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The 3D digital reproduction of panel paintings is an efficient practice through which to document their state of conservation thanks to the ability to study artwork both at the microscopic level, visualising the craquelure and the detachments of pictorial layers, and at the macroscopic level, analysing support structures and their deformations. In recent years, research has focused on new methodologies to handle multiple 3D scans acquired over time and to achieve data fusion to obtain multi-resolution products. In this paper, we present the results of the acquisition of the central panel of an earthquake-damaged triptych using two different 3D techniques (close-range photogrammetry and structured light) before and after its restoration to carry out a multi-temporal analysis of the conservation status and document the effects of the restoration. Furthermore, we performed laser scanning micro-profilometry on a small area of the painting to study the artist's technique and identify previous restorations. Finally, we merged the two 3D datasets (obtained by structured-light projection and micro-profilometry) to produce a multi-resolution 3D model with the aim of increasing the accuracy and readability of the final product. [ABSTRACT FROM AUTHOR]

The monitoring of the processes in the steel and metal industry calls for techniques that are capable of measuring the composition of metallic alloys at a distance and on moving [...]

A 'hybrid' method is proposed for the quantitative analysis of materials by LIBS, combining the precision of the calibration-free LIBS (CF-LIBS) algorithm with the quickness of artificial neural networks. The method allows the precise determination of the samples' composition even in the presence of relatively large laser fluctuations and matrix effects. To show the strength and robustness of this approach, a number of synthetic LIBS spectra of Cu-Ni binary alloys with different composition were computer-simulated, in correspondence of different plasma temperatures, electron number densities and ablated mass. The CF-LIBS/ANN approach here proposed demonstrated to be capable, after appropriate training, of 'learning' the basic physical relations between the experimentally measured line intensities and the plasma parameters. Because of that the composition of the sample can be correctly determined, as in CF-LIBS measurements, but in a much shorter time. [ABSTRACT FROM AUTHOR]

The ''Monetiere'' of Florence hosts the most important collection of Etruscan coins in the world. In the framework of the longstanding collaboration between the Monetiere and the Applied Laser and Spectroscopy Laboratory in Pisa, the Etruscan gold coin collection of the museum was studied. The measurements were performed at the Monetiere, using a portable energy-dispersive X-ray fluorescence (XRF) instrument. The quantitative determination of the gold alloys used for the realization of the coins was obtained applying the fundamental parameters method to the XRF spectra; as a result, using the self-organizing maps method, we were able to classify the coins in four main groups. The main parameter determining the classification is the quantity of silver in the alloy. The results obtained shed some light about the origin of the coins under study. [ABSTRACT FROM AUTHOR]