Temporal reasoning with fuzzy time-objects

A novel approach to temporal reasoning is proposed which deals with both uncertain facts and uncertain temporal information in fuzzy logic. Fuzzy time-objects are defined to represent these uncertainties. A point of particular concern when reasoning with both kinds of uncertainty is that temporal uncertainty should not influence factual uncertainty. On the other hand temporal reasoning is exactly about the relation between time and fact. By introducing constrained time-objects we show that a relation between time and fact can be established while avoiding mixing of uncertainties. Then a method to reason with time-objects is introduced. The inference relation between time-objects is thereby decomposed in a fact-fact and a time-time relation. Such a decomposition is only allowed for (semi-) separable time-objects. The decomposition does not prevent time and fact to have mutual influence