Proportions and Deformations in the Mosque‑Cathedral of Cordoba

This research presents a dimensional analysis of the arcades of one of the most emblematic spaces of the Mosque-Cathedral of Cordoba: its central nave, located besides the mihrab in the ambitious extension carried out by Al-Hakam II. In order to accomplish this survey, a digital model was created from the point cloud obtained with a 3D laser scanner. Subsequently, earlier theories of architectural proportions related to this monument have been reviewed. The comparison of these earlier drawings with the corresponding digital models allows the precision of their different hypotheses to be assessed. Architectonic deformations not considered by the scientific literature are also quantified here. Finally, this research indicates certain partial order relations close to the proportion 1.3, though it should be noted that not all the arcades share the same dimensions and thus no general theory applies to their proportions.CRUE-CSIC agreementSpringer Natur

The Mosque-Cathedral of Cordoba: Graphic Analysis of Interior Perspectives by Girault de Prangey around 1839

This research has been funded by internationalisation grants awarded to the Instituto Universitario de Arquitectura y Ciencias de la Construcción (IUACC) of the VI Plan Propio de Investigación y Transferencia of the University of Seville.This research has been made possible thanks to the collaboration of the Cabildo de la Catedral de Córdoba. The authors are also grateful for the support from the research group Expregrafica, Lugar Arquitectura y Dibujo (PAIDI-HUM-976); Programa de Doctorado en Arquitectura, Instituto Universitario de Arquitectura y Ciencias de la Construcción from the University of Seville; the research group Ingeniería Cartográfica (PAIDI-TEP-164) from the University of Jaén; and the Survey and Modelling Laboratory (SMlab) from the University of Granada.The work of Philibert Girault de Prangey, who was a draughtsman, pioneering photographer and an Islamic architecture scholar, has been the subject of recent exhibitions in his hometown (Langres, 2019), at the Metropolitan Museum (New York, 2019) and at the Musée d’Orsay (Paris, 2020). After visiting Andalusia between 1832 and 1833, Prangey completed the publication “Monuments arabes et moresques de Cordoue, Seville et Grenada” in 1839, based on his own drawings and measurements. For the first time, this research analyses his interior perspectives of the Mosque-Cathedral of Cordoba (Spain). The novel methodology is based on its comparison with a digital model derived from the point cloud captured by a 3D laser scanner. After locating the different viewpoints, the geometric precision and the elaboration process are analysed, taking into account historic images by various authors, other details published by Prangey and the architectural transformations of the building. In this way, the veracity and documentary interest of some beautiful perspectives of a monument inscribed on the World Heritage List by UNESCO is valued.Programa de Doctorado en Arquitectura, Instituto Universitario de Arquitectura y Ciencias de la Construccion from the University of Sevilleresearch group Ingenieria Cartografica from the University of Jaen PAIDI-TEP-164Survey and Modelling Laboratory (SMlab) from the University of GranadaResearch group Expregrafica, Lugar Arquitectura y Dibujo PAIDI-HUM-97

Quality specification and control of a point cloud from a TLS survey using ISO 19157 standard

This paper presents an application of the ISO 19157 framework to the case of a point cloud (PC) representing a heritage asset whose purpose is to serve specific use cases that could be managed in a building information modeling (BIM) environment. The main contribution of this study is to clarify the relationships between the different parts of the ISO 19157 framework applied to heritage building information modeling (HBIM) products derived from terrestrial laser scanner (TLS) surveys by means of a running example. This paper presents a proposal to evaluate, control and report on the quality of the TLS survey of the Ariza Bridge (a 16th century construction). In order to achieve this objective the data quality specifications that must be met are defined by describing and identifying the requirements of five use cases of the data product: 3D visualization, location transfer, measurement, plane generation and absolute positioning. The specifications, according to ISO 19157, are formalized by selecting the data quality element to be measured, its scope, the measure used and the level of conformity necessary for the element to be accepted. In addition, the control methods for each quality element are proposed.Junta de Andalucia PAIDI-TEP-164Universidad de Jae?n POAIUJA 21-22 Universidad de Jaen / CBUA Universidad de Jaen PAIDI-TEP-164 POAIUJA 21-22 TEP164_202

