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Acta Mechanica Sinica 2024年第7期40卷 181-194页

作者： Hao Niu Chao Li Anhua Chen Guangfu Bin lun long Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment Hunan University of Science and TechnologyXiangtan 411201China AECC HAPRI Key Laboratory of Aero-engine Vibration Technology Zhuzhou 412000China

Ice causes impact damage to different positions of the compressor blade,destroys the structural integrity of the rotor structure,and then causes unbalanced failure and even causes nonlinear vibration accidents such as collision and friction,which affects the execution of helicopter *** investigate the influence of impact position on the damage form and dynamic response of blades during ice impact,a dynamic model by finite element-smooth particle fluid dynamic coupling method is *** ice impact damage experiment of the TC4 plate based on the air gun experimental platform was carried out to verify the reliability of the simulation *** damage of compressor blades impacted by ice from different positions under static and design speed of 45000 r/min is *** research results indicate that under static conditions,the damage caused by ice impact from the leading edge blade tip to the leading edge blade root first increases and then decreases,with the maximum damage occurring at the 66.7%blade height position on the leading *** the design speed,the closer the impact locations are to the leaf tip,the greater the damage is,and the plastic damage,equivalent stress,and kinetic energy loss of the ice impact are lower than the blade static *** research conclusion can provide theoretical reference and data support for the design of structural strength and protection of compressor blades in turboshaft engines.

关键词： Turboshaft engine Compressor blade Ice Impact damage simulation Dynamic response

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基于随机森林回归的电离层幅度闪烁指数预测

计算机工程与设计 2024年第8期45卷 2350-2356页

作者：钟伦珑刘明远胡铁乔刘永玉中国民航大学智能信号与图像处理天津市重点实验室天津300300

为满足低成本、高精度的电离层闪烁监测需求,提出一种基于随机森林回归的闪烁指数预测模型。在卫星导航接收机输出信息基础上,计算电离层结构状态参数,形成输入参数,并进行参数筛选构建训练数据集,结合专用型电离层闪烁监测接收机观测... 详细信息

为满足低成本、高精度的电离层闪烁监测需求,提出一种基于随机森林回归的闪烁指数预测模型。在卫星导航接收机输出信息基础上,计算电离层结构状态参数,形成输入参数,并进行参数筛选构建训练数据集,结合专用型电离层闪烁监测接收机观测到的闪烁指数,训练生成基于随机森林回归的幅度闪烁指数预测模型。实验结果表明,与传统电离层幅度闪烁指数计算方法相比,随机森林回归模型预测得到的闪烁指数相关性更强、精度更高。

关键词：幅度闪烁指数随机森林回归电离层结构状态载噪比电离层闪烁监测全球导航卫星系统预测模型

Electrochemical Analysis of Single Glucose Oxidase with a Nanopipette

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Chemical Research in Chinese Universities 2024年第2期40卷 272-278页

作者： WANG Yongyong MA Hui long Yi-Tao YING Yi-lun School of Chemistry and Chemical Engineering Molecular Sensing and Imaging Center(MSIC)Nanjing UniversityNanjing210023P.R.China

Nanopore-based electrochemical technique is a promising tool for detecting single ***,detecting single proteins using a nanopipette in their native state without labeling is challenging due to the rapid translocation,which results in an inefficient signal *** our study,we finely tuned the driving force equilibrium between electrophoretic force(EPF)and electroosmotic flow(EOF)inside the nanopipette for efficient sensing of single glucose oxidase(GOD)*** duration time of GOD within the nanopipette is extended to about 4 *** strategy provided clear ionic current signals with a signal-to-noise ratio of *** EPF increased in the direction opposite to the motion of GOD,we observed a nonlinear growth in GOD’s duration *** extended the duration to about 4.4 times longer at−1000 mV compared to at−800 ***,nanopore-based electrochemical sensing could be used for single GOD molecule analysis as an ultrasensitive method.

关键词： Nanopore Single-molecule analysis Glucose oxidase Electrophoretic force Electroosmotic flow

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单通道最优恒模自适应干扰抑制方法

电子与信息学报 2011年第5期33卷 1126-1130页

作者：石庆研吴仁彪钟伦珑西安电子科技大学雷达信号处理国防重点实验室西安710071 中国民航大学智能信号与图像处理天津市重点实验室天津300300

针对民航地空通信中常见干扰具有恒定包络的特点,该文提出了一种基于单通道最优恒模算法的自适应干扰抑制方法。该方法利用干扰信号的恒模特性,采用非线性最小二乘的方法对干扰信号的幅度与相位进行估计,并将其与接收到的混合信号相减,... 详细信息

