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Process Specification Language: An Analysis of Existing Representations



Amy Knutilla, Craig I. Schlenoff, Steven R. Ray, Stephen T. Polyak, Austin Tate, S C. Cheah, Richard C. Anderson


The goal of the National Institute of Standards and Technology (NIST) Process Specification Language (PSL) project is to investigate and arrive at a neutral, unifying representation of process information to enable sharing of process data among manufacturing engineering and business applications. This paper focuses on the second phase of the project, the analysis of existing process representations to determine how well existing process representation methodologies support the requirements for specifying processes found in Phase One. This analysis provides an objective basis from which to develop a comprehensive language and promotes the leveraging of existing work. The paper includes descriptions and citations for twenty-nine methodologies used to represent process models. The appendix includes a set of tables that indicate the constructs and features used by twenty-six representational approaches to specifying process requirements identified in the first phase of the PSL project.
NIST Interagency/Internal Report (NISTIR) - 6160
Report Number


manufacturing, process methodologies, process ontologies, process planning, process specification, Process Specification Language, PSL, systems integration


Knutilla, A. , Schlenoff, C. , Ray, S. , Polyak, S. , Tate, A. , Cheah, S. and Anderson, R. (1998), Process Specification Language: An Analysis of Existing Representations, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 26, 2024)


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Created May 1, 1998, Updated November 10, 2018