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Chinese Physics Letters 2012年第6期29卷 227-230页

作者： SU Wei LOU Shu-Qin YIN Guo-Lu School of electronic and Information engineering Beijing Jiaotong UniversityBeijing 100044

Structural properties and thermodynamic properties of amorphous SiO_(2)(a-SiO_(2)) and amorphous SiO_(2) with an oxygen defect ceuter (a-SiO_(2)-ODC) are investigated by using interatomic pair *** configurations of SiO_(2) glass are constructed by quenching using the molecular-dynamics method and subsequent relaxation using the first-principles *** numerical result demonstrates that the calculated short-range structural parameters coincide well with the previous experimental and theoretical results *** thermodynamic properties including specific heat,Debye temperature,vibrational entropy,and so on are analyzed by calculating the phonon ***,mechanical properties of both structures are obtained.

关键词： amorphous thermodynamic Oxygen

Improved two-way satellite time and frequency transfer with Multi-GEO in BeiDou navigation system

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Science China(Information Sciences) 2014年第2期57卷 169-183页

作者： YANG WenKe GONG Hang LIU ZengJun LI YuanLing SUN GuangFu College of electronic Science and engineering National University of Defense Technology

Due to the limitation of Geostationary Earth Orbit(GEO)satellite resources,only very few TWSTFT links with parallel counterpart operating via diferent GEO satellites between two ground stations are *** are 5 GEO satellites in BeiDou Navigation System,which enables an improved TWSTFT with *** algorithms are put forward to take the advantage of Multi-GEO links to improve the performance of time and frequency transfer *** dynamic weight average algorithm based on a newly proposed dynamic time variance aiming at improving the performance of time transfer is shown to be able to reduce the dynamic time deviation of the two-way measurement result to 1/√N dynamic time deviation of the single link using N-GEO links,if each link has similar level of link *** algorithm of cancelling out the link noise Allan variances with 2-GEO links is expected to obtain the Allan variance of clock diference between two ground *** experiment results using 2-GEO links in BeiDou Navigation System show that the dynamic weight average algorithm can improve the dynamic time deviation of the two-way measurement to around 0.6 of that of the single link in an average *** the estimated Allan deviation of the clock diference using the algorithm for cancelling the noise Allan variances of both links can reach 7×10 12(τ0.65)for the averaging time 1–105s which is within the same order of magnitude as the estimated Allan deviation based on carrier Doppler measurement for the averaging time 10 s–104s,despite the noisy links with the Allan deviation follows 3×10 10(τ1).

关键词： TWSTFT Multi-GEO BeiDou navigation system dynamic time variance dynamic weight average link noise Allan variance cancelling

Communication and monitor of breast cancer signal in the pulse-output genetic circuit network

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Science China(Information Sciences) 2014年第3期57卷 66-75页

作者： WANG Xiang YUAN GuangQian WANG Xun ZHAO ZeXi WANG Kan School of electronic and Information engineering Beihang University Carleton College

Pulse-output genetic circuit networks have the advantages in stability and *** this paper,we analyze some important parameters in a typical inverter,and then design a pulse-output genetic circuit of breast cancer signal communication and monitor of breast cancer *** first design a single-index monitor *** a certain tumor marker’s concentration exceeds the positive criterion,the circuit will output a pulse as a *** the diagnose results derived from one single tumor marker are sometimes indeterminate,an integrated circuit is proposed to construct a multi-index monitor circuit *** multi-index detection can strongly increase the correct recognition rate in terms of accuracy and *** circuit network may also be used in other fields of gene diagnosis with some modifications,and some experiments designed to validate them had been done.

关键词： genetic circuit network pulse multi-index breast cancer signal communication

Improved Method of Contention-Based Random Access in LTE System

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Journal of electronic Science and Technology 2018年第2期16卷 175-183页

作者： Han-Song Su Min Zhang Gao-Hua Liu School of electronic and Information engineering Tianjin UniversityTianjin 300072

Random access is the necessary process to establish the wireless link between the user equipment （UE） and network. The performance of the random access directly affects the performance of the network. In this work, we propose a method on the basis of the existing alternatives. In this method, we estimate the system load in advance to adjust the number of terminals. An access threshold is set to control the number of terminals which want to access the base station at an acceptable level. At the same time, we havean improvement on the existing power climbing strategy. We suppose that the power ramping is not always necessary for the re-access. And the selection ofpower ramping steps is studied in this paper. Simulations based on MATLAB are employed to evaluate the effectiveness of the proposed solution and to make comparisons with existing alternatives.

关键词： Access threshold long-term evolution(LTE) power ramping steps random access

Experimental research on air film formation behavior of air cushion belt conveyor with stable load

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Science China(Technological Sciences) 2013年第6期56卷 1424-1434页

作者： GUO Sheng LIU Jian LI ZhiRen ZHANG DongLi HUANG Wei School of Mechanical Electronic and Control EngineeringBeijing Jiaotong University

In this paper, the air film formation behavior of air cushion belt conveyor with stable load is studied. The air cushion field is analyzed by means of theoretical derivation, numerical simulation and experimental research. An intelligent experiment platform is developed. Three dimensional pressure distribution of air film and the air film thickness distribution along the conveyor belt in the width direction are obtained. The experimental result is analyzed by comparing with theoretical calculation and numerical simulation. The numerical and theoretical results are in good agreement with those obtained from experiments. The air film formation behavior pattern of air cushion belt conveyor with stable load is presented. The optimized film thickness and pore distribution are obtained based on the comprehensive energy consumption. This study provides a basis for the optimization design of air cushion belt conveyor.

