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Study on operation voltage monitoring and electrothermal coupling simulation of electric multiple unit(EMU)roof arrester

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High Voltage 2022年第2期7卷 357-368页

作者： Qizhe Zhang Shenghui Wang Kaixuan Sun xinghao Dong Mingliang Liu Fangcheng Lü State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingChina Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power UniversityBaodingChina

The roof arrester of electric multiple units(EMU)can efficiently limit the overvoltage,and ensure the safe operation of the EMU electrical *** the process of high‐speed operation,the traction power supply system is often affected by *** addition,roof arrester explosion accidents occasionally *** this paper,the on‐line voltage measurement system of the EMU arrester is *** analysing a large number of voltage waveforms,the abnormal voltage is divided into three categories:over‐phase voltage,high harmonic voltage and steep impulse *** charac-teristics of abnormal voltage waveforms are then *** electrothermal coupling simulation model of the arrester is developed,and the current response and temperature distribution of the arrester under abnormal voltage are *** impact of the impulse voltage energy on the arrester temperature is studied by applying a triangular wave voltage to the ***,some suggestions are proposed for the operation and maintenance of the roof arrester.

关键词： operation traction coupling

A scalable model for network situational awareness based on Endsley＇ s situation model

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High Technology Letters 2007年第4期13卷 395-401页

作者：胡威 Li Jianhua Chen Xiuzhen Jiang xinghao Zuo Min Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 P.R. China

The paper introduces the Endsley＇ s situation model into network security to describe the network security situation, and improves Endsley＇s data processing to suit network alerts. The proposed model contains the information of incident frequency, incident time and incident space. The HoneyNet dataset is selected to evaluate the proposed model in the evaluation. The paper proposes three definitions to depict and predigest the whole situation extraction in detail, and a fusion component to reduce the influence of alert redundancy on the total security situation. The less complex extraction makes the situation analysis more efficient, and the fine-grained model makes the analysis have a better expansibility. Finally, the situational variation curves are simulated, and the evaluation results prove the situation model applicable and efficient.

关键词： network situational awareness data fusion security situation security management

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基于卷积神经网络的游泳连续动作检测

微型电脑应用 2024年第5期40卷 63-67页

作者：宋耀伟陈星豪张大千西安体育学院体育教育学院陕西西安710068 哈尔科夫国立经济大学国际关系与新闻学院乌克兰哈尔科夫洲61002

在许多体育项目中,分析运动员在比赛中的视频能够清晰了解该运动项目的技术规律。在游泳运动中,划水效率是教练常用的指标,要求对每一次划水动作进行详细的标记。因此在这里提出了一种利用卷积神经网络自动检测连续视频中的离散事件的... 详细信息

在许多体育项目中,分析运动员在比赛中的视频能够清晰了解该运动项目的技术规律。在游泳运动中,划水效率是教练常用的指标,要求对每一次划水动作进行详细的标记。因此在这里提出了一种利用卷积神经网络自动检测连续视频中的离散事件的方法。该方法学习从帧窗口到平滑一维目标信号上的点的映射,峰值表示一次划水的位置,评估为滑动窗口。证明了提出的方法在野外检测游泳动作的任务中效果良好,并在实验中表明提出的方法能够满足实际需求。

关键词：游泳动作评估人工智能卷积神经网络体育训练连续动作

High Performance Soft Electrochemical Actuators Based on Hierarchical Conductive Polymer Ionogels

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Journal of Bionic Engineering 2023年第6期20卷 2755-2763页

作者： Hongwei Hu Shengtao Zhang Yan Li xinghao Hu Lin Xu Aixin Feng Guanggui Cheng Jianning Ding Zhejiang Provincial Key Laboratory of Laser Processing Robotics College of Mechanical and Electrical EngineeringWenzhou UniversityWenzhou325035China Institute of Intelligent Flexible Mechatronics Jiangsu UniversityZhenjiang212013China School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang212100China School of Mechanical Engineering Yangzhou UniversityYangzhou225127China Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering Changzhou UniversityChangzhou213164China Ruian Graduate School of Wenzhou University Ruian325207ZhejiangChina

Electrochemical actuators based on conductive polymers are emerging as a strong competitive in the field of soft actuators because of their intrinsically conformable/elastic nature,low cost,low operating voltage and air-working *** development has shown that adding electroactive materials,such as CNT and graphene,can improve their actuation *** the complex material systems used,their output strains(one of the key factors)are generally lower than 1%,which limited further applications of them in multiple ***,we report soft electrochemical actuators based on conductive polymer ionogels by embedding polyaniline particles between the PEDOT:PSS *** show that such a hierarchical structure not only leads to a high conductivity(1250 S/cm)but also improved electrochemical *** a low operating voltage of 1 V,the maximum strain of these soft actuators reaches an exceptional value of 1.5%,with a high blocking force of 1.3 *** these high-performance electrochemical actuators,we demonstrate soft grippers for manipulating object and a bionic flower stimulated by an electrical *** work sets an important step towards enabling the enhanced performance of electrochemical actuators based on conductive polymers with designed microstructures.

