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Constrained adaptive neural network control of an MIMO aeroelastic system with input nonlinearities

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Chinese Journal of Aeronautics 2017年第2期30卷 796-806页

作者： Gou Yiyong Li Hongbo Dong Xinmin liu zongcheng Aeronautics and Astronautics Engineering College Air Force Engineering University Xi'an 710038 China

A constrained adaptive neural network control scheme is proposed for a multi-input and multi-output（MIMO） aeroelastic system in the presence of wind gust,system uncertainties,and input nonlinearities consisting of input saturation and *** regard to the input nonlinearities,the right inverse function block of the dead-zone is added before the input nonlinearities,which simplifies the input nonlinearities into an equivalent input *** deal with the equivalent input saturation,an auxiliary error system is designed to compensate for the impact of the input ***,uncertainties in pitch stiffness,plunge stiffness,and pitch damping are all considered,and radial basis function neural networks（RBFNNs） are applied to approximate the system *** combination with the designed auxiliary error system and the backstepping control technique,a constrained adaptive neural network controller is designed,and it is proven that all the signals in the closed-loop system are semi-globally uniformly bounded via the Lyapunov stability analysis ***,extensive digital simulation results demonstrate the effectiveness of the proposed control scheme towards flutter suppression in spite of the integrated effects of wind gust,system uncertainties,and input nonlinearities.

关键词： Aeroelastic system Constrained control Flutter suppression Input nonlinearities RBFNNs

A lunar time scale from the perspective of the Moon’s dynamic evolution

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Science China Earth Sciences 2024年第1期67卷 234-251页

作者： Dijun GUO Jianzhong liu James WHEAD Fuqin ZHANG zongcheng LING Shengbo CHEN Jianping CHEN Xiaozhong DING Jinzhu JI Ziyuan OUYANG State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Center for Lunar and Planetary Sciences Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Department of Earth Environmental and Planetary SciencesBrown UniversityProvidence RI 02912USA Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China College of Geoexploration Science and Technology Jilin UniversityChangchun 130026China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China School of Resources and Environmental Engineering Inner Mongolia University of TechnologyHohhot 010051China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China

A geologic time scale is a chronological system that separates the geological strata of a planetary body into different units in temporal sequence and shows its progressive *** time scale of the Moon was established a half-century ago during the telescopic-early Apollo exploration era,using data with limited spatial coverage and *** past decades have seen a wide array of studies,which have significantly extended our understanding of global lunar geologic *** on a comprehensive review of lunar evolution with respect to the dynamical changes,we propose two major updates to the current lunar time scale paradigm to include the evolution of both endogenic and exogenic dynamic forces now known to have influenced early lunar ***,based on the temporal interplay of exogenic and endogenic processes in altering the Moon,we defined three Eon/Eonothem-level units to represent three dynamical evolutionary ***,the pre-Nectarian System is redefined and divided as the magma ocean-era Magma-oceanian System and the following Aitkenian System beginning with the South Pole-Aitken *** ejecta of this basin,Das Formation,was deposited on the primordial lunar crust as the oldest stratum produced from exogenic *** updated lunar time scale,facilitated by the post-Apollo exploration and research advances,provides an integrated framework to depict the evolution of the Moon and has important implications for the geologic study of other terrestrial planets.

关键词： The Moon Geologic time scale Evolution history Endogenic process Exogenic process

Adaptive Tracking Control for Pure-feedback Nonlinear Systems with Semi-bounded Non-affine Functions and Dead-zone

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Adaptive Tracking Control for Pure-feedback Nonlinear System...

基于CEEMD与改进的ELM旋转整流器故障诊断

第三十九届中国控制会议

作者： Wenqian Zhang Wenhan Dong zongcheng liu Yang Zhou Haoming Feng College of Aeronautics Engineering Air Force Engineering University

An adaptive tracking control approach is presented for pure-feedback systems with semi-bounded non-affine functions and dead-zone. The strictive bounded conditions are relaxed by the semi-bounded for continuous non-affine function, and then an adaptive filter is investigated by employing the dynamic surface control technique and invariant set theory. Furthermore, the actual control scheme with dead-zone is considered based on backstepping structure to eventually guarantee the controllability, and then the robust compensator is designed to reduce the influence caused by uncertainties and disturbances. Moreover, the result shows that all the closed-loop signals are bounded and the tracking error can asymptotically converge to a residual set. Finally, a numerical simulation example is stated to demonstrate the feasibility of the proposed scheme.

