TITLE: Reusing Mathematical Models in ASCEND
AUTHORS: Krishnan, R., Piela, P., and Westerberg, A.
PUBLICATION: Recent Developments in Decision Support Systems, C. W. 
Holsapple and A. B. Whinston (eds.). Proceedings of the NATO ASI on 
Decision Support Systems
PUBLISHER: Springer-Verlag,  in cooperation with NATO Scientific Affairs 
Division
DATE: 1993
ABSTRACT: We believe model reuse to be an important mechanism by which
the productivity of the modeling process can be improved. In this
paper we describe the features that promote reuse in a mathematical
modeling environment called ASCEND (Advanced System for Computations
in Engineering Design). Essentially, our approach has been to identify
the operations (e.g., refinement, integration) used to reuse models
and to provide a collection of operators that reduce the effort
required by modelers to perform them. We have implemented this
approach in ASCEND using a) a strongly typed modeling language that
accommodates a structured model building approach, b) a small
collection of operators that employ type inference to support
operations such as integration that modelers perform to reuse models,
and c) "ports" that enable modelers to work with models using the
level of information hiding (e.g., black box, gray box) required to
accomplish reuse. Using these features we were able to address the
benchmark model reuse problems that have appeared in the literature in
a straightforward manner.