Comparison of Gridded DEMs by Buffering

This research was partially funded by the research project "Functional Quality in Digital Elevation Models in Engineering" (https://coello.ujaen.es/investigacion/web_giic/funquality4 dem/, accessed on 28 July 2021) of the State Research Agency. PID2019-106195RB-I00/AEI/10.13039/ 501100011033.Comparing two digital elevation models (DEMs), S1 (reference) and S2 (product), in order to get the S2 quality, has usually been performed on sampled points. However, it seems more natural, as we propose, comparing both DEMs using 2.5D surfaces: applying a buffer to S1 (single buffer method, SBM) or to both S1 and S2 (double buffer method, DBM). The SBM and DBM approaches have been used in lines accuracy assessment and, in this paper, we generalize them to a DEM surface, so that more area of the S2 surface (in the case of the SBM), or the area and volume (in the case of the DBM) that are involved, more similarly are S1 and S2. The results obtained show that across both methods, SBM recognizes the presence of outliers and vertical bias while DBM allows a richer and more complex analysis based on voxel intersection. Both methods facilitate creating observed distribution functions that eliminate the need for the hypothesis of normality on discrepancies and allow the application of quality control techniques based on proportions. We consider that the SBM is more suitable when the S1 accuracy is much greater than that of S2 and DBM is preferred when the accuracy of S1 and S2 are approximately equal.research project "Functional Quality in Digital Elevation Models in Engineering" of the State Research Agency PID2019-106195RB-I00/AEI/10.13039/50110001103

Deep learning methods applied to digital elevation models: state of the art

Deep Learning (DL) has a wide variety of applications in various thematic domains, including spatial information. Although with limitations, it is also starting to be considered in operations related to Digital Elevation Models (DEMs). This study aims to review the methods of DL applied in the field of altimetric spatial information in general, and DEMs in particular. Void Filling (VF), Super-Resolution (SR), landform classification and hydrography extraction are just some of the operations where traditional methods are being replaced by DL methods. Our review concludes that although these methods have great potential, there are aspects that need to be improved. More appropriate terrain information or algorithm parameterisation are some of the challenges that this methodology still needs to face.Functional Quality of Digital Elevation Models in Engineering’ of the State Agency Research of SpainPID2019-106195RB- I00/AEI/10.13039/50110001103

Digital Graphic Documentation and Architectural Heritage: Deformations in a 16th-Century Ceiling of the Pinelo Palace in Seville (Spain)

Suitable graphic documentation is essential to ascertain and conserve architectural heritage. For the first time, accurate digital images are provided of a 16th-century wooden ceiling, composed of geometric interlacing patterns, in the Pinelo Palace in Seville. Today, this ceiling suffers from significant deformation. Although there are many publications on the digital documentation of architectural heritage, no graphic studies on this type of deformed ceilings have been presented. This study starts by providing data on the palace history concerning the design of geometric interlacing patterns in carpentry according to the 1633 book by López de Arenas, and on the ceiling consolidation in the 20th century. Images were then obtained using two complementary procedures: from a 3D laser scanner, which offers metric data on deformations; and from photogrammetry, which facilitates the visualisation of details. In this way, this type of heritage is documented in an innovative graphic approach, which is essential for its conservation and/or restoration with scientific foundations and also to disseminate a reliable digital image of the most beautiful ceiling of this Renaissance palace in southern Europe.Instituto Universitario de Arquitectura y Ciencias de la Construcción (IUACC) of the VII Plan Propio de Investigación y Transferencia in the University of Sevill

Structured light in the digital reconstruction of architectural details

[EN] The interest in cataloguing historical heritage has involved the growing development of techniques of three-dimensional scanning in recent years. The present work introduces the technique of structured light as a digitalization method that despite its limitations provides a powerful tool for surveying architectural details. The results found with structured light in the architectural survey of the Hospital Real of the Universidad de Granada (Spain) have been satisfactory as a substitute or a complement to the laser scanner and digital photography.[ES] El interés en la catalogación del patrimonio histórico ha supuesto un creciente desarrollo de las técnicas de escaneado en tres dimensiones en los últimos años. En el presente trabajo se introduce la técnica de luz estructurada como un método de digitalización que, a pesar de sus limitaciones, es una potente herramienta para el levantamiento de detalles arquitectónicos. Los resultados obtenidos con la luz estructurada en el levantamiento arquitectónico del Hospital Real de la Universidad de Granada han sido satisfactorios como sustitutivo o complemento al escáner láser y la fotogrametría digital.León Robles, C.; Reinoso Gordo, JF.; Mataix Sanjuán, J. (2018). Luz estructurada en la reconstrucción digital de detalles arquitectónicos. EGA. Revista de Expresión Gráfica Arquitectónica. 23(32):198-207. doi:10.4995/ega.2018.9810SWORD198207233

