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IEEE/CAA Journal of Automatica Sinica 2014年第4期1卷 412-422页

作者： jing na Guido Herrmann the Faculty of Mechanical and Electrical Engineering Kunming University of Science and Technology the Department of Mechanical Engineering University of Bristol

This paper proposes an online adaptive approximate solution for the infinite-horizon optimal tracking control problem of continuous-time nonlinear systems with unknown *** requirement of the complete knowledge of system dynamics is avoided by employing an adaptive identifier in conjunction with a novel adaptive law, such that the estimated identifier weights converge to a small neighborhood of their ideal *** adaptive steady-state controller is developed to maintain the desired tracking performance at the steady-state, and an adaptive optimal controller is designed to stabilize the tracking error dynamics in an optimal manner. For this purpose, a critic neural network(NN) is utilized to approximate the optimal value function of the Hamilton-Jacobi-Bellman(HJB) equation,which is used in the construction of the optimal controller. The learning of two NNs, i.e., the identifier NN and the critic NN, is continuous and simultaneous by means of a novel adaptive law design methodology based on the parameter estimation *** of the whole system consisting of the identifier NN,the critic NN and the optimal tracking control is guaranteed using Lyapunov theory; convergence to a near-optimal control law is proved. Simulation results exemplify the effectiveness of the proposed method.

关键词： Optimal control Artificial neural networks Convergence Adaptive systems Approximation methods Parameter estimation Steady-state Learning (artificial intelligence) Adaptive control

Fixed-Time Sliding Mode Control With Varying Exponent Coefficient for Modular Reconfigurable Flight Arrays

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 514-528页

作者： Jianquan Yang Chunxi Yang Xiufeng Zhang jing na Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500 Yunnan International Joint Laboratory of Intelligent Control and Aoolication of Advanced Equipment Kunming 650500China IEEE

The modular system can change its physical structure by self-assembly and self-disassembly between modules to dynamically adapt to task and environmental requirements. Recognizing the adaptive capability of modular systems, we introduce a modular reconfigurable flight array(MRFA) to pursue a multifunction aircraft fitting for diverse tasks and requirements,and investigate the attitude control and the control allocation problem by using the modular reconfigurable flight array as a platform. First, considering the variable and irregular topological configuration of the modular array, a center-of-mass-independent flight array dynamics model is proposed to allow control allocation under over-actuated situations. Secondly, in order to meet the stable, fast and accurate attitude tracking performance of the MRFA, a fixed-time convergent sliding mode controller with state-dependent variable exponent coefficients is proposed to ensure fast convergence rate both away from and near the system equilibrium point without encountering the singularity. It is shown that the controller also has fixed-time convergent characteristics even in the presence of external disturbances. Finally,simulation results are provided to demonstrate the effectiveness of the proposed modeling and control strategies.

关键词： Control allocation dynamic model fixed-time stabilization modular reconfigurable flight array(MRFA) sliding mode

Observer-based Adaptive Optimal Control for Unknown Singularly Perturbed Nonlinear Systems With Input Constraints

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IEEE/CAA Journal of Automatica Sinica 2017年第1期4卷 48-57页

作者： Zhijun Fu Wenfang Xie Subhash Rakheja jing na College of Mechanical Engineering Zhejiang University of Technology Department of Mechanical & Industrial Engineering Concordia University Faculty of Mechanical & Electrical Engineering Kunming University of Science & Technology

This paper introduces an observer-based adaptive optimal control method for unknown singularly perturbed nonlinear systems with input constraints. First, a multi-Time scales dynamic neural network MTSDNN observer with a novel updating law derived from a properly designed Lyapunov function is proposed to estimate the system states. Then, an adaptive learning rule driven by the critic NN weight error is presented for the critic NN, which is used to approximate the optimal cost function. Finally, the optimal control action is calculated by online solving the Hamilton-Jacobi-Bellman HJB equation associated with the MTSDNN observer and critic NN. The stability of the overall closed-loop system consisting of the MTSDNN observer, the critic NN and the optimal control action is proved. The proposed observer-based optimal control approach has an essential advantage that the system dynamics are not needed for implementation, and only the measured input U+002F output data is needed. Moreover, the proposed optimal control design takes the input constraints into consideration and thus can overcome the restriction of actuator saturation. Simulation results are presented to confirm the validity of the investigated approach. © 2014 Chinese Association of Automation.

