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3D stereo depth sensors have a variety of applications, including sensing for autonomous vehicles, reverse engineering, and manufacturing automation. The performance of these sensors can be affected by various factors, such as sensor construction, sensor
3D stereo depth sensors have a variety of applications, including sensing for autonomous vehicles, reverse engineering, and manufacturing automation. The performance of these sensors can be affected by various factors, such as sensor construction, sensor
David La Mantia, Mingxin Lei, Nikunjkumar Prajapati, Noah Schlossberger, Matthew Simons, Christopher Holloway, Julia Scherschligt, Stephen Eckel, Eric Norrgard
We demonstrate a blackbody radiation thermometer based on optically excited rubidium atoms in a vapor cell. Operating as a calibrated contact thermometer from 308K to 343 K, we realize temperature uncertainty as low as 0.04 %, and statistical temperature
Veruska Malave, Newell Moser, Edward Garboczi, Mark McLinden, Jason Widegren, Christopher Suiter
Our earlier work demonstrated that nuclear magnetic resonance (NMR) spectroscopy is a viable technique for in situ analysis of vapor–liquid equilibria (VLE) of fluid mixtures and that inserting a capillary into the NMR sample tube allows the simultaneous
David Deisenroth, Jordan Weaver, Sergey Mekhontsev, Steven Grantham, Shawn P. Moylan
One of key parameters of additive manufacturing by laser powder bed fusion of metal parts (PBF-LB/M) is the power density distribution (PDD) of the process laser beam. This paper describes the methods used to measure the beam PDD, discussing well
Balasubramanian Muralikrishnan, Katharine Shilling, Vincent Lee, Olga Ridzel, Glenn Holland, John Villarrubia
We describe a method to calibrate angular positioning errors of a rotation stage using a laser tracker (LT), a plane mirror mounted on the stage, and stationary registration nests placed around the stage. Our technique involves determining the direction of
Patrick McArdle, Bradley Pelz, Christopher Yung, Nathan Tomlin, John Lehman, Michelle Stephens
In this work we describe the use of a THz quantum cascade laser (QCL) to perform bi-directional reflectance distribution (BRDF) measurements. In particular we are interested in the reflectance properties of ultra-black absorbers for use in detector devices
Formulas are presented for the leading term in second-order diffraction effects on optical radiometric measurements. The results are compared to those of numerical calculations. The results of this work can be used to facilitate streamlined improvements in
Through the teaching of the International System of Units (SI) principles, Science, Technology, Engineering, and Mathematics (STEM) educators create a ripple effect, cultivating the next generation of metrologists. This, in turn, builds the solid
Sara Rostampour, Song-Syun Jhang, Jung Kai Hsu, Rachel Cook, Yuejin Li, chunlei fan, Li Piin Sung
Microplastics pose a significant environmental threat, and understanding their sources and generation mechanisms is crucial for mitigation efforts. This study investigates the effects of ultraviolet intensity, temperature, and relative humidity on the
Sina Ghadi, Xiaobo Chen, Nicholas Tomasello, Nicholas Derimow, Srikanth Rangarajan, Guangwen Zhou, Scott Schiffres
Assessment of metal powders in powder bed additive manufacturing is crucial, as the quality of the powders significantly impacts the final printed parts. This study introduces a novel technique to characterize metal powders by analyzing changes in their
Michael Link, Megan Claflin, Christina Cecelski, Ayomide Akande, Delany Kilgour, Paul Heine, Matthew Coggon, Chelsea Stockwell, Andrew Jensen, Jie Yu, Han Huyhn, Jenna Ditto, Carnsten Warneke, William Dresser, Keighan Gemmell, Spiro Jorga, Rileigh Robertson, Joost de Gouw, Timothy Bertram, Jonathan Abbatt, Nadine Borduas-Dedekind, Dustin Poppendieck
Proton-transfer-reaction mass spectrometry (PTR-MS) using hydronium ion (H3O+) ionization is widely used for the measurement of volatile organic compounds (VOCs) both indoors and outdoors. H3O+ ionization, as well as the associated chemistry in an ion
Abstract In this study, two-phase heat transfer characteristics of cryogenic two-phase nitrogen were investigated. This basic information is required for the sequential design of a mixed refrigerant micro-cryocooler. The effective heat exchanger must be
Paul Patrone, Lili Wang, Sheng Lin-Gibson, Anthony Kearsley
Harmonizing serology measurements (i.e., rendering them interchangeable) is critical for comparing results across different diagnostics platforms, developing associated reference materials, and thereby informing medical decisions. However, the theoretical
Creating a reliable indicator to describe the degradation of ball screws remains a challenging task. Current vibration-based prognostic methods are vulnerable to unknown noise or system disturbances. To address this challenge, our study offers a new method
Perception systems for autonomous vehicles (AVs) require various types of sensors, including light detection and ranging (LiDAR), cameras, and radars, to ensure their robustness in driving scenarios and weather conditions. The data from these sensors are
A new key comparison of the standards for air kerma of the National Institute of Standards and Technology (NIST), USA, and the Bureau International des Poids et Mesures (BIPM) was carried out in the 60Co radiation beam of the BIPM in October 2023. The
John Diulus, Carles Corbella Roca, Feng Yi, David LaVan, Berc Kalanyan, Mark McLean, Lakshmi Ravi Narayan, William Osborn, James Maslar, Andrei Kolmakov
This letter reports on pilot tests of microfabricated nanocalorimeters as a metrology platform for the rapid (sub-100 ms response time) and sensitive detection of neutral radicals generated by reactive cold plasmas, typical in plasma cleaning applications
Qingyu Pan, Fan Zhang, Deepak Vikraman Pillai, Zilong Zhang, Yufeng Zheng, Lang Yuan, Monica Kapoor, John Carsley, Xiaoyuan Lou
In the present work, we studied the grain refinement by adding in situ reactants, pure titanium (Ti) or a combination of Ti and boron (B), and investigated the governing mechanism in Al-Mn-Fe-Si 3104 alloy made by laser direct energy deposition (DED)
The L5 frequency band of GPS features a higher power, higher code rate, and superior performance in GNSS denied or degraded environments. GPS L5 is pre-operational at time of writing with 17 satellites but has sufficient coverage for testing and utilizing
Studying the scission of rodlike micelles under mechanical forces is essential for understanding their stability and behavior in industrial applications. Mechanical stress can fragment these micelles, impacting performance. Investigating this process
Virtual metrology (VM) is an important technology in semiconductor manufacturing that enhances process control, reduces costs, and improves quality. However, as processes become more complicated and process variations increase due to high-mix manufacturing
Balasubramanian Muralikrishnan, Xinsu Lu, Mary Gregg, Katharine Shilling, Braden Czapla
Terrestrial laser scanners (TLS) are portable dimensional measurement instruments used to obtain 3D point clouds of objects in a scene. While TLSs do not require the use of cooperative targets, they are sometimes placed in a scene to fuse or compare data
Juana Williams, John McGuire, Loren Minnich, Gloria Lee, Jan Konijnenburg, Isabel Baucom, Katrice Lippa
The NIST Office of Weights and Measures (OWM) presents its second issue of the 2024 NIST Annual Summary of U.S. Legal Metrology Activities report. This report includes a summary of changes made to NIST Handbook 44 (2024) Specifications, Tolerances and
John McGuire, David Sefcik, Loren Minnich, Isabel Baucom, Katrice Lippa
This 2025 edition includes amendments made through the Committee on Laws and Regulations of the NCWM with technical guidance from the Office of Weights and Measures (OWM) of the NIST and input from weights and measures officials and industry