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Lg波衰减模型中建模误差的定量评估

open access: yesDizhen 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
doaj   +1 more source

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

open access: yesDizhen 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
doaj   +1 more source

Asymptotic distribution of the product of trimmed sums(一类截断部分和乘积的渐近正态性)

open access: yesZhejiang 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

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)

open access: yesZhejiang 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)
doaj   +1 more source

Structural Reliability Estimates of Strength Variable in the Normal Distribution with Multiple Stresses of Independent(服从正态分布的强度变量在多个独立应力作用下的结构可靠性估计)

open access: yesZhejiang Daxue xuebao. Lixue ban, 1999
本文讨论了服从正态分布的强度变量在(分布不一定相同的)多个独立应力作用下的结构可靠性估计.在假设应力参数已知,强度参数部分未知或全部未知的条件下,给出了结构可靠度的点估计和置信下限.
XuMingmin(徐明民)   +1 more
doaj   +1 more source

Life Stage‐Specific Genetic Diversity and Landscape Characteristics Collectively Influence Genetic Recovery in Pometia pinnata Population 生活史阶段特异的遗传多样性与景观特征对番龙眼种群遗传恢复的协同影响

open access: yesIntegrative Conservation, EarlyView.
Pometia pinnata demonstrated life‐stage‐specific genetic responses to landscape features, with asymmetric gene flow patterns and population recovery following historical bottlenecks, revealing complex topographic and demographic influences on forest genetic structure.
Madhuparna Chatterjee   +5 more
wiley   +1 more source

Sun Bear Ecology and Conservation: Multiscale Habitat Associations in Southeast Asia 马来熊的生态与保护:东南亚地区的多尺度生境关联研究

open access: yesIntegrative Conservation, EarlyView.
We collated detections of the sun bear from new and previously published camera trap studies across its range. We then analysed these detections at two different spatial scales to assess the habitat associations and diel activity of this species. We found that the sun bear is tolerant to moderate habitat disturbances. ABSTRACT Degraded tropical forests,
Alexander Hendry   +5 more
wiley   +1 more source

Justice in coexistence: Pastoralism and large carnivores on the Qinghai‐Tibet Plateau

open access: yesPeople and Nature, EarlyView.
Abstract The conflict between livestock husbandry and large carnivore conservation presents significant challenges in grassland ecosystems worldwide. Achieving sustainable coexistence among herders, livestock and large carnivores requires reconciling diverse perspectives and interests through equitable, inclusive and fair processes that address both ...
Yufang Gao, Yue Yu
wiley   +1 more source

大宁河流域坡度与坡向对土地利用/覆盖变化的影响

open access: yesShuitu Baochi Xuebao, 2004
通过解译同源不同时期卫星遥感影像数据,应用GIS对空间数据和属性数据的有效管理和分析,阐述了大宁河流域土地利用/覆盖随坡度和坡向的分布规律以及坡度和坡向的变化对土地利用/覆盖动态变化度和综合土地利用动态变化度的影响,分析了社会经济和政治因素对流域内土地利用/覆盖动态变化的正向和负向的驱动力作用。研究表明,大宁河流域内人类活动主要集中在坡度较低的区域,受社会因素的影响,人类活动正向较陡坡区域发展,陡坡耕地和极陡坡耕地在流域内分布过多,森林面积分布过少,从而对环境造成了负面影响。
周爱霞 马泽忠 周万村
doaj   +2 more sources

Jellyfish blooms restructure plankton dynamics and trophic linkages in coastal waters

open access: yesFunctional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Jellyfish blooms are increasing globally in frequency and intensity, introducing complex ecological interactions, yet the mechanisms by which they alter ecosystem structure remain poorly characterized due to a lack of sustained field observations.
Pengpeng Wang   +4 more
wiley   +1 more source

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