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Information flow and controlling in regularization inversion of quantitative remote sensing

Science china Earth Sciences 2005年第1期48卷 74-83页

作者： YANG Hua, XU Wangli, ZHAO Hongrui, CHEN Xue & WANG Jindi Research Center for Remote Sensing and GIS, School of Geography, beijing normal university, State Key Laboratory of Remote Sensing Science, beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, china department of Mathematics, beijing normal university, beijing 100875, china 1. Research Center for Remote Sensing and GIS School of Geography Beijing Normal University State Key Laboratory of Remote Sensing Science Beijing Key Laboratory for Remote Sensing of Environment and Digital Cities 100875 Beijing China 2. department of Mathematics Beijing Normal University 100875 Beijing China

In order to minimize uncertainty of the inversed parameters to the largest extent by making full use of the limited information in remote sensing data, it is necessary to understand what the information flow in quantitative remote sensing model inversion is, thus control the information flow. Aiming at this, the paper takes the linear kernel-driven model inversion as an example. At first, the information flow in different inversion methods is calculated and analyzed, then the effect of information flow controlled by multi-stage inversion strategy is studied, finally, an information matrix based on USM is defined to control information flow in inversion. It shows that using Shannon entropy decrease of the inversed parameters can express information flow more properly. Changing the weight of a priori knowledge in inversion or fixing parameters and partitioning datasets in multi-stage inversion strategy can control information flow. In regularization inversion of remote sensing, information matrix based on USM may be a better tool for quantitatively controlling information flow.

关键词： regularization inversion, information flow, Shannon entropy decrease, information matrix.

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Redevelopment of liftoff rates of saltating sand grains based on a simple optimization model

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Science china Earth Sciences 2010年第4期53卷 568-574页

作者： CHENG Hong & ZOU XueYong State Key Laboratory of Earth Surface Processes and Resource Ecology,beijing normal university,beijing 100875,china MOE Engineering Center of Desertification and Blown-sand Control,beijing normal university,beijing 100875,china Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of china,beijing normal university,beijing 100875,china 1. State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China2. MOE Engineering Center of Desertification and Blown-sand Control Beijing Normal University Beijing 100875 China3. Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of China Beijing Normal University Beijing 100875 China

This paper is a redevelopment result of liftoff rates of saltating sand grains based on our previous *** sand flow is a complex multi-phase flow because of a special two-phase gas-solid flow near ground *** extensive research on the movement of blowing sand,no model fully characterizes aeolian sand flow,and large differences often exist between simulations of aeolian sand movement and field *** key problem is a few of sufficient research on liftoff rates of saltating sand grains(also called the number of liftoff sand grains per unit time and per unit bed area).It is necessary to re-search in advance liftoff rates of saltating sand *** redeveloped liftoff rates of saltating sand grains by establishing an optimization model based on the flux of aeolian sand flow at different heights of the sampler in wind tunnel and the simulated capture of saltating sand grains by different heights of the sampler that are from different liftoff position(distance from the sampler) in order to revise previous inversion condition of liftoff rates of saltating sand *** rates increased rapidly with increasing wind *** frictional wind velocities of u=0.67,0.77,0.82,0.83,and 0.87 m s-1,liftoff rates were 3840,954502,5235114,5499407,and 7696291 sand grain s-1 m-2,*** rates could be expressed as the square of the instantaneous frictional wind velocity and a constant(0.663) that differs from the critical(threshold) frictional wind velocity at which saltation *** our results require additional experimental validation and the simple optimization model must be improved,they nonetheless provide a strong basis for future research.

关键词： liftoff rates of saltating sand grains optimization model wind tunnel two-phase gas-solid flow

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A Remark on Multilinear Oscillatory Singular Integrals

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Acta Mathematica Sinica,English Series 2000年第4期16卷 655-668页

作者： Shanzhen Lu Dunyan Yan department of Mathematics, beijing normal university, beijing 100875. P. R. china department of Mathematics Beijing Normal University Beijing 100875 P. R. China

In this paper we study multilinear oscillatory singular integrals with rough kernel and give a criterion of certain boundedness for this kind of operator

关键词： Multilinear oscillatory integrals Calderon-Zygmund kernel BLO space

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Conformational Analysis of γ-Butyrolactones by Nuclear Magnetic Resonance Spectroscopy

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Chinese Chemical Letters 1997年第10期8卷 885-888页

作者： Fu An KANG and Cheng Lie YIN (department of Chemistry beijing normal university , beijing 100875) beijing normal UNIV DEPT CHEMBEIJING 100875PEOPLES R CHINA

A series of trans-4, 5-disubstituted -γ-butyrolactones are found to assume two different envelope conformations by means of nuclear magnetic resonance spectroscopy.

