Претрага
363 items
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Хидрогеохемијске карактеристике и квалитет вода слива Требишњице, Република Српска, Босна и Херцеговина
Dragoslav R. Banjak (2016-08-25)Упркос неповољном временском и просторном распореду, воде су најзначајнијиприродни ресурс Источне Херцеговине. Ова чињеница довела је до реализацијепројекта „Вишенамјенског хидросистема Требишњица“, којим је, премаМилановићу (2006), до сада обухваћено: седам хидроелектрана, шестакумулација, шест брана, шест тунела укупне дужине 59,7 km, неколикоприступних тунела, 62,5 km бетонског канала кроз Попово поље, канал крозДабарско (6750 m) и Фатничко поље (2770 m) и систем тунел-канал или цјевоводпрема Дубравама.У почетку са доминантним енергетским предзнаком, концепција јетрансформисана у интегрално рјешење вишенамјенског коришћења и заштитевода и животне ...хидрогеохемијски процеси, мултиваријантна статистичкаанализа, инверзно геохемијско моделовање, квалитет воде, употребиљивост водеза наводњавање, слив ТребишњицеDragoslav R. Banjak. "Хидрогеохемијске карактеристике и квалитет вода слива Требишњице, Република Српска, Босна и Херцеговина" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2016-08-25)
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Synthesis and characterization of high-pressure and high-temperature sphene (CaTiSiO5)
Jelena Pantić, Vladimir Urbanovich, Vesna Poharc-Logar, Bojan Jokić, Marija Stojmenović, Aleksandar Kremenović, Branko Matović (2014)Sphene (CaTiSiO5), a calcium titanosilicate ceramic has been prepared from a powder mixture of CaCO3, TiO2 and SiO2 using vibro-milling for homogenization and activation of precursors. During the highpressure and high-temperature synthesis (HPS) process at 4 GPa and 1,200 °C, sphene undergoes into phase transition, from room-temperature phase P21/a to high-temperature phase A2/a. Evidence of that structural phase transition is given in this paper using infrared, Raman spectroscopy and X-ray powder diffraction. Rietveld refinement was employed to get the ...Jelena Pantić, Vladimir Urbanovich, Vesna Poharc-Logar, Bojan Jokić, Marija Stojmenović, Aleksandar Kremenović, Branko Matović. "Synthesis and characterization of high-pressure and high-temperature sphene (CaTiSiO5)" in Physics and Chemistry of Minerals, Springer Science and Business Media LLC (2014). https://doi.org/10.1007/s00269-014-0693-x
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Mineralogical analysis of a clay body from Zlakusa, Serbia, used in the manufacture of traditional pottery
... Abdelmalek et al, ). The XRPD traces of the oriented clay fractions of the investigated samples are presented in . The transformation of kaolinite into meta- kaolin is observed with the disappearance of the reflection at 12.3%20 (7.1 A) after heating at 500% (Bergaya & Lagaly, ; Abdelmalek et al., ). ...Maja Milošević, Biljana Đorđević, Mihovil Logar. "Mineralogical analysis of a clay body from Zlakusa, Serbia, used in the manufacture of traditional pottery" in Clay Minerals (2020). https://doi.org/10.1180/clm.2020.20
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Indexing of textual databases based on lexical resources: A case study for Serbian
In this paper we describe an approach to improvement of information retrieval results for large textual databases by pre-indexing documents using bag-of-words and Named Entity Recognition. The approach was applied on a database of geological projects financed by the Republic of Serbia in the last half century. Each document within this database is described by metadata, consisting of several fields such as title, domain, keywords, abstract, geographical location and the like. A bag of words was produced from these ...Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović. "Indexing of textual databases based on lexical resources: A case study for Serbian" in Semantic Keyword-based Search on Structured Data Sources : First COST Action IC1302 International KEYSTONE Conference, IKC 2015, Coimbra, Portugal, September 8-9, 2015. Revised Selected Papers, Springer (2015). https://doi.org/10.1007/978-3-319-27932-9_15
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Effectiveness Analysis of Different Bucket-wheel Excavators
Coal production in open-pit lignite mines in the Republic of Serbia is performed with continuous work systems. In addition to coal production, the same systems are used for the exploitation of large quantities of overburden. According to the reliability concept, continuous systems are in linear connection. If the failure occurs in one part of the system, that will produce a downtime of the entire system. The initial and most important factor of continuous systems is the bucket-wheel excavator. It ...... selecting optimal equipment for the blasting process [9, 10]. The AHP method has proven to be a quality tool for the analysis of the quality factors in metal processing [11]. The selecting of the optimal block size for the needs of the coal deposit modeling process and mine planning can be done with the ...Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić. "Effectiveness Analysis of Different Bucket-wheel Excavators" in 8th International Conference Mining and Environmental Protection, Sokobanja, 22-25 September 2021, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2021)
