The implementation of BIM methodologies for historical buildings presupposes not only the collection of data and information related to its geometric configuration and to the technical parameters of its constituent elements, but more generally the identification of those semantic values which make it part of the historical-cultural heritage shared in a specific context. It is therefore essential that the modelling objectives are explicitly defined in relation to the specific BIM uses required, in order to avoid risks of over-modelling. This paper proposes a process of geometric validation of building information models of high morphological complexity implemented through Scan-to-BIM procedures. By means of a controlled and interoperable workflow, a chain of software applications is defined that is able to determine the level of geometric accuracy (LOA) of the information model with respect to the numerical model derived from the point cloud. Two case studies of H-BIM modelling of historical monumental complexes dating back to the Romanesque period in Sardinia (Italy) are illustrated: the churches of Sant'Efisio a Nora (Cagliari) and Santa Maria del Regno (Sassari). In the discussion of the results, the need for a prior definition of modelling strategies in relation to the expected BIM uses is highlighted. The digital survey was carried out as a part of the research project titled, “The Romanesque and the territory. Construction materials of the Sardegna Giudicale”, and coordinated by prof. Stefano Columbu. The BIM model was developed by a students’ team as part of the teaching activities of the Architectural Drawing course at the School of Engineering, University of Florence. The imagines are extracted from the drawings of the students, Valeria Siddi, Elena Pastorelli, Liuba Gabrielli, Simone Riccio, Elisa Ricotti.
Publisher: Multidisciplinary Digital Publishing Institute
The application of protective coatings is an effective preventive strategy to avoid metal corrosion. Constant monitoring of the coating’s quality is fundamental for the successful preservation of the metallic objects by reducing their interaction with corroding agents. Their evaluation over time helps to identify failure at early stages and promote their removal and substitution. Several methods have been employed for coating evaluation (i.e., chemical analysis, thickness and homogeneity investigation). In this paper, we compare three methods—Optical Coherence Tomography (OCT), Confocal Raman Microspectroscopy (CRM), and Eddy Currents (ECs)—to evaluate thickness values and coating integrity. The results from the two optical techniques (CRM and OCT) agree, being able to detect the inhomogeneity of the layer on a micron scale but requiring correction to account for the refraction phenomenon. The Eddy Current is a fast and efficient method for thickness estimation, providing data with millimetric lateral resolution.
Abstract Infrared spectroscopy allows to reliably distinguish between calcites formed by different processes, e.g. geogenic and anthropogenic calcite. This approach can be used for rapid sample analysis in the radiocarbon dating of mortars. The datable component is represented by anthropogenic calcite, that results from the reaction of calcium hydroxide with the atmospheric CO2 during the hardening of the material. However, different possible sources of contamination can alter the true radiocarbon concentration and can thus make the mortar appearing either older or younger. The preventive identification of the origin of calcite present in the sample allows to measure only anthropogenic calcite, reducing the time and cost of Accelerator Mass Spectrometer (AMS) measurements. Many papers are present in the literature discussing the use of Fourier transform infrared spectrometry (FTIR) with the KBr pellet method, to distinguish the origin of calcite. In this paper, the use of attenuated total reflectance mode (ATR-FTIR) is evaluated since it may present valuable advantages such as non-destructivity, in the perspective of sample reuse for dating.
