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Classifying crops using satellite data is a challenge, especially since most crops have similar growth cycles. Due to their different characteristics and chlorophyll content, different crops exhibit subtle differences in their reflectance spectra. This study uses a data-driven approach to build a series of deep learning models to classify 36 different land covers in Steele County and Traill Country, North Dakota, US. A Google Earth Engine workflow was implemented to generate a composite layer containing Sentinel 1 and Sentinel 2 satellite data and surface crop data over the study area. 200,000 sample points were generated on this layer, 140,000 for training dataset, 30,000 for validation dataset and 30,000 for testing dataset. Each sample point contains the values of 12 months of SAR and spectral data. In this way, a two-dimensional feature matrix of the time dimension and spectral band dimension (bands refer to specific wavelengths of data in remote sensing imagery and other type of data like NDVI) is generated for each sample point. The training dataset of the model is composed of the feature matrix of these sample points, and the surface crops as labels correspond to the feature matrix. Since this is a dataset with two-dimensional features, this research uses four deep learning models: Dense Neural Network (DNN), Long short-term memory (LSTM), Convolutional neural network (CNN) and Transformer. Among them, the Transformer model based on the self-attention mechanism performed the best, with a comprehensive accuracy rate of 85%, and the classification accuracy rate of crops with more than 2,000 sample points in the training data set reached more than 90%.

The archaeological site of Tiwanaku is among the most important examples of Bolivian archaeology and UNESCO World Heritage Site since 2000. This works reports a geomatic-based surveying and modelling methodology applied to a ritual receptacle excavated from the semi-subterranean temple in the archaeological complex. A high-resolution 3D survey was conducted through structured-light projection scanning and post-processing operations were carried out to emphasize surface details. Most of the operations were conducted in open-source software, with the aim to establish a quick and repeatable methodology to be applied to similar case studies. The final outputs, consisting of geometry projections (unrolled meshes), digitally enhanced surfaces and vector graphics can support the work of archaeologists in interpreting the iconography depicted on the receptacle and to conduct further studies to shed light about culture and religion of the civilization that inhabited Tiwanaku.

Global warming and changes in Earth’s weather patterns are the main consequences of climate change, and bioclimate discomfort has significant public health problems, especially for the elderly. Normally, the thermal characteristics of urban areas are poor due to a phenomenon known as urban heat island. Mobile and fixed temperature measurements were performed on 19 March 2021 in the city of Bologna, Italy. Mobile measurements took place with a car, along a 75-km transect, starting at 22:16 with a duration of 2 hours and 41 minutes, while fixed measurements were done using 15 present weather stations and also placing five thermometers in the city center. Various interpolation models (i.e., Traditional, Voronoi Tessellation, Global Trends, Triangulated Irregular Networks, Inverse Distance Weighting and Kriging) were applied to correct the mobile measurements using fixed data. Kriging fulfilled the best result with a correlation coefficient of 0.99 compared to the raw temperatures.

In this paper some experiences in 3D modelling of objects with very high-resolution are described, carried out by the DICAM Geomatics group of the University of Bologna in multi-disciplinary contexts within the field of the Civil Engineering. In all the addressed case studies the main aim is the generation of a 3D model of the surface at a sub-millimetric scale, allowing a very accurate characterization of the surface geometry, useful for different purposes. 3D scanning and Structure from Motion photogrammetry have been used to generate the 3D models. In the paper the encountered problems and the adopted solutions in data surveying and processing are underlined, also discussing the added value of very high-resolution 3D modelling in multi-disciplinary activities.

This paper shows an application of image-based 3D modelling concerning an interesting case study in the field of Cultural Heritage, a safe located in the Obellio Firmo domus in Pompeii (Italy), one of the largest and most complex houses in the ancient city. The object was strongly deformed by the eruption of Vesuvius in 79 A.D. and is currently protected by a permanent glass that helps to preserve it over time. The surveying activities and processing methodology is explained, based on Multi-View Structure from Motion technique, as well as the unconventional solution adopted during the images acquisition. Finally, an attempt will be presented to reconstruct the hypothetical original three-dimensional appearance and shape of the safe.

