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A spatially varying parameter model of AFDC participation: empirical analysis using the expansion method
  • A spatially varying parameter model of AFDC participation: empirical analysis using the expansion method
  • Aide sociale ; Analyse de régression ; Analyse multivariée ; Bien-être ; Disparités régionales ; Etats-Unis ; Famille nombreuse ; Généralités sur la géographie ; Méthode d'expansion de Casetti ; Paramètre ; Population noire ; Protection sociale
  • Programme d'aide aux familles avec enfants à charge, dont les disparités régionales sont très fortes. Application de la méthode de Casetti pour rechercher les variations spatiales de l'influence de divers paramètres. Les résultats suggèrent que la
  • participation de la population noire au programme est proportionnellement plus faible dans les états du sud-est et du nord-ouest des Etats-Unis. La stabilité de l'influence des paramètres à travers l'espace ne peut donc être assumée.
Valuing a fishing day: an application of a systematic varying parameter model
  • Valuing a fishing day: an application of a systematic varying parameter model
METEOSAT observations of diurnal variation of radiation budget parameters
  • METEOSAT observations of diurnal variation of radiation budget parameters
  • L'albedo reste constant au-dessus du désert et des nuages bas ou élevés, mais varie au-dessus de l'océan. Le rayonnement infrarouge est constant au-dessus de l'océan et des nuages bas mais varie au-dessus du désert durant le jour à cause de
Spatial structure and spatial interaction : a simulation approach
  • L'A. examine les variations du paramètre d'impédance des modèles d'interaction spatiale conventionnels. La valeur négative de ce paramètre s'améliore à mesure que la configuration des destinations devient plus dispersée, que la taille des localités
  • varie, et que le degré de substituabilité des destinations diminue.
Soil development parameters in the absence of a chronosequence in a glaciated basin of the White Mountains, California-Nevada
  • Soil development parameters in the absence of a chronosequence in a glaciated basin of the White Mountains, California-Nevada
  • The primary objective here is to establish a rate curve for soil development in the White Mountains, knowing that variables such as climate, influx of eolian dust, and the rate of surface denudation have varied with time. Establishing such a rate
Tree growth and microclimatic mitigation in Mahogany-black pepper agro-forestry at Parque Ecológico de Gunma, PA, Brazil
  • . This study focuses not only on the distribution of solar radiation, which varies with canopy coverage and microclimatic parameters among sites, but also on the growth of trees covering pimenta.
  • Meteorological parameters were measured in mahogany-black pepper agro-forestry sites in Santa Bárbara do Pará, Brazil, in September 2001, in order to investigate the differences in microclimatic mitigation in relation to forest structure and growth
How to make a palsa: a field experiment on permafrost formation
  • This paper presents a natural scale field experiment on palsa formation. In this study only one parameter, which was thought to be critical one in this environment for the formation of permafrost is varied. The factor was snow depth, which
Planform dynamics of braided streams
  • parameters it depends. A series of 14 experimental runs were performed in a laboratory physical model with uniform sand, varying the discharge and the longitudinal slope. Planimetric and altimetric configurations were monitored in order to assess
  • the occurence of a steady state. A set of parameters was considered, such as the braid plain width and the number and typology of branches and nodes. Results point out that a relationships exists between braiding morphology and 2 dimensionless parameters
The influence of seasonal climatic parameters on the permafrost thermal regime, West Siberia, Russia
  • The influence of seasonal climatic parameters on the permafrost thermal regime, West Siberia, Russia
  • factors influencing the permafrost regime were spring and summer air temperatures, and in one case snow depth. However, statistical links between meteorological and permafrost parameters varied between the tundra and northern taiga zones and among
The impact of varying rainfall conditions on the quality of runoff entering Wamberal Lagoon, New South Wales, Australia
  • The impact of varying rainfall conditions on the quality of runoff entering Wamberal Lagoon, New South Wales, Australia
  • Differences in the water quality of 6 tributaries to the lagoon following wet and dry weather periods are compared for 19 parameters, including nutrients and toxicant metals. The results suggest that dry weather flows tend to transport pollutants
A quantitative evaluation of Playfair's law and its use in testing long-term stream erosion models
  • are the implications for the associated parameter estimates ? Because incision rates vary within the basin, Playfair's law only holds exactly at the junctions. These effects are more important when slopes are measured over longer distances. Finally, measurement
  • In this paper, the AA. use analytical methods and numerical models to explore 2 specific questions : how reliable is Playfair's law in the vicinity of junctions particularly when uplift rate (or baselevel lowering rate) varies in time ? and what
Kalman filter modelling of time-varying processes in urban and regional analysis in Towards the dynamic analysis of spatial systems.
