Search results for "Spatial"
showing 10 items of 2121 documents
Compact city: agent-based simulation and sustainability assessment
2013
Shift-Invariant Canonical Polyadic Decomposition of Complex-Valued Multi-Subject fMRI Data with a Phase Sparsity Constraint
2020
Canonical polyadic decomposition (CPD) of multi-subject complex-valued fMRI data can be used to provide spatially and temporally shared components among groups with both magnitude and phase information. However, the CPD model is not well formulated due to the large subject variability in the spatial and temporal modalities, as well as the high noise level in complex-valued fMRI data. Considering that the shift-invariant CPD can model temporal variability across subjects, we propose to further impose a phase sparsity constraint on the shared spatial maps to denoise the complex-valued components and to model the inter-subject spatial variability as well. More precisely, subject-specific time …
Computing temporal sequences associated with dynamic patterns on the C. elegans connectome
2021
AbstractUnderstanding how the structural connectivity of a network constrains the dynamics it is able to support is a very active and open area of research. We simulated the plausible dynamics resulting from the known C. elegans connectome using a recent model and theoretical analysis that computes the dynamics of neurobiological networks by focusing on how local interactions among connected neurons give rise to the global dynamics in an emergent way, independent of the biophysical or molecular details of the cells themselves. We studied the dynamics which resulted from stimulating a chemosensory neuron (ASEL) in a known feeding circuit, both in isolation and embedded in the full connectome…
Les représentations spatiales de concepts scientifiques : inventaire et diversité
1994
The consultation of twelve journals (French and English language) that deal with science education, for the years 1991 to 1993, allowed us to summarize the use of spatial representations of scientific concepts in didactics research. Two main results were produced from this study : there has not been much work published with spatial representations, and what has been published is very heterogeneous. Analysis of this diversity does not always allow us to understand the authors’ objectives and obliges researchers in didactics to think about the nature and role of spatial representations in the construction of scientific knowledge.
Clubs de convergence et effets de débordements géographiques : une analyse spatiale sur données régionales européennes, 1980-1995
2007
Our article offers an econometric model of spatial interactions for the empirical analysis of growth in European regions over the period 1980-1995. The model detects spatial spillover effects and makes it possible to take account of the European economy’s strong polarization. More specifically, by factoring in both spatial autocorrelation and spatial heterogeneity, we characterize the economic polarization pattern in European regions, identify convergence clubs, and model them as spatial regimes. We estimate a two-regime model with spatially autocorrelated errors and show that the convergence process differs between the two regimes. We find a strongly significant spatial spillover effect : …
Estimation des effets de proximité dans le processus de convergence régionale : une approche par l'économétrie spatiale sur 92 régions européennes (1…
2002
L'objectif de cet article est d'examiner les conséquences de la dépendance spatiale sur la croissance régionale et le processus de convergence. Sur un échantillon de 92 régions européennes sur la période 1980-1995, nous montrons que le modèle de b-convergence absolue doit être re-spécifié en raison de la présence d'auto-corrélation spatiale. Les méthodes de l'économétrie spatiale nous orientent vers une spécification avec erreurs spatialement auto-corrélées qui nous permet de mettre en évidence un effet de débordement géographique. Nous montrons ainsi que le taux de croissance d'une région est influencé positivement par les taux de croissance des régions contiguës.
An Economic Definition of the City
1998
International audience
I corpi del virus
2020
In un articolo recentemente uscito in italiano, Bruno Latour spiega che il nuovo coronavirus illustra in modo eclatante come gli attori non umani irrompano nei nostri spazi collettivi esigendo profonde trasformazioni (e invitando a ripensare così noi stessi al loro interno). Al momento è impossibile valutare questi cambiamenti sul lungo periodo. È chiaro però che SARS-CoV-2 ha avuto subito effetti visibilissimi sulle istituzioni che danno forma al nostro universo collettivo: mercati finanziari, filiere produttive, sistemi sanitari, regolamenti, lockdown. Mi sembra che il luogo di convergenza di questi ambiti tematici sia il corpo, figura in cui si incrociano le isotopie mediche, economiche,…
Disease dispersion as a spatial interaction: The case of Flavescence Dorée
2020
International audience; Flavescence dorée is a serious and incurable vine disease transmitted by an insect vector. Focusing on its spatial diffusion and on its control with pesticides, this paper investigates the private strategies of wine producers and their socially optimal counterparts. The socially optimal regulation has to address two externalities regarding private treatment decisions: (a) the insufficient consideration of collective benefits from controlling the vector populations; (b) the failure to take into account environmental damage related to pesticide application. The probability of infection is estimated on French data from a spatial econometric specification. Three alternat…
The geography of creative industries in Europe: comparing France, Great Britain, Italy and Spain
2012
The creative economy is a holistic and multidisciplinary concept that deals with the interaction between economics, culture and technology, and centred on the production of creative contents in goods and services. One of the most relevant dimensions of creativity is the territorial one. Despite the emphasis put on the theoretical definition of creativity, the measurement of creative industries and the use of these concepts in macro units as well as in isolated case studies, it is necessary to strengthen comparative research for the identification and analysis of the kind of creativity embedded in the territory, its determinants and its patterns of concentration. This compared research relie…