In one embodiment, the alert actions are preprogrammed and stored in the memory 320 of the subscriber device 300, and when a match is found between the current location and the geofence, the processor 310 reads the alert actions from the memory 320 to control the alert-generation device 370 to perform the alert actions.

In one embodiment, the alert actions are transferred from the remote management server 20 to the subscriber device 300 of each vehicle 30a to 30d through the alert action information field 520 in the safety warning signal 500b, as depicted in FIG. 3B. In this case, the processor 310 controls the alert-generation device 370 to perform the alert actions, as instructed in the alert action information field 540.

In one embodiment, the geofence can dynamically be adjusted in size or shape according to a working mode of the EV 10. For example, when determining the geofence for the EV 10, the processor 210 of the remote management server 20 dynamically changes the shape or size of the geofence based on the working mode of the EV 10. The working mode of the EV 10 can be selected (or determined) at the EV 10 or the remote management server 20. In case the working mode is selected at the EV 10, the selected working mode is provided in the working mode selection signal 14 and transmitted to the remote management server 20 over the communication network 15.