Hidetoshi Nonaka Masahito Kurihara Time-Frequency Decomposition in Gesture Recognition System Using Accelerometer. 1072-1078 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3213&spage=1072 2004 conf/kes/2004-1 KES db/conf/kes/kes2004-1.html#NonakaK04