Object-oriented simulation: where do we go from here?

ABSTRACT

Object-oriented simulation provides a rich and lucid paradigm for building computerized models of real-world phenomena. Its strength lies in its ability to represent objects and their behaviors and interactions in a cogent form that can be designed, evolved and comprehended by domain experts as well as system analysts. It allows encapsulating objects (to hide irrelevant details of their implementation) and viewing the behavior of a model at a meaningful level. It represents special relations among objects (class-subclass hierarchies) and provides “inheritance” of attributes and behaviors along with limited taxonomic inference over these relations. It represents interactions among objects by “messages” sent between them, which provides a natural way of modeling many interactions. Despite these achievements, however, there remain several largely unexplored areas of need, requiring advances in the power and flexibility of modeling, in the representation of knowledge, in the integration of different modeling paradigms, and in the comprehensibility, scalability and reusability of models. The Knowledge-Based Simulation project at Rand is working in several of these areas. In this paper, we will elaborate the existing limitations of object-oriented simulation and discuss some of the ways we believe the paradigm can be extended to surmount these limitations.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.6 SIMULATION AND MODELING

Additional Classification:
  D. Software
  D.1 PROGRAMMING TECHNIQUES

General Terms:
Design, Performance, Theory