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Relationships between environmental and social factors have long been studied by geographers.Nowadays,GIS-aided statistical analysis provides new tools to explore these relationships.In order to detect the impact of topography on social factors,we selected the country of Montenegro as a case example due to its high topographic variability.We compared the spatial pattern of population,settlements and ethnic minorities to physical geographic factors,especially to topography,but lithology and land cover data were also taken into consideration.We found that certain factors are closely correlated,e.g.the settlement density linearly decreases with elevation,while the characteristic settlement area shows an exponential increase upwards.The population density is not related to absolute elevation,but it is in close correlation with height（i.e.elevation relative to the local minimum）.Population change and illiteracy are also topography-related social factors.On the contrary,the variable ethnic pattern of Montenegro is influenced by historical,political and economic effects rather than by environmental factors or topographic features.As a conclusion we state that in the scale of a country or a region,the environment can strongly impact some social factors. 相似文献
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Jenő Reiczigel Katharina Brugger Franz Rubel Norbert Solymosi Zsolt Lang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2010,24(3):455-462
The Usutu virus is an arbovirus transmitted by mosquitoes and causing disease in birds. The virus was detected in Austria
for the first time in 2001, while a major outbreak occurred in 2003. Rubel et al. (2008) developed a nine-compartment deterministic SEIR model to explain the spread of the disease. We extended this to a hierarchical
Bayes model assuming random variation in temperature data, in reproduction data of birds, and in the number of birds found
to be infected. The model was implemented in R, combined with the FORTRAN subroutine for the original deterministic model.
Analysis was made by MCMC using a random walk Metropolis scheme. Posterior means, medians, and credible intervals were calculated
for the parameters. The hierarchical Bayes approach proved to be fruitful in extending the deterministic model into a stochastic
one. It allowed for Bayesian point and interval estimation and quantification of uncertainty of predictions. The analysis
revealed that some model parameters were not identifiable; therefore we kept constant some of them and analyzed others conditional
on them. Identifiability problems are common in models aiming to mirror the mechanism of the process, since parameters with
natural interpretation are likely to exhibit interrelationships. This study illustrated that Bayesian modeling combined with
conditional analysis may help in those cases. Its application to the Usutu model improved model fit and revealed the structure
of interdependencies between model parameters: it demonstrated that determining some of them experimentally would enable estimation
of the others, except one of them, from available data. 相似文献
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Asteroids can be considered as sources of contamination of point sources and also sources of confusion noise, depending whether their presence is detected in the image or their flux is under the detection limit. We estimate that at low ecliptic latitudes, ≈10,000–20,000 asteroids/sq. degree will be detected with an E-ELT like telescope, while by the end of Spitzer and Herschel missions, infrared space observatories will provide ≈100,000 serendipitous asteroid detections. The detection and identification of asteroids is therefore an important step in survey astronomy. 相似文献
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