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The oil industry and climate changes
Dejan Radivojević (2020)Uprkos tome što je problem klimatskih promena poznat dugi niz godina i dalje veliki broj ljudi poistovećuje pojam vremenskih prilika sa klimom ne uzimajući u obzir različitu dužinu njihovog trajanja. U medijima se vrlo često mogu naći katastrofična predviđanja vezana za zagrevanje naše planete usled neodgovornog ponašanja čoveka. Sa druge strane geolozi znaju da je tokom geološke prošlosti naše planete bilo mnogo toplijih intervala od današnjih kao i da ti intervali nisu neminovno rezultovali masovnim izumiranjem živog sveta već su ...Dejan Radivojević. "The oil industry and climate changes" in Tehnika – rudarstvo, geologija i metalurgija, Savez inženjera i tehničara Srbije, Beograd (2020). https://doi.org/10.5937/tehnika2001031R
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Hydrogeochemical distribution of Ca and Mg in groundwater in Serbia
... groundwater and in the environment in general, and are also essential to the human body (Jovic & Jovanovic,2004). Ca is the most abundant alkaline earth metal in the Earth's crust and the main ingredient of many minerals and rocks. The most common Ca-rich minerals are: calcite, aragonite, dolomite, gypsum ...Petar Papić, Jovana Milosavljević, Marina Ćuk, Rastko Petrović . "Hydrogeochemical distribution of Ca and Mg in groundwater in Serbia" in Groundwater: Occurrence and Significance for Human Health, CRC Press, Balkema - Taylor & Francis Group (2014)
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Mineral and Thermal Waters of Serbia: Multivariate Statistical Approach to Hydrochemical Characterization
... Based on the analyzed water samples we can conclude that the elevated α- and β-activities were found mainly in waters originating from magmatic and meta- morphic rocks. Natural radioactivity was mainly due to the high content of 40K and naturally occurring radionuclides of the 238U and 232Th series ...Maja Todorović, Jana Štrbački, Marina Ćuk, Jakov Andrijašević, Jovana Šišović, Petar Papić . "Mineral and Thermal Waters of Serbia: Multivariate Statistical Approach to Hydrochemical Characterization" in Mineral and Thermal Waters of Southeastern Europe, Springer International Publishing (2016). https://doi.org/10.1007/978-3-319-25379-4
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A Simple Flow Injection System for Amperometric Detection of Ascorbic Acid Using Carbon Paste/Copper Schiff Base Composite Electrode
Mihajlo Kulizić, Milan Stanković, Marija Rašić, Aleksandar Mijatović, Rada Baošić, Aleksandar Lolić (2023)askorbinska kiselina, elektroda modifikovane ugljenične paste, analiza protočne injekcije, dijetetski suplementi, amperometrija... as antifungal, antibacterial, antiviral, antipyretic but they also show good catalytic activity in various reactions.*"" The use of transition metal complexes, as mediators, can significantly decrease the overpotential and increase the sensitivity and selectivity of electrochemical sensors. ...Mihajlo Kulizić, Milan Stanković, Marija Rašić, Aleksandar Mijatović, Rada Baošić, Aleksandar Lolić. "A Simple Flow Injection System for Amperometric Detection of Ascorbic Acid Using Carbon Paste/Copper Schiff Base Composite Electrode" in ChemistrySelect, Wiley (2023). https://doi.org/10.1002/slct.202304631
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Vodosnabdevanje podzemnim vodama u Srbiji-stanje i perspektive
Dušan Polomčić, Zoran Stevanović, Petar Dokmanović, Petar Papić, Vesna Ristić-Vakanjac, Bojan Hajdin, Saša Milanović, Dragoljub Bajić (2011)Dušan Polomčić, Zoran Stevanović, Petar Dokmanović, Petar Papić, Vesna Ristić-Vakanjac, Bojan Hajdin, Saša Milanović, Dragoljub Bajić. "Vodosnabdevanje podzemnim vodama u Srbiji-stanje i perspektive" in Naših 40 godina, Beograd : Rudarsko-geološki fakultet (2011): 49-77
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Proračun osnovnih mehanizama na rotornom bageru ShRs 1300 na PK Polje E
Luka Nikolić (2024)Površinska eksoloatacija ležišta mineralnih sirovina, a posebno uglja (lignita) vrši se primenom različitih rudarskih mašina. U zavisnosti od tipa ležišta, rudarsko-geoloških uslova, ekonomske analize i sl. koriste se sistemi sa kontinualnim ili diskontinualnim načinom rada.Kod kontinualnih sistema, primenjuju se kompleksne rudarske mašine kod kojih se proces odvija neprekidno odnosno bez ciklusa utovara, transporta i odlaganja i najčešće rade u sve tri smene. Rotorni bageri i bageri vedričari, transporteri sa gumenom trakom, odlagači ili deponijske mašine čine tkz BTO ili ...... Geografski položaj PK polje E RB „Kolubara“ se sastoji od više radnih Jedinica i to su „Kolubara-Površinski kopovi“, „Kolubara-Prerada,“ Kolubara Metal“, „Kolubara Projekt“, koje se osim proizvodnje i prerade uglja bave i proizvodnjom rudarske opreme i projektovanjem u oblasti rudarstva ı građevinarsta ...
