Correspondence:

Saša Živanović, full professor, szivanovic@mas.bg.ac.rs (011) 3302 423
Milos Pjevic, assistant professor, mpjevic@mas.bg.ac.rs

Faculty of Mechanical Engineering, Kraljice Marije 16, 11120 Belgrade
phone (+381 11) 3302-423, fax 3370364
E-mail: jupiter@mas.bg.ac.rs