Virtual Space Theory And Its Application In The Analyses Of Urban Spatial Convergence-Diffusion

Along with the quick urbanization course in these several decades,the structure of urban space transformed rapidly. New complexion appears in its development and research trend. First, in the development history of the urban spatial structure, convergence and diffusion are always the basic form of the urban spatial movement, and they are also the zealous object to research people in the field of urban spatial structure, so, the research about urban spatial structure always base on convergence and diffusion movement. Secondly, urban space is developing to the non-geography spatial direction. On one hand, along with the era of new technology revolution , the age of information, the maturation of web technology, dummy space has its own room in the urban space; On the other hand, the development of traffic carrying trade, the advancement of traffic technology and the levity of urban traffic status now, all of these make the traffic speed and the viatic attainability be the factors that influence or even restrict the dimensions of urban space and the development of urban spatial function. In the research course of urban spatial structure, the important station of the traffic speed protrudes increasingly, and inside the urban, the traffic time which is decided by traffic speed has more important practice meaning than traffic distance in the research of the urban spatial structure. The influence of real geography space to urban spatial structure development wear off, urban spatial structure is developing to the non-geography spatial direction gradually.This paper bases on these two characteristic of urban spatial structure development and research, starts off with the urban spatial basic development form--convergence and diffusion, and new visual angle of urban spatial structure research--urban virtual space, then researches urban spatial structure, and combine these two results together. So, this paper includes three aspects: urban spatial convergence-diffusion research, urban virtual space research, and the application of virtual space theory in urban spatial convergence and diffusion.The analyses of urban spatial convergence --diffusion: one of the methods of basic research of urban spatial structure development. This paper quantifies urban spatial convergence -diffusion, defines the index of urban spatial convergence-diffusion analyses, provides an effective path to advance the application of urban spatial convergence-diffusion analyses in urban planning; The analyses of urban virtual space: this paper aims at the influence to urban spatial structure by traffic speed and viatic attainability, utilizes the traffic speed as medium, transform urban geography space to urban time space, uses urban time space to weigh and value the rationality of the urban space planning. This method has the active meaning and realism rationality at present.As the transformation of research result to practice application, and bases on the research result of virtual space theory in this paper, this paper bring forward a kind of map --"time map", which uses time as reference axis. And this paper adopts a stimulant example to demonstrate the principle, time map making process and the application of time map in urban spatial convergence-diffusion analyses in detail.The accelerate of urbanization process, the inburst of population to urban, the era of information and the influence of urban traffic status, are not only opportunity but also challenge to the development of urban spatial structure. Adopting rational method to support urban space planning is pressing, bases on this requirement, this paper does some research and discussion, expects to provide an effective method to urban spatial structure.