Abstract
Falling objects on highways is one of the direct or indirect factors which induce a major accident. Therefore, in management of highways, the improvement in visibility to falling objects has been an important issue. And, the reflectance distribution of falling objects and the tunnel lighting system greatly influence improvement in the visibility of falling objects. In this study, it is set the eventual goal that the establishment of the decision making of the tunnel lighting system, and as its basic study, it is precisely estimated the reflectance distribution. Specifically, it is represented the reflectance distribution by beta mixture model that can be considered the multimodal and estimated mixing coefficient and unknown parameters of beta mixture model with the aid of the EM algorithm. Finally it is indicated the application example which used the survey data, and verified of the validity of the model in this study.