Jiamei Lin; Anders Svensson; Christine S. Hvidberg; Johannes Lohmann; Steffen Kristiansen; Dorthe Dahl-Jensen; Jørgen Peder Steffensen; Sune Olander Rasmussen; Eliza Cook; Helle Astrid Kjær; +8 more
Jiamei Lin; Anders Svensson; Christine S. Hvidberg; Johannes Lohmann; Steffen Kristiansen; Dorthe Dahl-Jensen; Jørgen Peder Steffensen; Sune Olander Rasmussen; Eliza Cook; Helle Astrid Kjær; Bo M. Vinther; Hubertus Fischer; Thomas Stocker; Michael Sigl; Matthias Bigler; Mirko Severi; Rita Traversi; Robert Mulvaney;
Countries: United Kingdom, Denmark, Italy, Switzerland, United Kingdom, Switzerland, Denmark
Large volcanic eruptions occurring in the last glacial period can be detected by their accompanying sulfuric acid deposition in continuous ice cores. Here we employ continuous sulfate and sulfur records from three Greenland and three Antarctic ice cores to estimate the emission strength, the frequency and the climatic forcing of large volcanic eruptions that occurred during the second half of the last glacial period and the early Holocene, 60–9 kyr before 2000 CE (b2k). Over most of the investigated interval the ice cores are synchronized, making it possible to distinguish large eruptions with a global sulfate distribution from eruptions detectable in one hemisphere only. Due to limited data resolution and large variability in the sulfate background signal, particularly in the Greenland glacial climate, we only list Greenland sulfate depositions larger than 20 kg km−2 and Antarctic sulfate depositions larger than 10 kg km−2. With those restrictions, we identify 1113 volcanic eruptions in Greenland and 737 eruptions in Antarctica within the 51 kyr period – for which the sulfate deposition of 85 eruptions is found at both poles (bipolar eruptions). Based on the ratio of Greenland and Antarctic sulfate deposition, we estimate the latitudinal band of the bipolar eruptions and assess their approximate climatic forcing based on established methods. A total of 25 of the identified bipolar eruptions are larger than any volcanic eruption occurring in the last 2500 years, and 69 eruptions are estimated to have larger sulfur emission strengths than the Tambora, Indonesia, eruption (1815 CE). Throughout the investigated period, the frequency of volcanic eruptions is rather constant and comparable to that of recent times. During the deglacial period (16–9 ka b2k), however, there is a notable increase in the frequency of volcanic events recorded in Greenland and an obvious increase in the fraction of very large eruptions. For Antarctica, the deglacial period cannot be distinguished from other periods. This confirms the suggestion that the isostatic unloading of the Northern Hemisphere (NH) ice sheets may be related to the enhanced NH volcanic activity. Our ice-core-based volcanic sulfate records provide the atmospheric sulfate burden and estimates of climate forcing for further research on climate impact and understanding the mechanism of the Earth system.
Publisher: Universität Hamburg, Hiob Ludolf Centre for Ethiopian and Eritrean Studies
Research for this article had the purpose of exploring medieval Armenian–Ethiopian connections. The investigations revealed three main contexts where Ethiopia and Ethiopians feature in the Armenian sources of the first millennium, without necessarily implying real-life encounters. Firstly, the earliest Armenian texts locate Ethiopia and discuss the genealogy of its people in line with the biblical account of the Diamerismos, as well as notions based on Eusebius of Caesarea’s Chronicle translated into Armenian from Syriac in the fifth century. Each author, then, interpreted this information according to his narrative needs or the purpose of a given composition. The discussion of these sources reveals the circulation of classical and Hellenistic notions on Ethiopia and the Ethiopians in Armenian, too, such as the confusion between Ethiopia, Arabia, and India, as well as anthropological or spiritual features attributed to Ethiopians already by classical authors. Secondly, the article analyses a series of calendrical treatises, starting with one authored by the seventh-century polymath Anania Širakac‘i, that passed on a short tale about a sixth-century gathering of scholars in Alexandria in order to determine the date of the Easter and establish tables for its calculation in the future. An Ethiopian wise man Abdiē was part of this international endeavour too, according to this tradition, and his presence marked Ethiopia as part of the eastern Mediterranean learned world, with its own cultural traditions. Armenian language hemerologia also preserved month names in Gǝʿǝz, reproduced in the Appendix. Thirdly, the article draws attention to a completely new way of viewing Ethiopia in ninth- to eleventh-century Armenian anti-dyophysite (antiByzantine) treatises where the Armenian Church and its doctrines or ritual practices were imagined as part of a vast, non-dyophysite orthodox world that included the Ethiopian Church. Intriguingly, this argumentative technique, formulated in terms that one may callanti-colonial ante litteram, may be traced among Coptic and Syriac polemicists as well, a subject of research that would benefit from further analysis.
