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NIST Authors in Bold

Displaying 29651 - 29675 of 74178

Measuring Optical Tunneling Times using a Hong-Ou-Mandel Interferometer.

September 23, 2008
Author(s)
Sergey Polyakov, Alan L. Migdall, Paul D. Lett, David Papoular, Pierre Clade, Colin McCormick
We report a prediction for the delay measured in an optical tunneling experiment using Hong-Ou-Mandel (HOM) interference, taking into account the Goos-Hanchen shift generalized to frustrated total internal reflection situations. We precisely state

Ultra-high resolution alpha particle spectroscopy using calorimetry

September 23, 2008
Author(s)
Robert D. Horansky, Joel N. Ullom, James A. Beall, Gene C. Hilton, Kent D. Irwin, Don Dry, Beth Hastings, Stephen Lamont, Clifford R. Rudy, Michael W. Rabin
Calorimetry has been used since the late 1700?s to measure the heat output of physical processes ranging from chemical reactions to the respiration of organisms . Calorimetry is performed by measuring the temperature change caused by heat release into a

Allan Variance of Time Series Models of Measurement Data

September 22, 2008
Author(s)
Nien F. Zhang
The uncertainty of the mean of autocorrelated measurements from a stationary process has been discussed in the literature. However, when the measurements are from a non-stationary process, how to assess their uncertainty remains unresolved. Allan variance

Does the Angle of a Fingerprint Scanner Affect User Performance?

September 22, 2008
Author(s)
Mary F. Theofanos, Ross J. Micheals, Shahram Orandi, Brian C. Stanton, Nien F. Zhang, Charles L. Sheppard
As the deployment of biometric technologies such as fingerprints has become more widespread in government applications there is an increased awareness of the human-computer interaction that such technologies involve. User behavior can impact operational

IEEE TC-10: Update 2008

September 22, 2008
Author(s)
Nicholas G. Paulter Jr., Thomas E. Linnenbrink, W. B. Boyer, Robert Graham, S. J. Tilden
There is a world-wide need to standardize terms, test methods, and the computation of performance parameters for devices that generate, measure, and analyze waveforms. Users need to be able to unambiguously specify the device performance required for

Focus on Quality, Predicting FRVT 2006 Performance

September 17, 2008
Author(s)
P J. Phillips, J. R. Beveridge, Geof H. Givens, Bruce A. Draper, Yui M. Lui
This paper summarizes a study carried out on data from the Face Recognition Vendor Test 2006 (FRVT 2006). The finding of greatest practical importance is the discovery of a strong connection between a relatively simple measure of image quality and

Humans versus Algorithms: Comparisons from the Face Recognition Vendor 2006

September 17, 2008
Author(s)
P J. Phillips, Alice J. O'Toole, Abhijit Narvekar
We present a synopsis of results comparing the performance of humans with face recognition algorithms tested in the Face Recognition Vendor Test (FRVT) 2006 and Face Recognition Grand Challenge (FRGC). Algorithms and humans matched face identity in images

Laser Doppler vibrometer employing active frequency feedback

September 17, 2008
Author(s)
Akobuije D. Chijioke, John R. Lawall
We present a heterodyne Michelson interferometer for vibration measurement in which feedback is used to obviate the need to unwrap phase data. The Doppler shift of a vibrating target mirror is sensed interferometrically and compensated by means of a

Multi-sample micro-slit rheometry

September 17, 2008
Author(s)
Doyoung Moon, Anthony J. Bur, Kalman D. Migler
We have developed a multi-sample micro-slit rheometer MMR which is capable of measurements over a broad range of temperatures, viscosities and shear rates. The instrument is mechanically simple as the flow is generated by external gas pressure and the

Measurement and Characterization of Dynamics in Machining Chip Segmentation

September 16, 2008
Author(s)
Eric P. Whitenton, Jarred C. Heigel, Robert W. Ivester
Comparing measured chip formation characteristics to those predicted by machining models is an important technique for testing the validity of those models. These characteristics include whether a chip is continuous or segmented, as well as the frequency

Resistivity study of si-doped GaN nanowires grown by catalyst-free MBE

September 16, 2008
Author(s)
Lorelle Mansfield, Paul T. Blanchard, Devin M. Rourke, Aric W. Sanders, Norman A. Sanford, Kristine A. Bertness
GaN nanowires doped with silicon were grown on Si(111) substrates by catalyst-free molecular beam epitaxy (MBE). Contacts were fabricated to single nanowires with a Ti/Al metallization scheme. Low-resistance ohmic contacts were achieved after annealing for

Strategies for hp-Adaptive Refinement

September 16, 2008
Author(s)
William F. Mitchell
In the hp-adaptive version of the finite element method for solving partial differential equations, the grid is adaptively refined in both h, the size of the elements, and p, the degree of the piecewise polynomial approximation over the element. The
Displaying 29651 - 29675 of 74178