Author(s):
1. Dušan Petković, Faculty of Mechanical Engineering in Niš, Serbia
2. Miloš Madić, Serbia
3. Goran Radenković, Faculty of Mechanical Engineering in Niš, Serbia
4. Predrag Živković, Faculty of Mechanical Engineering in Niš, Serbia
5. Mladen Tomić, The School of Higher Technical Professional Education, Niš, Serbia

Final paper