Vivification

Vivification

Vivification is an operation on a description logic knowledge base to improve performance of a semantic reasoner. Vivification replaces a disjunction of concepts C_1 sqcup C_2 ldots sqcup C_n by the "least common subsumer" of the concepts C_1,C_2,ldots C_n.

The goal of this operation is to improve the performance of the reasoner by replacing a complex set of concepts with a single concept which subsumes the original concepts.

For example, consider the example given in (Cohen 92): Suppose we have the concept extrm{PIANIST(Jill)} vee extrm{ORGANIST(Jill)}. This concept can be vivified into a simpler concept extrm{KEYBOARD-PLAYER(Jill)}. This summarization leads to an approximation that may not be exactly equivalent to the original.

An approximation

Knowledge base vivification is not necessarily exact. If the reasoner is operating under the open world assumption we may get surprising results. In the previous example, if we replace the disjunction with the vivified concept, we will arrive at a surprising results.

First, we find that the reasoner will no longer classify Jill as either a pianist or an organist. Even though extrm{ORGANIST} and extrm{PIANIST} are the only two sub-classes, under the OWA we can no longer classify Jill as playing one or the other. The reason is that there may be another keyboard instrument (e.g. a harpsichord) that Jill plays but which does not have a specific subclass.

References

# Cohen, W.W., Borgida, A., Hirsh, H., Computing Least Common Subsumers in Description Logics, In: Proc. AAAI-92, AAAI Press/The MIT Press, 1992, pages 754--760. [http://citeseer.ist.psu.edu/cohen92computing.html CiteSeer]
# Baader, F., Kusters, R., Wolter F., Extensions to Description Logics. In F. Baader, D. Calvanese, D. McGuinness, D. Nardi, and P.F. Patel-Schneider, editors, The Description Logic Handbook: Theory, Implementation, and Applications. Cambridge University Press, 2003. http://citeseer.ist.psu.edu/baader03basic.html


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  • vivification — Vivification. s. f. v. La vivification des parties par les esprits, la vivification de l ame par la grace …   Dictionnaire de l'Académie française

  • Vivification — Viv i*fi*ca tion, n. [L. vivificatio: cf. vivification.] 1. The act of vivifying, or the state of being vivified; restoration of life; revival. Bacon. [1913 Webster] 2. (Physiol.) One of the changes of assimilation, in which proteid matter which… …   The Collaborative International Dictionary of English

  • Vivification — (v. lat.), Belebung, Lebendigmachung …   Pierer's Universal-Lexikon

  • vivification — index birth (emergence of young), revival Burton s Legal Thesaurus. William C. Burton. 2006 …   Law dictionary

  • vivification — vivifier [ vivifje ] v. tr. <conjug. : 7> • 1120; lat. ecclés. vivificare 1 ♦ Littér. Être le principe de vie de. ⇒ animer. Absolt Cette hypothèse « d une force qui vivifie » (Senancour). Relig. Être le principe de la vie éternelle,… …   Encyclopédie Universelle

  • VIVIFICATION — s. f. Action par laquelle on ranime, on vivifie. La vivification d un membre paralysé. Il n est point usité dans le langage médical …   Dictionnaire de l'Academie Francaise, 7eme edition (1835)

  • vivification — (vi vi fi ka sion ; en vers, de six syllabes) s. f. Action par laquelle on ranime, on vivifie. HISTORIQUE    XVIe s. •   La mortification de la chair et la vivification de l esprit, CALVIN 57. ÉTYMOLOGIE    Lat. vivificacio ; espagn. vivificacion …   Dictionnaire de la Langue Française d'Émile Littré

  • vivification — vivify ► VERB (vivifies, vivified) ▪ enliven or animate. DERIVATIVES vivification noun. ORIGIN Latin vivificare, from vivere to live …   English terms dictionary

  • vivification — noun see vivify …   New Collegiate Dictionary

  • VIVIFICATION — n. f. Action par laquelle on ranime, on vivifie …   Dictionnaire de l'Academie Francaise, 8eme edition (1935)

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