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Упит dcterms_subject_txt:Sociology and Political Science

2375 items

  • Molecular and Isotope Composition of Biomarkers in Immature Oil Shale and its Liquid Pyrolysis Products (Open and Closed System)

    Gordana Gajica, Aleksandra Šajnovic, Jan Schwarzbauer, Aleksandar Kostić, Branimir Jovančićević, Ksenija Stojanović (2021)
    The molecular and isotopic composition of biomarkers in initial bitumen isolated from raw immature oil shale samples from the Lower Miocene Aleksinac Basin (Serbia) and liquid products (LPs) obtained by pyrolysis in open (OS) and closed systems (CS) are studied. The influence of pyrolysis type and variations of kerogen type on biomarkers composition and their isotopic signatures in LPs is determined. The molecular composition of the LPs from the OS pyrolysis is very similar to those in initial bitumen, independently ...
    ... from the OS and catagentic stage for LPs from the CS (the calculated vitrinite reflectance is 0.76 and 0.92 for samples D13 and D16, respectively). The isotope δ13C values of individual n-alkanes range between –30.2 and –33.8 ‰ with average value of –31.9 ‰ in the sample D13 and from –28.7 to ...
    ... bitumen isolated from raw immature oil shale samples and liquid products (LPs) obtained by pyrolysis in open (OS) and closed systems (CS) are studied. The influence of pyrolysis type and variations of kerogen type on biomarkers composition and their isotopic signatures in LPs is determined. Pyrolysis ...
    ... displayed notably more mature sterane and hopane distributions, which are characterized by presence of thermodynamically more stable ααα(S), αββ(S) and αββ(R) steranes, βα- and αβ-diasteranes, neohopanes (C27Ts, C29Ts), the prevalence of αβ- over βα- hopane isomers, and dominance of 22S- relative to 22R ...

  • Using Metadata For Content Indexing Within An OER Network

    Ranka Stanković, Olivera Kitanović, Ivan Obradović, Roberto Linzalone, Giovanni Schiuma, Daniela Carlucci (2014)
    ... practice and the like. As these resources need to bediscoverable, accessible and shared by potential learners across the learning environment, it is very important that they are well described and tagged in a standard way in machine readable form by metadata. Only then can they be successfullyused and reused ...
    ... (UNIKG), University of Niš (UNI) from Serbia, University of Banja Luka (UBL) and University of Tuzla (UNTZ) from Bosnia and Herzegovina and University Mediterranean (UNIM) from Montenegro. All of them develop and publish their OER independently using edX, an open-source online learning platform ...
    ... Kragujevac (UNIKG), University of Ni8 (UNI) from Serbia, University of Banja Luka (UBL) and University of Tuzla (UNTZ) from Bosnia and Herzegovina and University Mediterranean (UNIM) from Montenegro. All of them develop and publish their OER independently using edX, an open-source online learning platform ...

  • Development Of The Serbian Geological Resources Portal

    Ranka Stanković, Jelena Prodanović, Olivera Kitanović, Velizar Nikolić (2011)
    ... with keeping track of exploration and exploitation permits and works in the mineral resources field, and represents a basis for archiv- ing and efficient handling of vector, raster and related thematic alphanumeric content in one place, as well as efficient management and usage of mineral resources.8 Google ...
    ... archiving, query, retrieving, analysis and visualization of geologi- cal data. The development and implementation of GeolISS is managed by a team from the Faculty of Mining and Geology at the University of Belgrade (FMG) and funded by the Ministry of the Environment, Mining and Spatial Planning (MEMSP). The main ...
    ... archiving, query, retrieving, analysis and visualization of geological data. The development and implementa- tion of GeolISS is managed by a team from the Faculty of Mining and Geology at the University of Belgrade (FMG). Following the development of a geodatabase in ArcSDE and an ArcMap extension for data manage- ...

