Results 71 to 80 of about 622,343 (193)
Gaoya dianqi, 2010 断路器在随机关合空载变压器时会产生幅值、频率很高的励磁涌流,这种操作暂态可能导致微机继保装置误动作,降低用户电能质量和系统可靠性。根据空载变压器涌流产生的机理,采用选相关合技术消除变压器励磁涌流,研究了铁心剩磁和最佳关合相位关系;分析了断路器截流和暂态恢复电压对铁心剩磁影响,并给出了剩磁测量方法。在空载变压器选相关合原理基础上,采用ATP-EMTP软件建立空载变压器关合模型,对暂态过程进行了仿真。仿真结果表明,选相关合技术能有效消除空载变压器合闸时产生的励磁涌流,为空载变压器选相关合提供了理论基础。
李伟 +4 more
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Policy &Internet, Volume 18, Issue 3, September 2026.ABSTRACT Democratic innovations increasingly take place online, yet little is known about how online citizen participation affects perceived legitimacy compared to in‐person formats. This study presents findings from a preregistered vignette experiment conducted in Spain and Switzerland.
Valeria Vuk
wiley +1 more source
Whose Digital Future? Civil Society and Alternative Imaginaries in Transnational Digital Governance
Policy &Internet, Volume 18, Issue 3, September 2026.ABSTRACT This article investigates different visions of digital futures, examining how desired futures are discursively constructed within civil society in transnational digital governance. The analysis builds on discourse theory and a growing body of research on imaginaries in digital governance.
Outi Puukko
wiley +1 more source
Trust in the Machine? Practitioner Perspectives on the Role of AI in Online Content Moderation
Policy &Internet, Volume 18, Issue 3, September 2026.ABSTRACT The scale and volume of user‐generated content produced in the Web 2.0 era have led to content moderation becoming an essential aspect of most online platforms' business models. This form of digital labour is often performed by human content moderators (CMs) in the Global South, however, artificial intelligence (AI) technology has increasingly
Elena Martellozzo +4 more
wiley +1 more source
四川大学学报. 自然科学版, 2011 本文主要是研究金属铁经历冲击—卸载到熔化压力区,其内部发生熔化相变时,铁/蓝宝石界面的辐亮度和温度随时间演化特性,发现辐亮度随时间持续增强而界面却经历了一个慢降温过程,该特征与无相变或瞬时相变的热传导模型结论不一致,即无熔化相变或瞬时相变时,界面温度是一个稳定值.本文结合熔化相变动力学模型与热传导方程对实验现象给出一种理论解释.模型计算所给出的温度历史与观测结果一致,由此可以校对其它测量或者计算熔化温度的方法和模型计算的结果,并能够初步限定出该压力下铁的熔化成核速率和径向长大速率.
张世来 +5 more
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Poverty &Public Policy, Volume 18, Issue 3, September 2026.ABSTRACT This paper examines the impact of the COVID‐19 pandemic on income and wealth inequality in Switzerland, with a particular focus on poverty dynamics and the role of the social security system. Using newly linked administrative tax data for four large cantons covering over a third of the Swiss population, we track changes in household income and
Oliver Hümbelin +2 more
wiley +1 more source
, 2010 铝镍钴磁体自十九世纪三十年代问世以来便在二战中应用于电子设备，而今稀土永磁材料因其优异的剩磁和磁能积等性能在许多应用领域都取代了铝镍钴材料。然而，铝镍钴合金由于其极低的温度系数（0.02%/℃）和极高的工作温度等优点，仍被应用于精密仪器和传感器等产品。 本文系统研究了Alnico8合金的显微结构及相变温度，并测试了不同处理状态的合金的磁性能。利用金相观测法测定了柱状晶的尺寸；运用差热分析仪（DSC）测定了铁磁相变温度点的区间；利用透射电子显微镜（TEM）研究了不同条件下合金的微观组织；采用小角X射线散射（
孙可卿
core
Ni‐Induced Interface Refinement Enhances Strength‐Ductility Synergy in LPBF‐Processed Ti‐Mo‐Ni Alloy
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Microstructural refinement is a common strategy for strengthening additively manufactured titanium alloys because it promotes phase nucleation. Reducing the α/β interfacial formation energy is an effective way to increase the nucleation rate.
An Li +6 more
wiley +1 more source
一种平面相变存储器的制备方法，包括：在衬底上依次生长一层电热绝缘材料层，相变材料层和基底材料层；去除基底材料层的四边，形成基底；在相变材料层的上面和基底材料层的表面及侧面淀积侧墙材料层；去除基底材料层上表面的和相变材料层表面的侧墙材料层，在基底材料层的侧面将形成高和宽均为纳米尺寸的侧墙；去除基底材料层，只保留纳米尺寸的侧墙；去掉除了侧墙底部以外的所有相变材料，从而形成由侧墙和相变材料层构成的叠层侧墙；在该侧墙的一条边上搭上一条制作电极的金属层；去除侧墙以及侧墙表面上的金属层 ...
马慧莉 +5 more
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Zhongguo shiyan zhenduanxue, 2017 恶性肿瘤是一种体细胞遗传病,为相关基因结构与功能发生改变的结果,本文就大肠癌与之相关的基因突变及遗传易感性进行综述。1肿瘤的发生与基因突变的关系恶性肿瘤的发生及发展与相关的基因结构及其相关的功能发生改变有关。这些基因参与调控细胞的的正常生长周期、细胞的死亡及DNA的损伤修复。基因的种系突变（germ line mutation）在遗传性恶性肿瘤中起主要作用[1]。突变是生物进化的必要条件之一,没有突变就没有进化 ...
侯睿智, 舒振波, 侯睿达, 刘艳
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