scholarly journals UAV Photogrammetry and Ground Surveys as a Mapping Tool for Quickly Monitoring Shoreline and Beach Changes

2020 ◽  
Vol 8 (1) ◽  
pp. 52 ◽  
Author(s):  
Antonio Zanutta ◽  
Alessandro Lambertini ◽  
Luca Vittuari
Keyword(s):  
Morphological Changes ◽  
Three Dimensional ◽  
Temporal Analysis ◽  
Anthropogenic Factors ◽  
Engineering Structures ◽  
Northern Adriatic ◽  
Mapping Tool ◽  
Multi Temporal ◽  
Maintenance Work ◽  
Three Dimensional Models

The aim of this work is to evaluate UAV photogrammetric and GNSS techniques to investigate coastal zone morphological changes due to both natural and anthropogenic factors. Monitoring morphological beach change and coastline evolution trends is necessary to plan efficient maintenance work, sand refill and engineering structures to avoid coastal drift. The test area is located on the Northern Adriatic coast, a few kilometres from Ravenna (Italy). Three multi-temporal UAV surveys were performed using UAVs supported by GCPs, and Post Processed Kinematic (PPK) surveys were carried out to produce three-dimensional models to be used for comparison and validation. The statistical method based on Crossover Error Analysis was used to assess the empirical accuracy of the PPK surveys. GNSS surveys were then adopted to evaluate the accuracy of the 2019 photogrammetric DTMs. A multi-temporal analysis was carried out by gathering LiDAR dataset (2013) provided by the “Ministero dell’Ambiente e della Tutela del Territorio e del Mare” (MATTM), 1:5000 Regional Technical Cartography (CTR, 1998; DBTR 2013), and 1:5000 AGEA orthophotos (2008, 2011). The digitization of shoreline position on multi-temporal orthophotos and maps, together with DTM comparison, permitted historical coastal changes to be highlighted.

There-dimensional change detection in coastal cliffs using UAV and TLS

2020 ◽  
Author(s):  
Yuichi S. Hayakawa ◽  
Hiroyuki Obanawa
Keyword(s):  
Point Cloud ◽  
Morphological Changes ◽  
Three Dimensional ◽  
Dimensional Change ◽  
Point Clouds ◽  
Temporal Analysis ◽  
Small Island ◽  
Cloud Data ◽  
Tidal Waves ◽  
Coastal Cliffs

<p>Measuring three-dimensional morphological changes in rocky coasts is essential in protecting the </p><p>coastal areas and evaluating the sediment dynamics therein. In this study, we carried out repeated </p><p>measurements of the three-dimensional morphology of a small rocky island using terrestrial laser </p><p>scanning (TLS) and unmanned aerial vehicle (UAV)-based structure-from-motion (SfM) </p><p>photogrammetry for 5 years. The TLS-derived point cloud data is used to align the UAV-SfM point </p><p>cloud with a better accuracy at a centimeters scale, for which iterative closest point (ICP) method was </p><p>applied. Aligned UAV-derived point clouds were then compared each other to extract changed mass </p><p>for each time period. The extracted point cloud of changed mass was converted to 3D mesh polygons, </p><p>by which the total volume of eroded mass was calculated.</p><p>The temporal analysis of the point cloud revealed spatially variable rockfalls and wave cuts. The </p><p>eroded mass volume for each period varied from 10.6 to 527.7 m3, which is equivalent to the horizontal </p><p>erosion rates of 0.03 to 0.63 m/y. The temporal changes in the eroded volume is roughly associated </p><p>with that in the frequency of high tidal waves (higher than 3 m) observed in this area. However, less </p><p>correlation was found with the frequency of large ground shakes by earthquakes. The modern erosion </p><p>rate is lower than the previously reported cliff retreat rates, but this suggests that the small island will </p><p>disappear in decades. Three-dimensional structural analysis will also help understand the dynamic </p><p>processes of the erosion of the bedrock cliffs in the island.</p>

scholarly journals Morphological Changes Detection of a Large Earthflow Using Archived Images, LiDAR-Derived DTM, and UAV-Based Remote Sensing

