Search for dissertations about: "adjoint problem"
Showing result 16 - 20 of 37 swedish dissertations containing the words adjoint problem.
-
16. Resolvent Estimates and Bounds on Eigenvalues for Schrödinger and Dirac Operators
Abstract : This thesis concerns the spectral theory of Schrödinger and Dirac operators. The main results relate to the problems of estimating perturbed eigenvalues. The thesis is based on four papers.The first paper focuses on the problem of localization of perturbed eigenvalues for multidimensional Schrödinger operators. READ MORE
-
17. Time-Domain Inverse Electromagnetic Scattering using FDTD and Gradient-based Minimization
Abstract : The thesis addresses time-domain inverse electromagneticscattering for determining unknown characteristics of an objectfrom observations of the scattered .eld. Applications includenon-destructive characterization of media and optimization ofmaterial properties, for example the design of radar absorbingmaterials. READ MORE
-
18. Regularization methods for solving Cauchy problems for elliptic and degenerate elliptic equations
Abstract : In this thesis, we study Cauchy problems for the elliptic and degenerate elliptic equations. These problems are ill-posed. We split the boundary of the domain into two parts. On one of them, say Γ0, we have available Cauchy data and on remaining part Γ1 we introduce unknown Robin data. READ MORE
-
19. Shape and material optimization for antenna applications
Abstract : In this thesis, a gradient-based method for shape and material optimization fortwo antenna applications is presented: minimization of the active reflectioncoefficient for conformal array antennas; and minimization of the totalscattering cross section for cylindrical scatterers. The sensitivity of theobjective function with respect to changes of the shape and material of the geometry isexpressed in terms of the original field problem and an adjoint field problem. READ MORE
-
20. The Dirac Operator; From Numerics to the Theory of G-convergence
Abstract : We consider two main issues concerning the Dirac operator, the first is widely known as the appearance of spurious eigenvalues within the spectrum. The second is the study of the asymptotic behavior of the eigenvalues for a family of Dirac operators with oscillatory potential added to the Coulomb-Dirac Hamiltonian. READ MORE