Controlling services in a mobile context-aware infrastructure

Context-aware application behaviors can be described as logic rules following the Event-Control-Action (ECA) pattern. In this pattern, an Event models an occurrence of interest (e.g., a change in context); Control specifies a condition that must hold prior to the execution of the action; and an Action represents the invocation of arbitrary services. We have defined a Controlling service aiming at facilitating the dynamic configuration of ECA rule specifications by means of a mobile rule engine and a mechanism that distributes context reasoning activities to a network of context processing nodes. In this paper we present a novel context modeling approach that provides application developers and users with more appropriate means to define context information and ECA rules. Our approach makes use of ontologies to model context information and has been developed on top of web services technology

A Rule-Based Approach Towards Context-Aware User Notification Services

Pervasive Computing is the vision of technology that is invisibly embedded in our natural surroundings. Users are offered unobtrusive services that require minimal attention. In this paper the Awareness and Notification Service (ANS) is presented that enables to rapidly build applications that inform users about their environment. Additionally, the service offers notifications tailored to the user's preferences and current context. ANS takes a rule based approach based on the Event-Condition-Action pattern. Users specify when and what should be notified to them by using a convenient ANS rule language. This flexible mechanism allows to rapidly develop applications that provide context-aware notifications without the need to write programming code to activate rules, nor to implement personalized notifications

Using ontologies for modeling context-aware services platforms

This paper discusses the suitability of using ontologies for modeling context-aware services platforms. It addresses the directions of research we are following in the WASP (Web Architectures for Services Platforms) project. For this purpose a simple scenario is considered

Services Platforms for Context-Aware Applications

Context-aware services platforms aim at supporting the handling of contextual information in order to provide better user-tailored services. This paper addresses our current efforts towards a configurable and extensible services platform for context-aware applications. It discusses the use of a language and ontologies to cope with configurability and extensibility aspect

Developing situation-aware applications for disaster management with a distributed rule-based platform

In order to enhance interoperability and productivity in the develop-ment of situation-aware applications for disaster management, proper mecha-nisms and guidelines are required. They must address the lack of semantics in modelling emergency situations. In addition, the ever changing and unpredicta-ble nature of disaster scenarios present challenges for information processing and collaboration. This paper proposes a framework that combines the follow-ing elements: (i) a foundational ontology for temporal conceptualization; (ii) well-founded specifications of structural and behavioral models; (iii) a CEP en-gine based on a distributed rule-based platform for situation management; (iv) a model-driven approach. We illustrate the operation of the framework with a scenario for monitoring tuberculosis epidemy

Architectural support for context-aware applications: from context models to services platforms

Context-awareness has emerged as an important and desirable feature in ubiquitous applications. This feature deals with the ability of applications to utilize information about the user’s environment (context) in order to tailor services to the user’s current situation and needs. This thesis aims at providing an integrated solution for the development of context-aware systems. The main objective is to facilitate the development of context-aware applications, focusing on two aspects: on offering context modelling abstractions and on providing infrastructural support by means of a context handling platform. The context modelling abstractions provide application developers with proper conceptual foundations that can be extended and specialized with specific application requirements. The context handling platform allows application functionality to be delegated to the platform, which reduces application development effort, time and, therefore, costs. This allows application developers to focus on their core business, instead of being bothered with application realization details

Graduation Committee: University of Twente:

The internet is evolving from a data repository to a more complex service provisioning system. Besides the upcoming of enabling technologies for internet service provisioning like web services, also business to business integration can be seen as a driving force for this evolution. Therefore, a growing amount of electronic services is deployed on the internet. Before services can be used, they first have to be found. Service discovery is a mechanism for finding services. Current mechanisms are syntactic methods (i.e. they match service requests and descriptions of service offerings based on keywords) which often lead to a poor quality result. This thesis focuses on how the quality of the service discovery result can be improved. Service discovery quality denotes the extent to which a returned match is relevant for the user. This thesis consists of two parts. In the first part, a problem analysis on service discovery is presented. The second part uses knowledge from the problem analysis to create a new service discovery approach. Key aspects of this new approach are context-awareness, ontologies and semantic reasoning. Finally, this new approach is implemented in a prototype to be able t