Results 11 to 20 of about 7,356 (116)

Gravity‐Driven Inclination Sensor Based on Liquid Metal Interface Migration in Anisotropic Microchannels for Information Transmission and Continuous Surface Topography Scanning

open access: yesRare Metals, Volume 45, Issue 2, February 2026.
ABSTRACT With the continuous advancement of materials science and technology, the rare metal gallium has increasingly emerged as a promising alternative to the toxic metal mercury. Although existing research has predominantly focused on the high electrical conductivity and excellent deformability of liquid metal (LM), its intrinsic fluidic property ...
Feifan Guo   +6 more
wiley   +1 more source

Beyond Motivation: Modeling the Predictive Role of L2 Pride in Informal Digital Learning of English

open access: yesInternational Journal of Applied Linguistics, Volume 35, Issue 4, Page 1938-1952, November 2025.
ABSTRACT This study investigates the role of second language (L2) pride—an understudied affective factor—in shaping learners’ language learning motivation and involvement with informal digital learning of English (IDLE). Drawing on questionnaire data from 1388 Chinese university EFL students, the study employs structural equation modeling to examine ...
Minlin Minny Zou   +3 more
wiley   +1 more source

Research and simulation of resonant earthed system Based on IPC [PDF]

open access: yes, 2008
我国中压配电网,绝大多数采用中性点不接地方式。这种接地方式最大的优点是:当发生单相接地时,三相线电压的对称性没有被破坏,所以用户用电不受影响,可维持一定长的时间。但是,当配电网达到一定规模,对地电容电流达到一定数值后,必须采取加装消弧线圈的措施来保证配电网的安全。 配电网中性点采用消弧线圈接地的方式,对于改善电网供电质量、提高供电可靠性和保证整个系统安全运行都有十分重要的意义。本文在此背景下,对谐振接地系统展开研究与仿真。首先介绍了中性点接地方式的发展过程,通过对谐振接地原理和单相接地故障的分析 ...
柯远青
core  

Implications of Tobacco Use on Pathogen‐Driven Diseases: A Public Health and Policy Perspective

open access: yesWorld Medical &Health Policy, Volume 17, Issue 3, Page 468-474, September 2025.
ABSTRACT The tobacco epidemic remains one of the most significant global public health challenges, responsible for over 8 million deaths annually, with a substantial portion occurring among non‐smokers exposed to second‐hand smoke. While cigarette smoking remains the most prevalent form of tobacco use worldwide, the rise of electronic nicotine delivery
Nadine Kabbani, James L. Olds
wiley   +1 more source

深井型直流接地极散流机理研究

open access: yesDianci bileiqi, 2020
准确计算直流接地装置的散流性能及接地特性是优化设计直流接地极的基础。提出了基于恒定电场理论的直流接地装置性能有限元数值计算模型,针对求解区域和接地导体截面尺寸的差异导致的剖分困难、计算量大的问题,引入"薄壳"理论,在保证计算精度的前提下大大减小了计算量;通过与文献数据对比,验证了该方法的有效性。建立典型结构的深井型接地极模型,计算深井接地极散流过程产生的地中电流密度、电场强度、接地电阻和最大跨步电压等参数;分析电流注入点个数、接地极导体长度、接地极埋深、导体并联根数以及土壤电阻率等因素对接地性能的影响 ...
李景丽, 冯鹏, 栗超超
doaj  

Design of Low Drop-Out Regulator with Low Voltage [PDF]

open access: yes, 2009
随着工艺的发展及许多SOC产品及便携式电子产品的工作电压不断下降,省电观念越来越引人注目,对提供电源的芯片要求越来越高。针对供电电源日趋低压化,以及节能环保意识成为各个国家及众多消费者的共识,低电源电压下能工作且具有低功耗成为线性稳压器的发展趋势。本文提出了一种输出电压1.5V,输入电压可以低至1.7V的情况下稳定工作并能提供300mA电流的低压差线性稳压器电路,整个线性稳压器电路的静态电流低于40uA。与传统的低压差线性稳压器相比,本文设计的低压差线性稳压器电路系统提出了利用有源前馈米勒补偿(AFFC)
肖华
core  

Parliament, petitions and pandemic: Conspiracism in Australia's federal e‐petitions system, 2020−2021

open access: yesPolicy &Internet, Volume 16, Issue 3, Page 485-508, September 2024.
Abstract During the COVID‐19 pandemic, some groups and individuals rearticulated state power through conspiracy theories. Despite their fringe status, conspiracy theory beliefs can directly animate citizen's engagements with institutions. Drawing on Barkun's ‘conventional’ and ‘stigmatised’ knowledge types, we analyse the appearance of conspiracism in ...
Ben Lyall, Patrick Marple
wiley   +1 more source

计及回流电流和分流电流影响的接地参数分析计算

open access: yesDianci bileiqi, 2016
在以往的接地参数计算中,直接将站内和站外不对称短路时的最大入地短路电流从接地网边角注入来计算各个接地参数,而忽略了短路过程中形成的回流电流和分流电流,这造成某些接地参数计算误差较大。本文以某电站的短路电流分布为例,计算分析了回流电流和分流电流对接地参数计算的影响,并研究了在计及回流电流和分流电流的情况下各个敏感因素对接地参数的影响。研究表明:计及回流电流和分流电流后,GPR会增大一定的幅度,但电位梯度和网内电位差相比只考虑入地短路电流时会增大很多,地表电位不均衡程度大大增大,接触电势和跨步电势也相应增大。
郭婷婷, 文习山, 杨琪
doaj  

配电网中性点改造为小电阻接地方式的安全性分析研究 附视频

open access: yesDianci bileiqi, 2022
我国大中城市配电网出线数量增加及线路电缆化率提高,消弧线圈难以满足电容电流补偿要求,在用电量集中的工商业区开展配网小电阻接地改造及系统安全性研究对其安全稳定运行具有重要意义。首先基于单相接地故障电路模型对中性点小电阻接地系统单相接地故障短路电流进行了理论计算;其次在Matlab-Simulink中搭建消弧线圈接地系统(NES)向小电阻接地系统(NRS)进行负荷倒切的暂态仿真模型,模拟10 kV/380 V配电变压器高压侧外壳保护与低压侧工作保护共用接地背景下的高压侧碰壳故障,其中为准确计算流过人体的电流,
doaj  

动车组接地回流分配机理试验研究

open access: yesGaoya dianqi, 2016
随着高速列车的不断提速,牵引功率不断提升,导致接地回流逐渐增大,轴承电势升高、电蚀加重,严重威胁列车运行安全。文中基于现场试验,通过现场测试CRH380系列动车组接地回流,分析了工作接地与保护接地分配规律,研究了动车组接地方式对牵引回流的影响。结果表明:保护接地电流与工作接地电流波形变化趋势基本一致,工作接地电流最大值为398.45 A,总工作接地电流占车体回流的72.29%;头尾车保护接地电流最大,约占总保护接地电流的66.68%。以上结论为设计车体接地系统提供了实践基础。
陈盼   +5 more
doaj  

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