Interval analysis applied to dielectric spectroscopy: a guaranteed parameter estimation

Dielectric spectra of materials are often difficult to analyze since the common software algorithms and line shape functions do not always provide unambiguous data for the fitted parameters. In particular, this article deals with epoxy/ceramics nano-prepolymers studied by dielectric spectroscopy. In this situation, both system (the prepolymer with nanofillers) and method (the dielectric spectroscopy) are complex. Taking into account the experimental error of each data point in the measured dielectric spectrum, the sofware based on a global optimization algorithm which uses interval analysis, provides a confidence interval for every parameter of the dielectric function implemented in the software. Then, this software is able to deliver and guarantee the number of relaxation processes even if they are in part masked by other phenomena like conductivity or electrode polarization.