Decision Support Tools for Ontological Engineering - Efficient Decision Support Systems: Practice and Challenges from Current to Future - page 63

Fig. 7. Unified ontology view
Fig. 8. P2P architecture
Projects can be used outside of the network by saving them in an XML file.
To support knowledge evolution, DFKE uses a generic ontology representation that was
developed for representing conceptualizations and refinements of an ontology (Obst &
Chan, 2005). Conceptualizations involve to be major changes to an ontology, while
refinements reflect minor changes. The major/minor versioning scheme proposed by (Klein
& Fensel, 2001) is used to keep track of the versions of the ontology as conceptualizations
and refinements are added. Removing a conceptualization can have serious problems on
other systems that depend on the conceptualization. Therefore, conceptualizations cannot be
removed. The DFKE uses the concept of monotonicity to guarantee that existing concepts
are not removed. The Class Editor helps support monotonicity by denying users the ability
to remove knowledge elements that have been marked as monotonic by DFKE.