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Bearing Fault Numerical Model for the Closed-slot Rotor Submersible Motor

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Chinese Journal of Electrical Engineering 2023年第2期9卷 84-93页

作者： Zhe Ke Bokai Guan Chong Di jingwen yan Xiaohua Bao School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China School of Electrical and Computer Engineering The Ohio State UniversityColumbus OH 43210USA

A numerical model of the bearing fault of a motor with a closed-slot rotor using the finite element method(FEM)is *** rotor’s radial motion can be regarded as static eccentric at the defect time points and healthy at other time *** frequency of the harmonic component is analyzed corresponding to bearing fault in stator current according to the radial movement of the motor ***,the relative permeability variation region is established to achieve the radial motion of the rotor with bearing ***,the relative permeability variation region is established in the health and static eccentric ***,the defect time points are estimated and the static eccentricity model by transient field is ***,the relative permeability of the variable region in the static eccentric model is imported into the variable region of the health model at the defect time *** simulation results show that the air gap flux density of the bearing fault model is different from that of the health model and static eccentric *** addition,the stator current contains harmonic components of the bearing *** analysis results prove the applicability of the proposed model.

关键词： Bearing fault finite element method relative permeability variation region closed-slot rotor stator current

A Design Method of the Rotor Auxiliary Slot for the Water-filled Submersible Induction Motors

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CES Transactions on Electrical Machines and Systems 2022年第1期6卷 37-45页

作者： Jiaxin Li jingwen yan Chong Di Xiaohua Bao Qinglong Zhu School of Electrical Engineering and Automation Hefei University of TechnologyHefei230009 China IEEE Hefei Hengda Jianghai Pump Co. LtdHefei230000 China

Aiming at the problem of electromagnetic vibration of the water-filled submersible induction motor(WSIM),a method of opening auxiliary slots on the rotor side is proposed to weaken the air-gap field harmonics caused by the rotor slot permeance *** analyzing the research status of electromagnetic vibration of the WSIM and the composition of the air-gap magnetic field of the motor,the idea that the auxiliary slots mainly affect the air-gap field harmonics by changing the air-gap permeance of the motor is put *** mathematical model of air-gap permeance of WSIM is established to simulate the influence of auxiliary slots on the air-gap *** the parametric analysis of the mathematical model,the change of auxiliary slot size is *** air-gap permeance waveform is decomposed by the two-dimensional Fourier transform,and then the variation of the air-gap permeance harmonics with the size of the auxiliary slot is ***,the finite element simulation model of the WSIM with the auxiliary slots is established,and the waveform of the air-gap flux density of the motor is analyzed to verify the effectiveness of the mathematical ***,the results show that after opening the auxiliary slot,the radial electromagnetic force of the motor was reduced by 28.4%.

关键词： Auxiliary slot the radial electromagnetic force the Water-filled Submersible Induction Motors

Current Status of the Application of Surgical Specialty Nursing Quality Evaluation Indicators

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Journal of Clinical and Nursing Research 2024年第8期8卷 75-82页

作者： Xiaohua Chen Xiaojuan Ling jingwen yan Sun Yat-sen Memorial Hospital Sun Yat-sen UniversityGuangzhou 510120Guangdong ProvinceChina

This paper reviews the current status of the application of surgical specialty nursing quality evaluation indicators both domestically and *** covers the related concepts,theoretical foundations,construction methods,construction fields,application research,and existing shortcomings of these *** suggests that scholars and researchers in the nursing field in China should base their work on mature theories,use scientific research methods,and construct a quality indicator system that aligns with China’s surgical development,is practical,unified,suitable for the local context,and beneficial for the development of the surgical nursing discipline.

关键词： Surgical specialty nursing Quality evaluation index Review

子女教育专项附加扣除对家庭教育支出的影响研究

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税务研究 2024年第10期 45-52页

作者：颜静雯中央财经大学创新发展学院

税收政策在提高居民可支配收入和促进家庭消费支出上具有重要作用。本文利用中国家庭追踪调查2014-2020年四期面板数据,结合子女教育专项附加扣除的申报条件,实证检验子女教育专项附加扣除对家庭教育支出是否具有积极影响,并以放开人口... 详细信息

税收政策在提高居民可支配收入和促进家庭消费支出上具有重要作用。本文利用中国家庭追踪调查2014-2020年四期面板数据,结合子女教育专项附加扣除的申报条件,实证检验子女教育专项附加扣除对家庭教育支出是否具有积极影响,并以放开人口生育政策构造工具变量进一步检验实证结果的稳健性。研究结果表明,家庭中受教育子女数量越多,政策实施后平均每个子女的课外辅导支出增加越多,且子女教育专项附加扣除对家庭教育支出的积极影响对于有高中受教育阶段子女的家庭更明显,对财务负责人为女性的家庭也更明显。本文的研究结果为提高子女教育专项附加扣除政策的精准性、细化扣除项目以改善家庭教育支出结构、优化扣除方式使得更多低收入者受益和加强税收宣传以扩大政策实施的积极效果提供了实证依据。

