Outline

1. Stephan KörnigAli MahdouiJulia StollRudi SchmiedeA Generic Framework for the Exchange and Usage of Semantically Enriched Information Project of the Darmstadt University of Technology within the competence network „New Services, Standardization, Metadata“ (bmb+f)

2. Outline • Motivation / Goals of the Project • Web Services • Digital Library Services for Scientists • Applications • Cooperation / Clearinghouse NKOS Workshop, Trondheim 2003

3. Motivation Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Known problems for integration • Distribution of information / Heterogeneity • Development technology-driven / short cycles of innovation • “Web Services” (W3C) as a promising standard • Framework for scientific use of information is missing NKOS Workshop, Trondheim 2003

4. Standards Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Standardization as a part of the problem • Standardization is research • Standardization of own developments gives return on investment • Standards: high/low level of details • Missing specs for Digital Library-Services • Background „dl-konzepte“: concepts for the improvement of scholarly information systems • Domain specific solutions required NKOS Workshop, Trondheim 2003

5. Requirements Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Scope: scholarly information within scientific net(work)s • (Technical & organizational) support of distributed systems • Light-weight technology • Support of dynamic changes • Support of a (domain specific) view on resources NKOS Workshop, Trondheim 2003

6. Goals Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Specification of DL-Services • Generic Framework supporting the implementation of scientific • portals • peer2peer networks • workspaces • Organizational issues NKOS Workshop, Trondheim 2003

7. Web Services - Basics Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Again: this is about the W3C standard • Remote procedure calls via HTTP • Supports interaction of distributed, loose coupled and reusable software components • Integration of legacy systems / middle-ware for heterogeneous networks • Openness: Machine readable description available (WSDL) – accessible via public (UDDI-) Registries NKOS Workshop, Trondheim 2003

8. Provision of Web Services Discovery Agency (UDDI) Service- Descriptions (WSDL) find publish Service Provider Service Requestor interact

9. Existing web services WSDL- descriptions OAI based document harvester Newsservice Scientific database XML/SOAP XML/SOAP XML/SOAP UDDI- Registry Network- node 1 Network- node 2 XML/SOAP XML/SOAP XML/SOAP Network- node n Scenario: Web Services based Infrastructure for Digital Libraries

10. WSDL – Limitations of the Standard Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Still undergoing changes • Tries to support different paradigms • Object orientation • Functional programming • (Relational) database access • Some transformations will need support by specialized wrappers NKOS Workshop, Trondheim 2003

11. DL-Services for Scientists Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Services: logical view • Generalization of Access and Formats • Type system / Ontologies NKOS Workshop, Trondheim 2003

12. Service (user‘s perspective) Metamodel Types of services Types of material Functionality model and implementation Service Provision (Web-Service) DL-Services (logical view) Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse NKOS Workshop, Trondheim 2003

13. Standardization of access Standardization of formats/protocols Types of services and material Interface specifications WSDL descriptions Metamodel of the framework Access and Formats Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse Task with different level of generalization NKOS Workshop, Trondheim 2003

14. KOS related DL- Services Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Services allowing access to thesauri / ontologies or concepts (eg Query expansion) • More use cases? • Problem in the context of our framework: Modeling with RDFS/OWL does not integrate into XML NKOS Workshop, Trondheim 2003

15. XML-Repository WSDL-Service Support Service <<facade>> Generator Dispatcher Service- Localization Framework (logical view) Metamodel of Services Data processed by Services Webserver (Cocoon2) Service creation and assembly Support Services Transaction- management Java-classes (framework application)

16. Framework (instantiation)

17. Development Activities Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Utilizing upcoming standards or specifications (e.g. JXTA) • Ability to support the different types of use cases (portal, P2P, workspace) • Focus on application supporting the maintenance of content within a scientific portal for science nets NKOS Workshop, Trondheim 2003

18. Cooperation/Clearinghouse Motivation / Goals of the Project Web Services Digital Library Services for Scientists Applications Cooperation / Clearinghouse • Importance of people behind standardization effort • Cooperation on a national level (network of competence) • Utilizing international accepted standards • Open for cooperation NKOS Workshop, Trondheim 2003