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ON HASEMAN BOUNDARY VALUE PROBLEM FOR A CLASS OF META-ANALYTIC FUNCTIONS

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Acta Mathematica Scientia 2011年第1期31卷 39-48页

作者：汪玉峰杜金元 School of Mathematics and Statistics Wuhan University

In this article, Haseman boundary value problem for a class of meta-analytic functions is studied. The expression of solution and the condition of solvability for Haseman boundary value problem are obtained by changing the problem discussed into the equivalent Haseman boundary value problem of bi-analytic function. And the expression of solution and the condition of solvability depend on the canonical matrix.

关键词： Meta-analytic function bi-analytic function Haseman boundary value prob- lem canonical matrix

EVALUATION　OF　HFAM　ON　A　FLOW　OVER　A　BACKWARD－FACING　STEP

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Journal of Hydrodynamics 1996年第3期8卷 25-30页

作者： Zhang Xiao-yuan Li Wei (department of River Engineering, wuhan university of Hydraulic & Electric Power Engineering, wuhan, 430072., P. R. china) wuhan Univ of Hydraulic & Electric Power Engineering Wuhan China

A numerical solution for steady incompressible fluid flow over a two-dimensional backward-facing step for laminar condition was developed using a Hybrid Finite Analysis Method (HFAM). Attention is focused on obtaining accurate solution. The result of HFAM on the above problem is compared with other numerical solutions and experimental data to evaluate its numerical accuracy. It is concluded that some of the serious discrepancies that have occurred between prediction and observation at a large Reynolds number condition, and attributed in earlier studies to the inadequacy of two-dimensional model, had been due to the inaccuracy of the solution.

关键词： hybrid finite analysis method Navier-stokes laminar flow backwardfacing step.

THE UNITED METHOD FOR THE CALCULATION OF SEEPAGE CONTROL BY ADOPTING WEIGHTING SOIL LAYER ON THE BACK SIDE OF DIKE

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Journal of Hydrodynamics 2001年第4期13卷 92-97页

作者： Liu Chuan-shun, Yang Jin-zhong College of Water Conservancy and Hydropower Engineering, wuhan university, wuhan 430072. china wuhan Univ. Wuhan 430072 China

Constructing a weighting soil layer at the downstream toe of dike on layered ground is an effective measure to prevent the foundation from blowout failures. In this paper, a series of differential equations describing the seepage flow in layered dike foundation were established, and a united method combining analytic method with one-dimensional finite difference method was proposed for solving the equations. The case study shows that the results calculated by the united method are considerably identical to the computational results of Finite Element Method (FEM), and the united method is very simple and easy compared to the FEM.

关键词： dike weighting soil layer seepage calculation seepage control united method

H-VERSION ADAPTIVE FINITE ELEMENT METHOD FOR THREE-DIMENSIONAL SEEPAGE PROBLEM

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Journal of Hydrodynamics 2003年第3期15卷 122-126页

作者： Feng Xue-min, Chen Sheng-hong School of water Resource and hydropower, wuhan university, wuhan 430072. china SchoolofwaterResourceandhydropower WuhanUniversityWuhan430072China

The h-version adaptive finite element method for 3-D seepage problem ispresented in this paper. The adaptive system includes 4 modules; 3-D mesh generation, finite elementanalysis for 3-D seepage, mesh error estimatio... 详细信息

关键词： three-dimension seepage adaptive system finite element method (FEM) tetrahedron element

Some Boundary Fractal Properties of the Convolution Transform of Measures by an Approximate Identity

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Acta Mathematica Sinica,English Series 1999年第2期15卷 207-214页

作者： Zhiying Wen, department of Mathematics, wuhan university, wuhan 430072. P. R. china department of Applied Mathematics, Tsinghua university, Beijing 100084, P. R. chinaE-mail: wenzy@tsinghua.edu.cnYiping Zhang, department of Mathematics, wuhan university, wuhan 430072. P. R. chinaE-mail: ypzhang@*** department of Mathematics Wuhan University Wuhan P. R. China department of Applied Mathematics Tsinghua University Beijing P. R. China

We consider the convolution transforms of measures on Rd defined by some approximate identity. We shall establish some relations between the irregular boundary properties of the convolution function and the local Lipschitz exponent of the measure. In particular, the results can be applied to the Poisson and Gauss-Weierstrass kernels. We can then obtain some singular boundary behavior of positive harmonic or parabolic functions on R+d+1 by multifractal analysis of measures.

关键词： Approximate identity Multifractal Logarithmic density

Edge Crossing Minimization Algorithm for Hierarchical Graphs Based on Genetic Algorithms

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wuhan university Journal of Natural Sciences 2001年第Z1期6卷 555-559页

作者： Shen Wei xiang, Huang Jing wei College of Computer, wuhan university, wuhan 430072. china College of Computer Wuhan University Wuhan 430072 China

We present an edge crossing minimization algorithm for hierarchical graphs based on genetic algorithms, and comparing it with some heuristic algorithms. The proposed algorithm is more efficient and has the following advantages: the frame of the algorithms is unified, the method is simple, and its implementation and revision are easy.

关键词： hierarchical graph edge crossing genetic algorithms

Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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wuhan university Journal of Natural Sciences 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, wuhan 430070, Hubei, china 2. College of Chemistry and Molecular Sciences, wuhan university, wuhan 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

Synthesis of Schiff Base Type Macrocycles Containing Naphthalene Ring

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Chinese Chemical Letters 1997年第7期8卷 569-572页

作者： Chang Rong NIU Hai Ning ZHANG Cheng Tai WU(department of Chemistry, wuhan university, wuhan 430072. wuhan UNIV DEPT CHEMWUHAN 430072PEOPLES R CHINA

A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy) ethane and four appropriate diamines. The chemical structures of the new compounds were characterized by elemental analysis, infrared spectra, nuclear magnetic resonance spectra and mass spectrometry.

关键词： OCH IR cm KBr HNMR Synthesis of Schiff Base Type Macrocycles Containing Naphthalene Ring

Defect Properties of GaAs by Positron Annihilation

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wuhan university Journal of Natural Sciences 1996年第1期1卷 45-48页

作者： Chen Zhiquan Ma Li Li Shiqing Yan Hepin Wang Shaojie (department of physics, wuhan university,wuhan 430072.china) department of physics Wuhan University Wuhan China

Positron lifetime and Doppler Broadening spectra have been measured for three types of GaAs semiconductors. Direct evidence of native vacancy-type defects is found in the semi--insulating (SI-type) and n-type sample as its average lifetime Tin and S-parameter are larger than the bulk value. No positron trapping occurred in p-type GaAs. The lifetime spectrum of n-GaAs has also been measured as a function of temperature. The increase in average lifetime τm from 226 ps to 234 ps at the temperature range 95-330 K was observed and was explained by the ionization of the vacancy. The slight increase in bulk lifetime τb with the temperature was caused by the latticeexpansion and expansion coefficient α=14×10-6-1 was evaluated.

关键词： positron annihilation semiconductors,defect