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John H. Lehman, C J. Chunnilall, Evangelos Theocharous, Aric W. Sanders
We present the absolute infrared (5 μm to 50 μm) reflectance of films produced from commercially available carbon nanotubes. Data were obtained using the upgraded NPL directional- hemispherical reflectance measurement facility. A brief description of this
Jin Chu Wu, Alvin F. Martin, Craig S. Greenberg, Raghu N. Kacker
The National Institute of Standards and Technology conducts an ongoing series of Speaker Recognition Evaluations (SRE). Speaker detection performance is measured using a detection cost function defined as a weighted sum of the probabilities of type I and
This article provides background information on the development of the International vocabulary of basic and general terms in metrology (VIM) documents over the past several years, and to provide some explanation and elaboration on several of the
Dean C. Ripple, William E. Murdock, Gregory F. Strouse, Keith A. Gillis, Michael R. Moldover
We have successfully conducted highly-accurate, primary acoustic thermometry at 600 K using a sound source and a sound detector at room temperature. We describe the source, the detector, and the ducts that connected them to our cavity resonator. This
Svetlana Avramov-Zamurovic1, Jae M. Yoo, Nicholas Dagalakis, Rae Duk Lee
This paper describes the design of a nano displacement sensor that detects the presence of a moving platform by using fringing electric field. Its electrodes are commercially prefabricated Teflon insulated wires. This solution provides for excellent
Paul D. Hale, Dylan F. Williams, Andrew M. Dienstfrey, Chih-Ming Wang, Jeffrey A. Jargon, David Humphreys, Matthew Harper, Heiko Fuser, Mark Bieler
Instruments for measuring high-speed waveforms typically require calibration to obtain accurate results. The national metrology institutes of the United States of America, the United Kingdom, and Germany offer measurement services based on electro-optic
At the National Institute of Standards and Technology a new watt balance, NIST-4, is currently being designed. This apparatus will be used to realize the base unit of mass after the redefinition of the SI has taken effect. As a realization device, NIST-4
Alain Rufenacht, Charles J. Burroughs, Samuel Benz, Paul Dresselhaus
Commercially available 20-bit digital to analog converters (DACs) have the potential to impact the field of low frequency voltage metrology. We measured a linearity of ±6 µV (±0.6 µV/V full scale) over the 10 V range for such a DAC with a Zener voltage
Thomas M. Wallis, Thomas P. Crowley, Denis X. LeGolvan, Ronald A. Ginley
A direct comparison system for calibration of power sensors with 1.85 mm precision coaxial connectors up to 67 GHz has been developed. The comparison is implemented in two frequency bands. Between 10 MHz and 50 GHz, power sensors with 2.4 mm coaxial
Dazhen Gu, James P. Randa, Robert L. Billinger, Dave K. Walker
We report a verification method for noise-temperature(NT) measurements on cryogenic low-noise amplifiers (LNAs) at liquid helium temperature. The method uses a comparison between the individual measurements of the LNA and an attenuator and the joint
Dazhen Gu, Derek A. Houtz, James P. Randa, Dave K. Walker
We report a verification method for noise-temperature (NT) measurements on cryogenic low noise amplifiers (LNAs) at liquid helium temperature. The method uses the comparison between the individual measurements of the LNA and an attenuator and the joint
Thomas M. Wallis, Atif A. Imtiaz, Alexandra Curtin, Pavel Kabos, H. P. Huber, Joseph J. Kopanski, F. Kienberger
Two techniques are described for calibrating a scanning microwave microscope (SMM). The first technique enables spatially-resolved absolute capacitance measurements on the attofarad-to-femtofarad scale. The second technique enables profiling or dopant
Xiaoyu Alan Zheng, Robert M. Thompson, Todd Weller
Ten (10) pistol slides with consecutively manufactured breech faces, were obtained from Sturm, Ruger Co, Inc. A total of nine (9) test fires from each pistol, for a total of ninety (90) test fired cartridge cases, were compared using comparison microscopy
Alain Rufenacht, Charles J. Burroughs, Samuel Benz, Paul Dresselhaus
A 10 V programmable Josephson voltage standard has enabled sine waves with rms voltages up to 7 V to be accurately measured with differential sampling methods. This paper reviews the challenges and limitations of differential sampling that arise when rms
Jifeng Qu, Samuel Benz, Yang Fu, Jianqiang Zhang, Horst Rogalla, Alessio Pollarolo
A new quantum voltage calibrated Johnson noise thermometer (JNT) was developed at NIM to demonstrate the electrical approach that determines the Boltzmann constant k by comparing electrical and thermal noise power. A measurement with integration period of
Alessio Pollarolo, Tae H. Jeong, Samuel Benz, Horst Rogalla
In 2010 NIST measured the Boltzmann constant k by use of an electronic technique that measured the Johnson noise of a 100 Ohm resistor at the triple point of water (TPW). The NIST Johnson noise thermometry (JNT) system used as a reference a voltage
Charles J. Burroughs, Alain Rufenacht, Samuel P. Benz, Paul D. Dresselhaus
The amplitudes of stepwise-approximated sine waves produced by programmable Josephson voltage standards (PJVSs) are not intrinsically accurate because the transitions between the quantized voltages depend on numerous conditions. We have developed a method
Thomas Hagen, Ilya F. Budovsky, Samuel Benz, Charles J. Burroughs
A pulse driven ac Josephson voltage standard (ACJVS) has been set up at the National Measurement Institute, Australia (NMIA) with the help of the National Institute of Standards and Technology (NIST). The ACJVS forms the basis of a high precision
This paper describes an on-going activity to develop an international document standard for defining rectangular metallic waveguides for use in the submillimeter-wave/terahertz frequency range. The IEEE's Microwave Theory & Techniques Society (MTT-S) is
As the electric power grid is changing to a smarter more dynamically controlled system, there is increasing need for measurements that show the global status of the system for wide-area monitoring and control. These measurements require time
Darine El Haddad, Stephan Schlamminger, David B. Newell, Ruimin Liu, Edwin R. Williams, Jon R. Pratt
The scientific community is presently engaged in a historic attempt to fix the value of the Planck constant h so that it might ultimately serve as a base constant in a revised system of units. To assist this effort, NIST is examining its existing watt
Behrang H. Hamadani, John F. Roller, Brian P. Dougherty, Howard W. Yoon
An absolute differential spectral response measurement system for solar cells is presented. The system couples an array of light emitting diodes (LEDs) with an optical waveguide to provide large area illumination. Two unique yet complementary measurement
Rajmohan (. Madhavan, Stephen B. Balakirsky, Craig I. Schlenoff
A seminar titled "Next Generation Packaging, Kitting, and Palletizing: Can one robot do it all?" was held on February 9th 2012 at the Material Handling Industry of America (MHIA) MODEX show in Atlanta, GA. The seminar primarily focused on whether systems
Roger V. Bostelman, William P. Shackleford, Geraldine S. Cheok, Kamel S. Saidi
The National Institute of Standards and Technology's Intelligent Systems Division has been researching several areas leading to safe control of manufacturing vehicles to improve AGV safety standards. The research areas include: - Automated guided vehicle
The binary systems ethanol + 2,2,4-trimethylpentane and 2-butanol + 2,2,4-trimethylpentane were studied as models for blends of gasoline with biofuels. Their densities were measured with a vibrating-tube densimeter at compressed-liquid states of three