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Effect of Barrier Materials on Discharge Properties in Air at Low Pressure

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高电压技术 2007年第12期33卷 80-84页

作者： liMing li cheng-rong ZHAN Hua-mao XU Jin-bao ZHANG Xian-jun Beijing Key Laboratory of High Voltage ~ EMC School of Electric and Electronic Engineering North China Electric Power University Beijing 102206 China

Dielectric barrier discharge(DBD) is widely investigated in order to obtain uniform low-temperature *** studies have proved that some barrier materials,especially electrets,can improve the uniformity of *** is regarded as an available way to get atmospheric pressure glow discharge(APGD).In this paper,discharge forms with 4 different barrier materials(alumina,quartz,PTFE and PET) are investigated,and the transition of discharge form depending on the air pressure are recorded to estimate the influence of barrier materials on *** using electrets as barrier materials,homogeneous discharges can be obtained in a more wide pressure *** the same experimental conditions,discharges with electrets are more uniform or have larger uniform areas due to the storage and desorption of charges on the surface of *** electrons deposited in the surface layer can be released on next half cycle when the polarity of the applied voltage changes,and provide a number of seed electrons,which makes the discharge more *** capacitance and the permittivity of barrier materials have no effect on the discharge form directly.

关键词：放电特性低气压电子跃迁电介体表面电荷栅栏

Kinematics Analysis Based on Screw Theory of a Humanoid Robot

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Journal of China University of Mining and Technology 2007年第1期17卷 49-52页

作者： MAN Cui-hua FAN Xun li cheng-rong ZHAO Zhong-hui School of Mechanical Electronic and Information Engineering China University of Mining ＆ Technology Beijing 100083 China Institute of Automation Chinese Academy of Sciences Beijing 100080 China

A humanoid robot is a complex dynamic system for its idiosyncrasy. This paper aims to provide a mathematical and theoretical foundation for the design of the configuration, kinematics analysis of a novel humanoid robot. It has a simplified configuration and design for entertainment purpose. The design methods, principle and mechanism are discussed. According to the design goals of this research, there are ten degrees of freedom in the two bionic arms. Modularization, concurrent design and extension theory methods were adopted in the configuration study and screw theory was introduced into the analysis of humanoid robot kinematics. Comparisons with other methods show that: 1) only two coordinates need to be established in the kinematics analysis of humanoid robot based on screw theory; 2) the spatial manipulator Jacobian obtained by using twist and exponential product formula is succinct and legible; 3) adopting screw theory to resolve the humanoid robot arms kinematics question can avoid singularities; 4) using screw theory can solve the question of specification insufficiency.

关键词： bionics arm screw theory extension theory Jacobian matrix modularization design

Estimation Study of New Cancer Cases and Deaths in Wuwei, Hexi Corridor Region, China, 2018

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Biomedical and Environmental Sciences 2017年第11期30卷 829-833页

作者： CAO Bo Yu li cheng Yun XU Feng Lan liU Xiao Qin YANG Yan Xu li Jing GAO Cai Yun rong You Ming li rong cheng li Ya li ZHENG Shan BAI Ya Na YE Yan cheng Institute of Epidemiology and Statistics School of Public Health Center for Cancer Prevent and Treatment Lanzhou University Department of Cancer Epidemiology Wuwei Cancer Registry Gansu Wuwei Tumor Hospital

Population-based cancer registration data were collected to estimate the cancer incidence and mortality in Wuwei, Hexi Corridor Region, China in 2018. We used the 2011-2013 data to predict the number of new cases and deaths in 2018 and the 2003-2013 data to analyze trends in cancer incidence and mortality. The goal is to enable cancer prevention and control directions. Our results indicated that stomach cancer is the most common cancer. For all cancers combined, the incidence and mortality rates showed significantly increasing trends（＋2.63% per year; P 〈 0.05 and ＋1.9% per year; P 〈 0.05）. This study revealed a significant cancer burden among the population of this area. Cancer screening and prevention should be performed after an epidemiological study of the cause of the cancer is completed.

