1. 10-Sep-02 Page 1 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University10-Sep-02 Page 1 Gadjah Mada University - Yogyakarta - Indonesia Using DAML+OIL to Enrich RDF Schema for the Information Integration Ahmad Ashari IIWAS 2002 Bandung - Indonesia Sept 10 th -12 th 2002 Faculty of Mathematics and Natural Sciences

2. 10-Sep-02 Page 2 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Outline Information Integration Resource Description Framework (RDF) DAML+OIL RDF Schema vs DAML+OIL Conclusion and Future work

3. 10-Sep-02 Page 3 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Information Integration There are three type of information integration task: Technical Integration  already done with TCP/IP, HTTP, FTP, etc. Syntactic Integration  also already done with HTML Semantic Integration  Semantic Web in the future

4. 10-Sep-02 Page 4 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Integration Problem Too much unintegrated data: –from a variety of incompatible sources –no standard naming convention –each with a custom browsing and querying mechanism (no common interface) –and poor interaction with other data sources

5. 10-Sep-02 Page 5 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Data Sources Flat Files URLs Proprietary Databases Public Databases Spreadsheets Emails Etc.

6. 10-Sep-02 Page 6 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Outline Information Integration Resource Description Framework (RDF) DAML+OIL RDF Schema vs DAML+OIL Conclusion and Future work

7. 10-Sep-02 Page 7 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Resource Description Framework Resource Description Framework (RDF): (Syntactical) basis of the “semantic web” Similar to semi-structured data: graphs (RDF ~ OEM) Three basic object types: – resource s: all things being described; named by URIs – propertie s: attributes to describe a resource – statement s: subject + predicate + object; are all resources (object can also be a literal) Example: –“the creator of this home page is Ahmad Ashari ” subject: http://www.ifs.tuwien.ac.at/~ashari/ predicate: http://www.purl.org/dc/.../creator object: “Ahmad Ashari”

8. 10-Sep-02 Page 8 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Representation –Model as graph: –Serialized in XML syntax (“RDF/XML”): <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#” xmlns:dc="http://www.purl.org/dc/elements/1.0/"> Ahmad Ashari RDF Model and Syntax http://www.ifs.tuwien.ac.at/~ashari/ Ahmad Ashari dc:creator

9. 10-Sep-02 Page 9 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University RDF Schema RDF = simple data model RDF Schema allows definition of vocabularies for RDF data Simple frame system / ontology language: – classes, subclasses, properties, sub-properties, domain, range Extension of RDF in RDF

10. 10-Sep-02 Page 10 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University XML Name Space XML Name Space (XMLNS) are use for abbreviated a Universal Resource Identifier (URI) for example: –xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#“ for rdf, which point to RDF Model and Syntax Specification URI –xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#“ for rdfs, which point to RDF Schema Specification URI

11. 10-Sep-02 Page 11 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Outline Information Integration Resource Description Framework (RDF) DAML+OIL RDF Schema vs DAML+OIL Conclusion and Future work

12. 10-Sep-02 Page 12 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University DAML DAML or DARPA Agent Markup Language is a language created by DARPA as an ontology and inference language based upon RDF DAML takes RDF Schema a step further, by giving us more in depth properties and classes DAML allows one to be even more expressive than with RDF Schema, and brings us back on track with our Semantic Web discussion by providing some simple terms for creating inferences

13. 10-Sep-02 Page 13 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University DAML Language 2001-03: DAML+OIL (March 2001) 2000-12: DAML+OIL (December 2000) 2000-10: DAML-ONT 2000-08: DAML 0.5

14. 10-Sep-02 Page 14 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University DAML+OIL Bringing together DAML’s ontology language and OIL –OIL stand for Ontology Inference Layer or Ontology Interchange Language –Ontology is a formal, explicit specification of a shared conceptualization Keeps OIL’s mapping to Description Logic. –OIL support for Frame Based and Description Logic Use XML syntax and extension of RDF Support for concrete types (from XML Schema)