关键词： Closed loop systems Cost functions Lyapunov functions Neural networks Nonlinear systems Optimal control systems Perturbation techniques

An Extension Landau-Lifshitz Model in Studying Soft Ferromagnetic Films

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Acta Mathematicae Applicatae Sinica 2007年第3期23卷 421-432页

作者： jing-na Li Xiao-feng Wang Zheng-an Yao Department of Mathematics Sun Yat-sen University Guangzhou 510275 China

In this paper, we propose a model in studying soft ferromagnetic films, which is readily accessible experimentally. By using penalty approximation and compensated compactness, we prove that the dynamical equation in t... 详细信息

关键词： Landau-Lifshitz equation thin film, penalty approximation, compensated compactness

THE STUDY OF TYJL-ADX INTERLOCKING SYSTEM BASED COMPUTER

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THE STUDY OF TYJL-ADX INTERLOCKING SYSTEM BASED COMPUTER

The Presentation of Xinjiang Terrorist Attacks in China Daily

第25届中国控制与决策会议

作者： na jing Bing Han The Department of Automation Shanghai Jiaotong University

ISBN: (纸本)9781467355339

The computer based interlocking system equipment of station is very important which does matter with the rail operation safety. TYJL-ADX computer based interlocking system has a structure of 2×2 totally which is a safe redundancy. The FCX unit of one’s mainly logic architecture and FFC unit of operation expression have two systems which can be used as master/slave each other. The each system has a structure of software and hardware with 2×2 safe redundancy. This special structure of TYJL-ADX computer based interlocking system has more reliability. As an main control equipment of railway station it play an important role in ensuring traffic safety, increasing working efficiency .

关键词： TYJL-ADX computer interlocking safe redundancy railway station.

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The Presentation of Xinjiang Terrorist Attacks in China Dail...

作者： jing na 西安外国语大学

学位级别：硕士

发生于2013年新疆巴楚4·23暴力袭警事件引发了笔者对于新疆恐怖主义活动的关注。之后，又发生6·26鄯善恐怖袭击案，造成24人遇害;10·28吉普车冲撞天安门金水桥事件，经调查证实是由“东突厥斯坦伊斯兰运动”恐怖组织精心策划的暴力... 详细信息

发生于2013年新疆巴楚4·23暴力袭警事件引发了笔者对于新疆恐怖主义活动的关注。之后，又发生6·26鄯善恐怖袭击案，造成24人遇害;10·28吉普车冲撞天安门金水桥事件，经调查证实是由“东突厥斯坦伊斯兰运动”恐怖组织精心策划的暴力恐怖袭击案件;11·16喀什地区疏附县暴徒袭警以及12·30喀什地区莎车县公安局再度遇袭。此外，发生于2014年3月1日的昆明恐怖事件在全国范围内造成了极大地负面影响，因此也归为分析对象。由此可见，我国仍然受到新疆恐怖主义的现实威胁。因此，本文希望以China Daily—中国国家英文日报，唯一有效进入国际主流社会、国外媒体转载率最高的中国报纸为文本，基于媒介与恐怖主义相关理论知识，以该报的新疆恐怖活动报道为研究单位，采用框架分析和内容分析法进行全方位的系统研究。文章主要从事发地点、袭击类型、事件背景介绍、消息来源选择、对犯罪者和受害者的描述等多角度详细梳理，以期凸显该报纸就新疆恐怖主义事件的报道模式。文章第一章就研究背景、研究问题、理论依据加以说明;第二章着重将“恐怖主义”这一核心术语予以解释，并对新疆恐怖主义的相关研究进行文献梳理，同时阐述了媒介与恐怖主义的关系;第三章介绍了该论文的研究方法，即内容分析法;第四章基于内容分析法，呈现研究结果;第五章总结该论文的主要发现和不足。纵观国内外学者对于新疆恐怖主义活动的研究，主要聚焦于新疆7·5事件的文本分析，而对于此后该地区的恐怖主义活动关注较少。而该研究发起于2013年新疆巴楚4·23事件，并截取了2013年至2014年3月1日昆明恐怖事件止约127篇关于新疆恐怖主义的报道作为分析文本，其中包括7起重大暴力恐怖事件，以及各方的相关评论。通过框架理论和内容分析法，可以清晰地呈现出ChinaDaily就该议题的报道图景，具有很强的现实意义。同时，基于此项分析，能够进一步探究新闻媒介与恐怖主义的关系。

关键词：新疆恐怖主义《中国日报》框架理论内容分析

M@MIL-100（Fe）（M = Au, Pd, Pt） nanocomposites fabricated by a facile photodeposition process： Efficient visible-light photocatalysts for redox reactions in water

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nano Research 2015年第10期8卷 3237-3249页

作者： Ruowen Liang Fenfen jing Lijuan Shen na Qin Ling Wu StateKeyLaboratoryofPhotocatalysisonEnergyandEnvironment FuzhouUniversityFuzhou350002China