关键词： Estimation Study of New Cancer Hexi Corridor Region

发电机局部放电脉冲沿定子绕组传播规律的研究

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电网技术 2005年第8期29卷 65-70页

作者：程养春李成榕王伟华北电力大学高电压与电磁兼容北京市重点实验室北京市昌平区102206 华北电力大学电力系统保护与动态安全监控教育部重点实验室北京市昌平区102206

为研究发电机内部局部放电脉冲的传播规律,根据一实际50MW汽轮发电机定子绕组对方波、脉冲波和正弦波试验信号的响应结果,研究了2MHz以下频段试验脉冲沿定子线棒的传输线传播规律及信号幅值的变化规律、信号传播时延等;分析了2～6MHz和7... 详细信息

为研究发电机内部局部放电脉冲的传播规律,根据一实际50MW汽轮发电机定子绕组对方波、脉冲波和正弦波试验信号的响应结果,研究了2MHz以下频段试验脉冲沿定子线棒的传输线传播规律及信号幅值的变化规律、信号传播时延等;分析了2～6MHz和7～12MHz频段下试验脉冲沿定子绕组端部圆周传播的电容耦合机理及信号幅值的变化规律.发现了试验脉冲在三相绕组之间存在相互耦合的现象;2～6MHz频段下试验脉冲沿定子绕组端部圆周传播时幅值基本不发生衰减.这些研究结果将有助于理解局部放电信号在定子绕组中的传播规律,可为确定局部放电源所属相别甚至位置提供参考信息.

关键词：汽轮发电机定子绕组局部放电脉冲传播数字示波器

局部放电检测中傅立叶级数法与几种抗干扰方法的比较分析

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电网技术 2005年第12期29卷 33-38页

作者：程养春李成榕王伟高电压与电磁兼容北京市重点实验室(华北电力大学) 北京市昌平区102206 电力系统保护与动态安全监控教育部重点实验室(华北电力大学) 北京市昌平区102206

提出了一种新的抗窄带干扰方法,傅立叶级数法。首先利用原始局放数据估算窄带干扰的频率和傅立叶级数的系数,然后利用傅立叶系数估算窄带干扰波形,再将原始数据与估算结果相减,则窄带干扰被抵消而局放脉冲得以保留。文章利用仿真数据和... 详细信息

提出了一种新的抗窄带干扰方法,傅立叶级数法。首先利用原始局放数据估算窄带干扰的频率和傅立叶级数的系数,然后利用傅立叶系数估算窄带干扰波形,再将原始数据与估算结果相减,则窄带干扰被抵消而局放脉冲得以保留。文章利用仿真数据和现场试验数据分析了该方法的抗干扰效果,并与常用的数字滤波器、时频转换法、自适应滤波和小波滤波等方法进行了比较。发现该方法能够较好地消除窄带干扰,同时尽量保留了局放脉冲的幅值和极性特征。特别是在脉冲的主要频谱与窄带干扰的频谱非常接近时,傅立叶级数法的抗窄带干扰效果更明显。

关键词：高压电力设备绝缘状况局部放电检测傅立叶级数法抗干扰方法

用傅立叶级数法消除局部放电检测中窄带干扰的研究

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中国电机工程学报 2005年第20期25卷 106-111页

作者：程养春李成榕王伟华北电力大学电气工程学院北京市昌平区102206 高电压与电磁兼容北京市重点实验室北京市昌平区102206 电力系统保护与动态安全监控教育部重点实验室(华北电力大学) 北京市昌平区102206

提出了一种新的抗窄带干扰方法——傅立叶级数法,利用原始数据通过傅立叶级数估计原始数据中的窄带干扰波形,然后与原始数据相减,以得到局部放电脉冲信号;通过仿真数据和现场实际数据验证了该方法的抗干扰效果,发现该方法能够在完全消... 详细信息

提出了一种新的抗窄带干扰方法——傅立叶级数法,利用原始数据通过傅立叶级数估计原始数据中的窄带干扰波形,然后与原始数据相减,以得到局部放电脉冲信号;通过仿真数据和现场实际数据验证了该方法的抗干扰效果,发现该方法能够在完全消除窄带干扰的同时,基本保留局部放电脉冲的波形、幅值和极性,尤其在脉冲信号的中心频谱与干扰的频谱非常接近时;讨论了随机干扰、频率误差和模数转换量化误差对抗干扰效果的影响,认为这些因素对抗干扰效果的影响不大;与常见的时频转换法和自适应滤波法进行了对比分析,结果表明傅立叶级数法在保持局部放电原始波形、幅值和极性信息方面具有明显优点。

关键词：局部放电窄带干扰傅立叶级数电力设备

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自身炎症性疾病

中华儿科杂志 2008年第11期46卷 842-847页

作者：李成荣深圳市儿童医院儿科研究所 518026

自身炎症性疾病（autoinflammatory disorder）是一组遗传性炎症疾病，以发热、皮疹、关节痛、关节炎、眼部病变为突出症状。以往本病曾称为遗传性周期热综合征，如家族性地中海热（FMF）、高IgD伴周期热综合征（HIDS）、肿瘤坏死因子... 详细信息

