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Упит dcterms_subject_txt:open cut excavation

178 items

  • A comparative study of the molecular and isotopic composition of biomarkers in immature oil shale (Aleksinac deposit, Serbia) and its liquid pyrolysis products (open and closed systems)

    Gordana Gajica, Aleksandra Šajnović, Ksenija Stojanović, Jan Schwarzbauer, Aleksandar Kostić, Branimir Jovančićević (2021)
    The molecular and isotopic composition of biomarkers in initial bitumen isolated from immature (0.41% Rr) oil shale samples (Aleksinac deposit) and liquid products obtained by pyrolysis in open (OS) and closed (CS) systems are studied. The influence of pyrolysis type and variations of kerogen type on biomarkers composition and their isotopic signatures in liquid products is determined. The applicability of pyrolysis type, numerous biomarkers and carbon isotopic compositions (δ13C) of n-alkanes in liquid pyrolysates is established. Pyrolysis experiments were ...
    Uljni šejl, Aleksinac, organska supstanca, otvoreni i zatvoreni sistem pirolize, biomarkeri, izotopski sastav ugljjenika

  • Terminology Acquisition and Description Using Lexical Resources and Local Grammars

    Cvetana Krstev, Ranka Stanković, Ivan Obradović, Biljana Lazić (2015)
    Acquisition of new terminology from specific domains and its adequate description within terminological dictionaries is a complex task, especially for languages that are morphologically complex such as Serbian. In this paper we present an approach to solving this task semi-automatically on basis of lexical resources and local grammars developed for Serbian. Special attention is given to automatic inflectional class prediction for simple adjectives and nouns and the use of syntactic graphs for extraction of Multi-Word Unit (MWU) candidates for ...
    ... NNgi - A noun followed by two adjec- tives/nouns in the genitive case or in the in- strumental case; e.g. otkopavanje širokim čelom ‘broad forehead excavation’. b. NprepNp - A noun followed by a preposi- tional phrase; e.g. lanac sa grabuljama ‘chain with a rake’. 5. AXN2X – a noun preceded by an adjective ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Terminology acquisition and description using ...

  • Analogue modelling of strain partitioning along a curved strike-slip fault system during backarc-convex orocline formation: Implications for the Cerna-Timok fault system of the Carpatho-Balkanides

    Nemanja Krstekanić, Ernst Willingshofer, Taco Broerse, Liviu Matenco, Marinko Toljić, Uroš Stojadinović (2021)
    analogno modelovanje, raspodela deformacija, geometrija indentera, Černa i Timok rasedni sistem
    ... of rounded indenter’s western margin or at the north-western corner of the rectangular shaped indenter (Fig. 2a–c). The mobile plastic plate has a cut in the middle in the north-south direction (dashed green line in Fig. 2) to enable the sliding and rotation of the mobile plate along a stationary ...
    ... fixed and overlies the moving plate north of the rigid block, while underlying this moving plate to the north-west. This change takes place at the cut in the moving plate. We have chosen this configuration to prevent deformation north Fig. 2. Modelling setups. Adopted orientation is geographical ...
    ... induces the formation of new strike-slip faults with normal component of slip (e.g., fault 7 in Fig. 5j) within the evolving sedimentary basin, which cut into the orogenic wedge at the transition zone. Furthermore, the orogenic wedge gets lower and less wide with increasing amount of rotation for both ...

  • Keyword Extraction from Parallel Abstracts of Scientific Publications

    Slobodan Beliga, Olivera Kitanović, Ranka Stanković, Sanda Martinčić-Ipšić (2017)
    ... circumvent the overgeneration problem by simple tuning of the fil- ter applied to the weights during the expansion steps of setting the appropriate cut-off threshold during the extraction phase. Note that the results in this study are better for the Serbian than for the English language (see Table 2) ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Keyword Extraction from Parallel Abstracts ...
    ... extraction method should be insensitive to natural language or appropriate for extraction in different natural languages at the same time. One of the open research questions in the keyword extraction task is to develop a method that is general enough for keyword extraction in several lan- guages simultaneously ...

