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Application of a 3D laser scanner in the assessment of erosion and deposition volumes and channel change in a proglacial river

Application of a 3D laser scanner in the assessment of erosion and deposition volumes and channel change in a proglacial river
This study reports the use of a high-resolution 3D laser scanner in the assessment of erosion and deposition volumes in the proglacial zone of Glacier du Ferpècle and Mont Miné, Switzerland. High-resolution data obtained across a braid plain during

3D model-based estimations of volume and mass of high-energy dislocated boulders in coastal areas of Greece by terrestrial laser scanning

3D model-based estimations of volume and mass of high-energy dislocated boulders in coastal areas of Greece by terrestrial laser scanning
Boulder ; Coastal dynamics ; Coastal environment ; Dislocation ; Greece ; Model ; Peloponnese ; Research technique ; Terrestrial laser scanning ; Wave
Boulders of 2 coastal areas (Cape Skalas in southern Lakonia, Peloponnese; Cape Gerogombos on Paliki Peninsula in western Greece were surveyed within their topographical context using a laser scanner in combination with a DGPS. 3D reconstruction
allows the determination of highly accurate volumetric data, as well as the extraction of further parameters, such as elevation above sea level, inclination and distance to the sea for each boulder. The results show that terrestrial laser scanning
in combination with DGPS is capable to derive reliable parameters for wave transport equations. The combination of 3D model-based volume estimations and density measurements provide a better accuracy than achieved by conventional approximations, which are still

Roof type determination from a sparse laser scanning point cloud

Roof type determination from a sparse laser scanning point cloud
3D scanner ; Brno ; Building ; Czech Republic ; Digital elevation model ; Model ; Roof ; Town ; laser measures
Brno ; Bâtiment ; Mesure laser ; Modèle ; Modèle numérique de terrain ; Pardubice ; Scanner tridimensionnel ; Sobotka ; Tchèque république ; Toit ; Ville
A method for determining a roof coverage type and a building height from a sparse laser scanning point cloud was introduced in Hofman (2008). A new model driven method is presented, which is suitable for buildings with a rectangular plot. Based

Using 3D photo-reconstruction methods to estimate gully headcut erosion

Using 3D photo-reconstruction methods to estimate gully headcut erosion
Data processing ; Digital elevation model ; Earth surface processes ; Erosion rate ; Experimental catchment ; Gully erosion ; Methodology ; Photography ; Spain ; Terrestrial laser scanning ; Watershed
in the Parapuños experimental catchment, SW Spain : 2 headcuts located along the channel and 3 lateral-bank headcuts. Firstly, the accuracy of the resulting models was tested using as benchmark a 3D model obtained by means of a Terrestrial Laser Scanner (TLS
Three-dimensional photo-reconstruction methods (3D-PR) based on Structure from Motion (SfM) and MultiView-Stereo (MVS) techniques are tested for estimating the volume of gully headcut retreat. The study was carried out using 5 small headcuts
in gully heads. It is concluded that 3D-PR techniques showed a great potential for studying detailed geomorphic changes.

Using geomorphological and geophysical survey to research relations between landforms and joint tectonics in the Broumovská vrchovina (Czech Republic)

3D scanner ; Bohemian Massif ; Carboniferous ; Cretaceous ; Czech Republic ; Earthquake ; Fault ; Fracture ; Geomorphology ; Joint ; Landform evolution ; Lineament ; Lithology ; Palaeogeography ; Sedimentary sequence ; Tectonics
Carbonifère ; Crétacé ; Diaclase ; Evolution du relief ; Faille ; Fracture ; Géomorphologie ; Linéament ; Lithologie ; Paléogéographie ; Scanner tridimensionnel ; Séisme ; Séquence sédimentaire ; Tchèque république ; Tectonique ; Česká vysočina
Cretaceous and Permo-Carboniferous sedimentary series. They examine joint orientation using field measurements and 3D seismic tomography. The orientation of linear topographic features (morpholineaments) shows a clear dependency on two perpendicular joint

