ARTIFICIAL BOUNDARY CONDITIONS AND DOMAIN TRUNCATION IN ELECTRICAL IMPEDANCE TOMOGRAPHY. PART I: THEORY AND PRELIMINARY RESULTS

作者：Calvetti Daniela^*; Hadwin Paul J; Huttunen Janne M J; Isaacson David; Kaipio Jari P; McGivney Debra; Somersalo Erkki; Volzer Joseph

来源：Inverse Problems and Imaging, 2015, 9(3): 749-766.

DOI：10.3934/ipi.2015.9.749

• Domain decomposition
• Dirichlet-to-Neumann
• Steklov-Poincare
• coercivity
• electrode model

Artificial boundary conditions have long been an active research topic in numerical approximation of scattering waves: The truncation of the computational domain and the assignment of the conditions along the fictitious boundary must be done so that no spurious reflections occur. In inverse boundary value problems, a similar problem appears when the estimation of the unknowns is restricted to a domain that represents the whole domain of the solutions of a partial differential equation with unknown coefficient. This problem is significantly more challenging than general scattering problems, because the coefficients representing the unknown material parameter of interest are not known in the truncated portion and assigning suitable condition on the fictitious boundary is part of the problem also. The problem is addressed by defining a Dirichlet-to-Neumann map, or Steklov-Poincare map, on the boundary of the domain truncation. In this paper we describe the procedure, provide a theoretical justification and illustrate with computed examples the limitations of imposing fixed boundary condition. Extensions of the proposed approach will be presented in a sequel article.

• 出版日期2015-8