1. Faculty of Mechanical Engineering, University of Maribor Smetanova 17, SI-2000 Maribor, Slovenia,
2. Faculty of Mechanical Engineering, University of Maribor Smetanova 17, SI-2000 Maribor, Slovenia
3. Department of Mechanical Engineering, University of Aveiro 3810-193 Aveiro, Portugal, Faculty of Mechanical Engineering Technical University of Malaysia, 81310 UTM Skudai, Johor, Malaysia