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Jon C. Geist, Muhammad Y. Afridi, Craig McGray, Michael Gaitan
Cross-sensitivity matrices are used to translate the response of three-axis accelerometers into components of acceleration along the axes of a specified coordinate system. For inertial three-axis accelerometers, this coordinate system is often defined by
Vyacheslav B. Podobedov, George P. Eppeldauer, Thomas C. Larason
A new night vision goggles (NVG) gain definition for the calibration process is proposed and evaluated. This definition is based on the radiance measurements at the input and output of the NVG. In contrast to the old definition which uses a non-
Matthias J. Merzkirch, Louise A. Ahure Powell, Timothy J. Foecke
Numerical models based on cohesive zones are usually used to model and simulate the mechanical behavior of laminated carbon fiber reinforced polymers (CFRP) in automotive and aerospace applications. The codes of these models require different interlaminar
Critical dimension atomic force microscopy (CD-AFM) is a measurement technique that uses flared tips and two-dimensional surface sensing to enable scanning of features with near-vertical sidewalls. A major source of uncertainty in metrology with CD-AFM is
Since 2004 standards for calibration of CD-AFM tip width have been available both commercially and through national metrology institutes (NMIs) such as the National Institute of Standards and Technology (NIST) in the United States. There have been inter
Vyacheslav B. Podobedov, George P. Eppeldauer, Leonard M. Hanssen, Thomas C. Larason
We report the upgraded performance of the National Institute of Standards and Technology (NIST) facility for spectral responsivity calibrations of infrared (IR) detectors in both radiant power and irradiance measurement modes. The extension of the
We report the characterization of multiscale 3D structural architectures of novel poly[sulfur- random-(1,3-diisopropenylbenzene)] copolymer-based cathodes for high-energy-density Li−S batteries capable of realizing discharge capacities >1000 mAh/g and long
Thomas Gerrits, John H. Lehman, Alan Migdall, Sae Woo Nam, Igor Vayshenker, Chih-Ming Wang
We report on our progress towards implementing a measurement service aimed at the calibration of single-photon detectors. We present how our calibration is tied to the calibration of our transfer standard optical fiber power meters. We also developed and
We present a method for improving high-insertion-loss measurements with a calibrated vector network analyzer (VNA) requiring only two additional pieces of hardware. By utilizing an amplifier and an attenuator, and measuring wave-parameters rather than
Gustavo Avolio, Dylan Williams, Michael Frey, Sarah B. Streett, Dominique Schreurs, Andrea Ferrero, Michael Dieudonne
We compared three software tools designed for scattering-parameter measurement uncertainty evaluation. These tools propagate uncertainty to calibrated S-parameters by means of a sensitivity analysis. We also validated the sensitivity analysis with Monte
Paul NMN Salipante, Steven D Hudson, James W. Schmidt, John D. Wright
The accurate measurement of flows in microfluidic channels is important for commercial and research applications. We compare the accuracy of flow measurement techniques over a wide range flows. Flow measurements made using holographic microparticle
Gregory W. Vogl, Radu Pavel, Andreas Archenti, Thomas J. Winnard, Matlock M. Mennu, Brian A. Weiss, Alkan Donmez
Machine tools degrade during operations, yet accurately detecting degradation of machine components such as linear axes is typically a manual and time-consuming process. Thus, manufacturers need automated and efficient methods to diagnose the condition of
Matthew J. Connolly, Peter E. Bradley, Andrew J. Slifka, Elizabeth S. Drexler
A gas-pressure chamber has been designed, constructed, and tested at a moderate pressure (3.4 MPa, 500 psi) and has the capability of mechanical loading of steel specimens for neutron scattering measurements. The chamber will allow a variety of in situ
The magnetic suspension mass comparator is a unique system for calibrating kilogram artifacts between vacuum and air. While the MSMC allows for direct vacuum-to-air mass measurements, there are several corrections that need to be accounted. Here, we
Three-axis MEMS accelerometers are typically characterized in terms of their cross-sensitivity matrix. We present an analysis and protocol to characterize them in terms of their intrinsic properties, which we define as the responsivity of each
Christopher L. Holloway, Matthew T. Simons, Joshua A. Gordon, Georg Raithel, dave Anderson
We investigate the relationship between the Rabi frequency ($\Ω_{RF}$, related to the applied electric field) and Autler-Townes (AT) splitting, when performing atom-based radio- frequency (RF) electric (E) field strength measurements using Rydberg states
Marcus H. Mendenhall, Albert Henins, Lawrence T. Hudson, Csilla I. Szabo-Foster, Donald A. Windover, James P. Cline
The structure of the x-ray emission lines of the Cu Kα complex has been remeasured on a newly commissioned instrument, in a manner directly traceable to the Système Internationale definition of the meter. In this measurement, the region from 8000 to 8100
In this paper, the control channel for secondary users in opportunistic spectrum access networks is considered. Given a licensed bandwidth for primary users, we compare the performance of three control-channel schemes: dedicated, underlay, and overlay. The
Ballistic clay is used as a backing material for standards-based ballistic resistance tests for the purposes of providing a measure of the energy transferred to the body when a threat is defeated. However, this material exhibits complex thermomechanical
Roger V. Bostelman, Tsai H. Hong, Steven A. Legowik, Mili Shah
Optical tracking systems are used in a wide range of fields. The market for optical tracking systems has dramatically increased over the past several years to $1.2B revenue in 2014. This paper describes the new ASTM E3064 Standard test method procedures
Prem K. Rachakonda, Balasubramanian Muralikrishnan, Katharine M. Shilling, Geraldine S. Cheok, Vincent D. Lee, Christopher J. Blackburn, Dennis S. Everett, Daniel S. Sawyer
The Dimensional Metrology Group (DMG) at the National Institute of Standards and Technology (NIST) is performing research to support the development of documentary standards within ASTM E57 for the point-to-point performance evaluation of 3D imaging
The National Institute of Standards and Technology has constructed a testbed to measure the performance impact of cybersecurity defenses on Industrial Control Systems (ICS). The testbed allows researchers to emulate real-world industrial manufacturing
Mobile manipulators are being marketed for material handling and other tasks. Manufacturers suggest the stability of the vehicle best when the onboard loading tapers the centroid to the center of the wheelbase as the payload height increases. Experiments