1,720,994 research outputs found
Heat, temperature and energy: a formative experiment-based module including the use of infrared cameras
No full textThe historical development of the concept of energy can be brought back to the early studies of heat, suggesting that a unified treatment of heat, temperature and energy can be a possible route for teaching these complex subjects altogether. Here we present an experiment-based module centered on heat and temperature and on their relation with energy which was proposed to a class of prospective primary school teachers. The intervention redesigns a previously developed approach to include the concept of energy and use of infrared cameras. Learning outcomes are investigated through pre- / post-assessment questions, worksheets and final interviews
Un progetto, uno spazio, una prospettiva. Indagine riflettografica della Pala Bottigella di Vincenzo Foppa
No full textL'indagine riflettografica della Pala Bottigella, unitamente a quella radiografica, permette di chiarire alcuni aspetti particolarmente importanti delle modalità esecutive adottate da Foppa durante l'esecuzione della Pala Bottigella. Si ha conferma, tra l'altro, della presenza del Beato Domenico e della Beata Sibilla Biscossi fin dal primo momento della progettazione dell'opera
Can we unlock more information from interferometric sensors? Feasibility and performance analysis
No full textThe surface is the most representative part of an artwork and it is also the part most exposed to alterations due to interaction with the surrounding environment. Non-destructive surface monitoring is of crucial importance in preserving and conserving cultural heritage and optical interferometric techniques allow to acquire the surface structure down to the submicrometric scale. In this work, we start from laser microprofilometry based on conoscopic holography sensors to unlock a new way of measuring the surface. In the last years, this technique has proven effective for surface diagnostic in heritage science providing high-quality surface dataset on diffusive, highly reflective, and polychrome artworks. However, an open problem in profilometry is the spatial referencing of surface topography at the micrometer scale, due to the lack of references in the height data with respect to the visually readable surface. We have recently developed a solution that exploits the raw intensity signal collected by the single-point sensor (i.e. the backscattered signal of the laser diode) and the interferometric height dataset, which are intrinsically registered. This method provides additional information about material texture, color variations or artist's marks that enable spatial registration and data fusion tasks, otherwise difficult in traditional laser profilometry. In this paper we analyzed the feasibility and the performance of the whole process chain from the acquisition to the exploitation of the dual height-intensity datasets, focusing the attention on the raw intensity signal interpreted as a "raw reflectance signal". We demonstrate the effectiveness of the proposed approach by presenting results on exemplary case studies
Integrated microprofilometry and multispectral imaging for full-field analysis of ancient manuscripts
Full text linkA novel workflow is proposed to combine the use of two powerful techniques in the study of ancient manuscripts: multispectral imaging and optical microprofilometry. Multispectral imaging is routinely used and allows to examine each individual folium as a superposition of layers that give different responses in the UV-Vis-NIR bands. It enables the analysis of the conservation state of an object, the mapping of previous restorations or the detection of writings no longer visible. The downside of this technique is the lack of quantitative data on surface morphology. On the other hand, surface microprofilometry on book heritage is unexplored. The optical scanning microprofilometer used in this work employs single-point, interferometric depth-sensors that enable to measure the surface topography of the manuscript (deformation and roughness) in full-field (areas of tens of centimeters) at micrometer scale. The crucial task of spatial referencing the surface topography at micrometer scale to the visible features (e.g., written text) is performed with a novel procedure that solves the problem of the lack of reference points in the microprofilometer height data. We exploit the raw intensity signal collected by the laser depth sensor to fuse the interferometric measurements with the multispectral image stack. The full-field integration of quantitative microsurface measurements and in-band imaging responses enables a more comprehensive exploration of ancient manuscripts, by integrating materials-surface analysis, advancing the diagnostic protocol
Archaeometry of air pollution: Urban emission in Italy during the 17th century
No full textPast sources of air pollution in the cities of Northern Italy are investigated by a critical analysis of a 17th-century treatise written by B.Ramazzini, a medical doctor interested in the associations between work, environmental pollution and health. In this paper, past emissions due to domestic and craftsman's activity have been recognised and classified according to the potential damage to cultural heritage. The indoor environment experienced concentrations of smoke due to bad ventilation and domestic combustion for lighting and heating. High indoor concentrations of sulphur dioxide were common from the burning of sulphur for domestic and workshop activities. The outdoor environment experienced smoke for the combustion necessary for several workshop activities and uncontrolled dangerous emission. The urban pollution was not homogeneous; the craftsmen's activities were organised in different specific areas so that the environmental deterioration potentials changed form site to site inside the same town
