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NIST Authors in Bold

Displaying 851 - 875 of 2606

The Design of the NEW NIST-4 Watt Balance

August 24, 2014
Author(s)
Leon S. Chao, Stephan Schlamminger, Frank C. Seifert, Yusi A. Cao, Darine El Haddad, David B. Newell, Jon R. Pratt
The design of the new permanent-magnet driven watt balance and novel mechanical features will demonstrate the high-precision capabilities of a large complex mass measurement system with expected overall uncertainties on the order of 3 parts in 10^8.

Stochastic Regression Modeling of Chemical Spectra

August 14, 2014
Author(s)
Anthony J. Kearsley, William E. Wallace, Yutheeka Gadhyan
A stochastic regression method has been developed that decomposes chemical spectra into separate contributions from signal and from noise. The numerical results of regressing in this way on sample spectra are presented. The results suggest that this

The Half-Life of 209Po : Revisited

August 13, 2014
Author(s)
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
A substantial 25 % error in the then known and accepted (102  5) year half-life of 209Po was reported on in 2007. This error was detected from decay data from two separate primary standardizations of a 209Po solution standard, which were performed

Speckle phase noise in coherent laser ranging: fundamental precision limitations

August 8, 2014
Author(s)
Esther Baumann, Jean-Daniel Deschenes, Fabrizio R. Giorgetta, William C. Swann, Ian R. Coddington, Nathan R. Newbury
Frequency-modulated continuous-wave laser detection and ranging (FMCW LADAR) measures the range to a surface through coherent detection of the backscattered light from a frequency-swept laser source. The ultimate limit to the range precision of FMCW LADAR

Construction of a watt balance with the aim to realize the kilogram at the National Institute of Standards and Technology

August 1, 2014
Author(s)
Darine El Haddad, Leon Chao, Frank Seifert, David B. Newell, Jon R. Pratt, Stephan Schlamminger
A redefinition of the International System of Units, the SI, is impending and could occur as early as 2017. After redefinition a means to realize the unit of mass is required. A watt balance is a promising device to realize the unit of mass at the kilogram

In Search of Better Pressure Standards

August 1, 2014
Author(s)
Jay H. Hendricks, Jacob E. Ricker, Patrick F. Egan, Gregory F. Strouse
Based on highly accurate optical interferometry and fundamental quantum calculations, researchers at the National Institute of Standards and Technology (NIST) in the US are developing an improved definition of the SI unit for pressure that will consign the

Transportation Effect of the Ni-Cr Based Metal-Foil Standard Resistors in the Trilateral Comparison Pilot Study between KRISS, NIST and NMIJ

August 1, 2014
Author(s)
Randolph E. Elmquist, Nobu-hisa Kaneko, Takehiko Oe, Wan-Seop Kim, Dong Hun Chae, Marlin E. Kraft
This paper describes a study on the transportation effect using four 100 Ω standard resistors of a new construction. All resistors have been transported by air: two of the resistors in hand-carried luggage and the other two by normal air freight. The

Performance Metrics for Evaluating Object and Human Detection and Tracking Systems

July 30, 2014
Author(s)
Afzal A. Godil, Roger Bostelman, William P. Shackleford, Tsai H. Hong, Michael O. Shneier
In this report, we provide an overview of various performance evaluation metrics for object detection and tracking for robot safety applications in smart manufacturing. We present four different types of performance evaluation metrics based on detection

Dielectric characterization by microwave cavity perturbation corrected for non-uniform fields

July 23, 2014
Author(s)
Nathan D. Orloff, Jan Obrzut, Christian J. Long, Thomas F. Lam, James C. Booth, David R. Novotny, James A. Liddle, Pavel Kabos
The non-uniform fields that occur due to the slot in the cavity through which the sample is inserted and those due to the sample geometry itself decrease the accuracy of dielectric characterization by cavity perturbation at microwave frequencies. To

Advanced phasemeter for deep phase modulation interferometry

July 21, 2014
Author(s)
Thomas Schwarze, Oliver Gerberding, Felipe Guzman, Gerhard Heinzel, Karsten Danzmann
We present the development of an advanced phasemeter for the deep phase modulation interferometry technique. This technique aims for precise length measurements with a high dynamic range using little optical hardware. The advanced phasemeter uses fast ADCs

Electronic Structure and Band Alignment at Epitaxial Co3O4/SrTiO3 Heterojunction

July 21, 2014
Author(s)
Liang Qiao, Wei Li, Haiyan xiao, Harry M. Meyer, Xuelei Liang, Nhan Van Nguyen, Michael D. Biegalski
The electronic properties of solid-solid interfaces play critical roles in a variety of technological applications. Recent advance of film epitaxy and characterization techniques have demonstrated a wealthy of exotic phenomena at interfaces of oxide

Spectral Emissivity Measurements

July 10, 2014
Author(s)
Hiromichi Watanabe, Juntaro Ishii, Hidenobu Wakabayashi, Tomoyuki Kumano, Leonard Hanssen
Chapter 9 describes the wide variety of experimental instrumentation and methods used for spectral emissivity measurements at both ambient and elevated temperatures, along with specific examples of materials studied. There are a number of measurement

Chapter 10: Color and Appearance

July 8, 2014
Author(s)
Maria E. Nadal, Clarence J. Zarobila
This chapter will cover the topic of color and appearance measurements. These measurements essentially constitute a specific example of the measurements described in previous chapters; except that they are performed in the specific wavelength range sensed

Sealed Gravitational Capillary Viscometers for Volatile Liquids

July 7, 2014
Author(s)
Arno R. Laesecke
The evolution of sealed gravitational capillary viscometers for measurements of volatile liquids is reviewed. Two corrections need to be applied to measurements with them: (i) the vapor buoyancy correction and, if coiled capillaries are used, (ii) the

Determination of the Planck constant at the National Institute of Standards and Technology

July 1, 2014
Author(s)
Stephan Schlamminger, Darine El Haddad, Frank C. Seifert, Leon S. Chao, David B. Newell, Ruimin Liu, Richard L. Steiner, Jon R. Pratt
In 2013, a new measurement of the Planck constant h was performed using a watt balance at the National Institute of Standards and Technology (NIST). The value is h=6.626 069 79(30) x 10^{-34} J s. The relative standard uncertainty of this determination is

New Developments in the NIST Infrared Optical Properties of Materials Program

July 1, 2014
Author(s)
Leonard M. Hanssen, Sergey Mekhontsev, Jinan Zeng, John H. Burnett
The Infrared Optical Properties of Materials program in the Sensor Science Division at the National Institute of Standards and Technology (NIST) continues to upgrade its capabilities to provide comprehensive coverage of measurable infrared optical

State of the Art Raman Techniques for Biological Applications

July 1, 2014
Author(s)
Angela R. Hight Walker, Alasdair Rae, Rainer Stosch, Petr Klapetek, Debdulal Roy
Raman spectroscopy is a powerful tool for the elucidation of qualitative and quantitative information from biological systems and has huge potential in areas such as biotechnologies, drug discovery, agro-chemical research and clinical diagnostics. This

A nonlinearity in permanent-magnet systems used in watt balances

June 25, 2014
Author(s)
Shisong Li, Stephan Schlamminger, Jon R. Pratt
In watt balances that employ permanent magnet systems to generate the magnetic flux the effects of the weighing current on the magnet systems can generate a systematic bias that can lead to an error in the result if not accounted for. In this article a
Displaying 851 - 875 of 2606