1. Department of Physics Faculty of Mathematics and Natural Sciences University of Riau Jl.Kampus Binawidya KM 12.5, Panam Pekanbaru Indonesia
2. Department of Industrial Engineering State Islamic University of Sultan Syarif Kasim Riau Jl. H.R. Soebrantas Km.15 Simpang Baru-Tampan Pekanbar Indonesia