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08/08/2023
Current and Future Challenges in Knowledge Representation and Reasoning
Knowledge Representation and Reasoning is a central, longstanding, and a...
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06/13/2023
Temporalising Unique Characterisability and Learnability of Ontology-Mediated Queries
Recently, the study of the unique characterisability and learnability of...
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05/02/2023
Reverse Engineering of Temporal Queries Mediated by LTL Ontologies
In reverse engineering of database queries, we aim to construct a query ...
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03/08/2023
Definitions and (Uniform) Interpolants in First-Order Modal Logic
We first consider two decidable fragments of quantified modal logic 𝖲5: ...
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05/03/2022
Unique Characterisability and Learnability of Temporal Instance Queries
We aim to determine which temporal instance queries can be uniquely char...
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02/15/2022
Interpolants and Explicit Definitions in Extensions of the Description Logic EL
We show that the vast majority of extensions of the description logic ℰℒ...
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11/12/2021
First-Order Rewritability and Complexity of Two-Dimensional Temporal Ontology-Mediated Queries
Aiming at ontology-based data access to temporal data, we design two-dim...
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07/12/2021
How to Approximate Ontology-Mediated Queries
We introduce and study several notions of approximation for ontology-med...
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07/12/2021
Separating Data Examples by Description Logic Concepts with Restricted Signatures
We study the separation of positive and negative data examples in terms ...
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06/29/2021
On Free Description Logics with Definite Descriptions
Definite descriptions are phrases of the form 'the x such that φ', used ...
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11/19/2020
First Order-Rewritability and Containment of Conjunctive Queries in Horn Description Logics
We study FO-rewritability of conjunctive queries in the presence of onto...
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10/22/2020
From Conjunctive Queries to Instance Queries in Ontology-Mediated Querying
We consider ontology-mediated queries (OMQs) based on expressive descrip...
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07/06/2020
Living Without Beth and Craig: Explicit Definitions and Interpolants in Description Logics with Nominals
The Craig interpolation property (CIP) states that an interpolant for an...
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07/06/2020
Separating Positive and Negative Data Examples by Concepts and Formulas: The Case of Restricted Signatures
We study the separation of positive and negative data examples in terms ...
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07/03/2020
Logical Separability of Incomplete Data under Ontologies
Finding a logical formula that separates positive and negative examples ...
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07/03/2020
Living without Beth and Craig: Explicit Definitions and Interpolants in the Guarded Fragment
The guarded fragment of FO fails to have the Craig Interpolation Propert...
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04/15/2020
First-Order Rewritability of Ontology-Mediated Queries in Linear Temporal Logic
We investigate ontology-based data access to temporal data. We consider ...
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01/21/2020
A Journey into Ontology Approximation: From Non-Horn to Horn
We study complete approximations of an ontology formulated in a non-Horn...
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01/21/2020
A Journey into Ontology Approximation: From Non-Horn to Hon
We study complete approximations of an ontology formulated in a non-Horn...
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04/15/2019
Model Comparison Games for Horn Description Logics
Horn description logics are syntactically defined fragments of standard ...
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01/31/2019
Query Inseparability for ALC Ontologies
We investigate the problem whether two ALC ontologies are indistinguisha...
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09/01/2018
The Data Complexity of Ontology-Mediated Queries with Closed Predicates
In the context of ontology-mediated querying with description logics (DL...
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04/20/2018
Inseparability and Conservative Extensions of Description Logic Ontologies: A Survey
The question whether an ontology can safely be replaced by another, poss...
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04/18/2018
Dichotomies in Ontology-Mediated Querying with the Guarded Fragment
We study the complexity of ontology-mediated querying when ontologies ar...
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09/20/2017
Exact Learning of Lightweight Description Logic Ontologies
We study the problem of learning description logic (DL) ontologies in An...
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11/08/2016
The Data Complexity of Description Logic Ontologies
We analyze the data complexity of ontology-mediated querying where the o...
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01/23/2014
The Logical Difference for the Lightweight Description Logic EL
We study a logic-based approach to versioning of ontologies. Under this ...
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01/15/2014
The Complexity of Circumscription in DLs
As fragments of first-order logic, Description logics (DLs) do not provi...
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04/18/2013
Temporal Description Logic for Ontology-Based Data Access (Extended Version)
Our aim is to investigate ontology-based data access over temporal data ...
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01/28/2013
Ontology-based Data Access: A Study through Disjunctive Datalog, CSP, and MMSNP
Ontology-based data access is concerned with querying incomplete data so...
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04/14/2011