RDF Survey
This page gives a survey of information available for the Resource Description Framework (RDF). The survey is far away to be complete. If you want to contribute to this page, don't hesitate to contact Reinhold Klapsing. Currently I am working on a project to prove suitability of RDF for modeling web based information systems (XWMF).
Short Introduction to RDF
(taken out of the RDF Model and Syntax Specification) The World Wide Web was originally built for human consumption, and although everything on it is machine-readable, this data is not machine-understandable. It is very hard to automate anything on the Web, and because of the volume of information the Web contains, it is not possible to manage it manually. The solution proposed here is to use metadata to describe the data contained on the Web. Metadata is "data about data" (for example, a library catalog is metadata, since it describes publications) or specifically in the context of this specification "data describing Web resources". The distinction between "data" and "metadata" is not an absolute one; it is a distinction created primarily by a particular application, and many times the same resource will be interpreted in both ways simultaneously.

Resource Description Framework (RDF) is a foundation for processing metadata; it provides interoperability between applications that exchange machine-understandable information on the Web. RDF emphasizes facilities to enable automated processing of Web resources. RDF can be used in a variety of application areas; for example: in resource discovery to provide better search engine capabilities, in cataloging for describing the content and content relationships available at a particular Web site, page, or digital library, by intelligent software agents to facilitate knowledge sharing and exchange, in content rating, in describing collections of pages that represent a single logical "document", for describing intellectual property rights of Web pages, and for expressing the privacy preferences of a user as well as the privacy policies of a Web site. RDF with digital signatures will be key to building the "Web of Trust" for electronic commerce, collaboration, and other applications.

The specifications founding the RDF are:
History
Mailinglists
Further stuff from W3C related/relevant to RDF
Introductions, Overviews, Talks
Specifications related/relevant to RDF
  • History: While RDF started as an extension of the PICS content description technology, it also draws upon the XML design as well as technology submissions by Microsoft (XML Web Collections) and Netscape (XML/MCF). Other documents, such as Microsoft's XML-Data paper, Site Map proposals, and the Dublin Core/Warwick Framework have also influenced the RDF design.(See OCLC's Nov'97 Press Release.) (extracted from FAQs for RDF)
  • Web Architecture: Describing and Exchanging Data, W3C Note, 7 June 1999
    Authors: Tim Berners-Lee, W3C; Dan Connolly, W3C; Ralph R. Swick , W3C
    The World Wide Web is a universal information space. As a medium for human exchange, it is becoming mature, but we are just beginning to build a space where automated agents can contribute--just beginning to build the Semantic Web. The RDF Schema design [ RDFSchema] and XML Schema design [XMLSchema] began independently, but we explore a common model where they fit together as interlocking pieces of the semantic web technology.
  • PICSLabel Distribution Label Syntax and Communication Protocols- Version 1.1; W3C Recommendation, 31-October-96
    Authors: Tim Krauskopf, Spyglass; Jim Miller, W3C; Paul Resnick, AT&T?; Win Treese; OpenMarket
    This document has been prepared for the technical subcommittee of PICS (Platform for Internet Content Selection). It defines a general format for labels and three methods by which these labels may be transmitted: In an HTML document. With a document transported via a protocol that uses RFC-822 headers. Separately from the document
  • Web Collections using XML, Note, 09 March 1997
    Editor: Alex Hopmann et.al, Microsoft
    Web Collections are an application of XML [1] that is used to describe the properties of some object. Web Collections use XML to provide a hierarchical structure for this data. Each collection specifies that it uses a profile that allows applications to expect specific properties in that collection. For example a collection describing a web page might use the "WebPage" profile which would allow a program to know that this collection describes a web page and has properties such as author, last modified, etc.
    Submission request to W3C
  • Meta Content Framework Using XML, Note, 6 June 97
    Editors: R.V. Guha, Netscape Communications; Tim Bray, Textuality;
    This document provides the specification for a data model for describing information organization structures (metadata) for collections of networked information. It also provides a syntax for the representation of instances of this data model using XML, the Extensible Markup Language.
