Search results for "paint"
showing 10 items of 605 documents
Petro-archaeology of Gallo-Roman lime mortar. Attempt to reconstruction and interpretation of the “chaînes opératoires”: from material to ancient cra…
2003
Petro-archaeological research on Gallo-Roman lime mortars is based on a simple analytical methodology: observations with optical microscopy in transmission, which brings us a maximum of data about the material and the various stages of the “chaîne opératoire”. This work enabled us to draw the general features of the craftmanship (common practices of the ancient structores and tectores), to establish the relations between mortar composition and its “primary” and “secondary” architectural function, then to perceive what are the markers and motivations of the formula adaptations. The importance of the geological environment is shown, because it induces economic and technical choices, requiring…
Improved chemometric approach for XRF data treatment: application to the reverse glass paintings from the Lipari collection
2023
The Aeolian cultural heritage preserves hundreds of testimonies of the past that have passed through six millennia of history. Among these, the Archeological Park of the Aeolian Islands with the Museum Luigi Bernab`o Brea (Italy) preserves a valuable set of artworks, which are related to a little-known ‘popular’ figurative heritage. It is an assemblage of small glass foils decorated using the technique of reverse painting, datable to between the end of the 17th century and the end of the 18th century, and actually under investigation by historians. Here, an X-ray fluorescence (XRF) spectroscopy study (performed with portable equipment) is combined with a multivariate approach that allows us…
Image inpainting using directional wavelet packets originating from polynomial splines
2020
The paper presents a new algorithm for the image inpainting problem. The algorithm is using a recently designed versatile library of quasi-analytic complex-valued wavelet packets (qWPs) which originate from polynomial splines of arbitrary orders. Tensor products of 1D qWPs provide a diversity of 2D qWPs oriented in multiple directions. For example, a set of the fourth-level qWPs comprises 62 different directions. The properties of the presented qWPs such as refined frequency resolution, directionality of waveforms with unlimited number of orientations, (anti-)symmetry of waveforms and windowed oscillating structure of waveforms with a variety of frequencies, make them efficient in image pro…
Agent assisted interactive algorithm for computationally demanding multiobjective optimization problems
2015
We generalize the applicability of interactive methods for solving computationally demanding, that is, time-consuming, multiobjective optimization problems. For this purpose we propose a new agent assisted interactive algorithm. It employs a computationally inexpensive surrogate problem and four different agents that intelligently update the surrogate based on the preferences specified by a decision maker. In this way, we decrease the waiting times imposed on the decision maker during the interactive solution process and at the same time decrease the amount of preference information expected from the decision maker. The agent assisted algorithm is not specific to any interactive method or s…
An examination of nonresponse in a study on daily family life: I do not have time to participate, but I can tell you something about our life
2012
The aim of this study was to look at the issue of nonresponse and self-selection bias in the context of a family study on daily family life. Data on the participating families and refusers were gathered as part of the wider Palette study in which questionnaires and diaries were used as data collection methods. On the basis of these data (N = 208 participating families and 119 refuser families), we profile the families left outside the study. The parents who declined to participate in the Palette study were asked to fill in a short refusal form, which included questions concerning their family background and reasons for refusal, and they were also asked to write freely about their everyday l…
La ceramica sovradipinta bizantina di Gortina
2008
EMMA VITALE (2008). La ceramica sovradipinta bizantina di Gortina. p. 1-304, PADOVA:Aldo Ausilio Editore in Padova-Bottega d''Erasmo, ISBN: 978-88-6125-071-0 The Byzantine painted pottery from the Gortys excavations represents a new class among the painted pottery productions which spread over the Mediterranean basin since the end of the 6th century AD. The first finds came to light around the mid-fifties during the excavations in the Temple of Athena on the acropolis (Haghios Ioannis hill), but the greatest number of fragments comes from the upper town and, particularly, from the Byzantine quarter between the Pretorio and the Apollo Pythios temple: here, the finding of a ceramic factory si…
Laser fluence, repetition rate and pulse duration effects on paint ablation
2006
Abstract The efficiency (mm3/(J pulse)) of laser ablation of paint was investigated with nanosecond pulsed Nd:YAG lasers (λ = 532 nm) as a function of the following laser beam parameters: pulse repetition rate (1–10,000 Hz), laser fluence (0.1–5 J/cm2) and pulse duration (5 ns and 100 ns). In our study, the best ablation efficiency (η ≅ 0.3 mm3/J) was obtained with the highest repetition rate (10 kHz) at the fluence F = 1.5 J/cm2. This ablation efficiency can be associated with heat accumulation at high repetition rate, which leads to the ablation threshold decrease. Despite the low thermal diffusivity and the low optical absorption of the paint (thermal confinement regime), the ablation th…
“De la mà de un florentí” y “De mestre Marçal”. Los dibujos del pintor valenciano Joan Moreno (1382-1448) y el cuaderno de los Uffizi
2020
A partir de la localización del testamento, inventario de bienes y almonedas posteriores tras el fallecimiento del pintor Joan Moreno en la ciudad de Valencia en 1448, se analiza la importancia del dibujo en los talleres del gótico internacional. La mención específica de dibujos del alemán Marçal de Sas (†1410) y de un florentino que podría ser Gherardo Starnina (c. 1354-1409-13) ofrece la posibilidad de analizar esta documentación en relación con el cuaderno de dibujos de los Uffizi (inv. 2264F-2281F, 18304F-18306F, 18324). Un repertorio de dibujos que se considera realizado en torno a los años 1400 en la ciudad de Valencia y que responde precisamente a las dos corrientes más importantes s…
Perceived need to increase physical activity levels among adults at high risk of type 2 diabetes. A cross-sectional analysis within a community-based…
2012
Background. Increased physical activity is a cornerstone of type 2 diabetes prevention. The perception of a need to change is considered essential in behaviour change processes. However, the existing literature on individuals' perceived need to change health behaviour is limited. In order to improve understanding of diabetes prevention through increased physical activity levels (PAL), we assessed factors associated with perceiving a need to increase PAL among adults at high risk of diabetes. Methods. Opportunistic screening was used within a primary-care based lifestyle intervention covering 10 149 men and women at high risk of type 2 diabetes. Data were obtained at baseline visits. Th…
Consolidation tests on the graffiti of the Steri’s prison with nanotechnological Ca(OH)2 dispersed in iso-propanol
2009
The combination of weathering and human activities often induce pyhisicochemical alteration on the surface of wall paintings. One of the most still largely used restoration techniques for these works of art, is based on the application of organic polymers. Due to their ability to stick detached and powdered pigments,these products provide an immediate consolidating effects. Unfortunately, both their aging and their pyhisicochemical incompatibility with the inorganic support can have serious consequences also causing further damage to the work of art. In this paper a new technological approach is presented based on the use of Ca(OH)2 nanoparticles dispersed in isopropanol. Some applicative t…