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Propagating Characteristics of Confocal Elliptical Waveguide Filled with Multilayered Dielectrics

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Journal of Southwest Jiaotong University(English Edition) 2004年第2期12卷 130-135页

作者：熊天信杨儒贵 institute of electromagnetic fields and Microwave Technology Southwest Jiaoton University

Using the method of separation of variables in the elliptical coordinate system, a recursive formula for the electromagnetic fields in a confocal elliptical waveguide filled with multi-layered homogeneous isotropic media is derived; then the eigenequation for it is given. When an elliptical waveguide becomes a circular waveguide, the electromagnetic fields and the eigenequation of the circular waveguide can be obtained from the eigenequation of the elliptical waveguide using the asymptotic formulae of Mathieu and modified Mathieu functions for a large radial coordinate in the elliptical coordinate system, and the eigenequation of a circular waveguide filled with multilayered dielectrics can be treated as a special case of an elliptical waveguide. In addition, some numerical examples are presented to analyze the propagating characteristics influenced by the permittivity, permeability of dielectrics filled in the elliptical waveguide, etc. The results show that changing the permittivity or permeability of the dielectrics filled in the waveguide and the major semiaxis value of the i-th layer can change the propagating characteristics of an elliptical waveguide.

关键词： electromagnetic field Mathieu function Propagating constant Confocal elliptical waveguide Eigenequation

Accurate scattering centers modeling for complex conducting targets based on induced currents

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Science China(Information Sciences) 2021年第2期64卷 268-270页

作者： Guangliang XIAO Kunyi GUO Biyi WU Xinqing SHENG institute of Applied electromagnetic School of Information and ElectronicsBeijing Institute of Technology

Dear editor,According to the electromagnetic theory, each scattering center(SC) is equivalent to a mathematical discontinuity in Stratton-Chu integrals [1]. From the view of geometrical structure, the positions of SCs correspond to the discontinuities of surface and specular points. Therefore, the signatures of SCs in radar images can represent the actual geometric characteristics. Three-dimension SC model has been successfully applied for the radar target reconstruction and automatic target recognition(ATR) [2].

关键词： scattering center model induced currents complex target time-frequency representation (TFR) parameter estimation

Estimation of vector miss distance for complex objects based on scattering center model

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Science China(Information Sciences) 2021年第4期64卷 235-237页

作者： Jie WU Kunyi GUO Biyi WU Xinqing SHENG institute of Applied electromagnetic School of Information and ElectronicsBeijing Institute of Technology

Dear editor,This study presents a method to estimate vector miss distance (VMD) for complex objects based on scattering center (SC) models. In the method, the dependence of the SCs on the aspect angle of the light of sight (LOS) is applied in VMD estimation. This method requires only the radar echoes in a short time frame when the flying object approaches to the closet point of approach (CPA).

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Conceptual design of the tail research experiment at the Space Plasma Environment Research Facility(SPERF-TREX)

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Plasma Science and Technology 2024年第8期26卷 44-49页

作者：肖青梅毛傲华何向磊邹继同杨肖易孙萌萌李丰汤鹏飞周田春王晓钢 the SPERF Team Laboratory for Space Environment and Physical Sciences Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Physics Harbin Institute of TechnologyHarbin 150001People’s Republic of China Heilongjiang Provincial Key Laboratory of Plasma Physics and Application Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

The Space Plasma Environment Research Facility(SPERF)for ground simulation of the space plasma environment is a key component of the Space Environment Simulation Research Infrastructure(SESRI),a major national science and technology infrastructure for fundamental *** is designed to investigate outstanding issues in the space plasma environment,such as energetic particle acceleration,transport,and interaction with electromagnetic waves,as well as magnetic reconnection processes,in magnetospheric *** Tail-Research EXperiment(TREX)is part of the SPERF for laboratory studies of space physics relevant to magnetic reconnection,dipolarization and hydromagnetic wave excitation in the *** is designed to carry out three types of experiments:the tail plasmoid for magnetic reconnection,dipolarization front formation,and magnetohydrodynamic waves excited by highspeed plasma *** this paper,the scientific goals and three scenarios of SPERF-TREX for typical processes in space plasmas are presented,and experimental plans for SPERF-TREX are also reviewed,together with the plasma sources applied to generate the plasma with the desired parameters and various magnetic configurations.

关键词： SPERF-TREX wave-particle interaction magnetic reconnection dipolarization

Self-cleaning SERS sensor based on flexible Ni_(3)S_(2)/MoS_(2)@Ag@PDMS composites for label-free multiplex volatile organic compounds detection

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Nano Research 2024年第6期17卷 5529-5539页

作者： Xinyue Song Yongzheng Zhang Xiaohui Ren Dongyan Tang Xuelin Zhang Xin Li MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringState Key Lab of Urban Water Resource and EnvironmentHarbin Institute of TechnologyHarbin 150090China College of Textile and Clothing Yancheng Institute of TechnologyYancheng 224051China MEMS Center Harbin Institute of TechnologyHarbin 150001China

