The document proposes an approach called EvoPat for managing the evolution of RDF knowledge bases through the use of evolution patterns and describes a conceptual model and classification of patterns. It also discusses an implementation of EvoPat as an extension for the OntoWiki semantic wiki and an evaluation of its scalability using a test knowledge base. The approach allows for modular descriptions of common evolution patterns to facilitate agile knowledge engineering.

1. - EvoPat - Pattern-Based Evolution and Refactoring of RDF Knowledge Bases Christoph Rieß, Norman Heino, Sebastian Tramp and Sören Auer AKSW, Universität Leipzig

2. Content Motivation

3. Example

4. The EvoPat approach Concepts

5. Pattern Classification & Survey

6. Implementation & Evaluation Conclusion

7. Motivation Agile Knowledge Engineering By birgerking@flickr

8. Motivation Agile Knowledge Engineering

9. Steady process of Evolution in Knowledge Bases By petercat.harris@flickr

10. Motivation Agile Knowledge Engineering

11. Steady process of Evolution in Knowledge Bases

12. Can we manage this process? By MyMeltingBrain@flickr

13. Example Steve collects spiders from the caucasus region

14. He uses tags to describe special qualities (not covered by his schema) By pamilne@flickr http://db.caucasus-spiders.info

15. Example Some of his tags follow a special semantic (location descriptors, time descriptors, ...)

16. Now Steve wants to extend his vocabulary for these tags

17. That's evolution! By pamilne@flickr http://db.caucasus-spiders.info

18. Concepts (Excursion) Software Engineering Refactoring

19. Code Smells By helder@flickr

20. Concepts Basic Evolution Pattern Atomic evolution and refactoring operation

21. Works on data and schema level

22. Concepts Basic Evolution Pattern Atomic evolution and refactoring operation

23. Works on data and schema level Compound Evolution Pattern Linear sequence of several basic patterns

24. Concepts Basic Evolution Pattern Atomic evolution and refactoring operation

25. Works on data and schema level Compound Evolution Pattern Linear sequence of several basic patterns Bad Smell detects a suspicious structure in a knowledge base

26. Conceptual Model

27. Conceptual Model

28. Example “ Please set the language to X for all literals which do not have a language tag yet.” lang type : LANG s type : TEMP p type : TEMP ltrl type : TEMP SELECT DISTINCT * WHERE { %s% %p% %literal%. FILTER ( isLiteral(%literal%) ) FILTER ( lang(%literal%) = '' ) } INSERT: %s% %p% setLanguage(%literal%,%lang%) DELETE: %s% %p% %literal% V S U

29. Example Setup non-temp vars Materialize query Execute pre-processor functions

30. Execute query lang = en type : LANG s type : TEMP p type : TEMP ltrl type : TEMP SELECT DISTINCT ?s ?p ?ltrl WHERE { ?s ?p ?ltrl . FILTER ( isLiteral( ?ltrl ) ) FILTER ( lang( ?ltrl ) = '' ) } INSERT: %s% %p% setLanguage(%literal%,%lang%) DELETE: %s% %p% %literal% V S U

31. Example 3) For each result row: Materialize update queries

32. Execute pre-processor functions

33. Execute queries lang = en type : LANG s type : TEMP p type : TEMP ltrl type : TEMP SELECT DISTINCT ?s ?p ?ltrl WHERE { ?s ?p ?ltrl . FILTER ( isLiteral( ?ltrl ) ) FILTER ( lang( ?ltrl ) = '' ) } INSERT: %s% %p% setLanguage(%literal%,%lang%) (e.g.: foaf:Person rdfs:label 'person'@en ) DELETE: %s% %p% %literal% (e.g.: foaf:Person rdfs:label 'person' ) V S U