Results 41 to 50 of about 13,317 (119)
为了研究集群电缆敷设方式、回路间距、回路数以及排列方式对交流集群电缆直流载流量的影响,以10 kV交流配电网中广泛使用的三芯交联聚乙烯(XLPE)电缆为例,通过有限元仿真软件建立集群电缆的温度场和流场耦合仿真模型,得到了直埋敷设、排管敷设和沟槽敷设下集群电缆以双极式直流拓扑结构运行时的直流载流量、温度分布和流场分布。结果表明:随着回路间距和回路数的增大,集群电缆载流量的变化速率逐渐减小。直埋敷设下集群电缆之间的热场相互作用最大,而沟槽敷设下集群电缆之间的热场相互作用最小 ...
王启隆 +3 more
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ABSTRACT Objectives To compare the maternal hemodynamics of Chinese women at low and at high risk for preterm pre‐eclampsia (PE) and assess the differences in hemodynamic parameters between high‐risk women with or without prophylactic aspirin. Methods This was a prospective longitudinal case–control study of 857 Chinese women with a singleton pregnancy
X. Wang +11 more
wiley +1 more source
随着柔性直流输电技术的不断成熟,直流输电变得越发普及,而高压直流断路器作为直流输电系统的关键部分,其重要性不言而喻。针对现有高压直流断路器存在故障时短路电流大、分断速度慢、避雷器吸收能量过高等问题,提出了一种具有限流能力的新型高压直流断路器拓扑,该拓扑在传统直流断路器换流支路基础上增加了H型桥限流部分,利用平波电抗器与限流部分共同限流,可以显著降低故障时电流的上升速率与峰值。文中详细说明了新型拓扑的基本工作原理,对故障分断过程进行理论分析并给出相关参数的影响关系及选取依据,通过搭建基于Pscad ...
章宝歌, 荣耀, 张振
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Beyond Motivation: Modeling the Predictive Role of L2 Pride in Informal Digital Learning of English
ABSTRACT This study investigates the role of second language (L2) pride—an understudied affective factor—in shaping learners’ language learning motivation and involvement with informal digital learning of English (IDLE). Drawing on questionnaire data from 1388 Chinese university EFL students, the study employs structural equation modeling to examine ...
Minlin Minny Zou +3 more
wiley +1 more source
Clip Voice: Misogyny and the Renegotiation of a Gendered Vocal Style in Chinese Digital Discourse
ABSTRACT The participatory culture of social media allows women's voices to be heard but also parodied and policed. On Chinese social media platforms, where performers rapidly adopt and transform vocal trends for engagement, discourse on gendered vocal styles has proliferated.
Zichuan Yu, Rebecca Lurie Starr
wiley +1 more source
短路电流中带有直流分量时的交流高压断路器燃弧时间差的概率分布特性
根据三相短路电流中带有直流分量时的开断过程,提出了分析和计算燃弧时间差的方法,据此求出了中性点接地与不接地系统的短路电流中带有直流分量时,燃弧时间差的分布规律.本文也列出了开断电流波形与电弧能量的关系.
曹荣江, 顾霓鸿, 盛勇
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This study provides an innovation to address the challenge in accessibility to samples and genetic markers in Snow leopard conservation genetic studies. We performed next‐generation sequencing (NGS) on 19 fecal samples obtained from the eastern Qinghai‐Tibet Plateau, and successfully assembled 17 complete mitogenome sequences (~16,720 bp) and ...
Chen Cheng +7 more
wiley +1 more source
We discussed the key assumptions of Distance sampling that were considered hard to meet in mountainous terrains and potential solutions for them. Our survey yielded comparable estimates from distance sampling and double‐observer survey, although the confidence interval from distance sampling was broader.
Lingyun Xiao +4 more
wiley +1 more source
高压直流断路器开断直流电路后,系统电感中的一部分能量必须消耗在能量吸收装置中,这部分能量与直流输电线路的参数、故障点的位置以及开断电流的大小有关,本文利用电磁暂态过程计算程序对此进行了计算。
张节容, 徐国政, 沈力, 吉嘉琴
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文中对一类传统的直流滤波傅里叶算法的误差进行了分析,并在研究的基础上提出了一种新的直流滤波傅里叶算法。首先分析此类传统的直流滤波傅里叶算法如何修正带有直流衰减分量的短路电流采样值,分析修正采样值的过程中误差的变化,然后利用MATLAB仿真计算了此类算法的误差规律,最后提出一种兼顾运算量和计算精度的直流滤波傅里叶算法。
崔建, 陈丽安, 田洪, 张朝科
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