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CSEE Journal of Power and Energy Systems 2021年第2期7卷 250-260页

作者： Jianhong Gao Moufa Guo duan-Yu chen College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China Department of Electrical Engineering Yuan Ze UniversityTaoyuan 32003TaiwanChina

Effective features are essential for fault *** to the faint characteristics of a single line-to-ground(SLG)fault,fault line detection has become a challenge in resonant grounding distribution *** paper proposes a novel fault line detection method using waveform fusion and one-dimensional convolutional neural networks(1-D CNN).After an SLG fault occurs,the first-half waves of zero-sequence currents are collected and superimposed with each other to achieve waveform *** compelling feature of fused waveforms is extracted by 1-D CNN to determine whether the fused waveform source contains the fault ***,the 1-D CNN output is used to update the value of the counter in order to identify the fault *** the lack of fault data in existing distribution systems,the proposed method only needs a small quantity of data for model training and fault line *** addition,the proposed method owns fault-tolerant *** if a few samples are misjudged,the fault line can still be detected correctly based on the full output results of 1-D *** results verified that the proposed method can work effectively under various fault conditions.

关键词： Fault line detection one-dimensional convolutional neural network resonant grounding distribution systems waveform fusion

Intermittent Arc Fault Detection Based on Machine Learning in Resonant Grounding Distribution Systems

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 599-611页

作者： Ye Tian Mou-Fa Guo duan-Yu chen College of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China Department of Electrical Engineering Yuan Ze UniversityTaiwan 32003China Fuzhou Power Supply Company of State Grid Fujian Electric Power Co. Ltd.Fuzhou 350009China

In resonant grounding systems,most single-phaseto-ground faults evolve from IAFs(Intermittent Arc Faults).Earlier detection of IAFs can facilitate fault *** work proposes a novel method based on machine learning for detecting IAFs in three ***,the feature of zero-sequence current is automatically extracted and selected by a newlydesigned FINET(“For IAFs,Neuron Elaboration Net”),instead of traditional feature selection based on time-frequency ***,data of the zero-sequence current divided by different time windows are successively input into the trained FINET.A proposed PSF(principal-subordinate factor)analyses the results obtained from FINET to improve anti-interference in the mentioned IAF detection *** using PSCAD/EMTDC software simulation data show the proposed method is feasible and highly *** addition,the detection result of on-site recorded data demonstrates the effectiveness of the proposed method in practical resonant grounding systems.

关键词： Resonant grounding distribution systems intermittent arc faults(IAFs)detection “For IAFs Neuron Elaboration Net”(FINET) principal-subordinate factor(PSF)

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物联网设备识别及异常检测研究综述

软件学报 2024年第1期35卷 288-308页

作者：樊琳娜李城龙吴毅超段晨鑫王之梁林海杨家海清华大学网络科学与网络空间研究院北京100084 北京信息科学与技术国家研究中心北京100084 国防科技大学信息通信学院湖北武汉430019

随着物联网技术的发展,物联网设备广泛应用于生产和生活的各个领域,但也为设备资产管理和安全管理带来了严峻的挑战.首先,由于物联网设备类型和接入方式的多样性,网络管理员通常难以得知网络中的物联网设备类型及运行状态.其次,物联网... 详细信息

随着物联网技术的发展,物联网设备广泛应用于生产和生活的各个领域,但也为设备资产管理和安全管理带来了严峻的挑战.首先,由于物联网设备类型和接入方式的多样性,网络管理员通常难以得知网络中的物联网设备类型及运行状态.其次,物联网设备由于其计算、存储资源有限,难以部署传统防御措施,正逐渐成为网络攻击的焦点.因此,通过设备识别了解网络中的物联网设备并基于设备识别结果进行异常检测,以保证其正常运行尤为重要.近几年来,学术界围绕上述问题开展了大量的研究.系统地梳理物联网设备识别和异常检测方面的相关工作.在设备识别方面,根据是否向网络中发送数据包,现有研究可分为被动识别方法和主动识别方法.针对被动识别方法按照识别方法、识别粒度和应用场景进行进一步的调研,针对主动识别方法按照识别方法、识别粒度和探测粒度进行进一步的调研.在异常检测方面,按照基于机器学习算法的检测方法和基于行为规范的规则匹配方法进行梳理.在此基础上,总结物联网设备识别和异常检测领域的研究挑战并展望其未来发展方向.

