1. Department of Mechanical, Production and Energy Engineering, Moi University, Eldoret P.O. Box 3900-30100, Kenya
2. Faculty of Engineering and Technology, University of Buea, Buea P.O. Box 63, Cameroon
3. Laboratory of Electrical Engineering and Computing (LEEC), University of Buea, Buea P.O. Box 63, Cameroon
4. Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, 1433 Ås, Norway