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文章速递“电磁场与电磁波”课程可视化方法研究 认领
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作者 卫延 《电气电子教学学报》 2021年第1期51-54,98,共5页
本文将“电磁场与电磁波”课程中的可视化问题进行了分类,指出了每类问题可视化的方法、应用软件与注意事项。电磁场是矢量场,矢量线(电力线和磁力线)图清晰、美观,不仅能反映电磁场的全局概况和场与源的关系,还能全面描述电磁场的性质... 本文将“电磁场与电磁波”课程中的可视化问题进行了分类,指出了每类问题可视化的方法、应用软件与注意事项。电磁场是矢量场,矢量线(电力线和磁力线)图清晰、美观,不仅能反映电磁场的全局概况和场与源的关系,还能全面描述电磁场的性质,但是难以绘制,本文根据实例详述了用Matlab绘制矢量线图的方法和技巧。 展开更多
关键词 电磁场 电磁波 可视化 Matlab
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玻璃镜片度数与透射特性关系仿真研究 认领
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作者 莫洪波 严映华 +1 位作者 戴宗贤 尹爱军 《陶瓷学报》 CAS 北大核心 2021年第1期130-135,共6页
防辐射眼镜能够减少环境中电磁辐射对人眼的损伤,对于眼镜佩戴者的生活质量和健康安全来说具有重要的意义。防辐射眼镜分为镀膜防辐射和通过镜片本身防辐射两种。本文针对镜片防辐射的场景,基于CST-Microwave Studio建立了电磁波镜片透... 防辐射眼镜能够减少环境中电磁辐射对人眼的损伤,对于眼镜佩戴者的生活质量和健康安全来说具有重要的意义。防辐射眼镜分为镀膜防辐射和通过镜片本身防辐射两种。本文针对镜片防辐射的场景,基于CST-Microwave Studio建立了电磁波镜片透射性仿真模型用以仿真不同度数下电磁波的透射性,研究了150°-600°镜片度数范围内100 MHz-3000 MHz频段电磁波的透射特性。研究表明电磁波射入镜片的透射率随电磁波频率和镜片度数的增加而增加,并且具有波动性。在较低频段内,镜片的电磁波透射性由于波动性的影响导致透射率随度数增加的趋势不明显;在较高频段,透射率随度数增大而增加的趋势明显,受波动性的影响镜片的透射性呈阶梯增大的趋势。 展开更多
关键词 玻璃镜片 电磁波 透射特性
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基于透射型几何相位编码超表面的太赫兹波束自由操控 认领
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作者 唐小燕 柯友煌 +3 位作者 井绪峰 别寻 李晨霞 洪治 《光子学报》 EI CAS 北大核心 2021年第1期142-155,共14页
为了实现太赫兹波束的自由操控,基于Pancharatnam-Berry几何相位理论,提出一种多层C型单元结构,实现在目标频率下0到2π的太赫兹波透射传输相位调控。基于广义斯涅耳定律,构建2-bit和3-bit编码超表面,在圆偏振入射条件下,实现透射型太... 为了实现太赫兹波束的自由操控,基于Pancharatnam-Berry几何相位理论,提出一种多层C型单元结构,实现在目标频率下0到2π的太赫兹波透射传输相位调控。基于广义斯涅耳定律,构建2-bit和3-bit编码超表面,在圆偏振入射条件下,实现透射型太赫兹波束的散射角度调控。采用数字信号处理理论中的傅里叶卷积运算,对不同周期序列的编码超表面进行四位制编码卷积运算,获得新的编码序列,实现对透射太赫兹波散射角度的自由调控。利用多层C型编码超表面单元结构对其进行旋转编码,实现1阶和2阶涡旋相位板,产生不同阶数太赫兹波涡旋光束。 展开更多
关键词 电磁波 超表面 太赫兹波 傅里叶卷积 几何相位 散射
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文章速递Broadband asymmetric transmission for linearly and circularly polarization based on sand-clock structured metamaterial 认领
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作者 傅涛 刘兴兴 +3 位作者 文国华 孙堂友 肖功利 李海鸥 《中国物理B:英文版》 SCIE EI CAS CSCD 2021年第1期229-233,共5页
We proposed a sandwich structure to realize broadband asymmetric transmission(AT) for both linearly and circularly polarized waves in the near infrared spectral region. The structure composes of a silica substrate and... We proposed a sandwich structure to realize broadband asymmetric transmission(AT) for both linearly and circularly polarized waves in the near infrared spectral region. The structure composes of a silica substrate and two sand-clock-like gold layers on the opposite sides of the substrate. Due to the surface plasmons of gold, the structure shows that the AT parameters of linearly and circularly polarized waves can reach 0.436 and 0.403, respectively. Meanwhile, a broadband property is presented for the AT parameter is over 0.3 between 320 THz and 340 THz. The structure realizes a diode-like AT for linearly wave in forward and circularly wave in backward, respectively. The magnetic dipoles excited by current in the two gold layers contribute to the broadband AT. The current density in top and bottom metallic layers illustrates the mechanism of the polarization conversion for broadband AT in detail. 展开更多
