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  • Critical perspectives on the evaluation and optimization of complex numerical models of estuary hydrodynamics and sediment dynamics
  • Charge en suspension ; England ; Estuaire ; Hydrodynamique ; Modèle ; Modèle numérique ; Royaume-Uni ; Statistique ; Suffolk ; Série chronologique ; Transport sédimentaire
  • England ; Estuary ; Hydrodynamics ; Model ; Numerical model ; Sediment transport ; Statistics ; Suffolk ; Suspended load ; Time series ; United Kingdom
  • This paper examines the basis for evaluating the performance of complex hydrodynamic and sediment transport models, and the quantitative and qualitative understanding that can emerge from this kind of modelling, especially in situations where data
  • limitations restrict the ability to parameterize processes that are known to be important. First, some general arguments relating to model validation are presented. Second, some new approaches to model performance evaluation and optimization are suggested
  • with reference to illustrative hydrodynamic and sediment transport model results for a muddy meso-tidal estuary.
  • 2010
  • Long-term river meandering as a part of chaotic dynamics ? A contribution from mathematical modelling
  • Auto-organisation ; Chaos ; Cours d'eau ; Géométrie hydraulique ; Modèle ; Modèle mathématique ; Méandre ; Série chronologique
  • Channel geometry ; Chaos ; Mathematical model ; Meander ; Model ; Self-organizing behaviour ; Stream ; Time series
  • The AA. study the possible signatures of a chaotic behaviour or a self-organized criticality state triggered in river meandering dynamics by repeated occurrence of cutoff processes. The analysis is carried out examining, through some robust
  • obtained by using a suitable physics-based simulation model for river meandering. The results are consistent and show that, at least from a modelling point of view, no evidence of chaotic determinism or self-organized criticality is detectable
  • in the investigated meandering dynamic.
  • 2010
  • Simulation on the dynamics of forest area changes in Northeast China
  • China ; Econometric model ; Forest ; Forestry ; Land use ; North-Eastern China ; Production ; Resource management ; Simulation ; Vegetation dynamics
  • Chine ; Chine du Nord-Est ; Dynamique de la végétation ; Forêt ; Gestion des ressources ; Modèle économétrique ; Production ; Simulation ; Sylviculture ; Utilisation du sol
  • To explore the dynamics of forest area change in Northeast China, an econometric model is developed which is composed of three equations identifying forestry production, conversion from open forest to closed forest and conversion from other land
  • uses to closed forest so as to explore the impacts on the forest area changes from demographic, social, economic, location and geophysical factors. On this basis, the AA. employ the Dynamics ofLand System (DLS) model to simulate land-use conversions
  • 2010
  • Growth and convergence in a multiregional model with space-time dynamics
  • Bien-être ; Croissance économique ; Economie régionale ; Econométrie ; Espace-temps ; Europe ; Modèle néoclassique ; Niveau de vie ; Proximité ; Union européenne
  • Econometry ; Economic growth ; Europe ; European Union ; Living standard ; Neo-classical model ; Proximity ; Regional economy ; Space time ; Well-being
  • Il s'agit de tester quatre hypothèses distinctes pour savoir dans quelle mesure la localisation relative d'une économie affecte la croissance et le bien-être économiques, en utilisant l'extension d'un modèle de croissance néoclassique selon Solow
  • 2010
  • Evaluating the significance of event and post-event sediment dynamics in a first order tributary using multiple sediment budgets
  • Climatic change ; Erosion ; Gully erosion ; Impact ; Mass movement ; Model ; Northern England ; Sediment budget ; Sediment transport ; Slope dynamics ; United Kingdom ; Watershed
  • Années 2002-2008 ; Bassin-versant ; Bilan sédimentaire ; Changement climatique ; Dynamique de versant ; Erosion ; Impact ; Modèle ; Mouvement de masse ; Northern England ; Ravinement ; Royaume-Uni ; Transport sédimentaire
  • dynamics in the period 2002-2008. A multiple sediment budget approach, was used to construct 3 sediments budgets (2002, 2003-2004, 2008). Results clearly demonstrate changes in the dominance of slope erosion versus channel erosion/transfer. Discussion about
  • the limits of this approach and the accuracy of the sediment budget models that are developed. The AA. aim also to assess the relationship between contemporary meteorological (climate) conditions and sediment system response.
  • 2010
  • Dynamic interactions of life and its landscape : feedbacks at the interface of geomorphology and ecology
  • Adaptation ; Biodiversity ; Co-evolution ; Ecology ; Environmental management ; Geomorphology ; Human impact ; Impact ; Inter-disciplinary approach ; Landscape dynamics ; Model ; Population dynamics ; Research ; Sustainable development
  • Action anthropique ; Adaptation ; Biodiversité ; Co-évolution ; Dynamique des populations ; Dynamique du paysage ; Développement durable ; Ecologie ; Gestion de l'environnement ; Géomorphologie ; Impact ; Interdisciplinarité ; Modèle ; Recherche
  • and indirect actions). Also outlined are the state of the art in analytical, experimental and modelling techniques in ecological and geomorphological research, and novel new research avenues that combine these techniques are suggested.
  • 2010
  • Simulating pedestrian movement in dynamic environments
  • Computing ; Flow ; Pedestrians ; Simulation ; Spatial interaction ; System dynamics
  • approche, à partir de la simulation des flux de piétons dans des espaces confinés. Le modèle MAGE développé permet notamment d’explorer le rôle joué par les interactions locales sur la dynamique globale du système modélisé.
  • 2010
  • Étude du climat ouest-africain à l'aide du Modèle Atmosphérique Régional M.A.R.
  • Africa ; Atmospheric circulation ; Atmospheric dynamics ; Climate ; Model ; Modelling ; Precipitation ; West Africa
  • Afrique ; Afrique de l'Ouest ; Circulation atmosphérique ; Climat ; Dynamique de l'atmosphère ; Modèle ; Modélisation ; Précipitation
  • 2010
  • Modeling of a debris flow from the Hrenovec torrential watershed above the village of Kropa
  • Debris flow ; Landslide ; Model ; Precipitation ; Slope dynamics ; Slope gradient ; Slovenia ; Watershed
  • Bassin-versant ; Coulée de débris ; Dynamique de versant ; Glissement de terrain ; Modèle ; Pente de versant ; Précipitation ; Slovénie
  • In this paper, debris-flow modeling is shown specifically on the basis of a potential debris flow from the Hrenovec torrential watershed above the village of Kropa in NW Slovenia. This site was chosen, because in this particular torrential watershed
  • 2010
  • Simulating urban networks through multiscalar space-time dynamics : Europe and the United States, 17th-20th centuries
  • Business cycle ; Europe ; Model ; Multi-agent model ; Settlement system ; Simulation ; Space time ; United States of America ; Urban dynamics ; Urban function ; Urban network ; Urban system
  • Cycle économique ; Dynamique urbaine ; Espace-temps ; Etats-Unis ; Europe ; Fonction urbaine ; Modèle ; Modèle multi-agents ; Réseau urbain ; Simulation ; Système de peuplement ; Système urbain
  • Présentation d'un modèle multi-agents servant à simuler les systèmes de villes. Selon une théorie de l'évolution basée sur l'observation de réseaux de villes à travers le monde et sur de longues périodes de temps, on peut identifier ce qui les
  • l'expansion dans l'espace selon la diffusion des innovations. On peut déceler certains contrastes dans les tailles de villes et des différenciations dans les fonctions économiques urbaines. Le modèle offre la possibilité d'intégrer une nouvelle fonction
  • 2010
  • Measuring and modelling the actual energy involved in aggregate breakdown
  • Agrégat ; Australie ; Erodabilité ; Erosion des sols ; Géophysique ; Modèle ; New South Wales ; Propriétés du sol ; Sol
  • Aggregate ; Australia ; Erodibility ; Geophysics ; Model ; New South Wales ; Soil ; Soil erosion ; Soil properties
  • and, the dynamics of particle-size redistribution can be described as a function of dispersive energy. To achieve this, soil samples representing Vertisols and Ferrasols are assessed by simultaneously modelling the dynamics of aggregate breakdown in a range of soil
  • 2010
  • Modelling urban expansion using a multi agent-based model in the city of Changsha
  • Années 2006-2015 ; Changsha ; Chine ; Croissance urbaine ; Hunan ; Modèle ; Processus de décision ; Système multi-agents ; Urbanisation
  • China ; Decision process ; Hunan ; Model ; Multi-agent system ; Urban growth ; Urbanization
  • The AA. have built up a set of spatial-temporal land resource allocation rules and developed a dynamic urban expansion model based on a multi-agent system, which can simulate the interaction among different agents, such as residents, peasants
  • , and governments. This model is applied to simulate urban expansion process taking Changsha City as a study area. The results show that this model can not only reflect basic characteristics of urban expansion, but also help explain the reasons for urban expansion
  • 2010
  • Modeling landscape evolution
  • Colorado ; Digital elevation model ; Drainage network ; Earth surface processes ; Erosion ; Model ; Runoff ; Sediment transport ; Slope dynamics ; United States of America ; Watershed
  • Bassin-versant ; Colorado ; Dynamique de versant ; Ecoulement ; Erosion ; Etats-Unis ; Géomorphodynamique ; Modèle ; Modèle numérique de terrain ; Réseau de drainage ; Transport sédimentaire
  • and quantitative modelling of geology, vegetation and erosion processes, will provide insights into the mechanisms that control catchment form and function. This paper reviews landscape theory - in the form of numerical models of drainage basin evolution
  • 2010
  • Numerical modelling of climate change impacts on Saint-Lawrence River tributaries
  • Années 2010-2099 ; Canada ; Changement climatique ; Changement global ; Cours d'eau ; Dynamique fluviale ; Effet de serre ; Impact ; Modèle ; Niveau de base ; Québec ; Saint-Laurent ; Transport sédimentaire
  • Base level ; Canada ; Climatic change ; Fluvial dynamics ; Global change ; Greenhouse effect ; Impact ; Model ; Quebec ; Saint-Laurent ; Sediment transport ; Stream
  • The impacts of climate-induced changes in discharge and base level in 3 tributaries of the Saint-Lawrence River, Québec, are modelled for the period 2010–2099 using a one-dimensional morphodynamic model. Changes in channel stability and bed-material
  • delivery to the Saint-Lawrence River over this period are simulated for all combinations of 7 tributary hydrological regimes (present-day and those predicted using 3 global climate models and 2 greenhouse gas emission scenarios) and 3 scenarios of how
  • the base level provided by the Saint-Lawrence River will alter (no change, gradual fall, step fall). The different results highlight the importance of investigating several rivers using several climate models in order to determine trends in climate change
  • 2010
  • The evolution of firm growth dynamics in the US pharmaceutical industry
  • Les AA. étudient la dynamique de croissance de l’industrie pharmaceutique entre 1950 et 2003 aux Etats-Unis. Ils analysent les changements importants intervenus au niveau de la taille et des modèles de croissance de ces entreprises. Les résultats
  • 2010
  • A continuous model for sand dunes : review, new developments and application to barchan dunes and barchan dune fields
  • Barkhane ; Dune ; Eolien ; Géomorphogenèse ; Modèle ; Transport sédimentaire ; Vitesse du vent
  • Aeolian features ; Barchan ; Dune ; Geomorphogenesis ; Model ; Sediment transport ; Wind speed
  • validated and able to simulate realistic barchan dunes, which are the basic solution of the model in the condition of unidirectional flow and scarce sediments. From the simulation, the AA. extract new relations describing the morphology and dynamics
  • The AA. present an updated review of such a model for aeolian dunes, including important modifications to improve its predicting power. For instance, they add a more realistic wind model and provide a self-consistent set of parameters independently
  • 2010
  • Cold area ; Model ; Mountain ; Periglacial features ; Regression analysis ; Slope dynamics ; Solifluction ; Spatial analysis ; Sweden
  • Abisko ; Analyse de régression ; Analyse spatiale ; Dynamique de versant ; Modèle ; Montagne ; Périglaciaire ; Solifluxion ; Suède ; Zone froide
  • The occurrence of turf-banked solifluction landforms in the Abisko region was analysed using a grid-based approach and statistical modelling through logistic regression. Significant parameters in the model were the vegetation index NDVI, annual
  • incoming potential radiation, wetness index, slope gradient and elevation. The model had an acceptable discrimination capacity and rather low model-fit values, but clearly showed the importance of vegetation patterns for the occurrence of solifluction
  • at a regional scale. Solifluction movement rates measured at 8 sites were combined with model parameters and the annual duration of sun hours to regionalise solifluction movement rates through an unsupervised terrain classification. For comparison, the linear
  • 2010
  • Concept ; Europeans ; Geomorphology ; Human impact ; Landscape ; Landscape dynamics ; Model ; Rwanda ; Sustainable development
  • Action anthropique ; Concept ; Dynamique du paysage ; Développement durable ; Européens ; Géomorphologie ; Modèle ; Paysage ; Rwanda
  • The dissertation deals with geomorphologic analyses of the rwandic landscape. The theoretic findings are able with the help of the geomorphologic analyses empirical to confirm. The developed model differ in two big phases of landscape development
  • 2010
  • Bank erosion ; Bibliography ; Braided channel ; Channel geometry ; Floodplain ; Fluvial dynamics ; Meander ; Model ; Riparian vegetation ; River bed ; Sedimentation ; Stream
  • Bibliographie ; Chenal anastomosé ; Cours d'eau ; Dynamique fluviale ; Erosion des berges ; Géométrie hydraulique ; Lit fluvial ; Modèle ; Méandre ; Plaine d'inondation ; Sédimentation ; Végétation ripicole
  • channel and floodplain is the outstanding problem to be solved for better understanding of the morphogenesis of rivers. Therefore combining field study, experiments and numerical modelling will lead to rapid progress in the coming decade.
  • 2010
  • Climat tempéré ; Grès ; Géostatistiques ; Géotechnique ; Modèle ; Météorisation ; Northern Ireland ; Perméabilité ; Royaume-Uni ; Sel ; Simulation ; Vitesse d'érosion
  • Erosion rate ; Geostatistics ; Geotechnics ; Mid-latitude climate ; Model ; Northern Ireland ; Permeability ; Salt ; Sandstone ; Simulation ; United Kingdom ; Weathering
  • The aim of this research is to improve the understanding of the decay dynamics of masonry materials and sandstone by weathering and to provide a quantitative and predictive basis for conceptual models of sandstone decay using geostatistics. Data
  • 2010