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DIRECT EXMNSIONS FOR THE DISTRIBUTION FUNCTIONS AND DENSITY FUNCTIONS OF χ~2.TYPE AND t-TYPE DISTRIBUTED RANDOM VARIABLES

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Chinese Annals of Mathematics,Series B 1996年第3期17卷 289-300页

作者： ZHENG ZUKANG(department of Statistics & Operational Research, fudan university, {2. 2.94.3,{4.) department of Statistics and Operational Research Fudan University Shanghai 299433 China

Suppose that Z1 , Z2.’’’ Zn are independent normal random variables with common meanμ and variance σ2. Then S2.and have distribution andtn-1 distribution respectively. If the normal assumption fails, there will be the remaindersof the distribution functions and density functions. This paper gives the direct expansions ofdistribution functions and density functions of S2.alld T up to o(n-1). They are more intuitiveand convenient than usual Edgeworth expansions.

关键词： Edgeworth expansion Distribution function Density function

Boundary element-free method for elastodynamics

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 641-657页

作者： CHENG Yumin1 & PENG Miaojuan2.1. shanghai Institute of Applied Mathematics and Mechanics, shanghai {2., shanghai 2.0072. china 2. department of Civil Engineering, shanghai {2., shanghai 2.0072. china 1. shanghai Institute of Applied Mathematics and Mechanics Shanghai University 200072 Shanghai China 2. department of Civil Engineering Shanghai University 200072 Shanghai China

The moving least-square approximation is discussed first. Sometimes the method can form an ill-conditioned equation system, and thus the solution cannot be obtained correctly. A Hilbert space is presented on which an orthogonal function system mixed a weight function is defined. Next the improved moving least-square approximation is discussed in detail. The improved method has higher computational efficiency and precision than the old method, and cannot form an ill-conditioned equation system. A boundary element-free method (BEFM) for elastodynamics problems is presented by combining the boundary integral equation method for elastodynamics and the improved moving least-square approximation. The boundary element-free method is a meshless method of boundary integral equation and is a direct numerical method compared with others, in which the basic unknowns are the real solutions of the nodal variables and the boundary conditions can be applied easily. The boundary element-free method has a higher computational efficiency and precision. In addition, the numerical procedure of the boundary element-free method for elastodynamics problems is presented in this paper. Finally, some numerical examples are given.

关键词： moving least-square approximation, improved moving least-square approximation, elastodynamics, boundary integral equation, meshless method, boundary element-free method, Fourier eigen transform.

BLOCKWISE PERTURBATION THEORY FOR 2.2.BLOCK MARKOV CHAINS

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Journal of Computational Mathematics 2000年第3期18卷 305-312页

作者： Jun-gong Xue Wei-guo Gao (department of Mathematics, fudan university, {2., 2.043.,{4.) 复旦大学上海 200433

Let P be a transition matrix of a Markov chain and be of the form P = qq@. The stationary distribution πT is partitioned conformally in the form (π1T, π2.). This paper establish the relative error bound in πiT (i ... 详细信息

关键词： Blockwise perturbation Markov chains stationary distribution error bound

CMC surfaces in the hyperbolic 3-space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2.and LI Zhenqi 1, 3 1. Institute of Mathematics, fudan university, shanghai 2.043.,{2. 2. department of Mathematics,Sichuan Union university, Chengdu 610064.{2. 3. department of Mathematics, Nanchang university, Nanchang 33 nstitute of Mathemalics Fudan University Shanghai China department of Mathematics Sichuan Union University Chengdu China department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1 are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

Research on nonlinear constitutive relationship of permanent deformation in asphalt pavements

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 671-682页

作者： PENG Miaojuan1 & XU Zhihong2.1. department of Civil Engineering,shanghai {2.,shanghai 2.0072.china 2. School of Transportation Engineering,Tongji {2.,shanghai 2.0092.china 1. department of Civil Engineering Shanghai University Shanghai 200072 China 2. School of Transportation Engineering Tongji University Shanghai 200092 China

To predict correctly the rut depths in asphalt pavements,a new nonlinear viscoelastic-elastoplastic constitutive model of permanent deformation in asphalt pave-ments is presented. The model combines a generalized Maxwell model with an elasto-plastic one. Then from the creep theory,the linear and nonlinear constitutive equations of the generalized Maxwell model are obtained. From the nonlinear finite element method for the rutting of the asphalt pavement,the rut depths of 4.asphalt-aggregate mixtures are obtained. And the results are compared with the ones from the finite element method by SHRP and the experiments by SWK/UN. The results in this paper are better than the ones by SHRP,and agree with the ones of the experiment by SWK/UN. This shows that the nonlinear viscoelastic-elastoplastic constitutive model,which is presented in this paper for the rutting of the asphalt pavement,is effective. The properties,such as nonlinear elastic-ity,plasticity,viscoelasticity and nonlinear viscoelasticity,which affect the rutting of an asphalt pavement,can be shown in the model. And the characteristics of the permanent deformation of the asphalt pavement can be presented entirely in the model.

关键词： asphalt pavement,permanent deformation,nonlinear viscoelastic-elastoplastic constitutive relationship,generalized Maxwell model,creep compliance.

