Ubiquitous networking empowered by Beyond 3G networking makes it possible for mobile users to access networked software services across heterogeneous infrastructures by resource-constrained devices. Heterogeneity and device limitedness creates serious problems for the development and deployment of mobile services that are able to run properly on the execution context and are able to ensures tha...

Context-aware systems typically use data sensed from the environment to drive adaptive behaviour. Sensed data is inherently imprecise and uncertain; in addition, new uncertainties are introduced when sensed data is fused with other data to infer context at the more abstract level of situations. We present an uncertainty model which aggregates context uncertainty and provides mechanisms to captu...

—Context-aware mobile computing aims at designing applications that automatically adapt their behaviors to the available location information and the available nearby sensors and devices. This is done in order to fulfill tasks in a way that suits users' current context best. To achieve this, context representation and manipulation are important issues, so as to establish formal context models. ...

Context-aware systems offer entirely new opportunities for application developers and for end users by gathering context data and adapting systems behaviour accordingly. Especially in combination with mobile devices these mechanisms are of high value and are used to increase usability tremendously. In this paper, we present common architecture principles of context-aware systems and derive a la...

Context awareness is the basis for a system’s ability to adapt to changing conditions of its environment. This ability is especially important in the public domain where a variety of systems is used, so-called public systems. Public systems perform in public spaces and are available to all people, instead of focusing on specific user groups. They also often integrate many different devices. Thu...

There is a growing interest in the use of context-aware systems, which can recognize user’s situational context and accordingly provide a desirable interaction with the user. However, the design, development, evaluation and deployment of context-aware systems are still at its infancy. In this paper, we propose an operational mechanism approach to context acquisition driven by the relevant depen...

Ensuring the consistent composition of context-dependent behavior is a major challenge in context-aware systems. Developers have to manually identify and validate existing interactions between behavioral adaptations, which is far from trivial. This paper presents a run-time model for the consistency management of context-dependent behavior, called context Petri nets. Context Petri nets provide ...

Context-aware systems in mobile and pervasive environments face many conflicting situations while collecting sensor data, processing sensor data to extract consistent and coherent high level context information, and disseminating that context information to assist in making decisions to adapt to the continuously evolving situations without diverting human attention. These conflicting situations...

Continuous location-dependent queries are key elements for the development of locationbased and context-aware services. While most work on location-dependent query processing has been mainly oriented towards outdoor environments, this paper develops an approach for the continuous processing of location-dependent queries over indoor moving objects. A prototype for handling those queries has been...