关键词： Conductive polymer Soft actuator Polyaniline PEDOT:PSS Bioinspired actuator

Coiled Polymer Artificial Muscles Having dual-Mode Actuation with Large Stress Generation

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Journal of Bionic Engineering 2023年第4期20卷 1626-1634页

作者： xinghao Hu Runmin Liu Kai Zhao Yilun Wang Xianfu Bao Lin Xu Guanggui Cheng Jianning Ding Institute of Intelligent Flexible Mechatronics School of Mechanical EngineeringJiangsu UniversityZhenjiang212013China School of Mechanical Engineering Yangzhou UniversityYangzhou225009China

Coiled polymer artificial muscles with both large tensile stroke and giant force generation are needed for practical applications in robotics,soft exosuits,and ***,most polymer yarn artificial muscles cannot generate a large force or ***,we report an inexpensive Twisted and Coiled Polymer artificial muscle(TCP)that performs both large isobaric and isometric *** TCP can generate a tensile stroke of 20.1%and a specific work capacity of up to 1.3 kJ kg^(−1) during temperature changes from 20 to 180℃.Moreover,the nylon yarn artificial muscle produced a reversible output stress of 28.4 MPa,which is 100 times larger than human skeletal muscle.A robot arm and a simple gripper were made to demonstrate the isobaric actuation and isometric actuation of our TCP muscle,***,the polymer artificial muscles with dual-mode actuation show potential applications in the field of robotics,grippers,and exoskeletons and so on.

关键词： Coiled nylon muscles dual-mode actuation Large stroke Stress generation

热浪频次及间隔时间对闽楠和木荷苗木水力结构和非结构性碳水化合物的影响

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生态学报 2024年第3期44卷 1251-1263页

作者：张子雷余海霞曲鲁平汤行昊王浩王朝昭刘南王艺璇邵长亮董刚福建农林大学林学院福州350002 福建省林业科学研究院福州350002 中国农业科学院农业资源与农业区划研究所北京100081 山西大学生命科学学院太原030006

近年来亚热带地区极端气候事件热浪发生频率增加,热浪频次及间隔时间的变化使热浪发生的模式及其对植物的胁迫方式更加多样化。高频热浪不仅通过热胁迫影响植物的碳固持速率,还会间接形成水分胁迫造成植物水力结构发生障碍,影响碳水化... 详细信息

近年来亚热带地区极端气候事件热浪发生频率增加,热浪频次及间隔时间的变化使热浪发生的模式及其对植物的胁迫方式更加多样化。高频热浪不仅通过热胁迫影响植物的碳固持速率,还会间接形成水分胁迫造成植物水力结构发生障碍,影响碳水化合物的运输。然而,目前亚热带树木水力结构和非结构性碳水化合物(NSC)对复杂热浪的模式的响应仍不明确。以亚热带主要阔叶树种闽楠(Phoebe bournei)和木荷(Schima superba)苗木为研究对象进行了热浪模拟试验,关注不同热浪频次(单次,两次)及重复热浪间隔时间(短间隔、中间隔、长间隔)对苗木茎部水力结构特征及NSC的影响,使用冲洗法测定水力结构中的导水率(Kh)、最大导水率(K_(max))、比导率(K_(s))、木质部栓塞百分数(PLC),使用蒽酮-硫酸比色法测定茎段非结构性碳水化合物含量。结果表明,(1)闽楠和木荷的水力结构和非结构性碳水化合物在树种间存在显著差异;(2)不同热浪频次对闽楠和木荷的K_(max)和PLC影响存在显著差异;(3)重复热浪间隔时间变长,木荷茎栓塞减轻,而闽楠茎栓塞增加,且植株栓塞越严重,茎NSC含量越少。总体上,闽楠的水力传输系统对热浪抗性较弱,在热浪后栓塞严重,导水率下降且无法完全恢复,且NSC含量与栓塞程度相关性较弱;而木荷水力传输系统抗性较强,在热浪后导水能力可能恢复至未受干扰水平,且其恢复程度与NSC含量紧密相关。该研究结果表明,高频热浪的发生会显著影响闽楠和木荷苗木茎部的导水能力,且不同间隔时间的重复热浪事件对植物水力结构的影响存在差异性,并且两个亚热带阔叶树种对热浪伴随的高温和水分胁迫的耐受性和耐受机制存在差异。

