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With the gaining popularity of performance-based engineering, it is essential to have reliable estimates of component (e.g., steel beam or column) performance...
Mobile edge computing (MEC) is an emerging paradigm that integrates computing resources in wireless access networks to process computational tasks in close...
For accurate realization of the ac volt, the Josephson Arbitrary Waveform Synthesizer (JAWS) must not be overly loaded by the electrical network in which it is...
Alexandra Artusio-Glimpse, Ivan Ryger, Natalia A. Azarova, Paul A. Williams, John Lehman
Demonstration and validation of a linear radiation pressure-based high-power laser power meter is presented. To date, this device is the most promising real...
We investigate laser spot welding of 200 µm thick Cu and Al foils using laser-induced fluorescence (LIF). The key to strong Cu/Al welds is limited intermetallic...
Justus A. Brevik, Alirio De Jesus Soares Boaventura, Manuel C. Castellanos Beltran, Christine A. Donnelly, Nathan E. Flowers-Jacobs, Anna E. Fox, Peter F. Hopkins, Paul D. Dresselhaus, Dylan Williams, Samuel P. Benz
We performed a preliminary calibrated measurement of the output power of a Josephson arbitrary waveform synthesizer up to 1 GHz. We present the results and...
Brian Simonds, Jack R. Tanner, Alexandra B. Artusio-Glimpse, Paul A. Williams, Niranjan Parab, Cang Zhao, Tao Sun
During high-power laser metal processing, the absorbed light is intimately related to the molten metal cavity shape. For the first time, we directly and...
S. Yang, Stefan Cular, Alain Rufenacht, Charles J. Burroughs, Paul Dresselhaus, Samuel Benz, M. N. Ng
Standards and Calibration Laboratory (SCL) setup in 2018 a liquid helium based programmable Josephson voltage standard (PJVS) developed by the National...
The use of laser-induced fluorescence for detecting Cu in the vapor plume under laser welding conditions is investigated. It is found that LIF is sensitive...
This study investigates the thermal conductivity of 17-4PH stainless steel powder that was encapsulated into hollow specimens with different internal geometries...
Chunmei Liu, Chen Shen, Jack Chuang, Richard A. Rouil, Hyeong-Ah Choi
Public safety incidents typically involve a significant amount of group traffic and have a stringent requirement of connection reliability. Hence multicast...
One of the most prevalent additive manufacturing processes, the powder bed fusion process, is driven by a moving heat source that melts metals to build a part...
The issue of Additive Manufacturing (AM) energy consumption attracts attention in both industry and academia, as the increasing trend of AM technologies being...
Nenad Ivezic, Elena Jelisic, Boonserm Kulvatunyou, Scott Nieman, Hakju Oh, Zoran Marjanovic
Business context has a potential to become a powerful mechanism for interoperable usage and efficient maintenance of message standards. In the literature, there...
Seulki Cho, Son T. Le, Curt A. Richter, Arvind Balijepalli
We demonstrate that single-gated, commercially-sourced, field-effect transistors (FETs) operated with a lock- in amplifier (LIA) under closed-loop control can...
To reduce the possibility of fraudulent activity and market manipulation, the world's major stock exchanges require every clock involved in a stock market...
Mattias Kruskopf, Dinesh K. Patel, Chieh-I Liu, Albert Rigosi, Randolph Elmquist, Yicheng Wang, Stefan Bauer, Yefei Yin, Klaus Pierz, Eckard Pesel, Martin Goetz, Jurgen Schurr
The frequency dependence of the quantized Hall resistance at alternating current results from capacitive losses inside the sample as well as between the sample...
Randolph E. Elmquist, Mattias Kruskopf, Dinesh K. Patel, I Fan Hu, Chieh-I Liu, Albert F. Rigosi, Alireza R. Panna, Shamith U. Payagala, Dean G. Jarrett
Quantized Hall array resistance standards (QHARS) span values from 100 (ohm) to 1 M(ohm) and demonstrate precision approaching that of single devices. This...
David C. Deisenroth, Leonard M. Hanssen, Sergey Mekhontsev
Additive manufacturing involving layer-wise selective laser melting of a powder material, or laser powder bed fusion (LPBF), is a fast-growing industry. At the...
Abstract Many machine learning algorithms examine large amounts of data to discover insights from hidden patterns. Testing these algorithms can be expensive...
Valeriy V. Yashchuk, Sergey Babin, Stefano Cabrini, Weilun Chao, Ulf Griesmann, Ian Lacey, Stefano Marchesini, Keiko Munechika, Carlos Pina-Hernandez, Allen L. Roginsky
Recently, a technique for calibrating the modulation transfer function (MTF) of a broad variety of metrology instrumentation has been demonstrated. This...
Takehiko Oe, Shamith U. Payagala, Dean G. Jarrett, Nobu-Hisa Kaneko
DC high resistance measurement capability has been evaluated using a NMIJ traveling dual source bridge between NIST and NMIJ. The NMIJ bridge determines the...
Dean G. Jarrett, Shamith U. Payagala, Ryan P. Fitzgerald, Denis E. Bergeron, Jeffrey T. Cessna, Charles J. Waduwarage Perera, Neil M. Zimmerman
A system for the calibration of electrometers that measure currents from ionization chambers is described. The calibration system uses a 1 GΩ standard resistor...
Dimitrios Georgakopoulos, Ilya F. Budovsky, Samuel Benz
We have extended the voltage range of the Josephson arbitrary waveform synthesizer from 1 mV down to 1 μV at frequencies from 60 Hz to 1 kHz to calibrate...
Shamith U. Payagala, Alana M. Dee, Dean G. Jarrett
The adapted Wheatstone bridge technique has been utilized at National Institute of Standards and Technology (NIST) and other National Metrology Institutes (NMIs...
Takehiko Oe, Alireza R. Panna, Randolph E. Elmquist, Dean G. Jarrett, Yasuhiro Fukuyama, Nobu-Hisa Kaneko
We have fabricated 129 kΩ and 1 MΩ quantum Hall array devices using GaAs/AlGaAs heterostructures and their quantized Hall resistance plateaus were precisely...
Alain Rufenacht, Anna E. Fox, Grace E. Butler, Charles J. Burroughs, Paul D. Dresselhaus, Robert E. Schwall, Stefan Cular, Samuel P. Benz
This paper presents precision measurements with a prototype cryogen-liquid-free DC Josephson voltage standard that produces a 1 V maximum output. Its cryostat...
Hansong Xu, Wei Yu, Xing Liu, David W. Griffith, Nada T. Golmie
Industrial Internet of Things (IIoT) is predicted to drive the fourth industrial revolution through massive interconnection of industrial devices, such as...