2020 ◽  
Vol 13 (1) ◽  
pp. 120
Author(s):  
Massimo Conforti ◽  
Michele Mercuri ◽  
Luigi Borrelli
Keyword(s):  
Morphological Changes ◽  
Source Area ◽  
Temporal Analysis ◽  
Earth Satellite ◽  
Google Earth ◽  
Aerial Photographs ◽  
Temporal Data ◽  
Transport Zone ◽  
Multi Temporal ◽  
System Data

In mountainous landscapes, where strongly deformed pelitic sediments outcrop, earthflows can dominate denudation processes and landscape evolution. This paper investigated geological and geomorphological features and space-time evolution over a 65-year time span (1954–2019) of a large earthflow, representative of wide sectors of the Apennine chain of southern Italy. The landslide, with a maximum length of 1.85 × 103 m, affects an area of 4.21 × 105 m2 and exhibits two source zones: a narrow and elongated transport zone and a lobate accumulation zone. Spatial and temporal morphological changes of the earthflow were assessed, comparing multi-source and multi-temporal data (aerial photographs, Google Earth satellite images, Light Detection and Ranging (LiDAR) and Unmanned Aerial Vehicles (UAV) system data). Geomorphic changes, quantified using Digital Terrain Models (DTMs) of differences, highlighted an extensive lowering of the topographic surface in the source area and a significant uplift at the landslide toe. Moreover, the multi-temporal analysis showed a high increase of landslide surface (more than 66%) during the last 65 years. The volumetric analyses showed that different sectors of the earthflow were active at different times, with different rates of topographic change. Overall, the used approach highlighted the great potentiality of the integration of multi-source and multi-temporal data for the diachronic reconstruction of morphological landslide evolution.

scholarly journals Spatio-temporal analysis of short-term rainfall extremes in Croatia

2021 ◽  
Author(s):  
Ksenija Cindric Kalin ◽  
Irena Nimac ◽  
Leonardo Patalen ◽  
Zoran Pasaric
Keyword(s):  
Warning System ◽  
Temporal Analysis ◽  
Precipitation Extremes ◽  
Short Term ◽  
Regional Variability ◽  
Rainfall Thresholds ◽  
Engineering Structures ◽  
Extreme Rainfall Events ◽  
Northern Adriatic ◽  
Rainfall Extremes

<p><span>Extreme rainfall events of short duration and their possible intensification in the future may induce large implications in the existing engineering structures and water risk assessment. In Croatia, the sub-daily time scale (6 hours and 12 hours) is used to select an appropriate threshold value to define yellow, green and red alarming categories in the Meteoalarm rainfall warning system. The study aims i</span><span>) </span><span>to </span><span>provide the general climatology of short-rainfall extremes to analyse regional variability in precipitation extremes, and ii) to </span><span>update the alarming rainfall thresholds in Croatia and to upgrade the alarming system from regional (presently 8 regions) to the county level (21 counties). The short-term (from 5 minutes to one hour) and sub-daily (from 2 to 24 hours) precipitation amounts are analysed in terms of their spatial and temporal characteristics. The study comprises the ombrographic station network of 56 stations, evenly distributed over Croatia, with datasets covering the period 1961-2019. For each duration, the Generalized Extreme Value (GEV) distribution is fitted to the annual-maxima precipitation amounts, employing both the stationary and non-stationary model. Spatial distribution of the corresponding 2, 5, 10, 25, 50 and 100 years return values shows a clear distinction between the continental and maritime regions for each duration of rainfall with a pronounced maximum in the northern Adriatic (Kvarner) region. The implications on the current rainfall thresholds in the alarming system and new proposals will be discussed. Additionally, the </span><span>changes in characteristics of short-term precipitation extremes will be presented providing the climatological background for climate change adaptation activities and impact assessment in Croatia.</span></p>

scholarly journals DEVELOPMENT AND IMPLEMENTATION OF INNOVATIVE EDUCATIONAL MODULES ON ARCHITECTURAL PHOTOGRAMMETRY FOR BACHELOR’S DEGREE CURRICULA IN ARCHITECTURE

2019 ◽  
Vol XLII-5/W3 ◽  
pp. 115-120
Author(s):  
R. Shults
Keyword(s):  
Architectural Design ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Engineering Structures ◽  
Design Problems ◽  
Close Range ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
Key Participants ◽  
Educational Modules

