Results 21 to 30 of about 9,195 (119)
Gaoya dianqi, 2014 避雷器安装均压环能有效改善电阻片的电压承担率分布情况,均压环优化是以均压环管径、环径、罩入深度为优化自变量,最大电压承担率umax和均压环表面最大场强Emax为因变量,其中,umax为目标函数,Emax小于起晕场强为约束条件,均压环的最优参数难于求解但易于评估。为解决这一问题,采用微分进化算法结合有限元对750 kV避雷器均压环进行了优化计算,优化结果表明:优化后的避雷器电阻片电压承担率分布均匀程度改善明显,电阻片最大电压承担率umax由1.429降低至1.108,均压环表面最大场强由2.555 kV ...
姜志鹏 +5 more
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Assessing Closed Hydroponic Subsystems for Batavia Lettuce Growth Under Different Planting Densities
World Water Policy, Volume 11, Issue 2, Page 427-438, May 2025.ABSTRACT Hydroponic systems have the potential to be sustainable and alternative methods for food production that confer advantages of high production and better control of growth. However, only a few studies have focused on leafy vegetable growth in different subsystems and environmental variables.
Demet Çekin +6 more
wiley +1 more source
Dianci bileiqi, 2004 采用有限元法计算了加装均压环后的电场分布,结果表明,外加均压环的均压效果较好。均压环不但能改善电场分布,而且还有引弧、防止金具电晕、延缓芯棒老化等作用;最后探讨了均压环设置应该注意的问题。
陈树挺, 李日隆
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Hydraulic traits are coordinated but decoupled from carbon traits in herbaceous species
Functional Ecology, Volume 39, Issue 5, Page 1302-1317, May 2025.Read the free Plain Language Summary for this article on the Journal blog. Abstract Plant hydraulic traits primarily define the water regulation strategy, thus enabling a better understanding of vegetation structure, function and dynamics under varying hydro‐environments.
Ruike Huang +9 more
wiley +1 more source
Measuring the performance of Antarctic Treaty decision‐making
Conservation Biology, Volume 39, Issue 1, February 2025.Abstract Agreements reached at the Antarctic Treaty Consultative Meetings (ATCMs) are among the primary means for addressing Antarctic conservation and environmental protection issues. However, according to contemporary scholars, Antarctic Treaty decision‐making is becoming increasingly unresponsive to the rising environmental challenges in the region.
Natasha Blaize Gardiner +3 more
wiley +1 more source
Gaoya dianqi, 2012 为了提高有限元数值仿真计算方法在研究外绝缘设备电场分布的准确性,对均压环与绝缘子串电场进行仿真分析,并通过设置仿真参数来获得均压环管径和安装位置最佳尺寸的依据。针对湛江500 kV港城变电站均压环对玻璃绝缘子串放电现象,运用ANSOFT软件建立了500 kV交流杆塔上均压环与绝缘子串全三维模型,研究了均压环管径和安装位置对绝缘子串电场分布影响的规律,并通过对电场强度的仿真分析解释了均压环对绝缘子频繁放电的原因。仿真分析中研究了均压环管径及其安装位置对最大电场强度的影响 ...
王黎明 +3 more
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Postnatal outcome following fetal aortic valvuloplasty for critical aortic stenosis
Ultrasound in Obstetrics &Gynecology, Volume 64, Issue 3, Page 339-347, September 2024.ABSTRACT Objective To report our experience of fetal aortic valvuloplasty (FAV) for critical aortic stenosis (AS), with a focus on the postnatal evolution of the patients. Methods This was a retrospective study including all fetuses with critical AS which underwent FAV in a single center between January 2011 and June 2022.
R. Corroenne +14 more
wiley +1 more source
Gaoya dianqi, 2010 基于有限元数值仿真计算方法,建立了750 kV线路杆塔—导线—绝缘子的塔线三维电场仿真模型,研究优化750 kV复合绝缘子均压环的结构参数,并对均压环的均压效果进行了分析。计算结果表明,均压环可显著地改善绝缘子电场分布,高压端均压环表面的最大电场强度控制在20 kV/cm以下,可见电晕和无线电干扰试验的结果表明,高压端金具和均压环的起晕电压、无线电干扰水平均符合国家标准或规程要求,设计的均压环能够满足750 kV输电线路对复合绝缘子的使用要求。研究结果为750 kV输电线路外绝缘设计提供了有益的参考。
薄学微 +4 more
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基于矩量法和蝴蝶交配优化算法的甚低频发射天线顶线绝缘子均压环优化设计
Gaoya dianqi, 2020 针对甚低频发射天线顶线绝缘子串电压分布不均匀极易产生电晕的问题,采用矩量法（method ofmoments,MOM）研究了不同均压环管径、半径、抬高距以及绝缘子串配置位置对瓷支柱绝缘子串电压分布的影响,提出了一种应用矩量法和蝴蝶交配优化算法（butterfly mating optimization,BMO）协同优化顶线绝缘子串均压环的新方法。该方法首先建立顶线绝缘子串MOM天线优化模型;然后,提取仿真得到的分压和天线效率并计算目标函数;利用BMO迭代得到顶线绝缘子相对位置和均压环结构参数 ...
李斌 +4 more
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Gaoya dianqi, 2022 为减少多雷区用110 kV复合绝缘子雷击闪络次数，文中在110 kV复合绝缘子上加装悬浮中间均压环，研究其是否具有提升绝缘子耐雷水平的作用。试验测定了正负极性标准雷电冲击电压下的U50击穿电压，并使用高速摄影仪记录了放电过程。结合电场仿真，对得到的试验结果进行了讨论。结果显示，靠近正极性固定电位均压环布置的悬浮中间均压环具有提升绝缘子耐雷水平的作用，文中布置方式下最高提升约10%，并伴随有绕过均压环放电现象的发生。结果表明，采用悬浮中间均压环可以提高110 kV复合绝缘子耐雷水平 ...
卢明 +5 more
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