In the field of Cultural Heritage, the availability of a complete, detailed and photo-realistic 3D model of the objects of interest permits to describe all the aspects related to geometry, colours and materials, as well as the work techniques and the decay state. Besides, it offers multiple possibilities for the documentation, the analysis and the study.This paper describes the experience, carried out by the DICAM Geomatics group of the University of Bologna, about the 3D digitisation of two important statues of Neptune, by means of the integration of 3D image-based and range-based techniques. The two artworks, both realized by the sculptor Giambologna, are the big bronze statue of the god adorning the homonymous fountain, one of the most symbolic monuments of the city of Bologna, and its archetype, exhibited in one of the civic museums.The obtained 3D models, beyond the important function of documentation, knowledge and preservation of the two objects, also permit a comparison between the small archetype, conveniently scaled, and the big final statue. In the manuscript all the surveying and data processing operations concerning the objects digitisation are described. Particular attention is paid to the problems related to the scale of the archetype and the comparison between the two obtained 3D models, with the aim to evaluate and represent the occurred changes.

The analysis of the vertical movements of the soil in the Po River plane of the Emilia-Romagna Region (Italy) was updated through an interferometric analysis referred to the 2011–2016 time-span. This activity is a continuation of previous studies on the state of knowledge of vertical soil movements in the same area, analyzed firstly by levelling and GNSS and more recently by SAR interferometry for the periods 1992–2000, 2002–2006, 2006–2011, on behalf of the Emilia-Romagna Region. The survey area analysed was approximately 13 300 km2, which corresponds to the territory of the regional plain. The interferometric dataset was calibrated through the use of velocity time series of several permanent GNSS stations. Among the 36 stations analysed, 22 were included in the study area: 16 were used for the calibration and 6 as check points). The velocities required for the calibration of the SAR analysis were calculated in the period following the important seismic events that struck the territory of the Emilia Romagna Region in May 2012. The interferometric analysis was carried out by TRE ALTAMIRA using the SqueeSAR™ technology. In particular, in order to update the interferometric dataset to 2016, it was necessary to perform a joint processing of the available RADARSAT-1 data and of the data acquired by the RADARSAT-2 satellite using a specific operating mode of the SqueeSAR™ algorithm known as stitching; this approach allowed the joint processing of images acquired in the same geometry by these two satellites. The study of the time series of the GNSS permanent stations used to provide the velocity datum to the interferometric analysis, is described, and the results of the SqueeSAR™ interferometric processing are reported. Statistical analyses on the spatial distribution and the type of scatterers have been performed during the screening and validation procedures of the dataset, and for the identification and removal of the outliers. Finally, the resulting map is described in order to analyse the measured soil movements with respect to the results obtained in past analyses, and the possible geological and human-induced causes, which could have produced them.

Detailed three-dimensional reconstruction of heritage objects is crucial for different purposes, such as analysis, preservation and maintenance, among others. Geomatics techniques allow acquiring complex and comprehensive information about geometry and current conditions of the surveyed objects in a short time, which is a great advantage for documentation and historical archives. The reconstruction of three-dimensional models is often performed using either image-based techniques, mainly Close Range Photogrammetry (CRP), including Structure from Motion approaches (SfM), or range-based techniques, such as Terrestrial Laser Scanning (TLS). These approaches have been widely applied in the field of Cultural Heritage to support multidisciplinary studies, from simple documentation to the monitoring of historical buildings, in restoration works or for structural analysis checks.The present paper aims at exploring the potential contribution of Geomatics to Structural Engineering, by investigating capabilities and advantages of TLS for a vertical structure. The experiments presented herein were carried out in a notable case study, the San Luzi church, located in Zuoz (Switzerland) in the Upper Engadin. Its bell tower is about 60 m high and is equipped with four bells. Strong vibrations caused by the ringing of the bells have been observed in the past, and a structural model was desired to enable numerical evaluations of the response of the tower to various load situations by FEM.

