@inbook {814, title = {Seed Patterns for Modeling Trees}, booktitle = {Advances in Pattern-Based Ontology Engineering}, year = {2021}, pages = {48-67}, publisher = {IOS Press}, organization = {IOS Press}, abstract = {Trees {\textendash} i.e., the type of data structure known under this name {\textendash} are central to many aspects of knowledge organization. We investigate some central design choices concerning the ontological modeling of such trees. In particular, we consider the limits of what is expressible in the Web Ontology Language and provide a reusable ontology design pattern for trees.}, author = {Aaron Eberhart and David Carral and Pascal Hitzler and Hilmar Lapp and Sebastian Rudolph} } @conference {653, title = {On the Ontological Modeling of Trees}, booktitle = {8th Workshop on Ontology Design and Patterns - WOP2017}, year = {2017}, author = {David Carral and Pascal Hitzler and Hilmar Lapp and Sebastian Rudolph} } @conference {133, title = {All But Not Nothing: Left-Hand Side Universals for Tractable {OWL} Profiles}, booktitle = {Proceedings of the 11th International Workshop on OWL: Experiences and Directions (OWLED 2014) co-located with 13th International Semantic Web Conference on (ISWC 2014), Riva del Garda, Italy, October 17-18, 2014.}, volume = {1265}, year = {2014}, month = {10/2014}, pages = {97-108}, publisher = {CEUR-WS.org}, organization = {CEUR-WS.org}, abstract = {We show that occurrences of the universal quantifier in the left-hand side of general concept inclusions can be rewritten into EL++ axioms under certain circumstances. I.e., this intuitive modeling feature is available for OWL EL while retaining tractability. Furthermore, this rewriting makes it possible to reason over corresponding extensions of EL++ and Horn-SROIQ using standard reasoners.}, keywords = {description logics, Horn Logics, OWL}, url = {http://ceur-ws.org/Vol-1265/owled2014_submission_13.pdf}, author = {David Carral and Adila Krisnadhi and Sebastian Rudolph and Pascal Hitzler}, editor = {C. Maria Keet and Valentina A. M. Tamma} } @article {60, title = {Complexities of Horn Description Logics}, journal = {ACM Trans. Comput. Log.}, volume = {14}, year = {2013}, pages = {2}, abstract = {Description Logics (DLs) have become a prominent paradigm for representing knowledge bases in a variety of application areas. Central to leveraging them for corresponding systems is the provision of a favourable balance between expressivity of the knowledge representation formalism on the one hand, and runtime performance of reasoning algorithms on the other. Due to this, Horn description logics (Horn DLs) have attracted attention since their (worst-case) data complexities are in general lower than their overall (i.e. combined) complexities, which makes them attractive for reasoning with large sets of instance data (ABoxes). However, the natural question whether Horn DLs also provide advantages for schema (TBox) reasoning has hardly been addressed so far. In this paper, we therefore provide a thorough and comprehensive analysis of the combined complexities of Horn DLs. While the combined complexity for many Horn DLs studied herein turns out to be the same as for their non-Horn counterparts, we identify subboolean DLs where Hornness simplifies reasoning. We also provide convenient normal forms for Horn DLs.}, keywords = {computational complexity, description logics, Horn logic}, doi = {10.1145/2422085.2422087}, url = {http://doi.acm.org/10.1145/2422085.2422087}, author = {Markus Kr{\"o}tzsch and Sebastian Rudolph and Pascal Hitzler} } @conference {129, title = {An Ontology Design Pattern for Cartographic Map Scaling}, booktitle = {The Semantic Web: Semantics and Big Data, 10th International Conference, ESWC 2013, Montpellier, France, May 26-30, 2013. Proceedings}, volume = {7882}, year = {2013}, pages = {76{\textendash}93}, publisher = {Springer}, organization = {Springer}, abstract = {
The concepts of scale is at the core of cartographic abstraction and mapping. It defines which geographic phenomena should be displayed, which type of geometry and map symbol to use, which measures can be taken, as well as the degree to which features need to be exaggerated or spatially displaced. In this work, we present an ontology design pattern for map scaling using the Web Ontology Language (OWL) within a particular extension of the OWL RL profile. We explain how it can be used to describe scaling applications, to reason over scale levels, and geometric representations. We propose an axiomatization that allows us to impose meaningful constraints on the pattern, and, thus, to go beyond simple surface semantics. Interestingly, this includes several functional constraints currently not expressible in any of the OWL profiles. We show that for this specific scenario, the addition of such constraints does not increase the reasoning complexity which remains tractable.
