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Computation of Dielectric Constants and Loss Tangents at ISM Band by Measurements of transmission coefficients

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The Journal of China Universities of Posts and Telecommunications 2003年第2期10卷 69-73页

作者： Y.E.Mohammed LIUYuan-an A.S.Abdallah WANGNan BeijingUniversityofPostsandTelecommunications Beijing100876P.R.China TelecommunicationMetrologyCenterofMII

The ISM band at 2.4 GHz has mostly been used or planned for indoor *** band is also attractive for outdoor systems owing to the ease of the system deployment, as nofrequency licenses are required. In this paper, a multiple successive internal multireflection modelis used to estimate the complex electric permittivity at 2.4 GHz band. To obtain the data,measurements are performed at 160 MHz bandwidth centered about 2. 4 GHz using a vector networkanalyzer, which provides information about the amplitude and phase of transmission *** samples of each material are measured and the results vary from sample to sample. It hasalso been found that some obstacles have polarization behaviour.

关键词： internal multi reflection model transmission coefficient

Experimental Research on A New Type of Floating Breakwater for Wave-Absorbing and Energy-Capturing

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China Ocean Engineering 2020年第6期34卷 817-827页

作者： HUANG Fang-ping GONG Kai LIU Zuo-shi CHEN Jun-hua HUANG Yan-chen School of Mechanical Engineering Zhejiang UniversityHangzhou 310027China Ningbo Institute of Technology Zhejiang UniversityNingbo 315100China School of Mechanical and Electrical Engineering Jiangxi University of Science and TechnologyGanzhouChina

To avoid the damage caused by big wind and wave in cage culture, and to solve the problem of energy supply faced by automatic breeding equipment, a new type of floating breakwater, named as Savonius double buoy breakwater(SDBB), is proposed in the paper. The floating breakwater is composed of HDPE cylindrical double buoys and horizontal axis Savonius rotors, and has the functions of wave-absorbing and energy-capturing. Based on the linear wave theory and energy conservation law, the Fourier Transform was applied to separate the two-dimensional wave frequency domain, and the energy captured by the rotors and absorbed by the floating breakwater were *** were conducted in a two-dimensional wave-making flume, and the transmitted waves at different wave heights and periods, the tension of mooring lines, and the rotational torque exerted on the Savonius rotor were measured. A series of performance comparison tests were also performed on the new floating breakwater and the traditional double-floating breakwater. Results show that the new floating breakwater is better than the traditional one in terms of reducing wave transmittance, and the combination of the floating breakwater with Savonius rotors can provide for marine aquaculture equipments with green power supply to a certain degree of self-sufficiency.

关键词： floating breakwater Savonius rotor transmission coefficient wave energy capturing mooring force

EXPERIMENTAL STUDY ON A NEW KIND OF OPEN TYPE BREAKWATERS

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Journal of Hydrodynamics 2005年第2期17卷 228-233页

作者： WANGGuo-yu WANGYong-xue LIGuang-wei StateKeyLaboratoryofCoastalandOffshoreEngineering DalianUniversityofTechnologyDalian116024China

A new kind of open type breakwaters was proposed based on the concept of wave energy conversion. The excellent feature of the structure is that it can absorb and utilize the wave energy to dissipate waves. The effects of some factors, such as the configuration insides, the geometrical parameters and the relative width (the ratio of the width to the wave length), on the performance of the breakwater were discussed based on a series of regular wave tests in the wave flume. The hydrodynamic characteristics of the new open type breakwater were analyzed in detail, and the structure was optimized to improve the performance of the breakwater to effectively dissipate the waves with long period. The variation of the coefficients of wave transmission and reflection along with attenuation with respect to relative width was examined. The results of the physical model tests indicate that the transmission coefficient significantly decreases by about twenty percent at the range of relative width from 0.1 to 0.2, compared with the traditional open type breakwaters.

关键词： open type breakwater wave energy conversion transmission coefficient physical model test

The analytical transfer matrix method for quantum reflection

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Chinese Physics B 2010年第4期19卷 56-61页

作者：许田曹庄琪方靖淮 Physics Department Nantong University Institute of Optics and Photonics Shanghai Jiao Tong University

In this paper, the analytical transfer matrix method （ATMM） is applied to study the properties of quantum reflection in three systems： a sech2 barrier, a ramp potential and an inverse harmonic oscillator. Our results agree with those obtained by Landau and Lifshitz [Landau L D and Lifshitz E M 1977 Quantum Mechanics （Non-relativistic Theory）（New York： Pergamon）], which proves that ATMM is a simple and effective method for quantum reflection.

关键词： analytical transfer matrix method quantum reflection reflection coemcient transmission coefficient reflection time

Analytical and Experimental Studies on Hydrodynamic Performance of Semi-Immersed Jarlan-Type Perforated Breakwaters

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China Ocean Engineering 2015年第6期29卷 793-806页

作者：刘勇姚卓琳李华军 Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of China

The present study proposes a new semi-immersed Jarlan-type perforated breakwater including a perforated front wall, a solid rear wall, and a horizontal perforated plate connecting the lower tips of the two walls. An analytical solution is developed to estimate the hydrodynamic performance of the new breakwater. The analytical solution is confirmed by solutions for special cases, an independently developed multi-domain boundary element method solution and experimental data. Numerical examples based on the analytical solution indicate that compared with previous semi-immersed breakwaters, the new breakwater may have better wave-absorbing performance and smaller wave forces. Some useful results are presented for practical designs of semi-immersed Jarlan-type perforated breakwaters.

