OWL-Time (formerly DAML-Time)

OWL-Time is an ontology for describing the temporal content of Web pages and the temporal properties of Web Services.

W3C notes on the time ontology and the time zone resource in OWL:

The publications on Temporal Aggregates (first one focuses on the first-order logic representation, embedding iCalendar recurrence sets, and natural language examples, while the second one focuses on the OWL representation of the ontology):

There is an "entry" sub-ontology of time in OWL, which is simpler than the full OWL-Time and provides most of the basic temporal concepts and relations that most simple applications would need, i.e., a vocabulary for expressing facts about topological relations among instants, intervals, and events, together with information about durations, and about dates and times. It allows temporal predicates to apply directly to events.

A time zone resource in OWL for the entire world.

Other related resources: