1. INLS 150 Session 5 February 7, 2002 Cristina Pattuelli School of Information & Library Science UNC

2. Information Architecture An open architectural framework provides information access and aggregation or integration across diverse domains, including different communities, different types of information and different technologies.

3. FRBR 1998 IFLA, Functional Requirements for Bibliographic Records http://www.ifla.org/VII/s13/frbr/frbr.htm

4. Objectives of a Bibliographic System To find a document/entity that corresponds to user’s search criteria To identify an entity To select an entity that is appropriate to the user’s needs To acquire/obtain access to the entity described The Intellectual Foundation of Information Organization, Elaine Svenonius, 2000

7. Poul Henrik Jørgensen, Danish Bibliographic Centre, www.dbc.dk

8. Information Frameworks Kahn/Wilensky framework (K/W) Warwick Framework (WF) –Offer a conceptual foundation for an open architectural framework FEDORA begins to implement key concepts from K/W and WF IFLA FRBR W3C RDF

9. Khan/Wilensky Framework Developers  Robert Kahn Corporation for National Research Initiatives (CNRI)  Robert Wilensky University of California at Berkeley  Their research was supported by the Advanced Research Project Agency - May 1995

10. Kahn/Wilensky Framework Motivation To develop an infrastructure with open architecture for supporting a large and extensible class of distributed digital information services

11. Kahn/Wilensky Framework Architecture The System Digital Objects Handle, Handle generators Metadata, Key metadata Repositories - RAP Originators Users Global/Local naming authorities

12. Kahn/Wilensky Framework Key Components Digital Object = data + key-metadata Metadata includes the Handle = unique identifier of the Digital Object RAP (Repository Access Protocol)

13. FEDORA Flexible and Extensible Digital Object and Repository Architecture (FEDORA) Developed by Digital Library Research Group at Cornell University - A DARPA funded project http://www.cs.cornell.edu/cdlrg/fedora.html

14. Warwick Framework April 1996 - OCLC/UKOLN Warwick MetadataWorkshop (2 nd Dublin Core Metadata Workshop)

15. Warwick Framework 1.Need of architecture for the interchange of a wide variety of separately maintained metadata models 2. Need to insure extensibility of schemas

16. Warwick Framework Consensus was reached on: A high-level infrastructure for aggregating and interchanging multiple metadata packages associated with a common resource WF as the first practical approach to the effective integration of metadata into a global information infrastructure

17. Warwick Framework Architecture Containers Packages

18. Warwick Framework Architecture Container = unit for aggregating metadata packages –Transient –Persistent

19. Warwick Framework Architecture Packages types: –Metadata set –Indirect –Container itself

20. Warwick Framework Architecture  Container-package architecture Users or software agents able to aggregate discrete packages in a conceptual container No assumption about the content of the packages Containers and packages have identifiers for cross-reference on another

21. Warwick Framework Container

22. Warwick Framework Architecture Advantages:  Consistency in aggregating and exchanging metadata  Extensibility via modularity (LEGO metaphor) - vs. redundancy and overlapping - additional elements to support local or discipline-specific requirements

23. Extending DC (modularity) Modular extensibility… Additional elements to support local needs Complementary packages of metadata …but only if we get the building blocks right! DescriptionCMS record Terms & Conditions Based on a slide by Stu Weibel

24. Warwick Framework No constrains on means of communications –By email, file transfer, HTTP, etc. Implemented using MIME or SGML

25. RDF RDF is the core technology of the W3C’ Metadata Activity Provides a coherent umbrella framework suitable for use by the various metadata applications of W3C Has been highly influenced by Warwick Framework RDF embraces and extends the philosophy of WF to allow what has been called “fine grained’ metadata mixing

26. RDF –Resource Description Framework Model & Syntax –Recommendation of W3C, 1999 –Generic “architecture” for metadata set of conventions for applications exchanging metadata allow semantics to be defined by different resource description communities accommodate mixing of metadata from diverse sources XML and Educational Metadata, SBU, London, 10 July 2001

27. RDF –Defines model for making statements about resources conventions for encoding statements using XML syntax –Object types Resource : any object identified by URI –not necessarily accessible via Web Property : attribute to describe resource –properties also uniquely identified by URI Statement : triple of specific resource, named property, and value XML and Educational Metadata, SBU, London, 10 July 2001

28. The RDF Model XML and Educational Metadata, SBU, London, 10 July 2001 http:/my.domain/doc/ author Pete A resource has some property whose value is either (i) a simple string value (literal)…. The resource identified by the URI http://my.domain/doc/ has a property “author” whose value is “Pete” Or, “Pete” is the “author” of the resource identified by http://my.domain/doc/

29. The RDF Model (2) … or (ii) another resource http://my.domain/doc/ author Petepete@my.domain nameemail The value of property “author” is another resource which has a property “name” with value “Pete” and a property “email” with value “pete@my.domain” XML and Educational Metadata, SBU, London, 10 July 2001

30. The RDF XML Syntax – –XML representation of model store/exchange descriptions – –Property names made unique through use of XML namespaces. – –Variant syntaxes <rdf:Description about=”http://my.domain/doc/”> Pete XML and Educational Metadata, SBU, London, 10 July 2001

31. RDF Schema – –Resource Description Framework Schema – –Candidate Recommendation of W3C, 2000 – –Provides mechanisms to define vocabularies used in RDF statements e.g. Dublin Core metadata element set defined using RDF(S) XML and Educational Metadata, SBU, London, 10 July 2001

32. RDF Schema – –Defines type system resources grouped into classes classes related hierarchically (subClassOf) properties related hierarchically (subPropertyOf) use of properties constrained (domain, range) – –RDF Schema employs RDF model expressible using RDF/XML syntax

33. RDF, XML & Interoperability – –Why isn’t XML enough? simple statement could be expressed in XML in many different ways human reader makes interpretation/guess application program requires prior knowledge of schema/DTD design RDF imposes extra syntactic constraints on how statement expressed with RDF/XML, both human and program can interpret description consistently – –Less flexibility, greater interoperability XML and Educational Metadata, SBU, London, 10 July 2001

34. RDF, XML & Interoperability – –Use XML for exchange when applications both “know” semantics conveyed by structure of (meta)data – –Use RDF/XML for exchange when (meta)data potentially used by applications without prior “knowledge” of specific schema (meta)data incorporates overlapping structures from different domains XML and Educational Metadata, SBU, London, 10 July 2001

35. Memex = Memory Extension Vannevar Bush “A device where an individual stores all his books, records, and communications, and which is mechanized so that it may be consulted with exceeding speed and flexibility”

36. HyperText Hypertext is a text which contains links to other texts. The term was invented by Ted Nelson around 1965. From: http://www.cs.sfu.ca/CourseCentral/365/li/material/notes/Chap1/Chap1.html#HyperMulti

37. HyperText http://www.cs.sfu.ca/CourseCentral/365/li/material/notes/Chap1/Chap1.html#HyperMulti

38. Xanadu / Ted Nelson “Xanadu is the original hypertext and interactive multimedia system, under continuous development since 1960” “Docuverse”

39. The Road to Xanadu In Xanadu did Kubla Khan a stately pleasure-dome decree... Samuel Taylor Coleridge, "Kubla Khan”