Results 41 to 50 of about 907,556 (187)
Dianci bileiqi, 2018 电位分布及温度分布情况是对避雷器健康运行进行评价的重要指标,直接关系到整支避雷器的运行寿命,在无均压措施的情况下,将导致老化速度加快,甚至发生热崩溃。对避雷器的电位分布情况进行测试是对避雷器进行均压的首要条件,但传统检测手段均为基于有线光纤方式进行电位分布采集。本项目基于高性能AVR微处理器,便携式单片微型计算机采样,无线通信,同步采样分析等手段,成功研制了避雷器电位分布及温度分布无线检测系统。对避雷器电位分布及温度分布情况以无线同步方式进行测试,避免了测试现场繁琐的光纤布线 ...
李佳奇 +5 more
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How identity bias affects perceptions of conservation messages on social media
Conservation Biology, EarlyView.Abstract Public support is essential for conservation, as public opinion can influence decision‐making and policy. Therefore, understanding whether bias toward conservationists due to their identity (identity bias) affects their perceived credibility and support for their recommendations is important.
Lauren F. Rudd +4 more
wiley +1 more source
, 2008 通过小尺度生态监测与遥感数据分析获取塔里木河下游胡杨(PopuluseuphraticaOliv.)林现状信息,将胡杨个体对输水的响应实测数据和QuickBird影像信息进行对比和分析,"面"上宏观调查与"点"上典型研究相结合,集中对塔里木河下游阿拉干断面设立的100hm2长期监测样方内的4500棵胡杨树进行了详细的调查。研究表明:胡杨密度随着离河岸距离增加而呈现降低的规律。不同树高的胡杨也呈一定规律分布。树高小于3m的幼树主要分布在距河道50m范围内;树高3~9m之间的胡杨在研究区中占绝对优势 ...
Bodo Coenradie +5 more
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野生动物学报, 2010 根据2008～2009年实地考察研究结果,着重就该区2种有蹄类动物的分布、种群数量以及有关问题作概要性探讨。调查研究结果表明:（1）老虎台盘羊分布区盘羊平均密度=8.49/8=1.06只/km2,黑英山盘羊分布区盘羊平均密度=5.34/3=1.78只/km2。整个分布区盘羊种群数量1 488只,其中,老虎台分布区种群数量=480×1.06=509只,黑英山分布区种群数量=550×1.78=979只。（2）老虎台北山羊分布区北山羊平均密度=14.59/5=2.92只/km2 ...
阿布力米提·阿布都卡迪尔 +5 more
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Scientists’ warning on the global destruction of rock outcrop ecosystems
Conservation Biology, EarlyView.Abstract Rock outcrops are geological formations that harbor a highly specialized biota adapted to harsh environmental conditions that differ from their surrounding landscapes. They are globally distributed, especially in old, highly weathered landscapes, and can function as habitat islands containing high levels of endemism and distinct evolutionary ...
Luiza F. A. de Paula +19 more
wiley +1 more source
, 2015 沙冬青属(Ammopiptanthus Cheng f.) 隶属豆科(Leguminosae)蝶形花亚科(Papilionaceae)黄华族(Thermosideae)，是亚洲荒漠唯一的常绿阔叶灌木，属下有2个种：新疆沙冬青(Ammopiptanthus.nanus)和蒙古沙冬青(Ammopiptanthus.
刘美
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野生动物学报, 1994 貉貉（ＮｙｃｔｅｒｅｕｔｅｓＰｒｏｃｘｏｎｏｉｄｅｓＧｒａｙ）属于食肉目犬科。主要分布于亚洲东南部。在原苏联分布在黑龙江流域、乌苏里江流域向北分布到萨哈林半岛。在中国分布在东北、华北、华中、华南和西南地区一直延伸到越南北部。在日本和朝鲜半岛也有分布。...
高犁为
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Asymptotic distribution of the product of trimmed sums(一类截断部分和乘积的渐近正态性)
Zhejiang Daxue xuebao. Lixue ban, 2007 对于取值为正的独立同分布且平方可积的随机变量X1，X2，…且有连续的分布函数，令Mn = max{X1，X2, …，Xn}，对某固定常数a>0，令，截断和Tn（a）= Sn — Sn(a），在X的分布满足中尾分布的条件时，截断和Tn(a)的乘积为渐近对数正态.
ZOUHai-lian(邹海连) +1 more
doaj +1 more source
Conservation Biology, EarlyView.Abstract Ecological niche models (ENMs) are used to assess the abiotic preferences of species by linking their occurrences to the environmental conditions in which they live. We developed a fossil‐informed ENM framework that integrates mid‐Holocene and modern occurrences to test niche stability and reconstruct abiotic niche characteristics for four ...
Claire. M. Williams +3 more
wiley +1 more source
, 2009 以高分辨率遥感影像为本底数据的最新新疆地貌数据,能提高定量化地貌格局分析结果的准确性、客观性和科学性。本文利用地学统计和GIS空间分析方法,基于最新新疆地貌数据,定量化分析了地貌的分布特征、空间格局。结果表明:(1)大地貌单元中,平原地貌约占新疆总面积的1/3;(2)地势分级,中海拔地貌占绝对优势,约占全疆总面积1/2;(3)形态类型中,丘陵地貌在地势起伏中占主导地位,面积最大,主要分布在两大沙漠中,以沙丘形式分布;(4)基本地貌类型,中海拔丘陵最多,占总面积的21.417%;(5)成因类型中,流水 ...
柴慧霞, 程维明, 陈曦, 周成虎
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