}, keywords = {Map Scaling, Ontology Design Patterns, OWL}, doi = {10.1007/978-3-642-38288-8_6}, url = {http://dx.doi.org/10.1007/978-3-642-38288-8_6}, author = {David Carral and Simon Scheider and Krzysztof Janowicz and Charles Vardeman and Adila Krisnadhi and Pascal Hitzler}, editor = {Philipp Cimiano and {\'O}scar Corcho and Valentina Presutti and Laura Hollink and Sebastian Rudolph} } @book {290, title = {语义Web技术基础}, year = {2013}, publisher = {Tsinghua University Press}, organization = {Tsinghua University Press}, author = {Pascal Hitzler and Markus Kr{\"o}tzsch and Sebastian Rudolph} } @article {303, title = {OWL 2 Web Ontology Language: Primer (Second Edition)}, year = {2012}, month = {12/11/2012}, pages = {W3C Recommendation}, url = {http://www.w3.org/TR/owl2-primer}, author = {Pascal Hitzler and Markus Kr{\"o}tzsch and Bijan Parsia and Peter F. Patel-Schneider and Sebastian Rudolph} } @article {65, title = {Type-Elimination-Based Reasoning for the Description Logic SHIQbs using Decision Diagrams and Disjunctive Datalog}, journal = {Logical Methods in Computer Science}, volume = {8}, year = {2012}, abstract = {We propose a novel, type-elimination-based method for standard reasoning in the description logic SHIQbs extended by DL-safe rules. To this end, we first establish a knowledge compilation method converting the terminological part of an ALCIb knowledge base into an ordered binary decision diagram (OBDD) that represents a canonical model. This OBDD can in turn be transformed into disjunctive Datalog and merged with the assertional part of the knowledge base in order to perform combined reasoning. In order to leverage our technique for full SHIQbs, we provide a stepwise reduction from SHIQbs to ALCIb that preserves satisfiability and entailment of positive and negative ground facts. The proposed technique is shown to be worst-case optimal w.r.t. combined and data complexity.}, keywords = {datalog, decision diagrams, description logics, type elimination}, doi = {10.2168/LMCS-8(1:12)2012}, url = {http://dx.doi.org/10.2168/LMCS-8(1:12)2012}, author = {Sebastian Rudolph and Markus Kr{\"o}tzsch and Pascal Hitzler} } @conference {141, title = {Local Closed World Semantics: Grounded Circumscription for Description Logics}, booktitle = {Web Reasoning and Rule Systems - 5th International Conference, RR 2011, Galway, Ireland, August 29-30, 2011. Proceedings}, volume = {6902}, year = {2011}, month = {08/2011}, pages = {263-268}, publisher = {Springer}, organization = {Springer}, abstract = {We present an improved local closed world extension for description logics. It is based on circumscription, and deviates from previous circumscriptive description logics in that extensions of minimized predicates may contain only extensions of named individuals in the knowledge base. Besides an (arguably) higher intuitive appeal, the improved semantics is applicable to expressive description logics without loss of decidability.}, isbn = {978-3-642-23579-5}, doi = {10.1007/978-3-642-23580-1}, url = {http://dx.doi.org/10.1007/978-3-642-23580-1}, author = {Adila Krisnadhi and Kunal Sengupta and Pascal Hitzler}, editor = {Sebastian Rudolph and Claudio Gutierrez} } @conference {143, title = {Local Closed World Semantics: Keep it simple, stupid!}, booktitle = {Proceedings of the 24th International Workshop on Description Logics (DL 2011), Barcelona, Spain, July 13-16, 2011}, volume = {745}, year = {2011}, month = {07/2011}, publisher = {CEUR-WS.org}, organization = {CEUR-WS.org}, abstract = {A combination of open and closed-world reasoning (usually called local closed world reasoning) is a desirable capability of knowledge representation formalisms for Semantic Web applications. However, none of the proposals made to date for extending description logics with local closed world capabilities has had any significant impact on applications. We believe that one of the key reasons for this is that current proposals fail to provide approaches which are intuitively accessible for application developers and at the same time are applicable, as extensions, to expressive description logics such as SROIQ, which underlies the Web Ontology Language OWL. In this paper we propose a new approach which overcomes key limitations of other major proposals made to date. It is based on an adaptation of circumscriptive description logics which, in contrast to previously reported circumscription proposals, is applicable to SROIQ without rendering reasoning over the resulting language undecidable.