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Analysis of non-uniform hetero-gate-dielectric dual-material control gate TFET for suppressing ambipolar nature and improving radio-frequency performance

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Chinese Physics B 2019年第10期28卷 571-578页

作者：许会芳崔健孙雯韩新风 Institute of Electrical and Electronic Engineering Anhui Science and Technology University

A tunnel field-effect transistor(TFET) is proposed by combining various advantages together, such as non-uniform gate-oxide layer, hetero-gate-dielectric(HGD), and dual-material control-gate(DMCG) technology. The effects of the length of non-uniform gate-oxide layer and dual-material control-gate on the on-state, off-state, and ambipolar currents are investigated. In addition, radio-frequency performance is studied in terms of gain bandwidth product, cut-off frequency,transit time, and transconductance frequency product. Moreover, the length of non-uniform gate-oxide layer and dualmaterial control-gate are optimized to improve the on-off current ratio and radio-frequency performances as well as the suppression of ambipolar current. All results demonstrate that the proposed device not only suppresses ambipolar current but also improves radio-frequency performance compared with the conventional DMCG TFET, which makes the proposed device a better application prospect in the advanced integrated circuits.

关键词： non-uniform gate-oxide layer ambipolar current radio-frequency performances tunnel fieldeffect transistor

The Introduction of Specific Water and Maximum Airborne Specific Water &the Improvement of Dynamic Equations on non-uniform Saturated Moist Atmosphere

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Atmospheric and Climate Sciences 2015年第3期5卷 245-256页

作者： Xingrong Wang Yan Feng Anhui Key Lab of Atmospheric Science and Satellite Remote Sensing Anhui Meteorology Institute Hefei China

To eliminate the irrational supposition that condensed liquid water always falls immediately, specific water m?and maximum airborne specific water mm are introduced into the dynamic framework on non-uniform saturated moist atmosphere (m?is the ratio of the airborne liquid water mass to the moist air mass in unit cubage moist air, mm is its maximum value with , , and are airborne coefficient, vertical velocity and saturated specific humidity respectively). The balance equation between water vapor and airborne liquid water is derived. From the balance equation, a new formula of precipitate rate is got. The analysis shows that in the air stream with some upward vertical velocity ( ), the condensed liquid water can precipitate under the condition with (q is specific humidity) and? only, otherwise it is detained in the air and becomes airborne liquid water. Not only does precipitating liquid water contain condensed liquid water, but also contains converged and existing airborne liquid water. Following above discussion, improved dynamic equations on non-uniform saturated moist atmosphere are provided.

关键词： Airborne Liquid Water Specific Water Maximum Airborne Specific Water Airborne Coefficient Dynamic on non-uniform Saturated Moist Atmosphere

Boundary Layer Flow of an Unsteady Dusty Fluid and Heat Transfer Over a Stretching Sheet with non-uniform Heat Source/Sink

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Engineering（科研） 2011年第7期3卷 726-735页

作者： Bijjanal J. Gireesha Govinakovi S. Roopa Channabasappa S. Bagewadi 不详

An analysis has been carried out to study the effect of hydrodynamic laminar boundary layer flow and heat transfer of a dusty fluid over an unsteady stretching surface in the presence of non-uniform heat source/sink. Heat transfer characteristics are examined for two different kinds of boundary conditions, namely 1) variable wall temperature and 2) variable heat flux. The governing partial differential equations are transformed to system of ordinary differential equations. These equations are solved numerically by applying RKF-45 method. The effects of various physical parameters such as magnetic parameter, dust interaction parameter, number density, Prandtl number, Eckert number, heat source/sink parameter and unsteadiness parameter on velocity and temperature profiles are studied.

关键词： Unsteady Flow Heat Transfer Boundary Layer Flow Stretching Surface Dusty Fluid Fluid-Particle Interaction Parameter and non-uniform Heat Source/Sink

Study of the non-uniform Distribution of Earthquake Risk Within Potential Sources

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Earthquake Research in China 1997年第1期11卷 71-77页

作者： Xu Guangyin and Gao MengtanInstitute of Geophysics,SSB,Beijing 100081,China

Potential sources are aggregates of probable future epicenters.In this area,for source models currently,in common use for seismic risk analysis in China,the mean area of each potential source is about 3000-4000 km2.It is assumed that seismic risk has a uniform distribution within the range of each potential source,but studies have shown that the uniform distribution model to a large extent may give an underestimation of the seismic risk.In this paper,the relative distribution of historical epicenters in space within potential sources is discussed,a method is proposed to quantitatively describe the non-uniform distribution of strong earthquakes within potential sources,and some preliminary results are given.By using the results of this paper,seismic risk analysis and seismic zonation can be made more scientific and more reasonable.

