Search results for "spatial data"
showing 10 items of 30 documents
Exploiting historical rainfall and landslide data in a spatial database for the derivation of critical rainfall thresholds
2017
Critical rainfall thresholds for landslides are powerful tools for preventing landslide hazard. The thresholds are commonly estimated empirically starting from rainfall events that triggered landslides in the past. The creation of the appropriate rainfall–landslide database is one of the main efforts in this approach. In fact, an accurate agreement between the landslide and rainfall information, in terms of location and timing, is essential in order to correctly estimate the rainfall–landslide relationships. A further issue is taking into account the average moisture conditions prior the triggering event, which reasonably may be crucial in determining the sufficient amount of precipitation.…
Analyse spatiale des disparités régionales dans l'Europe élargie
2004
The aim of this paper is to study the regional inequalities in the enlarged European Union using Exploratory Spatial Data Analysis applied to per capita GDP for 258 regions of EU27 over the period 1995-2000. Strong evidence in favor of global and local autocorrelation as well as spatial heterogeneity is found for the wealth distribution. We also show that the enlargement process leads to a new North-West - East polarization scheme instead of the previous results obtained in the literature highlighting a North-South polarization scheme. Implications for regional development and cohesion policies are finally explored.
Conditional predictive inference for online surveillance of spatial disease incidence
2011
This paper deals with the development of statistical methodology for timely detection of incident disease clusters in space and time. The increasing availability of data on both the time and the location of events enables the construction of multivariate surveillance techniques, which may enhance the ability to detect localized clusters of disease relative to the surveillance of the overall count of disease cases across the entire study region. We introduce the surveillance conditional predictive ordinate as a general Bayesian model-based surveillance technique that allows us to detect small areas of increased disease incidence when spatial data are available. To address the problem of mult…
Sharing spatial data with a 3D component as a collaborative and dissemination tool for archaeology: conceptual challenges and technical issues
2018
International audience; Due to INSPIRE directive, various spatial data infrastructure (SDI) were developed to support research activities. In practice, these toolsremain underexploited by researcher for many reasons. First, their use is time-consuming and researchers usually consider that they provide noimmediate benefits. Second, their use is often complex and needs a substantial investment for researchers who have a limited expertise in spatial data. Finally, often based on 2D GIS environment, they do not provide an adequate tool for collaborative research in archaeology. From this experience, an interdisciplinary team designed and developed an SDI based on GeOrchestra, synchronized with …
Verso una dimensione narrativa delle mappe
2021
Tra il pensiero e la costruzione dell’architettura il disegno ha un ruolo baricentrico per connettere i diversi protagonisti di una realizzazione e per coinvolgere la collettività facendo percepire inedite prospettive. La scrittura si rivela utile per esplicitare ciò che nella grafica è sotteso e per stabilire un ordine nuovo nel ragionamento progettuale. I rapporti fra segni e significati si moltiplicano nei sistemi informativi recenti in cui si ha la sensazione di poter dire moltissimo (dati numerici e spaziali) ma a volte sfugge quella sintesi indispensabile per una interpretazione concreta, finalizzata alla costruzione di possibili esperienze fisiche. Per l’esplorazione dell’uso di dive…
AMUN: An Object Oriented Model For Cooperative Spatial Information Systems
1997
International audience; The diversity of spatial information systems promote the need to integrate heterogeneous spatial or geographic information systems (GIS) in a cooperative environment. We present an on going research project, called ISIS (Interoperable Spatial Information System), which aims to build an environment to support interoperability of GIS by interconnecting spatial data repositories and spatial processing resources. Our solution combines techniques from traditional interoperable information systems, spatial data modeling and distributed object oriented databases. While object oriented data modeling impact has been studied in spatial databases, research in model for distribu…
Spatial joins
2019
The spatial join is a popular operation in spatial database systems and its evaluation is a well-studied problem. This paper reviews research and recent trends on spatial join evaluation. The complexity of different data types, the consideration of different join predicates, the use of modern commodity hardware, and support for parallel processing open the road to a number of interesting directions for future research, some of which we outline in the paper.
Knowledge Discovery and Digital Cartography for the ALS (Linguistic Atlas of Sicily) Project
2009
In this paper the latest developments of the ALS (Linguistic Atlas of Sicily) project are presented. The ALS project has the purpose to define methodologies and tools to allow researches in the socio-linguistic field. Different types of variables (both quantitative and qualitative) are involved. The whole framework is based on the definition of ontology-based applications for the creation, retrieval, manipulation and browsing of related data. To this aim, some mapping processes have been defined. The framework eventually shows the result in many ways including spatial maps. The on-going collaboration process is a perfect example a domain hybridizing process, enabling the training on-the-fie…
Dealing with spatial data pooled over time in statistical models
2012
Recent developments in spatial econometrics have been devoted to spatio-temporal data and how spatial panel data structure should be modeled. Little effort has been devoted to the way one must deal with spatial data pooled over time. This paper presents the characteristics of spatial data pooled over time and proposes a simple way to take into account unidirectional temporal effect as well as multidirectional spatial effect in the estimation process. An empirical example, using data on 25,357 single family homes sold in Lucas County, OH (USA), between 1993 and 1998 (available in the MatLab library), is used to illustrate the potential of the approach proposed.
Convergence of European regions (an approach by spatial econometrics)
2000
The aim of this paper is the analysis of spatial dependence in convergence processes applied to European regions. First, we apply the recently developed exploratory spatial data analysis (Anselin, 1996) in order to describe more precisely the geographical dynamics of European regional income growth patterns. New insights are brought to the usual cr-convergence measure, which hides geographical patterns that may fluctuate over time. Second, we test the presence of spatial autocorrelation in /^-convergence models by using spatial econometrics methods (Anselin, 1988 ; Anselin and Florax, 1995). We compare the results with and without spatial autocorrelation in order to assess the effect of geo…