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  • Yet more notes on the drainage density basin area relationship
  • Les simulations de modèles aléatoires accréditent l'indépendance entre densité de drainage et surface drainée, sur un bassin homogène. Les résultats de l'A. montrent qu'il y a probablement un biais introduit par l'échantillonnage des chenaux
  • Modifications to the land use of a small catchment, including clearance, cultivation and an increase in drainage density, are shown to have influenced a number of solute characteristics. Contrasts are drawn between three source areas| an unmodified
  • subcatchment draining an area of mixed deciduous woodland, and a tile drain system and drainage ditch receiving water from cultivated areas. Not only are the modifications identified in terms of mean solute concentrations, but it is also shown that a change
  • density and channel width) change as (1) vegetation establishes on an initially bare intertidal platform and (2) sediment accretion on the intertidal platform leads to a reduction in the tidal prism (i.e. water volume that during a tidal cycle floods
  • to and drains back from the intertidal platform). Based on a time series of aerial photographs and digital elevation models, the AA. derived the channel geometric properties at different time steps during the evolution from an initially low-elevated bare tidal
  • flat towards a high-elevated vegetated marsh. They found that vegetation establishment causes a marked increase in channel drainage density.
  • The link between population density and welfare participation
  • Behaviour ; Living standard ; Participation ; Population density ; Poverty ; Social assistance ; United States
  • The AA. examine the connection between population density and household participation in the food stamp program, one of the broadest of the public assistance programs in that it serves low-income individuals in the United States. Population density
  • An estimator for the density of a sediment-induced stratified fluid
  • In this paper equations are presented to evaluate the density of water as a function of temperature, salt content, and sediment load. A nomograph based on these equations is applied to estimating the density variations of the Shapur River
  • , a sediment-laden stratified river in Southern Iran. It is illustrated that sediment gives rise to large peaks in density of the river.
  • A note on the average density function in urban analysis
  • Distance from city centre ; Population density ; Spatial structure ; Urban area
  • It is argued that the density function, commonly used in the study of urban spatial structure, is more appropriately described as the ‘marginal density function’. From such a marginal density function, it is possible to derive two types of average
  • density function, each being concerned with a particular aspect of the spatial structure of population. The first type is consistent with the standard approach to the ‘average’in economic analysis, while the second more completely takes account
  • of the urban context. The two types of average density function are examined for different underlying forms of the marginal density function. Of the two types, the second has a greater applicability than the first in the analysis of urban spatial structure.
  • Building density and interior building temperatures : a physical modeling experiment
  • Air temperature ; Applied climatology ; Model ; Radiation ; Temperature ; Urban density ; Urban settlement
  • The effect of building density on the interior temperatures of buildings is explored using scaled physical models. The urban canopy layer is modeled as a single-cube structure surrounded by a wall that represents neighboring structures. The results
  • show that nighttime cooling is primarily a function of building density, but that daytime heating depends on the interaction of density with changing model-sun relationships.
  • Choice ; Demographic change ; Methodology ; Population ; Population density ; Settlement ; Slovenia ; Statistical data
  • Population density is a quantity often used for the purposes of various evaluations and comparisons. Based on the gross density, the net density and the weighted density calculations for ten largest Slovenian settlements, the influence of the method
  • selection is demonstrated on the population density values. The results show that population density should be calculated based on inhabited areas and that the manner of calculations may drastically influence the population density values. - (IKR)
  • LONDON AND NEW YORK: RESIDENTIAL DENSITY PLANNING POLICIES AND DEVELOPMENT
  • Spatial variation of drainage density in the Palamau uplands, India
  • Barpeta-Kamrup region : an analysis of drainage density and landform
  • Population density gradients and urbanisation measurement
  • Density gradient ; Distance from city centre ; Error ; Measurement ; Suburbanization ; Urban density ; Urban population ; Urbanization
  • A structural approach to the form of the population density function
  • The central objective of this paper is to explore a comprehensive structural modeling approach that extracts analytical density functions answering questions raised by recent empirical studies.
  • Alternative explanations of the dependence of the density of centers on the density of population
  • Central places ; Centrality ; Distance ; Model ; Population density ; Service ; Spatial distribution ; Spatial system
  • Comparative trends in land-use under different levels of population density : the case of Gutu district in Zimbabwe
  • Four land tenure categories in Zimbabwe's Gutu district were selected to investigate the environmental impact of resource exploitation under different population densities. Results indicate that although high population density has initiated
  • environmental degradation in the form of deforestation, decline in grazing resources and increased erosion, similar trends have also emerged under low population densities. - (AJC)
  • Cubic spline population density functions and satellite city delimitation : the case of Barcelona
  • Barcelona ; Catalonia ; Density gradient ; Methodology ; Population density ; Second order urban centre ; Spain ; Urban density ; Urban model ; Urban population
  • Productivity and the density of human capital
  • Agglomeration ; Human capital ; Industrial structure ; Knowledge transfer ; Model ; Productivity ; Town ; United States of America ; Urban density
  • The AA. estimate a model of urban productivity in which the agglomeration effect of density is enhanced by a metropolitan area's stock of human capital. Using new information on output per worker for U.S. metropolitan areas along with a measure
  • of density that accounts for the spatial distribution of population, the AA. find that a doubling of density increases productivity by 2-4 percent. The elasticity of average labour productivity with respect with density increases with human capital
  • The aim of this study is to investigate the impact of root density and root length density of grass on the erodibility of root-permeated saturated topsoils. Three plots were established on a sandy loam. Their treatments were bare, low density
  • drilled grass and high density drilled grass, simulating different root densities. The best relationship fitting the data is the Hill curve, indicating that relative soil detachment rates decrease to very low values with an increase in root density or root
  • length density. Grass roots are very effective in reducing soil detachment rates.
  • Saguaro (Carnegiea gigantea) densities and reproduction over the northern Sonoran Desert
  • The A. proposes to determine whether there are geographic or regional patterns in population density and reproductive density in saguaro populations. He establishes how saguaro density varies over the American portion of its range, and whether
  • it is summer rainfall and climate, or the availability of nurse cover (which is related to summer rainfall) that is linked to density. He distinguishes between these confounded variables. He also relates reproductive stem density (e.g. reproductive effort per
  • Measurement of density gradients and space-filling in urban systems
  • Bristol ; Built up area ; Density gradient ; Distance from city centre ; England ; Geographical information system ; United Kingdom ; Urban density ; Urban development ; Urban morphology ; Urban structure ; Urban system
  • Clearer conception and better measurement of density and the related concept of space-filling are seen as central to applied analysis in régional science. The AA. probe the uncertain and ambiguous conception of urban density and space-filling
  • , and illustrate how new data sources permit sensitivity analysis of measurements of these properties. Arguments are illustrated with an extensive analysis of some characteristics of a large UK city (Bristol), including a sensitivity analysis of density profiles