| 摘要 |
PROBLEM TO BE SOLVED: To provide route information with satisfactory efficiency by taking into consideration a change in terms of time in the price of a commodity in the search of a route for purchasing the commodity. SOLUTION: In a network navigation center 10, present-position information API and purchase-plan information PPI which is constituted of commodity-name data on the commodity desired by a user for its purchasing and start-scheduled- date data on a present place are received via a portable telephone base station 14 and a general telephone network 16 from a mobile communication device 12 mounted on an automobile 11. The center 10 retrieves purchase route information PRI on the basis of the information API and the information PPI so as to be transmitted to the device 12 via the network 16 and the station 14. The information PRI is constituted of guidance-route data on a guidance route to a store selling the commodity and detailed information data on the distance, the required time, the cost or the like of the guidance route, and it is displayed on a display 43 at the device 12 so as to be confirmed by the user. |
