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The estimation of rockfall frequency for the quantitative assessment of rockfall hazard is challenging when there are not records of previous events. The aim of this study is to investigate the correlation between the rockfall frequency and the geometry of the overhanging rock blocks, at rocky slopes. The investigation takes place for seven rocky slopes along a coastal road in Northern Spain, and it is based on 15 years of rockfall data. A field survey of these slopes took place between May and June 2022, using a terrestrial laser scanner as well as ground and aerial photogrammetry from UAVs, in order to build three-dimensional digital models. Then, the geometrical attributes of the existing overhanging rocks were measured on the models. The surface area and the width of the latter were calculated. The correlation between the rockfall frequency and the sum of the overhanging areas at each slope was assessed. A good linear correlation was indicated between the normalized per slope area number of rockfalls and total overhang area (R2 = 0.9013) and between the respective normalized per unit of road length parameters (R2 = 0.9594). The magnitude-frequency relationship for the rockfall events that occurred at the seven slopes follows a power law distribution with exponent −0.65. [ABSTRACT FROM AUTHOR]

Accessible palaeontological sites conform highly adequate out-of-school environments for meaningful learning experiences regarding formal and non-formal teaching of geosciences. With a perspective of international cooperation, two correlative Cenomanian–Turonian (Upper Cretaceous) outcrops from the Iberian Peninsula have been chosen as the focus of this project—the sections of Figueira da Foz (Portugal) and Tamajón (Spain)—along with the Palaeontological and Archaeological Interpretation Centre of Tamajón (CIPAT). Virtualization of fossil samples and sites has been undertaken by means of phase-shift scanning, photogrammetry, and small object scanning by structured light and laser triangulation, resulting in three-dimensional virtual models of the main fossil tracks and invertebrate fossil samples. These virtual fossils have allowed the development of transdisciplinary didactic activities for different educational levels and the general public, which have been presented as file cards where the age of participants, objectives, multiple intelligences, European Union key competences, needed resources, development, and further observations are specified. This work aims to contribute to improving the design and development of didactic sequences for out-of-school education at these sites, organizing effective transdisciplinary teaching tools, and developing awareness, values, and responsibility towards geoheritage. [ABSTRACT FROM AUTHOR]

El Cerro de los Batallones is one of the most important fossil sites of the Miocene. The quantity and preservation of its fossil remains have allowed us to describe many new mammal species. One of these is Hispanomys moralesi, a derived species of the Tribe Cricetodontini, a wide group of rodents with great importance in the faunal assemblage during the Miocene. Unlike most fossil micromammals in this fossil site, we have obtained skull remains that preserve never recorded anatomical structures in this time interval. Due to the fragility of the material, it could only be studied in detail using X-ray micro-computed tomography (µ-CT Scan). With this technique, we obtained three-dimensional models of 12 skulls of Hispanomys moralesi, in which different osteological parts have been described. In this way, we compared the morphological variation of the skull with other fossil cricetids and concluded that Batallones' species is an opisthodont rodent, with a relatively elongated rostrum, a robust base of zygomatic arches and big-sized tooth rows. Opisthodont incisor characterises omnivore and herbivore diets in rodents. Therefore, these new findings of Hispanomys moralesi could allow us to describe the dietary affinities of this extinct species. [ABSTRACT FROM AUTHOR]

Tidal currents can propagate tens of kilometres landward from the shoreline, forming dense networks of meandering channels, which drain vegetated areas and range in width from tens to hundreds of metres. Sedimentary products of these inland tidal channels are poorly documented in the stratigraphic record, as most studies on tidal processes occurring in inland areas are focused on fluvio‐tidal interaction. The present study contributes to filling this gap, investigating Late Maastrichtian meandering‐channel deposits of the Tremp‐Graus Basin (Southern Pyrenees, Spain). These deposits accumulated in a growth syncline, which allowed the development of a 20 to 30 km wide, 80 to 100 km long, tidal embayment. Sporadic occurrence of poorly‐developed rhythmites and bidirectional currents confirms the occurrence of tidal processes, whereas their local dominance is inferred from several pieces of evidence, including: (i) disproportion between depth of the larger channels and related catchment area; (ii) landward‐accretion of point‐bar bodies; (iii) landward fining of point‐bar bodies, and (iv) reconstruction of palaeo‐flow patterns at the meander bend scale. This work shows that three‐dimensional architectural modelling and reconstruction of bar planform transformation styles can provide a critical contribution to the understanding of tidal control on sedimentation in inland areas. [ABSTRACT FROM AUTHOR]

