1. Kaunas University of Technology , Faculty of Mechanical Engineering and Design, Department of Production Engineering , Studentu 56 , , Kaunas , Lithuania
2. Riga Technical University , Faculty of Materials Science and Applied Chemistry, Institute of Design Technologies , Kipsalas 6 , , Riga , Latvia
3. Riga Technical University , Technical Physics Institute , Kipsalas 6 , , Riga , Latvia