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The National Institute of Standards and Technology (NIST) uses a laser Doppler anemometer (LDA) as a working standard for airspeed calibrations in the range 0.15 m/s to 75 m/s (0.34 to 168 miles/hour). We report improved procedures for calibrating the LDA
Jessica M. Torres, Christopher Stafford, Bryan D. Vogt
In this work, we examine the influence of relative molecular mass (Mn, or the number average molecular mass) of PS on the thickness-dependent moduli using a wrinkling based instability of a stiff film on an elastic substrate. This wrinkling based metrology
We demonstrate that thermal wrinkling can be utilized to measure the rubbery modulus and shear viscosity of polystyrene (PS) thin films as a function of temperature. Specifically, we use surface laser-light scattering (SLS) to characterize the wrinkled
Joan Pellegrino, Arthur H. Fanney, Andrew K. Persily, Piotr A. Domanski, William M. Healy, Steven T. Bushby
Buildings account for nearly a third of the world s energy use today, and this share is expected to rise along with population growth and levels of prosperity. In the United States, residential and commercial buildings consume about 40% of primary energy
Neutron imaging has been a unique, precise, measurement tool for water transport in proton exchange membrane fuel cells (PEMFCs), enabling the direct measurement of the water distribution in standard, commercially viable fuel cell hardware. Thus, in the
We propose a method of determining the radial clearance between the piston and cylinder of a gas piston gauge using a capacitive technique. This method allows a determination of the effective area of a piston gauge pressure standard, independent of
Mark A. Przybocki, Kay Peterson, P. S. Bronsart, Gregory A. Sanders
This paper discusses the evaluation of automated metrics developed for the purpose of evaluating machine translation (MT) technology. A general discussion of the usefulness of automated metrics is offered. The NIST MetricsMATR evaluation of MT metrology is
Effects of sample surface free energy (s) and relative humidity (RH) of the tip-sample environment on image contrast and friction characteristics measured with lateral force microscopy (LFM) have been investigated. Samples having a wide range of surface
Coralie Bernard, Tinh Nguyen, Bastien T. Pellegrin, Mat Celina, Alexander J. Shapiro, Deborah Jacobs, Kar T. Tan, Sungjin Park, R. S. Ruoff, Joannie W. Chin
Graphene oxides are potentially a new class of nanomaterial to enhance multifunctional properties of polymers because of their remarkable thermal conductivity, mechanical strength, and more importantly, low cost. The graphene oxides, produced by
Arvind K. Balijepalli, Thomas W. LeBrun, Satyandra K. Gupta
Significant speedup is possible when using the Graphics Processing Unit (GPU) for stochastic particle simulations. A simulation of freely diffusing spherical particles using Langevin's equation has been developed and the results from the CPU and GPU
This report summarizes results from the first year of a 2-year project to develop a simulator for electron beam (e-beam) inspection and critical dimension-scanning electron microscope (CD-SEM) inline metrology tools. The goal is to improve on previous
Wei Chu, Jun-Feng Song, Theodore V. Vorburger, James H. Yen, Susan M. Ballou, Benjamin Bachrach
A procedure for automated bullet signature identification is described based on topography measurements using confocal microscope and correlations calculation. Automated search and retrieval systems are widely used for comparison of firearms evidence. In
Aimed at improving quality assurance and quantitation for modern fluorescence techniques, ASTM is about to release a Standard Guide for Fluorescence, reviewed here. The guide s main focus is on steady state fluorometry, for which available standards and
The relationship between AFM probe-sample adhesion force and relative humidity (RH) at five different levels of surface free energy (γs) of an organic self-assembled monolayer (SAM) has been investigated. Different γs levels were achieved by exposing a
The magnetic vortex structure is an equilibrium configuration frequently found in patterned magnetic nanostructures. It is characterized by an in-plane curling of the magnetization with clockwise or anticlockwise chirality and by an out of plane vortex
A local excitation of ferromagnetic resonance (FMR) and its detection were performed by using an open-ended radio frequency (RF) probe. THe RF probe is composed of a coaxial cable transmitting broadband RF waves over 10 GHz and a sharp tip attached to its
This paper describes the methods used during formative utility assessments for speech-to-speech, real-time translation systems intended for tactical use. The systems, while still prototypical, had hardware platforms that could be exercised indoors or
Dylan F. Williams, Catherine A. Remley, Joe Gering, Grand Aivazian
We develop a procedure and metrics for comparing large-signal-network-analyzer calibrations. The metrics we develop provide a bound on differences between measurements obtained from large-signal-network-analyzer calibrations, as well as more specific
Ryna B. Marinenko, Shirley Turner, David S. Simons, Savelas A. Rabb, Rolf L. Zeisler, Lee L. Yu, Dale E. Newbury, Rick L. Paul, Nicholas W. Ritchie, Stefan D. Leigh, Michael R. Winchester, Lee J. Richter, Douglas C. Meier, Keana C. Scott, D Klinedinst, John A. Small
Bulk SiGe wafers cut from single-crystal boules and two SiGe thick films (4 m and 5 m thick) on Si wafers were evaluated with the electron probe microanalyzer for the extent of heterogeneity and composition for use as reference materials needed by the
These specifications and tolerances are recommended as minimum requirements for standards used by state and local weights and measures officials and others in the regulatory verification of meters used in quantity determination of pressurized liquid
Jun-Feng Song, Theodore V. Vorburger, Robert M. Thompson, Thomas Brian Renegar, Xiaoyu Alan Zheng, Li Ma, James H. Yen, Martin Ols
The National Institute of Standards and Technology (NIST) in collaboration with the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) has developed the Standard Reference Material (SRM) 2460 bullets and 2461 casings. NIST and ATF are proposing to
These specifications and tolerances are recommended as minimum requirements for standards used by state and local weights and measures officials and others in the regulatory verification of meters used in quantity determination of liquid commodities. Other
Tsai Hong Hong, Elena R. Messina, Hui-Min Huang, Michael O. Shneier, Roger D. Eastman, Jane Shi, James Wells
The Dynamic Perception workshop was intended to further the development of standardized, reproducible, and portable test methods that can advance the technology of sensors and perception systems for new, flexible robotic and automation applications in
The vibrations of the cold finger of a low-vibration helium pulse-tube cryostat are measured from 1 Hz to 20 kHz using an optical interferometer specially designed to measure small vibrations at high frequencies in the presence of large vibrations at lower