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778 items
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Effect of natural gas composition on methane number: A case of gas reservoirs in Serbia
Natural gas is considered as the most environmentally acceptable fossil fuel, thus it is an alternative to petroleum derivate, dominantly used in internal combustion engines. Physical properties of a fuel as well as behavior during combustion process are affected by its composition. This article presents analysis of effect of natural gas composition on methane number (MN), conducted for natural gas deposits in Serbia. For empirically determination of MN: California air resources board (CARB) method and Linear and Anstalt für ...Marija Živković, Milica Ivić, Dejan Ivezić, Aleksandar Madžarević. "Effect of natural gas composition on methane number: A case of gas reservoirs in Serbia" in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects (2017). https://doi.org/10.1080/15567036.2017.1403518
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Synthesis of MnCo2O4 nanoparticles as modifiers for simultaneous determination of Pb(II) and Cd(II)
The porous spinel oxide nanoparticles, MnCo2O4, were synthesized by citrate gel combustion technique. Morphology, crystallinity and Co/Mn content of modified electrode was characterized and determined by Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction pattern analysis (XRD), simultaneous thermogravimetry and differential thermal analysis (TG/DTA). Nanoparticles were used for modification of glassy carbon electrode (GCE) and new sensor was applied for simultaneous determination of Pb(II) and Cd(II) ions in water samples with the ...Vesna Antunović, Marija Ilić, Rada Baošić, Dijana Jelić, Aleksandar Lolić. "Synthesis of MnCo2O4 nanoparticles as modifiers for simultaneous determination of Pb(II) and Cd(II)" in PLOS ONE (2019). https://doi.org/10.1371/journal.pone.0210904
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Mine ventilation system planning using genetic algorithms
The most common problem in contemporary mining practice related to the planning and analysis of ventilation systems is the optimization of partially regulated air distribution in mine ventilation networks. This paper presents a two step optimization procedure for partly regulated air distribution in mine ventilation networks. The first step is the determination of air distribution in all branches using the well known Hardy-Cross method. In the second step the distribution and parameters of air flow regulators with minimum engaged ...coal, lignite, and peat; ventilation systems; coal mining; underground mining; ventilation; mathematical models; design; air flow; optimization; calculation methodsNikola Lilić, Ranka Stanković, Ivan Obradović. "Mine ventilation system planning using genetic algorithms" in 6. international symposium on mine planning and equipment selection, Ostrava (Czech Republic), 3-6 Sep 1997, A.A. Balkema, Rotterdam (Netherlands) (1997)
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Sinteza i strukturna karakterizacija mikroporoznih arsenata i fosfata
Sabina Z. Kovač (2015-09-28)Predmet rada i istraživanja ove doktorske disertacije su sinteza i strukturnekarakteristike novih kristalnih arsenata i fosfata koji sadrže Mg, K, Ca, Mn, Fe, Co, Ni,Cu, Zn, Sr, Ba i druge katjone. U strukturama arsenata i fosfata, AsO4- i PO4-tetraedrinajčešće se vezuju sa tetraedarski ili oktaedarski koordinisanim katjonima prelaznihmetala formirajući otvorene strukture (slojeve ili 3D mreže) sa širokim opsegomrazličitih topologija. U šupljinama ili porama u obliku povezanih ili nepovezanihkanala, tunela, kaveza i međuslojnog prostora mogu se ugraditi različiti vanmrežni joni(obično ...... raspodele elemenata na površini uzorka, jer svaki hemijski element daje karakterističan emisioni spektar rendgenskog zračenja. Merenje talasnih dužina (WD, engl. „wavelength dispersive”) ili energija (ED, engl. „energy dispersive”) emitovanog zračenja omogućava identifikaciju prisutnih elemenata. Za ...
... fosfata Sabina Z. Kovač 4 2. TEORIJSKI DEO 2.1. Hemija arsena i fosfora 2.1.1. Arsen Arsen je element 15. grupe periodnog sistema elemenata zajedno sa azotom, fosforom, antimonom i bizmutom. Relativna atomska masa arsena je 74,921, a atomski broj je 33. Jedini izotop ...
