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Synchronous chirp mode extraction: A promising tool for fault diagnosis of rolling element bearings under varying speed conditions

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Chinese Journal of aeronautics 2022年第1期35卷 348-364页

作者： Xingxing JIANG Qiang HUANG Changqing SHEN Qian wang Kun XU jie LIU Juanjuan SHI Zhongkui ZHU school of Rail Transportation Soochow UniversitySuzhou 215131China Wenzheng College of Soochow university Suzhou 215104China College of Energy and Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Sclool of Hydropower and Infonnation Engineering Huazhong University of Science and TechnologyWuhan 430074China

As critical components in modern aerospace productions,rolling element bearings(REBs)generally work under varying speed conditions,which brings great challenges to their operating health *** novel time–frequency decomposition(TFD)algorithms are established recently to extract nonlinear features from the non-stationary signals effectively,which are promising for realizing fault diagnosis of REBs under varying speed ***,numerous personal experiences must be incorporated and the anti-noise performance of these methods needs to be further *** these issues,a synchronous chirp mode extraction(SCME)-based REB fault diagnosis method is proposed for the health monitoring of REBs under varying speed conditions in this *** mainly consists of following two parts.(a)The shaft rotational frequency(SRF)is initially estimated from the low-frequency band of the vibration ***,an adaptive refining strategy is incorporated to obtain a suitable bandwidth parameter.(b)A cycle-one-step estimation frame is constructed to extract synchronous modes from the envelope waveform of the vibration ***,a synchronous mode spectrum(SMS)is generated using the information of the extracted synchronous modes,which is a novel REBs fault diagnosis technique with tacholess and *** contrast to the current TFD algorithms,the proposed method needs fewer input parameters and owns a well anti-noise performance because there is no iterative optimization in the procedure of construction of *** a result,the health conditions of REBs are evaluated by detecting the exhibited features in the *** and experiments are conducted to validate the effectiveness of the proposed method in terms of REB fault *** results demonstrate that the proposed method outperforms the current TFD algorithm and the conventional order tracking technique for fault diagnosis of REB under varying speed conditions.

关键词： Envelope analysis Fault diagnosis Order tracking Rolling element bearing Varying speed

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语义级知识融合中的冲突消解方法

上海交通大学学报 2009年第11期43卷 1730-1733页

作者：胡晓胡洁彭颖红李晟曹兆敏上海交通大学机械与动力工程学院上海200240

为了解决存在逻辑联系的知识要素之间的冲突消解问题,定义了知识元的统一语义表达方式,将知识元之间的冲突按照粒度分为术语冲突、谓词冲突和语义冲突;提出了消解术语冲突的逻辑树融合法,消除谓词冲突的频率融合法以及用于消除语义冲突... 详细信息

为了解决存在逻辑联系的知识要素之间的冲突消解问题,定义了知识元的统一语义表达方式,将知识元之间的冲突按照粒度分为术语冲突、谓词冲突和语义冲突;提出了消解术语冲突的逻辑树融合法,消除谓词冲突的频率融合法以及用于消除语义冲突的句法融合法.实例证明,3种冲突消解算法能对存在冲突的知识元进行冲突消解.

关键词：知识融合冲突消解融合算法

Promoting Proton Migration Kinetics by Ni^(2+)Regulating Enables Improved Aqueous Zn-MnO_(2) Batteries

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Energy & Environmental Materials 2023年第2期6卷 252-261页

作者： jie Ji Jia Yao Yongchang Xu Houzhao Wan Bao Zhang Lin Lv Jingying Li Nengze wang Zhaohan Zheng Jun Zhang Guokun Ma Li Tao Hanbin wang Yi wang Hao wang Hubei Yangtze Memory Laboratories Wuhan 430205China School of MicroelectronicsHubei UniversityWuhan 430062China school of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China Center for Microscopy and Analysis Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The energy storage behaviors of MnO_(2) for aqueous Zn-MnO_(2) batteries mainly depend on the Zn^(2+)/H^(+)intercalation but are limited by poor ion/electron migration dynamics and ***,a strategy is proposed that promoting proton migration kinetics ameliorates H^(+)storage activity by introducing Ni^(2+)intoγ-MnO_(2)(Ni-MnO_(2)).Ni^(2+)can lower the diffusion barrier of H^(+)and selectively induce the ion intercalation,thereby alleviating the electrostatic interaction with the ***,Ni^(2+)enables the adjacent[MnO6]octahedrons to have better electron *** Ni-MnO_(2) exhibits superior rate performance(nearly four times specific capacity compared with MnO_(2))and ultra-long-cycle stability(100%of capacity retention after 11000 cycles at 3.0 A g^(-1)).The calculation indicates that the Ni-MnO_(2) allows H^(+)migrate rapidly along the one-dimensional tunnel due to reduction of the activation energy caused by Ni^(2+)regulating,thus achieving excellent reaction *** work brings great potential for the development of high-performance aqueous Zn-MnO_(2) batteries.

