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Noise-Tolerant ZNN-Based Data-Driven Iterative Learning Control for Discrete Nonaffine Nonlinear MIMO Repetitive Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 344-361页

作者： Yunfeng Hu Chong Zhang Bo Wang Jing zhao Xun Gong jinwu Gao Hong Chen State Key Laboratory of Automotive Simulation and Control Jilin UniversityJilin UniversityChangchun 130025China College of Communication Engineering Jilin UniversityJilin UniversityChangchun 130025China Department of Electromechanical Engineering University of MacaoMacao 999078China School of Artificial Intelligence Jilin UniversityChangchun 130012China IEEE College of Electronics and Information Engineering Tongji UniversityShanghai 200092China

Aiming at the tracking problem of a class of discrete nonaffine nonlinear multi-input multi-output(MIMO) repetitive systems subjected to separable and nonseparable disturbances, a novel data-driven iterative learning control(ILC) scheme based on the zeroing neural networks(ZNNs) is proposed. First, the equivalent dynamic linearization data model is obtained by means of dynamic linearization technology, which exists theoretically in the iteration domain. Then, the iterative extended state observer(IESO) is developed to estimate the disturbance and the coupling between systems, and the decoupled dynamic linearization model is obtained for the purpose of controller synthesis. To solve the zero-seeking tracking problem with inherent tolerance of noise,an ILC based on noise-tolerant modified ZNN is proposed. The strict assumptions imposed on the initialization conditions of each iteration in the existing ILC methods can be absolutely removed with our method. In addition, theoretical analysis indicates that the modified ZNN can converge to the exact solution of the zero-seeking tracking problem. Finally, a generalized example and an application-oriented example are presented to verify the effectiveness and superiority of the proposed process.

关键词： Adaptive control control system synthesis data-driven iterative learning control neurocontroller nonlinear discrete time systems

A Facile and Practical Process for the Synthesis of Polysubstituted Furans from Alkynes Using Atmospheric Oxygen as a Terminal Oxidant

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Chinese Journal of Chemistry 2014年第11期32卷 1099-1102页

作者： Jingxiu Xu Xingdong Song jinwu zhao School of Pharmacy Guangdong Medical CollegeDongguanGuangdong 523808China

We present here a facile and practical procedure for the synthesis of tetrasubstituted furans from alkynes catalyzed by palladium acetate together with cupric acetate in acetic acid,using atmospheric oxygen as a termi... 详细信息

关键词： furan alkyne palladium copper oxygen

STUDY ON MACRO AND MICRO MODELING ON SOLIDIFICATION PROCESS OF SHAPED CASTING

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Chinese Journal of Mechanical Engineering 2002年第3期15卷 252-256页

作者： Liu Baicheng Kang jinwu zhao Haidong Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China Department of Mechanical Engineering Tsinghua University 北京 100084

Facing the market economy and global challenge the development ofmanufacturing industry especially casting industry is critical to the national economy. To reformthe traditional casting industry by using computer technology is one of the hottest researchfrontiers studied by many researchers and engineers. Computer simulation of solidification processof shaped casting can assure the quality of casting, optimize the casting technology, shorten thelead time and therefore decrease the developing and manufacturing cost. Recently, numericalsimulation of mold-filling and solidification processes of shaped casting and prediction ofmicrostructure and property as well are extensively studied and put into application in many castingplants with many successful simulation cases.

关键词： Shaped casting Solidification Mold filling Stress analysis Modelingand simulation

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小波梯度域重建融合法应用于龋齿太赫兹成像

红外技术 2023年第8期45卷 890-896页

作者：柳启航何明霞赵晋武李岩天津大学测试计量技术及仪器国家重点实验室天津300072 天津大学精密仪器与光电子工程学院天津300072

龋病是发病率最高的口腔疾病,也是全世界最流行的疾病之一。太赫兹光谱成像技术因具有宽频带光谱分析能力强、空间分辨率高、电离辐射低等优势,有望成为龋病诊断的新技术手段。本文以含牙本质龋的牙齿切片为研究对象,进行反射式太赫兹... 详细信息

