An official website of the United States government
Here’s how you know
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.
Geraldine S. Cheok, Marek Franaszek, Karl Van Wyk, Jeremy A. Marvel
Accurate knowledge of an object's location is essential in automated robotic applications such as machine tending, pick-and-place operations, and part assembly. Perception systems are used to acquire the object's location, and this information is then
There has been an increasing push to derive quantitative measurements using optical microscopes. While several aspects of microscopy have been identified to enhance quantitative imaging, non- uniform angular illumination asymmetry (ANILAS) across the field
Alain Rufenacht, Stephane Solve, M Maruyama, Chiharu Urano, Nobu Kaneko
For the first time, the BIPMs new transportable programmable Josephson voltage standard (PJVS) has been used for an on-site comparison at the National Metrology Institute of Japan (NMIJ), the National Institute of Advanced Industrial Science and
Douglas A. Olson, Haijun Liu, Zeeshan Ahmed, Kevin O. Douglass
Here we detail our progress in developing the infrastructure for traceable transient measurements of pressure and temperature. Towards that end, we have built and characterized a dual diaphragm shock tube that allows us to achieve shock amplitude
George C. Rhoderick, Michael E. Kelley, Walter R. Miller Jr., James E. Norris, Jennifer Carney, Lyn Gameson, Christina Cecelski, Cassie Goodman, Abneesh Srivastava, Joseph Hodges
There are many gas species present in the atmosphere that are associated with the earths climate. These compounds absorb and emit radiation, a process which is the fundamental cause of the greenhouse effect. The major greenhouse gases in the earths
Exoskeletons are devices that can assist the human wearer's limbs to provide functional, normal or amplified human capabilities. Recent research on exoskeletons has dramatically increased. However, measurements of these devices have yet to show long-term
Fabry-Perot interferometer sensors have been widely used in Micro-Electro-Mechanical-Systems (MEMS) due to high displacement accuracy and immunity to electromagnetic noises, but they are still limited by micro scale measurement range. In this paper, a
Christopher L. Soles, Richard A. Vaia, Ronald Pindak
The round-table participants concluded that facilities at NSLS-II provide immediate opportunities to address some of the critical processing and measurement challenges that are blocking the path towards a sustainable US-centric Flexible Hybrid Electronic
Ross N. Andrews, Suresh Narayanan, Fan Zhang, Ivan Kuzmenko, Jan Ilavsky
X-ray photon correlation spectroscopy (XPCS) and dynamic light scattering (DLS) reveal dynamics by interference of coherent scattering, but X-rays permit interrogation of dynamics in a much more diverse array of materials. Heterogeneous dynamics occur in
Joseph A. Hagmann, Xiqiao Wang, Pradeep N. Namboodiri, Jonathan E. Wyrick, Roy E. Murray, Michael D. Stewart, Richard M. Silver
The key building blocks for devices based on the deterministic placement of dopants in silicon are the formation of phosphorus dopant monolayers and the overgrowth of high quality crystalline Si. Lithographically defined dopant delta-layers can be formed
Steven Lund, Sanem Hosbas Coskun, Monique Johnson, Christopher Sims, Elijah Petersen, John T. Elliott, Bryant C. Nelson, Leona D. Scanlan, Shannon K. Hanna, Karina Brignoni, Patricia Lapasett
The nematode Caenorhabditis elegans is used extensively in molecular, toxicological and genetics research. However, standardized methods for counting nematodes in liquid culture do not exist despite the wide use of nematodes and need for accurate
Roy E. Murray, Justin K. Perron, Michael D. Stewart, Neil M. Zimmerman
Pumping single electrons at a set rate is being widely pursued as an electrical current standard. Much work has been done on pumping using a single AC signal, but using multiple coordinated AC signals may help lower error rates. Whether pumping with one or
Jay H. Hendricks, Patrick F. Egan, Jacob E. Ricker, Jack A. Stone Jr., Kevin O. Douglass, Gregory F. Strouse
A team of NIST scientists is working to fundamentally change the way that the unit of pressure is realized and disseminated, an effort that will lead to the elimination of mercury barometer pressure standards.
It is generally acknowledged that few security metrics have the level of predictive validity that their uses require, but neither the nature of the problem nor the steps needed to avoid it have been fully characterized. This article examines both questions
We investigate the performance of pose measuring systems which determine an object's pose from measurement of a few fiducial markers attached to the object. Such systems use point-based, rigid body registration to get the orientation matrix. Uncertainty in
Samples of Gorilla® glass (Corning®) from several touchscreen mobile phones were prepared and analyzed using phototransferred thermoluminescence (PTTL) in an attempt to retrospectively assess radiation doses absorbed by the glass for potential applications
Stephan Schlamminger, Harald Bosse, Horst Kunzmann, Jon R. Pratt, Ian Robinson, Michael de Podesta, Paul Shore, Paul Morantz
All measurements performed in science and industry are based on the International System of Units, the SI. It has been proposed to revise the SI following an approach which had already been implemented for the redefinition of the unit of length, the metre
Traceability of a measurement requires two parts. An unbroken chain of measurements and uncertainties for each link of the chain. The NIST Microwave Uncertainty Framework (MUF) can provide both the required parts for a single link in the chain or for
Three grid-connected monocrystalline silicon arrays on the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland have been instrumented and monitored for one year, with minimal gaps in the data sets. These arrays range from 73 kW
Prem K. Rachakonda, Balasubramanian Muralikrishnan, Daniel S. Sawyer, Ling Wang
Terrestrial laser scanners (TLSs) are instruments that can measure 3D coordinates of objects at high speed resulting in high density 3D point cloud data without the necessity of a cooperative target. Contrast targets, also known as checkerboard targets