    Submission request to W3C
  • XML-Data, W3C Note, 05 Jan 1998
    Authors: Andrew Layman, Microsoft Corporation; Edward Jung, Microsoft Corporation; Eve Maler, ArborText; Henry S. Thompson, University of Edinburgh; Jean Paoli, Microsoft Corporation; John Tigue, DataChannel; Norbert H. Mikula, DataChannel; Steve De Rose, Inso Corporation
    Schemas define the characteristics of classes of objects. This paper describes an XML vocabulary for schemas, that is, for defining and documenting object classes. It can be used for classes which as strictly syntactic (for example, XML) or those which indicate concepts and relations among concepts (as used in relational databases, KR graphs and RDF). The former are called "syntactic schemas;" the latter "conceptual schemas."
    Submission request to W3C
  • XML Schema Part 1: Structures, W3C Working Draft, 6-May-1999
    Editors: David Beech, Oracle; Scott Lawrence (Agranat Systems); Murray Maloney (Commerce One); Noah Mendelsohn (Lotus); Henry S. Thompson, University of Edinburgh
    XML Schema: Structures is part one of a two part draft of the specification for the XML Schema definition language. This document proposes facilities for describing the structure and constraining the contents of XML 1.0 documents. The schema language, which is itself represented in XML 1.0, provides a superset of the capabilities found in XML 1.0 document type definitions (DTDs.)
  • XML Schema Part 2: Datatypes, W3C Working Draft, 06-May-1999
    Editors: Paul V. Biron, Kaiser Permanente for Health Level Seven; Ashok Malhotra, IBM
    This document specifies a language for defining datatypes to be used in XML Schemas and, possibly, elsewhere.
  • XHTML[tm] 1.0: The Extensible HyperText Markup Language A Reformulation of HTML 4.0 in XML 1.0. (the W3C Working Draft of 5th December 1998 explicitly mentioned RDF as basis for document profiles)
    Tim Berners-Lee, Director, W3C and Ralph R. Swick, Metadata Activity propose in an announcement that CC/PP can use RDF to produce machine-understandable descriptions of useful parts of their specifications.
  • Platform for Privacy Preferences (P3P) Syntax Specification; W3C Working Draft; 7 April 1999
    Editor: Massimo Marchiori, W3C,
    The Platform for Privacy Preferences Project (P3P) enables Web sites to express their privacy practices and enables users to exercise preferences over those practices. P3P compliant products will allow users to be informed of site practices (in both machine and human readable formats), to delegate decisions to their computer when appropriate, and to tailor their relationship to specific sites. Site practices that are compatible with a user's preferences can, at the user's option, be accessed "seamlessly". Otherwise users will be notified of a site's practices and have the opportunity to agree to those terms or other terms and continue browsing if they wish.
    P3P gives users the ability to make informed decisions regarding their Web experience and the ability to control the use of their information. Sites can use P3P to increase the level of confidence users place in their services, as well as improve the quality of the services offered, customize content, and simplify site access.
    P3P uses [XML] (using the [RDF] data model) for the exchange of structured data and assertions. P3P will support future digital certificate and digital signature capabilities. P3P can be incorporated into browsers, browser plug-ins, servers, or proxy servers that sit between a client and server.
    Tim Berners-Lee, Director, W3C and Ralph R. Swick, Metadata Activity propose in an announcement that P3P can use RDF to produce machine-understandable descriptions of useful parts of their specifications.
  • XML (W3C Recommendation 10-February-1998 )
  • XML namespaces(W3C Recommendation 14-January-1999) XML namespaces provide a simple method for qualifying element and attribute names used in Extensible Markup Language documents by associating them with namespaces identified by URI references.
  • XML Schema Requirements
  • DDML Document Definition Markup Language (DDML) Specification, Version 1.0. This document proposes Document Definition Markup Language (DDML), a schema language for XML documents. DDML encodes the logical (as opposed to physical) content of DTDs in an XML document. This allows schema information to be explored and used with widely available XML tools. ... DDML has been influenced by the XML-Data proposal [XML-Data]. It is hoped that DDML may be mapped to an RDF vocabulary.
  • DDML/XSchema The W3C has accepted XSchema, now retitled Document Definition Markup Language (DDML), as a submission.
