Artículos

CRIB: A Method for Integrity Constraint Checking on Knowledge Bases

CRIB: Método para la Comprobación de Restricciones de Integridad en Bases de Conocimiento

Julia Clemente¹, Angélica de Antonio² and Jaime Ramírez²

1 Universidad de Alcalá de Henares
Escuela Universitaria Politécnica
Departamento de Automática
Campus Universitario. Ctra. Madrid–Barcelona, Km. 33,600
28871 Alcalá de Henares, Madrid, Spain
e–mail: julia@aut.alcala.es

2 Facultad de Informática.
Universidad Politécnica de Madrid.
28660 Boadilla del Monte, Madrid, Spain.
e–mail: angelica@fi.upm.es, jramirez@fi.upm.es

Article received on october 15, 2003; accepted 01 february 28,2005

Abstract

The necessity of verification tools for Knowledge Based–Systems (KBSs), that help to guarantee a certain degree of quality and reliability of these systems will increase in the future when more critical systems are developed in areas such as industry, science, business, etc. One of the objectives of the KBSs verification is to assure the consistency and completeness of the Knowledge Base (KB). In this paper, a technique to detect possible inconsistencies or conflicting situations between the objects of the KB is described, and a tool called CRIB, that implements this technique, is presented. The generality of this technique, based on the checking of the Integrity Constraints (ICs) declared on the KB, will allow to apply it to different kinds of KBSs. In addition, the flexibility and the power of the ICs specification language will make it possible to detect a wide range of inconsistencies in a KB.

Keywords: Verification, Knowledge Based–System, Consistency.

Resumen

La necesidad de herramientas de verificación para Sistemas Basados en el Conocimiento (SBCs), que ayuden a garantizar un cierto grado de calidad y fiabilidad de estos sistemas aumentará en el futuro conforme más sistemas críticos sean desarrollados en áreas tales como la industria, la ciencia, los negocios, etc. Uno de los objetivos de la verificación de SBCs es asegurar la consistencia y la completitud de la Base de Conocimientos (BC). En este artículo se describe una técnica para detectar posibles inconsistencias o situaciones conflictivas entre los objetos de la BC, y se presenta una herramienta llamada CRIB, que implementa esta técnica. La generalidad de esta técnica, basada en la comprobación de las Restricciones de Integridad (Rls) declaradas en la BC, permite aplicarla a diferentes tipos de SBCs. Asimismo, la flexibilidad y la potencia del lenguaje de especificación de RIs hará posible detectar un amplio abanico de inconsistencias en una BC.

Palabras Clave: Verificación, Sistema Basado en el Conocimiento, Consistencia.

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