In 2016, the Municipality of Bologna (Italy) has undertaken the restoration of one of the symbols of the entire city, the Fountain of Neptune, in evident state of degradation. The works have touched upon all the aspects of this complex object and the project has seen involved the Municipality and the University of Bologna, the Istituto Superiore per la Conservazione e il Restauro (ISCR) (Rome) and the Visual Computing Lab of the CNR – ISTI (Pisa), in a modern and highly multi-disciplinary approach.One of the key elements of the project was made up by the creation of an information system ad hoc developed to permit, in an innovative, efficient and user-friendly way, the collection, sharing, management and analysis of all the information and data related to diagnostics and restoration actions. The base of the information system is a very detailed 3D model of the monument, realized by means of the most modern techniques for objects 3D modelling (laser scanning, digital photogrammetry and 3D scanning) integrated together with the aim to obtain a photo-textured 3D model characterized by a sub-millimetre precision level in the geometric description and a high perceptive fidelity of colour reproduction.The surveying activities and data processing, performed by the DICAM Geomatics group of the University of Bologna (with the collaboration of the MCM Company of Rome), are described in the paper, with considerations on the problems encountered and the procedures and solutions adopted. The information system has been developed by CNR-ISTI.

GAMHer (Geomatics data Acquisition and Management for landscape and built Heritage in a European perspective) is a three-year research project financed under the Italian PRIN 2015 framework (Progetti di Ricerca di Rilevante Interesse Nazionale). The project, started in February 2017 under the University of Bologna coordination, links other 5 Italian research groups mainly involved in Cultural Heritage (CH) documentation and data management: Politecnico di Milano, Politecnico di Torino, IUAV Venice, University of Florence, University of Cassino and Southern Lazio and University of Bergamo.GAMHer aims at exploiting some research and practical challenges in those disciplines devoted to generate 3D models for objects related to both landscape and built heritage; primary focus is then on digital photogrammetry and 3D scanning. These techniques are more and more applied in different contexts, having as the main subjects monuments, buildings, natural and urban landscapes. Some critical points however remain for their implementation, also facing to the new European directives, strictly connected to the requirement of the Digital Agenda for Europe. A wider use of digital data has to be achieved, in Europe as well as internationally, and therefore an analysis of the current developments is significant, together with a critical assessment of their performances.

Terrestrial remote sensing techniques, including both Terrestrial Laser Scanning (TLS) and Close-Range Photogrammetry (CRP), have been recently used in multiple applications and projects with particular reference to the documentation/inspection of a wide variety of Cultural Heritage structures. The high density of TLS point cloud data allows to perform structure survey in an unprecedented level of detail, providing a direct solution for the digital three-dimensional modelling, the site restoration and the analysis of the structural conditions. Textural information provided by CRP can be used for the photorealistic representation of the surveyed structure. With respect to many studies, the combination of TLS and CRP techniques produces the best results for Cultural Heritage documentation purposes. Moreover, TLS and CRP point cloud data have been proved to be useful in the field of deformation analysis and structural health monitoring. They can be the input data for the Finite Element Method (FEM), providing some prior knowledge concerning the material and the boundary conditions such as constraints and loading. The paper investigates the capabilities and advantages of TLS and CRP data integration for the three-dimensional modelling compared to a simplified geometric reconstruction. This work presents some results concerning the Baptistery of Aquileia in Italy, characterized by an octagonal plan and walls composed by masonry stones with good texture.

3D city models are becoming increasingly popular and important, because they constitute the base for all the visualization, planning, management operations regarding the urban infrastructure. These data are however not available in the majority of cities: in this paper, the possibility to use geospatial data of various kinds with the aim to generate 3D models in urban environment is investigated. In 3D modelling works, the starting data are frequently the 3D point clouds, which are nowadays possible to collect by different sensors mounted on different platforms: LiDAR, imagery from satellite, airborne or unmanned aerial vehicles, mobile mapping systems that integrate several sensors. The processing of the acquired data and consequently the obtainability of models able to provide geometric accuracy and a good visual impact is limited by time, costs and logistic constraints. Nowadays more and more innovative hardware and software solutions can offer to the municipalities and the public authorities the possibility to use available geospatial data, acquired for diverse aims, for the generation of 3D models of buildings and cities, characterized by different level of detail. In the paper two cases of study are presented, both regarding surveys carried out in Emilia Romagna region, Italy, where 2D or 2.5D numerical maps are available. The first one is about the use of oblique aerial images realized by the Municipality for a systematic documentation of the built environment, the second concerns the use of LiDAR data acquired for other purposes; in the two tests, these data were used in conjunction with large scale numerical maps to produce 3D city models.

The research activities described in this contribution were carried out at San Leo (Italy). The town is located on the top of a quadrangular rock slab affected by a complex system of fractures and has a wealth of cultural heritage, as evidenced by the UNESCO’s nomination. The management of this fragile set requires a comprehensive system of geometrical information to analyse and preserve all the geological and cultural features. In this perspective, the latest Geomatics techniques were used to perform some detailed surveys and to manage the great amount of acquired geometrical knowledge of both natural (the cliff) and historical heritage. All the data were also georeferenced in a unique reference system. In particular, high accurate terrestrial laser scanner surveys were performed for the whole cliff, in order to obtain a dense point cloud useful for a large number of geological studies, among others the analyses of the last rockslide by comparing pre- and post-event data. Moreover, the geometrical representation of the historical centre was performed using different approaches, in order to generate an accurate DTM and DSM of the site. For these purposes, a large scale numerical map was used, integrating the data with GNSS and laser surveys of the area. Finally, many surveys were performed with different approaches on some of the most relevant monuments of the town. In fact, these surveys were performed by terrestrial laser scanner, light structured scanner and photogrammetry, the last mainly applied with the Structure from Motion approach.

GAMHer is a collaborative project that aims at exploiting and validating Geomatics algorithms, methodologies and procedures in the framework of new European regulations, which require a more extensive and productive use of digital information, as requested by the Digital Agenda for Europe as one of the seven pillars of the Europe 2020 Strategy. To this aim, GAMHer focuses on the need of a certified accuracy for surveying and monitoring projects with photogrammetry and laser scanning technologies, especially when used in a multiscale approach for landscape and built heritage documentation, conservation, and management. The approach used follows a multi-LoD (level of detail) transition that exploits GIS systems at the landscape scale, BIM technology and “point cloud based” 3d modelling for the scale of the building, and an innovative BIM/GIS integrated approach to foster innovation, promote users’ collaboration and encourage communication between users. The outcomes of GAMHer are not intended to be used only by a community of Geomatics specialists, but also by a heterogeneous user community that exploit images and laser scans in their professional activities.

The current dramatic episodes of destruction of archaeological sites have again highlighted the problem of the safeguarding the threatened heritage and, if possible, recovering those damaged by all the armed conflicts of the past. The historical photogrammetry offers the possibility to recover a posteriori the geometrical and material properties of destroyed structures, reconstructing their 3D model to document, study and maintain their memory, until to support their real anastylosis. The presented work is about the 3D reconstruction of the civic tower of the little town of Sant’Alberto, near the city of Ravenna, Italy. The tower, as a symbol of resistance and pride of the town's population, was destroyed in December 1944 by German troops in retaliation, when they were forced to leave the area. A city committee has subsequently collected all the historical evidence concerning the tower, including a series of photographic images that can be used for the photogrammetric reconstruction; the images calibration and orientation have been solved using the geometric information derived by a terrestrial laser scanner survey realized in the area where the tower was originally located. Despite the scarcity and very poor quality of the available images, the conducted photogrammetric procedure has allowed a complete and qualitatively satisfying object reconstruction, also thanks to the use of geometric constraint tools offered by the chosen software. The integration between the obtained model of the old tower and the 3D TLS survey of the square made it possible to reconstruct the ancient situation of the area.