... organskog porekla. Kristalna struktura apatita je veoma prilagodljiva i dozvoljava ulazak skoro polovine elemenata periodnog sistema. Stoga apatiti služe kao „skladišta” sporednih i elemenata u tragovima (Hughes and Rakovan, 2002). Fosfatni minerali lantanoida, monacit, monoklinični CePO4, (Krstanović ...Sabina Z. Kovač. "Sinteza i strukturna karakterizacija mikroporoznih arsenata i fosfata" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2015-09-28)
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Hydrochemical impact of the hydraulic tunnel on groundwater in the complex aquifer system in Pirot, Serbia
Hidrogeohemijski procesi, hidrohemijske promene, karstna izdan, tunel pod pritiskom, multivarijantne statističke analizeMarina Ćuk, Igor Jemcov, Ana Mladenović, Marina Čokorilo Ilić. "Hydrochemical impact of the hydraulic tunnel on groundwater in the complex aquifer system in Pirot, Serbia" in Carbonates and Evaporites, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s13146-020-00563-y
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Correlability of Solar Wind with Seismic Events in the Balkan Peninsula Zone
The Solar Heliospheric Observatory (SOHO) satellite was launched on the 2nd of December 1995 at L1 Lagrange point (1.5×106 km from Earth) with the purpose of gathering data for helioseismology, remote sensing of the solar atmosphere, and solar wind in situ. The satellite was positioned into orbit in early 1996, with data acquisition expected to commence on January 20th. The correlation between increased values of solar wind parameters and earthquakes in the Balkan peninsula zone between 1996 and 2018 ...Filip Arnaut, Dejan Vučković, Ivana Vasiljević, Vesna Cvetkov. "Correlability of Solar Wind with Seismic Events in the Balkan Peninsula Zone" in Geološki anali Balkanskog poluostrva, Beograd : Univerzitet u Beogradu - Rudarsko geološki fakultet (2021). https://doi.org/10.2298/GABP211029008A
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A multi-criteria approach for assessing the potential of renewable energy sources for electricity generation: Case Serbia
When assessing the potential of renewable energy alternatives for electricity generation, it is necessary to implement a multi-perspective approach that includes economic, technical, environmental, and socio-political criteria. For the evaluation of criteria and alternatives, the Fuzzy Analytical Hierarchy Process (FAHP) method is applied. The obtained weights are formed according to the values of energy indicators and expert judgments. The use of a fuzzy numerical value scale for the assessment of expert judgments and energy indicators provides a more sensitive ...... pointed out, the analysis of costs in IRENA’s report was focused on esti- mating the costs of renewables from the perspective of investors, whether they are a state-owned electricity generation utility, an independent power producer, or a community looking to invest in renewables. The analysis excludes the ...
... y steps. Nat Commun 10 (2019), 1077. Buckley, J.J., 1985. Fuzzy hierarchical analysis. Fuzzy Sets and Systems 17 (3), 233–247. Campos-Guzmán, V., García-Cáscales, M.S., Espinosa, N., Urbina, A., 2019. Life cycle analysis with multi-criteria decision making: A review of approaches for the sustainability ...
... 27 January 2021 Accepted 4 February 2021 Available online xxxx Keywords: Electricity generation Renewable energy sources Multi-criteria decision analysis Serbia a b s t r a c t When assessing the potential of renewable energy alternatives for electricity generation, it is necessary to implement a ...Boban Pavlović, Dejan Ivezić, Marija Živković. "A multi-criteria approach for assessing the potential of renewable energy sources for electricity generation: Case Serbia" in Energy Reports, Elsevier BV (2021). https://doi.org/10.1016/j.egyr.2021.02.072
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Using Lexical Resources for Irony and Sarcasm Classification
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) ...... is used more and more in NLP tasks, primarily for advancement of sentiment analysis systems, machine translation, authorship attribution, but also for systems analyzing linguistic structures at different levels – e.g. analysis of sentiment classification results in comments published on newspaper web ...
