Won-Hee Han Eun-Ha Song Laurence Tianruo Yang Jong Hyuk Park Young-Sik Jeong ACE: Active Emergence Call Service System for u-Lifecare. 126-131 2008 MUE http://doi.ieeecomputersociety.org/10.1109/MUE.2008.55 conf/mue/2008 db/conf/mue/mue2008.html#HanSYPJ08