Machine Learning for the Built Heritage Archaeological Study

The presence of artificial intelligence in our lives is increasing and being applied to fields such as medicine, engineering, telecommunications, remote sensing and 3D visualization. Nevertheless, it has never been used for the stratigraphic study of historical buildings. Thus far, archaeologists and architects, the experts in archaeology of architecture, have led this research. The method consisted of visually-and, consequently, subjectively-identifying certain evidence regarding the elevations of such buildings that could be a consequence of the passage of time. In this article, we would like to present the results from one of the research projects pursued by our group, in which we automated the stratigraphic study of some historic buildings using multivariate statistic techniques. To this end, we first measured the building using surveying techniques to create a 3D model, and then, we broke down every stone into qualitative and quantitative variables. To identify the stratigraphic features on the walls, we applied machine learning by conducting different predictive and descriptive analyses. The predictive analyses were used to rule out any blocks of stone with different characteristics, such as rough stones, joint ashlars, and voussoirs of arches; these are irregularities that probably show building processes and whose identification is crucial in ascertaining the structural evolution of the building. In supervised learning, we experimented with decision trees and random forest- and although the results were good in all cases, we ultimately opted to implement the predictive model obtained using the last one. While identifying the evidence on the walls, it was also very important to identify different continuity solutions or interfaces present on them, because although these are elements without materiality, they are of great value in terms of timescale, because they delimit different strata and allow us to deduce the relationship between them.Archaeology of Architecture in the old and the new world: from the stratigraphy of the buildings to the stratigraphy of the urban fabric"(PID2019-109464GB-I00), financed by the Spanish Ministry of Science and Innovation

Análisis clúster: un primer paso sobre técnicas cuantitativas en Arqueología de la Arquitectura

The proposal made in this article is based on the conviction that there are certain methods of analysis in archaeology that could be significantly improved if they incorporated quantitative techniques; one of those methods is undoubtedly that of the stratigraphic reading of elevations. In the course of this document, our background in this regard will be explained, by means of a brief summary. Although the starting point will be based on the initial more intuitive experiments, it will focus primarily on our latest mathematical-statistical trials. The text will identify how we are experimenting with methods of massive capture of geometric information, which through programming is later subjected to data mining, based on the use of multivariate analysis techniques with proprietary algorithms. Finally, we reflect on the future in which we envisage that the stratigraphic reading of elevations will reach a degree of automation very close to expert systems and artificial intelligence.La propuesta que se hace en este artículo parte del convencimiento de que existen ciertos métodos de análisis en arqueología que podrían mejorar notablemente si incorporaran las técnicas cuantitativas; uno de esos métodos es sin duda el de la lectura estratigráfica de alzados. A lo largo de estas líneas expondremos cual es nuestro bagaje al respecto, haciendo un breve recorrido que, si bien partirá de los primeros experimentos más intuitivos, se centrará prioritariamente en nuestros últimos ensayos de carácter matemático-estadístico. En el texto se apreciará cómo estamos experimentando con métodos de captura masiva de información geométrica que después, mediante programación, sometemos a una minería de datos basada en el empleo de algoritmos propios de las técnicas de análisis multivariante. Aportamos finalmente nuestra reflexión sobre un futuro en el que prevemos que la lectura estratigráfica de alzados alcanzará un grado de automatización muy próximo a los sistemas expertos y la inteligencia artificial

Del edificio al paisaje, una panorámica metodológica de la Arqueología de la Arquitectura en el banco de pruebas de Vitoria-Gasteiz (País Vasco)

The goal of this paper is to provide a general overview of some methodologies that have been tried out over the last two decades trying to increase the applicability of the Archaeology of Architecture. We will review the usual field of work‒the singular building‒to reach to the anthropized landscape. Practically all the experiences mentioned have been developed by the Research Group on Built Heritage of the UPV/EHU in the territorial area of the municipality of Vitoria-Gasteiz.El presente artículo está pensado para ofrecer una panorámica general de diversas metodologías que, respetando la perspectiva estratigráfica inherente a la Arqueología de la Arquitectura, se han ensayado en las últimas dos décadas con el fin de ampliar el horizonte de aplicabilidad de la disciplina, desde el ámbito habitual de trabajo que es el edificio singular, para llegar al paisaje antropizado. Prácticamente todas las experiencias de las que se habla han sido desarrolladas por el Grupo de Investigación en Patrimonio Construido de la UPV/EHU en el ámbito territorial del municipio de Vitoria-Gasteiz