  • DCD Document Content Description for XML. This document proposes a structural schema facility, Document Content Description (DCD), for specifying rules covering the structure and content of XML documents. The DCD proposal incorporates a subset of the XML-Data Submission [XML-Data] and expresses it in a way which is consistent with the ongoing W3C RDF (Resource Description Framework) [RDF] effort; in particular, DCD is an RDF vocabulary. DCD is intended to define document constraints in an XML syntax; these constraints may be used in the same fashion as traditional XML DTDs. DCD also provides additional properties, such as basic datatypes.
  • Schema for Object-oriented XML This document proposes a schema facility, Schema for Object-oriented XML (SOX), for defining the structure, content and semantics of XML documents to enable XML validation and higher levels of automated content checking. The SOX proposal is informed by the XML 1.0 [XML] specification as well as the XML-Data submission [XML-Data], the Document Content Description submission [DCD] and the EXPRESS language reference manual [ISO-10303-11]. SOX provides an alternative to XML DTDs for modeling markup relationships to enable more efficient software development processes for distributed applications. SOX also provides basic intrinsic datatypes, an extensible datatyping mechanism, content model and attribute interface inheritance, a powerful namespace mechanism, and embedded documentation. As compared to XML DTDs, SOX dramatically decreases the complexity of supporting interoperation among heterogenous applications by facilitating software mapping of XML data structures, expressing domain abstractions and common relationships directly and explicitly, enabling reuse at the document design and the application programming levels, and supporting the generation of common application components
  • A Discussion of the Relationship Between RDF-Schema and UML This note summarizes the relationship between RDF-Schema and UML, the generic industry standard object-oriented modeling framework for information systems modeling.
  • Universal Commerce Language and Protocol (UCLP), Version 3.0, W3C Note, 20-Jan-1999, Author/Organisation: SAIC/Bellcore
    The Universal Commerce Language and Protocol (UCLP) is an XML-compliant schema for tagging metadata that can be used in identifying and retrieving data residing across the Internet. The tags provide a base level of data typing while allowing industry-specific names to be defined as necessary to describe those properties and attributes which a user needs when discriminating among available choices. The introduction of data typing has been discussed as a needed extension to the XML 1.0 Recommendation, but UCLP is intended to introduce a new paradigm for dynamic data tagging for which data typing is only a required tool.
    Tim Berners-Lee, Director, W3C and Ralph R. Swick, Metadata Activity propose in an announcement that UCLP can use RDF to produce machine-understandable descriptions of useful parts of their specifications.
  • Personalized Information Description Language (PIDL), W3C Note, 09 Feb 1999
    Authors: Yuichi Koike, NEC; Tomonari Kamba, NEC; Marc Langheinrich, NEC
    This document describes an XML syntax for the Personalized Information Description Language (PIDL). The purpose of PIDL is to facilitate personalization of online information by providing enhanced interoperability between personalization applications. PIDL provides a common framework for applications to progressively process original contents and append personalized versions in a compact format. PIDL supports the personalization of different media (e.g. plain text, structured text, graphics, etc), multiple personalization methods (such as filtering, sorting, replacing, etc) and different delivery methods (for example SMTP, HTTP, IP-multicasting, etc).
    Tim Berners-Lee, Director, W3C and Ralph R. Swick, Metadata Activity propose in an announcement that PIDL can use RDF to produce machine-understandable descriptions of useful parts of their specifications.
  • XML Linking Language (XLink) W3C Working Draft 20-December-1999
    Authors: Steve DeRose, Eve Maler, David Orchard, Ben Trafford
    This specification defines the XML Linking Language (XLink), which allows elements to be inserted into XML documents in order to create and describe links between resources. It uses XML syntax to create structures that can describe the simple unidirectional hyperlinks of today's HTML as well as more sophisticated links.
    See appendix C; there are examples of how to map XLink to Resource Description Framework.
