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Integrative Conservation, Volume 4, Issue 3, Page 416-429, September 2025.Staghorn ferns are among the most highly valued ornamental plants but several species experience major extinction threats. Here we establish a DNA barcoding reference dataset to support reliable identification of cultivated staghorn ferns to secure species identity of individuals at all life stages that are used in ex situ and in situ conservation of ...
Kaikai Wang +6 more
wiley +1 more source
基于软打分机制——多模态融合的真实开关柜局部放电模式识别方法
Gaoya dianqi, 2023 局部放电类型与开关柜早期绝缘劣化程度密切相关，准确识别开关柜局部放电类型是改善开关柜运行状态，保障电网安全的重要手段。文中设计了真实开关柜中易产生的尖端放电、悬浮电位放电、强垂直分量沿面和弱垂直分量沿面放电4种局部放电类型。利用特高频传感器、暂态地电波传感器、超声传感器和高频电流线圈对开关柜的局部放电进行多模态融合检测，分析了同一缺陷下不同传感器的检测灵敏度以及不同缺陷类型的谱图特性。提取谱图的放电密度分布特征参量为正负峰值差Dpn、边沿积分差值Dei、前端均值差Dav ...
刘树慰 +5 more
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China's Eco‐Civilisation, Climate Leviathan, and Hobbesian Energy Transition
Antipode, Volume 57, Issue 3, Page 830-861, May 2025.Abstract Scholars have hitherto tended to theorise China's ecological civilisation project either as a form of environmental authoritarianism or as a vision of eco‐socialism. This paper contributes to the conversation by conducting a textual analysis of Chinese scholarly discussions on eco‐civilisation.
David Chen
wiley +1 more source
Gaoya dianqi, 2017 为了提取泄漏电流安全区内体现绝缘子污秽度的特征信息,在反复试验的基础上,测取了4种污秽度下XP-70型绝缘子串的泄漏电流,采用了自适应阈值法对原始信号进行消噪,提取出安全区内的3个特征量:有效值均值、有效值最大值和有效值标准差,分析得出这3个特征量与绝缘子表面等值附盐密度呈指数拟合关系。选择了400组泄漏电流有效值特征量作为训练与识别样本,建立了基于概率神经网络的绝缘子污秽度预测模型。仿真和试验结果对比表明,模型预测准确率达87.5%。研究结果不仅对线路绝缘子清扫决策有一定的指导作用 ...
汪万平, 陈伟根, 刘凡, 苏明虹
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, 2009 本文通过运用多元统计学的主成分分析方法,对2007年23家上市公司反映盈利能力的多项指标进行处理,剔除指标之间的内在关联性,提取主成分,然后利用主成份的综合评价功能对企业盈利能力进行综合评价,同时在此基础上分析综合评价指标的内在含义及比较方法 ...
时艳伟, 朱浣君
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Risk, Hazards &Crisis in Public Policy, Volume 15, Issue 2, Page 203-235, June 2024.Abstract Misinformation presents a challenge to democracies, particularly in times of crisis. One way in which misinformation is spread is through voice messages sent via messenger groups, which enable members to share information on a larger scale. Gaining user perspectives on digital misinformation interventions as countermeasure after detection is ...
Katrin Hartwig +2 more
wiley +1 more source
Shuitu Baochi Xuebao, 2016 选取黄土丘陵区岔巴沟流域不同位置和不同沟道级别的30条典型切沟为研究对象，基于三维激光扫描技术（LIDAR），建立了基于高分辨率DEM提取切沟形态特征的方法，对比分析了0.1 m与5 m 2种分辨率DEM提取切沟形态特征参数的差异，实现对低分辨率DEM提取的切沟形态特征参数向高分辨率尺度转化。结果表明：基于三维激光扫描技术获取的0.1 m高分辨率DEM提取到的切沟形态特征值与手工测量的切沟形态特征值之间无显著差异，三维激光扫描技术提取切沟长度、宽度、深度、表面积和体积分别是手工测量的94.0%，109 ...
吴红艳, 徐锡蒙
doaj
The Effect of Bispectrum Coupling Property on Fault Diagnosis [PDF]
, 2013 为了对双谱的耦合性质进行分析,同时利用三阶累积量和双谱对溢流阀进行故障诊断。由于双谱与三阶累积量相比,可以用来描述二次相位耦合,对比实验结果表明,故障的种类不同,其耦合信息对于这些故障判断的影响也不一样。实验中还通过二维小波在不同的方向上对故障信号和正常信号进行特征提取,然后将这些特征值输入支持向量机进行故障判别,实验结果表明,无论考虑耦合因素与否,这些故障信号在不同的频率部分与其正常状态的区分程度都不一样。In order to analyze the coupling properties of ...
吴文兵, 陈文芗, 黄宜坚
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Experimentally testing animal responses to prescribed fire size and severity
Conservation Biology, Volume 38, Issue 3, June 2024.Abstract Deserts are often highly biodiverse and provide important habitats for many threatened species. Fire is a dominant disturbance in deserts, and prescribed burning is increasingly being used by conservation managers and Indigenous peoples to mitigate the damaging effects of climate change, invasive plants, and land‐use change. The size, severity,
Tim S. Doherty +4 more
wiley +1 more source
Multi-channels Pulse Wave Recording and Processing System Based on LabVIEW [PDF]
, 2006 脉搏波是指随着心脏的间歇性收缩和舒张，血液压力脉动（或血流速度、血流量、血管壁的变形和振动）在血管系统中的传播。脉搏波虽然由心脏驱动，但是血液沿血管系统流动要经过很长的血管路径才能到达人体的各个部位，人体生理活动必然会对脉搏波产生影响。因此脉搏波携带了很多关于心血管系统和其他人体系统的生理信息。对于脉搏波的检测和处理具有重要的意义。如何科学量化脉搏波是生物医学工程尚未很好解决的问题。本文尝试用虚拟仪器技术解决这一问题。虚拟仪器技术是随着计算机技术的发展而出现并发展起来的新兴仪器技术。与传统仪器相比 ...
刘继伟
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