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SIMA Reference Architecture Part I: Activity Models



Edward J. Barkmeyer Jr., Neil Christopher, Shaw C. Feng, James E. Fowler, Simon P. Frechette, Albert T. Jones, Kevin K. Jurrens, Charles R. McLean, Mike Pratt, Harry A. Scott, M. K. Senehi, Ram D. Sriram, Evan K. Wallace


This report describes the activities and information flows inherent in the product realization process for discrete electro-mechanical parts and products. That is, it describes the technical functions which must be performed to take a part/product from conception through production. Because of the spectrum of parts and processes involved, the elaboration of these activities and flows is at a fairly high level of abstraction, using IDEF0 as the formal modelling language.

The purpose of this report is to provide the basis for a reference architecture, describing the functions and relationships of software systems in the product realization process, and the nature of the information interfaces needed among those systems. It is intended that the continuation of the work will produce a report defining the systems architecture (Part 2) and many separate reports defining particular information interfaces in detail. The goal of the work is to have some standard form of those interfaces specified and implemented by commercial manufacturing software products, so that such products will work together off-the-shelf, and thus the delivery of enhanced software capabilities to the manufacturing user may be significantly accelerated.

NIST Interagency/Internal Report (NISTIR) - 5939
Report Number


activity models, CIM architecture, CIM framework, manufacturing software, product realization process, software interfaces


Barkmeyer Jr., E. , Christopher, N. , Feng, S. , Fowler, J. , Frechette, S. , Jones, A. , Jurrens, K. , McLean, C. , Pratt, M. , Scott, H. , Senehi, M. , Sriram, R. and Wallace, E. (1987), SIMA Reference Architecture Part I: Activity Models, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed April 14, 2024)
Created June 30, 1987, Updated October 12, 2021