Results 21 to 30 of about 13,597 (161)

Geographic risks to functional groups of mammals and birds from habitat loss in Mexico

open access: yesConservation Biology, EarlyView.
Abstract There is a need to quantify the impact of habitat loss due to anthropogenic factors on different aspects of biodiversity, such as functional trait diversity represented by functional groups (FGs). We developed a metric to assess the weighted risk of loss of habitat for 33 FGs of mammals and 36 FGs of birds in Mexico based on potential ...
Fernando Mayani‐Parás   +4 more
wiley   +1 more source

Ship detection optimization method in SAR imagery based on multi-feature weighting [PDF]

open access: yes, 2020
Aiming at the problem that the accuracy of traditional ship detection algorithms is not satisfying in complex scene with many false alarm targets,a ship detection optimization method in SAR imagery based on multi-feature weighting was proposed.Firstly ...
Guanghui WANG   +3 more
core   +1 more source

Attainment Pairing Effects on Cognitive Conflict in Technology‐enhanced EFL Cooperative Tasks

open access: yesInternational Journal of Applied Linguistics, EarlyView.
ABSTRACT This study examines how attainment pairing (high‐high versus high‐low versus low‐low attainment) impacts English as a Foreign Language (EFL) learner engagement during technology‐enhanced cooperative writing tasks. Seventy‐eight Chinese university learners formed 39 dyads (13 pairs per group) via Tencent Meeting.
Ying Liu, Allen Thurston
wiley   +1 more source

基于Matlab的ZnO压敏陶瓷几何效应研究

open access: yesDianci bileiqi, 2013
ZnO压敏陶瓷击穿场强E1mA由晶粒尺寸和单个晶界击穿电压两个因素共同决定,沿用之前提出的微观结构模型,在晶粒尺寸一定,晶界电压服从正态分布;晶界电压一定,晶粒尺寸服从正态分布;和晶粒尺寸、晶界电压都服从正态分布三种条件下,用Matlab分别模拟击穿场强随厚度的变化关系,结果表明ZnO压敏陶瓷击穿场强的几何效应主要来自晶粒尺寸和分布的影响。在此基础上,对初始厚度不同的试样进行击穿场强与厚度的关系模拟,从结果可以看到,无论是高击穿场强还是低击穿场强的试样,都存在几何效应。
鲍婕, 王政留, 李盛涛
doaj  

The Norm of the Learning-Disability Checklist for Elementary and Middle School Children (in Chinese) [PDF]

open access: yes, 2000
The Learning-Disabilities Checklist for Elementary and Middle School Children was administered to 1067 subjects in Shanghai. The data analyses brought us the following: 1) The mean and standard deviation of each variable of raw data; 2) There were ...
Chen, G. P., Shan, Y., Shao, Z. F.
core  

Underrepresentation of bats in Africa's protected areas

open access: yesConservation Biology, Volume 40, Issue 1, February 2026.
Abstract Biodiversity is severely threatened globally, with habitat loss and other human pressures accelerating species extinctions. Protected areas (PAs) are a critical conservation tool; however, their effectiveness in safeguarding many taxa, such as bats, remains unclear.
Cecilia Montauban   +9 more
wiley   +1 more source

棒形抗折试条的统计强度

open access: yesDianci bileiqi, 1980
本文研究了具有内部微观结构缺陷的瓷件在单轴向应力状态下强度的维布尔分布,给出δu=0情况下决定维布尔参数的一个图解方法。根据维布尔分布导出抗折瓷件在一定可靠性下极限应力下限值的计算公式,并比较了按维布尔分布和按正态分布计算的在相同可靠性下瓷件极限应力下限值的结果,结果表明按维布尔分布计算的下限位偏于安全。
马功勋, 刘长荣, 陶增炎
doaj  

正态分布近似式的研究 [PDF]

open access: yes, 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(..
王仁智   +4 more
core  

Genetic origins and climate‐induced erosion in economically important Asian walnuts

open access: yesConservation Biology, Volume 40, Issue 1, February 2026.
Abstract The global climate is undergoing unprecedented changes, posing significant threats to species persistence. However, the spatiotemporal impacts on genetic diversity remain poorly understood, hindering species conservation and management. Walnuts, generally referred to as Juglans regia and J. sigillata, are economically vital in Asia, but little
Peng‐Zhen Fan   +17 more
wiley   +1 more source

中国广东籍汉族人细胞色素 P4502E1 基因 5′ 侧翼区多态性

open access: yesZhongshan Daxue xuebao. Yixue kexue ban, 1999
目的: 探讨中国广东籍汉族人细胞色素 P4502E1 基因 5′侧翼区的多态性分布规律。 方法: 利用聚合酶链反应和 Rsa Ⅰ 、Pst Ⅰ限制性片段长度多态性( PCR-RFLP)技术对 82 名正常中国广东籍汉族人的细胞色素 P4502E1 基因 5′侧翼区的 多态性进行了检测。结果: 82名正常中国广东籍汉族人的细胞色素 P4502E1 基因 5′侧翼区 C1(Rsa Ⅰ +, Pst Ⅰ-)、C2(Rsa Ⅰ-, Pst Ⅰ +)等位基因频率分别为 0. 854, 0.
王 建 刘焯霖 黎锦如 邵 明 潘锡榜 陈 彪
doaj  

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