Abstract: In a drive device for driving an ultrasonic transmitter, a drive signal generating unit generates a drive signal for driving the ultrasonic transmitter, based on a base signal having a plurality of unit frequency signals arranged in a time series, corresponding to respective codes forming a code sequence. When a first unit frequency signal and a second unit frequency signal chronologically adjacent to it are switched in a discontinuously switching state that is different from a continuously switching state where the first and second unit frequency signals are switched such that a target frequency for a transmission frequency changes continuously at a substantially constant rate, the drive signal generating unit shifts the frequency in at least a switching portion immediately after start of the second unit frequency signal, in a same direction as a direction of frequency change from the first unit frequency signal to the second unit frequency signal.

Abstract: An automation system for train maintenance that performs operations related to train maintenance without human intervention is provided. The automation system for train maintenance comprises a refuse reservoir (10), a sewage tank (20), a water tank (30), and expanders (41, 42, 51, 61). In this automation system, when a railway vehicle is parked, the expanders (41, 42, 51, 61) are expanded to lift connectors (45, 54, 64) toward the railway vehicle for connection to the refuse reservoir (10), sewage tank (20), and water tank (30). In this automation system, discharge of refuse, removal of sewage, and feeding of water are automatically performed. Upon completion of these operations, the expanders (41, 42, 51, 61) are contracted so that the connectors (44, 45, 54, 55, 64, 65) are stored in waiting locations (48, 58). Therefore, use of this automation system for train maintenance allows automatic train maintenance without human intervention.

Abstract: An automation system for train maintenance that performs operations related to train maintenance without human intervention is provided. The automation system for train maintenance comprises a refuse reservoir (10), a sewage tank (20), a water tank (30), and expanders (41, 42, 51, 61). In this automation system, when a railway vehicle is parked, the expanders (41, 42, 51, 61) are expanded to lift connectors (45, 54, 64) toward the railway vehicle for connection to the refuse reservoir (10), sewage tank (20), and water tank (30). In this automation system, discharge of refuse, removal of sewage, and feeding of water are automatically performed. Upon completion of these operations, the expanders (41, 42, 51, 61) are contracted so that the connectors (44, 45, 54, 55, 64, 65) are stored in waiting locations (48, 58). Therefore, use of this automation system for train maintenance allows automatic train maintenance without human intervention.