9 research outputs found

    A Semantic Importing Approach to Reusing Knowledge from Multiple Autonomous Ontology Modules

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    We present the syntax and semantics of a modular ontology language \logic{SHOIQP} to accomplish knowledge integration from multiple ontologies and knowledge reuse from context-specific points of view. Specifically, a \logic{SHOIQP} ontology consists of multiple ontology modules (each of which can be viewed as a \logic{SHOIQ} ontology) and concept, role and nominal names can be shared by ``importing\u27\u27 relations among modules. The proposed language supports contextualized interpretation, i.e., interpretation from the point of view of a specific package. We establish the necessary and sufficient constraints on domain relations (i.e., the relations between individuals in different local domains) to preserve the satisfiability of concept formulae, monotonicity of inference, and transitive reuse of knowledge

    Integrated distributed description logics

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    zimmermann2007aInternational audienceWe propose a Description-Logics-based language that extends standard DL with distributed capabilities. More precisely, it offers the possibility to formally describe the semantic relations that exist between two ontologies in a networked knowledge-based system. Contrary to Distributed Description Logics, it is possible to compose correspondences (or bridge rules), while still being able to hide some of the discrepancies between ontologies. Moreover, when ontologies have no nominals, no A-Box axioms, and correspondences are restricted to cross-ontology subsumption, the satisfiability of a local ontology is not influenced by ontology alignments and other ontologies, i.e., local deduction is invariant to the change of the outer system. Although we do not have a complete reasoning procedure, we provide inference rules and semantic properties, and a discussion on reasoning in this formalism

    An algebra of qualitative taxonomical relations for ontology alignments

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    inants2015aInternational audienceAlgebras of relations were shown useful in managing ontology alignments. They make it possible to aggregate alignments disjunctively or conjunctively and to propagate alignments within a network of ontologies. The previously considered algebra of relations contains taxonomical relations between classes. However, compositional inference using this algebra is sound only if we assume that classes which occur in alignments have nonempty extensions. Moreover, this algebra covers relations only between classes. Here we introduce a new algebra of relations, which, first, solves the limitation of the previous one, and second, incorporates all qualitative taxonomical relations that occur between individuals and concepts, including the relations "is a" and "is not". We prove that this algebra is coherent with respect to the simple semantics of alignments

    Reasoning on a network of aligned ontologies

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    zimmermann2008bInternational audienceIn the context of the Semantic Web or semantic peer to peer systems, many ontologies may exist and be developed independently. Ontology alignments help integrating, mediating or reasoning with a system of networked ontologies. Though different formalisms have already been defined to reason with such systems, they do not consider ontology alignments as first class objects designed by third party ontology matching systems. Correspondences between ontologies are often asserted from an external point of view encompassing both ontologies. We study consistency checking in a network of aligned ontologies represented in Integrated Distributed Description Logics (IDDL). This formalism treats local knowledge (ontologies) and global knowledge (inter-ontology semantic relations, i.e., alignments) separately by distinguishing local interpretations and global interpretation so that local systems do not need to directly connect to each other. We consequently devise a correct and complete algorithm which, although being far from tractable, has interesting properties: it is independent from the local logics expressing ontologies by encapsulating local reasoners. This shows that consistency of a IDDL system is decidable whenever consistency of the local logics is decidable. Moreover, the expressiveness of local logics does not need to be known as long as local reasoners can handle at least ALC

    A Survey of the First 20 Years of Research on Semantic Web and Linked Data

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    International audienceThis paper is a survey of the research topics in the field of Semantic Web, Linked Data and Web of Data. This study looks at the contributions of this research community over its first twenty years of existence. Compiling several bibliographical sources and bibliometric indicators , we identify the main research trends and we reference some of their major publications to provide an overview of that initial period. We conclude with some perspectives for the future research challenges.Cet article est une étude des sujets de recherche dans le domaine du Web sémantique, des données liées et du Web des données. Cette étude se penche sur les contributions de cette communauté de recherche au cours de ses vingt premières années d'existence. En compilant plusieurs sources bibliographiques et indicateurs bibliométriques, nous identifions les principales tendances de la recherche et nous référençons certaines de leurs publications majeures pour donner un aperçu de cette période initiale. Nous concluons avec une discussion sur les tendances et perspectives de recherche

