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  • Assessing a numerical cellular braided-stream model with a physical model
  • Braided channel ; Channel geometry ; Concept ; Fluvial dynamics ; Model ; Numerical model ; Stream
  • Chenal anastomosé ; Concept ; Cours d'eau ; Dynamique fluviale ; Géométrie hydraulique ; Modèle ; Modèle numérique
  • The AA. test the representation of braided channel morphodynamics in the Murray-Paola model, MP model, against the known characteristics (mainly from a sequence of high resolution digital elevation models) of a physical model of a braided stream
  • . It achieves this by initiating the model from real braided topography rather than white noise. This extension of the application of the MP model is used to identify characteristics that are not reproduced, to investigate their causes, propose modifications
  • and discuss both the implications for the formation of braiding and alternative modelling strategies.
  • 2005
  • Unconditional maximum likelihood estimation of linear and log-linear dynamic models for spatial panels
  • Dynamic model ; Error ; Matrix analysis ; Space time ; Spatial analysis ; United States of America
  • Analyse spatiale ; Calcul matriciel ; Erreur ; Espace-temps ; Etats-Unis ; Modèle dynamique
  • L'A. estime un modèle dynamique à effets fixes sur données de panel, dont l'extension permet d'inclure soit l'autocorrélation spatiale de l'erreur, soit une variable dépendante avec un décalage spatial. Les effets fixes sont éliminés, et une
  • 2005
  • Ecoulement ; Géomorphologie ; Hongrie ; Infiltration ; Modèle ; Modèle mathématique ; Terre arable
  • Arable land ; Geomorphology ; Hungary ; Infiltration ; Mathematical model ; Model ; Runoff
  • There are dozens of infiltration and erosion models that attempt to describe more and more exactly these processes. The aim of this paper is to introduce a dynamic mathematical model which is able to model the effect of a rainfall event on a plot
  • to the infiltration and to the runoff. The model consists of two sub-models. Firstly, the interception model determines the net rainfall which reaches the surface directly or through the vegetation. Secondly, the runoff model can show the spatial and temporal
  • 2005
  • Conceptual model of sediment processes in the upper Yuba River watershed, Sierra Nevada, CA
  • California ; Conceptual model ; Erosion rate ; Geographical information system ; Mass movement ; Slope dynamics ; United States of America ; Watershed
  • Bassin-versant ; California ; Dynamique de versant ; Etats-Unis ; Modèle conceptuel ; Mouvement de masse ; Système d'information géographique ; Vitesse d'érosion
  • The conceptual model illustrates key processes controlling sediment dynamics in the upper Yuba River watershed and was tested and revised using field measurements, aerial photography, and low elevation videography. Finally, the AA. propose
  • that spatially distributing the components of a conceptual model in a GIS framework provides a guide for developing more detailed sediment budgets or numerical models making it an inexpensive way to develop a roadmap for understanding sediment dynamics
  • 2005
  • The dynamic coupling model and its application of urbanization and eco-environment in Hexi Corridor
  • Arid area ; China ; Ecodevelopment ; Gansu ; Landscape dynamics ; Model ; Urbanization
  • Années 1985-2003 ; Chine ; Domaine aride ; Dynamique du paysage ; Eco-développement ; Gansu ; Modèle ; Urbanisation
  • This paper, taking Hexi Corridor as an example, analyzes the alternating intimidation and the dynamic evolving relation between urbanization and eco-environment in arid area of West China. The AA. argue that the harmonious development system
  • 2005
  • Modelling the effect of waves, weathering and beach development on shore platform development
  • Cliff ; Coastal dynamics ; Coastal environment ; Erosion ; Mathematical model ; Model ; Shore platform ; Tide ; Wave
  • Dynamique littorale ; Erosion ; Falaise ; Littoral ; Marée ; Modèle ; Modèle mathématique ; Plate-forme littorale ; Vague
  • A mathematical model was used to study shore platform development. In addition to mechanical wave erosion, this model considers the effect of a number of other important factors, including platform downwearing by weathering, the abrasive
  • 2005
  • Identification of climate controls on the dynamic behaviour of the Subarctic glacier Salajekna, northern Scandinavia
  • Climate ; Climatic trend ; Europe ; Glacier ; Glacier dynamics ; Glacier mass balance ; Model ; Nineteenth Century ; Northern Europe ; Photogrammetry ; Remote sensing ; Scandinavia ; Subarctic zone ; Twentieth Century
  • Bilan de masse ; Climat ; Dynamique glaciaire ; Europe ; Europe du Nord ; Glacier ; Modèle ; Photogrammétrie ; Scandinavie ; Siècle 19 ; Siècle 20 ; Tendance du climat ; Télédétection ; Zone subarctique
  • The AA. describe the dynamic behaviour of Salajekna, a valley glacier, over the last 200 years using terrestrial observations, in situ measurements, remote sensing observations and glacier reconstructions. The response time of the glacier
  • was calculated using analytical models and field measurements.
