| 摘要 |
<P>PROBLEM TO BE SOLVED: To more appropriately update indication of estimated time of arrival. <P>SOLUTION: Residual estimated time required TRest from a current place up to a destination is calculated (S170), actual time required TAact from a departure place up to the current place is acquired (S190) and actual estimated time required TAest corresponding to a section from the departure place up to the current place out of estimated time required TTest is calculated (S200). When a determination rate Rt which is a rate of difference time ΔTA between the actual time required TAact and actual estimated time required TAest to the residual estimated time required TRest is a determination threshold Rref or more (S240), indication of estimated time of arrival ETA is updated based on the residual estimated time required TRest and current time (S260), and when the determination rate Rt is less than the determination threshold Rref, the indication of the estimated time of arrival ETA is not updated. When accuracy of prediction is low even when the estimated time of arrival ETA is estimated, updating of indication of the estimated time of arrival can be suppressed. <P>COPYRIGHT: (C)2013,JPO&INPIT |
