Template:Standard linear wave scattering equations without body condition

[math]\displaystyle{ \Delta\phi=0, \, -h\lt z\lt 0,\,\,\,\mathbf{x} \in \Omega }[/math] [math]\displaystyle{ \frac{\partial\phi}{\partial z}=0, \, z=-h, }[/math] [math]\displaystyle{ \partial_n \phi = \alpha \phi,\,z=0,\,\,\mathbf{x} \in F, }[/math]