关键词： doping H^(+)storage ion/electron transport proton migration Zinc ion battery

Quasi‑Solid Electrolyte Interphase Boosting Charge and Mass Transfer for Dendrite‑Free Zinc Battery

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Nano-Micro Letters 2023年第4期15卷 223-237页

作者： Xueer Xu Yifei Xu Jingtong Zhang Yu Zhong Zhongxu Li Huayu Qiu Hao Bin Wu jie wang Xiuli wang Changdong Gu Jiangping Tu State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Provinceand School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Institute for Composites Science Innovation(InCSI)and State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101People’s Republic of China zhejiang Laboratory Hangzhou 311100People’s Republic of China Department of Engineering Mechanics School of Aeronautics and AstronauticsZhejiang UniversityHangzhou 310027People’s Republic of China

The practical applications of zinc metal batteries are plagued by the dendritic propagation of its metal anodes due to the limited transfer rate of charge and mass at the electrode/electrolyte *** enhance the reversibility of Zn metal,a quasi-solid interphase composed by defective metal-organic framework(MOF)nanoparticles(D-UiO-66)and two kinds of zinc salts electrolytes is fabricated on the Zn surface served as a zinc ions ***,anions in the aqueous electrolytes could be spontaneously anchored onto the Lewis acidic sites in defective MOF *** the synergistic effect between the MOF channels and the anchored anions,Zn^(2+)transport is prompted ***,such quasi-solid interphase boost charge and mass transfer of Zn^(2+),leading to a high zinc transference number,good ionic conductivity,and high Zn^(2+)concentration near the anode,which mitigates Zn dendrite growth ***,unprecedented average coulombic efficiency of 99.8%is achieved in the Zn||Cu cell with the proposed quasi-solid *** cycling performance of D-UiO-66@Zn||MnO_(2)(~92.9%capacity retention after 2000 cycles)and D-UiO-66@Zn||NH_(4)V_(4)O_(10)(~84.0%capacity retention after 800 cycles)prove the feasibility of the quasi-solid interphase.

关键词： Mass transfer Defect engineering Quasi-solid electrolyte interphase Zinc metal anode Zinc batteries

权变框架下我国能源与粮食安全:一个实时测度模型

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中国软科学 2024年第4期 154-165页

作者：朱庆缘孟波武良鹏潘应浩吴杰南京航空航天大学经济与管理学院能源软科学研究所江苏南京211106 南京信息工程大学应急与风险管理研究院江苏南京210044 中国科学技术大学管理学院安徽合肥230026

在逆全球化思潮抬头、局部冲突频发、全球性气候问题加剧多重压力叠加下,保障国家能源和粮食安全成为应对世界动态变革期间的重要任务。然而,当前多体现于基于底线思维的供应安全无法反映“安全”内涵的实时变化。基于函数型数据分析(F... 详细信息

在逆全球化思潮抬头、局部冲突频发、全球性气候问题加剧多重压力叠加下,保障国家能源和粮食安全成为应对世界动态变革期间的重要任务。然而,当前多体现于基于底线思维的供应安全无法反映“安全”内涵的实时变化。基于函数型数据分析(FDA)方法,构造权变框架下的安全评估体系,动态评估了我国30个省份2003—2019年的能源和粮食安全水平,并使用Function-on-Function(FOF)回归模型分析能源安全对粮食安全的实时影响。研究发现:能源安全的能源供应与运输安全和经济安全两个维度占比最大,环境安全比重逐渐提高;粮食安全的供应安全维度所占比重最大,生态安全的相关指标权重有所上升;随着能源安全与粮食安全内涵重心的改变,两者之间存在变动的非线性关系。

关键词：能源安全粮食安全函数型数据分析动态权重

Dynamic modeling and analysis of the looped space tether transportation system based on ANCF

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International Journal of Mechanical System Dynamics 2022年第2期2卷 204-213页

作者： jie Yang Qingtao wang Zhiyong Zhang Zhendong Liu Shidong Xu Gangqiang Li school of Science Nanjing University of Science and TechnologyNanjingChina Institute of Launch Dynamics Nanjing University of Science and TechnologyNanjingChina Shanghai Aerospace System Engineering Institute ShanghaiChina State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjingChina Department of Mechanical Engineering York UniversityTorontoCanada

A high‐fidelity multibody‐system dynamic model of the looped tether transportation system(L‐TTS)is proposed in this study to study its large deformation as well as large overall *** absolute nodal coordinate formulation(ANCF)‐based gradient‐deficient beam element is employed to establish the accurate model of the two flexible tethers subject to large *** relative movement of climbers along tethers is described by using the sliding joint model based on *** reduce the collision risks between tethers and climbers,two libration suppression strategies,namely,the decelerated motion of climbers relative to tethers and multiple climbers per tether are investigated in this *** numerical simulations not only validate the effectiveness of the two strategies in reducing the collision risks between climbers and tethers,the overall librations of L‐TTS,and the magnitudes of the longitudinal elastic force of tethers,but also verify the good performance of the high‐fidelity model proposed in this study for dynamic simulation of the L‐TTS in microgravity conditions.

