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The Process Specification Language (PSL) Overview and Version 1.0 Specification



Craig I. Schlenoff, Michael Gruninger, Florence Tissot, John Valois, Joshua Lubell, Jonathan W. Lee


In all types of communication, the ability to share information is often hindered because the meaning of information can be drastically affected by the context in which it is viewed and interpreted. This is especially true among manufacturing systems because of the growing complexity of manufacturing information and the increasing need to exchange this information among different manufacturing functions(e.g., process planning, scheduling, simulation, etc.). Different manufacturing functions may use different terms to mean the exact same concept or use the exact same term to mean very different concepts. Often, the loosely defined natural language definitions associated with the terms contain much ambiguity that doesn't make these differences evident and/or do not provide enough information to resolve the differences. A solution to this problem is the development of a taxonomy, or ontology, of manufacturing concepts and terms along with their respective formal and unambiguous definitions. The Process Specification Language(PSL)(Version 1.0) developed at the National Institute of Standards and Technology identifies, formally defines, and structures the semantic concepts intrinsic to the capture and exchange of discrete manufacturing process information.
NIST Interagency/Internal Report (NISTIR) - 6459
Report Number


interoperability, KIF, manufacturing process specification, ontology, PSL


Schlenoff, C. , Gruninger, M. , Tissot, F. , Valois, J. , Lubell, J. and Lee, J. (2000), The Process Specification Language (PSL) Overview and Version 1.0 Specification, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed May 20, 2024)


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Created January 31, 2000, Updated October 12, 2021