Terrestrial laser scanning of rock slope instabilities

Terrestrial laser scanning of rock slope instabilities
Forecast ; Landslide ; LiDAR ; Mass movement ; Remote sensing ; Research technique ; Rockfall ; Slope ; Terrestrial laser scanning
Key insights into the use of terrestrial laser scanning (TLS) in rock slope investigations include : 1) the capability of remotely obtaining the orientation of slope discontinuities; 2) the possibility to monitor rock slopes which allows not only
, deformation tracking and change detection will significantly improve our understanding on how rock slopes behave and evolve. Perspectives include the use of new 3D sensing devices and the adaptation of techniques and methods recently developed in other
disciplines as robotics and 3D computer-vision to rock slope instabilities research.

Use of a three-dimensional laser scanner to digitally capture the topography of sand dunes in high spatial resolution

Use of a three-dimensional laser scanner to digitally capture the topography of sand dunes in high spatial resolution
The AA. report the results of a field study that was designed to test the feasibility of using ground-based LIDAR to map the topography of a sand dune in high spatial resolution. They present a surface topography model obtained from a scanning
experiment performed on a barchan dune in the White Sands National Monument, New Mexico in January 2003. The 3D surface model of the dune can describe the morphology with hitherto unprecedented detail.

Rapid production of virtual reality city models

In the approach presented in this paper, the geometric reconstruction of urban areas is based on height data from airborne laser scanning and 2D GIS, which provides the ground plan geometry of buildings. Both data sources are used to estimate
the type and parameter of basic primitives which in turn are combined to obtain complex building structures. The final output consists of 3D CAD models for the buildings. Using the reconstructed geometry, terrestrial images are mapped on to building façades

In situ characterization of grain-scale fluvial morphology using Terrestrial Laser Scanning

In situ characterization of grain-scale fluvial morphology using Terrestrial Laser Scanning
Digital elevation model ; England ; Grain size distribution ; Gravel ; Hertfordshire ; Methodology ; Micromorphology ; Scotland ; Sediment load ; Stream ; Terrestrial laser scanning ; United Kingdom
Terrestrial Laser Scanning (TLS) is a laser ranging technique, applying the same principles as airborne Lidar. It offers a new methodology for the rapid acquisition of high-resolution and high-precision surface elevation data from in situ sediments
. This paper presents the use of TLS as an alternative method for collecting high-resolution 3D data from fluvial gravel surfaces, enabling the development of grain-scale Digital Terrain Models (DTMs). Application to a coarse grained gravel system, the River

Innovative applications of laser scanning and rapid prototype printing to rock breakdown experiments

Innovative applications of laser scanning and rapid prototype printing to rock breakdown experiments
The AA. present the novel application of 2 technologies for use in rock breakdown experiments, i.e. close-range, ground-based 3D triangulation scanning and rapid prototype printing. These techniques aid analyses of form-process interactions across

A belvízelöntések térképezését megalapozó adatgyűjtés és a belvízképződés modellezése neurális hálózattal

3D scanner ; Absorption ; Channel ; Confluent ; Continental water ; Data collection ; Digital elevation model ; Drainage network ; Extreme event ; Geographical information system ; Great Hungarian Plain ; Hungary ; Hydrology ; Photointerpretation
; Réseau de drainage ; Scanner tridimensionnel ; Système d'information géographique
Inland excess water is a recurring problem on the Great Hungarian Plain. Large tracts of land are covered with water due to a lack of runoff and insufficient absorption capability of the soil or upwelling of groundwater. Laser altimeter scanning

Kaolinization of feldspar as displayed in scanning electron micrographs

Kaolinization of feldspar as displayed in scanning electron micrographs

Towards a protocol for laser scanning of rock surfaces

Towards a protocol for laser scanning of rock surfaces
Etude comparée ; Micromorphologie ; Météorisation ; Précision ; Scanner laser ; Technique de recherche ; Topographie
The precision of height measurements derived from laser scanning a weathered rock surface was analysed. Different registration methods for comparing surfaces to deduce weathering were assessed and the most precise was found to be the method
that used registration shapes as control, located in different planes relative to the scanned surface. In addition, the different sources of error in scanning precision were assessed by varying factors such as scan distance, lens configuration, scan angle
and the nature of the topography being scanned. From this analysis it was possible to suggest what the optimal scanning conditions were for this particular experimental set-up. The procedures outlined for assessing errors in the precision of height measurements
are transferable to other scanning studies.

A planning model for regional systems of CT scanners

A planning model for regional systems of CT scanners
Allemagne de l'Ouest ; Calcul économique ; Equipement ; Equipement hospitalier ; Géographie de l'Europe ; Implantation ; Modèle ; Radiologie ; Scanner CT
Modèle d'évaluation des implantations d'équipement hospitalier en scanners CT en Allemagne Fédérale. Coûts d'utilisation et coûts de transport.

Evaluation of remotely-sensed DEMs and modification based on plausibility rules and initial sediment budgets of an artificially-created catchment

laser scanning (TLS) data. Regions of differing morphological characteristics and vegetation cover were delineated. Three-dimensional (3D) models of volume change were established and mass change was derived from these models. DEMs were modified region

Analysis of planimetric accuracy of airborne laser scanning surveys

Analysis of planimetric accuracy of airborne laser scanning surveys
Cartographie automatique ; Modèle numérique de terrain ; Méthodologie ; Scanner à laser ; Télédétection
Avec l'augmentation de leur taux d'impulsion les scanners à laser aéroporté qui localisent les nuages deviennent une source de données intéressante pour la cartographie à partir de modèles numériques de terrain. L'A. présente ici une méthodologie

Segregated ice structures in various heaved permafrost landforms through CT scan

Segregated ice structures in various heaved permafrost landforms through CT scan
The study area is located near the Inuit community of Umiujaq and in the area around the mouth of the Nataspoka River on Hudson Bay. Images from tomodensitometric scanning (CT scan) on numerous permafrost cores from permafrost mounds and plateaus

Lithological discrimination in central Snowdonia using airborne multispectral scanner imagery

Lithological discrimination in central Snowdonia using airborne multispectral scanner imagery
Formation superficielle ; Géographie de l'Europe ; Géologie régionale ; Géomorphologie ; Royaume-Uni ; Scanner aéroporté ; Snowdown ; Télédétection ; Wales
Utilise un facteur d'indexation optimale (OIF) pour classer les combinaisons des 3 bandes de données collectées par scanner aéroporté, et une analyse en composante principale (ACP) pour compresser les données multibandes. Les fortes valeurs d'OIF et

Towards a protocol for laser scanning in fluvial geomorphology

Towards a protocol for laser scanning in fluvial geomorphology
This paper describes the field and processing techniques required for oblique laser scanning to acquire 0.01 m resolution digital elevation data of an upland reach of the River Wharfe in the UK. The study site is variable with rapidly changing
morphology, diverse vegetation and the presence of water, and these are evaluated with respect to laser data accuracy. Scan location, frequency and distance are discussed with reference to survey accuracy and efficiency, and a field protocol is proposed

Roughness determination of coarse grained alpine river bed surfaces using Terrestrial Laser Scanning data

Roughness determination of coarse grained alpine river bed surfaces using Terrestrial Laser Scanning data
Bavaria ; Germany ; Grain size distribution ; Mountain ; Research technique ; River bed ; Roughness ; Stream ; Terrestrial laser scanning
The goal of this research is to improve upon the methods for roughness length determination in gravel-bed rivers using terrestrial laser scanning (TLS). To this end, 2 principle methodological considerations were examined. 1.) The influence
of the number of scan positions on roughness calculation. 2.) The influence of grid-cell size on roughness calculation during post-processing. Scan data were furthermore compared to sediment samples to relate TLS-data to conventional roughness calculation
methods. Several test sites in the Reintal valley, Bavaria, Germany were scanned from multiple orientations. The results from these experiments show that despite minor particle shading, roughness length determination does not depend significantly
on the number of scan orientations used. However, results clearly show that roughness length determination depends highly on the choice of grid cell size during post processing. This study supports the use of TLS as the most appropriate and versatile method

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