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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1285-1295页

作者： Pan-Pan Wang Qiang Yu Yong-Jun Hu chang-xin miao School of Electrical and Power Engineering ChinaUniversity of Mining and Technology Xuzhou 221116China

Current research in broken rotor bar （BRB） fault detection in induction motors is primarily focused on a high-frequency resolution analysis of the stator current. Compared with a discrete Fourier transformation, the parametric spectrum estimation technique has a higher frequency accuracy and resolution. However, the existing detection methods based on parametric spectrum estima- tion cannot realize online detection, owing to the large computational cost. To improve the efficiency of BRB fault detection, a new detection method based on the min-norm algorithm and least square estimation is proposed in this paper. First, the stator current is filtered using a band-pass filter and divided into short overlapped data windows. The min-norm algorithm is then applied to determine the fre- quencies of the fundamental and fault characteristic com- ponents with each overlapped data window. Next, based on the frequency values obtained, a model of the fault current signal is constructed. Subsequently, a linear least squares problem solved through singular value decomposition is designed to estimate the amplitudes and phases of the related components. Finally, the proposed method is applied to a simulated current and an actual motor, the results of which indicate that, not only parametric spectrum estimation technique.

关键词： Fault detection Broken rotor bars Min-norm Least squares method Induction motors

IBPSO-Based MUSIC Algorithm for Broken Rotor Bars Fault Detection of Induction Motors

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 48-57页

作者： Pan-Pan Wang Xiao-Xiao Chen Yong Zhang Yong-Jun Hu chang-xin miao School of Electrical and Power Engineering China University of Mining & Technology Xuzhou 221116 China School of Information and Control Engineering China University of Mining & Technology Xuzhou 221116 China

In spectrum analysis of induction motor current, the characteristic components of broken rotor bars（BRB） fault are often submerged by the fundamental component. Although many detection methods have been proposed for this problem, the frequency resolution and accuracy are not high enough so that the reliability of BRB fault detection is a ected. Thus, a new multiple signal classification（MUSIC） algorithm based on particle swarm intelligence search is developed. Since spectrum peak search in MUSIC is a multimodal optimization problem, an improved bare?bones particle swarm optimization algorithm（IBPSO） is proposed first. In the IBPSO, a modified strategy of subpopulation determination is introduced into BPSO for realizing multimodal search. And then, the new MUSIC algorithm, called IBPSO?based MUSIC, is proposed by replacing the fixed?step traversal search with IBPSO. Meanwhile, a simulation signal is used to test the e ectiveness of the proposed algorithm. The simulation results show that its frequency precision reaches 10-5, and the computational cost is only comparable to that of traditional MUSIC with 0.1 search step. Finally, the IBPSO?based MUSIC is applied in BRB fault detection of an induction motor, and the e ectiveness and superiority are proved again. The proposed research provides a modified MUSIC algorithm which has su cient frequency precision to detect BRB fault in induction motors.

关键词： MUSIC Multimodal Bare?bones particle swarm optimization Induction motors Broken rotor bars Fault detection

动力伺服刀架端齿盘分度精度可靠性灵敏度设计

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东北大学学报（自然科学版） 2017年第6期38卷 834-838页

作者：王新刚常苗鑫张恒吕春梅东北大学机械动力学与可靠性研究中心河北秦皇岛066004 东北大学机械工程及自动化学院辽宁沈阳110819

端齿盘加工精度的高低会直接影响到整个刀架的分度精度.在对端齿盘加工误差进行分析的基础上建立了端齿盘的分度误差模型,利用二阶矩和摄动方法求出端齿盘的可靠性指标,并计算出其可靠度.以端齿盘的分度误差模型为基础,将可靠性理论与... 详细信息

端齿盘加工精度的高低会直接影响到整个刀架的分度精度.在对端齿盘加工误差进行分析的基础上建立了端齿盘的分度误差模型,利用二阶矩和摄动方法求出端齿盘的可靠性指标,并计算出其可靠度.以端齿盘的分度误差模型为基础,将可靠性理论与灵敏度分析方法相结合,给出了动力伺服刀架端齿盘分度精度可靠性灵敏度设计的分析方法.通过算例得出了端齿盘各随机参数的可靠性灵敏度变化规律,并分析了各随机参数的变化对端齿盘分度精度可靠性的影响.研究表明,端齿盘各设计参数的改变对其可靠性的敏感程度不一,可通过优化敏感参数来提高齿盘的分度精度可靠性.同时为提高刀架系统的分度精度可靠性提供理论依据.

关键词：分度端齿盘加工误差分度精度可靠性灵敏度

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从真实世界研究数据看胰岛素临床应用

药品评价 2017年第19期14卷 10-13,20页

作者：常鑫淼郭立新北京医院国家老年医学中心北京100730

真实世界研究目前已引起了广大医务工作者的关注,越来越多的被利用于评价临床干预手段的有效性和安全性。随着疾病的进展,多数糖尿病患者最终需要接受胰岛素治疗。对胰岛素真实世界中的研究结果分析发现,在预混胰岛素、基础胰岛素、基础... 详细信息

真实世界研究目前已引起了广大医务工作者的关注,越来越多的被利用于评价临床干预手段的有效性和安全性。随着疾病的进展,多数糖尿病患者最终需要接受胰岛素治疗。对胰岛素真实世界中的研究结果分析发现,在预混胰岛素、基础胰岛素、基础-餐时胰岛素、餐时胰岛素等目前常用胰岛素治疗方案中,预混胰岛素治疗方案疗效肯定、依从性好,且相对安全,可作为起始或转换胰岛素治疗方案的优选方案之一。同时,真实世界的数据也有助于改进包括联合口服药物的选择、治疗剂量的优化、低血糖的预防等预混胰岛素的使用技巧。

