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永磁同步电机转子初始位置的检测方法

电机与控制学报 2012年第1期16卷 62-66页

作者：王冉珺刘恩海中国科学院光电技术研究所四川成都610209 中国科学院研究生院北京100039

针对永磁同步电机初始位置检测已有方法依赖电机参数,电流相位提取算法复杂,并在检测过程中会造成转子发生转动等问题,提出一种基于高频电压信号注入检测电机初始位置的方法。该方法通过对高频电压响应的电流进行解调、滤波和最小二乘... 详细信息

针对永磁同步电机初始位置检测已有方法依赖电机参数,电流相位提取算法复杂,并在检测过程中会造成转子发生转动等问题,提出一种基于高频电压信号注入检测电机初始位置的方法。该方法通过对高频电压响应的电流进行解调、滤波和最小二乘拟合处理后,再计算出正弦化响应电流最大值时的相位,便得到获取转子初始位置信息,最后利用磁路饱和凸极效应,判定永磁体的极性。仿真及实验结果表明,该方法能准确检测出转子初始位置,不会使转子发生移动,也不需要知道电机的参数,硬件结构简单。位置检测的平均误差为3.33°,可满足永磁同步电机的平稳启动需求。

关键词：永磁同步电机转子初始位置高频注入磁路饱和最小二乘

Microcosm study on fate and dynamics of mangrove tannins during leaf litter leaching

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Ecological Processes 2023年第1期12卷 520-533页

作者： hai-Chao Zhou Hui-Xing Kang Jian Wei Chang-jun Gao Muzammil Hussain Yi-Jian Fu Ming-Dang Li Feng-Lan Li Steven Jing-Liang Xu Fred Wang-Fat Lee Ming-Guo Jiang Yi-Bing Wang Xiao-Xia Chen Nora Fung-Yee Tam Tao Lang Greater Bay Area Coastal Mangrove Wetland Research&Development Centre MNR Key Laboratory for Geo-Environmental Monitoring of Great Bay AreaCollege of Life Sciences and OceanographyShenzhen UniversityShenzhen 518060China Institute of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of Ministry of EducationPeking UniversityBeijing 100091China Guangdong Provincial Key Laboratory of Silviculture Protection and UtilizationGuangdong Academy of ForestryGuangzhou 510520China School of Science and Technology The Hong Kong Metropolitan UniversityKowloonHong Kong 999077SARChina Guangxi Key Laboratory for Polysaccharide Materials and Modifications School of Marine Sciences and BiotechnologyGuangxi Minzu UniversityNanning 530008China State Key Laboratory of Marine Pollution City University of Hong KongKowloonHong Kong 999077SARChina

Background Mangrove tannins can participate in wetland biogeochemical ***,their fate and dynamics during leaf litter leaching have yet to be elucidated in coastal aquatic *** By using a simulated microcosm experiment,changes in leaf litter mass and tannin compounds,including total phenolics(TP),extractable condensed tannins(ECT),and bound condensed tannins(BCT),were examined in the litters and leachates of four common mangrove species:Kandelia obovata(Ko),Aegiceras corniculatum(Ac),Sonneratia apetala(Sa),and Avicennia marina(Am).Results Leaching caused a notable decline in litter mass,TP,and ECT in the leaf litter of Ko,Ac,Sa,and Am,while BCT increased significantly in Ko and *** in foliar TP was higher than in leaf litter mass,and loss in foliar ECT was higher than in TP of Ko and Ac,but Sa showed the opposite *** temporal changes of TP and ECT concentrations in leachates followed a similar trend,with an initial increase followed by a *** dynamics in Ko and Ac leachates correlated with their TP concentrations,while in Sa leachate,the peak ECT occurred 72 h later than its TP *** leachate ECT concentrations were highest in Ac,followed by Ko,and significantly lower in *** peak TP and ECT proportions in leachates accounted for 9.2-23.9%and 7.7-9.4%of the total decreases in foliar TP and ECT,*** During the leaching process,tannins’fate was species-specific,while the dynamics were almost similar.

