We have built a virtual data integration system which extends the BIRN Mediator[1] to include OWL 2 ontologies where these ontologies are used as domain schema. This mediator integrates data from multiple, heterogeneous sources. This data integration system rewrites conjunctive queries using LAV views defined over a DL-Lite ontology. This is an important problem in query optimization, data inte...

Respiratory epithelium expresses nitric oxide synthase 2 (NOS2) continuously in vivo; however, mechanisms responsible for its expression are only partially understood. We definitively identify an autocrine mechanism of induction and maintenance of NOS2 in human airway epithelial cells through the synthesis and secretion of a soluble mediator. Short exposure of human airway cells to interferon (...

By collaboration, domains share resources effectively. To maintain security properties of individual domains during collaboration is a key issue. When domains employing heterogeneous RBAC policies collaborate via crossdomain role-role mappings, their locally-defined separation of duty constraints face the risk of breaching. We present the requirements for constraint-secure interoperation, prohi...

Mediator systems federate and integrate data from disparate sources in order to elicit information that the individual sources cannot provide independently. The standard mediator architecture employs wrappers that translate heterogenous source data into a common (often semistructured) data model like XML. A “mediation engineer” provides an integrated view definition (IVD) on the wrapped XML sou...

The complexity and richness of geospatial data create specific problems in heterogeneous data integration. To deal with this type of data integration, we propose a spatial mediator embedded in a large distributed mobile environment (GeoGrid). The spatial mediator takes a user request from a field application and uses the request to select the appropriate data sources, constructs subqueries for ...

Case-based reasoning is a reasoning method that capitalizes on previous experience. In case-based reosoning, a new problem is solved in a way that is anologous to a previous similar problem. Case-bosed reasoning can improve problem-solving behavior In several ways: by providing reasoning shortcuts, by worning of the potential for error, and by suggesting a focus for reasoning. The MEDIATOR was ...

In this paper we propose a mediator architecture for the querying and integration of Web-accessible XML data sources. Our contributions are (i) the definition of a simple but expressive mapping language, following the local as view approach and describing XML resources as local views of some global schema, and (ii) efficient algorithms for rewriting user queries according to existing source des...

The heterogeneous data on the web is an increasingly important field of data sharing and integrating with diverse sources for retrieving suitable information using search engines. These heterogeneous data sources from distributed systems are easily interpretable to humans, but hardly understandable to machines. In this regard, the main focus of this research is to address the issues of spatial ...

An important aspect of research on software objects, components, and component-based applications concerns their interoperation. Is their interoperation technically possible? Which elements are responsible for the software objects’ incompatibility? Is compatibility a responsibility of the objects or of their underlying architectures? In this article we discuss the object compatibility problems,...