Z 39 50 XML RDF Applications ZIG Tutorial

Z 39. 50, XML & RDF Applications ZIG Tutorial January 2000 Poul Henrik Jørgensen, phj@dbc. dk Danish Bibliographic Centre, www. dbc. dk ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ

Contents n n Z 39. 50 Overview Z 39. 50 and XML Resource Description Framework, RDF Z 39. 50, XML and RDF Applications ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 2

Web Search Example ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 3

Z 39. 50 Overview n n n Z 39. 50 Targets (Z-Servers) supports a standard system interface to Z 39. 50 Origins (Z-Clients) Z-Clients support specialised user interfaces Z-Clients submit metadata Searches to Z-Servers returns pointers to relevant resources Z-Servers can return structured information according to requests from Z-Clients can access different Z-Servers – and vice versa ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 4

Z 39. 50 Search Example ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 5

XML Overview n n n HTML was intended to handle formatted text XML is designed by W 3 C to handle structured information Programs may access XML structures via the Document Object Model (DOM) Application Program Interface Related standards handle transformations (XSL) and searching of XML structures (XQL) XML may transform the Web from a large text archive to a large database of structured information ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 6

Z 39. 50 and XML n n Z 39. 50 handle XML as another transfer syntax like SUTRS, MARC or GRS-1 XML can do many of the same things as GRS-1 - and XML can be edited by hand Several Z 39. 50 Profiles use XML for Metadata, Item Orders, Electronic Document Delivery and Explain Info What about Holdings data? ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 7

Z 39. 50 XML Example ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 8

Resource Description Framework n n Describe relationships and attributes of (Internet) resources, i. e. advanced metadata Based on Directed Labelled Graphs (DLG) and classical Information Analysis May be represented by XML – but is basically independent of any representation format. Attributes and Relation types may be defined by XML Namespaces, e. g. Dublin Core ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 9

RDF Elements n n n An RDF Resource is an instance of one or more Classes Resources have Properties (=attributes) A Class may be a Subclass of another Class Properties are Values or Relations RDF Statements: Resource (Subject) + Property (Predicate) + Value (Object) ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 10

RDF Statement n n n The resource http: //doc 123 (Subject). has the Title (Property) ”Out of Africa” (Value) has the Creator (Property) ”Karen Blixen” (Value) ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 11

RDF Graph Example Creator Karen Blixen http: //doc 123 Title ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ Out of Africa 12

RDF, IFLA 4 LM and DC n n RDF can use any namespace for properties Several namespaces can be referenced in a given RDF structure Several Z 39. 50 Profiles use the RDF DC specification for cross-domain access DBC use RDF with IFLA Entity. Relationship Model (IFLA 4 LM) to navigate normative data ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 13

RDF Dublin Core Example <? xml version="1. 0"? > <rdf: RDF xmlns: rdf="http: //www. w 3. org/1999/02/22 -rdf-syntax-ns#" xmlns: dc="http: //purl. org/dc/elements/1. 0/"> <rdf: Description rdf: about="http: //www. ukoln. ac. uk/metadata/resources/dc/data model/ WD-dc-rdf/"> <dc: title> Guidance on expressing the Dublin Core within the Resource Description Framework (RDF) </dc: title> <dc: creator> Eric Miller </dc: creator> <dc: subject> Dublin Core; Resource Description Framework; RDF; e. Xtensible Markup Language; XML </dc: subject> <dc: format> text/html </dc: format> <dc: language> en </dc: language> </rdf: Description> </rdf: RDF> ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 14

RDF XML IFLA 4 LM Example ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 15

RDF Graph & IFLA 4 LM Screen-dumps from the Visual. Cat Client ©Portia I/S A Person object has several attributes incl. six names (i. e. synonyms), dates and a title. This Person is related to an object, with several attributes including Title (”Out of Africa”) Users can click on any object to see related objects as illustrated in the following slide. ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 16

RDF Graph Navigation The generic ”Out of Africa” object is expanded to show related works including three translations (some attribute names are in Danish) ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 17

Z 39. 50, XML and RDF Applications n n n Z 39. 50 can support XML as transfer syntax Z 39. 50 can support XQL search language Z 39. 50 can navigate RDF structures Z 39. 50 could support XML Namespaces Z 39. 50 could use HTTP - and possibly Simple Object Access Protocol (SOAP) ZIG 2000 -01 -19 Z 39. 50, XML & RDF / DBC-PHJ 18