Results 11 to 20 of about 1,631,705 (163)
Dizhen xuebao, 2022 对Lg波衰减模型中建模误差的统计特征进行了系统研究，并建立了地壳二维Lg波衰减模型。由于Lg波振幅可能受到几何扩散函数的强烈影响，合理评估反演过程的误差对于能否使用最小二乘意义下的反演非常重要。通过在川滇及其邻近地区收集的建模误差样本，使用K-S数值检验方法、Q-Q图和正态分布图形检验方法对Lg波衰减层析成像反演的输入数据中建模误差的分布特征进行了统计分析。采用奇异值分解（SVD）和反投影方法，分别获得了川滇地区的QLg模型，定量计算模型的协方差矩阵和分辨率矩阵 ...
Yansong Hu +3 more
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2021年云南漾濞MS6.4地震动态应力对后续余震活动的触发作用
Dizhen xuebao, 2023 选取IRIS远震台站波形数据，反演了云南漾濞MS6.4地震震源破裂过程，计算了断层破裂在近场产生的动态库仑破裂应力变化，并讨论了主震对近场余震活动的动态应力触发作用。结果显示：动态库仑应力演化过程与震源破裂特征反演结果一致，其大小分布与地震序列分布的疏密程度也具有较好的相关性。主震产生的静态和动态库仑破裂应力均促进余震的发生，但相比静态应力，余震位于库仑破裂应力正值区域的比例提高了21%，余震与动态库仑应力变化的正负区域有更好的一致性，动态应力能更好地解释震后余震分布的空间特征。垂直于地震序列主干10 ...
Rong Liu +4 more
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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
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Asymptotic distribution of the product of ϕ-mixing sums(ϕ-混合序列部分和乘积的渐近正态性)
Zhejiang Daxue xuebao. Lixue ban, 2006 关于一列独立同分布正随机变量部分和乘积的渐近性性质，已得出了一系列结果.本文把独立性推广到相依随机变量的情形，对一列强平稳平方可积的正ϕ-混合序列{Xn，n≥ 1}进行讨论，若满足则其部分和的乘积渐近对数正态.
HUXing(胡星)
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Risk, Hazards &Crisis in Public Policy, Volume 17, Issue 4, December 2026.ABSTRACT Public communication campaigns on environmental issues rely on economic and ecological arguments, assuming that the recognition of messages is sufficient to produce adjustments in practices. Drought constitutes a specific case of this problem, as a creeping crisis: a slow‐onset hazard whose effects remain weakly visible in everyday life.
Sébastien Rouquette, Inès Bellahcene
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Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Microstructural characterization of Li0.32La0.56Fe0.01Ti0.94Sb0.06O3 (LLFeTSO) using AC‐TEM revealed that Fe3+/Sb3+ ion co‐doping induces the migration of lattice oxygen to grain boundaries (GBs), enhancing GB conductivity. However, the atomic arrangement at the GBs remains highly ordered and lacks sufficient cation vacancy carriers.
Binxuan Jiang +8 more
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, 1997 正态分布近似式的研究郑金成蔡淑惠王仁智郑永梅程灿东（厦门大学物理系，361005）正态分布是一种重要的概率分布，在许多情况下，简单的近似解析方程有助于问题的解决。通过将理论计算与数值模拟相结合的方法给出了一个较好的近似式。标准正态分布函数的形式为Φ（..
程灿东 +4 more
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Conservation Biology, Volume 40, Issue 4, August 2026.Abstract Knowledge of species distributions is essential for informing policies on nature conservation and restoration. However, updating them on a regular basis and doing so in a harmonized manner at the international level is difficult. The European Bird Census Council integrated national monitoring data covering 5 years to update farmland bird ...
Sergi Herrando +54 more
wiley +1 more source
, 2002 人们一般认为 ,合理的考试成绩的分布应当呈现正态分布或近似正态分布 ,而不应当呈现正偏态或负偏态分布。这有其合理性 ,但如果将适用范围任意扩大 ,则是错误的。成绩分布模型与四方面因素密切相关 :(1)学生群体的大小 ;(2 )学生群体和教师的能动作用 ;(3 )学生的素质和基础 ;(4 )成绩评定的标准。师生的教学活动可改变成绩分布模型 ,负偏态分布具有合理性 ...
张国才
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Uncovering correlates of decline and critical refuges for a threatened terrestrial mammal
Conservation Biology, Volume 40, Issue 4, August 2026.Abstract Globally, the geographic ranges of numerous species are contracting. Identifying spatiotemporal patterns of threat impact can illuminate why species decline in some parts of their range but persist in others. We developed a correlative approach to identify species’ response thresholds and locate ecological refuge areas associated with ...
Natalya M. Maitz +5 more
wiley +1 more source