Alberto Calatroni Claudia Villalonga Daniel Roggen Gerhard Tröster Context Cells: Towards Lifelong Learning in Activity Recognition Systems. 121-134 2009 EuroSSC http://dx.doi.org/10.1007/978-3-642-04471-7_10 conf/eurossc/2009 db/conf/eurossc/eurossc2009.html#CalatroniVRT09