关键词 asymmetric transmission metasurface polarization conversion trerahertz broadband electromagnetic wave near-infrared
文章速递Propagation dynamics of relativistic electromagnetic solitary wave as well as modulational instability in plasmas 认领
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作者 唐荣安 刘调芳 +4 位作者 洪学仁 高吉明 程瑞锦 郑有莲 薛具奎 《中国物理B:英文版》 SCIE EI CAS CSCD 2021年第1期332-344,共13页
By one-dimensional particle-in-cell(PIC) simulations, the propagation and stability of relativistic electromagnetic(EM) solitary waves as well as modulational instability of plane EM waves are studied in uniform cold ... By one-dimensional particle-in-cell(PIC) simulations, the propagation and stability of relativistic electromagnetic(EM) solitary waves as well as modulational instability of plane EM waves are studied in uniform cold electron-ion plasmas.The investigation not only confirms the solitary wave motion characteristics and modulational instability theory, but more importantly, gives the following findings. For a simulation with the plasma density 10^(23) m^(-3) and the dimensionless vector potential amplitude 0.18, it is found that the EM solitary wave can stably propagate when the carrier wave frequency is smaller than 3.83 times of the plasma frequency. While for the carrier wave frequency larger than that, it can excite a very weak Langmuir oscillation, which is an order of magnitude smaller than the transverse electron momentum and may in turn modulate the EM solitary wave and cause the modulational instability, so that the solitary wave begins to deform after a long enough distance propagation. The stable propagation distance before an obvious observation of instability increases(decreases) with the increase of the carrier wave frequency(vector potential amplitude). The study on the plane EM wave shows that a modulational instability may occur and its wavenumber is approximately equal to the modulational wavenumber by Langmuir oscillation and is independent of the carrier wave frequency and the vector potential amplitude.This reveals the role of the Langmuir oscillation excitation in the inducement of modulational instability and also proves the modulational instability of EM solitary wave. 展开更多
关键词 electromagnetic solitary wave particle-in-cell(PIC)simulation modulational instability Langmuir oscillation
One-step synthesis and electromagnetic absorption properties of high entropy rare earth hexaborides(HE REB6)and high entropy rare earth hexaborides/borates(HE REB6/HE REB03)composite powders 认领
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作者 Weiming ZHANG Biao ZHAO +3 位作者 Huimin XIANG Fu-Zhi DAI Shijiang WU Yanchun ZHOU 《先进陶瓷:英文版》 SCIE 2021年第1期62-77,共16页
