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Journal of Systems Engineering and Electronics 2018年第3期29卷 580-586页

作者： yanG Yueneng yan ye College of Aerospace Science and Engineering National University of Defense Technology

A neural-network-based adaptive gain scheduling backstepping sliding mode control（NNAGS-BSMC） approach for a class of uncertain strict-feedback nonlinear system is ***, the control problem of uncertain strict-feedback nonlinear systems is formulated. Second, the detailed design of NNAGSBSMC is described. The sliding mode control（SMC） law is designed to track a referenced output via backstepping *** decrease chattering result from SMC, a radial basis function neural network（RBFNN） is employed to construct the NNAGSBSMC to facilitate adaptive gain scheduling, in which the gains are scheduled adaptively via neural network（NN）, with sliding surface and its differential as NN inputs and the gains as NN outputs. Finally, the verification example is given to show the effectiveness and robustness of the proposed approach. Contrasting simulation results indicate that the NNAGS-BSMC decreases the chattering effectively and has better control performance against the BSMC.

关键词： backstepping control sliding mode control(SMC) neural network(NN) strict-feedback system chattering decrease

Decoupled nonsingular terminal sliding mode control for affine nonlinear systems

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Journal of Systems Engineering and Electronics 2016年第1期27卷 192-200页

作者： Yueneng yang ye yan College of Aerospace Science and Engineering National University of Defense Technology

A decoupled nonsingular terminal sliding mode control（DNTSMC） approach is proposed to address the tracking control problem of affine nonlinear systems.A nonsingular terminal sliding mode control（NTSMC） method is presented,in which the nonsingular terminal sliding surface is defined as a special nonsingular terminal function and the convergence time of the system states can be *** affine nonlinear system is firstly decoupled into linear subsystems via feedback ***,a nonsingular terminal sliding surface is defined and the NTSMC method is applied to each subsystem separately to ensure the finite time convergence of the closed-loop *** verification example is given to demonstrate the effectiveness and robustness of the proposed *** proposed approach exhibits a considerable advantage in terms of faster tracking error convergence and less chattering compared with the conventional sliding mode control（CSMC）.

关键词： nonlinear control feedback linearization terminal sliding mode control nonsingular affine nonlinear system.

ON THE STABILITY OF PERIODIC SOLUTIONS OF PIECEWISE SMOOTH PERIODIC DIFFERENTIAL EQUATIONS

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Acta Mathematica Scientia 2024年第4期44卷 1524-1535页

作者： Maoan HAN yan ye School of Mathematical Sciences Zhejiang Normal UniversityJinhua 321000China

In this paper,we address the stability of periodic solutions of piecewise smooth periodic differential *** studying the Poincarémap,we give a sufficient condition to judge the stability of a periodic *** also present... 详细信息

关键词： periodic solution Poincarémap periodic equation stability

Design and Realization of Mineral Feeding SCADA System

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Journal of China University of Mining and Technology 2006年第1期16卷 68-70,76页

作者： ye yan-fei College of Electrical Engineering Hohai University Nanjing Jiangsu 210098 China

The grinding process in concentration plants of the metallurgical industry is of great importantce.. A mineral feed- ing SCADA system in the grinding process was designed with the idea of integrating management and control functions. A detailed design and realization method of control and supervisory control levels in the system was introduced. At the control level, with an algorithm of a separate integrated PID, four mineral feeding machines are run in turn. The supervisory control level can generate process flow graphs, statistical report forms, historical trends and at the same time, it has the functions of alarm, system administration, user login, etc. After the mineral SCADA system has been started, the mineral feeding is very stable, the workstation completely supervises and controls the entire process of mineral feeding, and at the same time histori- cal data is shown and questions can be answered conveniently. The system runs well in the MeiShan Concentration Plant of the Shanghai Bao Shan Steel Group.

关键词： mineral feeding SCADA system control level management

Pseudospectral method for optimal propellantless rendezvous using geomagnetic Lorentz force

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Applied Mathematics and Mechanics(English Edition) 2015年第5期36卷 609-618页

作者： Xu HUANG ye yan yang ZHOU Hua ZHANG College of Aerospace Science and Engineering National University of Defense Technology Department of Communication Beijing Aerospace Control Center

A charged spacecraft is subject to the Lorentz force when it orbits a central body with a magnetic field. The induced Lorentz force provides a new mean of propellantless electromagnetic propulsion for orbital control. Modeling the Earth magnetic field as a tilted dipole that co-rotates with the Earth, this paper develops a nonlinear dynamical model that describes the relative motion of the Lorentz spacecraft about an arbitrary reference orbit. Based on the proposed dynamical model, feasibility of Lorentz-propelled rendezvous with no restrictions on the initial states is investigated. The rendezvous problem is then formulated as an optimal control problem, and solved with the Gauss pseudospectral method（GPM）. Numerical simulations substantiate the validity of proposed model and method, and results show that the propellantless rendezvous is achieved at both fixed and free final time.

关键词： Lorentz dynamical dipole spacecraft propulsion validity orbital integer formulated constraints

An Enhanced LMI Approach for Mixed H2/H∞ Flight Tracking Control

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Chinese Journal of Aeronautics 2011年第3期24卷 324-328页

作者： ZHANG Qingjiang ye Sijun LI yan WANG Xinmin School of Automation Northwestern Polytechnical University Xi 'an 710072 China

The coupling between the Lyapunov variables and system matrices makes the problem of mixed H2/H∞ flight tracking controller design non-convex. With the aid of enhanced linear matrix inequality （LMI） approach, the non-convex optimization problem is transformed into convex LMI representations. The proposed coupling is eliminated by introducing slack variables. Moreover, a necessary and sufficient condition is derived for the mixed H2/H∞ flight tracking controller which not only stabilizes the controlled system but also satisfies the mixed H2/H∞ performance index in normal case and fault cases. The new enhanced LMI representations provide additional degrees of freedom to solve the non-convex optimization problem, and reduce the conservativeness of the controller design. Simulation results of the aero-data model in a research environment （ADMIRE） model show the advantages of the enhanced LMI approach.

