The main elements of traffic flow theory

The main elements of traffic flow theory are the application of probability theory, the application of queuing theory, the theory of traffic flow fluctuation and the theory of following vehicles. Using the dynamics method to study the vehicle queuing in a single lane where overtaking is not possible, the rear vehicle follows the front vehicle's driving state, and expresses and clarifies the theory with mathematical models. It is a microscopic analysis method because the object of investigation is the interrelationship of single vehicles in the process of traveling. In the continuous driving situation, after the car to maintain a certain safety distance with the car in front and often with the car in front of the change in speed, this change can be briefly expressed as:

After the car speed change - driver reaction sensitivity * speed change in front of the car

Changing this expression can be derived from a variety of speed and density of the traffic flow of the relationship between the expression. Therefore, as long as there is a traffic speed, flow of observation of statistical data, can be applied to the above theory, the establishment of a mathematical model to characterize the state of the traffic driving. Follow the theory is often used to examine the highway vehicle rear-end collision accidents, automatic control of traffic signals, and so on.

The probabilistic approach is applicable to the study of low-density traffic flow, while the hydrodynamic and kinetic approaches are applicable to the study of high-density traffic flow. Because the research results of traffic flow theory and the actual traffic phenomenon there is a gap, it is still difficult to apply. In the future, the research of traffic flow theory should turn to the development of application. In some countries, there are a large number of bicycles and motor vehicles on the road mixing situation, the study of bicycle flow and the interrelationship with motor vehicle flow, is a new topic of traffic flow theory research.