Architectural Terracruda Sculptures of the Silk Roads: New Conservation Insights Through a Diagnostic Approach Based on Non-Destructive X-ray Micro-Computed Tomography
TL;DR: The results of the study of a fragment of architectural terracruda sculpture from the Buddhist archaeological site of Tepe Narenj (Kabul, Afghanistan, fifth-ninth centuries CE) are presented in this article.
Abstract: This work presents the results of the study of a fragment of architectural terracruda sculpture from the Buddhist archaeological site of Tepe Narenj (Kabul, Afghanistan, fifth-ninth centuries CE) t...
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TL;DR: Ferraro et al. as mentioned in this paper proposed a model for information engineering, electronics and telecommunications at the University of Calabria in Italy, using the STAR infrastructure, which is based on the idea of information theory.
Abstract: 1Department of Information Engineering, Electronics and Telecommunications, Sapienza University of Rome, Via Eudossiana 18, 00184 Rome, Italy 2Physics Department and STAR infrastructure, University of Calabria, I-87036 Arcavacata di Rende, CS, Italy 3Department of Information Engineering, University of Brescia, Via Branze 38, 25123 Brescia, Italy 4Université de Limoges, XLIM, UMR CNRS 7252, 123 Avenue A. Thomas, 87060 Limoges, France 5Institute of Automation and Electrometry, SB RAS, Novosibirsk 630090, Russia 6Novosibirsk State University, Pirogova 1, Novosibirsk 630090, Russia †These authors have contributed equally *Corresponding author: mario.ferraro@uniroma1.it
11 citations
28 Jun 2022
TL;DR: In this article , the authors exploit X-ray absorption as a nondestructive technique for the characterization of optical glass fibers, and obtain information about the spatial correlation of the refractive index at optical frequencies.
Abstract: : In spite of their ubiquitous applications, the characterization of glass fibers by means of all-optical techniques is still facing some limitations. Recently, X-ray absorption has been proposed as a method for visualizing the inner structure of both standard and microstructure optical fibers. Here, we exploit X-ray absorption as nondestructive technique for the characterization of optical glass fibers. Starting from absorption contrast X-ray computed micro-tomography measurements, we obtain information about the spatial profile of the fiber refractive index at optical frequencies. We confirm the validity of our approach by comparing its results with complementary characterization techniques, based on electron spectroscopy or multiphoton microscopy. Publishing Group under the terms of the Optica Publishing Group Publishing Agreement
2 citations
TL;DR: In this paper , the porosity of 3D printed parts has been subjected to porosity characterization by using experimental tests on dogbone samples subjected to plastic deformation, where multiple loading-unloading steps have been carried out and at the end of each step, the X-ray computed micro-tomography (μ-CT) has been employed for the identification of fabrication defects and for analyzing the crack growth mechanism that occurs after quasi-static loading tests.
Abstract: 3D printing is a widespread technology in different fields, such as medicine, construction, ergonomics, and the transportation industry. Its diffusion is related to the ability of this technique to produce complex parts without needing for assembly of different components or post-processing. However, the quality of the parts produced by additive manufacturing could be affected by the fabrication process, thus leading to the development of different kinds of defects such as porosity or inclusions. Understanding the role played by these defects and promoting strategies that could help reduce their occurrence represents a key point to allow using 3D printing for structural applications. In this work, 3D printed parts have been subjected to porosity characterization by using experimental tests on dogbone samples subjected to plastic deformation. In particular, multiple loading-unloading steps have been carried out and, at the end of each step, the X-ray computed micro-tomography (μ-CT) has been employed for the identification of fabrication defects and for analyzing the crack growth mechanism that occurs after quasi-static loading tests. Sample analysis reveals the presence of a high porosity that could be attributed to the fabrication process. After the sample’s plastic deformation, it was found an increase in both porosity percentage and pore dimensions. Moreover, the crack propagation mechanism is affected by porosity.
1 citations
TL;DR: In this article , the authors studied a key upland section and several profiles on the slopes and lowlands of the Tlaxcala Block, assuming that the topographic variability of the soil-sedimentary mantle contains the complete record of the landscape history.
1 citations
12 Sep 2022
TL;DR: In this paper , 3D printed parts have been subjected to porosity characterization by using experimental tests on Dogbones samples subjected to plastic deformation and X-ray computed micro-tomography (μ-CT) has been employed as an investigation tool for the identification of fabrication defects and for analyzing the crack growth mechanism that occurs after subjecting samples to quasi-static loading conditions.