自身炎症性疾病（autoinflammatory disorder）是一组遗传性炎症疾病，以发热、皮疹、关节痛、关节炎、眼部病变为突出症状。以往本病曾称为遗传性周期热综合征，如家族性地中海热（FMF）、高IgD伴周期热综合征（HIDS）、肿瘤坏死因子受体相关周期热综合征（TRAPS）等。近年发现某些炎症反应信号途径传导、调控因子基因突变可扰乱天然免疫，导致炎症反应，

关键词：炎症性疾病自身遗传性周期热肿瘤坏死因子受体家族性地中海热炎症反应综合征炎症疾病

Long term effectiveness of infancy low-dose hepatitis B vaccine immunization in Zhuang minority area in China

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World Journal of Gastroenterology 1999年第2期5卷 34-36页

作者： li Hui 1, li rong cheng 2, liAO Su Su 1, GONG Jian 2, ZENG Xian Jia 1 and li Yan Ping 2

AIM To observe the long-term effectiveness of low-dose immunization strategy and risk factors of HBsAg carriers in immunized children of Zhuang minorities of Longan County in the 9th year after infancy *** Two epidemiologic methods, a cross-sectional follow-up study and a case-control study, were used for the evaluation of the serological effect and the determination of the risk factors. Hepatitis B virus markers were detected with *** The protective anti-HBs-positive rate was 43.8% in 1183 children aged 1-9 years, who were immunized with three doses of 10 μg hepatitis B vaccine in infancy according to 0, 1 and 6 months schedule. It declined from 87.9% in the first year to 37.1% in the 9th year after vaccination. The HBsAg-positive rate was 1.6%, not increasing with age during 9 years after the infant immunization program. Compared with 14.0% of HBsAg-positive rate of the baseline survey in 1985, the effectiveness of hepatitis B vaccine immunization was 88.6%. Of 36 immunized children with positive HBsAg, 89.1% were likely attributable to HBsAg positivity of their *** The long-term effectiveness of infancy low-dose hepatitis B vaccine immunization is high, and the booster is not needed 9 years after the vaccination in the Zhuang minority area where hepatitis B is highly endemic. A high-dose immunization strategy should be recommended in order to further decrease the current HBsAg-positive rate.

关键词： hepatitis B vaccine immunization HBsAg risk factor

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遗传与儿童免疫性疾病

中华儿科杂志 2006年第6期44卷 425-427页

作者：李成荣深圳市儿童医院儿科研究所分子免疫室 518026

根据遗传因素在发病机制中的作用可将疾病分为单基因遗传病和复杂性状(complex traits)疾病.常见的原发性免疫缺陷病多属单基因遗传病,遵循孟德尔遗传规律,其遗传方式可分为常染色体显性遗传(AD)、常染色体隐性遗传(AR)、X连锁遗传(XL)... 详细信息

根据遗传因素在发病机制中的作用可将疾病分为单基因遗传病和复杂性状(complex traits)疾病.常见的原发性免疫缺陷病多属单基因遗传病,遵循孟德尔遗传规律,其遗传方式可分为常染色体显性遗传(AD)、常染色体隐性遗传(AR)、X连锁遗传(XL)等.多数自身免疫性疾病[如系统性红斑狼疮(SLE)、类风湿性关节炎(JRA)、川崎病(KD)]和过敏性疾病属复杂性状疾病;它们是由许多相关基因加和作用形成的.复杂性状性疾病目前已成为生命科学中普遍关注的前沿,阐明复杂性状疾病的发病机制,需要解决两个问题:一是明确疾病的主要易感基因,这需要在人类基因组中找寻一种数目多、分布广泛且相对稳定的遗传标记,单核苷酸多态性(SNPs)正是代表了这样的一种标记;二是寻找影响这些基因表达的表观遗传(epigenetic)修饰因子(如DNA甲基化).因此,本文仅在简单介绍一般免疫性疾病遗传学特点的基础上,结合目前的临床基础研究资料,重点讨论表观遗传修饰及SNPs与免疫系统疾病的关系。[第一段]

关键词：自身免疫性疾病单基因遗传病复杂性状疾病原发性免疫缺陷病常染色体显性遗传常染色体隐性遗传表观遗传修饰孟德尔遗传规律系统性红斑狼疮类风湿性关节炎