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Displaying 22926 - 22950 of 73741

Optimal Diffusion Coefficient Estimation in Single-Particle Tracking

June 21, 2012
Author(s)
Xavier Michalet, Andrew J. Berglund
Recent results provide new theoretical concepts and practical algorithms for diffusion coefficient estimation in single-particle tracking. We compare two recent approaches to estimate the diffusion coefficient from a single-particle trajectory in the

Airspeed Calibration Services: Laser Doppler Anemometer Calibration and Its Uncertainty

June 20, 2012
Author(s)
Iosif I. Shinder, Michael R. Moldover, J. M. Hall, Mike Duncan, Joe Keck
The National Institute of Standards and Technology (NIST) and the Oak Ridge National Laboratory (ORNL) are improving their airspeed calibration services. Both laboratories use spinning disks to generate linear velocities that are traceable to NIST’s length

Experimental and Thermodynamic Assessment of Phase Equilibria in the Co-Mo system

June 20, 2012
Author(s)
Katsunari Oikawa, Ursula R. Kattner, J. Sato, T. Omori, M. Jang, K. Anzai, Kiyohito Ishida
Phase equilibria of the solid phases in the Co-Mo system were investigated using two-phase alloys and the diffusion couple technique. In addition, systematic studies of phase transformations were conducted by differential scanning calorimetry, and

Improved Nozzle Manifold for Gas Flow Calibrations

June 20, 2012
Author(s)
Aaron N. Johnson, Chunhui Li, John D. Wright, Gina M. Kline, Christopher J. Crowley
We developed a new nozzle manifold that reduced the uncertainty of flow calibrations from 0.09 % to as low as 0.074 % for flows of air up to 0.84 kg/s (43 000 L/min at reference conditions of 101.325 kPa and 293.15 K). The nozzle manifold also reduces the

In situ stress measurement during electrodeposition of Ni_(x)Pt_(1-x) alloys

June 20, 2012
Author(s)
Jae W. Shin, Carlos M. Hangarter, Ugo Bertocci, Yihua Y. Liu, Thomas P. Moffat, Gery R. Stafford
Stress generation was examined during the electrodeposition of NixPt1-x alloys from 0.5 M NaCl + 3 mM K2PtCl4 + 0.1 M NiCl2 (pH=2.5), using the wafer curvature method, in films measuring less than 50 nm in thickness. Steady state tensile stress, ranging

Large Stroke Electrostatic Comb-Drive Actuators Based on a Novel Flexure Mechanism

June 20, 2012
Author(s)
Mohammad Olfatnia, Siddharth Sood, Jason J. Gorman, Shorya Awtar
This paper reports in-plane electrostatic comb-drive actuators with stroke as large as 245 µm, achieved by employing a novel Clamped Paired Double Parallelogram (C-DP-DP) flexure mechanism. For a given flexure beam length (L1), comb gap (G), and actuation

Tests of the Extended Lee Model Using Three Different Turbine Meters

June 20, 2012
Author(s)
Jodie G. Pope, John D. Wright, Sherry D. Sheckels
We report additional tests of our “extended Lee model” for calibrating turbine meters. The model accounts for 1) Reynolds number (Re) dependent drag and lift, 2) bearing static drag and 3) bearing viscous drag. Initially, we tested this model using a dual

Tools and Approaches for the Assessment of Nanomaterial Induced Oxidative DNA Damage

June 20, 2012
Author(s)
Elijah J. Petersen, Bryce J. Marquis, Pawel Jaruga, M Miral Dizdar, Bryant C. Nelson
Hyphenated mass spectrometry techniques have been employed as one of the primary analytical tools for investigating the effects of ionizing radiation, chemical/biological carcinogens, and oxygen derived free radicals on the induction and subsequent repair

USARSim/ROS: A Combined Framework for Robotic Control and Simulation

June 20, 2012
Author(s)
Stephen B. Balakirsky, Zeid Kootbally
The Robot Operating System (ROS) has been steadily gaining popularity among robotics researchers as an open source framework for robot control. The Unified System for Automation and Robot Simulation (USARSim) has been used for many years by robotics

Analysis of Thermal-Conductivity Measurement Data from International Comparison of National Laboratories

June 19, 2012
Author(s)
Bruno Hay, Robert R. Zarr, Clark Stacey, Leonel Lira Cortes, Ulf Hammerschmidt, Nikolay Sokolov, J.T. Zhang, Jean Remy Filtz
For the first time under the auspices of the Bureau International des Poids et Mesures (BIPM), seven national metrology institutes (NMIs) participated in an international interlaboratory comparison on thermal-conductivity measurements by the guarded hot

Ancilla assisted calibration of a measuring apparatus

June 19, 2012
Author(s)
Alan L. Migdall, Giorgio Brida, L. Ciavarella, Ivo P. Degiovanni, Marco Genovese, M. G. Mingolla, M. G. A. Paris, Fabrizio Piacentini, Sergey Polyakov
The rapid development of quantum systems has enabled a wide range of novel and innovative technologies, from quantum information processing to quantum etrology and imaging [113], mainly based on optical systems. Precise characterization techniques of

Demonstration of Superluminal Images

June 19, 2012
Author(s)
Ryan T. Glasser, Ulrich Vogl, Paul D. Lett
Optical pulse propagation with group velocities larger than the speed of light in vacuum, c, or negative, have been demonstrated theoretically and experimentally in a variety of systems [1–5]. The anomalous dispersion required for generating “fast” light

Metastable Crystalline AuGe Catalysts Formed During Isothermal Germanium Nanowire Growth

June 19, 2012
Author(s)
Andrew D. Gamalski, Jerry Tersoff, Renu Sharma, Caterina Ducati, Stephan Hofmann
We observe the formation of metastable AuGe phases without quenching, during strictly isothermal nucleation and growth of Ge nanowires, using video-rate lattice-resolved environmental transmission electron microscopy. We explain the unexpected formation of

Predicting Global Failure Regimes in Complex Information Systems

June 19, 2012
Author(s)
Christopher E. Dabrowski, James J. Filliben, Kevin L. Mills
Over the past five years, we investigated methods to characterize global behavior in large distributed systems and applied those methods to predict effects from deploying alternate distributed control algorithms. The methods we used assess global behaviors
Displaying 22926 - 22950 of 73741
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