... Philipp Cimiano, and Roman Klinger. 2014. An impact analysis of features in a classification approach to irony detection in product reviews. In Proc. of the 5th Workshop on Computational Approaches to Subjectivity, Sentiment and Social Media Analysis (WASSA) – 52th ACL. 42–49. [7] John D Campbell and ...
... 2012. Irony and Sarcasm: Corpus Generation and Analysis Using Crowdsourcing. In 8th LREC. 392–398. [14] Aniruddha Ghosh, Guofu Li, Tony Veale, Paolo Rosso, Ekaterina Shutova, John Barnden, and Antonio Reyes. 2015. Semeval-2015 task 11: Sentiment analysis of figurative language in Twitter. In Proc. of ...Miljana Mladenović, Cvetana Krstev, Jelena Mitrović, Ranka Stanković. "Using Lexical Resources for Irony and Sarcasm Classification" in Proceedings of the 8th Balkan Conference in Informatics (BCI '17), New York, NY, USA, : ACM (2017). https://doi.org/
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Дефинисање механичких својстава алтерисаног стенског материјала лабораторијским методама
Вељко М. Рупар (2022)Основни циљ овог рада је да представи методологију одређивања механичких својстава хетерогеног стенског масива који изграђују дацит (Д) и алтерисани дацит (АД), где је уочена је зона постепеног преласка од алтерисаног дацита до дацита. Механичка својства стенског масива у тој зони утврђена су на основу лабораторијских испитивања једноосне и троосне чврстоће на притисак стенског материјала композитних узорака. Композитни узорци су се састојали од дискова стенског материјала, при чему је висина дискова h дефинисала различити процентуални удео појединог стенског материјала, ...дацит, алтерисани дацит, једноосна чврстоћа на притисак, троосна чврстоћа на притисак, композитни узорци, механика стена, стабилност косинаВељко М. Рупар. Дефинисање механичких својстава алтерисаног стенског материјала лабораторијским методама, Београд : [В. Рупар], 2022
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Geothermal potential, chemical characteristic and utilization of groundwater in Serbia
To collect and unify data about all geothermal resources in Serbia, a database was formed. The database allows us to perceive the geothermal resources of Serbia and their potential for utilization. Based on the data available in the geothermal database, the estimated temperatures of reservoirs, heat power, and geothermal energy utilization were calculated. The database contains 293 geothermal records (springs, boreholes) registered at 160 locations, with groundwater temperatures in the range between 20 and 111 °C. The maximum expected ...Geothermal database, Geothermal resources, Geothermal potential, Hydrochemistry, Hierarchical cluster analysis, SerbiaTanja Petrović Pantić, Katarina Atanasković Samolov, Jana Štrbački, Milan Tomić. "Geothermal potential, chemical characteristic and utilization of groundwater in Serbia" in Environmental Earth Sciences, Springer Link (2021). https://doi.org/https://doi.org/10.1007/s12665-021-09985-w
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A new polymorph of Ba(AsO3OH): Synthesis, crystal structure and vibrational spectra
Tamara Đorđević, Ljiljana Karanović (2010)A new monoclinic polymorph of Ba(AsO3OH) was synthesized under hydrothermal conditions. It represents a previously unknown structure type. Its crystal structure was determined from a racemic twin using single-crystal X-ray diffraction data collected at 120 and 293 K [space group P21, a=7.2149(14)/7.2370(2), b=7.7028(15)/7.7133(2), c=21.7385(43)/21.8079(5) Å, β=95.95(3)/96.073(1)1, V=1201.6(4)/1210.51(5) Å3, Z=12]. The crystal structure of P21-Ba(AsO3OH) has a layered character and is built up of four types of regularly alternating layers parallel to (0 0 1). Every AsO3OH tetrahedron is chelating to two Ba atoms and ...Ba(AsO3OH), хидротермална синтеза, структурна анализа монокристала, Раманска спектроскопија, инфрацрвена спектроскопија, водоничне везе, хидрогенарсенати земноалкалних металаTamara Đorđević, Ljiljana Karanović. "A new polymorph of Ba(AsO3OH): Synthesis, crystal structure and vibrational spectra" in Journal of Solid State Chemistry, Elsevier BV (2010). https://doi.org/10.1016/j.jssc.2010.09.027
