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The handwritten signature is a biometric method used to verify a person's identity. This study lies within the scope of an online handwritten signature verification system, in which a signature is modelled by an analytical approach based on the empirical mode decomposition. The organised system is tested on the SVC2004 task1 and MYCT-100 databases. The implemented evaluation protocol shows the importance of the adopted method and allows obtaining an equal error rate of 1.83 and 2.23% for the SVC2004 task1 and the MYCT-100 databases, respectively.

Nanocrystalline binary powders Fe 90 Sb 10 (wt.%) have been elaborated by high energy ball milling in order to study the effect of the milling time on the microstructural and magnetic properties of these alloys. The evolution of structural, morphological and magnetic properties were investigated, as a function of milling time, using the X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-ray spectrometry (EDX) and the vibrating sample magnetometer (VSM). A disordered Fe (Sb) solid solution with body centered cubic (bcc) crystal structure is formed after twelve hours of milling from XRD results. When the milling time increases, the lattice parameter progressively increases from 0.2861 nm for the Fe 90 Sb 10 (zero hour milling) compound down to 0.2870 nm for thirty six hours of milling. The sample with the longest milling time has exhibited the lowest value for the mean grain size of 18.16 nm as well as the microstrain of 0.19%. Grain morphology of the powders at different formation stages was examined using scanning electron microscopy (SEM). The chemical composition homogeneity the powder form Fe 90 Sb 10 (wt.%) were studied done with EDX experiments. For Fe-10Sb (wt.%) nanostructured powders, magnetisation saturation ,coercive elds and remnant magnetisation derived from the hysteresis curves were discussed as a function of milling time.

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The mechanical alloying process has been used to synthesise the nanocrystalline Fe60Al35Mg5 ( wt % )powders in a high energy planetary ball-mill Retsch PM 400. The evolution structural, microstructural, morphological and magnetic properties of ball-milled powders at different milling times (t variation from 0 to 32 h) were investigated by X-ray diffraction using the MAUD program which is based on the Rietveld method, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX) and the vibrating sample magnetometer (VSM). The XRD results reveal the formation of a bcc-Fe (Al, Mg) solid solution after 8 h of milling possessing a lattice parameter of 0,2895nm after 32 h of milling. It is also observed a refinement of the grain size which reaches 18,75 nm, and an increase in the microstrain after 32 hours of milling. Morphological evolution of the powder particles of the preceding mixture with the increase of the milling time, shows the coexistence of larger and fine particles at the beginning of the milling process linked to the competition of the phenomena of fractures and welding. A more or less homogeneous distribution of the particle shape is observed after 32 hours of milling. The elemental maps of Fe , Al and Mg done with EDX experiments confirmed the results found by XRD about the evolution of the alloy formation. Magnetic measurements of the milled Fe60Al35Mg5 ( wt % ) powder mixture exhibit a soft ferromagnetic character where the magnetic parameters are found to be very sensitive to the milling time mainly due to the particle size refinement as well as the formation of the solid solutions. After 32 hours of milling, the evolution of the saturation magnetisation (MS), coercive field (HC) remanent magnetisation (Mr) and squareness ratio (Mr/Ms) derived from the hysteresis curves are discussed as a function of milling time.