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Francesco MANCINI
Professore Associato
Dipartimento di Ingegneria "Enzo Ferrari"
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Pubblicazioni
2023
- A multi-temporal DInSAR-based method for the assessment of the 3D rigid motion of buildings and corresponding uncertainties
[Articolo su rivista]
Bassoli, E.; Vincenzi, L.; Grassi, F.; Mancini, F.
abstract
2023
- Multitemporal Analysis of Slow-Moving Landslides and Channel Dynamics through Integrated Remote Sensing and In Situ Techniques
[Articolo su rivista]
Parenti, Carlotta; Rossi, Paolo; Mancini, Francesco; Scorpio, Vittoria; Grassi, Francesca; Ciccarese, Giuseppe; Lugli, Francesca; Soldati, Mauro
abstract
The relationships between hillslope and fluvial processes were studied in a mountainous area of the Northern Apennines (Italy) where intermittent landslide activity has interacted for a long time with river morphodynamics. The aim of the study was to analyse such relationships in two study sites of the Scoltenna catchment. The sites were analysed in detail and monitored through time. A long-term analysis was carried out based on multitemporal photointerpretation of aerial photos. Slope morphological changes and land use modifications since 1954 were detected and compared with the evolution of the channel morphology. A short-term analysis was also performed based on two monitoring campaigns accomplished in 2021 and 2022 in order to detect possible slope displacements and channel-bed-level changes. The techniques used are global navigation satellite systems and drone photogrammetry accompanied by geomorphological surveys and mapping. The multitemporal data collected allowed us to characterise slope surface deformations and quantify morphological changes. The combination of various techniques of remote and proximal sensing proved to be a useful tool for the analysis of the surface deformations and for the investigation of the interaction between slope and fluvial dynamics, showing the important role of fluvial processes in the remobilisation of the landslide toe causing the displacement of a significant volume of sediment into the stream.
2022
- A simplified procedure to assess uncertainties in the estimation of the rigid motion of isolated buildings based on InSAR monitoring
[Relazione in Atti di Convegno]
Bassoli, E; Grassi, F.; Eslami Varzaneh, G.; Ponsi, F.; Mancini, F.; Vincenzi, L.
abstract
2022
- Contribution of anthropogenic consolidation processes to subsidence phenomena from multi-temporal DInSAR: a GIS-based approach
[Articolo su rivista]
Grassi, Francesca; Mancini, Francesco; Bassoli, Elisa; Vincenzi, Loris
abstract
The paper introduces an approach based on the combination of multi-temporal Differential Interferometric Synthetic Aperture Radar and geographical information systems analysis to investigate and separate several contributions to subsidence phenomena over the municipality of Ravenna (Emilia Romagna, Italy). In particular, the relationship between displacements detected over built environment and consolidation processes after construction was assessed and filtered out from the subsidence map to quantify the local overestimation of subsidence phenomena due to the mentioned processes. It requires descriptive attributes related to the age of construction and intended uses. The outcomes of the present study highlight ground consolidation processes that seem to be active over areas settled in the last 30 years with a component contributing to vertical rates up to 3 mm/yr. Such contribution represents the 20% of the cumulative displacements reported for coastal villages where different sources of subsidence increase the vulnerability to coastal erosion. We discuss the contribution of consolidation processes over a couple of recently settled areas to separate among contributions and avoid the misinterpretation of effects due to other anthropogenic sources of subsidence.
2022
- Image-Based Monitoring of Cracks: Effectiveness Analysis of an Open-Source Machine Learning-Assisted Procedure
[Articolo su rivista]
Parente, Luigi; Falvo, Eugenia; Castagnetti, Cristina; Grassi, Francesca; Mancini, Francesco; Rossi, Paolo; Capra, Alessandro
abstract
The proper inspection of a cracks pattern over time is a critical diagnosis step to provide a thorough knowledge of the health state of a structure. When monitoring cracks propagating on a planar surface, adopting a single-image-based approach is a more convenient (costly and logistically) solution compared to subjective operators-based solutions. Machine learning (ML)- based monitoring solutions offer the advantage of automation in crack detection; however, complex and time-consuming training must be carried out. This study presents a simple and automated ML-based crack monitoring approach implemented in open sources software that only requires a single image for training. The effectiveness of the approach is assessed conducting work in controlled and real case study sites. For both sites, the generated outputs are significant in terms of accuracy (~1 mm), repeatability (sub-mm) and precision (sub-pixel). The presented results highlight that the successful detection of cracks is achievable with only a straightforward ML-based training procedure conducted on only a single image of the multi-temporal sequence. Furthermore, the use of an innovative camera kit allowed exploiting automated acquisition and transmission fundamental for Internet of Things (IoTs) for structural health monitoring and to reduce user-based operations and increase safety.
2022
- Influence of AGL flight and off-nadir images on UAV-SfM accuracy in complex morphology terrains
[Articolo su rivista]
Aguera-Vega, F.; Ferrer-Gonzalez, E.; Carvajal-Ramirez, F.; Martinez-Carricondo, P.; Rossi, P.; Mancini, F.
abstract
In the field of geosciences and engineering, situations arise where special attention have to be paid to the planning of the UAV-photogrammetric project, that is, terrain with complex geometry and steep slopes. The use of off-nadir imagery and flights at a fixed height above ground level (AGL) are postulated as possible factors to be considered to achieve high accuracies. The objective of this study is to evaluate the influence of image angle, frontal and side overlaps, and type of flight (above mean sea level (AMSL) or AGL), on the accuracy of the dense 3 D point cloud yielded by UAV-SfM. The results obtained showed that imagery with an angle between 20° and 35° in two perpendicular flight line directions, 90/90, 90/70 or 70/70 overlap and AGL flight is the optimal combination for best accuracy and high precision. With nadir imagery, the combination of factors that gives the most accuracy results are AGL flights with a 90/70 overlap.
2022
- Innovations in Photogrammetry and Remote Sensing: Modern Sensors, New Processing Strategies and Frontiers in Applications
[Curatela]
Mancini, Francesco; Pirotti, Francesco
abstract
2022
- Integrated Geomatics Surveying and Data Management in the Investigation of Slope and Fluvial Dynamics
[Articolo su rivista]
Parenti, Carlotta; Rossi, Paolo; Soldati, Mauro; Grassi, Francesca; Mancini, Francesco
abstract
In mountain environments, slope and fluvial dynamics often interact, and their relationship can be investigated through an integrated methodological approach. Landslides are a source of supplying sediments into riverbeds and can interact or interrupt the water course. Water courses can trigger or re-activate slope movements. The complexity of investigating the interaction between the two dynamics needs a complementarity of methods and techniques, combining remote and proximal sensing, geotechnical in situ surveys, and repositories and catalogue datasets. This leads to a synergistic use of all the heterogeneous data from different fields and formats. The present paper provides a literature review on the approaches and surveying procedures adopted in the investigation of slope and fluvial dynamics and highlights the need to improve the integrated management of geospatial information complemented by quality information. In this regard, we outline a geodatabase structure capable of handling the variety of geoscientific data available at different spatial and temporal scales, with derived products that are useful in integrated monitoring tasks. Indeed, the future adoption of a shared physical structure would allow the merging and synergistic use of data provided by different surveyors as well as the effective storing and sharing of datasets from a monitoring perspective.
2022
- PHOTOGRAMMETRIC AND FLUORESCENCE SOLUTIONS FOR MONITORING OF HABITAT FORMING ORGANISMS
[Relazione in Atti di Convegno]
Rossi, P.; Righi, S.; Parente, L.; Castagnetti, C.; Cattini, S.; Di Loro, G.; Falvo, E.; Grassi, F.; Mancini, F.; Rovati, L.; Simonini, R.; Capra, A.
abstract
The development and testing of innovative technologies and automated data analysis methodologies offer tools for the monitoring of complex marine ecosystems and the direct and indirect effects of climate change on natural heritage. Photogrammetric methods allow precise mapping of the underwater landscape as well as detailed three-dimensional (3D) reconstruction of marine structures, improving the study of complex marine ecosystems. Moreover, fluorescence analyses can provide critical information about the health status of marine organisms. Analysing the variations in their self-fluorescence, allow for early detect changes in their physiological state. These applications provide very useful data to evaluate the health state of biodiversity-rich 3D biogenic structures and make measurements of fine-scale changes, with greater precision than existing methodologies. This contribution shows a multidisciplinary approach to the design, development, and implementation of a technological solution based on the above-mentioned optical measuring systems. Such a system is characterized by a reflex camera, LED-based light sources, and filters to allow the analysis of the self-fluorescence signal. The proposed solution aspires to improve the standardization of monitoring plans through non-destructive fine-scale accurate data collection for image analysis and multi-temporal comparisons, providing challenging stepping-stones for habitat-forming anthozoan management and restoration activities. Initial results of tests carried out in controlled conditions are shown. The photogrammetric approach resulted in 3D reconstructions that allow the monitoring of deformations at millimetre scale. The fluorimetry methodology allowed to obtain high-resolution images with great repeatability, which enabled the identification of stressful status even in absence of geometric deformations. The proposed approaches and obtained results are discussed, together with potential issues related to their implementation in a real-world context adopting remotely operative vehicles.
2022
- UAV Photogrammetry and GIS Interpretations of Extended Archaeological Contexts: The Case of Tacuil in the Calchaquí Area (Argentina)
[Articolo su rivista]
Orsini, Carolina; Benozzi, Elisa; Williams, Veronica; Rossi, Paolo; Mancini, Francesco
abstract
The scope and scientific purpose of this paper focuses on multiscale (aerial and terrestrial) photogrammetry as a support to investigations and interpretations in a multi-component archaeological site located in the Argentinian Cordillera (Calchaquí, Salta), known as Tacuil. Due to its scarce accessibility, as well as long-term problems associated with the interpretation of the visibility of this type of settlement, the use of aerial surveying was combined with the reconstruction of structures and complex soil morphologies by resorting to modern photogrammetric approaches (3D models and orthophotos). This dataset was complemented by a terrestrial survey to obtain extremely high resolution and detailed representations of archaeological features that were integrated in a GIS database. The outcome of photogrammetric surveying was fundamental in supporting the debate on the functionality of the site and his integration in a complex, socially constructed, ancient landscape. Finally, the present paper introduces the first complete map of Tacuil.
2021
- A workflow based on snap–stamps open‐source tools and gnss data for psi‐based ground deformation using dual‐orbit sentinel‐1 data: Accuracy assessment with error propagation analysis
[Articolo su rivista]
Mancini, F.; Grassi, F.; Cenni, N.
abstract
This paper discusses a full interferometry processing chain based on dual‐orbit Sentinel‐ 1A and Sentinel‐1B (S1) synthetic aperture radar data and a combination of open‐source routines from the Sentinel Application Platform (SNAP), Stanford Method for Persistent Scatterers (StaMPS), and additional routines introduced by the authors. These are used to provide vertical and East‐West horizontal velocity maps over a study area in the south‐western sector of the Po Plain (Italy) where land subsidence is recognized. The processing of long time series of displacements from a cluster of continuous global navigation satellite system stations is used to provide a global reference frame for line‐of‐sight–projected velocities and to validate velocity maps after the decomposition analysis. We thus introduce the main theoretical aspects related to error propagation analysis for the proposed methodology and provide the level of uncertainty of the validation analysis at relevant points. The combined SNAP–StaMPS workflow is shown to be a reliable tool for S1 data processing. Based on the validation procedure, the workflow allows decomposed velocity maps to be obtained with an accuracy of 2 mm/yr with expected uncertainty levels lower than 2 mm/yr. Slant‐oriented and decomposed velocity maps provide new insights into the ground deformation phenomena that affect the study area arising from a combination of natural and anthropogenic sources.
2021
- Innovations in photogrammetry and remote sensing: Modern sensors, new processing strategies and frontiers in applications (Editorial)
[Articolo su rivista]
Mancini, F.; Pirotti, F.
abstract
2021
- Needs and gaps in optical underwater technologies and methods for the investigation of marine animal forest 3D-structural complexity
[Articolo su rivista]
Rossi, Paolo; Ponti, Massimo; Righi, Sara; Castagnetti, Cristina; Simonini, Roberto; Mancini, Francesco; Agrafiotis, Panagiotis; Bassani, Leonardo; Bruno, Fabio; Cerrano, Carlo; Cignoni, Paolo; Corsini, Massimiliano; Drap, Pierre; Dubbini, Marco; Garrabou, Joaquim; Gori, Andrea; Gracias, Nuno; Ledoux, Jean-Baptiste; Linares, Cristina; Pulido Mantas, Torcuato; Menna, Fabio; Nocerino, Erica; Palma, Marco; Pavoni, Gaia; Ridolfi, Alessandro; Rossi, Sergio; Skarlatos, Dimitrios; Treibitz, Tali; Turicchia, Eva; Yuval, Matan; Capra, Alessandro
abstract
Marine animal forests are benthic communities dominated by sessile suspension
feeders (such as sponges, corals, and bivalves) able to generate three-dimensional (3D)
frameworks with high structural complexity. The biodiversity and functioning of marine
animal forests are strictly related to their 3D complexity. The present paper aims at
providing new perspectives in underwater optical surveys. Starting from the current
gaps in data collection and analysis that critically limit the study and conservation of
marine animal forests, we discuss the main technological and methodological needs for the investigation of their 3D structural complexity at different spatial and temporal
scales. Despite recent technological advances, it seems that several issues in data
acquisition and processing need to be solved, to properly map the different benthic
habitats in which marine animal forests are present, their health status and to measure
structural complexity. Proper precision and accuracy should be chosen and assured in
relation to the biological and ecological processes investigated. Besides, standardized
methods and protocols are strictly necessary to meet the FAIR (findability, accessibility,
interoperability, and reusability) data principles for the stewardship of habitat mapping
and biodiversity, biomass, and growth data.
2021
- Victoria land, antarctica: An improved geodynamic interpretation based on the strain rate field of the current crustal motion and moho depth model
[Articolo su rivista]
Zanutta, A; Negusini, M; Vittuari, L; Martelli, L; Cianfarra, P; Salvini, F; Mancini, F; Sterzai, P; Creati, N; Dubbini, M; Capra, A.
abstract
In Antarctica, the severe climatic conditions and the thick ice sheet that covers the largest and most internal part of the continent make it particularly difficult to systematically carry out geophysical and geodetic observations on a continental scale. It prevents the comprehensive understanding of both the onshore and offshore geology as well as the relationship between the inner part of East Antarctica (EA) and the coastal sector of Victoria Land (VL). With the aim to reduce this gap, in this paper multiple geophysical dataset collected since the 1980s in Antarctica by Programma Nazionale di Ricerche in Antartide (PNRA) were integrated with geodetic observations. In particu-lar, the analyzed data includes: (i) Geodetic time series from Trans Antarctic Mountains DEFormation (TAMDEF), and Victoria Land Network for DEFormation control (VLNDEF) GNSS stations installed in Victoria Land; (ii) the integration of on-shore (ground points data and airborne) gravity measurements in Victoria Land and marine gravity surveys performed in the Ross Sea and the nar-row strip of Southern Ocean facing the coasts of northern Victoria Land. Gravity data modelling has improved the knowledge of the Moho depth of VL and surrounding the offshore areas. By the integration of geodetic and gravitational (or gravity) potential results it was possible to better con-strain/identify four geodynamic blocks characterized by homogeneous geophysical signature: the Southern Ocean to the N, the Ross Sea to the E, the Wilkes Basin to the W, and VL in between. The last block is characterized by a small but significant clockwise rotation relative to East Antarctica. The presence of a N-S to NNW-SSE 1-km step in the Moho in correspondence of the Rennick Geo-dynamic Belt confirms the existence of this crustal scale discontinuity, possibly representing the tectonic boundary between East Antarctica and the northern part of VL block, as previously pro-posed by some geological studies.
2020
- Applications of Photogrammetry for Environmental Research
[Curatela]
Mancini, Francesco; Salvini, Riccardo
abstract
ISPRS International Journal of Geo-Information: special issue entitled "Applications of Photogrammetry for Environmental Research"
2020
- Detecting change in coral reef 3D structure using underwater photogrammetry: critical issues and performance metrics
[Articolo su rivista]
Rossi, P.; Castagnetti, C.; Capra, A.; Brooks, A. J.; Mancini, F.
abstract
This paper presents a multi-temporal underwater photogrammetric survey of a reef patch located in Moorea, French Polynesia, designed to detect a coral growth of 10–15 mm/year. Structure-from-Motion photogrammetry and underwater imagery allows the three-dimensional quantification of reef structural complexity and ecologically relevant characteristics at the patch scale. A high degree of accuracy and fine resolution are required in order to guarantee the repeatability of surveys over time within the same reference system, meaning a proper geodetic network and acquisition scheme are mandatory. Measuring tools and reference points were properly designed in order to constrain the photogrammetric reconstruction. The network adjustment, performed with distance and height difference observations, provided an average accuracy of ± 1.2 mm and ± 2.9 mm in the horizontal and vertical components, respectively. The final accuracies of photogrammetric reconstructions are on the order of 1 cm and few millimeters for the 2017 and 2018 monitoring campaigns, respectively. This results in realized errors in the comparison of about ± 1 cm. Coordinate variations larger than this magnitude can be reasonably interpreted as coral growth or dissolution. The direct comparison of the two subsequent point clouds is effective in order to evaluate trends in growth and perform morphometric analyses. For highly accurate quantitative assessment of local changes, an expert operator can create and analyze specific 2D profiles that are easily produced from the point clouds.
