A Semantic Approach for Description and Ranked Matching of Services in Pervasive Environments

With the recent developments in technology, new and diverse devices are being introduced into the pervasive world. This has raised new challenges for the discovery of devices and their services in dynamic environments. The existing approaches such as Jini [AOSJ99], UPnP [UPnP06], etc., describe services at a syntactic level and the matching mechanisms in these approaches are limited to syntactic comparisons based on attributes or interfaces. In order to overcome the limitations of these approaches, there has been an increasing interest in the use of Semantic Web technologies to support the description and matching of services. This paper proposes a semantic matching framework to facilitate effective discovery of device based services in pervasive environments. This offers a ranking mechanism that will order the available services in the order of their suitability; the evaluation of the experimental results have indicated that the results correlate well with human perception

A Pragmatic Approach for the Semantic Description and Matching of Pervasive Resources

The increasing popularity of personal wireless devices has raised new demands for the efficient discovery of heterogeneous devices and services in pervasive environments. With the advancement of the electronic world, the diversity of available services is increasing rapidly. %This raises new demands for the efficient discovery and location of heterogeneous services and resources in dynamically changing environments. Traditional approaches for service discovery describe services at a syntactic level and the matching mechanisms available for these approaches are limited to syntactic comparisons based on attributes or interfaces. In order to overcome these limitations, there has been an increased interest in the use of semantic description and matching techniques to support effective service discovery. In this paper, we present a semantic matching approach to facilitate the discovery of device-based services in pervasive environments. The approach includes a ranking mechanism that orders services according to their suitability and also considers priorities placed on individual requirements in a request during the matching process. The solution has been systematically evaluated for its retrieval effectiveness and the results have shown that the matcher results agree reasonably well with human judgement. Another important practical concern is the efficiency and the scalability of the semantic matching solution. Therefore, we have evaluated the scalability of the proposed solution by investigating the variation in matching time in response to increasing numbers of advertisements and increasing request sizes, and have presented the empirical results

Composition and Self-Adaptation of Service-Based Systems with Feature Models

The adoption of mechanisms for reusing software in pervasive systems has not yet become standard practice. This is because the use of pre-existing software requires the selection, composition and adaptation of prefabricated software parts, as well as the management of some complex problems such as guaranteeing high levels of efficiency and safety in critical domains. In addition to the wide variety of services, pervasive systems are composed of many networked heterogeneous devices with embedded software. In this work, we promote the safe reuse of services in service-based systems using two complementary technologies, Service-Oriented Architecture and Software Product Lines. In order to do this, we extend both the service discovery and composition processes defined in the DAMASCo framework, which currently does not deal with the service variability that constitutes pervasive systems. We use feature models to represent the variability and to self-adapt the services during the composition in a safe way taking context changes into consideration. We illustrate our proposal with a case study related to the driving domain of an Intelligent Transportation System, handling the context information of the environment.Work partially supported by the projects TIN2008-05932, TIN2008-01942, TIN2012-35669, TIN2012-34840 and CSD2007-0004 funded by Spanish Ministry of Economy and Competitiveness and FEDER; P09-TIC-05231 and P11-TIC-7659 funded by Andalusian Government; and FP7-317731 funded by EU. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Resource Discovery Services for Grid Computing Training

Resource discovery is a core function of e-learning. While initially confined to library environments, it has become pervasive, partly due to the advent of web-based searching and also service-oriented approach. The latter is the focus of this paper as resource discovery (web) services enable existing resources to be identified from a source (library) and re-purposed for educational purposes in other systems such as virtual learning environments. This paper describes the development of such resource discovery services developed as part of an initiative to pilot e-learning and a shared digital library infrastructure for Grid Computing training projects in Europe. The development is also related to a project funded by the UK Joint Information Systems Committee (JISC) on publisher metadata interoperability. The resource discovery services correspond to an emerging international service-oriented framework for developing e-learning. This paper also provides an overview of the framework and the use-scenarios in which the resource discovery services have been deployed