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In flight MTF monitoring and compensation for CCD camera on CBERS-02

science china(Technological sciences) 2005年第S2期48卷 29-43页

作者： GU Xingfa1,2,3, LI Xiaoying1,2,4, MIN Xiangjun5, YU Tao1,2, SUN Jijuan5, ZENG Yong1,2,4, XU Hua1,2 & GUO Ding2,6.1. 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 2. The Center for National Spaceborne Demonstration, Beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. Graduate university of Chinese Academy of sciences, Beijing 100039, china 5. china Center for Resource Satellite Data and Application, Beijing 100830, china 6. university of electronic science and technology of china, chengdu 610054, china 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 The Center for National Spaceborne Demonstration

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5 for 45° directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 45° axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.

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Special Issue for the 50th Anniversary of the Founding of university of electronic science and technology of china

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Journal of electronic science and technology of china 2006年第3期4卷 I0001-I0002页

作者： Journal of electronic science and technology of china

The special issue of this Journal has been organized for the celebration of the 50th anniversary of the founding of university of electronic science and technology of china （UESTC）.

关键词： Special Issue for the 50th Anniversary of the Founding of university of electronic science and technology of china

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The analyticity of solutions to a class of degenerate elliptic equations

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science china Mathematics 2010年第8期53卷 2061-2068页

作者： LI ChunHe School of Mathematical science,university of electronic science and technology of china,{6. 610054,china School of Mathematical science University of Electronic Science and Technology of China

In the present paper,the analyticity of solutions to a class of degenerate elliptic equations is obtained.A kind of weighted norms are introduced and under such norms some degenerate elliptic operators are of weak coe... 详细信息

关键词： analyticity degenerate elliptic equations weighted norm weak coerciveness

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A regularization method in the electromagnetic inverse scattering problem

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Progress in Natural science:Materials International 2007年第3期17卷 346-351页

作者： XIONG Xiaoyun, ZHAO Yanwen and NIE Zaiping (School of electronic Engineering, university of electronic science and technology of china,{6., china) School of electronic Engineering University of Electronic Science and Technology of China Chengdu 610054 China

Based on the normalization of measurement data equations of the inverse scattering problem, a new regularization matrix is proposed. It can eliminate the unfavorable effects caused by difference of distances between field-point or source-point and target region, reduce the loss of useful information in regularization procedure, and decrease condition numbers of the ill-posed problems. Inversion for conductivity distribution of two-dimensional axisymmetric inhomogeneous media is carried out by combing this new regularization method with distorted Born iterative method. Simulation results show that compared with the conventional method, the new regularization method is of better stability, quicker convergence, higher accuracy of inversion and higher resolution.

关键词： inverse scattering regularization distorted Born iterative method.

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Performance analysis of a noise-normalized FFH/MFSK receiver over Rayleigh fading channels with partial-band noise jamming

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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{6.,chengdu 610054,china National Key Laboratory of science and technology on Communications University of Electronic Science and Technology of 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

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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 Department of Applied Mathematics University of Electronic Science and Technology of China Chengdu 610054 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

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Effects of pH on the peripheral light-harvesting antenna complex for Rhodopseudomonas palustris

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science china(Life sciences) 2008年第8期51卷 760-766页

作者： FENG Juan, LI XueFeng & LIU Yan School of Life science and technology, university of electronic science and technology of{6., chengdu 610054,{6. School of Life science and technology University of Electronic Science and Technology of China Chengdu China

In this work steady-state absorption spectroscopy, circular dichroism spectroscopy and sub-micro-second time-resolved absorption spectroscopy were used to investigate the effect of pH on the struc-tures and functions of LH2 complex for Rhodopseudomonas palustris. The results revealed that: (1) B800 Bchla was gradually transformed to free pigments absorbing around 76. nm on the minutes timescale upon the induction of strong acidic pH, and subsequently there disappeared the CD signal for Qy band of B800 in the absence of B800. In addition, Carotenoids changed with the similar tendency to B850 BChl. (2) The introduction of strong basic pH gave rise to no significant changes for B800 Bchla, while B850 BChla experienced remarkable spectral blue-shift from 852 to 837 nm. Similar phe-nomenon was seen for the CD signal for Qy band of B850. Carotenoids displayed strong and pH-independent CD signals in the visible range. (3) In the case of both physiological and basic pH, broad and asymmetrical positive Tn←T1 transient absorption appeared following the pulsed photo-excitation of Car at 532 nm. By contrast, the featureless and weak positive signal was observed on the sub-microsecond timescale in the acidic pH environment. The aforementioned experimental results indicated that acidic pH-induced removal of B800 Bchla prevented the generation of the caro-tenoid triplet state (3Car*), which is known to be essential for the photo-protection function. Neverthe-less, carotenoids can still perform this important physiological role under the basic pH condition, where the spectral blue shift of B850 exerts little effect on the overall structure of the cyclic aggregate, therefore favoring the formation of carotenoid triplet state.

关键词： pH-induced B800-removal triplet state photo-protection function

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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{6.,chengdu 610054,china International Centre for Materials Physics,Chinese Academy of sciences,Shenyang 110015,china Institute of Life science and technology University of Electronic Science and Technology of China Chengdu China International Centre for Materials Physics Chinese Academy of Sciences Shenyang 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

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Adaptive detection for distributed targets in Gaussian noise with Rao and Wald tests

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science china(Information sciences) 2012年第6期55卷 1290-1300页

作者： SHUAI XiaoFei,KONG LingJiang & YANG JianYu School of electronic Engineering,university of electronic science and technology of china,{6. 610054,china School of electronic Engineering University of Electronic Science and Technology of China

The problem of adaptively detecting a range distributed target or targets in Gaussian interference is considered in this *** is assumed that a set of secondary data is ***,we derive the adaptive Rao and Wald tests with one-step detection algorithm,and find that both of them are of the same asymptotic performance as the GLRT ***,the Rao and Wald tests are derived by resorting to the two-step design *** our surprise,our derivations show that all the Rao,Wald and GLR tests in the two-step design strategy are ***,the property assessments are *** is shown that these new detectors guarantee CFAR property with respect to the Gaussian ***,simulation results show that these results are accurate.

关键词： Rao and Wald tests adaptive detection distributed targets maximum likelihood estimator

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Single-channel blind separation of overlapped multicomponents based on energy operator

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science china(Information sciences) 2010年第1期53卷 147-157页

作者： CAI QuanWei, WEI Ping & XIAO XianCi College of electronic Engineering, university of electronic science and technology of china,{6., china College of electronic Engineering University of Electronic Science and Technology of China

A method utilizing single channel recordings to blind separate the multicomponents overlapped in both time and frequency domains is proposed in this paper. The main idea of the method is based on using the energy operator and differential energy operator to estimate instantaneous frequencies and amplitudes of each component and then to reconstruct these components. This method, due to the good time resolution of the energy operator and differential energy operator, as well as the very low computational complexity, is very useful in real time processing and practical applications. Simulation results demonstrated the effciency of this method.

关键词： single channel time frequency overlap multicomponents separation energy operator differential energy operator

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