Results 31 to 40 of about 1,230,545 (167)
Gaoya dianqi, 2018 为提高输电线路的故障测距性能,笔者综合分析了工频法和行波法二者之间的测距特点,并提出了一种综合应用工频量法和单端行波法的组合故障测距法。首先,基于输电线路的沿线电压幅值分布规律,利用切线交叉的工频测距原理,初步确定故障区域,接着,在此基础上用A型行波法精确地测出故障位置。通过引入行波测距避免工频测距后续的迭代计算,克服迭代不收敛或收敛至伪根的问题,提高测距精度;用工频初步测距,缩小行波波头辨识范围,提高行波测距可靠性。经仿真验证:所提组合法比工频法测距精度更高,比行波法的波头识别更加准确可靠。
李振兴 +4 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT The development of lightweight, high‐attenuation, and broadband carbon‐based electromagnetic wave absorbers is hindered by the intrinsic trade‐off between impedance matching and dielectric dissipation. Herein, we report a facile and scalable synthesis of N‐doped lignin‐derived interconnected porous carbon (Nx‐LIPC) via hydrogen‐bond self ...
Bin‐Peng Zhang +7 more
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Typological Classification and the Chronology of Iron Age pottery in central-southern Britain [PDF]
, 2012 Pottery has been one of the most popular artefacts in the study of the Iron Age in central-southern Britain because of its advantages of commonality, durability and volume.
NISHITANI, AKIRA
core
, 1998 海面微波散射反演是星载微波器遥感海面风场技术的一个关键组成部分。考虑到目前海面微波散射反演工程模型的纯经验性和依赖散射计工作频率等局限，以及以双尺度理论为代表的物理模型中对短波谱该画存在的明显不足，本文致力于建造一个既有理论基础又具实际应用可行性的微波散射模型。根据在风水槽实验中获取的风生短波频谱实测数据以及现有不同波段的实际微波散射资料的分析，文中提出了一个适于散射反演的风生波短波谱形式，进而建立起一个可实际应用的海面微波散射模型。基于本文提出的微波散射模型 ...
徐丰
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Because magnetic permeability is an intrinsic property of materials, achieving the regulation of magnetic loss is one of the challenges for electromagnetic wave absorption materials. This paper focuses on the research idea of in situ growth of dispersed nanocrystalline FeSiB in an amorphous FeSiB matrix to regulate magnetic properties.
Lei Wang +4 more
wiley +1 more source
四川大学学报. 自然科学版, 2015 在线性近似下,Helmholtz方程能够描述小尺度大气声波波动.因此分析小规模大气声波波动特性,必须对Helmholtz方程进行求解.大多数求解Helmholtz方程的方法是在某些边界条件和初始条件下进行的,而边界条件和初始条件本身就是在假设、近似的基础上得到的,且会使得计算过程复杂和计算量变大.指数函数法具有多个自由参数是求解非线性问题精确解的一种十分有效、直接的工具,且在求解时不要考虑边界条件和初始条件,对函数进行指数和双曲正切变换的共同作用可近似为线性变换.基于上述思想 ...
纪娟娟, 郭业才, 张兰芳
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Structural Modulation of Magnetic Softness in Fe‐Based Amorphous Alloys via Pulse Current Training
Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Fe‐based amorphous alloys, despite their intrinsically low magnetocrystalline anisotropy, suffer from quasi‐dislocation dipoles and localized stress fields that impede domain‐wall motion and increase coercivity. Here, we introduce pulse current training (PCT) as an energy‐efficient technique to overcome these limitations in a Fe76Si9B10P5 ...
Shumin Ye +13 more
wiley +1 more source
Guangtongxin yanjiu, 2008 文章提出一种将光相移键控（PSK）调制用于基于谐波生成原理的毫米波光纤无线电（ROF）下行链路系统,在生成毫米波的同时,实现了二进制相移键控（BPSK）调制,并且通过加入并行光载波抑制双边带调制（DSB-SC）支路实现了导频的产生,供毫米波下变频之用。仿真结果验证了毫米波的产生和信号的调制解调过程,证明了该下行链路系统的可行性。
朱美伟 +3 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Integrating light emission and electromagnetic wave (EMW) absorption into a single material opens up possibilities for multienvironmental applications. Herein, we propose a novel “molecular engineering‐pyrolysis conversion” strategy to construct a bifunctional system with tunable photoluminescence and efficient EMW absorption performance.
Renjie Wang +7 more
wiley +1 more source
Gaoya dianqi, 2012 母线采用第二类接线方式,考虑母线分布电容,建立输电线路模型。对行波线模分量进行小波变换以及模极大值处理,利用模式识别,建立隶属度函数,对故障初始行波、故障点反射波、对端母线反射波进行标定,得到1组时刻组合（t1m,t2m,t3m）。经过单端行波测距计算,获得2个测距结果x和（L-x）,其中1个测距结果为伪根,给出去除该伪根的方法。理论分析和EMTP仿真验证,该文测距方法不受波速影响,并且具有很高的测距精度,较好的抗干扰性和抗过渡电阻能力。
胥杰 +5 more
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