Considering the emergence of severe electromagnetic interference problems,it is vital to develop electromagnetic(EM)wave absorbing materials with high dielectric,magnetic loss and optimized impedance matching.However,... Considering the emergence of severe electromagnetic interference problems,it is vital to develop electromagnetic(EM)wave absorbing materials with high dielectric,magnetic loss and optimized impedance matching.However,realizing the synergistic dielectric and magnetic losses in a single phase material is still a challenge.Herein,high entropy(HE)rare earth hexaborides(REB6)powders with coupling of dielectric and magnetic losses were designed and successfully synthesized through a facial one-step boron carbide reduction method,and the effects of high entropy borates intermedia phases on the EM wave absorption properties were investigated.Five HE REB6 ceramics including(Ce0.2Y0.2Sm0.2Er0.2Yb0.2)B6,(Ce0.2Hu0.2Sm0.2Er0.2Yb0.2)B6,(Ce0.2Y0.2Eu0.2Er0.2Yb0.2)B6,(Ce0.2Ya2Sm0.2Eu0.2Yb0.2)B6,and(Nd0.2Y0.2Sm0.2Eu0.2Yb0.2)B6 possess CsCl-type cubic crystal structure,and their theoretical densities range from 4.84 to 5.25 g/cm^(3).(Ce02Y0.2Sm0.2Er0.2Yb02)B6 powders with the average particle size of 1.86 jim were found to possess the best EM wave absorption properties among these hexaborides.The RLmin value of(Ce0.2Y0.2Sm0.2Er0.2Yb0.2)B6 reaches-33.4 dB at 11.5 GHz at thickness of 2 mm;meanwhile,the optimized effective absorption bandwidth(EAB)is 3.9 GHz from 13.6 to 17.5 GHz with a thickness of 1.5 mm.The introduction of HE REB03(RE=Ce,Y,Sm,Eu,Er,Yb)as intermediate phase will give rise to the mismatching impedance,which will further lead to the reduction of reflection loss.Intriguingly,the HEREB6/HEREB03 still possess wide effective absorption bandwidth of 4.1 GHz with the relative low thickness of 1.7 mm.Considering the better stability,low density,and good EM wave absorption properties,HE REB6 ceramics are promising as a new type of EM wave absorbing materials. 展开更多
关键词 high entropy rare earth hexaborides(HE REB6) one-step synthesis electromagnetic wave absorbing properties synergistic dielectric and magnetic losses wide effective absorption bandwidth
电磁发射装置绝缘支撑的性能要求及材料应用综述 认领
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作者 巩博瑞 陈彦辉 +3 位作者 骆帅 李明涛 蒋丹宇 周国红 《火炮发射与控制学报》 北大核心 2021年第1期103-108,共6页
电磁发射是一种通过电路产生的洛伦兹力推动发射体进行加速的新型发射技术,与传统火药发射相较具有极大优势。绝缘支撑作为发射装置中的重要部件,其性能直接影响了装置整体的可靠性及寿命。以典型发射装置结构为例,简要介绍了绝缘支撑... 电磁发射是一种通过电路产生的洛伦兹力推动发射体进行加速的新型发射技术,与传统火药发射相较具有极大优势。绝缘支撑作为发射装置中的重要部件,其性能直接影响了装置整体的可靠性及寿命。以典型发射装置结构为例,简要介绍了绝缘支撑的安装形式及作用;在此基础上,参考国内外电磁发射研究,结合电磁发射原理,分析了绝缘支撑的性能需求;介绍了绝缘支撑材料的应用现状,分析了各种材料的优缺点及可能采用的改进方式,为后续绝缘支撑的进一步研究提供参考。 展开更多
关键词 电磁发射 绝缘支撑 应力波 绝缘复合材料 陶瓷材料
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机翼后缘电磁散射特性分析 认领
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作者 张维仁 艾俊强 王健 《电讯技术》 北大核心 2021年第2期242-247,共6页
