Context-aware systems are able to monitor and automatically adapt their operation accordingly to the execution context in which they are introduced. Component-based software engineering (CBSE) focuses on the development and reuse of self-contained software assets in order to achieve better productivity and quality. In order to store and retrieve components, CBSE employs component repository systems to provide components to the system developers. This paper presents an active component repository that is able to receive the current configuration from the context-aware system and compute the components and the new architecture that better fit the given context. Since the repository has a wide knowledge of available components, it can better decide which configuration is more suitable to the running system. The repository applies Fuzzy logic algorithm to evaluate the adequacy level of the components and GRASP algorithm to mount the new system architecture. In order to verify the feasibility of our approach, we use a digital TV middleware case study to achieve experimental results. 1. Introduction Pervasive computing is becoming increasingly popular, as introduced by Weiser [1], the term pervasive refers to the seamless integration of computer devices and software into the everyday life. Context-awareness adaptation is an important field of the pervasive computing area. Context-aware systems are able to monitor and automatically adapt their operation accordingly to the execution context in which they are introduced. Component-based software engineering (CBSE) [2, 3] focuses on the development and reuse of self-contained software assets in order to achieve better productivity [4] and quality as software systems are composed by previously developed components used (and tested) in other projects. In this approach, the software system is composed by self-contained components that explicitly declare their provided functionalities (provided interfaces), required functionalities (required interfaces), and also their execution context requirements. In addition to the advantages described previously, component-based software (CBS) may present other features like component update, functionality enhancement, and adaptability. If a CBS needs to be updated, only the specific component implementing the updated feature needs to be updated. Functionality enhancement is also facilitated since new components with new functionalities can be added and dynamically loaded into the system. Finally, adaptability can also be accomplished by configuring and/or replacing a component
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