Implementations relate to methods and apparatus for the aggregation of guide and frequency map information for multiple frequency networks using an upper-level single frequency network. The electronic apparatus has first and second groove portions that are formed on a first surface and a second surface of a heat sink, respectively. An allowable range is determined for the voltage command value based on the load value and physical quantity associated with an operating condition of the motor. Once the data signal bandwidth capability of the memory storage device is determined, the memory storage device is segmented to improve utilization of the data signal bandwidth capability.