Abstract. Modern specialists in the field of architecture work exclusively in three-dimensional space. At the same time, their training completely ignores the state-of-the-art technologies associated with obtaining three-dimensional models of engineering structures. In such circumstances, the connections between the three key participants in the design and construction of engineering structures, namely architects, builders, and surveyors are broken. The main technology that allows obtaining three-dimensional models is photogrammetry. The purpose of the presented article is to determine the subject matter of close-range photogrammetry in solving architectural design problems. Based on certain architectural tasks, educational modules for the discipline of architectural photogrammetry of the bachelor educational level were developed. The peculiarity of the proposed program is that it is designed in such a way that it allows using the whole complex of the modern achievements in the field of automated image processing and the specifics of setting and solving architectural problems. At the same time, this program covers such modern technologies and concepts as UAV photogrammetry, digital photogrammetry, photogrammetric scanning, BIM, GIS, etc. Such an approach allows students without problems to learn several special knowledge, which is owned by surveyors and photogrammetrists. The approximate content of the course of architectural photogrammetry for bachelor students is presented.

scholarly journals Dynamic structural parameters verification on the example of theoretical analysis and in situ tests of suspension footbridge

2019 ◽  
Vol 262 ◽  
pp. 10007
Author(s):  
Michał Jukowski ◽  
Ewa Błazik-Borowa ◽  
Jarosław Bęc ◽  
Janusz Bohatkiewicz
Keyword(s):  
Structural Parameters ◽  
Rapid Development ◽  
Three Dimensional ◽  
Nonlinear Material ◽  
Structural Elements ◽  
In Situ Tests ◽  
Engineering Structures ◽  
Material Models ◽  
Three Dimensional Models

The 21st century is a period of rapid development of computer technology, which allowed designers to create complex, three-dimensional models of engineering structures. Thanks to these solutions, it is possible to perform complex analyses, for example modal or dynamic ones of cable-stayed or suspension structures. For such objects, verification of the correct work of structural elements takes place in the field of non-linear analysis. The presented paper is an example of a comparative analysis concerning modal and static analysis - Natural Frequency with Nonlinear Material Models and Static Stress with Nonlinear Material Models, carried out in the Autodesk Simulation Multiphysics program with dynamic in situ tests of a suspension footbridge. The main purpose of the research was to evaluate the value of pre-tension forces in the cables of the load-bearing structure.

Plastic replicas as three-dimensional models of pulps

1975 ◽  
Vol 39 (8) ◽  
pp. 544-546
Author(s):  
HL Wakkerman ◽  
GS The ◽  
AJ Spanauf
Keyword(s):  
Three Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models

Validation of a Belt Model for Prediction of Hub Forces from a Rolling Tire4

2009 ◽  
Vol 37 (2) ◽  
pp. 62-102 ◽  
Author(s):  
C. Lecomte ◽  
W. R. Graham ◽  
D. J. O’Boy
Keyword(s):  
Internal Pressure ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Prediction Method ◽  
Analytical Models ◽  
Beam Model ◽  
Impedance Boundary ◽  
Bending Waves ◽  
Tire Rotation ◽  
Three Dimensional Models

Abstract An integrated model is under development which will be able to predict the interior noise due to the vibrations of a rolling tire structurally transmitted to the hub of a vehicle. Here, the tire belt model used as part of this prediction method is first briefly presented and discussed, and it is then compared to other models available in the literature. This component will be linked to the tread blocks through normal and tangential forces and to the sidewalls through impedance boundary conditions. The tire belt is modeled as an orthotropic cylindrical ring of negligible thickness with rotational effects, internal pressure, and prestresses included. The associated equations of motion are derived by a variational approach and are investigated for both unforced and forced motions. The model supports extensional and bending waves, which are believed to be the important features to correctly predict the hub forces in the midfrequency (50–500 Hz) range of interest. The predicted waves and forced responses of a benchmark structure are compared to the predictions of several alternative analytical models: two three dimensional models that can support multiple isotropic layers, one of these models include curvature and the other one is flat; a one-dimensional beam model which does not consider axial variations; and several shell models. Finally, the effects of internal pressure, prestress, curvature, and tire rotation on free waves are discussed.

