State-space modeling based on principal component analysis and oxygenated-deoxygenated correlation to improve near-infrared spectroscopy signals. - Nguyen Duc Thang; Nguyen Huynh Minh Tam; Tran Le Giang; Vo Nhut Tuan; Lan Anh Trinh; Hoang-Hai Tran; Vo Van Toi (SoICT, 2013)