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Perturbations of the radical of nest algebras

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Chinese Science Bulletin 1998年第7期43卷 556-560页

作者： LU Fangyan 1.and LU Shijie 2.1. {1. of Mathematics, Suzhou university, Suzhou 2.5006,{2. 2. {1. of Mathematics, Zhejiang university, Hangzhou 31.02.,{2. department of Mathematics Suzhou University Suzhou China department of Mathematics Zhejiang University Hangzhou China

Let R N and K-N be the radical ideal and the compact operator ideal of nest algebra T(N) respectively. It is proved thatR-N+K-N=span{T∈T(N)∶TT(N)NCT}=span{T∈T(N): #σ′(ST)≤1. S∈T(N)}.

关键词： nest algebras radical perturbation.

Uniform estimate for maximum of randomly weighted sums with applications to insurance risk theory

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Science china Mathematics 2005年第10期48卷 1379-1394页

作者： WANG Dingcheng~1.SU Chun~2.& ZENG Yong~1.1. School of Management and School of Applied Mathematics,{1. of Electronic Science and Technology of china,{2. 61.054,china 2. department of Statistics and Finance,{1. of Science and Technology of china,Hefei 2.002.,china 1. School of Management and School of Applied Mathematics University of Electronic Science and Technology of China 610054 Chengdu China 2. {1. of Statistics and Finance University of Science and Technology of China 230026 Hefei China

This paper obtains the uniform estimate for maximum of sums of independent and heavy-tailed random variables with nonnegative random weights, which can be arbitrarily dependent of each other. Then the applications to ... 详细信息

关键词： dependent stochastic return, discount factor, heavy-tails, discrete time insurance risk model, maxima of randomly weighted sums, ruin probability, tail probabilities, uniformly asymptotic estimate.

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1.2. SUN Weiguo1. HOU Shilin3 & FENG Hao4 1. Institute of Physics, College of Chemical Engineering,{1., chengdu 61.065,{2. 2. Institute of Theoretical Physics, Xihua Normal university, Nanchong 637002.{2. 3. department of Physics,{2. Oceanography university, Qingdao 2.6003,{2. 4. College of Physics,{1., chengdu 61.065,{2. 1. Institute of Physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical Physics Xihua Normal University 637002 Nanchong China 3. department of Physics China Oceanography University 266003 Qingdao China 4. College of Physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Automorphisms with order three of affine Lie algebras

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Chinese Science Bulletin 1998年第21期43卷 1793-1798页

作者： JIN Quanqin 1.2.and HOU Zixin 2.1. department of Mathematics, Hebei university, Baoding 071.02.{2. 2. department of Mathematics, Nankai university, Tianjin 300071.{2. department of Mathematics Hebei University Baoding China department of Mathematics Nankai University Tianjin China

Some properties of automorphisms of affine Lie algebras are presented. Automorphisms with order three are classified up to conjugacy, and their fixed point sets are also computed. As a corollary, it is proved that two... 详细信息

关键词： affine Lie algebra automorphism of order three first (second) kind of automorphism.

Shape blending of artistic brushstroke represented by disk B-spline curves

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Progress in Natural Science:Materials International 2007年第12期17卷 1501-1507页

作者： Cheng Min1.2.and Wang Guojin1.1. {1. of Mathematics, Zhejiang university, Hangzhou 31.02.,{2. 2. {1. of Mathematics, Zhejiang university of Technology, Hangzhou 31.032.{2.) department of Mathematics Zhejiang University Hangzhou 310027 China 2. {1. of Mathematics Zhejiang University of Technology Hangzhou 310032 China

This paper presents an algorithm for automatically generating in-between frames of two artistic brushstrokes. The basic idea of the algorithm is to represent the two key frames of artistic brushstrokes in disk B-spline curves, and then make blending of their geometric intrinsic variables. Given two key frames of artistic brushstrokes, the skeleton curves can be obtained by certain skeleton-based techniques. After disk B-spline representation of the key frames is generated, interpolation of the intrinsic variables of the initial and the target disk B-spline curves is carried out. Examples show that this method can efficiently create in-between frames of artistic brushstrokes.

关键词： computer aided calligraphy shape blending brushstroke disk B-spline curve skeleton.

