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Energy efficient design for multiuser downlink energy and uplink information transfer in 5G

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Science China(Information Sciences) 2016年第2期59卷 74-81页

作者： Chunguo LI Yanshan LI Kang SONG Luxi YANG Key Laboratory of Underwater Acoustic Signal Processing of Ministry of Education Southeast University ATR National Key Laboratory of Defense Technology Shenzhen University

Simultaneous wireless information and power transfer(SWIPT) is studied in this paper for the wireless powered downlink(DL) and multiuser information uplink(UL) systems. The objective is to maximize the energy efficiency defined as the ratio of the achieved throughput over the energy cost by optimizing the time allocation for the DL and multi-user UL traffics and its goal is to obtain the analytical expression to the optimal time allocation yet the resulting difficulty comes from the sum throughput of the multiuser in UL as well as the corresponding power consumption. To tackle this, the Jensen inequality is applied to approximating the exact expression of the sum throughput for the UL multi-users, leading to an upper-bound of the *** final closed form is exact in the single-user scenario yet approximate in the multi-user scenario. Numerical simulations verify the tightness of this approximation and the performances of the proposed analytical scheme.

关键词： energy harvest time allocation energy efficiency uplink multiuser throughput maximization analytical expression

Impact of Wind on Tide-Induced Advective Salt Transport in A Well- Mixed Estuary

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China Ocean Engineering 2021年第1期35卷 107-122页

作者： CHEN Wei-lun ZHU Yu-liang KONG Jun CHU Ao ZHANG Wei-sheng State Key Laboratory of Hydrology Water Resources and Hydraulic EngineeringHohai UniversityNanjing 210098China Key Laboratory of Coastal Disaster and Defence of Ministry of Education Hohai UniversityNanjing 210098China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Key Laboratory of the Pearl River Estuarine Dynamics and Associated Process Regulation Ministry of Water ResourcesGuangzhou 510610China Faculty of Civil Engineering and Geosciences Section of Hydraulic EngineeringDelft University of Technology2600 GA DelftThe Netherlands

The tide-induced net advective salt flux in well-mixed estuaries consists of five terms according to the method from *** term resulted from the vertical variation in salinity can be negligible in well-mixed estuaries with four tide-induced salt flux terms,known as F1−*** explore the effects of wind on these salt fluxes,the current-salinity analytical model combined with the perturbation analysis is extended by including *** expressions for the four salt fluxes are derived separately in the present *** the assumption that only the M_(2) tidal component is accounted for and the salt flux generated by diffusion is not studied,the tide-induced net advective salt flux Q_(sx) is in the seaward direction without the wind *** applying the Western Scheldt estuary case,the wind influence on the tidal advection salt flux(TASF)distribution in the F4 term was *** phase difference between zero-order velocity and first-order salinity(Δφ)at the surface layer of the estuary is larger than 90°and smaller than 90°at the bottom layer,which leads to landward TASF in the surface layer and seaward TASF in the bottom *** distribution ofΔφis not uniform in the horizontal direction with wind included,which differs from the result without *** the case of seaward wind with the speed of 18 m/s,the decrease in the zeroth-order velocity phase(φu)at the surface layer is larger than that of the first-order salinity phase(φs)downstream,which leads to an abnormal seaward TASF in this *** to the surface stress caused by wind,the Stokes compensation flow in the middle and lower reaches increases/decreases with the increase of the landward/seaward wind,while the upstream situation is ***,the first-order velocity in the middle and lower reaches increases/decreases with the increase of the landward/seaward wind,while the upstream situation is also *** first-order salinity also increases/decreases with the increase of la

关键词： tide-induced net advective salt flux analytical expression wind effect well-mixed estuary Western Scheldt Estuary

Application of generalized impedance boundary conditions to sommerfeld half-space problem

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Journal of Harbin Institute of Technology(New Series) 2005年第2期12卷 179-183页

作者：江滨浩刘永坦 Dept. of Electrical Engineering Harbin Institute of Technology Harbin 150001China Research Institute of Electronic Engineering Harbin Institute of Technology Harbin 150001China

Generalized impedance boundary conditions are employed to simplify the solution of the Sommerfeld half-space problem. An analytical expression is derived for the Hertz potential of a vertical electric dipole over the earth’s surface, in which the earth is assumed to be a layered media or homogeneous dissipative half-space. A Sommerfeld type integral in the potential function is expressed as the sum of two parts: a zeroth order Hankel function and an absolutely convergent series of Bessel functions. In addition, two expressions in closed form are obtained as the far-field and near-field approximation of the present result.

关键词： electromagnetic theory sommerfeld type integral generalized impedance boundary conditions analytical expression

Toeplitz周期三对角矩阵特征值的快速算法

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高等学校计算数学学报 2015年第3期37卷 193-202页

作者：唐达上海电机学院数理教学部

1引言矩阵称为Toeplitz周期三对角矩阵.如果α;=c;=0,则矩阵T退化为Toeplitz三对角矩阵.Tpeplitz三对角矩阵的特征值无论在理论上或实际上都有广泛的应用.该矩阵特征值可以用解析公式表示[1],但Toeplitz周期三对角矩阵的特征值却不能用... 详细信息

1引言矩阵称为Toeplitz周期三对角矩阵.如果α;=c;=0,则矩阵T退化为Toeplitz三对角矩阵.Tpeplitz三对角矩阵的特征值无论在理论上或实际上都有广泛的应用.该矩阵特征值可以用解析公式表示[1],但Toeplitz周期三对角矩阵的特征值却不能用解析公式表达,只能用数值计算求出.求周期三对角矩阵的特征值不仅是数学理论上的问题,它也有实际应用.例如用差分法解周期边界条件微分方程的特征值问题时,就要计算周期三对角矩阵

关键词： Toeplitz periodic tridiagonal matrix eigenvalue determinant search method analytical expression

The Transient Solution of Plane Progressive Waves

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China Ocean Engineering 1993年第3期8卷 305-312页

作者： Dai Yishan He Wuzhou Professor, Harbin Shipbuilding Engineering Institute, Harbin 150001 Associate Professor, Harbin Shipbuilding Engineering Institute, Harbin 150001

Generated by an ideal sinusoidal motion of the vertical plate, the simplest linear solution in time domain for two-dimensional regular waves is derived. The solution describes the propagation process of the plane progressive wave with a front, and will approach the linear steady- state solution as the oscillation time of the plate approaches infinity. The solution presented in this paper can be used to provide an incident wave model with analytical expression for solving the problems of diffraction and response of floating bodies in time domain.

关键词： plane progressive wave linear solution time domain analytical expression

Study on Electrical Potential by Buried Source Electrode within the Horizontally Layered Half-space Model

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Earthquake Research in China 2010年第2期24卷 167-178页

作者： Nie Yong＇an Yao Lanyu Earthquake Administration of Tianjin Municipality Tianjin 300201 China

The paper first studies the analytical expression of electrical potential by a point current source in a uniform half-space medium,and then focuses on the distribution of electrical potential in a horizontally layered half-space model by a point current source within the surface layer or the bottom ***,the electrical potential by a source electrode in any layer of a layered half-space model is presented.

关键词： Buried current electrode Horizontally layered half-space Electrical potential analytical expression