This author has not been identified. Look up 'Heng Zhang' in GoogleThis author has not been identified. Look up 'Zhiping Cai' in GoogleThis author has not been identified. Look up 'Qiang Liu' in GoogleThis author has not been identified. Look up 'Qingjun Xiao' in GoogleThis author has not been identified. Look up 'Yangyang Li' in GoogleThis author has not been identified. Look up 'Chak-Fong Cheang' in Google