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School of Information Engineering Knowledge Engineering 2011–12 Solutions of Test 4 – 24th September 2012 1 8 pt Explain the concept of reasoning service. Classify and briefly describe all main reasoning services. Specify to which reasoning service all other reasoning services can be reduced; then show how the reduction can be concretely accomplished on a service of your choice. See the Lecture Notes 2011–12, Sections 4.2 and 4.3. 2 14 pt Translate the requirements below into OWL 2 DL, using the DL notation. Specify the domain and range of every property. In case a requirement cannot be specified in OWL 2 DL explain why, and if possible provide an OWL 2 DL approximation. Avoid redundancies (i.e., do not state again what can already be derived) and use ABox assertions whenever possible. 1. a temporal entity can only be an instant or an interval (but not both things at the same time); 2. to every instant exactly one “date” (data of type xsd:dateTime) is associated; 3. every interval has exactly one start instant and exactly one end instant; 4. an instant may be “before” or “after” another instant, where each of the two properties is the inverse of the other; 5. if x is before y and y is before z, then x is before z; 6. the start instant of an interval is before the end instant of the same interval; 7. if instant x is after the start instant of interval y and before the end instant of y, then x is internal to y; 8. every interval has at least one internal instant. Now formulate the following DL queries. For each such query say which reasoning service is invoked, give the answer that would be derived, and briefly justify it. If the query cannot be formulated in OWL 2 DL explain why and, if possible, provide an OWL 2 DL approximation. 9. no interval has a date; 10. it is…