龋病是发病率最高的口腔疾病,也是全世界最流行的疾病之一。太赫兹光谱成像技术因具有宽频带光谱分析能力强、空间分辨率高、电离辐射低等优势,有望成为龋病诊断的新技术手段。本文以含牙本质龋的牙齿切片为研究对象,进行反射式太赫兹光谱扫描,以频域幅值为参数对样品的光谱数据做二维重构成像,获得多幅不同频率下的龋齿太赫兹光谱图像。为了解决单一参数所得的龋齿太赫兹图像动态范围小、对比度低,边缘和细节位置模糊不清的问题,采用小波梯度域重建的融合方法,将多幅图像中梯度幅值较大的部分集中于一幅图像上,得到了一幅细节特征更加清晰完整的新图像。实验结果表明,融合后的图像相较于融合前的图像在信息熵、平均梯度以及对比度上均有所提高,不同组织之间的区分效果更加显著。

关键词：龋齿检测太赫兹光谱成像小波梯度域重建图像融合

Influence of exchange bias on spin torque ferromagnetic resonance for quantification of spin–orbit torque efficiency

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Chinese Physics B 2024年第5期33卷 688-694页

作者：赵乾张腾飞何斌李子木张森富于国强王建波刘青芳魏晋武 Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Special Functional Materials and Structural Design Ministry of EducationLanzhou UniversityLanzhou 730000China

Antiferromagnet(AFM)/ferromagnet(FM)heterostructure is a popular system for studying the spin–orbit torque(SOT)of ***,the interfacial exchange bias field induces that the magnetization in FM layer is noncollinear to the external magnetic field,namely the magnetic moment drag effect,which further influences the characteristic of SOT *** this work,we study the SOT efficiencies of IrMn/NiFe bilayers with strong interfacial exchange bias by using spin-torque ferromagnetic resonance(ST-FMR)method.A full analysis on the AFM/FM systems with exchange bias is performed,and the angular dependence of magnetization on external magnetic field is determined through the minimum rule of free *** ST-FMR results can be well fitted by this *** obtained the relative accurate SOT efficiencyξ_(DL)=0.058 for the IrMn *** work provides a useful method to analyze the angular dependence of ST-FMR results and facilitates the accurate measurement of SOT efficiency for the AFM/FM heterostructures with strong exchange bias.

关键词： antiferromagnets spin-orbit torque exchange bias spin torque ferromagnetic resonance

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飞行器旋转翼折展过程动稳定性研究进展

北京航空航天大学学报 2024年第4期50卷 1053-1064页

作者：甘文彪左振杰向锦武赵忠良蔡军马上北京航空航天大学无人系统研究院北京100191 北京航空航天大学航空科学与工程学院北京100191 中国空气动力研究与发展中心高速空气动力研究所绵阳621000 湖南云箭集团有限公司长沙410100

旋转翼是一种可绕固定轴旋转变体的机翼,广泛应用于新型无人机、巡飞弹、航空炸弹等飞行器,其折展过程中的动稳定特性是决定旋转翼飞行器设计成败的关键基础问题。基于此,梳理了近年来飞行器旋转翼折展过程动稳定机理的研究进展。介绍... 详细信息

旋转翼是一种可绕固定轴旋转变体的机翼,广泛应用于新型无人机、巡飞弹、航空炸弹等飞行器,其折展过程中的动稳定特性是决定旋转翼飞行器设计成败的关键基础问题。基于此,梳理了近年来飞行器旋转翼折展过程动稳定机理的研究进展。介绍了旋转翼发展历程及其面临的折展动稳定关键问题;从非定常气动数值模拟、非定常动态特性数值模拟、CFD/RBD一体化耦合数值模拟3个层次阐述了折展过程动稳定数值模拟进展;介绍了旋转翼折展扰动下的非线性动力学建模及动稳定性分析的现状;分析了旋转翼折展动稳定性机理的风洞试验验证情况;总结了旋转翼折展过程动稳定研究面临的科学问题,并提出了可行的研究方向。

关键词：非定常流旋转翼气动运动耦合动力学机理动态分析

Adaptive Regulation for Hammerstein and Wiener Systems with Event-Triggered Observations

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Journal of Systems Science & Complexity 2023年第5期36卷 1878-1904页

作者： REN Xiaotao zhao Wenxiao GAO jinwu Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China Department of Control Science and Engineering Jilin UniversityChangchun 130025China

The paper considers the adaptive regulation for the Hammerstein and Wiener systems with event-triggered *** authors adopt a direct approach,i.e.,without identifying the unknown parameters and functions within the systems,adaptive regulators are directly designed based on the event-triggered observations on the regulation *** adaptive regulators belong to the stochastic approximation algorithms and under moderate assumptions,the authors prove that the adaptive regulators are optimal for both the Hammerstein and Wiener systems in the sense that the squared regulation errors are asymptotically *** authors also testify the theoretical results through simulation studies.

