-3\sqrt{\left(\frac{\textbf{H}^x_{ij}}{I_{x}}\right)^{2}+ \left(\frac{\textbf{H}^y_{ij}}{I_{y}}\right)^{2}+ \left(\frac{\textbf{H}^z_{ij}}{I_{z}}\right)^{2}}\right)}.
(smoothness-constrained) inversion with fixed regularization (most natural). A direct current (DC) one-dimensional (1D) VES (vertical electric sounding) modelling operator is used to generate data, ...