Criteria for the Installation of Energy Conservation Measures (open access)

Criteria for the Installation of Energy Conservation Measures

From abstract: Standard installation practices were developed to assist in assuring the effectiveness and safety of energy conservation measures installed under the Residential Conservation Service (RCS). They serve as mandatory standards under RCS but are recommended guides for all installations of the covered materials and products. The criteria are being used by DoE to develop training manuals for installers, inspectors, and energy auditors.
Date: July 1981
Creator: Trechsel, Heinz R. & Launey, Shelia J.
Object Type: Report
System: The UNT Digital Library
Interactive FORTRAN Programs for Micro Computers to Calculate the Thermophysical Properties of Twelve Fluids (MIPROPS) (open access)

Interactive FORTRAN Programs for Micro Computers to Calculate the Thermophysical Properties of Twelve Fluids (MIPROPS)

From abstract: The thermophysical and transport properties of selected fluids have been programmed in FORTRAN 77 which is available for micro computers. The input variables are any two of P, p, T (pressure, density, and temperature) in the single phase regions, and either P or T for the saturated liquid or vapor states. The output is pressure, density, temperature, internal energy, enthalpy, entropy, specific heat capacities (Cp and Cv), speed of sound and, in most cases, viscosity, thermal conductivity and dielectric constant.
Date: May 1986
Creator: McCarty, Robert D.
Object Type: Report
System: The UNT Digital Library
Design and Error Analysis for the WR10 Thermal Noise Standard (open access)

Design and Error Analysis for the WR10 Thermal Noise Standard

From introduction: This note describes the design and error analysis of a WR10 thermal noise power standard. The standard is designed to operate at the boiling point of liquid nitrogen with a noise temperature accurate to plus or minus 1 K.
Date: December 1983
Creator: Daywitt, William C.
Object Type: Report
System: The UNT Digital Library
Theory of Near-Field Phased Arrays for Electromagnetic Susceptibility Testing (open access)

Theory of Near-Field Phased Arrays for Electromagnetic Susceptibility Testing

From introduction: The feasibility of using a near-field array for electromagnetic susceptibility testing is studied. The basic objective is to control the element weightings such that a plane wave is generated within the test volume. The basic theory is developed for arbitrary array geometries, and numerical results are obtained for finite planar arrays. A general near-field array synthesis technique is developed, and the technique minimizes the mean square error in the test volume while constraining the array excitations. The constraint prevents large excitations and is useful in minimizing the fields outside the test volume. The basic idea looks promising, but some practical considerations, such as bandwidth and angular scanning limitations, require further theoretical and experimental investigation.
Date: February 1984
Creator: Hill, D. A.
Object Type: Report
System: The UNT Digital Library
Electromagnetic-Acoustic-Transducer/Synthetic-Aperture System for Thick-Weld Inspection (open access)

Electromagnetic-Acoustic-Transducer/Synthetic-Aperture System for Thick-Weld Inspection

Abstract: This report describes a system based on electromagnetic-acoustic transducers (EMATs) as an approach to automated nondestructive evaluation of thick weldments (>25 mm). Good signal-to-noise ratios, often a problem with EMATs, were possibTe through careful design of the transducers and associated electronic circuits and the use of signal averaging. At 454 kHz, the transducers produce shear-horizontal waves of approximately 7-mm wavelength in steel. The long wavelength permits determination of through-thickness flaw depth from the amplitudes of scattered ultrasonic waves. A minicomputer controlled transducer positioning and acquired the digitized ultrasonic waveforms for synthetic aperture processing. The synthetic aperture technique further improved signal quality and yielded flaw localization through the weld thickness. Measurements on artificial flaws demonstrated a detectability threshold of 0.5 mm (through thickness) and sizing ability up to 2.5 mm, in agreement with theoretical predictions. Details include the design of the transducers and electronics, as well as the mechanical positioner, signal processing algorithms, and complete computer program listing.
Date: 1984
Creator: Fortunko, C. M.; Schramm, R. E.; Moulder, J. C. & McColskey, J. D.
Object Type: Report
System: The UNT Digital Library
Small Aperture Analysis of the Dual TEM Cell and an Investigation of Test Object Scattering in a Single TEM Cell (open access)

