Relating Microscopic Parameters to Macroscopic Characteristics of Transitional State Traffic Flow by Time Headway

Relating the microscopic parameters to the macroscopic characteristics of traffic flow by mechanism deduction can make the calibration of the microscopic parameters conveniently and efficiently. The corresponding researches of the steady state flow have been reported in the literature. However, as the steady states are easy to be broken by disturbances and other factors, the actual traffic flow is difficult to keep steady. The actual traffic flow is often in the processes moving from one steady state to another, which can be called the transitional states. Therefore, the transitional states are more accordant with facts and investigated. For transitional state, time headway is employed as an intermediate variable to relate the microscopic parameters to the macroscopic characteristics in this paper. The experiments results verify the relationships established in this paper.