Abstract
The problem of determining capillary pressure functions from centrifuge data leads to an integral equation of the form ?xa K (x.t) f(t)dt = g(x). x ? [a.b]. where the kernel K is known exactly and given by the underlying mathematical model. g is only known with a limited degree of accuracy in a finite and discrete set of points x1.....XM. However, the sought function f(t) is continuous. By the nature of the right-hand side, g(x), equation (1) is a discrete inverse problem which is ill-posed in the sense of Hadamard [9]. By a parameterization of the sought function, equation (1) reduces to a system of linear equations of the form Ac = b + e. where b is the observation vector and A arises from discretization of the forward problem. e is the error vector associated with b, and c contains the model parameters. The matrix A is usually ill-conditioned. The ill-conditioning is closely connected to the parameterization of the problem [23]. In this paper a semi-iterative regularization method for solving the Volterra integral equation in the e2-norm, namely, Brakhage's v-method [2], is investigated. The iterative method is tested on synthetically generated, and on experimental data.
Original language | English |
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Pages (from-to) | 207-224 |
Number of pages | 18 |
Journal | Computational Geosciences |
Volume | 6 |
Issue number | 2 |
DOIs | |
Publication status | Published - Jun 2002 |
Keywords
- Capillary pressure
- Ill-posed
- Inverse
- Regularization
- Semi-iterative