Three-dimensional surveying with a terrestrial laser scanner (TLS) has implied a revolution in the field of 3D modeling, as this methodology provides detailed point-clouds with simplified processes of capture. In addition to the point-clouds, other outputs can be obtained, such as ortho-images, virtual itineraries, 2D cartography, and meshes, which implies a second avenue of multimedia products, such as 3D Portable Document Format (PDF) files and interactive applications. All these options are interesting for the management and broadcast of cultural heritage. The works that have been developed in this research are aimed at setting a workflow for the TLS surveying works and subsequent data management for the generation of a 3D model of the Caliphal Gate of Ceuta, which is considered as one of the most important medieval findings in Spain in recent years, and its immediate surroundings. This model and the different outputs that have been obtained from it allow for the continuation of the historiographic analysis of the complex, while documenting a partial stage in the development of the works of enhancement. In addition to this, these products are not only useful in terms of conservation studies or enhancement, as they are also suitable for the dissemination of the site. Special attention has been set on the paid suitable software for data management while generating the outputs, and for its application by the final users. [ABSTRACT FROM AUTHOR]

The students of the Defense University Center at the Spanish Naval Academy (Marín, northwest of Spain) attend both the military studies and mechanical engineering degrees. These students are the future officers of the Spanish Navy. Among them, the Marine Corp students attend subjects focused on topography, Geographic Information Systems (GIS) and an amphibious landing. In this framework, this paper presents an example of an application of the use of physical models for a better understanding of the terrain, as well as for landscape design or military planning. Through the use of different GIS and Computer-Aided Design software, the students have to demonstrate their capabilities to create and produce three-dimensional (3D) printed models. This work shows how the use of printed scale models of the terrain offers visualization advantages and more understanding to students when compared with virtual models or traditional maps. Additionally, a methodological approach is presented aiming to produce 3D-printed models using open data sources and free license software. From a point cloud of data, this software allowed creating and editing the virtual model (scales, vertical exaggeration, smooth, etc.), as well as to merge different point clouds. The methodology was applied to the Island of Tambo (Galicia, Spain). Using Light Detection and Ranging data, several printed scale models were elaborated on, including the Digital Terrain Model and Digital Elevation Model. Additionally, a bathymetric model was created, aiming to assist in the design of an amphibious operation. [ABSTRACT FROM AUTHOR]

There are many healthcare facilities in Spain that were built throughout the second half of the 20th century, and compose an interesting built heritage designed by outstanding architects of the architectural avant-garde. Some of them were included in the DOCOMOMO's list of buildings to be preserved and documented. As a consequence, every intervention on the hospitals' heritage requires a special attention and needs a deep knowledge of the building in advance of taking action. On the other hand, such a particular heritage is being continuously updated according to the new standards that derive from the current tendencies in hospital design, and also from advances in healing techniques. In this context, 3D Modelling and virtual reality should have a decisive impact on the way hospitals' complex spaces are designed, as they become useful tools for describing the previous stages of the buildings, as well as the impacts of new proposals. They can even change our experience of the built environment. As a step forward, we are developing a methodology to be applied to hospital design where these tools, together with BIM models -and in the near future, high-end immersive VR systems- play an important role. [ABSTRACT FROM AUTHOR]

Abstract A new methodology to identify discontinuity sets at the tunnel face based on the Structure from Motion (SfM) photogrammetric technique is proposed. The work focuses on the performance of this technique when employed to characterize the ground mass under real tunneling conditions, illustrating its possibilities and analyzing several aspects that affect the quality of the obtained results. By means of a set of overlapping photographs from the tunnel face, SfM constructs a 3D point cloud model, from which discontinuities are identified using a discontinuity set extractor software. To orientate and scale the digital model, an easy-to-use "portable orientation template", specifically developed for this work, is employed. The proposed methodology is applied to two real tunnels under construction in Northern Spain. Its results are compared with those obtained with a traditional analysis based on manual compass measurements. Results show that the SfM methodology provides an adequate characterization of the structure of the rock mass, identifying the same number of discontinuity sets as the compass measurements approach and with differences in orientation that are within the uncertainty range associated to manual measurements. Only one sub-horizontal set presented higher orientation differences, but this is mainly due to the presence of shotcrete at the face. In addition to the advantages of a "distant" measurement technique—e.g., health and safety advantages, capability to characterize unreachable areas, etc.—, as well as to the advantage of its reduced cost, the proposed SfM methodology and its associated tools allow one to represent planes associated to each discontinuity set back into the original 3D digital point model, and to perform detailed analyses that clarify and improve the obtained results. Finally, an analysis about the minimum number of photographs needed to adequately characterize the tunnel face is conducted, with results showing that around 15 good quality photographs are enough for tunnel faces with excavated areas of about 50 m2. [ABSTRACT FROM AUTHOR]