采用多层快速多极子方法分析了梯形机翼后缘行波电磁散射和极化特性。针对机翼后缘半径和机翼展长等关键设计参数,建立了变参数模型并进行了多方案仿真分析,讨论了后缘半径和展长参数对机翼后缘行波在前向角域产生波峰的变化规律和散射... 采用多层快速多极子方法分析了梯形机翼后缘行波电磁散射和极化特性。针对机翼后缘半径和机翼展长等关键设计参数,建立了变参数模型并进行了多方案仿真分析,讨论了后缘半径和展长参数对机翼后缘行波在前向角域产生波峰的变化规律和散射量级。最后针对机翼后缘应用吸波材料的方案进行了计算分析,结果证明在机翼后缘应用吸波材料可以有效减缩后缘产生的行波散射。 展开更多
关键词 机翼后缘 电磁散射 行波 多层快速多极子方法
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股骨头坏死保髋治疗的新策略 认领
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作者 曾祥洪 梁博伟 《中国组织工程研究》 CAS 北大核心 2021年第3期431-437,共7页
背景:髋关节置换已成股骨头坏死治疗的一种终末手段,但早中期的股骨头坏死或者年轻患者往往优先考虑保髋治疗,包括保守治疗与手术治疗.目的:对目前股骨头坏死的各种保髋治疗进展进行总结.方法:应用计算机检索从2010年至2020年3月Pub Me... 背景:髋关节置换已成股骨头坏死治疗的一种终末手段,但早中期的股骨头坏死或者年轻患者往往优先考虑保髋治疗,包括保守治疗与手术治疗.目的:对目前股骨头坏死的各种保髋治疗进展进行总结.方法:应用计算机检索从2010年至2020年3月Pub Med、维普、CNKI及Web of Science数据库中有关股骨头坏死保髋治疗的文献,检索词为"osteonecrosis of femoral head,hyperbaric oxygen,pulsed electromagnetic fields,extracorporeal shock wave,hip arthroscopy,core decompression,stem cell transplantation,non-vascularized free bone grafting,vascularized free bone grafting,porous tantalum rod implantation,intertrochanteric osteotomy,medication".共检索到197篇文献,查阅全文,按照纳入标准,最后纳入59篇文献进行结果分析.结果与结论:(1)药物治疗因为其潜在的副反应以及研究开展不足,需谨慎使用;(2)物理治疗对于早期的病变疗效显著,而且具有无创、操作方便等优点;(3)保髋手术目前种类各异:髓芯减压是治疗股骨头坏死的基础疗法,单独使用已甚少,目前常通过与其他保髋疗法联合使用;截骨术在患者的适应证选择及手术技巧上有较高的要求,临床上应慎重选择;多孔钽棒置入存在手术时间长、失血量较大及后期髋关节置换难度增加等问题;干细胞及关节镜疗法显示出较好的效果,应加快研究进程;血管化植骨对中晚期的患者有着不错的疗效. 展开更多
关键词 关节 股骨头坏死 高压氧 脉冲 电磁场 冲击波 髓芯减压 骨移植 综述
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非线性科学,球形闪电和一般的三维非线性波的电磁孤子模型 认领
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作者 张一方 《安阳工学院学报》 2021年第2期90-93,108,共5页
非线性科学是当代科学发展的主要前沿之一。由此得到的地震震级-周期公式预报的地震,不断被证实。非线性引力波的预言也被证实。球形闪电是大自然中一个未解之谜。由非线性电磁场、非线性光学、一般的非线性电磁相互作用及其他非线性方... 非线性科学是当代科学发展的主要前沿之一。由此得到的地震震级-周期公式预报的地震,不断被证实。非线性引力波的预言也被证实。球形闪电是大自然中一个未解之谜。由非线性电磁场、非线性光学、一般的非线性电磁相互作用及其他非线性方程可以定量导出三维非线性波的电磁孤子模型,进而由此推测球形闪电应该是电磁孤子的特例。 展开更多
关键词 非线性 球形闪电 电磁场 孤子
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Deductions from the Quaternion Form of Maxwell’s Electromagnetic Equations 认领
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作者 Jeremy Dunning-Davies Richard Lawrence Norman 《现代物理(英文)》 2020年第9期1361-1371,共11页
<p align="justify"> <span style="font-family:Verdana;">It is often claimed that Maxwell’s electromagnetic equations were originally written in terms of quaternions. Once returned to th... <p align="justify"> <span style="font-family:Verdana;">It is often claimed that Maxwell’s electromagnetic equations were originally written in terms of quaternions. Once returned to that form and treated with left and right hand operators as in the mathematics of P. M. Jack, a new seventh scalar electromagnetic field component emerges with possible relations to clean energy extraction and gravitation. It is the purpose here to examine this approach afresh and see how it might link up with other fairly recent, but little known, work in the field. Again, as with the usual form of Maxwell’s equations, a new scalar wave equation is derived but, on this occasion, due to the presence of the scalar component of the quaternion, that equation exhibits a wave speed greater than the speed of light. Historical and present uses within military and humanitarian contexts are considered briefly.</span> </p> 展开更多
