Non Linear Conjugate Gradient
Abstract
Software that simulates and inverts electromagnetic field data for subsurface electrical properties (electrical conductivity) of geological media. The software treats data produced by a time harmonic source field excitation arising from the following antenna geometery: loops and grounded bipoles, as well as point electric and magnetic dioples. The inversion process is carried out using a nonlinear conjugate gradient optimization scheme, which minimizes the misfit between field data and model data using a least squares criteria. The software is an upgrade from the code NLCGCS_MP ver 1.0. The upgrade includes the following components: Incorporation of new 1 D field sourcing routines to more accurately simulate the 3D electromagnetic field for arbitrary geologic& media, treatment for generalized finite length transmitting antenna geometry (antennas with vertical and horizontal component directions). In addition, the software has been upgraded to treat transverse anisotropy in electrical conductivity.
 Authors:
 Publication Date:
 Research Org.:
 Lawrence Berkeley National Laboratory
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1230583
 Report Number(s):
 NLCGCS_MPV3.0; 001365UNIXW01
R&D Project: B&R number:KC0303010; Project number:468113; LBNL CR2265
 DOE Contract Number:
 DEAC0376SF00098
 Resource Type:
 Software
 Software Revision:
 01
 Software Package Number:
 001365
 Software Package Contents:
 Media Directory; Software Abstract; Media includes Source Code, Installation Instructions, ReadMe File; Sample Problem Input Data and Sample Problem Output Data;/1 CD ROM
 Software CPU:
 UNIXW
 Open Source:
 No
 Source Code Available:
 Yes
 Country of Publication:
 United States
Citation Formats
Newman, Gregory A., and Commer, Michael. Non Linear Conjugate Gradient.
Computer software. Vers. 01. USDOE. 17 Nov. 2006.
Web.
Newman, Gregory A., & Commer, Michael. (2006, November 17). Non Linear Conjugate Gradient (Version 01) [Computer software].
Newman, Gregory A., and Commer, Michael. Non Linear Conjugate Gradient.
Computer software. Version 01. November 17, 2006.
@misc{osti_1230583,
title = {Non Linear Conjugate Gradient, Version 01},
author = {Newman, Gregory A. and Commer, Michael},
abstractNote = {Software that simulates and inverts electromagnetic field data for subsurface electrical properties (electrical conductivity) of geological media. The software treats data produced by a time harmonic source field excitation arising from the following antenna geometery: loops and grounded bipoles, as well as point electric and magnetic dioples. The inversion process is carried out using a nonlinear conjugate gradient optimization scheme, which minimizes the misfit between field data and model data using a least squares criteria. The software is an upgrade from the code NLCGCS_MP ver 1.0. The upgrade includes the following components: Incorporation of new 1 D field sourcing routines to more accurately simulate the 3D electromagnetic field for arbitrary geologic& media, treatment for generalized finite length transmitting antenna geometry (antennas with vertical and horizontal component directions). In addition, the software has been upgraded to treat transverse anisotropy in electrical conductivity.},
doi = {},
year = 2006,
month = ,
note =
}

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Nonlinear Conjugate Gradient TimeDomain Controlled Inversion Source
Software that simulates and inverts timedomain electromagnetic field data for subsurface electrical properties (electrical conductivity) of geological media. The software treats data produced by a stepwise source signal from either galvanic (grounded wires) or inductive (magnetic loops) sources. The inversion process is carried inductive (magnetic loops) sources. The inversion process is carried out using a nonlinear conjugate gradient optimization scheme, which minimizes the misfit between field data and model data using a least squares criteria. The software is an upgrade from the code TEM3D ver. 2.0. The upgrade includes the following components: (1) Improved (faster)memory access during gradient computation. (2)more »
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