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Locality and applications to subsumption testing and interpolation in EL and some of its extensions [article]

Viorica Sofronie-Stokkermans
2013 arXiv   pre-print
We use possibilities of efficient local reasoning in such classes of algebras, to obtain uniform PTIME decision procedures for CBox subsumption in EL, EL^+ and extensions thereof.  ...  In this paper we show that subsumption problems in lightweight description logics (such as EL and EL^+) can be expressed as uniform word problems in classes of semilattices with monotone operators.  ...  We thank Stéphane Demri and Michael Zakharyaschev for asking the right questions and Carsten Ihlemann for his comments on a previous version of the paper.  ... 
arXiv:1311.2973v1 fatcat:mkkpdgnz6bch7ay6zu5aes57gi

Locality and Applications to Subsumption Testing in EL and Some of its Extensions

Viorica Sofronie-Stokkermans
2013 Scientific Annals of Computer Science  
We use possibilities of efficient local reasoning in such classes of algebras, to obtain uniform PTIME decision procedures for TBox and CBox subsumption in EL and EL + .  ...  In this paper we show that subsumption problems in the description logics EL and EL + can be expressed as uniform word problems in classes of semilattices with monotone operators.  ...  Acknowledgements This work was partly supported by the German Research Council (DFG) as part of the Transregional Collaborative Research Center "Automatic Verification and Analysis of Complex Systems"  ... 
doi:10.7561/sacs.2013.2.251 fatcat:iu7yjagcpfb4bkevvuh4kikbhu

Efficient TBox Subsumption Checking in Combinations of EL and (fragments of) FL0

Francis Gasse, Viorica Sofronie-Stokkermans
2011 International Workshop on Description Logics  
We study possibilities of combining (fragments) of the lightweight description logics FL0 and EL, and identify classes of subsumption problems in a combination of EL and Horn-FL0, which can be checked  ...  Since FL0 allows universal role restrictions and EL allows existential role restrictions, we thus have a framework where subsumption between expressions including both types of role restrictions (but for  ...  This work was partly supported by the German Research Council (DFG) as part of the Transregional Collaborative Research Center "Automatic Verification and Analysis of Complex Systems" (SFB/TR 14 AVACS)  ... 
dblp:conf/dlog/GasseS11 fatcat:kbtxg6qmtve7vmrechuaqoelfq

A Goal-Oriented Algorithm for Unification in $\mathcal{ELH}_{R+}$ w.r.t. Cycle-Restricted Ontologies [chapter]

Franz Baader, Stefan Borgwardt, Barbara Morawska
2012 Lecture Notes in Computer Science  
The Eager Extension rule solves a subsumption that contains only a variable X and some elements of S X on the left-hand side.  ...  In [2] , we extended the brute-force "guess and then test" NP-algorithm from [4] to the case of GCIs, which required the development of a new characterization of subsumption w.r.t. GCIs in EL.  ...  In order to generalize the bruteforce algorithm in this direction, we need to find a more general notion of locality.  ... 
doi:10.1007/978-3-642-35101-3_42 fatcat:frusn6jkonh7hi35npejt62aqu

Incremental Classification of Description Logics Ontologies

Bernardo Cuenca Grau, Christian Halaschek-Wiener, Yevgeny Kazakov, Boontawee Suntisrivaraporn
2010 Journal of automated reasoning  
In this paper, we propose a collection of techniques for incremental reasoning -that is, reasoning that reuses information obtained from previous versions of an ontology.  ...  This is an extended version of the papers published by the authors at ISWC-07 [7] and ESWC-08 [39]  ...  Council projects RINO (Reasoning Infrastructure for Ontologies and Instances) and ConDOR (Consequence-Driven Ontology Reasoning).  ... 
doi:10.1007/s10817-009-9159-0 fatcat:aflbig7cgbdjbeww4wxq447rme

Finding all justifications in Snomed ct

Boontawee Suntisrivaraporn
2013 ScienceAsia  
This article describes an extension of the method of finding one justification to one that finds all justifications for a given subsumption, introduces a SNOMED CT-specific optimization, and presents empirical  ...  Our extensive experiments on SNOMED CT show that (i) the proposed modularization-based approach makes it practicable to find all justifications in most cases in SNOMED CT; (ii) the first ten justifications  ...  Extensions to both locality-based modules and reachabiltiy-based modules have resulted in "nested locality-based modules" 38, 39 and "bidirectional reachability-based modules" 40, 41 .  ... 
doi:10.2306/scienceasia1513-1874.2013.39.079 fatcat:qsqnx4wkj5cnpmzt2r6danxf3m

Bridging the Gap between Tableau and Consequence-Based Reasoning

Yevgeny Kazakov, Pavel Klinov
2014 International Workshop on Description Logics  
Just like the similar style (deterministic) procedures for EL and Horn-SHIQ, our procedure explicitly derives subsumptions between concepts, but due to non-deterministic rules, not all of these subsumptions  ...  Instead, the consequences are only those subsumptions that can be derived regardless of the choices made in the application of the rules.  ...  side of some concept inclusion in O or of some D in the right-hand side of goal subsumptions.  ... 
dblp:conf/dlog/KazakovK14a fatcat:ktxdax2bobbjtiulhgxl2fthje

Extending Unification in EL to Disunification: The Case of Dismatching and Local Disunification

