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基于ESO的船舶航向鲁棒自适应控制

控制与决策 2022年第8期37卷 2157-2162页

作者：刘志全褚振忠上海海事大学航运技术与控制工程交通运输行业重点实验室上海201306 上海海事大学物流工程学院上海201306

针对具有内部未建模动态和外部不确定扰动的水面船舶设计一种鲁棒自适应航向控制器,并同时解决转向过程中的漂角补偿问题.基于二阶非线性Nomoto模型和一阶漂角模型,建立非积分链结构的漂角-航向非线性状态空间模型,将航向控制系统未建... 详细信息

针对具有内部未建模动态和外部不确定扰动的水面船舶设计一种鲁棒自适应航向控制器,并同时解决转向过程中的漂角补偿问题.基于二阶非线性Nomoto模型和一阶漂角模型,建立非积分链结构的漂角-航向非线性状态空间模型,将航向控制系统未建模动态与外部不确定扰动合并为复合扰动,应用扩张状态观测器估计模型中的未测量状态和系统复合扰动.基于Lyapunov稳定性理论和自适应反步法设计航向状态反馈控制规律,为避免反步法控制过程中的微分爆炸问题,采用动态面控制技术获取虚拟控制信号的近似导数.所提出的扩张状态观测器和航向控制算法能够保证闭环系统内所有误差信号一致最终有界,提高航向保持和转向过程中的航向跟踪精度.仿真结果验证了所提出的航向控制规律的有效性.

关键词：扩张状态观测器航向控制动态面反步法自适应漂角

Design of Adaptive Variable Structure Tracking Controllers for A Class of Systems with Nonholonomic Constraints

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Design of Adaptive Variable Structure Tracking Controllers f...

第37届中国控制会议

作者： Chih-Chiang Cheng Cheng-Yun chu Electrical Engineering Sun Yat-Sen University

Based on the Lyapunov stability theorem, a design methodology of adaptive variable structure tracking controller is proposed in this paper for a class of perturbed nonlinear systems with nonholonomic constraints to solve the trajectory tracking control problems. In the first stage, the nonhomogeneous dynamics constraints of the plant are transformed into a general multichained form, and a desired velocity input function is designed by utilizing backstepping control technique. In the second stage,the proposed controller is designed by using variable structure control（VSC） methodology with adaptive mechanism embedded,so that the tracking errors of both transformed states and the original states are able to achieve asymptotic stability. In addition,the velocity trajectories of the controlled systems can track the desired velocity input function designed in the first stage in a finite time. The upper bounds of perturbations are not required to be known in advance due to employed adaptive ***, a practical example is given for demonstrating the feasibility of the proposed control scheme.

关键词： Variable structure control backstepping control Nonholonomic constraint

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多孔介质中流体输运的孔尺度SPH模拟

工程热物理学报 2009年第3期30卷 437-440页

作者：初阳卢文强中国科学院研究生院物理科学学院北京100049

本文采用光滑粒子流体动力学(SPH)方法对流体流过多孔介质的过程进行数值模拟,方法与程序用经典的Poiseuille流与多孔介质流动的Kozeny解进行了验证。SPH进一步用于数值模拟跨膜流动,获得了跨膜流动中速度场随时间的演化过程。多孔膜孔... 详细信息

本文采用光滑粒子流体动力学(SPH)方法对流体流过多孔介质的过程进行数值模拟,方法与程序用经典的Poiseuille流与多孔介质流动的Kozeny解进行了验证。SPH进一步用于数值模拟跨膜流动,获得了跨膜流动中速度场随时间的演化过程。多孔膜孔径在1μm到200μm范围内,流体跨膜渗透速度的SPH结果与K-K方程的计算值吻合较好。文中还讨论了粒子数目与计算精度的关系。本文的计算结果表明SPH方法具有模拟多孔介质微流动的能力。

关键词：光滑粒子动力学(SPH) 多孔介质渗透速度 K—K方程

A Modified Adaptive Fuzzy Control Based on Backstepping Design for Three-Phase Active Power Filter

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A Modified Adaptive Fuzzy Control Based on Backstepping Desi...