关键词： Adaptive tracking control dynamic surface control pure-feedback systems dead-zone

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北京航空航天大学学报 2023年第5期49卷 1166-1175页

作者：朱佩荣刘勇智刘棕成陈俊柏聂恺空军工程大学研究生院西安710038 空军工程大学航空工程学院西安710038

针对目前应用于航空发电机旋转整流器故障诊断中的人工智能算法存在诊断速度慢、参数选取困难等问题,提出一种基于互补式集合经验模态分解(CEEMD)与樽海鞘优化的极限学习机(SSA-ELM)故障诊断方法。在有限元软件Maxwell与Simplorer中搭... 详细信息

针对目前应用于航空发电机旋转整流器故障诊断中的人工智能算法存在诊断速度慢、参数选取困难等问题,提出一种基于互补式集合经验模态分解(CEEMD)与樽海鞘优化的极限学习机(SSA-ELM)故障诊断方法。在有限元软件Maxwell与Simplorer中搭建三级式电机模型,采集励磁电流信号,利用CEEMD将励磁电流信号分解为一系列模态分量,构建故障特征参量,再通过樽海鞘群算法(SSA)优化极限学习机的训练参数ω和b,并对故障进行诊断,最后通过实验平台验证所提方法。结果证明了三级式同步电机有限元模型的有效性,所提方法相校于现有方法,具有更高的故障诊断准确率与分类速度。

关键词：互补式集合经验模态分解极限学习机旋转整流器故障诊断有限元樽海鞘群算法

Approximation-Based Adaptive Asymptotic Quantized Control of Uncertain Non-Affine Nonlinear Dynamics

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Approximation-Based Adaptive Asymptotic Quantized Control of...

第三十九届中国控制会议

作者： Ning Wang Ying Wang Xiaolin Wang Fan Zhang Jie Li Xiangyu Shi zongcheng liu Department of Equipment Management and UAV Engineering College Air Force Engineering University School of Aeronautics and Astronautics (Shenzhen) Sun Yat-sen University Aeronautics Engineering College Air Force Engineering University

This article addresses the asymptotic tracking problem for an extended class of switched non-affine nonlinear systems subject to input quantization. By contrast with the-state-of-theart, the most advanced peculiarity of this design lies in achieving asymptotic tracking, and considering non-smooth behaviors（*** dynamics and input quantization）. To pursue this,a error compensation term is designed for compensating the approximation and quantization errors. A common lyapunov function method is exploited to handle switching ***, the restrictive differentiable assumption on non-affine functions is removed but simply taken to be semi-bounded and continuous. It is analytically shown that the output tracking error can converge to zero asymptotically after choosing appropriate design parameters. Comparative simulations have been conducted to verify the effectiveness of the proposed methodology.

关键词： Asymptotic tracking switching dynamics nonaffine systems input quantization

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某乘用车匀速行驶车内轰鸣声分析与控制

重庆理工大学学报（自然科学） 2018年第11期32卷 29-34页

作者：刘宗成颜伏伍李进东风小康汽车有限公司汽车技术中心重庆400039

以某乘用车匀速行驶车内轰鸣声为研究对象,分析了乘用车车内轰鸣声的产生机理、影响因素及控制方法,阐述了研究对象产生的背景和现象特征,通过试验测试、频谱分析、传递路径分析、CAE仿真计算等研究分析方法,确定匀速行驶车内轰鸣声的... 详细信息

以某乘用车匀速行驶车内轰鸣声为研究对象,分析了乘用车车内轰鸣声的产生机理、影响因素及控制方法,阐述了研究对象产生的背景和现象特征,通过试验测试、频谱分析、传递路径分析、CAE仿真计算等研究分析方法,确定匀速行驶车内轰鸣声的激励源来自动力总成2阶振动激励,振动能量经传动轴和前悬架传递到车身,引起车身顶盖结构共振,最终在车内形成轰鸣声和压耳感。提出了优化车身结构和调整动力总成动力匹配策略相结合的优化控制方法。对实施优化方案的车辆进行主观评价和试验测试,结果表明:该方案解决了车内轰鸣声问题。

关键词：噪声振动试验测试仿真计算优化控制

Return to the Moon:New perspectives on lunar exploration

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Science Bulletin 2024年第13期69卷 2136-2148页