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Dating of alluvial sediments from borehole at the lower course of the Sava river and indications of the connection between their genesis and climate changes in the Pleistocene
David Mitrinović, Jelena Zarić, Oliver Anđelković, Gyorgy Sipos, Dušan Polomčić, Milan Dimkić (2019)This paper analyses the way in which Pleistocene climate change and glaciations in Dinaric Mountains was reflected in the deposition of alluvial sediments in the Sava river Valley, using a case study of Belgrade Groundwater Source (BGS), the largest and most downstream alluvial water supply source along the Sava river. A stratigraphic analysis of the Quaternary sediments from two boreholes on this site, based on sediment dating, lithological members identification, grain size distribution analysis was performed. Comparison with the ...Pleistocene, Alluvial deposits, Climato-lithostratigraphy, Sava river, Belgrade groundwater source, LuminescenceDavid Mitrinović, Jelena Zarić, Oliver Anđelković, Gyorgy Sipos, Dušan Polomčić, Milan Dimkić. "Dating of alluvial sediments from borehole at the lower course of the Sava river and indications of the connection between their genesis and climate changes in the Pleistocene" in Quaternary International, Elsevier BV (2019). https://doi.org/10.1016/j.quaint.2019.09.028
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Production information system of the Pljevlja coal mine
Božo Kolonja, Ranka Stanković, Filip Vuković . "Production information system of the Pljevlja coal mine" in Mine Planning and Equipment Selection 2000, Routledge (2018). https://doi.org/10.1201/9780203747124-154
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Investigation of nanostructured Ca0.9Er0.1MnO3 obtained by sucrose nitrate procedure
Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić (2023)... structure. The resulting: CapEro,, MnOxy is calcined for 15 minutes in the temperature range from 800% to 1000%. Diffraction thermal analysis (DTA), X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and inductively coupled plasma ICP were ...
... influence of geometry on the determination of the stress intensity factor KI on specimens produced by the selective laser sintering technique.The analysis of the determination of the stress intensity factor includes experimental and numerical tests. For this purpose, two geometries of specimens were ...Tijana B. Vlašković, Bojana Laban, Maja Milošević, Maria Čebela, Vladimir Dodevski, Milena Rosić. "Investigation of nanostructured Ca0.9Er0.1MnO3 obtained by sucrose nitrate procedure" in Program ; and the Book of abstracts The Eleventh Serbian Ceramic Society Conference »Advanced Ceramics and Application« September 18-20, 2023 Serbian Academy of Sciences and Arts, Belgrade, Serbia , Belgrade : Serbian Academy of Sciences and Art Serbia (2023)
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Ocena zaštitne funkcije povlatnih slojeva izvorišta Jasik (Opština Batočina) primenom GLA metode
U cilju utvrđivanja rezervi podzemnih voda i analize uslova zaštite u periodu 2012. i 2013. godine, sprovedena su detaljna hidrogeološka istraživanja na području izvorišta Jasik (opština Batočina). Uspostavljen je sistem monitoringa, čiji je rezultat predstavljao prikupljanje detaljnih hidrogeoloških podataka. Za potrebe analize, izrađen je hidrodinamički model, na osnovu koga je simulirano kretanje podzemnih voda, odnosno, utvrđene zone sanitarne zaštite. Pored navedenog, za potrebe utvrđivanja uslova zaštite podzemnih voda, bilo je neophodno utvrditi podložnost aluvijalne izdani izvorišta Jasik zagađenju. Polazeći ...Rastko Petrović, Igor Jemcov, Dušan Polomčić. "Ocena zaštitne funkcije povlatnih slojeva izvorišta Jasik (Opština Batočina) primenom GLA metode" in Vodoprivreda, Srpsko društvo za navodnjavanje i odvodnjavanje (2014)
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Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector
To strengthen the security of supply of the Serbian gas sector, it is necessary to analyze the impact of planned strategic measures. The analysis involves the identification of the most influential threats to the security of natural gas supply and prioritization of the strategic measures for overcoming the consequences of threats. The proposed methodology is based on Fuzzy Analytic Hierarchy Process. The obtained weights for the identified threats and strategic measures are formed according to experts' judgments. The results ...Sigurnost snabdevanja, Donošenje odluka, Snabdevanje prirodnim gasom, Fazi AHP, Energetski indikatoriBoban Pavlović, Dejan Ivezić, Marija Živković. "Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector" in Energy Policy, Elsevier BV (2020). https://doi.org/10.1016/j.enpol.2020.111936
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Towards the semantic annotation of SR-ELEXIS corpus: Insights into Multiword Expressions and Named Entities
Овај рад представља активности на развоју корпуса ELEXIS-sr, српском додатку вишејезичном анотираном корпусу ELEXIS-а, који се састоји од семантичких анотација и репозиторија значења речи. ELEXIS је паралелни вишејезични анотирани корпус на десет европских језика, који може да се користи као вишејезички репер за евалуацију европских језика са мање и средње развијеним ресурсима. Фокус овог рада је на вишечланим изразима и именованим ентитетима, њиховом препознавању у скупу реченица ELEXIS-sr и поређењу са анотацијама на другим језицима. Разматрају се први кораци ...Cvetana Krstev, Ranka Stanković, Aleksandra Marković, Teodora Mihajlov. "Towards the semantic annotation of SR-ELEXIS corpus: Insights into Multiword Expressions and Named Entities" in Proceedings of the Joint Workshop on Multiword Expressions and Universal Dependencies (MWE-UD) @ LREC-COLING 2024, Turin, May 25, 2024, ELRA and ICCL (2024)
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A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers
Effectiveness evaluation is one of the basic components of engineering asset management and maintenance engineering in general. Effectiveness is an overall concept representing a measurement of quality of service level for the analyzed engineering system. This concept contains a series of partial indicators relating to time in operation and time for maintenance activities, as well as functional properties of the system. This article describes the analysis and structuring of partial indicators, as well as the development of a model ...Miloš Tanasijević, Predrag Jovančić, Dejan Ivezić, Uglješa Bugarić, Radiša Đurić. "A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers" in International Journal of Industrial Engineering: Theory, Applications and Practice (2019)
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‘Blue-’ and ‘Brown-speckled’ pottery from Qalhât, the Sultanate of Oman (13–16th centuries): Comparison with traditional Omani 19–20 century productions
Representative ‘Blue speckled’ (13–16th centuries) and ‘Brown speckled’ (13–21st century) wares recovered from the excavations in Qalhât or collected around Bahlâ city (Sultanate of Oman) were characterized by XRPD, SEM-EDS, Raman/optical microspectroscopy, and thermal expansion. Minerals present in the body (quartz, augite and albite as major phases, calcite, dolomite, rutile, anatase, phosphate, hematite and magnetite as minor phases) were identified by XRPD and/or Raman spectroscopy. SEM-EDXS microanalysis was performed on the glazes in order to compare their composition, especially ...Liliana Gianni, Hélène Renel, Aleksandar Kremenović, Philippe Colomban. "‘Blue-’ and ‘Brown-speckled’ pottery from Qalhât, the Sultanate of Oman (13–16th centuries): Comparison with traditional Omani 19–20 century productions" in Boletín de la Sociedad Española de Cerámica y Vidrio, Elsevier BV (2020). https://doi.org/10.1016/j.bsecv.2020.06.005
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Alpine thermal events in the central Serbo-Macedonian Massif (southeastern Serbia)
Milorad D. Antić, Alexandre Kounov, Branislav Trivić, Andreas Wetzel, Irena Peytcheva, Albrecht von Quadt (2015)Milorad D. Antić, Alexandre Kounov, Branislav Trivić, Andreas Wetzel, Irena Peytcheva, Albrecht von Quadt. "Alpine thermal events in the central Serbo-Macedonian Massif (southeastern Serbia)" in International Journal of Earth Sciences, Springer Science and Business Media LLC (2015). https://doi.org/10.1007/s00531-015-1266-z