oleh Novizon, Novizon , Dinata, Uyung Gatot S

oleh Syafii, Syafii , Darwison, Darwison , Dinata, Uyung Gatot S

oleh Laksono, Heru Dibyo , Dinata, Uyung Gatot S

oleh Laksono, Heru Dibyo , Dinata, Uyung Gatot S

oleh Latif, Melda , Hayati, Nuri , Dinata, Uyung Gatot S

oleh Suresti, Amna , Dinata, Uyung Gatot S , Hellyward, James , Wati, Rahmi

oleh Suresti, Amna , Dinata, Uyung Gatot S , Hasan, Alizar , Hellyward, James , Wati, Rahmi

oleh Bachtiar, Asep Neris; Department of Mining Engineering, Industrial Technology High School of Padang, Padang, 25171, Indonesia. , Pohan, Ahmad Fauzi; Department of Physics, Andalas University, Padang, 25163, Indonesia. , Ervil, Riko; Department of Industrial Engineering, Industrial Technology High School of Padang, Padang, 25171, Indonesia. , Yusti, Irwan; Department of Information System, Industrial Technology High School of Padang, Padang, 25171, Indonesia. , Santosa, -; Department of Agriculture Industrial Engineering, Andalas University, Padang, 25163, Indonesia. , Berd, Isril; Department of Agriculture Industrial Engineering, Andalas University, Padang, 25163, Indonesia. , Dinata, Uyung Gatot S; Department of Mechanical Engineering, Andalas University, Padang, 25163, Indonesia.