The modern Geomatics techniques, such as Terrestrial Laser Scanner (TLS) and multi-view Structure from Motion (SfM), are gaining more and more interest in the Cultural Heritage field. All the data acquired with these technologies could be stored and managed together with other information in a Historical Building Information Model (HBIM). In this paper, it will be shown the case study of the San Michele in Acerboli’s church, located in Santarcangelo di Romagna, Italy. This church, dated about the 6th century A.D., represents a high relevant Romanic building of the high Medieval period. The building presents an irregular square plan with a different length of the lateral brick walls and a consequential oblique one in correspondence of the apse. Nevertheless, the different lengths of the lateral brick walls are balanced thanks to the irregular spaces between the windows. Different changes occurred during the centuries, such as the closing of the seven main doors and the building of the bell tower, in the 11th century A.D., which is nowadays the main entrance of the church. An integrated survey was realized, covering the exterior and the interior. The final 3D model represents a valid support not only for documentation, but also to maintain and manage in an integrate approach the available knowledge of this Cultural Heritage site, developing a HBIM system in which all the mentioned historical, geometrical, material matters are collected.

In the context of cultural heritage, an accurate and comprehensive digital survey of a historical building is today essential in order to measure its geometry in detail for documentation or restoration purposes, for supporting special studies regarding materials and constructive characteristics, and finally for structural analysis. Some proven geomatic techniques, such as photogrammetry and terrestrial laser scanning, are increasingly used to survey buildings with different complexity and dimensions; one typical product is in form of point clouds. We developed a semi-automatic procedure to convert point clouds, acquired from laserscan or digital photogrammetry, to a filled volume model of the whole structure. The filled volume model, in a voxel format, can be useful for further analysis and also for the generation of a Finite Element Model (FEM) of the surveyed building. In this paper a new approach is presented with the aim to decrease operator intervention in the workflow and obtain a better description of the structure. In order to achieve this result a voxel model with variable resolution is produced. Different parameters are compared and different steps of the procedure are tested and validated in the case study of the North tower of the San Felice sul Panaro Fortress, a monumental historical building located in San Felice sul Panaro (Modena, Italy) that was hit by an earthquake in 2012.

The present study aims to demonstrate the usefulness of GIS to support archive searches and historical studies (e.g. related to industrial archaeology), in the case of an ancient channel for mill powering near Cesena (Emilia-Romagna, Italy), whose history is weaved together with the history of the Compagnia dei Molini di Cesena mill company, the most ancient limited company in Italy. Several historical maps (about 40 sheets in total) inherent the studied area and 80 archive documents (drawings, photos, specifications, administrative acts, newspaper articles), over a period of more than 600 years, were collected. Once digitized, historical maps were analysed, georeferenced and mosaicked where necessary. Subsequently, in all the maps the channel with its four mills and the Savio river were vectorized. All the additional archive documents were digitized, catalogued and stored. Using the QGIS open source platform, a Historical GIS was created, encompassing the current cartographic base and all historical maps, with their vectorized elements; each archive document was linked to the proper historical map, so that the document can be immediately retrieved and visualized. In such a HGIS, the maps form the base for a spatial and temporal navigation, facilitated by a specific interface; the external documents linked to them complete the description of the represented elements. This simple and interactive tool offers a new approach to archive searches, as it allows reconstruction in space and time of the evolution of the ancient channel and the history of this important mill company.

The recent decades have seen a significant evolution of the methodologies and techniques for the monitoring of subsidence on a regional scale: from the traditional levelling technique to GNSS and finally to SAR interferometry. The case study of Emilia-Romagna, Italy, is a prime example of this evolution. As known, the Emilia-Romagna plain is subject to a phenomenon of subsidence with a natural and an anthropogenic component, both of varying amounts depending on the area. The first contributes a few mm/year; the second, particularly evident in the last 60 years, is mainly correlated to excessive withdrawal of fluids from underground and reaches higher values (in the past, subsidence rates of several cm per year were observed in the Po delta and near Bologna). The geodetic monitoring of subsidence started in the 1950s by different entities, establishing and measuring levelling networks of varying size and with various characteristics, mainly located where the phenomenon was most clearly manifest. These local initiatives were not able to provide a consistent understanding of the phenomenon throughout the entire Emilia-Romagna plain. The first regional-scale monitoring of the Emilia-Romagna plain was initiated in 1999, with a large levelling network (about 3000 km) and a coupled network of 60 GNSS points. In subsequent years, the monitoring approach has mainly focused on the most modern remote sensing techniques integrated with each other, with the adoption of the method DInSAR calibrated to a GNSS Continuous Operating Reference Stations (CORS) database. The application of DInSAR methods resulted in subsidence maps with a greater level of detail. The paper analyzes the methodology choices made during 1999–2012, through three successive campaigns that adopted and integrated the different techniques.

