Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 2834
Book Description
Monthly Catalog of United States Government Publications
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 2834
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 2834
Book Description
Monthly Catalog of United States Government Publications, Cumulative Index
Author: United States. Superintendent of Documents
Publisher:
ISBN:
Category : United States
Languages : en
Pages : 1348
Book Description
Publisher:
ISBN:
Category : United States
Languages : en
Pages : 1348
Book Description
Monthly Catalog of United States Government Publications
Author: United States. Superintendent of Documents
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1320
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1320
Book Description
Catalog of the United States Geological Survey Library
Author:
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 782
Book Description
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 782
Book Description
Convergence of Iterative Methods Applied to Large Overdetermined Linear and Nonlinear Systems of Equations Using Least Squares
Author: Charles O. Stearns
Publisher:
ISBN:
Category : Chebyshev polynomials
Languages : en
Pages : 20
Book Description
Solutions are obtained to large overdetermined systems of equations. Both nonlinear and linear systems are considered. The nonlinear system represents a dipole model of the earth's geomagnetic field, which is generated from spherical harmonic coefficients. This system of 64 unknowns and 1836 equations is solved by a maximum neighborhood method, which is an optimum interpolation between the well known Taylor's series and steepest descent methods. The original given values of the generated field are as large as 60,000 gamma, whereas a rms residual of 27.9 gamma is obtained with 173 iterations. The linear system of equations represents dipole changes required to account for the earth's secular change field which is generated from spherical harmonic coefficients. The dipole parameters computed from the nonlinear model are used as input parameters. The system contains 64 unknowns and 612 equations and is solved using a Chebyshev polynomial iterative method. These results are compared to results obtained by a direct solution of the normal equations of the system and results obtained by a pseudo-inverse method using a modified Gram-Schmidt factorization. Although the latter two methods give smaller rms values than the iterative method, the results of the iterative method are more reasonable in view of known properties of the results. The generated field has a rms value of 45 gamma per year. An rms residual of 2.5 gamma per year was obtained after 25,000 iterations.
Publisher:
ISBN:
Category : Chebyshev polynomials
Languages : en
Pages : 20
Book Description
Solutions are obtained to large overdetermined systems of equations. Both nonlinear and linear systems are considered. The nonlinear system represents a dipole model of the earth's geomagnetic field, which is generated from spherical harmonic coefficients. This system of 64 unknowns and 1836 equations is solved by a maximum neighborhood method, which is an optimum interpolation between the well known Taylor's series and steepest descent methods. The original given values of the generated field are as large as 60,000 gamma, whereas a rms residual of 27.9 gamma is obtained with 173 iterations. The linear system of equations represents dipole changes required to account for the earth's secular change field which is generated from spherical harmonic coefficients. The dipole parameters computed from the nonlinear model are used as input parameters. The system contains 64 unknowns and 612 equations and is solved using a Chebyshev polynomial iterative method. These results are compared to results obtained by a direct solution of the normal equations of the system and results obtained by a pseudo-inverse method using a modified Gram-Schmidt factorization. Although the latter two methods give smaller rms values than the iterative method, the results of the iterative method are more reasonable in view of known properties of the results. The generated field has a rms value of 45 gamma per year. An rms residual of 2.5 gamma per year was obtained after 25,000 iterations.
An Introduction to Geomagnetic Instruments and Observing
Author: Wallace Hall Campbell
Publisher:
ISBN:
Category : Geomagnetism
Languages : en
Pages : 52
Book Description
Publisher:
ISBN:
Category : Geomagnetism
Languages : en
Pages : 52
Book Description
Catalog of the United States Geological Survey Library
Author: U.S. Geological Survey Library
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 764
Book Description
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 764
Book Description
The United States Department of Commerce Publications, Catalog and Index Supplement
Author: United States. Department of Commerce
Publisher:
ISBN:
Category : Commerce
Languages : en
Pages : 692
Book Description
Publisher:
ISBN:
Category : Commerce
Languages : en
Pages : 692
Book Description
Earth Sciences Laboratories Progress Report, Fiscal Year 1970
Author: Leroy Romney Alldredge
Publisher:
ISBN:
Category : Earth sciences
Languages : en
Pages : 28
Book Description
Publisher:
ISBN:
Category : Earth sciences
Languages : en
Pages : 28
Book Description
Book Catalog of the Library and Information Services Division: Shelf List catalog
Author: Environmental Science Information Center. Library and Information Services Division
Publisher:
ISBN:
Category : Earth sciences
Languages : en
Pages : 578
Book Description
Publisher:
ISBN:
Category : Earth sciences
Languages : en
Pages : 578
Book Description