Empirical Approach for Road Traffic Flow Analysis on the Basis of Fuzzy Set Theory

Abstract

The traffic assignment is regarded as the most important estimation technique of traffic flow in urban network planning. In this study, traffic assignment models with fuzzy travel time are introduced. The applicability of the proposed model is investigated with empirical data. Firstly, the shape of the membership function for fuzzy travel time is considered from the data in the road traffic census and the road user questionnaire survey. Secondly, two different methods such as a removal model and a gravity model are proposed to represent fuzzy numbers. Both models estimate traffic flow with representative value of fuzzy travel time. They can be formulated as extensions of an equivalent mathematical programming for conventional atraffic assignment. Lastly, the models are applied to analyze the traffic flow on the network of Kyoto city as a real scale ezample. Particularly, the models are confirmed to be practical with consideration of the relation between observed values and estimated values for traffic in different types of roads.As the results of the study, it is concluded that the proposed models enable to describe the perception of drivers for travel time information and they can provide the practical estimation of traffic flows.