Results 31 to 40 of about 2,843 (132)
500kV避雷器保护距离试验及对热备用断路器距离保护效果分析
Dianci bileiqi, 2015 首次开展了对500 kV避雷器保护距离的模拟试验,得出了避雷器对被保护设备的保护效果随保护距离的增大而减小的结论,并根据试验结果拟合了关系曲线。同时,考虑到变电站或换流站遭受多次雷击后受避雷器保护的断路器处于热备用状态的情况,进行了断路器热备用状态下避雷器对其保护范围的计算分析,并选取地处雷电频繁区贵州的兴仁换流站为例,仿真分析了当站内交流侧被保护断路器处于热备用状态下,不同雷击下避雷器对其的保护范围及保护效果,得出了避雷器保护范围受不同因素影响的具体情况。
邱慧敏
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On the normative roles of biodiversity and naturalness in conservation
Conservation Biology, Volume 39, Issue 5, October 2025.Abstract Nature is an opaque concept. Consequently, the term biodiversity conservation has replaced nature conservation in most conservation contexts. We review the conceptual indeterminacies that plague the terms nature and natural but then show that comparable difficulties plague biodiversity.
David Saltz, Shlomo Cohen
wiley +1 more source
Dianci bileiqi, 2018 针对电涌保护器（SPD）动作时可能对负载电压起到抑制作用而导致SPD无法达到预期的有效性保护的问题,本文通过混合波发生器模拟雷电流,对负载分别为阻性、容性时,特性阻抗值相同、长度不同的RVVP电缆做冲击试验,研究负载与RVVP电缆特性阻抗匹配关系及波电缆中的折射反射现象,分析不同长度RVVP电缆与不同特性负载的关系。得出当负载为阻性时,电涌保护器的有效保护距离与电阻值呈负相关;当负载为容性时,电涌保护器的有效保护距离与电容值呈正相关。
李顺昕, 朱正甲, 李岩峰
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A global indicator of species recovery
Conservation Biology, Volume 39, Issue 5, October 2025.Abstract Monitoring progress toward meeting global biodiversity goals involves several indicators, including, at the species level, the International Union for Conservation of Nature (IUCN) Red List Index (RLI) and the Living Planet Index (LPI). However, at present, there is no indicator specifically for tracking species recovery, despite this being ...
H. Resit Akçakaya +4 more
wiley +1 more source
Dianci bileiqi, 2018 配电线路遭受雷击后,沿线路侵入的雷电浪涌十分容易导致变压器低压侧负载设备的损坏,有必要对此防护进行研究。利用PSCAD软件搭建配电系统模型,采用高频变压器模型与IEEE氧化锌压敏电阻模型,分析变压器低压侧负载性质对负载端过电压的影响,讨论不同负载下变压器低压侧电涌保护器对应的有效保护距离。分析结果表明:负载端过电压波形存在明显的振荡,阻性负载端过电压衰减较快,感性负载和容性负载端过电压持续时间较长。阻性负载或感性负载幅值较小时,负载端过电压随着SPD与负载间连接电缆长度的增加而减小;阻性负载幅值较大时 ...
杨剑锋 +4 more
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Earth Science-Journal of China University of Geosciences, 2021 磊 任, 颖 朱, 天麟 崔
semanticscholar +1 more source
Integrative Conservation, Volume 4, Issue 3, Page 277-286, September 2025.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
Gaoya dianqi, 2016 鹰潭供电公司220 kV月铜线发生的两起雷击跳闸故障,故障相均安装了线路避雷器,因此,供电公司对线路避雷器的保护效果产生了疑虑。为深入验证线路避雷器的保护效果,避免类似事件的再次发生,国网江西省某电力科学研究院通过开展线路避雷器雷电冲击50%放电电压试验和工频湿耐受电压试验对避雷器间隙距离进行了深入研究,得到了不同间隙距离线路避雷器与不同绝缘子串的配合裕度,在此基础上给出220 kV线路避雷器间隙距离推荐值（840±10）mm,可以同时满足保护可靠性与运行安全性的要求。
邹建章, 张宇, 胡京, 李阳林
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Integrative Conservation, Volume 4, Issue 3, Page 302-309, September 2025.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
野生动物学报, 2021 2016—2018年秋季（9—11月），以定点观测方式布设225个观察点，对吉林向海国家级自然保护区的鸟类进行调查，以ArcGIS 103通过导入坐标点的方法将观察点落入3 km×3 km网格中，通过对Landsat 8影像进行监督分类以及对数字高程图（DEM）进行数据提取得到生境因子信息，然后利用ArcGIS 103获取各网格的生境因子信息，包括距耕地距离、距林地距离、距水体距离、海拔、坡度、坡向等。利用Excel以及香农-维纳指数、均匀性指数 ...
杨飞飞 1# 利世锋 1 +1 more
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