According to embodiments of the disclosed subject matter in this application, a power management system with multiple voltage regulator may be used to supply power to cores in a many-core processor. The handheld computer performs timing operations for sensor warm up and also shutting down the sensor power during a period of user inactivity after no measurements are being acquired. The method also includes determining if said minimum voltage is between a lower limit voltage and an upper voltage limit. Work shift data may be grouped into categories according to an employers worker needs for specific shifts. epitaxial layer deposited thereon and having lower dopant concentration than the semiconductor substrate, and is configured to have a plurality of unit cell transistors formed in the N.