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The Yin/Yang Web: A Unified Model for XML Syntax and RDF Semantics
July/August 2003 (vol. 15 no. 4)
pp. 797-812

Abstract—XML is the W3C standard document format for writing and exchanging information on the Web. RDF is the W3C standard model for describing the semantics and reasoning about information on the Web. Unfortunately, RDF and XML—although very close to each other—are based on two different paradigms. We argue that, in order to lead the Semantic Web to its full potential, the syntax and the semantics of information need to work together. To this end, we develop a model theory for the XML XQuery 1.0 and XPath 2.0 Data Model, which provides a unified model for both XML and RDF. This unified model can serve as the basis for Web applications that deal with both data and semantics. We illustrate the use of this model on a concrete information integration scenario. Our approach enables each side of the fence to benefit from the other, notably, we show how the RDF world can take advantage of XML Schema description and XML query languages, and how the XML world can take advantage of the reasoning capabilities available for RDF. Our approach can also serve as a foundation for the next layer of the Semantic Web, the ontology layer, and we present a layering of an ontology language on top of our approach.

[1] T. Bray, J. Paoli, C. Sperberg-McQueen, and E. Maler, Extensible Markup Language (XML) 1.0 (second ed.) W3C Recommendation, Oct. 2000. http://www.w3.org/TRREC-xml.
[2] J. Cowan and R. Tobin, XML Information Set W3C Recommendation, Oct. 2001. http://www.w3.org/TR/xml-infoset.
[3] H. Thompson, D. Beech, M. Maloney, and N. Mendelsohn, XML Schema Part 1: Structures W3C Recommentation, May 2001. http://www.w3.org/TRxmlschema-1/.
[4] D. Chamberlin, D. Florescu, J. Robie, J. Simeon, and M. Stefanescu, XQuery 1.0: An XML Query Language June 2001. http://www.w3.org/TRxquery/.
[5] O. Lassila and R. Swick, Resource Description Framework (RDF) Model and Syntax Specification W3C Recommentation, Feb. 1999. http://www.w3.org/TRREC-rdf-syntax/.
[6] G. Karvounarakis, V. Christophides, D. Plexousakis, and S. Alexaki, Querying RDF Descriptions for Community Web Portals Proc. French Nat'l Database Conf., Oct. 2001. http://139.91.183.30:9090/RDFRQL/.
[7] L. Miller, Inkling: RDF Query Using SquishQL http://swordfish.rdfweb.orgrdfquery/, 2002.
[8] A.Y. Levy, A. Rajaraman, and J.J. Ordille, Querying Heterogeneous Information Sources Using Source Descriptions Proc. Int'l Conf. Very Large Databases, pp. 251-262, Sept. 1996.
[9] R.J. BayardoJr., W. Bohrer, R.S. Brice, A. Cichocki, J. Fowler, A. Helal, V. Kashyap, T. Ksiezyk, G. Martin, M.H. Nodine, M. Rashid, M. Rusinkiewicz, R. Shea, C. Unnikrishnan, A. Unruh, and D. Woelk, InfoSleuth: Semantic Integration of Information in Open and Dynamic Environments Proc. ACM Conf. Management of Data (SIGMOD), pp. 195-206, May 1997.
[10] B. Amann, I. Fundulaki, and M. Scholl, Integrating Ontologies and Thesauri for RDF Schema Creation and Metadata Querying Int'l J. Digital Libraries, 2000.
[11] Organization for the Advancement of Structured Information Standards http:/www.oasis-open.org/, 2003.
[12] D. Carlson, Modeling XML Applications with UML. Practical E-Business Applications. Addison-Wesley, 2001.
