Masakatsu Mitani Mamoru Takaya Atsuhiro Kojima Kunio Fukunaga Building Maps of Unknown Environment through Observation of Human Actions. 310-313 2006 conf/icicic/2006 ICICIC (1) http://doi.ieeecomputersociety.org/10.1109/ICICIC.2006.59 db/conf/icicic/icicic2006-1.html#MitaniTKF06