Ontology Integration 1

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CmpE 583- Web Semantics Theory and
PracticeONTOLOGY INTEGRATION

• Atilla ELÇI
• Computer Engineering Department
• Eastern Mediterranean University

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Introduction

• SW data come associated with its ontology
• Combining data from different sources requires
  integration of their corresponding ontologies
• Integration of ontologies necessitates finding
  out terms that are same, like, and
  different in the ontologies to be integrated.
• Formation of the resultant ontology using a
  graphical, OWL, and other languages is required.

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Agenda

• Taxonomy
• Ontology
• Integrating ontologies.

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Overview of Taxonomies Smith et al

• The study of the general principles of scientific
  classification SYSTEMATICS OF CLASSIFICATION
  especially orderly classification of plants and
  animals according to their presumed natural
  relationships Merriam-Webster OnLine
  http//www.m-w.com/
• For a detailed account submit taxonomy at MW
  Rosetta Edition at A. Elçis home page.
• The classification of information entities in
  the form of a hierarchy, according to the
  presumed relationships of the real-world entities
  that they represent
• Class structure
• A simple taxonomy Ref. Figure 7.1
• Generalization vs. specialization Ref. Figure
  7.2
• Tabular vs. tree forms Ref. Table 7.1 and Figure
  7.4.

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Use of Taxonomies

• Examples
• Table 7.2 The Dewey Decimal System A Taxonomy
• Table 7.3 The Dewey Decimal System 500 Natural
  Sciences and Mathematics.

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Ontology Spectrum

• The following concepts all attempt to address
  issues in representing, classifying, and
  disambiguating semantic content (meaning)
  taxonomies, thesauri, conceptual models, and
  logical theories.
• Figure 7.5 The ontology spectrum Weak to strong
  semantics.
• Taxonomy part-of, subclass-of relationship
• Thesaurus equivalence, homographic,
  hierarchical, and associative relationships
  (Table 7.4).
• Logical theory A set of axioms, inference rules,
  and theorems. In a logical theory, one can
  express the semantics of a model to the highest
  degree possible.

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Ontology Spectrum (continued)

• Ontology An ontology defines the common words
  and concepts (meanings) used to describe and
  represent an area of knowledge, and so
  standardizes the meanings.
• An ontology includes the following
• Classes (general things) in the many domains of
  interest
• Instances (particular things)
• Relationships among those things
• Properties (and property values) of those things
• Functions of and processes involving those things
• Constraints on and rules involving those things.

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Ontology Integration (in passing)

• Data/Ontology Integration Systems Baojie-a
• Mostly DB integration cases.
• Bibliography on Ontology integration Baojie-b.
• Appears more like a wizardry at this time.

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Ontology Integration Methods

• Probabilistic ontology mapping with explicit
  info
• Sushama Prasad et al., "A Tool For Mapping
  Between Two Ontologies Using Explicit
  Information", InProceedings, AAMAS 2002 Workshop
  on Ontologies and Agent Systems, July 2002.
• Context brokerage
• Harry Chen et al., "Semantic Web in in the
  Context Broker Architecture", InProceedings,
  Proceedings of PerCom 2004, March 2004.
• Smart environment
• Harry Chen et al., "Intelligent Agents Meet the
  Semantic Web in Smart Spaces", Article, IEEE
  Internet Computing, November 2004.
• Ontology ranking
• Li Ding et al., "Swoogle A Search and Metadata
  Engine for the Semantic Web", InProceedings,
  Proceedings of the Thirteenth ACM Conference on
  Information and Knowledge Management , November
  2004.
• Graphical methods
• tba.
• Summary of Combining and Relating Ontologies
• Article by M. Klein Klein.

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Where to Get More Information?

• Smith et al Chapter 7 - Undstanding Taxonomies.
  In The Semantic Web A Guide to the Future of
  XML, Web Services, and Knowledge Management, 1st
  edition, by Kevin T. Smith, Michael C. Daconta,
  Leo J. Obrst. John Wiley Sons, 2003.
  ISBN0471432571. Available as e-book at ACM
  Professional Development Center.
• Baojie-a Data/Ontology Integration Systems
• Baojie-b Bibliography on Ontology integration
• Klein M. Klein, Combining and Relating
  Ontologies an Analysis of Problems and
  Solutions, In Proc. The 17th Intl Joint Conf.
  On Artificial Intelligence (IJCAI-01), Workshop
  on Ontologies and Information Sharing, Vol. 47,
  pp53-62, Seattle, WA, USA, August 2001.