Affiliation: | 1. Department of Applied Mathematics, National Chung‐Hsing University, Taichung 402, Taiwan;2. Department of Mathematics Education, National Taichung University, Taichung 403, Taiwan;3. Department of Applied Mathematics, National Sun Yat‐sen University, Kaohsiung 804, Taiwan;4. Department of Computer Science and Engineering, National Sun Yat‐sen University, Kaohsiung 804, Taiwan |