Abstract: Abstract 3D printing is a widespread technology in different fields, such as medicine, construction, ergonomics, and the transportation industry. Its diffusion is related to the ability of this technique to produce complex parts without needing for assembly of different components or post-processing. However, the quality of the parts produced by additive manufacturing could be affected by the fabrication process, thus leading to the development of different kinds of defects such as porosity or inclusions. Understanding the role played by these defects and promoting strategies that could help reduce their occurrence represents a key point to allow using 3D printing for structural applications. In this work, 3D printed parts have been subjected to porosity characterization by using experimental tests on Dogbones samples subjected to plastic deformation. In particular, X-ray computed micro-tomography (μ-CT) has been employed as an investigation tool for the identification of fabrication defects and for analyzing the crack growth mechanism that occurs after subjecting samples to quasi-static loading conditions.
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TL;DR: Fiji is a distribution of the popular open-source software ImageJ focused on biological-image analysis that facilitates the transformation of new algorithms into ImageJ plugins that can be shared with end users through an integrated update system.
Abstract: Fiji is a distribution of the popular open-source software ImageJ focused on biological-image analysis. Fiji uses modern software engineering practices to combine powerful software libraries with a broad range of scripting languages to enable rapid prototyping of image-processing algorithms. Fiji facilitates the transformation of new algorithms into ImageJ plugins that can be shared with end users through an integrated update system. We propose Fiji as a platform for productive collaboration between computer science and biology research communities.
43,540 citations
"Architectural Terracruda Sculptures..." refers methods in this paper
...The ‘3D ImageJ Suite’ (Ollion et al. 2013) of the Fiji software library was applied to evaluate the density of the different components, which provides their volumetric fraction within the sample....
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...Image analysis was performed with Fiji (Schindelin et al. 2012), an open source image processing package based on ImageJ....
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...The volume of different components was obtained via the ‘3D Geometrical measurements’ and ‘3D Object Counter’ (Bolte and Cordelières 2007), plugins of Fiji....
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37,017 citations
"Architectural Terracruda Sculptures..." refers methods in this paper
...The VOI was filtered with a ‘3D Gaussian-Blur filter’ (Ollion et al. 2013) to reduce the image noise and segmented by an automatic thresholding algorithm (Otsu 1979) to separate the different materials in the sample (clay, sand, and voids)....
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Journal Article•
TL;DR: In this article, a convolution-backprojection formula is deduced for direct reconstruction of a three-dimensional density function from a set of two-dimensional projections, which has useful properties, including errors that are relatively small in many practical instances and a form that leads to convenient computation.
Abstract: A convolution-backprojection formula is deduced for direct reconstruction of a three-dimensional density function from a set of two-dimensional projections. The formula is approximate but has useful properties, including errors that are relatively small in many practical instances and a form that leads to convenient computation. It reduces to the standard fan-beam formula in the plane that is perpendicular to the axis of rotation and contains the point source. The algorithm is applied to a mathematical phantom as an example of its performance.
5,356 citations
"Architectural Terracruda Sculptures..." refers methods in this paper
...Axial slices were reconstructed with an isotropic voxel size of 20 μm using the FDK algorithm for cone-beam geometry....
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...In our case, since the micro-CT apparatus uses an X-ray cone beam source, the 3D digital reconstruction is performed using the algorithm by Feldkamp, Davis, and Kress (FDK) (Feldkamp, Davis, and Kress 1984)....
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TL;DR: In this article, a convolution-backprojection formula is deduced for direct reconstruction of a three-dimensional density function from a set of two-dimensional projections, which has useful properties, including errors that are relatively small in many practical instances and a form that leads to convenient computation.
Abstract: A convolution-backprojection formula is deduced for direct reconstruction of a three-dimensional density function from a set of two-dimensional projections. The formula is approximate but has useful properties, including errors that are relatively small in many practical instances and a form that leads to convenient computation. It reduces to the standard fan-beam formula in the plane that is perpendicular to the axis of rotation and contains the point source. The algorithm is applied to a mathematical phantom as an example of its performance.
5,329 citations
TL;DR: A novel toolbox for subcellular colocalization analysis under ImageJ is created that integrates current global statistic methods and a novel object‐based approach to assess proteins residing on intracellular structures by fluorescence microscopy.
Abstract: Summary It is generally accepted that the functional compartmentalization of eukaryotic cells is reflected by the differential occurrence of proteins in their compartments. The location and physiological function of a protein are closely related; local information of a protein is thus crucial to understanding its role in biological processes. The visualization of proteins residing on intracellular structures by fluorescence microscopy has become a routine approach in cell biology and is increasingly used to assess their colocalization with well-characterized markers. However, imageanalysis methods for colocalization studies are a field of contention and enigma. We have therefore undertaken to review the most currently used colocalization analysis methods, introducing the basic optical concepts important for image acquisition and subsequent analysis. We provide a summary of practical tips for image acquisition and treatment that should precede proper colocalization analysis. Furthermore, we discuss the application and feasibility of colocalization tools for various biological colocalization situations and discuss their respective strengths and weaknesses. We have created a novel toolbox for subcellular colocalization analysis under Image J, named JACoP, that integrates current global statistic methods and a novel object-based approach.
4,195 citations