Engineering a formal representation of complex temporal Information using the Web Ontology Language

Ontologies, a common approach for knowledge representation, encounter challenges in effectively handling time expressions, particularly in languages like OWL. Despite various proposed mechanisms for achieving consistent time representation within a single ontology, OWL-Time constructs have limitations in modelling complex recurring time expressions, crucial for domains such as clinical or historical. Hence, extending the OWL framework to represent recurring temporal information identified in domain-specific challenges is necessary. This paper enriches OWL-Time with the concept of recurring time by identifying five recurring time-related problems namely strongly, nearly, intermittent, non-recurring, and stochastic recurring time, covering the spectrum in classical ontologies. We propose BOLA as a novel ontology, extending OWL-Time's primitive entities, calendar descriptions, and introducing a new concept for recurring time rules. This extension creates 33 core temporal classes, offering a comprehensive representation within OWL-Time constructs. We evaluate the ontology's completeness, expressiveness, and complexity. Experimental results show that BOLA effectively represents a wide range of complex recurring temporal information within OWL-Time constructs, achieving completeness scores of 87 and 88 for class and property coverage hierarchy, expressiveness score of 13 for complex expressions with 49 cardinality restrictions, and a complexity reflection of 266 axioms, including 123 logical axioms.