  • Geotechnical zoning of the terrain along the first section of E-80 highway in Serbia – SEETO route 7

    Dragoslav Rakić, Zoran Berisavljević, Irena Basarić, Snežana Bogdanović, Jovana Janković (2019)
    Part of E-80 highway that passes through Serbia (from the city of Nis to the administrative border Merdare) is 77 km long. The highway is divided into two sections: the first from Nis to Plocnik (39.4 km long) and the second from Plocnik to the administrative border with Kosovo. The route is designed through a typical plain and hilly terrain in which different geological units are dominant: crystalline schists, neogene sediments of foothills and quaternary sediments in the valley ...
    ... (clayey silts), lower weathering zone of gneiss (degraded and faulted fine grained gneiss, micaschist gneiss and amphibolite gneiss) and faulted fresh fine grained gneiss, micaschist and amphibole gneiss with appearance of marble and quartzite. In the initial zone of the section, the problem ...
    ... extremely variable along the route, and is difficult to describe in general, but has been analysed for each structure separately. In crystalline schist complex, the interaction of more compact and solid components - quartzite and marble, and softer and more degraded gneisses of different ...
    ... the Western Balkan and is part of the main regional transport network in Southeast Europe. Total length of the route is 77 km, and it is divided into two sections: the first one, 39.4 km long (ends at the Neolithic settlement Plocnik), and the second B.4 - Structures and infrastructure ...

  • Laboratory Testing of Nanosilica- Reinforced Silicate and Polyacrylamide Gels

    Irina Zahirovic, Dušan Danilović, Milica Šuput Vranjin, Miloš Tripković (2023)
    drilling fluid formulation, upstream oil and gas, fluid dynamics, fluid loss control, gel

  • INVENTS: a hybrid system for subsurface ventilation analysis

    Nikola Lilić, Ranka Stanković, Ivan Obradović (2000)
    Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full understanding and use of the obtained results require the involvement of an experienced specialist in the ventilation field. The solution was found in the creation of a hybrid system INVENTS, whose knowledge base represents a formalization of the expert knowledge in the mine ventilation field. In this paper we ...
    ... estimation ventilation simulation Design CFD Estimates estimation of gas and dust emission and temperature conditions flow process modelling using CFD Data acquis ition ventilation and psychrometric parameters ventilation and psychrometric parameters Fig. 3. Architecture of the hybrid system INVENTS ...
    ... Professor, Faculty of Mining and Geology, University of Belgrade, Djusina 7, 11.000 Belgrade 2 Bsc, Faculty of Mining and Geology, University of Belgrade, Djusina 7, 11.000 Belgrade Abstract: Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters ...
    ... the hybrid system INVENTS, as well as system structure and user interface. Keywords: hybrid systems, mine ventilation, expert systems 1. Introduction The methodology of mine ventilation planing and design in contemporary mine theory and practice differs substantially from the traditional approach ...

  • Effects of Energy Production and Consumption on Air Pollution in Serbia

    Marija Živković (2019)
    Energy production and combustion, mostly from unregulated or inefficient fuel combustion, are the single most important anthropogenic sources of air pollutant emissions. Energy sector in Serbia is highly fossil fuel intensive: 87.88% of energy consumed in Serbia is related to fossil fuels, while almost 95% of energy sources are combusted. In 2017. energy related carbon dioxide emission in Serbia is was 47.95 million tones. The main source of carbon dioxide emission was coal, responsible for almost 70% of energy ...
    energy related emissions, Serbia
    ... (firewood) for carbon monoxide and NOx from the buildings sector and oil derivates for carbon monoxide and NOx from the transport sector. Key words: energy related emissions, Serbia 1.INTRODUCTION Energy is essential to economic and social development of each community and improved quality of life of citizens ...
    ... 6%. Fossil fuels and biomass make more than 85% of the primary energy need to be transformed to heat and/or electricity through combustion processes 3, which are the main sources of atmospheric pollution 4. The need to control atmospheric emissions of greenhouse and other gases and substances leads to ...
    ... electricity and heat generation, as well as from the transport and buildings sectors 6. The transport sector is a major source of air pollutants, despite the many policy and technology advances achieved so far. It is responsible for around half of all energy related nitrogen oxide emissions and is an important ...

