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pyMCR: A Python Library for Multivariate Curve Resolution Analysis with Alternating Regression (MCR-AR)
No full textpyMCR is a new open-source software library for performing multivariate curve resolution (MCR) analysis with an alternating regression scheme (MCR-AR). MCR is a chemometric method for elucidating measurement signatures of analytes and their relative abundance from a series of mixture measurements, without any knowledge of these values a priori. This software library, written in Python, enables users to perform MCR analysis with their choice of error functions for minimization, constraints, and regressors. Further, users can apply different constraints and regressors for signature and abundance calculations. Finally, this library enables users to develop their own constraints, regressors, and error functions or import them from existing libraries
Tabular Potentials for Monte Carlo Simulation of Supertoroids with Short-Range Interactions
No full textWe describe a methodology for constructing tabular potentials of supertoroids with short-range interactions, which requires the calculation of the volume of overlap of these shapes for many relative positions and orientations. Recent advances in the synthesis of anisotropic colloids have made experimental realizations of such particles feasible and have increased the practical impact of fundamental simulation studies of these families of shapes. This extends our recent work on superquadric potentials to now include a family of ring-like shapes with a hole in the middle. Along with the addition of supertoroids, the ability to make tables for nonidentical particles and particle pairs with multiple, disconnected overlap volumes was added. Using newly developed extensions to a previously published algorithm, we produced tabular potentials for all of these new cases. The algorithmic developments in this work will enable Monte Carlo simulations of a wider variety of shapes to predict thermodynamic properties over a range of conditions
A Black-Box Noninvasive Characterization Method for Industrial Wireless Networks
No full textIndustrial control systems are increasingly using wireless communications to improve monitoring and control of industrial processes. In existing installations, distances and costs for installation often prohibit the running of new cables and conduits, making wireless solutions very attractive. With costs reduced, monitoring of the physical process becomes easier, and operators often desire to extend wireless to include supervisory and feedback control. Feedback control, in particular, requires certain reliability, latency, and performance guarantees that are difficult to characterize. Industrial wireless solutions rarely make quality-of-service measurements available at the control system level. When they do, indicators such as per-link packet success rate are often difficult to translate into meaningful metrics useful to the control system designer. This is especially true for multihop mesh network architectures, where it is difficult to translate link performance to system performance. In this paper, we propose a more useful method to characterize true network latency and reliability of a deployed industrial wireless network without the need for physical layer and link layer performance metrics and design knowledge
Viscosity Measurements of Three Base Oils and One Fully Formulated Lubricant and New Viscosity Correlations for the Calibration Liquid Squalane
No full textThe viscosities of three pentaerythritol tetraalkanoate ester base oils and one fully formulated lubricant were measured with an oscillating piston viscometer in the overall temperature range from 275 K to 450 K with pressures up to 137 MPa. The alkanoates were pentanoate, heptanoate, and nonanoate. Three sensing cylinders covering the combined viscosity range from 1 mPa.s to 100 mPa.s were calibrated with squalane. This required a re-correlation of a squalane viscosity data set in the literature that was measured with a vibrating wire viscometer, with an estimated extended uncertainty of 2 %, because the squalane viscosity formulations in the literature did not represent this data set within its experimental uncertainty. In addition, a new formulation for the viscosity of squalane at atmospheric pressure was developed that represents experimental data from 169.5 K to 473 K within their estimated uncertainty over a viscosity range of more than eleven orders of magnitude. The viscosity of squalane was measured over the entire viscometer range, and the results were used together with the squalane correlations to develop accurate calibrating functions for the instrument. The throughput of the instrument was tripled by a