An infrastructure-less occupant context-recognition in energy efficient building

Energy efficient building refers to building with an integrated system that is aware toward energy usage and has an effort to automatically reduce all electrical energy wasting by turning some unused devices off. In order to decide an appropriate decision, such a system needs surrounding contexts, such as location and activity that are obtained from sensors around the environment. We propose a novel infrastructure-less occupant context recognition, where we only need off-the-shelf sensors in a mobile device to recognize room occupancy. The idea is to derive the occupant context from user position gathered by real time Dead Reckoning (DR) technique on a mobile phone. Moreover, our system is able to control electrical devices based on the occupant context in certain room. Our experiments in a laboratory environment show that it can be really implemented and prospectively replacing Passive Infrared (PIR) sensors in occupancy detection due to smaller delay compared to 10 seconds timeout which is commonly determined by many energy-efficient systems based on PIR-sensor to reach the unoccupied state.