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Chinese Journal of Aeronautics 2021年第9期34卷 178-198页

作者： Qingxuan JIA bonan yuan Gang CHEN Yingzhuo FU School of Automation Beijing University of Posts and TelecommunicationsBeijing 100876China

Space manipulator with free-swinging joint failure simultaneously contains kinematic and dynamic coupling relationships,so it belongs to a new underactuated *** allow the manipulator to carry on tasks,an effective robust underactuated control method for the space manipulator with free-swinging joint failure is studied in this *** the effect of model uncertainty and joint torque disturbance,a robust underactuated control system based on the Terminal Sliding Mode Controller(TSMC)is designed,but two drawbacks are discussed:(A)Robustness depraves with eliminating chattering.(B)Control parameters are difficult to be determined under unknown uncertainty and *** improve the TSMC,the adaptive fuzzy controller is introduced to estimate the real effect of unknown uncertainty and disturbance according to deviations of sliding mode and its reaching *** estimated result is directly compensated into active joints *** simulation,the space manipulator with free-swinging joint executes tasks based on the TSMC and the Adaptive Fuzzy Terminal Sliding Mode Controller(AFTSMC)*** tasks can be finished with smaller joints torque and stronger robustness based on the ***,AFTSMC can serve as an effective robust control method for the space manipulator with free-swinging joint failure under unknown model uncertainty and torque disturbance.

关键词： Space manipulator Free-swinging joint failure Sliding mode control Adaptive fuzzy control Robust controllers

A multi-stage regulation strategy of space manipulators with a free-swinging joint failure

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Chinese Journal of Aeronautics 2021年第5期34卷 573-584页

作者： Gang CHEN Yingzhuo FU Qingxuan JIA bonan yuan Dan LIU School of Automation Beijing University of Posts and TelecommunicationsBeijing 100876China

To ensure tasks can be completed after a free-swinging joint failure occurs,a multi-stage regulation strategy of space manipulators is *** all terms of the dynamics equation,an evaluation model of the regulation ability(EMRA)of active joints over the fault joint is established based on the fuzzy *** then a multi-stage regulation strategy based on the EMRA is designed to regulate the fault *** strategy divides the regulation process into several stages,and select a certain active joint to regulative the fault joint in every *** this multi-stage regulation strategy,the fault joint can be regulated to the desired angle without huge torque on regulative *** simulation is carried out with a 7-DOF space manipulator,verifying the correctness and effectiveness of the multi-stage regulation *** strategy has three advantages:Coriolis and centrifugal terms are both considered for the first time in selecting the regulative joint,making the selection result more in line with the actual regulation process;The influence of the model uncertainty is eliminated in establishing the EMRA,making the evaluation of regulative ability more precise;The fault joint is successfully regulated to the desired angle without huge torque on regulative joints.

关键词： Free-swinging joint failure Fuzzy entropy Multi-stage regulation strategy Regulation ability Space manipulator

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空间机械臂关节失效瞬时力矩突变抑制

宇航学报 2018年第11期39卷 1209-1220页

作者：贾庆轩袁博楠陈钢刘鑫北京邮电大学自动化学院北京100876 北京空间飞行器总体设计部北京100094

针对空间机械臂执行负载操作任务突发关节失效引起的关节负载补偿力矩突变问题,建立了关节负载补偿力矩突变优化模型及求解方法。首先分析关节负载补偿力矩突变原因,以故障瞬间力矩突变量最小为目标,考虑突发关节故障,建立关节负载补偿... 详细信息

针对空间机械臂执行负载操作任务突发关节失效引起的关节负载补偿力矩突变问题,建立了关节负载补偿力矩突变优化模型及求解方法。首先分析关节负载补偿力矩突变原因,以故障瞬间力矩突变量最小为目标,考虑突发关节故障,建立关节负载补偿力矩突变优化模型;其次构造含有抑制系数及静力学可操作度梯度的关节力矩修正项,并构造最优抑制系数函数,求解关节力矩突变优化问题;最后通过仿真对关节负载补偿力矩突变优化方法的正确性和有效性展开验证。结果表明:通过搜索最优抑制系数,突发关节失效引起的关节负载补偿力矩突变可被有效抑制,平均抑制率高达89. 26%,且末端操作力精度不受影响,保证了空间机械臂负载操作任务安全可靠完成。

关键词：空间机械臂负载操作关节失效关节力矩突变抑制

The dopaminergic system and Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2495-2512页

作者： Yuhan Zhang yuan Liang Yixue Gu International Medical College Chongqing Medical UniversityChongqingChina College of Pharmacy Chongqing Medical UniversityChongqingChina Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of NeurologyChongqingChina

Alzheimer's disease is a common neurodegenerative disorder in older *** its prevalence,its pathogenesis remains unclea *** addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this *** is a crucial catecholaminergic neurotransmitter in the human ***-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical *** r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive *** review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related *** aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

关键词： adverse drug reaction Alzheimer's disease catecholamine dopamine receptor dopamine receptor heterodimers dopaminergic system neurodegenerative disease neurotransmitter signaling pathways traditional Chinese medicine treatment

Toward Analytical Homogenized Relaxation Modulus for Fibrous Composite Material with Reduced Order Homogenization Method

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Computers, Materials & Continua 2025年第1期82卷 193-222页

作者： Huilin Jia Shanqiao Huang Zifeng yuan HEDPS Center for Applied Physics and Technology(CAPT)Department of Mechanics and Engineering SciencePeking UniversityBeijing100871China State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100871China