关键词： looped tether transportation system high‐fidelity model absolute nodal coordinate formulation sliding joints libration suppression

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润湿性对脑白质水力渗透率的影响

Acta Mechanica Sinica 2024年第2期40卷 244-258页

作者：苏丽君雷杰超李振兴马驰原刘少宝 State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China MIIT Key Laboratory of Multifunctional Lightweight Materials and Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China Department of Neurosurgery Jinling HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing210002China

脑白质可被视为由神经轴突和组织液组成的周期性多孔介质,其水力渗透率反映了组织液在细胞外空间流动的阻力,在水分子运输和药物传递中起着关键作用.细胞外空间的典型宽度为纳米级,组织液流动是具有微尺度的润湿性问题,然而润湿性对渗... 详细信息

脑白质可被视为由神经轴突和组织液组成的周期性多孔介质,其水力渗透率反映了组织液在细胞外空间流动的阻力,在水分子运输和药物传递中起着关键作用.细胞外空间的典型宽度为纳米级,组织液流动是具有微尺度的润湿性问题,然而润湿性对渗透性的影响仍然不清楚.本研究将脑白质理想简化为一种周期性纤维多孔介质,考虑流体黏度和滑移边界,以量化润湿性对其水力渗透性的影响.发现流体有效黏度的减小和滑移长度的增加,会导致水力渗透率增大.还发现,对于方形排列的轴突纤维,润湿性对垂直水力渗透率的影响比对平行水力渗透率大;而对于六边形排列的轴突,影响则相反.研究结果可为脑水肿等脑水平衡紊乱疾病治疗及大脑药物传递提供理论指导.

关键词：药物传递脑白质神经轴突润湿性滑移边界脑水肿有效黏度组织液

倾转旋翼/机翼连续过渡状态气动性能仿真分析

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浙江大学学报（工学版） 2024年第4期58卷 857-866页

作者：王孟恬金台刘尧龙浙江大学航空航天学院浙江杭州310027

基于重叠网格,构建适用于连续倾转过渡状态模拟的数值计算框架.针对无人机中的2个重要部件——旋翼和机翼,模拟旋翼/机翼系统从固定翼模式倾转至直升机模式的过渡状态.采用雷诺平均方程,比较不同前进比下的气动性能变化,分析侧风风速对... 详细信息

基于重叠网格,构建适用于连续倾转过渡状态模拟的数值计算框架.针对无人机中的2个重要部件——旋翼和机翼,模拟旋翼/机翼系统从固定翼模式倾转至直升机模式的过渡状态.采用雷诺平均方程,比较不同前进比下的气动性能变化,分析侧风风速对过渡状态的气动性能影响.结果表明,机翼升阻力系数随着倾转角的增大而减小,变化程度随着前进比的增大而减小;旋翼拉力随着倾转角的增大而增大,变化程度随着前进比的增大而增大.当来流存在侧风情况时,机翼升阻力系数减小,在倾转角到65°后侧风风速较小时的机翼性能有一定提升.旋翼的拉力系数大小受侧风影响不大,但振荡幅度会因此增大.

关键词：倾转旋翼机过渡状态气动特性重叠网格数值仿真

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基于类电磁诱导透明效应的极化转换滤波器

物理学报 2024年第18期73卷 261-267页

作者：王哲飞吴杰万发雨曾庆生侯建强傅佳辉吴群宋明歆 Tayeb A.Denidni 南京信息工程大学电子与信息工程学院南京210044 南京航空航天大学航天学院南京210016 西安电子科技大学电子工程学院西安710071 哈尔滨工业大学电子与信息工程学院哈尔滨150001 海南大学应用技术学院儋州571737 魁北克大学国立科学研究院加拿大蒙特利尔H5A1K6

在太赫兹频段基于类电磁诱导透明效应(electromagnetically induced transparency,EIT)提出了一种高效率极化转化滤波器,通过非对称结构激励了多能级明模路径,在传统EIT干涉效应的基础上,获得了正交的圆极化转换窗口.通过两组具有相似... 详细信息

在太赫兹频段基于类电磁诱导透明效应(electromagnetically induced transparency,EIT)提出了一种高效率极化转化滤波器,通过非对称结构激励了多能级明模路径,在传统EIT干涉效应的基础上,获得了正交的圆极化转换窗口.通过两组具有相似共振频率的明模相互干涉产生透射窗口,然后构造非对称结构来实现TE和TM极化下的透射窗口偏移,从而实现双频点极化转换.该超材料的单元结构由4个开口T型金属谐振组成.通过分析表面电流分布、频率响应特性以及入射角特性,探究了其工作机理.研究结果显示,该设计在不同极化下实现了电磁诱导透明现象.随后,基于两个入射极化的EIT共振,在0.692 THz处实现了线极化到右旋圆极化转换和0.782 THz处实现了线极化到左旋圆极化转换,透射系数分别为0.7和0.68.这种基于EIT的极化转化具有低损耗和超薄的特点,在紧凑型天线、衍生雷达相控阵和军事工业探测器领域有潜在应用价值.

关键词：超材料电磁诱导透明效应极化转换滤波器