[1] Univ Putra Malaysia, Dept Elect & Elect Engn, Serdang 43400, Selangor, Malaysia
[2] Kaduna State Univ, Dept Phys, Tafawa Balewa Way,PMB 2339, Kaduna, Nigeria
[3] Univ Putra Malaysia, Inst Adv Technol, Serdang 43400, Selangor, Malaysia
[4] Univ Putra Malaysia, Dept Phys, Serdang 43400, Selangor, Malaysia
[5] Univ Putra Malaysia, Dept Chem & Environm Engn, Serdang 43400, Selangor, Malaysia