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Representing Ontologies Using Description Logics, Description Graphs, and Rules
- Artificial Intelligence
"... Description logics (DLs) are a family of state-of-the-art knowledge representation languages, and their expressive power has been carefully crafted to provide useful knowledge modeling primitives while allowing for practically effective decision procedures for the basic reasoning problems. Recent ex ..."
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Cited by 28 (6 self)
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Description logics (DLs) are a family of state-of-the-art knowledge representation languages, and their expressive power has been carefully crafted to provide useful knowledge modeling primitives while allowing for practically effective decision procedures for the basic reasoning problems. Recent experience with DLs, however, has shown that their expressivity is often insufficient to accurately describe structured objects—objects whose parts are interconnected in arbitrary, rather than tree-like ways. DL knowledge bases describing structured objects are therefore usually underconstrained, which precludes the entailment of certain consequences and causes performance problems during reasoning. To address this problem, we propose an extension of DL languages with description graphs—a knowledge modeling construct that can accurately describe objects with parts connected in arbitrary ways. Furthermore, to enable modeling the conditional aspects of structured objects, we also extend DLs with rules. We present an in-depth study of the computational properties of such a formalism. In particular, we first identify the sources of undecidability of the general, unrestricted formalism. Based on that analysis, we then investigate several restrictions of the general formalism that make reasoning decidable. We present practical evidence that such a logic can be used to model nontrivial structured objects. Finally, we present a practical decision procedure for our formalism, as well as tight complexity bounds. Key words: knowledge representation, description logics, structured objects, ontologies ⋆ This is an extended version of two papers published at WWW 2008 [29] and KR 2008 [28], respectively. ∗ Corresponding author.
OWL and rules
- In Reasoning Web, Semantic Technologies for the Web of Data - 7th International Summer School 2011
"... Abstract. The relationship between the Web Ontology Language OWL and rule-based formalisms has been the subject of many discussions and research investigations, some of them controversial. From the many at-tempts to reconcile the two paradigms, we present some of the newest developments. More precis ..."
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Cited by 21 (12 self)
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Abstract. The relationship between the Web Ontology Language OWL and rule-based formalisms has been the subject of many discussions and research investigations, some of them controversial. From the many at-tempts to reconcile the two paradigms, we present some of the newest developments. More precisely, we show which kind of rules can be mod-eled in the current version of OWL, and we show how OWL can be extended to incorporate rules. We finally give references to a large body of work on rules and OWL. 1
Representing Chemicals using OWL, Description Graphs and Rules
"... Abstract. Objects can be said to be structured when their representation also contains their parts. While OWL in general can describe structured objects, description graphs are a recent, decidable extension to OWL which support the description of classes of structured objects whose parts are related ..."
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Abstract. Objects can be said to be structured when their representation also contains their parts. While OWL in general can describe structured objects, description graphs are a recent, decidable extension to OWL which support the description of classes of structured objects whose parts are related in complex ways. Classes of chemical entities such as molecules, ions and groups (parts of molecules) are often characterised by the way in which the constituent atoms of their instances are connected via chemical bonds. For chemoinformatics tools and applications, this internal structure is represented using chemical graphs. We here present a chemical knowledge base based on the standard chemical graph model using description graphs, OWL and rules. We include in our ontology chemical classes, groups, and molecules, together with their structures encoded as description graphs. We show how role-safe rules can be used to determine parthood between groups and molecules based on the graph structures and to determine basic chemical properties. Finally, we investigate the scalability of the technology used through the development of an automatic utility to convert standard chemical graphs into description graphs, and converting a large number of diverse graphs obtained from a publicly available chemical database. Key words: chemistry, ontology, description graphs, rules 1
Judging Amy: Automated Legal Assessment using OWL 2
- In Proceedings of OWL: Experiences and Directions (OWLED 2008
, 2008
"... Judging Amy: Automated legal assessment using OWL 2 van de Ven, S.; Hoekstra, R.J.; Breuker, J.A.P.J.; Wortel, L.L.; el Ali, A.A. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other th ..."