作者： Yangting Lin Wei Yang Hui Zhang Hejiu Hui Sen Hu Long Xiao Jianzhong liu Zhiyong Xiao Zongyu Yue Jinhai Zhang Yang liu Jing Yang Honglei Lin Aicheng Zhang Dijun Guo Sheng Gou Lin Xu Yuyang He Xianguo Zhang Liping Qin zongcheng Ling Xiongyao Li Aimin Du Huaiyu He Peng Zhang Jinbin Cao Xianhua Li Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory for Mineral Deposits Research and School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China Institute of Geochemistry Chinese Academy of SciencesGuiyang 550002China Planetary Environmental and Astrobiological Research Laboratory School of Atmospheric SciencesSun Yat-sen UniversityZhuhai 519082China National Space Science Center Chinese Academy of SciencesBeijing 100190China Deep Space Exploration Laboratory/CAS Key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of ChinaHefei 230026China Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China Technology and Engineering Center for Space Utilization Chinese Academy of SciencesBeijing 100094China School of Space and Environment Beihang UniversityBeijing 100191China

Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity’s exploration of deep *** the past decade,the Chinese Lunar Exploration Program(CLEP),also known as the Chang’e(CE)Project,has achieved remarkable *** has successfully developed and demonstrated the engineering capability required to reach and return from the lunar ***,the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon,along with the collection of the youngest volcanic samples from the Procellarum KREEP *** achievements have significantly enhanced our understanding of lunar *** on this success,China has proposed an ambitious crewed lunar exploration strategy,aiming to return to the Moon for scientific exploration and *** plan encompasses two primary phases:the first crewed lunar landing and exploration,followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar *** the limitations of current lunar exploration efforts and China’s engineering and technical capabilities,this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic *** study refines fundamental lunar scientific questions that could lead to significant breakthroughs,considering the respective engineering and technological *** research lays a crucial foundation for defining the objectives of future lunar exploration,emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

关键词： Crewed lunar exploration Water and volatiles Composition and structure of lunar interior Volcanic activity and evolution of lunar mantle Space weathering and radiation environments Exploration technology

福建省德化县肖坂-双旗山矿区韧性剪切带型金矿床成因初探

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福建冶金 2017年第3期46卷 1-3,8页

作者：刘宗成福建省197地质大队福建泉州362000

肖坂-双旗山金矿床产于元古代变质岩和中生代火山岩,矿床严格受区内韧性剪切带控制,在韧性剪切带、侵入岩接触带、构造破碎带等构造有利部位富集成矿,形成韧性剪切带型金矿。矿床成因为陆相火山岩型金矿和变质碎屑岩中热液型金矿。大岭... 详细信息

肖坂-双旗山金矿床产于元古代变质岩和中生代火山岩,矿床严格受区内韧性剪切带控制,在韧性剪切带、侵入岩接触带、构造破碎带等构造有利部位富集成矿,形成韧性剪切带型金矿。矿床成因为陆相火山岩型金矿和变质碎屑岩中热液型金矿。大岭组和南园组是区内金矿主要矿源层及赋矿层,区内岩脉的侵入活动为成矿提供了热液来源,是成矿的必要条件。

关键词：金矿床地质特征矿床成因

四川盆地中部上三叠统地层水成因与天然气地质意义

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石油勘探与开发 2009年第4期36卷 428-435页

作者：李伟杨金利姜均伟刘济民刘宗诚中国石油勘探开发研究院石油地质实验研究中心中国石油西南油气田公司川中油气矿中油测井技术服务有限责任公司

四川盆地中部上三叠统须家河组地层水矿化度大多较高,局部地区也存在中、低矿化度的地层水;地层水中几乎不含硫酸根离子,却含有大量的钡离子。须家河组地层水具有与侏罗系地层水类似的形成环境,而与下伏海相地层水形成环境差别较大。须... 详细信息

四川盆地中部上三叠统须家河组地层水矿化度大多较高,局部地区也存在中、低矿化度的地层水;地层水中几乎不含硫酸根离子,却含有大量的钡离子。须家河组地层水具有与侏罗系地层水类似的形成环境,而与下伏海相地层水形成环境差别较大。须家河组地层水具有较低的钠(钾)氯系数和较高的变质系数,展示出高变质地层水的特征;其中不含硫酸根离子,表明具有极好的还原条件或封闭条件。须家河组地层水具有原陆相沉积地层水受后期海相高浓度地层水改造的基本特点。储集层改造过程中应避免使用含大量硫酸根离子的地表水,更应尽量避免快速改变地层温度、压力与化学平衡,以免引起地层水中出现大量沉淀物而堵塞储集层孔隙与喉道,进而影响产能。

关键词：四川盆地上三叠统地层水成因地质意义