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LARGE DEVIATIONS FOR STATIONARY Φ-MIXING SEQUENCES IN τ-TOPOLOGY

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 149-158页

作者： Hu YIJUN department of Mathematics, wuhan university,{2. department of Mathematics Wuhan University Wuhan 430072 China

The results of Bryc on large deviations for empirical measures of stationary Φ-mixing sequences are extended. Bryc states his results in the usual weak topology on the space ofprobability measures. In this paper, under somewhat weaker assumptions than those of Bryc,the author extends Bryc's results by taking the finer topology which is generated by the integralsover bounded measurable functions.

关键词： Large deviation Empirical measure Stationary sequence Φ-mixing τ-topology

SOME BOUNDARY INCREASING PROPERTIES OF HARMONIC FUNCTIONS IN LIPSCHITZ DOMAIN

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 159-166页

作者： ZHANG YIPING department of Mathematics, wuhan university,{2.Project supported by the National Natural science Foundation of china. wuhan UNIV DEPT MATH WUHAN 430072 PEOPLES R CHINA

The object of this paper is to study the non-tangential increasing properties of positiveharmonic function u in Lipschitz domain by means of Martin representation theory. A necessaryand sufficient condition of the control of growth of u near any fixed boundary point is obtained.It is shown that the non-tangential increasing degree of u near a boundary point is exactlythe local degree of its representation measure with respect to the harmonic measure. Someexamples are given.

关键词： Martin representation Harmonic function Harmonic measure

NEW WAVELET BASES FOR NON－HOMOGENEOUS SYMBOLIC SPACE OpS1,1^m AND RELATED KERNEL－DISTRIBUTION SPACES

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Chinese Annals of Mathematics,Series B 2002年第4期23卷 551-562页

作者： YANG QIXIANGdepartment of Mathematics, wuhan university,{2. department of Mathematics Wuhan University Wuhan 430072 China

This paper constructs several classes of new wavelet bases, which are unconditional bases for related operator spaces. Using these bases, the author analyzes non-homogeneous symbolic space OpSm1,1 and two related kernel-distribution spaces, and characterizes them in two wavelet coefficients spaces. Besides, some properties for singular integral operators are studied.

关键词： Wavelet bases Symbolic spaces Kernel-distribution spaces

1.55 μm Wavelength Operation of E_r^(3+) -Doped Optical Fiber Bistability

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wuhan university Journal of Natural {2.s 1999年第4期4卷 435-438页

作者： SONG Qian 1, ZHANG Yuan cheng 2.1. College of Electronics information, wuhan university,{2.2. department of Physics, wuhan university, wuhan 430072. china wuhan university College of Electronics Information Wuhan China (GRID:grid.49470.3e) (ISNI:***) wuhan university Department of Physics Wuhan China (GRID:grid.49470.3e) (ISNI:***)

An all optical all fiber optical bistability operation has been realized in an all fiber cavity consisted with Er doped fiber and optical fiber loop mirrors. The experimental bistability threshold is consistent w... 详细信息

关键词： optical nonlinearity optical bistability Er doped fiber all fiber device

Large deviation principles for stationary NA sequences

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Chinese science Bulletin 1998年第7期43卷 536-540页

作者： HU Yijun department of Mathematics, wuhan university, {2. 430072. china department of Mathematics Wuhan University Wuhan China

Under general conditions, the large deviation principles for partial sums of stationary NA sequences are proved.

关键词： NA sequence stationary sequence partial sums large deviation principle.

SILYLATION OF CELLULOSE WITH TRICHLOROSILANE AND TRIETHOXYSILANE IN HOMOGENEOUS LiCl/N,N-DIMETHYLACETAMIDE SOLUTION

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Chinese Journal of Polymer science 2000年第2期18卷 161-168页

作者： Hai-qing Liu Li-na Zhang department of Chemistry, wuhan university, {2. 430072. china wuhan Univ Dept Chem Wuhan 430072 Peoples R China

Silyl celluloses (SiC) were prepared by reacting cellulose with chloropropyltrichlorosilane (CPTCSi) and chloropropyltriethoxysilane (CPTESi) in LiCl/N,N-dimethylacetamide (DMAc). The Si content in the silyl cellulose could be controlled by adjustment of the molar ratio of silane and cellulose. FT-IR spectra showed that cellulose was readily reacted with the above two silane reagents, and the reactivity of CPTCSi is higher than that of CPTESi. It was presumed that the reaction process belongs to graft-polymerization. The results of differential thermal analysis (DTA) indicated that the thermostability of the materials produced increased with the increase of Si content in the sample. The acid resistance of the samples SiC in 1 mol/L HCl aqueous solution was improved significantly. When Si content was ca. 2.%, the silyl cellulose has excellent thermostability, hydrophobicity, low density and stability in 1 mol/L HCl aqueous solution, owing to crosslinking of cellulose chain with silane.

关键词： sily cellulose chloropropyltrichlorosilane chloropropyltriethoxysilane LiCl/DMAc thermostability crosslinking

Hierarchical Classification of Chinese Documents Based on N grams

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wuhan university Journal of Natural {2.s 2001年第Z1期6卷 416-422页

作者： Zhou Shui geng 1, Guan Ji hong 2. He Yan xiang 2.1. State Key Laboratory of Software Engineering, wuhan university, wuhan 430072. china.2. School of Computer {2., wuhan university, wuhan 430072. china State Key Laboratory of Software Engineering Wuhan University Wuhan China School of Computer science Wuhan University Wuhan China

We explore the techniques of utilizing N gram information to categorize Chinese text documents hierarchically so that the classifier can shake off the burden of large dictionaries and complex segmentation processing, and subsequently be domain and time independent. A hierarchical Chinese text classifier is implemented. Experimental results show that hierarchically classifying Chinese text documents based N grams can achieve satisfactory performance and outperforms the other traditional Chinese text classifiers.

关键词： Chinese text classification N grams feature selection hierarchical classification

GRAPH-DIRECTED STRUCTURES OFSELF-SIMILAR SETS WITH OVERLAPSGRAPH-DIRECTED STRUCTURES OFSELF-SIMILAR SETS WITH OVERLAPSS

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Chinese Annals of Mathematics,Series B 2000年第4期21卷 403-412页

作者： HUASu RAOHUI departmentofMathematics TsinghuaUniversityBeijing100084China. departmentofMathematics WuhanUniversityWuhan430072China.

Some kinds of the self-similar sets with overlapping structures are studied by introducing the graph-directed constructions satisfying the open set condition that coincide with these sets. In this way, the dimensions ... 详细信息

关键词： Self-similar sets Graph-directed sets Overlapping Label Pisot number

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan university Journal of Natural {2.s 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. department of Chemical Engineering, wuhan university of Technology, {2. 430070, Hubei, china.2. College of Chemistry and Molecular sciences, wuhan university, {2. 430072. Hubei, china wuhan university of Technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization