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Conferences

Comparing Interactive Information Retrieval Systems Across Sites: The TREC-6 Interactive Track Matrix Experiment

July 15, 1998

Author(s)

E S. Lagergren, Paul D. Over

This is a case study in the design and analysis of a 9-site TREC-6 experiment aimed at comparing the performance of 12 interactive information retrieval (IR)...

Step Bunching: Influence of Impurities and Solution Flow

July 14, 1998

Author(s)

A A. Chernov, P G. Vekilov, Sam R. Coriell, B T. Murray, Geoffrey B. McFadden

Step bunching results in striations even at relatively early stages of its development and in inclusions of mother liquor at the later stages. Therefore...

Moment-Preserving Modeling With Image Applications

July 6, 1998

Author(s)

Anastase Nakassis, Abdou S. Youssef

Linear least-square modeling is a powerful modeling approach. Optimal piece-wise constant modeling is an important special case. In this paper we will develop a...

Lasers for a Trapped Hg⁺ Optical Frequency Standard

July 6, 1998

Author(s)

B C. Young, D J. Berkeland, F C. Cruz, James C. Bergquist, Wayne M. Itano, David J. Wineland

High-Performance Trapped Hg⁺ Frequency Standards

July 6, 1998

Author(s)

D J. Berkeland, James C. Bergquist, Wayne M. Itano, J D. Miller, B C. Young, David J. Wineland

Experimental Images of the Distribution of Maximal Shear Stresses in Diametrally Compressed MMC and Aluminum Disks

July 5, 1998

Author(s)

Y Yacobi, Geoffrey B. McFadden, E Drescher-Krasicka

Stress mapping techniques by use of an acoustic microscope make use of shear acoustic modes traveling back and forth across the specimen, generated by use of...

International Comparison of Noise-Temperature Measurements at 2, 4, and 12 GHz

July 1, 1998

Author(s)

James P. Randa, J. Achkar, F. I. Buchholz, T. Colard, D. Schubert, M. Sinclair, John Rice, G. S. Williams

We report results of a recent international comparison of thermal noise-power measurements, performed under the auspices of CIPM/CCE. The noise temperatures of...

Numerical Characterization Of The Discharge Coefficient In Critical Nozzles

July 1, 1998

Author(s)

Aaron N. Johnson, Pedro I. Espina, John D. Wright, G E. Mattingly, C L. Merkle

The discharge coefficient in critical nozzles flowing N 2, Ar, CO 2, and H 2 in the Reynolds Number range (2,000 to 22,000) is studied computationally to assess...

Potential Coefficient of Performance Improvements due to Glide Matching With R-407C

July 1, 1998

Author(s)

M E. Marques, Piotr A. Domanski

Potential improvements of the Coefficient of Performance (COP) were investigated for R-407C at cooling and heating conditions of a residential heat pump. The...

Mean Recurrence Intervals of Ultimate Wind Loads

July 1, 1998

Author(s)

Emil Simiu, A N. Heckert, T Whalen

The attention of wind engineers and extreme value climatologists has been focused in the last few decades on estimates of basic windspeeds, that is, wind speeds...

A Guarded Transfer Standard for High Resistance Measurements

July 1, 1998

Author(s)

Dean G. Jarrett

An improved design for a guarded transfer standard in the resistance range 1 M[Ω] to 100 G[Ω] is described. Existing transfer standards and limitations are...

Cryogenic Current Comparator Measurements at 77 K Using Thallium-2223 Thick-film Shields

July 1, 1998

Author(s)

Randolph E. Elmquist

This paper describes resistance ratio measurements using cryogenic current comparator (CCC) devices that operate at 77 K. The magnetic shields are Thallium...

Dependence of Contact Resistance on Current for Good and Bad Ohmic Contacts to Quantized Hall Resistors

July 1, 1998

Author(s)

Kevin C. Lee

Dependence of contact resistance on current has been measured for a large number of ohmic contacts to quantized Hall resistors under quantum Hall effect...

Power and Energy Measurements at NIST

July 1, 1998

Author(s)

Thomas L. Nelson

The NIST calibration service that provides electric energy traceability for the U.S. utility industry is described. Electronic watthour meters, submitted for...

Hydration for a Series of Hydrocarbons

July 1, 1998

Author(s)

Raymond D. Mountain, D Thirumalai

The hydrophobic hydration in a series of hydrocarbons is probed using molecular dynamics simulations. The solutes considered range from methane to octane...

Microcalorimeter EDS Measurements of Chemical Shifts in Fe Compounds

July 1, 1998

Author(s)

David A. Wollman, Dale E. Newbury, Gene C. Hilton, Kent D. Irwin, L L. Dulcie, Norman F. Bergren, John M. Martinis

Chemical shifts result from changes in electron binding energies with the chemical environment of atoms. In x-ray spectra, chemical shifts lead to changes in x...

Glassy Alloys as Potential Bearing Surfaces for Orthopaedic Implants

July 1, 1998

Author(s)

John A. Tesk, C E. Johnson

Glassy (amorphous) metals have some unique properties that may renderthem attractive candidates for the coating of metal-implant bearing surfaces. Metastable...

Optical Computer Aided Tomography for Plasma Uniformity Measurements

July 1, 1998

Author(s)

Eric C. Benck

Optical Computer aided tomography (CAT) is being investigated as a potential in situ diagnostic for measuring plasma uniformity without making assumptions...

Proposed Pressure Standard Based on Capacitance Measurements

July 1, 1998

Author(s)

Michael R. Moldover

We propose to measure the dielectric constant [epsilon] and the thermodynamic temperatue T of helium near 273.16 K and to calculate the pressure p([epsilon],T)...

New Approach for Thermoacoustic Refrigeration

July 1, 1998

Author(s)

J Xiao, Ray Radebaugh

We suggest a new design configuration for thermoacoustic refrigeration that optimises the refrigeration effect caused by both the standing wave and the...

Comparison of Two Josephson Array Voltage Standard Systems Using a Set of Zener References

July 1, 1998

Author(s)

Yi-hua Tang

Metallurgical Evaluation of Prestressed Wire Failures

July 1, 1998

Author(s)

Christopher N. McCowan, Thomas A. Siewert

Prestressed concrete pipe, having an inside diameter of 6.4 m (21 ft), was used to construct a series of siphons for the Central Arizona Project.

Seismic Performance of Masonry Walls With Bed Joint Reinforcement

July 1, 1998

Author(s)

A E. Schultz, R S. Hutchinson, Geraldine Cheok

In-plane cyclic load tests of partially grouted concrete masonry shear walls with bed joint reinforcement are presented. Specimen design and construction, and...

Polarimetric Calibration for Monostatic Radar Systems

July 1, 1998

Author(s)

Lorant A. Muth, Paul D. Domich, B. M. Welsh, A. L. Buterbaugh, B. M. Kent

Calibration standards for radar systems are being developed cooperatively at NIST and DoD measurement facilities. Our goals are to develop standard procedures...