Proper design and preparation of high-performance and stable dual functional photocatalytic materials remains a significant objective of research. In this work, highly dispersed noble-metal nanoparticles （Au, Pd, Pt） were immobilized on MIL-100（Fe）（denoted M@MIL-100（Fe）） using a facile room-temperature photodeposition technique. The resulting M@MIL-100（Fe）（M = Au, Pd, and Pt） nanocomposites exhibited enhanced photoactivities toward photocatalytic degradation of methyl orange （MO） and reduction of heavy-metal Cr（VI） ions under visible-light irradiation （A ≥ 420 nm） compared with blank-MIL-100（Fe）. Combining these results with photoelectrochemical analyses revealed that noble-metal deposition can effectively improve the charge-separation efficiency of MIL-100（Fe） under visible-light irradiation. This phenomenon in turn leads to the enhancement of visible-light-driven photoactivity of M@MIL-100（Fe） toward photocatalytic redox reactions. In particular, the Pt@MIL-100（Fe） with an average Pt particle size of 2 nm exhibited remarkably enhanced photoactivities compared with those of M@MIL-100（Fe）（M = Au and Pd）, which can be attributed to the integrative effect of the enhanced light absorption intensity and more efficient separation of the photogenerated charge carrier. In addition, possible photocatalytic reaction mechanisms are also proposed.

关键词： MIL-100(Fe) photodeposition noble metal redox reactions

Analysis of longitude profiled rolling process of Cu/Al cladded sheet and evaluation of outlet warpage

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Journal of Iron and Steel Research International 2022年第6期29卷 973-982页

作者： jing-na Sun Chi Chen Shuo Wang Guan-nan Liu Hua-gui Huang national Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina Xinxiang Aviation Industry(Group)Co. Ltd.Xinxiang 453000HenanChina Harbin Dongan Engine Co. Ltd.Harbin 150060HeilongjiangChina

Longitude profiled cladded sheet is obtained by rolling bimetal cladded sheet with variable gauge rolling *** longitude profiled rolling process of Cu/Al cladded sheets was studied by finite element method and *** rolling force rises with the increase in reduction,and a sudden change appears at the end of the thickness variation *** thickness ratio of copper layer is enlarged after rolling owing to its relatively large deformation resistance and continues to rise with the increase in reduction *** elongation of copper side leads to the warpage of exit metal to copper side,which further hinders the deformation of *** influence of asymmetric rolling parameters indicates that increasing the work roll diameter ratio,speed radio,and friction coefficient on Al side can reduce the warpage when the reduction rate is below a certain value depending on the thickness ratio and other rolling *** of experiments and simulation results showed good agreement and verified the finite element model.

关键词： Longitude profiled rolling Cladded sheet Rolling force Layer thickness ratio Outlet warpage Asymmetric rolling

Analysis and control of a non-smooth population model with impulsive effects

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International Journal of Biomathematics 2018年第5期11卷 267-283页

作者： jing na Liu Tie Zhang Lichun Zhao Bing Liu Department of Mathematics Northeastern University Shenyang 110006 P. R. China School of Mathematics and Information Science Anshan Normal University AnShan 114007 P. R. China

In this paper, a non-smooth population model with impulsive effects is proposed by combining discontinuity and non-smoothness. According to the qualitative theory of differential equations, the global analysis of the model is discussed. Using the theory of impulsive differential equations, the existence conditions of order one periodic solution are obtained. And the impulsive controllers are designed to make the pest populations stay at the refuge level. Some simulations are carried out to prove the results.

关键词： Impulsive differential equation global analysis order one periodic solution impulsive controller non-smooth population model.

Mechanism of trifluoromethylation reactions with well-defined NHC copper trifluoromethyl complexes and iodobenzene:A computational exploration

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Chinese Chemical Letters 2015年第5期26卷 564-566页

作者： Dong-Hai Yu jing-na Shao Rong-Xing He Ming Li School of Chemistry and Chemical Engineering Southwest University

Computational calculation was performed to investigate the mechanism of trifluoromethylation reactions of iodobenzene with well-defined N-heterocyclic carbene （NHC）-supported Cu~ trifiuor- omethyl complexes. Four proposed reaction pathways, namely cr-bond metathesis （BM）, concerted oxidative addition-reductive elimination （OARE）, iodine atom transfer （IAT） and single-electron transfer （SET）, have been computed by density functional theory （DFT）. The result indicated that the concerted OARE mechanism is favored among the four reaction pathways, suggesting the trifluoromethylation may occur via concerted OARE mechanism involving Ar-X oxidative addition to the Cu（1） center as the rate determining step.

关键词： Trifluoromethylation Mechanism Density functional theory N-Heterocyclic carhene Trifluoromethyl copper complex