Institute of Traffic Engineers (ITE) defines traffic engineering as a subset of transportation engineering. The definition given is as follows: "Traffic Engineering is that phase of transportation engineering which deals with the planning, geometric design and traffic operations of roads, streets and highways, their networks, terminals, abutting lands, and relationship with other mode of transportation". The objective of traffic engineering is to provide for the safe, rapid, comfortable, efficient, convenient, and environmentally compatible movement of people, goods, and services. The revolution in the automobile industry and liberalized economy has led to tremendous increase in the vehicle ownership levels. With the development of urbanization and motorization, the imbalanced contradiction of urban traffic between supply and demand becomes increasingly sharp. Traffic congestion has become a serious "urban illness", and it results in problems such as travel time delay, increase of traffic accidents, rise of fuel depletion, survival environmental degradation and so on. It severely affects the city's normal function and its sustainable development.