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Calculating magnetic shielding effectiveness for high-power dc comparator by magnetic circuit method

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Journal of Chongqing University 2007年第2期6卷 113-118页

作者： WANG Xiao-wei ren shi-yan School of Electrical and Electronics Engineering Huazhong University of Science ＆ Technology Wuhan 430074 P.R. China

Magnetic shielding is very important in the design of a high-power dc comparator. This paper addressed the application of magnetic circuit method to calculate the magnetic shielding effectiveness of high-power dc comparators when an external radial magnetic field is added. The mathematical relationship between the magnetic shielding effectiveness and the parameters of the magnetic shielding body were obtained. To verify the validity of the calculation method, we developped a procedure to measure the magnetic shielding effectiveness of the magnetic body by measuring the induction voltage of the detection winding instead of the magnetic intensity at a point in the magnetic shielding body, making the manipulation much easier. The result calculated with the magnetic circuit method turns out to be closer to the measured one compared with that calculated with a conventional algorithm proposed by ren, suggesting that the magnetic circuit method is an applicable tool for estimating the toroidal cavity magnetic shielding effectiveness of a heavy current comparator when a radial magnetic field is added.

关键词： radial magnetic field magnetic shielding effectiveness magnetic circuit analysis method magnetic potential

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直流传感器回馈补偿系统的设计

高电压技术 2007年第7期33卷 63-66页

作者：王晓蔚任士焱华中科技大学电气与电子工程学院武汉430074

在磁势自平衡回馈补偿式直流传感器中,一次被测电流磁势绝大部分已被电抗器直接由交流电源提供的电流自动平衡掉,剩余磁势由直流传感器的回馈补偿系统补偿。直流传感器的差值电流回馈补偿电路利用双向铁心磁放大器的基本原理,在电抗器... 详细信息

在磁势自平衡回馈补偿式直流传感器中,一次被测电流磁势绝大部分已被电抗器直接由交流电源提供的电流自动平衡掉,剩余磁势由直流传感器的回馈补偿系统补偿。直流传感器的差值电流回馈补偿电路利用双向铁心磁放大器的基本原理,在电抗器铁心的空腔内设置零安匝检测铁心和线圈以检测该半周期内直流磁势平衡的安匝差,用于自动跟踪补偿,是一个具有反馈特性的闭环系统。差值补偿电流输出与磁势自平衡电流输出的和即为被测直流电流。为了分析控制系统的稳定性,用方块图来表示控制系统的组成。差值电流回馈补偿系统是一个典型的闭环系统。应用劳斯及古尔维茨稳定判据,通过特征方程的根与各项系数的关系来判别系统的特征根是否全部具有负实部,从而分析线性系统的稳定性。

关键词：磁势自平衡回馈补偿 PID控制劳斯判据传递函数稳定性

Optimized Axillary Vein Technique versus Subclavian Vein Technique in Cardiovascular Implantable Electronic Device Implantation： A Randomized Controlled Study

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Chinese Medical Journal 2016年第22期129卷 2647-2651页

作者： Peng Liu Yi-Feng Zhou Peng yang yan-Sha Gao Gui-Ru Zhao shi-yan ren Xian-Lun Li Department of Cardiology China-Japan Friendship Hospital Beijing 100029 China

Background：The conventional venous access for cardiovascular implantable electronic device （CIED） is the subclavian vein,which is often accompanied by high complication *** aim of this study was to assess the efficacy and safety of optimized axillary vein ***：A total of 247 patients undergoing CIED implantation were included and assigned to the axillary vein group or the subclavian vein group *** rate of puncture and complications in the perioperative period and follow-ups were ***：The overall success rate （95.7% vs.96.0%） and one-time success rate （68.4% vs.66.1%） of punctures were similar between the two *** the subclavian vein group,pneumothorax occurred in three *** subclavian gaps of three patients were too tight to allow operation of the electrode *** contrast,there were no puncture-associated complications in the axillary vein *** the patient follow-ups,two patients in the subclavian vein group had subclavian crush syndrome and both of them received lead *** incidence of complications during the perioperative period and follow-ups of the axillary vein group and the subclavian vein group was 1.6% （2/125） and 8.2% （10/122）,respectively （χ^2=5.813,P =0.016）.Conclusion：Optimized axillary vein technique may be superior to the conventional subclavian vein technique for CIED lead placement.

关键词： Axillary Vein Cardiovascular Implantable Electronic Device Randomized Controlled Trial Subclavian Vein

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水动力条件分析在海洋工程勘察中的应用

中国造船 2005年第B11期46卷 126-136页

作者：任世焱中海油田服务股份有限公司油田技术事业部勘察服务中心天津300452

动力地质灾害是我国目前造成工程地质灾害的重大影响因素之一。解决动力地质灾害影响的首要问题是认识动力地质灾害。作者在生产实践中总结出一套行之有效的动力地质灾害解释方法。本文以平湖油气田海底管线岱山段新路由调查为案例，应... 详细信息

动力地质灾害是我国目前造成工程地质灾害的重大影响因素之一。解决动力地质灾害影响的首要问题是认识动力地质灾害。作者在生产实践中总结出一套行之有效的动力地质灾害解释方法。本文以平湖油气田海底管线岱山段新路由调查为案例，应用水动力观、动力地质灾害概念及水动力地质灾害解释方法进行资料解释，更深刻地剖析了平湖油气田海底管线岱山段新路由环境，为平湖油气田海底管线岱山段新路由管理者提出了具有针对性的建议。