Small Aperture Analysis of the Dual TEM Cell and an Investigation of Test Object Scattering in a Single TEM Cell

Introduction: Small aperture theory is used to investigate the dual TEM cell. Analyzing coupling through an empty versus a loaded aperture leads to a model of dual TEM cell shielding effectiveness measurements. Small obstacle scattering yields results for both the field perturbation and the change in a cell's transmission line characteristics due to the presence of a test object in a TEM cell. In each case, theoretical values are compared to experimental data.
Date: 1984
Creator: Wilson, Perry F. & Ma, Mark T.
Object Type: Report
System: The UNT Digital Library
Transparent Metrology of Signal to Noise Ratios of Noisy Band-Limited Digital Signals (open access)

Transparent Metrology of Signal to Noise Ratios of Noisy Band-Limited Digital Signals

From abstract: I propose the use of a template method for quantitative, correct, and transparent measurement of signal power to additive noise power ratios (SNR) of digital signals and systems under full operating conditions. Outer guard chips of digital templates hold intersymbol interference fixed on inner target chips in realizations of the respective template patterns in traffic. The proposed template method needs to be developed and proven as a potentially valuable metrology capability; it can be especially important for real time online performance assessment and monitoring of digital communication systems.
Date: June 1985
Creator: Halford, Donald
Object Type: Report
System: The UNT Digital Library
Automated Measurement of Frequency Response of Frequency-Modulated Generators Using the Bessel Null Method (open access)

Automated Measurement of Frequency Response of Frequency-Modulated Generators Using the Bessel Null Method

From abstract: This paper describes a Bessel null technique to measure the frequency response of a frequency-modulated rf carrier and a program to automate frequency response measurements of signal generators with output frequencies from 0.450 to 2000 MHz. The measurements obtained using this technique are more precise than those obtained by a highly trained technician using a manual system.
Date: March 1986
Creator: Major, J. R.; Livingston, E. M. & Adair, Robert T.
Object Type: Report
System: The UNT Digital Library
A Statistical Characterization of Electroexplosive Devices Relevant to Electromagnetic Compatibility Assessment (open access)

A Statistical Characterization of Electroexplosive Devices Relevant to Electromagnetic Compatibility Assessment

Abstract: Electroexplosive devices (EEDs) are electrically fired explosive initiators used in a wide variety of applications. The nature of most of these applications requires that the devices function with near certainty when required and remain inactive otherwise. Recent concern with pulsed electromagnetic interference (EMI) and nuclear electromagnetic pulse (EMP) made apparent the lack of methodology for assessing EED vulnerability. A new and rigorous approach for characterizing EED firing levels is developed in the context of statistical linear models and is demonstrated in this paper. We combine statistical theory and methodology with thermodynamic modeling to determine the probability that an EED, of a particular type, fires when excited by a pulse of a given width and amplitude. The results can be applied to any type of EED for which the hot-wire explosive binder does not melt below the firing temperature. Included are methods.for assessing model validity and for obtaining probability plots, called "Firing Likelihood Plots". A method of measuring the thermal time constant of an EED is given. This parameter is necessary to evaluate the effect of a train of pulses. These statistical methods are both more general and more efficient than previous methods for EED assessment. The results provide information …
Date: May 1986
Creator: Friday, Dennis S. & Adams, John W.
Object Type: Report
System: The UNT Digital Library
A Study of Techniques for Measuring the Electromagnetic Shielding Effectiveness of Materials (open access)

A Study of Techniques for Measuring the Electromagnetic Shielding Effectiveness of Materials

