Managing Efficiently Temporal Relations Through Indexed Spanning Trees
نویسندگان
چکیده
We are interested here in the design of a very efficient Time-Map Manager, able to deal with a large knowledge-base of several thou sand time-tokens in demanding applications such as reactive planning and execution con trol. A system, called IxTeT, aiming at that goal is described. It uses an original represen tation of a lattice of time-points that relies for efficiency on a maximum spanning tree of the lattice together with a particular indexing of its nodes. The IxTeT system is sound and complete, it has the same expressive power as the restrict ed Interval Algebra that permits complete ness in polynomial time. Its average complexi ty is shown experimentally to be linear, with a low overhead constant, for both operations: retrieval in and updating of a set of temporal relations.
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