Results 61 to 70 of about 8,663 (187)
Integrative Conservation, Volume 4, Issue 3, Page 362-380, September 2025.Occurrences of dust storms and long‐distance movement of dust across landscapes is constantly increasing in south Asia. This dust is expected to have profound impact on vegetation health and sustainability as dust may contribute to nutrient budgets of the forest ecosystems, while it could impart various stresses to the plants.
Shree P. Pandey +2 more
wiley +1 more source
Gaoya dianqi, 2019 文中提出了一种气体绝缘组合电器（gas insulated switchgear,GIS）超声波检测异常信号的时频特征计算与诊断方法。首先运用希尔伯特—黄变换（Hilbert-Huang transform,HHT）得到描述超声波信号包络线的时频特征的Hilbert幅值谱。在此基础上,给出了离散条件下Hilbert边际谱与平稳性指数的计算方法,分别表示信号中各频率成分的总强度和平稳性。然后将Hilbert边际谱与平稳性指数结合起来分析,可以直观读取信号的时频特征,进而推断出异常气室的故障原因 ...
管敏渊 +7 more
doaj
Research on Stochastic Resonance Based on RLGA and its Application to Underwater Acoustic Signal Detection [PDF]
, 2017 我国在水下通信领域方面正在持续地投入研究，其中一个方面是通信中信号的检测。信号经过水声信道后往往都会被来自船舶、海洋生物或者人为的大量噪声和海面折射反射、频率选择性衰弱引起的干扰淹没，变为微弱信号。而水声信号的检测技术不论在理论钻研还是实际工程甚至国防建设中都具有重要的意义和应用价值。因此，研究微弱信号的检测方法对水声通信的进步和发展很有必要。 一些传统的信号检测方法如匹配滤波、相干检测、时频分析等都采用抑制噪声的方法，往往都是在抑制噪声的同时，在频率结构或者时域幅值上也不同程度地损害了有用信号 ...
季舒瑶
core
A Review of UWB Radar Detection of Respiration and Heartbeat Signals in Different Scenarios [PDF]
Due to their many advantages, such as simple structure, low transmission power, strong penetration capability, high resolution, and high transmission speed, UWB (Ultra-WideBand) radars have been widely used for detecting life information in various ...
Bo ZHOU +6 more
core +1 more source
World Water Policy, Volume 11, Issue 3, Page 735-750, August 2025.ABSTRACT Ensuring the efficient operation of water supply facilities in the agro‐industrial sector is critical for sustainable resource management. The article streamlines the grouping of works performed during the operation of water supply facilities in six stages, differing in purpose, duration, and frequency of work.
Ekaterina Khmel +3 more
wiley +1 more source
Gaoya dianqi, 2001 应用小波均方谱对仿真局放信号进行了分析 ,得到了一个二维的时间—尺度等能量分布图。计算仿真结果与FFT频谱图相比较 ,表明小波均方谱具有良好的时频特性 ,即有多分辨率分析的能力 ...
赵中原, 邱毓昌, 王建生
doaj
Nondestructive inspection of carbon fiber reinforced plastic (CFRP) laminates using ultrasonic guided wave [PDF]
, 2017 碳纤维增强复合材料因其优良的物理性质，在现代工业，尤其是航空及船舶工业中得到了广泛的应用。该材料具有密度小、高比强、高比模、抗腐蚀、热膨胀系数小等一系列优点，被广泛用于制造飞机机身、机翼、发动机舱等结构。多层碳纤维增强复合板在生产或者使用过程中，可能会出现开裂，脱层和脱粘等现象，若不及时地检测出这些缺陷，将可能导致严重后果。目前，对多层碳纤维增强复合材料的检测方法主要有目视检查法、经典C扫描法，非线性超声法，光栅检测法，射线成像法等。 超声导波无损检测法近年来越来越受到重视 ...
吴秉正
core
International Journal of Applied Linguistics, Volume 35, Issue 3, Page 1134-1148, August 2025.ABSTRACT E‐books, powered by multimedia and interactive features, are widely used to support young children's language and literacy development. This study examines the relations of e‐book narration and bilingual parent–child talk to children's learning during shared reading. Data from 121 English learners in China and their parents were analyzed using
Dandan Yang +3 more
wiley +1 more source
Gaoya dianqi, 2019 为更有效在现场开展GIS局部放电检测,及时准确发现设备内部缺陷,特别是盆式绝缘子局部放电缺陷,文中研究了基于特高频时频定位分析的GIS局部放电综合定位方法。将多通道时延定位法和多通道小波时频分析法联合应用,通过局部放电特高频信号的时域和频谱变化特征,结合设备内部结构、装配工艺等情况,实现GIS局部放电综合精确定位。该方法在某500kV变电站220kV GIS带电检测中进行了应用,精确定位一处盆式绝缘子表面放电缺陷 ...
廖新征 +5 more
doaj
Journal of Linguistic Anthropology, Volume 35, Issue 2, August 2025.Abstract This article argues that social actors' media ideologies about digital interfaces are key to the enregisterment of online activities. Focusing on an online register emergent from user activities around Year, Hare, Affair (YHA)—a state‐aligned Chinese animation—I explore how different metadiscourses evaluate this register by entextualizing ...
Jiarui Sun
wiley +1 more source