Temporal Properties of Repetitive Entities

摘要

Temporal entities are assertions (e.g. events, states) whose truth can be associated with time. An interesting problem in temporal reasoning is the problem of representing the fact that such entities are repeated over time. The problem has attracted some interest lately in the knowledge representation community. In this paper, we take a novel approach to the problem, which allows us to recognize repeated (or recurrent) entities as a class of temporal entities with well-defined properties. We derive some general properties for this important class of temporal entities, and some properties for an interesting subclass, namely the class of repetition of concatenable entities. Conacatenable entities have been called unrepeatable in the literature. As such we take a special interest in investigating their properties. The logical theory used here is a reified theory, which admits entity types, into its ontology as opposed to tokens, and uses Allen’s interval logic. Finally, we relate the new class of repetitive entities to existing classes in Shoham’s taxonomy.