U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 29651 - 29675 of 74061

Fast, bias-free algorithm for tracking single particles with variable size and shape

August 26, 2008
Author(s)
Andrew J. Berglund, Matthew D. McMahon, Jabez J. McClelland, James A. Liddle
We introduce a fast and robust technique for single-particle tracking with nanometer accuracy.We extract the center-of-mass of the image of a single particle with a simple, iterative algorithm that efficiently suppresses background-induced bias in a

Molecule induced interface states dominate charge transport in Si-alkyl-metal junctions

August 26, 2008
Author(s)
Lam H. Yu, Nadine E. Gergel-Hackett, Christopher D. Zangmeister, Christina A. Hacker, Curt A. Richter, James G. Kushmerick
Abstract. Semiconductor-molecule-metal junctions consisting of alkanethiol mono- layers self-assembled on both p+ and n¡ type highly doped Si(111)wires contacted with a 10 ¹m Au wire in a crossed-wire geometry are examined. Low temperature transport

Neutron-scattering study of the oxypnictide superconductor LaFeAsO 0.87 F 0.13

August 26, 2008
Author(s)
Yiming Qiu, M. Kofu, Wei Bao, S.-H. Lee, Qingzhen Huang, Taner N. Yildirim, John R. Copley, Jeffrey Lynn, T. Wu, G. Wu, X. H. Chen
The recently discovered superconductor LaO0.87F0.13FeAs (TC≈26 K) was investigated using the neutron-scattering technique. No spin-density-wave (SDW) order was observed in the normal state or in the superconducting state, both with and without an applied

NIST Microform Calibration System for Rockwell Hardness Standardization

August 25, 2008
Author(s)
Jun-Feng Song, Samuel R. Low III, Xiaoyu A. Zheng
In the uncertainty budget of Rockwell hardness tests, microform geometric errors of the diamond indenter are a major contributor. The microform calibration of Rockwell diamond indenters has been one of the key steps for Rockwell hardness standardization

Ratio of the Al + and Hg + Optical Clock Frequencies to 17 Decimal Places

August 25, 2008
Author(s)
Wayne M. Itano, Till P. Rosenband, David Hume, P.O. Schmidt, Chin-Wen Chou, A. Brusch, Luca Lorini, Windell Oskay, Robert E. Drullinger, Sarah Bickman, Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, William C. Swann, Nathan R. Newbury, David J. Wineland, James C. Bergquist
Frequency standards (atomic clocks) based on narrow optical transitions in 27Al + and 199Hg + have been developed over the past several years at NIST. These two types of standards are both based on single ions confined in Paul traps, but differ in the

Style Guide for Voting System Documentation

August 25, 2008
Author(s)
Dana E. Chisnell, Susan C. Becker, Sharon J. Laskowski, Svetlana Z. Lowry
The goal of this style guide is to provide specific guidance to improve the usability of documentation used by poll workers and election support staff. The Voting System Documentation Style Guide incorporates best practices for writing documentation as it

3D Reconstruction of Rough Terrain for USARSim Using a Height-map Method

August 21, 2008
Author(s)
Gael Roberts, Stephen B. Balakirsky, Sebti Foufou
In this paper, we present a process for a simplified reconstruction of rough terrains from point clouds acquired using laser scanners. The main idea of this work is to build height-maps which are level gray-scale images representing the ground elevation

Characterization of Laminin on Silanized Polydimethylsiloxane

August 21, 2008
Author(s)
Joy P. Dunkers, Lisa M. Hughes, Hae-Jeong Lee, Marvi Matos, Marcus T. Cicerone
In this work, we characterize a protein surface on a flexible polydimethylsiloxane substrate (PDMS) capable of undergoing strain. We compare the results from two different surface treatments: physically adsorbed laminin on PDMS and laminin deposited on

Characterization of Monolayer Formation on Aluminum-Doped Zinc Oxide Thin Films

August 21, 2008
Author(s)
C Rhodes, S E. Lappi, Daniel A. Fischer, S Sambasivan, Jan Genzer, S Franzen
The optical and electronic properties of aluminum-doped zinc oxide (AZO) thin films on a glass substrate have been investigated experimentally and theoretically. Optical studies with coupling in the Kretschmann configuration reveal an angle-dependent

