[1] Botswana Int Univ Sci & Technol BIUST, Fac Engn & Technol FET, Dept Mech Energy & Ind Engn, Private Mail Bag 16, Palapye, Botswana
[2] BIUST, Dept Chem Mat & Met Engn Acad, FET, Private Mail Bag 16, Palapye, Botswana
[3] Natl Univ Malaysia, UKM, Fac Engn & Built Environm, Dept Mech & Mat Engn, Bangi 43600, Malaysia
[4] Botswana Inst Technol Res & Innovat BITRI, Private Bag 0082, Gaborone, Botswana