Traffic flow a study of the way to pedestrians and vehicles ( mainly ) in the individual or a column of law and to flow and flow velocity and density the traffic relationship between, in order to reduce traffic delays, accidents and road use efficiency of transport. first in the fifties. is the basis of the project and the new development areas. the study of the main methods are :①Any probability theory. that road traffic independent, vehicles are random, and assumes that all the traffic is a probability in the process of probability theory to the method of analysis ;②Fluid mechanics. The traffic, traffic flow of the volatility of the theory that a specific nature of a fluid, gas motion or sound, flood wave theory, macro with the changes, the evolutionary approach ;③Dynamics. that car, with the traffic flow, following cars gets back. their move forward with some regularity, thus obtained all the dynamics of the state of the differential equations. the two latter method is more promising is a major service for road traffic, traffic and the ability to the traffic accident. traffic signals control and eliminate the waiting line and wait.
Our present stage of city traffic problem is the social and economic development of the inevitable result, according to the central committee on economic and social development of the ninth five-year plan and the 2010 long-range objective will enter into our socialist modernization, stability and rapid expansion. the new period, the big city traffic delay, is not easy to expand and the new road will be able to solve the problem.
Modern city in the day a passenger at peak period, the highly centralized and flows same passenger flow phenomenon is now, low volume of transportation has cannot satisfy the people's needs. the degree of relative to other public transport, urban track of land and transport :pumping energy large energy savings, environmental pollution, noise, the per capita in the safe, comfortable and convenient and quick characteristics.
Modern city with its modernization needed to have a life of modern communications system, with the layout of urban development of a highly coordinated and comprehensive traffic arrangements. Recent should be made to the city traffic basic to the road network system, improving general public transport service quality of management and coordination with good planning, comprehensive traffic conditions, expanding development potentiality of focus in orbit traffic for the key public transport network to introduce a large, medium volume of passenger transport subway and s-bahn means of transportation.
The city and analysis of regional distribution as the basis of the road network system showed its absolute importance.
key word: traffic flow, spatial and temporal distribution, xerox network system xerox