A system, method, and computer program product are provided for automatically segmenting input document images into regions of black text, white space, and image content. A schedule publication element acquires information about user schedules. The claim about occupancy is optionally visually displayed as the vehicle traverses the highway. This configuration allows a stray capacitance value of a transmissionreception path to be reduced at the time of transmissionreception, thereby obtaining a favorable radio-frequency characteristic.