Implementations
  • RDF Schema Explorer This program reads RDF/XML documents into the 3-tuples of the corresponding RDF data model. You can feed some RDF stuff into the Explorer (either by keying it directly into the text field below or by uploading a file). This will be parsed with Jan's parser and the resulting triples will be asserted to the fact base. Then, you can VALIDATE your model against the rule set provided in version 1.2 of the paper "A logical interpretation of RDF". Furthermore, you can QUERY the model by using the already provided rule/fact set of Wolfram/Reinhold or by providing your own rules. But there is even more: you can DEFINE semantics for your own predicates directly within your RDF document -- example.
  • SiRPAC This program compiles RDF/XML documents into the 3-tuples of the corresponding RDF data model. The documents can reside on local file system or at a URI on the Web. Also, the parser can be configured to automatically fetch corresponding RDF schemas from the declared namespaces.
  • W3C RDF browsing interfaceYou can enter/paste here a new RDF entry and send it to the server. The server will produce you the triples of the corresponding data model and provide a visual browsing tool within the data model.
  • rpmfind client tool - Basically, rpmfind is a program that will find RPM files on rufus for you. Rpmfind can also be used to query the RPM database for existing packages using a keyword or a regular expression.
  • rpm2html : a generator of Web pages for RPM packages. rpm2html automatically generate Web pages describing a set of RPM packages. Rpm2html now support RDF encoding and decoding of RPM metadata. The long term goal is to provide metadata information for RPM packages on a large scale and use them to automate searching, installing and upgrade linux packages.
  • Index of /linux/RDF(Tool for managing Linux-RPM files)
Misc
  • A DTD for RDF M&S A transcription of the grammar in Resource Description Framework (RDF) Model and Syntax (by Ora Lassila and Ralph R. Swick, Version 0.2, 01-Oct-1997)
  • Example of an instanceTranscription of examples from Resource Description Framework (RDF) Model and Syntax (by Ora Lassila and Ralph R. Swick, Version 0.2, 01-Oct-1997)
Further Introductions/Talks/Presentations
Applications
  • XWMFAn eXtensible Web Modeling Framework - uses RDF to describe a web site
  • WebResourceMap: a simple website mapping RDF sample WebResourceMap is an application of RDF used to provide a simple mapping for one or more web sites. A WebResourceMap can describe metadata about the current state and changes in documents on a web site.
  • My Netscape Network Netscape have a metadata harvester of sorts which collects RDF Site Summary (their lightweight channel vocabulary) from known points on the Web. This is powering the next version of the my.netscape.com site.
  • The DESIRE Project The project's focus is on enhancing existing European information networks for research users across Europe through research and development in three main areas of activity: Caching, Resource Discovery and Directory Services.
  • GCS Grand Central Station (search engine from IBM using RDF internally to represent gathered data)
  • HotMETA A metadata repository currently indexes (gathers) abbreviated RDF
  • Reggie the Metadata Editor. The aim of the Reggie Metadata Editor is to enable the easy creation of various forms of metadata with the one flexible program. As it stands, the Reggie applet can create metadata using the HTML 3.2 standard, the HTML 4.0 standard, the RDF (Resource Description Framework) format and the RDF Abbreviated format.
  • http://www.dstc.edu.au/RDU/RDF/draft-iannella-vcard-rdf-00.txt This memo specifies a Resource Description Format (RDF) [RDF] encoding that corresponds to the vCard electronic business card profile defined by RFC 2425 [VCARD]. This specification provides equivalent functionality to the standard format defined by [VCARD]
  • Basic installation of SiLRI SiLRI is a simple deductive database implemented in Java that is able to reason with metadata in the XML serialization of RDF (Resource Description Format). SiLRI was developed in the context of the Ontobroker-project.
  • RDF in Java This processor provides facilities for building RDF structures, navigating and querying them, manipulating them, and converting them to their equivalent XML forms. It also has facilities to perform I/O operations on RDF structures.
  • RDF for XML : another alphaWorks technologyRDF for XML is an RDF processor written in Java for building, querying, and manipulating RDF structures and reading and writing them in XML forms. The current implementation conforms to the working draft dated 02/16/98 of the RDF Syntax and Model working group of the W3C.