  • Crystallography and Surface Oxidation of Stoichiometric Arsenopyrite from Šumadija-Kopaonik Pb-Zn/Polymetallic Ore District (Serbia)

    Ivana Jelić, Aleksandar Pačevski, Aleksandar Kremenović, Aleš Šoster, Andreja Šestan, Janez Zavašnik (2023)
    The behaviour and stability of arsenopyrite largely depend on its crystal structure, but studies of crystallography and structural defects are scarce. For clarification, we investigated a series of natural arsenopyrite crystals from the polymetallic Pb-Zn-(±Cu,Ag,Au,Sb,Bi,W) Šumadija-Kopaonik ore district (Serbia) by powder X-ray diffraction (XRPD). Among them, samples from the Drenjak gold mineralisation showed near-stoichiometric FeAsS composition and were further investigated by conventional and high-resolution transmission electron microscopy methods. TEM revealed abundant planar crystallographic defects and epitaxial surface oxide layer ...
    Inorganic Chemistry, Condensed Matter Physics,General Materials Science, General Chemical Engineering, crystal structure, FeAsS, oxidation, TEM, XRPD
    ... diffraction peak at about 20 # 27” belongs to quartz (q). 2.3. Transmission Electroh Microscopy (TEM) The FeAsS samples from the Drenjak deposit were cut, formatted, and mounted in epoxy resin. The surface was ground with emery papers according, to the standard petrographical procedure [17] and pr ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs crystals Article Crystallography and Surface ...
    ... Accepted: 1 February 2023 Published: 6 February 2023 Copyright: & 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:/ / creativecommons.org//l ...

  • Anisotropic grossular–andradite garnets: Evidence of two stage skarn evolution from Rudnik, Central Serbia

    Bojan Kostić, Danica Srećković-Batoćanin, Petyo Filipov, Pavle Tančić, Kristijan Sokol (2021)
    This paper presents LA-ICP-MS data for garnets from the Rudnik skarn deposit (Serbia), which range from Grs45–58Adr40–52Alm2–3 in the core and Adr70–97Grs2–29Sps1 in the rim displaying anisotropy and zoning. In spite of wide compositional variations the garnets near the end-member of andradite (Adr > 90) are generally isotropic. Fe-rich rims exhibit LREE depletion and flat HREE pattern with weak negative Eu anomaly, including higher As and W contents. On the other side, the Fe-poorer core shows flat REE pattern ...
    grandite, garnets, skarn, Rudnik
    ... Another sample, SN-330, was taken from a quartzlatitic sill/dyke about 25 m thick, which has also been accessed by borehole. These quartz latites cut Upper Cretaceous sediments that have been metamorphosed into skarns and hornfels in the vicinity of Rudnik village (Fig. 1). The results for both ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs GEOLOGICA CARPATHICA, FEBRUARY 2021, 72, 1 ...
    ... externally induced local strain (e.g. Jamtveit et al. 1993; Ciobanu & Cook 2004). Further, according to Yardley et al. (1991), fluid flow through open systems produces oscillatory zoned garnets. Additionally, ani so tropic garnets widely range in composition whereas the garnets near the end-member ...

  • 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

  • Димензионисање система завојних пумпи

    Марија Дивац (2024)
    Овај завршни рад се бави димензионисањем система завојних пумпи (Progressive Cavity Pumps - PCP) које се широко користе у нафтној и гасној индустрији, нарочито за подизање тешких и вискозних флуида. Завојне пумпе су се показале као ефикасно решење у бушотинама са сложеним условима,захваљујући својој способности да транспортују флуиде са високим садржајем чврстих честица и гаса.Рад обухвата анализу кључних параметара као што су вискозност, густина, дубина бушотине и притисак, који су пресудни за избор одговарајуће пумпе.Применом софтверског алата извршена је ...
    завојне пумпе, димензионисање, експлоатација нафте, вискозни флуиди, софтверска симулација, PCP пумпе
    ... IIpopauyHa. Ta0ena I OTIIHITH IIOJ[ALNIH JliHaMHuKuH HHBO (m) 541 TIpurucak Ha Ke3auHry (bar) 9 TIIpurucak Ha TyOunry (bar) 10,2 Water cut (%) 80 Temmneparypa nexutmrra (?C) 68 TIpnarucax nexumrra (bar) 67,5 TIIparucak 3acuhema (bar) 68 TIIpnurucak Ha nny (bar) 32,2 IIocnenmmba ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Yuunep3urer y Beorpajny PynapckKo-reo:momiKu ...

