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Design of a Six-DOF Motion Tracking System based on a Stewart Platform and Ball-and-Socket Joints

March 1, 2019

Author(s)

Yong Sik Kim, Shi Hongliang, Nicholas Dagalakis, Jeremy Marvel, Geraldine Cheok

Performance evaluation of industrial robots has been an interesting topic since the 1990s. For this, it is necessary to monitor the motions or activities of industrial robots continuously and correct them subsequently. In this case, an appropriate motion

Switchable detector array scheme to reduce the effect of single-photon detector's deadtime in a multi-bit/photon quantum link

February 25, 2019

Author(s)

Cong Liu, YONGXIONG Ren, Jiapeng Zhao, MOHAMMAD MIRHOSSEINI, SEYED RAFSANJANI, GUODONG XIE, Kai Pang, Zhe Zhao, Long Li, Joshua Bienfang, Alan L. Migdall, Todd Brun, Moshe Tur, Robert Boyd, Alan Wilner

We explore the use of a switchable single-photon detector (SPD) array to reduce the effect of individual SPDs' deadtime for a multi-bit/photon quantum link such as M-orbital-angular-momentum (OAM)-encoded one. Our method uses 􀡺 SPDs with a controllable 􀡹 ×

Defining 'kind of quantity'

February 8, 2019

Author(s)

David W. Flater

The definition of 'kind of quantity' given in the International Vocabulary of Metrology (VIM), 3rd edition, does not cover the historical meaning of the term as it is most commonly used in metrology. Most of its historical meaning has been merged into

Understanding Material Characteristics through Signature Traits from He Pycnometry

January 30, 2019

Author(s)

Huong Giang T. Nguyen, Jarod C. Horn, Matthew Bleakney, Daniel W. Siderius, Laura Espinal

Although helium pycnometry is generally the method of choice for skeletal density measurements of porous materials, few studies have provided a wide range of case studies that demonstrate how to best interpret raw data and perform measurements using it

Model-independent extraction of the shapes and Fourier transforms from patterns of partially overlapped peaks with extended tails

January 1, 2019

Author(s)

Marcus H. Mendenhall, James P. Cline

This work presents a technique for extracting the detailed shape of peaks with extended, overlapping tails in an X-ray powder diffraction pattern. The application we discuss concerns crystallite size broadening, though the technique can be applied to

Frequently Asked Questions About Commercial Hydrogen Vehicle Refueling

December 28, 2018

Author(s)

Juana S. Williams

"Commonly asked questions about hydrogen fuel cell electric vehicles (HFCEV) and hydrogen fuel availability, technology, safety; and the legal metrology requirements and terminology applicable to hydrogen fuel quality, measuring equipment, method of sale

An invisible-stylus-based coordinate measurement system via scaled orthographic projection

December 8, 2018

Author(s)

Joshua A. Gordon, Steven S. Borenstein

We present on a simple yet effective method for creating an invisible stylus from which a non-contact 3-D coordinated measuring system (the PiCMS) is realized. This invisible stylus dubbed a Pixel Probe is created through the orthographic projection of a

EMC and Metrology Challenges for 5G and Beyond

December 7, 2018

Author(s)

Perry F. Wilson, Catherine A. Remley, William F. Young, Camillo A. Gentile, John M. Ladbury, Dylan F. Williams

The potential to connect people and devices anywhere and anytime is driving the development and deployment of a multitude of wireless systems. Wireless connectivity is central to advanced communication technologies, the internet of things (IoT), the smart

CCQM-K131 Low-Polarity Analytes in a Multicomponent Organic Solution: Polycyclic Aromatic Hydrocarbons (PAHs) in Acetonitrile

November 30, 2018

Author(s)

David L. Duewer, Lane C. Sander, Stephen A. Wise

Solutions of organic analytes of known mass fraction are typically used to calibrate the measurement processes used to determine these compounds in matrix samples. Appropriate value assignments and uncertainty calculations for calibration solutions are

CCQM-K95.1 Low-Polarity Analytes in a Botanical Matrix: Polycyclic Aromatic Hydrocarbons (PAHs) in Tea

November 30, 2018

Author(s)

David L. Duewer, Jacolin A. Murray, Laura J. Wood, Stephen A. Wise

Extraction, chromatographic separation, and quantification of low-concentration organic compounds in complex matrices are core challenges for reference material producers and providers of calibration services. Evidence of successful participation in formal

NIST Handbook 150-8, NVLAP Acoustical Testing Services

November 19, 2018

Author(s)

Kari K. Harper

NIST Handbook 150-8 presents technical requirements and guidance for the accreditation of laboratories under the National Voluntary Laboratory Accreditation Program (NVLAP) Acoustical Testing Services program. It is intended for information and use by

Evaluation of electronic energy meter measurement error for circuits with switching power converters

October 22, 2018

Author(s)

Dhananjay Anand

A recent study performed by the authors in [1] has shown that some electronic energy meters are susceptible to electromagnetic interference resulting in significant errors in the energy measurement. The authors have proposed that this interference is

AC-DC Difference of a Thermal Transfer Standard from a Pulse-driven Josephson Voltage Standard at NRC

October 21, 2018

Author(s)

Nathan Flowers-Jacobs, Alain Rufenacht, Ghislain Granger

An upgraded pulse-driven AC Josephson Voltage Standard system at the National Research Council Canada allows the generation of quantum-accurate root-mean-square voltages up to 1 V at frequencies down to 10 Hz. The system is used to determine the AC-DC

