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Journal of Healthcare Engineering, Volume 2018, Issue 1, 2018., 2018 A terminology (or coding system) is a formal set of controlled vocabulary in a specific domain. With a well‐defined terminology, each concept in the target domain is assigned with a unique code, which can be identified and processed across different medical systems in an unambiguous way.
Yinsheng Zhang +2 more
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Gaoya dianqi, 2023 雷电感应过电压是引起配电网故障的主要因素之一。为收集配电线路上的感应雷过电压数据，研究其波形特性，以期用于指导架空配电线路的雷电防护，文中采用了一个自供电、无线传输的雷电过电压在线监测装置，接触测量了配电线路中雷电感应过电压信号。通过对某10 kV配电线路上雷电感应过电压波形进行观测，并根据波形特征获取过电压相关波形参数。结果显示，感应雷过电压主要以高频分量形式叠加至工频相电压，所观察到的感应雷过电压波表现为波头时间短、波尾出现双极性高频振荡，最终衰减到零的特点 ...
徐文华 +7 more
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Gaoya dianqi, 2021 为提升GIS升压站雷电侵入波过电压防护水平,基于电磁暂态计算软件建立雷电侵入波过电压仿真计算模型,分析不同因素对雷电侵入波过电压影响的规律及特点,计算确定不同运行方式下的过电压水平,进而提出雷电侵入波过电压防护措施。结果显示:杆塔接地电阻对各设备过电压水平的影响不尽相同,杆塔冲击接地电阻并不是越低越好,在一定的范围之内存在对侵入波防护有利的最佳值;由于站外进线段各基杆塔塔型不同,落雷点到变电站的距离越大,站内设备上的过电压水平不一定越小;优化避雷器布置方式,在并联电抗器处设置一组避雷器后 ...
田金虎, 刘渝根, 赵俊光
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT High‐entropy oxides (HEOs) are promising for microwave absorption but suffer from a trade‐off between impedance matching and attenuation, often requiring high filling ratios (> 50 wt%). Herein, we propose a “lattice‐spin” dual‐regulation strategy by introducing giant‐radius Bi into a single‐phase HEO solid solution.
Junwei Zhang +11 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT The growing deployment of high‐frequency electronic systems has intensified the demand for high‐performance microwave absorption materials. In this work, we developed La‐V co‐substituted barium hexaferrites, Ba1‐xLaxFe11.9V0.1O19 (BLFVO), via a sol‐gel route.
Zhihui Yang +7 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT In recent years, materials capable of achieving efficient electromagnetic wave (EMW) absorption over a broad frequency range have attracted widespread attention. Such materials are not only significant in mitigating electromagnetic interference and pollution caused by the extensive use of electronic devices but also demonstrate outstanding ...
Maoxia Lu +7 more
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT Considering the multiple challenges faced by stealth coatings in complex service environments, the development of multifunctional integrated microwave absorbing materials (MAMs) that combine efficient electromagnetic (EM) attenuation with environmental tolerance has become an urgent need. In this work, coral‐like CoNi@Void@C microparticle (MP)
Jiale Wu +8 more
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT Although magnetic carbon materials possess significant potential in the field of electromagnetic wave absorption (EWA) due to the synergistic effect of multiple attenuation mechanisms, the currently reported magnetic carbon EWA materials face some challenges, such as high cost, low yield, and easy agglomeration of the magnetic component ...
Bo Jiang +9 more
wiley +1 more source
Dianci bileiqi, 2015 雷电流参数是输电线路雷电过电压分析和雷电防护分析的基础。总结了雷电流波形实测参数和雷电流模型,分别从波形和频谱两个方面对典型的雷电流模型进行了对比研究。利用PSCAD建立±800 k V特高压直流线路模型,采用不同的雷电流模型计算了线路的反击和绕击耐雷水平,结果表明:Heidler波和Concave波波头呈凹形,Concave波波头较Heidler波、双指数波和斜角波与实测雷电流波头最为接近。各雷电流模型的频谱都主要集中在0100 k Hz以内,能量主要集中在050 k Hz以内 ...
唐力 +4 more
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Dianci bileiqi, 2015 10 kV线路避雷器雷击放电电流是其试验方法、型号选择和运行寿命评估的关键问题。采用电磁暂态程序（EMTP）和电气几何模型法,分析了首次和后续雷击典型结构10 kV线路杆塔和导线的情况下,首次雷击和后续雷击的雷电流波头、波尾和幅值概率分布、杆塔接地电阻和杆塔高度等因素对避雷器放电电流的影响。结果表明:首次雷击引起的避雷器放电电流幅值、波尾、年预计雷击数比后续雷击大得多;取雷电流中值波头、中值波尾首次雷击杆塔情况下,避雷器放电电流波形能量大于标称放电电流8/20 s波形;雷电流幅值分布中值电流增大 ...
祝达康 +5 more
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