The interest in high-resolution semantic 3D models of historical buildings continuously increased during the last decade, thanks to their utility in protection, conservation and restoration of cultural heritage sites. The current generation of surveying tools allows the quick collection of large and detailed amount of data: such data ensure accurate spatial representations of the buildings, but their employment in the creation of informative semantic 3D models is still a challenging task, and it currently still requires manual time-consuming intervention by expert operators. Hence, increasing the level of automation, for instance developing an automatic semantic segmentation procedure enabling machine scene understanding and comprehension, can represent a dramatic improvement in the overall processing procedure. In accordance with this observation, this paper aims at presenting a new workflow for the automatic semantic segmentation of 3D point clouds based on a multi-view approach. Two steps compose this workflow: first, neural network-based semantic segmentation is performed on building images. Then, image labelling is back-projected, through the use of masked images, on the 3D space by exploiting photogrammetry and dense image matching principles. The obtained results are quite promising, with a good performance in the image segmentation, and a remarkable potential in the 3D reconstruction procedure. International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, XLVI-2/W1-2022 ISSN:2194-9034 ISSN:1682-1777 ISSN:1682-1750
The theoretical presupposition of the discourse developed here is Benjamin’s conception of a dialectical image applied to the experience of the modern and contemporary city. The starting point is that of the radical strangeness between the inner life of the individual and the time of the modern metropolis. In this regard, we compare some verses taken from the third book of the Stundenbuch by Rainer Maria Rilke and Georg Simmel’s essay, Die Großstädte und das geistiges Leben, at the center of which is the Nervenleben as an intensification of the perceptive life typical of the experience of the modern city. We then move on to focus on the theme of the labyrinth analyzed by Benjamin in some passages of the Passagenwerk. In this regard, it is emphasized how the modern city realizes the ancient dream of the labyrinth elevating it to the sphere of language. The experience of the city as a labyrinth is interpreted as a «monotonous wandering», which is not delayed in a senseless roaming. In conclusion, the image of the Generic City and of the Junkspace theorized by Rem Koolhaas is compared, as an image that describes our present in the interweaving of the virtual city of cyberspace with the real city, as an alternative image to that of monad. As a monad, the image of the city still reserves the possibility of experiencing the truth, in a paradoxical gaze that captures the original idea of the city from the inside. This confirms that in the connection between city and monad already underlined by Leibniz “the true has no windows”, according to one of the most esoteric passages of the Passagenwerk.
This article analyses the representation of the pandemic in modern and contemporary literature, according to a thematological perspective. It aims to show the way in which the motives of guilt and destiny are inevitably mixed, through some declinations of the theme proposed by great writers ��� from Defoe to Camus, from Saramago to Philip Roth. LEA - Lingue e Letterature d'Oriente e d'Occidente, Vol. 10 (2021)
The paper intends to present the results of a multidisciplinary project concerning the architectural documentation and the three-dimensional virtualization of the Ramintoja Church in Vilnius (Lithuania), conducted through morphological-metric, diagnostic and archaeological analyses. The building, which is part of a baroque complex of Augustinian origin located in the historic center of Vilnius, has gone through multiple construction phases since its probable foundation around the XIV century. The study has provided initial historical-archival research and then it has been carried out a digital survey of the building through integrated methodologies. For this purpose, TLS have been combined with SfM photogrammetric methodologies through the acquisition of images both close-range and aerial by UAV. At the same time, archaeological studies have been carried out through the stratigraphic analysis of the masonry to determine the construction techniques adopted during the various historical phases. Finally, diagnostic analyses have been carried out through the analysis of the state of the instabilities in order to identify the main construction phases and the possible restoration and consolidation interventions. As part of a Lithuanian national project of dissemination and enhancement of Heritage, and on the basis of the results of researches, were then developed reconstructive hypotheses of the church by identifying the main historical periods, and creating for each, a 3D model. These have thus become the support for the creation of an interactive virtual tour, allowing, through Oculus visors, a VR experience for the knowledge and dissemination of the historical evolution of the architectural Heritage.DOI: https://doi.org/10.20365/disegnarecon.27.2021.13
Abstract Building prefabrication is facing the challenge to reduce the life-cycle impact of construction, enhance material circularity, and increase the quality of building products and processes. The paper presents the first phase of the research CARES - CArdboard RElocatable School developed with the Italian brand Archicart by Area S.r.l with the aim to prototype a temporary school unit. The work presented is focused on the industrialization of a prefabricated building technology based on the use of cardboard panels (PACOTECTM Stre-Wall panels). Cardboard is a circular and environmentally sustainable material but currently the design and manufacturing process lacks digital integration, resulting in poor quality control, limited adaptability, and lack of material optimization. To address sustainability goals, the work implemented a “file-to-factory” approach to redesign the design-manufacturing process of prefabricated cardboard panels, integrating industry 4.0 paradigms in manufacturing (automation, high-precision manufacturing) and the use of BIM tools for design to achieve better product-process quality and predictability. The redesigned workflow allows achieving sustainability goals, such as reduction of errors, reduction of material wastes, cost and time predictability, product customization, and adaptability. The workflow will be verified and tested in the design and manufacturing of prefabricated cardboard panels to build a temporary school unit.