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21.
Aleksandra Gajić Nikola Krunić 《Geografisk tidskrift / udgivet af Bestyrelsen for Det Kongelige danske geografiske selskab》2013,113(2):160-172
Abstract: Identification of urban and rural areas has been a widely present topic in the past decades, both in scientific research and in the policy and practice of spatial/regional development and territorial governance. The internationally accepted OECD definition does not produce appropriate results that are able to include the multidimensionality of these territories. In this context, the aim of this paper is the analysis and selection of relevant criteria and indicators of urbanity/rurality that may be significant for the establishment of a methodological framework for identifying urban and rural areas in Serbia. Multivariate analysis (PCA, FA and CA) was used to group local self-government units (LSGU) in Serbia that share similar characteristics. The research resulted in five types of areas which indicate that rural and urban areas in Serbia are very diverse in terms of physiogeographical, socio-economic and functional characteristics. The results of this paper offer a more detailed analysis based on scientifically and empirically selected indicators and can be applied in the practice of spatial and urban planning, and in the adaptation of strategic development documents at the regional or national level. 相似文献
22.
Strontium isotope identification of water mixing and recharge sources in a river system (Oder River,central Europe): A quantitative approach 
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下载免费PDF全文 Mateusz Zieliński Jolanta Dopieralska Zdzislaw Belka Aleksandra Walczak Marcin Siepak Michał Jakubowicz 《水文研究》2018,32(16):2597-2611
This study uses Sr isotope composition (87Sr/86Sr) and Sr content of waters of the Oder, one of the largest rivers in central Europe, to fingerprint natural and anthropogenic contributions to its Sr budget and to evaluate water mixing processes in its hydrological system. It also demonstrates a simple method of quantifying natural and anthropogenic Sr inputs in the watershed. The method has potential for environmental and archaeological research because past Sr geochemistry of river water can easily be reconstructed. For the first time, a catchment‐scale impact of anthropogenic sources on the Sr budget of a middle‐size river is shown in a quantitative way. The water of the Oder is characterized by a relatively uniform Sr isotope composition, from 0.7100 to 0.7108, contrasting with strong variations in Sr concentration, from 0.25 to 1.27 mg/L. There is a general seasonal trend in variability, with waters becoming more radiogenic and dilute with respect to the Sr in the spring time. This Sr systematics differs significantly from the Sr budgets of the majority of the Oder tributaries that exhibit more radiogenic composition and systematically lower Sr concentrations. A mixing scenario in the Oder involves Sr contribution from four principal water sources: (a) shallow ground waters with Sr derived from near‐surface weathering of silicates, (b) moderately radiogenic mine waters from the Upper Silesian Coal Basin, (c) unradiogenic mine waters from the Permian sequence of the copper district, and (d) unradiogenic ground waters from shallow‐seated Palaeogene, Neogene, and Mesozoic aquifers. The Sr budget of the Oder is primarily controlled by inputs of dissolved Sr from anthropogenic sources, which overprint the natural background, controlled by geology. Thus, about 47.5% of Sr originates from agriculture, industrial, and municipal additions, 31.5% from mine water inputs, and only 21% from natural sources, that is, rock weathering and atmospheric precipitation. Reconstruction of the past Sr chemistry of the Oder reveals that its present‐day Sr isotope composition is temporary and significantly different from that of the preindustrial times. 相似文献
23.
Zoran T. Rakicevic Aleksandra Bogdanovic Dimitar Jurukovski Peter Nawrotzki 《Bulletin of Earthquake Engineering》2012,10(3):1049-1073
A shaking table testing of a 16.6 t five storey steel frame structure with and tuned mass damper (TMD) named as Tuned Mass Control System (TMCS) installed at the top has been carried out in the Dynamic Testing Laboratory at the Institute of Earthquake Engineering and Engineering Seismology (IZIIS) in Skopje, Republic of Macedonia. For estimation of the effectiveness of Tuned Mass Control System (TMCS) large number of shaking table experiments have been performed. Simulating different earthquake time histories on the model structure with and without TMCS it has been demonstrated that this system is capable to reduce the responses in order from 10% to more than 50% depending on the frequency content of the seismic input and the corresponding sensitivity of the structure. Given a high quality analytical model of a structure and a dynamic absorber, a series of variant analyses have been performed within the study to investigate the effect of the individual parameters and evaluate the efficiency of the dynamic absorber. The analyses have been performed to define the effect of the location of the absorber, also, upon the dynamic behaviour of the structure in the case the absorber is installed at the different level (storey) of the structure. Comparative analysis of the structure with TMCS having optimally tuned its mechanical properties versus structure that has TMCS having the same mechanical properties as tested specimen showed that the TMCS additionally improves the structural behaviour, depending on frequency content of earthquake excitation. 相似文献
24.
