Joshua Lubell

Conformance checking of PMI representation in CAD model STEP data exchange files

Recommended practices supplement data exchange standards by providing common implementation guidance associated with specific requirements. ISO 10303 (STEP) product data exchange files that conform to recommended practices ensure interoperability between computer-aided design (CAD) systems and with downstream applications such as manufacturing and inspection. Correct implementation of product and manufacturing information (PMI)-annotations associated with a CAD models edges and faces such as geometric tolerances, dimensional tolerances, and datum features-in CAD authoring systems and translators is essential for interoperability. This paper discusses an approach implemented in a software tool for checking the conformance of STEP files to the recommended practice for PMI representation. Display Omitted Geometric and dimensional tolerances (PMI) are represented in STEP files.Correct implementation of PMI ensures interoperability with downstream applications.A software tool has been developed for conformance checking of PMI in STEP files.

Enabling Smart Manufacturing Technologies for Decision-Making Support

Smart manufacturing combines advanced manufacturing capabilities and digital technologies throughout the product lifecycle. These technologies can provide decision-making support to manufacturers through improved monitoring, analysis, modeling, and simulation that generate more and better intelligence about manufacturing systems. However, challenges and barriers have impeded the adoption of smart manufacturing technologies. To begin to address this need, this paper defines requirements for data-driven decision making in manufacturing based on a generalized description of decision making. Using these requirements, we then focus on identifying key barriers that prevent the development and use of data-driven decision making in industry as well as examples of technologies and standards that have the potential to overcome these barriers. The goal of this research is to promote a common understanding among the manufacturing community that can enable standardization efforts and innovation needed to continue adoption and use of smart manufacturing technologies.

Model-Based Enterprise Summit Report

Abstract : This report summarizes the presentations, discussions, and recommendations from the Model-Based Enterprise Summit held at the National Institute of Standards and Technology in December of 2012. The purpose of the Summit was to identify challenges, research, implementation issues, and lessons learned in manufacturing and quality assurance where a digital three-dimensional (3D) model serves as the authoritative information source for all activities in a product s lifecycle. The report includes an overview of model-based engineering, technical challenges, summaries of the presentations given at the workshop, and conclusions that emerged from the presentations and discussions.

Evaluating reasoning systems

A review of the literature on evaluating reasoning systems reveals that it is a very broad area with wide variation in depth and breadth of research on metrics and tests. This is the second of a two-part series that begins to bring order to the area by categorizing reasoning systems according to their capabilities. These can be used as a basis for evaluating and testing reasoning systems claiming to be in each category. Capabilities are analyzed along the dimensions of representation languages and inference. The first part introduces information metrology, model theory, and inference to facilitate understanding of the reasoning categories presented. It also groups representation languages by their relation to first-order logic, and model-theoretic properties, such as soundness and completeness. This part examines inference procedures, dividing them into deduction, induction, abduction, and analogical reasoning. It explains the subcategories and characteristics of each, and concludes with recommendations for future work.

Towards a Reference Architecture for Archival Systems: Use Case With Product Data

Long-term preservation of product data is imperative for many organizations. A product data archive should be designed to ensure information accessibility and understanding over time. Approaches, such as the Open Archival Information System Reference Model (OAIS RM) and the Audit and Certification of Trustworthy Digital Repositories (ACTDR), provide a framework for conceptually describing and evaluating archives. These approaches are generic and do not focus on particular contexts or content types such as product data. Moreover, these approaches offer no guidance on how to formally and comprehensively describe archival systems. Such descriptions should include the business activities that a product data archive has to support and the systems that interact with the archive. Enterprise architecture provides a means to describe systems in their potentially complex environments. This paper proposes a holistic approach to formally describe the architecture and the environment of archival systems. This approach relies on the formal representation of the preservation terminology, including OAIS concepts, using the Department of Defense Architecture Framework (DoDAF). The approach covers the various interactions of other business functions with the archive and the information models necessary to ensure preservation and accessibility of product data. This approach is a step towards a reference architecture for the formal description of archival systems. To demonstrate the approach, we formally describe the ingest of product data related to a ship. The resulting description uses the preservation terminology defined in the OAIS Reference Model. It facilitates the understanding of how the preservation solution is actually implemented and provides evidence that the solution is able to preserve product data and make it accessible.

Toward a Reference Architecture for Archival Systems

Long-term preservation of product data is imperative for many organizations. A product data archive should be designed to ensure information accessibility and understanding over time. Approaches such as the Open Archival Information System (OAIS) Reference Model and the Audit and Certification of Trustworthy Digital Repositories (ACTDR) provide a framework for conceptually describing and evaluating archives. These approaches are generic and do not focus on particular contexts or content types. Enterprise architecture provides a way to describe systems in their potentially complex environments.

The express Web server: a user interface for standards development

2. ABSTRACT The EXPRESS Web Server is a World Wide Web interface for standards developers creating specifications for STEP, the STandard for the Exchange of Product model data (officially ISO 10303). The Server enables users to run applications needed to build and populate EXPRESS specifications using a Web browser and without having to install and configure the applications locally. The Server also provides standards development teams with an infrastructure for collaboration. This paper describes the Server’s user interface, specifies how the Server’s architecture addresses several design challenges, and discusses the impact newly-emerging web technologies might have on future enhancements.

Architectures in an XML world

XML (Extensible Markup Language) developers have at their disposal a variety of tools for achieving schema reuse. An often-overlooked reuse method is the specification of architectures for creating and processing data. Experience with APEX (Architectural Processor Employing XSLT), an architecture processing tool implemented using XSLT (Extensible Style Language Transformations), demonstrates that architectures can fulfill a role not well served by alternative approaches to reuse.

CHALLENGES TO AUTOMATING SECURITY CONFIGURATION CHECKLISTS IN MANUFACTURING ENVIRONMENTS

Information technology is essential to today’s manufacturing systems, but it makes them more vulnerable to cyber security threats than ever before. This chapter discusses the challenges to developing automatable configuration checklists for manufacturing environments using the Security Content Automation Protocol (SCAP) family of standards. Increased use of SCAP in manufacturing environments could reduce security vulnerabilities and the likelihood of damaging cyber attacks on manufacturing systems. However, complex relationships and dependencies within and between checklist rules, checking instructions and software result in platform fragmentation. Platform fragmentation makes it difficult to reuse or repurpose existing SCAP-expressed checklist content. Recent research and technological developments can be leveraged to yield potentially promising approaches for mitigating platform fragmentation and improving reuse.

Flat Versus Hierarchical Information Models in PLM Standardization Frameworks

Smart manufacturing requires digital product data to be shared and exchanged among numerous engineering applications and information systems. But no single product data standard can satisfy every integration scenario. Customizable standardization frameworks for Product Lifecycle Management (PLM) attempt to address this problem by allowing users to add new information structures to an existing data model in a controlled manner. A PLM information model may be either flat or hierarchical. We discuss two approaches. One is based on ISO 10303-239 as an exemplar for customizing flat models. The other is based on Open Application Group Integration Specification (OAGIS) as an exemplar for customizing hierarchical models. We evaluate the two approaches and observe that the type of model strongly influences how well the PLM standardization framework meets each evaluation criterion, and that the best choice is use-case dependent.