OWL

Reading:

• Ontology, SW languages
• Web Ontology Language: OWL
• Lecture on Web Ontology Language OWL
• OWL tutorial

• Build your first ontology

• what is Ontology?
• what is an ontology?
• what are the ontologies for?
• what are the main components of an ontology?

• what is OWL and what sublanguages the are?
• what RDFS limitations does OWL overcome?
• Based on Lecture on Web Ontology Language OWL list the differences between RDFS and OWL

• what are Description Logics?
• What are the consequences of OWL being grouned in DL?
• What is Closed World Assumption, what Open World Assumption? Which is valid in OWL?

• what are the reasoning tasks for a DL ontology?

• We will use Protégé, an ontology editor, version 3.4.4./4.1.alpha.
• We will learn OWL characteristics on the Pizza ontology example.
• Download the pizza menu and pizza toppings cards. Think how to group pizza toppings (ingredients) into categories (e.g MeatTopping, CheeseTopping, VegetableTopping etc.) ( PDFs! descriptions in examples do not match protege menus!)
• You are supposed to make the instructions with assistance of Protege OWL tutorial.

While doing the exercise, make sure you understand:

1. Components of OWL ontology:
   • individuals
   • properties
   • classes
2. Classes: basic building blocks
   • Named Class
   • Intersection classes
   • Union classes
   • Complement classes
   • Restrictions
     • Universal restrictions
     • Existential restrictions
   • Enumerated classes
3. Reasoning services:
   • Subsumption testing
   • Equivalence testing
   • Consistency testing
   • Instantiation testing

• Run Protégé: Log in to charon, open terminal and type

protege3

• For a reasoner choose direct connection with Pellet (Reasoning > Pellet 1.5.2.(direct))
• Go through the exercises in University of Manchester tutorial

• Design an OWL ontology in Protege. It can be a domain ontology (e.g. University) or a task ontology( e.g. Travelling)
  • use various OWL DL constructs (see Piza example)
  • check the ontology consistency
  • infer new instances

Materials:

• Build your first ontology
• Protege documentation

Additional resources:

• http://www.co-ode.org/ontologies/
• http://owl.cs.manchester.ac.uk/tutorials/protegeowltutorial/

Further reading:

• http://www.co-ode.org/resources/tutorials/
• SemWeb for the XML people
• OWL Tutorial from 2003
• Ontology Design patterns

Z braku lepszego miejsca tutaj studenci wpisują komentarze natury ogólnej do tego lab.