Influencing Factors in Acoustic Emission Detection: A Literature Review Focusing on Grain Angle and High/Low Tree Ring Density of Scots Pine

Among non-destructive testing (NDT) techniques applied to structural health monitoring in existing timber structures, ranging from visual inspection to more sophisticated analysis, acoustic emission (AE) is currently seldomly used to detect mechanical stresses in wooden building assets. This paper presents the results from a systematic literature review on AE NDT applied to monitor micro and macro fracture events in softwood, specifically Scots pine. This survey particularly investigates its application with respect to the tree rings density and grain angle inspection, as influencing factors well correlated with physical and mechanical characteristics of wood. The literature review was performed in a three-step process defined by the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) flow diagram, leading to the selection of 31 documents from different abstract and citation databases (Scopus, Web of Science and Google Scholar). The outcomes have highlighted how laboratory experiments, including several types of tests (tensile, cutting, compressive, etc.), were conducted in most cases, while a very limited number of studies investigated on in situ monitoring. In addition, theoretical approaches were often explored in parallel with the experimental one. It emerges that—for tree ring density studies—a multi-technique approach, which may include microscopic observations, could be more informative. Indeed, although not widely investigated, high/low tree ring density and grain angle were found as influencing factors on the AE parameters detected by the sensors, during condition and structural health monitoring experiments

Influencing Factors in Acoustic Emission Detection: A Literature Review Focusing on Grain Angle and High/Low Tree Ring Density of Scots Pine

Among non-destructive testing (NDT) techniques applied to structural health monitoring in existing timber structures, ranging from visual inspection to more sophisticated analysis, acoustic emission (AE) is currently seldomly used to detect mechanical stresses in wooden building assets. This paper presents the results from a systematic literature review on AE NDT applied to monitor micro and macro fracture events in softwood, specifically Scots pine. This survey particularly investigates its application with respect to the tree rings density and grain angle inspection, as influencing factors well correlated with physical and mechanical characteristics of wood. The literature review was performed in a three-step process defined by the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) flow diagram, leading to the selection of 31 documents from different abstract and citation databases (Scopus, Web of Science and Google Scholar). The outcomes have highlighted how laboratory experiments, including several types of tests (tensile, cutting, compressive, etc.), were conducted in most cases, while a very limited number of studies investigated on in situ monitoring. In addition, theoretical approaches were often explored in parallel with the experimental one. It emerges that—for tree ring density studies—a multi-technique approach, which may include microscopic observations, could be more informative. Indeed, although not widely investigated, high/low tree ring density and grain angle were found as influencing factors on the AE parameters detected by the sensors, during condition and structural health monitoring experiments

Conservation of species occupying ephemeral and patchy habitats in agricultural landscapes: The case of the Eurasian Reed Warbler

Habitat loss and fragmentation are amongst the main threats for animal populations. These two processes are mainly due to the conversion of natural habitats to agroecosystems and have effects at different spatial scales. The identification of their lands

Conservation of species occupying ephemeral and patchy habitats in agricultural landscapes: The case of the Eurasian reed warbler

Habitat loss and fragmentation are amongst the main threats for animal populations. These two processes are mainly due to the conversion of natural habitats to agroecosystems and have effects at different spatial scales. The identification of their landscape-scale effects is the first step to target habitat management toward specific actions. At the same time the role of single habitat patches should not be overlooked, since some processes, like habitat degradation, occur at the patch scale. Multi-scale studies allow evaluating the relative role of patch-scale versus landscape-scale factors on species distribution allowing the identification of the spatial scale toward which conservation and management actions should be targeted. We studied the distribution of the Eurasian reed warbler (Acrocephalus scirpaceus) in ephemeral reed beds embedded in an agricultural landscape. After separating the independent, landscape-scale effects of habitat loss and fragmentation per se, we evaluated the role of patch-scale characteristics. Our multi-scale analysis showed that landscape characteristics are the most important features, while the role of patch is weaker and varies depending on the landscape context. We found no effects of fragmentation per se and of habitat structure in single patches. Our results suggest that for some species adapted to live in naturally ephemeral and patchy habitats, landscape context could be more important than patch-scale factors. From a conservation point of view, for such species the management actions should be prioritized toward increasing landscape suitability rather than that of single habitat fragments