... obuhvata pored radova koji su predviđeni servisom i sve radove, koji su navedeni u nalogu za popravku. Njega izvode investicione grupe iz „Kolubare-Metal“ potpomognute ekipama iz radionica pri površinskom kopu. Slika 4 Kugle i Staze Slika 3 Rotorni bager SRs 1300 za vreme remonta 3. OPŠTE O ROTORNIM ...Luka Nikolić. Proračun osnovnih mehanizama na rotornom bageru ShRs 1300 na PK Polje E, 2024
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Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites
Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković (2023)To investigate the effect of synthesis procedure and sintering temperature on the functional properties of perovskite/spinel ceramics, BaTiO3/CoFe2O4 composites were prepared by thermal decomposition, coprecipitation, and microemulsion method, and sintered at 1150°C and 1300°C. The phase composition and morphology of as-prepared powders as well as sintered ceramics were thoroughly examined by X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM) coupled with electron dispersive spectroscopy (EDS). The dielectric and ferroelectric measurements were performed in detail. Generally, the ...Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković. "Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites" in Science of Sintering (2023). https://doi.org/10.2298/SOS220512013S
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Mechanosynthesis and structural characterization of nanocrystalline Ce1–Y O2– (x=0.1–0.35) solid solutions
Martin Fabián, Bratislav Antić, Vladimír Girman, Milica Vučinić-Vasić, Aleksandar Kremenović, Shigeru Suzuki, Horst Hahn, Vladimír Šepelák (2015)A series of nanostructuredfluorite-type Ce1–xYxO2–δ (0rxr0.35) solid solutions, prepared via highenergy milling of the CeO2/Y2O3mixtures, are investigated by XRD, HR-TEM, EDS and Raman spectroscopy. For thefirst time, complementary information on both the long-range and short-range structural features of mechanosynthesized Ce1–xYxO2–δ, obtained by Rietveld analysis of XRD data and Raman spectroscopy, is provided. The lattice parameters of the as-prepared solid solutions decrease with increasing yttrium content. Rietveld refinements of the XRD data reveal increase in microstrains in the host ceria ...Martin Fabián, Bratislav Antić, Vladimír Girman, Milica Vučinić-Vasić, Aleksandar Kremenović, Shigeru Suzuki, Horst Hahn, Vladimír Šepelák. "Mechanosynthesis and structural characterization of nanocrystalline Ce1–Y O2– (x=0.1–0.35) solid solutions" in Journal of Solid State Chemistry, Elsevier BV (2015). https://doi.org/10.1016/j.jssc.2015.06.027
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Integrative GHG Assessment in Oil and Gas Industry
Reducing greenhouse gas emissions is one of the main targets of national strategies in European countries. As a main contributor to emissions, the energy sector is recognized as the most promising to apply measures and actions aimed to decrease GHG emissions. The Oil and Gas industry as a significant contributor to global greenhouse gas emissions is facing a growing need for estimating, mitigating, and reducing the impact of their operations on the atmosphere to stay competitive in a newly ...... ciljem identifikacije glavnih izvora emisija. Pokazano je da je glavni izvor emisija sagorevanje gasa, pri čemu ključni doprinos daje neizgoreli metan. Ključne reči — cencrgetska tranzicija, emisije gasova staklene bašte, industrija, nafta & gas. IINTRODUCTION he global population growth and ...Aleksandar Mirković, Marija Živković, Stevan Đenadić, Darja Lubarda, Chinedu Anyanwa. "Integrative GHG Assessment in Oil and Gas Industry" in Energija, ekonomija, ekologija (2023). https://doi.org/10.46793/EEE23-1.51M
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Keyword Extraction from Parallel Abstracts of Scientific Publications
Slobodan Beliga, Olivera Kitanović, Ranka Stanković, Sanda Martinčić-Ipšić . "Keyword Extraction from Parallel Abstracts of Scientific Publications" in Sematic Keyword-Based Search on Structured Data Sources - Third International KEYSTONE Conference, IKC 2017 Gdańsk, Poland, September 11–12, 2017 Revised Selected Papers and COST Action IC1302 Reports, Springer (2017)
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Ostvarivanje dobiti pri uvođenju sistema agregatnih zamena na osnovnoj rudarskoj mehanizaciji površinskih kopova EPS