  • Overwiew of In-Pit Crushing & Conveying Technology in Open Pit Mines

    Ali Nasirinezhad, Dejan Stevanović, Dragan Ignjatović, Petar Marković (2021)
    The conditions under which contemporary surface mining operations is carried out obviously becoming increasingly complex. In such complex conditions, the optimization of haulage systems as the technological phase with the largest share in the total operating costs, is very important from the aspect of achieving profitability of the mining project. In a large number of cases, the application of traditional haulage systems with trucks (as the most dominant type of haulage in open pit mines) does not lead to ...
    In Pit Crushing and Conveying, IPCC, open pit mining, haulage, optimization, costs saving

  • Heavy metals in lignite and soil of Kostolac-Kovin coal basin, eastern Serbia - comparative analysis with selected cities in Serbia, region, Europe and world

    Bogoljub Vučković, Bojan Dimitrijević (2023)
    The Kostolac-Kovin coal basin with an area of 320 km2, with 5 separate layers of coal and with a total of about 5.7 Bt of geological resources and reserves represents an exceptional potential for coal production in Serbia. The coal resources listed in this way are not fully exploitable, but they represent potential for consideration. In this paper, we deal with the geochemical characteristics of coal seams and perform a comparative analysis of coal affectation on the environment. With ...
    lignite, heavy metals, concentrations
    ... pits of Stari Kostolac and Ćirikovac, after that in the surface mines of Klenovnik and Cirikovac, picture 2) and are not being excavated now; 177 2. Now in the excavation phase are some parts of 1, II and III layers (I and II layers in Kovin by underwater exploitation; II and III layers in the Drmno ...
    ... seams and perform a comparative analysis of coal af}ectation on the environment. P/ith 155 analyzes of HM from coal, 45 from ash, 165 from gravel and 30 from soil, we perform analysis of horizontal and vertical distribution of HM and comparative analysis. B/hat interests us as authors and you as ...
    ... the Velika Morava and Mlava rivers, which flow into the Danube in that area (figure 1 and 2). Itis divided into two parts by the Danube - to the south is the Kostolac Basin, and to the north ofthe Danube is the Kovin Basin (Figure 2). Geological explorations began in 1941 and continues to this day ...

  • Antioxidant and antimicrobial activity of some tetradentate Schiff bases and their Cu (II) complexes

    Aleksandar Mijatović, Milan Nikolić, Snežana Spasić, Aleksandra N. Žerađanin, Kristina Joksimović, Aleksandar Lolić, Rada Baošić (2020)
    Šifove baze i njihovi Cu(II) kompleksi su poznati po svojoj biološkoj aktivnosti. U ovom radu proučavana je antibakterijska aktivnost protiv gram-negativnih sojeva Escherichia coli, Pseudomonas aeruginosa i Staphilococcus piogenes, kao i Gram-pozitivnih Staphilococcus piogenes i Pseudomonas aeruginosa, zajedno sa antifungalnim dejstvom protiv Musperg strainilusa, A. Takođe, tehnički jednostavni i brzi testovi kao što su ABTS, HORAC i ORAC korišćeni su za ispitivanje antioksidativne aktivnosti kako bi se uporedili dobijeni rezultati sa različitim tipovima testova. Uprkos tome što je princip ...

  • Design of a sucker rod pumping system

    Ana Ponoćko (2024)
    For a long time in the history of oil production, sucker rod pumps have been the first and in many cases the only choice when it comes to mechanical extraction methods. Proper selection of each individual element of the system enables optimization, which entails benefits in the form of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The ...
    sucker rod pump, fluid production, mechanical extraction methods,, Prosper, QROD, RODSTAR
    ... of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The second part involves an analysis and calculations using the "RODSTAR", "QRod" and "Prosper" software, which ...
    ... including: maximum stress, the range of maximum and minimum stress, and the number of strokes per minute. All these factors affect material fatigue and the potential for rod failure,. In some cases, to reduce loads and investments in the lifting assembly and to increase the depth of the pump installation ...
    ... required power and capacity, and ensuring optimal system efficiency. It is also important to account for the specific characteristics ofthe reservoir and the challenges associated with equipment and system maintenance. Proper design can maximize the performance of sucker rod pump systems and reduce operational ...

