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An asymptotic result of super-Brownian motion on hyperbolic space

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Chinese Science Bulletin 1997年第15期42卷 1240-1244页

作者： TANG JiashanDepartment of Mathematics, beijing Normal University, beijing 100875. china Institute of Mathematics, Shantou University, Shantou 515063, china Department of Mathematics Beijing Normal University Beijing China Institute of Mathematics Shantou University Shantou China

SUPERPROCESS is one kind of measure-valued branching Markov processes. In the recentdecades many results of superprocesses on Euclidean spaces and on general abstract spaces havebeen obtained, but there is only little work on Riemannian manifold. In this note, wewill consider the super-Brownian motions on the hyperbolic space of dimension d and give anasymptotic result of this process (see Corollary 1 below). Iscoe investigated a similar prob-

关键词： hyperbolic space radial super-Brownian motion hitting probability asymptotic.

Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2,3, WANG Pengxin4, YANG Hua1,2,3, LIU Shaomin1,2,3 & WANG Jindi1,2,3 1. Research center for Remote Sensing and GIS, School of Geography, beijing Normal University, beijing 100875. china 2. State Key Laboratory of Remote Sensing Science, beijing 100875. china 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875. china 4. Department of Information Management, College of Information and Electronic Engineering, china Agricultural University, beijing 100083, china 1. Research center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing 100875 China 2. State Key Laboratory of Remote Sensing Science Beijing 100875 China 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing 100875 China 4. Department of Information Management College of Information and Electronic Engineering China Agricultural University Beijing 100083 China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

Extracting impervious surfaces from multi-source satellite imagery based on unified conceptual model by decision tree algorithm

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Science china(Technological Sciences) 2010年第S1期53卷 68-74页

作者： QIAO Yu,LIU HuiPing,BAI Mu,WANG XiaoDong & ZHOU XiaoLuo School of Geography,beijing Normal University,beijing 100875.china 1. School of Geography Beijing Normal University Beijing 100875 China

Extraction of impervious surfaces is one of the necessary processes in urban change *** paper derived a unified conceptual model (UCM) from the vegetation-impervious surface-soil (VIS) model to make the extraction more effective and *** uses the decision tree algorithm with indices of spectrum and texture,*** this model,we found both dependent and independent indices for multi-source satellite imagery according to their similarity and *** purpose of the indices is to remove the other land-use and land-cover types (e.g.,vegetation and soil) from the imagery,and delineate the impervious surfaces as the *** has the same steps conducted by decision tree *** Landsat-5 TM image (30 m) and the Satellite Probatoire d’Observation de la Terre (SPOT-4) image (20 m) from Chaoyang District (beijing) in 2007 were used in this *** results show that the overall accuracy in Landsat-5 TM image is 88%,while 86.75% in SPOT-4 *** is an appropriate method to meet the demand of urban change detection.

关键词： multi-source satellite imagery impervious surfaces extraction VIS model decision tree algorithm

A New Almost Periodic Type Solution of First Order Neutral Delay Differential Equations with Piecewise Constant Argument

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Acta Mathematica Sinica,English Series 2001年第3期17卷 403-412页

作者： Rong YUAN Department of Mathematics,beijing Normal University,beijing 100875.P.R.china E-mail:ryuan@*** Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

In this paper,we introduce a new class of ergodic sequences,pseudo almost periodic sequences,and study the existence of pseudo almost periodic sequences to difference *** the basis of these,we investigate the existence of pseudo almost periodic solutions for neutral delay differential equations with piecewise constant argument, d/(dt)(y(t)+py(t-1))=qy(2[(t+1)/2])+g(t,y(t),([t])).

关键词： Pseudo almost periodic solutions Pseudo almost periodic sequences Neutral delay equation Piecewise constant argument

Problems in wavelet analysis of hydrologic series and some suggestions on improvement

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Progress in Natural Science:Materials International 2007年第1期17卷 80-86页

作者： WANG Hongrui, YE Letian, LIU Changming, YANG Chi and LIU Peng ( College of Water Sciences, beijing Normal University, beijing 100875. china Key Laboratory for Water and Sediment Sciences, Ministry of Education, beijing 100875. china School of Mathematical Sciences, Peking University, beijing 100089, china College of Engineering Sciences, University of Region, Canada) [a]College of Water Sciences Beijing Normal University Beijing China [b]Key Laboratory for Water and Sediment Sciences Ministry of Education Beijing China [c]School of Mathematical Sciences Peking University Beijing China [d]College of Engineering Sciences University of Region Canada

