Time Space: Representing Historical Time for Efficient Event Retrieval
This chapter describes a computational tool designed to assist analysts in maintaining and analyzing the temporal contexts of events. Timebase is a program that indexes the time intervals corresponding to the durations of events data. The indexation scheme supports the efficient retrieval of those data. The primary need for Timebase follows from our need in RELATUS to represent and reason about time. Ordinal time relationships, specified in the semantic representation, are also necessary, as are procedures for updating the relationships and the interval relationships in Timebase. The pointer propagation problem is solved by reconceptualizing time itself. Instead of considering time intervals as segments of the time line, consider them as points in a two-dimensional Cartesian coordinate system. All superiors of any time interval are located in that portion of the temporal octant higher in the end dimension and lower in the start dimension.