Results 41 to 50 of about 36,110 (177)
500 kV罗平站主变加装中性点限流电抗器电磁暂态研究及设备选型
Gaoya dianqi, 2017 随着电网的发展,部分自耦变压器中压侧电抗常接近于零,导致变压器220 kV侧发生近区单相或两相接地时,故障穿越电流已接近甚至超过变压器可承受短路电流的极限值,为限制罗平站220 kV单相或两相短路电流水平、改善主变运行环境,拟在主变中性点加装限流电抗器。采用最新EMTPE程序,通过对主变接入限流电抗后短路电流水平、过电压及绝缘配合等电磁暂态特性研究,提出了500 kV罗平站主变中性点限流电抗器阻抗选取原则及限流效果、工频及操作过电压水平、流经主变中性点电抗器的工频稳态及暂态电流水平 ...
王典浪, 李东, 杨晓维, 皮天满
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Conservation Biology, EarlyView.Abstract Modeling species distributions in dynamic pelagic environments remains challenging, particularly for wide‐ranging and highly mobile species when there is limited guidance on model performance. This limitation constrains the effective use of species distribution models (SDMs) in marine conservation, where robust and transferable predictions are
E. Pasanisi +32 more
wiley +1 more source
Gaoya dianqi, 2017 接地模拟试验是实现接地网参数预测与接地特性分析的基本方法。一些接地材料如柔性石墨复合接地材料、离子接地体以及接地模块等在进行接地模拟试验时,其部分相似项并不能按照相似条件进行缩比,使得接地网原型的预测误差较大。针对此问题,笔者首先阐述了接地模拟试验的畸变相似模型,分析接地模拟试验中畸变相似项的来源,然后提出畸变系数与畸变项敏感度的概念。最后通过仿真实例和实际接地模拟试验,分析不同土壤电阻率与模型相似比条件下,接地模拟试验对接地体直径畸变项与接地体电阻率畸变项的敏感度 ...
高晓东 +5 more
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Genomics‐informed management of ex situ populations
Conservation Biology, EarlyView.Abstract The European Association of Zoos and Aquariums (EAZA) manages insurance populations for hundreds of species through its EAZA ex situ programs (EEPs). EEPs help safeguard against extinction in the wild and provide source populations for genetic rescue programs.
Cock van Oosterhout +8 more
wiley +1 more source
Optimizing biodiversity offsetting for habitat succession and colonization dynamics
Conservation Biology, EarlyView.Abstract Biodiversity offsetting aims to compensate for ecological losses from development through conservation and restoration. However, its long‐term outcomes under repeated impact–offset cycles remain uncertain. Using a conceptual forest succession model, we evaluated how offset outcomes are affected by interactions among compensation scale ...
Konstans Wells +4 more
wiley +1 more source
How endorser attributes influence conservation communication
Conservation Biology, EarlyView.Abstract Conservation communication often uses the celebrity endorsement strategy. However, robust evidence regarding its effectiveness is still limited. More importantly, practitioners do not have guidelines for selecting an ideal endorser because there is no clear consensus on what endorser attributes are most critical.
Xia He, Tien Ming Lee
wiley +1 more source
四川大学学报. 自然科学版, 1980 这是熟知的,两个相互等价的(即可经行列式为±1的整系数齐次线性变换互变的)实系数n元二次型f和g,对变元的所有整数值来说,表数相同(即凡能由f以整变元表出之数均可由型g以整变元表出,反之亦真).但是,相反的结论是否能够成立呢?亦即是否表数相同的二次型一定是等价的呢?这是基本而古老的问题.1830年,Legendre曾未加证明地断言,表数相同的二元恒定二次型必等价.1895年,Bauer曾就有相同行列式的真本原整系数恒定二元二次型这一特殊情形证明了Legendre的断言.
柯召, 郑德勋
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Learning Styles, Engagement and Anxiety in AI‐Mediated Writing: A Multimodal Feedback Study
International Journal of Applied Linguistics, EarlyView.ABSTRACT Artificial intelligence (AI) tools now permeate English academic writing. However, evidence on how feedback modalities align with student differences and with psychological mechanisms remains limited. Prior work often reduced learning styles to simple matches with delivery modes and treated learning engagement and writing anxiety as peripheral.
Yi Ren +3 more
wiley +1 more source
Zhongguo shiyan zhenduanxue, 2006 目的筛查与脑胶质瘤发病相关基因的单核苷酸多态性,进一步寻找胶质瘤易感基因。方法收集入院脑胶质瘤病人的血液。应用PCR扩增的方法对肿瘤相关的基因的特定片段进行扩增。利用变性高效液相色谱技术进行筛查。双向DNA直接测序,在GENBANK进行对比找到突变的碱基,并进行分析。结果变性高效液相色谱筛查后表明,在HLA-DMA基因中检测到了已知杂和性突变,并发现新的突变,HLA-DMA4EC杂合性缺失突变。结论变性高效液相色谱技术在筛查基因的SNPs方面显示了其快速、高通量和准确的特点。HLA ...
徐保锋 +4 more
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