This paper considers the attenuated Westervelt equation in pressure formulation. The attenuation is by various models proposed in the literature and characterised by the inclusion of non-local operators that give power law damping as opposed to the exponential of classical models. The goal is the inverse problem of recovering a spatially dependent coefficient in the equation, the parameter of nonlinearity $\kappa(x)$, in what becomes a nonlinear hyperbolic equation with nonlocal terms. The overposed measured data is a time trace taken on a subset of the domain or its boundary. We shall show injectivity of the linearised map from $\kappa$ to the overposed data used to recover it and from this basis develop and analyse Newton-type schemes for its effective recovery.
翻译:本文在压力配方中考虑了衰减的Westervelt 等式。 衰减是由文献中提议的各种模型进行的, 其特点是将非本地操作者包括在内, 使权力法与古典模型的指数相对拉动。 目标是在方程式中恢复一个空间依赖系数, 即非线性参数$\kappa( x)$( x), 成为非线性双曲方程, 用非本地术语。 过度测算的测量数据是在域或其边界的一个子块上取得的时痕。 我们将显示线性地图从$\ kapapa 至用于回收的超版数据, 并在此基础上制定和分析牛顿型计划, 以有效恢复它。