Results 31 to 40 of about 1,340,291 (192)
Gaoya dianqi, 2012 由于绝缘材料的电阻率具有非线性和各向异性,故在计算换流变压器阀侧绕组直流电场时需要考虑到绝缘材料的非线性和正交各向异性。笔者采用ANSYS二次开发技术,计算了在考虑绝缘材料电阻率随场强和温度变化情况下的非线性直流电场及非线性各向异性直流电场。计算结果表明,在考虑绝缘材料电阻率非线性和各向异性的情况下,电场分布与不考虑这些条件下的分布有很大的不同。因此,换流变压器阀侧绕组的直流电场应该按非线性各向异性场计算。
李晓辉 +3 more
doaj
Ultrasound in Obstetrics &Gynecology, Volume 68, Issue 2, Page 256-269, August 2026.ABSTRACT Objectives The primary aims of this study were to validate externally the diagnostic performance of the Assessment of Different NEoplasias in the adneXa (ADNEX) model for distinguishing between malignant and benign adnexal masses, when used by non‐expert ultrasound examiners in general gynecological settings with a low prevalence of ovarian ...
I. M. Dueholm Hjorth +11 more
wiley +1 more source
, 1979 星系密度波理论成功地解释了螺旋结构的缠卷困难。为了克服有限群速度引起的维持困难,人们研究了各种线性波的不稳定增长模式解。线性波的不稳定性分析只能适用于短的时间发展,所以应该进一步讨论非线性密度波的稳定性。徐遐生等用星系激波方程计算恒星的非线性密度波时发现,解极敏感地依赖于初值的选择,可能在物理上不稳定 ...
王联, 胡文瑞, 王慕秋, 秦元勋
core +2 more sources
四川大学学报. 自然科学版, 1998 ＫＴｉＯＡｓＯ４（ＫＴＡ）晶体是一种新型的性能优良的铁电晶体，它的电光效应和非线性光学效应尤为突出，使得它在光电子技术及非线性光学领域有一系列重要应用［１］．ＫＴＡ与另一种已知的性能出众的非线性光学材料ＫＴｉＯＰＯ４（ＫＴＰ）相比，具有更高的非线性光...
廖宇, 焦志峰, 唐林昌, 徐晓非
doaj
Changes in the transformative potential of action proposals in Finnish Red Lists from 1986 to 2019
Conservation Biology, Volume 40, Issue 4, August 2026.Abstract Red lists provide critical knowledge regarding biodiversity decline, especially in Finland, where broad assessments have been made regularly since the 1980s. They deliver information on the threat status of species and ecosystems, propose actions to guide conservation policy, and have the potential to spur transformative change.
Anni Arponen +4 more
wiley +1 more source
Dianci bileiqi, 2002 介绍了固相法和共沉淀包膜法制备氧化锌非线性电阻粉体的工艺 ,并比较了两种粉体制备方法对氧化锌非线性电阻电性能的影响。与固相法相比 ,共沉淀包膜法极大的改善了氧化锌非线性电阻微观结构均匀性 ,因此提高了氧化锌非线性电阻的电性能 ...
王兰义 +4 more
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Moving in Cycles: Explaining the Failure of Militarization to Address Illegal Mining in Ghana
Politics &Policy, Volume 54, Issue 4, August 2026.ABSTRACT Mining contributes to Ghana's economic growth but also imposes significant social costs—land dispossession and unemployment—which have fueled the rise of illegal mining (galamsey). Galamsey, which intensified during the commodity boom of the 2010s, provides livelihoods while simultaneously worsening environmental degradation and social ...
Sulemana Alhassan Saaka, Phil Faanu
wiley +1 more source
Guangtongxin yanjiu, 2020 针对偏振复用—正交相移键控（PDM-QPSK）无中继光纤传输系统中的非线性损伤问题,文章重点研究了一种基于K最邻近（KNN）聚类算法的非线性补偿技术。通过计算测试数据到所有训练数据点的距离对测试数据进行分类实现了对光纤非线性补偿。研究结果表明,在112 Gbit/s PDM-QPSK 350 km色散管理无中继光纤传输系统中,基于KNN算法的非线性补偿技术能够有效地补偿传输光纤非线性引起的损伤。特别地,在系统误码率为10-3时,经KNN算法非线性补偿后输入端信号的光功率可提升约1 dBm。
田霖 +7 more
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Policy Studies Journal, Volume 54, Issue 3, August 2026.ABSTRACT This paper examines how experts exert influence within China's one‐party system, where policymaking is ideologically disciplined and knowledge‐intensive. It combines the Functional Theory of Agency, which identifies patterns of action including accumulation of knowledge, brokerage, entrepreneurship, and leadership, with a typology of four ...
Giliberto Capano, Yuchen Guo
wiley +1 more source