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The development of innovative applications of imaging technologies for monitoring change in cultural heritage objects is central to the CHANGE-ITN project. Within this framework, the authors' ongoing work targets the harnessing of hyperspectral imaging (HSI) for the documentation of cleaning treatments on the monumental University of Oslo Aula unvarnished oil paintings on canvas (1909–1916) by Edvard Munch (1863–1944). This is applicable to unvarnished paint surfaces in general. Particularly, this paper evaluates HSI techniques for the investigation of cleaning tests carried out in 2008, which targeted the removal of visible, ingrained particulate matter from Munch's unvarnished oil paints and exposed grounds on Kjemi (1914–1916). An exploratory in situ HSI campaign using visible to near-infrared (VNIR) and short-wave infrared (SWIR) cameras was undertaken to capture the soiled or previously cleaned areas on the painting's surface, with comparisons to analogous mock-ups. Principal component analysis (PCA) was used to extract information about possible trends with respect to the soiling. Results indicate that in both VNIR and SWIR ranges, the intensity of reflectance can be used to discriminate statistically between soiled and unsoiled/cleaned areas, whereas in SWIR, combination and first overtone bands of oil peaks can also serve as markers. [ABSTRACT FROM AUTHOR]

This paper describes a cleaning method for removing ingrained carbonaceous dirt from lime-based wall paintings by utilizing hydrogels in combination with aqueous cleaning liquids. Nanorestore Gel® Peggy 6 has a number of advantages over traditional cleaning methods, and it is capable of holding large amounts of liquid, but it limits liquid penetration into the substrate. Cleaning action occurs only at the interface, without affecting the surrounding area or leaving residues. Furthermore, its viscosity makes it an ideal tool for treating irregular, vaulted surfaces. Laboratory experiments conducted on limewashed model tiles were decisive in the design of in situ experiments on fifteenth-century wall paintings. The cleaning efficiency of each method was assessed and quantified using colorimetry, 2-D FTIR mapping and image analysis using Cultural Heritage ImageJ. SEM-EDX was used for seeking residues. Results of both the model and in situ cleaning tests show a significant reduction of ingrained dirt when comparing Nanorestore Gel® Peggy 6 to traditional methods. Best visual results were obtained when cleaning with hydrogel loaded with 5% triammonium citrate was following by swabbing with a wet sponge. However, using water alone with the gel yielded almost as good a result in situ, making cleaning possible without any risk of residues. [ABSTRACT FROM AUTHOR]

This paper portrays a neoteric methodology for quantifying surface cracks and shrinkage that appears in the soil after desiccation under certain atmospheric conditions using image analysis technique. Soils over a wide range of plasticity are prepared by mixing high plastic sodium bentonite with non-plastic fly ash. Cylindrical specimens with different thickness, initial moisture content and densities were prepared and allowed to desiccate at an average temperature of 25 °C and relative humidity of 40%. The ImageJ software is used for image processing and Matlab for quantification of surface cracks and shrinkage in the specimens. The effect of different parameters like plasticity of soil, sample thickness, and initial moisture content on surface cracks and shrinkage are expressed in terms of crack density factor (CDF) and crack intensity factor (CIF). The result shows that both CDF and CIF increase with an increase in the plasticity index of the soil and initial moisture content of the specimens. In contrast; with the increase in sample thickness, CDF decreases slightly whereas CIF increases. [ABSTRACT FROM AUTHOR]

This paper proposes a method for measuring the particle aggregation and homogeneity of mixtures by image analysis. The influence of threshold on estimating the level of aggregation is investigated. The number of pixels in a binary image is used to estimate the level of aggregation via a threshold value for the mixing patterns, which is a useful parameter for characterising the homogeneity. The mixing efficiency can be characterised by the evolution of the pixel aggregation. This method can be used to measure the particle aggregation of the mixture, and to obtain the mixing homogeneity that is most consistent with the results from box-counting methods that use erosions and Betti numbers. A simple model for evaluating the mixing effect is developed. This model exhibits a satisfactory agreement with experimental data. This method may be utilised to analyse a kind of particle aggregation in which motive components or tracers are visualised. [ABSTRACT FROM AUTHOR]

Discipline-based art education teaches children to understand a language of visual imagery in order to expand their expressive options when they use art materials. Putting magic literacy at the center of studio art instruction departs from traditional practice, which encourages media manipulation but which discourages systematic image manipulation. Children's tutored images display visual concepts (aesthetic properties) acquired as a result of instruction. A discipline-based art lesson has three components: visual analysis, art production, and critical/historical analysis. Consistency of visual concepts (interlocking images) throughout all three components constitutes systematic studio art instruction that introduces children both to media and to the dimensions of artistic imagery. [ABSTRACT FROM AUTHOR]