Author(s):
1. Novak Nikolić, Faculty of Engineering, University of Kragujevac, Sestre Janjić 6, 34000 Kragujevac, Srbija 2IMW Ins, Serbia
2. Nebojša Lukić, Fakultet inženjerskih nauka Univerziteta u Kragujevcu, Serbia
3. Dragan Taranović, Faculty of Engineering, University of Kragujevac, Sestre Janjić 6, 34000 Kragujevac, Srbija 2IMW Ins, Serbia