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 5726 - 5750 of 7113

Calibrating multiple microscopes with a smartphone

April 1, 2014
Author(s)
Peter Bajcsy, Mary C. Brady, Jacob Siegel
Summary: The iPhone liquid crystal displays allows efficient and accurate calibration of an inexpensive array of handheld microscopes for measuring microscopic dynamic events over a large field of view. How does one build an inexpensive array of handheld

Insight into Neutron Focusing: the Out-of-Focus Condition

October 1, 2013
Author(s)
Boualem Hammouda, David F. Mildner, A. Brulet, S. Desert
A three-pronged approach is used to investigate neutron focusing for small-angle neutron scattering instruments. The three methods are analytical calculations, resolution measurements, and computer simulations. A source aperture containing a single small

Greenhouse Gas Emissions and Dispersion #2. Comparison of FDS Predictions with Gas Velocity Measurements in the Exhaust Duct of a Stationary Source

April 25, 2013
Author(s)
Kuldeep R. Prasad, Kevin Li, Elizabeth F. Moore, Rodney A. Bryant, Aaron N. Johnson, James R. Whetstone
The burning of fossil fuels remains a major source of greenhouse gases responsible for global warming and climate change. In order to reduce greenhouse gas emissions, it is imperative to develop a capability to accurately measure these emissions from point

Practical Considerations for Implementing Homeland Security Models & Simulations

December 1, 2012
Author(s)
Charles W. Hutchings, Sanjay Jain, Yung-Tsun Lee, Charles McLean
Modeling and simulation (M&S) capabilities support reasoning in many domains and can provide powerful tools for homeland security analytical needs. For example, these capabilities are particularly valuable in exploring systems which are inaccessible for

Second Virial Coefficients of H2 and its Isotopologues from a Six-Dimensional Potential

October 17, 2012
Author(s)
Giovanni Garberoglio, Piotr Jankowski, Krzysztof Szalewicz, Allan H. Harvey
We employ path-integral Monte Carlo techniques to compute the second virial coefficient as a function of temperature for molecular hydrogen (H2), deuterium (D2), and tritium (T2), along with the mixed isotopologues HD, HT, and DT. The calculations utilize

An Analysis of Solver-Based Simulation Tools

March 7, 2012
Author(s)
Ion Matei, Conrad E. Bock
Computer-interpretable representations of systems’ structure and behavior are at the center of designing today’s complex systems. Engineers create and review such representations using (graphical) modeling languages that support specification, analysis

Graphene-metal interconnect: an atomistic simulation

August 11, 2011
Author(s)
Alexander Y. Smolyanitsky, Vinod K. Tewary
We develop a set of computationally efficient and accurate interatomic interactions for an atomistic simulation of the properties of graphene on nickel surface. The approach is based on the modified embedded atom method (MEAM) for the C-C and Ni-Ni

IEEE TC-10: Update 2011

July 1, 2011
Author(s)
Nicholas G. Paulter Jr., Thomas E. Linnenbrink, W. B. Boyer, S. J. Tilden, Travis Ellis
There is a world-wide need to standardize terms, test methods, and the computation of performance parameters for devices that generate, measure, and analyze waveforms. Users need to be able to unambiguously specify the device performance required for

Tumor Volume Measurement Errors of RECIST Studied With Ellipsoids

May 5, 2011
Author(s)
Zachary H. Levine, Benjamin R. Galloway, Adele P. Peskin, C. P. Heussel, Joseph J. Chen
RECIST (Response Evaluation Criteria in Solid Tumors) is a linear measure intended to predict tumor volume in medical computed tomography (CT). In this work, using purely geometrical considerations, we establish limits for how well RECIST can predict the

Who is Who? Biometrics provides answers for public and private sectors

February 10, 2011
Author(s)
Fernando L. Podio
One of the critical issues related to secured Information Technology (IT) systems and applications is the verification of the users identity. Biometrics provides for secure transactions, positive identification and augmentation to human judgment. For

Biological Cell Feature Identification by a Modified Watershed-Merging Algorithm

November 24, 2010
Author(s)
David E. Gilsinn, Kiran Bhadriraju, John T. Elliott
Biological cells are composed of many subsystems and organelles. The subsystem called the cytoskeleton is composed of long rod-shaped structures. They give the cell form and help attach the cell to the substrate and neighbors. One of the filaments is

AP210 Edition 2 Concept of Operations

March 26, 2010
Author(s)
Kevin G. Brady, Jamie Stori, Thomas Thurman
One of the most prevalent requirements of manufacturing industries today is the need to exchange and share product information within and between enterprises. This becomes almost impossible without a standardized, computer-interpretable method of

Quantitative Assessment of Robot-generated Maps

October 8, 2009
Author(s)
Christopher J. Scrapper Jr, Rajmohan Madhavan, Adam S. Jacoff, R Lakaemper, A Censi, Afzal A. Godil, Asim Wagan
Mobile robotic mapping is now considered to be a sufficiently mature field with demonstrated successes in various domains. While there has been much progress made in the development of computationally efficient and consistent mapping schemes, it is still

Ultra-cold mechanical resonators coupled to atoms in an optical lattice

September 17, 2009
Author(s)
Andrew Geraci, John E. Kitching
We propose an experiment utilizing an array of cooled micro-cantilevers coupled to a sample of ultra-cold atoms trapped near a micro-fabricated surface. The cantilevers allow individual lattice site addressing for atomic state control and readout, and

Extending the Mixture Fraction Concept to Address Under-Ventilated Fires

April 6, 2009
Author(s)
Kevin B. McGrattan, Jason E. Floyd
A common technique in computational fluid dynamics (CFD) modeling of fire is to assume single step, infinitely fast combustion, in which case the transport equations of all gas species can be combined into one for a single conserved scalar called the

Design and testing of a software feedback loop for RF power leveling

December 12, 2008
Author(s)
Xiaohai Cui, Thomas P. Crowley
We have developed a software feedback loop that stabilizes the RF power input in calorimetric measurements to better than 30 ppm. In this system, a bolometric sensor with a Type IV power meter is used to detect the power. Feedback is provided to the AM

Time and Frequency Transfer Activities at NIST

December 1, 2008
Author(s)
Victor S. Zhang, Michael A. Lombardi
The National Institute of Standards and Technology (NIST) maintains one of the world s most accurate and stable time scales, and also developed and maintains the primary frequency standard for the United States. Various techniques are used to compare the

Nature Materials News and Views on T. Haxhimali et al

October 16, 2008
Author(s)
James A. Warren
Simulations of dendritic solidification by T. Haxhimali et al. [1] for a pure material and comparisons with experiments in an A1Zn alloy system have shown that a standard theoretical rule of thumb for predicting solidification growth forms can dramatically

IEEE TC-10: Update 2008

September 22, 2008
Author(s)
Nicholas G. Paulter Jr., Thomas E. Linnenbrink, W. B. Boyer, Robert Graham, S. J. Tilden
There is a world-wide need to standardize terms, test methods, and the computation of performance parameters for devices that generate, measure, and analyze waveforms. Users need to be able to unambiguously specify the device performance required for
Displaying 5726 - 5750 of 7113
Was this page helpful?