  • Production information system of the Pljevlja coal mine

    Božo Kolonja, Ranka Stanković, Filip Vuković (2018)

  • The state and perspective of the natural gas sector in Serbia

    Dejan Ivezić, Marija Živković, Dušan Danilović, Aleksandar Madžarević, Miloš Tanasijević (2016)
    The strategy of long-term energy development of Serbia identifies an increase of share of natural gas in final energy consumption as one of the main aims. Serbia has signed a strategic agreement with the Russian Federation on cooperation in the oil and gas sector, within which the project South Stream pipeline is planned to be realized. In addition, the Republic of Serbia has signed the Treaty that establishes the Energy Community and accepted the obligation to implement the Energy ...
    Consumption, natural gas, scenarios of development

  • Towards translation of educational resources using GIZA++

    Ivan Obradović, Dalibor Vorkapić, Ranka Stanković, Nikola Vulović, Miladin Kotorčević (2016)
    ... University of Belgrade, 2013. [20] D. Vitas and C. Krstev. “Construction and Exploitation of X-Serbian Bitexts”. In Cristina Vertan and Walther v. Hahn (eds.) Multilingual Processing in Eastern and Southern EU Languages: Low-Resourced Technologies and Translation, pp. 207-227, Cambridge Scholars ...
    ... of them hard to translate into and with relatively weak machine translation (MT) support. Phrase-based and syntax-based SMT models are developed to address language diversity and support the language independent nature of the methodology. For high-quality MT and to add value to existing infrastructure ...
    ... combined into a feedback vector and used to refine parallel data and retrain translation models towards a more accurate second-phase translation output. The project results will be showcased and tested on the Iversity [4] MOOC platform and on the VideoLectures.NET digital video lecture library ...

  • A Description of Morphological Features of Serbian: a Revision using Feature System Declaration

    Cvetana Krstev, Ranka Stanković, Vitas Duško (2010)
    In this paper we discuss some well-known morphological descriptions used in various projects and applications (most notably MULTEXT-East and Unitex) and illustrate the encountered problems on Serbian. We have spotted four groups of problems: the lack of a value for an existing category, the lack of a category, the interdependence of values and categories lacking some description, and the lack of a support for some types of categories. At the same time, various descriptions often describe exactly the same ...
    Morphology, Lexicon, lexical database, Standards for LRs
    ... category for nouns are singular and plural (shared by all involved languages), and besides that dual (for Slovene and Czech) and count (for Bulgarian). This last value in Bulgarian is similar to ‘paukal’ in Serbian which is used with small numbers two, three and four. This value, however, does not ...
    ... gender masculine, and in the same time grammatical number singular and natural number plural. Natural gender and number, instead of grammatical gender and number are used for verbal forms sastali and su. To veče, petorica(fem/sing) džentlmenovih kolega sastali(masc/pl) su(pl) se već u osam časova ...
    ... notably MULTEXT-East and Unitex) and illustrate the encountered problems on Serbian. We have spotted four groups of problems: the lack of a value for an existing category, the lack of a category, the interdependence of values and categories lacking some description, and the lack of a support for some types ...

