Service adaptation is one of the main research subjects in Ubiquitous Computing. Dynamic service adaptation, at runtime, is necessary for services that cannot be stopped (banking, airport, etc.). The classical approaches for dynamic adaptation require predicting all service and context states in order to specify service and context-specific adaptation policies. This prediction may lead to a combinatorial explosion. The aim of this research is to create a service and context-independent adaptation mechanism. Our proposal is based on a service-context model that is causally connected with the service and context, in a model@run.time paradigm. A closed-loop control principle is used for the adaptation mechanism. We introduce an equivalent for the error that is expressed by the notion of service-context distance. This distance represents a measure of how adequate is a service to its context. This distance is computed by some generic, reusable components. The adaptation algorithm that minimizes this distance is also service and context-independent.
The aim of the paper is to present a fuzzy method for the optimization of the CMOS operational amplifier design. Our method uses f u z v sytems or fuzzy sets in all stages involved in the optimization process. In order to reduce the time spent for circuit performance evaluation, we use fuzzy system to model each circuit performance. The optimization problem formulation is accomplished in a flexible manner using fuzzy sets to delne fuzzy optimization objectives. We use qualitative design knowledge to modi& the design parameters in each iteration. This is done using a fuzzy system for each parameter, AJer introducing our fizzy optimization method we design a basic two-stage CMOS operational amplijier.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.