Results 31 to 40 of about 7,369 (142)
Genomic responses to increased temperature and pollinator selection in Brassica rapa L.
Summary Rapid environmental change reshapes both abiotic stress and biotic interactions, yet it remains unclear how these combined forces structure plants' genomic adaptation. In particular, the joint influence of temperature and pollinator identity, two ecological axes undergoing simultaneous global shifts, has rarely been quantified at genomic ...
Yanqian Ding, Florian P. Schiestl
wiley +1 more source
Impacts of Human Development on Wildlife Use of Corridors in Botswana 人类开发对博茨瓦纳野生动物廊道利用的影响
This study examined the effect of landscape‐scale human impact on wildlife in Botswana. We examined how species use wildlife corridors in two different human‐dominated landscapes. We identified differences in temporal overlap between wildlife and humans across both landscapes, which is fundamental to consider in both current and future conservation ...
Tempe S. F. Adams +3 more
wiley +1 more source
针对利用阶跃响应法测试光电探测元件频率响应时存在无法获得相频特性的问题,文章通过Multisim软件建立了与实际器件参数一致的等效电路,根据相频特性中相位差与时间差之间的关系,提出了一种同时测量幅频特性和相频特性的频率响应测量方法,仿真测量的幅频特性结果与传统阶跃响应法的测量结果一致。光电二极管的相频特性对高速接收系统的设计具有重要影响。
李子强, 吕辉, 杨涛
doaj
ABSTRACT The transformative potential of gallium nitride high electron mobility transistors (GaN HEMTs) in advancing carbon‐neutral power systems remains bottlenecked by contact resistance (Rc) at the metal–semiconductor (M‐S) interface, a critical determinant of switching losses and frequency response.
Ji‐Zhou Zhang +8 more
wiley +1 more source
雷电流可分解为不同的频率分量,目前对于雷电流各频域范围与冲击响应电压之间的对应关系还缺乏相应的研究。在CDEGS中建立土壤电阻率500Ω·m下的100 m长水平接地体模型,利用MATLAB计算研究2.6/50μs雷电流中各频域范围对100 m长水平接地体的冲击电压幅值及幅值时间的影响,研究了将雷电流通过傅里叶变换分解为一系列的离散频率,计算接地极在各频率下的响应电压,再通过傅里叶反变换合成得到雷电流冲击响应电压波形的方法。并通过与CDEGS仿真的雷电流冲击响应电压波形对比分析 ...
马御棠 +6 more
doaj
ABSTRACT Regulating negative parameters of metacomposites is mainly limited by their unclear mechanisms, which affects their practical applications in new sensing, communication, electromagnetic (EM) protection and other fields. This work proposes a dual‐functional competitive design strategy based on the waste corncob‐derived carbon/polyaniline ...
Qiuyun Yang +4 more
wiley +1 more source
Finding floral and faunal species richness optima among active fire regimes
Abstract Changing fire regimes have important implications for biodiversity and challenge traditional conservation approaches that rely on historical conditions as proxies for ecological integrity. This historical‐centric approach becomes increasingly tenuous under climate change, necessitating direct tests of environmental impacts on biodiversity.
Zachary L. Steel +8 more
wiley +1 more source
目前采用频率响应法诊断变压器绕组变形的应用相当广泛,但是在实际测量中,其测试结果会受到诸多因素的影响而失真,若不能准确识别这些影响因素,测试结果的可比性将大大降低,从而给测试结果的分析、判断带来困难甚至错误。笔者结合频率响应法检测技术在天水电网的应用情况,总结了现场由于各种影响因素造成的绕组频率响应曲线异常的实例并将其逐一归类,为今后判断变压器绕组变形提供依据。
曹小龙 +6 more
doaj
Abstract Forest cover is positively associated with fish biomass and fisheries yield in the Amazon River floodplain, and many species enter flooded forests to feed, spawn, or seek refuge from predation. Floating macrophyte beds, known as floating meadows, in Amazon floodplains support high fish diversity and serve as nursery habitat for many fishes of ...
Sam Grinstead +6 more
wiley +1 more source
有限长脉冲响应(FIR)数字滤波器可以使用频率取样结构来实现,但是,现有文献中讨论的频率取样结构只是对于窄带滤波器才比较有效,本文提出一种新的频率取样结构,这种结构能有效地用于宽带数字滤波器。一 引言设有限长脉冲响应(FIR)数字滤波器的脉冲响应序列h(n)的长度为N ...
林道发
doaj