Láser escáner y nubes de puntos. Un horizonte aplicado al análisis arqueológico de edificios

This paper analyses the laser scanner, a powerful tool for graphic recording of cultural heritage sites. Although attention will be drawn to those technical and logistical aspects and methods related to its employment, this report will mainly focus on its applicability on Building Archaeology, highlighting those diagnosing capacities which may help the stratigrapher to establish an evolutionary sequence of the building. The basis of this study is our work on San Miguel church in Vitoria-Gasteiz.En el siguiente artículo analizamos uno de los más modernos instrumentos de documentación gráfica del patrimonio, el láser escáner. Aunque profundizaremos en todos aquellos aspectos técnicos, logísticos y de método relativos a su empleo, nos centraremos en su efectiva aplicabilidad dentro del campo de la Arqueología de la Arquitectura, incidiendo en aquellas capacidades diagnósticas que pueden ayudar al estratígrafo a determinar la secuencia evolutiva de un edificio. Tomaremos como base nuestra experiencia en la iglesia de San Miguel de Vitoria-Gasteiz

Geometric documentation and virtual representation of San Martin’s church in Arlucea (Álava, Spain)

[ES] El edificio tiene planta rectangular de unos 30 x 15 metros con un interior con una altura de 10 metros. Cuenta con una torre anexa a los pies y un pórtico de piedra de ocho arcos de posible factura medieval. La antigua cabecera ha quedado como la sacristía actual.La documentación principal se ha realizado mediante estación total con medida sin prisma, completado en los elementos decorativos (ventanas y puerta de acceso) mediante pares fotogramétricos y con dibujo perspectivo. El modelo alámbrico se ha recubierto con texturas fotográficas mediante un programa desarrollado en el Laboratorio.[EN] It is a rectangular building of 30 x 15 meters and the ceiling is 10 meters high. It has a tower and a medieval portico.Main documentation was done with total station, completed with some perspective drawing and three stereopairs for windows and the main door. Wireframe model was wrapped with photographic textured in order to generate a virtual VRML model.Servicio de Patrimonio Histórico Arquitectónico de la Excma. Diputación Foral de Álava[ES] Memoria del proyecto (26 páginas + anexos) en formato PDF + 6 fotografías de documentación (formato JPEG).[EN] Report in Spanish (26 pages + appendices) in PDF format + 6 photographs (JPEG)

Auxiliary equipment for close range photogrammetry

[ES] Este artículo incluye información del siguiente proyecto de documentación geométrica:● LDGP_mem_012-1: "Documentación geométrica de las excavaciones de la Catedral de Santa María (Vitoria-Gasteiz). Mayo 2000-Junio 2003", http://hdl.handle.net/10810/7212● LDGP_mem_012-1: "Documentación geométrica de las excavaciones de la Catedral de Santa María (Vitoria-Gasteiz). Mayo 2000-Junio 2003", http://hdl.handle.net/10810/7212[EN] This paper includes information from the following project:[ES] Son muchos los artículos técnicos que se pueden encontrar sobre la aplicación de la fotogrametría de objeto cercano a la documentación del patrimonio; sin embargo, un aspecto sobre el que no es habitual encontrar información corresponde a los métodos e instrumentos necesarios para obtener de forma adecuada las fotografías y realizar las tareas topográficas en las dispares circunstancias que el patrimonio requiere. En este artículo se muestra el diseño y utilización de algunos elementos auxiliares utilizados para mejorar la realización de este tipo de pares fotogramétricos.[EN] There are many references where it is described the application of photogrammetric techniques to the documentation of the Cultural Heritage. However, it is not so easy to find texts concerning the auxiliary equipment used in order to get the better conditions for the photographs. In this paper we look over the design and use of some pieces of this kind of equipment

Geometric documentation and photogrammetric stereoplotting of the phases 1 to 5 of Labraza walls (Álava, Spain)

[ES] Se han documentado unos 140 metros de muralla que corresponde a los alzados suroeste y sur y que incluye la puerta de acceso principal del casco urbano.La documentación se ha realizado mediante pares estereoscópicos en película (negativos y diapositivas) obtenidos con una cámara semimétrica de 6x6 cm.[EN] Around 140 metres of the southern and east southern wall were documented. This section also contains the main entrance to the town.The documentation was done by means of photogrammetric stereopairs taken with a semi-metric camera of 6x6 cm.Arabarri (Sociedad Anónima de Gestión de Los Centros Históricos de Álava)[ES] Memoria del proyecto (13 páginas en formato PDF) + 6 fotografías de documentación (JPEG).[EN] General report (13 pages in Spanish and PDF format) + 6 photographs for documentation purposes

