The Research On The Analysis And Optimization Of Jing-jin-ji Metropolitan Area’s Urban System Structure

The metropolitan area is an advanced form of the organizational structure of urban space, and it is the product of the certain stage of the urban development, it is also a new regional development model which is adapt to regional economic integration’s development needs and could improve regional competitiveness. Urban system is the urban groups composed by the cities that have different levels of scale、different division of functions、spatial distribution contact closely and depend on each other in a relative integrated region. Jing-jin-ji metropolitan area is a high degree of modernization of China’s northern metropolitan area and more developed industrial concentrated area, Therefore, in this important period of strategic opportunities, it is of great significance to the economic and social development of the metropolitan area to study how to seize the opportunity and construct a reasonable urban system structure.In this article, the combination of development of the urban system and the particular region of the "metropolitan area" will be studied, it analyzes the structure of urban system in the metropolitan area in the dynamic perspective. The structure of urban system in the metropolitan area will be studied mainly in five parts.The first part is the introduction, it mainly explains the background to the study of urban system in metropolitan area, the significance of the study, the research situation of the metropolitan urban system at home and abroad, and the research goal, content and method.The second part is the analysis of the history of the evolution of urban scale structure, summarizes the characteristics of the population size structure of the urban system, and uses the index of the four cities and11cities to study the changes of the first degree of the metropolitan cities, and analyzes that the problems of the metropolitan scale structure, describes the cause of the problems.The third part is the analysis of the history of the evolution of urban functional structure, at the first, it analyzes the functional changes in the structure of the cities, and then during the calculation of the entropy of each city and the functional specialization of the index, analyzes that the problems of the metropolitan functional structure, describes the cause of the problems.The fourth part is the analysis of the history of the evolution of urban spatial structure. at the first, it focuses on the current characteristics of the spatial structure, and then by means of non-agricultural population and GDP data, the by using the gravity model, it calculates the changes of the value of Beijing and Tianjin cities gravitational size, analyzes that the problems of the metropolitan spatial structure, describes the cause of the problems.The fifth part is the research on the countermeasures of metropolitan areas of urban system structure, at the first, it points out that the optimization goals of t metropolitan areas of urban system structure, then describes six countermeasures to optimize metropolitan areas of urban system structure.