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 751 - 775 of 1560

Shielding Effectiveness Measurements of Materials in Nested Reverberation Chambers

May 1, 2003
Author(s)
Christopher L. Holloway, David A. Hill, John M. Ladbury, Galen H. Koepke, R. Garzia
In this paper, we present a technique for determining the shielding effectiveness of materials from nested reverberation chamber measurements. The new approach accounts for both aperture and cavity size effects. Various examples are presented to illustrate

The Alternating Direction Implicit (ADI) Formulation of the Finite-Difference Time-Domain (FDTD) Method: Algorithm and Material Dispersion Implementation

May 1, 2003
Author(s)
Shawn W. Staker, Christopher L. Holloway, Alpesh Bhobe, Melinda Piket-May, Tobin A. Driscoll
The ADI-FDTD technique is an unconditionally stable time-domain numerical scheme, allowing the Δ}t time step to be increased beyond the Courant-Friedrichs-Lewy (CFL) limit. Execution time of a simulation is inversely proportional to Δ}t, and as such

Broadband Permittivity and Loss Tangent Measurements Using a Split-Cylinder Resonator

April 24, 2003
Author(s)
Michael D. Janezic, Edward Kuester, James R. Baker-Jarvis
We summarize a theoretical model for the split-cylinder resonator, based on the mode-matching method, for performing nondestructive permittivity and loss tangent measurements with the split-cylinder resonator. This new model properly takes into account the

Governmental Approaches to Standards in World Trade

April 9, 2003
Author(s)
Roger Marks
Standards have become a critical element in world trade. Within the guidelines set by the World Trade Organization, governments have developed strategies to optimize their benefits with the world standardization system.

Complex Permittivity Measurements of Common Plastics over Variable Temperatures

March 1, 2003
Author(s)
Billy F. Riddle, James R. Baker-Jarvis, Jerzy Krupka
In this paper we present complex permittivity data at macorwave frequencies for many common plastics from 125 K to 375 K. The measurements were made using a TE 01δ dielectric resonator placed inside an environmental chamber. Data are presented for the

Estimation of Q-factors and Resonant Factors

March 1, 2003
Author(s)
Kevin Coakley, Jolene Splett, Michael D. Janezic, Raian K. Kaiser
We estimate the quality factor Q and resonant frequency f 0 of a microwave cavity based on resonance curve observations on an equally-spaced frequency grid. The observed resonance curve is the squared magnitude of an observed complex scattering parameter

Magnetic Thin Film Interlaboratory Comparison

March 1, 2003
Author(s)
Fabio C. da Silva, David P. Pappas, C. M. Wang
A potential low magnetic moment standard reference material (SRM) was studied in an interlaboratory comparison. The mean and the standard deviation of the saturation moment m s, the remanent moment m r, and the intrinsic coercivity H c of nine samples were

Research on Site Qualifications above 1 GHz

February 18, 2003
Author(s)
Michael Windler, Dennis G. Camell
This is a summary of recent efforts conducted under the auspices of the American National Standards Institute (ANSI) Accredited Standards Committee C63, Sub-committee 1, working group 1-13.2. The main purpose of this group is to assess the applicability of

Formation of aluminum oxide thin films on FeAl(110) studied by STM

February 6, 2003
Author(s)
Orhan Kizilkaya, Dustin Hite, David M. Zehner, Phillip T. Sprunger
The surface morphology and atomic structure of clean and oxidized FeAl(l 10) surfaces have been investigated with scanning tunneling microscopy (STM). An incommensurate reconstructed structure, having FeAl2 stoichiometry confined to the outmost layer, is

Calibrated Waveform Measurement with High-Impedance Probes

February 1, 2003
Author(s)
Pavel Kabos, Howard C. Reader, Uwe Arz, Dylan Williams
We develop an on-wafer waveform calibration technique that combines frequency-domain mismatch corrections to account for the effects of the probe on the measurement with an oscilloscope calibration. The mismatch correction is general and can be applied to

A Two-Phase Airframe Shielding Performance Study Using Ultra-wideband Measurement Systems