关键词：预混胰岛素糖尿病真实世界研究

Comparative proteomic analysis of plasma exosomes reveals the functional contribution of N-acetyl-alpha-glucosaminidase to Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2998-3012页

作者： Yuan Zhao Yidan Zhang xin Liu Jian Zhang Ya Gao Shuyue Li Cui chang Xiang Liu Guofeng Yang Department of Geriatrics Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Department of Neurosurgery The Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina

Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease *** proteins,DNA,mRNA,and lipids carried by exosomes reflect intracellular changes,and thus can serve as biomarkers for a variety of *** this study,we investigated alterations in the protein content of plasma exosomes derived from patients with Parkinson’s disease and the potential therapeutic roles of these proteins in Parkinson’s *** a tandem mass tag-based quantitative proteomics approach,we characterized the proteomes of plasma exosomes derived from individual patients,identified exosomal protein signatures specific to patients with Parkinson’s disease,and identified N-acetyl-alpha-glucosaminidase as a differentially expressed protein.N-acetyl-alpha-glucosaminidase expression levels in exosomes from the plasma of patients and healthy controls were validated by enzyme-linked immunosorbent assay and western *** results demonstrated that the exosomal N-acetyl-alpha-glucosaminidase concentration was not only lower in Parkinson’s disease,but also decreased with increasing Hoehn-Yahr stage,suggesting that N-acetyl-alpha-glucosaminidase could be used to rapidly evaluate Parkinson’s disease ***,western blot and immunohistochemistry analysis showed that N-acetyl-alpha-glucosaminidase levels were markedly reduced both in cells treated with 1-methyl-4-phenylpyridinium and cells overexpressingα-synuclein compared with control ***,N-acetyl-alpha-glucosaminidase overexpression significantly increased cell viability and inhibitedα-synuclein expression in 1-methyl-4-phenylpyridinium-treated *** together,our findings demonstrate for the first time that exosomal N-acetyl-alpha-glucosaminidase may serve as a biomarker for Parkinson’s disease diagnosis,and that N-acetyl-alpha-glucosaminidase may reduceα-synuclein expression and 1-methyl-4-phenylpyridinium-induced n

关键词： biomarker diagnosis exosomes N-acetyl-alpha-glucosaminidase Parkinson’s disease proteomic α-synuclein

中华民族视觉形象的文化叙事及实践——基于文化形象学的论析

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新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 112-121页

作者：令小雄苗昕西北师范大学马克思主义学院教育部高校思想政治工作队伍培训研修中心(西北师范大学) 甘肃兰州730070

文本基于多维度理论系统梳理中华民族视觉形象的文化意蕴、内涵质态与构建策略,为铸牢中华民族共同体意识提供理论基础。一是运用文化符号学理论解析中华民族视觉形象的意涵及其历史演变,探赜“和合共生,合谐共美”价值理想承载的多元... 详细信息

文本基于多维度理论系统梳理中华民族视觉形象的文化意蕴、内涵质态与构建策略,为铸牢中华民族共同体意识提供理论基础。一是运用文化符号学理论解析中华民族视觉形象的意涵及其历史演变,探赜“和合共生,合谐共美”价值理想承载的多元一体文化格局,通过提炼核心符号,揭示视觉形象塑造在铸牢中华民族共同体意识中的重要作用。二是采用历史唯物主义方法论考察中华民族视觉形象在不同历史时期的构建与传播路径,通过文化形象考古学和文献学剖析视觉形象文化功能转变与价值重塑过程,探讨其在凝聚民族力量、强化国家认同中的重要意义。三是引入文化哲学、文化心理学视角分析视觉形象在增强社会凝聚力和心理认同中的内在机制,探究视觉符号通过激活集体记忆和情感共鸣、唤起民族自豪感和共同体意识成为社会整合的重要媒介。四是基于文化形象学视角提出构建中华民族视觉形象的策略:从中华文化形象本体论和认识论出发,提炼具有代表性的符号,利用现代数智科技和新媒体创新视觉形象的表达与传播,注重文化形象多样性的辩证统一,发掘整合各民族形象文化元素的共同意识。

关键词：中华民族视觉形象国家形象文化形象认同文化传播

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong miao Michael S.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第01期 201-208页

作者： Hui-Feng Wang Wen-Jie Shi Yu-xin Yang Bao-Xia Dong Tong-Bu Lu Di-chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

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Inspires effective alternatives to backpropagation:predictive coding helps understand and build learning

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Neural Regeneration Research 2025年第11期20卷 3215-3216页

作者： Zhenghua Xu miao Yu Yuhang Song School of Health Sciences and Biomedical Engineering Hebei University of TechnologyTianjinChina Department of Computer Science University of OxfordOxfordUK

Artificial neural networks are capable of machine learning by simulating the hiera rchical structure of the human *** enable learning by brain and machine,it is essential to accurately identify and correct the prediction errors,referred to as credit assignment(Lillicrap et al.,2020).It is critical to develop artificial intelligence by understanding how the brain deals with credit assignment in neuroscience.

关键词： assignment learning enable

Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： Yifan miao Li Zhao Yajun Zhang Zhe Yuan Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and Quantum Computing Fudan University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

关键词： neuromorphic computing spintronics magnetic tunnel junction neural networks