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A review of modeling,simulation,and control technologies of altitude ground test facilities for control application

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Chinese Journal of Aeronautics 2023年第9期36卷 38-62页

作者： Xitong PEI Xi WANG Jiashuai LIU Meiyin ZHU Zhihong DAN Ai HE keqiang miao Louyue ZHANG Zheng XU Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Science and Technology on Altitude Simulation Laboratory AECC Sichuan Gas Turbine EstablishmentMianyang 621703China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310023China Institute for Aero Engine Tsinghua UniversityBeijing 100084China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China

As the pivotal test equipment of aero-engines design,finalization,improvement,modification,etc.,the Altitude Ground Test Facilities(AGTF)plays an important role in the research and development of the *** the rapid development of advanced high-performance aeroengine,the increasing demand of high-altitude simulation test is driving AGTF to improve its test ability and level of automation and *** modeling method,simulation tool,and control technology are the key factors to support the improvement of the AGTF control *** main purpose of this paper is to provide an overview of modeling methods,simulation tools,and control technologies in AGTF control system for future ***,it reviews the evolution of AGTF in the world,from the early formative stage to integration ***,the mathematical modeling method of AGTF for control application is ***,the simulation tools used in the AGTF control system are overviewed from numerical simulation to hardware-in-loop simulation and further to semi-physical ***,the control technologies used in the AGTF control system are summarized from single-variable control to multivariable integrated control,and from classical control theory to modern control ***,recommendations for future research are ***,this review article provides extensive literature information for the modeling,simulation,and control design of AGTF for control application.

关键词： Altitude ground test facilities Control system Modeling and simulation Robust control Temperature and pressure control

Modified robust optimal adaptive control for flight environment simulation system with heat transfer uncertainty

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Chinese Journal of Aeronautics 2021年第2期34卷 420-431页

作者： Meiyin ZHU Xi WANG Xitong PEI Song ZHANG Zhihong DAN Nannan GU Shubo YANG keqiang miao Huairong CHEN Jiashuai LIU School of Energy and Power Engineering Beihang UniversityBeijing 100083China Collaborative Innovation Center for Advanced Aero Engine Bejing 100083China Science and Technology on Altitude Simulation Laboratory AECC(Aero Engine Corporation of China)Sichuan Gas Turbine EstablishmentMianyang 621000China

To solve the rapid transient control problem of Flight Environment Simulation System(FESS) of Altitude Ground Test Facilities(AGTF) with large heat transfer uncertainty and disturbance, a new adaptive control structure of modified robust optimal adaptive control is *** mathematic modeling of FESS is given and the influence of heat transfer is analyzed through energy view. To consider the influence of heat transfer in controller design, we introduce a matched uncertainty that represents heat transfer influence in the linearized system of FESS. Based on this linear system, we deduce the design of modified robust optimal adaptive control law in a general way. Meanwhile, the robust stability of the modified robust optimal adaptive control law is proved through using Lyapunov stability theory. Then, a typical aero-engine test condition with Mach Dash and Zoom-Climb is used to verify the effectiveness of the devised adaptive controller. The simulation results show that the designed controller has servo tracking and disturbance rejection performance under heat transfer uncertainty and disturbance;the relative steady-state and dynamic errors of pressure and temperature are both smaller than 1% and 0.2% respectively. Furthermore,the influence of the modification parameter c is analyzed through simulation. Finally, comparing with the standard ideal model reference adaptive controller, the modified robust optimal adaptive controller obviously provides better control performance than the ideal model reference adaptive controller does.

关键词： Altitude ground test facilities Flight environment simulation system Heat transfer Model reference adaptive control Optimal control modification Uncertainty

基于LMI的过渡态主控回路闭环控制律优化设计

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北京航空航天大学学报 2022年第5期48卷 841-854页

作者：缪柯强王曦朱美印北京航空航天大学能源与动力工程学院北京100083 先进航空发动机协同创新中心北京100083

针对涡扇发动机过渡态多变量控制设计难的问题,提出了一种基于抽功法在过渡态加减速线上的准稳态工作点处提取线性模型的方法,并在此基础上提出了一种过渡态主控回路闭环控制律的优化设计方法。通过功率输入和功率提取解决过渡态动态特... 详细信息

