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Error sources in gage block mechanical comparisons can range from classical textbook examples (thermal gradients, correct temperature value, and correct master
The National Institute of Standards and Technology (NIST) has been developing the \Real-Time Control Sys- tems (RCS)" software for more than two decades and us-
This discussion paper proposes that development of formalized standards for the rapid prototyping (RP) industry will help enable the continued growth and
A variety of different kinds of photomask critical dimension (CD) metrology tools are available today to help meet current and future metrology challenges
Theodore D. Doiron, Dennis S. Everett, Bryon S. Faust, Eric S. Stanfield, John R. Stoup
The current definition of length of a gage block is a very clever attempt to evade the systematic errors associated with the wringing layer thickness and
The 4-D/Real-Time Control Systems Architecture (4- D/RCS) defines a hierarchical decomposition for intelligent systems, with corresponding command and control
This paper presents a method for determining the location of geometric elements that compose the external features of referencing fixtures. Since in most
This paper concerns the informational requirements of layered manufacturing (LM). The most common industrial use of LM today is for rapid prototyping, but we
This paper presents a novel design for a practical tactilesensing mechanical fixture. The fixture consists of two tactilesensing surfaces, a cylindrical surface
This paper presents a case study in the use of the Internet as a medium for exchange of information and delivery of computer-aided design and computer-aided
One of the most elusive measurement elements in gage block interferometry is the correction for the phase change on reflection. Techniques used to quantify this
We have found conceptual problems with the far-field formula 1 for mode field diameter First, the formulation is incomplete in that it ignores the obliquity
We have developed a biased perturbation method for calculating the index profiles of single-mode fibers from either near-field or far-field data. Unlike other
Multimode fiber bandwidth is currently measured using an overfilled launch condition. Such a launch is achieved by uniformly exciting the core and launching
Paul A. Williams, A. J. Barlow, C. Mackechnie, John B. Schlager
A common characteristic of current methods for measuring polarization-mode dispersion (PMD) is the need for a broad optical bandwidth. With the increasing use
Gale A. Holmes, R C. Peterson, Donald L. Hunston, Walter G. McDonough
Most ductile polymers exhibit nonlinear viscoelastic behavior above 1% strain. In structural applications where matrix deformation may play and important role
Two Josephson Array Voltage Standard Systems using different calibration algorithms are operated at the National Institute of Standards and Technology. A manual
Sanford P. Ressler, Afzal A. Godil, Quandou (. Wang, G S. Seidman
This paper describes several methods for using the Virtual Reality Modeling Language (VRML) as the visualization integration tech-nology for manufacturing
Robert C. Hagwood, Raghu N. Kacker, James H. Yen, D L. Banks, Lynne S. Rosenthal, Leonard J. Gallagher, Paul E. Black
A conformance test is a software assurance test that is applied in order to determine if specification requirements of the software are being met. It is a time
Daniel E. Kelleher, William C. Martin, Wolfgang L. Wiese, J Sugar, Craig J. Sansonetti, Jeffrey R. Fuhr, Joseph Reader, Arlene Musgrove, Karen J. Olsen, Peter J. Mohr, G R. Dalton
Sam R. Coriell, B T. Murray, A A. Chernov, Geoffrey B. McFadden
We treat the effect of shear flows on the morphological stability of a crystal growing from solution by a step mechanism at a given constant velocity. We carry
A large class of distributed testing, control and collaborative applications are reactive or event driven in nature. Such applications can be structured as a
Prior work has shown that thin filament pyrometry (TFP) is a powerful approach for making highly precise, spatially and temporally resolved line measurements of
An apparatus was developed for testing the extinction efficiency of a solid powder in a coflowing non-premixed flame. Extinction measurements were performed by
The Minerals Management Service (MMS), in cooperation with several oil and gas companies, installed a seismometer network on the ocean floor in the Santa
Fiber-reinforced polymer composites are increasingly used in offshore and civil engineering structures. In these applications, composite materials are often