针对民航地空通信中常见干扰具有恒定包络的特点,该文提出了一种基于单通道最优恒模算法的自适应干扰抑制方法。该方法利用干扰信号的恒模特性,采用非线性最小二乘的方法对干扰信号的幅度与相位进行估计,并将其与接收到的混合信号相减,从而实现了恒模干扰信号的抑制。该方法与现有民航地空通信系统具有较好的兼容性,无需额外增加通道,且避免了一般自适应干扰抑制算法中的收敛问题。仿真和实测数据的处理结果表明该方法具有较好的干扰抑制效果。

关键词：民航通信单通道最优恒模算法自适应干扰抑制恒模阵列非线性最小二乘

Ergodicity of 3D Stochastic Burgers Equation

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Acta Mathematica Sinica,English Series 2024年第2期40卷 498-510页

作者： Zhao DONG Jiang lun WU Guo Li ZHOU RCSDS Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China Department of Mathematics Computational FoundrySwansea UniversitySwansea SA18ENUK College of Mathematics and Statistics Chongqing UniversityChongqing 400044P.R.China

3D Burgers equation is an important model for *** is natural to expect the long-time behaviour for this hydrodynamics ***,there is no result about the long-time behaviour for this deterministic ***,if the system is perturbed by stochastic noise,we establish the existence and uniqueness of invariant measure for 3D stochastic Burgers equation.

关键词： 3D stochastic Burgers equations maximum principle ergodicity

Dimensional regulation in gigantic molybdenum blue wheels featuring{(W)Mo_(5)}motifs for enhanced proton conductivity

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Nano Research 2024年第9期17卷 8261-8268页

作者： Yu-lun Wu Jing Du Hai-Ying Zhang Ming-Jun Hou Qiao-Yue Li Wei-Chao Chen Kui-Zhan Shao Bo Zhu Chao Qin Xin-long Wang Zhong-Min Su Key Laboratory of Polyoxometalate and Reticular Material Chemistry of Ministry of Education Department of ChemistryNortheast Normal UniversityChangchun 130024China Hebei Key Laboratory of Organic Functional Molecules National Demonstration Center for Experimental Chemistry EducationTesting and Analysis CenterCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China

Dimensional regulation in polyoxometalates is an effective strategy during the design and synthesis of polyoxometalates-based high proton conductors,but it is not available to ***,the precise regulation of dimensionality has been realized in an unprecedented gigantic molybdenum blue wheel family featuring pentagonal{(W)Mo5}motifs through optimizing the molar ratio of Mo/W,including[Gd_(2)Mo_(124)W_(14)O_(422)(H_(2)O)62]38-(0D-{Mo_(124)W_(14)},1),[Mo_(126)W_(14)O441(H_(2)O)51]^(70-)(1D-{Mo_(126)W_(14)}n,2),and[Mo_(124)W_(14)O_(430)(H_(2)O)50]60-(2D-{Mo_(124)W_(14)}n,3).Such important{(W)Mo5}structural motif brings new reactivity into gigantic Mo blue *** are different numbers and sites of{Mo2}defects in each wheel-shaped monomer in 1-3,which leads to the monomers of 2 and 3 to form 1D and 2D architectures via Mo-O-Mo covalent bonds driven by{Mo2}-mediated H_(2)O ligands substitution process,respectively,thus achieving the controllable dimensional *** expected,the proton conductivity of 3 is 10 times higher than that of 1 and 1.7 times higher than that of *** continuous proton hopping sites in 2D network are responsible for the enhanced proton conductivity with lower activation *** study highlights that this dimensional regulation approach remains great potential in preparing polyoxometalates-based high proton conductive materials.

关键词： polyoxometalate molybdenum blue wheels Mo/W mixed-addenda polyoxometalates dimensional regulation proton conduction

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地空通信中持续干扰抑制系统的设计与实现

计算机工程与设计 2018年第12期39卷 3667-3673页

作者：钟伦珑胡铁乔中国民航大学智能信号与图像处理天津市重点实验室天津300300

为解决地空通信中的无线电干扰问题,保障飞行安全,结合民航通信中持续干扰的特点,提出基于最小二乘的持续干扰自适应抑制方法。分析双通道系统数学模型,利用信号的时域特点设计干扰抑制器加权矢量的更新方法,利用协方差矩阵的特征值之... 详细信息

为解决地空通信中的无线电干扰问题,保障飞行安全,结合民航通信中持续干扰的特点,提出基于最小二乘的持续干扰自适应抑制方法。分析双通道系统数学模型,利用信号的时域特点设计干扰抑制器加权矢量的更新方法,利用协方差矩阵的特征值之比自动识别与判断信号中是否仅有持续干扰。在此基础上,采用数字信号处理器DSP芯片和现场可编程门阵列FPGA芯片设计并实现持续干扰抑制系统。仿真与实验结果表明,该方法可以有效地抑制地空通信中的持续干扰。

