On the identification of piecewise constant coefficients in optical diffusion tomography by level set

In this paper, we propose a level set regularization approach combined with a split strategy for the simultaneous identification of piecewise constant diffusion and absorption coefficients from a finite set of optical tomography data (Neumann-to-Dirichlet data). This problem is a high nonlinear inverse problem combining together the exponential and mildly ill-posedness of diffusion and absorption coefficients, respectively. We prove that the parameter-to-measurement map satisfies sufficient conditions (continuity in the L1 topology) to guarantee regularization properties of the proposed level set approach. On the other hand, numerical tests considering different configurations bring new ideas on how to propose a convergent split strategy for the simultaneous identification of the coefficients. The behavior and performance of the proposed numerical strategy is illustrated with some numerical examples

Equipartition of energy for nonautonomous wave equations

Consider wave equations of the form u (t) + A2u(t) = 0 with A an injective selfadjoint operator on a complex Hilbert space H. The kinetic, potential, and total energies of a solution u are K(t) = ∥u\u27(t)∥2; P(t) = ∥Au(t)∥2; E(t) = K(t) + P(t): Finite energy solutions are those mild solutions for which E(t) is finite. For such solutions E(t) = E(0), that is, energy is conserved, and asymptotic equipartition of energy lim/t→±∞ K(t) = lim/t→±∞P(t) = E(0)/2 holds for all finite energy mild solutions iff eitA → 0 in the weak operator topology. In this paper we present the first extension of this result to the case where A is time dependent

Tools for detecting insect semiochemicals: a review.

Made available in DSpace on 2018-08-17T00:52:47Z (GMT). No. of bitstreams: 1 Brezolin2018ArticleToolsForDetectingInsectSemioch.pdf: 2919852 bytes, checksum: f2a2fc74843de29440e64e7c1d641761 (MD5) Previous issue date: 2018-08-16bitstream/item/181538/1/Brezolin2018-Article-ToolsForDetectingInsectSemioch.pdfNa publicação: Maria Carolina Blassioli-Moraes