  • Tectono-lithostratigraphic model of the Northern Banat Miocene sediments (Pannonian Basin, Serbia)

    Dejan Radivojević, Ljupko Rundić (2017)
    ... less present then Badenian one and could be found in a very limited area. Generally, these sediments are very thin and represented with siliciclastics and limestones. °e Pannonian, Pontian, Pliocene and Quaternary sediments belong to postrift stage in the broader sense and lays unconformably over the ...
    ... less present then Badenian one and could be found in a very limited area. Generally, these sediments are very thin and represented with siliciclastics and limestones. The Pannonian, Pontian, Pliocene and Quaternary sediments belong to postrift stage in the broader sense and lays unconformably over the ...
    ... occurred simultaneously throughout the area, and it is possible to speak only about synrift and postrift stage in the broader sense (MATENCO & RADIVOJEVIĆ, 2012). In the Serbian northeastern part of Pannonian Basin, sediments of the Lower and Middle (Badenian and Sarmatian) Miocene are assigned to synrift ...

  • Callovian (Middle Jurassic) Sphriganaria (Brachiopoda) from the Jordan Valley (Middle East)

    Howard R. Feldman, Barbara V. Radulović, Fayez Ahmad (2023)
    Brachiopods, Middle Jurassic, Sphriganaria, shell microstructure, Ethiopian Province

  • Control of substructure construction of railways in the Republic of Serbia

    Dragan Lukić, Dragoslav Rakić, Irena Basarić Ikodinović (2022)
    Контрола збијености природног тла (у ископу) или збијеног у насипу при изградњи саобраћајница представља један од основних облика контроле квалитета доњег строја. Код изградње брзих саобраћајница (аутопутеви и брза железница) приоритет је постизање високог нивоа контроле извршених радова. У циљу онемогућавања диференцијалног слегања (при изградњи насипа), или промене запремине услед допунског збијања материјала, које неминовно доводе до деформација, потребно је извршити оптимално збијање материјала. У оквиру овог рада приказује се техничка регулатива која регулише контролу збијености при изградњи железничке ...
    доњи строј, техничка регулатива, насип, збијеност, контрола
    ... open track tracks and main tracks on main railways Ev2 > 80 MN/m2, Ev2/ 5 MN/m2, Rc* for the construction and improvement of open railway tracks and main tracks on regional railways Ev2 > 60 MN/m2, Ev2/Ev1 m2, Rc* for the construction and improvement of tracks on local railways and secondary tracks ...
    ... the standard and technical conditions (harmonized with the standard) determine in examination process the zone where soil homogeneity is ensured (by granulometric composition and moisture) and in statistically reliable research conditions. Perform the necessary tests and correlations and, based on them ...
    ... of the protective layer is 20 cm, and in the case of thickness > 30 cm it is installed and compacted in two layers. Load-bearing capacity at the level of the railway planum meets the following requirements: for the construction and improvement of open track tracks and main tracks on main railways Ev2 ...

  • Introduction to special section: Characterization of hydrocarbon and geothermal resource potential and carbon sequestration opportunities of the Pannonian Basin

    Balázs Németh, Gábor Tari, Gábor Bada, Dejan Radivojević, Bruno Tomljenovic, Csaba Krézsek (2018)
    нафтна геологија, геотермална енергија, Панонски басен

  • Novel cerium and praseodymium doped phosphate tungsten bronzes: Synthesis, characterization, the behavior in the Briggs-Rauscher reaction and photoluminescence properties

    Tijana Maksimović, Pavle Tančić, Jelena Maksimović, Dimitrije Mara, Marija Ilić, Rik Van Deun, Ljubinka Joksović, Maja Pagnacco (2023)
    Due to the interesting and potentially useful properties, phosphate tungsten bronzes are constantly being studied and attract a lot of attention. In the present work, two different metallic elements, belonging to the group of rare-earth metals, cerium and praseodymium, were used as a dopants for phosphate tungsten bronzes. Novel cerium and praseodymium doped phosphate tungsten bronzes were successfully synthesized and further characterized by thermal analyses, Fourier-transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy with energy-dispersive X-ray spectrometer and ...
    Electrical and Electronic Engineering, Atomic and Molecular Physics and Optics, Electronic, Optical and Magnetic Materials, Inorganic Chemistry, Organic Chemistry, Physical and Theoretical Chemistry, Spectroscopy