关键词： air cushion belt conveyor stable load air film formation behaviour energy consumption analysis

Dynamical behaviour of an epidemic on complex networks with population mobility

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Chinese Physics B 2009年第9期18卷 3639-3646页

作者：张海峰 Small Michael 傅新楚汪秉宏 department of Modern Physics University of Science and Technology of China School of Mathematical Science Anhui University department of electronic and Information engineering Hong Kong Polytechnic University department of Mathematics Shanghai University

In this paper, we study the dynamical behaviour of an epidemic on complex networks with population mobility. In our model, the number of people on each node is unrestricted as the nodes of the network are considered as cities, communities, and so on. Because people can travel between different cities, we study the effect of a population＇s mobility on the epidemic spreading. In view of the population＇s mobility, we suppose that the susceptible individual can be infected by an infected individual in the same city or other connected cities. Simulations are presented to verify our analysis.

关键词： complex network mobility heterogeneity epidemic threshold

An LDPC coded cooperative MIMO scheme over Rayleigh fading channels with unknown channel state information

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Journal of Zhejiang University-Science C(Computers and electronics) 2013年第1期14卷 30-41页

作者： Shun-wai ZHANG Feng-fan YANG Lei TANG College of electronic and Information engineering Nanjing University of Aeronautics and Astronautics

This paper describes a coded cooperative multiple-input multiple-output(MIMO) scheme,where structured low-density parity-check(LDPC) codes belonging to a family of repeat-accumulate(RA) codes are *** outage probability of the scheme over Rayleigh fading channels is *** an unknown channel state information(CSI) scenario,adaptive transversal filters based on a spatio-temporal recursive least squares(ST-RLS) algorithm are adopted in the destination to realize receive diversity ***,a joint 'Min-Sum' iterative decoding is effectively carried out in the *** a decoding algorithm agrees with the bilayer Tanner graph that can be used to fully characterize two distinct structured LDPC codes employed by the source and *** results verify the effectiveness of the adopted filter in the coded cooperative MIMO *** analysis and numerical simulations show that the LDPC coded cooperative MIMO scheme can well combine cooperation diversity,multi-receive diversity,and channel coding gains,and clearly outperforms coded noncooperation schemes under the same conditions.

关键词： Cooperative multiple-input multiple-output (MIMO) Repeat-accumulate (RA) codes Bilayer Tanner graph Spatio-temporal recursive least squares (SToRLS) algorithm Joint 'Min-Sum' iterative decoding

Design of on-chip 15-18 GHz ultra low noise amplifier

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The Journal of China Universities of Posts and Telecommunications 2014年第4期21卷 15-18,31页

作者： GAO Yuan ZHANG Bao-jun ZHANG Bo School of electronic engineering Xi'an University of Posts and Telecommunications

With rapid development communication system, high signal to noise ratio （SNR） system is required. In high frequency bandwidth, high loss, low Q inductors and high noise figure is a significant challenge with on-chip monolithic microwave integrated circuits （MMICs）. To overcome this problem, high Q, low loss transmission line characteristics was analyzed. Compared with the same inductor value of the lumped component and the transmission line, it has a higher Q value and lower loss performance in high frequency, and a 2-stage common-source low noise amplifier （LNA） was presented, which employs source inductor feedback technology and high Q low loss transmission line matching network technique with over 17.6 dB small signal gain and 1.1 dB noise figure in 15 GHz-18 GHz. The LNA was fabricated by WIN semiconductors company 0.15 μm gallium arsenide （GaAs） P high electron mobility transistor （P-HEMT） process. The total Current is 15 mA, while the DC power consumption is only 45 mW.

关键词： LNA GAAS P-HEMT MMIC K-bAND

Electron trapping properties at HfO_2/SiO_2 interface, studied by Kelvin probe force microscopy and theoretical analysis

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Chinese Physics B 2016年第8期25卷 384-387页

作者：张满红 School of Electrical and electronic engineering North China Electric Power University

Electron trapping properties at the HfO2/SiO2 interface have been measured through Kelvin Probe force microscopy,between room temperature and 90 ℃.The electron diffusion in HfO2 shows a multiple-step *** injection,electrons diffuse quickly toward the HfO2/SiO2 interface and then diffuse laterally near the interface in two sub-steps：The first is a fast diffusion through shallow trap centers and the second is a slow diffusion through deep trap *** of contact potential difference profile in the fast lateral diffusion sub-step was simulated by solving a diffusion equation with a term describing the charge *** this way,the diffusion coefficient and the average life time at different temperatures were extracted.A value of 0.57 eV was calculated for the activation energy of the shallow trap centers in HfO2.

关键词： Kelvin probe force microscopy traps diffusion coefficient activation energy

Polarization resolved analysis of phonon transport in a multi-terminal system

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Chinese Physics B 2019年第12期28卷 208-214页

作者： Yun-Feng Gu Liu-Tong Zhu Xiao-Li Wu College of electronic and Mechanical engineering Nanjing Forestry UniversityNanjing210037China

The atomistic Green’s function method is improved to compute the polarization resolved phonon transport in a multiterminal system. Based on the recent developments in literature, the algorithm is simplified. The complex phonon band structure of a semi-infinite periodic terminal is obtained by the generalized eigenvalue equation. Then both the surface Green’s function and phonon group velocity in the terminal are determined from the wave modes propagating away from the scattering region along the terminal. With these key ingredients, the individual phonon mode transmittance between the terminals can be calculated. The feasibility and validity of the method are demonstrated by the chain example compared with the wave packet method, and an example of graphene nanojunction with three terminals.

关键词： Green’s function method phonon transport multi-terminal systems