Dmitriy Zheleznyakov

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We study the problem of evolution for Knowledge Bases (KBs) expressed in Description Logics (DLs) of the DL-Lite family. DL-Lite is at the basis of OWL 2 QL, one of the tractable fragments of OWL 2, the recently proposed revision of the Web Ontology Language. We propose some fundamental principles that KB evolution should respect. We review known model and(More)
Evolution of Knowledge Bases (KBs) expressed in Description Logics (DLs) has gained a lot of attention recently. Recent studies of the topic mostly focused on model-based approaches (MBAs), where the evolution of a KB results in a set of models. For KBs expressed in tractable DLs, such as those of the DL-Lite family, which we consider here, it was shown(More)
We study the problem of updates for TBoxes represented in Description Logics of the DL-Lite family. DL-Lite is at the basis of OWL 2 QL, one of the tractable fragments of OWL 2, the recently proposed revision of the Web Ontology Language. In this paper, we address for the first time the problem of updating TBoxes. We propose some principles that TBox(More)
We present a description and analysis of the data access challenge in the Siemens Energy. We advocate for Ontology Based Data Access (OBDA) as a suitable Semantic Web driven technology to address the challenge. We derive requirements for applying OBDA in Siemens, review existing OBDA systems and discuss their limitations with respect to the Siemens(More)
In this paper we demonstrate a system SemFacet, that is a proof of concept prototype for our semantic faceted search approach. SemFacet is implemented on top of the Yago knowledge base, powered by the OWL 2 RL triple store RDFox, and the full text search engine Lucene. SemFacet has provided very encouraging results. Via logical reasoning SemFacet can(More)
Querying is an essential instrument for meeting ad hoc information needs; however, current approaches for querying semantic data sources mostly target technologically versed users. Hence, there is a need for methods that make it possible for users with limited technological skills to express relatively complex ad hoc information needs in an easy and(More)
The dynamic nature of ontology development has motivated the formal study of ontology evolution problems. This paper presents a logical framework that enables fine-grained investigation of evolution problems at a deductive level. In our framework, the optimal evolutions of an ontology O are those ontologies O′ that maximally preserve both the structure of(More)
The Optique European project 3 [6] aims at providing an end-to-end solution for scalable access to Big Data integration, where end users will formulate queries based on a familiar conceptualization of the underlying domain. From the users’ queries the Optique platform will automatically generate appropriate queries over the underlying integrated data,(More)