关键词： Conformational Analysis of Butyrolactones by Nuclear Magnetic Resonance Spectroscopy

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The studies on neurogenesis induced by brain injury inadult ring dove

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Cell Research 1998年第2期8卷 151-158页

作者： ZUO MING XUE(Biology department, beijing normal university, beijing100875, china) Biology department Beijing Normal University Beijing 100875 ChinaReceived 11February1998 Revised 16March1998 Accepted 25March1998

It was the first time demonstrated by us that the number of newborn neurons was increajsed after making lesion in forebraill of adult ring dove (Streptopelia risoria)by means of autoradiography and *** in the adult avian is restricted to the telencephalon. In doves with bilateral electrolytic lesion of nucleus ectostriatum (E), the mean number of proliferating cells in the lateral ventricular zone (LVZ) and newborn neurons in the forebrain increased by 1.95 times and 2.38times respectively as compared with that in intact doves. The most relllarkable increase of neurogenesis induced by nucleus ectostriatum lesions was found at the anteriorposterior level 3 (L3), where the lesion site was *** results showed that the electrolytic brain lesion altered the distribution pattern of proliferating cells in theLVZ and resulted in increase of the number of newborn neurons in the non-VZ areas of forebrain. The changes in number and distribution pattern of proliferating cells in LVZ and newborn neurons in forebrain may be dependent on site of lesion. Studies on the relationship between proliferating cells in LVZ and newly generated neurons in non-VZ areas may help to understand the mechanism of brain plasticity and development.

关键词： Autoradiography neurogenesis brain lesion ring dove

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On the weak convergence of super-Brownian motion with immigration

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Science china Mathematics 2009年第9期52卷 1875-1886页

作者： ZHANG Mei School of Mathematical Sciences, beijing normal university, beijing 100875, china School of Mathematical Sciences Beijing Normal University Beijing 100875 China

We prove fluctuation limit theorems for the occupation times of super-Brownian motion with immigration. The weak convergence of the processes is established, which improves the results in references. The limiting proc... 详细信息

关键词： super-Brownian motion with immigration occupation time process central limit theorem tightness 60J80 60F05

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Environmental　risk　assessment　of　the　middle　route　of　south－to－north　water　transferring　source　project　in　china

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Journal of Environmental Sciences 1996年第3期8卷 285-291页

作者： Wang Huadong Wang Fei(Institute of Environmental Sciences,beijing normal university, beijing 100875, china) Institute of Environmental Sciences Beijing Normal University Beijing 100875 China

This paper focused on the environment risk of the middle route of south-to-north water transferring source project in china. Analytic hierarchy process was applied to risk identification,fuzzy probability-fault tree analysis to risk probability assessment,statistics and analogy process to risk consequences assessment, lastly, grey relevant analysis and comprehensive index process to risk impact evaluation. The main environment risk accident of the project is dam failure, the main causative factors of the accident are catastrophic flood and wrecking earthquake. The flash flood, due to dam failure, will impact on nature, society and economy. The major environment risk areas are Jingzhou and Xiangfan,Hubei Province. The environment risk management measures should be adopted in order to ensure the safety of the project-environment complex system.

关键词： water source project environment risk risk assessment

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Relativist ic Corrections to the Thermal Sunyaev-Zel'dovich Power Spectrum

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Chinese Journal of astronomy and Astrophysics 2003年第5期3卷 410-414页

作者： Hai-Ning LiNational Astronomical Observatories, Chinese Academy of Sciences, beijing 100012 lhndepartment of astronomy, beijing normal university, beijing 100875 National Astronomical Observatories CAS NAOC Beijing 100012 China []Department of Astronomy Beijing Normal University Beijing 100875

We present a quantitative estimate of the relativistic corrections to thethermal SZ power spectrum produced by the energetic electrons in massive clusters. The correctionsare well within 10% for current experiments with working frequencies below ν 350 GHz. Moreover, the corrections appear to be slightlysmaller at higher l or smaller angular scales. We conclude that there is no need to include therelativistic corrections in the theoretical study of the SZ power spectrum especially at lowfrequencies unless the SZ power spectrum is used for precision cosmology.

关键词： cosmic microwave background cosmology: theory galaxies: clusters: general

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ALMOST　PERIODIC　SOLUTIONS　OF　NEUTRAL　FUNCTIONAL　DIFFERENTIAL　EQUATIONS　WITH　NONAUTONOMOUS　OPERATOR

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Chinese Annals of Mathematics,Series B 1995年第4期16卷 519-530页

作者： YUAN RONG(department of Mathematics, beijing normal universityl beijing 100875, china.) beijing normal UNIV DEPT MATHBEIJING 100875PEOPLES R CHINA

This paper presents some existence theorems on almost periodic solutions for almost periodicneutral functional differential equation and its perturbed systems by means of Liapunov functional, and extends the correspon... 详细信息

关键词： Almost periodic solution Neutral functional differelltial equation Nonautollomous operator

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Entropy number and non-linear approximations on multivariate Besov space by manifolds of finite pseudo-dimension

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Progress in Natural Science:Materials International 2006年第3期16卷 260-265页

作者： LONG Jingfan and FANG Gensun (School of Mathematical Sciences, beijing normal university, beijing 100875, china department of Computer Science, Information Technology Institute, beijing 100101, china) [a]School of Mathematical Sciences Beijing Normal University Beijing China [b]department of Computer Science Information Technology Institute Beijing China

We determine the asymptotic order of entropy number and optimal non -linear approximations of anisotropic periodic Besov class of Bpθr(Td') (1≤p≤∞,1≤0≤∞) by manifolds of finite pseudo-dimension in the metric Lq... 详细信息

关键词： Pseudo-dimension anisotropic Besov class of functions entropy number nonlinear width.

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