Much research on context quality in context-aware systems divides into two strands: (1) the qualitative identi cation of quality measures and (2) the use of uncertain reasoning techniques. In this paper, we combine these two strands, exploring the problem of how to identify and propagate quality through the di erent context layers in order to support the context reasoning process. We present a ...

Interrupting users engaged in tasks typically has negative effects on their task completion time, error rate, and affective state. Empirical research has shown that these negative effects can be mitigated by deferring interruptions until more opportune moments in a user’s task sequence. However, existing systems that reason about when to interrupt do not have access to models of user tasks that...

Often context-aware systems consider the environment a defined element. Meanwhile reality is full of vagueness and uncertainty. Taking into account these aspects we can provide a more grounded and precise picture of the environment, creating context-aware systems that are more flexible and reliable. It also provides a more accurate inference process, making possible to consider the quality of t...

Context-aware systems must be able to deal with uncertain context information. We propose a generic context architecture and representation that incorporates the uncertainty of context elements in terms of upper and lower bounds of probabilities. It is shown how opinion nets can be used to reason with these upper and lower bound probabilities. In this way it is possible to combine ambiguous or ...

Context-aware systems acquire and integrate multi-faceted knowledge about their environments in order to make decisions. A number of attempts to build frameworks for context-aware systems have been made, but these have not provided adequate support for context-aware access control. In this paper, we present a framework for context-aware access control and its prototype implementation. The frame...

This paper presents a framework for building user interfaces for context-aware service management. It enables us to easily deploy context-aware services at computers through user-friendly manipulations to edit documents and monitor changes and services in the real world. It is constructed as a compound document framework whose the structural composition of visual components can be adapted to ch...

Nowadays, numerous journals and conferences have published articles related to context-aware systems, indicating many researchers’ interest. Therefore, the goal of this paper is to review the works that were published in journals, suggest a new classification framework of context-aware systems, and explore each feature of classification framework. This paper is based on a literature review of c...

Ubiquitous computing applications must have access to context information to provide context-aware services. The literature reports on applications that process and store context information as part of their functionality and also on reusable infrastructures dedicated to capturing, storing and processing context information. We advocate that infrastructures aimed at supporting context-aware app...

Context-aware systems observe the user’s current context and apply this information to the user’s benefit. When implementing context-awareness, several issues need to be considered and this paper concentrates on presenting the context information to the user. The key components needed to construct the context are identified, and a model, which allows using different visualization techniques for...

The existing personalization systems typically base their services on general user models that ignore the issue of context-awareness. This position paper focuses on developing mechanisms for cross-context reasoning of the user models, which can be applied for the context-aware per-sonalization. The reasoning augments the sparse user models by inferring the missing information from other context...