2020
- Effects of point cloud density, interpolation method and grid size on derived Digital Terrain Model accuracy at micro topography level
[Articolo su rivista]
Aguera-Vega, F.; Aguera-Puntas, M.; Martinez-Carricondo, P.; Mancini, F.; Carvajal, F.
abstract
The objective of this study was to evaluate the effects of the three dimensional (3D) point cloud density derived from Unmanned Aerial Vehicle (UAV) photogrammetry (using Structure from Motion (SfM) and Multi-View Stereopsis (MVS) techniques), the interpolation method for generating a digital terrain model (DTM), and the resolution (grid size (GS)) of the derived DTM on the accuracy of estimated heights in small areas, where a very accurate high spatial resolution is required. A UAV-photogrammetry project was carried out on 13 m × 13 m bare soil with a rotatory wing UAV at 10 m flight altitude (equivalent ground sample distance = 0.4 cm), and the 3D point cloud was derived. A stratified random sample (200 points in each square metre) was extracted and from the rest of the cloud, 15 stratified random samples representing 1, 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, and 90% were extracted. Five replications of each percentage were extracted to analyse the effect of cloud density on DTM accuracy. For each of these 15 × 5 = 75 samples, DTMs were derived using four different interpolation methods (Inverse Distance Weighted (IDW), Multiquadric Radial Basis Function (MRBF), Kriging (KR), and Triangulation with Linear Interpolation (TLI)) and 15 DTM GS values (20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.67, 0.50, and 0.40 cm). Then, 75 × 4 × 15 = 4500 DTMs were analysed. The results showed an optimal GS value for each interpolation method and each density (most of the cases were equal to 1 cm) for which the Root Mean Square Error (RMSE) was the minimum. IDW was the interpolator that yielded the best accuracies for all combinations of densities and GS. Its RMSE when considering the raw cloud was 1.054 cm and increased by 3% when a point cloud with 80% extracted from the raw cloud was used to generate the DTM. When the point cloud included 40% of the raw cloud, RMSE increased by 5%. For densities lower than 15%, RMSE increased exponentially (45% for 1% of raw cloud). The GS minimizing RMSE for densities of 20% or higher was 1 cm, which represents 2.5 times the ground sample distance of the pictures used for developing the photogrammetry project.
2020
- The impact of innovative and emerging technologies on the surveying activities
[Articolo su rivista]
Mancini, Francesco; Piras, Marco; Ruotsalainen, Laura; Vacca, Giuseppina; Lingua, Andrea
abstract
Surveying activities benefit from the continuous and rapid evolution of sensors, methodologies, and processing strategies. Such rapid development influenced the pre-existing geomatics applications in many fields and opened the way to more productive and accurate applications of surveying methodologies. This special issue aims at collecting papers focused on current and/or forthcoming sensors, novel applications and improvements in the surveying practices, and algorithms oriented to the handling of the increasing amount of data produced by automated procedures. Of particular interest is assessing the reliability, performance, precision, and limits for advanced applications in the field of photogrammetry, remote sensing, surveying, and mapping employed in innovative approaches to geomatics. These topics were discussed during the 68th meeting of the Italian Society of Photogrammetry and Survey (SIFET) held in Gaeta, Italy on 20–22 June 2018, and the present special issue includes a number of papers presented during that event.
2020
- Underwater Photogrammetry for Change Detection
[Relazione in Atti di Convegno]
Capra, Alessandro; Castagnetti, Cristina; Mancini, Francesco; Rossi, Paolo
abstract
2020
- Unmanned Aerial System Applications to Coastal Environments
[Capitolo/Saggio]
Mancini, Francesco; Dubbini, Marco
abstract
The objective of this chapter is to acquaint the reader with the potentiality of UAS-based surveys on coastal environments through a discussion of examples available in the very recent literature and through the skills achieved by the authors in this field. After a short introduction on UAV models that can be used to perform aerial surveys and a short description on the available methodologies to process the data acquired by visible and multispectral sensors, the chapter will focus on several UAS applications referred to coastal environments.
2019
- A new methodological approach to assess the stability of discontinuous rocky cliffs using in-situ surveys supported by UAV-based techniques and 3D finite element model: a case study
[Articolo su rivista]
Fazio, N. L.; Perrotti, M.; Andriani, G. F.; Mancini, F.; Rossi, P.; Castagnetti, C.; Lollino, P
abstract
This paper aims to present a new methodological approach for the stability assessment of coastal cliffs constituted of discontinuous rock masses. The method entails in situ specific geostructural and geomechanical surveys, three-dimensional UAV-based Photogrammetric structural models, laboratory geotechnical tests and, two- and three-dimensional finite element analysis (FEM). The application of the method to a case study is then presented and discussed; it regards a 600 m long sea rocky cliff located at Sant'Andrea (Melendugno, South of Apulia, SE Italy) and faced to the southern Adriatic Sea. Here the cliff is made up of an about 15 m-thick sequence of laminate calcisiltites alternate with bioturbated calcarenites belonging to the Uggiano la Chiesa Fm. (Middle-Upper Pliocene).
The structural discontinuities detected with photogrammetry techniques were compared and validated with those derived from conventional in situ survey methods. Later on, the paper discusses assumptions and results of two- and three-dimensional finite element models developed to investigate the potential failure mechanisms of the sea cliff accounting for pre-existing weak planes or discontinuities with unfavourable orientation.
The failure mechanisms obtained by both FEM analysis agree well with those typically observed in the study area.
2019
- Applications of photogrammetry for environmental research (Editorial)
[Articolo su rivista]
Mancini, Francesco; Salvini, Riccardo
abstract
The applications of photogrammetry for environmental research benefits from the continuous and rapid evolution of sensors and methodologies in this field. The support of photogrammetric tools to a very wide range of research activities was previously confined to geomatic disciplines and the methodologies strictly based on terrestrial or traditional aerial photogrammetry. However, the timely investigation of natural or anthropogenic phenomena required more flexible tools and the ability of geoscientists and researchers involved in the study of natural resources to exploit photogrammetric methodologies in a more flexible way. In the last decade, new opportunities came from the possibility to acquire images using low-cost non-metric cameras from low-altitude unmanned aerial vehicles (UAVs), or fixed locations in terrestrial surveys, with a successive highly automated processing strategy. For instance, a huge amount of papers in the recent scientific literature refers to the structure from motion (SfM) technology in the reconstruction of three-dimensional features at very high spatial and temporal resolutions and with a surprisingly high positional accuracy. Point clouds obtained from best practices in novel approaches of close-range photogrammetry has proven to be of compatible spatial resolution and accuracy of those provided by terrestrial laser scanning and, very often, photogrammetry and laser scanning are combined to enhance the qualities of each other. The Special Issue aimed for papers including novelties and advances on the use of recent photogrammetric approaches to a wide range of environmental studies, including the following: photogrammetry for monitoring; UAV photogrammetry for environmental research; photogrammetry for disaster prevention and management; photogrammetry for real-time mapping; merging of data from dierent survey technologies; and novel uses of proximity surveys to geography, geomorphology, geotechnologies, landscape description, coastal studies, archaeology, etc.
2019
- Dynamic Assessment of Masonry Towers Based on Terrestrial Radar Interferometer and Accelerometers
[Articolo su rivista]
Castagnetti, Cristina; Bassoli, Elisa; Vincenzi, Loris; Mancini, Francesco
abstract
This paper discusses the performance of a terrestrial radar interferometer for the structural monitoring of ancient masonry towers. High-speed radar interferometry is an innovative and powerful remote sensing technique for the dynamic monitoring of large structures since it is contactless, non-destructive, and able to measure fast displacements on the order of tenths of millimeters. This methodology was tested on a masonry tower of great historical interest, the Saint Prospero bell tower (Northern Italy). To evaluate the quality of the results, data collected from the interferometer were compared and validated with those provided by two types of accelerometer-based measuring systems directly installed on the tower. Dynamic tests were conducted in operational conditions as well as during a bell concert. The first aimed at characterizing the dynamic behavior of the tower, while the second allowed to evaluate the bell swinging effects. Results showed a good agreement among the different measuring systems and demonstrated the potential of the radar interferometry for the dynamic monitoring of structures, with special focus on the need for an accurate design of the geometric aspects of the surveys.
2019
- Dynamic monitoring and evaluation of bell ringing effects for the structural assessment of a masonry bell tower
[Articolo su rivista]
Vincenzi, L; Bassoli, E; Ponsi, Federico; Castagnetti, C; Mancini, F
abstract
The paper presents a rational procedure for the structural assessment of bell towers with respect to the dynamic actions induced by the bell ringing, based on structural monitoring and data processing. This methodology is tested on the bell tower of Saint Prospero (Reggio Emilia, Northern Italy), a masonry tower of great historical interest. The procedure includes an accurate geometrical survey for a deep knowledge of the structural geometry, which is the base for the structural modelling. A finite element model of the tower is calibrated with respect to the modal properties evaluated from the structural response measured in operational conditions. The structural response of the tower was also measured during a famous cultural event held in the city centre of Reggio Emilia, when skilled bell ringers played traditional melodies. The tower displacements are evaluated applying a double integration technique and a detrending procedure based on the empirical mode decomposition to the acquired accelerations. To simulate the structural response to the bell ringing, the tower and the bell are modelled as a single degree of freedom system and an unforced and undamped simple pendulum, respectively. For safety assessment purposes, the structural response of the tower is evaluated considering different oscillation angles in order to identify the one causing the maximum displacement. Finally, the stress pattern of the masonry caused by the bell-induced displacement is estimated thanks to the calibrated finite element model of the tower. Results show that the bell ringing causes a stress pattern lower than the allowable masonry strength for the serviceability conditions.
2019
- High accuracy underwater photogrammetric surveying
[Relazione in Atti di Convegno]
Capra, A.; Castagnetti, C.; Dubbini, M.; Gruen, A.; Guo, T.; Mancini, F.; Neyer, F.; Rossi, P.; Troyer, M.
abstract
The evolution of underwater photogrammetry allows to realize 3D models of submerged object and structures throughout the use of rapid and efficient procedures either in terms of data acquisition and data processing. These procedures are based on solutions that are applied using natural control points, signalized markers and tie points; the most common algorithms are based on Structure from Motion (SfM) approach. The limit of these applications is sometimes due to the final accuracy, especially when the goal is a centimeter level of accuracy. This accuracy should be necessary when dealing with a survey devoted to deformation control purposes. An example is the underwater photogrammetry for the determination of coral growth; it is effectively a movement or a deformation detection issue where the geometric change is almost at centimeter or few centimeters accuracy level. When dealing with deformation control applications, a geodetic network is essential to realize a stable and unambiguous reference frame through the accurate and permanent installation of Ground Control Points (GCPs). Such a network, indeed, permits a robust reference frame for the georeferencing of images blocks in the different époques of data acquisition. Therefore, the comparison among subsequent photogrammetric restitutions is based on homogeneous 3D models that have been oriented in the same absolute reference system. The photogrammetric survey is based on a methodological approach especially adapted to underwater biometry (like coral growth determination) and to underwater archaeology. The approach is suitable both for modeling objects of relatively reduced dimensions and for structures with a length of ten meters or more, such as coral barriers, wrecks and long walls. The paper describes underwater photogrammetric surveys on sites at different extensions, the geodetic GCPs reference network installation and measurements (distance and elevation difference observations) as well as preliminary results of the network adjustment. A brief description of image acquisition at a different scales and the resulting 3D model of first campaign are also shown.
2019
- Monitoraggio di strutture storiche mediante interferometria radar terrestre
[Relazione in Atti di Convegno]
Bassoli, Elisa; Ponsi, Federico; Castagnetti, Cristina; Mancini, Francesco; Vincenzi, Loris
abstract
In questa memoria vengono discusse le prestazioni, i vantaggi e gli svantaggi dell’interferometria radar terrestre con antenna ad apertura reale (TInRAR) per il monitoraggio strutturale degli edifici esistenti e storici. L’interferometro radar terrestre è in grado di rilevare spostamenti differenziali confrontando la fase del segnale radar raccolto e riflesso dalla struttura rispetto a quella del segnale trasmesso. Gli spostamenti lungo la linea di vista (LoS) che si possono misurare sono dell’ordine del centesimo di millimetro e le misure possono essere campionate con frequenza fino a 200 Hz. La memoria riporta i test dinamici effettuati sulla torre campanaria della Basilica di San Prospero a Reggio Emilia (Italia), confrontando gli spostamenti misurati dal radar terrestre con i valori ottenuti per doppia integrazione delle accelerazioni misurate da accelerometri installati direttamente sulla struttura. Grazie alla capacità di misurare in maniera continua e diretta gli spostamenti di numerosi punti della struttura, l’uso della strumentazione TInRAR integrata alla strumentazione tradizionale potrebbe essere di grande ausilio nell’interpretazione del comportamento strutturale e nella valutazione della progressione di un potenziale danneggiamento nelle strutture a seguito di eventi sismici.
2019
- POTENZIALITÀ E PROBLEMATICHE NELL’UTILIZZO DELLA FOTOGRAMMETRIA SUBACQUEA PER LA MISURA DELL’ACCRESCIMENTO DI COLONIE CORALLIGENE
[EVALUATION OF UNDERWATER PHOTOGRAMMETRY’ PERFORMANCES IN THE ASSESSMENT OF CORAL REEF 3D CHANGES]
[Articolo su rivista]
Rossi, P.; Castagnetti, C.; Capra, A.; Brooks, A. J.; Mancini, F.
abstract
This paper presents a multi-temporal underwater photogrammetric survey of a reef patch located in Moorea Island (French Polynesia) to detect a coral growth at a required level of accuracy of 10-15 mmyears. An approach based on processing of underwater imagery by the well-known Structure from Motion method and ground control points derived from the adjustment of underwater topographic measurements allowed the three-dimensional quantification of ecological characteristic at patch scale and an assessment of the reef growth and its structural complexity. To guarantee the repeatability of surveys over time at required level of accuracy and spatial resolution, the paper introduces issues related to reference frame, network adjustment and design of photogrammetric surveying. Measuring tools and reference points were properly designed and presented by the authors. The network adjustment performed after measuring distances and height differences, provided an average precision of 1.2 mm and 2.9 mm in the horizontal and vertical component respectively. The final positional precision of photogrammetric reconstructions was in the order of 1 centimeter and few millimeters for 2017 and 2018 monitoring campaigns respectively. Then, the accuracy of the comparison resulted of about 1 cm which represents a factor to be considered in the successive interpretations of coral growth or dissolution phenomena. The direct comparison of the two subsequent point clouds is effective in the evaluation of growth rates and in the successive morphometric analyses. For highly accurate quantitative assessment of local changes, an expert operator can create and analyze specific 2D profiles that easily come from the point clouds.
2019
- Sentinel-1 data for ground deformation monitoring: the SNAP-StaMPS workflow
[Relazione in Atti di Convegno]
Grassi, Francesca; Mancini, Francesco
abstract
During the last decades, radar interferometry has become an effective technique able to provide reliable
information in a variety of applications such as geodesy, natural hazards assessment, ground deformations and monitoring. With the beginning of Copernicus Earth Observation program, new chances in Earth Observation field arose. For instance, Sentinel-1A and -1B provide synthetic aperture radar acquisitions over very large areas at average spatial resolution and very short revisit time, thus increasing the opportunities offered by existing radar satellite. In this work we assess the potentialities of Sentinel-1 data by the generation of displacements maps through the PSInSAR techniques and a processing workflow including the free Sentinel Application Platform (SNAP) and Stanford Method for Persistent Scatterers (StaMPS) software package. Results are referred to a couple of areas affected by ground deformation.
2019
- Virtual reconstruction of damaged archaeological sites based on Unmanned Aerial Vehicle Photogrammetry and 3D modelling. Study case of a southeastern Iberia production area in the Bronze Age
[Articolo su rivista]
Carvajal-Ramírez, F.; Navarro-Ortega, A. D.; Agüera-Vega, F.; Martínez-Carricondo, P.; Mancini, F.
abstract
Knowledge about cultural and archaeological heritage can dissolve or even disappear with the passage of time, especially when the protection level of the archaeological site is weak. The recent development of techniques based on remote sensing from remotely controlled light platforms, so-called Unmanned Aerial Vehicles (UAV) or drones, carrying sensors in visible and other spectral ranges, allows to measure efficiently the current surface morphology of a damaged archaeological site.
In this work, a deteriorated and unique archaeological site due its chronological and functional singularity was chosen as the study case. Mound structures made of stone, interconnected one to each other in a regular network, covered by vaults, and well adapted to a smooth slope topography have no known precedents in the Iberian Peninsula in the Bronze Age. Nowadays, this site is seriously damaged, and its protection level by the administrations is weak. Nevertheless, two archaeological campaigns were carried out recording interesting information.
A UAV-Photogrammetry project based on Structure from Motion (SfM) and Multi-View Stereopsis (MVS) algorithms was applied to model the surface terrain where the structural basis and connection channels were built, obtaining a dense point cloud, an orthoimage and a Digital Surface Model (DSM). The topographic data covering altered areas were removed from the dense point cloud, and then a new interpolated surface was obtained representing the unaltered morphology.
Finally, the information recorded in the archaeological campaigns was materialised in a virtual reconstruction located between both surfaces, measured by UAV-Photogrammetry and interpolated, and then the original architectural complex in its context was recreated and shared with the scientific community through Google Earth, contributing to recovering and preserving this cultural heritage, even after its disappearance.
2018
- New geodetic and gravimetric maps to infer geodynamics of Antarctica with insights on Victoria Land
[Articolo su rivista]
Zanutta, Antonio; Negusini, Monia; Vittuari, Luca; Martelli, Leonardo; Cianfarra, Paola; Salvini, Francesco; Mancini, Francesco; Sterzai, Paolo; Dubbini, Marco; Capra, Alessandro
abstract
In order to make inferences on the geodynamics of Antarctica, geodetic and gravimetric maps derived from past and new observations can be used. This paper provides new insights into the geodynamics of Antarctica by integrating data at regional and continental scales. In particular, signatures of geodynamic activity at a regional extent have been investigated in Victoria Land (VL, Antarctica) by means of Global Navigation Satellite System (GNSS) permanent station observations, data from the VLNDEF (Victoria Land Network for Deformation control) discontinuous network, and gravity station measurements. At the continental scale, episodic GNSS observations on VLNDEF sites collected for 20 years, together with continuous data from the International GNSS Service (IGS) and Polar Earth Observing Network (POLENET) sites, were processed, and the Euler pole position assessed with the angular velocity of the Antarctic plate. Both the Bouguer and the free-air gravity anomaly maps were obtained by integrating the available open-access geophysics dataset, and a compilation of 180 gravity measurements collected in the VL within the Italian National Program for Antarctic Research (PNRA) activities. As a result, new evidence has been detected at regional and continental scale. The main absolute motion of VL is towards SE (Ve 9.9 ± 0.26 mm/yr, Vn −11.9 ± 0.27 mm/yr) with a pattern similar to the transforms of the Tasman and Balleny fracture zones produced as consequence of Southern Ocean spreading. Residual velocities of the GNSS stations located in VL confirm the active role of the two main tectonic lineaments of the region, the Rennick–Aviator and the Lillie–Tucker faults with right-lateral sense of shear. The resulting VL gravity anomalies show a NW region characterized by small sized Bouguer anomaly with high uplift rates associated and a SE region with low values of Bouguer anomaly and general subsidence phenomena. The East and West Antarctica are characterized by a different thickness of the Earth’s crust, and the relative velocities obtained by the observed GNSS data confirm that movements between the two regions are negligible. In East Antarctica, the roots of the main subglacial highlands, Gamburtsev Mts and Dronning Maud Land, are present. The Northern Victoria Land (NVL) is characterized by more scattered anomalies. These confirm the differences between the Glacial Isostatic Adjustment (GIA) modeled and observed uplift rates that could be related to deep-seated, regional scale structures.
2017
- An Integrated Procedure to Assess the Stability of Coastal Rocky Cliffs: From UAV Close-Range Photogrammetry to Geomechanical Finite Element Modeling
[Articolo su rivista]
Mancini, Francesco; Castagnetti, Cristina; Rossi, Paolo; Dubbini, Marco; Fazio, Nunzio Luciano; Perrotti, Michele; Lollino, Piernicola
abstract
The present paper explores the combination of unmanned aerial vehicle (UAV) photogrammetry and three-dimensional geomechanical modeling in the investigation of instability processes of long sectors of coastal rocky cliffs. The need of a reliable and detailed reconstruction of the geometry of the cliff surfaces, beside the geomechanical characterization of the rock materials, could represent a very challenging requirement for sub-vertical coastal cliffs overlooking the sea. Very often, no information could be acquired by alternative surveying methodologies, due to the absence of vantage points, and the fieldwork could pose a risk for personnel. The case study is represented by a 600 m long sea cliff located at Sant’Andrea (Melendugno, Apulia, Italy). The cliff is characterized by a very complex geometrical setting, with a suggestive alternation of 10 to 20 m high vertical walls, with frequent caves, arches and rock-stacks. Initially, the rocky cliff surface was reconstructed at very fine spatial resolution from the combination of nadir and oblique images acquired by unmanned aerial vehicles. Successively, a limited area has been selected for further investigation. In particular, data refinement/decimation procedure has been assessed to find a convenient three-dimensional model to be used in the finite element geomechanical modeling without loss of information on the surface complexity. Finally, to test integrated procedure, the potential modes of failure of such sector of the investigated cliff were achieved. Results indicate that the most likely failure mechanism along the sea cliff examined is represented by the possible propagation of shear fractures or tensile failures along concave cliff portions or over-hanging due to previous collapses or erosion of the underlying rock volumes. The proposed approach to the investigation of coastal cliff stability has proven to be a possible and flexible tool in the rapid and highly-automated investigation of hazards to slope failure in coastal areas.
2017
- Assessing the relationship between sky view factor and land surface temperature to the spatial resolution
[Articolo su rivista]
Scarano, M; Mancini, F.
abstract
This article compares the land surface temperature (LST) and sky view factor (SVF) as indicator of the impact of urban morphology on the urban heat island effect. For this purpose, the work investigates the dependence of this relationship to spatial resolutions varying from coarse to very fine and related scaling effect. For this purpose, several daytime Landsat 8, Advanced Spaceborne Thermal Emission and Reflection Radiometer and airborne TASI-600 images acquired in different months of the year were used to retrieve LST. Moreover, a three-dimensional building vector database was used to produce SVF maps at different spatial resolutions, according to the thermal ones. The results show a positive relationship between LST and SVF; these trends are almost superimposable for same-sensor images, but vary for images at different resolutions. This is likely due to the interference on the SVF and LST values of micro-scale factors, e.g. thermal properties of building materials, anthropogenic heat, humidity and pollutants, and others, which in a macro-scale analysis are smoothed becoming irrelevant. Therefore, a digital database able to represent urban features at suitable spatial scale is a requirement for a reliable analysis. In particular, when airborne thermal data are used, the lack of a reliable cartographic digital data could represent a limiting factor. Specifically, the data set used in the computation of SVF and other geographical parameters involved in the LST assessment should be consistent with the resolution of airborne thermal data.
2017
- Combining nadir and oblique UAV imagery to reconstruct quarry topography: methodology and feasibility analysis
[Articolo su rivista]
Rossi, Paolo; Mancini, Francesco; Dubbini, Marco; Mazzone, Francesco; Capra, Alessandro
abstract
The feasibility of unmanned-aerial-vehicle-based photogrammetry was assessed for the reconstruction of high-resolution topography and geomorphic features of quarries by nadir and off-nadir imagery. The test site was a quarry located in the rural area of Turi (Bari, southern Italy). Two processing scenarios were created. Nadir images were initially used, and images acquired with off-nadir angles were added. An accurate set of ground control points (GCPs) were surveyed for both georeferencing purposes and validation processes. In the reconstruction of the surfaces, an accuracy of a few centimeters was achieved in the final positioning of point clouds representing the main geometries of quarry environment. However, greatest differences were found along the edges or the lines characterized by sudden slope changes. To better understand such results, some characteristic quarry shapes depicted by both the scenarios were compared to those surveyed by a total station used as an independent benchmark technique. It allowed to define the benefits introduced by the joint use of nadir and oblique images in the delineation of quarry shapes, surface discontinuities and better descriptions of sub-vertical walls. Beside the evaluation of benefits introduced by use of oblique cameras, the effectiveness of the proposed methodology was also discussed with alternative technologies. Unmanned aerial platforms represent an effective solution, with the need for few accurate GCPs.
2017
- Monitoring geodynamic activity in the Victoria Land, East Antarctica: evidence from GNSS measurements
[Articolo su rivista]
Zanutta, A; Negusini, M; Vittuari, L; Cianfarra, P; Salvini, F; Mancini, F; Sterzai, P; Dubbini, M; Galeandro, A; Capra, A.
abstract
GNSS networks in Antarctica are a fundamental tool to define actual crustal displacements due to geological and geophysical processes and to constrain the glacial isostatic models (GIA). A large network devoted to the detection and monitoring of crustal deformations in the Northern Victoria Land (Victoria Land Network for DEFormation control – VLNDEF), was monumented during the 1999–2000 and 2000–2001 field campaigns, as part of Italian National Program for Antarctic Research and surveyed periodically during the Southern summer seasons.
In this paper, GPS observations of VLNDEF collected over a more than 15-year span, together with various selected POLENET sites and more than 70 IGS stations, were processed with Bernese Software, using a classical double difference approach. A solution was obtained combining NEQs by means of ADDNEQ2/FODITS tools embedded in Bernese Software. All the Antarctic sites were kept free and a subset of 50 IGS stations were used to frame VLNDEF into ITRF2008. New evidence provided by analysis of GPS time series for the VLNDEF network is presented; also displacements along the vertical component are compared with the recently published GIA models. The absolute velocities indicate an overall displacement of the northern Victoria Land region along the south-east direction (Ve = 10.6 mm/yr, Vn = −11.5 mm/yr) and an average uplift rate of Vu = 0.5 mm/yr. Two GIA models have been analyzed: ICE-6G_C-VM5a proposed by Argus et al. (2014), Peltier et al. (2015) and W12A_v1 by Whitehouse et al. (2012a,b). Up rates, predicted over the VLNDEF sites by the mentioned GIA models, have been extracted and compared with those observed. A preliminary comparison with GPS-derived vertical rates shows that the Victoria Land ICE-6G_C-VM5 and W12A_v1 GIA models predict overestimated uplift rates of 0.7 and 0.9 mm/yr weighted mean residuals respectively. The mean horizontal relative motions within the Victoria Land (VL) area are in most cases negligible, while only a few points exhibit horizontal velocities greater than the confidence level. Such a residual horizontal velocity field could represent some of the tectonic characteristics affecting VL, characterized by block faulting, tilting along NE striking and SE dipping extensional faults. Uplift rates, highlighted in the present paper depict a well defined spatial pattern in the investigated areas. Northward, all sites show a general positive trend up to 2.3 mm/yr. In the central and southern areas small negative trends (up to −1.3 mm/yr) were detected in the vertical displacements. Only the site VL06, located atop the Mt. Melbourne volcano, does not concord with such a general reading, as it is representative of the volcanic complex’s evolution. Observed and predicted uplift rates increase westward (inland) where the ice-load increases. The same behavior is predicted southward by the GIA models; whereas GPS values decrease toward the south pole, due to the movements of a few sites reflecting the neotectonic phenomena acting in the Victoria Land region.
2016
- Achievement of the “benchmark” session - on the use of UAV images for 3D reconstruction: a joint experience among users” (held during the 61th SIFET meeting, Lecce, Italy, june 8-10, 2016)
[Articolo su rivista]
Mancini, Francesco; Castagnetti, Cristina; Rossi, Paolo; Altri, Autori
abstract
This paper summarize the achievements of an experimental meeting session held within the 61th SIFET national meeting (Lecce, Italy, 6-10 June 2016). The session named “benchmark” introduced results achieved by users in the processing of a shared dataset, composed of images acquired from unmanned aerial vehicle (UAV), to reconstruct the three-dimensional properties of cultural heritage. Data, results provided by authors and validation strategies of outcomes from the photogrammetric processing of UAV images highlighted different level of spatial accuracy by the products. Despite the good level of automation introduced by the structure from motion approach to data processing, the users detected differences at cm-level in the accuracy of results after the use of available software. ITA: Il lavoro riassume i risultati ottenuti da diversi partecipanti alla sessione “benchmark” - uso di immagini UAV per la ricostruzione 3D: esperienze condivise tra utenti, svoltasi nell’ambito del 61° convegno nazionale SIFET (Lecce 8-10 giugno 2016). L’iniziativa ha previsto l’elaborazione di un dataset comune, rappresentato da immagini acquisite tramite aeromobile a pilotaggio remoto, ai fini della ricostruzione tridimensionale di ambienti di pregio storico e culturale. Tra gli obiettivi principali vi era quello di confrontare i diversi approcci seguiti dai partecipanti nell’elaborazione dei dati, mettendo in luce le diverse potenzialità dei software disponibili, le possibili strategie relative all’uso dei punti di controllo e il livello di accuratezza raggiunto. Nonostante l’utilizzo di procedure consolidate nell’analisi dei dati, i risultati riportati dagli utenti evidenziano significative differenze nei livelli di accuratezza, verificabili dopo il confronto con i punti di controllo e con la nuvola di punti ottenuta con scansione laser terrestre.
2016
- POTENTIALITY OF THE NEW WEARABLE SYSTEMS FOR 3D SCANNING AN EXPERIMENTATION OF PEGASUS BACKPACK BY LEICAGEOSYSTEMS PRESSO AT THE DUCAL PALACE OF MODENA
[Articolo su rivista]
Castagnetti, Cristina; Mancini, Francesco; Rivola, Riccardo; Rossi, Paolo; Oppici, Simone; Albano, Valentina; Fiorentini, Marco
abstract
The terrestrial laser scanning is a well established technology for a wide range of applications. Recently the development of wearable systems based on multiple profilers and cameras opens to new challenging field of applications. The potentialities of such systems in terms of accuracy, productivity, completeness of the final dataset has been tested and described in the paper. The case study is provided by the Military Academy of Modena where an expeditious survey was carried out both in internal and external environments with the objective of evaluating the performance of the Leica Pegasus Backpack, a wearable system, in comparison with the Leica ScanStation C10, a traditional terrestrial laser scanner in static position. The field test allows to highlight the most suitable applications for these wearable systems.
2016
- Rapporto sulla sessione “benchmark” - uso di immagini UAV per la ricostruzione 3D: esperienze condivise tra utenti
[Articolo su rivista]
Mancini, Francesco
abstract
Il rapporto introduce una nuova attività condotta nell’ambito del 61° convegno nazionale SIFET (Lecce 6-10 Giugno 2016). Il convegno ha previsto una sessione denominata “benchmark” nella quale sono stati illustrati i risultati ottenuti da diversi utenti nell’elaborazione di un dataset comune, rappresentato da immagini acquisite tramite UAV, ai fini della ricostruzione tridimensionale di ambienti di pregio storico e culturale. Durante la sessione sono stati illustrati e confrontati i risultati ottenuti dagli utenti che hanno aderito all’iniziativa, mettendo in luce le diverse strategie scelte nell’elaborazione dei dati e il livello di accuratezza raggiunto. Tali risultati saranno oggetto di relazione specifiche da parte degli utenti che hanno aderito all’iniziativa.
2015
- 3D reconstruction of an underwater archaelogical site: comparison between low cost cameras
[Relazione in Atti di Convegno]
Capra, Alessandro; Dubbini, M; Bertacchini, Eleonora; Castagnetti, Cristina; Mancini, Francesco
abstract
The 3D reconstruction with a metric content of a submerged area, where objects and structures of archaeological interest are found, could play an important role in the research and study activities and even in the digitization of the cultural heritage. The reconstruction of 3D object, of interest for archaeologists, constitutes a starting point in the classification and description of object in digital format and for successive fruition by user after delivering through several media. The starting point is a metric evaluation of the site obtained with photogrammetric surveying and appropriate 3D restitution. The authors have been applying the underwater photogrammetric technique since several years using underwater digital cameras and, in this paper, digital low cost cameras (off-the-shelf). Results of tests made on submerged objects with three cameras are presented: (c) Canon Power Shot G12, (c) Intova Sport HD e (c) GoPro HERO 2. The experimentation had the goal to evaluate the precision in self-calibration procedures, essential for multimedia underwater photogrammetry, and to analyze the quality of 3D restitution. Precisions obtained in the calibration and orientation procedures was assessed by using three cameras, and an homogeneous set control points. Data were processed with (c) Agisoft Photoscan. Successively, 3D models were created and the comparison of the models derived from the use of different cameras was performed. Different potentialities of the used cameras are reported in the discussion section. The 3D restitution of objects and structures was integrated with sea bottom floor morphology in order to achieve a comprehensive description of the site. A possible methodology of survey and representation of submerged objects is therefore illustrated, considering an automatic and a semi-automatic approach.
2015
- Application of SLEUTH Model to Predict Urbanization Along the Emilia-Romagna Coast (Italy): Considerations and Lessons Learned
[Relazione in Atti di Convegno]
Sekovski, I; Mancini, Francesco; Stecchi, F.
abstract
Coastal zone of Emilia-Romagna region, Italy, has been significantly urbanized during the last decades, as a result of a tourism development. This was the main motivation to estimate future trajectories of urban growth in the area. Cellular automata (CA)-based SLEUTH model was applied for this purpose, by using quality geographical dataset combined with relevant information on environmental management policy. Three different scenarios of urban growth were employed: sprawled growth scenario, compact growth scenario and a scenario with business-as-usual pattern of development. The results showed the maximum increase in urbanization in the area would occur if urban areas continue to grow according to compact growth scenario, while minimum was observed in case of more sprawled-like type of growth. This research goes beyond the domain of the study site, providing future users of SLEUTH detailed discussion on considerations that need to be taken into account in its application
2015
- Contribution of Geomatics Engineering and VGI Within the Landslide Risk Assessment Procedures
[Relazione in Atti di Convegno]
Mancini, Francesco; Capra, Alessandro; Castagnetti, Cristina; Ceppi, C; Bertacchini, Eleonora; Rivola, Riccardo
abstract
This paper presents a literature review on the methodology called Volunteered Geographic Information (VGI) and its use for Landslide Risk Assessment (LRA). General risk assessment procedures are discussed and the potential contributions of VGI are identified, in particular when quantitative characterization of factors such as Hazard, Vulnerability and Exposure is required. The review shows that the standard LRA procedures may benefit from input given by surveyors when performing hazard assessments, while crowdsourced data would be a valuable support in vulnerability/damage assessment studies. The review also highlights several limitations related to the role of VGI and crowdsourcing in LRA.
2015
- Coupling scenarios of urban growth and flood hazard along the Emilia-Romagna coast (Italy)
[Articolo su rivista]
Sekovski, I; Armaroli, C; Calabrese, L; Mancini, Francesco; Stecchi, F; Perini, L.
abstract
The extent of coastline urbanization reduces their resilience to flooding, especially in low lying areas. The study site is the Emilia-Romagna Region coastline (Italy), historically affected by marine storms and floods. The main aim of this study is to investigate the vulnerability of this coastal area to marine flooding by considering the dynamics of the forcing component (Total Water Level) and the dynamics of the receptor (urban areas). This was done by comparing the output of the three flooding scenarios (10, 100 and >100 year return periods) to the output of different scenarios of future urban growth up to 2050. Scenario-based marine flooding extents were derived by applying the Cost-Distance tool of ArcGIS® to a high resolution Digital Terrain Model. Three scenarios of urban growth (similar-as-historic, compact and sprawled) up to 2050 were estimated by applying the cellular automata based SLEUTH model. The results show that, if the urban growth is compact-like, flood-prone areas will largely increase with respect to similar-as-historic and sprawled growth scenarios. Combining the two methodologies can be useful for identify flood-prone areas that have a high potential for future urbanization, and is therefore crucial for coastal managers and planners.
2015
- Ionospheric activity and possible connection with seismicity: Contribution from the analysis of long time series of GNSS signals
[Articolo su rivista]
Mancini, Francesco; Galeandro, Angelo; De Giglio, Michaela; Barbarella, Maurizio
abstract
The modifications of some atmospheric physical properties prior to a high magnitude earthquake were debated in the frame of the Lithosphere Atmosphere Ionosphere Coupling (LAIC) model. In this work, among the variety of involved phenomena, the ionisation of air at the ionospheric levels triggered by the leaking of gases from the Earth’s crust was investigated through the analysis of GNSS (Global Navigation Satellite System) signals. In particular, the authors analysed a 5 year (2008–2012) long series of GNSS based ionospheric TEC to produce maps over an area surrounding the epicentre of the L’Aquila (Italy, Mw = 6.3) earthquake of April 6th, 2009. The series was used to detect and quantify amplitude
and duration of episodes of ionospheric disturbances by a statistical approach and to discriminate local and global effects on the ionosphere comparing these series with TEC values provided by the analysis of GNSS data from international permanent trackers distributed over a wider region. The study found that during this time interval only three statistically meaningful episodes of ionospheric disturbances were observed. One of them, occurring during the night of 16th of March 2009, anticipated the main shock by 3 weeks and could be connected with the strong earthquake of 6th of April. The other two significant episodes were detected within periods that were not close to the main seismic events and are more likely due to various and global reasons.
2015
- UAV Surveys for Representing and Document the Cultural Heritage
[Relazione in Atti di Convegno]
Caprioli, M; Mancini, Francesco; Mazzone, F; Scarano, M; Trizzino, R.
abstract
The new survey techniques allow for a more detailed depiction of the characteristics of the cultural heritage of which our country is so rich. Unmanned Aerial Vehicles (UAV) are emerging as a key engineering tool for future environmental survey tasks. UAV aerial imagery offers both timely (on demand) and more detailed (higher resolution) information than comparable satellite imagery. In the present study the opportunities of obtaining more detailed documentation of cultural goods throughout UAV survey have been investigated.The survey was conducted on an ancient Aragonese watchtower of the seventeenth century, located near the Abbey of San Vito in the countryside of Polignano a Mare (in the province of Bari, Southern Italy) (Fig.1). The high resolution of the produced images, approximately 1 cm x pixels, allows to obtain all elements of both structural and qualitative information required for a conservative restoration project of the monument. The peculiarity of the transportation vehicle of the camera has also made it possible to detect the top surface of the roof covering of the building, normally not accessible, with the presence of a chimney and an access hatch, on which to intervene for the proper disposal of rainwater. The research refers to the metric characteristics, accuracy, level of detail, the particular crack patterns, etc., reachable by photogrammetric methods, with the help of dedicated software (Agisoft PhotoScan) such as Computer Vision methodologies.
2014
- Assessing ionospheric activity from GNSS measurements as a possible precursor of high magnitude earthquakes
[Relazione in Atti di Convegno]
Ceppi, C; Galeandro, A; Mancini, Francesco; Tarantino, E.
abstract
The Lithosphere-Atmosphere-Ionosphere Coupling model provides for the modification of atmospheric physical properties prior to a high magnitude
earthquake over an area near to the epicentre. Ionization of air, caused by possible radon leaking from earth crust, could be one of the causes.
In the GNSS (Global Navigation Satellite System) sciences, disturbances of ionospheric activity can be investigated through the analysis of refraction
phenomena occurring on the signal along the path satellite-to-receiver and maps representing the ionospheric activity as Total Electron Content could be drawn. By a 6 month long series of GNSS data, we investigated ionospheric disturbances related to the M=6.3 earthquake occurred at L’Aquila (Italy) on 6th of April 2009. Resulting TEC maps exhibit meaningful anomalies 3 weeks before the main shock.
2014
- Estrazione di linee di riva mediante classificazione multispettrale di immagini satellitari ad alta risoluzione
[Relazione in Atti di Convegno]
Sekovski, I; Stecchi, F; Mancini, F; Gabbianelli, G
abstract
La linea di riva rappresenta un elemento costiero dinamico e complesso, spesso difficilmente distinguibile, la cui identificazione precisa è ancora un tema aperto per gli esperti del settore. Il principale scopo di questo lavoro è di valutare il potenziale di un approccio semiautomatico di estrazione di linee di riva, mediante analisi multispettrali di immagini satellitari ad alta risoluzione.
L’analisi è stata effettuata utilizzando un’immagine WorldView-2 relativa a circa 40 km di costa lungo il litorale Ravennate, nel Nord Adriatico. Da decenni questo tratto di costa è interessato da significativi arretramenti della linea di riva e fenomeni di erosione in genere, dovuti principalmente a ridotti apporti sedimentari di origine fluviale, subsidenza, storm surges e opere di difesa inefficaci.
Mediante classificazioni multispettrali delle diverse coperture del suolo lungo la fascia costiera, è stato possibile identificare la linea di separazione tra sabbia asciutta e sabbia bagnata. Le oscillazioni di marea sono state prese in considerazione al fine di valutare i possibili scostamenti dal livello medio mare. Sono state applicate tecniche di classificazione unsupervised (ISODATA) e supervised (Parallelepiped, Gaussian maximum likelihood, Minimum-distance-to-means and Mahalanobis distance). Al fine di valutare l’affidabilità di questi metodi per l’estrazione della linea di riva, sono state calcolate le distanze medie tra le varie linee ottenute ed una linea di riferimento digitalizzata manualmente dall’utente. I valori della mediana della distanze non superano i 6 m, e per alcune classificazioni come ISODATA e Mahalanobis sono di circa 2 m, indicando un alto grado di compatibilità tra la linea di riferimento e quelle calcolate.
Inoltre la correlazione tra i diversi valori di scostamento e le tipologie di costa presenti, ha evidenziato l’influenza di particolari elementi geomorfologici e delle opere di difesa. I risultati indicano come gli ambienti costieri più omogenei ed antropizzati siano facilmente classificabili, al contrario di ambienti più naturali, eterogenei e discontinui.
L’elevata congruenza tra la linea di riferimento e le linee derivanti dalle classificazioni, suggerisce un possibile utilizzo di questo metodo di estrazione della linea di riva per attività di monitoraggio costiero. La procedura di analisi semiautomatica permette un risparmio considerevole di tempi e costi. Inoltre, rispetto alla digitalizzazione manuale, il livello di soggettività nell’identificazione della line di riva è sensibilmente ridotto.
2014
- Image classification methods applied to shoreline extraction on very high-resolution multispectral imagery
[Articolo su rivista]
Sekovski, I; Stecchi, F; Mancini, Francesco; Del Rio, L.
abstract
Comprehension of vulnerability to coastal erosion in dynamic coastal environments strongly depends on accurate and frequent detection of shoreline position. The monitoring of such environments could benefit from the semi-automatic shoreline delineation method, especially in terms of time, cost, and labour-intensiveness. This article explores the potential of using a semi-automatic approach in delineating a proxy-based shoreline by processing high-resolution multispectral WorldView-2 satellite imagery. We studied the potential and differences of basic and easily accessible standard classification methods for shoreline detection. In particular we explored the use of
high spatial and spectral resolution satellite imagery for shoreline extraction. The case study was carried out on a 40 km coastal stretch facing the Northern Adriatic Sea (Italy) and belonging to the Municipality of Ravenna. In this area a frequent monitoring of shoreline position is required because of the extreme vulnerability to erosion phenomena that have resulted in a general trend of coastal retreat over recent decades. The wet/dry shorelines were delineated between the classes of wet and dry sand, resulting from different supervised (Parallelepiped, Gaussian Maximum Likelihood, Minimum-Distance-to-Means, and Mahalanobis distance) image classification techniques and the unsupervised Iterative Self-Organizing Data Analysis Technique (ISODATA). In order to assign reliability to outcomes, the extrapolated shorelines were compared to reference shorelines visually identified by an expert, by assessing the average mean distance between them. In addition, the correlation between offset rates and different types of coast was investigated to examine the influence of specific coastal features on shoreline extraction capability. The results highlighted a high level of compatibility. The average median distance between reference shorelines and those
resulting from the classification methods was less than 5.6 m (Maximum likelihood), whereas a valuable distance of just 2.2 m was detected from ISODATA and Mahalanobis. Heterogeneous coastal stretches exhibited a larger offset between extracted and reference shorelines than the homogeneous ones. To finally evaluate the coastal evolution of the area, results from Mahalanobis classification were compared to a shoreline derived from airborne light detection and ranging (lidar) data. The fine spatial resolution provided by both methodologies allowed a detailed Digital Shoreline Analysis System (DSAS) comparison, detecting an erosive trend within a wide portion of the study area.
2013
- Disturbi indotti da attività ionosferica eccezionale sulle soluzioni GNSS
[Relazione in Atti di Convegno]
Mancini, Francesco; Galeandro, A.
abstract
La ionosfera rappresenta una fonte di disturbo che, se non ben modellizzata, può introdurre errori di entità non trascurabile nel posizionamento GNSS. L'attività ionosferica è fortemente influenzata dall'attività solare, che presenta diverse ciclicità, tra cui quella principale con periodicità undecennale, misurabile attraverso il numero di macchie solari (sunspot number). In base a tali informazioni è possibile apprezzare il repentino incremento dell’attività solare che si sta verificando a partire dal 2010, con picchi massimi attesi nel corso del 2013. Anche se i più accurati metodi di posizionamento satellitare, relativi e NRTK, modellizzano gli effetti ionosferici sulle osservabili, gli effetti indotti da eventi di entità eccezionale o corrispondenti alla massima attività solare, non sono del tutto quantificati. Ad esempio, i servizi del tipo NTRK non hanno mai lavorato in tali condizioni e le prestazioni di tali infrastrutture per i normali scopi topografici non sono del tutto note. Il presente lavoro introduce e quantifica i fenomeni ionosferici ciclici e descrive l’effetto sulle prestazioni del posizionamento tramite GNSS nei casi in cui vengono impiegate le tecniche NRTK e statico-relativa per reti di limitata estensione geografica.
2013
- Using Unmanned Aerial Vehicles (UAV) for High-Resolution Reconstruction of Topography: The Structure from Motion Approach on Coastal Environments
[Articolo su rivista]
Mancini, F; Dubbini, M; Gattelli, M; Stecchi, F; Fabbri, S; Gabbianelli, G
abstract
The availability of high-resolution Digital Surface Models of coastal environments is of increasing interest for scientists involved in the study of the coastal system processes. Among the range of terrestrial and aerial methods available to produce such a dataset, this study tests the utility of the Structure from Motion (SfM) approach to low-altitude aerial imageries collected by Unmanned Aerial Vehicle (UAV). The SfM image-based approach was selected whilst searching for a rapid, inexpensive, and highly automated method, able to produce 3D information from unstructured aerial images. In particular, it was used to generate a dense point cloud and successively a high-resolution Digital Surface Models (DSM) of a beach dune system in Marina di Ravenna (Italy). The quality of the elevation dataset produced by the UAV-SfM was initially evaluated by comparison with point cloud generated by a Terrestrial Laser Scanning (TLS) surveys. Such a comparison served to highlight an average difference in the vertical values of 0.05 m (RMS = 0.19 m). However, although the points cloud comparison is the best approach to investigate the absolute or relative correspondence between UAV and TLS methods, the assessment of geomorphic features is usually based on multi-temporal surfaces analysis, where an interpolation process is required. DSMs were therefore generated from UAV and TLS points clouds and vertical absolute accuracies assessed by comparison with a Global Navigation Satellite System (GNSS) survey. The vertical comparison of UAV and TLS DSMs with respect to GNSS measurements pointed out an average distance at cm-level (RMS = 0.011 m). The successive point by point direct comparison between UAV and TLS elevations show a very small average distance, 0.015 m, with RMS = 0.220 m. Larger values are encountered in areas where sudden changes in topography are present. The UAV-based approach was demonstrated to be a straightforward one and accuracy of the vertical dataset was comparable with results obtained by TLS technology.
2013
- Utilizzo di DEM in ambiente GIS per la creazione di modelli idrologici superficiali: applicazioni disponibili
[Articolo su rivista]
Caprioli, M; Mancini, Francesco; Ritrovato, G.
abstract
Il lavoro esplora le potenzialità degli strumenti disponibili in alcuni dei principali software di analisi spaziale dei dati ai fini del calcolo della rete del deflusso superficiale e dei prodotti ad esso connessi. Questi studi, generalmente condotti nell’ambito di procedure di valutazione della pericolosità dei processi idrologici e dei rischi che da essa derivano, si avvalgono oggi della maggiore disponibilità di Moelli Digitali di Elevazione (DEM), a varia risoluzione spaziale e accuratezza verticale, ottenibili da tecniche di rilevamento terrestre, aerofotogrammetrico, LiDAR. Gli algoritmi disponibili nei software GIS fanno riferimento a strategie di analisi comuni, che sono introdotte nel lavoro, ma presentano un livello di interazione con l’utente molto variabile e solo raramente consentono l’integrazione di informazioni provenienti dalle altre discipline coinvolte (geomorfologia, geologia, ingegneria geotecnica). Per alcuni di questi software, non necessariamente specializzati nei modelli idrologici, il lavoro offre inizialmente una panoramica relativa agli aspetti appena citati che, tuttavia, non riguarda l’accuratezza complessiva dei prodotti ottenuti. In seguito, grazie ad analisi condotte con il software TauDEM su tre aree-studio collocate nei territori del Sub-Appennino Dauno (Puglia), il lavoro ha verificato le prestazioni raggiunte nell’estrazione del reticolo del deflusso. Questo in relazione alla differente orografia prevalente per le tre aree e per prodotti altimetrici indipendenti caratterizzati da una risoluzione spaziale variabile: 40, 20 e 8 metri. L’analisi ha prodotto dei reticoli idrografici che risultano coerenti tra loro e con il reale assetto territoriale solo per ambienti collinari e misti. Come atteso, la definizione spaziale dei reticoli idrografici è migliore per modelli altimetrici di maggiore qualità, mentre da un confronto con un reticolo di riferimento le discrepanze sulle lunghezze delle aste fluviali (fino ad un valore massimo del 16%), sono giustificate da alcune, limitate, difformità nei risultati della gerarchizzazione delle aste idrografiche.
2012
- Attività solare, effetti ionosferici e servizi NRTK: quali connessioni?
[Articolo su rivista]
Mancini, Francesco; Dubbini, M; Stecchi, F.
abstract
L’attività solare si trova in un periodo di rapida crescita all’interno
di un ciclo periodico della durata di 11 anni. Il campo magnetico
terrestre ne è influenzato e con esso l’equilibrio dello strato superiore
dell’atmosfera terrestre, la ionosfera, dove la propagazione dei segnali
GNSS subisce i ben noti fenomeni di rifrazione. Considerato l’ulteriore
incremento di attività solare fino ai massimi previsti per 2013, ci saranno ripercussioni sulle prestazioni dei servizi NRTK?
2012
- Climate Alteration in the Metropolitan Area of Bari: Temperatures and Relationship with Characters of Urban Context
[Relazione in Atti di Convegno]
Loconte, P; Ceppi, C; Lubisco, G; Mancini, Francesco; Piscitelli, C; Selicato, F.
abstract
Urban planning exerts influences on environmental, social and economic system related with the city. Processes of land transformation and city growth determine radical changes in urban landscape morphology and as a consequence they affect air temperature and energy exchange. The urbanization can bear on local climate more intensively than the global warming does. This is due to the rapidity of human made changes related to natural ones. The present work analyzes the state of the art of studies involved in studying urban climate anomalies – Urban Heat Islands (UHI) – in order to explore relationship between urban planning morphology and urban climate. The research aim wants to indentify how urban geometry can be related with climate alterations in order to provide guidelines for planners to frame urban form planning and environmental quality. The case study is the city of Bari, located on the coast of the Mediterranean sea, in Apulia, one of the regions in Italy.
2012
- Vulnerability to ground deformation phenomena in the city of Tuzla (BiH): a GIS and multicriteria approach
[Articolo su rivista]
Stecchi, F; Mancini, Francesco; Ceppi, C; Gabbianelli, G.
abstract
Ground deformation phenomena affecting the town of Tuzla (Bosnia Herzegovina), as consequence of underground salt deposits exploitation, have been surveyed since 60 years ago. The growing of cavities beneath the town and successive surface deformations have induced several hazard factors such as ground subsidence, deep and
shallow fracturing and intense groundwater table oscillations. Fortunately, this processes had no catastrophic consequences such as sinkholes developing. Previous studies analyzed
the historical database of topographic and piezometric data and highlighted a cumulative subsidence rate up to 12 meters over a period spanning from the 1956 to the 2003. Fractures arose as obvious result of ground deformation and caused damages and demolitions to thousands of buildings, with almost 15,000 people evacuated. Nowadays, in order to diminish the deformation processes, a strong reduction in brine withdrawal has been introduced by the local authorities. This caused an uplift of the water table which actually makes the spatial pattern of deformation more complex. In fact, in the most urbanized area, the sinking phenomena are now turning into uplift displacements. The presence of such a hazard required an urban vulnerability assessment able to support local authorities in the forthcoming planning procedure. The vulnerability assessment of urban elements over a wide area, potentially affected by deformation phenomena, has been accomplished by an integration between GIS solutions and a multicriteria approach based on ELECTRE-TRI methodology. The vulnerability procedure is able to define a discrete map where the 50 9 50 m width elementary cells report the most vulnerable parts of the town. In particular, the ELECTRE-TRI methodology is used to combine each vulnerable urban element with the others, expressed as vector data in a geographical dataset. The multicriteria approach is performed outside the GIS environment by the ELECTRE-TRI 2.0 package and requires a preliminary rasterization of the used dataset.
2011
- Ground surface deformation of the urban area in complex engineering-geological conditions in the sinking town of Tuzla (Bosnia and Herzegovina)
[Relazione in Atti di Convegno]
Sijerčić, I; Dervišević, R; Čeliković, R.; Mancini, Francesco; Stecchi, F.
abstract
deformation of the ground surface and buildings in the town of Tuzla. The southern edge of the deposit dips beneath the northern part of the town. Although relatively small size, the deposit represents an extremely complex geological body The slow, natural processes of dissolution of the deposit's eastern part were accelerated by industrial exploitation of saline water (brine) that lasted over 100 years. Exploitation of the western part of the deposit started much later in 1967, by classical dry underground mining. Natural processes and applied exploitation works endangered part of the town above the deposit. Subsidence has reached its peak in 70-s of the last century, when the city lost huge number of its residential, commercial and cultural facilities. Although the salt exploitation ended (2004 and 2007) very complex processes of degradation of wider deposit environment and urban areas are still ongoing, with visible consequences on the ground surface. Featured are the geodynamic phenomena and deformation caused by a complex
structural-tectonic structure of the terrain. Analyzed were also geodetic monitoring data for the period 1956-2010 which present important information about the processes of ground surface movements. Deformation on the ground surface is being developed under the influence of various factors. In the part of the town that was investigated and presented in this paper, the consequences of the salt deposit exploitation on the ground surface are predisposed by complex terrain structure.
2011
- Il supporto della geomatica alle attività pianificatorie: analisi del rischio nella città di Tuzla (BiH)
[Articolo su rivista]
Mancini, Francesco; Ceppi, C; Stecchi, F; Gabbianelli, G.
abstract
I fenomeni di deformazione del suolo che interessano la città di Tuzla (Bosnia Erzegovina) fin dalla metà del secolo scorso sono correlate alle attività di estrazione di salgemma da depositi localizzati a poche centinaia di metri dalla superficie in corrispondenza del centro storico della città. Tale sfruttamento è avvenuto sia tramite escavazione mineraria “a secco” sia con prelievo incontrollato di salamoia per mezzo di pozzi, ed ha prodotto forti squilibri nell’assetto idrogeologico con formazione di cavità e deformazioni superficiali di entità considerevole che, fortunatamente, non hanno prodotto le tipiche
dinamiche dei sinkholes, ma un graduale collasso e fratturazione degli strati più superficiali. L’evoluzione storica di questi processi è stata quantificata grazie all’elaborazione dei dati di livellazione acquisiti fin dai primi anni ’50 per opera della Municipalità di Tuzla e mai analizzati. Tali dati hanno evidenziato spostamenti annui che hanno
raggiunto i 50 cm e valori cumulativi che raggiungono i 12 metri nel
periodo 1956-2003. Fenomeni di questa entità hanno provocato oltre
un migliaio di crolli e danneggiamenti gravi all’edificato, l’evacuazione
di circa 15000 abitanti, la modifica della viabilità principale e altri disagi per i residenti. Attualmente si riscontra nell’area una diminuzione dei tassi di deformazione superficiale a seguito della forte riduzione nelle attività estrattive, ma la situazione pregressa ha richiesto una prima fase di delimitazione delle aree soggette a deformazione e, soprattutto, una valutazione del rischio (Risk Assessment) in seguito ai fenomeni citati per l’insediamento urbano. Tale valutazione, condotta dagli autori in ambiente GIS, ha richiesto la quantificazione degli elementi di pericolosità (Hazards) che minacciano l’area oltre alla valutazione della Vulnerabilità e dell’Esposizione dell’edificato. Inoltre è stato utilizzato il metodo multicriteri ELECTRE-TRI nella combinazione di tutti quei fattori che contribuiscono a formare l’Hazard complessivo cui è soggetta l’area. Il lavoro dimostra come, attraverso la conoscenza di Hazard, Vulnerabilità ed Esposizione, sia possibile arrivare alla definizione della mappa del rischio che quantifica, su base geografica, il danno atteso in relazione ai fenomeni descritti. Tale informazione rappresenta un presupposto fondamentale nelle future attività pianificatorie che dovranno tenere in considerazione l’assetto del territorio descritto nel lavoro.
2010
- Analisi del rischio nella città di Tuzla (BiH) in relazione ai fenomeni di deformazione del suolo in seguito all’estrazione di salgemma
[Relazione in Atti di Convegno]
Stecchi, F; Mancini, Francesco; Gabbianelli, G.
abstract
Ground subsidence triggered by salt mining from deposits located beneath the city of Tuzla (Bosnia and Herzegovina) is one of the major dangers acting on a very densely urbanized area since 1950, when the salt deposit exploitation by means of boreholes began. As demonstrated in this paper, subsidence induced several hazard factors such as severe ground deformations, the arising of deep and superficial fractures and a very fast water table rise, connected with the brine extraction, now affecting several districts. The above mentioned factors have been quantified by the use of geomatics methodologies, including field surveys and analysis of geographical data. In order to estimate the historical sinking rates, authors processed the large (and never before processed) amount of topographical data collected during two periods; from 1956 to 1991, and from 1992 to 2003, with only poor data collected. Afterward, traditional surveys were completely and definitively stopped. The analysis reveals a cumulative subsidence as high as 12 m during the whole period, causing damage to buildings and infrastructures within an area that includes a large portion of the historical town, at present almost entirely destroyed. Modern sinking rates have been monitored with static GPS whereas the presence of superficial fractures monitored with kinematic GPS. Factors related to the presence of deep fractures and water table rise have been evaluated by curvature analysis techniques and piezometric data respectively. Finally, hazard factors have been combined in a risk map using the GIS (Geographical Information System) map algebra capabilities and a
simple multicriteria decision analysis (MDA). In order to do that, a vulnerability map has been derived on the basis of information reported on a couple of recently sensed high resolution satellite imageries. The final risk, arisen from the combination of single hazard factors and vulnerability map, highlights critical scenarios and unsuspected threatening that are under consideration by the local decision makers and urban planners. In particular, as highlighted in the final risk map, the present-day water table rise, triggered by the decrease in brine pumping, is seriously posing a threat to a portion of the city which
is not the most involved in ground deformations.
2010
- G.I.S. to support environmental sustainability in manufacturing areas. Case study of the Apulian Region in Southern Italy
[Relazione in Atti di Convegno]
Selicato, F; Maggio, G; Mancini, Francesco
abstract
This work addresses the potential of using Geographic Information Systems (G.I.S.) to support urban planning. In the case in point, the tool has been adopted to carry out a census of all the manufacturing plants in the Apulian Region, in the context of a working agreement between the Apulian Regional Board and the Department of Architecture and Urban Planning of Bari Polytechnic. After analysing the need to identify territorial governance systems that can support sustainable management of industrial areas, the work illustrates the data collection methods, how the dedicated Geodatabase structure was set up, what data were collected and some analyses that could then be made. In conclusion, the potential of using G.I.S for urban planning in manufacturing areas is discussed, as well as some critical elements. Among these, the need for continual data updating to fully exploit this potential is underlined.
2010
- GIS and statistical analysis for landslide susceptibility mapping in the Daunia area (Italy)
[Articolo su rivista]
Mancini, Francesco; Ceppi, Claudia; Ritrovato, Giuliano
abstract
This study focuses on landslide susceptibility mapping in the Daunia area (Apulian Apennines, Italy) and achieves this by using a multivariate statistical method and data processing in a Geographical Information System (GIS). The Logistic Regression (hereafter LR) method was chosen to produce a susceptibility map over an area of 130 000 ha where small settlements are historically threatened by landslide phenomena. By means of LR analysis, the tendency to landslide occurrences was, therefore, assessed by relating a landslide inventory (dependent variable) to a series of causal factors (independent variables) which were managed in the GIS, while the statistical analyses were performed by means of the SPSS (Statistical Package for the Social Sciences) software. The LR analysis produced a reliable susceptibility map of the investigated area and the probability level of landslide occurrence was ranked in four classes. The overall performance achieved by the LR analysis was assessed by local
comparison between the expected susceptibility and an independent
dataset extrapolated from the landslide inventory. Of the samples classified as susceptible to landslide occurrences, 85% correspond to areas where landslide phenomena have actually occurred. In addition, the consideration of the regression coefficients provided by the analysis demonstrated that a major role is played by the “land cover” and “lithology” causal factors in determining the occurrence and distribution of landslide phenomena in the Apulian Apennines
2010
- Horizontal movements of the ground surface in the zone of influence of salt exploitation in Tuzla (Bosna and Herzegovina)
[Relazione in Atti di Convegno]
Čeliković, R; Dervišević, R; Sijerčić, I; Salihović, R; Mancini, Francesco; Stecchi, F.
abstract
This paper focuses on surface movements determined by geodetic methods and occurred as consequence of brine extraction from Tuzla salt deposit (Bosnia and Herzegovina). Previous studies were mainly focalized on vertical movements, but important information about behavior of the deposit
is also available from horizontal movement data. In the case of Tuzla salt deposit the geometry and spatial location of leached/empty spaces are unknown and the comparative analysis of vertical and horizontal movement could be really significant. The spatial identification of points with high values of vertical
and horizontal movements depends on the geometry of empty spaces. Horizontal movements investigation has been carried out analyzing data collected by several geodetic measurements. The results obtained by the correlated spatial analysis of vertical and horizontal movements, can identify basic geometric characteristics of the leached/empty spaces. The discussed temporal intervals are two characteristic periods, referred to the capacity of the deposit exploitation. Movement rates per year and correlation between horizontal and vertical movements are considered as indicator parameters defining the character of ground deformation. Spatial analysis of these coefficients values has identified high risk areas, and gives additional information in the geological structures definition.
2009
- Dati satellitari e GPS nelle applicazioni archeologiche: ricostruzione della paleo-geografia nell’area del sito di Lothal (Gujarat, India)
[Relazione in Atti di Convegno]
Mancini, Francesco; Stecchi, F; Marcheselli, G.
abstract
Il lavoro illustra alcuni dei risultati raggiunti nell’ambito delle attività di ricerca condotte in prossimità del sito archeologico di Lothal (Saurashtra peninsula Stato del Gujarat, India nord-occidentale). Il sito rappresenta uno dei principali insediamenti della civiltà della Valle dell’Indo ed in particolare di quella Harappana (circa 2400 anni a.C). Ai fini delle considerazioni archeologiche relative alla localizzazione dello sito, occorre procedere alla ricostruzione degli aspetti paleo-geografici dell’area ed al rilievo morfologico di dettaglio del sito stesso. Esso rappresenta probabilmente un antico porto inserito in un contesto idrografico oggi non più presente, essendo l’area molto distante dal mare è non più coinvolta dalla circolazione delle acque superficiali. Pertanto la formulazione di teorie archeologiche relative allo sviluppo ed al declino dell’insediamento passano attraverso la ricostruzione degli aspetti paleo-geografici dell’area, nel contesto dei cicli climatici recenti, e della morfologia del sito, in quanto quest’ultimo doveva necessariamente risultare protetto all’interno della pianura tidale in cui si trovava.
2009
- GIS-based assessment of risk due to salt mining activities in the city of Tuzla (Bosnia and Herzegovina)
[Articolo su rivista]
Mancini, Francesco; Stecchi, Francesco; Gabbianelli, Giovanni
abstract
Ground subsidence triggered by salt mining from deposits located beneath the city of Tuzla (Bosnia and Herzegovina) is one of the major dangers acting on a very densely urbanized area since 1950, when the salt deposit exploitation by means of boreholes began. As demonstrated in this paper, subsidence induced several hazard factors such as severe ground deformations, the arising of deep and superficial fractures and a very fast water table rise, connected with the brine extraction, now affecting several districts. The above mentioned factors have been quantified by the use of geomatic methodologies, including field surveys and analysis of geographical data. In order to estimate the historical sinking rates, authors processed the large (and never before processed) amount of topographical data collected during two periods; from 1956 to 1991, and from 1992 to 2003, with only poor data collected. Afterward, traditional surveys were completely and definitively stopped. The analysis reveals a cumulative subsidence as high as 12 m during the whole period, causing damage to buildings and infrastructures within an area that includes a large portion of the historical town, at present almost entirely destroyed. Modern sinking rates have been monitored with static GPS whereas the presence of superficial fractures monitored with kinematic GPS. Factors related to the presence of deep fractures and water table rise have been evaluated by curvature analysis techniques and piezometric data respectively. Finally, hazard factors have been combined in a risk map using the GIS (Geographical Information System) map algebra capabilities and a simple multicriteria decision analysis (MDA). In order to do that, a vulnerability map has been derived on the basis of information reported on a couple of recently sensed high resolution satellite imageries. The final risk, arisen from the combination of single hazard factors and vulnerability map, highlights critical scenarios and unsuspected threatening that are under consideration by the local decision makers and urban planners. In particular, as highlighted in the final risk map, the present-day water table rise, triggered by the decrease in brine pumping, is seriously posing a threat to a portion of the city which is not the most involved in ground deformations.
2009
- Monitoring ground subsidence induced by salt mining in the city of Tuzla (Bosnia & Herzegovina)
[Articolo su rivista]
Mancini, Francesco; Stecchi, Francesco; Zanni, Michela; Gabbianelli, Giovanni
abstract
Salt mining induced ground subsidence is a major hazard in the city of Tuzla (Northeastern sector of Bosnia and Herzegovina) and its surroundings since 1950, when solution mining of salt deposits by boreholes began. An analysis of the large (and never before processed) amount of topographical data collected during two periods: from 1956 to the Balkan War, and from 1992 to 2003 has been made. The analysis reveals a cumulative subsidence as high as 12 m during the whole period, causing damage to buildings and infrastructures within an area that includes a large portion of the historical town. Human-induced subsidence, (with rates up to 40 cm/year in the most developed area), has been investigated to recognize the areas affected by the sinking phenomenon and to produce a subsidence hazard. The time series of topographical observations have been enlarged by conducting new surveys in the urban area by modern space-geodesy methodologies, such as static
relative GPS (Global Positioning System) and high resolution satellite imageries. The GPS monitoring started in 2004 and detected a decrease in the subsidence rates to 20 cm/year related to the reduction of salt exploitation. There is close correlation between the average subsidence rate and the annual amount of salt extracted
2009
- Uso di Modelli Digitali del Terreno nella valutazione della propensione al dissesto dei versanti su base statistica
[Relazione in Atti di Convegno]
Mancini, Francesco; Ritrovato, G; Ceppi, C.
abstract
The potential of predictive methods for landslide occurrences in a GIS environment and on statistical basis has been dealt with by the paper for a wide area across the Southern Italian Apennines (sector of Daunia, Puglia). These methods require a comprehensive knowledge of geographical variables, mostly but not entirely related to morphology, and are able to tie such variables with the occurrence/not occurrence of landslides phenomena within the area of interest. In particular, this study introduces the determination of relevant variables (causal factors) in the study of slope instability and failure that must necessarily be derived from reliable Digital Elevation Model (DEM) and analyzes the characteristics of accuracy and resolution that such models should exhibit in accordance to the scale of investigation and data collecting and/or mapping. The implementation of these and other factors in a
Logistic Regression Model (LRM) allowed to calculate the proneness to failure (landslide susceptibility) on a statistical basis through the establishment of the existing relationship between causal factors and presence or absence of landslide phenomena. Therefore, for each of the model resolution cells the likely of investigated phenomena are being quantitatively assessed and, hence, a landslide susceptibility map created. Result are finally validated by comparing the theoretical proneness to landslides with data included in the available inventory
2008
- Analisi del rischio da frana in ambiente GIS: Il caso del Sub-Appennino Dauno (Puglia)
[Relazione in Atti di Convegno]
Mancini, Francesco; Ceppi, C; Ritrovato, G.
abstract
Il presente studio è il frutto del lavoro svolto all’interno di un progetto di ricerca finanziato dalla Regione Puglia e dall’unione Europea, che ha come principale scopo quello di valutare il rischio da frana nei centri minori del Sub-appennino Dauno. Allo scopo di produrre, a scala regionale, una carta della suscettività da frana, intesa come propensione al dissesto, nel lavoro vengono discusse le tecniche utilizzate per il trattamento dei dati e le modalità di inserimento delle variabili in ambiente GIS. Tali variabili hanno costituito un affidabile campione di partenza per l’analisi statistica della suscettività basata su un modello di regressione logistica. Si mostrano i risultati ottenuti attraverso l’analisi applicata a due campioni di dati, il primo comprendente la totalità delle informazioni ed il secondo suddiviso in due porzioni, la prima utilizzata per l’analisi e la seconda nella verifica dell’accuratezza nella determinazione della suscettività da frana. Tale valore, in entrambi i casi, si attesta sul 75% circa dimostrando anche che il risultato è indipendente dalla numerosità del campione iniziale.
2008
- Analysis of Multispectral Satellite Images for Evaluating Ice Stream Velocities
[Articolo su rivista]
Bitelli, G; Gusella, L; Mancini, Francesco; Pino, I; Vittuari, L.
abstract
Multitemporal satellite images can be used to determine the velocity field, an important parameter in the study of ice streams, by measuring the displacement of features on the moving glacier surface. Bindschalder and Scambos (1991) developed and tested a numerical cross-correlation method for measuring the velocity of crevasses and related features on multitemporal satellite imagery. This paper describes the application of the cross-correlation method to the Scott Coast (Victoria Land, East Antarctica) and in particular to the Drygalski Ice Tongue and David Glacier; Landsat images from 1973 to 2001 were used in this study.
2008
- Indagini di carattere ambientale attraverso l’analisi di dati multispettrali Landsat ed ASTER
[Articolo su rivista]
Mancini, Francesco; De Giglio, M; Nurra, M.
abstract
The paper focuses on the use of multispectral satellite data for environmental monitoring along a portion of the Emilia-romagna coastal area where natural (wetland and salt intrusions) and anthropical (agricultural exploitations) aspects interact and modify the original ecological equilibrium. The environmental properties of wet and dry areas have been investigated by classification of satellite data acquired from Landsat TM 4/5, ETM+ and Terra-ASTER platforms acquired since 1986 to 2002. Results, specific properties of transitional environments that were highlighted by the analysis and possible validation procedures are addressed.
2008
- Inquadramento delle reti regionali VLNDEF e TAMDEF (Antartide) nel sistema di riferimento globale
[Relazione in Atti di Convegno]
Capra, Alessandro; Galeandro, A; Mancini, Francesco; Negusini, M; Vittuari, L.
abstract
L’obiettivo del presente lavoro è di definire le strategie più opportune per l’inquadramento delle reti antartiche di stazioni permanenti ed episodiche in un sistema di riferimento globale. Lo studio è stato focalizzato in particolare sulla rete antartica di stazioni permanenti e sulle sottoreti regionali VLNDEF e TAMDEF, allo scopo di ottenere informazioni circa la cinematica superficiale della Terra Vittoria (Antartide). L’approccio scelto per l’inquadramento è stato sviluppato in tre fasi: inquadramento delle stazioni permanenti presenti nella regione oggetto di studio, connessione dei siti delle due reti regionali alle stazioni permanenti precedentemente inquadrate, elaborazione di tutte le informazioni a livello di equazioni normali. Per l’analisi dei dati è stato utilizzato il Bernese GPS software v5.0. Per l’elaborazione dei dati sono stati utilizzati parametri e modelli standard, eseguendo per alcuni di essi dei test per verificare quanto essi incidessero sull’analisi del dato e quali fossero le scelte migliori per la soluzione finale. L’analisi delle serie storiche ha evidenziato quali stazioni permanenti fossero affidabili per la connessione delle reti regionali. L’analisi spettrale delle stesse ha messo in rilievo la presenza di segnali periodici che influenzano la determinazione delle velocità, in particolar modo per la componente verticale. I risultati ottenuti mostrano un andamento ben determinato per quanto riguarda le velocità planimetriche, mentre, sono ancora incerte, in termini di spostamento verticale assoluto, a seconda del sistema di riferimento utilizzato, ITRF2000 o ITRF2005. Questo lascia ancora irrisolto il problema dell’interpretazione dei risultati da utilizzare come condizioni al contorno per i modelli geodinamici delle zone oggetto di studio.
2008
- Misure geodetiche di inquadramento e caratterizzazione geomorfologica della baia di Algeri (Algeria)
[Relazione in Atti di Convegno]
Stecchi, F; Mancini, Francesco; Gabbianelli, G.
abstract
Nell’ambito del Progetto Internazionale “Algerian coast Management through Integration and Sustainability (AMIS) – SmapIII Project (CE contract MED/2005/110-661) per il quale il CIRSA (Centro Interdipartimentale di Ricerca per le Scienze Ambientali) dell’Università di Bologna ha svolto un ruolo di coordinamento tra vari partner italiani e l’APPL (Agenzia di Protezione e Promozione del Litorale) algerino, sono state effettuate delle prime indagini ai fini dell’inquadramento geodetico e della caratterizzazione geomorfologia di una vasta area costiera (Wilaya D’Alger) che comprende la totalità della baia di Algeri ed i tratti costieri limitrofi. Con queste finalità sono state acquistate, a totale copertura dell’area, diverse immagini satellitari QuickBird, ad alta risoluzione, insieme ad una coppia di ricevitori GPS di classe geodetica. Le prime costituiscono un elemento cartografico aggiornato su cui basare la progettazione dell’intero lavoro mentre i secondi sono stati utilizzati in tutte le fase del rilievo sia di inquadramento sia di dettaglio. Le attività descritte in questo lavoro sono parte di un più ampio progetto di indagine che include anche i rilievi batimetrici dei fondali prospicienti l’area descritta. Il tutto finalizzato alla modellizzazione dei processi idrodinamici costieri. Inoltre, nella sua globalità, il progetto AMIS prevede anche un’attività formativa nelle diverse, ed ampie, discipline che svolgono un ruolo nell’ambito di tutte le iniziative di management costiero. In questo scritto si parlerà, in particolare, della formazione svolte nelle materie del Remote Sensing e del rilevamento geodetico e topografico GPS.
2008
- Strumenti innovativi per la gestione sostenibile delle aree industriali: gli insediamenti produttivi della Regione Puglia
[Relazione in Atti di Convegno]
Selicato, F; Mancini, Francesco; Maggio, G.
abstract
Il lavoro analizza le potenzialità offerte dall’utilizzo dei Sistemi Informativi Territoriali nell’ambito della pianificazione urbanistica. In particolare tale strumento è stato predisposto ai fini del censimento degli insediamenti produttivi dell’intera Regione Puglia condotto nell’ambito di un’attività di convenzione tra Regione Puglia (attraverso la concessionaria FinPuglia) e Dipartimento di Architettura e Urbanistica (Politecnico di Bari). Dopo
un’introduzione sull’esigenza di individuare strumenti di governo del territorio che supportino una gestione sostenibile delle aree industriali, il lavoro illustra le modalità di raccolta delle informazioni, la realizzazione della struttura del Geodatabase concepito a tal fine,i dati raccolti ed alcune analisi possibili grazie al prodotto messo a punto. In conclusione le potenzialità del SIT per le aree produttive, nell’ambito delle discipline urbanistiche, vengono
discusse unitamente ad alcune criticità. Tra queste viene evidenziata l’esigenza del continuo aggiornamento dei dati che garantisce la piena potenzialità del prodotto.
2008
- VLNDEF Project for Geodetic Infrastructure Definition of Northern Victoria Land, Antarctica
[Capitolo/Saggio]
Capra, Alessandro; Dubbini, M; Galeandro, A; Gusella, L; Zanutta, A; Casula, G; Negusini, M; Vittuari, L; Sarti, P; Mancini, Francesco; Gandolfi, S; Montaguti, S; Bitelli, G.
abstract
Scientific investigations in Antarctica are, for many different reasons, a challenging and fascinating task. Measurements, observations and field operations
must be carefully planned well in advance and the capacity of successfully meeting the goals of a scientific project is often related to the capacity of forecasting and anticipating the many different potential mishaps. In order to do that, experience and logistic support are crucial. On the scientific side, the team must be aware of its tasks and be prepared to carry out observations in a hostile environment: both technology and human resources have to be suitably selected, prepared, tested and trained. On the logistic side, nations, institutions and any other organisation involved in the expeditions must ensure the proper amount of competence and practical support. The history of modern Italian Antarctic expeditions dates back to the middle 80’s
when the first infrastructures of “Mario Zucchelli Station”, formerly Terra Nova Bay Station, were settled at Terra Nova Bay, Northern Victoria Land. Only a few years later, the first geodetic infrastructures were planned and built. Italian geodetic facilities and activities were, ever since, being constantly maintained and developed. Nowadays, the most remarkable geodetic infrastructures are the permanent Global Positioning System (GPS) station (TNB1) installed at Mario Zucchelli and the GPS geodetic network Victoria Land Network for DEFormation control (VLNDEF) entirely deployed on an area extending between 71◦S and 76◦S and 160◦E and 170◦E. These facilities do not only allow carrying out utmost geodetic investigations but also posses interesting capacities on the international multidisciplinary scientific scenario. In order to fully exploit their potentiality, management and maintenance of the infrastructure are crucial; nevertheless, in order to perform high quality scientific research, these abilities must be coupled with the knowledge concerning a proper use and a correct processing of the information that these infrastructures can provide.
This work focuses on the different methods that can be applied to process the observations that are performed with GPS technique in Northern Victoria Land, aiming at reaching the highest accuracy of results and assuring the larger significance and versatility of the processing outcomes. Three software were used for the analysis, namely: Bernese v.5.0, Gipsy/Oasis II and Gamit/Globk. The working data sets are (i) the permanent GPS station TNB1 observations continuously performed since 1998 and (ii) the five episodic campaigns performed on the sites of VLNDEF. The two infrastructures can be regarded as neat examples of standard geodetic installation in Antarctica. Therefore, the technological solutions that were adopted and applied for establishing the GPS permanent station and the VLNDEF geodetic network as well as the data processing strategies and the data analysis procedures
that were tested on their observation will be illustrated in detail. The results will be presented, compared and discussed. Furthermore, their potentials and role in geodetic research will be carefully described; their versatility will also be highlighted in the foreground of a multidisciplinary Antarctic international scientific activity.
2008
- Vertical motions in Northern Victoria Land inferred from GPS: A comparison with a glacial isostatic adjustment model
[Relazione in Atti di Convegno]
Mancini, Francesco; Negusini, M; Zanutta, A; Capra, Alessandro
abstract
Recent development of italian geodetic reseacrh related to the comparison of defromation obtained with GPS measurements with data obtained from GIA models
2007
- Approccio multidisciplinare per lo studio del fenomeno della subsidenza nell’area di Tuzla (BiH)
[Relazione in Atti di Convegno]
Stecchi, F; Antonellini, M; Gabbianelli, G; Mancini, Francesco
abstract
Il lavoro descrive le indagini di carattere multidisciplinare effettuate nella città Tuzla (Bosnia & Herzegovina) per il monitoraggio del fenomeno della subsidenza, a seguito dell’intenso sfruttamento dei depositi di sale sottostanti, e la descrizione di effetti ad esso correlati. L’analisi della serie storica dei dati di livellazione a permesso sia la quantificazione dei movimenti in atto, che nell’arco dell’ultimo cinquantennio superano i 20 cm/anno, sia di progettare nuove indagini di carattere geologico, geofisico e geodetico ai fini di una maggiore comprensione del fenomeno. Tali informazioni, organizzate in ambiente di lavoro G.I.S. sono finalizzate alla valutazione del rischio indotto dall’estrazione di sale in ambiente urbanizzato
2007
- GPS as a geodetic tool for geodynamics in northern Victoria Land, Antarctica
[Articolo su rivista]
Capra, A.; Mancini, F.; Negusini, M.
abstract
The VLNDEF (Victoria Land Network for DEFormation control) project started in 1999 with the aim of detecting crustal deformation in Northern Victoria Land (Antarctica) over an area that had never been surveyed by a dense GPS network before. After a brief summary of the Italian geodetic activities carried out since 1991, the paper presents the results obtained from the processing of data collected from 1999 to 2003. In particular, processing strategies were dealt with, in order to produce horizontal and vertical displacement maps through GPS observations. Absolute motions in a global reference frame have been investigated using a double approach, which allowed us to make considerable progress in detecting movements and standardizing the data analysis. The analyses provide absolute horizontal velocities ranging between 17 mm yr(-1) and 8 mm yr(-1), with greater motions in the northernmost area. The subtraction of the rigid plate motion provides relative displacements, which may contribute to the understanding of neotectonics and geology, whereas the pattern of the vertical crustal motions detected, with average values of +1.3 mm yr(-1), is essential to detect the effect of Glacial Isostatic Adjustment (GIA) and other geophysical signals, and to redefine theory and numerical models used without any direct measurements.
2007
- Thermal properties of ice bodies in East Antarctica: exploiting ASTER data in the Northern Victoria Land area
[Relazione in Atti di Convegno]
Mancini, Francesco; De Giglio, M.
abstract
The paper addresses the use of TERRA-ASTER thermal infrared data for investigation of ice and bedrocks properties in the Northern Victoria Land, East Antarctica. Data acquired by the TIR (Thermal Infrared Radiometer) sub-system were processed in order to retrieve information about the ground temperature and thermal anomalies over a coastal area characterized by the presence of glaciers, ice shelves, exposed bedrock, sea-ice and the Mount Melbourne volcanic edifice. As discussed in this paper, a deeper knowledge of the ice mass exchanges dynamics could be therefore derived from the analysis of the thermal properties at the ground which have the potential to highlight features that are undetectable by the use of visible channels
2006
- Caratterizzazione di ambienti vallivi mediante informazioni storiche e dati telerilevati
[Relazione in Atti di Convegno]
Mancini, Francesco; Nurra, M.
abstract
Il lavoro riguarda lo studio del sistema delle Valli di Comacchio attraverso l’analisi di documentazione storica e l’utilizzo di dati satellitari Landsat per la caratterizzazione di alcuni aspetti idrodinamici relativi al processo di mescolamento tra acque costiere ed interne. I risultati ottenuti consentono una quantificazione dei lineamenti evolutivi del sistema vallivo ed evidenziano un regime idrodinamico costiero e vallivo ampiamente confermato da indagini puntuali e precedenti studi.
2006
- G.I.S. as a tool for data management and ground deformations analysis in the city of Tuzla (BiH)
[Relazione in Atti di Convegno]
Stecchi, F; Mancini, Francesco; Gabbianelli, G.
abstract
G.I.S. as a tool for data management and ground deformations analysis in the city of Tuzla (BiH)
2006
- Historical Shoreline Changes at an Active Island Volcano: Stromboli, Italy
[Articolo su rivista]
Romagnoli, C; Mancini, Francesco; Brunelli, R.
abstract
Rapid shoreline changes at Stromboli Island have been documented from maps and aerial photographs dating from 1938 to 2003. Shorelines digitized from aerial photographs, taken at decadal intervals on average, show that while cliffed tracts were relatively stable, beaches on the N and NE side of the island experienced alternating accretion and erosional stages linked, respectively, with the contemporary eruptions and with sediment redistribution and/or the washing out and loss of sediment to deeper waters. Sciara del Fuoco, on the central-western side of the island, is where most of the volcanic products have accumulated during the practically continuous activity of the last two thousands years; from there, sands and gravel drift alongshore and are added to beaches on the N and NE side of the island. A simple model of clockwise longshore drift along the W, N, and NE coasts of the island is presented, taking into account the influences of manmade structures on shoreline changes.
2006
- Monitoraggio del territorio rurale nell’area emiliano-romagnola mediante dati ASTER
[Relazione in Atti di Convegno]
Barbarella, M; De Giglio, M; Mancini, Francesco
abstract
Il lavoro presenta alcuni risultati relativi all'analisi dell'uso del suolo nell'area emiliano-romagnola, con particolare riferimento all'utilizzo agricolo, attraverso metodi di classificazione supervisionata e non a partire da dati satellitari multispettrali del sensore ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer). Particolare attenzione è dedicata ad alcune problematiche relative alla disponibilità di dati a terra affidabili ed
aggiornati, alla loro raccolta ed alla necessità di un’ integrazione finalizzata alle fasi di istruzione degli algoritmi di classificazione e di verifica dei risultati ottenuti. L'obiettivo è la messa a punto di metodologie affidabili ed il più possibile automatizzate per il monitoraggio del territorio.
2006
- Processamento di scene satellitari ASTER per la caratterizzazione dell’area Antartica di Baia Terra Nova
[Altro]
Bellanova, A.; Angelini, M. G.; Capra, A.; Immordino, F.; Mancini, F.
abstract
2005
- Analisi multitemporale di immagini satellitari per la determinazione del campo superficiale di velocità di ice-streams in Antartide
[Articolo su rivista]
Bitelli, G; Frezzotti, M; Gusella, L; Mancini, Francesco; Pino, I.
abstract
Il lavoro descrive l’utilizzo di immagini satellitari Landsat, disponibili su un periodo di oltre 30 anni (1972-2001), ai fini della determinazione del campo superficiale di velocità di alcuni ice-streams
in Antartide (settore Pacifico). Vengono illustrate le tecniche di pretrattamento dei dati satellitari precedenti l’analisi per correlazione, del tipo area based, che, applicata a coppie di immagini, consente di determinare le velocità superficiali di ice-streams e di altri corpi in movimento. Lo scopo del lavoro è quello di automatizzare, per quanto possibile, l’intera procedura e giungere alla messa a punto di una metodologia di monitoraggio in grado di fornire parametri relativi alla dinamica di aree glaciali del continente antartico, parametri utili nel contesto della ricerca sull’evoluzione delle calotte polari e quindi nel più ampio campo dello studio dei mutamenti globali.
2005
- Deformazioni orizzontali verticali della Terra Vittoria Settentrionale, Antartide
[Relazione in Atti di Convegno]
Capra, A.; Dubbini, M.; Mancini, F.; Montaguti, S.; Negusini, M.; Vittuari, L.; Zanutta, A.
abstract
2005
- Ground collapsing in the city of Tuzla (Bosnia & Herzegovina)
[Relazione in Atti di Convegno]
Mancini, Francesco; Stecchi, F; Gabbianelli, G; Dzindo, A.
abstract
Since the year 1955, when the salt deposits exploitation activities were carried out in the city of Tuzla and surroundings, dramatic ground collapsing phenomena occurred. Up to 10 meters of sinking in the last half century produced several damages with regards to buildings and infrastructures, leading to the demolition of the most compromised part of the city by the inhabitants. Traditional topographic survey was used in order to monitor the land deformations from the 50' to year 2000 with the establishment of a dense topographic network around the sinking area. The analisys of the huge dataset
of altimetric data, the correlation with the boreholes activities and the introduction of more productive modern technologies (satellite GPS for geodesy) for repeated land monitoring are the object of this paper.
2005
- I dati ASTER: indagini di carattere ambientale nell’area emiliano - romagnola
[Relazione in Atti di Convegno]
Barbarella, M; De Giglio, M; Mancini, Francesco
abstract
L’utilizzo dei dati multispettrali forniti dal sensore satellitare ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) ha consentito un ulteriore sviluppo negli studi di carattere ambientale finalizzati al monitoraggio del territorio. La sperimentazione effettuata, relativa all’area costiera emiliano-romagnola, ha avuto come obiettivi principali il riconoscimento dell’uso del suolo, delle coperture vegetali e la caratterizzazione delle acque interne e costiere, tramite i principali algoritmi di classificazione. La preventiva conoscenza delle reali destinazioni d’uso è stata attuata mediante la consultazione di una serie di fonti rese disponibili dagli Enti pubblici e privati contattati. Sulla base di tali dati è stata anche verificata l'attendibilità del processo di analisi.
2005
- Il controllo delle deformazioni del suolo nella città di Tuzla (Bosnia & Erzegovina)
[Relazione in Atti di Convegno]
Mancini, Francesco; Stecchi, F; Gabbianelli, G.
abstract
L’intenso sfruttamento dei depositi di sale sottostanti la città di Tuzla (Bosnia & Herzegovina) a partire dalla metà degli anni ’50, ha indotto vistosi fenomeni di subsidenza ed episodi di collassamento del terreno. Le deformazioni del terreno conseguenti l’attività di estrazione vengono monitorate già dal 1956 grazie ai numerosissimi rilievi topografici con tecniche tradizionali effettuati su di una fitta rete topografica realizzata nell’area. Gli abbassamenti misurati nel periodo citato sono quantificabili, nelle aree maggiormente coinvolte, in una decina di metri con effetti catastrofici su buona parte dell’area storica della città e con gravi danni agli edifici, infrastrutture ed alle reti tecnologiche. A partire dal 2002, nell’ambito di una collaborazione tra municipalità di Tuzla e Provincia di Ravenna, è stato effettuato un riordino dell’enorme archivio di dati altimetrici unitamente all’introduzione di moderne tecniche di rilievo (GPS e Telerilevamento) a supporto del monitoraggio di fenomeni ancora intensi nell’area, correlati con l’attività estrattiva.
2005
- Recent variations of a debris-covered glacier (Brenva glacier) in the Italian Alps monitored by comparison of maps and digital orthophotos
[Articolo su rivista]
D'Agata, C; Smiraglia, C; Zanutta, A; Mancini, Francesco
abstract
Debris-covered glaciers are widespread in the mountain chains of Asia. They are also particularly common in New Zealand , in the Andes and in Alaska. Despite their relatively common occurrence, debris-covered glaciers have not been well studied. A debris cover that partially or completely masks the glacier ablation zone significantly influences the surface energy flux, the ablation rate and the discharge of meltwater streams. A multi-temporal analysis based on photogrammetry methodologies was used to assess changes volume and ablation rates.
2005
- Terra Nova Bay GPS permanent station (Antarctica): data quality and first attempt in the evaluation of regional displacement
[Articolo su rivista]
Negusini, M; Mancini, Francesco; Gandolfi, S; Capra, Alessandro
abstract
The paper discusses the long time series analysis of GPS permanent station located at Terra Nova Bay, East Antarctica (Victoria Land). The station (TNB1) was monumented during the 1997–1998 Italian expedition in Antarctica and the data collection started on January 1998. TNB1 is included in the Victoria Land network for deformation control (VLNDEF) network that was established with the aim to study the horizontal and vertical displacements in the region.
The good-quality data obtained from this station allow the computation of long time series performed both by using a network approach with Bernese V4.2, and precise point positioning technique with GIPSY–OASIS II. In a first step, a subset of data was analysed to define the best processing strategy. Moreover, in the network approach, international GPS service (IGS) permanent stations (intra- and extra-plate) were used.
Results obtained from the two approaches are comparable in terms of both repeatability and linear trend. Finally, velocities estimated for all Antarctic stations were compared to the values provided by ITRF2000. In most cases horizontal velocities agree with the model, while significant differences are present along the vertical components.
2004
- Geophysical survey at Talos Dome (East Antarctica): the search for a deep new drilling site
[Articolo su rivista]
Frezzotti, M; Bitelli, G; Coren, F; De Michelis, P; Deponti, A; Forieri, A; Gandolfi, G; Maggi, V; Mancini, Francesco; Remy, F; Sterzai, P; Urbini, S; Vittuari, L; Zirizzotti, A.
abstract
Talos Dome is an ice dome on the edge of the East Antarctic plateau; because accumulation is higher here than in other domes of East Antarctica, the ice preserves a good geochemical and palaeoclimatic record. A new map of the Talos Dome area locates the dome summit using the global positioning system (GPS) (72°47′14″ S, 159°04′2″ E; 2318.5 m elevation (WGS84)). A surface strain network of nine stakes was measured using GPS. Data indicate that the stake closest to the summit moves south-southeast at a few cm a−1. The other stakes, located 8 km away, move up to 0.33 m a−1. Airborne radar measurements indicate that the bedrock at the Talos Dome summit is about 400 m in elevation, and that it is covered by about 1900 m of ice. Snow radar and GPS surveys show that internal layering is continuous and horizontal in the summit area (15 km radius). The depth distribution analysis of snow radar layers reveals that accumulation decreases downwind of the dome (north-northeast) and increases upwind (south-southwest). The palaeomorphology of the dome has changed during the past 500 years, probably due to variation in spatial distribution of snow accumulation, driven by wind sublimation. In order to calculate a preliminary age vs depth profile for Talos Dome, a simple one-dimensional steady-state model was formulated. This model predicts that the ice 100 m above the bedrock may cover one glacial–interglacial period.
2004
- Indagine sulle linee guida esistenti per l'esecuzione di rilievi LIDAR aerei
[Articolo su rivista]
Barbarella, M; Lenzi, V; Mancini, Francesco
abstract
La diffusione della tecnica di rilievo LIDAR da piattaforma aerea, disponibile per molteplici e diff e renti applicazioni, è stata fino ad oggi caratterizzata da un approccio sperimentale finalizzato alla produzione di modelli numerici di elevazione destinati alle singole applicazioni dove le varie fasi costituenti dell'intero rilievo venivano gestite in base all'esperienza degli utenti ed alla strumentazione disponibile. In prospettiva di una ulteriore diffusione della tecnica LIDAR aerea e di un ampliamento delle applicazioni sul territorio nazionale, si avverte l’esigenza di discutere alcuni criteri e/o specifiche relativi al rilievo che possano consentire la valutazione della qualità del rilievo stesso e del dato rilevato. In merito a questo vengono analizzate alcune esperienze condotte in ambito internazionale nella definizione di linee guida e norme da rispettare nelle varie fasi di produzione del dato. Questo al fine di garantire e certificare l'accuratezza finale del dato rilevato e la sua idoneità verso applicazioni specifiche o "multi-purposes" e quindi per associare al rilievo un valore aggiunto costituito dalla utilizzabilità dei dati per fini diversi da quelli originali. Esperienze significative in tale direzione sono state condotte da organizzazioni ed Agenzie di diversi paesi principalmente coinvolte nelle discipline del rischio idrogeologico e della modellizzazione del regime idraulico superficiale. Tra i principali contributi si segnalano quelli della Federal Emergency Agency, FEMA (Guidelines and Specifications for Flood Hazard Mapping Partner), National Digital Elevation Program, NDEP (Guidelines for Digital Elevation Data), Ecole Polytechnique Federale de Lausanne, EPFL Technical Specification for the Elaboration of Digital Elevation Model).
In Italia cominciano ad essere numerosi i casi di impiego del LIDAR per diverse applicazioni di tipo ambientale quali rilievi su aree colpite da dissesti idrogeologici (Sarno, Episcopio, Bracigliano,ecc.), rilievi di aste fluviali (Brenta, Adige, fiumi dell’Alto Adriatico, ecc.), rilievi di centri urbani (Pavia, Genova, Piombino, ecc.). In Italia esistono casi di specifiche realizzate per lavori particolari che indicano quali requisiti devono avere i dati (accuratezza, densità dei punti, ecc.) ma non esistono attualmente norme codificate e generalmente accettate a livello nazionale a cui attenersi nelle operazioni di rilievo (pianificazione del volo, qualità del segnale GPS, procedure di validazione dei dati). Lo scopo del lavoro è dunque quello di studiare gli accorgimenti proposti dai diversi autori in ambito internazionale, per analizzarne l’applicabilità alla specifica e peculiare situazione italiana relativamente alle varie fasi del processo, dalla progettazione
all’esecuzione, all’applicazioni delle metodologie di elaborazione dei dati fino ad arrivare alla verifica dell’accuratezza finale.
2004
- Integrazione di misure GPS-GLONASS, analisi di una rete di appoggio per sperimentazioni VRS
[Relazione in Atti di Convegno]
Barbarella, M; Gandolfi, S; Mancini, Francesco; Ronci, E; Vittuari, L.
abstract
na
2004
- Orthorectification of HR satellite images with space-derived DSM
[Relazione in Atti di Convegno]
Cavallini, R; Mancini, Francesco; Zanni, M.
abstract
The paper addresses the item of orthorectification of high resolution satellite images and the assessment of the final accuracy achieved when Digital Surface Models (DSM) provided by other remotely sensed data are used. By using a photogrammetric processing, a DSM was obtained from an EROS (Earth Resources Observation System) high resolution stereo pair acquired over a portion of the city of Bologna (Italy). After the accuracy assessment of the terrain model trough the comparison with external Digital Elevation Model (DEM), a broad range of orthorectification procedures with high resolution satellite images (Ikonos, QuickBird and EROS) have been therefore investigated by the authors. The accuracy in final positioning provided by the orthorectification of a QuickBird imagery with the EROS-derived elevation dataset was evaluated using a evenly spaced set of Ground Control Points from GPS survey. The achieved accuracy could meet the requirements needed in technical cartography specifications (to scale as large as 1:10000) updating of well recognizable features or entities and generic mapping procedures.
2004
- Space Geodesy as a tool for measuring ice surface velocity in the Dome C region and along the ITASE traverse.
[Articolo su rivista]
L., Vittuari; C., Vincent; M., Frezzotti; S., Gandolfi; G., Bitelli; CAPRA, Alessandro; MANCINI, Francesco
abstract
Dome C was chosen by the European Project for Ice Coring in Antarctica (EPICA) as the site for the drilling of a deep ice core. This paper presents results from geodetic surveys of ice velocities (absolute and relative) at Dome C and along a transect to Terra Nova Bay. The purpose of the surveys was to provide accurate data for the study of ice dynamics, particularly a strain network comprising 37 poles surveyed in 1995 and again in 1999. Data indicate that the ice surface at the poles closest to the topographic summit moves horizontally by up to a few mm a−1 in a direction consistent with downslope motion of the ice sheet, while 25 km from the summit it moves up to 211 mm a−1. The EPICA drilling site yields an interpolated velocity of about 15 ± 10 mm a−1 in a north-northwesterly direction. Analysis of the velocity field and surface topography reveals that the surface flow centre is nearly co-located with the dome summit, and that both are in a steady-state condition. The measured horizontal velocities are consistent with the remote-sensing result and provide accurate ground-truth control for flow mapping. Seven snow–firn cores, up to 53 m deep, were drilled during the Terra Nova Bay–Dome C traverse. Submerged velocity systems were installed at the borehole and measured using the global positioning system (GPS). First results show a steady-state condition. Measured (horizontal) ice velocities increase from the summit of the ice sheet to the coast, reaching about 28 m a−1 at site GPS2A.
2004
- VLNDEF (Victoria Land Network for DEFormation control). Monumentation during the GANOVEX VIII – ITALIANTARTIDE XV: Survey and Data Processing
[Articolo su rivista]
Mancini, F; Capra, A; Gandolfi, S; Sarti, P; Vittuari, Luca
abstract
In the frame of the 1999-2000 Italian expedition in Antarctica a scientific programme for geodynamic purposes in the northern Victoria Land begun. The new project VLNDEF (Victoria Land
Network for DEFormation control) deals with the monitoring of crustal deformations within the investigated area. The newly-monumented GPS stations and the following field geodetic surveys (hereafter discussed) extended an existing GPS geodetic network located close to the area of Terra Nova Bay where a GPS Permanent Station is also available. At the end of XV Italian expedition the network covered an area included between the latitude of 71 and 74.5 degrees South and longitude ranging between 160 and 170 degrees East (Capra et al., 2000). Later on, in the frame of the 2000-2001 expedition, the network was extended as far as latitude of 76 degrees South, with the monumentation of the southernmost points. Activities and results of the latter are not reported in this paper. The extension of the monumented network needed of operations carried out both from the research vessel Polar Duke employed by the expedition (points located at north of the 72th south parallel) and from the Italian Mario Zucchelli Station at Terra Nova Bay (all the remaining southern points). This paper deals with the field operations and survey carried out within the joint German-Italian Antarctic expedition 1999-2000 (Mancini, 2001). Results, accuracies, problem related to the reference frame and possibility to detect deformations by further investigation will be discussed. VLNDEF is a project within the activities of GIANT (Geodetic Infrastructure of ANTarctica) SCAR (Scientific Committee on Antarctic Research) programme and is supervised by the SCAR group of specialists of ANTEC (Antarctic NeoTECtonics).
2003
- Caratteristiche geometriche delle immagini EROS
[Relazione in Atti di Convegno]
Mancini, Francesco; Zanni, M.
abstract
na
2003
- Caratteristiche geometriche delle immagini EROS. Esempio di estrazione di un DSM
[Articolo su rivista]
Mancini, Francesco; Zanni, M.
abstract
Tra i sistemi satellitari ad alta risoluzione riveste particolare interesse il sensore presente a bordo del primo, ed attualmente unico, satellite della costellazione EROS. Esso è caratterizzato da una risoluzione geometrica al nadir di 1.8 m, che diventa 2.4 m circa nelle acquisizioni non nadirali. Tali valori sono inferiori a quelli delle immagini fornite da altri sensori ad alta risoluzione (ad esempio Ikonos e QuickBird), ma è prevista la modalità di acquisizione asincrona con prese stereoscopiche eseguite lungo lo stesso segmento di orbita o durante passaggi successivi. Il lavoro analizza le principali proprietà geometriche e radiometriche delle immagini EROS ed affronta il problema dell’estrazione di un modello digitale della superficie fornendo una prima valutazione dell’accuratezza del prodotto ottenuto.
2003
- Geophysical survey at Talos Dome (East Antartica)
[Articolo su rivista]
Frezzotti, M; Bitelli, G; Gandolfi, S; De Michelis, P; Mancini, Francesco; Urbini, S; Vittuari, L; Zirizzotti, A.
abstract
Talos Dome is an ice dome on the edge of the East Antarctic plateau; because accumulation is higher here than in other domes of East Antarctica, the ice preserves a good geochemical and palaeoclimatic record. A new map of the Talos Dome area locates the dome summit using the global positioning system (GPS) (72°47′14″S, 159°04′2″E; 2318.5 m elevation (WGS84)). A surface strain network of nine stakes was measured using GPS. Data indicate that the stake closest to the summit moves south-southeast at a few cm a -1. The other stakes, located 8 km away, move up to 0.33 m a -1. Airborne radar measurements indicate that the bedrock at the Talos Dome summit is about 400 m in elevation, and that it is covered by about 1900 m of ice. Snow radar and GPS surveys show that internal layering is continuous and horizontal in the summit area (15 km radius). The depth distribution analysis of snow radar layers reveals that accumulation decreases downwind of the dome (north-northeast) and increases upwind (south-southwest). The palaeomorphology of the dome has changed during the past 500 years, probably due to variation in spatial distribution of snow accumulation, driven by wind sublimation. In order to calculate a preliminary age vs depth profile for Talos Dome, a simple one-dimensional steady-state model was formulated. This model predicts that the ice 100 m above the bedrock may cover one glacial-interglacial period.
2003
- Il progetto VLNDEF per il monitoraggio delle deformazioni crostali della Terra Vittoria settentrionale.
[Relazione in Atti di Convegno]
Capra, A.; Gandolfi, S.; Mancini, F.; Vittuari, L.; Bitelli, G.; Sarti, P.; Zanutta, A.
abstract
2003
- Immagini ad alta risoluzione e DEM
[Relazione in Atti di Convegno]
Barbarella, M; Mancini, Francesco; Zanni, M.
abstract
na
2003
- Processing of high resolution satellite data for map updating
[Relazione in Atti di Convegno]
Barbarella, M; Mancini, Francesco; Zanni, M.
abstract
The paper addresses the use of high resolution satellite imagery for map updating at technical scale (1:5,000). QuickBird and Ikonos images acquired on a wide portion of the city of Bologna (Italy) were rectified using the available geometric correction models, a Digital Elevation Model of the area and a set of Ground Control Points acquired by GPS survey. Once the reliability of the orthorectification procedure was verified by using a subset of GPS points, an
attempt of features extraction was carried out in order to update entities or thematisms of the present-day cartography. An example relative to the road network updating will be discussed.
2003
- Rectification of high resolution satellite data: evaluating accuracy for map updating
[Relazione in Atti di Convegno]
Barbarella, M; Mancini, Francesco; Zanni, M.
abstract
Since the first commercial high-resolution satellite was launched in the late 1999, the potential of metric accuracy has been widely demonstrated and increased by the 3D imageries offered by sensors such as IKONOS II, EROS and SPOT. This paper addresses the topic of the orthorectification of high resolution satellite data for map updating at scale of up to 1:5,000 and its dependency on DEM accuracy. In order to do so, EROS stereo-imagery, IKONOS II and QuickBird images were acquired over a large portion of the city of Bologna (northern Italy) and its surrounding area. Different orthoimages were generated from IKONOS and QuickBird scenes using DEMs with varying grid spacing and accuracy. Two DEMs were derived from digitalisation of technical maps with grid size of 40 metres and 10 metres respectively, whereas the photogrammetric processing of EROS stereo pair for DEM generation is currently being investigated. The PCI Geomatica software package was used for DEM management and orthorectification. A range of in bundle models is available for orthorectification including rigorous camera and satellite orbital model and rational function model with coefficients computed either from GCPs or metadata provided with the scenes. The accuracy achieved by combining a single satellite image with a DEM was evaluated using an external checkpoint dataset and compared. Thus a large number of Ground Control Points and checkpoints were acquired all over the area by a Real Time Kinematic GPS survey. Overall accuracy and problem encountered during the processing will be discussed.