    Analysis of knowledge transformation and merging techniques and implementations

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    scharffe2007bDealing with heterogeneity requires finding correspondences between ontologies and using these correspondences for performing some action such as merging ontologies, transforming ontologies, translating data, mediating queries and reasoning with aligned ontologies. This deliverable considers this problem through the introduction of an alignment life cycle which also identifies the need for manipulating, storing and sharing the alignments before processing them. In particular, we also consider support for run time and design time alignment processing

    Three semantics for distributed systems and their relations with alignment composition

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    Abstract. An ontology alignment explicitly describes the relations holding between two ontologies. A system composed of ontologies and alignments interconnecting them is herein called a distributed system. We give three different semantics of a distributed system, that do not interfere with the semantics of ontologies. Their advantages are compared with respect to allowing consistent merge of ontologies, managing heterogeneity and complying with an alignment composition operation. We show that only the first two variants, which differ from other proposed semantics, can offer a sound composition operation.

    Multilinguisation d'ontologies dans le cadre de la recherche d'information translingue dans des collections d'images accompagnées de textes spontanés

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    Le Web est une source proliférante d'objets multimédia, décrits dans différentes langues natu- relles. Afin d'utiliser les techniques du Web sémantique pour la recherche de tels objets (images, vidéos, etc.), nous proposons une méthode d'extraction de contenu dans des collections de textes multilingues, paramétrée par une ou plusieurs ontologies. Le processus d'extraction est utilisé pour indexer les objets multimédia à partir de leur contenu textuel, ainsi que pour construire des requêtes formelles à partir d'énoncés spontanés. Il est basé sur une annotation interlingue des textes, conservant les ambiguïtés de segmentation et la polysémie dans des graphes. Cette première étape permet l'utilisation de processus de désambiguïsation factorisés au niveau d'un lexique pivot (de lexèmes interlingues). Le passage d'une ontologie en paramètre du système se fait en l'alignant de façon automatique avec le lexique interlingue. Il est ainsi possible d'utiliser des ontologies qui n'ont pas été conçues pour une utilisation multilingue, et aussi d'ajouter ou d'étendre l'ensemble des langues et leurs couvertures lexicales sans modifier les ontologies. Un démonstrateur pour la recherche multilingue d'images, développé pour le projet ANR OMNIA, a permis de concrétiser les approches proposées. Le passage à l'échelle et la qualité des annotations produites ont ainsi pu être évalués.The World Wide Web is a proliferating source of multimedia objects described using various natural languages. In order to use semantic Web techniques for retrieval of such objects (images, videos, etc.), we propose a content extraction method in multilingual text collections, using one or several ontologies as parameters. The content extraction process is used on the one hand to index multimedia objects using their textual content, and on the other to build formal requests from spontaneous user requests. The process is based on an interlingual annotation of texts, keeping ambiguities (polysemy and segmentation) in graphs. This first step allows using common desambiguation processes at th elevel of a pivot langage (interlingual lexemes). Passing an ontology as a parameter of the system is done by aligning automatically its elements with the interlingual lexemes of the pivot language. It is thus possible to use ontologies that have not been built for a specific use in a multilingual context, and to extend the set of languages and their lexical coverages without modifying the ontologies. A demonstration software for multilingual image retrieval has been built with the proposed approach in the framework of the OMNIA ANR project, allowing to implement the proposed approaches. It has thus been possible to evaluate the scalability and quality of annotations produiced during the retrieval process.SAVOIE-SCD - Bib.électronique (730659901) / SudocGRENOBLE1/INP-Bib.électronique (384210012) / SudocGRENOBLE2/3-Bib.électronique (384219901) / SudocSudocFranceF
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