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science china(Information sciences) 2011年第1期54卷 129-135页

作者： ZHOU ZhiQiang,LI ShaoQian & CHENG YuFan National Key Laboratory of science and technology on Communications,university of electronic science and technology of china,chengdu 610054.china 1. National Key Laboratory of science and technology on Communications University of Electronic Science and Technology of China Chengdu 610054 China

Fast frequency hopping can reduce the degradation caused by *** performance of noise-normalized fast frequency-hopped M-ary orthogonal frequency-shift-keying(FFH/MFSK)receivers over frequency nonselective Rayleigh fading channels with partial-band noise jamming is *** of numerical evaluation,a closed-form error probability expression is given based on the theory of complex variables. The simulation results validate the analytical *** is shown that there is an optimum diversity order and the system performance gets better with an increase in the modulation order.

关键词： anti-jamming fast frequency hopping noise normalization combining Rayleigh fading

THE TRANSIENT SOLUTION FOR M/G/1 QUEUEWITH SERVER VACATIONS

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Acta Mathematica Scientia 1997年第3期17卷 276-282页

作者：唐应辉 UNIV ELECT SCI & TECHNOL china DEPT MATH APPLCHENGDU 610054PEOPLES R CHINA

In this paper, the transient solutions for M/G/1 queues with single server vacation and multiple server vacations are firstly studied, and the recursion expressions of their Laplace transform are given. Further the distribution and stochastic decomposition result of the queue length at a random point in equilibrium are directly obtained from the transient solution. As will be seen this paper provides a intuitive and elegant method for studying transient solutions for M/G/1 queues with single server.

关键词： server-vacation queue length transient solution stochastic decomposition

Research and Development of Enterprise Information Visual Management System Based on GIS

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武汉理工大学学报 2006年第S1期28卷 339-343页

作者： YANG Liqing,LI Xunbo (school of Mechatronics engineering,university of electronic science and technology of china,chengdu 610054, china) school of Mechatronics engineering University of Electronic Science and Technology of ChinaChengdu 610054China

Aiming at managing enterprise information,we have done research and development on enterprise information visual management system based on geographic information system (GIS). In this paper,basis function,design scheme and implement are introduced. Space data and attribute data are supervised with a database. And the functions of GIS,such as display,edit and print,are utilized. The map information and the enterprise information are visually managed and integrally supervised.

关键词： GIS enterprise information management visualization

Genes for resistance to stripe rust on chromosome 2B and their application in wheat breeding

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Progress in Natural science:Materials International 2009年第1期19卷 9-15页

作者： Peigao Luo a,b,Xueyun Hu a,Huaiyu Zhang a,Zhenglong Ren a,b,a State Key Laboratory of Plant Breeding and Genetics,sichuan Agriculture university,Ya’an,sichuan 625014,china b school of Life science and technology,university of electronic science and technology of china,chengdu 610054.china [a]State Key Laboratory of Plant Breeding and Genetics Sichuan Agriculture University Ya’an Sichuan 625014 China [b]School of Life Science and Technology University of Electronic Science and Technology of China Chengdu 610054 China

Stripe rust,caused by Puccinia striiformis ***,is one of the most damaging diseases of wheat *** resistant cultivars is the most economic and environmental friendly way to control the *** are many resistance genes to stripe rust located on wheat chromosome ***,we propose a strategy to construct the recombinant wheat chromosome 2B with multiple resistances to stripe rust by making crosses between wheat lines or cultivars carrying Yr genes and using marker-assisted selection,based on the reported information about resistance spectrum,chromosomal location,and linked markers of the *** the resistance genes on 2B would afford a valuable strategy to control the disease by cultivating varieties with durable *** possibility,efficiency,and prospect of the suggested strategy are reviewed in the paper.

关键词： Puccinia striiformis Yr gene 2B chromosome Stripe rust Marker-assisted selection

Application of FSS to Reduction of Antennas' RCS

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Journal of Systems engineering and electronics 1996年第1期7卷 71-74页

作者： Feng Lin & Roan Yingzheng (university of electronic science and technology of china, chengdu 610054) university of electronic science and technology of china Chengdu 610054

It is an effective approach for reducing antennas'scattering to use frequency selective surface (FSS) as main reflector or *** measured results are given and discussed. In comparison with ordinary metallic refiector antenna, the FSS reflector antenna's radiation properties are maintained basically but its radar cross-section (RCS) is reduced significantly. FSS subrefiector can be more easily applied to practice, but has a little higher RCS level than that of FSS main reflector.

关键词： Reflector antenna Antenna scattering Frequency selective surface.

Microwave Hydrothermal Synthesis PZT of Nanometer Crystal

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Journal of Materials science & technology 2004年第5期20卷 637-638页

作者： Hongxing LIU, Hong DENG, Yan LI and Yanrong LIInstitute of Microelectronics and Solid State electronics, university of electronic science and technology of china, chengdu 610054, china Inst. of Microelectronics Univ. of Electron. Sci. and Technol. Chengdu 610054 China

It was focused on the applications and developments of microwave hydrothermal synthesis piezoelectric ceramic powder. The microwave hydrothermal vessel was designed and manufactured. The microwave hydrothermal synthesis system was established and the PZT piezoelectric ceramic powder was synthesized. XRD and TEM have been used to characterize the products in detail. The diameter of the PZT powder particle is from 40 to 60 nm.

