The comparative study of two globally convergent numerical methods for acoustic tomography is carried out in two dimensions. These are the boundary control method and the quasi-reversibility method. The novelty is that in the latter a nonlinear inverse problem is reduced to a family of the linear integral equations of the first kind via the Lavrentiev approach and this reduction is used within the quasi-reversibility method. The analysis of its stability is carried out via Carleman estimates. The computational effectiveness of these methods is tested in the numerical experiments with the smooth and discontinuous coefficients to be recovered from the tomographic data.
翻译:对两种全球趋同的声波断层摄影数字方法的比较研究分两个方面进行,即边界控制法和准反向法,新颖之处是,在后一种情况下,非线性反问题通过Lavrentiev 方法变成第一种线性整体方程的组合,这种减少是在准反向方法中使用的。通过Carleman 估计来分析其稳定性。这些方法的计算效力在数字试验中经过测试,从图象数据中回收的平滑和不连续系数。