  • 2005
  • Dynamic modelling for linear erosion initiation and development under climate and land-use changes in northern Laos
  • Bassin-versant ; Changement climatique ; Changement global ; Ecoulement ; Erosion des sols ; Erosion hydrique ; Laos ; Modèle ; Utilisation du sol ; Zone intertropicale
  • Climatic change ; Global change ; Land use ; Laos ; Model ; Runoff ; Soil erosion ; Tropical zone ; Water erosion ; Watershed
  • This study investigates to what extent GIS-based modelling using topographic as well as soil and land-use information may be a useful tool for predicting linear erosion initiation and development in agricultural landscapes. The AA. hypothesize
  • that soil incision can be modelled in a physically deterministic way by using a threshold value of estimated flow velocity. Their second objective is to evaluate the impact of land-use and climatic changes upon linear erosion. Field observations of linear
  • erosion in a watershed of Laos under sloping land conditions were compared to estimated flow velocities estimated using a process-based model.
  • 2005
  • A map overlay error model based on boundary geometry
  • Error ; Geographical information system ; Landscape dynamics ; Model ; Simulation
  • Dynamique du paysage ; Erreur ; Modèle ; Simulation ; Système d'information géographique
  • Une simulation numérique des déplacements des limites polygonales sert à propager des erreurs de coordonnées en direction des recouvrements spatiaux. Le modèle se distingue de modèles d'erreur plus anciens dans la mesure où il incorpore la
  • 2005
  • Understanding the temporal dynamics of the wandering Renous River, New Brunswick, Canada
  • Aerial photography ; Braided channel ; Canada ; Channel geometry ; Fluvial dynamics ; New Brunswick ; Photointerpretation ; Stream ; Twentieth Century
  • This research investigates the long-term (54-year) average state of a wandering river and then explores the detailed channel changes. The study has 2 objectives : (1) to examine the temporal dynamics of a wandering river using a conceptual model
  • and (2) to investigate and test the conceptual model using historical analysis of channel locations and geometry, and field-based channel characteristics of case studies. The wandering Renous River was mapped from aerial photographs (1945, 1965, 1983
  • 2005
  • Dynamics of glacial and periglacial processes as evidence of global change
  • Action glaciaire ; Changement global ; Cycle gel-dégel ; Glaciaire ; Modelé glaciaire ; Périglaciaire ; Quaternaire
  • Glacial and periglacial processes, their landforms, influences of cryogenic destruction, and repeated freezing and thawing effects in rocks and their weathered mantle are described. Main features and dynamics of present-day and former glacial
  • 2005
  • Modelling water erosion in the Sahel : application of a physically based soil erosion model in a gentle sloping environment
  • Burkina ; Distribution spatiale ; Domaine aride ; Ecoulement ; Erosion des sols ; Erosion hydrique ; Infiltration ; Modèle ; Sahel ; Transport sédimentaire
  • Arid area ; Burkina ; Infiltration ; Model ; Runoff ; Sahel ; Sediment transport ; Soil erosion ; Spatial distribution ; Water erosion
