Dynamic context management for pervasive applications

Abstract

euzenat2008cInternational audiencePervasive computing aims at providing services for human beings that interact with their environment, encompassing objects and humans who reside in it. Applications must be able to take into account the context in which users evolve, e.g., physical location, social or hierarchical position, current tasks as well as related information. These applications have to deal with the dynamic integration in the environment of new, and sometimes unexpected, elements (users or devices). In turn, the environment has to provide context information to newly designed applications. We describe an architecture in which context information is distributed in the environment and context managers use semantic web technologies in order to identify and characterize available resources. The components in the environment maintain their own context expressed in RDF and described through OWL ontologies. They may communicate this information to other components, obeying a simple protocol for identifying them and determining the information they are capable to provide. We show how this architecture allows the introduction of new components and new applications without interrupting what is working. In particular, the openness of ontology description languages makes possible the extension of context descriptions and ontology matching helps dealing with independently developed ontologies

An extended ontology-based context model and manipulation calculus for dynamic Web service processes

“…However, there is no widely accepted definition for context in information science. Context is defined and used in various applications in their own perspectives [36,21,18], in particular to define locative and temporal aspects in mobile [50] and ubiquitous system [28,33] applications. Service composition can be static or dynamic.…”

“…The previous work on context in pervasive and ubiquitous applications uses context ontologies, which are tightly coupled with individual applications [21]. In their work, a context ontology is a part of application-dependent middleware.…”

A Context-Aware Approach for Integrating Semantic Web Technologies onto Mobile Devices

“…Replacing the prevailing system-centric view of context-awareness by a user-centric view is suggested by [6], since context-awareness is an activity-driven process, centered around user activities. The advantages context provides to the Semantic Web are elaborated in [8] and [4], introducing an architecture for a context modeling and processing framework for pervasive applications ( [4]) as well as a context mechanism for the Semantic Web to support data aggregation ( [8]). …”

“…This model serves as the basis for collecting and interpreting sensed data, which must be done on different levels [4]. Machine learning techniques guarantee that the context model continually adapts according to the user's intentions and tasks.…”

“…Currently, Semantic Web based applications and services can hardly be deployed on mobile devices because of the lack of suitable implementations for RDF storage and management, although the necessity of Semantic Web technology and ontologies in particular for realizing a context-aware mobile computing infrastructure is broadly acknowledged [1,4]. In this thesis, we elaborate on the technical and conceptual background needed for integrating Semantic Web technology onto mobile devices and employ technologies such as RDF for the realization of a powerful, adaptable, and scalable context-aware infrastructure for harnessing contextual data that can be used for requesting ambient services and data sets from linked data repositories.…”