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Title: Topology optimization for design of coaxial cables.

Abstract

Abstract not provided.

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1425291
Report Number(s):
SAND2017-1995C
651273
DOE Contract Number:
AC04-94AL85000
Resource Type:
Conference
Resource Relation:
Conference: Proposed for presentation at the SIAM conference on Computational Science and Engineering in Atlanta, GA.
Country of Publication:
United States
Language:
English

Citation Formats

Cyr, Eric C, von Winckel, Gregory John, Gardiner, Thomas Anthony, Kouri, Drew Philip, Miller, Sean, and Shadid, John N. Topology optimization for design of coaxial cables.. United States: N. p., 2017. Web.
Cyr, Eric C, von Winckel, Gregory John, Gardiner, Thomas Anthony, Kouri, Drew Philip, Miller, Sean, & Shadid, John N. Topology optimization for design of coaxial cables.. United States.
Cyr, Eric C, von Winckel, Gregory John, Gardiner, Thomas Anthony, Kouri, Drew Philip, Miller, Sean, and Shadid, John N. Wed . "Topology optimization for design of coaxial cables.". United States. doi:. https://www.osti.gov/servlets/purl/1425291.
@article{osti_1425291,
title = {Topology optimization for design of coaxial cables.},
author = {Cyr, Eric C and von Winckel, Gregory John and Gardiner, Thomas Anthony and Kouri, Drew Philip and Miller, Sean and Shadid, John N.},
abstractNote = {Abstract not provided.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}

Conference:
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  • Four-terminal-pair devices which must be operated at liquid helium temperatures can only be connected to the measurement setup with relatively long, thin cables. This unfortunately leads to a large increase of the errors introduced by these cables. Some considerations are presented which allow these errors to be reduced as is necessary for precision measurements.
  • Radio-frequency signals simulating electrical interference ranging from 50 kHz to 50 MHz were applied to the shields of the input cable system (two solid- shielded, mineral-insulated cables approximately 6 m long) of a wide-band (approximately 60 MHz) differential preamplifier for fission counters to determine the common-mode rejection. Results show that differences in electrical properties and shielding characteristics of the two input coaxial cables along with end effects produced by an unbalanced sensor severely degrade the rejection capability of the differential preamplifier. At 1 MHz, the common-mode rejection without input cables is approximately --70 dB; this is reduced to approximately --more » 10 dB when measured with the rf signal applied to the surface of the input cable shields. Measurements of the shielding characteristics of the input cables showed resonances at test frequencies greater than 2 MHz. A ferrite core was installed in the input assembly to increase the impedance of the shields and to permit termination of the coaxial line consisting of the input cable shields and the protective metal conduit for the input cables. This assembly eliminated all resonances below 20 MHz. The increased impedance also reduced the amplitude of the shield currents, resulting in an increase in the shielding effectiveness of the input cables without affecting the signal transmission of the cables. (auth)« less
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