Jedan od osnovnih zadataka na površinskim kopovima uglja je ostvarivanje zadovoljavajućeg vremenskog i kapacitetnog iskorišćenja kontinualnih sistema. Da bi se to postiglo, neophodno je izvršiti izmene u postojećoj strategiji održavanja. Preduslov je uvođenje agregatne zamene vitalnih delova na rudarskim mašinama. Benefiti su višestruki. Očekivani rezultati ovakvog pristupa su: smanjenje zastoja i povećanje vremena rada; direktne materijalne uštede; bolja organizacija rada; racionalizaciju radioničkih i magacinskih kapaciteta; povećanje vrednosti mašina. Da bi se uvela agregatna zamena neophodne su investicije za nabavku ...... i mehanizacije računa se na osnovu specifičnog troška angažovanja kompanije koja sprovodi remont. U ovom slučaju je reč o delu preduzeća Kolubara Metal koja je bila angažovana na sprovođenju remontnih aktivnosti na pojedinim bagerima RB Kolubare. U Tabeli 5 prikazani su parametri troškova na sprovođenju ...Predrag Jovančić, Ignjatović Dragan, Đenadić Stevan. "Ostvarivanje dobiti pri uvođenju sistema agregatnih zamena na osnovnoj rudarskoj mehanizaciji površinskih kopova EPS" in X Međunarodna konferencija UGALJ, Zlatibor, Srbija, 13-16. Oktobar 2021., Jugoslovenski komitet za površinsku eksploataciju (2021)
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Mineralogical study of clays from Dobrodo, Serbia, for use in ceramics
... labels. 370 Maja Milošević et al. The samples (10 g) were ground in a HERZOG HSM 100H vibra- tional mill for 30 s to pass through a 160 μm sieve. Metal sample holders were filled with boric acid powder over which the samples were evenly distributed and then pressed (10 s) in a T-40 SPECAC press to form ...Maja Milošević, Predrag Dabić, Sabina Kovač, Lazar Kaluđerović, Mihovil Logar. "Mineralogical study of clays from Dobrodo, Serbia, for use in ceramics" in Clay Minerals, Mineralogical Society (2019). https://doi.org/10.1180/clm.2019.49
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Arsenic in Tap Water of Serbia´s South Pannonian Basin and Arsenic Risk Assessment
Petar Papić, Marina Ćuk, Maja Todorović, Jana Stojković, Bojan Hajdin, Nebojša Atanacković, Dušan Polomčić (2012)Petar Papić, Marina Ćuk, Maja Todorović, Jana Stojković, Bojan Hajdin, Nebojša Atanacković, Dušan Polomčić. "Arsenic in Tap Water of Serbia´s South Pannonian Basin and Arsenic Risk Assessment" in Polish Journal of Environmental Studies (2012)
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From DELA Based Dictionary to Leximirka Lexical Database
Biljana Lazić, Mihailo Škorić (2020)In this paper, we will present an approach in transforming Serbian language Morphological dictionaries from a DELA text format to a lexical database dubbed Leximirka. Considering the benefits of storing data within a database when compared to storing them in textual documents, we will outline some of the functionality that the database has made possible. We will also show how hand-made rules that use category labels lexical entries are marked with can be used to link lexical entries. ...Biljana Lazić, Mihailo Škorić. "From DELA Based Dictionary to Leximirka Lexical Database" in Infotheca, Faculty of Philology, University of Belgrade (2020). https://doi.org/10.18485/infotheca.2019.19.2.4
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Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept
Improvements of Machine Learning-based landslide prediction models can be made by optimizing scale, customizing training samples to provide sets with the best examples, feature selection, etc. Herein, a novel approach, named Cross-Scaling, is proposed that includes the mixing of training and testing set resolutions. Hypothetically, training on a coarser resolution dataset and testing the model on a finer resolution should help the algorithm to better generalize ambiguous examples of landslide classes and yield fewer over/underestimations in the model. This ...... method since they provided accurate results and generalized effectively regardless of the input data distribution or type. Recently, ensemble (multi- or meta-) learning has become more popular in LSA than SVM and other techniques. Random Forest (RF), a relatively new ensemble learning technique, revolutionized ...
... lity. When it replaces the dot product in the linear equation the classification function becomes: The RF is actually an ensemble learning method (meta-classifier) that combines multiple Random Tree (RT) algorithms, which are learning techniques on their own. The RT algorithm has a tree-like structure ...Uroš Đurić, Miloš Marjanović, Zoran Radić, Biljana Abolmasov. " Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept" in Engineering Geology , Elsevier (2019). https://doi.org/10.1016/j.enggeo.2019.05.007