A Stable Iterative Direct Sampling Method for Elliptic Inverse Problems with Partial Cauchy Data
Bangti Jin, Fengru Wang, Jun Zou
TL;DR
This work introduces a stable Iterative Direct Sampling Method (IDSM) for elliptic inverse problems with partial Cauchy data. By combining data completion, a heterogeneously regularized Dirichlet-to-Neumann map, and a stabilization-correction scheme, the method restores near-orthogonality of probing functions, suppresses noise-induced artifacts, and guarantees stability through a uniformly bounded resolver. The approach is validated across diverse models, including EIT, DOT, and cardiac electrophysiology, demonstrating robust localization of inhomogeneities under partial data and significant measurement noise. The results highlight practical efficiency (tens of PDE solves) and broad applicability to nonlinear and multi-physics settings, with clear guidance on algorithmic parameters and stopping indicators derived from the damping factor behavior.
Abstract
We develop a novel iterative direct sampling method (IDSM) for solving linear or nonlinear elliptic inverse problems with partial Cauchy data. It integrates three innovations: a data completion scheme to reconstruct missing boundary information, a heterogeneously regularized Dirichlet-to-Neumann map to enhance the near-orthogonality of probing functions, and a stabilization-correction strategy to ensure the numerical stability. The resulting method is remarkably robust with respect to measurement noise, is flexible with the measurement configuration, enjoys provable stability guarantee, and achieves enhanced resolution for recovering inhomogeneities. Numerical experiments in electrical impedance tomography, diffuse optical tomography, and cardiac electrophysiology show its effectiveness in accurately reconstructing the locations and geometries of inhomogeneities.
