SIMULATION: Transactions of The Society for Modeling and Simulation International

Pratt, Charles A.

doi: 10.1177/003754978003500601pmid: N/A

Many of us were delighted to hear of the award of the 1980 Nobel Prize in economics to Dr. Lawrence Klein of the University of Pennsylvania. He was presented this award as ''the leading research worker within the field of the economic science which deals with the construction and analysis of empirical models of business fluctuations." Since Dr. Klein is a long-time simulationist, I thought we should hear from him and contacted him by phone for the following interview.

McLeod, John; McLeod, Suzette

doi: 10.1177/003754978003500608pmid: N/A

Uyeno, Dean H.; Vaessen, Willem

doi: 10.1177/003754978003500602pmid: N/A

This paper describes a set of procedures that can be used to construct discrete-event simulation models in PASCAL. The set of procedures is called PASSIM for PASCAL-based SIMulation The approach combines scheduler and entity concepts from GPSS with pointer- based data structures and control structures from PASCAL. The procedures employ only standard PASCAL statements to ensure portability.

Chu, Jean; Ermolowich, Hichael

doi: 10.1177/003754978003500603pmid: N/A

We have used computer simulation to help determine the optimum size of a silo for coal produced from the McInnes Mine in Pike County, Kentucky. The silo is used to store coal that is waiting to be cleaned. Previous experience suggested a silo capacity of 6000 tons. However, because of the complexity of the operation, we undertook a further study to evaluate the proposed size.We used computer simulation to model the system and estimate the amount of lost coal production for different silo capacities. Based on the simulation results, we recommended a silo capacity of 7 500 tons to eliminate a potential bottleneck which could cause a loss of production.The total study took two weeks, including model development and preparation of the report for model uses. The cost, including man-hour charges and computer charges, was approximately three thousand dollars.We expect this study to provide savings of 1.5 million dollars, the difference in total life-cycle costs (including the cost of lost production and the initial investment) between the two proposed silo sizes. This cost/benefit ratio demonstrates the usefulness of computer simulation as a tool to solve real problems.

Mamrak, Sandra A.; Amer, Paul D.

doi: 10.1177/003754978003500604pmid: N/A

In simulation studies, means, percentiles, or pro portions are often used to summarize measurements of system performance. We describe procedures for estimating confidence intervals for each of these three statistics. We conclude that proportions are generally best suited to computer simulation studies. We present empirical data that clarifies the proce dures and justifies the recommendation of proportions.

Abrahamson, Gunnar

doi: 10.1177/003754978003500606pmid: N/A

Cameron, William D.

doi: 10.1177/003754978003500605pmid: N/A

Newman, Richard A.

doi: 10.1177/003754978003500607pmid: N/A