DATA STRUCTURE, POSITION INFORMATION SERVER, POSITION INFORMATION REGISTRATION RETRIEVING METHOD AND ITS PROGRAM

PROBLEM TO BE SOLVED: To make information related to a position and a time usable by a wide range of application by managing the information hierarchically. SOLUTION: Hierarchized position information (L1 to L5) shows a data structure set in a database 23 of a position information server 2. The information of L1 is position information and time information being an effective period of the information of the other layer. The coordinate system is latitude and longitude, or latitude, longitude and altitude. The information of L2 is information about a position fixed in the coordinate system. The information of L3 is a name that does not exist in the coordinate system. The information of L4 is event information that depends on a position and a time. The information of L5 is freely settable information. Two or more pieces of information are decided among the position information of L1, the information of L2, the information of L3, the information of L4 and the information of L5, and the two or more pieces of information are associated. When associated with information of another layer, time information of L1 shows the effective period of the information. COPYRIGHT: (C)2007,JPO&INPIT