Algoritmos ART para a Estimativa do Coeficiente de Absorção com Feixes Divergentes usando certas Funções de Bregman

Authors

  • M.J. Berrocal
  • R.F. Carita Montero

DOI:

https://doi.org/10.5540/tema.2007.08.02.0181

Abstract

Consideramos uma classe de algoritmos tipo ART (Algebraic Reconstruction Technique) empregando certas funções de Bregman, para a estimativa do coeficiente de absorção com feixes divergentes de poucas vistas onde o n´umero de incógnitas é maior ao n´umero de dados. O funcional de Bregman usado está relacionado às entropias estudadas por Shannon, Harvda-Charvát e Sharma-Taneja. Este funcional depende de certos parâmetros r e s. Com este funcional nós construímos uma família de distâncias de Bregman para ser empregada nos algoritmos ART. Neste trabalho procuram-se os valores ótimos dos parâmetros r quando s ! 1, que ofereçam os melhores resultados para a estimativa dos coeficientes de absorção. Casos testes são apresentados, empregando dados com ruídos randômicos.

References

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Published

2007-08-13

How to Cite

Berrocal, M., & Carita Montero, R. (2007). Algoritmos ART para a Estimativa do Coeficiente de Absorção com Feixes Divergentes usando certas Funções de Bregman. Trends in Computational and Applied Mathematics, 8(2), 181–190. https://doi.org/10.5540/tema.2007.08.02.0181

Issue

Vol. 8 No. 2 (2007)

Section

Original Article

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