Nota sulla dimensione dei nidi e successo delle covate di Cannaiola (Acrocephalus scirpaceus) in fragmiteti del Litorale Romano (Italia Centrale)

We report some nesting and breeding parameters of the reed warbler in reedbeds patches. The nests were found only in pure reedbeds characterised by young stems, above or near water or on dry ground. In average, each nests was built on 3.06 Phragmites stems (± 1.06, range: 2-5, n = 16), at 1.31 m of height (0.31 ± , range from 0.70 to 2; n = 17). The average size of broods observed was determined to be 3.75 (± 0.75, range 2-5, n = 12). We observed 2.89 chicks (± 1.76, range 0-5, n = 9) in the 12 nests in which eggs were found

Conservation of species occupying ephemeral and patchy habitats in agricultural landscapes: the case of the Eurasian Reed Warbler

Habitat loss and fragmentation are amongst the main threats for animal populations. These two processes are mainly due to the conversion of natural habitats to agroecosystems and have effects at different spatial scales. The identification of their landscape-scale effects is the first step to target habitat management toward specific actions. At the same time the role of single habitat patches should not be overlooked, since some processes, like habitat degradation, occur at the patch scale. Multi-scale studies allow evaluating the relative role of patch-scale versus landscape-scale factors on species distribution allowing the identification of the spatial scale toward which conservation and management actions should be targeted. We studied the distribution of the Eurasian reed warbler (Acrocephalus scirpaceus) in ephemeral reed beds embedded in an agricultural landscape. After separating the independent, landscape-scale effects of habitat loss and fragmentation per se, we evaluated the role of patch-scale characteristics. Our multi-scale analysis showed that landscape characteristics are the most important features, while the role of patch is weaker and varies depending on the landscape context. We found no effects of fragmentation per se and of habitat structure in single patches. Our results suggest that for some species adapted to live in naturally ephemeral and patchy habitats, landscape context could be more important than patch-scale factors. From a conservation point of view, for such species the management actions should be prioritized toward increasing landscape suitability rather than that of single habitat fragments

Adoption of AI-Based Technologies in the Food Supplement Industry: An Italian Start-Up Case Study

Although many industries have already implemented technologies based on artificial intelligence (AI) in their business, the effects of new digital solutions on customer satisfaction are not yet fully known. This study aimed to evaluate the AI-based advice implemented by an Italian start-up operating in food supplements to support customer choices. The evaluation utilized the Delphi method and a questionnaire survey. This research aimed to provide companies wishing to use AI with a preliminary evaluation criterion for improving customer satisfaction through digital approaches. Research findings indicate that AI-based advice can improve customer perspectives, such as customer satisfaction and loyalty, by providing a value-added business service, diversified for each product category. However, some mistakes have emerged, which may still be a limitation in the use of AI-based advice. Therefore, this study presents an innovative approach to evaluate the performance of digital advice in traditional sectors such as the food industry

Effect of habitat amount, configuration and quality in fragmented landscapes

Landscape changes are driven by several factors, such as habitat loss, fragmentation and degradation. Untangling the independent contribution of each process is crucial, since effective conservation actions depend on the clear identification of the threatening process. Nevertheless in most landscape scale studies configuration metrics are often grouped together without further distinguishing between different habitat properties (e.g. subdivision vs scatteredness of habitat patches) furthermore few landscape scale studies have included measurements of habitat quality thus possibly overlooking important interactions with landscape structure. In order to tackle these issues we carried out a large scale field study following an experimental design that allowed us to disentangle the independent role of landscape processes. We chose the European reed warbler (Acrocephalus scirpaceus) as model species due to its ecological characteristics. Probability of the reed warbler presence increased in landscapes with increasing amounts of habitat and increased with the proportion of flooded reed bed patches in the landscape: variables related to the configuration of habitat, instead, did not play a relevant role in shaping distribution patterns. Results of the modelling inference revealed a crucial complementarity between habitat quality and landscape structure: regulation of the amount of water in the canals increased the habitat suitability of patches only for landscapes with intermediate amounts of habitat. (C) 2012 Elsevier Masson SAS. All rights reserved

Safe microclimate thresholds for photographic and cinematographic media: a new challenge in the era of climate change

