Santtu Toivonen

The DYNAMOS approach to support context-aware service provisioning in mobile environments

To efficiently make use of information and services available in ubiquitous environments, mobile users need novel means for locating relevant content, where relevance has a user-specific definition. In the DYNAMOS project, we have investigated a hybrid approach that enhances context-aware service provisioning with peer-to-peer social functionalities. We have designed and implemented a system platform and application prototype running on smart phones to support this novel conception of service provisioning. To assess the feasibility of our approach in a real-world scenario, we conducted field trials in which the research subject was a community of recreational boaters.

Ontologies with Semantic Web/Grid in Data Integration for OLAP

Traditionally, data used in OLAP (online analytical processing) have been limited to the contents of the data warehouse of a company. However, the needs for analysis are often more demanding and data are needed from different sources. In this article, we study how the semantics of data sources can be described to allow combining data from several sources into an OLAP cube. We apply Semantic Web technologies for defining an OWL/RDF ontology for OLAP data sources and OLAP cubes. These definitions are then utilised in OLAP cube formation by posing an OWL/RDF ontology-based query against them. We use Grid technologies to enhance the efficiency of processing and ensuring security. Our primary interest is in the cube construction (i.e., ETL process), and we assume that standard OLAP methods can be used for the actual analysis. Our tests show that the proposed approach can speed up the construction of an OLAP cube for ad hoc queries by supporting a high-level query language and reducing the amount of required data.

A Hybrid Model of Context-aware Service Provisioning Implemented on Smart Phones

Mobile users of future ubiquitous environments require novel means for locating relevant services available in their daily surroundings, where relevance has a user-specific definition. In this paper, we propose the hybrid service provisioning model which complements the traditional model of interaction service provider to consumer with peer-to-peer functionalities. In addition to being notified proactively and in a context-aware manner about services available in the surroundings, users can generate several types of contextual messages, attach them to services or to the environment, and share them with other peers. We have designed and implemented a platform that supports this hybrid service provisioning model. The current application prototype runs on commercial smart phones. To demonstrate the feasibility and technical deployability of our approach, we conducted field trials in which the research subject was a community of recreational boaters