关键词： semi-immersed breakwater analytical solution experimental test transmission coefficient reflection coefficient wave force

Spin transport properties in double quantum rings connected in series

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Journal of Semiconductors 2011年第2期32卷 1-5页

作者：杜坚王素新潘江洪 Department of Physics Hebei Normal College for Nationalities College of Physics and Technology Guangxi Normal University

A new model of metal/semiconductor/metal double-quantum-ring connected in series is proposed and the transport properties in this model are theoretically studied. The results imply that the transmission coefficient shows periodic variations with increasing semiconductor ring size. The effects of the magnetic field and Rashba spin-orbit interaction on the transmission coefficient for two kinds of spin state electrons are different. The number of the transmission coefficient peaks is related to the length ratio between the upper arm and the half circumference of the ring. In addition, the transmission coefficient shows oscillation behavior with enhanced external magnetic field, and the corresponding average value is related to the two leads＇ relative position.

关键词： transmission coefficient double quantum rings Rashba spin-orbit interaction

Numerical Investigations on Hydrodynamic Performance of An Open Comb-Type Breakwater Under Medium Water Levels

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China Ocean Engineering 2021年第6期35卷 866-877页

作者： FANG Zhuo CHENG Liang ZANG Zhi-peng SHEN Chen TIAN Ying-hui CHENG Ning Transport planning and Research Institute Ministry of TransportBeijing 100028China Laboratory for Traffic and Transport Planning Digitalization Beijing 100028China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116023China State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China Melbourne School of Engineering The University of MelbourneParkvilleVIC 3010Australia China Harbor Engineering Company Limited Beijing 100027China

The comb-type breakwater(CTB)has been proposed and investigated in recent years due to its advantages in terms of deep-water adaptability,material saving and water *** existing empirical formulae for CTBs have been so far restricted to the water level above the bottom of the superstructure,which mainly occurs under the high tides or storm ***,based on recent engineering applications and experimental observations,the most severe conditions for CTBs are more likely to occur under a medium water level,because impulsive wave pressure may occur due to interactions between waves and the special chamber in ***,during the most of construction and operation periods,the CTBs are mainly working under the medium water levels,i.e.,water levels below the bottom of the *** this study,the effects of main influence parameters on the horizontal wave force coefficient and wave transmission coefficient for open CTBs(with partially immersed side plates)under medium water levels were investigated based on a 3D numerical wave flume and corresponding empirical formulae were *** is indicated that the location of the side plate related to the main caisson has significant influence on the hydrodynamic performance of *** engineering applications,the location of the side plate can be designed at b/L≤0.15 or b/L≥0.3(where b is the distance between the side plate and the front face of the main caisson and L is the incident wave length)for efficiently lowering the horizontal wave force and wave *** flow mechanism of impulsive wave force on CTBs was revealed based on synchronous analyses of flow fields and pressure *** appropriate design of the height of the superstructure according to H/hD≤1.0 or H/hD≥1.5(where H is the incident wave height and hD is the distance between the still water level and the bottom of the superstructure),the likely impulsive wave pressure on the side plate can also be diminished.

关键词： numerical wave flume open comb-type breakwater horizontal wave force coefficient transmission coefficient medium water level

WAVE MOTION OVER TWO SUBMERGED LAYERS OF HORIZONTAL THICK PLATES

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Journal of Hydrodynamics 2009年第4期21卷 453-462页

作者： LIU Yong LI Yu-cheng TENG Bin Key Laboratory of Ocean Engineering Shandong Province Ocean University of China Qingdao 266100 China Key Laboratory of Water and Sediment Science and Water Hazard Prevention Hunan Province Changsha 410076 China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

This study investigates the hydrodynamic performance of a submerged two layer horizontal plate breakwater. The plate thickness is considered as non-zero in the study. In the context of linear potential theory, an analytical solution for interaction of water waves with the plates is obtained using the matched eigenfunction expansion method. The solution consists of a symmetric part and an antisymmetric part. Its validity is confirmed by comparing the numerical results of reflection and transmission coefficients for limiting cases with previous predictions. Numerical examples are given to examine the major factors that affect the reflection and transmission coefficients of the plates. Some useful results are presented for engineering design.

关键词： submerged breakwater horizontal thick plate reflection coefficient transmission coefficient

A Numerical Method for Calculating transmission coefficients Across Arbitrary Potential Barriers with High Accuracy

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Journal of Semiconductors 2008年第2期29卷 201-205页

作者：丁武昌徐学俊成步文左玉华余金中王启明中国科学院半导体研究所光电集成实验室北京100083

We report a new method for calculating transmission coefficients across arbitrary potential barriers based on the Runge-Kutta method. A numerical solution of the Schrodinger equation is calculated using the Runge-Kutta method,and a new model is established to analyze the numerical results to find the transmission coefficient. This technique is applied to various cases, such as parabolic potential barrier and double-barrier structures. transmission probability with high precision is obtained and discussed. The tunnelling current density through a MOS structure is also explored and the result coincides with the Fowler-Nordheim model,which indicates the applicability of our method.

关键词： transmission coefficient tunneling probability Runge-Kutta method