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Unified Process Specification Language: Requirements for Modeling Process



Craig I. Schlenoff, Amy Knutilla, Steven R. Ray


A wide range of applications deal with the manipulation and expression of collections of activities. Examples include project management, workflow management, business process reengineering, product realization process modeling, manufacturing process planning, production scheduling, simulation, and Computer Aided Software Engineering, each of which is supported by some combination of graphical programming and control languages, Petri nets, PERT charts or other representation methodology. Each of these applications serves a specific audience and need, and focuses on particular aspects of a process. Nevertheless, much could be gained by sharing information among applications. One of the primary obstacles to such integration is the lack of any common representation of what is really the common underlying concept of process. The objective of the work described here is an investigation of the feasibility of a unifying specification of process which is applicable to all of the above applications, yet powerful and robust enough to meet each set of requirements. This document represents the results of the first phase of the work - that of researching the process representational requirements for design/manufacturing process life-cycle applications. These requirements are categorized into four categories; core, outer core, extensions, and application, which aided in describing the role of the requirements in the overall challenge of process representation.
NIST Interagency/Internal Report (NISTIR) - 5910
Report Number


process planning, process representation requirements, PSL, systems integration, unified process specification language


Schlenoff, C. , Knutilla, A. and Ray, S. (1996), Unified Process Specification Language: Requirements for Modeling Process, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed May 25, 2024)


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Created December 31, 1995, Updated October 12, 2021