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Displaying 29601 - 29625 of 74115

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

Assessing Face Acquisition

September 15, 2008
Author(s)
Mary F. Theofanos, Brian C. Stanton, Charles L. Sheppard, Ross J. Micheals, John M. Libert, Shahram Orandi
The requirements necessary for taking a successful face picture are arguably the least constrained of any biometric. The camera must be operational, and the subject must be illuminated sufficiently and facing the camera. Yet, a significant portion of the

Building Air Change Rate Estimates for CBR Analysis

September 15, 2008
Author(s)
Andrew K. Persily
Building air change rates impact energy consumption for space conditioning and indoor contaminant levels in relation to general indoor air quality issues as well as occupant exposure to airborne chemical, biological and radiological (CBR) agents. With

Detector-based calibration procedures for tristimulus colorimeter standards

September 15, 2008
Author(s)
George P. Eppeldauer, Carl C. Miller, Yoshihiro Ohno
Two reference and three working standard tristimulus colorimeters have been developed at the National Institute of Standards and Technology (NIST) to utilize the recently introduced detector based colorimeter calibration method [1]. The tristimulus

Multi-level effects in the Rabi oscillations of a Josephson phase qubit

September 15, 2008
Author(s)
S. K. Dutta, H. Paik, T. A. Palomaki, J. R. Anderson, A. J. Dragt, C. J. Lobb, F. C. Wellstood, Frederick Strauch, Kaushik Mitra, Eite Tiesinga
We present Rabi oscillation measurements of an Nb/AlOx/Nb dc SQUID phase qubit with a 100 ¿m2 area junction acquired at 25 mK over a range of microwave power and frequency detuning. Given the slightly anharmonic level structure of the qubit, several

Performance Evaluation of Laser Trackers

September 15, 2008
Author(s)
Balasubramanian Muralikrishnan, Daniel S. Sawyer, Christopher J. Blackburn, Steven D. Phillips, Bruce R. Borchardt, William T. Estler
The American Society for Mechanical Engineers (ASME) recently released the ASME B89.4.19 Standard [1] on performance evaluation of spherical coordinate instruments such as laser trackers. At the National Institute of Standards and Technology (NIST), we can

QOS-Aware Channel Scanning for IEEE 802.11 Wireless LAN

September 15, 2008
Author(s)
Nada T. Golmie, Sang-Jo Yoo
Channel scanning is an important aspect of seamless handovers since it is required in order to find a target point of attachment (PoA). In the IEEE 802.11 WLAN, scanning of other channels causes service disruptions with the current AP so that the provided

Relative Intensity Noise Suppression for Photonic Links

September 15, 2008
Author(s)
Craig Nelson, Archita Hati, David A. Howe
We propose and experimentally demonstrate a novel technique to reduce laser relative intensity noise (RIN). A RIN suppression servo is usually implemented by inserting an intensity modulator in the optical path and controlling measured light intensity with

Effect of Annealing on Transport Properties of MgO-based Magnetic Tunnel Junctions

September 12, 2008
Author(s)
Ann Chiaramonti Debay, Daniel Schreiber, William F. Egelhoff Jr., D. N. Seidman, Amanda K. Petford-Long
The effect of annealing on the transport behavior of CoFe/MgO/CoFe magnetic tunnel junctions has been studied using a combination of site-specific in-situ transmission electron microscopy and three-dimensional atom probe tomography. Annealing at 340 °C for
Displaying 29601 - 29625 of 74115