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 30926 - 30950 of 73830

HIGH RESISTANCE SCALING FROM 10 k(OHM) AND QHR STANDARDS USING A CRYOGENIC CURRENT COMPARATOR

June 1, 2008
Author(s)
Randolph Elmquist, George R. Jones Jr., Brian J. Pritchard, Marcos E. Bierzychudek, Felipe L. Hernandez
We describe a cryogenic current comparator (CCC) bridge for resistance scaling that provides improved measurement uncertainty over a range of resistance values from 100 k(Ω) to 1 G(Ω). This CCC is designed for high resistance scaling based directly on a

Practical Combinatorial Testing: Beyond Pairwise

June 1, 2008
Author(s)
David R. Kuhn, Yu Lei, Raghu N. Kacker
With new algorithms and tools, developers can apply high-strength combinatorial testing to detect elusive failures that occur only when multiple components interact. In pairwise testing, all possible pairs of parameter values are covered by at least one

REACT: Reducing Early-Age Cracking Today

June 1, 2008
Author(s)
Dale P. Bentz, W Weiss
Concrete is generally viewed as a durable and long-lasting construction material. However, the long-term performance of a concrete structure can be greatly compromised by early-age cracking. One recent informal estimate from the industry places this as a

SIM COMPARISON OF DC RESISTANCE AT 1 Ohm, 1 MOhm, AND 1 GOhm

June 1, 2008
Author(s)
Dean G. Jarrett, Randolph Elmquist, Nien F. Zhang, Alejandra Tonina, Janice Fernandes, Daniel Izquierdo, Dave Inglis, Felipe Hernandez-Marquez
A regional comparison of DC resistance standards at the nominal values of 1 Ohm, 1 MOhm, and 1 GOhm has recently been completed in the System Interamericano de Metrogia (SIM) region. The motivation, design, standards, and results of this regional

Transformer-Like Devices for High-Accuracy Current Measurements.

June 1, 2008
Author(s)
T. M. Souders
A theoretical and practical framework is presented to aid in the design, fabrication and testing of transformer-like devices for use in high-accuracy ac current metering applications. Current transformers, two-stage current transformers, and current

UNCERTAINTY EVALUATION IN A TWO-TERMINAL CRYOGENIC CURRENT COMPARATOR

June 1, 2008
Author(s)
Marcos E. Bierzychudek, Randolph Elmquist
In this paper we present the uncertainty evaluation of a new cryogenic current comparator (CCC) bridge designed to compare two-terminal 1M Ω} and 10M Ω} standard resistors with the quantized Hall resistance (QHR) and then scale from these values to other

Low Signal-to-noise Ratio Underwater Acoustic Communications

May 31, 2008
Author(s)
Wen-Bin Yang, T.C. Yang
Communications with low input signal-to-noise ratio (SNR) is often called covert communications as the probability of detection and interception decreases with decreasing SNR . Direct-sequence spread-spectrum signaling works at low SNR because of the

Interfacial Characterization of Multiple Layer Coatings on Thermoplastic Olefins (TPO)

May 30, 2008
Author(s)
Aaron M. Forster, Chris A. Michaels, Justin Lucas, Li Piin Sung
Thermoplastic olefins (TPO) have made significant inroads as polymeric materials for interior and exterior automotive parts. Spray applied chlorinated polyolefins (CPO) are often used to improve paint adhesion to the low surface energy TPO substrates. The

Internet Protocol Version 6 (IPv6)

May 30, 2008
Author(s)
Sheila E. Frankel, David Green
Recognizing that the 32-bit addresses used by the current version of the Internet Protocol (IPv4) would soon be depleted, the Internet Engineering Task Force (IETF) has been developing its successor, Internet Protocol version 6 (IPv6). This has been a more

Trophic Transfer of Nanoparticles in a Simplified Food Web

May 30, 2008
Author(s)
Richard D. Holbrook, Karen E. Murphy, Jayne B. Morrow, Kenneth D. Cole
Nanotechnological innovations depend largely on the unique chemical and physical properties of engineered nanomaterials. However, the same properties that make engineered nanomaterials attractive for numerous applications also contribute to their

Astronomical spectrograph calibration with broad-spectrum frequency combs

May 29, 2008
Author(s)
Danielle Braje, Matthew S. Kirchner, Tara M. Fortier, Scott A. Diddams, Leo W. Hollberg, Steve Osterman
Broad-band frequency combs are filtered to spectrographically resolvable frequency-mode spacing, and the limitations of using cavities for spectral filtering are considered. Data and theory are used to show implications to spectrographic calibration of
Displaying 30926 - 30950 of 73830
Was this page helpful?