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Electromagnetic Radiation (EMR) coupling to complex systems : aperture coupling into canonical cavities in reverberant and anechoic environments and model validation.

Description: Mode-stirred chamber and anechoic chamber measurements were made on two sets of canonical test objects (cylindrical and rectangular) with varying numbers of thin slot apertures. The shielding effectiveness was compared to determine the level of correction needed to compensate the mode-stirred data to levels commensurate with anechoic data from the same test object.
Date: December 1, 2007
Creator: Charley, Dawna R. & Higgins, Matthew B.
Partner: UNT Libraries Government Documents Department

Measurement and modeling of transfer functions for lightning coupling into the Sago mine.

Description: This report documents measurements and analytical modeling of electromagnetic transfer functions to quantify the ability of cloud-to-ground lightning strokes (including horizontal arc-channel components) to couple electromagnetic energy into the Sago mine located near Buckhannon, WV. Two coupling mechanisms were measured: direct and indirect drive. These transfer functions are then used to predict electric fields within the mine and induced voltages on conductors that were left abandoned in the sealed area of the Sago mine.
Date: April 1, 2007
Creator: Morris, Marvin E. & Higgins, Matthew B.
Partner: UNT Libraries Government Documents Department

Assessment of the non-destructive nature of PASD on wire insulation integrity.

Description: The potential of a new cable diagnostic known as Pulse-Arrested Spark Discharge technique (PASD) is being studied. Previous reports have documented the capability of the technique to locate cable failures using a short high voltage pulse. This report will investigate the impact of PASD on the sample under test. In this report, two different energy deposition experiments are discussed. These experiments include the PASD pulse ({approx}6 mJ) and a high energy discharge ({approx}600 mJ) produced from a charged capacitor source. The high energy experiment is used to inflict detectable damage upon the insulators and to make comparisons with the effects of the low energy PASD pulse. Insulator breakdown voltage strength before and after application of the PASD pulse and high energy discharges are compared. Results indicate that the PASD technique does not appear to degrade the breakdown strength of the insulator or to produce visible damage. However, testing of the additional materials, including connector insulators, may be warranted to verify PASDs non-destructive nature across the full spectrum of insulators used in commercial aircraft wiring systems.
Date: September 1, 2003
Creator: Lockner, Thomas Ramsbeck; Peña, Gary Edward; Schneider, Larry X.; Higgins, Matthew B. & Glover, Steven Frank
Partner: UNT Libraries Government Documents Department

Final report on development of Pulse Arrested Spark Discharge (PASD) for aging aircraft wiring application.

Description: Pulsed Arrested Spark Discharge (PASD) is a Sandia National Laboratories Patented, non-destructive wiring system diagnostic that has been developed to detect defects in aging wiring systems in the commercial aircraft fleet. PASD was previously demonstrated on relatively controlled geometry wiring such as coaxial cables and shielded twisted-pair wiring through a contract with the U.S. navy and is discussed in a Sandia National Laboratories report, SAND2001-3225 ''Pulsed Arrested Spark Discharge (PASD) Diagnostic Technique for the Location of Defects in Aging Wiring Systems''. This report describes an expansion of earlier work by applying the PASD technique to unshielded twisted-pair and discrete wire configurations commonly found in commercial aircraft. This wiring is characterized by higher impedances as well as relatively non-uniform impedance profiles that have been found to be challenging for existing aircraft wiring diagnostics. Under a three year contract let by the Federal Aviation Administration, Interagency Agreement DTFA-03-00X90019, this technology was further developed for application on aging commercial aircraft wiring systems. This report describes results of the FAA program with discussion of previous work conducted under U.S. Department of Defense funding.
Date: September 1, 2006
Creator: Lockner, Thomas Ramsbeck; Howard, R. Kevin; Peña, Gary Edward; Schneider, Larry X.; Higgins, Matthew B. & Glover, Steven Frank
Partner: UNT Libraries Government Documents Department

Capacitance and effective area of flush monopole probes.

Description: Approximate formulas are constructed and numerical simulations are carried out for electric field derivative probes that have the form of flush mounted monopoles. Effects such as rounded edges are included. A method is introduced to make results from two-dimensional conformal mapping analyses accurately apply to the three-dimensional axisymmetric probe geometry
Date: August 1, 2004
Creator: Warne, Larry Kevin; Johnson, William Arthur; Morris, Marvin E.; Basilio, Lorena I.; Lehr, Jane Marie & Higgins, Matthew B.
Partner: UNT Libraries Government Documents Department