Management of conflict for preliminary engineering design tasks

Abstract

Much of preliminary engineering design is a constraint-driven non-monotonic exploration process. Initial decisions are made when information is incomplete and many goals are contradictory. Such conditions are present regardless of whether one or several designers contribute to designs. This paper presents an approach for supporting decisions in situations of incomplete and conflicting knowledge. In particular, we use assumptions and conflict management to achieve efficient search in contexts where little reliable information exists. A knowledge representation, containing a semantic differentiation between two types of assumptions, is used within a computational model based on the dynamic constraint satisfaction paradigm. Conflict management strategies consist of three generic mechanisms adapted to the type of constraints involved. These strategies may be refined through consideration of variable importance, context, and design inertia.

Applied Interval Analysis

“…Later, CSPs were extended to continuous domains (subsets of lR or intervals) (Cleary, 1987;Davis, 1987;Hyvonen, 1992;Lhomme, 1993;Benhamou et al, 1994;Haroud et al, 1995;Sam-Haroud, 1995;Sam-Haroud and Faltings, 1996;Deville et al, 1997;van Hentenryck et al, 1998;Lottaz et al, 1998). Most of the algorithms presented in these papers use consistency techniques such as those described below to find an outer approximation of the set § of all solutions of H. The main advantage of these techniques is that they yield a guaranteed enclosure of § with a complexity that can be kept polynomial in time and space.…”