  • Polyhedral characteristics of the cosalite-type crystal structures

    Sabina Kovač, Predrag Dabić, Aleksandar Kremenović, Aleksandar Pačevski, Ljiljana Karanović, Marko V. Rodić, Martina Tribus (2019)
    kristalna struktura, kozalit, poliedarske karakteristike

  • Groundwater management by riverbank filtration and an infiltration channel, the case of Obrenovac, Serbia

    Dušan Polomčić, Bojan Hajdin, Zoran Stevanović, Dragoljub Bajić, Katarina Hajdin (2013)

  • The influence of Al<sup>3+</sup>ion on porcine pepsin activity<i>in vitro</i>

    Vesna M. Pavelkić, Kristina R. Gopcević, Danijela Z. Krstić, Marija A. Ilić (2008)
    The in vitro effect of Al3þ ions in the concentration range 1.7·1026M–8.7·1023M on pepsin activity at pH 2, via kinetic parameters and its electrophoretic mobility was evaluated. Kinetic study demonstrated the existence of an activation effect of Al3þ at pH 2 on pepsin molecule. Kinetic analysis with respect to concentrations of haemoglobin showed that Al3þ ions increase the maximal velocity (Vmax) and kcat values rather than apparent affinity for substrate (KS) implying the non-competitive nature of activation which indicated ...
    Пепсин, алуминијум, кинетика, активација, електрофоретска мобилност
    ... pepsin solution (3:10 M ofin 0.01 M HCI, pH 2), was extensively dialyzed. Solution was placed in dialysis bags (0 mm flat width) with a molecular cut of 12 to 14 kDa (Sigma- Aldrich) and dialysed against 50mL AICI5·6H»O solution (0.01 M pH 2), for 36h at 4"C with gently stirring. All solutions ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Journal of Enzyme Inhibition and Medicinal ...

  • Understanding partitioning of deformation in highly arcuate orogenic systems: Inferences from the evolution of the Serbian Carpathians

    Nemanja Krstekanić, Liviu Matenco, Marinko Toljić, Oleg Mandić, Uroš Stojadinović, Ernst Willingshofer (2020)
    orogeneza, oroklini, višesmerna ekstenzija, transkurentna kretanja, Srpski Karpati
    ... a dominant NE direction of tectonic transport (structure 9 in Fig. 5 and Fig. 6c) and are associated with NE-SW oriented strike-slip faults, cross-cut at map scale by subsequent strike-slip deformation (structure 10 in Fig. 5). The sense of shear along closely spaced thrusts truncating Tithonian lime- ...
    ... near Kučevo (site Ku1, structure 2 in Fig. 7). Here, the previously formed cataclastic foliation in the footwall of the Supragetic thrust is cross-cut in one example by a W-dipping normal fault (Fig. 6e). Outside main shear or fault zones, this deformation is observed along individual fault planes ...
    ... Structures observed in this unit indicate that the onset of thrusting was associated with transitional ductile-brittle deformation that is cross-cut in later stages by brittle thrusts or tear faults. Such a succession of deformation during the same tectonic event indicates exhumation of the Supragetic ...

  • Mesozoic carbonate rocks in Serbia used as dimension stone

    Vesna Matović, Tijana Vojnović Ćalić (2016)
    The building industry in Serbia uses, to a great extent, imported natural stone for architectural purposes. The significance of local deposits, particularly limestones, is not adequately perceived despite the country’s abundance of these valuable resources. Therefore, this study focuses on Serbia’s Mesozoic carbonate rocks, specifically on the deposits of four selected quarries: Klisura, Skrzut, Struganik, and Tisnica. The quality and prospects of the application of these limestones has not yet been the subject of a detailed, comprehensive investigation. Therefore, ...
    Ukrasni kamen, Mezozoik, Krečnjak, Srbija, Petrografija, Fizičko-mehanička svojstva
    ... durability, wide variety of use, and easy maintenance of stone (Siegesmund and Torok 2011). New technologies, leading to substantial advances in excavation and processing, fur- ther extend modern design possibilities. Today, the global leaders in dimension stone production are Asia (50 % of world ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Bull Eng Geol Environ (2016) 75:1-12 DO!I ...
    ... the bedding with a steep dip (80%90%—adversely affect the exploitation, reducing the usable percentage of the rock mass (Fig. 1c). The Tisnica open pit quarry of natural stone is situated in Eastern Serbia, approximately 1 km from the town of Zagubica. The wide terrain, a hilly mountainous arca ...