针对涡扇发动机过渡态多变量控制设计难的问题,提出了一种基于抽功法在过渡态加减速线上的准稳态工作点处提取线性模型的方法,并在此基础上提出了一种过渡态主控回路闭环控制律的优化设计方法。通过功率输入和功率提取解决过渡态动态特征提取难题,基于增益调度可作为非线性动态控制策略的基本原理,将稳态多变量控制规律的线性矩阵不等式(LMI)设计方法推广到涡扇发动机过渡态主控回路闭环控制的设计中,并通过最小化矩阵迹优化闭环极点配置。针对2种不同过渡态主控回路闭环控制策略,分别设计了最小化矩阵迹寻优的过渡态主控回路的多变量闭环控制律,并进行从慢车到中间状态的基于涡扇发动机非线性动态模型的双通道过渡态性能仿真验证,结果表明:方案1过渡态控制双通道N_(1)、N_(2)的调节时间不大于5.0 s,超调量不大于0.8%;方案2过渡态控制双通道π_(T)、N_(2)的调节时间不大于5.6 s,超调量不大于0.8%。

关键词：涡扇发动机过渡态主控回路增益调度线性矩阵不等式(LMI) 矩阵迹寻优

Netrin-1 signaling pathway mechanisms in neurodegenerative diseases

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Neural Regeneration Research 2025年第4期20卷 960-972页

作者： Kedong Zhu Hualong Wang keqiang Ye Guiqin Chen Zhaohui Zhang Department of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina Department of Neurology The First Hospital of Hebei Medical UniversityBrain Aging and Cognitive Neuroscience Laboratory of Heibei ProvinceShijiazhuangHebei ProvinceChina Faculty of Life and Health Sciences Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal *** profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic *** amounts of evidence highlight several key points:(1)Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer’s disease and Parkinson’s disease,and potentially,similar alterations occur in humans.(2)Genetic mutations of Netrin-1 receptors increase an individuals’susceptibility to neurodegenerative disorders.(3)Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function.(4)Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of *** findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative *** a comprehensive review of Netrin-1 signaling pathways,our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.

关键词： Alzheimer’s disease axon guidance colorectal cancer Netrin-1 receptors Netrin-1 signaling pathways Netrin-1 neurodegenerative diseases neuron survival Parkinson’s disease UNC5C

左心室舒张功能不全血清脑钠肽的改变及缬沙坦干预的作用

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临床内科杂志 2005年第5期22卷 311-313页

作者：徐上淼缪克强浙江省苍南县第二人民医院心内科 325802

目的　探讨左心室(左室)舒张功能不全患者血清脑钠肽(BNP)水平改变和诊断价值,以及缬沙坦干预的作用。方法　用酶联免疫法测定30例单纯左室舒张功能不全患者(LVDD组)、20例左室收缩功能不全伴或不伴舒张功能不全患者(LVSD组)、20例心功... 详细信息

目的　探讨左心室(左室)舒张功能不全患者血清脑钠肽(BNP)水平改变和诊断价值,以及缬沙坦干预的作用。方法　用酶联免疫法测定30例单纯左室舒张功能不全患者(LVDD组)、20例左室收缩功能不全伴或不伴舒张功能不全患者(LVSD组)、20例心功能正常者(对照组)以及LVDD组缬沙坦干预10周后的血清BNP浓度。结果　LVDD组BNP水平明显高于对照组(186. 9pg/ml±125. 1pg/ml对68. 9pg/ml±29. 3pg/ml,P0. 05 )。若左室收缩功能正常,BNP>120pg/ml判断单纯LVDD的敏感度为86. 7%,特异度为95%,阳性预告值为96. 3%,阴性预告值为82. 6%。缬沙坦治疗LVDD10周对BNP水平尚无明显影响(150. 1pg/ml±87. 5pg/ml对145. 9pg/ml±80. 2pg/ml,P>0. 05)。结论　血清BNP浓度在单纯LVDD患者亦明显升高,并有较好的诊断价值,缬沙坦治疗LVDD患者10周对BNP水平尚无明显影响。

关键词：左心室舒张功能不全脑钠肽缬沙坦

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

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

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