Andanastuti Muchtar
* Corresponding Author
Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Malaysia Fax: 603-89259659

Norazmira Wati
Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Malaysia Fax: 603-89259659

Nor Azri Jaafar
Department of Mechanical and Materials Engineering, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Malaysia Fax: 603-89259659