Under-relaxed quasi-Newton acceleration for an inverse fixed-point problem coming from Positron Emission Tomography

Autor(es)

dos Santos, Tiara Martini ^[1] ; Reips, Louise ^[2] ; Martinez, Jose Mario ^[3]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Inst Sci & Technol, Ave Cesare Mansueto Giulio Lattes 1201, BR-12247014 Sao Jose Dos Campos - Brazil

^[2] Univ Fed Santa Catarina, Dept Math, Blumenau, SC - Brazil

^[3] Univ Estadual Campinas, Dept Appl Math, IMECC, UNICAMP, Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Inverse and Ill-Posed Problems; v. 26, n. 6, p. 755-770, DEC 2018.
• Citações Web of Science: 0

Resumo

Quasi-Newton acceleration is an interesting tool to improve the performance of numerical methods based on the fixed-point paradigm. In this paper, a briefly description of the compartmental model employed for a typical task in perfusion imaging is presented. Next, a quasi-Newton strategy for accelerating the convergence of fixed-point iterations is analyzed. For that, classical secant updates are considered. Finally, the quasi-Newton strategy is applied on the practical problem of represent the kinetic behavior of a PET (Positron Emission Tomography) tracer during cardiac perfusion. The performance of the method when applied to real data problems is illustrated numerically. (AU)

• Processo FAPESP: 12/10444-0 - Um novo software integrado para sistemas não lineares
• Beneficiário: Tiara Martini dos Santos
• Modalidade de apoio: Bolsas no Brasil - Doutorado