custom-developed LabVIEW application. The measured viscosity data for the ester base oils and the fully formulated lubricant were tabulated and compared with literature data. An unpublished viscosity data set for pentaerythritol tetrapentanoate measured in this laboratory in 2006 at atmospheric pressure from 253 K to 373 K agrees with the new data within their experimental uncertainty and confirms the deviations from the literature data. The density data measured in this project for the three base oils deviate from the literature data in a way that is by sign and magnitude consistent with the deviations of the viscosity data. This points to differences in the sample compositions as the most likely cause for the deviations
Hydrogen-Deuterium Exchange Mass Spectrometry (HDX-MS) Centroid Data Measured between 3.6 degrees C and 25.4 degrees C for the Fab Fragment of NISTmAb
No full textThe spreadsheet file reported herein provides centroid data, descriptive of deuterium uptake, for the Fab Fragment of NISTmAb (PDB: 5K8A) reference material, as measured by the bottom-up hydrogen-deuterium exchange mass spectrometry (HDX-MS) method. The protein sample was incubated in deuterium-rich solutions under uniform pH and salt concentrations between 3.6 degrees C and 25.4 degrees C for seven intervals ranging over (0 to 14,400)s plus a ∞ pseudo s control. The deuterium content of peptic peptide fragments were measured by mass spectrometry. These data were reported by fifteen laboratories, which conducted the measurements using orbitrap and QTOF mass spectrometers. The cohort reported ≈ 78,900 centroids for 430 proteolytic peptide sequences of the heavy and light chains of NISTmAb, providing nearly 100 % coverage. In addition, some groups reported ≈ 10,900 centroid measurements for 77 peptide sequences of the Fc fragment. The instrumentation and physical and chemical conditions under which these data were acquired are documented
Improving Reproducibility in Research: The Role of Measurement Science
No full textWe report on a workshop held 1-3 May 2018 at the National Physical Laboratory, Teddington, U.K., in which the focus was how the world's national metrology institutes might help to address the challenges of reproducibility of research. The workshop brought together experts from the measurement and wider research communities in physical sciences, data analytics, life sciences, engineering, and geological science. The workshop involved 63 participants from metrology laboratories, academia, industry, funding agencies, and publishers. The participants came from the U.K., the United States, Korea, France, Germany, Australia, Bosnia and Herzegovina, Canada, Turkey, and Singapore. Topics explored how good measurement practice and principles could foster confidence in research findings and how to manage the challenges of increasing volume of data in both industry and research
X-ray Metrology for the SemiconductorIndustry Tutorial
No full textThe semiconductor industry is in need of new, in-line dimensional metrology methods with higher spatial resolution for characterizing their next generation nanodevices. The purpose of this short course is to train the semiconductor industry on the NIST-developed critical dimension small angle X-ray scattering (CDSAXS) method. The topics will include both data processing and instrumentation. The short course will also provide an opportunity for discussion of the requirements for CDSAXS and the necessary improvements in X-ray source technology. Expected audience include semiconductor manufacturers, equipment manufacturers, and component manufacturers. The presentations were made at “X-ray Metrology for the Semiconductor Industry” short course at the National Institute of Standards and Technology on Aug.
25, 2016
A Century of WWV
No full textWWV was established as a radio station on October 1, 1919, with the issuance of the call letters by the U.S. Department of Commerce. This paper will observe the upcoming 100th anniversary of that event by exploring the events leading to the founding of WWV, the various early experiments and broadcasts, its official debut as a service of the National Bureau of Standards, and its role in frequency and time dissemination over the past century
Charles L. Wilson
No full textCHARLES L. WILSON
NBS/NIST: 1979-2006
INDUCTED: 2019
Birth: 1942, El Paso, Texas
Death: 2019, Gaithersburg, Maryland
EDUCATION:
University of Texas, BS (Physics), 1964
University of Texas, MS (Physics), 1965
CITATION: For technical excellence in measurement science, pattern recognition, and device modeling; advancing semiconductor manufacturing; and pioneering biometrics
(particularly fingerprint) technology benchmarks and standards, thereby strengthening our Nation’s safety and security.