Flexible self-cleaning surface-enhanced Raman scattering(SERS)sensors are highly desirable for the detection of various environmental pollutants,including volatile organic compounds(VOCs).However,achieving sensitive detection without labeling and ensuring efficient cyclic use remain significant ***,we introduce a direct approach to create a versatile Ni_(3)S_(2)/MoS_(2)@Ag@PDMS(PDMS=polydimethylsiloxane)composite SERS substrate using chemical vapor deposition *** produced substrate shows outstanding performance,offering extremely low detection sensitivity(1.0×10^(−12)M 4-aminobenzenethiol)and high enhancement factors(approximately 107).The interactions between the rod-shaped Ni_(3)S_(2)/MoS_(2)@Ag heterostructure and the molecules facilitate the transfer of charge,resulting in an increased electric field enhancement of the exciton *** has the dual benefit of providing a self-cleaning effect and enhancing SERS ***,the substrate enables sensitive detection of VOCs gas molecules without the need for labels,achieving a minimum detectable concentration as low as 1 ppm for o-dichlorobenzene,due to the preconcentration effect of *** calculations further explain the combined effect of electromagnetic and chemical enhancement in this composite *** utilizing the developed visual SERS barcode,quick multiple detection and analysis of mixtures can be *** flexible and versatile SERS technique has significant potential for on-site detection and analysis of environmental pollutants,opening the doors for the development of a wearable in-situ SERS sensing platform.

关键词： surface-enhanced Raman scattering(SERS) quantitative detection recyclable detection volatile organic compounds(VOCs) chemical vapor deposition(CVD)

The Absorbing Properties of Two-Dimensional Plasma Photonic Crystals

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Plasma Science and Technology 2015年第1期17卷 4-9页

作者：亓丽梅李超方广有高翔 Key Laboratory of electromagnetic Radiation and Sensing Technology Institute of ElectronicsChinese Academy of Sciences

Plasma photonic crystals composed of periodic plasma and dielectric materials have attracted considerable attention because of their tunable photonic band gaps,but only their band structures or negative refractive index properties have been addressed in previous *** this paper,through studying the transmission and reflection characteristics of two types of twodimensional plasma photonic crystals,it is found that plasma photonic crystals play an important role in absorbing waves,and they show broader band and higher amplitude absorption characteristics than bulk ***,the absorption of plasma photonic crystals can be tuned via plasma parameters;varying the collision frequency can make the bandwidth and amplitude tunable,but cannot change the central frequency,whereas varying the plasma frequency would control both the location and the amplitude of the *** features of plasma photonic crystals have potential for terahertz tunable absorber applications.

关键词： plasma photonic crystal absorber tunable plasma frequency collision frequency

Negative Index Refraction in the Complex Ginzburg-Landau Equation in Connection with the Experimental CIMA Reaction

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Chinese Physics Letters 2012年第9期29卷 110-113页

作者： YUAN Xu-Jin electromagnetic Scattering Key laboratory Beijing Institute of Environmental CharacteristicsBeijing 100854

In comparison with the phenomenon of negative index refraction observed in artificial meta-materials,it is interesting to ask if this type of behavior also exists or not in reaction-diffusion systems that support nonlinear chemical *** studies indicate that the negative index refraction could occur on a interface between a medium of a normal wave and a medium that supports *** we investigate the phenomenon in the complex Ginzburg–Landau equation(CGLE)in a close relationship with the quantitative model for the chlorite-iodide-malonic acid(CIMA)*** amplitude equation CGLE is deduced from the CIMA reaction,and simulations with mapped parameters from the reaction-diffusion equation reveal that the competition between normal waves and anti-waves on the interface determines whether the negative index refraction occurs or not.

关键词： reaction. refraction Landau

Method for Evaluating Digital Video electromagnetic Information Leakage from Video Cable

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Chinese Journal of Electronics 2021年第5期30卷 978-985页

作者： WANG Sen QIU Yang TIAN Jin AECC Aero Engine Control System institute electromagnetic Compatibility Laboratory Xidian University

electromagnetic emissions from electrical information equipment may contain useful information and lead to information leakage. In order to detect the electromagnetic information leakage of digital video cable,a rapid testing method for computer video information leakage detection without reconstructing the displayed image is proposed. In this method, the electromagnetic radiation spectrum of typical image transmitted by HDMI cable is simulated. Then the electromagnetic radiation spectrum of the computer when transmitting the same image as the typical image is obtained by conduction and radiation EMC test methods. Finally, the correlation between the spectrum of simulation and the test spectrum is analyzed, and the correlation coefficient is used to judge whether the computer has produced the electromagnetic leakage of video information. The analysis and test results show that when the correlation coefficient is greater than 0.5, the electromagnetic leakage of computer video information can be judged.

关键词： electromagnetic compatibility and interference Radio and television broadcasting Information security Compromising emanation electromagnetic leakage Digital video information

A deterministic method study of the impact of the Pauli principle in double-gate MOSFETs

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Chinese Physics B 2012年第11期21卷 523-527页

作者：赵凯 Christoph Jungemann 刘晓彦 institute of Microelectronics Peking University Chair of electromagnetic Theory RWTH Aachen University

The Pauli principle is included in a multisubband deterministic solver for two-dimensional devices without approx- imations. The nonlinear Boltzmann equations are treated properly without compromising on accuracy, convergence, or CPU time. The simulation results indicate the significant impact of the Pauli principle on the transport properties of the quasi-2D electron gas, especially for the on state.

关键词： Pauli principle two-dimensional MOSFET degeneracy Fourier harmonics expansion