Characterization of a Dual Josephson Impedance Bridge

October 21, 2018

Author(s)

Nathan Flowers-Jacobs, Blaise Jeanneret, Frederic Overney, Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel P. Benz

This paper describes a dual Josephson impedance bridge capable of comparing any two impedances, that is, with any amplitude ratio and relative phase, over a wide range of frequency. A new, more compact, design has been achieved by mounting the two

Tip on Tip Imaging and Self-Consistent Calibration for Critical Dimension Atomic Force Microscopy: Refinements and Extension to Second Lateral Axis

October 19, 2018

Author(s)

Ronald G. Dixson

One type of atomic force microscopy (AFM) used for critical dimension (CD) metrology is commonly referred to as critical dimension atomic force microscopy (CD-AFM); it uses flared tips and two-dimensional surface sensing to enable scanning of features with

Calibration Fluids and Calibration Equations: How Choices May Affect the Results of Density Measurements Made with U-Tube Densimeters

October 9, 2018

Author(s)

Stephanie L. Outcalt

Data on the calibration fluids water and toluene individually, and the combination of those two sets of data, were correlated with two different equations (resulting in six sets of calibration equation parameters) to analyze data measured with a vibrating

Nondestructive shape process monitoring of three-dimensional high aspect ratio targets using through-focus scanning optical microscopy Optical Microscopy

September 27, 2018

Author(s)

Ravikiran Attota, Hyeonggon Kang, Keana C. Scott, Richard A. Allen, Andras Vladar, Bunday Benjamin

Low-cost, high-throughput and nondestructive metrology of truly three-dimensional (3-D) targets for process control/monitoring is a critically needed enabling technology for high-volume manufacturing (HVM) of nano/micro technologies in multi-disciplinary

Quantities of marine debris ingested by sea turtles: Global meta-analysis highlights need for standardized data reporting methods and reveals relative risk

September 25, 2018

Author(s)

Jennifer M. Lynch

Marine debris ingestion is a threat to marine organisms. Previous reviews call for standardization and highlight biases in the literature, yet none thoroughly describe improvements needed at the data reporting stage. This review explains the consequences

Improving Measurement for Smokestack Emissions - Workshop Summary

September 21, 2018

Author(s)

Rodney A. Bryant, Aaron N. Johnson, John D. Wright, Tamae M. Wong, James R. Whetstone, Michael R. Moldover, Iosif I. Shinder, Scott Swiggard, Chris Gunning, David Elam, Tom Martz, Eric Harman, David Nuckols, Liang Zhang, Woong Kang, Salvator Vigil

The complex flow conditions inherent in power plant smokestacks make accurate flow measurements challenging, which in turn limits the accuracy of hazardous emissions measurements. While stack composition measurements are assessed daily via comparison to a

Spherical Test Objects for Hand-held Metal Detector Characterization

September 12, 2018

Author(s)

Nicholas G. Paulter Jr., Donald R. Larson, John A. Ely

Measuring the detection performance of metal detectors (hand-worn, hand-held, and walk-through models) is based on the observation of an alarm indication (light, sound, vibration) given by the metal detector when a threat or test object is present. These

Mechanical characterization of planar springs for compact radiation pressure power meters

September 7, 2018

Author(s)

Alexandra B. Artusio-Glimpse, Ivan Ryger, Paul A. Williams, Kyle A. Rogers, Daniel W. Rahn, Andrew J. Walowitz, John H. Lehman

Counter to conventional methods of measuring laser optical power, radiation pressure-based power meters operate by reflection rather than absorption. This provides an opportunity for in situ, non-destructive total beam power measurement. Compact radiation

Comparing Aerosol Refractive Indices Retrieved from Full Distribution and Size- and Mass- Selected Measurements

September 1, 2018

Author(s)

James G. Radney, Christopher D. Zangmeister

Refractive index retrievals (also termed inverse Mie methods or optical closure) have seen considerable use as a method to extract the refractive index of aerosol particles from measured optical properties. Retrievals of an aerosol refractive index use two

Determining Carbon Fiber Composite Loading with Flip-Chip Measurements to 110 GHz

September 1, 2018

Author(s)

Nina P. Basta, Aaron Hagerstrom, Jasper A. Drisko, James Booth, Edward Garboczi, Christian Long, Nathan Orloff

— Electrical properties of materials are a necessary part of any circuit design. With emerging applications at millimeter- wave frequencies, there is a need to characterize new materials before they come to market. At frequencies below about 67 GHz, it is

On Algorithms and Heuristics for Constrained Least-Squares Fitting of Circles and Spheres to Support Standards

August 28, 2018

Author(s)

Craig M. Shakarji, Vijay Srinivasan

Constrained least-squares fitting has gained considerable popularity among national and international standards committees as the default method for establishing datums on manufactured parts. This has resulted in the emergence of several interesting and

TOWARDS MAKING NIST-QUALITY MEASUREMENTS OF RADIATION AND RADIOACTIVITY USING COMMERCIAL ANALYTICAL INSTRUMENTS

August 25, 2018

Author(s)

Ryan P. Fitzgerald, Denis E. Bergeron

Precision measurements of radiation and radioactivity are carried out in laboratories across the US for many important applications: to make sure the tens of millions of Americans who undergo cancer treatment or nuclear stress tests every year are given