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The Hausdorff Dimension of Sections

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Chinese Annals of mathematics,Series B 2007年第2期28卷 187-194页

作者： Min NIU Lifeng XI department of mathematics and Mechanics Beijing University of Science and Technology Beijing 100083China institute of mathematics Zhejimag Wanli University Ningbo 315100 Zhejiang China

The notion of finite-type open set condition is defined to calculate the Hausdorff dimensions of the sections of some self-similar sets, such as the dimension of intersection of the Koch curve and the line x=α with ... 详细信息

关键词： Hausdorff dimension Self-similar set Section Open set condition

Difference discrete connection and curvature on cubic lattice

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Science China mathematics 2006年第11期49卷 1458-1476页

作者： WU Ke, ZHAO Weizhong & GUO Hanying department of mathematics, Capital Normal University, beijing 10003., China institute of Theoretical Physics, Chinese Academy of Sciences, beijing 100080, China 1. department of mathematics Capital Normal University Beijing 100037 China 2. institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

In a way similar to the continuous case formally, we define in different but equivalent manners the difference discrete connection and curvature on discrete vector bundle over the regular lattice as base space. We deal with the difference operators as the discrete counterparts of the derivatives based upon the differential calculus on the lattice. One of the definitions can be extended to the case over the random lattice. We also discuss the relation between our approach and the lattice gauge theory and apply to the discrete integrable systems.

关键词： discrete connection, discrete curvature, noncommutative calculus, lattice gauge theory, discrete Lax pair.

Bers-Orlicz Spaces on the Product Riemann Surface

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Acta Mathematica Sinica,English Series 1994年第3期10卷 249-259页

作者： Ma Jigang department of Applied mathematics Chengdu University of Science and technology Chengdu,610065 China He Yuzan {3. of mathematics Academia Sinica beijing,100080 China 1. department of Applied mathematics Chengdu University of Science and Technology 610065 Chengdu China 2. institute of mathematics Academia Sinica 100080 Beijing China

In this paper,the Bers-Orlicz spaces on the automorphic form A_α■(G)(or EA_α■(G)) and L_α■(G)(E_α■(G))on the product Riemann surfaces are *** prove that each f ∈A_α■(G) is a cusp *** f ∈A_α■(G),we give the reproducing ***,we give the projective operator P_αfrom L_α■(G) to A_α■(G)(or E_α■(G) to EA_α■(G)).After giving some fundamental properties of the Poincaréseries,we prove a dual theorem A_α■(G)=(EA_α■(G))~*.

关键词： Bers-Orlicz Spaces on the Product Riemann Surface

Generalized Self-Adaptive Genetic Algorithms

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 72-75页

作者： Bin Wu Xuyan Tu Jian Wu Information Engineering School, University of Science and technology beijing, beijing 100083. China {3. of Information and Control Engineering, Southwest institute of technology, Mianyang 621002, China Information Engineering School University of Science and Technology Beijing Beijing 100083 China department of Information and Control Engineering Southwest Institute of Technology Mianyang 621002 China

In order to solve the problem between searching performance and convergence of genetic algorithms, a fast genetic algorithm generalized self-adaptive genetic algorithm (GSAGA) is presented. (1) Evenly distributed initial population is generated. (2) Superior individuals are not broken because of crossover and mutation operation for they are sent to subgeneration directly. (3. High quality im- migrants are introduced according to the condition of the population schema. (4) Crossover and mutation are operated on self-adaptation. Therefore, GSAGA solves the coordination problem between convergence and searching performance. In GSAGA, the searching per- formance and global convergence are greatly improved compared with many existing genetic algorithms. Through simulation, the val- idity of this modified genetic algorithm is proved.

