1. a Maritime Faculty, University of Montenegro , Dobrota 36, 85330 Kotor , Serbia & Montenegro
2. b Department of Distribution Management , Tongmyong University of Information Technology , 535, Yongdang-dong, Nam-gu, Busan , 608-711 , Korea
3. c Faculty of Transport and Traffic Engineering , University of Beograd , Vojvode Stepe 305, 11000 , Beograd , Serbia & Montenegro