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NIST Authors in Bold

Displaying 5651 - 5675 of 74115

Expanding NIST’s Calibration of Fluorescent Microspheres for Flow Cytometry to More Fluorescence Channels and Smaller Particles

September 16, 2020
Author(s)
Paul C. DeRose, Linhua Tian, Elzafir B. Elsheikh, Aaron A. Urbas, Yu-Zhong Zhang, Lili Wang
NIST, NIH and other industry stakeholders have been working together to enable fluorescence intensities of flow cytometer calibration beads to be assigned quantitative “ERF” values with high accuracy and precision. The ultimate goal of this effort is to

Microwaves and Microscopy (Guest Editorial)

September 16, 2020
Author(s)
Thomas M. Wallis, Marco Farina
Welcome to this special issue of IEEE Microwave Magazine, which is focused on the topic of “Microwaves and Microscopy.” As that title implies, this topic lies at the intersection of two technical disciplines, namely microwave engineering and measurements

NIST Interactions: Fiscal Year 2015 through Fiscal Year 2018

September 16, 2020
Author(s)
Nicole K. Gingrich, Isaac Patterson, Jimmy Nazario-Negron, Michael J. Hall
This study analyzes data from fiscal years 2015 through 2018 of eighteen interaction types in which NIST participates annually. To describe the volume of direct relationships NIST has with the U.S. economy, it calculates the average number of interactions

NIST/NIH Vitamin D Metabolites Quality Assurance Program (VitDQAP): Final Report

September 16, 2020
Author(s)
Katrice A. Lippa, Mary Bedner, Susan Tai, Carolyn Q. Burdette
The National Institute of Standards and Technology (NIST) established a Vitamin D Metabolites Quality Assurance Program (VitDQAP) in collaboration with the National Institutes of Health Office of Dietary Supplements (NIH-ODS) in 2009. The VitDQAP at NIST

Characterization of 3-Dimensional Printing and Casting Materials for use in Computed Tomography and X-ray Imaging Phantoms

September 15, 2020
Author(s)
Bryan E. Yunker, Andrew Holmgren, Karl Stupic, J. L. Wagner, S Huddle, R Shandas, R. F. Weir, Katy Keenan, Edward Garboczi, Stephen E. Russek
Imaging phantoms are used to calibrate and validate the performance of medical computed tomography (CT) systems. Many new materials developed for three-dimensional (3D) printing processes may be useful in the direct printing or casting of biomimetic and

Characterization of 3-Dimensional Printing and Casting Materials for use in Magnetic Resonance Imaging Phantoms at 3 T

September 15, 2020
Author(s)
Bryan E. Yunker, Karl Stupic, J. L. Wagner, S Huddle, R Shandas, R. F. Weir, Stephen E. Russek, Katy Keenan
Imaging phantoms are used to calibrate and validate the performance of magnetic resonance imaging (MRI) systems. Many new materials have been developed for additive manufacturing (three-dimensional [3D] printing) processes that may be useful in the direct

Correlating Inter-Particle Forces and Particle Shape to Shear-Induced Aggregation/Fragmentation and Rheology for Dilute Anisotropic Particle Suspensions: A Complementary Study via Capillary Rheometry and in situ small and Ultra-Small Angle X-ray Scatterin

September 15, 2020
Author(s)
Anthony J. Krzysko, Elias Nakouzi, Xin Zhang, Trent R. Graham, Kevin M. Rosso, Gregory K. Schenter, Jan Ilavsky, Ivan Kuzmenko, Matthew G. Frith, Cornelius F. Ivory, Sue B. Clark, Javen S. Weston, Kathleen Weigandt, James J. De Yoreo, Jaehun Chun, Lawrence M. Anovitz
Predicting the stability of suspensions composed of anisotropic particles is difficult due to the complexity and interplay of hydrodynamic and colloidal forces. For example, it is not well understood how non-spherical particle shapes affect suspension

Electron and x-ray focused beam-induced cross-linking in liquids: Toward rapid continuous 3D nanoprinting and interfacing using soft materials

September 15, 2020
Author(s)
Tanya Gupta, Evgheni Strelcov, Glenn Holland, Joshua D. Schumacher, Yang Yang, Mandy Esch, Vladimir Aksyuk, Patrick Zeller, Matteo Amati, Luca Gregoratti, Andrei Kolmakov
Additive fabrication of biocompatible 3D structures out of liquid hydrogel solutions has become pivotal technology for tissue engineering, soft robotics, biosensing, drug delivery etc. Electron and X-ray lithography are well suited to pattern nanoscopic