关键词：物联网设备识别异常检测

An Improved Adaptive model for Information Recommending and Spreading

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Chinese Physics Letters 2012年第4期29卷 240-243页

作者： chen duan-Bing GAO Hui Web Sciences Center University of Electronic Science and Technology of ChinaChengdu 611731

People in the Internet era have to cope with information overload and expend great effort on finding what they *** experiments indicate that recommendations based on users' past activities are usually less favored than those based on social relationships,and thus many researchers have proposed adaptive algorithms on social ***,in those methods,quite a number of users have little chance to recommend information,which might prevent valuable information from *** present an improved algorithm that allows more users to have enough followers to spread *** results demonstrate that both recommendation precision and spreading effectiveness of our method can be improved significantly.

关键词： enough users finding

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分步精超角接触球轴承外圈沟道工艺试验研究

机械设计与制造 2024年第1期395卷 165-169页

作者：高新江赵华东张瑞段玥晨郑州大学机械与动力工程学院河南郑州450001 河南省智能制造研究院河南郑州450001

为提高角接触球轴承外圈沟道精超的加工精度及加工效率,基于沟道表面在精超加工过程中的变化特点,对轴承外圈的精超加工部分进行深入研究,细分为粗精超、精超两步,采用正交试验法来对每一步加工参数进行优化,将优化得出的结果和常规的... 详细信息

为提高角接触球轴承外圈沟道精超的加工精度及加工效率,基于沟道表面在精超加工过程中的变化特点,对轴承外圈的精超加工部分进行深入研究,细分为粗精超、精超两步,采用正交试验法来对每一步加工参数进行优化,将优化得出的结果和常规的一步精超试验结果作对比分析,试验结果表明:相较于常规的一步精超,采用分步精超能够将轴承超精加工精度提高10.42%,并且超精加工时间减少2s,说明分步精超的加工精度及加工效率均要高于常规的一步精超。

关键词：角接触球轴承分步精超正交试验法加工精度加工效率

Serving Our Science and Community Better

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植物分类学报 2008年第1期46卷 1-2页

作者： Zhi-duan chen Yin-Long Qiu

Journal of Systematics and Evolution (JSE) has just debuted with its first issue. While it continues the tradition of its predecessor, Acta Phytotaxonomica Sinica (APS), in publishing

关键词：期刊编辑出版《植物分类学报》《系统分类与进化学报》

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基于多传感器信息融合的水工闸门故障诊断

中国农村水利水电 2024年第2期 96-102页

作者：李凯旋张钰奇付春健段玥晨郑州大学机械与动力工程学院河南郑州450001 河南省智能制造研究院河南郑州450001

针对水工闸门安全检修困难、检修效率低的问题,提出了一种基于支持向量机(Support vector machine,SVM)和改进D-S证据理论的信息融合水工闸门故障诊断方法。该方法通过提取不同传感器诊断信号小波包信息熵特征构建特征子空间,然后在每... 详细信息

针对水工闸门安全检修困难、检修效率低的问题,提出了一种基于支持向量机(Support vector machine,SVM)和改进D-S证据理论的信息融合水工闸门故障诊断方法。该方法通过提取不同传感器诊断信号小波包信息熵特征构建特征子空间,然后在每个特征子空间构建诊断子网络,最后使用改进证据理论对每个诊断子网络的输入进行决策层融合,从而水工闸门的多信息融合诊断结果。闸门故障诊断实验结果显示,信息融合的闸门故障诊断方法可有效识别弧形闸门故障种类,其故障诊断准确率达到了98.33%,同时诊断可靠度高,各类故障的诊断不确定度均小于1%。实验结果验证了智能故障诊断方法用于水工闸门领域的可行性,对于改进水工闸门故障检修方式,推动水利工程智能化的发展具有重大意义。

关键词：支持向量机改进证据理论信息融合水工闸门故障诊断

Optimizing the operation of the Qingshitan Reservoir in the Lijiang River for multiple human interests and quasi-natural flow maintenance

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Journal of Environmental Sciences 2012年第11期24卷 1923-1928页