关键词 Electromagnetic Field QUATERNION GRAVITY MAXWELL Energy Scalar Wave
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Equivalence of String Classical and Quantum Energy beside Equivalence of Wave Packet and Relativistic Velocity in Eucleadian and Curved Space 认领
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作者 Mashair Ahmed Mohammed Yousif Abeer Mohammed Khairy Ahmed +5 位作者 Zainab Mustapha Kurawa Omer A. M. Elnor Mubarak Dirar Abd-Alla Yagoub Ibrahim Mohammed Elfaki El-Tahir Mohammed Idriss Ahmed Zoalnoon Ahmed Abeid Allah Saad 《自然科学期刊(英文)》 2020年第7期520-525,共6页
<span style="font-family:Verdana;">Plank quantum and classical string energy relations seem to be uncorrelated. This work correlated them. The relativistic energy-momentum relation has been used togeth... <span style="font-family:Verdana;">Plank quantum and classical string energy relations seem to be uncorrelated. This work correlated them. The relativistic energy-momentum relation has been used together with plank and de Brogglie hypothesis to prove that the wave group velocity is equal to the particle velocity in both ordinary and curved space. The plank energy relation is shown also to be related to the classical energy relation of an oscillating string. Starting from plank energy relation for n photons and performing integration, the expression of classical string energy was obtained. This means that one can treat electromagnetic waves as a collection of continuous photons having frequencies ranging from zero to w. Conversely, starting from classical string energy relation by differentiating it with respect to angular frequency, the plank quantum energy for n photons has been found. This means that the quanta results from separation of electromagnetic waves to single isolated waves. Each wave consists of n photons or quanta.</span> 展开更多
关键词 Plank Energy Classical Energy String Quanta PHOTONS Electromagnetic Waves Curved Space Group Velocity Wave Packet
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Aharonov-Bohm effect for bound states on spin-0 massive charged particles in a Gödel-type space-time with Coulomb potential 认领
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作者 Faizuddin Ahmed 《理论物理通讯:英文版》 SCIE CAS CSCD 2020年第7期36-41,共6页
In this paper,we investigate the relativistic quantum dynamics of spin-0 massive charged particles in a G?del-type space-time with electromagnetic interactions.We derive the radial wave equation of the Klein-Gordon eq... In this paper,we investigate the relativistic quantum dynamics of spin-0 massive charged particles in a G?del-type space-time with electromagnetic interactions.We derive the radial wave equation of the Klein-Gordon equation with an internal magnetic flux field and Coulombtype potential in the Som-Raychaudhuri space-time with cosmic string.We solve this equation and analyze the analog effect in relation to the Aharonov-Bohm effect for bound states. 展开更多
