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Displaying 27726 - 27750 of 73830

Regarding Electric Energy Savings, Power Factors, and Carbon Footprints: A Primer

October 31, 2009
Author(s)
Martin Misakian, Thomas L. Nelson, William E. Feero
A short primer is presented which describes the underlying physical theory of certain devices that reduce the current drawn from power distribution lines by improving the power factor of residential electric circuits. A brief discussion is provided of the

10-GHz Self-Referenced Optical Frequency Comb

October 30, 2009
Author(s)
Albrecht Bartels, Dirk Heinecke, Scott Diddams
For a decade the femtosecond laser based frequency comb has played a key role in high precision optical frequency metrology.While often referred to as a precise optical frequency ruler, its tick marks are in fact too densely spaced for direct observation

Getting Closer to Redefining the Kilogram

October 30, 2009
Author(s)
Zeina J. Kubarych
A redefinition to replace the last remaining artifact based SI unit, the kilogram, may occur as early as 2011. This article presents a short summary of the status of current international efforts focused on the redefinition and the internationally agreed

IMEP-28: Total Arsenic, Cadmium, Lead and Mercury in Food Supplements

October 30, 2009
Author(s)
Lane C. Sander, Stephen E. Long, Steven J. Christopher, Russell D. Day, Karen E. Murphy, Ines Baer, Beatriz de la Calle, Inge Verbist, Danny Vendelbo, Hakan Emteborg, Philip Taylor
The Institute for Reference Materials and Measurements (IRMM) of the Joint Research Centre (JRC), a Directorate-General of the European Commission, operates the International Measurement Evaluation Programme IMEP. It organises interlaboratory comparisons

Interoperability and the DMIS experience

October 30, 2009
Author(s)
John A. Horst
Because they enable true interoperability, information exchange standards can help manufacturers reduce cost and improve product quality, but only if the standards are developed and implemented correctly. We will answer questions manufacturers and

IREX I: Performance of Iris Recognition Algorithms on Standard Images

October 30, 2009
Author(s)
Patrick J. Grother, Elham Tabassi, George W. Quinn, Wayne J. Salamon
The IREX program supports the development of interoperable iris imagery for use in high performance biometric applications. The IREX evaluation, was conducted in cooperation with the iris recognition industry to demonstrate that standardized image formats

NIST High Resolution X-Ray Diffraction Standard Reference Material: SRM 2000

October 30, 2009
Author(s)
Donald A. Windover, David L. Gil, Albert Henins, James P. Cline
NIST recently released a standard reference material (SRM) for the calibration of high resolution X-ray diffraction (HRXRD) instruments. HRXRD is extensively used in the characterization of lattice distortion in thin single, epitaxial crystal layers on

Ontological Product Modeling for Collaborative Design

October 30, 2009
Author(s)
Conrad E. Bock, XuanFang Zha, Hyo W. Suh, Jae H. Lee
This paper presents a product modeling language for collaborative design that has the benefits of ontology and expanded capabilities in conventional product modeling. The proposed approach uses ontology to increase flexibility and accuracy in combining

Quantum walk on a line for a trapped ion

October 30, 2009
Author(s)
Peng Xue, Barry Sanders, Dietrich Leibfried
We show how a quantum walk can be experimentally realized for a single trapped ion and how to interpolate between the quantum and random walk by randomizing the phase of a generalized Hadamard coin flip. The signature of the quantum walk is manifested not

Report on the Key Comparison CCPR K2.a-2003

October 30, 2009
Author(s)
Yoshihiro Ohno, Steven W. Brown, Thomas C. Larason
Under the framework of Mutual Recognition Arrangement (MRA) for national measurements standards and for calibration and measurement certificates issued by National Metrology Institutes (NMIs) signed in 1999, an international comparison of spectral

Poiseuille flow and drop circulation in microchannels

October 29, 2009
Author(s)
Steven D. Hudson
Microfluidics aims to control precisely the transport of fluids and suspended particles or drops. Here we calculate two characteristics of interest in rectangular microchannels, as a function of the cross-sectional aspect ratio. First, we present a

Determination of Perfluorinated Alkyl Acid concentrations in Human Serum and Milk Standard Reference Materials

October 28, 2009
Author(s)
Jennifer M. Lynch, Antonia M. Calafat, Kayoko Kato, Mark E. Ellefson, William K. Reagen, Mark Strynar, Steven G. O'Connell, Craig M. Butt, Scott Mabury, Jeff Small, D.C.G. Muir, Stefan D. Leigh, Michele M. Schantz
Standard Reference Materials (SRMs) are homogeneous, well-characterized materials that are used to validate measurement methods and are critical in improving data quality. Disagreements in perfluorinated alkyl acid (PFAA) concentrations measured in
Displaying 27726 - 27750 of 73830
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