Second-generation surface wavelets can be an effective tool for compressing integral operator matrices arising from large-scale simulations of 3D problems. The author's approach generalizes previously reported results on wavelet-based operator compression to nonuniform grids and fairly general domains.

Kevin Amaratunga, "A Wavelet-Based Approach for Compressing Kernel Data in Large-Scale Simulations of 3D Integral Problems", Computing in Science & Engineering, vol. 2, no. , pp. 34-45, July/August 2000, doi:10.1109/5992.852389