第37届中国控制会议

作者： Shixi Hou Juntao Fei Yundi chu Jiangsu Key Laboratory of Power Transmission ＆ Distribution Equipment Technology

In this paper, a modified adaptive fuzzy control based on backstepping design（MAFCBD） is proposed for active power filter（APF） to attenuate the effect of unknown external disturbances and modeling uncertainties. Firstly, a backstepping control strategy for active power filter is proposed, which simplifies the design of the controller, and is easy to implement in the active power filter. Then fuzzy logic system is used to approximate unknown nonlinear function to suppress the influence of parameter uncertainty, and the proposed controller with compensation control based on the fuzzy approximation error estimation can overcome the influence of the fuzzy approximation error on the stability of the system, improving the effect of compensation current tracking and strengthening the ability of harmonic suppression. Simulation studies in the MATLAB/Sim Power Systems Toolbox demonstrate that the proposed control methods offer a good behavior in both steady state and transient operation during balanced and unbalanced load compared to traditional backstepping control.

关键词： Active power filter adaptive fuzzy control backstepping method approximation error

Two Indirect Adaptive Fuzzy Sliding Mode Control of Three-Phase Active Power Filter Under Different Conditions

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Two Indirect Adaptive Fuzzy Sliding Mode Control of Three-Ph...

第30届中国控制与决策会议

作者： Shixi Hou Juntao Fei Yundi chu College of IOT Engineering Hohai University

In this paper,two indirect adaptive fuzzy sliding mode control methods are proposed for the current tracking control of active power filter in view of the influence of the parameter perturbation and the unknown *** the first scheme,a fuzzy system is used to approximate the unknown dynamics in order to eliminate the dependence on the prior knowledge,and another fuzzy system is used to replace the switching control term to reduce the chattering *** the second scheme,based on feedback linearization idea,sliding mode controller for active power filter is designed *** the fuzzy systems are used to approximate unknown nonlinear functions and the lumped uncertainty which weaken the dependence on mathematical model of the system,effectively improving the system *** the two schemes,the compensation control term is designed based on the fuzzy approximation error estimation,which ensures the tracking performance of the closed loop *** studies in the MATLAB/SimPower Systems Toolbox demonstrate that the proposed control methods offer a good behavior in both steady state and transient operation during balanced and unbalanced load.

关键词： Active power filter adaptive fuzzy control sliding mode control feedback linearization

Yizhi Xingnao prescription improves the cognitive function of patients after a transient ischemic attack

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Neural Regeneration Research 2012年第6期7卷 434-439页

作者： Donglin Jiang Xing chu Lingling Hu Shengyang Jiang Feng Hu Junming Sun Chengwan Li The Third Affiliated Hospital of Nantong University Wuxi 214000 Jiangsu Province China

Patients with mild cognitive impairment after a transient ischemic attack were included in this study. They were treated with Yizhi Xingnao prescription, ergoloid mesylates or aspirin for 60 days. Evaluation using the Montreal Cognitive Assessment Scale showed that cognitive function was significantly improved in all patients, especially after the combined treatment of Yizhi Xingnao and aspirin. The scores from the Montreal Cognitive Assessment Scale were improved overall and the effective treatment rate was as high as 79%, which was higher than patients treated with a combination of ergoloid mesylates and aspirin, or aspirin alone. Our experimental findings indicate that YizhiXingnao prescription can improve mild cognitive impairment after a transient ischemic attack, and that it is more effective than ergoloid mesylates.

