The changing role of border zones in the transforming economies of East-Central Europe: The case of Poland     

Tadeusz Stryjakiewicz 《GeoJournal》1998,44(3):203-213

The geopolitical and socio-economic changes in East-Central Europe that started at the beginning of the 1990s has brought about a fundamental change in the status of frontier areas in this region. The paper examines the new transborder relationships as well as the conditions, forms and dynamics of integration processes on the example of Poland. It discusses some stimuli and barriers to cross-border co-operation, including the creation of new transborder institutional embeddedness (e.g. Euroregions). On the other hand, the paper stresses the role of the informal economy in the current development of border zones in East-Central Europe. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Minimum relative entropy and probabilistic inversion in groundwater hydrology   总被引：3，自引：0，他引：3  

Allan D. Woodbury  Tadeusz J. Ulrych 《Stochastic Environmental Research and Risk Assessment (SERRA)》1998,12(5):317-358

The similarity between maximum entropy (MaxEnt) and minimum relative entropy (MRE) allows recent advances in probabilistic inversion to obviate some of the shortcomings in the former method. The purpose of this paper is to review and extend the theory and practice of minimum relative entropy. In this regard, we illustrate important philosophies on inversion and the similarly and differences between maximum entropy, minimum relative entropy, classical smallest model (SVD) and Bayesian solutions for inverse problems. MaxEnt is applicable when we are determining a function that can be regarded as a probability distribution. The approach can be extended to the case of the general linear problem and is interpreted as the model which fits all the constraints and is the one model which has the greatest multiplicity or “spreadout” that can be realized in the greatest number of ways. The MRE solution to the inverse problem differs from the maximum entropy viewpoint as noted above. The relative entropy formulation provides the advantage of allowing for non-positive models, a prior bias in the estimated pdf and `hard' bounds if desired. We outline how MRE can be used as a measure of resolution in linear inversion and show that MRE provides us with a method to explore the limits of model space. The Bayesian methodology readily lends itself to the problem of updating prior probabilities based on uncertain field measurements, and whose truth follows from the theorems of total and compound probabilities. In the Bayesian approach information is complete and Bayes' theorem gives a unique posterior pdf. In comparing the results of the classical, MaxEnt, MRE and Bayesian approaches we notice that the approaches produce different results. In␣comparing MaxEnt with MRE for Jayne's die problem we see excellent comparisons between the results. We compare MaxEnt, smallest model and MRE approaches for the density distribution of an equivalent spherically-symmetric earth and for the contaminant plume-source problem. Theoretical comparisons between MRE and Bayesian solutions for the case of the linear model and Gaussian priors may show different results. The Bayesian expected-value solution approaches that of MRE and that of the smallest model as the prior distribution becomes uniform, but the Bayesian maximum aposteriori (MAP) solution may not exist for an underdetermined case with a uniform prior.  相似文献   

Contamination of tsunami sediments in a coastal zone inundated by the 26 December 2004 tsunami in Thailand     

Witold Szczuciński  Przemysław Niedzielski  Grzegorz Rachlewicz  Tadeusz Sobczyński  Anetta Zioła  Artur Kowalski  Stanisław Lorenc  Jerzy Siepak 《Environmental Geology》2005,49(2):321-331

Tsunami sediments deposited in a coastal zone of Thailand by the 26 December 2004 tsunami wave were sampled within 50 days after the event. All surface and ground waters in tsunami- inundated zone revealed significant salinity at that time. The tsunami sediments, composed mainly of fine to medium sand, contain significantly elevated contents of salts (Na⁺, K⁺, Ca⁺², Mg⁺², Cl and SO ₄ ⁻² ) in water-soluble fraction, and of Cd, Cu, Zn, Pb in the bioavailable fraction and As in the exchangeable fraction in relation to the reference sample. The origin of contaminants is marine, as well as litho- and anthropogenic. The salts and Pb, Zn and Cu reveal high correlation to each other and to the mean grain size (pore size and porosity). Serious environmental hazard exists in that region because, due to gentle morphology, there is a risk of migration of the contaminants into ground waters and food chain.  相似文献   

Multibeam Bathymetry and Slope Stability of Isvika Bay,Murchisonfjorden, Nordaustlandet     

Mateusz Moskalik  Tadeusz Pastusiak  Jaroslaw Tegowski 《Marine Geodesy》2013,36(4):389-398

A research expedition to the polar region of Murchisonfjorden (Nordaustlandet, Svalbard) on the research vessel Horyzont II took place in August 2009. This paper presents results from an extensive bathymetric measurement campaign of the Isvika Bay, southern part of Murchisonfjorden. The aim of this campaign was to select optimal sites for sediment sampling. A detailed analysis of the bathymetric features is performed with a special emphasis on the slope stability conditions. A simple method for identifying areas of sediment redeposition is proposed. The results confirm that the Isvika Bay has two distinct basins separated by a ridge. Both basins display flat central regions surrounded by steep slopes with gullies. In addition, results of analysed Quaternary geological data have indicated that the area was affected by ice repeated glacial activity in the past and that there is no morphological form typical for glacier erosion and sedimentation.  相似文献