A.-H. LiaoC.-C. ShenPAI-CHI LI2018-09-102018-09-102009-09http://scholars.lib.ntu.edu.tw/handle/123456789/352555Contrast Improvement by Combining Pulse Inversion with EMD and EEMDconference paper10.1109/ULTSYM.2009.54419482-s2.0-77952840061