}, keywords = {circumscription, closed world, decidability, Description Logic}, url = {http://ceur-ws.org/Vol-745/paper_12.pdf}, author = {Adila Krisnadhi and Kunal Sengupta and Pascal Hitzler}, editor = {Riccardo Rosati and Sebastian Rudolph and Michael Zakharyaschev} } @conference {142, title = {Nominal Schemas for Integrating Rules and Description Logics}, booktitle = {Proceedings of the 24th International Workshop on Description Logics (DL 2011), Barcelona, Spain, July 13-16, 2011}, volume = {745}, year = {2011}, month = {07/2011}, publisher = {CEUR-WS.org}, organization = {CEUR-WS.org}, abstract = {We propose an extension of SROIQ with nominal schemas which can be used like {\textquotedblleft}variable nominal concepts{\textquotedblright} within axioms. This feature allows us to express arbitrary DL-safe rules in description logic syntax. We show that adding nominal schemas to SROIQ does not increase its worst-case reasoning complexity, and we identify a family of tractable DLs SROELVn that allow for restricted use of nominal schemas.}, url = {http://ceur-ws.org/Vol-745/paper_39.pdf}, author = {Markus Kr{\"o}tzsch and Frederick Maier and Adila Krisnadhi and Pascal Hitzler}, editor = {Riccardo Rosati and Sebastian Rudolph and Michael Zakharyaschev} } @conference {98, title = {Paraconsistent Semantics for Hybrid MKNF Knowledge Bases}, booktitle = {Web Reasoning and Rule Systems - 5th International Conference, RR 2011}, volume = {6902}, year = {2011}, pages = {93{\textendash}107}, publisher = {Springer}, organization = {Springer}, address = {Galway, Ireland}, abstract = {Hybrid MKNF knowledge bases, originally based on the stable model semantics, is a mature method of combining rules and Description Logics (DLs). The well-founded semantics for such knowledge bases has been proposed subsequently for better efficiency of reasoning. However, integration of rules and DLs may give rise to inconsistencies, even if they are respectively consistent. Accordingly, reasoning systems based on the previous two semantics will break down. In this paper, we employ the four-valued logic proposed by Belnap, and present a paraconsistent semantics for Hybrid MKNF knowledge bases, which can detect inconsistencies and handle it effectively. Besides, we transform our proposed semantics to the stable model semantics via a linear transformation operator, which indicates that the data complexity in our paradigm is not higher than that of classical reasoning. Moreover, we provide a fixpoint algorithm for computing paraconsistent MKNF models.
}, doi = {10.1007/978-3-642-23580-1_8}, url = {http://dx.doi.org/10.1007/978-3-642-23580-1_8}, author = {Shasha Huang and Qingguo Li and Pascal Hitzler}, editor = {Sebastian Rudolph and Claudio Gutierrez} } @conference {309, title = {An Evolutionary Computing Approach for Reasoning in the Semantic Web}, booktitle = {Poster at DECOI2009, the International Workshop on Collective Intelligence andEvolution}, year = {2009}, address = {Leiden, The Netherlands}, author = {Gaston Tagni and Christophe Gueret and Stefan Schlobach and Sebastian Rudolph and Pascal Hitzler} } @book {293, title = {Foundations of Semantic Web Technologies}, series = {Textbooks in Computing}, year = {2009}, pages = {455}, publisher = {Chapman and Hall/CRC Press}, organization = {Chapman and Hall/CRC Press}, issn = {9781420090505}, author = {Pascal Hitzler and Markus Kr{\"o}tzsch and Sebastian Rudolph} } @article {304, title = {OWL 2 Web Ontology Language: Primer}, year = {2009}, month = {10/27/2009}, pages = {W3C Recommendation}, url = {http://www.w3.org/TR/2009/REC-owl2-primer-20091027}, author = {Pascal Hitzler and Markus Kr{\"o}tzsch and Bijan Parsia and Peter F. Patel-Schneider and Sebastian Rudolph} } @book {294, title = {Semantic Web Grundlagen}, year = {2008}, pages = {277}, publisher = {Springer textbook}, organization = {Springer textbook}, issn = {978-3-540-33993-9}, author = {Pascal Hitzler and Markus Kr{\"o}tzsch and Sebastian Rudolph and York Sure} }