Vulnerable collections such as photographic and cinematographic media can be preserved in historical buildings (which generally have poor thermal insulation, low moisture buffer, and energy demanding air conditioning systems) or in purpose-built spaces, which, differently, are more efficient. Regarding the vulnerable collections, we are focusing on films in cellulose nitrate and cellulose triacetate and on photographic media, in particular the paper prints. In general, storage in a frozen or cold environment for films is encouraged, because at lower temperature the kinetics of the chemical degradation reactions decreases. For paper prints we have to avoid the acidification of the paper support. According to the policy framework, we note heterogeneity and great variety of thresholds, but it is necessary that temperature must be lower than 15°C for films, and 20°C for paper prints. As for relative humidity the maximum suggested RH is 50% for both films and paper prints. It is very important to follow guidelines that improve the energy performance of the building, because this also allows for greater conservation of the cultural heritage preserved internally. The EN 16883:2017 concerns historical buildings and focuses the attention on the climate changes which can have an effect on hygrothermal and load risks. It is necessary to reduce the energy demand, reduce greenhouse gas emissions, and maintain indoor conditions suitable for collections

Acetic acid and cellulose acetate films: artificial ageing and preliminary risk assessment of climate-induced impact

Most cellulose acetate film archives are affected by the vinegar syndrome (Bigourdan, et al., 2000). This spontaneous and self-catalytic process leads to a rapid (i.e., in a few years) deterioration of film materials, which rate increases under unfavourable thermo-hygrometric storage conditions. Therefore, the actual problem facing archives is the preservation of collections that are not yet in acetic syndrome (or in its early stage), since films in advanced stages of decay are unrecoverable and can only be handled and digitised before their definite loss. This paper presents a study in laboratory in which the ageing of films in real storages has been reproduced in a climate chamber under different conditions of temperature (T), relative humidity (RH), and acetic acid concentration. Some laboratory tests have been conducted to investigate the state of conservation and deterioration before and after different ageing experiments. Subsequently, specific dose response functions (Fenech, et al., 2013) (Menart, et al., 2014) related to archival materials have been exploited for assessing the climate-induced risk predicted specifically for cellulose acetate films in an acetic acid polluted environment. Selected samples of virgin cellulose acetate films were artificially aged in a climate chamber (i.e., with constant RH and variable T) with known concentrations of acetic acid (i.e., order of magnitude 101, 102, 103, 104 parts per billion). To qualitatively detect the presence of gaseous acidic compounds, Acid Detection (A-D) strips (developed and produced by the Image Permanence Institute - IPI) were used. Then, the state of conservation of the materials before and after the different ageing experiments was evaluated by means of non-destructive UV-visible spectrophotometry and contact surface pH measurement coupled with Fourier Transform InfraRed spectroscopy (FTIR), in order to quantify the degree of (de)polymerization of the cellulose. The impact of different acetic acid concentrations under variable thermo-hygrometric conditions was estimated. The change in colorimetric features of the cellulose acetate films was measured by UV-visible spectrophotometry, while the chemical degradation was obtained in terms of the acidification (pH) of the material associated with the appearance of characteristic peaks of aldehyde and ketone compounds in the FTIR spectra as a consequence of cellulose hydrolysis. The results are expressed in terms of the retention percentage of the capacity to handle and display the film after artificial ageing. The life expectancy calculation method was deduced from existing dose-response functions applied to the experimental data obtained. These data reproduce real archival conditions, in which films in excellent condition and films suffering acetic syndrome (i.e., contaminating the surrounding atmosphere with acetic acid) are stored in the same space. Therefore, the research outcomes are useful for estimating life expectancy of cellulose acetate films in real case studies. References - Bigourdan J.L., Reilly J.M., Effectiveness of storage conditions in controlling the vinegar syndrome: preservation strategies for acetate base motion-picture film collections, in: Aubert M., & Billeaud R., Proceedings of the 5th Joint Technical Symposium - JTS, Paris (2000) 14-34. - Fenech A., Dillon C., Ntanos K., Bell N., Barrett M., Strlič M., Modelling the Lifetime of Colour Photographs in Archival Collections, Studies in Conservation, 58(2) (2013) 107-116. - Menart E., de Bruin G., Strlič M., Effects of NO2 and acetic acid on the stability of historic paper, Cellulose, 21(5) (2014) 3701-3713