There is large consensus that demographic changes, the lack of appropriate environmental policies and sprawling urbanization result in high vulnerability and exposure to the natural disasters. This work reports some experiences of using multispectral satellite imagery to produce landuse/cover maps for the Dhaka city, the capital of Bangladesh, which is subject to frequent flooding events.The activity was conducted in collaboration with the non-profit organization ITHACA (Information Technology for Humanitarian Assistance, Cooperation and Action). The Landsat images acquired in 2000, 2002 and 2009 were used to evaluate the urban growth in order to support risk assessment studies; to identify areas routinely flooded during the monsoon season, the image of October 2009 (the most critical month for the effects of rain) was compared with two images acquired in January and February 2010. The analysis between 2000 and 2009 was able to quantify a very rapid growth of the metropolis, with an increase in built-up areas from 75 to 111 km2. The analysis highlights also a sharp rise of Bare soil class, likely related to the construction of embankments for the creation of new building space; consequently a decrease of cultivated land was observed. In particular, these artificial islands have been invading flooding areas. The change detection procedure also showed that the flooding in October 2009 affected about 20% (115 out of 591 km2) of the entire study area; furthermore these areas became wetlands and farmland over the next three/four months.

Identifying the right roofs to install solar panels inside a urban area is crucial for both private citizens and the whole local population. The aim is not easy because a lot of consideration must be made: insolation, orientation of the surface, size of the surface, shading due to topography, shading due to taller buildings next the surface, shading due to taller vegetation and other possible problems typical of urban areas like the presence of chimneys. Accuracy of data related to the analyzed surfaces is indeed fundamental, and also the detail of geometric models used to represent buildings and their roofs. The complexity that these roofs can reach is elevated. This work uses LiDAR data to obtain, with a semi-automatic technique, the full geometry of each roof part complementing the pre-existing building data in the municipal cartography. With this data is possible to evaluate the placement of solar panels on roofs of a whole city analyzing the solar potential of each building in detail. Other traditional techniques, like photogrammetry, need strong manual editing effort in order to identify slopes and insert vector on surfaces at the right height. Regarding LiDAR data, in order to perform accurate modelling, it is necessary to obtain an high density point cloud. The method proposed can also be used as a fast and linear workflow process for an area where LiDAR data are available and a municipal cartography already exist: LiDAR data can be furthermore successfully used to cross-check errors in pre-existent digital cartography that can remain otherwise hidden.

The results of two survey methods, geological photointerpretation and historical photogrammetry, are compared in order to evaluate the temporal evolution of a unstable slope located in the Tuscan-Emilian Apennines (Italy). Historical aerial photos of the area, derived from photogrammetric surveys conducted in 1954 (scale 1:60000), in 1971 (scale 1:20000), and in 1976 (scale 1:17000) were available. A photogrammetric flight was further conducted in 2000, at a scale of 1:4400, with a traditional GPS ground survey support. First, the results of photographic analysis with the photointerpretation method are presented: the landslides are described from a geological point of view, showing its temporal evolution. To quantitatively assess the landslide movements, Digital Terrain Models were generated by means of an analytical plotter and a digital photogrammetric workstation, with semi-automatic and automatic procedures. To generate these products, it was necessary to solve problems related to a lack of data concerning the aerial cameras used for the historical flights (internal orientation) and the difficulty identifying control points on the photos in order to define the external orientation. An unconventional photogrammetric methodology, based on identification of homologous points in zones considered outside the landslide area, has been there developed and tested to insert the various surveys into a single reference system.