Franz Baader, Stefan Borgwardt, Barbara Morawska, Maribel Fernandez
2017 Logical Methods in Computer Science  
side of each negative constraint must be ground, and local solvability of disunification problems, where we consider only solutions that are constructed from terms occurring in the input problem.  ...  More precisely, we first show that dismatching can be reduced to local disunification, and then provide two complementary NP-algorithms for finding local solutions of disunification problems.  ...  The remainder of this article is organized as follows. Section 2 introduces syntax and semantics of EL and recalls some basic results about (dis)subsumption in EL.  ... 
doi:10.2168/lmcs-12(4:1)2016 fatcat:eotg3tw6pjgapgeoi2cigakmny

MORe: Modular Combination of OWL Reasoners for Ontology Classification [chapter]

Ana Armas Romero, Bernardo Cuenca Grau, Ian Horrocks
2012 Lecture Notes in Computer Science  
Reasoners are combined in a black-box modular manner, and the specifics of their implementation (and even of their reasoning technique) are irrelevant to our approach.  ...  Classification is a fundamental reasoning task in ontology design, and there is currently a wide range of reasoners highly optimised for classification of OWL 2 ontologies.  ...  This work was supported by the Royal Society, the EU FP7 project Optique and the EPSRC projects Score!, ExODA and LogMap.  ... 
doi:10.1007/978-3-642-35176-1_1 fatcat:43zga33p7rbt3fbysqgmtztn6a

ELK Reasoner: Architecture and Evaluation

Yevgeny Kazakov, Markus Krötzsch, Frantisek Simancik
2012 International Workshop on OWL Reasoner Evaluation  
ELK is a specialized reasoner for the lightweight ontology language OWL EL. The practical utility of ELK is in its combination of high performance and comprehensive support for language features.  ...  This system description presents the current state of ELK and experimental results with some difficult OWL EL ontologies.  ...  Acknowledgments This work was supported by the EU FP7 project SEALS and by the EPSRC projects ConDOR, ExODA and LogMap. The first author is supported by the German Research Council (DFG).  ... 
dblp:conf/ore/KazakovKS12 fatcat:mzrezipuwvfhdk4ajhvbmbbueu

ReAD: Delegate OWL Reasoners for Ontology Classification with Atomic Decomposition

Haoruo Zhao, Bijan Parsia, Uli Sattler
2020 Joint Ontology Workshops  
In this paper, we show that with the help of the atomic decomposition, a known ontology partition approach, these redundant subsumption tests can be avoided.  ...  Combining these delegate reasoners to classify one ontology gives potential benefits, but these may be offset by overheads or redundant subsumption tests.  ...  In [28] Chapter 7, the author designs, categorizes and organizes how to make a choice of the set of axioms for STs.  ... 
dblp:conf/jowo/ZhaoPS20 fatcat:3nnmjtefgfdetfkmb32x4idovm

Bidirectional Reachability-Based Modules

Riku Nortje, Arina Britz, Thomas Andreas Meyer
2011 International Workshop on Description Logics  
For acyclic E L TBoxes consisting of only primitive concept inclusions, all MinAs can be extracted without the need for subsumption testing.  ...  Bidirectional modules are related to nested locality modules, but are aimed specifically at MinA extraction and are generally smaller.  ...  Extension of the techniques presented here to more expressive DLs using hypergraph grammars, and relating it to the techniques and complexity results presented in [7] , are topics of further research.  ... 
dblp:conf/dlog/NortjeBM11 fatcat:g6eyr32vvzgw7l3ic6ms4tznf4

Restricted Role-value-maps in a Description Logic with Existential Restrictions and Terminological Cycles

Franz Baader
2003 International Workshop on Description Logics  
In a previous paper we have investigated subsumption in the presence of terminological cycles for the description logic EL, which allows conjunctions, existential restrictions, and the top concept, and  ...  In this paper we show that subsumption in EL (with or without cyclic definitions) remains polynomial even if one adds a certain restricted form of global role-value-maps to EL.  ...  Lemma 14 14 Let T be an EL-TBox, R an RBox, and T the completion of T w.r.t. R. If I is a model of R, then I is a model of T iff I is a model of T . In order to test subsumption w.r.t.  ... 
dblp:conf/dlog/Baader03 fatcat:chainmrc7nfyvdh6zvd6myx73y

Deciding Unifiability and Computing Local Unifiers in the Description Logic $\mathcal{E\!L}$ without Top Constructor

Franz Baader, Nguyen Thanh Binh, Stefan Borgwardt, Barbara Morawska
2016 Notre Dame Journal of Formal Logic  
On the other hand, unification in EL has been shown to be NP-complete, and thus of considerably lower complexity than unification in other description logics of similarly restricted expressive power.  ...  In addition to the decision problem, we also consider the problem of actually computing EL − -unifiers.  ...  Undecidability of unification in some extensions of K (for example, by the universal modality) was shown in [29] .  ... 
doi:10.1215/00294527-3555507 fatcat:furoxuvajnhbtdgqhqbeakoo24

OWL Reasoning: Subsumption Test Hardness and Modularity

Nicolas Matentzoglu, Bijan Parsia, Uli Sattler
2017 Journal of automated reasoning  
Modular reasoning is currently motivated by the potential for reducing the hardness of subsumption tests, reducing the number of necessary subsumption tests and integrating efficient delegate reasoners  ...  More than 50% of the tests did not change in hardness at all, however, and we observed large differences across reasoners.  ...  For example Pellet and its internal EL-classifier.  ... 
doi:10.1007/s10817-017-9414-8 pmid:30069069 pmcid:PMC6044258 fatcat:3s77puyxlngdfa2rf3iclvb3qy
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