Adaptive Technology and Its Applications

INTRODUCTION Before the advent of software engineering, the lack of memory space in computers and the absence of established programming methodologies led early programmers to use self-modification as a regular coding strategy. Although unavoidable and valuable for that class of software, solutions using self-modification proved inadequate while programs grew in size and complexity, and security and reliability became major requirements. Software engineering, in the 70's, almost led to the vanishing of self-modifying software, whose occurrence was afterwards limited to small low-level machine-language programs with very special requirements. Nevertheless, recent research developed in this area, and the modern needs for powerful and effective ways to represent and handle complex phenomena in high-technology computers are leading self-modification to be considered again as an implementation choice in several situations. Artificial intelligence strongly contributed for this scenario by developing and applying non-con-In this publication, another alternative is proposed for developing Artificial Intelligence applications: the use of adaptive devices, a special class of abstractions whose practical application in the solution of current problems is called Adap-tive Technology. The behavior of adaptive devices is defined by a dynamic set of rules. In this case, knowledge may be represented, stored and handled within that set of rules by adding and removing rules that represent the addition or elimination of the information they represent. Because of the explicit way adopted for representing and acquiring knowledge, adaptiv-ity provides a very simple abstraction for the implementation of artificial learning mechanisms: knowledge may be comfortably gathered by inserting and removing rules, and handled by tracking the evolution of the set of rules and by interpreting the collected information as the representation of the knowledge encoded in the rule set. This article provides concepts and foundations on adaptivity and adaptive technology, gives a general formulation for adaptive abstractions in use and indicates their main applications. It shows how rule-driven devices may turn into adaptive devices to be applied in learning systems modeling, and introduces a recently formulated kind of adaptive abstractions having adaptive sub-jacent devices. This novel feature may be valuable for implementing meta-learning, since it enables adaptive devices to change dynamically the way they modify their own set of defining rules. A significant amount of information concerning adaptivity and related subjects may be found at the (LTA Web site).