Focus-stacking system for 3D acquisition of sculptures and archaeological manufacts
Full text linkIn this paper we present the basic features of the Shape from Focus techniques and discuss the potentiality of its application in the 3D imaging of small sculptures and archaeological manufacts. A scanning system for optimizing the image stack acquisition in laboratory was assembled, while 3D reconstruction was done in ImageJ
Optical surface metrology for heritage science: proof of concept and critical-constructive discussion
No full textIn the engineering field, surface metrology is a valuable tool codified by international standards that enables the quantitative study of small-scale (down to micrometer) surface features, i.e., the surface topography. However, it is not recognized as a resource in heritage science. In literature we find a large use of qualitative inspection of surface morphology or of single-parameter roughness analysis, which confirms the need and potential of such diagnostics. Reasons of the gap are variegate; artworks are hand-made peculiar targets with heterogeneous surfaces, a multiscale approach is necessary, lack of guidelines and unclear meaning of surface roughness descriptors. We propose a critical-constructive discussion through Proof-of-Concept (POC) applications, on the use of surface metrology based on ISO descriptors. Exemplary case studies include: 1) In situ and in-process monitoring of painting microtexture in a Venetian masterpiece: wide and in-band roughness analysis is performed through the complementary use of amplitude, spatial, and hybrid parameters. 2) Multiscale roughness analysis for treatment monitoring in highly reflective metal artworks, requiring high micrometer accuracy in both depth (0.1 mu m and lateral (5 mu m) directions: surface analysis is performed on scale-limited components to discriminate different surface processes. Surface data are acquired using a prototype of a laser scanning profilometer based on conoscopic holography, with a versatile setup and a surface data pipeline tailored to artwork applications
Metaphors and analogies proposed by perspective primary teachers to support the exploration of magnetic phenomena
Full text linkAnalogies and Metaphors play an important role in primary science education to correlate abstract aspects and lived experiences, providing concrete meanings for pupils. They represent important educational tools that can help young pupils to approach towards abstract physics concepts like those related to magnetic phenomena. In order to improve the competencies of Prospective Primary Teacher (PPT) students related to the use of analogies and metaphors in education, a specific module of formative intervention was developed and propose
Thermal Quasi-Reflectography: a new imaging tool in art conservation
No full text"\"In the artwork conservation field, non contact diagnostic and imaging methods are widely used and most welcomed. In this work a new imaging tool, called Thermal Quasi-Reflectography (TQR), is proposed and demonstrated. It is based on the recording, by suitable procedures, of reflected infrared radiation in the MWIR band (3-5 μm). The technique, simple to perform, can provide very interesting results in the analysis of the painting surfaces. TQR was demonstrated in situ on two famous artworks: the Zavattari’s frescos in the Chapel of Theodelinda (Italy) and the masterpiece by Piero della Francesca “The Resurrection” (Italy).\"
Beyond the youth smile: Investigating techniques and materials in Caroto's paintings by analytical single-point analyses and IR reflectography in full-field
Full text linkGiovan Francesco Caroto was a famous Renaissance who played a fundamental role in Venetian painting at the turn of the 15th and 16th centuries. Despite this, just a few of his works have been studied in depth with a multidisciplinary approach between art history and scientific diagnostics. In this study, twenty paintings spanning almost forty years of his entire production in different areas of Northern Italy were analysed. The occasion for this study was the monographic exhibition dedicated to Caroto in Verona, in the halls of the Palazzo della Gran Guardia, in 2022. The research project focused on the application of non-invasive and in-situ techniques on a large number of paintings, following a consolidated protocol from imaging to spectroscopic analyses. The goal was to transition the local determination into a whole pattern analysis through a chemometric statistical evaluation. Indeed, it was possible to gain an overview of the material dimension of the artist by correlating chemical data with the year and place of production. This was achieved by overlapping Vis-IR imaging data with a high number of surface analyses (UV-Vis-NIR fibre optics reflectance spectroscopy -FORS-), and stratigraphic elemental analyses (XRF spectrometry). A multi-layer reading of the analysed works was proposed from the preparatory layer to the glaze and surface finish. Full-field IR reflectography allowed the corpus analysed to be considered in its entirety, discriminating original materials and retouchings, for the identification of the areas most representative for chemical analyses. The application of this protocol, along with the cross-discussion of the data acquired, and the comparison with historical sources enabled the identification of the artist's palette and its evolution over time. Moreover, the determination of minerals and minor elements in pigments traced Caroto's movements between Verona and Casale Monferrato, also providing information on material supply habits
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