Results 51 to 60 of about 24,333 (149)
Dianci bileiqi, 2017 分析了大型回路中散射电压的传播对回路雷电感应过电压的影响。采用两种结构的传输线模型搭建回路:地面布置有两条传输线以及地面仅布置一条传输线。研究结果表明:由标量势引入的感应电场分量也能在回路中产生散射电压,并且散射电压的传播会在感应电压波形中引起很大的振荡,振荡波幅值和波长随着回路长度的增加而增加。当传输线回路布置在地面上方（架空线）时,电场在有耗地面中的发展和变化对回路感应电压没有影响,当传输线回路紧贴地表布置时,有耗地面中电场的发展变化将对回路感应电压产生很大影响。
杜晓华, 张定军
doaj
Policy &Internet, Volume 18, Issue 4, December 2026.ABSTRACT This paper examines the practices ordinary social media users employ to influence the content served to them by platform algorithms, and the relationship between these practices and levels of algorithmic literacy. Practices were documented across TikTok, Facebook, Instagram, Twitter (now X), YouTube and Reddit during 65 sessions, conducted as ...
Agata Stepnik, Joanne Gray
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表面活性剂胶束对Belousov-Zhabotinsky振荡反应的影响
四川大学学报. 自然科学版, 2009 采用我们自己开发设计的无纸记录仪器,从铈离子催化的经典B-Z振荡反应出发,探讨了三种不同类型的表面活性剂即阳离子表面活性剂CTAB,非离子表面活性剂Brij35和阴离子表面活性剂SDS对其振荡行为的影响。实验结果表明:当表面活性剂浓度大于其在该溶液中的临界胶束浓度时,都会对振荡反应造成一定的影响,不同的表面活性剂其影响程度的大小和趋势也有所不同。
罗冬丽 +5 more
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Gaoya dianqi, 2020 户内变电站中气体绝缘金属封闭开关设备（GIS）通常布置在2层楼面上,地震作用下,楼面电气设备受到生产综合楼结构对地震动的放大作用而产生较强烈的动力响应。文中结合某220 kV户内变电站结构,对楼面众多GIS电气设备进行了精细化有限元建模,对生产综合楼——楼面GIS电气设备整体模型和生产综合楼主结构模型分别进行动力特性分析和地震时程响应分析。结果发现:①主结构模型和主—附结构模型的前3阶频率和振型均相近;②2层楼面加速度峰值放大系数超过2.0,3层楼面加速度峰值放大系数超过3.0 ...
樊庆玲 +4 more
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First, He Was Adam, and Then, She Was Eve
Sexuality, Gender &Policy, Volume 9, Issue 4, November 2026.ABSTRACT Trans* is an umbrella term that is used to describe people who identify with a gender that is different from their assigned sex at birth. There has been a marked increase in young people presenting to child and adolescent mental health services due to a lack of specialist gender clinics in the United Kingdom.
Corey Hartley +2 more
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World Food Policy, Volume 12, Issue 2, November 2026.ABSTRACT Household food expenditure continues to be a key factor in ensuring the realization of the Human Right to Adequate Food. Particularly in Brazil, access to food can be limited by economic constraints in vulnerable families, especially among farming families, who have been more vulnerable to food insecurity in recent years in the country.
Lucas de Almeida Moura +3 more
wiley +1 more source
基于Ansys Workbench的不同截面型式自力型触指/触头配合结构优化设计
Gaoya dianqi, 2017 采用Cu-Cr合金材料,利用Solidworks建立自力型触指的矩形和W型截面触指/触头配合结构三维模型;通过DOE分析选取设计变量;运用Ansys Workbench的参数目标驱动优化对其结构参数进行了优化仿真。2种不同截面配合结构的最大应力和最大变形量的对比显示:随着触头直径、触指厚度以及摩擦行程的增大,各响应变量与之成正比例关系,且触头直径与摩擦行程对响应变量的影响比触指厚度的变化对响应变量的影响更大。经过多目标驱动优化后,矩形触指的最大变形量为6.6 mm,而W型触指最大变形量为2.6 mm ...
杨帆, 邓斌, 王国志, 刘桓龙
doaj
World Food Policy, Volume 12, Issue 2, November 2026.ABSTRACT Agricultural development initiatives in sub‐Saharan Africa have emphasized improved crop varieties as a pathway to food security, resilience, and rural poverty reduction. However, empirical evidence often focuses narrowly on plot‐level outcomes and overlooks whole‐farm effects and the substantial heterogeneity in farmers' management practices,
Kodjo Kondo +4 more
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Gongye shui chuli随着工业的快速发展，成分复杂、毒性强、难降解工业废水的高效处理已成为环境保护领域的重大挑战。膜分离技术因其具有高效、节能和无相变等优点被广泛应用，但传统膜材料面临的膜污染、选择性低和分离精度不足等问题限制了其进一步发展。环境响应膜（ERMs）作为一种新型智能膜材料，能够对外部环境刺激（如pH、温度、光、离子强度等）产生响应，并可逆地调节其物理化学性质（如孔径、亲疏水性、表面电荷），从而实现对特定污染物智能化、高选择性的分离与富集，为解决上述难题提供了新策略。综述了ERMs的分类及其响应机理 ...
张靖楠 +3 more
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Zhendong Ceshi yu Zhenduan针对应答器周围存在大量金属物影响其电磁传输性能的问题，在电磁场仿真软件中建立应答器天线模型，从金属面面积、金属面到应答器垂直距离及金属面厚度3个方面进行仿真实验，得到不同参数下应答器上行链路信号幅度曲线，计算应答器传输性能指标值并分析其传输性能所受的影响。研究表明：金属面面积越大，应答器传输模块（balise transmission module， 简称BTM）接收安全报文帧数等性能指标越小，且减小程度越明显，来自旁瓣区的干扰越大，当金属面积大于320 mm×320 mm时 ...
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