A method and apparatus for efficiently deriving modulo arithmetic solutions for frequency selection in transceivers. By separately managing the manner of notification provided to the user from its associated content, the personal hub may give a user more control over a number of mobile devices by allowing the user to escalate or dismiss different notifications across one or more mobile devices. A middle electrode is formed between the memory element and the switch element. A second insulating film is formed on the side wall faces of the first and second contact holes. The control system includes a throttle operator, an operator position sensor, a controller and an actuator. A first eccentric cam and a second eccentric cam rotate to press down the recording sheet tray.