U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 5351 - 5375 of 7113

Distributing UTC(NIST) to Industrial Time and Frequency Users

November 18, 2009
Author(s)
Michael A. Lombardi, Victor S. Zhang
The National Institute of Standards and Technology (NIST) maintains one of the world s most accurate and stable time scales, UTC(NIST), as well as the NIST-F1 cesium fountain, the primary frequency standard for the United States. These standards are

Niobium-silicide Junction technology for superconducting digital electronics

June 15, 2009
Author(s)
David I. Olaya, Paul D. Dresselhaus, Samuel P. Benz
Digital superconducting electronics (SCE), which allows for very low power consumption and fast switching speeds, are a promising technology to deliver ultra-high performance computation. Currently, the preferred technology for junctions in SCE consists of

Modelling of Thermodynamics and Diffusion in Multicomponent Systems

April 1, 2009
Author(s)
Ursula R. Kattner, Carelyn E. Campbell
The availability of reliable materials data is key to the successful design of materials and manufacturing processes. Commercial alloys rarely consist of only two or three elements, but rather may contain a large number of elements for which the needed

Questioning the Linear Relationship Between Doorway Width and Achievable Flow Rate

January 1, 2009
Author(s)
Steve M. Gwynne, Jessica Kratchman, Erica D. Kuligowski, James A. Milke
This paper suggests that the currently assumed linear relationship between exit width and achievable flow is a simplification that may lead to an overly optimistic view of the achievable flow rates. Analyzed data is presented from several sources in order

Atomic Data for Lighting Applications

October 16, 2008
Author(s)
Gillian Nave, Craig J. Sansonetti, Joseph Reader
A major objective of our research program is the observation of spectra of rare earth elements in support of our program of atomic data measurements for lighting applications. Three years ago, NIST acquired a high-resolution Fourier transform spectrometer

Calculation of Hydrogenic Bethe Logarithms for Rydberg States

October 16, 2008
Author(s)
U Jentschura, Peter J. Mohr
We describe the calculation of hydrogenic (one-loop) Bethe logarithms for all states with principal quantum numbers n 200. While the calculation of the Bethe logarithm is a rather easy computational problem involving only the nonrelativistic a (Schr'dinger

Non-Contact Temperature Measurements of Micro-Scale Phenomena

October 16, 2008
Author(s)
Howard W. Yoon
Imaging trying to make temprature measurements in a spatial region equal to the edge of a printer paper or within the diameter of a strand of hair. The accurate computer modeling of the machining process requires measurements of the thermodynamic

Thermodynamic Property Values for Enzyme-catalyzed Reactions

August 20, 2008
Author(s)
Robert N. Goldberg
This chapter deals with how one can obtain values of thermodynamic properties specifically the apparent equilibrium constant K, the standard molar transformed Gibbs energy change rG, and the standard molar transformed enthalpy change rH for

A Step Towards CO2-Neutral Aviation

November 20, 2007
Author(s)
Andreja Brankovic, Robert C. Ryder, Robert C. Hendricks, Marcia L. Huber
An approximation method for evaluation of the caloric equations used in combustion chemistry simulations is described. The method is applied to generate the specific heat, static enthalpy, and Gibb's free energy equations for fuel mixtures of interest to

Interpolation Procedures for Database-Assisted Design

July 1, 2007
Author(s)
Joseph A. Main
Database-assisted design (DAD) is a methodology of designing structures for wind loads that makes direct use of pressure time series from wind tunnel tests. This paper presents interpolation procedures that enable application of the DAD approach for cases

Visualization and Modeling of Smoke Transport Over Landscape Scales

May 1, 2007
Author(s)
Glenn P. Forney, William E. Mell
Computational tools have been developed at the National Institute of Standards and Technology (NIST) for modeling fire spread and smoke transport. These tools have been adapted to address fire scenarios that occur in the wildland urban interface (WUI) over

TheoH and Allan Deviation as Power-Law Noise Estimators

February 1, 2007
Author(s)
Jennifer A. Taylor, David A. Howe
A spectral interpretation using the frequency response of the Allan Variance is used to determine slopes of f α noise, commonly called ''power-law noise.'' This paper shows that TheoH provides significantly better determination of f α noise slopes at long

Unique File Identification in the National Software Reference Library

October 24, 2006
Author(s)
Steven L. Mead
The National Software Reference Library (NSRL) provides a repository of known software, file profiles, and file signatures for use by law enforcement and other organizations involved with computer forensic investigations. This paper examines whether the

4K Cryocooler Implementation of a DC Programmable Voltage Standard

June 1, 2003
Author(s)
Charles J. Burroughs, Robert J. Webber, Paul Dresselhaus, Samuel Benz
NIST and Hypres, Inc. have been collaborating to develop a 1 Volt DC programmable Josephson voltage standard (PJVS) that operates on a closed-cycle refrigerator. The goal of this work is to construct a platform that will allow the chip to work at 4 K

Manufacturing Interoperability

May 1, 2003
Author(s)
Steven R. Ray, Albert T. Jones
As manufacturing and commerce become ever more global in nature, companies are increasingly dependent upon the efficient and effective exchange of information with their partners, wherever they may be. Leading manufacturers rely upon computers to perform

Metallurgical Analysis of Wrought Iron From the RMS Titanic

April 1, 2003
Author(s)
J J. Hooper, Timothy J. Foecke, L Graham, Timothy P. Weihs
The discovery of the RMS Titanic has led to a number of scientific studies, one of which addresses the role that structural materials played in the sinking of the ship. Early studies focused on the quality of the hull steel as a contributing role to the

Policy Expression and Enforcement for Handheld Devices

April 1, 2003
Author(s)
Wayne Jansen, Tom T. Karygiannis, Vladimir Korolev, Serban I. Gavrila, Michaela Iorga
The use of mobile handheld devices, such as Personal Digital Assistants (PDAs) and tablet computers, within the workplace is expanding rapidly. These devices are no longer viewed as coveted gadgets for early technology adopters, but instead have become

Statistical Uncertainty Analysis of Key Comparison CCEM-K2

April 1, 2003
Author(s)
Nien F. Zhang, N Sedransk, Dean G. Jarrett
The details of a statistical uncertainty analysis applied to key comparison CCEM-K2 are reported. The analysis presented here provides an approach for addressing known correlations which have been of concern in reporting key comparison results

Literature Review on Enclosure of Elevator Lobbies

March 1, 2003
Author(s)
D W. Stroup
A literature survey was conducted to explore the need and appropriate systems for protecting elevator lobbies from smoke migration. The focus is on smoke spread through elevator shafts and lobbies, building occupant and fire fighter use of elevators during
Displaying 5351 - 5375 of 7113
Was this page helpful?