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Construction of a Large Transverse Electromagnetic Cell

Description: Report issued by the U.S. National Bureau of Standards discussing the construction of large electromagnetic cells. As stated in the introduction, "this instruction provides information and procedures necessary to fabricate a large transverse electromagnetic (TEM) cell to be used for experimental "electromagnetic interference" (EMI) evaluation studies" (p. 1). This report includes illustrations, and photographs.
Date: February 1979
Creator: Decker, W. F. & Wilson, W. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Report of the Forty-Fourth National Conference on Weights and Measures, 1959

Description: Report of the annual conference on weights and measures, hosted by the U.S. National Bureau of Standards in Washington D.C. It includes conference proceedings, a list of attendees, information about committees and officers, and other reports or commentaries discussed at the meetings.
Date: December 18, 1959
Creator: United States. National Bureau of Standards.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proceedings of the Conference on Accreditation of Construction Materials Testing Laboratories: 1986

Description: Abstract: A two-day Conference hosted by NBS was held in Gaithersburg, Maryland on May 14-15, 1986 to test the hypothesis that "There is a need for a coordinated methodology for accrediting construction materials testing laboratories." Construction materials include primary materials such as: cement, concrete, aggregates, rock and soil, asphalts, metals, wood and masonry. The Conference was structured to consider: (1) the status of existing laboratory evaluation and accreditation programs; (2) … more
Date: November 1987
Creator: Pielert, James H. & Spring, Curtis B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Computerization of Welding Information

Description: From abstract: The Workshop on Computerization of Welding Information, sponsored by the National Bureau of Standards and the American Welding Institute, was held August 5-6, 1986 in Knoxville, Tennessee. Forty-two welding engineers, welding managers, and computer scientists gathered to discuss the necessity and design of databases for welding information. Each subject was introduced by specialists in that area.
Date: June 1988
Creator: Siewert, T. A. & Jones, J. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Input Impedance of a Probe Antenna Exciting a TEM Cell

Description: Abstract: The input impedance of a probe antenna exciting a transverse electromagnetic (TEM) transmission line cell is formulated by a variational approach. The formulation also utilizes the results from a previous work on the field distribution inside a TEM cell excited by a vertical electrical Hertzian dipole. The final result of imoedance is shown to consist of two distinct terms, which are respectively contributed by the ordinary rectangular waveguide and the gap perturbation. Numerical res… more
Date: April 1982
Creator: Wilson, Perry F.; Chang, David C. & Ma, Mark T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Picosecond Time Difference Measurements Utilizing CAMAC-Based ANSI/IEEE-488 Data Acquisition Hardware : Operating Manual IE3, Version 1.0

Description: Abstract: Automated time-difference measurements at the picosecond level have been achieved. The system described combines the best properties of three common methods: the single heterodyne measurement technique, the frequency divider, and the dual-mixer time-difference measurement system. This particular system combines two instrumentation standards, ANSI/IFEE-583 and ANSI/IEEE-488 with new, modular dual-mixer time-difference measurement hardware. The modular, standardized hardware together wi… more
Date: August 1983
Creator: Glaze, D. J. & Stein, S. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Electric and Magnetic Field Sensor for Simultaneous Electromagnetic Near-Field Measurements -- Theory

Description: Abstract: This paper describes the theory of a single sensor to perform simultaneous electric and magnetic near-field measurements. The theory indicates that it is possible to obtain the magnetic-loop and electric-dipole currents using a loop terminated with identical loads at diametrically opposite points. The theory also indicates that it is possible to obtain an ideal load impedance for achieving equal electric and magnetic field responses of the loop. Preliminary experiments have been perfo… more
Date: April 1983
Creator: Kanda, Motohisa
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Characteristics of Iris-Fed Millimeterwave Rectangular Microstrip Patch Antennas

