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NIST Authors in Bold

Displaying 23301 - 23325 of 73741

Technical Note on Unexpected Bias in NIST 4p Ionization Chamber Measurements

April 4, 2012
Author(s)
Michael P. Unterweger, Ryan P. Fitzgerald
The NIST 4π pressurized ionization chamber “A” (PIC “A”) has been the mainstay for secondary calibrations of liquid and gaseous gamma-ray emitting sources for the last 40-45 years. It has also been the main instrument used to measure the half-lives of

IREX III - Performance of Iris Identification Algorithms

April 3, 2012
Author(s)
Patrick J. Grother, George W. Quinn, James R. Matey, Mei L. Ngan, Wayne J. Salamon, Gregory P. Fiumara, Craig I. Watson
Iris recognition has long been held as an accurate and fast biometric. In the first public evaluation of one-to-many iris identification technologies, this third activity in the Iris Exchange (IREX) program has measured the core algorithmic efficacy and

Performance of Steel Moment Connections under a Column Removal Scenario. I: Experiments

April 3, 2012
Author(s)
Hai S. Lew, Joseph A. Main, Stephen D. Robert, Fahim Sadek, Vincent Chiarito
This paper presents an experimental study of two full-scale steel beam-column assemblies, each comprising three columns and two beams, to (1) define their response characteristics under a column removal scenario, including the capacity of the beams and

Performance of Steel Moment Connections under a Column Removal Scenario. II: Analysis

April 3, 2012
Author(s)
Fahim H. Sadek, Joseph Main, Hai S. Lew, Sherif El-Tawil
This paper presents a computational investigation of the response of steel beam-column assemblies with moment connections under monotonic loading conditions simulating a column removal scenario. Two beam-column assemblies are analyzed, which incorporate (1

Basing Cybersecurity Training on User Perceptions

April 2, 2012
Author(s)
Susanne M. Furman, Mary F. Theofanos, Yee-Yin Choong, Brian C. Stanton
The National Initiative for Cybersecurity Education (NICE) will be conducting a nationwide awareness and outreach program to effect behavioral change. To be effective, an educational campaign must first understand users’ perceptions of computer and online

Dielectrophoretic Cell Capture on Polyester Membranes

April 2, 2012
Author(s)
Conni Hanke, Petra S. Dittrich, Darwin Reyes-Hernandez
A new system for dielectrophoretic cell capture on porous polyester (PET) membranes is presented. Conventional photolithographic techniques were used to fabricate gold microelectrodes on a PET membrane. We characterized these electrodes to proof that there

Paramagnetic Spin Correlations in Colossal Magnetoresistive La 0.7 Ca 0.3 MnO 3

April 2, 2012
Author(s)
Joel Helton, Matthew B. Stone, Dmitry A. Shulyatev, Yakov M. Mukovskii, Jeffrey W. Lynn
Neutron spectroscopy measurements reveal dynamic spin correlations throughout the Brillouin zone in the colossal magnetoresistive system La 0.7Ca 0.3MnO 3 at 265 K ({approx}1.03T c). The long-wavelength behavior is consistent with spin diffusion, yet an

Workflow and Electronic Health Records in Small Medical Practices

April 2, 2012
Author(s)
Mala Ramaiah, Eswaran Subrahmanian, Ram D. Sriram, Bettijoyce B. Lide
This paper analyzes the workflow and implementation of electronic health record (EHR) systems across different functions in small physician offices. We characterize the differences in the offices based on the levels of computerization in terms of workflow

Mechanisms of free radical-induced damage to DNA

April 1, 2012
Author(s)
M Miral Dizdar, Pawel Jaruga
Endogenous and exogenous sources cause free radical-induced DNA damage in living organisms by a variety of mechanisms. The highly reactive hydroxyl radical reacts with the heterocyclic DNA bases and the sugar moiety near or at diffusion-controlled rates by

Neutron Studies of Tb 2 Mo 2 O 7

April 1, 2012
Author(s)
Jason S. Gardner, G. Ehlers, S. O. Diallo
We have used the new high energy resolution spectrometer (BaSis), at the Spallation Neutron Source in Oak Ridge, to conclusively prove the existence of a low energy mode at 0.34(1) meV in the spin glass Tb 2mo 2O 7. This mode is reminiscent of the

Optical fiber-coupled cryogenic radiometer with carbon nanotube absorber

April 1, 2012
Author(s)
David J. Livigni, Nathan A. Tomlin, Christopher L. Cromer, John H. Lehman
A cryogenic radiometer was constructed for direct-substitution optical fiber power measurements. The cavity is intended to operate at the 3 K temperature stage of a dilution refrigerator or 4.2 K stage of a liquid cryostat. The optical fiber is removable

The Evolution of Time Measurement Part V: Radio Controlled Clocks

April 1, 2012
Author(s)
Michael A. Lombardi
A historical article about the origins and the development of radio controlled clocks (Part IV of a IV-part series). It describes the first time signal radio stations, the early use of telegraphic time codes, and the modern use of digital time codes. It
Displaying 23301 - 23325 of 73741
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