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Search Publications

NIST Authors in Bold

Displaying 56326 - 56350 of 74214

Implementing Role-Based Access Control Using Object Technology

December 1, 1995
Author(s)
John Barkley
With Role Based Access Control (RBAC), each role is associated with a set of operations which a user in that role may perform. The power of RBAC as an access control mechanism is the concept that an operation may theoretically be anything. This is

Line-Reflect-Match Calibrations with Nonideal Microstrip Standards

December 1, 1995
Author(s)
Dylan F. Williams, J. B. Schappacher
We apply a previously developed Line-Reflect-Match (LRM) calibration that compensates for the nonideal electrical behavior of the match standard to microstrip transmission lines and investigate impedance definitions, standard parasitics, and calibration

NIST Laboratory Program on Atomic Spectroscopic Data for Astronomy,

December 1, 1995
Author(s)
William C. Martin, G R. Dalton, Jeffrey R. Fuhr, Daniel E. Kelleher, Alexander Kramida, Peter J. Mohr, Arlene Musgrove, Joseph Reader, Edward B. Saloman, Craig J. Sansonetti, J Sugar, G G. Wiersma, Wolfgang L. Wiese, D Zucker, J Blaise, J-F Wyart, G Eichhorn, C S. Grant

The ADACS Implementation of the UTAP Architecture

December 1, 1995
Author(s)
Robert Russell, John L. Michaloski, Keith A. Stouffer
The Advanced Deburring and Chamfer System is robotic workcell designed to put precision chamfers on parts made with hard metals. The project was funded by the United States Navy so that the technology developed could be applied to their air defense systems

Two-Tier Multiline TRL for Calibration of Low-Cost Network Analyzers

December 1, 1995
Author(s)
Jeffrey A. Jargon, Roger Marks
We compare calibrations for use on three-sampler vector network analyzers (VNAs), which do not allow the direct applica­tion of some advanced error-correction schemes such as TRL (thru-reflect-line). Here we compare various alternatives, including an

Visualization of Surface Figure Using Zernike Polynomials

December 1, 1995
Author(s)
Christopher J. Evans, R E. Parks, P Sullivan, John S. Taylor
Commercial software in modern interferometers used in optical testing frequently fit the wave-front or surface-figure error to Zernike polynomials; typically 37 coefficients are provided. We provide visual representations of these data in a form that may

Stylus Technique for Direct Verification of Rockwell Diamond Indenters

November 23, 1995
Author(s)
Jun-Feng Song, F Rudder, Theodore V. Vorburger, J Smith
Based on a stylus technique, a microform calibration system was developed at NIST for the direct verification of Rockwell diamond indenters. The least-squares radius and profile deviations, cone angle and cone flank straightness, and the holder axis

Ultrasound Power Measurement Techniques at NIST

November 12, 1995
Author(s)
Steven E. Fick
Megahertz-frequency sound waves with submillimeter wavelengths are widely used to probe the interior regions of many types of structures. When human tissues are exposed to ultrasound for diagnostic or therapeutic purposes, the applied power levels must be

Blind Estimation of Tip Geometry from Noisy Images

November 2, 1995
Author(s)
John S. Villarrubia
Broadening of image features due to non-vanishing tip size is a well-known imaging artifact in scanned probe microscopy (SPM) topographs. This need not be a serious limitation for some types of metrology (e.g. pitch or height), but it is significant for
Displaying 56326 - 56350 of 74214
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