  • Развој геолошког терминолошког речника ГеолИССТерм

    Ranka Stanković, Branislav Trivić, Olivera Kitanović, Branislav Blagojević, Velizar Nikolić (2011)
    ... sense, be viewed as indexes, glossaries, taxonomies, thesauruses and ontologies. Although the boundaries between these types are not always clear-cut, each is an extension of the one that precedes it. The seman- tic scale (Figure 1) is based on the ontological spectrum from Daconta m.c. (2003) and ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs INFOtheca, № 1, vol XII, August 2011 49 1ranka@grf ...

  • Tectonic evolution of the Vršac Mts. (NE Serbia): Inferences from field kinematic and microstructural investigations

    Uroš Stojadinović, Nemanja Krstekanić, Bojan Kostić, Marija Ružić, Aleksa Luković (2021)
    The Vršac Mts. in NE Serbia represent the key area to investigate structural relations between the Northern Serbo-Macedonian Subunit and Supragetic Unit of the Dacia Mega-Unit. The geodynamic events during the Variscan orogeny in the Late Paleozoic colligated the two units and led to their metamorphic differentiation. The Late Cretaceous extension exhumed the medium-grade Serbo-Macedonian metamorphic rocks and structurally juxtaposed them against the low-grade metamorphosed basement of the Supragetic Unit along an E-dipping shear zone, which outcrops in the ...
    severna srpsko-makedonska subjedinica, supragetikum, kinematska analiza, multifazna ekstenzionalna deformacija
    ... in the Supragetic Unit, two in the Northern Serbo-Macedonian Subunit and one at the contact between them (Fig. 5, Table 1). Each thin-section was cut parallel to the stretching lineation in the sample. We used optical microscopy to determine mineral assemblages, metamorphic grade, and micro-scale ...

  • Opremanje bušotine X zavojnom pumpom

    Milan Filipović (2024)
    Ovaj rad se bavi osnovnim pojmovima i karakteristikama zavojnih pumpi.Prikazan je sklop zavojnih pumpi i njena prateća oprema. Objašnjen je princip rada zavojnih pumpi kao i uloga svakog mašinskog elementa koji se nalazi u pumpi. Razmotrene su prednosti i nedostaci primene ovih primarnih mehaničkih metoda eksploatacije ugljovodonika. Dat je uvid u inovativna rešenja problematike primene zavojnih pumpi. Na konkretnom primeru bušotine X su prikazani problemi kao i rešenja primene ovih primarnih mehaničkih metoda u praksi. Napravljena je detaljna analiza ...
    zavojne pumpe, oprema, primarne mehaničke metode, ugljovodonici, analiza rada
    ... u tabeli 1. Tabela 1 Opšti podaci Opšti podaci Dinamički nivo (m) 541 Fritisak na kezingu (bar) 9 Fritisak na tubingu (bar) 10,2 WWater cut (%) 80 Temperatura ležišta {'C) 08 Fritisak ležišta (bar) 61,5 Fritisak zasićenja (bar) 08 Fritisak na dnu (bar) 32,2 Foslednja izmerena p ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Univerzitet u Beogradu Rudarsko-geološki ...

  • Model predviđanja potresa od miniranja na površinskim kopovima primenom simulacione metode Monte Karlo i fazi logike

    Milanka N. Negovanović (2015-06-30)
    Modeliranje predviđanja potresa tla od miniranja primenom fazi logike i metode MonteKarlo zasnovano je na podacima dobijenim terenskim merenjima potresa uzrokovanihminiranjem. Promenljive modela definisane su analizom parametara bušenja i miniranjaminskih serija, kao i velosigrama izmerenih potresa od miniranja. Iskorišćene suprednosti fazi logike u implementaciji mnogo većeg broja ulaznih i izlaznih veličina zamodeliranje u odnosu na postojeće empirijske modele. Na osnovu identičnih podataka,dobijen je regresioni model predviđanja potresa, da bi se izvršilo testiranje novogmodela. U cilju povećanja pouzdanosti modela predviđanja, ...
    model, predviđanje potresa, miniranje, površinski kop, Monte Karlo, fazilogika, regresiona analiza, FFT analiza, spektri odziva, pomeraj pukotina
    ... blasting cases. The methodology of modeling can be applied for the prediction of vibration from blasting in all open pit mines. Keywords: model, prediction of vibrations, blasting, open pit mine, Monte Carlo, fuzzy logic, regression analysis, FFT analysis, response spectra, crack displacement ...
    ... Janković, I., Zeković, D., Measurement and analysis of blast-induced vibrations in the open pit copper mine „Veliki Krivelj“ Bor, Proceedings of the XI National Conference with International Participation of the Open and Underwater Mining of Minerals, Scientific and Technical Union of mining, geology ...
    ... miniranja na površinskim kopovima primenom simulacione metode Monte Karlo i fazi logike;Model for Prediction of Blast- Induced Ground Vibrations in Open Pit Mines Using Monte Carlo Simulation Method and Fuzzy Logic Milanka N. Negovanović Дигитални репозиторијум Рударско-геолошког факултета Универзитета ...