关键词：自适应干扰抑制持续干扰抑制系统数字信号处理器现场可编程门阵列民航地空通信

镜像疗法在脑卒中偏瘫患者运动康复中的研究进展

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中国康复理论与实践 2018年第6期24卷 659-666页

作者：陈英伦白玉龙复旦大学附属华山医院康复医学科上海市200040

镜像疗法最先用于幻肢痛的治疗,后广泛应用于脑卒中、周围神经损伤等。镜像疗法的机制包括镜像神经元系统,视觉反馈-运动观察,运动通路易化以及经胼胝体连接、抑制通路等。大多数研究认为脑卒中患者患肢对侧的肢体(健侧)运动引起运动同... 详细信息

镜像疗法最先用于幻肢痛的治疗,后广泛应用于脑卒中、周围神经损伤等。镜像疗法的机制包括镜像神经元系统,视觉反馈-运动观察,运动通路易化以及经胼胝体连接、抑制通路等。大多数研究认为脑卒中患者患肢对侧的肢体(健侧)运动引起运动同侧大脑半球皮质激活,锥体束传导特性改变,进而影响受支配肌肉的运动和功能恢复,可不同程度地改善脑卒中患者运动缺陷、加强运动功能(如手指运动、腕屈伸活动)。

关键词：脑卒中镜像疗法运动功能康复综述

Temporal and spatial variations hydrochemical components and driving factors in Baiyangdian Lake in the Northern Plain of China

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Journal of Groundwater Science and Engineering 2024年第3期12卷 293-308页

作者： Tian-lun Zhai Qian-qian Zhang long Wang Hui-wei Wang Hebei and China Geological Survey Key Laboratory of Groundwater Remediation Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesShijiazhuang 050061China

Understanding the temporal and spatial variation of hydrochemical components in large freshwater lakes is crucial for effective management and *** this study,we identify the temporalspatial characteristics and driving factors of the hydrochemical components in Baiyangdian Lake using geochemical methods(Gibbs diagram,Piper diagram and End-element diagram of ion ratio)and multivariate statistical techniques(Principal component analysis and Correlation analysis).16 sets of samples were collected from Baiyangdian Lake in May(normal season),July(flood season),and December(dry season)of *** indicate significant spatial variation in Nat,ci,SO and NO,,suggesting a strong influence of human *** concentrations exhibit greater seasonal variation in the dry season compared to the flood season,while the concentrations of the four anions show inconsistent seasonal changes due to the combined effects of river water chemical composition and human *** hydrochemical type of Baiyangdian Lake is primarily HCO,***,Mg*and HCO,originate mainly from silicate and carbonate rock dissolution,while Kt,Nat and CI originate mainly from sewage and salt dissolution in ***42 may mainly stem from industrial wastewater,while NO,primarily originates from animal feces and domestic *** the use of Principal Component Analysis,it is identified that water-rock interaction(silicate and carbonate rocks dissolution,and dissolution of salt in sediments),carbonate sedimentation,sewage,agricultural fertilizer and manure,and nitrification are the main driving factors of the variation of hydrochemical components of Baiyangdian Lake across three hydrological *** findings suggest the need for effective control of substandard domestic sewage discharge,optimization of agricultural fertilization strategies,and proper management of animal manure to comprehensively improve the water environment in Baiyangdian Lake.

关键词： Hydrochemical variation Sources Human activities Water-rock interaction Multivariate statistical techniques

基于K_p=L_2D_2S_2矩阵分解的多变量自适应控制

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四川大学学报（自然科学版） 2010年第1期47卷 49-55页

作者：钟义长钟伦珑黄峰湖南工程学院应用技术学院湘潭411101 中国民航大学智能信号与图像处理天津市重点实验室天津300300

本文针对矩阵分解的多变量自适应控制,提出了具有噪声与未建模动态系统的鲁棒自适应控制问题.在高频增益矩阵分解的基础上,得到等价自适应控制律,通过重新定义虚拟规范化信号,对多变量的MRAC方案进行了理论分析,并证明了闭环系统的稳定... 详细信息

本文针对矩阵分解的多变量自适应控制,提出了具有噪声与未建模动态系统的鲁棒自适应控制问题.在高频增益矩阵分解的基础上,得到等价自适应控制律,通过重新定义虚拟规范化信号,对多变量的MRAC方案进行了理论分析,并证明了闭环系统的稳定性和收敛性.最后仿真验证了该方案是可行的.

关键词：多变量系统模型参考自适应控制高频增益矩阵 L2D2S2分解