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School of Information Engineering Knowledge Engineering 2011–12 Solutions of Test 2 – 16th July 2012 1 8 pt. Define all possible forms in which a class can be described in SROIQ(D). For each such form specify the DL syntax and the formal semantics, and explain the intuitive meaning in English or Italian. (For the sake of brevity, do not take into account class descriptions based on data properties.) Lecture notes, chapter 3. expression name formal semantics intuitive meaning A a basic class any set A I ⊆ ∆ a s e t o f o b j e c t s ⊤ t h e t o p c l a s s ∆ every object of the universe ⊥ t h e b o t t o m c l a s s ∅ no object ¬C class complement ∆ \ CI t h e o b j e c t s t h a t a r e n o t C (C ⊓ D) class intersection C I ∩ DI t h e o b j e c t s t h a t a r e C a n d D (C ⊔ D) class union C I ∪ DI t h e o b j e c t s t h a t a r e C o r D ∃R.C existential restriction {x ∈∆ | for some y∈CI: 〈x,y〉∈RI} the objects that are R-related to some C ∀R.C universal restriction {x ∈∆ | if for some 〈x,y〉∈RI, then y∈CI} the objects that are R-related only to C’s (if to anything) ≥|≤|= nR.C cardinality restrictions {x ∈∆ | #{y∈CI | 〈x,y〉∈RI} ≥|≤|= n} the objects that are R-related to at least|at m ost|exactly n C’s R ∋ a value restriction {x ∈∆ | 〈x,aI〉∈RI} the objects that are R-related to a ∃R.Self reflexivity restriction {x ∈∆ | 〈x,x〉∈RI} the objects that are R-related to themselves {a} nominal {a I} a 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. Use ABox assertions whenever possible. 1. every student belongs to exactly one team, and every team is formed by three to five…