A new OWLAPI interface for HEX-programs applied to explaining contingencies in production planning

Peter Schüller
2020 European Conference on Artificial Intelligence  
Description Logics (DLs) and Logic Programs are formalisms for describing knowledge about the world. In industrial settings, DLs are often used to describe factories and inventories, and logic programs could be useful for planning production -if they can be integrated with DLs. We here introduce a variation of the DL Program formalism for integrating description logics with Answer Set Programming (ASP). We a new implementation based on OWLAPI and a use case in Explainable AI for production
more » ... ing. Our integration is based on the HEX formalism and the Hexlite solver. Different from previous work, we extend the integration interface to permit an arbitrary number of parallel modifications of the OWL ontology to be considered for the computation of a single answer set. This is useful to model changes of the planning domain over time, where each time step is a separate modification of the ontology. We present a case study towards the EU recommendations on 'Human-centered, trustworthy AI systems', concretely we present a production planning framework that can be challenged by users with alternative scenarios. With our case study we argue that Explainability in the context of planning is not about the rationale behind decisions (those are defined by formal semantics and by the program) but we argue that Explainability should mainly focus on the possibility of human operators to challenge the system and request alternative solutions under alternative assumptions. We provide the following examples to show that Logic Programming requires only very small modifications to provide insights by means of the following whatif questions: (i) which machines could be deactivated without preventing to reach the production goal and (ii) which product could be skipped to reach a reduced production goal in a shorter time limit.
dblp:conf/ecai/Schuller20 fatcat:wvrakyhcjjarrhzrliqsyoi2re