Publicaties
Gekozen filters:
Gekozen filters:
SHACL: A description logic in disguise Universiteit Hasselt Vrije Universiteit Brussel
SHACL is a W3C-proposed language for expressing structural constraints on RDF graphs. In recent years, SHACL's popularity has risen quickly. This rise in popularity comes with questions related to its place in the semantic web, particularly about its relation to OWL (the de facto standard for expressing ontological information on the web) and description logics (which form the formal foundations of OWL). We answer these questions by arguing that ...
Compacting Boolean formulae for inference in probabilistic logic programming KU Leuven
Knowledge compilation converts Boolean formulae for which some inference tasks are computationally expensive into a representation where the same tasks are tractable. ProbLog is a state-of-the-art Probabilistic Logic Programming system that uses knowledge compilation to reduce the expensive probabilistic inference to an efficient weighted model counting. Motivated to improve ProbLog's performance we present an approach that optimizes Boolean ...
Approximation fixpoint theory and the semantics of logic and answers set programs KU Leuven
Approximation Fixpoint Theory was developed as a fixpoint theory of lattice operators that provides a uniform formalization of four main semantics of three major nonmonotonic reasoning formalisms. The aim of this paper is, first, to clarify the application of this fixpoint theory to define the stable and well-founded semantics of logic programs, and second, to show the remarkable power of this theory for defining natural and elegant versions of ...
Declarative Local Search for Predicate Logic KU Leuven
© 2019, Springer Nature Switzerland AG. In this paper we introduce a framework built on top of the Knowledge Base System, which allows local search heuristics to be synthesized from their formal descriptions. It is introduced as a new inference to solve optimization problems in. To model a local search heuristic, users need to specify its components, among which neighbourhood moves are the most important. Two types of neighbourhood moves, namely ...
Adaptive fuzzy logics for contextual hedge interpretation Universiteit Gent
The article presents several adaptive fuzzy hedge logics. These logics are designed to perform a specific kind of hedge detection. Given a premise set Γ that represents a series of communicated statements, the logics can check whether some predicate occurring in Γ may be interpreted as being (implicitly) hedged by technically, strictly speaking or loosely speaking, or simply non-hedged. The logics take into account both the logical constraints ...
Towards Possibilistic Fuzzy Answer Set Programming Vrije Universiteit Brussel
Fuzzy answer set programming (FASP) is a generalization of answer set programming to continuous domains. As it can not readily take uncertainty into account, however, FASP is not suitable as a basis for approximate reasoning and cannot easily be used to derive conclusions from imprecise information. To cope with this, we propose an extension of FASP based on possibility theory. The resulting framework allows us to reason about uncertain ...
Grounded fixpoints KU Leuven
Algebraical fixpoint theory is an invaluable instrument for studying semantics of logics. For example, all major semantics of logic programming, autoepistemic logic, default logic and more recently, abstract argumentation have been shown to be induced by the different types of+fixpoints defined in approximation fixpoint theory (AFT). In this paper, we add a new type of fixpoint to AFT: a grounded fixpoint of lattice operator O : L → L is defined ...
Grounded fixpoints KU Leuven
Algebraical fixpoint theory is an invaluable instrument for studying semantics of logics. For example, all major semantics of logic programming, autoepistemic logic, default logic and more recently, abstract argumentation have been shown to be induced by the different types of+fixpoints defined in approximation fixpoint theory (AFT). In this paper, we add a new type of fixpoint to AFT: a grounded fixpoint of lattice operator O : L → L is defined ...