1. a Traffic Research and Survey Group, Planning Department , Hanshin Expressway Co. , Osaka, Japan
2. b Information System Planning Group, Information System Department , Hanshin Expressway Co., Ltd. , Osaka, Japan
3. c Institute of Urban Transport Planning Co., Ltd. , Osaka, Japan
4. d Graduate School of Science & Technology , Kobe University , Kobe, Japan
5. e Graduate School of Engineering , Kobe University , Kobe, Japan