1. Textile College Zhongyuan University of Technology Zhengzhou 451191 P. R. China
2. School of Materials Zhengzhou University Zhengzhou 450052 P. R. China
3. Textile College Jiangnan University Wuxi 214112 P. R. China
4. Department of Functional Machinery & Mechanics Shinshu University Ueda Nagano 390‐8621 Japan