Temperature based maximum power point tracking for photovoltaic modules

In this article authors propose a temperature based Maximum Power Point Tracking algorithm (MPPT). Authors show that there is an optimal current vs maximum power curve that depends on photovoltaic (PV) module temperature. Therefore, the maximum power point (MPP) can be achieved in very few commutation steps if the control forces the PV module to work in temperature dependent optimal curve. Authors shows how this PV module temperature based MPPT is stable and converges to MPP for each temperature. In order to proof its stability, authors propose a Lyapunov energy function. This Lyapunov energy function has positive values for all values except into MPP given the PV module temperature. This Lyapunov energy function has negative increment along each time step. Hence, the stability of temperature based MPPT can be demonstrated. The proposed MPPT algorithm proposes a current set point. This current set point is obtained with instantaneous PV module power and temperature dependent maximum power vs optimal current curve. Stability is analysed for different temperature levels. Optimal current vs maximum power curve has been modelled by a line. The lines' coefficients depend on PV module temperature. Proposed Lyapunov energy function is not symmetric about equilibrium or MPP because MPPT algorithm and PV module dynamic have no symmetric behaviour about this equilibrium point."Development Agency of the Basque Country (SPRI) is gratefully acknowledged for economic support through the research project "Refrigeracion de dispositivos de alto flujo termico mediante impacto de chorro" (AIRJET), KK-2018/00109, Programa ELKARTEK.

Geometric documentation of the group made by Martiartu’s tower and San Antonio’s hermitage (Erandio, Bizkaia, Spain)

[ES] El conjunto está formado por la torre de Martiartu (de unas 16 x 16 metros de planta), la pequeña ermita de la San Antonio y el área circundante.La documentación de la torre se realiza mediante fotogrametría estereoscópica y rectificación fotográfica para la obtención de las ortoimágenes. La ermita de San Antonio y el entorno se ha documentado mediante estación total y mallado para crear un modelo de superficies tridimensional. Posteriormente se presentan los modelos 3D y la colección de planos.[EN] A group of two buildings: Martiartu’s tower (plan of around 16 x 16 meters), the small hermitage of San Antonio, and the surrounding area.The tower was documented by photogrammetric techniques: stereoplotting and rectification for the orthoimages. The hermitage and the surrounding was documented with total station. The model was meshed and presented as 3D product as well as a series of plans, elevations and cross-sections.Ayuntamiento de Erandio[ES] Memoria del proyecto (79 páginas) en formato PDF + 12 fotografías de documentación (formato JPEG).[EN] General report (79 pages in Spanish) format PDF + 12 photographs for documentation purposes (JPEG

Temperature based maximum power point tracking for photovoltaic modules

In this article authors propose a temperature based Maximum Power Point Tracking algorithm (MPPT). Authors show that there is an optimal current vs maximum power curve that depends on photovoltaic (PV) module temperature. Therefore, the maximum power point (MPP) can be achieved in very few commutation steps if the control forces the PV module to work in temperature dependent optimal curve. Authors shows how this PV module temperature based MPPT is stable and converges to MPP for each temperature. In order to proof its stability, authors propose a Lyapunov energy function. This Lyapunov energy function has positive values for all values except into MPP given the PV module temperature. This Lyapunov energy function has negative increment along each time step. Hence, the stability of temperature based MPPT can be demonstrated. The proposed MPPT algorithm proposes a current set point. This current set point is obtained with instantaneous PV module power and temperature dependent maximum power vs optimal current curve. Stability is analysed for different temperature levels. Optimal current vs maximum power curve has been modelled by a line. The lines' coefficients depend on PV module temperature. Proposed Lyapunov energy function is not symmetric about equilibrium or MPP because MPPT algorithm and PV module dynamic have no symmetric behaviour about this equilibrium point."Development Agency of the Basque Country (SPRI) is gratefully acknowledged for economic support through the research project "Refrigeracion de dispositivos de alto flujo termico mediante impacto de chorro" (AIRJET), KK-2018/00109, Programa ELKARTEK.