Airborne Laser scanning : an operational remote sensing technique for digital elevation mapping in coastal areas
Altitud ; Cartografía ; Detección a distancia ; Duna costera ; Europa ; Europa del Oeste ; Gestión ; Holanda ; Laser ; Mar del Norte ; Medio litoral ; Morfodinámica ; Método aerotransportado ; Métodoscanner ; Océano Atlántico ; Océano Atlántico
; geographic information systems ; landform evolution ; laser methods ; management ; remote sensing ; scanner methods
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
Atlantic Ocean ; Bay of Biscay ; Europe ; France ; North Atlantic ; Northeast Atlantic ; Western Europe ; acoustical methods ; high resolution ; inner shelf ; landform evolution ; marine transport ; modern ; seismic methods ; side-scanning methods
Actual ; Alta resolucion ; Duna submarina ; Europa ; Europa del Oeste ; Francia ; Golfo de Vizcaya ; Morfodinámica ; Método acústico ; Método sísmico ; Océano Atlántico ; Océano Atlántico Norte ; Plataforma continental interna ; Tempestad
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
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
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
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
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
Roof type determination from a sparse laser scanning point cloud
Brno ; Bâtiment ; Mesure laser ; Modèle ; Modèle numérique de terrain ; Pardubice ; Scanner tridimensionnel ; Sobotka ; Tchèque république ; Toit ; Ville
3D scanner ; Brno ; Building ; Czech Republic ; Digital elevation model ; Model ; Roof ; Town ; laser measures
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
Application and comparison of the results of optical and scanning electron microscopic methods for grain-shape examination on Quaternary formations
The purpose of this study was to determine the facies of sand sediment from Quaternary geological profiles in the Nyírség area in North Hungary, and compare the results of the traditional grain-shape examination procedures with those of the scanning
Application of a laser scanner to quantify properties of soil crusts
This paper presents applications of a laser scanner to quantify topography changes after a sequence of rain events and to measure near-surface bulk density from plot-boxes in the laboratory and in situ field plots. The objective is to use both
Numérisation des documents cartographiques à l'aide d'un scanner d'édition
publishing scanner and processing of such images by raster painting programmes. One of the most effective usages of such scanner in geographical practical work is the digitizing of contour maps for further thematic maps composition and design. - (L'A.).
Atlas zur Interpretation von kosmichen Scanneraufnahmen. Multispektralsystem Fragment . Methodik und Ergebnisse. Atlas for the interpretation of scanner space imagines. Multispectral system Fragment . Methodolgy and results
for every map is given a comparison of scanner space images with traditional geographical map. - (IH)
Defining shore platform boundaries using airborne laser scan data : a preliminary investigation
As an initial evaluation of the potential of digital elevation models (DEMs) and geographic information systems (GISs) for geomorphic characterization of rocky shorelines, airborne laser scan (ALS) data have been used to characterize shore platforms
Quantifying interpolation errors in urban airborne laser scanning models
La méthode est susceptible d'applications multiples dans la modélisation des surfaces urbaines. Identification et analyse de l'amplitude de la structure spatiale des résidus provenant des modèles airborne laser scanning, à des échelles multiples. Il
Confocal scanning light microscopy is a valuable new method for examining the nature and progress of stone weathering at a level of resolution between optical microscopy and scanning electron microscopy. Not only is it non-destructive, but it can