Description: From introduction: The fabrication of various iris-fed millimeterwave rectangular microstrip patch antennas is described. A model is proposed to describe the iris-fed antenna. Irises ranging in size from 15 percent of the area of the patch to the fully open waveguide are used to couple energy into the antenna. Resonance of the antenna is observed to be insensitive to the size of the iris for irises up to 115 percent of the size of the patch. A study is also made of th? relationship of coupling … more
Date: October 1983
Creator: Greenlee, D. H.; Kanda, Motohisa & Chang, David C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optical Time-Domain Reflectometer Performance and Calibration Studies

Description: from Introduction: The measurement accuracy of the optical time-domain reflectometer (OTDR) is restricted in some applications by a limited operational dynamic range and by a lack of standardized test procedures. In an effort to better understand these restrictions, we have measured the range of linearity of some avalanche photodiodes used as backscatter detectors. Also, the effect of input launch conditions is examined and a possible standardized OTDR test procedure is proposed. Using these su… more
Date: June 1983
Creator: Danielson, B. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reference Flat Pulse Generator

Description: Introduction: A reference step-like pulse generator is described which has been developed at NBS. This generator can be used for accurately characterizing the step response of various kinds of trap ient recording equipment (oscilloscopes, waveform recorders, transient digitizers, etc.). Basic design principles are given as well as complete circuit diagrams and descriptions. An analysis of the output stage of the generator is presented together with the circuit models for developing a time-domai… more
Date: October 1983
Creator: Andrews, J. R.; Bell, B. A. & Baldwin, E. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Introduction to STARPAC: the Standards Time Series and Regression Package

Description: From preface: STARPAC documentation is being published as a series of Technical Notes. This Note is the first in the series. It gives an overview of the STARPAC library, defines conventions used in the documentation, provides an example using STARPAC subroutines, and presents general background material. This Note includes information which is essential for using the STARPAC library, and users should be familiar with its contents before attempting to use any STARPAC subroutine.
Date: October 1983
Creator: Donaldson, Janet R. & Tryon, Peter V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nonlinear Least Squares Regression Using STARPAC: The Standards Time Series and Regression Package

Description: From preface: This Note documents 16 subroutines for nonlinear least squares regression. Twelve of these compute the least squares estimates, performing either weighted or unweighted analysis with either numerically approximated or user-supplied (analytic) derivatives. The other four are user-callable subroutines for two procedures used within the estimation code: the first selects optimum step sizes for approximating the partial derivatives of the model; and the second checks the validity of a… more
Date: October 1983
Creator: Donaldson, Janet R. & Tryon, Peter V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Equation of State for Fluid Ethylene

Description: Abstract: A thermodynamic property formulation for ethylene, developed as a part of a joint industry-government project, is presented. The formulation includes an equation of state, vapor pressure equation, and equation for the ideal gas heat capacity. The coefficients were determined by a least squares fit of selected experimental data. Comparisons of property values calculated using the equation of state with measured values are given. The equation of state is not valid in the critical region… more
Date: July 1981
Creator: McCarty, Robert D. & Jacobsen, Richard T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of Optical Fiber Bandwidth in the Frequency Domain

Description: Abstract: The design, evaluation, and performance of a system for determining the magnitude of the transfer function (hence, the bandwidth) of a multimode optical fiber are presented. The system operates to about 1450 MHz using a tracking generator/spectrum analyzer combination for narrowband detection. It is constructed, almost entirely, from commercially available components. The system is less complex and easier to use than an equivalent time domain system and the measurement precision is co… more
Date: September 1981
Creator: Day, G. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermophysical Properties of Isobutane from 114 to 700 K at Pressures to 70 MPa

Description: Abstract: Using a modified version of the nonanalytic equation of state, thermophysical properties of isobutane are derived from physical properties data and are tabulated at integral temperatures over the entire range of fluid states from 114 to 700 K along isobars at pressures to 70 MPa. Results include dielectric constants, densities, enthalpies, entropies, equation of state, internal energies, isobars, isochores, isotherms, Joule-Thomson inversion, heats of vaporization, melting line, ortho… more
Date: January 1982
Creator: Goodwin, Robert D. & Haynes, William M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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