POSITIONS HELD AT NBS/NIST:
Manager, Device Modeling Group, Semiconductor Electronics Division, Electronics and Electrical Engineering
Laboratory, 1979-1988
Manager, Image Group, Information Access Division, Information Technology Laboratory, 1988-2006
HONORS:
U.S. Department of Commerce Gold Medal (1983 and 2003)
MEMBERSHIPS:
IEEE
Biometrics Subcommittee, National Science and Technology Council, Office of Science and Technology Policy Biometrics Interoperability and Evaluation (interagency working group)
PUBLICATIONS:
More than 70 publications and 2 patents including:
Wilson, C.L. and Blue, J.L., "Two-dimensional Finite Element Charge-sheet Model of a Short-channel MOS
Transistor", Solid-State Electronics, Vol. 25, 461-477 (1982)
Wilson, Charles L., et al., The First Census Optical Character Recognition Systems Conference, NISTIR 4912
(January 1992)
Wilson, C.L., Candela, G.T., and Watson, C.I., "Neural Network Fingerprint Classification", Journal of Artificial
Neural Networks, Vol. 1, No. 2 (1993)
Chellappa, R., Wilson, C.L., and Sirohey, S., "Human and Machine Recognition of Faces: A Survey",
Proceedings of the IEEE, Vol. 83, No. 5, 705–740 (May 1995)
Tabassi, E. and Wilson, C.L., "A Novel Approach to Fingerprint Image Quality", IEEE International Conference on Image Processing, Vol. 2, No. 2, 37-40, Genoa, Italy (2005
William R. Ott
No full textWILLIAM R. OTT
NBS/NIST: 1968-2011
INDUCTED: 2019
Birth: 1942, Philadelphia, Pennsylvania
EDUCATION:
St. Joseph’s University, BS (Electronic Physics), 1963 University of Pittsburgh, PhD (Physics), 1968
CITATION: For exceptional leadership of NIST Laboratory programs, the NIST Distinguished Speakers Colloquium Series, and establishment of the NIST Presidential Early Career Award for Scientists and Engineers and Scientist Emeritus programs.
POSITIONS HELD AT NBS/NIST:
NAS/NRC Postdoctoral Research Associate, Plasma Spectroscopy Section, Atomic Physics Division, Institute
for Basic Standards (1968-1970)
Research Physicist, Atomic and Plasma Radiation Division, Center for Radiation Research (CRR), National
Measurement Laboratory (NML), 1970-1980
Scientific Assistant to the NML Director, 1980-1981
Program Analyst, Office of the NBS Director, 1982-1983
Chief, Radiation Physics Division, CRR, NML, 1983-1986
Chief, Electron and Optical Physics Division, CRR, NML, 1987-1989
Deputy Director, Center for Atomic, Molecular, and Optical Physics, NML, 1988-1990
NIST Liaison, SPIE International Society for Optical Engineering, 1988-1993
NIST Liaison, SDI/BMDO Missile Defense Program, 1988-2011
Deputy Director, Physics Laboratory, 1990-2010
NIST Representative, Interagency Subcommittee on Budget Priorities, CFS/NSTC, 1994
Deputy Director for Measurement Science, Physical Measurement Laboratory (PML), 2010-2011
Guest Researcher, PML, 2011-Present
HONORS:
President, NBS Employees Association/SEBA (1974)
U.S. Department of Commerce Silver Medal (1976)
Alexander von Humboldt Research Fellowship, Universität Düsseldorf, Germany (1977-1978)
Fellow, Optical Society of America (1990)
U.S. Department of Commerce Gold Medal (2002)
Physical Science Award and Fellow, Washington Academy of Sciences (2004)
Fellow, American Physical Society (2007)
U.S. Department of Commerce Meritorious Executive Rank Award (2008)
MEMBERSHIPS:
Optical Society of America
Washington Academy of Sciences
American Physical Society
PUBLICATIONS:
More than 50 publications including:
Ott, W.R., Fieffe-Prevost, P., and Wiese, W.L., "VUV Radiometry with Hydrogen Arcs: 1. Principle of the
Method and Comparisons with Blackbody Calibrations from 165 nm to 360 nm", Appl. Opt. 12, 1618 (1973) Ott, W.R., Behringer, K., and Gieres, G., "VUV Radiometry with Hydrogen Arcs: 2. The High Power Arc as an
Absolute Standard of Spectral Radiance from 124 nm to 360 nm", Appl. Opt. 14, 2121 (1975)
Bridges, J.M. and Ott, W.R., "VUV Radiometry with Hydrogen Arcs: 3. The Argon Mini-Arc as a New
Secondary Standard of Spectral Radiance", Appl. Opt. 16, 367 (1977)
Saunders, R.D., Ott, W.R., and Bridges, J.M., "Spectral Irradiance Standard for the Ultraviolet: The Deuterium
Lamp", Appl. Opt. 17, 593 (1978)
Ott, W.R., Bridges, J.M., and Klose, J.Z., "Vacuum Ultraviolet Spectral Irradiance Calibrations: Method and Applications", Opt. Letters 5, 225 (1980