关键词 Göodel-type metrics relativistic wave equations bound states electromagnetic potential energy spectrum wave-functions
How Do Electric and Magnetic Fields Move? 认领
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作者 Vladimir Alexander Leus 《现代物理(英文)》 2020年第2期281-284,共4页
In nature, there are two fundamentally different types of motion of the electric and magnetic fields: dynamic and kinematic. A typical manifestation of the first type of motion takes place in a plane harmonic EM-wave.... In nature, there are two fundamentally different types of motion of the electric and magnetic fields: dynamic and kinematic. A typical manifestation of the first type of motion takes place in a plane harmonic EM-wave. For already more than a century the question about the ratio of the phases of the electric and magnetic fields, oscillating in such a wave, remains open. From time to time in this regard, fierce disputes arise. The point is that far from any phase difference turns out to be compatible with the full system of Maxwellian equations. Maxwell’s classical theory as applied to such a wave leads to the conclusion that the electric and magnetic vectors in it oscillate harmoniously with zero phase shift. In the framework of this theory, a rigorous mathematical proof is given. 展开更多
关键词 Electromagnetic Wave Transverse OSCILLATIONS in Phase Longitudinal IMMOBILITY of Field VECTORS Electro-Kinematics Magneto-Kinematics
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等离子体电磁波传播的仿真研究 认领
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作者 周勇 朱廷玉 +1 位作者 梁鑫 潘昱融 《现代雷达》 CSCD 北大核心 2020年第11期42-47,共6页
飞行器再入大气层时高速压缩周围气体,在高温作用下会在飞行器表面生成一层等离子体,导致通信信号难以传输,这是研究降低等离子体电磁波损耗的重要原因。文中针对电磁波在等离子体中的传播特性进行了理论分析,并在CST软件中建立了等离... 飞行器再入大气层时高速压缩周围气体,在高温作用下会在飞行器表面生成一层等离子体,导致通信信号难以传输,这是研究降低等离子体电磁波损耗的重要原因。文中针对电磁波在等离子体中的传播特性进行了理论分析,并在CST软件中建立了等离子体模型,仿真并分析了等离子体电波传播的损耗特性。为了改善电磁波通过等离子体层的能力,降低损耗,在等离子体区施加电场。仿真结果表明:施加电场后,对于频率f>7.25 GHz的电磁波,其在等离子体内的传播常数S21减小,传播能力提升,最大改善了6 dB。文中设计了等离子体试验箱,通过仿真研究得到了该试验箱等离子体分布,并据此研究了试验箱等离子体的电波传播能力,为实验提供理论参考。 展开更多
关键词 等离子体 电磁波 CST软件 S参数
微波技术在肉类解冻中的应用 认领
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作者 孙培清 《肉类工业》 2020年第4期49-50,共2页
实际生产中,肉类解冻对于保证产品质量、实现生产的自动化、提高出品率,以及环保等方面,越来越重要。相对于传统的解冻方式而言,微波技术在食品加工中的成功应用,是一次重大的技术进步。
关键词 电磁波 波谱图 微波技术
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On a Hypothetical Vector Field Associated with the Classic Electromagnetic Wave in a Space of Four Dimensions 认领
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作者 Leonardo Simal Moreira 《应用数学与应用物理(英文)》 2020年第12期2836-2845,共10页