Density-functional formula for strongly correlated systems

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Progress in Natural Science:Materials International 2005年第5期15卷 395-401页

作者： WANG Huaiyu1.*, HAN Rushan2.and CHEN Nanxian1.1. {1. of Physics, Tsinghua university, Beijing 1.0084,{2. 2. {1. of Physics, Peking university, Beijing 1.0871.{2.) department of Physics Tsinghua University Beijing 100084 China department of Physics Peking University Beijing 100871 China

Density functional method is applied for strongly correlated systems. Based on the assumption that the systems are composed of electrons in singly-occupied orbitals and those in doubly-occupied orbitals, a set of self-consistent equations are obtained by standard variation procedure. The equations consist of two parts. One part is to solve the wave functions of the electrons in singly-occupied orbitals and the other is to solve the wave functions of the electrons in doubly-occupied orbitals. The physical meanings of the terms appearing in the equations are discussed.

关键词： density-functional theory strongly correlated systems doubly-occupied orbital two-particle wave function self-consistent equations.

Evaluation of Sustainable Land Management and Diagnosis of Obstacle at County Scale in sichuan Basin:Taking Lezhi County as Example

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1. 2. 3 , LIU Qing 1. 1. {1. Institute of Biology, Chinese Academy of Sciences, {1. 61.041. {2.,china 2. Graduate university of Chinese Academy of Sciences, Beijing 1.0049, china 3. Academy of Land Reconnaissance and Layout of {2. Province , {1. 61.031. {2., china chengdu Institute of Biology Chinese Academy of Sciences Chengdu Sichuan China Graduate university of Chinese Academy of Sciences Beijing China Academy of Land Reconnaissance and Layout of sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in sichuan Basin, Southwest of{1., and evaluated the case of sustainable land management of Lezhi County from 1.90 to 2.01. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 1. indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1.90 and 2.01. The value of obstacles degree of five indicators exceeded 5 in 1.90, but in 2.01. only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

Effect of an impurity on 3-electron quantum dots in magnetic fields

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 521-530页

作者： LIU Yimin1.2. HUANG Gangming1.& BAO Chengguang1.1. {1. of Physics, Zhongshan university, Guangzhou 51.2.5,{2. 2. {1. of Physics, Shaoguan university, Shaoguan 51.0}05,{2. 1. department of Physics Zhongshan University 510275 Guangzhou China 2. {1. of Physics Shaoguan University 512005 Shaoguan China

The ground-state property of a 2.dimensional 3-electron quantum dot (QD) subjected to an external magnetic fieldB and affected by an impurity is studied. The impurity is located at thez-axis by a distanced from the plane of the dot. The evolution of the angular momentumL o and the spinS o of the ground state in accordance withB andd has been calculated, and the results are summarized and plotted in a (L o,S o) diagram. The spatial distribution of the electrons (the size and the geometric features) and the optical absorption have also been investigated. The (L o S o) diagram indicates thatL o andS o may jump whend and/orB vary. It was found that, due to the constraints arising from symmetry, each symmetric geometry is accessible only to a specific group of states having specificL o andS o.

关键词： quantum dot, ground state, charged impurity, magnetic field.

Theoretical study of aging effects on LaNi_(5) tritium storage

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 676-686页

作者： PING Feilin1.2. JIANG Gang1. ZHANG Lin2.& ZHU Zhenghe1.1. Institute of Atomic and Molecular Physics, sichuan university, chengdu 61.065,{2. 2. Research Center of Laser Fusion, Mianyang 62.900,{2. 1. Institute of Atomic and Molecular Physics Sichuan University 610065 Chengdu China 2. Research Center of Laser Fusion 621900 Miangyang China

The electronic structure and energy of La2.i1.H1.0}and La2.i1.H1.He (He is at tetrahedral, octahedral or twelve-face polyhedral interstitials) double cells have been calculated using the density functional theory. Their equilibrium structure, energy bands, electronic density of states (DOS) and X-ray diffraction are presented and discussed. The results indicate the helium-3 produced due to the decay of tritium is most possibly sited at twelve-face polyhedral and octahedral interstices and changes the thermodynamic properties of LaNi5 tritide system. The changes due to aging such as the reduction in the isotherm plateau pressure, increase of the isotherm plateau slope, and appearance of deeply trapped hydrogen are caused not only by the lattice expansion, but also by modification of the electronic structure due to the presence of He.

关键词： LaNi5 alloy, density functional theory, electronic structure, aging.