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ON FrACTAL MECHANISM OF COASTLINE-A Case Study of china

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Chinese Geographical science 2002年第2期12卷 142-145页

作者： ZHU Xiao hua, WANG Jian(college of Geographical science,Nanjing normal university,Nanjing 210097,p.r.china) college of Geographical science Nanjing Normal University Nanjing 210097 college of Geographical science Nanjing Normal University Nanjing

MANDELBrOT enunciated the uncertainty of the length of a coastline in his paper"How long is the coastline of Britain?"published in "science" in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. According to the fractal theory and conditions of fractal research of coastline,the controls of faults and biologic function on the fractal character of coastline are preliminarily discussed on the basis of GIS in this paper . Finally,some significant conclusions are drawn:1)the faults control the basic trends of coastlines of two study areas;2)the fractal dimension of coastline of Taiwan is smaller than that of Changle-Lufeng,because the faults of Taiwan more intensely control the trend and fractal dimension of the coastline;3)the larger the fractal dimension of the faults or the major faults,the more the controlling effect of them on the trend and fractal dimension of coastline; 4)the larger fractal dimension of the coastline of Changle-Lufeng indicates that the biologic function intensely shapes the coastline. In a word,the controls of faults and biologic function on the fractal character of coastline are discussed with a case study of china in this paper,it can be seen that faults and biologic function both have influence over the trend and fractal dimension of coastline,the fractal mechanism of coastline of two study areas may be so.

关键词： fractal fractal dimension GIS faults biologic function coastline

ON THE LEAST SQUArES prOBLEM OF A MATrIXEQUATION

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Journal of Computational Mathematics 1999年第6期17卷 589-594页

作者： An-ping Liao(college of science, Hunan normal university, Changsha 410081, china) 湖南师范大学理学院湖南长沙 410081

Least squares solution of F=pG with respect to positive semidefinite symmetric p is considered,a new necessary and sufficient condition for solvablity is given,and the expression of solution is derived in the some special cases. Based on the expression, the least spuares solution of an inverse eigenvalue problem for positive semidefinite symmetric matrices is also given.

关键词： least squares solution matrix equation inverse eigenvalue problem positive semidefinite symmetric matrix

Moore-Smith Convergence in L-Fuzzifying Topological Spaces

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Journal of Mathematical research and Exposition 2011年第5期31卷 770-780页

作者： Wei YAO1,2, Ling Xia LU3 1. college of Mathematics and Information science, shaanxi normal university, shaanxi 710062, p. r. china 2. college of science, Hebei university of science and Technology, Hebei 050018, p. r. china 3. School of Mathematics and science, Shijiazhuang university of Economics, Hebei 050031, p. r. china college of Mathematics and Information science Shaanxi Normal University Shaanxi 710062 School of Mathematics and science Shijiazhuang University of Economics Hebei 050031

This paper presents a definition of L-fuzzifying nets and the related L-fuzzifying generalized convergence spaces. The Moore-Smith convergence is established in L-fuzzifying topology. It is shown that the category of L-fuzzifying generalized convergence spaces is a cartesianclosed topological category which embeds the category of L-fuzzifying topological spaces as a reflective subcategory.

关键词： L-fuzzifying topology L-fuzzifying filter L-fuzzifying net L-fuzzifying generalized convergence space topological category cartesian-closed.

preparation of Cu-SiO_2 composite aerogel by ambient drying and the influence of synthesizing conditions on the structure of the aerogel

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Chinese science Bulletin 2011年第7期56卷 685-690页

作者： LI GuiAn, ZHU TingLiang, DENG ZhongXun, ZHANG YaJuan, JIAO Fei & ZHENG Hairong college of physics and Information Technology, shaanxi normal university, Xi’an 710062, china college of physics and Information Technology Shaanxi Normal University Xi’an China

A copper-doped silica composite aerogel with high specific surface area was prepared using a sol-gel method at ambient pressure. A drying control chemical additive (DCCA) N,N-dimethylformamide (DMF) was introduced to the composite sol of tetraethyl orthosilicate (TEOS) and copper nitrate (Cu(NO3)2·3H2O) during the synthesizing process. The influence of the preparation conditions including Cu loading, catalyst concentration and heat treatment on the structure of copper-doped silica was investigated. The results showed that the obtained aerogel particles were uniformly distributed. The pore diameter was in a range of 2 to 15 nm. Heavier Cu loading benefited the formation of CuO crystalline, and reduced the specific surface area and pore diameter. When the catalyst concentration was high, the aggregation of Si-O network was reduced with the increase of it. The composite aerogel exhibited a good thermal stability after the heat treatment at high temperature.