关键词： Yizhi Xingnao prescription transient ischemic attack mild cognitive impairment Montreal Cognitive Assessment Scale ergoloid mesylates aspirin

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再生砂超高性能混凝土力学性能研究

建筑材料学报 2020年第4期23卷 810-815页

作者：葛晓丽褚洪岩江苏省建筑工程质量检测中心有限公司江苏南京210028 南京林业大学土木工程学院江苏南京210037

将废弃混凝土制成再生砂后,以不同掺量替代天然河砂,按标准试验方法制备了再生砂超高性能混凝土(UHPC),通过测试其各项力学性能,探究用再生砂制备UHPC的可行性.结果表明:再生砂在UHPC中的优选替代率为40%~60%,当再生砂替代率为60%时,再... 详细信息

将废弃混凝土制成再生砂后,以不同掺量替代天然河砂,按标准试验方法制备了再生砂超高性能混凝土(UHPC),通过测试其各项力学性能,探究用再生砂制备UHPC的可行性.结果表明:再生砂在UHPC中的优选替代率为40%~60%,当再生砂替代率为60%时,再生砂UHPC具有较好的力学性能,其抗压强度、抗折强度、劈裂抗拉强度和弹性模量依次为170.26、19.45、12.17MPa和50.65GPa,比再生砂替代率为0%的对照组分别提高了1.88%、12.88%、8.27%和5.65%;随着再生砂替代率的增加,再生砂UHPC中的毛细孔占比呈现出先增大后减小趋势,表明掺入再生砂可以在一定程度上优化UHPC的孔径结构.

关键词：超高性能混凝土再生砂力学性能微观结构孔隙率

Editorial: IET Cyber-systems and Robotics

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IET Cyber-Systems and Robotics 2019年第1期1卷 1-1页

作者： chu, Jian Buckingham, Rob Meng, Max Supcon Grp Hangzhou Peoples R China Zhejiang Univ Hangzhou Peoples R China Zhejiang Univ Inst Adv Proc Control Hangzhou Peoples R China UKAEA Abington PA USA RACE UKs New Ctr Culham Oxon England OC Robot Bristol Avon England Royal Acad Engn London England Inst Engn & Technol London England CUHK Dept Elect Engn Hong Kong Peoples R China IEEE Robot & Automat Soc AdCom Adm Comm Piscataway NJ USA

We are honored to serve as the inaugural Editors-in-Chief of the new journal,IET Cyber-systems and *** 1948,Norbert Wiener published the famous book‘Cybernetics:or Control and Communication in the Animal and the Machine’which defines cybernetics as a cutting-edge discipline of synergic studies between control and communication in both animals and *** the 1950s,cybernetics was more like a philosophical concept rather than an easily available technology of that *** the rapid progress in many areas such as automatic control,artificial intelligence,neuroscience,and communication within the past decades,nowadays the magnificent picture sketched by Wiener in his‘Cybernetics’book is becoming a *** numerous examples,brain-computer interface(BCI)is the most exciting representative of cybernetics,where bi-directional information flow exists between the bio-minds and manmade machines.

关键词： sketch becoming journal

Chemoproteomic profiling of dopamine-quinone modifications

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Chemoproteomic profiling of dopamine-quinone modifications

第十一届全国化学生物学学术会议

作者： Qianwen Wang Ying Chen chu Wang College of Chemistry and Molecular Engineering Peking University

Parkinson’s disease(PD) is a common degenerative disease of the nervous system which is characterized by the degeneration and death of dopaminergic neurons as well as significant reduction of dopamine in the substantia ***,the molecular mechanism of these pathologic changes is still ***,some researches suggested that dopamine and its oxidative products may play an important role in PD through reacting with nucleophilic residues especially Cys,Lys and His,leading to protein-quinone modifications and abnormal disturbance such as mitochondria dysfunction,protein degradation dysfunction and oxidative stress.C-DA labeling,nitroblue tetrazolium(NBT)/glycinate redox-cycling staining and near-IR fluorescence have been used to detect such modification ,but they hardly provide the information of modification ***,we synthesized a probe named DAyne which has the similar structure of DA and developed an ABPP-based chemoproteomic platform to identify DA-quinone(DAQ) modification sites in vitro and in *** found some known DAQ-modified ***,we also found some dopamine-hypersensitive sites in our rdTOP-ABPP *** some of them need to be verified,they may provide new insig hts into PD researches.

关键词： Parkinson’s disease Dopamine quinone modification ABPP