Author(s):
1. Mladen Tomić, The School of Higher Technical Professional Education, Niš, Serbia
2. Mića Vukić , Faculty of Mechanical Engineering in Niš, Serbia
3. Predrag Živković, Faculty of Mechanical Engineering in Niš, Serbia
4. Žana Stevanović, University of Belgrade, Vinča Institute of Nuclear Sciences, Serbia, Serbia
5. Ivan Ćirić, Faculty of Mechanical Engineering in Niš, Serbia

Final paper