关键词： Mangrove tannins Leaf litter decomposition Leaching Total phenolics Condensed tannins

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Isolation and short term cultivation of swine hepatocytes for bioartificial liver support system

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Hepatobiliary & Pancreatic Diseases International 2005年第2期4卷 249-253页

作者： jun Li, Lan-Juan Li, Hong-Cui Chao, qian Yang, Xiao-Li Liu, Ji-Fang Sheng, hai-Ying Yu and Jian-Rong Huang Hangzhou, China Key Laboratory of Infectious Disease, Ministry of Pub- lic Health of China Institute of Infectious Disease, Department of Infectious Diseases, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China Department of Infectious Diseases The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China. lilj@***

BACKGROUND: The demand for the clinical use of hepa- tocytes is increasing. The aim of this study was to develop a method for procurement of high qualitative pig hepatocytes and to evaluate the state of freshly isolated and cultured hepatocytes. METHODS: The domestic extracorporeal circulating perfu- sion apparatus was used to isolate and harvest swine hepato- cytes by the two-step perfusion method with EDTA and collagenase. The viability, function and morphology of the freshly isolated and cultured cells were evaluated and ob- served by the trypan blue exclusion test, biochemical mea- surements, phase contrast microscopy and transmission electron micrography (TEM). RESULTS: The total yield of isolated hepatocytes reached to 1.5(±0.4)×l010 per liver with a viability of 92(±5)%, and the purity of hepatocytes reached to 98% Immediately after isolation, phase-contrast microscope and TEM showed that undamaged hepatocytes appeared bright, translucent and spherical in shape, with a characteristic well-contrasted border. After 24 hours, the concentrations of alanine aminotransferase (ALT), aspartate aminotrans- ferase ( AST ), lactate dehydrogenase ( LDH ), albumin (ALB), creatinine (Cr) and blood urea nitrogen (BUN) in the fluid of culture were declined significantly. CONCLUSION: This method of procuring swine hepato- cytes could get high quality cells with active metabolic function.

关键词： bioartificial liver support system porcine hepatocytes cell isolation cell transplantation

多层面、多维度输电线路运维辅助决策专家系统

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信息与控制 2015年第5期44卷 612-621页

作者：邓军陈东秦立斌别睿钱海樊友平中国南方电网有限责任公司超高压输电公司检修试验中心广东广州510663 武汉大学电气工程学院湖北武汉430072

为了电力系统输电线路安全稳定运行,提出了基于运维自动化平台的多层面、多维度输电线路运维辅助决策专家系统,给出了专家系统的工程方案设计和应用功能设计.从数据处理、高级应用和展示3个层面构建了输电线路运维辅助决策专家系统的总... 详细信息

为了电力系统输电线路安全稳定运行,提出了基于运维自动化平台的多层面、多维度输电线路运维辅助决策专家系统,给出了专家系统的工程方案设计和应用功能设计.从数据处理、高级应用和展示3个层面构建了输电线路运维辅助决策专家系统的总体架构,分析了包括智能预警、故障诊断、状态评价、风险评估、经济性评估、多维度分析以及数据处理等关键技术问题,阐述了系统的硬件系统设计,最后给出了系统运行的部分实例,验证了该专家系统能够为输电线路的安全稳定运行和运行决策提供技术支撑.

关键词：输电线路专家系统辅助决策状态评价风险评估

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城市固废焚烧过程数据驱动建模与自组织控制

自动化学报 2023年第3期49卷 550-566页

作者：丁海旭汤健乔俊飞北京工业大学信息学部北京100124 智慧环保北京实验室北京100124

城市固废焚烧(Municipal solid waste incineration,MSWI)是处置城市固废(Municipal solid waste,MSW)的主要手段之一.中国MSW来源范围广、组分复杂、热值波动大,其焚烧过程通常依靠人工干预,这导致MSWI过程智能化水平较低且难以满足日... 详细信息

