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Displaying 26 - 50 of 132

Statistical Methods for Change-Point Detection in Surface Temperature Records

September 12, 2013
Author(s)
Adam L. Pintar, Antonio M. Possolo, Nien F. Zhang
We describe several statistical methods to detect possible change-points in a time series of values of surface temperature measured at a meteorological station, and to assess the statistical significance of such changes, taking into account the natural

SIM.EM-S5 Voltage, Current and Resistance Comparison

June 1, 2012
Author(s)
Harold Sanchez, Lucas Di Lillo, Gregory Kyriazis, Rodrigo Ramos, Randolph Elmquist, Nien F. Zhang
This paper reports the results of the second Interamerican Metrology System (SIM) comparison on calibration of digital multimeters, performed for strengthening the interaction among National Metrology Institutes (NMIs) and for establishing the degree of

A Bayesian Statistical Model for Hybrid Metrology to Improve Measurement Accuracy

July 31, 2011
Author(s)
Richard M. Silver, Nien F. Zhang, Bryan M. Barnes, Jing Qin, Hui Zhou, Ronald G. Dixson
We present a method to combine measurements from different techniques that reduces uncertainties and can improve measurement throughput. The approach directly integrates the measurement analysis of multiple techniques that can include different

Nested Uncertainties and Hybrid Metrology to Improve Measurement Accuracy

April 18, 2011
Author(s)
Richard M. Silver, Nien F. Zhang, Bryan M. Barnes, Hui Zhou, Jing Qin, Ronald G. Dixson
In this paper we present a method to combine measurement techniques that reduce uncertainties and improve measurement throughput. The approach has immediate utility when performing model-based optical critical dimension measurements. When modeling optical

Linking the Results of CIPM and RMO Key Comparisons with Linear Trends

June 30, 2010
Author(s)
Nien F. Zhang
A statistical approach to link the results of interlaboratory comparisons with linear trends is proposed. This approach can be applied to the case that the comparisons have the same nominal values or of a same magnitude. The degrees of equivalence between

Certification of Drugs of Abuse in a Human Serum Standard Reference Material: SRM 1959

March 24, 2010
Author(s)
Susan S. Tai, Jocelyn L. Prendergast, Lorna T. Sniegoski, Michael J. Welch, Karen W. Phinney, Nien F. Zhang
A new Standard Reference Material (SRM) for drugs of abuse in human serum (SRM 1959) has been developed. SRM 1959 is a frozen human serum material fortified with seven drugs of abuse, benzoylecgonine (BZE), methadone (METH), methamphetamine (MAMP)

Angle-resolved Optical Metrology using Multi-Technique Nested Uncertainties

August 15, 2009
Author(s)
Richard M. Silver, Bryan M. Barnes, Hui Zhou, Nien F. Zhang, Ronald G. Dixson
This paper introduces recent advances in scatterfield microscopy using improved normalization and fitting procedures. Reduced measurement uncertainties are obtained through the use of more accurate normalization procedures in combination with better

Three Statistical Paradigms for the Assessment and Interpretation of Measurement Uncertainty

January 12, 2009
Author(s)
William F. Guthrie, Hung-Kung Liu, Andrew L. Rukhin, Blaza Toman, Chih-Ming Wang, Nien F. Zhang
The goals of this chapter are to present different approaches to uncertainty assessment from a statistical point of view and to relate them to the methods that are currently being used in metrology or are being developed within the metrology community. The

SIM Comparison of DC Resistance Standards at 1 {O}, 1 M{O}, and 1 G{O}

January 1, 2009
Author(s)
Dean G. Jarrett, Randolph E. Elmquist, Nien F. Zhang, Alejandra Tonina, M Porfiri, Janice Fernandes, H Schechter, Daniel Izquierdo, C Faverio, Daniel Slomovitz, Dave Inglis, Kai Wendler, Felipe Hernandez-Marquez, B Rodriguez
A set of regional comparisons of dc resistance standards at the nominal values of 1 {Ω}, 1 M {Ω}, and 1 G {Ω} has recently been completed in the Sistema Interamericano de Metrogia (SIM) region. The motivation, design, standards, and results of these