  • Kalman filter modelling of time-varying processes in urban and regional analysis in Towards the dynamic analysis of spatial systems.
  • dynamique et sa méthode d'inférence, le filtre de Kalman. Examen des avantages et des limites du modèle selon que les paramètres sont statiques, évoluent de façon stochastique ou changent systématiquement. Aucune application n'est donnée, mais la
Source region effects in epidemic disease modeling: comparisons between influenza and HIV
  • An appropriate form of a multiregion disease model is fitted to the spread of the 1957 Asian influenza pandemic and then used to examine the distributions of warning times associated with varying the location of the source region. Disease parameters
Convective and dynamic instability in meridional trenches
  • The mathematical model of Raleigh convection on the rotating Earth in deep-water ocean depression is generalized for the case including the meridional temperature gradient. Critical parameters determining the convection are calculated for the Kuril
  • -Kamchatka and Japan trenches. It was noted that dynamic stability condition in bottom layers of these trenches vary within tidal cycle. Interest to the problem of water stability in deep-sea basins was stimulated by discussion on possibility to bury
Late Weichselian glaciation of the Russian High Arctic
  • recent geological investigations. The only parameter allowed to vary within this inverse procedure is the model's paleoclimate (surface air temperature and accumulation). Thus, model results indicate the thickness and dynamics of the ice sheet over
Partially constrained gravity models for predicting spatial interactions with elastic demand
  • The levels of spatial interactions with certain types of public services, such as libraries and recreation facilities, may vary with the total numbers of opportunities available. Two partially constrained gravity models are developed that provide
  • for this possibility of elastic demand. Circulation data for public libraries in Indianapolis are used to estimate the parameters of these models. The results show the presence of elasticity in the demand for library services.
The Tarfala mass balance programme
  • The purpose of the programme is to study gradients in mass balance parameters across the northern Scandinavian mountains. Storglaciären is the most important glacier in the network and is measured with high accuracy and measurement density
  • change indicates that most glaciers are close to or varying around a quasi-steady state.
The role of attractiveness functions in the determination of equilibrium solutions to production-constrained spatial interaction models
  • inattendus: distribution de l'appareil commercial dans des gares définies comme des systèmes de points, en faisant varier le paramètre de dissuasion exercée par la distance.
Jardhiti og jardfraetirannsoknir. (Géothermie et recherches géologiques)
  • La cartographie géologique et les études pétrographiques aident à définir les nombreux paramètres qui influent sur l'écoulement des eaux souterraines. Le rôle des cassures et des dykes est largement souligné. Le gradient géothermique varie de 50 C
Rainfall erosivity over Rhodesia
  • Détermination du potentiel érosif de la pluie dans une formule introduisant l'énergie cinétique et l'intensité maximum pour 30mn, semble être un paramètre applicable à de grandes régions de Rhodésie. Des données collectées pour 8000averses montrent
  • que le potentiel érosif des précipitations varie plus que les précipitations moyennes annuelles et qu'il n'y a aucune relation entre les deux. Cartographie du potentiel érosif des précipitations pour la Rhodésie.