Abstract: Shielding effectiveness relates to a material's ability to reduce the transmission of propagating fields in order to electromagnetically isolate one region from another. Because a complex material's shielding capability is difficult to predict, it often must be measured. A number of measurement approaches are studied including the use of a shielded room, coaxial transmission line holders, time domain signals, the dual TEM cell, and an apertured TEM cell in a reverberation chamber. In each case, we consider the system's frequency range, test sample requirements, test field type, dynamic range, time required, analytical background, and present data taken on a common set of materials.
Date: May 1986
Creator: Wilson, Perry F. & Ma, Mark T.
Object Type: Report
System: The UNT Digital Library
Fitness-for-Service Criteria for Assessing the Significance of Fatigue Cracks in Offshore Structure (open access)

Fitness-for-Service Criteria for Assessing the Significance of Fatigue Cracks in Offshore Structure

Abstract: Results of a research program to develop fitness-for-service criteria for assessing the significance of fatigue cracks in offshore structures are presented in five papers. Each paper describes the goals and approaches to a specific task and details the results of the study.
Date: August 1985
Creator: Cheng, Yi-Wen
Object Type: Report
System: The UNT Digital Library
Site Attenuation (open access)

Site Attenuation

Abstract: Site attenuation is a measure of performance of an open test site used at frequencies below about 1 GHz for antenna calibration and equipment emission and susceptibility testing. These sites typically consist of a large, obstruction-free ground plane and the hemisphere above it. Site attenuation of an ideal site is calculated and compared to data measured using the 30 m by 60 m NBS ground screen.
Date: November 1985
Creator: FitzGerrell, R. G.
Object Type: Report
System: The UNT Digital Library
Finline Diode Six-Port: Fundamentals and Design Information (open access)

Finline Diode Six-Port: Fundamentals and Design Information

Abstract: The preliminary design and testing of a planar circuit six-port with diode detectors is described. The planar circuit medium was chosen to be finline, and all preliminary work was done in WR-42 waveguide (18-26.5 GHz). The finline substrate was alumina, and initially commercial beam-lead diodes were bonded to the finline metalization. The goal is to design an integrated circuit which could be fabricated on one chip (with diode detectors) and used as part of a six port network analyzer in the waveguide bands above 18 GHz. Initial designs proved to b unsatisfactory because of high losses and reflections. Most of the problems have b en solved, and a usable integrated finline circuit is a good possibility for a millimeter wave six-port.
Date: December 1985
Creator: Weidman, Manly P.
Object Type: Report
System: The UNT Digital Library
Design, Evaluation, and Use of a Reverberation Chamber for Performing Electromagnetic Susceptibility/Vulnerability Measurements (open access)

Design, Evaluation, and Use of a Reverberation Chamber for Performing Electromagnetic Susceptibility/Vulnerability Measurements

Abstract: This report presents the results of work at the National Bureau of Standards, Boulder, Colorado, to carefully evaluate, document, develop (when necessary), and describe the methodology for performing radiated susceptibility/vulnerability measurements using a reverberation chamber. The report describes the reverberation chamber theory of operation, construction, evaluation, functional operation, and use for performing immunity measurements. It includes an estimate of measurement uncertainties derived empirically from test results and from comparisons with anechoic chamber measurements. Finally, it discusses the limitations and advantages of the measurement technique to assist potential users in determining the applicability for this technique to their electromagnetic compatibility (EMC) measurement needs.
Date: April 1986
Creator: Crawford, M. L. & Koepke, Galen H.
Object Type: Report
System: The UNT Digital Library
Linear Gain: Standard Antennas Below 1000 MHz (open access)