Dynamic 6DOF Metrology for Evaluating a Visual Servoing

August 21, 2008
Author(s)
Tommy Chang, Tsai H. Hong, Michael O. Shneier, G Holguin, J Park, Roger D. Eastman
In this paper we demonstrate the use of a dynamic, six-degree-of-freedom (6DOF) laser tracker to empirically evaluate the performance of a real-time visual servoing implementation, with the objective of establishing a general method for evaluating real

Fuzzy-Logic-Based Approach for Identifying Objects of Interest in the PRIDE Framework

August 21, 2008
Author(s)
Zeid Kootbally, Craig I. Schlenoff, Rajmohan Madhavan, Sebti Foufou
On-road autonomous navigation of autonomous vehicles requires real--time motion planning in the presence of moving objects. Based on sensed data of moving objects in the environment and the situation it finds itself in, an autonomous vehicle has to plan a

HLPR Chair A Novel Patient Transfer Device

August 21, 2008
Author(s)
Roger V. Bostelman, James S. Albus
In this paper, we briefly describe the design of the Home Lift, Position and Rehabilitation (HLPR) Chair, invented at the National Institute of Standards and Technology (NIST), Manufacturing Engineering Laboratory (MEL) under the Healthcare Mobility

Magnetic order of the iron spins in NdFeAsO

August 21, 2008
Author(s)
Ying Chen, Jeffrey Lynn, Jiying Li, G. J. Li, G. F. Chen, J. L. Luo, N. L. Wang, Pengcheng Dai, Clarnia dela Cruz, H. A. Mook
Polarized and unpolarized neutron diffraction measurements have been carried out to investigate the iron magnetic order in undoped NdOFeAs. Antiferromagnetic order is observed below 141(6) K, which is in close proximity to the structural distortion

Magneto-Optical-Trap-Based, High Brightness Ion Source for Use as a Nanoscale Probe

August 21, 2008
Author(s)
James L. Hanssen, Shannon B. Hill, Jon Orloff, Jabez J. McClelland
We report on the demonstration of a low emittance, high brightness ion source based on magneto-optically trapped neutral atoms. Our source has ion optical properties comparable to or better than those of the commonly used liquid metal ion source. In

Ontological Perspectives for Autonomy Performance

August 21, 2008
Author(s)
Hui-Min Huang, Elena R. Messina, Tsai Hong Hong, Craig I. Schlenoff
Goals must be assigned for any unmanned system’s (UMS) operation before the system’s autonomous performance can be measured. In this paper, we began to construct an ontology for mission goals that could serve as a template for stating the goal. We apply

Performance of Super-Resolution Enhancement for Flash LADAR Data

August 21, 2008
Author(s)
Tsai Hong Hong, Shuowen Hu, S. S. Young
Flash laser detection and ranging (LADAR) systems are increasingly used in robotics applications for autonomous navigation and obstacle avoidance. Their compact size, high frame rate, wide field of view, and low cost are key advantages over traditional

Ultra-low-noise all-fiber photon pair source

August 21, 2008
Author(s)
Shellee D. Dyer, Martin J. Stevens, Burm Baek, Sae Woo Nam
We demonstrate an all-fiber photon pair source with the highest coincidence-to-accidental ratio (CAR) reported to date in the fiber optic telecom C-band.

Measurement science for climate remote sensing

August 20, 2008
Author(s)
Gerald T. Fraser, Steven W. Brown, Raju V. Datla, Bettye C. Johnson, Keith R. Lykke, Joseph P. Rice
The Earth s climate is very complex and highly variable, making it difficult to measure and model small changes that occur over decadal and longer time scales. The resulting uncertainties in measurement and modeling underlie the longterm debate over the

Thermodynamic Property Values for Enzyme-catalyzed Reactions

August 20, 2008
Author(s)
Robert N. Goldberg
This chapter deals with how one can obtain values of thermodynamic properties specifically the apparent equilibrium constant K, the standard molar transformed Gibbs energy change rG, and the standard molar transformed enthalpy change rH for
Displaying 29651 - 29675 of 74061