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An Envelope Algorithm for Single Nanoparticle Collision Electrochemistry

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Chinese Journal of Chemistry 2021年第7期39卷 1936-1940页

作者： chun-yu xu Ru-Jia yu xue Ni Su-Wen xu Xi-Xin Fu Yong-Jing Wan Yi-Lun Ying Yi-Tao Long School of Information Science and Engineering East China University of Science and TechnologyShanghai200237 China State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjingJiangsu210023 China Chemistry and Biomedicine Innovation Center Nanjing UniversityNanjingJiangsu210023 China Department of Chemistry East China University of Science and TechnologyShanghai200237 China

Main observation and conclusion Single nanoparticle collision has attracted great attention in the last several years to reveal the electron transfer and motion trajectories of individual particles at the electrode **... 详细信息

关键词： Analytical methods Electrochemistry Nanopartlcles Savitzky-Golay filter Single nanoparticle collision

Complete Convergence of Weighted Sums for Arrays of Rowwise m-negatively Associated Random Variables

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Communications in Mathematical Research 2014年第1期30卷 41-50页

作者： GUO MING-LE xu chun-yu ZHU DONG-JIN School of Mathematics and Computer Science Anhui Normal University

In this paper, we discuss the complete convergence of weighted sums for arrays of rowwise m-negatively associated random variables. By applying moment inequality and truncation methods, the sufficient conditions of complete convergence of weighted sums for arrays of rowwise m-negatively associated random variables are established. These results generalize and complement some known conclusions.

关键词： complete convergence negatively associated m-negatively associated,weighted sum

Blood collection procedures influence contamination rates in blood culture： a prospective study

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Chinese Medical Journal 2011年第23期124卷 4002-4006页

作者： GE Ying LIU Xiao-qing xu Ying-chun xu Shan yu Min-hong ZHANG Wei DENG Guo-hua Department of Infectious Diseases Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730 China

Background Blood culture contamination is a significant adverse event. The aim of this project was to evaluate the efficacy of a strict blood collection procedure in reducing the blood culture contamination rate. Methods A prospectively controlled study was performed in two different medical areas in Peking Union Medical College Hospital （PUMCH） for 16 months （from May 2006 to September 2007）. In test group, a strict blood collection procedure was carried out by trained nurses with the veinpuncture sites were scrupulously disinfected with 2.5% tincture of iodine plus 70% alcohol. In control group, commonly used procedure in PUMCH was performed with 0.45% chlorhexidine acetate plus 0.2% iodine. Blood culture positive results for 4 target organisms （Coagulase-negafive staphylococci, Propionibacterium acnes, physicians from infectious department to （contamination）. Corynebacterium species and Bacillus determine whether a sample was true species） were further assessed by positive （pathogen） or false positive Results Total 9321 blood culture collections were analyzed. The blood culture contamination rate in test group was significantly lower than that in control group （5/3177 （0.16%） vs. 77/6144 （1.25%）; x2=13.382, P 〈0.001）. The most common contaminant was Coagulase-negative staphylococcus （76.83%）. The average cultural time during which contaminated samples became positive was longer than that for true pathogen samples （42.0 hours vs. 13.9 hours, P=-0.041）. Conclusion Using a strict blood collection procedure can significantly reduce blood culture contamination rate.

关键词： blood culture contamination rate disinfection blood collection procedure

Prevalence and Treatment of Children＇s Asthma in Rura Areas Compared with Urban Areas in Beijing

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Chinese Medical Journal 2015年第17期128卷 2273-2277页

作者： Wen-Jing Zhu Hai-Xia Ma Hui-Ying Cui xu Lu Ming-Jun Shao Shuo Li Yan-Qing Luo Qiang Wang chun-yu xu Dong-Qun xu Chuan-He Liu yu-Zhi Chen Center for Asthma Prevention and Education Capital Institute of Pediatrics Beijing 100020 China Department of Pediatrics Liangxiang Hospital Fangshan District Beijing 102401 China Department of Pediatrics Tongzhou Maternal and Child Health Hospital Beijing 101199 China Institute of Environmental Health and Related Product Safety Chinese Center for Disease Control and Prevention Beijing 100021 China

The prevalence of childhood asthma has been increasing in China. This study aimed to compare the prevalence, diagnosis, and treatment of asthmatic children from urban and rural areas in Beijing, China. Methods： Schools, communities, and kindergartens were randomly selected by cluster random sampling from urban and rural areas in Beijing. Parents were surveyed by the same screening questionnaires. On-the-spot inquiries, physical examinations, medical records, and previous test results were used to diagnose asthmatic children. Information on previous diagnoses, treatments, and control of symptoms was obtained. Results： From 7209 children in rural areas and 13,513 children in urban areas who completed screening questionnaires, 587 children were diagnosed as asthma. The prevalence of asthma in rural areas was lower than in urban areas （1.25% vs. 3.68%, χ^2 = 100.80, P 〈 0.001）. The diagnosis of asthma in rural areas was lower than in urban areas （48.9% vs. 73.9%, χ^2 = 34.6, P 〈 0.001）. Compared with urban asthmatic children （56.5%）, only 35.6% of rural asthmatic children received inhaled corticosteroids （P 〈 0.05）. The use ofbronchodilators was also lower in rural areas than in urban areas （56.5% vs. 66.4%, χ^2 = 14.2, P 〈 0.01）. Conclusion： The prevalence of asthma in children was lower in rural areas compared with children in the urban area of Bcijing. A considerable number of children were not diagnosed and inadequately treated in rural areas,

