Search results for "spatial analysis"
showing 10 items of 206 documents
Source Detection in an Outbreak of Legionnaire’s Disease
2006
Spatial statistics have broadly been applied, developed and demanded from the field of epidemiology. The point process theory is an appropriate framework to analyse the spatial variation of risk of disease from information at individual level.
Spatial Patterns of Regional Income Inequality Then and Now
2018
In this chapter an important element characteristic of territorial inequality is examined: the presence of geographical patterns, that is, the grouping of neighbouring regions into clusters of wealth or poverty. The descriptive evidence provided by the maps is supplemented with spatial autocorrelation statistics to test for the presence of spatial clustering. The analysis aims to identify when exactly the geographical patterns that characterize regional inequality in Spain today took shape. Then some hypotheses as to the causes are established. Finally, the chapter analyses whether the clusters of poor or rich regions continue uninterrupted beyond national borders to include regions of Port…
A Semantic Web Approach for Geodata Discovery
2013
International audience; Currently, vast amounts of geospatial information are o ffered through OGC's services. However this information has limited formal semantics. The most common method to search for a dataset consists in matching keywords to metadata elements. By adding semantics to available descriptions we could use modern inference and reasoning mechanisms currently available in the SemanticWeb. In this paper we present a novel architecture currently in development in which we use state of the art triplestores as the backend of a CSW service. In our approach, each metadata record is considered an instance of a given class in a domain ontology. Our architecture also adds a spatial dat…
Use of Geospatial Analyses for Semantic Reasoning
2010
International audience; This work focuses on the integration of the spatial analyses for semantic reasoning in order to compute new axioms of an existing OWL ontology. To make it concrete, we have defined Spatial Built-ins, an extension of existing Built-ins of the SWRL rule language. It permits to run deductive rules with the help of a translation rule engine. Thus, the Spatial SWRL rules are translated to standard SWRL rules. Once the spatial functions of the Spatial SWRL rules are computed with the help of a spatial database system, the resulting translated rules are computed with a reasoning engine such as Racer, Jess or Pellet.
LKS-92 Coordinates Transformation to ITRF2000
2014
LKS-92 is Latvian geodetic coordinate system used as an EUREF89 realization in Latvia. LKS-92 is official coordinate system for procuring of essential geospatial data. For aeronautical and other purposes ITRF2000 is used in publication of geospatial data. Research is done to obtain transformation parameters from LKS-92 realization epoch 1992.75 through LatPos to ITRF2000 epoch 2000.00. Valuation of two different coordinate adjustment strategies and accuracy of parameters is done. Results of research could be used for transformation from LKS-92 to ITRF2000 for all kind of geospatial data.
Geomorphologic Risk Modelling of the Sibiu Depression Using Geospatial Surface Analyses
2011
Extreme events in general, and the geomorphologic ones in particular, are highly topical problems. There were addresses by many researchers in the field of geology and physical geography (more specific by the climatologists and geomorphologists), but also by biologists, chemists, ecologists, etc. These are studied through the analysis of some types of processes and production mechanisms, and secondly by the effects they create on other environmental subsystems.
ASSESSMENT OF ECOSYSTEM SERVICES FOR PLANNING OF GREEN INFRASTRUCTURE AT THE REGIONAL LEVEL
2019
Ecosystem services (ES) are defined as the benefits that human beings derive from ecosystem functions. Assessment and mapping of these benefits are crucial for sustainable environmental planning and future natural capital. Green infrastructure (GI) is natural or semi-natural territories that provide wide range of ES. Human affected ecosystems tend to fail to provide certain sets of ES due to the trade-offs among those services, which could be mitigated through implementation of GI. Mapping of ES, as well as assessing the interactions among various ES and analysing their supply potential’s cold/hot spots considerably enhances and substantiates the planning process of GI, particularly at the …
Spatial autocorrelation and the selection of simultaneous autoregressive models
2007
Aim Spatial autocorrelation is a frequent phenomenon in ecological data and can affect estimates of model coefficients and inference from statistical models. Here, we test the performance of three different simultaneous autoregressive (SAR) model types (spatial error = SAR err , lagged = SAR lag and mixed = SAR mix ) and common ordinary least squares (OLS) regression when accounting for spatial autocorrelation in species distribution data using four artificial data sets with known (but different) spatial autocorrelation structures. Methods We evaluate the performance of SAR models by examining spatial patterns in model residuals (with correlograms and residual maps), by comparing model para…
Species richness of migratory birds is influenced by global climate change
2007
Aim Global climate change is increasingly influencing ecosystems. Long-term effects on the species richness and composition of ecological communities have been predicted using modelling approaches but, so far, hardly demonstrated in the field. Here, we test whether changes in the composition of bird communities have been influenced by recent climate change. Location Europe. Methods We focus on the proportion of migratory and resident bird species because these groups are expected to respond differently to climatic change. We used the spatial relationship between climatic factors and bird communities in Europe to predict changes in 21 European bird communities under recent climate change.…
Scale-related patterns in the spatial and environmental components of stream macroinvertebrate assemblage variation
2007
Aim We examined the relative contributions of spatial gradients and local environmental conditions to macroinvertebrate assemblages of boreal headwater streams at three hierarchical extents: bioregion, ecoregion and drainage system. We also aimed to identify the environmental variables most strongly related to assemblage structure at each study scale, and to assess how the importance of these variables is related to regional context and spatial structuring at different scales. Location Northern Finland (62–68° N, 25–32° E). Methods Variation in macroinvertebrate data was partitioned using partial canonical correspondence analysis into components explained by spatial variables (nine terms…