Thermal characterization of ABS-Graphene blended three dimensional printed functional prototypes for electro chemical energy storage

2018 ◽  
Vol 1 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Kamaljit Singh Boparai ◽  
Rupinder Singh
Keyword(s):  
Energy Storage ◽  
Structural Changes ◽  
Fused Deposition Modeling ◽  
Morphological Changes ◽  
Three Dimensional ◽  
Thermal Characterization ◽  
Chemical Energy ◽  
Flow Index ◽  
Fused Deposition

This study highlights the thermal characterization of ABS-Graphene blended three dimensional (3D) printed functional prototypes by fused deposition modeling (FDM) process. These functional prototypes have some applications as electro-chemical energy storage devices (EESD). Initially, the suitability of ABS-Graphene composite material for FDM applications has been examined by melt flow index (MFI) test. After establishing MFI, the feedstock filament for FDM has been prepared by an extrusion process. The fabricated filament has been used for printing 3D functional prototypes for printing of in-house EESD. The differential scanning calorimeter (DSC) analysis was conducted to understand the effect on glass transition temperature with the inclusion of Graphene (Gr) particles. It has been observed that the reinforced Gr particles act as a thermal reservoir (sink) and enhances its thermal/electrical conductivity. Also, FT-IR spectra realized the structural changes with the inclusion of Gr in ABS matrix. The results are supported by scanning electron microscopy (SEM) based micrographs for understanding the morphological changes.

In Silico Identification and Molecular Characterization of Extracellular Cathepsin L Proteases from Giardia duodenalis

2020 ◽  
Vol 17 (4) ◽  
pp. 342-351
Author(s):  
Sergio A. Durán-Pérez ◽  
José G. Rendón-Maldonado ◽  
Lucio de Jesús Hernandez-Diaz ◽  
Annete I. Apodaca-Medina ◽  
Maribel Jiménez-Edeza ◽  
...  
Keyword(s):  
In Silico ◽  
Cathepsin L ◽  
Three Dimensional ◽  
Giardia Duodenalis ◽  
Evolutionary Genetics ◽  
Extracellular Proteins ◽  
In Silico Identification ◽  
Dimensional Models ◽  
Three Dimensional Models

Background: The protozoan Giardia duodenalis, which causes giardiasis, is an intestinal parasite that commonly affects humans, mainly pre-school children. Although there are asymptomatic cases, the main clinical features are chronic and acute diarrhea, nausea, abdominal pain, and malabsorption syndrome. Little is currently known about the virulence of the parasite, but some cases of chronic gastrointestinal alterations post-infection have been reported even when the infection was asymptomatic, suggesting that the cathepsin L proteases of the parasite may be involved in the damage at the level of the gastrointestinal mucosa. Objective: The aim of this study was the in silico identification and characterization of extracellular cathepsin L proteases in the proteome of G. duodenalis. Methods: The NP_001903 sequence of cathepsin L protease from Homo sapienswas searched against the Giardia duodenalisproteome. The subcellular localization of Giardia duodenaliscathepsin L proteases was performed in the DeepLoc-1.0 server. The construction of a phylogenetic tree of the extracellular proteins was carried out using the Molecular Evolutionary Genetics Analysis software (MEGA X). The Robetta server was used for the construction of the three-dimensional models. The search for possible inhibitors of the extracellular cathepsin L proteases of Giardia duodenaliswas performed by entering the three-dimensional structures in the FINDSITEcomb drug discovery tool. Results: Based on the amino acid sequence of cathepsin L from Homo sapiens, 8 protein sequences were identified that have in their modular structure the Pept_C1A domain characteristic of cathepsins and two of these proteins (XP_001704423 and XP_001704424) are located extracellularly. Threedimensional models were designed for both extracellular proteins and several inhibitory ligands with a score greater than 0.9 were identified. In vitrostudies are required to corroborate if these two extracellular proteins play a role in the virulence of Giardia duodenalisand to discover ligands that may be useful as therapeutic targets that interfere in the mechanism of pathogenesis generated by the parasite. Conclusion: In silicoanalysis identified two proteins in the Giardia duodenalisprotein repertoire whose characteristics allowed them to be classified as cathepsin L proteases, which may be secreted into the extracellular medium to act as virulence factors. Three-dimensional models of both proteins allowed the identification of inhibitory ligands with a high score. The results suggest that administration of those compounds might be used to block the endopeptidase activity of the extracellular cathepsin L proteases, interfering with the mechanisms of pathogenesis of the protozoan parasite Giardia duodenalis.

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