Algoritmos ART para a Estimativa do Coeficiente de Absorção com Feixes Divergentes usando certas Funções de Bregman
DOI:
https://doi.org/10.5540/tema.2007.08.02.0181Abstract
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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