Tilahun Yeshambel, Addis Ababa University, IT PhD program,Ethiopia.
tilahunyeshambel@gmail.com
Josiane Mothe, INSPE, Univ. de Toulouse, IRIT, UMR5505CNRS, France
josiane.mothe@irit.fr
Yaregal Assabie Addis Ababa University, College of Natural and Computational Science, Ethiopia
yaregal.assabie@yahoo.com