January 1, 2003
Author(s)
Chriss A. Grosvenor, Robert T. Johnk, David R. Novotny, Seturnino Canales, Claude Weil, Jason Veneman
The National Institute of Standards and Technology participated in a comprehensive study of electromagnetic aircraft shielding. The effort consisted of two parts: (1) shielding measurements on a box model with a simple and precisely controlled geometry

Consideration of possible mass and velocity corrections to magnetic experiments

January 1, 2003
Author(s)
Z. Y. Liu, P. A. Dowben, A P. Popov, David P. Pappas
Gadolinium occurs, in natural abundance, as several isotopes. The possible combinations of different gadolinium isotopes dictates that even for a fixed number of atoms in the cluster, clusters of gadolinium atoms will exhibit a range of masses. This and

Effect of transverse compressive stress on transport critical current density of Y-Ba-Cu-O coated Ni and Ni-W RABiTS tapes

January 1, 2003
Author(s)
Najib Cheggour, John (Jack) W. Ekin, Cameron C. Clickner, Ron Feenstra, P Goyal, D F. Paranthaman, Noel Rutter
Transport properties of yttrium-barium-copper-oxide (YBCO) coatings on both pure-nickel and nickel-3at%tungsten rolling-assisted-biaxially-textured substrates (RABiTS) were tested under transverse compressive stress up to 180 MPa. Transport critical

High-speed switching and rotational dynamics in small magnetic thin-film devices

January 1, 2003
Author(s)
Stephen E. Russek, Shehzaad F. Kaka, Robert McMichael, Michael J. Donahue
The intent of this chapter is to review high frequency magnetic device measurements and modeling work at NIST which is being conducted to support the development of high-speed read sensors, magnetic random access memory, and magnetoelectronic applications

Magnetic Technology Division: Programs, Activities, and Accomplishments

January 1, 2003
Author(s)
Ronald B. Goldfarb
The Magnetic Technology Division develops and disseminates measurement technology for industries broadly concerned with magnetic information storage and superconductor power. The division is located in Boulder, Colorado, part of the Electronics and

Micromechanical Instruments for Ferromagnetic Measurements

January 1, 2003
Author(s)
John M. Moreland
I review some of the novel methods for measuring ferromagnetic properties of thin films based on micromechanical magnetometers. Measurements rely on the detection of mechanical forces or torques on samples deposited onto microcantilevers. Displacements of

Permittivity Characterization of Low-k Thin films from Transmission-Line Measurements

January 1, 2003
Author(s)
Michael D. Janezic, Dylan Williams, V. Blaschke, A. Karamcheti, Fengbo Hang
We develop a broadband technique for measuring the permittivity of low-k thin films using microstrip transmission-line measurements. From measurements of the complex microstrip propagation constant and the characteristics impedance, we determine the

Radio-Frequency Technology Division: Programs, Activities, and Accomplishments

January 1, 2003
Author(s)
Robert M. Judish, Dennis S. Friday
This publication describes the programs in the Radio-Frequency Technology Division, of the National Institute of Standards and technology. The Radio-Frequency Technology Division is a critical national resource for a wide range of customers. U. S. industry

Reactive epitaxy of beryllium on Si(1 1 1)-(7 x 7)

January 1, 2003
Author(s)
Dustin Hite, Shu-Jung Tang, Phillip T. Sprunger
Scanning tunneling microscopy (STM) and photoelectron spectroscopy (PES) have been used to investigate the nucleation, growth, and structure of beryllium on Si(1 1 1)-(7 x 7). STM indicates that a chemical reaction occurs at temperatures as low as 120 K

Ultrawideband Time- and Frequency-Domain Characterization of EMC Facilities

January 1, 2003
Author(s)
David R. Novotny, Robert T. Johnk, Claude Weil, Seturnino Canales
We have developed a methodology to determine the quality of an EMC test facility using equipment generally available to RF testing services. By utilizing both the time- and frequency-domain, an accurate picture of the scattering and modal properties of the
Displaying 751 - 775 of 1560