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FED-X: The NIST Express Translator



Steve Clark, Donald E. Libes


The Product Data Exchange using STEP (PDES) is an emerging standard for the exchange of product information among various manufacturing applications. PDES includes an information model written in the Express language; other PDES-related information models are also written in Express. The National PDES Testbed at NIST has developed software to manipulate and translate Express models. This software consists of an in-memory working form and an associated Express language parser, Fed-X. The design and capabilities of Fed- X and the Express Working Form are discussed.
NIST Interagency/Internal Report (NISTIR) - 4822
Report Number


Express, information models, manufacturing applications, PDES, product information, STEP


Clark, S. and Libes, D. (1992), FED-X: The NIST Express Translator, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed April 17, 2024)
Created September 30, 1992, Updated October 12, 2021