Simulation Modeling Methodology

in the Wonderfully Webbed World

While modeling methodology has been with us since the inception of simulation, it remained indistinguishable from programming throughout the first two decades. Neverthelss, a few early researchers abstracted beyond the executable form to search for more significant semantic revelations. Lackner and Kribs (1964) and Kiviat (1967) are prominent examples, but Tocher's (1966) wheel charts to assist in model specification and the IFIP proceedings on simulation programming languages (Buxton 1968) show that interest was widespread. Efforts to derive a theory of simulation (Zeigler 1976) generated interest in model representation in the 1970s. The latter part of the decade ushered in the first specific focus on modeling methodology (model life cycle, model specification languages, the DELTA project) (Nance 1979). With the 1980s came the vision of model development environments (Nance 1983) that are now a commercial reality. Is the subject of this panel session presaging the next major transition in simulation model development?

Modeling Methodology

Since ``methodology'' is both over-used and misused, a definitional explanation in this context is appropriate. Methodology, following the view of Arthur et al. (1986, p.4), should:

organize and structure the tasks comprising the effort to achieve global objectives,
include methods and techniques for accomplishing individual tasks (within the framework of global objectives), and
prescribe an in which certain classes of decisions are made and the ways of making those decisions leading to desired objectives.

Key in the attainment of the objectives are the principles that form the foundational support of a methodology.

Influence of the Web

If the world wide web is to effect major changes in modeling methodology, then it must alter or abolish existing principles or introduce new principles. At this juncture the capability of the web to influence the technology of model building, model execution and model sharing is clear, and the degree of change appears significant. However, that the potential for influence extends into the principles - the foundational core - is less apparent.

References

Arthur, J.D., R.E. Nance and S.M. Henry. 1986. ``A Procedural Approach to Evaluating Software Development Methodologies and Associated Products.'' SRC-87-007, Systems Research Center, Virginia Tech, Blacksburg, VA.
Buxton, J.(ed). 1968. Proceedings of the IFIP Working Conference on Simulation Programming Languages, North-Holland.
Kiviat, P.J. 1967. ``Digital Computer Simulation: Modeling Concepts.'' RAND Memo RM-5883-PR, Santa Monica, CA.
Lackner, M.R. and P. Kribs. 1964. ``Introduction to a Calculus of Change.'' System Development Corp., TM-1750/000/01.
Nance, R.E. 1979. ``Model Representation in Discrete Event Simulation: Prospects for Developing Documentation Standards.'' In Current Issues in Computer Simulation, N. Adam and A. Dogramaci (eds), Academic Press, 83-97.
Nance, R.E. 1983. ``A Tutorial View of Simulation Model Development.'' In: Proceedings of the 1983 Winter Simulation Conference, (Arlington,VA, Dec 12-14). IEEE, Piscataway, NJ, 325-331.
Tocher, K.D.T. 1966. ``Some Techniques of Model Building.'' In: Proceedings, IBM Scientific Symposium on Simulation Models and Gaming, pp. 119-155, White Plains, NY.
Zeigler, B.P. 1976. Theory of Modelling and Simulation, Wiley, New York.

Biography

Richard E. Nance is the RADM John Adolphus Dahlgren Professor of Computer Science and the Director of the Systems Research Center at Virginia Tech (VPI&SU). Dr. Nance is also Chairman of the Board of Orca Computer, Inc. He received B.S. and M.S. degrees from N.C. State University in 1962 and 1966, and the Ph.D. degree from Purdue University in 1968. He has served on the faculties of Southern Methodist University and Virginia Tech, where he was department head of Computer Science, 1973-1979. He held a distinguished visiting honors professorship at the University of Central Florida for the spring semester, 1997. Dr. Nance has held research appointments at the Naval Surface Weapons Center and at the Imperial College of Science and Technology (UK). Within ACM, he has chaired two special interest groups: Information Retrieval (SIGIR), 1970-71 and Simulation (SIGSIM), 1983-85. He has served as Chair of the External Activities Board and several ACM committees. He is the US representative to IFIP TC7. The author of over 100 papers on discrete event simulation, performance modeling and evaluation, computer networks, and software engineering, Dr. Nance has served on the Editorial Panel of Communications of the ACM for research contributions in simulation and statistical computing, 1985-89, as Area Editor for Computational Structures and Techniques of Operations Research, 1978-82, and as Department Editor for Simulation, Automation, and Information Systems of IIE Transactions, 1976-81. He served as Area Editor for Simulation, 1987-89 and as a member of the Advisory Board, 1989-92, for the ORSA Journal on Computing. Dr. Nance was the founding Editor-in-Chief of the ACM Transactions on Modeling and Computer Simulation, 1990-1995. He served as Program Chair for the 1990 Winter Simulation Conference. Dr. Nance received a Distinguished Service Award from the TIMS College on Simulation in 1987. In 1995 he was honored by an award for "Distingusished Service to SIGSIM and the Simulation Community" by the ACM Special Interest Group on Simulation. He was named an ACM Fellow in 1996. He is a member of Sigma Xi, Alpha Pi Mu, Upsilon Pi Epsilon, ACM, IIE, and INFORMS. (Address: Systems Research Center and Department of Computer Science, Virginia Polytechnic Institute & State University, Blacksburg, Virginia 24061, E-mail: nance@vt.edu)

Web-Based Simulation: Whither We Wander?

Animated GIF courtesy of Web GraFX-FX