Applying the wavelet theory and methods to investigate the hydrologic processes such as precipitation and runoff is a hot field. However, several aspects in research are usually ignored: the effect of admissible condition of wavelet functions and the disturbance of noises for the detection of periods, the effect of the length of a hydrologic time-series on the final result, and the choice between the anomaly and the original time series for wavelet analysis. In this paper, these issues are fully discussed. Precipitation data from Lanzhou Precipitation Station are taken for case study. The result indicates that in the wavelet analysis of hydrologic series, denoise methods should be used to eliminate the influence of noises. The MexHat wavelet function satisfies the admissible condition, which ensures that the periodic properties of hydrologic processes can be well represented by using the MexHat wavelet for decomposition. The affected range of hydro-logic series which should be discarded before analysis is given. It is also suggested that the anomaly series should be used to highlight the actual undulation of the hydrologic series.

关键词： wavelet analysis hydrologic process admissible condition noise period.

Moderate deviation for super-Brownian motion with immigration

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Science china Mathematics 2004年第3期47卷 440-452页

作者： ZHANG Mei Department of Mathematics, beijing Normal University, beijing 100875. china Department of Mathematics, The Central University of Finance and Economics, beijing 100081, china 1. Department of Mathematics Beijing Normal University 100875 Beijing China 2. Department of Mathematics The Central University of Finance and Economics 100081 Beijing China

We prove a moderate deviation principle for a super-Brownian motion with immigration of all dimensions, and consequently fill the gap between the central limit theorem and large deviation principle.

关键词： moderate deviation principle super-Brownian motion with immigration large deviation principle evolution equation

Compactness of the commutators of parabolic singular integrals

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Science china Mathematics 2010年第10期53卷 2633-2648页

作者： CHEN YanPing1 & DING Yong2,3 1Department of Mathematics and Mechanics,University of Science and Technology beijing,beijing 100083,china 2School of Mathematical Science,beijing Normal University,beijing 100875.china 3Laboratory of Mathematics and Complex Systems (BNU),Ministry of Education of china,beijing 100875.china 1. Department of Mathematics and Mechanics University of Science and Technology Beijing Beijing 100083 China2. School of Mathematical Science Beijing Normal University Beijing 100875 China3. Laboratory of Mathematics and Complex Systems (BNU) Ministry of Education of China Beijing 100875 China

In this paper,the authors prove that the commutator [b,T] of the parabolic singular integrals is a compact operator on Lp(Rn)(1 < p < ∞) if and only if b ∈ VMO(Rn,ρ).The result is substantial improvement and extens... 详细信息

关键词： parabolic singular integrals commutators compactness BMO VMO

Effects of CDK4 antisense RNA on Human breast cancer cell proliferation and expression of cyclinD1,cyclinE and CDK2

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Chinese Science Bulletin 1999年第6期44卷 541-544页

作者： SANG Jianli WANG YongchaoLaboratory of Cell Biology, Department of Biology, beijing Normal University, beijing 100875. china Laboratory of Cell Biology Department of Biology Beijing Normal University Beijing China

The role of CDK4 in human breast cancer cell proliferation and expression of cyclinD1, cyclinE and CDK2 has been investigated using inhibition of CDK4 expression by antisense RNA. When CDK4 expression was inhibited, the rate of cell proliferation and tumorigenecity decreased *** indicates that CDK4 plays an important role in formation and development of breast tumor. The resuits of Northern blot analysis showed that the levels of cyclinD1 and CDK2 mRNAs changed slightly whereas the level of cyclinE mRNA decreased obviously. It is suggested that the expression of CDK4 is necessary for induction of cyclinE expression. Thus, inhibition of CDK4 expression affects not only the role of CDK4 itself but also the role of other genes.

关键词： CDK4 breast cancer cell antisense RNA cyclinE.

Reading comprehension without phonological mediation:Further evidence from a Chinese aphasic individual

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Science china(Life Sciences) 2009年第5期52卷 492-499页

作者： HAN ZaiZhu & Bi YanChao State Key Laboratory of Cognitive Neuroscience and Learning, beijing Normal University, beijing 100875. china State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China

An important issue in visual word comprehension literature is whether or not semantic access is mediated by phonological processing. In this paper, we present a Chinese individual, YGA, who provides converging evidence to directly address this issue. YGA has sustained damage to the left posterior superior and middle temporal lobe, and shows difficulty in orally name pictures and reading printed words aloud. He makes phonological errors on these tasks and also semantic errors on picture naming, indicating a deficit at accessing the phonological representations for output. However, he is intact at understanding the meaning of visually presented words. Such a profile challenges the hypothesis that semantic access in reading is phonologically mediated and provides further evidence for the universal principle of direct semantic access in reading.

关键词： word reading phonological mediation Chinese case study