城市固废焚烧(Municipal solid waste incineration,MSWI)是处置城市固废(Municipal solid waste,MSW)的主要手段之一.中国MSW来源范围广、组分复杂、热值波动大,其焚烧过程通常依靠人工干预,这导致MSWI过程智能化水平较低且难以满足日益提升的控制需求.MSWI具有多变量耦合、工况漂移等诸多不确定性特征,因而难以建立其被控对象模型并设计在线控制器.针对以上问题,提出了一种面向MSWI过程的数据驱动建模与自组织控制方法.首先,构建了基于多输入多输出Takagi Sugeno模糊神经网络(Multi-input multi-output Takagi Sugeno fuzzy neural network,MIMO-TSFNN)的被控对象模型;然后,设计了基于多任务学习的自组织模糊神经网络控制器(Multi-task learning selforganizing fuzzy neural network controller,MTL-SOFNNC)用于同步控制炉膛温度与烟气含氧量,其通过计算神经元的相似度与多任务学习(Multi-task learning,MTL)能力对控制器结构进行自组织调整;接着,通过Lyapunov定理对MTLSOFNNC稳定性进行了证明;最后,通过北京市某MSWI厂的过程数据验证了模型与控制器的有效性.

关键词：城市固废焚烧多任务学习自组织控制数据驱动建模模糊神经网络

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液压驱动仿生推进器运动特性的数值仿真

兵工学报 2010年第11期31卷 1475-1480页

作者：徐海军潘存云张代兵谢海斌国防科技大学机电工程与自动化学院湖南长沙410073

奇鳍/对鳍(MPF)模式的波动鳍有着许多出众的优点,其推进性能受自身结构及波形变化规律的影响较大。根据液压驱动的仿生推进器运动学模型,从理论上分析了液压参数对波形参数的影响。在Matlab软件中,搭建了仿生推进器液压系统的运动仿真模... 详细信息

奇鳍/对鳍(MPF)模式的波动鳍有着许多出众的优点,其推进性能受自身结构及波形变化规律的影响较大。根据液压驱动的仿生推进器运动学模型,从理论上分析了液压参数对波形参数的影响。在Matlab软件中,搭建了仿生推进器液压系统的运动仿真模型,研究了液压系统参数对多个波动鳍波形参数之间关联影响,提出了消除波形参数关联变化的补偿方法。研究了仿生推进器在启动、停止过程中波形参数的变化规律。开展了液压驱动的仿生推进器装置的相关试验,验证了前面分析得出的结论。对仿生推进器运动特性的研究,可以进一步全面地了解其动态特性,对深入研究波动鳍的推进机理、提高仿生推进器的性能等具有重要的意义。

关键词：机械设计液压驱动波动鳍仿生推进器运动特性

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船艏自由落体砰击载荷模型试验研究

船舶力学 2020年第4期24卷 445-455页

作者：司海龙赵南胡嘉骏中国船舶科学研究中心江苏无锡214082

本文对船艏自由落体砰击载荷进行了模型试验研究,根据不同的落体高度与入水角进行了多次试验,研究了落体高度、入水角等因素对入水速度、砰击载荷及结构响应的影响。研究结果表明:船体入水速度、砰击压力、结构响应等随着落体高度的增... 详细信息

本文对船艏自由落体砰击载荷进行了模型试验研究,根据不同的落体高度与入水角进行了多次试验,研究了落体高度、入水角等因素对入水速度、砰击载荷及结构响应的影响。研究结果表明:船体入水速度、砰击压力、结构响应等随着落体高度的增大而增大;模型入水过程中,各测量点砰击压力峰值发生时刻存在一定的时间差;结构响应峰值发生时刻也存在一定的时间差;由于斜升角较小,球鼻艏底部的砰击压力峰值最大;外飘区域的砰击压力最大值仅为球鼻艏底部的30%~50%;同一水线面上,从船艏模型艏端向艉端砰击压力峰值逐渐减小;对同一横剖面,外飘下部区域的砰击压力峰值大于外飘上部区域的砰击压力峰值;由于砰击压力对外界影响因素非常敏感,砰击压力与结构响应具有一定的离散性。

