Point scatterers Absorption and reflections 1 Acoustic impedance 1 Acoustic waveguides 1 Asymmetric scattering 1 Concrete specimens 1 Concretes 1 Crack detection 1 Damped oscillators 1 Discrete random media 1 Distributed cracking 1 Effective impedance 1 Elastic waves 1 Forward scattering 1 Frequency domain analysis 1 Inhomogeneous media 1 Numerical models 1 Oscillatory fields 1 Propagating waves 1 Subsurface cracks 1 Total reflection 1 Waveguides 1 Zero reflections 1 article 1 computer simulation 1 human tissue 1 theoretical study 1