PhD, Aizu Research Cluster for Medical Informatics and Engineering (ARC-Medical), Research Center for Advanced Information Science and Technology (CAIST), The University of Aizu, Aizuwakamatsu, Fukushima 965-8580, Japan. tdpham@u-aizu.ac.jp.|PhD, Aizu Research Cluster for Medical Informatics and Engineering (ARC-Medical), Research Center for Advanced Information Science and Technology (CAIST), The University of Aizu, Aizuwakamatsu, Fukushima 965-8580, Japan. tdpham@u-aizu.ac.jp.