1. College of Engineering, Kombolcha Institute of Technology, Wollo University, Kombolcha P.O. Box 208, Ethiopia
2. Faculty of Civil and Water Resource Engineering, Bahir Dar Institute of Technology, Bahir Dar University, Bahir Dar P.O. Box 26, Ethiopia
3. School of Research and Graduate Studies, Arcada University of Applied Sciences, Jan-Magnus Jansson Aukio 1, 00560 Helsinki, Finland