In two previous papers <a href="#ref1">[1]</a> and <a href="#ref2">[2]</a>, a structure for vector products in <em>n</em> dimensions was presented, and at the sa... In two previous papers <a href="#ref1">[1]</a> and <a href="#ref2">[2]</a>, a structure for vector products in <em>n</em> dimensions was presented, and at the same time it was possible to propose the existence of a vector analogous to the curl of a vector field, for a space of four dimensions. In continuation of these works, the objective is to develop, through dimensional analogy, the idea of a hypothetical vector field, associated with the classical electromagnetic wave. This hypothetical field has a possible mathematical existence only when considering a space of four dimensions. The properties of the electromagnetic wave are preserved and equations with mathematical forms analogous to those of Maxwell’s equations are presented. 展开更多
关键词 Dimensional Analogy Electromagnetic Wave Four-Dimensional Space Vector Fields in Four Dimensions Analog of Maxwell’s Equations
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超短波理疗联合电针围刺法治疗脑卒中后肩手综合征的效果分析 认领
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作者 黄彩霞 夏静 +4 位作者 邵雅楠 陈虹 宋新建 曹娟娟 赵磊 《中华保健医学杂志》 2020年第5期490-492,共3页
目的探讨超短波理疗联合电针围刺法治疗脑卒中后肩手综合征的疗效及对上肢运动的影响。方法回顾性分析2017年5月~2019年8月南通市第二人民医院收治的脑卒中后肩手综合征110例患者的临床资料,按治疗方式的不同分为观察组(57例)和对照组(5... 目的探讨超短波理疗联合电针围刺法治疗脑卒中后肩手综合征的疗效及对上肢运动的影响。方法回顾性分析2017年5月~2019年8月南通市第二人民医院收治的脑卒中后肩手综合征110例患者的临床资料,按治疗方式的不同分为观察组(57例)和对照组(53例)。其中对照组患者接受超短波理疗,观察组接受超短波理疗联合电针围刺法。采集并比较两组治疗前后的上肢运动功能评分(Fugl-Meyer assessment,FMA)、疼痛视觉模拟量表(VAS)评分、水肿程度,评价治疗后两组的疗效。结果治疗后观察组和对照组的总有效率分别为96.49%和83.02%,差异具有统计学意义(P<0.05)。观察组和对照组治疗前FMA评分、VAS评分、水肿程度比较差异无统计学意义(P>0.05);治疗后两组FMA评分显著高于治疗前,VAS评分显著低于治疗前,水肿程度较治疗前均有显著减轻,差异有统计学意义(P<0.01)。治疗后观察组FMA评分为(48.82±3.65)分,高于对照组的(44.72±3.10)分;VAS评分为(2.13±0.61)分,低于对照组的(3.53±1.24)分;治疗后观察组的平均水肿得分低于对照组,组间比较差异均具有统计学意义(P<0.05)。结论超短波理疗联合电针围刺法应用于脑卒中后肩手综合征效果优于超短波理疗,可改善患者上肢运动功能,缓解疼痛,提高康复效率。 展开更多
关键词 超短波 电针围刺法 脑卒中后肩手综合征 上肢运动
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油田地面管道含水率测量装置的研究 认领
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作者 戴阳 《云南化工》 CAS 2020年第3期150-152,共3页
基于高频电磁波传播原理的含水率在线测量方法,改进测量装置的前端传感器及测量方式,完善含水率测量数据的处理方法,有效地模拟油田地面工况搭建了含水率测量实验平台,克服了现有的含水率测量装置在高含水率时测量区分度低、出现"... 基于高频电磁波传播原理的含水率在线测量方法,改进测量装置的前端传感器及测量方式,完善含水率测量数据的处理方法,有效地模拟油田地面工况搭建了含水率测量实验平台,克服了现有的含水率测量装置在高含水率时测量区分度低、出现"拐点"现象的缺点。 展开更多
关键词 管道 含水率 电磁波 传感器
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天线选型对隧道中电磁波传播的影响 认领
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作者 成凌飞 张薇静 +2 位作者 焦晓龙 刘肖鹏 陈诺 《传感器与微系统》 CSCD 2020年第9期20-23,共4页
针对天线选型对隧道中电磁波传播的影响,基于几何光学理论的射线追踪法,建立了矩形隧道的射线追踪信道模型,并通过仿真、实验验证分别探究了在900,1500,2100 MHz下天线选型对隧道中电磁波传播的影响。实验结果表明:在隧道内,发射天线为... 针对天线选型对隧道中电磁波传播的影响,基于几何光学理论的射线追踪法,建立了矩形隧道的射线追踪信道模型,并通过仿真、实验验证分别探究了在900,1500,2100 MHz下天线选型对隧道中电磁波传播的影响。实验结果表明:在隧道内,发射天线为定向天线时,其性能表现比全向天线要好,更适用于隧道环境;而在本文所考察的频段内,随着频率的增高,定向天线与全向天线的表现差异减小。所提研究对实际矩形隧道无线通信系统中,收发天线的选型和发射频率的选取具有参考意义,同时也对其他限定空间(如矿井巷道、地下人行通道、地铁等)的天线选取具有指导意义。 展开更多
关键词 天线 隧道 射线追踪 电磁波
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