  • in northern Burkina Faso. It is concluded that the modified version of European Soil Erosion Model, EUROSEM, in PCRaster for the Sahel is a fully dynamic erosion model, able to simulate infiltration, runoff routing, pool formation, sediment transport
  • This study aims to develop a physically based model that incorporates all water erosion controlling processes in a Sahelian environment. The model is calibrated and tested with field data from the 2001 rainy season in the Katacheri catchment
  • 2005
  • Postglacial topographic evolution of glaciated valleys : a stochastic landscape evolution model
  • British Columbia ; Canada ; Climatic change ; Cold area ; Glacial valley ; Glacier retreat ; Landscape dynamics ; Model ; Stochastic model
  • British Columbia ; Canada ; Changement climatique ; Dynamique du paysage ; Modèle ; Modèle stochastique ; Paraglaciaire ; Recul du glacier ; Vallée glaciaire ; Zone froide
  • The AA. have studied the evolution of an idealized glaciated valley during the period following retreat of ice using a numerical model. The model incorporates a stochastic process to represent deep-seated landsliding, non-linear diffusion
  • to represent shallow landsliding and an approximation of the Bagnold relation to represent fluvial sediment transport. It was calibrated using field data from several recent surveys within British Columbia, Canada. This model predicts a rapid rate of fluvial
  • sediment transport following deglaciation with a subsequent gradual decline, similar to that inferred for Holocene time. The AA. also describe how changes in the model parameters affect the estimated magnitude and duration of the paraglacial sediment pulse.
  • 2005
  • Deglaciation dynamics following the Little Ice Age on Svalbard : implications for shaping of landscapes at high latitudes
  • Arctique ; Calotte glaciaire ; Déglaciation ; Eau de fonte ; Glacier ; Modelé glaciaire ; Moraine ; Petit âge glaciaire ; Svalbard
  • Situation géologique et climatique. Le Plata˙breen et son assemblage de modelés glaciaires marginaux. La dégradation du glacier et les moraines de carottes de glace. La chronologie relative et l'évolution des zones morphogénétiques du Plataberget
  • 2005
  • Modelling catchment-scale erosion patterns in the East African Highlands
  • Soil erosion patterns : evolution, spatio-temporal dynamics and connectivity. Special issue
  • Afrique ; Afrique de l'Est ; Bassin-versant ; Distribution spatiale ; Erosion des sols ; Hydrologie ; Infiltration ; Kenya ; Modèle ; Montagne ; Ruissellement ; Tanzanie ; Vitesse d'érosion
  • Africa ; Eastern Africa ; Erosion rate ; Hydrology ; Infiltration ; Kenya ; Model ; Mountain ; Rill wash ; Soil erosion ; Spatial distribution ; Tanzania ; Watershed
  • This study aimed to evaluate the performance of a simple empirical model (Morgan, Morgan and Finney model, MMF) in predicting spatial patterns of erosion at 2 small catchments in the East African Highlands : Kwalei (Tanzania) and Gikuuri (Kenya
  • ). Erosion maps predicted by the MMF model were compared with erosion maps obtained by direct survey. The spatial pattern of erosion predicted by the MMF model was driven by the accumulation of surface runoff, which did not consider the possibility of re
  • -infiltration along the slope. The model predictions could be improved by introducing a more realistic hydrological component for the prediction of surface runoff along the hillslope.
  • 2005
  • Modèle amélioré d'évaluation de la périodicité des changements de niveau et des éléments du bilan hydrique de la mer Caspienne
  • Usoveršenstvovannaâ model' ocenki periodičnosti izmenenij urovnâ i èlementov vodnogo balansa Kaspijskogo morâ
  • Caspienne Sea ; European part of Russia ; Evaporation ; Mathematical model ; Model ; Runoff ; Sea level ; Spatial variation ; System dynamics ; Water budget
  • Bilan hydrique ; Caspienne ; Dynamique de système ; Ecoulement ; Evaporation ; Modèle ; Modèle mathématique ; Niveau marin ; Russie d'Europe ; Variation spatiale
  • Mise au point d'un modèle mathématique de la dynamique de la surface et du niveau de la Caspienne, de l'évaporation et du reflux des eaux dans le golfe de Kara-Bogaz-Gol lors de fluctuations d'écoulement des eaux.
  • 2005
  • Modelling scenarios of land use change in northern China in the next 50 years
  • Années 1990 ; Années 2000-2050 ; Chine ; Chine du Nord ; Ecologie ; Impact ; Modèle ; Scénario ; Simulation ; Utilisation du sol
  • China ; Ecology ; Impact ; Land use ; Model ; Northern China ; Scenario ; Simulation ; Years 1990-99
  • A system dynamics (SD) model with the aim to modelling scenarios of land use change and assessing ecological impact in northern China in the next 50 years is developed here. The accuracy assessment with the historic data from 1990 to 2001 indicated
  • the SD model is robust. The aim of this work is to provide a foundation for the understanding of the responses of regional land use to ecological security and future development of tempo-spatial land use models satisfying ecological security requirements.
  • 2005
  • Cluster dynamics : new evidence and projections for computing services in Great Britain
  • Agglomération ; Compétitivité ; Croissance économique ; Distribution spatiale ; Emploi ; Entreprise ; Externalités ; Great Britain ; Modèle ; Royaume-Uni ; Service
  • Agglomeration ; Competitiveness ; Economic growth ; Employment ; Enterprise ; Externalities ; Great Britain ; Model ; Service ; Spatial distribution ; United Kingdom
  • Les AA. testent les principales hypothèses relatives à l'importance des groupes horizontaux pour la croissance de l'emploi dans les petites entreprises de services informatiques en Grande-Bretagne. Ils estiment des modèles économétriques spatiaux
  • , compte tenu des conditions prévalant côté offre et côté demande, afin d'isoler l'effet de l'intensité initiale du groupe. Le développement ultérieur du groupe est projeté selon le modèle, ce qui met en relief son émergence et son intensification
  • 2005
  • DEM resolution effects on shallow landslide hazard and soil redistribution modelling
  • Digital elevation model ; Landslide ; Modelling ; New Zealand ; North Island ; Precipitation ; Risk ; Sediment budget ; Slope dynamics ; Slope gradient ; Watershed
  • Bassin-versant ; Bilan sédimentaire ; Dynamique de versant ; Glissement de terrain ; Modèle numérique de terrain ; Modélisation ; North Island ; Nouvelle-Zélande ; Pente de versant ; Précipitation ; Risque
  • The AA. analyse the effects of digital elevation model (DEM) resolution on the results of a model that simulates spatially explicit relative shallow landslide hazard and soil redistribution patterns and quantities. They analyse distributions
  • 2005
  • Modelling granular sediment transport over water-worked gravels
  • Capacité de charge ; Charge solide ; Cours d'eau ; Ecoulement ; Géométrie hydraulique ; Modèle ; Modèle numérique ; Photogrammétrie ; Transport sédimentaire
  • Carrying capacity ; Channel geometry ; Model ; Numerical model ; Photogrammetry ; Runoff ; Sediment load ; Sediment transport ; Stream
  • This paper reports a numerical model that calculates the transport paths of individual granular particles over a natural water-worked gravel surface. Surface topography is measured using digital photogrammetry and incorporated into a computational
  • fluid dynamics (CFD) scheme by the application of a porosity algorithm. The predicted hydraulics determine the forces acting on each particle enabling the particle trajectory to be solved by Langrangian transport equations. The methodology demonstrates
  • 2005