关键词： spatial relative distribution non-uniform distribution potential source seismic hazard analysis

Inverse approach to determine piston profile from impact stress waveform on given non-uniform rod

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中国有色金属学会会刊：英文版 2001年第2期11卷 297-300页

作者：朱萍玉刘德顺彭佑多陈安华湘潭工学院机械系振动、冲击与诊断所湖南湘潭 411201

An essential problem in the design of mechanical impact systems is the impact of a piston on a rod. The impact of a semi finite cylindrical piston on a non uniform rod was studied. Based on wave mechanics and characteristic line theory, an inverse numerical approach to determine the piston profile was proposed, by means of which the geometry of an impact piston may be determined from the given stress waveform for a given rod profile. Numerical results show that the given stress waveform may be produced by means of the alternatives of design of piston and rod. There is good agreement between the experimental results and numerical results. [

关键词： impact piston profile non-uniform rod inverse numerical approach stress waveform

Effect of non-uniform Basic Temperature Gradient on the Onset of Rayleigh-Bénard-Marangoni Electro-Convectionin a Micropolar Fluid

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Applied Mathematics 2013年第8期4卷 1180-1188页

作者： Thadathil Varghese Joseph Sree Ramaiah Manjunath Subbarama Pranesh Department of Mathematics BNMIT Bangalore India Department of Mathematics Christ University Bangalore India

The effects of electric field and non-uniform basic temperature gradient on the onset of Rayleigh-Bénard-Marangoni convection in a micropolar fluid are studied using the Galerkin technique. The eigenvalues are obtained for an upper free/adiabatic and lower rigid/isothermal boundaries. The microrotation is assumed to vanish at the boundaries. A linear stability analysis is performed. The influence of various micropolar fluid parameters and electric Rayleigh number on the onset of convection has been analysed. Six different non-uniform temperature profiles are considered and their comparative influence on onset is discussed.

关键词： Rayleigh-Bénard-Marangoni non-uniform Temperature Gradient Electric Field Micropolar Fluid Galerkin Technique

non-uniform FFT and Its Applications in Particle Simulations

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Applied Mathematics 2014年第3期5卷 520-541页

作者： Yong-Lei Wang Fredrik Hedman Massimiliano Porcu Francesca Mocci Aatto Laaksonen Department of Materials and Environmental Chemistry Arrhenius Laboratory Stockholm University Stockholm Sweden Department of Materials and Environmental Chemistry Arrhenius Laboratory Stockholm University Stockholm Sweden Dipartimento di Scienze Chimiche e Geologiche Cagliari University Cittadella Universitaria di Monserrato (CA) Monserrato Italy Noruna AB Stockholm Sweden

Ewald summation method, based on non-uniform FFTs (ENUF) to compute the electrostatic interactions and forces, is implemented in two different particle simulation schemes to model molecular and soft matter, in classical all-atom Molecular Dynamics and in Dissipative Particle Dynamics for coarse-grained particles. The method combines the traditional Ewald method with a non-uniform fast Fourier transform library (NFFT), making it highly efficient. It scales linearly with the number of particles as , while being both robust and accurate. It conserves both energy and the momentum to float point accuracy. As demonstrated here, it is straight- forward to implement the method in existing computer simulation codes to treat the electrostatic interactions either between point-charges or charge distributions. It should be an attractive alternative to mesh-based Ewald methods.

关键词： Ewald Summation Method non-uniform Fast Fourier Transform Dissipative Particle Dynamics

Skin Temperature and Body Surface Section in non-uniform and Asymmetric Outdoor Thermal Environment

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Health 2018年第10期10卷 1321-1341页

作者： Yoshihito Kurazumi Kenta Fukagawa Tomonori Sakoi Ariya Aruninta Emi Kondo Ken Yamashita School of Life Studies Sugiyama Jogakuen University Nagoya Japan Department of Architecture Kyushu Sangyo University Fukuoka Japan Academic Assembly Institute of Textile Science and Technology Shinshu University Nagano Japan Department of Landscape Architecture Chulalongkorn University Bangkok Thailand Department of Architecture Ariake National College of Technology Omuta Japan

In indoor environments and shady outdoor environments, there is little influence of short-wavelength solar radiation, so a strikingly non-uniform and asymmetric environment is not formed. In outdoor sunny environment, however, shaded areas occur even for the same site of the body, and a remarkable difference in skin temperature is considered to occur under the influence of the short-wavelength solar radiation. The purpose of this study is to clarify the influence of the non-uniform and asymmetric thermal radiation of short-wavelength solar radiation in outdoor environment on the division of the body surface section and the calculation of the mean skin temperature. The skin temperature of the front of the coronal surface, which was facing the sun and where the body received direct short-wavelength solar radiation, and the skin temperature of the rear of the coronal surface, which was in the shadow and did not receive direct short-wavelength solar radiation were respectively measured. The feet, upper arm, forearm, hand and lower leg, which are susceptible to short-wavelength solar radiation in a standing posture, had a noticeable difference in skin temperature between sites in the sun and in shade. The mean skin temperature of sites facing the sun was significantly higher than the mean skin temperature of those in the shade.

关键词： Asymmetry Mean Skin Temperature non-uniform Outdoor Environment Physiological Response Skin Temperature Solar Radiation

Cosine Modulated non-uniform Filter Banks

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Journal of Signal and Information Processing 2011年第3期2卷 178-183页

作者： Jyotsna Ogale Samrat Ashok 不详

Traditional designs for non-uniform filter bank (NUFB) are usually complex;involve complicated nonlinear optimization with a large number of parameters and lack of linear phase ([LP) property. In this paper, we describe a simple design method for multirate near perfect reconstruction (NPR) cosine modulated filter banks with non-uniform frequency spacing and linear phase property that involves optimization of only single parameter. It is derived from the uniform cosine modulated filter bank (CMFB) by merging some relevant band pass filters. The design procedure and the structure of the uniform CMFB are mostly preserved in the non-uniform implementation. Compared to other design methods our method provides very good design and converges very rapidly but the method is applicable, only if the upper band edge frequency of each non-uniform filter is an integral multiple of the bandwidth of the corresponding band. The design examples are presented to show the superiority of the proposed method over existing one.

关键词： Cosine Modulation Merging non-uniform Filter Bank Near Perfect Reconstruction