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A Framework of Nature Education 自然教育的框架
Integrative Conservation, Volume 4, Issue 1, Page 38-44, March 2025.The framework of nature education provides guidance for educators in designing and improving their programs. Principles within this framework, categorized into foundational concepts, engagement strategies, and desired outcomes, offer a shared language for discussing nature education, and emphasize the role of nature education in human well‐being and ...
Alex Kudryavtsev
wiley +1 more source
On the precursor of the flux and path variation of Kuroshio in the East China Sea [PDF]
, 2016 本文利用区域海洋模式系统（RegionalOceanModelingSystem，ROMS），针对东中国海海域（渤海、黄海和东海），建立了高分辨率三维斜压海洋模型，其长期模拟结果成功再现了东中国海和西太平洋暖池部分海域的主要海洋环境特征，及黑潮月、年际和年代际的变化。在此基础上，通过大量敏感性试验，研究了在7天尺度上可以导致PN断面处黑潮流量发生异常变化的前期征兆以及吐噶喇海峡处黑潮路径变异的前期征兆；另外，基于模式模拟结果、沿海验潮站水文数据等资料，本文也分析了东中国海海平面演变的空间差异 ...
吕观通
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Routine 36‐week scan: diagnosis and outcome of abnormal fetal presentation
Ultrasound in Obstetrics &Gynecology, Volume 65, Issue 2, Page 154-162, February 2025.ABSTRACT Objectives First, to report the incidence of non‐cephalic presentation at a routine 36‐week ultrasound scan, the uptake and success of external cephalic version (ECV) and the incidence of spontaneous rotation from non‐cephalic to cephalic presentation.
M. Fitiri +5 more
wiley +1 more source
Model Based or Data Based Approaches for the Identification of Structural Nonlinearity with Limited Output Measurements [PDF]
, 2014 由于自然或人为的因素，非线性广泛的存在于实际结构中，包括为抵抗地震作用在结构基底中设置的橡胶隔震支座的非线性行为，以及建筑结构在长期的损伤累积中所产生的非线性行为。由此可见，非线性的识别研究对于结构的安全评估与损伤诊断起着非常重要的作用。故本文在总结了目前国内外非线性结构识别的研究进展的基础上，研究部分观测结构响应下，结构非线性特性识别的新方法。 论文首先研究基础隔震结构中橡胶隔震支座的非线性特性的识别方法。当隔震支座的非线性特征具有合适的数学物理模型时 ...
何明煜
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Jianzhu Gangjiegou Jinzhan, 2006 本文回顾了近代非线性薄壳稳定理论的发展历史,认为薄壳稳定理论的研究大体经历了三个阶段:第一阶段为针对完善结构的线性弹性理论;第二阶段为考虑结构几何缺陷的非线性弹性理论;第三阶段为考虑实际材料性能的非线性弹塑性理论。目前正在进入第四阶段,即开始考虑结构物理缺陷的影响。最新的三个主要研究方向是:1)非线性薄壳有限元分析方法;2)材料局部损伤过程对薄壳稳定性的影响;3)带裂纹薄壳的稳定性分析。文中分别就这三个方向的研究现状进行了调查分析,并对今后的研究趋势进行了展望。
周利, 黄义
doaj
Politics &Policy, Volume 53, Issue 1, February 2025.ABSTRACT This article argues that the European biometric ID installations and securitization practices at West African borders harm African migrants and compromise the security goals of Europe and Africa. Using Niger's experience, I contend that migrants' poor adaption to the biometric border processes is closely connected to their identity conflicts ...
Victor Chidubem Iwuoha
wiley +1 more source
China's State‐Capitalist Development Model: Is It Viable in Ghana?
Politics &Policy, Volume 53, Issue 1, February 2025.ABSTRACT The relative success of China's state‐capitalist model has reignited debates about state centrality in economic growth and the feasibility of replicating the model in developing countries. Shedding new light on the ongoing dialogue, this study examines the viability of China's model in Ghana and applies the property rights, public choice, and ...
Daniel Abankwa
wiley +1 more source
Robust control of SVC: A new adaptive backstepping method [PDF]
, 2006 Dimirovski, Georgi M. (Dogus Author)A new extended adaptive backstepping algorithm for general nonlinear systems in parametric feedback form is proposed.
Dimirovski, Georgi M. +2 more
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Jixie chuandong, 2015 由于齿轮传动存在间隙、摩擦以及时变刚度,其动力学特性具有强烈的非线性。当齿轮发生故障时,如点蚀、剥落以及断齿,振动信号往往伴随有超谐波、次谐波等非线性特征,给齿轮故障诊断带来一定困难,因此有必要研究齿轮不同故障程度时的非线性振动机理。通过应用傅里叶级数来描述齿轮时变刚度,一定程度上避免了分段函数刚度突变问题;通过引入齿轮故障程度因子来描述齿轮故障程度,建立了齿轮故障程度的非线性动力学模型;并搭建齿轮故障演化实验台进行相关实验。仿真和实验结果表明,在一定摩擦因数以及转速时 ...
苏勋文, 王少萍
doaj +1 more source
Guangtongxin yanjiu, 2002 通信距离的延长和 WDM通道数的增加使光纤非线性效应日益显著 ,如何准确地测量非线性系数的大小成了人们关注的问题 .文章介绍了几种非线性系数的测量方法 ,并对它们的优缺点进行了较全面的分析和比较 .
华颖, 陈永诗
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