Du Li Bharathan Balaji Yifei Jiang Kshitiz Singh A wi-fi based occupancy sensing approach to smart energy in commercial office buildings. 197-198 2012 BuildSys@SenSys https://doi.org/10.1145/2422531.2422568 conf/sensys/2012buildsys db/conf/sensys/buildsys2012.html#LiBJS12