关键词：水动力海洋工程勘察应用

维普期刊数据库评论

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维普期刊数据库

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磁势自平衡回馈补偿式直流传感器难点研究

电测与仪表 2006年第10期43卷 4-7页

作者：褚江任士焱华中科技大学电气与电子工程学院电测教研室武汉430074

磁势自平衡回馈补偿式直流传感理论是在电抗器磁势自平衡原理与差值电流回馈补偿原理的基础上,将两者相结合而形成的一种新的传感原理与方法。为了实现基于该原理的传感器,本文首先对磁势自平衡回馈补偿式直流传感器模拟样机的工作过程... 详细信息

磁势自平衡回馈补偿式直流传感理论是在电抗器磁势自平衡原理与差值电流回馈补偿原理的基础上,将两者相结合而形成的一种新的传感原理与方法。为了实现基于该原理的传感器,本文首先对磁势自平衡回馈补偿式直流传感器模拟样机的工作过程进行简要介绍,重点研究分析了模拟样机线路中纹波感应干扰信号的影响及其传感器输出信号误差处理的问题。模拟样机的大量实验验证了磁势自平衡回馈补偿式直流传感理论正确性的同时,又暴露了模拟样机设计的局限性。被测直流磁势在1500～9000A T内时,通过简单的线性化处理可使模拟样机的输出误差控制在0.1%左右。

关键词：磁势平衡回馈补偿感应干扰线性化

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一种实用的串并联混合有源电力滤波器

电网技术 2007年第21期31卷 32-36页

作者：杨华云任士焱华中科技大学电气与电子工程学院湖北省武汉市430074

设计了一种实用的串并联混合有源电力滤波器,分析了其结构、工作原理和滤波性能。在该滤波器中,串联在系统和谐波负载之间的零磁通变流器可自动对基波呈低阻抗、对谐波呈高阻抗,从而实时检测出剩余谐波电流流过变流器时产生的谐波电压... 详细信息

设计了一种实用的串并联混合有源电力滤波器,分析了其结构、工作原理和滤波性能。在该滤波器中,串联在系统和谐波负载之间的零磁通变流器可自动对基波呈低阻抗、对谐波呈高阻抗,从而实时检测出剩余谐波电流流过变流器时产生的谐波电压降、实现滤波;逆变器可产生一个与检测到的谐波电压成正比的电压。通过将耦合变压器与无源电力滤波器串联后并入电网,减少了流入系统的谐波电流。实验结果验证了该滤波器设计原理的正确性,表明其能有效降低滤波器有源部分的容量,具有良好的滤波性能。

关键词：混合有源电力滤波器零磁通变流器谐波抑制无源电力滤波器

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商业经济与人才资源配置

商业经济与人才资源配置

T cell interactions with microglia in immune-inflammatory processes of ischemic stroke

1988年

作者：上海市人事局研究室上海市科技干部局研究室

来源：南通市图书馆图书评论

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Neural Regeneration Research 2025年第5期20卷 1277-1292页

作者： Yuxiao Zheng Zilin ren Ying Liu Juntang yan Congai Chen yanhui He Yuyu shi Fafeng Cheng Qingguo Wang Changxiang Li Xueqian Wang School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijingChina Library Beijing University of Chinese MedicineBeijingChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue *** the first immune cells to be activated after an ischemic stroke,microglia play an important immunomodulatory role in the progression of the *** an ischemic stroke,peripheral blood immune cells(mainly T cells)are recruited to the central nervous system by chemokines secreted by immune cells in the brain,where they interact with central nervous system cells(mainly microglia)to trigger a secondary neuroimmune *** review summarizes the interactions between T cells and microglia in the immune-inflammatory processes of ischemic *** found that,during ischemic stroke,T cells and microglia demonstrate a more pronounced synergistic ***1,Th17,and M1 microglia can co-secrete proinflammatory factors,such as interferon-γ,tumor necrosis factor-α,and interleukin-1β,to promote neuroinflammation and exacerbate brain ***2,Treg,and M2 microglia jointly secrete anti-inflammatory factors,such as interleukin-4,interleukin-10,and transforming growth factor-β,to inhibit the progression of neuroinflammation,as well as growth factors such as brain-derived neurotrophic factor to promote nerve regeneration and repair brain *** interactions between microglia and T cells influence the direction of the subsequent neuroinflammation,which in turn determines the prognosis of ischemic stroke *** trials have been conducted on the ways to modulate the interactions between T cells and microglia toward anti-inflammatory communication using the immunosuppressant fingolimod or overdosing with Treg cells to promote neural tissue repair and reduce the damage caused by ischemic ***,such studies have been relatively infrequent,and clinical experience is still *** summary,in ischemic stroke,T cell subsets and activated micro

关键词： brain immune inflammation interaction ischemic stroke mechanism microglia neuron secondary injury T cells

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磁屏蔽效能的有限元分析

计量学报 2006年第4期27卷 376-379页

作者：王晓蔚任士焱杨华云吴波华中科技大学电气与电子工程学院湖北武汉430074

提出了磁屏蔽效能问题的三维有限元模型的建立方法,应用ANSYS软件得到磁屏蔽效能为28.78,并将结果绘制成曲线,使结果更加一目了然。为了检验计算结果是否符合实际情况,通过一种间接的方法对磁屏蔽效能进行测试。对比分析以上的计算结果... 详细信息

提出了磁屏蔽效能问题的三维有限元模型的建立方法,应用ANSYS软件得到磁屏蔽效能为28.78,并将结果绘制成曲线,使结果更加一目了然。为了检验计算结果是否符合实际情况,通过一种间接的方法对磁屏蔽效能进行测试。对比分析以上的计算结果和测试结果,可以得出结论:利用有限元法进行磁屏蔽效能计算,对直流传感器的磁屏蔽效能估算具有一定的指导意义。

关键词：计量学磁屏蔽有限元法屏蔽效能