关键词：复合气凝胶铜掺杂凝胶结构合成条件 Si02 常压正硅酸乙酯溶胶凝胶法

Scenario simulation and forecast of land use/cover in northern china

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Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3 & HE ChunYang 3 1 college of Geographical science, Chongqing normal university, Chongqing 400047, china 2 college of resources and Environmental science, Chongqing university, Chongqing 400044, china 3.college of resources science & Technology, Beijing normal university, Beijing 100875, china college of Geographical science Chongqing Normal University Chongqing China college of resources and Environmental science Chongqing University Chongqing China college of resources science & Technology Beijing Normal University Beijing China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back propagation Neural Network (BpNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BpNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BpNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BpNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

A study on the spatial flow intensity of overseas travelers in tourist hotspots of china──taking Beijing as an example

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Journal of Geographical sciences 2000年第1期10卷 79-83页

作者： ZHANG Hong, GUO Ying-zhi (college of Tourism and Environmental science, shaanxi normal university, Xi’an 710062 china, college of Management science, Fudan university, Shanghai 200433, china)

Through practical sampling survey for the overseas travelers in the 12 tourist hotspot cities of china, the analytical results of database of the spatial changes for overseas travelers have been established with the help of the software Visual Foxpro. The New concepts such as transferring state, which can be used to study the spatial flow intensity of travelers. is first put forward By analyzing the statistical results, the spatial flow intensity of 12 tourist hotspot cities in china for overseas travelers has been probed At last, a practical research of spatial flow intensity for overseas tourists is carried out in Beijing──the of tourist hotspots of china

关键词： overseas tourists, spatial flow intensity receiving index. transferring state. Beijing

Wave Solutions for the GinzburgLandau-BBM Equations (I)

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Communications in Nonlinear science and Numerical Simulation 1998年第4期3卷 218-221页

作者： Murong JIANG and Yawei TIAN(Department of Mathematics, Yunnan university, Kunming 650091, china)(Graduate School of china Academy of Engineering and physics, p.O.Box 2010 Beijing100081, china)(computer Department, shaanxi normal university, Xi’an 710062, Department of Mathematics Yunnan University Kunming 650091 China Graduate School of china Academy of Engineering and Physics P.O.Box 2010 Beijing 100081 China computer Department Shanxi Normal University Xi'an 710062 China

In this paper, the stability of plane wave solutions for the GinzburgLandau-BBM equations are considered. When the coefficients are suitably constrained,these waves are stable.

关键词： stability the Ginzburg- Landau- BBM equations plane wave solutions

The　photon　theory　hypothesis　about　photon　tunneling　microscope＇s　subwavelength　resolution

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光电子·激光 1996年第4期7卷 236-239+259页

作者： Yanbin Zhu Junfu Ma(Laser Li fe science Institute, South china normal university, Guangzhou 510631,p.r.china) 华南师范大学激光生命科学所广东广州

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关键词： tunneling hypothesis microscope about resolution subwavelength theory The photon

Symmetric Lévy Type Operator

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Acta Mathematica Sinica,English Series 2009年第1期25卷 39-46页

作者： Jian WANGSchool of Mathematical and computer science, Fujian normal university,Fuzhou 350007, p. r. china School of Mathematical and computer science Fujian Normal University Fuzhou P. R. China

The study of symmetric property in the L^2-sense for the non-positive definite operator is motivated by the theory of probability and analysis. This paper presents some sufficient conditions for the existence of symmetric measure for Lévy type operator. Some new examples are illustrated. The present study is an important step for considering various ergodic properties and functional inequalities of Lévy type operator.

关键词： Lévy type generator symmetric measure