Applied Geomatics 

About: Applied Geomatics is an academic journal published by Springer Science+Business Media. The journal publishes majorly in the area(s): Land cover & Land use. It has an ISSN identifier of 1866-928X. Over the lifetime, 495 publications have been published receiving 6420 citations.

UAV for 3D mapping applications: a review

Abstract: Unmanned aerial vehicle (UAV) platforms are nowadays a valuable source of data for inspection, surveillance, mapping, and 3D modeling issues. As UAVs can be considered as a low-cost alternative to the classical manned aerial photogrammetry, new applications in the short- and close-range domain are introduced. Rotary or fixed-wing UAVs, capable of performing the photogrammetric data acquisition with amateur or SLR digital cameras, can fly in manual, semiautomated, and autonomous modes. Following a typical photogrammetric workflow, 3D results like digital surface or terrain models, contours, textured 3D models, vector information, etc. can be produced, even on large areas. The paper reports the state of the art of UAV for geomatics applications, giving an overview of different UAV platforms, applications, and case studies, showing also the latest developments of UAV image processing. New perspectives are also addressed.

Reality-based 3D documentation of natural and cultural heritage sites—techniques, problems, and examples

Abstract: The importance of cultural and natural heritage documentation is well recognized at international level, and there is an increasing pressure to document and preserve heritage also digitally. The continuous development of new sensors, data capture methodologies, and multi-resolution 3D representations and the improvement of existing ones can contribute significantly to the 3D documentation, conservation, and digital presentation of heritages and to the growth of the research in this field. The article reviews some important documentation requirements and specifications, the actual 3D surveying and modeling techniques and methodologies with their limitations and potentialities as well some visualization issues involved in the heritage field. Some examples of world heritage sites 3D documentation are reported and discussed.

Use of geospatial data and fuzzy algebraic operators to landslide-hazard mapping

Abstract: Geospatial data base creation for landslide-hazard mapping is often an almost inhibitive activity. This has been the reason that for quite some time landslide-hazard analysis was modeled on the basis of spatially related factors. This paper presents the use of fuzzy logic to landslide-hazard analysis in the Penang Island, Malaysia, using remote sensing data and a geographic information system (GIS). To achieve the goal, a data-derived model (frequency ratio) and a knowledge-derived model (fuzzy operator) were combined for landslide-hazard analysis. Landslide locations within the study areas were identified by interpreting aerial photographs, satellite images and field surveys. The nine factors that influence landslide occurrence were extracted from the database and the frequency ratio coefficient for each factor was computed. Using the factors and the identified landslide, the fuzzy membership values were calculated. Then fuzzy algebraic operators were applied to the fuzzy membership values for landslide-hazard mapping. Finally, the produced map was verified by comparing with existing landslide locations for calculating prediction accuracy. Among the fuzzy operators, in the case in which the gamma operator (λ = 0.8) showed the best accuracy (80%) while the case in which the fuzzy or operator was applied showed the worst accuracy (56%).

Generative HBIM modelling to embody complexity (LOD, LOG, LOA, LOI): surveying, preservation, site intervention—the Basilica di Collemaggio (L’Aquila)

Abstract: In December 2012, EniServizi (the Italian multinational energy company), after the Earthquake that occurred at L’Aquila in April 2009, decided to undertake the project “Re-start from Collemaggio”, funding around 14 million Euro to restore the Basilica di Collemaggio EniServizi, aware of the BIM potential role in the complex building and infrastructure domain in the world, required an advanced HBIM based on laser scanner and photogrammetric surveying to address decision-making processes among the different actors involved in the preservation process The Basilica of Collemaggio has been re-opened to the public on December 2017 This paper tries to make a synthesis of the different lessons learnt, in relation to both positive and critical aspects relating HBIM feasibility, sustainability and usefulness to the challenging restoration and preservation field The theoretical and practical HBIM approach here tackled overcomes the current BIM logic based on the sequential process adopted by the AIA and NBS Level of Development (LOD), characterized by a simple-to-complex-detailing process, working in the new construction domain and generally following the conceptualizing phase, the preliminary design, the executive design, the construction phase till to the facility management A complex-mixed LOD approach, able to entail the richness, unicity and multiplicity of each component and to get the maximum degree of knowledge, has been experimented in order to derive informed decisions in terms of preservation, restoration and management since the starting phases of the architectural design To this aim, a Level of Geometry (LOG) coherent to the Level of Accuracy gained by the high-resolution surveys has been adapted to the specificity of the restoration process of a historic monument and is here proposed through different Grade of Generation (GOG) protocols developed in the object modelling to support the preliminary and definitive design proposal of the conservation plan of the Basilica Particularly, a NURBS-based parametric generative modelling process (GOG9-10) is here proposed in order to get models “BIM abled” to describe the complex geometry and to match the related information Specific Level of Information (LOI) has been introduced to support the preservation process, to document the as-built and the management of the building after the intervention, moving HBIM toward multi-actor domain Given the effort required by such approach, obtaining a cost-effective HBIM modelling embodying the complexity of each damaged element as acquired by the surveys (ie walls, pillars, vaults, beams) represents a challenging issue The result of the overall process aims to contribute in lowering the initial HBIM modelling costs by deploying a sustainable complexity delivering protocols and specification and by boosting at the same time an interoperable cooperative HBIM habit among multi-actors across all the phases, spreading its usability after the restoration process On the lesson learnt, the process of updating the current Codification criteria (UNI11337-2009) has been started with a draft proposal stimulating the debate for the future of HBIM adoption in the case of restoration, preservation and maintenance (UNI11337-2017): in the conviction that transferring the HBIM richness into the Life Cycle Management process will allow multi-actors to take in account the knowledge and information gained during the restoration, integrating the as-built updating and keeping updated the monument monitoring during the time being

UAV monitoring and documentation of a large landslide

Abstract: In June 2013, heavy precipitation triggered a large earthflow of several million cubic meters in a small village in Austria. A bundle of technologies was applied to monitor and document the landslide, such as geophysical methods (geoelectrics, inclinometer, soil moisture, and soil temperature) and Global Navigation Satellite System (GNSS) measurements. Additionally, an Unmanned Aerial Vehicle (UAV) was used for the periodical assessment of the landslide process. In total, nine flights were performed with a multicopter equipped with a digital single-lens reflex camera (DSLR) that delivered several thousands of images. Based on these images and detailed GNSS measurements of the landslide area, orthophotos as well as generated Digital Surface Models (DSMs) with an accuracy of less than ±10 cm resulted. Fissure tracking, flow direction and velocity, and mass balances as well as the construction progress of the protection and mitigation measures were derived from these data sets. The application of the UAV turned out to be a cost- and time-effective tool for landslide-monitoring that provides researchers and engineers with accurate high-resolution geodata.