The STEPml "library of XML specifications" has been designed as a publication forum and education center for XML-based STEP product data schemas governing process integration, supply chain management, collaborative engineering, analysis, manufacturing, and customer support. STEPml is sponsored by PDES, Inc., an international industry/government consortium. The STEPml initiative is important because it exemplifies the growing interest in mapping STEP/EXPRESS to XML: STEP's EXPRESS schema language has rich facilities for specifying semantic constraints for data modeling purposes, whereas SGML/XML does not. In February 2001, STEPml published the first three in a series of planned resources which combine the "semantically rich, international standard data models from STEP (ISO 10303) with the widespread infrastructure of XML and the Web. STEP is an international standard for the representation of product data; STEP models are documented using EXPRESS, a formal object-flavored language that has a robust constraint definition capability. STEPml takes the data models from STEP and publishes them as XML specifications; the STEPml XML specifications are automatically generated from STEP schemas. Resources published to date include a STEPml XML DTD for the STEP PDM Schema, a STEPml Product Identification and Classification Specification, and a technical overview of the STEP Object Serialization Early Binding (OSEB). STEPml is one of several STEP-XML initiatives now gathering momentum. Several bindings have been designed for the mapping of semantically-rich EXPRESS data models to XML, and are documented in ISO's 306-page Proposed Draft Technical Specification Product Data Representation and Exchange. Implementation Methods: XML Representation of EXPRESS Schemas and Data [ISO TC184/SC4/WG11 N140. ISO/PDTS 10303-28:2000(E)]. The ISO/SC4 10303-25 project is also developing an EXPRESS to OMG XMI binding.

"STEPml is sponsored by PDES Inc. PDES, Inc., an international industry/government consortium, has been a major contributor to the development of the international standard for product data, STEP, for over 10 years. [Participants include:] Boeing, BAE SYSTEMS, Delphi Automotive Systems, Electric Boat, Ford, General Motors, IBM, Lockheed Martin, MSC Software, NASA, NIST, Northrop Grumman, PTC, Rockwell, Rolls-Royce, SDRC, Spatial, Theorem Solutions, United Technologies Corporation, and U.S. Army."

"STEPml Specification: Object Serialization Early Binding (OSEB) Overview." Informational resource provided in connection with the 'STEPml Product Identification and Classification Specification'. "The structure of the STEPml markup for product data was designed based on the object model found in programming languages such as Java and on object serialization patterns. It is called the Object Serialization Early Binding (OSEB). Because engineering data is not made up of simple hierarchies, the way books are made of chapters and chapters of paragraphs, the use of XML containment for engineering data is problematic. In a network of objects representing engineering data it is difficult or impossible to decide what should contain what in any deterministic manner. Recognizing this, the OSEB is designed to align with the network of objects rather than developing arbitrary or context-dependent rules for the use of XML containment. As Java is the programming language for the Web, a simple object model based on the Java language was chosen and the OSEB philosophy is to structure the markup so that it aligns with that simple object model and uses XML ID and IDREF extensively...