关键词：热浪频次间隔时间闽楠木荷水力结构非结构性碳水化合物

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Spatio-temporal patterns of zooplankton in a main-stem dam affected tributary: a case study in the Xiangxi River of the Three Gorges Reservoir, China

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Science China(Life Sciences) 2019年第8期62卷 1058-1069页

作者： xinghao Li Jie Huang Sabine Filker Thorsten Stoeck Yonghong Bi Yuhe Yu Weibo Song Laboratory of Protozoology Institute of Evolution and Marine BiodiversityOcean University of ChinaQingdao266003China Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences and State Key Laboratory of Freshwater Ecologyand BiotechnologyInstitute of HydrobiologyChinese Academy of SciencesWuhan430072China Department of Molecular Ecology University of Technology KaiserslauternKaiserslautern67663Germany Department of Ecology University of Technology KaiserslauternKaiserslautern67663Germany Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao266003China

As the ecologically important recipient channels for riverine ecosystems, tributaries provide unique microhabitats for microorganisms, among which zooplankton constitutes the most important heterotrophic organisms. In particular, the reduced water velocity caused by dams is more favorable for zooplankton development;therefore, dammed rivers are expected to support extremely diverse and abundant zooplankton communities and notably different spatiotemporal distribution patterns. So far,however, only very few molecular studies support these assumptions. Using high-throughput sequencing, a high number of 350 operational taxonomic units(OTUs;97% cutoff) were retrieved from 30 samples collected in the Xiangxi River, the nearest large tributary upstream of the Three Gorges Dam. Zooplankton did not show significant spatial distribution in the channel. Instead,the community structures varied significantly over sampling dates, corroborating the seasonal patterns found in lakes and ponds in the subtropical zone. As expected, the community compositions were deterministically governed by environmental filtering processes(phylogenetic clustering), in which water velocity appeared to be much less important than other investigated environmental factors. Moreover, most of the detected phylotypes(OTUs) had a relatively high(>90%) sequence similarity to previously deposited sequences, suggesting a mediocre degree of genetic novelty within the zooplankton communities in the Xiangxi River.

关键词： zooplankton high-throughput sequencing spatiotemporal distribution genetic novelty tributary main-stem dam

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基于多尺度法的多机非线性强迫振荡机理研究

智慧电力 2024年第5期52卷 52-59页

作者：甄星皓李永刚纪璇李亚斌沙叶楠周一辰新能源电力系统国家重点实验室(华北电力大学) 河北保定071003

随着高比例新能源电网的发展,电力系统呈现出更明显的非线性特征,可以采用多尺度法展示二次非线性对多机系统强迫振荡的影响。首先,建立多机系统强迫振荡模型,将系统数学模型进行多次恒等变换并进行简化,与单机系统相比,多机系统有着更... 详细信息

随着高比例新能源电网的发展,电力系统呈现出更明显的非线性特征,可以采用多尺度法展示二次非线性对多机系统强迫振荡的影响。首先,建立多机系统强迫振荡模型,将系统数学模型进行多次恒等变换并进行简化,与单机系统相比,多机系统有着更广泛的适用性。然后,利用多尺度法导出了非线性强迫振动稳态响应的幅频特性曲线和动态响应的近似一阶解析表达式,并分析关键参数对非线性强迫荡的影响。最后,以三机系统为例,验证了所提方法的准确性,并对由非线性引起的频率偏移和跳跃的现象做出了解释。

关键词：强迫振荡非线性多尺度法电力系统稳定性

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饱和状态下硫酸复盐的反应研究

化工管理 2024年第13期 39-44页

作者：王文科熊天兵王星浩马海生秦皇岛天鼎化工有限公司河北秦皇岛066003 秦皇岛华瀛磷酸有限公司河北秦皇岛066003

文章研究了饱和状态下硫酸盐之间存在的部分反应,是非饱和态下较难发现的。该反应存在一定规律,值得进一步探讨与研究。该反应可以为复合肥料的生产提供研究资料,特别是硝硫基复合肥中使用大量的硝铵磷、硫酸钾、硫酸铵、硫酸锰、硫酸... 详细信息

文章研究了饱和状态下硫酸盐之间存在的部分反应,是非饱和态下较难发现的。该反应存在一定规律,值得进一步探讨与研究。该反应可以为复合肥料的生产提供研究资料,特别是硝硫基复合肥中使用大量的硝铵磷、硫酸钾、硫酸铵、硫酸锰、硫酸镁等原料,复合肥中硫酸盐是以硫酸复盐的形式存在而非以简单化合物混合而成,会影响到复合肥产品强度与储存的稳定性。

关键词：饱和溶液硫酸复盐结晶水