[13] M. Mani, D. Lee, and R.R. Muntz, Semantic Data Modeling Using XML Schemas Proc. 20th Int'l Conf. Conceptual Modeling (ER 2001), Nov. 2001.
[14] M. Fernández and J. Marsh, The XQuery 1.0 and XPath 2.0 Data Model W3C Working Draft, June 2001. http://www.w3.org/TRquery-datamodel/.
[15] The Description Logic Handbook: Theory, Implementation, and Applications, F. Baader, D. Calvanese, D.L. McGuinness, D. Nardi, and P.F. Patel-Schneider, eds. Cambridge Press, 2003.
[16] T. Berners-Lee, Why RDF Model is Different from the XML Model 1999. http://www.w3.org/DesignIssuesRDF-XML.html .
[17] S. Melnik, Bridging the Gap between RDF and XML Dec. 1999. http://www-db.stanford.edu/melnik/rdffusion. html .
[18] H. Boley, A Web Data Model Unifying XML and RDF Unpublished draft, Sept. 2001. http://www.dfki.uni-kl.de/boleyxmlrdf.html .
[19] XML Schema Part 0: Primer, W3C Recommendation, May 2001. http://www.w3.org/TRxmlschema-0/.
[20] I. Fundulaki, B. Amann, M. Scholl, C. Beeri, and A.-M. Vercoustre, Mapping XML Fragments to Community Web Ontologies Proc. Fourth Int'l Workshop Web and Databases, June 2001.
[21] J. Robie, L.M. Garshol, S. Newcomb, M. Biezinski, M. Fuchs, L. Miller, D. Brickley, V. Christophides, and G. Karvounarakis, The Syntactic Web: Syntax and Semantics on the Web Extreme Markup Languages, Aug. 2001.
[22] Enosys Markets http:/www.enosysmarkets.com, 2003.
[23] Nimble Technology http:/www.nimble.com, 2003.
[24] Y. Papakonstantinuo, H. Garcia-Molina, and J. Widom, “Object Exchange Across Heterogeneous Information Sources,” Proc. Int'l Conf. Data Engineering, pp. 251–260, 1995.
[25] M.F. Fernandez, D. Florescu, J. Kang, A.Y. Levy, and D. Suciu, System Demonstration Strudel: A Web-Site Management System Proc. ACM Conf. Management of Data (SIGMOD), May 1997.
[26] S. Cluet, C. Delobel, J. Simeon, and K. Smaga, Your Mediators Need Data Conversion! Proc. ACM Conf. Management of Data (SIGMOD), pp. 177-188, June 1998.
[27] C.K. Baru, V. Chu, A. Gupta, B. Ludascher, R. Marciano, Y. Papakonstantinou, and P. Velikhov, XML-Based Information Mediation for Digital Libraries ACM Conf. Digital Libraries, pp. 214-215, Aug. 1999.
[28] I. Manolescu, D. Florescu, D. Kossmann, F. Xhumari, and D. Olteanu, Agora: Living with XML and Relational Proc. Int'l Conf. Very Large Databases (VLDB), pp. 623-626, 2000.
[29] P. Hayes, RDF Semantics W3C Working Draft, Jan. 2003. http://www.w3.org/TRrdf-mt/.
[30] F. van Harmelen, P.F. Patel-Schneider, and I. Horrocks, A Model-Theoretic Semantics for DAML+OIL Mar. 2001. http://www.daml.org/2001/03model-theoretic-semantics.html .
[31] F. van Harmelen, P.F. Patel-Schneider, and I. Horrocks, Reference Description of the DAML+OIL (Mar. 2001) Ontology Markup Language Mar. 2001. http://www.daml.org/2001/03reference.html .
[32] X. Leroy, The Objective Caml System, Release 3.02, Documentation and User's Manual. Institut Nat'l de Recherche en Informatique et en Automatique, Nov. 1999. http:/caml.inria.fr/.
[33] Galax: The XQuery Implementation for Discriminating Hackers http://db.bell-labs.comgalax/, 2003.

Index Terms:
Semantic Web, RDF, XML, syntax, semantics, data model, RDF schema, XML schema, XQuery.
Citation:
Peter F. Patel-Schneider, J?r? Sim?on, "The Yin/Yang Web: A Unified Model for XML Syntax and RDF Semantics," IEEE Transactions on Knowledge and Data Engineering, vol. 15, no. 4, pp. 797-812, July-Aug. 2003, doi:10.1109/TKDE.2003.1209000
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