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Found 18 papers, 1 papers with code
On the Correspondence Between Monotonic Max-Sum GNNs and Datalog
Although there has been significant interest in applying machine learning techniques to structured data, the expressivity (i. e., a description of what can be learned) of such techniques is still poorly understood.
Explainable GNN-Based Models over Knowledge Graphs
In this paper, we propose a new family of GNN-based transformations of graph data that can be trained effectively, but where all predictions can be explained symbolically as logical inferences in Datalog---a well-known knowledge representation formalism.
Datalog Reasoning over Compressed RDF Knowledge Bases
Materialisation is often used in RDF systems as a preprocessing step to derive all facts implied by given RDF triples and rules.
Modular Materialisation of Datalog Programs
The semina\"ive algorithm can materialise all consequences of arbitrary datalog rules, and it also forms the basis for incremental algorithms that update a materialisation as the input facts change.
Stratified Negation in Limit Datalog Programs
There has recently been an increasing interest in declarative data analysis, where analytic tasks are specified using a logical language, and their implementation and optimisation are delegated to a general-purpose query engine.
Goal-Driven Query Answering for Existential Rules with Equality
We show empirically that our technique can significantly improve the performance of query answering, and that it can mean the difference between answering a query in a few seconds or not being able to process the query at all.
Optimised Maintenance of Datalog Materialisations
The Delete/Rederive (DRed) and the Backward/Forward (B/F) algorithms solve this problem for general datalog, but both contain steps that evaluate rules 'backwards' by matching their heads to a fact and evaluating the partially instantiated rule bodies as queries.
Stream Reasoning in Temporal Datalog
In recent years, there has been an increasing interest in extending traditional stream processing engines with logical, rule-based, reasoning capabilities.
Foundations of Declarative Data Analysis Using Limit Datalog Programs
Motivated by applications in declarative data analysis, we study $\mathit{Datalog}_{\mathbb{Z}}$---an extension of positive Datalog with arithmetic functions over integers.
Extending Consequence-Based Reasoning to SRIQ
Consequence-based calculi are a family of reasoning algorithms for description logics (DLs), and they combine hypertableau and resolution in a way that often achieves excellent performance in practice.
Handling owl:sameAs via Rewriting
Rewriting is widely used to optimise owl:sameAs reasoning in materialisation based OWL 2 RL systems.
Answering Conjunctive Queries over $\mathcal{EL}$ Knowledge Bases with Transitive and Reflexive Roles
Moreover, we show that, even for a restricted class of so-called arborescent acyclic queries, CQ answering over $\mathcal{EL}$ KBs becomes NP-hard in the presence of either transitive or reflexive roles.
Acyclicity Notions for Existential Rules and Their Application to Query Answering in Ontologies
Existential rules are closely related to the Horn fragments of the OWL 2 ontology language; furthermore, several prominent OWL 2 reasoners implement CQ answering by using the chase to materialise all relevant facts.
Reasoning over Ontologies with Hidden Content: The Import-by-Query Approach
There is currently a growing interest in techniques for hiding parts of the signature of an ontology Kh that is being reused by another ontology Kv.
Completeness Guarantees for Incomplete Ontology Reasoners: Theory and Practice
Since ontologies and typical queries are often fixed at application design time, our approach allows application developers to check whether a reasoner known to be incomplete in general is actually complete for the kinds of input relevant for the application.
Hypertableau Reasoning for Description Logics
We present a novel reasoning calculus for the description logic SHOIQ^+---a knowledge representation formalism with applications in areas such as the Semantic Web.
Computing Datalog Rewritings beyond Horn Ontologies
Rewriting-based approaches for answering queries over an OWL 2 DL ontology have so far been developed mainly for Horn fragments of OWL 2 DL.
Introducing Nominals to the Combined Query Answering Approaches for EL
So-called combined approaches answer a conjunctive query over a description logic ontology in three steps: first, they materialise certain consequences of the ontology and the data; second, they evaluate the query over the data; and third, they filter the result of the second phase to eliminate unsound answers.