Ultrasonic treatment (sonication) of the Szczecin Lagoon sediment samples processed for examination of cladoceran remains
is described. As opposed to cladoceran remains from non-sonicated sediment, those extracted from the ultrasound-treated samples
were clean, easily stained, clearly visible in microscope slides and identifiable. Sonication is therefore recommended as
an aid in rendering cladoceran remains free of adhered particles that obscure the specimens and complicate their identification
in some sediments. 相似文献
25.
The need to adapt to climate change impacts, whilst simultaneously limiting greenhouse gas emissions, requires that the government’s efforts are joined by public action. In England and Wales, housing contributes significantly to the emissions and many properties are at risk of flooding. This paper investigates the preparedness of homeowners in England and Wales to make changes to their homes in response to the predicted effects of climate change. A telephone survey of 961 homeowners investigated their interest in purchasing mitigation and adaptation improvements against their concern about climate change, awareness of flood risk and attribution of responsibility for action. Whilst the majority of homes had some energy-saving improvements, few were found to have property-level flood protection. The high levels of awareness about climate change and flooding were coupled with the perception of risks as low. Whilst some respondents accepted personal responsibility for action, most believed that the authorities were responsible for flood protection, and would not pay the costs required to make their home more energy-efficient and better prepared for the eventuality of floods. The results suggest that there is scope for further improvement of energy-saving measures, and that the levels of adoption of flood-protection measures are very low. Multi-faceted strategies, including more effective communication of risks and responsibilities, incentives, and material support for the poorest, will need to be developed to overcome the current reluctance by homeowners to invest in flood-protection measures and further energy conservation solutions in the future. 相似文献
26.
Aleksandra Kiecak Grzegorz Malina Ewa Kret Tadeusz Szklarczyk 《Environmental Earth Sciences》2017,76(6):248
Selection of effective groundwater remediation scenarios is a complex issue that requires understanding of contaminants’ transport processes. The effectiveness of cleanup measures may be verified by fate and transport numerical modeling. The goal of this work was to present the usefulness of fate and transport modeling for planning, verification and fulfillment of effective groundwater remediation methods. Selection methodology was developed, which is based on results of numerical flow and transport modeling. A field site located in south-east Poland was selected as a case study, in which groundwater contamination of trichloroethene and tetrachloroethene was detected. The results indicated that “pump and treat” was the most effective among the studied remediation methods, followed by permeable reactive barrier and in situ chemical oxidation. Natural attenuation-based remediation was demonstrated to be the least suitable, as it requires the longest time to reach predefined remediation goals, principally due to low sorption capacity and unfavorable hydrogeochemical conditions for biodegradation. Fate and transport numerical modeling allowed simulating different remediation strategies, and thus the decision-making process was facilitated. 相似文献
27.
Five species belonging to five genera and an unidentified rhynchonellid have been recognised in a Late Eocene (Priabonian) brachiopod assemblage from Castelnuovo in the Euganean Hills, north-eastern Italy. One genus and two species are new, i. e. Venetocrania euganea gen. et sp. nov. and “Terebratula” italica sp. nov. Orthothyris pectinoides (von Koenen 1894) is recorded for the first time from Italy. The other species are Terebratulina sp. cf. T. tenuistriata (Leymerie 1846) and Lacazella mediterranea (Risso 1826), both already known from the Italian Eocene. 相似文献
28.
Milan M. Ćirković Srdjan Samurović Aleksandra Djorić 《Astrophysics and Space Science》2000,274(4):867-875
The discussion of the relationship between cooling radius in two-phaseadiabatic halo models and observationally established maximal radiusof absorption in luminous galaxies at low redshift is presented. It isof paramount importance that any viable model of the halo is able toreproduce empirical value of the absorption cross-section of normalgalaxies and its scaling with luminosity. Several ways for bringingthe theoretical and observational values into agreement are outlined.It is of great methodological importance to fully assess the difficultiesany model is likely to encounter when testing predicted extent ofabsorption and column density distribution against recently obtainedlow-redshift Ly absorption data. 相似文献
29.
Sheshov V. Apostolska R. Bozinovski Z. Vitanova M. Stojanoski B. Edip K. Bogdanovic A. Salic R. Jekic G. Zafirov T. Zlateski A. Chapragoski G. Tomic D. Zurovski A. Trajchevski J. Markovski I. 《Bulletin of Earthquake Engineering》2022,20(2):795-817
Bulletin of Earthquake Engineering - At 03:56 local time on November 26, 2019, an earthquake with a Mw = 6.4 struck western part of Albania. The duration of the tremor lasted less than... 相似文献
30.
Quaternary climate change and Heinrich events in the southern Balkans: Lake Prespa diatom palaeolimnology from the last interglacial to present 总被引：1，自引：0，他引：1