2003
- Terra Nova Bay GPS permanent station
[Articolo su rivista]
Capra, A.; Gandolfi, S.; Mancini, F.; Negusini, M.; Sarti, P.; Vittuari, L.
abstract
During the IV Italian expedition in Antarctica, the geodetic activity started with the installation of the geodetic network in the area of Terra Nova Bay. The network was established in order to provide a common reference frame to several scientific activities (photogrammetry, cartography, geology) and to study the geodynamics of an area including some interesting tectonic and geologic features. The TNB1 (official name) GPS permanent station was installed during the XIII Italian expedition in 1998, over a granitic hill close to the Italian station of Terra Nova Bay. Following the recommendations for a stable and well-suited site location for the GPS
permanent station a concrete-made pillar was monumented in an area far away from radio frequency disturbs which also guaranteed a complete satellite visibility. The location of the GPS permanent station site with respect to Terra Nova Bay station and a particular of the
monumentation are shown in figure 1.
The geographic location of Terra Nova Bay covered a gap in the distribution of GPS
permanent stations in East Antarctica and, more precisely, along northern Victoria Land. Fifteen GPS permanent stations have been installed in Antarctica until today, and seven of them are IGS (International GPS Service for Geo-dynamics) stations. The non-homogeneous geographic distribution of stations, the long distances
involved and their prevalent settlement on the coastal area leads to some difficulties in a precise satellite ephemeris determination and in GPS data processing for regional geodynamic purposes phenomena with an accuracy at the 5 mm level achieved in static relative positioning.
2003
- Updating Cartography Using Quickbird And Ikonos Ii High Resolution Imagery: Comparison Between Geometric Properties And Accuracy
[Relazione in Atti di Convegno]
Barbarella, M; Mancini, Francesco; Zanni, M.
abstract
The paper addresses the usefulness of high resolution satellite imagery as a support to the updates of local technical cartography (scale 1:5 000). Ikonos II and a recently purchased QuickBird images are available in an area including the downtown of the city of Bologna (Italy) and the surroundings. The paper deals with the data processing performed to obtain, from the satellite images, cartographic products in a well suited reference system. In order to do that, the fulfilling of a preliminary geocoding of the entire dataset is of fundamental importance when geometric distorsions have to be detected. Radiometric quality evaluation and orthorectification of geocoded dataset is subsequently carried out using a Digital Terrain Model (DTM) of the investigated area. DTM allows the reduction of relief effect on planimetric object positioning once the orthorectified images is being processed. Geocoding and orthorectification require a certain number of equally distributed Ground Control Points within the area. They also establish an
external dataset of checkpoints of great usefulness when the final accuracy of geometric correction has to be verified. After rectification and accuracy evaluation procedures the Ikonos II image was selected for the updating of thematic features of technical cartography at 1:5000 scale. Features extraction and geometric/radiometric properties of the images will be discussed in the paper
2002
- Aggiornamento di cartografia tecnica tramite immagini ad alta risoluzione
[Relazione in Atti di Convegno]
Barbarella, M; Mancini, Francesco; Zanni, M.
abstract
L’utilizzo delle immagini IKONOS II pancromatiche per l’aggiornamento della cartografia tecnica è stata ampiamente documentato sin dal rilascio delle prime immagini. Tuttavia la mancanza di un modello rigoroso di orientamento del sensore comporta l’utilizzo di punti di controllo a terra nelle
fasi di georeferenzazione ed ortorettifica. Nella sperimentazione effettuata, relativa all’area a maggior urbanizzazione della Provincia di Bologna, ai fini dell’orientamento dell’immagine è stato eseguito un rilievo GPS in modalità RTK con correzione via GSM. La disponibilità di DEM con maglia di 40 metri ha consentito la generazione dell’ortofoto per l’intera immagine, prodotto di partenza per la successiva fase di aggiornamento di alcune base-dati delle CTR 1:5000 dell’area.
2002
- Elaborazione d’immagini IKONOS su aree in frana. Il caso di Sarno
[Articolo su rivista]
Barbarella, M; Mancini, Francesco; Zanni, M.
abstract
Il lavoro illustra una metodologia operativa che, a partire da un'immagine satellitare ad alta risoluzione (Ikonos II) e da cartografia e modelli digitali del terreno disponibili, consente di eseguire una prima indagine sugli effetti di eventi franosi nella porzione di territorio investigata. Sono discusse le fasi di georeferenziazione ed ortorettifica dell'immagine utilizzata per la creazione di un supporto "cartografico" utile all'estrazione delle informazioni, oltre alle potenzialità offerte nell'ambito dell'aggiornamento della cartografia esistente.
2002
- Geophysical feature of the Mt. Melbourne Area, Antarctica, and preliminary results from the integrated network for monitoring the volcano
[Relazione in Atti di Convegno]
Armadillo, E; Bonaccorso, A; Caneva, G; Capra, Alessandro; Falzone, P; Ferraccioli, F; Mancini, Francesco; Privitera, E; Vittuari, L.
abstract
Geophysical features of the Mt. Melbourne area and first results from the integrated network for monitoring the volcano (Antarctica)
2002
- La rete GPS per il controllo delle deformazioni nell’area di Baia Terra Nova (Antartide)
[Relazione in Atti di Convegno]
Capra, A.; Gandolfi, S.; Mancini, F.; Sarti, P.; Vittuari, L.
abstract
2002
- Metodo GPS e rilievo archeologico. Definizione di una superficie di riferimento per la realizzazione di un GIS su alcuni siti della valle di Chacas (Perù)
[Articolo su rivista]
Capra, Alessandro; Laurencich, L; Mancini, Francesco; Orsini, C.
abstract
The Chacas Valley Project (Dep. of Ancash, Peru), coordinated by Prof. Laurencich Minelli of University of Bologna, is a partnership between the Ministry of Foreign Affairs, the over mentioned University and the Municipality of Chacas. The aim of such project is to carry out an archaeological and anthropological survey on pre-Columbian cultures of the valley. The collected data will be the base for planning some trekking route between the archaeological sites. In lack of sufficiently
detailed maps, it has been necessary to define a cartographic reference system to cover all the investigated area. The knowledge of a detailed topographical surface is also crucial to build up an architectural model of the pre-Columbian urbanized areas. Consequently, the definition of this surface is necessary to locate the architectonic structures and to define their destination of use, and
also to investigate the relationship between the architecture and the morphology of the landscape, a very important element in the urbanization system of pre-Columbian civilizations. Such information
will be obviously of primary importance in order to define some tourist trekking paths between the archaeological zones. This paper introduce the topographic survey carried out in two archaeological
expeditions (1998 and 2000) on the fortified Recuay citadels (II-VI sec. a.d.) Huacramarca and Riway. During the first expedition a traditional methodology has been applied while in the second
one a relative kinematic satellite GPS (Global Positioning System) methodology was employed. The high productivity of the gps methodology allows to acquire many information in short time,
also working in difficult situations (the over mentioned citadels are located at 4000 mt above m.s.l. In a very distant position from the nearest villages). Through gps survey was possible to perform at
the same time a survey to define the position of archaeological structures and the morphology of the landscape. This methodology, which allows the space referencing of all the objects and the
integrated analysis of the information, is a very powerful tool for the interpretation of the sites. The recollected data could constitute the first step towards the realization of a gis for the cultural heritage valorization of this area, and offer a research opportunity for archaeologist to gather geo-morphological information together with all the other data available from different source of observation.
2002
- Multidisciplinary approach for archaeological survey: exploring GPS method for space related interpretation
[Articolo su rivista]
Capra, Alessandro; Gandolfi, S; Laurencich, L; Mancini, Francesco; Minelli, A; Orsini, C; Rodriguez, Ar
abstract
Started in 1996, the Chacas Valley Project is coordinated by Laura Laurencich Minelli and aims to study the social–cultural organization
of space in the Chacas Region (Ancash-Perú) during the Early Intermediate Period (III–VII century A.D.). For an anthropological
interpretation of ancient urbanized territory, a multidisciplinary approach focused on gathering both archeological data and topographical information is necessary. The kinematic GPS method has been applied in order to reach the needed accuracy in representing the geometric properties of the objects, to preserve the geometric properties between the structures and to document the relations with the ground morphological aspects.
2002
- Paesaggio e rappresentazione di aree archeologiche in una valle andina (Chacas – Perù)
[Relazione in Atti di Convegno]
Mancini, Francesco; Orsini, C; Stefani, M.
abstract
Il lavoro illustra alcuni dei risultati ottenuti durante i rilievi archeologici eseguiti nell'area della Valle di Chacas (Ancash- Perù) a partire dal 1996. Nel contesto di tali studi, al tradizionale rilievo è stato associato il rilievo topografico e fotogrammetrico delle strutture presenti volto anche a rappresentare i principali caratteri morfologici dell'area. L'analisi integrata delle informazioni raccolte consente da una parte di documentare i resti degli insediamenti e gli oggetti rinvenuti attraverso tecniche topografiche rigorose e dall'altra di indagare il rapporto esistente tra uomo e ambiente nelle aree andine in funzione dei diversi piani ecologici individuati.
2002
- Rilievo di punti fiduciali catastali con tecniche RTK
[Relazione in Atti di Convegno]
Barbarella, M; Dubbini, M; Gandolfi, S; Gordini, C; Lenzi, V; Mancini, Francesco; Zanni, M.
abstract
La sperimentazione eseguita su un poligono caratterizzato da una zona di insediamento industriale e da una densamente urbanizzata, di estensione totale di 3x1 Km2, riguarda la determinazione di punti fiduciali catastali tramite varie metodologie: GPS statico e intersezione in avanti con stazione totale,
GPS-RTK con Radio Modem e GSM integrati da misure di distanze e/o allineamenti. Nella nota vengono fatte considerazioni tanto sul rilievo diretto GPS dei punti prossimi "ex centro" quanto sulla determinazione “indiretta”di PF catastali a partire dalle misure dirette dei punti prossimi (excentro).
2002
- Utilizzazione di immagini satellitari ad alta risoluzione a fini cartografici
[Relazione in Atti di Convegno]
Radicioni, F; Grassi, S; Mancini, Francesco
abstract
Le tradizionali metodologie di aggiornamento e produzione di cartografica si basano, come è noto, sulle informazioni provenienti dalla fotogrammetria aerea: solo da pochi anni sono disponibili immagini digitali ad alta risoluzione acquisite da satelliti commerciali dei quali si riportano le principali
caratteristiche. L’utilizzo a fini cartografici di tali immagini richiede la definizione di modelli funzionali per il passaggio tra lo spazio immagine e lo spazio oggetto. Dapprima verranno descritte le più significative metodologie per la correzione delle distorsioni geometriche delle immagini e successivamente verranno applicate a differenti scene IKONOS. La qualità metrica del prodotto finale, ovvero l’ortofotoproiezione, è influenzata in maniera significativa dalla natura e dall’accuratezza dei GCP oltre che dalle caratteristiche del DTM e dalla morfologia del terreno.
2001
- GPS cinematico per il monitoraggio della topografia dell'area di Dome C (Antartide)
[Relazione in Atti di Convegno]
Gandolfi, S; Mancini, Francesco
abstract
Nell’ambito del progetto denominato EPICA (European Project for Ice Core in Antartica), durante la campagna di ricerche in Antartide del 1995/1996, fu istituita e misurata per la prima volta una rete GPS statica finalizzata al controllo delle deformazioni superficiali di un’area del Plateau Antartico a forma di duomo, denominata Dome C, considerata idonea alla realizzazione di un carotaggio profondo per studi paleoclimatici. Il rilievo in modalità statica è stato ripetuto nella campagna antartica dell'anno 1998/1999 ed in entrambe sono stai tacquisiti anche numerosi profili cinematici che elaborati in post-processamento hanno consentito la ricostruzione della superficie topografica relativi ai due periodi di misura a corredo delle informazioni sulle deformazioni locali ricavate dall'analisi delle misure statiche. Nel lavoro vengono discusse le procedure relative al confronto dei DTM per la stima dell'accumulo nevoso sul duomo e delle problematiche annesse, sempre in riferimento all'ambiente particolare in cui è condotta la sperimentazione .
2001
- Il controllo delle deformazioni nell’area geotermica di Travale
[Relazione in Atti di Convegno]
Capra, Alessandro; Gandolfi, S; Mancini, Francesco; Rossi, A; Vittuari, L.
abstract
Il controllo delle deformazioni nell’area geotermica di Travale
2001
- La geomatica per il monitoraggio ambientale negli studi ecofisiologici di specie antartiche
[Relazione in Atti di Convegno]
Bitelli, G; Mancini, Francesco; Vittuari, L.
abstract
Il lavoro illustra alcune applicazioni delle tecniche geomatiche a supporto di programmi di ricerca avviati da tempo nell'ambito di studi nelle discipline biologiche per la caratterizzazione di alcune comunità di pinguini situate nell'area di Edmonson Point nella Terra Vittoria Settentrionale (Antartide). Il supporto della geomatica in questo caso ha il duplice scopo di fornire uno strumento utile alla quantificazione dei molteplici parametri che contribuiscono alla definizione dell'ecofisiologia di queste specie e di raccogliere in modo produttivo e non invasivo informazioni in un ambiente dove tutte le operazioni sono rese difficoltose dalle condizioni ambientali. In particolare saranno descritti i risultati ottenuti attraverso il rilievo GPS cinematico e l'analisi di immagini aeree.
2001
- VLNDEF project: geodetic contribution to geodynamics study of Victoria Land, Antarctica
[Capitolo/Saggio]
Capra, Alessandro; Gandolfi, S; Mancini, Francesco; Sarti, S; Vittuari, L.
abstract
NA
2000
- Geodetic activities during the GANOVEX VIII: a new GPS network for crustal deformation control in North Victoria Land
[Articolo su rivista]
Mancini, Francesco
abstract
Report on the monumentation of a new geodetic infrastructure in Antarctica
2000
- Il telerilevamento per la conoscenza e la pianificazione del territorio urbanizzato
[Articolo su rivista]
Capra, Alessandro; Mancini, Francesco
abstract
Sulle applicazioni delle emergenti tecniche di telerilevamento satellitare all'urbanistica.
2000
- Rilievo e rappresentazione di siti archeologici: l'isola di Nelson (Alessandria, Egitto)
[Relazione in Atti di Convegno]
Capra, Alessandro; Mancini, Francesco; Tini, M. A.
abstract
Rilievo e rappresentazione di siti archeologici: l'isola di Nelson (Alessandria, Egitto)
1999
- Verso il monitoraggio ambientale dell’Antartide su scala globale. Il progetto VECTRA
[Relazione in Atti di Convegno]
Capra, Alessandro; Coren, F; Frezzotti, M; Mancini, Francesco; Sterzai, P; Vidmar, R.
abstract
Verso il monitoraggio ambientale dell’Antartide su scala globale. Il progetto VECTRA.
1998
- Comparison between TEC values derived from antarctic GPS measurements and atmospheric soundings
[Articolo su rivista]
Al Bayari, O; Capra, Alessandro; Mancini, Francesco; Vittuari, L.
abstract
Ionospheric refraction introduces a delaying effect on GPS observables (code and carrier phase measurements) and therefore on the precise relative position derived. This cannot be completely solved by GPS dual frequency techniques that only take into account the geometric effect of the ionosphere (first order approximation; Ciraolo, 1994) considered as an undisturbed region associated with a constant vertical gradient of Total Electron Content TEC (Menge, 1996). Non-geometric effects also play a fundamental role in signal-ionosphere interactions mainly in equatorial and auroral regions (such as Antarctica) where the severe ionospheric conditions influence the GPS signals (scintillation phenomena). In an attempt to understand and model this effect, we computed the TEC values from selected 1993 GPS Antarctic dataset, using different GPS-based methods. Finally we compared the GPS-derived TEC values with those computed with the ionospheric model based on atmospheric soundings, performed
simultaneously to the GPS measurements and in the same region (Terra Nova Bay, Antarctica) by a researcher from the Istituto Nazionale di Geofisica (Rome). The TEC values from GPS observables and atmospheric soundings showed good agreement, taking into account the extreme variability of the phenomenon investigated and the strong dependence on satellite orbital parameters (elevation and azimuth).
1998
- GPS for ice sheets movement monitoring and grounding line detection
[Capitolo/Saggio]
Capra, Alessandro; Frezzotti, M; Mancini, Francesco; Radicioni, F; Vittuari, L.
abstract
Use of static and kinematic GPS for the determination of ice sheets movement and for the gounding line detection.
1997
- Coastal defence by breakwaters and sea level rise: the case of the Italian Northern Adriatic Sea
[Capitolo/Saggio]
Colantoni, P; Gabbianelli, G; Mancini, Francesco; Bertoni, W.
abstract
Le littoral de la mer Adriatique nord-occidentale, depuis Monfalcone jusqu'à Cattolica, est bas et sableux, exposé à un affaissement naturel et anthropique, notamment dans la région de Venise, Delta du Pô, et de Ravenna. L'érosion provoquée - ou aggravée - par les activités humaines a d'abord été combattue par des barrages perpendiculaires à la côte, ensuite par des brise-lames parallèles à celle-ci, qui toutefois ont souvent entraîné des conséquences négatives. Récemment, on a préféré la reconstitution artificielle protégée par des structures immergées afin de limiter la perte de sable. Les changements du niveau de la mer provoqués par l'eustatisme et par la subsidence entraîneront un déplacement de la ligne côtière qui est estimé ici sur la base de modèles numériques prévisionnels.