作者： Qiuwen chen duan chen Ruiguang Han Ruonan Li Jinfeng Ma Koen Blanckaert Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Three Gorges University Yichang 443002China Changjiang River Scientific Research Institute Wuhan 430010China Laboratory of Hydraulic Constructions School of ArchitectureCivil and Environment EngineeringLausanneSwitzerland Haihe Water Conservancy Commission Tianjin 300170China

For reservoir operation, maintaining a quasi-natural flow regime can benefit river ecosystems, but may sacrifice human interests. This study took the Qingshitan Reservoir in the Lijiang River as a case, and developed an optimization model to explore a trade-off solution between social-economic interests and nature flow maintenance on a monthly base. The objective function considered irrigation, cruise navigation and water supply aspects. An index of flow alteration degree was proposed to measure the difference between the regulated discharge and the natural flow. The index was then used as an additional constraint in the model besides the conventional constraints on reservoir safety. During model solving, different criteria were applied to the index, representing various degrees of alteration of the natural flow regime in the river. Through the model, a relationship between social-economic interests and flow alteration degree was established. Finally, a trade-off solution of the reservoir operation was defined that led to a favorable social-economic benefit at an acceptable alteration of the natural flow.

关键词： reservoir operation optimization model flow alteration trade-off solution

Dramatic impact of metric choice on biogeographical regionalization

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Plant Diversity 2020年第2期42卷 67-73页

作者： Jian-Fei Ye Yun Liu Zhi-duan chen State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China Beijing Botanical Garden.Institute of Botany Chinese Academy of SciencesBeijing W0093China

For a quantitative biogeographical regionalization,the choice of an appropriate dissimilarity index to measure pairwise distances is *** different metrics have been used,but there is no specific study to test the impact of metric choice on biogeographical *** herein applied a hierarchical cluster analysis on the mean nearest taxon distance(MNTD)and the phylogenetic turnover component of the SФrensen dissimilarity index(pβsim)pairwise distances to generate two schemes of phylogenetic regio nalization of the Chinese flora,and then evaluated the effect of metric *** regionalization based on MNTD was influenced by richness differences,but regionalization based on pβsim can clearly reflect the evolutionary history of the Chinese *** provided a brief description of the five regions identified by pβsim,and the regionalization can help develop strategies to effectively conserve the taxa and floristic regions with different origins and evolutionary histories.

关键词： Angiosperms Chinese flora Dissimilarity index Distance metrics Spatial turnover

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针刺联合摇髋法治疗骶髂关节紊乱临床观察

河北中医 2024年第6期46卷 985-988页

作者：刘炼游菲段晨胡星华中科技大学同济医学院附属武汉中心医院康复医学科湖北武汉430014

目的观察针刺联合摇髋法治疗骶髂关节紊乱的临床疗效。方法将96例骶髂关节紊乱患者按照随机数字表法分为2组,对照组48例予针刺治疗,治疗组48例在对照组治疗基础上应用摇髋法治疗。2组均1周为1个疗程,连续治疗4个疗程。比较2组疗效;比较... 详细信息

目的观察针刺联合摇髋法治疗骶髂关节紊乱的临床疗效。方法将96例骶髂关节紊乱患者按照随机数字表法分为2组,对照组48例予针刺治疗,治疗组48例在对照组治疗基础上应用摇髋法治疗。2组均1周为1个疗程,连续治疗4个疗程。比较2组疗效;比较2组治疗前和治疗2、4周数字疼痛强度量表(NRS)评分、Roland-Morris功能障碍调查表(RMDQ)评分、Oswestry功能障碍指数(ODI)评分变化;比较2组治疗前后腰椎活动度变化。结果治疗组优良率87.50%(42/48),对照组优良率70.83%(34/48),治疗组疗效优于对照组(P<0.05)。2组治疗2、4周NRS评分、RMDQ评分、ODI评分均较本组治疗前降低(P<0.05),治疗4周NRS评分、RMDQ评分、ODI评分均较本组治疗2周降低(P<0.05);治疗2、4周治疗组NRS评分、RMDQ评分、ODI评分均低于对照组治疗同期(P<0.05)。2组治疗后腰椎前伸、后屈、左旋、右旋活动度均较本组治疗前增加(P<0.05),且治疗组增加更明显(P<0.05)。结论针刺联合摇髋法治疗骶髂关节紊乱,可有效缓解患者下腰痛,改善腰椎功能。

关键词：关节不稳定性骶髂关节针刺疗法推拿