The overall goal of this project is the development of a formal framework for repurposing ontologies. The motivation behind this proposal is twofold:

1. Ontologies are rarely provided in convenient and meaningful way for an end user
2. It is too costly to develop ontologies that correspond to every user's specific needs

The global goal is broken down into the following sub-tasks to be realized during this project: (a) Formal specification of the basic knowledge representation system (b) Implementation of the knowledge representation system (c) Formal specification and validation of a repurposing language (d) Integration of the repurposing language into the previously developed KR system (e) Formal specification of a simple inference engine for the basic language as well as the repurposing language (f) Integration of the inference engine into the KR system (g) Validation through the implementation of a prototype application (TARMED)

The central part of the proposed project is the formal specification and validation of a repurposing language. We want this language to respect the following requirements:

i. All repurposing operations have to leave the original ontology unmodified.
ii. All inferences made in the repurposed ontology have to remain sound and complete with respect to the original ontology.
iii. All inferences made in the repurposed ontology have to be sound and should be complete (if possible) with respect to the repurposed ontology.
iv. Mechanisms have to be provided to cascade operations realized on the instance level back into the original ontology.