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Cited by 8 (4 self)
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Judging Amy: Automated legal assessment using OWL 2 van de Ven, S.; Hoekstra, R.J.; Breuker, J.A.P.J.; Wortel, L.L.; el Ali, A.A. General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Abstract. One of the most salient tasks in law is legal assessment, and concerns the problem of determining whether some case is allowed or disallowed given an appropriate body of legal norms. In this paper we describe a system and Protégé 4 plugin, called OWL Judge, that uses standard OWL 2 DL reasoning for legal assessment. Norms are represented in terms of the LKIF Core ontology, as generic situation descriptions in which something (state, action) is deemed obliged, prohibited or permitted. We demonstrate the design patterns for defining the norms and actual cases. Furthermore we show how a DL classifier can be used to assess individual cases and automatically generate a lex specialis exception structure using OWL Judge. We illustrate our approach with a worked-out example of university library regulations.
Application of OWL 1.1 to Systems Engineering
"... Abstract. Current systems engineering languages, standards, and tools are restricted in certain aspects of their expressiveness and do not provide formal semantics. While there is a long history of attempts to use formal methods for engineering, up to now the formalisms have generally proved too har ..."
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Cited by 5 (2 self)
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Abstract. Current systems engineering languages, standards, and tools are restricted in certain aspects of their expressiveness and do not provide formal semantics. While there is a long history of attempts to use formal methods for engineering, up to now the formalisms have generally proved too hard to use, and the tools do not scale for large complex system development. A semantic integration framework that can integrate representations from multiple system engineering languages and tools could, however, have a significant impact on cost, schedule, and product integrity. We are exploring the potential for OWL 1.1 to provide such a semantic integration for the air system engineering domain. To determine the potential to use OWL 1.1 in this setting we are developing a prototypical air system ontology in OWL 1.1 and evaluating the use of the language for developing and reasoning about systems engineering concepts such as requirements and product structure. 1
Towards a model-driven approach for reverse engineering design patterns
- In Proc. 2nd International Workshop on Transforming and Weaving Ontologies in Model Driven Engineering (TWOMDE’09
, 2009
"... Abstract. The size and complexity of software systems is rapidly increasing. Meanwhile, the ability to understand and maintain such systems is decreasing almost as fast. Model Driven Engineering (MDE) promotes the notion of modeling to cope with software complexity; in this paper we report on our re ..."
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Abstract. The size and complexity of software systems is rapidly increasing. Meanwhile, the ability to understand and maintain such systems is decreasing almost as fast. Model Driven Engineering (MDE) promotes the notion of modeling to cope with software complexity; in this paper we report on our research that utilizes ontological modeling for understanding complex software systems. We focus the discussion on recovering design pattern information from source code. We thus argue that an effective recovery approach needs to utilize semantic reasoning to properly match an ontological representation of both: conceptual source code knowledge and design pattern descriptions. Since design patterns can take different forms when implemented in code, we argue that hardcoding their descriptions limits the flexibility and usability of a detection mechanism.
Modeling Ontologies Using OWL, Description Graphs, and Rules
"... Ontologies often describe structured objects, which consist of many parts interconnected in complex ways. Such objects abound in molecular biology and the clinical sciences. Clinical ontologies such as GALEN, the Foundational Model of Anatomy (FMA), and the National Cancer Institute (NCI) Thesaurus ..."
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Cited by 4 (1 self)
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Ontologies often describe structured objects, which consist of many parts interconnected in complex ways. Such objects abound in molecular biology and the clinical sciences. Clinical ontologies such as GALEN, the Foundational Model of Anatomy (FMA), and the National Cancer Institute (NCI) Thesaurus describe
The Representation of Structured Objects in DLs using Description Graphs ⋆
"... Applications of description logics (DLs) often require the representation of and reasoning with structured objects—that is, objects composed of parts connected in complex ways. Although DLs are general and powerful languages, they cannot describe arbitrarily connected structures. The description of ..."
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Cited by 2 (0 self)
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Applications of description logics (DLs) often require the representation of and reasoning with structured objects—that is, objects composed of parts connected in complex ways. Although DLs are general and powerful languages, they cannot describe arbitrarily connected structures. The description of structured objects
Use of OWL in the Legal Domain (Statement of Interest
- Proceedings of OWL: Experiences and Directions (OWLED 2008 DC
, 2008
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