Results 21 to 30 of about 5,764 (119)
Gaoya dianqi, 2020 真空灭弧室是机械式高压直流断路器的核心部件,为了有利于熄灭电弧,开断直流电流时,通常利用人工过零技术,在直流电流上叠加高频震荡电流,使得开断故障电流过零。由于直流断路器开断电流为高频电流,灭弧室间隙磁场分布对真空断路器的开断有着决定作用,通过建立三维真空灭弧室触头有限元模型,分析计算高频情况下的真空灭弧室的磁场分布情况。结果表明:高频情况下触头间隙磁场大小以及磁场滞后时间受到严重影响,触头间隙纵向磁场大小与平板触头产生效果类似,这对断路器开断效果很不利。
李如春 +5 more
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Corporate Quasi‐Sovereignty: Big Tech and the Politics of Sovereign Authority in the Digital Age
Policy Studies Journal, Volume 54, Issue 3, August 2026.ABSTRACT As private technology firms expand their control over critical infrastructures, questions of sovereignty and governance are increasingly displaced from states to corporate actors. Existing scholarship on sovereignty assumes that authority is either monopolized by states or shared through institutionalized public–private arrangements.
Chee Hae Chung, Bryce J. Dietrich
wiley +1 more source
Gaoya dianqi, 2014 针对交直流并行输电线路下方地面混合电场的特性,对交直流电场的相互影响作了分析,并对单根交流导线和单根直流导线形成的混合电场进行了试验研究。采用了基于Deutcsh假设的计算方法,对试验模型的地面混合电场进行了理论数值计算,试验结果与理论计算的结果相吻合,验证了该算法的有效性。最后,计算了实际的特高压交直流并行输电线路的地面混合电场,并与忽略交直流电场相互影响的计算结果进行对比,得出了交流线路的屏蔽效应将使地面直流离子流电场强度减小等结论。
鲁成栋, 肖登明, 秦松林
doaj
Justice in coexistence: Pastoralism and large carnivores on the Qinghai‐Tibet Plateau
People and Nature, Volume 8, Issue 7, Page 2186-2199, July 2026.Abstract The conflict between livestock husbandry and large carnivore conservation presents significant challenges in grassland ecosystems worldwide. Achieving sustainable coexistence among herders, livestock and large carnivores requires reconciling diverse perspectives and interests through equitable, inclusive and fair processes that address both ...
Yufang Gao, Yue Yu
wiley +1 more source
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT The development of high‐performance photodetectors critically relies on innovative interfacial band engineering, a strategy that enables the synergistic enhancement of photocurrent and drastic suppression of dark current. Herein, a self‐powered ultraviolet (UV) photodetector is demonstrated based on a NiO/La‐doped SrSnO3 (LSSO)/Nb‐doped SrTiO3
Wentian Zhang +7 more
wiley +1 more source
Gaoya dianqi, 2016 湍流模型参数的合理设置是气流场仿真中的要素之一。对于电流零区湍流模型的选择及湍流参数的设置,研究者持有不同的观点。文中针对零区气流场对标准k-epsilon湍流模型参数敏感度大小的问题,基于磁流体动力学原理,以252 k V压气式结构燃弧阶段的动态仿真为基础,计算了电流过零阶段湍流模型参数C1e对气流场的影响偏差百分比。通过特定监测点处气压与温度的对比,分析讨论了引起敏感度数值差异较大的原因。研究表明,湍流模型参数C1e的改变对喷口区域内气体压力的影响较小,对于气体温度的影响相对较大 ...
吴杰 +6 more
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Bio‐inspired artificial vision systems have made significant progress, but most focus on photo‐receptors, neglecting the hardware implementation of the efficient downstream neural circuits for complex computations like motion detection. To overcome this bottleneck, we demonstrate a neuromorphic vision system that mimics Drosophila's motion ...
Xianyu Hu +4 more
wiley +1 more source
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT The composition and structural characteristics of metacomposites are crucial for tuning their negative electromagnetic parameters; however, the lack of a clear structure–property relationship severely limits their application in dielectric and magnetic fields.
Chunyuan Deng +9 more
wiley +1 more source
Gaoya dianqi, 2019 换流变压器是高压直流输电工程的核心,换流变压器体积庞大、难以完整运输,一旦现场出现故障修复后则只能进行现场耐压试验以确保其投运后的安全运行。文中论述了国内外首次进行的±1100 kV换流变压器现场阀侧外施交流耐压试验及局部放电测量试验。±1100 kV昌吉换流站极Ⅰ高端换流变更换升高座后,为了检查其内部的绝缘强度和现场安装质量是否满足标准规程及产品技术条件要求,对极Ⅰ高端换流变压器进行阀侧外施交流耐压及局部放电测量试验。根据现场实际情况,通过合理布置试验设备位置、优化接地方式及接线方式 ...
卢理成 +6 more
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Wafer‐Scale Amorphous g‐C3N4 With Broadly Tunable Dielectric Properties for 2D Electronics
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Two‐dimensional (2D) semiconductors are regarded as promising candidates for next‐generation electronics due to their superior electrostatic control; however, their performance is severely constrained by the lack of suitable dielectric materials.
Binyin Gao +13 more
wiley +1 more source