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A new method for nondestructive damage identification of lattice materials

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Science China(Technological Sciences) 2009年第5期52卷 1293-1300页

作者： fang hui WANG TieJun MOE Key Laboratory for Strength and Vibration Department of Engineering MechanicsXi’an Jiaotong UniversityXi’an 710049China

This paper proposes vibration-based damage identification method,termed as substructure potential energy(SPE) method,which is capable of accurately estimating the damage magnitudes of multiple *** other existing damage severity estimation methods require the information of several unabridged modes of the structure,the new method utilizes only a few lower mode shapes of sub-structures measured from the damaged *** performance of the proposed method is compared with one existing damage detection method,using a set of numerical simulations on a lattice material beam based on synthetic data generated from finite element models.

关键词： lattice material damage identification strain energy

Neural Network-based Adaptive State-feedback Control for High-order Stochastic Nonlinear Systems

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自动化学报 2014年第12期40卷 2968-2972页

作者： MIN hui-fang DUAN Na School of Electrical Engineering & Automation Jiangsu Normal University

This paper focuses on investigating the issue of adaptive state-feedback control based on neural networks(NNs)for a class of high-order stochastic uncertain systems with unknown nonlinearities. By introducing the radial basis function neural network(RBFNN) approximation method, utilizing the backstepping method and choosing an approximate Lyapunov function, we construct an adaptive state-feedback controller which assures the closed-loop system to be mean square semi-global-uniformly ultimately bounded(M-SGUUB). A simulation example is shown to illustrate the effectiveness of the design scheme.

关键词：径向基函数神经网络状态反馈控制器随机非线性系统自适应高阶 Lyapunov函数非线性问题不确定系统

Bromate removal by gamma irradiation in aqueous solutions

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Nuclear Science and Techniques 2016年第1期27卷 44-49页

作者： Zhao-Lian Ye Xue-hui fang hui-Qi Hou College of Chemistry and Environmental Engineering Jiangsu University of Technology Department of Environmental Science and Engineering Fudan University

Bromate(BrO_3) is a disinfection by-product in drinking water, and its removal is very difficult especially at low levels.60 Co gamma rays were used to remove BrO_3in aqueous solution in this study. The effects of absorbed doses, BrO_3initial concentration, gas saturation, p H value and coexisting anions(Cl, NO 3, SO2 4and HCO 3=CO_3^(2 -))on BrO_3reduction were evaluated. After 4.0-k Gy irradiation of air-equilibrated solution of 30.7 lg/L BrO_3, the residual BrO_3was 8.3 lg/L, which is below the maximum contaminant level of drinking water. The BrO_3reduction rate increased with the dose, in the order of N2[ air [ O_2[ N_2O atmosphere under similar conditions. The results also show that high p H favored the BrO_3removal. According to the experimental results, it can be concluded that the efficiency of decomposing BrO_3by reactive species followed the order of e aq[ H [ HO_2 [ O_2. Coexisting Cl, HCO 3=CO_3^(2 -)and SO2 4ions have little effect on BrO_3removal, whereas NO_3can inhibit its removal as a result of competition with BrO_3for e aq.

关键词： γ射线照射水溶液溴酸盐吸收剂量二氧化碳高pH值消毒副产物含气饱和度

NN-based Output Tracking for More General Stochastic Nonlinear Systems with Unknown Control Coefficients

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International Journal of Automation and computing 2017年第3期14卷 350-359页

作者： Na Duan hui-fang Min School of Electrical Engineering & Automation Jiangsu Normal UniversityXuzhou 221116 China

This paper considers the output tracking problem for more general classes of stochastic nonlinear systems with unknown control coefficients and driven by noise of unknown covariance. By utilizing the radial basis function neural network approximation method and backstepping technique, we successfully construct a controller to guarantee the solution process to be bounded in *** tracking error signal is 4th-moment semi-globally uniformly ultimately bounded（SGUUB） and can be regulated into a small neighborhood of the origin in probability. A simulation example is given to demonstrate the effectiveness of the control scheme.

关键词： Stochastic nonlinear systems unknown control coefficients output tracking neural networks backstepping

Structure of MgSO_4 in Concentrated Aqueous Solutions by X-Ray Diffraction

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Chemical Research in Chinese Universities 2011年第3期27卷 490-495页

作者： CAO Ling-di fang Yah fang Chun-hui Key Laboratory of Salt Resources and Chemistry Institute of Salt Lakes Chinese Academy of Sciences Xining 810008 P. R. China＂ Graduate School of Chinese Academy of Sciences Beijing 100049 P. R. China

Detailed time-and-space-averaged structure of MgSO4 in the concentrated aqueous solutions was investigated via X-ray diffraction with an X’pert Pro θ-θ diffractometer at 298 K, yielding structural function and radial distribution function（RDF）. The developed KURVLR program was employed for the theoretical investigation in consideration of the ionic hydration and ion association. Multi-peaks Gaussian fitting method was applied to deconvolving the overlapping bands of Differential radial distribution function（DRDF）. The calculation of the geometric model shows that octahedrally six-coordinated Mg（H2O）62＋, with an Mg2＋…OW bond length of 0.201 nm dominates in the solutions. There exists contact ion-pair（CIP） in the more concentrated solution（1：18, H2O/salt molar ratio） with a coordination number of 0.8 and a characteristic Mg…S distance of 0.340 nm. The result indicates the hydrated SO42– ion happens in the solution. The S…OW bond distance was determined to be 0.382 nm with a coordination number of 13. The fraction of CIP increases significantly with the increasing concentration. The symmetry of the hydration structure of sulfate ion is lowered by forming complex with magnesium ion.

