TOQL: Temporal ontology querying languageTOQL: Temporal ontology querying language Περίληψη Δημοσίευσης σε Συνέδριο Conference Paper Abstract 2015-11-012009enWe introduce TOQL, a query language for querying time information in ontologies. TOQL is a high level query language that handles ontologies almost like relational databases. Queries are issued as SQL-like statements involving time (i.e., time points or intervals) or high-level ontology concepts that vary in time. Although independent from TOQL, this work suggests a mechanism for representing time evolving concepts in ontologies based on the four-dimensional perdurantist mechanism. However, TOQL prevents users from being familiar with the representation of time in ontologies. To show proof of concept, an application has been developed that supports translation and execution of TOQL queries on temporal ontologies combined with a reasoning mechanism based on event calculus. A real world temporal ontology is also implemented on which several TOQL example queries are processed and discussed.http://creativecommons.org/licenses/by/4.0/338-35411th International Symposium on Spatial and Temporal Databases Petrakis Evripidis Πετρακης Ευριπιδης Papadakis Nikolaos Παπαδακης Νικολαος Nikolaos Maris Sotiris Batsakis Evdoxios Baratis Springer Verlag