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Found 26 papers, 3 papers with code
Semantic Web and Creative AI -- A Technical Report from ISWS 2023
ISWS 2023 explored various intersections between Semantic Web technologies and creative AI.
Towards Propositional KLM-Style Defeasible Standpoint Logics
We introduce the logical system of Defeasible Restricted Standpoint Logic (DRSL) and define its syntax and semantics.
Non-monotonic Extensions to Formal Concept Analysis via Object Preferences
To this end, we show that the set of all typical concepts is a meet semi-lattice of the original concept lattice.
Enriching Ontologies with Disjointness Axioms using Large Language Models
Ontologies often lack explicit disjointness declarations between classes, despite their usefulness for sophisticated reasoning and consistency checking in Knowledge Graphs.
The Sticky Path to Expressive Querying: Decidability of Navigational Queries under Existential Rules
Extensive research in the field of ontology-based query answering has led to the identification of numerous fragments of existential rules (also known as tuple-generating dependencies) that exhibit decidable answering of atomic and conjunctive queries.
Derivation-Graph-Based Characterizations of Decidable Existential Rule Sets
This paper establishes alternative characterizations of very expressive classes of existential rule sets with decidable query entailment.
Pushing the Boundaries of Tractable Multiperspective Reasoning: A Deduction Calculus for Standpoint EL+
Standpoint EL is a multi-modal extension of the popular description logic EL that allows for the integrated representation of domain knowledge relative to diverse standpoints or perspectives.
Decidability of Querying First-Order Theories via Countermodels of Finite Width
We propose a generic framework for establishing the decidability of a wide range of logical entailment problems (briefly called querying), based on the existence of countermodels that are structurally simple, gauged by certain types of width measures (with treewidth and cliquewidth as popular examples).
Tractable Diversity: Scalable Multiperspective Ontology Management via Standpoint EL
The tractability of the lightweight description logic EL has allowed for the construction of large and widely used ontologies that support semantic interoperability.
Finite-Cliquewidth Sets of Existential Rules: Toward a General Criterion for Decidable yet Highly Expressive Querying
The FCS class properly generalizes the class of finite-expansion sets (FES), and for signatures of arity at most 2, the class of bounded-treewidth sets (BTS).
How to Agree to Disagree: Managing Ontological Perspectives using Standpoint Logic
By virtue of this result, existing highly optimised OWL reasoners can be used to provide practical reasoning support for ontology languages extended by standpoint modelling.
AGM Belief Revision, Semantically
As our second core contribution, we provide a characterization of all logics for which our result can be strengthened to assignments producing transitive preference relations (as in K&M's original work).
The Price of Selfishness: Conjunctive Query Entailment for ALCSelf is 2ExpTime-hard
In logic-based knowledge representation, query answering has essentially replaced mere satisfiability checking as the inferencing problem of primary interest.
A General Katsuno-Mendelzon-Style Characterization of AGM Belief Base Revision for Arbitrary Monotonic Logics
The AGM postulates by Alchourr\'{o}n, G\"{a}rdenfors, and Makinson continue to represent a cornerstone in research related to belief change.
Finite Model Theory of the Triguarded Fragment and Related Logics
The Triguarded Fragment (TGF) is among the most expressive decidable fragments of first-order logic, subsuming both its two-variable and guarded fragments without equality.
Knowledge Graphs Evolution and Preservation -- A Technical Report from ISWS 2019
Although linked open data (LOD) is one knowledge graph, it is the closest realisation (and probably the only one) to a public FAIR Knowledge Graph (KG) of everything.
A Journey to the Frontiers of Query Rewritability
This paper is about (first order) query rewritability in the context of theory-mediated query answering.
Databases
Satisfiability and Query Answering in Description Logics with Global and Local Cardinality Constraints
On the other hand, the satisfiability problem becomes undecidable if inverse roles are added to the languages.
Neural Machine Translating from Natural Language to SPARQL
SPARQL is a highly powerful query language for an ever-growing number of Linked Data resources and Knowledge Graphs.
On the Ontological Modeling of Trees
Trees -- i. e., the type of data structure known under this name -- are central to many aspects of knowledge organization.
Gradual Learning of Matrix-Space Models of Language for Sentiment Analysis
Learning word representations to capture the semantics and compositionality of language has received much research interest in natural language processing.
Bound Your Models! How to Make OWL an ASP Modeling Language
To exploit the Web Ontology Language OWL as an answer set programming (ASP) language, we introduce the notion of bounded model semantics, as an intuitive and computationally advantageous alternative to its classical semantics.
Worst-case Optimal Query Answering for Greedy Sets of Existential Rules and Their Subclasses
We provide a generic algorithm for query entailment under gbts, which is worst-case optimal for combined complexity with or without bounded predicate arity, as well as for data complexity and query complexity.
Nominals, Inverses, Counting, and Conjunctive Queries or: Why Infinity is your Friend!
Provided that queries contain only simple roles, our result also shows decidability of entailment of (unions of) conjunctive queries in the logic that underpins OWL 1 DL and we believe that the presented results will pave the way for further progress towards conjunctive query entailment decision procedures for the Description Logics underlying the OWL standards.
Modeling in OWL 2 without Restrictions
We then report on the results of evaluating several state-of-the-art OWL 2 DL reasoners on problems that use combinations of features in a way that the global restrictions are violated.
