This subject aims at developing new methods of X/gamma-ray spectrum analysis for the characterization of uranium-bearing ore, enabling to process data obtained in the framework of nuclear mining activities. This subject will be developped into two parts. The first part will concern the processing of complex gamma-ray spectra, obtained using different types of medium-resolution scintillators (such as NaI or LaBr3 detector). The main purpose of this part will be related to the processing of complex regions of interest using deconvolving methods by non-parametric Bayesian inference, notably by using the SINBAD code, initially developed by CEA LIST for the processing of HPGe spectra. The second part of the subject will concern the analysis of low-resolution spectra obtained using a NaI detector in order to obtain a spectrometric information. In this case, a traditional approach based on the analysis of photoelectric peaks is not conceivable. The problem will be studied in the form of an inverse problem using a model of the detector response and a reconstruction, using an approach analogous to computed tomography. The performances of different types of reconstruction algorithms will be studied (EM analysis, non-parametric Bayesian approach).