Intermediate equivalent source reconstructions q^t of the baffled circular piston in Figure 3b vibrating at f=1 kHz. The top row (a–f) shows estimates provided by TV after (a) t=1, (b) t=5, (c) t=10, (d) t=50, (e) t=100, and (f) t=500 iterations. The bottom row (g–l) shows estimates provided by the even layers of the VN, where (g) is the initial approximation q⁰ according to equation (31), and (l) is the final network output q¹⁰.