关键词： Solution structure X-Ray diffraction Magnesium sulfate Radial distribution function(RDF)

Microstructures of Ti–Ni–Fe wire after severe cold-drawing and annealing

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Rare Metals 2013年第6期32卷 550-554页

作者： hui-fang Geng Fu-Shun Liu School of Material Science and Engineering Beijing University of Aeronautics and Astronatics

The microstructures and mechanical properties of Ti–47 at%Ni–3 at%Fe shape memory alloy wire under the condition of severe cold-drawing at room temperature and different postdeformation annealing processes were intensively investigated using transmission electron microscope(TEM),X-ray diffraction(XRD),Vickers microhardness tester and electron tensile *** is indicated that the structure of the alloy evolves into a predominant amorphous structure with a trace of nanocrystalline B2 phase after the cold-drawing of 76%areal *** annealing process exerted significant influence on the microstructure and mechanical *** occurs when the cold-drawn wire was annealed at 300℃ for 30 *** ultimate tensile strength and ductility as well as the superelasticity of the wire are improved significantly by cold-drawing plus postdeformation annealing.

关键词： Ti–Ni–Fe wire Severe plastic deformation Cold-drawing Annealing Amorphous structure

Reputation-based linear cooperation for spectrum sensing in cognitive radio networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第12期10卷 1688-1695页

作者： hui-fang CHEN Xu JIN Lei XIE Department of lnformation Science and Electronic Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Key Laboratory of Information Network Technology Hangzhou 310027 China

We propose a reputation-based cooperative spectrum sensing scheme in cognitive radio (CR) networks to solve the uncertainty resulting from the multipath fading and shadowing effect. In the proposed scheme, each cooperative CR user has a reputation degree that is initialized and adjusted by the central controller, and used to weight the sensing result from the corresponding CR user in the linear fusion process at the central controller. A simple method for adjusting the reputation degree of CR users is also presented. We analyzed and evaluated the detection performance of the reputation-based cooperative spectrum sensing scheme. Simulation results showed that our proposed scheme alleviates the problem of corrupted detection resulting from destructive channel conditions between the primary transmitter and the CR user. The performance of our proposed scheme was improved compared to the average-based linear cooperation scheme, and was similar to that of the optimal linear cooperation scheme with feasible computational complexity. Moreover, our proposed scheme does not require knowledge of channel statistics.

关键词： Cognitive radio networks Cooperative Reputation Spectrum sensing

Concise Cascade Methods for Transgenic Rice Seed Discrimination using Spectral Phenotyping

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Plant Phenomics 2023年第3期5卷 564-580页

作者： Jinnuo Zhang Xuping Feng Jian Jin hui fang Department of Agricultural and Biological Engineering Purdue UniversityWest LafayetteIN 47907USA College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhouChina Huzhou Institute of Zhejiang University HuzhouChina

Currently,the presence of genetically modified(GM)organisms in agro-food markets is strictly regulated by enacted legislation *** is essential to ensure the traceability of these transgenic products for food safety,consumer choice,environmental monitoring,market integrity,and scientific ***,detecting the existence of GM organisms involves a combination of complex,time-consuming,and labor-intensive techniques requiring high-level professional *** this paper,a concise and rapid pipeline method to identify transgenic rice seeds was proposed on the basis of spectral imaging technologies and the deep learning *** composition of metabolome across 3 rice seed lines containing the cry1Ab/cry1Ac gene was compared and studied,substantiating the intrinsic variability induced by these GM *** showed that near-infrared and terahertz spectra from different genotypes could reveal the regularity of GM metabolic *** established cascade deep learning model divided GM discrimination into 2 phases including variety classification and GM status *** could be found that terahertz absorption spectra contained more valuable features and achieved the highest accuracy of 97.04%for variety classification and 99.71%for GM status ***,a modified guided backpropagation algorithm was proposed to select the task-specific characteristic wavelengths for further reducing the redundancy of the original *** experimental validation of the cascade discriminant method in conjunction with spectroscopy confirmed its viability,simplicity,and effectiveness as a valuable tool for the detection of GM rice *** approach also demonstrated its great potential in distilling crucial features for expedited transgenic risk assessment.

关键词： fir simplicity consuming

Synthesis and in vitro-Anti-hepatitis B Virus Activities of Several Ethyl 5-Hydroxy-1H-indole-3-carboxylates

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Chemical Research in Chinese Universities 2006年第5期22卷 577-583页

作者： ZHAO Chun-shen ZHAO Yan-fang CHAI hui-fang GONG Ping Liaoning Province Key Laboratory of Innovative Medicine Research and Design Shenyang Pharmaceutical University Shenyang 110016 P. R. China

A series of ethyl 5-hydroxyindole-3-earboxylates 6a-10r was designed and synthesized. The structures of all the compounds were confirmed by IR, ^1H NMR, and MS and their anti-hepatitis B virus （HBV） activities were evaluated in 2.2.15 cells. Among them, compound 7g { ethyl 5-hydroxy-2- [ （ 3-methoxyphenylsulfinyl ） methyl ] -1-methyl-4- [ （4-methylpiperazin-1-yl） methyl ]-1H-indole-3-carboxylate} displays a significant anti-HBV activity, which is more potent than the positive control lamivudine.

关键词： Ethyl 5-hydroxy-1H-indole-3-carboxylates Synthesis Anti-hepatitis B virus activity