Abstract: After the air pressure of the tire of the vehicle has decreased to a predetermined abnormal value, the system management server determines that the vehicle has returned to a normal value without performing a tire replacement operation or a tire repair operation (for example, there is a driver that continuously drives the vehicle by replenishing air without performing a tire replacement even if the tire is punctured), and transmits abnormality notification information to the administrator terminal device. Thus, the warning information is provided to the current driver of the vehicle by the operation of the administrator terminal device by the administrator.

Abstract: Provided are a shift position sensor detecting a shift position of a vehicle; a yaw rate sensor detecting a yaw rate of the vehicle; a turning angle calculation unit calculating, based on the yaw rate between a start time and an end time of a first time, a turning angle of the vehicle in a plan view between the start time and the end time; and a determination unit determining that the vehicle executes a specific retreat operation when the determination unit determines, based on a detection value of the shift position sensor, that the shift position is switched to an advance position, a reverse position, and the advance position within the first time, and a maximum cumulative value of the turning angle of the vehicle in one direction between the start time and the end time, calculated by the turning angle calculation unit, is a threshold value or more.