I'm creating a OWL ontology with Protégé, in which I need to work with
i.e. using two datatype attributes: valid_from, and valid_until, whose value
in years (preferably) or complete data (dd/mm/yy or some other format).
Since the ontology contains all objects (instances that are still valid and
those that are no longer valid), I want to be able to filter, for any point
of time t,
all instances valid at t. Where t can be, again, a year or date.
In practice I need something to work with time intervals.