Abstract: In this article, the optimal design of a road joining two terminals is investigated. A geometric model is proposed including horizontal transition curves and vertical curves, obtaining parameterizations for the central axis of the road as well as for its entire surface. These parameterizations allow to express and compute, with great simplicity, the major infrastructure costs, including land acquisition, clearance, pavement, maintenance, and earthwork, where multiple layers of materials with different costs can be handled. The road design problem is formulated as a smooth constrained optimization problem and a two‐stage algorithm is suggested for its numerical resolution. Finally, numerical results are presented in an academic test and in a case study that propose designing a bypass in a Spanish national road (N‐640) to avoid crossing Monterroso's town center. [ABSTRACT FROM AUTHOR]

In the context of the Western European Acheulean Project, this study aims to characterize Acheulean technology in Western Europe through the analysis of handaxes and cleavers from 10 key sites (Britain 4, France 4, and Spain 2) to acquire a regional view of the occupation. The historically different systems used to categorize and analyze the data have made it difficult to compare results. Here we apply a unified and simple method (Western European Acheulean Project) that combines the traditional technological and metrical analysis of assemblages containing handaxes and cleavers with an in-depth geometric morphometric approach using three-dimensional models. This approach allows us to achieve a regional interpretation that identifies innovations through time and shaping strategies across the area. Our findings indicate the existence of two main technological groups in the sampled record: 1) northwestern and central France and Britain, from MIS 17/16 to MIS 11, and 2) Atlantic edge (Atapuerca in Spain and Menez-Dregan in France), from MIS 12/11 to MIS 8. Based on our technological analysis, the shaping of handaxes and cleavers was developed through time as a continuum of accumulative actions, with longer and more complex shaping strategies over time. Shaping technology shows traditions of manufacture over both time and geographical areas, which suggest cultural diffusion. Our geometric morphometric analysis further helped to identify not only general trends but also local adaptations in handaxe forms. Based on our findings, there were no apparent sudden innovations, but rather the application and development of specific techniques to refine size and shape. [ABSTRACT FROM AUTHOR]

The graphic survey of elements that belong to our Architectural Heritage, is now, at the beginning of the 21st Century, carried out with the help of a 3D laser scanner. But this system is useless if our "Building" no longer exists. From this system, we can move onto a photogrammetric survey, basing the work on images and intervention projects carried out on the building. But another problem arises when the available images are background images and not suitable for application to photogrammetry. In addition, if we don´t have any available intervention projects on the building or they don´t exist, we only have the original project and the ability of the architect, once his project has been built, to have been as faithful as possible to the original drawings he made at the time he was given responsibility for the job by the customer. This is the situation in which we find the "disappeared" Ruzafa Market in Valencia, projected by the architect Jose Maria Manuel Cortina Perez. [ABSTRACT FROM AUTHOR]

New photogrammetric survey techniques such as SfM photomodeling allow us to document the cultural heritage through textured three-dimensional models that can be showed via the Internet through the recent repositories of 3D models, allowing suitable interactive viewing from any computer or mobile device. Even reaching a totally immersive visualization mode, when using a virtual reality viewer such as the economic Google Cardboard. This implies a great advance for the enhancement and dissemination of heritage. In this article we will discuss the application of these new techniques and recent viewing platforms that have been used to create a virtual museum, accessible from the Internet, which shows the Romanesque capitals of the cloister of the Monastery of San Cugat, its symbolism and the possible theories connecting them with the music. [ABSTRACT FROM AUTHOR]

The following article is a part of my doctoral thesis entitled: "De la QASABAT al-QADIMA a la ALCAZABA ROJA", which provides a study on the Alhambra's Alcazaba, drawn up thanks to the wide and various literature available. In this context, I focused my research on the "Puerta de las Armas", which was a key element in the life of the Alcazaba and the Ciudadela de la Alhambra. In order to know the universal values of the Alcazaba, we analyze one of its elements as a defensive construction model which is used as a reference and example of military building, which adapting itself in the environment and making use of the profits of it, was modifying and fitting with the necessities of that moment. This research provides a detailed description of the element starting from its historical evolution and architectural characteristics, concluding with its new and actualized planimetric surveys and infographics. [ABSTRACT FROM AUTHOR]

In recent years, the application of geomatics tools in archaeology has proved to be very useful to obtain meaningful knowledge of the 3D reconstruction of archaeological remains and semantic classification of the 3D surface. These techniques have proven to be an effective solution for the 3D modeling and the extraction of many spatial features on an archaeological site. However, novel methodologies as well as new data exploitation strategies are required to exploit these geospatial data for natural and cultural heritage documentation, monitoring, and preservation. In this paper, we have studied unique archaeological ruins, a Mozarab church in Al-Andalus, using high-resolution RGB images, which was taken by a drone. Thus, a 3D reconstruction of the ruins and the surrounding environment is carried out in order to characterize it on a dense point cloud. Then, a digital elevation model (DEM) was calculated in order to identify critical slope lines, which are significant to determine where the structure of the church was built. Our results can be used for the development of an architectural project and thus a virtual recreation of these archaeological ruins was performed. [ABSTRACT FROM AUTHOR]