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e Learning and S emantic Web. AIFB. Rudi Studer Christoph Schmitz, Steffen Staab, Gerd Stumme, Julien Tane Learning Lab Lower Saxony http://www. learninglab.de Institute AIFB, University of Karlsruhe http://www.aifb.uni-karlsruhe.de/WBS. Overview. Motivation
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eLearning and Semantic Web AIFB Rudi Studer Christoph Schmitz, Steffen Staab, Gerd Stumme, Julien Tane Learning Lab Lower Saxony http://www.learninglab.de Institute AIFB, University of Karlsruhe http://www.aifb.uni-karlsruhe.de/WBS
Overview • Motivation • Semantic Web: Ontologies and Metadata • Ontology-based eLearning • Conclusion
Motivation eLearning aims at replacing • time • place • content predetermined learning with a • task-relevant • personalized • just-in-time • active process of learning How do we achieve these objectives?
Metadata eLearning Standards Goal: To promote and facilitate the discovery, retrieval,andcomposition of relevant eLearning materials Approach: • Provide descriptions of learning resources • Enable search and query • Enable configuration of learning components
Current Metadata Standards for eLearning • IEEE LOM(Learning Object Meta-data) • ARIADNE – Alliance of Remote Instructional, Authoring and Distribution Networks for Europe • IMS – Instructional Management System Global Learning Consortium
Characteristics of Current Approaches <Classification> <Taxonpath> <Taxon> <Entry>Engineering</entry> <Taxon> <Entry> Electr. Engineering</entry> <Taxon> <Entry> <langstring xml:lang="en"> Integrated Digital Circuit </langstring> </Entry> </Taxon> </Taxon> </Taxon> </Taxonpath> </Classification> <SemanticsOfTheResource> <Discipline> Engineering </Discipline> <Subdiscipline> Electr. Engineering <Subdiscipline> <MainConcept> Integrated Digital Circuit </MainConcept> <MainConcept> Chip </MainConcept> <OtherConcepts> CMOS </OtherConcepts> </SemanticsOfTheResource> Challenges: • Name Conflicts • Structure Conflicts • Limited Semantics
Limitations of current Web-based solutions • search and query is restricted to keyword-based methods • contents of course components is captured only partially • lack of flexible customization to user needs • lack of flexible configuration of course components
Overview • Motivation • Semantic Web: Ontologies and Metadata • Ontology-based eLearning • Conclusion
Semantic Web “The Semantic Web: a new form of Web content that is meaningful to computers will unleash a revolution of new possibilities“ (Tim Berners-Lee et al., Scientific American, 2001) • Make content accessible and interpretable by machines • Provide metadata that come with precisely defined semantics • Provide shared vocabulary
Meaning Triangle Concept evokes refers to Thing Symbol stands for “People [and machines] can’t share knowledge if they don’t speak a common language” (Davenport) jaguar
Ontologies “An ontology is an explicit specification of a conceptualization“ (Gruber 1993) Ontologies offer • a conceptual foundation for communicationbetween actors • aformal basis to define a vocabulary • a vocabulary that is shared among a group of actors Ontologies are used at run time, they are part of the eLearning application
Ontologies and RDF/RDFSchema • RDF/RDFSchema provide modelling primitives for lightweight ontologies • classes and subClass hierarchies • properties and subProperty hierarchies • domain and range specifications for properties • instances
Ontologies & RDF(S) rdfs:Resource rdfs:Class rdf:Property appl:Topic appl:Title appl:Document appl:content appl:Protocol appl:Service Subject http://www.fzi.de/WIM/Protocol.html Predicate Object HTTP Protocol RDF/RDFS layer and namespace subClassOf instanceOf application specific schema and namespace appl:content application specificactual data appl:Title „RFC2068: Hypertext transfer Protocol“
Semantic Web & Ontologies • More heavyweight ontologies all to capture more semantics of a domain • prevDocument and nextDocument are inverseto each other • subClassOf is transitive • axiomsyield additional knowledge: teaches (prof1, course2) and isAbout (course2, ontologies) knowsAbout (prof1, ontologies)
Overview • Motivation • Semantic Web: Ontologies and Metadata • Ontology-based eLearning • Conclusion
Semantic Web & eLearning • The Semantic Web is a very suitable framework for realizing some aspects of eLearning systems • Development steps: • collaborative ontology developmentfor eLearning • ontology-based annotation of learning material • integration of learning resources • dynamiccomposition of course material • Access: • proactive delivery of the learning materials • integrated browsing and query facilities
Conventional Metadata for eLearning <Classification> <Taxonpath> <Taxon> <Entry> Engineering </entry> <Taxon> <Entry> Electr. Engineering</entry> <Taxon> <Entry> <langstring xml:lang="en"> Integrated Digital Circuit </langstring> </Entry> </Taxon> </Taxon> </Taxon> </Taxonpath> </Classification> <SemanticsOfTheResource> <Discipline> Engineering </Discipline> <Subdiscipline> Electr. Engineering <Subdiscipline> <MainConcept> Integrated Digital Circuit </MainConcept> <MainConcept> Chip </MainConcept> <OtherConcepts> CMOS </OtherConcepts> </SemanticsOfTheResource> Problems: • Lack offormal semantics • Different vocabulariesfor metadata • Lack of semantic mapping • Ontologiesare suitable as aconceptual backbone • Define shared understanding • Provide semantic underpinning for metadata
Ontology-based Metadata Metadata in eLearning are concerned with severalorthogonal dimensions: What the learning material is about (content) What is the learning situation (context) How is the learning material connected to other learning materials (structure) Context Learning resource Structure Content
Ontology-based Metadata Benefits in the process of providing and accessing information: Synonyms “Agent” and “Actor” Different languages “Lecture” (English) and “Vorlesung”(German) Morphological variations “eLearning”and “e-Learning” Semantic relationships “Computer Science” is a superTopicOf“Database Systems” „Professor“ is related to „Course“ via the teaches relation „CS101“ is an instanceOf „Course“
Overview • Motivation • Semantic Web: Ontologies and Metadata • Ontology-based eLearning • Conclusion
Conclusion Ontologies can support eLearning in three ways: • for describing the semantic content of the learning materials, • for defining the learning context and • for describing the structure of the learning materials
Conclusion This three-dimensional, semantically structured space enables • semanticquerying • PADLR module EdutellaPresentations byChristoph Schmitz and others • semanticnavigation • PADLR module Courseware WatchdogPresentation by Julien Tane • flexible combination and personalization of learning resources
Thank you! AIFB Learning Lab Lower Saxony http://www.learninglab.de Institute AIFB, University of Karlsruhe http://www.aifb.uni-karlsruhe.de/WBS