief summary of the smart and optimal manufacturing of the NFM industry,this paper first reviews the research progress on some key facets of the operational optimization of NFM processes,including production and management,blending optimization,modeling,process monitoring,optimization,and ***,it illustrates the perspectives of smart and optimal manufacturing of the NFM ***,it discusses the major research directions and challenges of smart and optimal manufacturing for the NFM *** paper will lay a foundation for the realization of smart and optimal manufacturing in nonferrous metallurgy in the future.

关键词： nonferrous metallurgical industry smart and optimal manufacturing online perception intelligent control operational optimiza-tion automation of knowledge-based work

Prediction of Al(OH)_3 fluidized roasting temperature based on wavelet neural network

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中国有色金属学会会刊：英文版 2007年第5期17卷 1052-1056页

作者：李劼刘代飞戴学儒邹忠丁凤其 School of Metallurgical Science and Engineering Central South University Changsha Engineering and Research Institute of Nonferrous Metallurgy

The recycle fluidization roasting in alumina production was studied and a temperature forecast model was established based on wavelet neural network that had a momentum item and an adjustable learning rate. By analyzing the roasting process, coal gas flux, aluminium hydroxide feeding and oxygen content were ascertained as the main parameters for the forecast model. The order and delay time of each parameter in the model were deduced by F test method. With 400 groups of sample data (sampled with the period of 1.5 min) for its training, a wavelet neural network model was acquired that had a structure of {7 211}, i.e., seven nodes in the input layer, twenty-one nodes in the hidden layer and one node in the output layer. Testing on the prediction accuracy of the model shows that as the absolute error ±5.0 ℃ is adopted, the single-step prediction accuracy can achieve 90% and within 6 steps the multi-step forecast result of model for temperature is receivable.

关键词：子波神经网络氢氧化铝硫化煅烧

Structure and Properties of Functionalized Polyfluorenone Containing Hetero Aromatic Side Chains

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Chinese Journal of Polymer Science 2014年第5期32卷 667-674页

作者： R.Venkatesan N.Somanathan N.Rajeswari Department of Printing Technology College of Engineering Guindy Anna University Polymer lab Central Leather Research institute

The optical properties of substituted fluorenones with diverse structures have been analyzed using molecular orbital calculations in order to understand the structure-property relations. Based on theoretical predictions, synthesis of some model compounds has been attempted. The experimentally obtained optical properties are in close agreement with the theoretically obtained results.

关键词： Conjugated polymer UV-Visible spectroscopy Band gap Structure and properties Molecular orbital calculations.

Imazaquin degradation and metabolism in a sandy loam soil amended with farm litters

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Journal of Environmental Sciences 2007年第9期19卷 1108-1113页

作者： WANG Hui-li LI Yan-yan WEI Guo-hui WANG Xue-dong Key Laboratory of Pesticide and Chemical Biology of Ministry of Education Central China Normal University Wuhan 430079 China

Irnazaquin applied in legume crops has a long residual time in soil, which often impacts safety of the susceptible crops. To increase safety of imazaquin application, two composted litters, bovine manure （BM） and chicken manure （CM）, were used to determine their effects on imazaquin environmental behavior by incorporating each kind of manure into the tested sandy loam soil at 10% （w/w）. The degradation of imazaquin in BM- and CM-amended soil was about 2.4 and 1.5 times, respectively, faster than that in unamended soil. The half-lives of imazaquin in BM-amended soil varied between 6.7 and 15.4 d over the temperature range of 20 to 40℃, and the degradation rate constant （k） increased by a factor of about 1.5 for every 10℃ change. Higher mix ratio did not significantly increase the degradation, and the optimal active degradation of imazaquin was observed approximately at the mix ratio of 10：1 of soil to BM. The different moisture levels had negligible effect on imazaquin degradation. In both unamended and BM-amended treatments, two metabolites were observed at 5, 10 and 30 d after treatment. One metabolite at retention time （RT） of 8.4 rain was identified as 2-（4- hydroxyl-5-oxo-2-imidazolin-2-yl） quinoline acid, originating from the loss of isopropyl group and hydroxylation at the 4-position of imidazolinone ring. The other at RT of 12.9 rain was identified as quinoline-2,3-dicarboxylic anhydride, resulting from detachment of imidazolinone ring and the forming of dicarboxylic anhydride. This finding suggested that the addition of farm litters into soil might be a good management option since it can not only increase soil fertility but also contribute to increase safety of imazaquin application to the following susceptible crops.

关键词： imazaquin farm litter enhanced degradation metabolite