关键词：个人所得税专项附加扣除子女教育家庭教育支出

The　Spectrum　of　the　Square　of　a　Synchronous　Random　Pulse　Train　in　Impulse　Noise　Environments

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The Journal of China Universities of Posts and Telecommunications 1996年第2期3卷 78-80页

作者： yan jingwen Qi Lei and Yue Zhengui(Department of Radio Communication, Changchun Posts and Telecommunications institute, Changchun 130012, R. P. China)

New forms are derived relatively simply for the spectrum of the square of synchronous randompulse train of the form , that was contaminated by impulse noise, and whose coefficient Ci areindependent, zero-mean, unit-variance random and g(t) is a given deterlninistic pulse shape. This pulsetrain's power spectrum is derived. Its discrete part can be used to synchronize carrier, and its continuouspart limits the sighal to noise ratio available in any given bandwidth irc in the spectral lines.

关键词： s: power spectrum impulse noise gaussian process correlation function fourier transform

同步辐射红外光谱研究结肠癌细胞的软X射线辐射效应

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核技术 2012年第4期35卷 260-264页

作者：闫婧雯陈亮蒋诗平中国科学技术大学国家同步辐射实验室合肥230029

为探索红外光谱技术在辐射效应研究中的应用,以合肥同步辐射红外和远红外光谱实验站为平台开展软X射线低剂量辐射效应研究。用傅里叶变换红外显微镜光谱仪采集软X射线辐照前后的结肠癌细胞(HCT116)的单细胞光谱,分析光谱的位置和强度等... 详细信息

为探索红外光谱技术在辐射效应研究中的应用,以合肥同步辐射红外和远红外光谱实验站为平台开展软X射线低剂量辐射效应研究。用傅里叶变换红外显微镜光谱仪采集软X射线辐照前后的结肠癌细胞(HCT116)的单细胞光谱,分析光谱的位置和强度等变化。发现辐照后癌细胞吸收谱在峰的强度、位置都有明显变化,尤其位于1079 cm^(-1)、1236 cm^(-1)的核酸骨架磷脂对称和反对称振动吸收有明显的差异。研究表明:辐射诱导的癌细胞生物效应可以通过单细胞红外光谱灵敏表征;该方法有可能成为快速检测辐射效应的有效手段。

关键词：同步辐射软X射线傅里叶变换单细胞红外光谱结肠癌细胞

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基于双稀疏优化的空域错误隐藏

计算机工程 2019年第2期45卷 245-249页

作者：严静文肖晶高戈武汉大学国家多媒体软件工程技术研究中心武汉430072 武汉大学计算机学院武汉430072

现有空域错误隐藏算法通常利用线性插值或者常规稀疏表达恢复丢失像素,但线性插值在恢复不平滑图像时因邻域信息不一致导致恢复图像模糊,而常规稀疏表达因字典构建不当造成丢失像素重建效果较差。为此,提出一种改进的空域错误隐藏算法,... 详细信息

现有空域错误隐藏算法通常利用线性插值或者常规稀疏表达恢复丢失像素,但线性插值在恢复不平滑图像时因邻域信息不一致导致恢复图像模糊,而常规稀疏表达因字典构建不当造成丢失像素重建效果较差。为此,提出一种改进的空域错误隐藏算法,采用动态阈值搜索潜在集合和模板集合提高字典构建精度,利用典型相关分析获得双稀疏优化的初值,通过稀疏重建恢复丢失像素。实验结果表明,与现有主流算法相比,该算法的峰值信噪比至少提高1. 23 dB,具有较好的错误隐藏效果。

关键词：空域错误隐藏线性插值 I帧丢失字典构建稀疏优化

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人脸识别:从二维到三维

计算机工程与应用 2011年第11期47卷 155-159页

作者：蔡泽民闫敬文汕头大学工学院电子工程系广东汕头515063

人脸识别是生物特征识别技术的一个重要方向。虽然目前大部分研究都还只是针对二维人脸图像,但是3D人脸模型包含更丰富的人脸信息,有助于机器对人脸的识别。从二维到三维,人脸识别研究进入了一个新的阶段。从3D人脸数据的获取方式入手,... 详细信息

人脸识别是生物特征识别技术的一个重要方向。虽然目前大部分研究都还只是针对二维人脸图像,但是3D人脸模型包含更丰富的人脸信息,有助于机器对人脸的识别。从二维到三维,人脸识别研究进入了一个新的阶段。从3D人脸数据的获取方式入手,介绍最近提出的一系列3D人脸识别算法,并进行归类。最后提出"有针对性地获取3D人脸模型数据是进行有效识别的基础"这一结论。

关键词： 3D人脸识别 3D人脸数据通用模型

Iterative learning control based ramp metering tracking iteration-varying trajectories with internal model

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Iterative learning control based ramp metering tracking iter...