关键词： Microwave hydrothermal synthesis Reaction vessel PZT

BDNF Meditated trkB and Synapsin I Changes within the Hippocampus after Mild Traumatic Brain Injury in Rat:Reflections of Injury-induced Neuroplasticity

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生物医学工程学杂志 2005年第S1期22卷 61-62,64页

作者： Yu-Bo CHEN Mei-Yun WU(school of Life science and technology, university of electronic science and technology of china, chengdu 610054, china)

Properties of nonadiabatic quantum fluctuations of the strongly coupled electron-phonon systems

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science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 258-268页

作者： PANG XiaoFeng Institute of Life science and technology,university of electronic science and technology of china,chengdu 610054.china International Centre for Materials Physics,Chinese Academy of sciences,Shenyang 110015,china Institute of Life science technology University of Electronic Science technology of china Chengdu 610054 China International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110015 China

A new variational-ansatz of states of electrons and phonons was proposed on the basis of the Holstein model in strongly coupled electron-phonon systems for studying the influence of nonadiabatic phonon fluctuation,arising from the motion and density fluctuation of electrons,on the properties of ground state,uncertainty relation,stability of polarons,charge density wave (CDW) and phonon staggered ordering. The new ansatz represents the correlation among the displacement and squeezing states of phonons and polaron’s state of electrons as well as the squeezing-antisqueezing effect. The correlation and squeezing-antisqueezing ef-fect result in the decrease of ground state energy,enhancement of stability of the systems,increase of binding energy of the polarons,weakening of the growing speed of polaron narrowing of the electron band,increase of the charge density wave order and suppression of the increased tendency of anomalous quantum fluctuation of the phonons in such a case,when compared with the uncorrelated case in the systems. The results obtained show that the ground state determined by the new state ansatz is most stable,thus the new ansatz describing the properties of the coupled electron phonon systems is very relevant and available,especially in strongly coupled and largely squeezed cases.

关键词： squeezing-antisqueezing effect state-ansatz polaron coupled electron-phonon systems quantum fluctuation

Magnetic Properties of Nanometer-Scale NiZnCu Ferrite Thin Films Fabricated by Spray-Spin-Heating-Coating Method

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Journal of Materials science & technology 2004年第1期20卷 35-37页

作者： Yulan JING, Huaiwu ZHANG, lijun JIA, Yu SHI and Yingli LIUInstitute of Information and Materials, university of electronic science and technology of china, chengdu 610054, china Inst. of Info. and Mat. Univ. of Electron. Sci. and Technol. Chengdu 610054 China

A new nanometer-scale ferrite thin film with excellent high-frequency characteristics has been developed by the spray-spin-heating-coating method. The effects of the ion synthesis mechanism, chemical stoichiometry, fabrication method, and doping content on the magnetic properties and microstructure of the thin films have been analyzed. The films formed between 75℃ and 90℃ by spray-spin-heating-coating methods was discovered with fine grain size of about 21 nm, high saturation magnetization (4πMs) of about 6.5 kGs, coercivity of about 9.8 Oe, as well as initial permeability of about 14.0. These films can be widely used in radio-frequency integrated circuit devices.

关键词： Nanometer materials Ferrite thin film Spray-spin-heating-coating

Analysis of forest backscattering characteristics based on polarization coherence tomography

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science china(Technological sciences) 2010年第S1期53卷 166-175页

作者： LUO HuanMin 1,LI XiaoWen 1,2,CHEN ErXue 3,CHENG Jian 4 & CAO ChunXiang 21 Institute of Geo-Spatial Information science and technology,university of electronic science and technology of china,chengdu 610054.china 2 State Key Laboratory of Remote Sensing science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of sciences and Beijing Normal university,Beijing 100101,china 3Institute of Forest Resources Information Technique of Chinese Academy of Forestry,Beijing 100091,china 4 school of electronic engineering,university of electronic science and technology of china,chengdu 610054.china State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Beijing Normal Univ Beijing 100101 Peoples R China Univ Elect Sci & Technol china Inst Geospatial Informat Sci & Technol Chengdu 610054 Peoples R China Chinese Acad Forestry Inst Forest Resources Informat Tech Beijing 100091 Peoples R China Univ Elect Sci & Technol china Sch Elect Engn Chengdu 610054 Peoples R China

It is difficult to make an inventory of vertical profiles of forest structure parameters in field ***,analysis and understanding of forest backscattering characteristics contribute to estimation and detection of forest vertical structure because of the close relationships between backscattering characteristics and structure *** vertical structure function in the complex interferometric coherence definition,which represents the vertical variation of microwave scattering with the penetration depth at a point in the 2-D radar image and can be used to analyze the forest backscattering characteristics,can be reconstructed from polarization coherence tomography(PCT).Based on PCT,the paper analyzes the forest backscattering characteristics and explores the inherent relationship between the result of PCT and the forest structure parameters from numerical simulation of Random Volume over Ground model(RVoG),Polarimetric SAR interferometry(PolInSAR)simulation of forest scene and PolInSAR data at L-band of the test site ***,the effects of the extinction coefficient and surface-to-volume scattering ratio in RVoG model on vertical backscattering characteristics are analyzed by means of numerical ***,by applying PCT to L-band POLInSAR simulations of forest scene,different variations of vertical backscattering due to different extinction coefficients and the ratios of surface-to-volume scattering resulting from different polarizations,forest types and densities are displayed and *** a concept of relative average backscattering intensity is presented,and the factors which affect its vertical distribution are also *** results show that there is high sensitivity of the vertical distribution of forest relative average backscattering intensity to the polarization,forest type and ***,based on repeat pass DLR E-SAR L-band airborne POLInSAR data,the capability of PCT technology for detection

关键词： backscattering characteristic POLInSAR PCT vertical structure function