1. Department of Systems Science, Kyoto University, Kyoto 606-8501, Japan, also with the Fakulti Kejuruteraan Mekanikal, Universiti Teknikal Malaysia Melaka, Melaka 76100, Malaysia, and also with the Centre for Advanced Research on Energy, Universiti Teknikal Malaysia Melaka, Melaka 76100, Malaysia (e-mail: amriksingh@utem.edu.my).
2. Department of Systems Science, Kyoto University, Kyoto 606-8501, Japan.