Results 91 to 100 of about 38,620 (164)
Dianci bileiqi, 2019 介绍了双极性窄脉冲（narrow bipolar events,简写NBEs）自动识别的基本方法,通过对双极性窄脉冲的放电特征的统计分析,设计了自动识别的试验方案。对VHF辐射波形和闪电快电场波形中的NBE进行了自动识别方法实验验证。首先对闪电数据进行人工识别,识别出96例NBEs,对其中19例NBEs的11个放电参数进行参量统计和研究分析,根据统计结果选取高频幅度比等9个参数作为NBEs识别判据,对混杂在常规闪电放电中的NBEs进行程序自动识别。成功识别出双极性窄脉冲67例,未识别出10例 ...
王拓, 孙昊, 王彦辉, 张其林
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Journal of Animal Ecology, Volume 95, Issue 7, Page 1178-1193, July 2026.This population‐comparative study reveals that male and female parents respond differently to social and ecological conditions. This sex‐specific responsive strategy is related to the incongruent parental care systems across populations in Chinese penduline tits.
Jia Zheng +5 more
wiley +1 more source
Methods in Ecology and Evolution, Volume 17, Issue 7, Page 2123-2134, July 2026.Abstract Elliptic Fourier analysis (EFA) is often employed in geometric morphometrics (GM), but the normalization of elliptic Fourier descriptor (EFD) has persistently posed challenges for obtaining unique and comparable results, especially in the application of outline‐based GM methods, which limits the implementation in automated analysis of numerous,
Hui Wu +6 more
wiley +1 more source
野生动物学报, 2012 由于火烈鸟在外观上雌雄极为相似,很难用常规方法对其性别进行鉴定。本试验首次确立了利用PCR技术对火烈鸟性别进行鉴定的分子标记方法。从火烈鸟血液中提取总基因组DNA,针对性染色体上的CHD基因和EE0.6序列,筛选了4对引物进行特异性扩增,其中3对引物组合成2个组（A/B和B/C）进行多重PCR。结果表明,3组引物都在雄性个体中扩增出1条片段,在雌性中扩增出2条片段;待测群体中雄性个体11只,雌性个体6只。经检验,利用3组引物都能准确鉴定火烈鸟性别,为该物种在分子水平上的性别鉴定奠定了基础。
李文斌 +5 more
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The Photogrammetric Record, Volume 41, Issue 195, July/September 2026.Tri‐stereoscopic PeruSat‐1 imagery enables the simultaneous generation of 0.70 m‐resolution topography and spatially distributed Manning roughness maps, achieving 0.434 m vertical accuracy. Integrated into HEC‐RAS, these products provide consistent, high‐resolution inputs that improve hydraulic modelling and flood risk assessment in data‐scarce river ...
Jorge L. Miranda‐Pita +3 more
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Gaoya dianqi, 2018 电力设备中,不同类型的放电因放电功率、能量的差异对设备绝缘的损害能力存在差异,即对绝缘的危害程度不同,确定局部放电类型是放电危险度评估的基础。文中对典型缺陷条件下的局部放电谱图提取了基本参量及统计参量等多种特征指纹;为了降低识别参量的维度,定义了特征向量可分性评估准则,并使用浮动前向搜索算法选取了可分性最优的9组特征参量;分别使用主成分分析、线性可分性分析、核主成分分析及通用可分性分析4种方法将特征向量降为2维,结果表明,使用通用可分性分析降维后特征参量可分性最优。之后,提出了多算法联合的模式识别分类器,
王世强 +4 more
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Review of Policy Research, Volume 43, Issue 4, July 2026.ABSTRACT The accelerated digitalisation of society has amplified cybersecurity threats and revealed their cross‐sectoral nature. Yet, the policy instruments used to address these challenges remain insufficiently examined. This study conducts a scoping review of 980 academic articles (2007–2024) and applies Hood's NATO framework (Nodality, Authority ...
Benedetta Cotta, Maria Stella Righettini
wiley +1 more source
带并联电抗器的交流特高压输电线路单相自适应重合闸故障识别方法
Gaoya dianqi, 2013 为使单相自适应重合闸避免重合于永久性故障,需对线路故障类型进行准确的识别。笔者针对带并联电抗器的交流特高压输电线路,计算瞬时性故障与永久性故障时中性点小电抗电压与故障线路端电压幅值比,分析发现,两种故障情况下其比值明显不同,因此利用中性点小电抗与故障线路端电压幅值比为判据,可准确判别瞬时性与永久性故障。大量ATP/EMTP仿真结果表明,该方法可以有效识别不同故障类型,且判别方法简单可靠性高。
何柏娜, 赵云伟, 林鹤云
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Zhongguo shiyan zhenduanxue, 1997 为探讨血清和尿中假尿苷（ψ）对恶性肿瘤的诊断价值，用高效液相色谱法测定了５０例正常人、６８例鼻咽癌、４２例原发性肝癌、４１例肺癌、２４例急性白血病和相应部位良性疾病患者血清和尿中ψ的含量。正常人的血清和尿中ψ水平分别为３．０８±０．４９ｎｍｏｌ／ｍｌ、２１．６±２．９ｎｍｏｌ／μｍｏｌ肌酐。鼻咽癌、原发性肝癌、肺癌、急性白血病患者血清ψ分别为４．３２±１．４０、６．７４±３．４４、５．１０±１．９２、６．００±２．０１ｎｍｏｌ／ｍｌ，尿ψ分别为２８．６±６．２、３６．９±１１．７、３１．９±８．３、３５．
江丽 +4 more
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四川大学学报. 自然科学版, 2006 利用独立分量分析提取字符特征,以信息理论中负熵作为估计输出分量之间独立性的目标函数,并在此基础上对待识别字符进行重建,通过对重建模型的误差分析进行字符识别.对3000个车牌字符的识别实验,取得了较高的识别率,证明其算法的有效性和鲁棒性.
李旻 +4 more
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