E.S. Chalhoub, H.F. de Campos Velho (2002): Estimation of Internal Sources in Natural Waters using Remote Sensing Data, 4th International Conference on Inverse Problems in Engineering: Theory and Practice ( ICIPE-2002), May 26-31, Angra dos Reis (RJ), Brazil. (submitted).

Abstract: An inverse analysis for the estimation of internal sources in natural waters, using remote sensing data, is presented. The analisis involves a forward model that utlizes an analytical discrete-ordinates method for solving the radiative transfer equation [1, 2], and an inverse model which contains an algorithm for least squares estimation that is iteratively solved for retrieving the desired optical properties by using the Levenberg-Marquardt optimizer [3-5]. The experimental data are simulated with synthetic data (exit radiances) that are calculated at the surface of the water and corrupted with noise. The results show that the internal sources can be recovered with good accuracy, even for high noisy data.

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[2] E.S. Chalhoub, R.D.M. Garcia (2000): The Equivalence between Two Techniques of Angular Interpolation for the Discrete-ordinates Method, Journal of Quantitative Spectroscopy & Radiative Transfer, 64, 517-535.

[3] K.A. Levenberg (1944): A Method for the Solution of Certain Problems in Least-squares Estimation, Quaterly of Applied Mathematics, 2, 164-168.

[4] D. Marquardt (1963): An Algorithm for Least-squares Estimation of Nonlinear Parameters, Journal of the Society for Industrial and Apllied Mathematics, 11, 431-441.

[5] IMSL (1991): IMSL Math/Library Users Manual, Version 2.0, Houston: IMSL.