1. Department of Mathematics, Shanghai Normal University, Shanghai People's Republic of China
2. Department of Mathematics, Babeş-Bolyai University Cluj-Napoca and Academy of Romanian Scientists Bucharest, Romania
3. General Education Center, National Yunlin University of Science and Technology, Douliou, Taiwan
4. Research Center for Interneural Computing, China Medical University Hospital, Taichung, Taiwan
5. Department of Applied Mathematics, National Sun Yat-sen University, Kaohsiung, Taiwan