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Search Publications

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Displaying 2601 - 2625 of 74629

Gauging the difficulty of image segmentation

May 19, 2022
Author(s)
Marek Franaszek
Image segmentation is the first step in a complex process of object recognition. This report presents a method to gauge the difficulty of segmentation by calculating a scalar parameter Q for an image. This parameter depends on a distribution of the

Advances in the \sc ocean}-3 spectroscopy package

May 18, 2022
Author(s)
John Vinson
The \sc ocean} code for calculating near-edge x-ray spectra using the Bethe-Salpeter equation is briefly reviewed. The code is capable of calculating UV/Vis, near-edge x-ray absorption or non-resonant scattering, and resonant inelastic x-ray scattering

Intrinsically accurate sensing with an optomechanical accelerometer

May 18, 2022
Author(s)
Benjamin Reschovsky, David Long, Feng Zhou, Yiliang Bao, Richard A. Allen, Jason J. Gorman, Thomas W. LeBrun
We demonstrate a microfabricated optomechanical accelerometer that is capable of percent-level accuracy without external calibration. To achieve this capability, we use a mechanical model of the device behavior that can be characterized by the thermal

Machine learning enabling high-throughput and remote operations at large-scale user facilities

May 18, 2022
Author(s)
Bruce D. Ravel, Tatiana Konstantinova, Phillip Michael Maffettone, Stuart Campbell, Andi Barbour, Daniel Olds
Imaging, scattering, and spectroscopy are fundamental in understanding and discovering new functional materials. Contemporary innovations in automation and experimental techniques have led to these measurements being performed much faster and with higher

Development and Analysis of a Database of Tornado Impacts on U.S. Critical Facilities

May 17, 2022
Author(s)
Nicholas de Toledo, Marc Levitan, Jamil Malik, Warren Stewart, Katherine Johnson, Patrick Crawford
Despite the significant hazard that tornadoes pose, much remains to be learned about the impacts of tornadoes on critical facilities in the United States. While a number of post-storm reports have documented the damage from individual tornadoes or tornado

High throughput nanoimaging of thermal conductivity and interfacial thermal conductance

May 17, 2022
Author(s)
Mingkang Wang, Georg Ramer, Diego Perez, Georges Pavlidis, Jeffrey Schwartz, Liya Yu, Robert Ilic, Vladimir Aksyuk, Andrea Centrone
Thermal properties of materials are often determined by measuring thermalization processes. Measuring such properties at the nanoscale, however, requires high sensitivity, high temporal, and high spatial resolutions concurrently, which is beyond the

Speed of Sound Measurements of Binary Mixtures of 1,1,1,2-Tetrafluoroethane (R-134a), 2,3,3,3-Tetrafluoropropene (R-1234yf), and trans-1,3,3,3-Tetrafluoropropene (R-1234ze(E)) Refrigerants

May 17, 2022
Author(s)
Aaron Rowane, Richard A. Perkins
Speed of sound data measured using a dual-path pulse-echo instrument are reported for binary mixtures of 1,1,1,2-tetrafluoroethane (R-134a), 2,3,3,3-tetrafluoropropene (R-1234yf), and trans-1,3,3,3-tetrafluoropropene (R-1234ze(E)). For each binary mixture

Multi-User MIMO Enabled Virtual Reality in IEEE 802.11ay WLAN

May 16, 2022
Author(s)
Jiayi Zhang, Steve Blandino, Neeraj Varshney, Jian Wang, Camillo Gentile, Nada T. Golmie
Virtual reality (VR) coupled with 360° video has been used in a variety of areas, including gaming, remote learning, and healthcare, among others. The 360° video on which VR applications are based today is mostly low resolution and, in order to improve the

SCAP Composer User Guide

May 16, 2022
Author(s)
Joshua Lubell
SCAP Composer is a software application from the National Institute of Standards and Technology (NIST) for creating Security Content Automation Protocol (SCAP – pronounced "ess-cap") source data stream collections. A source data stream collection is a

Absorption-Based Ranging from Ambient Thermal Radiation without Known Emissivities

May 15, 2022
Author(s)
Unay Dorken Gallastegi, Hoover Rueda-Chacon, Marty Stevens, Vivek Goyal
We present passive absorption-based ranging using long-wave infrared hyperspectral measurements of an outdoor scene. Regularization and parametric modeling of transmittance enable good accuracy without knowing temperatures or emissivities of scene objects

Time Programmable Frequency Comb

May 15, 2022
Author(s)
Emily Caldwell, Laura Sinclair, Nathan R. Newbury, Jean-Daniel Deschenes
We demonstrate a programmable optical frequency comb that emits coherent pulses with user-specified time and phase at sub-10 attosecond accuracy while maintaining the underlying referenced stability characteristic of combs.
Displaying 2601 - 2625 of 74629