Linear Gain: Standard Antennas Below 1000 MHz

Abstract: Gain and antenna parameters related to input impedance are calculated using a computer program called HVD6. This program uses well documented equations to compute these parameters for gain-standard antennas used in relative-gain or gain-transfer measurements at frequencies below 1000 MHz. The utility of this program is that it calculates gain patterns and input impedances for linear dipoles above perfect or imperfectly conducting plane ground and in free space, and for monopoles on perfectly conducting plane ground. Examples are included to illustrate the use of the program. Uncertainties in the calculated parameters are estimated to be less than those of the measured parameters.
Date: May 1986
Creator: FitzGerrell, R. G.
Object Type: Report
System: The UNT Digital Library
Electromagnetic Compatibility and Interference Metrology (open access)

Electromagnetic Compatibility and Interference Metrology

From abstract: The material included in this report is intended for a short course on electromagnetic compatibility/interference (EMC/EMI) metrology to be offered jointly by the staff of the Fields Characterization Group (723.03) and the Interference Characterization Group (723.04) of the Electromagnetic Fields Division (723). The purpose of this short course is to present a review of some of the radiated EMC/EMI measurement methods, to which the National Bureau of Standards (NBS) at Boulder, Colorado, has made significant contributions during the past two decades.
Date: July 1986
Creator: Ma, Mark T. & Kanda, M.
Object Type: Report
System: The UNT Digital Library
Refracted-Ray Scanning (Refracted Near-Field Scanning) for Measuring Index Profiles of Optical Fibers (open access)

Refracted-Ray Scanning (Refracted Near-Field Scanning) for Measuring Index Profiles of Optical Fibers

From introduction: The purpose of this Technical Note is to describe refracted-ray scanning in detail, to analyze it as a measurement system, to document a particular system for implementing it, and to show some exemplary results.
Date: August 1981
Creator: Young, Matt
Object Type: Report
System: The UNT Digital Library
VOR Calibration Services (open access)

VOR Calibration Services

from Introduction: The National Bureau of Standards has designed, constructed, and evaluated a standard for the support of very-high-frequency omnidirectional range (VOR) air navigation aids. The standard consists of two instruments: (1) a digital waveform signal generator for the composite VOR audio waveform, and (2) a standard phasemeter based on time series analysis of this waveform. Experimental results, a statistical analysis of them, and the principal software listings are included.
Date: April 1985
Creator: Larsen, Neil T.; Vecchia, Dominic F. & Sugar, George R.
Object Type: Report
System: The UNT Digital Library
Telecommunication Technologies, Networking and Libraries (open access)

Telecommunication Technologies, Networking and Libraries

Abstract: The conference provided an overview of current and developing technologies for digital transmission of image data that are likely to have an impact on the operations of libraries and information centers or provide support for information networking. Technologies reviewed include slow-scan television, teleconferencing, and videodisc. Other papers discuss technology and standards development for computer network interconnection through hardware and software, particularly packet-switched networks; computer network protocols for library and information service applications; the structure of a national bibliographic telecommunications network; and the major policy issues involved in the regulation or deregulation of the common communications carriers industry.
Date: December 1981
Creator: Knight, Nancy H.
Object Type: Report
System: The UNT Digital Library
Proceedings of the Second International Conference on Precision Measurement and Fundamental Constants, June 8-12, 1981 (open access)

Proceedings of the Second International Conference on Precision Measurement and Fundamental Constants, June 8-12, 1981

Abstract: This volume presents the Proceedings of the Second International Conference on Precision Measurement and Fundamental Constants, held at the National Bureau of Standards in Gaithersburg, MD, from June 8-12, 1981. Like its 1970 predecessor, the Conference provided an international forum for theoretical, experimental, and applied scientists actively engaged in research on precision measurements relating to the fundamental physical constants, and on the testing of related fundamental theory. More specifically, the purpose of the Conference was to assess the present state of the precision measurement-fundamental constants field, to examine basic limitations, and to explore the prospects for future significant advances. The principal subjects covered were: frequency, wavelength, spectroscopy, quantum electrodynamics, the gas constant, x-ray interferometry, nuclidic masses, uncertainty assignment, gravitational acceleration, mass, electrical quantities, gravity, and relativity. These proceedings contain the vast majority of both the invited review papers and the contributed current research papers presented at the Conference. The new results reported at the Conference were considered for inclusion in the 1983 least-squares adjustment of the constants carried out under the auspices of the Task Group on Fundamental Constants of the Committee on Data for Science and Technology (CODATA).
Date: August 1984
Creator: Taylor, B. N. & Phillips, William D.
Object Type: Report
System: The UNT Digital Library
Precision Measurement and Calibration: Electricity: Selected Papers on the Realization and Maintenance of the Fundamental Electrical Units and Related Topics (open access)