  • Using XML in Knowledge Management prototype provides a front-end for researchers within the organization to search multiple online sources, view clustered search results and finally produce a finished document summarizing the requested information. ... are currently working on a process to generate this meta-information in an XML-based format (such as RDF or MCF).
Paper/Conferences
  • Three papers on Web Query Languages, RDF etc form the W3C Query meeting (Dan Brickley)
  • A Query and Inference Service for RDF The creation of RDF raises the prospect of a widely accepted standard for representing expressive declarative knowledge on the Web. However, just representing knowledge and information is not enough: users as well as information agents have to query and use the data in several ways. An RDF Query specification would allow a range of applications to exploit any information source which can be represented in terms of the RDF data model. (Stefan Decker, Dan Brickley, Janne Saarela, Jürgen Angele)
  • Position Paper A Description of MMB Concepts in RDF and Metadata Model Conversion to RDF (William W. Song)
  • Workshop MetaData Qualifying WebObjects
  • Metastructures 1998 & XML Developers' Conference - www.gca.org
  • Proceedings of the First IEEE Metadata Conference, April 16-18, 1996. Topics:
    • Metadata Usage
    • Metadata Modeling
    • Data Mining for metadata extraction
    • Metadata Standards
    • Metadata for System Integration
    • Data Stewardship
    • Metadata issues related to the EOSDIS program
    • Ontologies
    • Common Metadata models for metadata
  • Proceedings of the Second IEEE Metadata Conference, September 16-17, 1997. Topics:
    • Metadata for:
      • Management & modeling
      • Semantic representation of the WWW
      • Mass storage and warehousing
    • Metadata mining & extraction
    • Metadata catalogs
    • Systems for managing metadata
    • Application-specific metadata
    • Digital library metadata issues
    • Standards, Working systems
Organisations
DSTC
  • The DSTC is a joint venture supported by the Australian Government's Cooperative Research Centres Program and over 24 participating organisations developing the technical infrastructure for tomorrow's enterprise.
  • The Resource Discovery Unit (RDU) is a project from the Research Data Network CRC and is operated by the DSTC.
  • General information about RDF projects of DSTC
  • RDF Schema Functional Requirements, RDF Working Group, 13 March 1998
  • An Idiot's Guide to the Resource Description Framework (Renato Iannella)
  • Metadata Repositories and Registries using RDF, Renato Iannella at First European Conference on Research and Advanced Technology for Digital Libraries, Pisa, Italy, September 1997.
  • HotMETA A metadata repository currently indexes (gathers) abbreviated RDF
  • metadata.netMetadata Tools and Services, Metadata Schema Registry
  • Reggie the Metadata Editor. The aim of the Reggie Metadata Editor is to enable the easy creation of various forms of metadata with the one flexible program. As it stands, the Reggie applet can create metadata using the HTML 3.2 standard, the HTML 4.0 standard, the RDF (Resource Description Framework) format and the RDF Abbreviated format.
  • Application of RDF for Extensible Dublin Core Metadata
    This report attempts to use the XML Data Specification, together with the current proposals of the W3C Resource Description Framework (RDF) Working Group, to specify and use Dublin Core Metadata, including the ability to have: repeat and preserve element order, structure and group elements, and extend and inherit schemas.
  • http://www.dstc.edu.au/RDU/RDF/draft-iannella-vcard-rdf-00.txt This memo specifies a Resource Description Format (RDF) [RDF] encoding that corresponds to the vCard electronic business card profile defined by RFC 2425 [VCARD]. This specification provides equivalent functionality to the standard format defined by [VCARD]
IBM
  • RDF in Java This processor provides facilities for building RDF structures, navigating and querying them, manipulating them, and converting them to their equivalent XML forms. It also has facilities to perform I/O operations on RDF structures.
  • RDF for XML: Another technology from alphaWorks by IBMRDF for XML is an RDF processor written in Java for building, querying, and manipulating RDF structures and reading and writing them in XML forms. The current implementation conforms to the working draft dated 02/16/98 of the RDF Syntax and Model working group of the W3C.
Microsoft
Mozilla
Netscape
Home Pages
PRESS
Dublin Core
Misc

Copyright 1999-2001 Reinhold Klapsing