Concept of Transportation Entropy and Its Application in Traffic Signal Control

This paper introduces the notion of the transportation entropy as the measure of the system disorder and studies its application in traffic signal control. In particular, this paper shows firstly the similarity between the thermodynamic system and transportation system by regarding the vehicles as energy, which provides us the opportunity to introduce the entropy notion into the transportation context. The detailed analysis indicates that the transportation entropy presented in this paper is proportional to the sum of the traffic densities of all vehicles inside the network. It is known that for each vehicle, its traffic density limits the speed and hence prolongs the delay. Therefore, the transportation entropy can be considered as the measure of the system disorder. Furthermore, by using the theory of dissipative system, this paper presents the condition for traffic signal control to make the transportation system have the tendency to decrease its disorder. This condition is then applied in the framework of Model Predictive Control to construct a traffic signal control strategy. Finally, a system including four intersections is carried out to illustrate the results.