关键词：自由落体砰击载荷结构响应入水角

Magnetic resonance imaging of the extraocular muscles and corresponding cranial nerves in patients with special forms of strabismus

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Chinese Medical Journal 2009年第24期122卷 2998-3002页

作者： JIAO Yong-hong ZHAO Kan-xing WANG Zhen-chang qian Xue-han WU Xiao MAN Feng-yuan LU Wei SHE hai-cheng Beijing Tongren Eye Centre Beijing Ophthalmology & Visual Science Key Laboratory Beijing Tongren Hospital Capital Medical University Beijing 100730 China Beijing Tongren Imaging Centre Beijing Tongren Hospital Capital Medical University Beijing 100730 China Tianjin Eye Hospital Clinical College of Ophthalmology TianjinMedical University Tianjin Tianjin 300020 China

Background With the technical advances, magnetic resonance imaging （MRI） is now sensitive enough to detect subtle structural abnormalities of ocular motor nerves arising from the brainstem and orbits of living subjects. This study was designed to delineate the MRI characteristics in patients with special forms of strabismus. Methods A total of 29 patients with special forms of strabismus underwent orbital and intracalvafium MRI. Imaging of the ocular motor nerves in the brainstem was performed in 0.8 mm thickness image planes using the three-dimensional fast imaging employing steady-state acquisition （3D-FIESTA） sequence. Nerves to extraocular muscles （EOMs）, EOMs and their associated connective tissues were imaged with T1 weighting in tri-planar scans by dual-phased coils within 2.0 mm thick planes. Results Patients with congenital fibrosis of the extraocular muscles exhibited hypoplasia of the oculomotor （CN3）, abducens （CN6）, trochlear （CN4） nerves, and the EOMs; hypoplasia of CN6 in the brainstem and an extra branch of the inferior division of CN3 to the lateral rectus were the most common but not the only presentation of Duane＇s retraction syndrome. Hypoplasia of CN6, facial （CN7） and hypoglossal （CN12） nerves were revealed in patients with MSbius syndrome. In a rare case of bilateral synergistic convergence and divergence, an enlarged branch of CN3 to the medial rectus and a questionable branch of CN3 to the inferior rectus bilaterally were found. Conclusion MRI can reveal subtle structures of the ocular motor nerves and their corresponding EOMs. This can provide valuable information regarding pathogenesis in some special forms of strabismus.

关键词： magnetic resonance imaging ocular motor nerve extraocular muscle strabismus

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吕祖谦门人及吕学与浙东学术的发展关系

浙江师范大学学报（社会科学版） 2014年第2期39卷 21-28页

作者：杜海军广西师范大学文学院广西南宁541004

吕祖谦是南宋著名的思想家、教育家、文学家,是乾淳年间最受欢迎且成就最高的老师。当时多云从教千人,今可考者初步统计仍有219人。吕祖谦门下多出俊杰,或为政治领袖,或为学术领袖。这些门下为宋元社会发展取得的成就作出了重大贡献,使... 详细信息

吕祖谦是南宋著名的思想家、教育家、文学家,是乾淳年间最受欢迎且成就最高的老师。当时多云从教千人,今可考者初步统计仍有219人。吕祖谦门下多出俊杰,或为政治领袖,或为学术领袖。这些门下为宋元社会发展取得的成就作出了重大贡献,使吕祖谦的学术对后代发挥了影响。浙东学术成为一个时代的学术、一种独立的学术,成为中国学术史上一个重要的发展环节,时移境迁不断地发展壮大,这一现象发生在浙江,而不是朱熹所在的福建,或陆九渊所在的江西以及其他地区,是与吕祖谦的倡导与亲身实践分不开的。今人多将浙东学术的发展归功于朱熹而忽略吕祖谦,有些数典忘祖,这是受朱陆门户恶争影响的结果。我们需要开拓、改换思路,加大对吕祖谦甚至其门生的研究,甩掉多年门户之争留下的惯性,追寻吕祖谦学术的真成就,追寻南宋学术研究的新思路。

关键词：吕祖谦门人吕学发展