Full waveform inversion (FWI) is inherently an ill-posed inverse problem. Gradient preconditioning in FWI is crucial for improving the convergence and stability of the inversion process, as it helps ...

Thus, approximate dynamic programming (ADP) could be used to estimate value functions (Lyapunov functions) instead of SOS. Through backstepping technique, the control Lyapunov function (CLF) of the ...