Precision Measurement and Calibration: Electricity: Selected Papers on the Realization and Maintenance of the Fundamental Electrical Units and Related Topics

Abstract: Selected publications of the National Bureau of Standards technical staff in the field of electricity were first compiled in 1962 as a volume of the NBS Precision Measurement and Calibration Series (Electricity and Electronics, Handbook 77, Volume I); this compilation was extended in 1968 by the compilation of an additional volume in the Precision Measurement and Calibration Series (Electricity-Low Frequency, NBS Special Publication 300, Volume 3). The present volume, a further extension of these earlier compilations of selected publications in the field of electricity, includes 66 more recent papers by NBS authors and 16 abstracts of closely related papers by authors from other organizations. In view of the expansion of measurement technologies used in electricity and electromagnetism it has been necessary to reduce the range of topics for the selection of papers in the new compilation. In this connection an emphasis has been placed upon the realization and maintenance of fundamental electrical units and the related scientific advances, particularly in quantum physics. However, in the interest of completeness, three appendices also provide up-to-date bibliographies of publications by NBS authors in different areas of electromagnetism. (This book is a sequel to NBS Handbook 77-Vol. 1(1961) and NBS SP 300-Vol. 3 …
Date: October 1985
Creator: McCoubrey, Arthur O.
Object Type: Report
System: The UNT Digital Library
International Review of Environmental Specimen Banking (open access)

International Review of Environmental Specimen Banking

Abstract: In September 1983, the "8th U. S. - German Seminar of State and Planning on Environmental Specimen Banking" and the "International Review of Environmental Specimen Banking" were held at the National Bureau of Standards. At these meetings the current status of Environmental Specimen Banking Program in the U. S., Federal Republic of Germany (FRG), and other countries was presented and discussed. This publication contains a brief summary of these meetings and separate contributions describing the specimen banking activities in Canada, FRG, Japan, Sweden and the U. S.
Date: October 1985
Creator: Wise, Stephen A. & Zeisler, Rolf
Object Type: Report
System: The UNT Digital Library
Standard Reference Data Publications, 1964-1984 (open access)

Standard Reference Data Publications, 1964-1984

Abstract: The National Bureau of Standards' Office of Standard Reference Data manages a network of data centers that prepare evaluated data bases of physical and chemical properties of substances. Data bases are available in printed form, on magnetic tapes and through on-line computer networks. This document provides a comprehensive list of the products available from the National Standard Reference Data System (NSRDS) for the years 1964-1984, including indexes qualified by author, material, and property terms. Ordering information and current prices can be found at the end of this document.
Date: December 1985
Creator: Sauerwein, Joan C. & Dalton, Geraldine R.
Object Type: Report
System: The UNT Digital Library
Standard Reference Data Publications, 1985-1986 (open access)

Standard Reference Data Publications, 1985-1986

Abstract: The National Bureau of Standards' Office of Standard Reference Data manages a network of data centers that prepare evaluated databases of physical and chemical properties of substances. Databases are available in printed form, on magnetic tapes, diskettes, and through on-line computer networks. This document provides a comprehensive list of the products available from the National Standard Reference Data System (NSRDS) for the years 1985-1986, including indexes qualified by author, material, and property terms. Ordering information and current prices can be found at the end of this document.
Date: June 1987
Creator: Sauerwein, Joan C.
Object Type: Report
System: The UNT Digital Library