The Knowledge Model of Protégé-2000: Combining Interoperability and Flexibility

  • Natalya Fridman Noy
  • Ray W. Fergerson
  • Mark A. Musen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1937)


Knowledge-based systems have become ubiquitous in recent years. Knowledge-base developers need to be able to share and reuse knowledge bases that they build. Therefore, interoperability among different knowledgerepresentation systems is essential. The Open Knowledge-Base Connectivity protocol (OKBC) is a common query and construction interface for frame-based systems that facilitates this interoperability. Protégé-2000 is an OKBCcompatible knowledge-base-editing environment developed in our laboratory. We describe Protégé-2000 knowledge model that makes the import and export of knowledge bases from and to other knowledge-base servers easy. We discuss how the requirements of being a usable and configurable knowledge-acquisition tool affected our decisions in the knowledge-model design. Protégé-2000 also has a flexible metaclass architecture which provides configurable templates for new classes in the knowledge base. The use of metaclasses makes Protégé-2000 easily extensible and enables its use with other knowledge models. We demonstrate that we can resolve many of the differences between the knowledge models of Protégé-2000 and Resource Description Framework (RDF)-a system for annotating Web pages with knowledge elements-by defining a new metaclass set. Resolving the differences between the knowledge models in declarative way enables easy adaptation of Protégé-2000 as an editor for other knowledgerepresentation systems.


Resource Description Framework Construction Interface Resource Description Framework Schema Maximum Salary Primitive Data Type 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Natalya Fridman Noy
    • 1
  • Ray W. Fergerson
    • 1
  • Mark A. Musen
    • 1
  1. 1.Stanford Medical InformaticsStanford UniversityStanford

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