Evaluating the Operational Impact of Contactless Fingerprint Imagery on Matcher Performance

September 15, 2020
Author(s)
Shahram Orandi, John M. Libert, Bruce Bandini, Kenneth Ko, John D. Grantham, Craig I. Watson
This study set out to examine the operational impact of introducing contactless fingerprint imagery to a modern fingerprint matching system that was designed for touch-collected images in either a standard Ten-Print operational matching pathway or a Mobile

Mobile Device Security: Corporate-Owned Personally-Enabled (COPE)

September 15, 2020
Author(s)
Gema E. Howell, Kaitlin R. Boeckl, Naomi B. Lefkovitz, Ellen M. Nadeau, Joshua M. Franklin, Behnam Shariati, Jason Ajmo, Christopher J. Brown, Spike E. Dog, Frank Javar, Michael Peck, Kenneth F. Sandlin
Mobile devices provide access to vital workplace resources while giving employees the flexibility to perform their daily activities. Securing these devices is essential to the continuity of business operations. While mobile devices can increase efficiency

On the Use of Machine Learning Models to Forecast Flashover Occurrence in a Compartment

September 15, 2020
Author(s)
Jun Wang, Andy Tam, Paul A. Reneke, Richard Peacock, Thomas Cleary, Eugene Yujun Fu, Grace Ngai, Hong Va Leong
This paper presents a study to examine the potential use of machine learning algorithms to build a model to forecast the likelihood of flashover occurrence for a single-floor multi-room compartment. Synthetic temperature data for heat detectors from

Time Series Feature Extraction and Selection Tool for Fire Data

September 15, 2020
Author(s)
Jun Wang, Youwei Jia, Eugene Yujun Fu, Jiajia Li, Andy Tam
This paper aims to facilitate the use of machine learning to carry out supervised classification/regression tasks for time series data in fire research. Specifically, a feature engineering tool, FAST (Feature extrAction and Selection for Time-series), is

Transport dynamics in a high-brightness magneto-optical-trap Li ion source

September 15, 2020
Author(s)
Jamie Gardner, William R. McGehee, Mark D. Stiles, Jabez J. McClelland
Laser-cooled gases offer an alternative to tip-based methods for generating high brightness ions for focused ion beam applications. These sources produce ions by photoionization of ultracold neutral atoms, where the narrow velocity distribution associated

Ultraprecise optical-frequency stabilization with heterogeneous III-V/Si lasers

September 15, 2020
Author(s)
Liron Stern, Wei Zhang, Lin Chang, Joel Guo, Chao Xiang, Minh A. Tran, Duanni Huang, Jon Peters, David Kinghorn, John E. Bowers, Scott Papp
Demand for low-noise, continuous-wave, frequency-tunable lasers based on semiconductor integrated photonics has been advancing in support of numerous applications. In particular, an important goal is to achieve narrow spectral linewidth, commensurate with

Calibration of free-space and fiber-coupled single-photon detectors

September 14, 2020
Author(s)
Thomas Gerrits, Alan L. Migdall, Joshua C. Bienfang, John H. Lehman, Sae Woo Nam, Oliver T. Slattery, Jolene D. Splett, Igor Vayshenker, Chih-Ming Wang
We present our measurements of the detection efficiency of free-space and fiber-coupled single- photon detectors at wavelengths near 851 nm and 1533.6 nm. We investigate the spatial uniformity of one free-space-coupled silicon single-photon avalanche diode

Comparison of theoretical and experimental failure distributions for twisted yarns

September 14, 2020
Author(s)
Amy E. Engelbrecht-Wiggans, Amanda L. Forster
Both untwisted and twisted bundles of fibers and wires can be found in a myriad of applications, from ballistic body armor to suspension bridge cables. Predicting the bulk bundle failure distribution based on single fiber or wire tests is of interest as

Digital Radiometer for Traceable Spectrum Sensing

September 14, 2020
Author(s)
Xifeng Lu, Dazhen Gu, Daniel G. Kuester
This paper describes a metrology instrument designed for detecting noise and interference in digital communications. A quadrature detector downconverts in-phase (I) and quadrature (Q) channels, which are each digitized at high speed. This architecture

NIST NeXT: a system for truly simultaneous neutron and X-ray tomography

September 14, 2020
Author(s)
Jacob LaManna, Daniel S. Hussey, Victoria H. DiStefano, Eli Baltic, David L. Jacobson
Neutrons and X-rays provide excellent complementary, nondestructive probes to understand internal structure of systems across engineering and material science. With its sensitivity to hydrogen, neutrons excel at separating fluids, such as water or oil
Displaying 5651 - 5675 of 74115