1. Y.B. Li, Y.X. Zhi and X.K. Wang: Machinery Manufacturing, (2007) No. 5, pp.64-65. (In Chinese).
2. X.D. Yang: Industrial Design Procedures and Methods, (Higher Education Press, China 2008). (In Chinese).
3. K.T. Urich and S.D. Eppinger: Product Design and Development, (Higher Education Press, China 2005). (In Chinese).
4. W. Guo and M.Y. Hu: Computer Integrated Manufacturing System, (2004) No. 9, pp.1165-1170. (In Chinese).
5. R. Wang and L. Wang: Modern Manufacturing Engineering, (2003) No. 10, pp.19-21. (In Chinese).