β-delayed proton decays near the proton drip line

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2., CHEN Yongshou 2., XU Furong 3 , WANG Kun 4., PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, china 2. Nuclear Physics {4., china Institute of Atomic Energy, Beijing 102.13, china 3. {4. of Technical Physics, Peking university, Beijing 100871, china 4. shanghai Institute for Nuclear Research, shanghai 2.1800, china 1. Institute of Modern Physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear Physics department China Institute of Atomic Energy 102413 Beijing China 3. department of Technical Physics Peking University 100871 Beijing China 4. shanghai Institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2.04. namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14.nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92.h as well as the predicted “waiting point” nuclei 89Ru and 93Pd are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2. The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 14.0}o and 12.Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3) The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

FATOU　PROPERTY　ON　HARMONIC　MAPS　FROM　COMPLETE　MANIFOLDS　WITH　NONNEGATIVE　CURVATURE　AT　INFINITY　INTO　CONVEX　BALLS

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Chinese Annals of Mathematics,Series B 1995年第3期16卷 341-350页

作者： YANG YIHU(department of Mathematics,fudan {2.,shanghai {4., china.) fudan UNIV DEPT MATHSHANGHAI 200433PEOPLES R CHINA

The author considers harmonic maps on complete noncompact manifolds, solves the Dirichlet problem in manifolds with nonnegative sectional curvature out of a compact set, and proves the Fatou theorem for harmonic maps ... 详细信息

关键词： Complete manifold Harmonic map Convex ball Fatou property.

CDS Simulation and Pattern Formation of Phase Separation

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Communications in Nonlinear Science and Numerical Simulation 1998年第4期3卷 233-236页

作者： Zhanaji LIU Men CHENG Jiong RUAN and Shouji CHENG (department of Mechanics and Engineering Science, fudan university,{2.,china)(department of Mathematics, fudan university,{2., china) Dept. of Mechanics and Eng. Science Fudan University Shanghai 200433 China department of Mathematics Fudan University Shanghai 200433 China

Several properties of the generation and evolution of phase separating patterns for binary material studied by CDS model are proposed. The main conclusions are (1) for alloys spinodal decomposition, the conceptions of "macro-pattern" and "micropattern" are posed by "black-and- white graph" and "gray-scale graph" *** find that though the four forms of map f that represent the self-evolution of order parameter in a cell(lattice) are similar to each other in "macro-pattern" , there are evident differences in their micro-pattern, e.g., some different fine netted structures in the blackdomain and the white domain are found by the micro-pattern, so that distinct mechanical and physical behaviors shall be obtained. (2. If the two constitutions of block copolymers are not symmetric (i.e. r ≠ 0.5), a pattern called "grain-strip cross pattern"is discovered,in the 0.4. 4..

关键词： lattice gas automata CDS phase separation Pattern formation

Identification and Characterization of glnA Promoter and its Corresponding Trans-regulatory Protein GlnR in the Rifamycin SV Producing Actinomycete,Amycolatopsis mediterranei U32

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Acta Biochimica et Biophysica Sinica 2006年第12期38卷 831-843页

作者： Hao YU~(1&) Wen-Tao PENG~1 Yang LIU~1 Ting WU~2.Yu-Feng YAO~1 Ming-Xue CUI~1 Wei-Hong JIANG~1 Guo-Ping ZHAO~(1,3,4.) 1 Laboratory of Molecular Microbiology,Institute of Plant Physiology and Ecology,shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,shanghai 2.0032.{2. 2.department of Medicinal Chemistry,School of Pharmacy,fudan university,shanghai 2.0032.{2. 3 State Key Laboratory of Genetic Engineering & department of Microbiology,School of Life Science,fudan university,shanghai {12.,{2. 4.Laboratory of Disease and Health Genomics,Chinese National Human Genome Center at shanghai,shanghai 2.12.3,{2. Laboratory of Molecular Microbiology Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China department of Medicinal Chemistry School of Pharmacy Fudan University Shanghai 200032 China State Key Laboratory of Genetic Engineering & department of Microbiology School of Life Science Fudan University Shanghai 200433 China Laboratory of Disease and Health Genomics Chinese National Human Genome Center at Shanghai Shanghai 201203 China

The genetic requirements for the transcription of glnA,encoding the major glutaminesynthetase in a rifamycin SV-producing Amycolatopsis mediterranei strain,U32.were *** experiments showed that the promoter of U32.glnA （pglnA） was likely to have two transcriptioninitiation sites:P1and P2.located 157 and 4. nucleotides （nt） upstream of the translational start codon,*** mobility shift and DNase I footprinting analyses revealed a 30 bp cis-element locatedat 4. to 75 nt downstream of P1,or 38 to 68 nt upstream of *** sequence of the cis-element displayedhigh similarity to the corresponding regions of pglnA from Streptomyces coelicolor and *** as a reporter gene,the expression levels of U32.pglnA and its deletion derivatives under differentnitrogen-source conditions were analyzed by detecting the catechol dioxygenase activities in ***54.*** J508 and *** FS10 （glnR mutant）.These in vivo studies showed that theactivation of U32.pglnA in *** required GlnR,and its binding to the U32.pglnA was furtherconfirmed by the gel mobility shift *** and heterologous expression of the U32.glnR allowed usto detect the in vitro interaction between the U32.GlnR and the corresponding pglnA *** shown by in vivo glnR inactivation and complementation indicated that GlnR is essential for theactive transcription of glnA in U32.

关键词： glnA promoter cis-element glnR Amycolatopsis mediterranei