Before revision: Desing principles Since the whole idea of the model is to tailor a function to experimental data, the authors have defined a certain group of features as desirable, even if not essential, among those: smoothness of the surface; possibility of changing the shape and thus the interpolation on a broad class of experimental data for different materials; possibility to represent known criteria with limit set of parameters; convexity of the surface.
After revision: Design principles Since the whole idea of the model is to tailor a function to experimental data, the authors have defined a certain group of features as desirable, even if not essential, among those: smoothness of the surface; possibility of changing the shape and thus the interpolation on a broad class of experimental data for different materials; possibility to represent known criteria with limit set of parameters; convexity of the surface.