Modeling knowledge-based anytime computation

dThis article describes a Knowledge-based Anytime Computation to design a r eal-time decision-making model. Such a computation combines the expressiven ess and flexibility of knowledge-based systems with the real-time advantage s of anytime algorithms. Anytime computation offers a simple means by which an intelligent system can trade off computation time for quality of result s. Previous attempts to develop knowledge-based anytime algorithms failed t o produce consistent, predictable improvement of quality over time. Without performance profiles, that describe the output quality as a function of ti me, it is difficult to exploit the flexibility of anytime algorithms. The m odel of knowledge-based anytime computation based on progressive reasoning presented here is based on a hierarchy of reasoning units that allow for gr adual improvement of decision quality in a predictable manner. The result i s an important step towards the application of knowledge-based systems in t ime-critical domains. (C) 1999 Elsevier Science Ltd. All rights reserved.