Author(s):
1. Ivan Ćirić, Faculty of Mechanical Engineering in Niš, Serbia
2. Vlastimir Nikolic, Faculty of Mechanical Engineering in Niš, Serbia
3. Milan Pavlović, College of Applied Technical Sciences Niš, 4. Miloš Simonović, Faculty of Mechanical Engineering in Niš, Serbia
5. Emina Petrovic, Faculty of Mechanical Engineering in Niš, Serbia