1. Department of Information Science and Control Engineering, Nagaoka University of Technology, Niigata, Japan
2. Department of System Safety Engineering, Nagaoka University of Technology, Niigata, Japan
3. Department of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo, Henan, P. R. China
4. Department of Infomation Science, Kaishi Professional University, Niigata, Japan