Carlos Mencía

Efficient MUS Enumeration of Horn Formulae with Applications to Axiom Pinpointing

The enumeration of minimal unsatisfiable subsets (MUSes) finds a growing number of practical applications, that includes a wide range of diagnosis problems. As a concrete example, the problem of axiom pinpointing in the \(\mathcal {EL}\) family of description logics (DLs) can be modeled as the enumeration of the group-MUSes of Horn formulae. In turn, axiom pinpointing for the \(\mathcal {EL}\) family of DLs finds important applications, such as debugging medical ontologies, of which SNOMED CT is the best known example. The main contribution of this paper is to develop an efficient group-MUS enumerator for Horn formulae, HgMUS, that finds immediate application in axiom pinpointing for the \(\mathcal {EL}\) family of DLs. In the process of developing HgMUS, the paper also identifies performance bottlenecks of existing solutions. The new algorithm is shown to outperform all alternative approaches when the problem domain targeted by group-MUS enumeration of Horn formulae is axiom pinpointing for the \(\mathcal {EL}\) family of DLs, with a representative suite of examples taken from different medical ontologies.

Intensified iterative deepening A* with application to job shop scheduling

We propose a novel, exact any-time search strategy that combines iterative deepening

Optimally Scheduling a Job-Shop with Operators and Total Flow Time Minimization

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Efficient Axiom Pinpointing with EL2MCS

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MCS Extraction with Sublinear Oracle Queries

\text{ IDA}

Efficient Relaxations of Over-constrained CSPs

*) with depth-first search and we consider the job shop scheduling problem with makespan minimization as a test bed. The combination of these search strategies is done so that limited depth-first searches are issued from some of the states distributed along the frontier reached by