In this manuscript,we propose an analytical equivalent linear viscoelastic constitutive model for fiber-reinforced composites,bypassing general computational *** method is based on the reduced-order homogenization(ROH)*** ROH method typically involves solving multiple finite element problems under periodic conditions to evaluate elastic strain and eigenstrain influence functions in an‘off-line’stage,which offers substantial cost savings compared to direct computational homogenization *** to the unique structure of the fibrous unit cell,“off-line”stage calculation can be eliminated by influence functions obtained *** the standard solid model to the ROH method enables the creation of a comprehensive analytical homogeneous viscoelastic constitutive *** method treats fibrous composite materials as homogeneous,anisotropic viscoelastic materials,significantly reducing computational time due to its analytical *** approach also enables precise determination of a homogenized anisotropic relaxation modulus and accurate capture of various viscoelastic responses under different loading *** sets of numerical examples,including unit cell tests,three-point beam bending tests,and torsion tests,are given to demonstrate the predictive performance of the homogenized viscoelastic ***,the model is validated against experimental measurements,confirming its accuracy and reliability.

关键词： Homogenized relaxation modulus viscoelastic standard solid model reduced order homogenization fibrous composite material

Optimal Scheduling of an Independent Electro-Hydrogen System with Hybrid Energy Storage Using a Multi-Objective Standardization Fusion Method

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Energy Engineering 2025年第1期122卷 63-84页

作者： SuliangMa ZeqingMeng Mingxuan Chen yuan Jiang School of Electrical and Control Engineering North China University of TechnologyBeijing100144China ChinaThree Gorges Technology Co. Ltd.Beijing100032China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China

In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is ***,it presents a challenge due to the significant deviations in values ofmultiple optimization objective functions caused by their physical *** deviations seriously affect the scheduling process.A novel standardization fusion method has been established to address this issue by analyzing the variation process of each objective function’s *** optimal scheduling results of IEHS with HESS indicate that the economy and overall energy loss can be improved 2–3 times under different optimization *** proposed method better balances all optimization objective functions and reduces the impact of their *** the cost of BESS decreases by approximately 30%,its participation deepens by about 1 ***,if the price of the electrolyzer is less than 15￥/kWh or if the cost of the fuel cell drops below 4￥/kWh,their participation will increase *** study aims to provide a more reasonable approach to solving multi-objective optimization problems.

关键词： Electro-hydrogen system multi-objective optimization standardization method hybrid energy storage system

Sex differences in aging and injured brain

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Neural Regeneration Research 2025年第10期20卷 2901-2902页

作者： Jordan N.Williamson yuan Yang University of Illinois Urbana-Champaign Grainger College of EngineeringDepartment of BioengineeringUrbanaILUSA Carle Foundation Hospital Stephenson Family Clinical Research InstituteClinical Imaging Research CenterUrbanaILUSA University of Illinois Urbana-Champaign Beckman Institute for Advanced Science and TechnologyUrbanaILUSA Northwestern University Department of Physical Therapy and Human Movement SciencesChicagoILUSA

Background:The prevalence,age of onset,and symptomatology of traumatic brain injury,stroke,and neurodegenerative diseases(such as Alzheimer’s disease(AD),Parkinson’s disease,amyotrophic lateral sclerosis,and Huntington’s disease)differ substantially between males and *** higher prevalence of these brain disorders has been attributed to females having a greater longevity compared with *** one of the greatest risk factors of acquired brain injury(such as stroke,traumatic brain injury caused by fall)and neurodegenerative disease is age.

关键词： Huntington prevalence traumatic

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

Peripheral mitochondrial DNA as a neuroinflammatory biomarker for major depressive disorder

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Neural Regeneration Research 2025年第6期20卷 1541-1554页

作者： Jinmei Ye Cong Duan Jiaxin Han Jinrong Chen Ning Sun yuan Li Tifei yuan Daihui Peng Division of Mood Disorder Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Shanghai Key Laboratory of Psychotic Disorders Brain Health InstituteNational Center for Mental DisordersShanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina

In the pathogenesis of major depressive disorder, chronic stress-related neuroinflammation hinders favorable prognosis and antidepressant response. Mitochondrial DNA may be an inflammatory trigger, after its release from stress-induced dysfunctional central nervous system mitochondria into peripheral circulation. This evidence supports the potential use of peripheral mitochondrial DNA as a neuroinflammatory biomarker for the diagnosis and treatment of major depressive disorder. Herein, we critically review the neuroinflammation theory in major depressive disorder, providing compelling evidence that mitochondrial DNA release acts as a critical biological substrate, and that it constitutes the neuroinflammatory disease pathway. After its release, mitochondrial DNA can be carried in the exosomes and transported to extracellular spaces in the central nervous system and peripheral circulation. Detectable exosomes render encaged mitochondrial DNA relatively stable. This mitochondrial DNA in peripheral circulation can thus be directly detected in clinical practice. These characteristics illustrate the potential for mitochondrial DNA to serve as an innovative clinical biomarker and molecular treatment target for major depressive disorder. This review also highlights the future potential value of clinical applications combining mitochondrial DNA with a panel of other biomarkers, to improve diagnostic precision in major depressive disorder.

关键词： biomarker cytokine exosomes inflammasome major depressive disorder microglia mitochondrial DNA mitochondrial dysfunction neuroinflammation Toll-like receptor

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng Li Meifeng Cai Shengjun Miao yuan Li Yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification