AIDS ; Africa ; Diffusion ; Epidemic ; Health ; Medical geography ; Simulation
A pedagogic simulation with profiles of high-risk characteristics is used to illustrate the path and means by which AIDS is diffusing across sub-Saharan Africa, the region most severely affected by this pandemic. - (DWG)
Climatology ; Global change ; Human impact ; Model ; Ocean atmosphere interaction ; Precipitation ; Simulation ; Spatial variation ; Statistics
This article reviews the problems of testing the accuracy of climate models at simulating one particular element of climate on different temporal and spatial scales, namely, precipitation. The discontinuous nature of precipitation in time and space
makes this climate variable perhaps the most challenging one for climate models to simulate. There are two complementary components to this review: how well do models simulate the present precipitation climatology of the earth? and, how well do we know
La construction du coupleur universel Oasis (Ocean, Atmosphere, Sea-Ice and Sols) a donné une impulsion nouvelle aux essais de simulation du système couplé océan-atmosphère. On détaille une expérience simulant la dynamique de l'océan Pacifique
Regional economic growth by policy-induced capital flows:II. Policy simulation results
Economie régionale ; Facteur de production ; Fonction de production ; Migration interrégionale ; Modèle ; Politique économique ; Productivité ; Revenu ; Simulation
Economic policy ; Factor of production ; Income ; Interregional migration ; Model ; Production fonction ; Productivity ; Regional economy ; Simulation
de production (actifs et passifs). Simulation des ajustements actifs. Discussion sur les effets induits des politiques.
Arid area ; Desert ; Eolian pavement ; Grain size distribution ; Model ; Precipitation ; Raindrop erosion ; Simulation ; Soil erosion ; Splash ; Vegetation
of the model to soils in areas of existing pavement initially simulates the formation of pavements, but the changing sediment size distributions lead to the subsequent destruction of these modelled surfaces. An improved model that accounts for the feedback
Modelling the errors in areal interpolation between zonal systems by Monte Carlo simulation
Analyse de régression ; Analyse numérique ; Analyse spatiale ; Erreur ; Méthode de Monte Carlo ; Méthodologie ; Simulation ; Statistique
Error ; Methodology ; Monte Carlo analysis ; Numerical analysis ; Regression analysis ; Simulation ; Spatial analysis ; Statistics
Problème du transfert de données d'un zonage régional à un autre, les deux zonages étant géographiquement incompatibles. Imprécision et possibilité d'erreurs. Exposé de la méthode de simulation: unités modifiables. Propriétés de la distribution de
Channel geometry ; China ; Discharge ; Experimentation ; Fluvial dynamics ; Fluvial erosion ; Fluvial processes ; Human impact ; Model ; Simulation ; Watershed
effect but different structure based on systematic theory, it is possible to study properties, formation and processes in fluvial dynamic geomorphology. A new research method, which is a combination of mathematical simulation by computer with physical
This paper presents Atmospheric General Circulation Model (AGCM) simulations of the effect of orbital variations on northern hemisphere extratropical climates. The goal is to use these simulations to help explain observed paleoenvironmental changes
during the last interglaciation. The simulations are offered as sensitivity studies, i.e., the AA. focus on the effects of orbital variations and do not consider the possible further effects of other climatic controls such as atmospheric CO2. Simulated
Consommation d'énergie ; Demande ; Electricité ; Energie ; England ; Prévision ; Royaume-Uni ; Scénario ; Simulation ; West Midlands
Demand ; Electricity ; Energy ; Energy consumption ; England ; Forecast ; Scenario ; Simulation ; United Kingdom ; West Midlands
Présentation d'un modèle qui simule la consommation d'électricité à l'échelle d'une région. Application aux Midlands de l'Ouest. Les AA. montrent en quoi ce modèle est différent des approches économétriques conventionnelles.
The AA. describe an experiment in which subjects learn either from a map or from a computer-simulated walk through an environment. Tests of route reproduction , cue location, orientation, and directional knowledge are undertaken.
Simulation modeling and statistical classification of escarpment planforms
Nearly horizontal sedimentary sequences are typically eroded into escarpments capped by resistant rock layers. These escarpments record in planform the spatial variation in erosional processes. Simulation models have been constructed of scarp
development by three processes, scarp backwasting, fluvial erosion, and groundwater sapping, acting singly or in combination. The simulated scarps are statistically compared with natural scarps using a multivariate suite of variables measuring planform shape.
Agriculture ; Environment ; Forecast ; Germany ; Information system ; Model ; Simulation
(240 regions for the former Republik of Germany). In addition to ex post simulations for the years 1979, 1983 and 1987 (an soon, 1991), the model is used to simulate different agriculytural and environmental policy scenarios in order to analyse
This study presents results of microplot experiments with a rainfall simulator on soils of a small hydrologic catchment area in south-central Turkey. The objective was to establish the magnitude of the soil erodibility and infiltration variation
la normale. Résultats complétés par des analyses de sensibilité. Comparaison avec Los Angeles. Des simulations mesurent les effets de la décentralisation de l'emploi sur le comportement des migrants.
Modélisation de la dynamique urbaine, la ville étant considérée comme un système capable de s'auto-organiser. L'accent est mis sur le caractère complexe et relativement imprévisible de la ville. Exercices de simulation pour décrire le processus
This paper contributes to the knowledge of the influence of fire and aspect on the hydrological and erosional response of soils in a typical Mediterranean environment. It presents measurements of soil aggregation parameters and rainfall simulation
Les modèles de chaînes de logements vacants: simulation des transferts des possibilités de logements vacants à l'intérieur des secteurs du marché du logement urbain. Analyse de données relatives à trois villes suédoises: mobilité résidentielle
Local finance ; Local taxation ; Model ; Simulation ; Spatial equilibrium ; Urban administration ; Urban economy ; Value added
of the simulations reveal that there exists a well-defined sales tax Laffer curve and an optimal revenue-maximising tax rate. Incorporation of the production side of the economy strengthens the case for a higher sales taxation.
Agroclimatologie ; Bilan hydrique ; Cycle de l'eau ; Eau du sol ; Evapotranspiration ; Modèle ; Simulation ; Sol
Agroclimatology ; Evapotranspiration ; Model ; Simulation ; Soil ; Soil water ; Water budget ; Water cycle
Présentation d'un modèle de bilan hydrique au pas de temps décadaire, implanté sur micro-ordinateur et permettant un suivi opérationnel du bilan hydrique des cultures à l'échelle départementale. Ce modèle simplifié simule de façon satisfaisante la