15. 10-Sep-02 Page 15 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Outline Information Integration Resource Description Framework (RDF) DAML+OIL RDF Schema vs DAML+OIL Conclusion and Future work

16. 10-Sep-02 Page 16 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University RDF Schema vs DAML+OIL Class definition for enumeration

17. 10-Sep-02 Page 17 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Class definition for a property

18. 10-Sep-02 Page 18 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Datatype Property

19. 10-Sep-02 Page 19 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Object Property

20. 10-Sep-02 Page 20 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Instances

21. 10-Sep-02 Page 21 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Unique Property Cardinality=1

22. 10-Sep-02 Page 22 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Inverse and Transitivity

23. 10-Sep-02 Page 23 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Broadening Classes

24. 10-Sep-02 Page 24 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Sub-class Person : (and Animal (all (restrict hasParent Person))

25. 10-Sep-02 Page 25 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Sub-class (2) 1 (atmost 1 father) (atleast 1 shoesize))

26. 10-Sep-02 Page 26 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Sub-clas (3)

27. 10-Sep-02 Page 27 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Complement Class

28. 10-Sep-02 Page 28 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Disjoint Class

29. 10-Sep-02 Page 29 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Equivalent Class

30. 10-Sep-02 Page 30 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Intersection Class

31. 10-Sep-02 Page 31 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Comparison Summary Feature RDFS DAML+OIL Syntax XML RDF Basic Datatypesonly one use XSDL type Enumeration of Property ValuesNo Yes Bounded ListsNo Yes Transitive PropertiesNo Yes NegationNo Yes Disjunctive / Disjoint No Yes Intersection No Yes

32. 10-Sep-02 Page 32 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Inference vs Information Integration The principle of “inference” is being able to derive new data from data that we already know Querying is a form of inference (being able to infer some search results from a mass of data, for example) Inference is one of the driving principles of Information Integration

33. 10-Sep-02 Page 33 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University RDF Schema Model rdf := 'http://www.w3.org/...rdf-syntax-ns#'. rdfs := 'http://www.w3.org/.../PR-rdf-schema-...#'. type := rdf:type. subPropertyOf := rdfs:subPropertyOf. subClassOf := rdfs:subClassOf. FORALL Mdl @rdfschema(Mdl) { transitive(subPropertyOf). transitive(subClassOf). FORALL O,P,V O[P->V] V]@Mdl. FORALL O,P,V O[P->V] P] AND O[S->V]). FORALL O,P,V O[P->V] W] AND W[P->V]). FORALL O,T O[type->T] T] AND O[type->S]). }

34. 10-Sep-02 Page 34 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University DAML+OIL daml := 'http://www.daml.org/.../daml+oil#'. animals := 'http://www.example.org/animals#'. @animals:ontology { animals:Animal[rdf:type -> daml:Class]. animals:Herbivore[rdf:type -> daml:Class; rdfs:subClassOf -> animals:Animal]. animals:Carnivore[rdf:type -> daml:Class; rdfs:subClassOf -> animals:Animal; daml:disjointWith -> animals:Herbivore]. animals:Omnivore[rdf:type -> daml:Class; rdfs:subClassOf -> animals:Herbivore; rdfs:subClassOf -> animals:Carnivore]. } FORALL Ont @check(Ont) { FORALL C unsatisfiable(C) <-C[ daml:subClassOf -> daml:Nothing]@daml_oil(Ont). }

35. 10-Sep-02 Page 35 Gadjah Mada University - Yogyakarta - Indonesia Gadjah Mada University Conclusion and Future Work DAML+OIL system can enrich RDF and RDFS, which is with this ontology based language we can eliminate the limitation of RDF Schema in describing the meaning of each information sources. In the previous work we already used RDF and RDF Schema for the Information Integration in tourism domain. DAML+OIL introduces many constructs and richer than RDF and RDFS, therefore in the future our works will use DAML+OIL for the Information Integration in the same or other domain.