Development of facial expression recognition by significant sub-region. - Sopa Potikanya; Tanissorn Lertpithaksoonthorn; Aslam Meechai; Rattiya Mungauamklang; Puckpoom Keaokao; Chamaiporn Sukjamsri; Chamaporn Chianrabutra; Theekapun Charoenpong (KST, 2016)