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Aerial Radiometric and Magnetic Survey: Eastville/Norfolk National Topographic Map, North Carolina/Virginia/Maryland

Description: From abstract: "The results of analyses of the airborne gamma radiation and total magnetic field survey flown for the region identified as the Eastville/Norfolk National Topographic Maps, numbered NJ18-10 for Norfolk and NJ18-8,11 for Eastville, are presented in this report."
Date: 1989
Creator: Geodata International
Location: None
Partner: UNT Libraries Government Documents Department
open access

Aerial Gamma Ray and Magnetic Survey, Final Report. Volume 1: Rice Lake Quadrangle (Wisconsin), Iron Mountain Quadrangle (Wisconsin/Michigan), Eau Claire Quadrangle (Wisconsin/Minnesota), and Green Bay Quadrangle (Wisconsin)

Description: A high sensitivity airborne radiometric and magnetic survey of the Rice Like, Iron Mountain, Eau Claire and Green Bay 1:250,000 NMTS Quadrangles within the states of Wisconsin, Michigan, and Minnesota. A total of 10,340 line miles of high sensitivity radiometric and magnetic data were collected within these quadrangles. Traverse lines were flown at a spacing of 3.125 miles in an east/west direction at a 18.375 miles seperation. All data were collected utilizing a fixed wing aircraft and over 3,500 cubic inches of Nal crystal detector. Magnetometer data were collected utilizing a high sensitivity proton magnetometer. Data were recorded digitally at 1.0 second intervals aboard the aircraft. Navigation was performed using both visual and doppler techniques. All data presented in this report as corrected profiles of all radiometric variables, magnetic data, radar and barometric altimeter data, air temperature and airborne bismuth contributions. Radiometric data presented are corrected for Comptron Scatter, altitude dependence and atmospheric Bismuth. These data are also presented on microfiche, and digital magnetic tapes. In addition, anomaly maps and inerpretation maps are presented in relating known geology or soil distribution to the corrected radiometric magnetic data.
Date: April 1987
Creator: GeoMetrics, Inc.
Location: None
Partner: UNT Libraries Government Documents Department
open access

Electromagnetic Compatibility and Interference Metrology

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

Linear Gain: Standard Antennas Below 1000 MHz

Description: 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.
Partner: UNT Libraries Government Documents Department
open access

A Statistical Characterization of Electroexplosive Devices Relevant to Electromagnetic Compatibility Assessment

Description: 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 which is crucial for evaluating the effects of currents induced by impulsive electromagnetic fields of short duration relative to the EEDs thermal time constant.
Date: May 1986
Creator: Friday, Dennis S. & Adams, John W.
Partner: UNT Libraries Government Documents Department
open access

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

Description: 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.
Partner: UNT Libraries Government Documents Department
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