Information Mechanism Of Spatial Structure Change In Urban Groups

With the rapid development of urbanization and the full speed expansion of the megalopolis, urban environment problem is serious day after day, the contradiction between urban construction and the agricultural land intensifies, people urgently demand to strengthen the research of technologies and methods of urban planning and management. The forming and the evolution of the urban groups' spatial structure, the expansion of the urban land use space and the information mechanism of urban groups' spatial structure are becoming the new and hot problems of the geographical academe, urban planning academe, remote sensing scientific academe, geographical information scientific academe, etc. They are also the important issues which administration and supervision authorities pay close attention to very much. Because of the interaction between cities, gathering and spreading and complex urban background in the dense urban area, the research of the spatial expansion and land use potentiality of single city becomes more difficult, the difference between the research results and reality is relatively great.Regarding urban groups as the research object, this paper structures the frame that the urban groups' spatial structure evolves on the basis of the information mechanism. It explains the evolution of the urban groups' spatial structure of Wuhan after liberation, especially in society, economy, ecological environment in the past 10 years, this kind of change deeply brands on the pattern of land use. High economic growth causes the big city to expand rapidly, the small and medium-sized cities (town) develop rapidly, all these have established the foundation for the perfection of the urban system. The urban groups is taking shape or have taken shape, or evolve for advanced stage. Therefore, it has very important meaning for this thesis to research the information mechanism of the urban groups', spatial structure change.The research goal of this paper is to provide information of reflecting urban groups' spatial structure for department leader and high level leader and of its change. So, this paper will do the research of relative theory, technology, method and application. It utilizes the existing map information to do correction of multi-time remote sensing images and image classification based on the evidence theory, then to draw thematic information of built-up area. Based on this , proposition logic calculation method , information entropy, center of gravity moving, position changing of the land use are used to study the evolution of urban groups' spatial structure of Wuhan, and to analyse and predict urbanization level in Wuhan based on population information and economic information with grey theory.The information mechanism of the urban groups' spatial structure change is to study the spatial information mechanism of the earth from region. It opens out the urban groups' spatial structure geometry shape, the spatial distribution, spatial combination, spatial interaction and changing rule based on the understanding and analysis of urban groups' spatial information. The article starts from the concepts of urban groups' spatial structure , information mechanism, analyses the composition elements of the urban groups' spatial structure, discusses theoretical foundation and research approach of urban groups' spatial structure, and basic principle of the urban groups' spatial structure evolution, makes certain the technological route of studying urban groups spatial structure.It analyses different remote sensing data source and application, puts forward the method of remote sensing data fusion based on evidence theory. It studies various kinds of methods of the remote sensing image classification, proposes the categorised method of remote sensing image based on evidence theory and compares the classification precisions. Then we draw out the thematic information of built-up area which we pay close attention to from the categorised result. It summarizes the information mechanism which reflects the urban groups' spatial structure evolution, such as shape, area, centre of distribution, position and direction of built-up area, information entropy of land use, etc.It proposes proposition logic calculation method to analyse the evolution of urban groups' spatial structure based on information mechanism. The article uses grey theory to analyse and predicte the urbanization level of Wuhan.Finally, on the basis of theoretical research, the paper studies the evolution of urban groups' spatial structure of Wuhan from several respects of information mechanism, summarizes the rule of urban groups' spatial structure evolution of Wuhan, which expandes from centre of the city to outer lane layer, and toward the west and the north of the city acceleratly. This provides the scientific basis and theoretical foundation for planning and making out counter-measure of urban groups' spatial structure of Wuhan.The main content of this paper includes the following two respects: theoretical research and application research.On the theoretical hand, this paper systematically researches many theoretical issues, including theory of urban spatial structure change, theory and method of data fusion, image classification theory, spatial analysis theory, evidence theory, mathematical logic, system theory, information theory and grey theory. It introduces these theories and methods to information mechanism of urban groups' spatial structure evolution. According to real request, these methods are improved. It excogitates multi-band data fusion method and image classification method based on evidence, proposition logic calculation method, land use information entropy and grey theory analysis method.On the application hand, taking urban groups of Wuhan as research object, this paper applies these theories and methods to analyse and research change of urban groups' spatial structure of Wuhan, including spatial quantity and quality change, such as spatial distribution gravity moving, spatial development direction and information entropy change. It analyses and predicts all districts' urbanization level based on grey theory, proposes the idea of redistribution of urban groups' spatial structure of Wuhan.