Search results for " Spatial"

Simulation individu-centrée des mobilités résidentielles à l'aide d'un modèle dynamique prospectif (Mobisim)

2013

International audience; Dans un contexte de périurbanisation et de difficultés d'accès au logement pour certains types de ménages, la connaissance des choix résidentiels représente un enjeu majeur pour l'aménagement du territoire. La compréhension des dynamiques résidentielles et des phénomènes qui en résultent constitue un champ de recherche important, et a donné lieu au développement de nombreux outils de simulation (Raju et al. 1998; Benenson et al. 2002; Ettema et al.2011; Sener et al. 2011). Ces derniers permettent de reproduire les dynamiques ur- baines, en considérant différents scénarios de développement urbain.

Seed dispersal, braeding system, tree density and the spatial pattern of trees – a simulation approach

2002

Summary Tropical tree populations with low densities and with clumped spatial distributions are at risk in the face of fragmentation. It is therefore important to understand factors driving spatial patterns of tree populations. An important set of factors which may influence the spatial pattern of plants, could be the spatial distribution of possible seed sources such as the breeding system (monoecious, dioecious), tree density and the spatial pattern of the parent population. Another set of important factors might be dispersal of seeds away from the parent plants characterised by the mean dispersal distance and by the distribution of dispersal distances (either negative exponential or logn…

L'idée de région et le fait urbain The idea of region and the urban fact

2009

Bien que la region soit un concept multiforme, voire omniforme, le decoupage regional est le cadre privilegie de la pensee spatiale et de l'action territoriale. Or la moitie des etre humains du monde, et plus des trois quarts des europeens, habitent dans une ville. Les villes produisent plus que proportionnellement a leur poids demographique, et concentrent les activites economiques de haut niveau, particulierement la production de haute technologie, les sieges sociaux, la finance et les services aux entreprises. Dans l'economie globalisee, les performances regionales semblent etre soumises a celles des villes, et les interactions economiques regionales, nationales et mondiales sont princip…

Disparités géographiques et convergence des régions européennes : une approche par l'économétrie spatiale

2002

The aim of this dissertation is to analyze the convergence process between European regions by taking into account spatial patterns of economic activities. First, with the help of literature reviews on theoretical and empirical analyses of growth and convergence and on economic geography models, we show in chapter 1 why geographic disparities should be introduced in the study of convergence between economies. Next, the spatial statistic and econometric tools allowing to reach this goal are detailed in chapter 2. Finally, three empirical studies of the convergence process in presence of geographic disparities are carried out. They are based on a sample for per capita GDP of 138 regions, belo…

Changes in spatial and sectoral patterns of employment in Ile-de-France, 1978-1997

2006

International audience; This paper investigates the spatial distribution of employment in the region of Ile-de-France in 1978 and 1997. Exploratory spatial data analysis is used to identify employment centres and a sectoral analysis of the central business district (CBD) and sub-centres is performed. The results highlight a process of suburbanisation of employment in Ile-de-France between 1978 and 1997. A more polarised space emerges in 1997 than in 1978, with several employment centres specialised in different activities. Moreover, even if the spatial influence of the CBD declines over the study period, the CBD maintains its economic leadership by concentrating a large variety of high-orde…

Prese urbane. Studi di enunciazioni cittadine

2017

Distinguished and diverse theorists such as Benveniste, Barthes, De Certeau and Lotman have each approached the city in different ways. But while several key differences exist between them, their points of view intertwine around the concept of urban enunciation and intersect at differing points. In this study, the positions of these authors will be presented, compared and elaborated upon and the categories of linguistic enunciation of urban space will be set out, drawing from a vision of translation between languages that frequently leads, as is so often the case in Semiotics, to productive analytical models. The linguistic signs of the city will also be illustrated by examples of "short fo…

Distance decay 2.0. A global synthesis of taxonomic and functional turnover in ecological communities

2022

Caio Graco-Roza was funded by the Coordination for the Improvement of Higher Education Personnel (CAPES), the Carlos Chagas Filho Research Support Foundation (FAPERJ) and the Ella and Georg Erhnrooth Foundation; Jan Altman by research grants INTER-EXCELLENCE LTAUSA19137 provided by Czech Ministry of Education, Youth and Sports, 20-05840Y of the Czech Science Foundation, and long-term research development project no. RVO 67985939 of the Czech Academy of Sciences; Otso Ovaskainen was funded by Academy of Finland (grant no. 309581), Jane and Aatos Erkko Foundation, Research Council of Norway through its Centres of Excellence Funding Scheme (223257), and the European Research Council (ERC) unde…

Spatial pattern analysis of esca in different geographical areas of Italy.

2009

Detection of cosmic filaments using the Candy model

2004

We propose to apply a marked point process to automatically delineate filaments of the large-scale structure in redshift catalogues. We illustrate the feasibility of the idea on an example of simulated catalogues, describe the procedure, and characterize the results. We find the distribution of the length of the filaments, and suggest how to use this approach to obtain other statistical characteristics of filamentary networks.

Handling of Small Scale Structures of the Irradiance Field for Solar Energy System Analysis – A Review

2016

Abstract Satellite derived irradiance information currently approaches a status as standard input for solar energy system analysis. Due to intrinsic limitations in spatial and temporal resolution, these data fail to give information of the full dynamics of the irradiance field in space and time. The analysis of systems with sensibility to details of the temporal evolution of the irradiance field and systems with sensibility to the spatial inhomogeneity of the field require knowledge of its fine-structured. Thus, methods for a respective enhancement of the satellite derived data are needed. This contribution presents various approaches discussed for setting up respective input data.