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Search Publications

NIST Authors in Bold

Displaying 31076 - 31100 of 73830

The SIM Network: Improved Time Coordination for North, Central, and South America

April 23, 2008
Author(s)
Jose M. Lopez, Michael A. Lombardi, Andrew Novick, Jean-Simon Boulanger, R. de Carvalho, R. Solis, Francisco Jimenez
The Sistema Interamericano de Metrologia (SIM) consists of national metrology institutes (NMIs) located in the 34 member nations of the Organization of American States (OAS), which extends throughout North, Central, and South America, and the Caribbean

Fast-responding nonlinear phase shifter using a signal-wave gain medium

April 22, 2008
Author(s)
Lu Deng, Edward W. Hagley, Kaijun Jiang, Marvin G. Payne
Using a full density matrix formalism we show that for a lifetime broadened four-level scheme with a signal wave gain medium a large nonlinear phase shift can be induced without signal wave slowdown and attenuation. In this system the signal wave acquires

Fundamental Constants and Tests of Theory in Rydberg States of Hydrogen-like Ions

April 22, 2008
Author(s)
Ulrich D. Jentschura, Peter Mohr, Joseph N. Tan, B. J. Wundt
A comparison of precision frequency measurements to quantum electrodynamics (QED) predictions for Rydberg states of hydrogen-like ions can yield information on values of fundamental constants and test theory. With the results of a calculation of a key QED

Microstructure of oligofluorene asymmetric derivatives in organic thin film transistors

April 22, 2008
Author(s)
Quan Yuan, Stefan C. Mannsfeld, Ming L. Tang, Mark Roberts, Michael F. Toney, Dean DeLongchamp, Zhenan Bao
In organic thin film transistors (OTFT), modifying the molecular chemical structure affects the molecular packing and thin film morphology, which both sensitively influence the charge carrier mobility. A detailed understanding of the interplay of molecular

High resolution X-ray transition-edge sensor cooled by tunnel junction refrigerators and operated above the transition temperature

April 21, 2008
Author(s)
Nathan A. Tomlin, Galen C. O\'Neil, James A. Beall, Gene C. Hilton, Kent D. Irwin, Daniel R. Schmidt, Leila R. Vale, Joel N. Ullom
We demonstrate cooling of an X-ray transition-edge sensor (TES) using solid-state refrigerators based on normal-metal / insulator / superconductor (NIS) tunnel junctions. We are able to operate the TES at a bath temperature of 260 mK, which is 75 mK above

Infrastructure System Design Methodology for Smart ID Cards Deployment

April 19, 2008
Author(s)
Ramaswamy Chandramouli
With the increasing use of smart cards for identity verification of individuals, it has become imperative for organizations to properly design and engineer the expensive infrastructure system that supports smart card deployment. Apart from sound system

Atoms in a Radio-Frequency-Dressed Optical Lattice

April 18, 2008
Author(s)
Ian B. Spielman, James V. Porto, William D. Phillips, Ben Brown, Patricia Lee, Nathan Lundblad
We load cold atoms into an optical lattice dramatically reshaped by radio-frequency coupling of statedependent lattice potentials. This radio-frequency dressing changes the unit cell of the lattice at a subwavelength scale, such that its curvature and

Interference Avoidance in Rapidly Deployed Wireless Ad hoc Incident Area Networks

April 18, 2008
Author(s)
Mohamed T. Refaei, Nader Moayeri, Michael R. Souryal
A common strategy for responding to indoor emergency scenarios is to rapidly deploy a group of first responders inside the incident area and an incident command center outside of the incident area. First responders are equipped with radios that allow them

Origin of Adhesion in Humid Air

April 18, 2008
Author(s)
Doo-In Kim, Jaroslaw Grobelny, Pradeep N. Namboodiri, Robert F. Cook
The origin of adhesion at nanoscale contacts in humid air is investigated by pull-off force measurements using atomic force microscopes in controlled environments from ultra-high vacuum through various humidity conditions to water. An equivalent work of

Crystal Structure, Stoichiometry, and Dielectric Relaxation in Bi 3.32 Nb 7.09 O 22.7 and Structurally Related Ternary Phases

April 17, 2008
Author(s)
I E. Grey, Terrell A. Vanderah, W G. Mumme, Robert S. Roth, Jorge T. Guzman, Juan C. Nino, Igor Levin
Ceramic materials which exhibit high relative dielectric permittivities and are processible at temperatures in the 1000 C to 1200 C range are of interest for embedded elements such as capacitor, resonators, and filters. Complex titanates, niobates, and

On Maximizing Provider Revenue in Market-based Compute Grids

April 17, 2008
Author(s)
Vladimir V. Marbukh, Kevin L. Mills
Market-based compute grids encompass service providers offering limited resources to potential users with varying demands and willingness to pay. Providers face difficult decisions about which jobs to admit and when to schedule admitted jobs. For this

PIE: An Online Prediction System for Protein-Protein Interactions from Text

April 17, 2008
Author(s)
Sun Kim, Soo-Yong Shin, In-Hee Lee, Soo-Jin Kim, Ram D. Sriram, Byoung-Tak Zhang
bio-text mining area, since the PPI information is critical for understanding biological processes. However, there are very few open systems available on the Web and most of the systems focus on keyword searching based on prede¯ned PPIs. PIE (Protein

Second Preimage Attacks on Dithered Hash Functions

April 17, 2008
Author(s)
Elena Andreeva, Charles Bouillaguet, Pierre-Alain Fouque, Jonathan J. Hoch, John M. Kelsey, Adi Shamir, Sebastien Zimmer
We develop a new generic long-message second preimage attack, based on combining the techniques in the second preimage attacks of Dean Dean99} and Kelsey and Schneier KS05} with the herding attack of Kelsey and Kohno KK06}. We show that these generic

Shear Thinning Near the Critical Point of Xenon

April 17, 2008
Author(s)
Robert F. Berg, Michael R. Moldover, M Yao, G A. Zimmerli
We measured shear thinning, a viscosity decrease ordinarily associated with complex liquids, near the critical point of xenon. The data span the range of reduced shear rates: 0.001 < γτ < 700, where γτ is the shear rate scaled by the relaxation time τ of

Physical characterization methods for iron-oxide contrast agents encapsulated within a targeted liposome-based delivery system

April 16, 2008
Author(s)
John A. Dagata, Natalia Farkas, Cindi L. Dennis, Robert D. Shull, Vincent A. Hackley, Charles W. Yang, Kathleen F. Pirollo, Esther H. Chang
Intact liposome-based targeted nanoparticle delivery systems (NDS) are immobilized by nonselective binding and characterized by scanning probe microscopy (SPM) in a fluid imaging environment. The size, size distribution, functionality, and stability of an

An Evaluation of Description Logic for the Development of Product Models

April 15, 2008
Author(s)
Xenia Fiorentini, Sudarsan Rachuri, Mahesh Mani, Steven J. Fenves, Ram D. Sriram
The languages and logical formalisms developed by information scientists and logicians concentrate on the theory of languages and logical theorem proving. These languages, when used by domain experts to represent their domain of discourse, most often have
Displaying 31076 - 31100 of 73830
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