Affiliation: | Dr. G. Simi?() is a professor and Dr. V. Lu?anin () is a professor at the University of Belgrade–Faculty of Mechanical Engineering, Department of Railway Mechanical Engineering, Belgrade, Serbia.; . J. Tanaskovi?() is in the "GO?A Institute" d.o.o., Smederevska Palanka, Belgrade, Serbia.; . Dr. N. Radovi?() is a professor at the University of Belgrade–Faculty of Technology and Metallurgy, Department of Metallurgical Engineering, Belgrade, Serbia. |