  • Study of the Synergetic Effect of Co-Pyrolysis of Lignite and High-Density Polyethylene Aiming to Improve Utilization of Low-Rank Coal

    Ivan Kojić, Achim Bechtel, Nikoleta Aleksić, Dragana Životić, Snežana Trifunović, Gordana Gajica, Ksenija Stojanović (2021)
    Polimeri i plastika, opšta hemija
    ... for food packing was used as a source of HDPE. The plastic bag was rinsed with n-hexane to remove possible impurities (e.g., dust), dried on air, and cut using scissors into small pieces. These pieces of HDPE were mixed with NaCl (extra pure, Zorka Pharma-Hemija d.o.o., Šabac, Serbia), transferred into ...
    ... ceramic mortar, and comminuted. NaCl served as an abrasive that crushes HDPE and prevents the sticking of HDPE particles. Larger pieces were further cut with scissors, and occasionally a new portion of NaCl was added. Then, mixture of HDPE particles and NaCl was additionally finely grounded in an agate ...
    ... up to 500 ◦C. 3.2. The Yields of Pyrolysis Products Obtained by Open System Pyrolysis The yields of pyrolysis products obtained by open system pyrolysis are given in Table 1. Table 1. The yields of pyrolysis products obtained in open system pyrolysis and differences between experimental and theoretical ...

  • Using Lexical Resources for Irony and Sarcasm Classification

    Miljana Mladenović, Cvetana Krstev, Jelena Mitrović, Ranka Stanković (2017)
    The paper presents a language dependent model for classification of statements into ironic and non-ironic. The model uses various language resources: morphological dictionaries, sentiment lexicon, lexicon of markers and a WordNet based ontology. This approach uses various features: antonymous pairs obtained using the reasoning rules over the Serbian WordNet ontology (R), antonymous pairs in which one member has positive sentiment polarity (PPR), polarity of positive sentiment words (PSP), ordered sequence of sentiment tags (OSA), Part-of-Speech tags of words (POS) ...
    ... smanjenjem ne bi ni moglo da se plati! (sreća - žalost) ‘Fortunately this winter there will be no coal, gas, electricity or fuel, because with this pay cut it would be impossible to pay!’ (Fortunately – Unfortunately) By selecting a proper set of features, the precision of the ironic tweets classifier can ...
    ... 185, be_in_state 288, hyponym 20,709. 9We used the following software tools in this paper: Developing tool Eclipse Java EE IDE Luna and Apache Jena open source software development environment which allows for reasoning at the level of OWL 2 language by converting OWL rules into the Jena rules format ...

  • Hyperpycnites within the Devonian-Carboniferous flysch of the Carpatho-Balkanides (Kostadinovica, eastern Serbia)

    Miloš Radonjić (2020)
    This study presents new discoveries of vascular plants and the trace fossil Dictyodora liebeana (GEINITZ) from the Devonian–Carboniferous Kučaj-Zvonce flysch of the Carpatho-Balkanides and the implications of this fossil association for its sedimentary setting. The occurrence of the described plant debris in a deep-marine environment indicates the presence of hyperpycnites within the siliciclastic turbidites exposed at the Kostadinovica locality. The sedimentological data and the characteristics of the fossil material support the proposed model in which the sediment was at ...
    Mississippian flora, Dictyodora liebeana (GEINITZ), hyperpycnites, Kučaj-Zvonce flysch, Carpatho-Balkanides
    ... These faults (Fn in Fig. 2) have normal movements and are related to the Fss fault zone probably as a part of a transtensional system. As the excavation works in the quarry progressed, different levels of the succession were exposed and studied. Based on the sedimentary characteristics, the Kos ...
    ... на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs 2020 | 73/3 | 131–142 | 12 Figs. | www.geo ...