On Computing Minimal EL -Subsumption Modules

International audienceIn the paper we study algorithms for computing minimal modules that are minimal w.r.t. set inclusion and that preserve the entailment of all EL- subsumptions over a signature of interest. We follow the black-box approach for finding one or all justifications by replacing the entailment tests with logical dif- ference checks, obtaining modules that preserve not only a given consequence but all entailments over a signature. Such minimal modules can serve to improve our understanding of the internal structure of large and complex ontologies. Addition- ally, several optimisations to speed up the computation of minimal modules are investigated. We present an experimental evaluation of an implementation of our algorithms by applying them on the medical ontologies Snomed CT and NCI