APPLYING PHOTOELASTICITY WITH OPTICAL MAGNIFICATION METHOD TO INCREASE PRECISION OF DETERMINING FRINGE ORDER UNDER MONOCHROMATIC LIGHT Journal title: Journal of Mechanical Engineering Research & Developments (JMERD) Authors: M.B.H Sitorus, Melvin Emil Simanjuntak, Agus Sigit Pramono, Henry Lumbantoruan, Udur January Hutabar... Subject(s):