关键词： mixed H2/H∞ control flight control tracking reliable control linear matrix inequality

A Novel 3D Supramolecular Network Constructed from [Cu(4,4'-bipyridine)(O_2CMe)_2]_2 Molecular Ladders by Hydrogen Bonding

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1365-1368页

作者： yanG E WANG Xiao-Qin QIN ye-yan College of Chemistry ＆ Materials Science Fujian Normal University Fuzhou 350007 China Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou 350002 China

The title complex, {[Cu2（4,4＇-bipyridine）2（μ-O2CMe）2（O2CMe）2],H2O}n 1, was synthesized and structurally characterized by X-ray crystallography. It crystallizes in monoclinic, space group C2/c with a = 13.4474（5）, b = 11.7566（2）, c = 19.5380（6）A, β = 92.930（2）°, V = 3084.84（16） A^3, Z = 4, Cu2C28N409H30, Mr = 693.64, Dc = 1.494 g/cm^3, F（000） = 1424 and μ（MoKα） = 1.436 mm^-1. With the use of 2062 observed reflections （I 〉 2σ（I））, the structure was refined to R = 0.0769 and wR = 0.2154. In complex 1, the dimeric copper acetate units are linked through 4,4’-bipyridine to yield ID molecular ladders. These ladders are connected via O-H…O hydrogen bonds to generate 2D layers, which are further linked through C-H…O hydrogen bonds to give a 3D supramolecular network.

关键词： molecular ladder dimeric copper acetate 3D supramolecular network

A new sesterterpenoid from the fruits of Phellodendron chinense *** Schneid

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Chinese Chemical Letters 2008年第8期19卷 937-939页

作者： Chen yan ye Wang Xiao Jiang Hao The Key Laboratory of Chemistry for Natural Products of Guizhou Province and Chinese Academy of Sciences Guiyang 550002 China

A new sesterterpenoid phellogine was isolated from the fruits of Phellodendron chinense var. glabriusculum Schneid. Its structure was elucidated on the basis of spectral analysis.

关键词： Phellodendron chinense var. glabriusculum Schneid. Phellogine

Marketing Model Analysis of Fashion Communication Based on the Visual Analysis of Neutrosophic Systems

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Intelligent Automation & Soft Computing 2023年第8期37卷 1257-1274页

作者： Fangyu ye Xiaoshu Xu Yunfeng Zhang yan ye Jingyu Dai School of Design East China Normal UniversityShanghai200063China School of Foreign Studies Wenzhou UniversityWenzhouZhejiang325000China Centre for Portuguese Studies Macao Polytechnic University999078Macao Graduate School of Education Stamford International University of Thailand999003Thailand College of Art Design and Media Sanda UniversityShanghai201209China

In order to Improvement the Neutrosophic sets as effective tools to deal with uncertain and inconsistent *** research takes method-ology of combined single-valued neutrosophic rough set and multi-scale deci-sion *** paper proposes the optimal scale selection and reduction algorithms based on multi-scale single-valued neutrosophic dominance rough set *** requirements were analyzed using KJ method to construct a hierarchical *** to the statistics of representative studies from China and the West,we found that,on the one hand,classical theory has been expanded and supplemented in fashion culture communication and *** topics are more micro-diverse,and the research methods are inspired by other disciplines;on the other hand,Chinese practice and Chinese cultural perspective need to fill the *** fashion content in the new fashion,however,needs to broaden its boundaries,and in addition to integrating with cultural theory and sociology,it needs to be integrated with fashion products,including product design,visual communication,image design and so *** communication needs to be taken into account as an important connotation,with visual communication and the communication of images as important research *** the whole,this research abroad inspires the development of domestic fashion culture communication and marketing research.

关键词： Interval valued neutrosophic AHP fashion culture fashion marketing model construction

New preparation of Mg-Li-Al alloys by electrolysis in molten salt

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Acta Metallurgica Sinica(English Letters) 2010年第2期23卷 129-136页

作者： Wei HAN Qiong CHEN Ke ye Yongde yan Milin ZHANG Key Laboratory of Superlight Materials and Surface Technology Ministry of Education College of MaterialScience and chemical Engineering Harbin Engineering University Harbin 150001 China

This work presents a study on electrochemical formation of Mg-Li-Al alloys on an inert electrode （Mo electrode） in a molten KCl-LiCl-AlC13-MgCI2-KF system. It aims at preparation Mg-Li-Al metal alloy directly under an optimal electrolytic parameters. Main factors which affect current efficiency are investigated. We have discussed the co-electrodeposition conditions and the effect of technical parameters on these experiments, and gained a good electrolytic process. The result of calculation shows that co-electrodeposition Mg, Li and A1 occurs at the cathode current density higher than 9 A/cm^2 and electrolytic voltage between 6 to 9 V. And at the optimal parameters, 12-13 A/cm^2, 620-640 ℃, the highest current efficiency reaches as high as 86%. Lithium combined with magnesium forms Li0.92Mg4.0s and LiaMg7, and aluminum mainly exists in a form of Mg0.58Al0.42, distributing in the alpha phases and beta phases.

关键词： Mg-Li-Al Molten salts Co-electrodeposition Electrolysis