关键词： Asthma Children Diagnosis Treatment Rural Urban

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预测电流闭环控制方法的研究

电气传动 2013年第12期43卷 37-40页

作者：许春雨周娟太原理工大学煤矿装备与安全控制山西省重点实验室山西太原030024

研究空间矢量无差拍电流控制方法并将其应用于有源电力滤波器。为了提高指令电流预测的准确性,将预测电流的开环控制改进为闭环控制,并利用Matlab软件对比研究了线性预测算法与抛物线预测算法,从而选择采用抛物线预测法进行基于DSP的有... 详细信息

研究空间矢量无差拍电流控制方法并将其应用于有源电力滤波器。为了提高指令电流预测的准确性,将预测电流的开环控制改进为闭环控制,并利用Matlab软件对比研究了线性预测算法与抛物线预测算法,从而选择采用抛物线预测法进行基于DSP的有源电力滤波器实验。实验结果证明了该控制方法的可行性与有效性,使有源电力滤波器能很好地抑制主要次谐波。

关键词：电流闭环控制空间矢量无差拍控制抛物线预测

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阴影遮蔽条件下光伏发电效率的增大方法

水电能源科学 2015年第11期33卷 207-210,201页

作者：彭玥许春雨太原理工大学煤矿电气设备与智能控制山西省重点实验室山西太原030024

受阴影遮蔽影响,光伏阵列输出功率下降,功率曲线呈现多峰值,使传统的最大功率点(MPPT)算法失效陷入局部极值点。基于光伏电池的等效电路模型,在正常和有阴影遮蔽情况下对光伏组件串并联输出特性进行仿真,分析功率曲线上局部极值点的产... 详细信息

受阴影遮蔽影响,光伏阵列输出功率下降,功率曲线呈现多峰值,使传统的最大功率点(MPPT)算法失效陷入局部极值点。基于光伏电池的等效电路模型,在正常和有阴影遮蔽情况下对光伏组件串并联输出特性进行仿真,分析功率曲线上局部极值点的产生原因及变化规律。针对阴影遮蔽对光伏发电效率的影响,提出建立微型光伏发电系统,采用光伏组件间解耦的方法,跟踪每个光伏组件的最大功率点,使光伏发电效率达到最优。试验结果验证了该方法的可行性,为今后光伏电站的建设提供了指导。

关键词：阴影遮蔽最大功率点微型光伏发电系统光伏电站

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三电平逆变器中点电位平衡控制的研究

电气传动 2013年第2期43卷 40-43页

作者：许春雨刘梅太原理工大学电气与动力工程学院山西太原030024

中点电位不平衡是二极管钳位型三电平逆变器的固有问题,分析了造成三电平逆变器中点电位不平衡的原因,研究了注入零序分量实现中点电位平衡控制的SPWM方法,并且引入反馈结构加以改进。研究表明:在一个基波周期,注入6n倍次零序分量能够... 详细信息

中点电位不平衡是二极管钳位型三电平逆变器的固有问题,分析了造成三电平逆变器中点电位不平衡的原因,研究了注入零序分量实现中点电位平衡控制的SPWM方法,并且引入反馈结构加以改进。研究表明:在一个基波周期,注入6n倍次零序分量能够产生控制中点电位所需的中点电流直流分量,中点电位也得到了有效的控制。仿真结果验证了该控制方法的有效性。

关键词：三电平逆变器中点平衡控制零序电压

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基于初始位置的高速公路快速地图匹配算法

中国惯性技术学报 2017年第4期25卷 461-465,472页

作者：滕志军曲兆强何义昌佟育春徐春雨张丽伟东北电力大学信息工程学院吉林132012 国网吉林供电公司信息通信分公司吉林132000

针对车辆行驶在高速公路过程中,传统地图匹配算法存在大量冗余检索时间,且消除垂直误差后仍存在水平误差等问题,设计了一种基于初始定位信息的快速地图匹配算法。该算法首先利用初始定位点到候选路段的距离与夹角确定车辆所行驶道路,然... 详细信息

针对车辆行驶在高速公路过程中,传统地图匹配算法存在大量冗余检索时间,且消除垂直误差后仍存在水平误差等问题,设计了一种基于初始定位信息的快速地图匹配算法。该算法首先利用初始定位点到候选路段的距离与夹角确定车辆所行驶道路,然后考虑道路网拓扑结构和连通性,将后续定位点直接投影到初始确定的道路上,减少检索道路的时间;同时为提高算法的精确度,在引用初始定位信息时,通过设置距离阈值剔除定位数据漂移点,并利用一元线性方程建立HP模型以消除水平误差。经理论计算和实际测试表明,该算法利用初始获得的7个连续定位点,能准确检索出车辆正在行驶的道路,节省36%的检索时间,借助HP模型可以减少定位点与车辆实际位置之间45%的投影误差。因此,与连续匹配算法和垂直投影方式相比,该算法具有检索过程简单、检索准确率高、误差消除大的优势。

关键词：高速公路初始信息地图匹配距离阈值水平误差

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