Um Mecanismo de Adaptação para Aplicações Tempo Real Baseado em Computação Imprecisa e Reflexão Computacional
Abstract
Many applications with real-time requirements are disseminated through the Internet as Java applets or Active-X components. For example, applications that deal with audio and video, tools for cooperative work and video games. It is difficult to satisfy timing requirements since these applications must execute on very different execution environments (processors and operating systems), with different levels of performance and utilization. An important problem is how to design software components so they present an acceptable performance even when executing on different environments. One technique to provide adaptation is the imprecise computation, since it introduces flexibility into the execution time of tasks. Also, computational reflection facilitates the implementation of imprecise computation by separating functional aspects from controlling aspects that are responsible for the adaptation. The purpose of this paper is to show how variations of imprecise computation, implemented by using refletion, can be used to allow the adaptation of real-time applications to different execution environments in the context of the Internet. The programming model RTR is used to ilustrate how this adaptation may be programmed.
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