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  • The production of digital elevation models for experimental model landscapes
  • Comparative study ; Digital elevation model ; Experimentation ; Geomorphology ; Model ; Photogrammetry ; Rainfall simulation ; Soil erosion ; Watershed
  • Bassin-versant ; Erosion des sols ; Etude comparée ; Expérimentation ; Géomorphologie ; Modèle ; Modèle numérique de terrain ; Photogrammétrie ; Simulation de pluie
  • Automated digital photogrammetry was used to produce digital elevation models of experimental model landscapes under controlled laboratory conditions as part of a series of rainfall erosion experiments looking at the evolution of landforms
  • in response to erosion. The method allowed the elevations of the experimental landscapes to be studied in great detail on a regular grid digital terrain map. Digital photogrammetry produced elevation data at a resolution of 6 mm with a standard deviation
  • Causes and consequences of error in digital elevation models
  • Bibliography ; Digital elevation model ; Error ; Methodology ; Model ; Physical geography ; Typology
  • Bibliographie ; Erreur ; Géographie physique ; Modèle ; Modèle numérique de terrain ; Méthodologie ; Typologie
  • This paper reviews research on the understanding, modelling and propagation of error in DEMs, with the aim of presenting a comprehensive statement of the issues surrounding these topics : sources of error in DEMs, error models, error propagation
  • Methods for the visualization of digital elevation models for landform mapping
  • Cartography ; Comparative study ; Digital elevation model ; Drumlin ; Geomorphological mapping ; Glacial features ; Ireland ; Lineament ; Photogrammetry
  • Cartographie ; Cartographie géomorphologique ; Drumlin ; Etude comparée ; Glaciaire ; Irlande ; Linéament ; Modèle numérique de terrain ; Photogrammétrie
  • Etude comparée de l'utilisation de modèles numériques de terrain pour la cartographie géomorphologique des phénomènes glaciaires en Irlande.
  • Main features of geomorphology of the Sudetes re-assessed in the light of digital elevation model
  • Czech Republic ; Digital elevation model ; Geomorphology ; Mountain ; Sudety ; Tectonics
  • Géomorphologie ; Modèle numérique de terrain ; Montagne ; Sudety ; Tchèque république ; Tectonique
  • The Sudetes as a geomorphological region are distinguished by complicated spatial pattern of high- and low-altitude terrains and variable mean slope gradients across the range. An analysis of a digital elevation model and maps derived from the model
  • Channel head location and characteristics using digital elevation models
  • Australia ; Digital elevation model ; Drainage network ; Hydrology ; Northern Territory ; Slope gradient ; Spatial distribution ; Watershed
  • Australie ; Bassin-versant ; Distribution spatiale ; Hydrologie ; Modèle numérique de terrain ; Northern Territory ; Pente de versant ; Réseau de drainage
  • extent channel head location can be predicted by the area-slope relationship and the cumulative area distribution. The effect of digital elevation model grid resolution on the ability to locate channel head position and assess hillslope length will also
  • Geomorphometric mapping of Asia Minor from GLOBE digital elevation model
  • Anatolia ; Asia ; Cartography ; Cluster analysis ; Digital elevation model ; Geomorphometry ; Mountain ; Peneplain ; South-Eastern Asia ; Turkey
  • Analyse des groupes ; Anatolie ; Asie ; Asie du Sud-Est ; Cartographie ; Géomorphométrie ; Modèle numérique de terrain ; Montagne ; Pénéplaine ; Turquie
  • This paper focuses on the mapping of landscapes in Asia Minor on the basis of the moderate resolution digital elevation model GLOBE that provides a regional relief representation. Finally, the classification identifies 2 branches. In between
  • The use of digital elevation models in geomorphology
  • Bassin-versant ; Belgique ; Erosion des sols ; Géomorphologie ; Hydrologie ; Modèle ; Modèle numérique ; Pente de versant ; Risque naturel ; Système d'information géographique
  • Belgium ; Geographical information system ; Geomorphology ; Hydrology ; Model ; Natural hazards ; Numerical model ; Slope gradient ; Soil erosion ; Watershed
  • representation of the real land surface. This can be achieved by the use of Digital Elevation models. The power of this tool is demonstrated by some examples in landform description, landform analysis and spatial modelling.
  • The interaction between Geographical Information Systems and geomorphology gains interest, not only because of the more quantitative approach. It is demonstrated in this paper that the main progress is due to the introduction of the digital
  • Investigation of elevation bias of the SRTM C- and X-band digital elevation models
  • Altitude ; Australia ; Digital elevation model ; Land utilisation ; Plant canopy ; Queensland ; Radar imagery ; Remote sensing ; Sar imagery ; Statistical bias ; Vegetation
  • Altitude ; Australie ; Biais statistique ; Couvert végétal ; Image radar ; Image sar ; Modèle numérique de terrain ; Occupation du sol ; Queensland ; Télédétection ; Végétation
  • This paper presents results of a comparative study of the vegetation-caused elevation bias of the space shuttle topographic mission data product, both C- and X-band (SRTM.C/X). The SRTM.C/X bands data were compared against a high-resolution digital
  • relating the elevation bias to the percentage of the vegetation cover of a given land parcel. This model, once verified on varieties of vegetation types, could be utilised to estimate and eliminate the elevation bias from the InSAR elevation model.
  • terrain model and discussed. As a test site, an area on the Gold Coast, Queensland, Australia, was selected. This area is covered by vegetation varying from grassland and shrubs to forest. The study method allowed the development of a statistical model
  • The digital elevation model of Italy for geomorphology and structural geology
  • Géomorphologie structurale ; Italie ; Modèle ; Modèle numérique ; Néotectonique ; Pente de versant ; Statistique ; Tectonique
  • Italy ; Model ; Neotectonics ; Numerical model ; Slope gradient ; Statistics ; Structural geomorphology ; Tectonics
  • Three different methods for calculating from a Digital Elevation Model (DEM) slope and aspect are discussed : the Four Contiguous Right Triangles, the Maximum Downward Gradient and the Bicubic Spline First Derivative; the resulting maps have been
  • compared with each other at regional scale and for a small area with a slope map obtained by using classical techniques. The main goal of the comparison has been the choice of the best technique for the computation of the digital slope map of Italy.
  • A comparison of SRTM and high-resolution digital elevation models and their use in catchment geomorphology and hydrology : Australian examples
  • Australia ; Digital elevation model ; Geomorphology ; Hydrology ; Model ; New South Wales ; Northern Territory ; Remote sensing ; Runoff ; Soil erosion ; Soil moisture ; Watershed
  • Australie ; Bassin-versant ; Ecoulement ; Erosion des sols ; Géomorphologie ; Humidité du sol ; Hydrologie ; Modèle ; Modèle numérique de terrain ; New South Wales ; Northern Territory ; Télédétection
  • The AA. examine the Shuttle Radar Topography Mission (STRM) data for 3 catchments in Australia over a range of climates, geology and resultant geomorphology. The SRTM data are compared with high resolution digital elevation models. The AA. use basic
  • hydrology and geomorphology, as in all cases SRTM-derived catchment area is incorrect and smaller digital elevation grid sizes are required for accurate catchment-wide assessment.
  • Automated identification of yatsu valleys based on a semantic modeling of landforms using digital elevation models
  • Algorithm ; Classification ; Digital elevation model ; Geomorphology ; Honshu ; Japan ; Modelling ; Slope gradient ; Topography ; Topology ; Valley
  • Algorithme ; Classification ; Géomorphologie ; Honshū ; Japon ; Modèle numérique de terrain ; Modélisation ; Pente de versant ; Topographie ; Topologie ; Vallée
  • The aim of this study is to develop algorithms for identifying Yatsu valleys by topological measurements based on the semantic modeling of landforms using a DEM. Yatsu valleys are valleys with flat floors dissecting into the uplands and hills
  • Digital elevation model perspective plot overlays
  • Cartographie automatique ; Diagramme ; Données statistiques ; Généralités sur la géographie ; Infographie ; Modèle ; Représentation graphique
  • Méthode de représentation de données thématiques en perspective avec représentation des parties cachées. Modèle d'élévation numérisé, contrôle du tracé en huit couleurs. Exemples sur l'utilisation du sol et de la température moyenne annuelle
  • A comparison of interpolation methods for producing digital elevation models at the field scale
  • Comparative study ; Digital elevation model ; Geographical information system ; Geostatistics ; Interpolation ; Methodology ; Slope gradient ; Topography ; Turkey
  • Etude comparée ; Géostatistiques ; Interpolation ; Modèle numérique de terrain ; Méthodologie ; Pente de versant ; Système d'information géographique ; Topographie ; Turquie
  • of interpolation methods and the nature of errors in digital elevation models obtained with indirect survey methods for small-scale areas. The purpose of this study was therefore to investigate the size and spatial patterning of errors in digital elevation models
  • obtained with direct survey methods for large-scale areas, comparing Inverse Distance Weighting, Radial Basis Functions and Kriging interpolation methods to generate digital elevation models. This study is important because it shows how the accuracy
  • of the digital elevation model is related to data density and the interpolation algorithm used. Cross validation, split sample and jack-knifing validation methods were used to evaluate the errors. Global and local spatial auto-correlation indices were then used
  • In this study, the magnitudes and spatial patterning of elevation errors were examined, using the effects of interpolation methods. Measurements were performed with theodolite and levelling. Previous research has demonstrated the effects
  • to examine the error clustering. Finally, slope and curvature parameters of the area were modelled depending on the error residuals using ordinary least regression analyses. In this case, the best results were obtained using the thin plate spline algorithm.
  • Digital elevation modelling in a study of the neotectonic geomorphology of the Sierra Nevada, southern Spain
  • Espagne ; Faille ; Géomorphologie structurale ; Modèle numérique ; Montagne ; Méthodologie ; Néotectonique ; Sierra Nevada ; Statistique
  • Fault ; Methodology ; Mountain ; Neotectonics ; Numerical model ; Sierra Nevada ; Spain ; Statistics ; Structural geomorphology
  • Uplift and erosion creates truncated spurs on fault-controlled mountain slopes. The stepped morphology of these spurs reflects the uplift history of the Sierra Nevada since late Serravallian times. Digital Elevation Models (DEMs) offer a method
  • Field mapping and digital elevation modelling of submerged and unsubmerged hydraulic jump regions in a bedrock step-pool channel
  • California ; Cartography ; Digital elevation model ; Longitudinal section ; River bed ; Sierra Nevada ; Stream ; Stream flow ; Topography ; United States of America
  • California ; Cartographie ; Cours d'eau ; Ecoulement fluvial ; Etats-Unis ; Lit fluvial ; Modèle numérique de terrain ; Profil longitudinal ; Saut hydraulique ; Sierra Nevada ; Topographie
  • to reducing uncertainty associated with qualitative observations, the data provide the basis for quantitative comparison of different natural jets and jumps with engineered jets and jumps. The digital elevation models highlight the importance of recognizing
  • The aim was to develop a systematic methodology to rapidly survey, digitize and visualize bed and water surface topographies of 2 common types of natural jump regions (submerged and unsubmerged) in a bedrock step-pool channel. In addition
  • A morphological assessment of soil microtopography using a digital elevation model on one square metre plots
  • Bretagne ; Eau du sol ; France ; Géographie physique ; Géomorphométrie ; Microrelief ; Microtopographie ; Modèle numérique ; Porosité ; Propriété du sol ; Ruissellement ; Sol
  • Depression storage restrains overland flow and erosion. A technique for delimiting areas of depression storage from Digital Elevation Models (D. E. M. s) is described. The method is illustrated with an example from a field near Rennes (France
  • Automated recognition of valley heads from digital elevation models
  • Cartographie automatique ; Cartographie géomorphologique ; Fluviatile ; Grèce ; Généralités sur la géographie ; Modèle numérique ; Peloponnisos ; Tête de vallée ; Vallée
  • An automated technique for recognizing valley heads from digital elevation models is presented. The technique has been developed for valley head recognition because valley heads are known locations of geomorphological activity and because areal
  • Supervised classification of types of glaciated landscapes using digital elevation data
  • Cartographie automatique ; Classification ; Esker ; Etats-Unis ; Fluvioglaciaire ; Glaciaire ; Géomorphométrie ; Kame ; Michigan ; Modèle ; Modèle numérique ; Moraine
  • Automated mapping ; Classification ; Esker ; Fluvioglacial features ; Geomorphometry ; Glacial features ; Kame ; Michigan ; Model ; Moraine ; Numerical model ; United States of America
  • ) derived from digital elevation models (DEMs) to differentiate glaciated landscapes using maximum likelihood classification and artificial neural networks (ANN). The automated methods were trained and validated using an existing Quaternary geology map
  • Automated approaches for identifying different types of glaciated landscapes using digitally processed elevation data were evaluated. The AA. tested the ability of geomorphic measures (elevation, relative relief, roughness, and slope gradient
  • Deriving river networks and catchments at the European scale from medium resolution digital elevation data
  • Digital elevation model ; Drainage density ; Drainage network ; Europe ; Methodology ; Threshold ; Watershed
  • Bassin-versant ; Densité de drainage ; Europe ; Modèle numérique de terrain ; Méthodologie ; Réseau de drainage ; Seuil
  • The AA. present an application that delineates river networks and catchment boundaries across the European continent from a medium resolution (250 m) digital elevation model (DEM). They exploit novel algorithms based on the concepts of mathematical
  • morphology and implement a landscape stratification drainage density. The result has been validated by comparing the derived data to digital river and catchment data from other sources and with varying scales of observation.
  • Air temperature ; Climatic warming ; Colorado ; Digital elevation model ; Geographical information system ; Glacier dynamics ; Mountain ; Photogrammetry ; Rock glacier ; United States of America
  • Colorado ; Dynamique glaciaire ; Etats-Unis ; Glacier rocheux ; Modèle numérique de terrain ; Montagne ; Photogrammétrie ; Réchauffement climatique ; Système d'information géographique ; Température de l'air
  • Horizontal rock glacier displacements were measured by tracking large surficial rocks on temporal orthophotos from 1978, 1990, and 1999. Vertical change was measured by creating digital elevation models (DEMs) from digital stereopairs
  • , then substracting elevations to detect change. Because horizontal and vertical change is minimal, Front Range rock glaciers appear to be adjusted with current climate.