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Ageing simulation in health and social care education: A mixed methods systematic review 健康与社会关怀教育中的老龄化模拟:各类方法的系统性回顾

open access: yesJournal of Advanced Nursing, Volume 77, Issue 1, Page 23-46, January 2021., 2021
Abstract Aim To identify, evaluate and summarize evidence from qualitative, quantitative and mixed method studies conducted using age suits or other age simulation equipment, with health and social care students. Design Convergent segregated mixed method review design as outlined by the Johanna Briggs Institute.
Charlotte Eost‐Telling   +3 more
wiley   +1 more source

耦合地线在10kV架空线路中的应用研究

open access: yesGaoya dianqi, 2022
10 kV架空线路雷击跳闸率高,适用的防雷措施少。相比于架空地线,加装耦合地线的方法具有更好的适用性。文中分析了耦合地线在10 kV架空线路中的防雷机理、安装方式和适用性,认为在现有杆塔和线型条件下应仅加装1根耦合地线。利用ATP-EMTP分别搭建了单回三角形排列和双回直线排列方式的模型,分析了在直击雷和感应雷的作用下,耦合地线对10 kV架空裸导线和绝缘导线耐雷水平的影响。结果表明,对于裸导线,安装耦合地线后的反击耐雷水平和感应雷耐雷水平可提高36.2%~86.3%,雷击导线的耐雷水平可提高4%~13.
杨鑫   +5 more
doaj  

MOA和耦合地线配合使用的10 kV架空线路防雷方法

open access: yesDianci bileiqi, 2023
10 kV架空线路雷击跳闸率高,而可用的防雷措施较少,需对防雷方法进行综合应用以全面提高其耐雷水平。针对单独架设耦合地线无法提高其直击线路耐雷水平与耦合地线分段对线路感应雷耐雷水平的影响,本研究提出了一种综合性防雷方式,其方法是将MOA与耦合地线结合应用于10 kV架空配电线路。基于ATP-EMTP建立10 kV架空配电线路过电压模型,并考虑MOA允许通过的能量阈值。结果表明,MOA安装于10 kV架空配电线路的最高相和一边相,且在左右各1基安装时,在不需额外施加杆塔降阻措施下 ...
王延夫   +5 more
doaj  

金属管内同轴线耦合雷电电磁波特性的分析

open access: yesDianci bileiqi, 2023
针对雷电电磁波对具有金属管保护的架空同轴线造成传输信号干扰、设备损坏等问题,通过对同轴线耦合理论的分析,利用理论与试验相结合的方法,采用大型雷电冲击发生器模拟雷电流进行冲击试验,得到以下结论:随着冲击电流的增大,线缆上的耦合电压也越大,金属管内的同轴线耦合的电压总比管外的同轴线耦合电压更小,管径越大耦合电压更小,当管径达到一定尺寸时,可以将管内的同轴线耦合电压降低在1 V以下,有效保护线缆终端的电子设备不受到过电压而有损坏;由频谱图可知,耦合的最大振幅均集中在10 kHz ...
李祥超   +5 more
doaj  

雷击金属管管内线缆耦合特性分析

open access: yesDianci bileiqi, 2022
针对雷击金属管,金属管内部线缆耦合雷电电磁脉冲的问题,通过对电场理论及同轴耦合理论的分析,利用理论和试验相结合的方法,采用8/20μs波形雷电流注入3种不同半径的金属管,进行冲击耦合试验。试验结果表明:金属管内部同轴线缆耦合的电压峰值与能量随冲击电流的增大而增大;当管内线缆终端开路,耦合电压随金属管半径的增大而增大,终端屏蔽层接地与终端接50Ω的匹配电阻时,耦合电压随金属管半径的增大而减小。通过频谱分析可得:金属管内部同轴线缆终端开路以及终端接50Ω匹配电阻时,都是150 kHz~300 ...
李祥超   +4 more
doaj  

平行于雷电流通道同轴线耦合特性分析

open access: yesDianci bileiqi, 2021
针对舰船桅杆和高塔上的同轴线缆近距离耦合雷电电磁脉冲的问题,通过对同轴耦合理论的分析,建立同轴线缆近距离耦合雷电电磁脉冲的实验模型。采用组合波发生器模拟8/20μs雷电流波形,用长1 m直径16 mm的金属棒模拟雷电通道并作为辐射源,改变同轴线缆的长度以及距辐射源的距离进行试验。得出以下结论:同轴线缆近距离耦合雷电波时,线缆终端所得的电压波形仍为双指数波,在0.1~0.4μs有强烈的阻尼震荡,当线缆终端开路或接匹配电阻时,上升沿时间较短,约为1μs;当线缆终端屏蔽层接地时,上升沿时间变长,约为10μs ...
李祥超, 储蕾, 文巧莉, 欧阳文
doaj  

Policy Windows in an Authoritarian System: How Alignment, Leadership Signals, and Disasters Enabled Policy Entrepreneurship in China's Poverty Alleviation

open access: yesReview of Policy Research, Volume 43, Issue 4, July 2026.
ABSTRACT China's poverty alleviation campaign is significant. Over the past four decades, the number of people in China living below the international extreme‐poverty line fell by close to 800 million, accounting for nearly three‐quarters of the global reduction in extreme poverty.
Zhiqi Xu, Wil Hout
wiley   +1 more source

The Five‐Thread Model & Academic Policy Entrepreneurs: From the White Australia Policy to Multicultural Australia

open access: yesPolicy Studies Journal, Volume 54, Issue 2, May 2026.
ABSTRACT Why did Australia go from the White Australia Policy, which excluded non‐whites, to institutionalizing multiculturalism policy in the 1970s? This question defies traditional political ideologies of the major political parties, which had long supported the White Australia Policy. This article is a rare empirical demonstration of the Five‐Thread
Julius C. S. Mok
wiley   +1 more source

Herbivore species and patch heterogeneity modulate grazing‐induced shifts in soil nematode trophic structure and energy flux

open access: yesFunctional Ecology, Volume 40, Issue 1, Page 163-175, January 2026.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Grazing by large herbivores is a critical factor shaping grassland biodiversity and ecosystem functioning worldwide, yet its consequences for soil communities remain poorly understood.
Quanhui Ma   +12 more
wiley   +1 more source

耦合地线、避雷器对输电线路耐雷水平的影响分析

open access: yesDianci bileiqi, 2016
线路避雷器和耦合地线都能有效提高输电线路的反击耐雷水平。本文应用PSCAD仿真软件建立220 k V同塔双回输电线路的仿真模型,并进行雷击暂态分析,得到耦合地线以及线路避雷器对耐雷水平的影响,并确定了耦合地线的最佳架设位置以及线路避雷器的最佳安装个数,耦合地线最佳架设位置为下层横担与塔身交点处,单相安装时,避雷器应安装在中层,两相安装时,应都安装在中层。
李景丽   +3 more
doaj  

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