Application-level Solution for Data integration in Ubiquitous Computing Environment

The Ubiquitous Computing envisions a world of communicating mobile devices and sensors. Advances in wireless communications raise users' expectations about the accessibility of information in Ubiquitous Computing environments. Getting meaningful information from disparate sensor nodes and/or mobile devices spread in Ubiquitous Computing environment is an urgent task. On the one hand, the heterogeneity of the sensor nodes makes share and finding data at the mobile devices and sink nodes much harder. On the other hand, nodes in Ubiquitous Computing environment are highly dynamic which means query planning in Ubiquitous Computing environment should be able to dynamically re-make their plan when the network conditions change due to intermittent connectivity. To address these two issues, this paper proposes a new service-oriented framework(called UCDS, standing for Ubiquitous Computing Data Services ) at application-level, which supports for semantic integration and querying of heterogeneous data sets distributed over the Ubiquitous Computing environment. We propose a RDF-View-based approach for mobile data mediation, and describe the service-composition-based query planning algorithm implemented in UCDS. We explore an ontology based approach to, mapping mobile data to data services (DS for short), publishing DS with the shared domain ontology. We also explore dynamically evolving service interface enabled by richly service description capability using the semantic web languages, and answering queries through DS composition. Experimental results show that the approach adopted by UCDS provides a better performance compared with the conventional approach.