关键词： generalized self-adaptive genetic algorithm initial population immigration fitness function

Two possible mechanisms for vortex self-organization

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Science China Earth Sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1 & GAO Shouting3.1. Chinese Academy of Meteorological Sciences, beijing 100081, China 2. department of Space Information Science, Nanjing University of Information Science and technology, Nanjing 210044, China 3. {3. of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, China 2. department of Environmental Science Nanjing University of Information Science and Technology Nanjing 210044 China 1. Chinese Academy of Meteorological Sciences Beijing 100081 China 3. institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

Lie symmetry and conservation law of Birkhoffian system

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Chinese Science Bulletin 1999年第4期44卷 318-320页

作者： MEI Fengxiangdepartment of Applied Mechanics , beijing institute of technology, beijing 100081, China department of Applied Mechanics Beijing Institute of Technology Beijing China

The Lie symmetry of Birkhoffian system was studied, the condition under which the system admits the one-parameter Lie group of transformation with infinitesimal generator was given, and the structural equation and the... 详细信息

关键词： symmetry conservation law Birknoffian system.

On three-dimensional geological modeling and visualization

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Science China Earth Sciences 2004年第8期47卷 739-748页

作者： WU Qiang1 & XU Hua2 1. department of Resource Exploitation Engineering, China University of Mining and technology, beijing 100083. China 2. beijing institute of Petrochemical technology, beijing 102617, China 1. department of Resource Exploitation Engineering China University of Mining and Technology 100083 Beijing China 2. beijing institute of Petrochemical technology 102617 Beijing China

The technology of 3. geological modeling will bring about great changes in the methods of geological data acquiring, storing, processing and displaying. However, no perfect or convenient software systems have been developed up to now since the geologic data which re-flect geological entities bear the feature of diversity, uncertainty and complexity. Some supervoxel models, mathematical models of fault and geometrical models of fold have been contrived so as to show the space geometric configuration of the complicated geologic structures. The application-oriented system architecture for 3. geological modeling is established; and a novel design concept based on spatial data processing is also proposed with the technology of solid modeling as its core and the application of models as its objective. Theories and methods for 3. geological modeling will hopefully be enriched and developed. In the light of these theories and methods, a feature-based navigation visualization technique is also put forward in the paper. By integrating geo-database, graphics libraries and KBS with 3. dynamic simulation systems, geologists will be able to capture the partial characteristics and whole structure embodied in the geological data in a direct-viewing, figurative and accurate manner.

关键词： 3. geological modeling,geometrical model,system architecture,visualization

Statistic characteristic analysis of forward scattering surface clutter in bistatic radar

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Science China(Information Sciences) 2010年第12期53卷 2675-2686页

作者： HU Cheng ,LONG Teng & ZENG Tao Radar Research Lab,department of Electronic Engineering,beijing institute of {3.,beijing 100081,China 1. Radar Research Lab Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China

In this paper,based on the processing results of measured forward scattering clutter data in bistatic radar,using the Gaussian distribution model,Exponential distribution model,Power-Law distribution model,high order Auto-Regressive model and so on,the probability density distribution and power spectrum mathematical model are obtained,and the impact of clutter statistic models on target detection performance is analytically derived from statistic *** to the estimated clutter probability distribution,power spectrum model and generalized matching filter theory,the forward scattering clutter in bistatic radar is effectively suppressed and the target motion parameters are accurately estimated from the measured clutter data.

关键词： bistatic radar forward scattering surface clutter clutter probability density function clutter power spectrum model target detection performance

Non-Noether conserved quantity for differential equations of motion in the phase space

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Chinese Science Bulletin 2002年第24期47卷 2049-2050页

作者： MEI Fengxiangdepartment of Applied Mechanics, beijing institute of technology, beijing 100081, China department of Applied Mechanics Beijing Institute of Technology Beijing China

A non-Noether conserved quantity for the differential equations of motion of mechanical systems in the phase space is studied. The differential equations of motion of the systems are established and the determining equations of Lie symmetry are given. An existence theorem of non-Noether conserved quantity is obtained. An example is given to illustrate the application of the result.

关键词： mechanical system phase space non-Noether conserved quantity.