TU Wien:Einführung in Semantic Systems VU (Tjoa)/Exam 2020-01-28

General

This was the first exam for the new course. The organizers forgot make a registration for the exam in TISS, and opened the registration a few days before. The exam was held from 8am (sharp) to 10am, although most were finished within about 45 minutes. There were 6 single-choice questions worth 3 points each and 6 open questions worth 5 points each. In total, there were 50 points for the exam, with 2 extra points for a more elaborate answer in one of the open questions. The organizers released a question pool in TUWEL a week before the exam as a study reference. In the exam, the open questions were *exactly* as in the question pool.

Group B

6 Single choice questions, 3-4 possible answers. Worth 3 points each.

(very roughly from my memory)

• What statement about KGs is true?
• Something about SPARQL queries, the answer was that ASK returns a boolean value
• Something about Semantic Web Technology stack?
• Which relationship describes "Austria is neighbor of Italy" -> Symmetry
• What description fits RDF triple best -> predicate states relationship between subject and object [they had this question worded wrong, had predicate where object should have been]
• Something about what we can do/not do with RDF-S

6 open questions, each worth 5 points

(Worded as in the question pool, here only short versions given)

1. Define ontology, use definition by Studer (1998)
2. What are the main stages of ontology engineering
3. What does the notion of Reification mean?
4. Define the term semantic annotation
5. What is the typical structure of a SPARQL query?
6. What are the conceptual differences between RDF4J Apache Jena?

Group A

Single choice

• Four definitions of ontologies, one is correct
  • Answer: Ontologies are used in computer science in order to enable computers to process domain knowledge
• Which kind of property is used to describe that Vienna is part of Europe in: Austria is part of Europe, Vienna is part of Europe?
  • Answer: Transitive property
• ?
• Four statements about SPARQL.
  • Answer: SELECT matches a subgraph
• ?
• Four statements about RDF-S, one is correct.

Open

• Provide two of the definitions of a knowledge graph discussed during the lecture.
• Which are the three main categories of ontologies based on their expressivity? Give examples for each category.
• What are three types of reasoning tasks that can be performed on ontologies? Bonus points: provide example for each reasoning task.
• Describe the process of transforming a database into an RDF dataset by using R2RML. Additionally, describe the mandatory and optional components of an R2RML mapping definition.
• For two RDF entailment patterns of your choice (1) describe the pattern and (2) exemplify how querying is affected when reasoning in terms of that pattern in comparison to the case when no reasoning is enabled.
• Describe at least two architectural patterns for KG applications.