关键词： Adaptive regulation event-triggered observation Hammerstein system stochastic approximation algorithm Wiener system

乡村治理数字化转型:缘由、特点、困境与路径

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河北青年管理干部学院学报 2024年第2期36卷 72-80页

作者：唐金武赵祝涛曲阜师范大学马克思主义学院山东济宁272000 北京交通大学马克思主义学院北京100044

随着互联网信息技术的不断完善,乡村治理现代化的持续推进以及城乡融合发展的现实需求,数字化信息技术开始融入乡村社会,助力乡村发展,数字化乡村治理应运而生。通过对数字化乡村治理的特点与困境的考量,得出乡村治理数字化转型在当下... 详细信息

随着互联网信息技术的不断完善,乡村治理现代化的持续推进以及城乡融合发展的现实需求,数字化信息技术开始融入乡村社会,助力乡村发展,数字化乡村治理应运而生。通过对数字化乡村治理的特点与困境的考量,得出乡村治理数字化转型在当下社会发展的优势所在与不足之处。因此,乡村治理数字化转型需培养、引进数字技术人才,助力乡村数字转型;需加快乡村数字基础设施建设,缩小城乡数字鸿沟;需以搭建乡村治理数字平台,推进乡村治理现代化。

关键词：乡村治理数字化特点困境路径

3D打印个性化颈椎矫形支具可缓解和治疗早期颈椎病

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中国组织工程研究 2024年第29期28卷 4639-4644页

作者：杨云霄赵宇王明海杨泽政王金武复旦大学附属上海市第五人民医院骨科上海市200240 潍坊医学院康复医学院山东省潍坊市261053 上海交通大学转化医学研究院上海市201100 上海交通大学医学院附属第九人民医院骨科上海市200011

背景:短时间的颈托佩戴结合肩颈肌肉锻炼可以显著改善早期颈椎病的症状,但是在停止佩戴颈托后患者症状容易再发,原因可能是颈托缺少颈椎曲度矫正功能。目的:分析3D打印个性化颈椎矫形支具调整颈椎曲度治疗早期颈椎病的疗效。方法:选择2... 详细信息

背景:短时间的颈托佩戴结合肩颈肌肉锻炼可以显著改善早期颈椎病的症状,但是在停止佩戴颈托后患者症状容易再发,原因可能是颈托缺少颈椎曲度矫正功能。目的:分析3D打印个性化颈椎矫形支具调整颈椎曲度治疗早期颈椎病的疗效。方法:选择2021年1月至2023年1月复旦大学附属上海市第五人民医院收治的早期颈椎病患者30例,男11例,女19例,平均年龄(31.7±6.6)岁,所有患者定制和佩戴3D打印个性化颈椎矫形支具,每天佩戴3 h,持续治疗12周。记录治疗前及治疗4,8周后30例患者的颈椎曲度Borden值、肩颈部肌肉痛阈、颈椎功能障碍指数、目测类比评分。结果与结论:①与治疗前相比,30例患者治疗4周后的颈椎曲度Borden值、右斜方肌压痛阈值与颈椎功能障碍指数无明显变化(P>0.05),目测类比评分、左斜方肌压痛阈值、左及右C_(5)C_(6)压痛阈值明显改善(P<0.05);②与治疗前相比,30例患者治疗12周后的颈椎曲度Borden值、左及右斜方肌压痛阈值、目测类比评分、左及右C_(5)C_(6)压痛阈值与颈椎功能障碍指数均明显改善(P<0.05);③与治疗4周后相比,30例患者治疗12周后的颈椎曲度Borden值、右斜方肌压痛阈值、目测类比评分、左及右C_(5)C_(6)压痛阈值与颈椎功能障碍指数均明显改善(P<0.05);④结果表明,短期内佩戴3D打印个性化颈椎矫形支具可以改善早期颈椎病患者的疼痛情况,长期佩戴可一定程度地恢复颈椎曲度。

关键词：颈椎病颈托 3D打印支具压痛阈值颈椎功能障碍指数目测类比评分法

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