Heritage Building Information Modeling (H-BIM) Applied to A Stone Bridge

Certain historical works of civil engineering should be preserved as heritage monuments and when possible should continue serving the function they were designed for. Old stone bridges could be sustainably maintained but their conservation requires accurate documentation. In this study, we have scanned Ízbor bridge (1860) in Spain, and to facilitate conservation, we have modeled the ancient bridge using BIM (building information modeling). We propose a method and a model for this kind of bridge to be used as a reference for similar heritage monuments. Ízbor bridge modeled in this way will be useful for government planning and conservation agencies

New Drawings of the Alhambra: Deformations of Muqarnas in the Pendentives of the Sala de la Barca

Architectural heritage preservation and sustainability need advanced graphic techniques in order to document and understand the disposition/composition of plaster muqarnas, a fragile construction element. The muqarnas are key elements in the Nasrid architecture developed during the 14th century in the Alhambra complex, nowadays part of World Heritage. As a case study, this analysis focuses on the muqarnas pendentives of the Sala de la Barca in the Comares Palace. After examining both explanations and drawings published by architects Jones and Goury from 1842 to 1845, our research provides new drawings (plans and elevations) derived from laser scanner technology. Theoretically, though muqarnas are composed of simple geometrical shapes, these new drawings unveil important deformations hitherto unknown, and which have not been studied yet by other bibliographic references. Finally, we provide some considerations about the causes of these deformations and the monument sustainability across the time and the images’ capacity to show the muqarnas complex shapes in a reliable way

Monitorización de una excavación arqueológica usando fotogrametría y modelos digitales del terreno (MDT). El caso de estudio de Barranco León, Orce (Granada, España)

In this paper, we describe and discuss emergent digital technologies employed for monitoring the excavations at the archaeological site of Barranco León (Granada, Spain) between 2017 and 2020. The method entails the following material requirements: a total station, a conventional camera, a computer and a software that integrates photogrammetry algorithms; in terms of human resources, the presence of an engineer for the first day of the excavation to set up the methodological process and trained excavation staff to perform said method on a daily basis is necessary. Here we present the daily workflow for monitoring archaeological excavations introduced at the site, followed by an estimation of the costs and a summary of the results obtained. The method introduced here is based on the height difference of Digital Elevation Models (DEMs) computed on successive days using photogrammetric techniques. It is a non-invasive method, which requires less than 8% of the economic resources of the excavation and can be carried out in less than 15 minutes. This allows the excavation director to have an accurate and visual idea of the excavation process in order to make appropriate decisions. In addition, from the results obtained in the method (differences in DEM of every two days), other derived results can be obtained such as the exact location of the archaeological remains extracted based on their size. These features highlight the relevance and applicability of this approach to a wide range of archaeological sites.En este artículo, describimos y discutimos las tecnologías digitales emergentes utilizadas para la monitorización de las excavaciones del yacimiento arqueológico de Barranco León (Granada, España) entre las campañas de 2017 y 2020. El método implica el uso de los siguientes recursos materiales: una estación total, una cámara de fotos convencional, un ordenador y un programa que integre algoritmos de fotogrametría; referente a los recursos humanos, es necesaria la presencia de un ingeniero durante el primer día de la excavación para establecer el proceso metodológico y un excavador entrenado para llevar a cabo dicho método diariamente. Aquí, presentamos un flujo de trabajo diario para la monitorización de la excavación de un yacimiento arqueológico, seguido de una estimación de los costos y un resumen de los resultados obtenidos. El método presentado se basa en la diferencia de altura de los modelos digitales del terreno (MDT) calculados en sucesivos días utilizando técnicas fotogramétricas. Es un método no invasivo, que requiere menos del 8% del coste total de la excavación y se puede llevar a cabo en menos de 15 minutos. Esto permite que el director de la excavación tenga una visión precisa y una idea visual del proceso de excavación para tomar las decisiones adecuadas. Además, a partir de los resultados obtenidos en el método (diferencias en MDT de cada dos días), se pueden obtener otros resultados derivados como la ubicación exacta de los restos arqueológicos extraídos en función de su tamaño.Junta de Andalucia BC.03.032/17FEDER 2020 Operative Program Research Project A-HUM-016-UGR1