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Упит dcterms_subject_txt:DFT analysis

747 items

  • Analiza pouzdanosti dozera angažovanih na površinskim kopovima RB Kolubara

    Filip Miletić, Dragan Milčić, Miloš Tanasijević, Miloš Milovančević (2021)
    U radu je izvršena uporedna analiza pouzdanosti transportnih sistema dozera koji rade na površinskim kopovima Rudarskog basena Kolubara. Period za koji je vršena analiza je prvih deset godina eksploatacije. Efikasnost tehnološkog procesa na otkopavanju korisne mineralne sirovine i otkrivke u velikoj meri zavisi od rada dozera. Iskorišćene su matematičke metode za aproksimaciju i identifikaciju zabeleženih vremena u radu, kako bi se dobili analitički pokazatelji pouzdanosti. Na ovaj način se bitno podiže kvalitet upravljanja procesom eksploatacije i održavanja mašina na ...
    dozeri, pouzdanost, kolubarski ugljeni basen
    ... pouzdanost, kolubarski ugljeni basen Abstract: The paper presents a comparative reliability analysis of the dozers transport systems which working on the open pit mines of the Kolubara Mining Basin. Analysis period is first ten years of exploitation. Efficiency of process on excavation of mineral raw ...
    ... arski, sa parametrom oblika i parametrom razmere η. [7] Parametri raspodele mogu se odrediti analitički, metodom najmanjih kvadrata (Regression analysis) [8] i grafički. Analitički postupak daje nešto tačnije rezultate. Primenom grafičkih metoda može se oceniti tačnost razvijenog modela zakona raspodele ...
    ... mašinskih delova i sistema u okruženju Microsoft Excel, Infoteh–Jahorina Vol. 10, Ref. C-8, p. 273-277, Mart 2011; [8] Ashish S., Muni S. Regression analysis - Theory, Methods, and Applications, Springer-Verlag New York, 1990.; [9] Milčić D. Pouzdanost mašinskih sistema, Univerzitet u Nišu, Mašinski fakultet ...

  • Surface functional groups and degree of carbonization of selected chars from different processes and feedstock

    Marija Ilić, Franz-Hubert Haegel, Aleksandar Lolić, Zoran Nedić, Tomislav Tosti, Ivana Sredović Ignjatović, Andreas Linden, Nicolai D. Jablonowski, Heinrich Hartmann (2022)
    The knowledge ofthe structural and chemical properties of biochars is decisive for their application as technical products. For this reason, methods for the characterization of biochars that are generally applicable and allow quality control are highly desired. Several methods that have shown potential in other studies were used to investigate two activated carbons and seven biochars from different processes and feedstock. The chars were chosen to cover a wide range of chemical composition and structural properties as a hardness ...
    Biougalj, različiti procesi dobijanja, različite sirovine, površinski aktivne grupe, x-ray, FT-IR,XPS
    ... of K2p. https://doi.org/10.1371/journal.pone.0277365.t006 corresponds to the abundance found by chemical analysis and by XRD. The deviation of the O/C ratio from XPS and element analysis (Fig 2) was largest for the activated carbons and PW?700g. The lower O/C ratio for AC2 obtained by XPS can ...
    ... 100%) and the determination of ash forming elements. This complete analysis is the base for understanding the properties of the chars. In special cases, as for the presence of phosphoric acid in AC2, additional chemical analysis might be necessary to elucidate the true composition. X-ray diff ...
    ... spectroscopic methods was found to be suitable for the quality control of all types of chars. The most valuable results were obtained by chemical analysis that, however, required the complete determination of the main elements, including that of oxygen, and of inorganic components for adequate results ...

  • The correlation of Upper Miocene lithostratigraphic units of the southern part of the Pannonian basin

    Filip Anđelković, Dejan Radivojević (2019)
    gornji miocen, litostratigrafske jedinice, formacije, Panonski basen
    ... basin is a classical back-arc basin formed during Miocene times. The rifting took place along asymmetric simple shear extensional mechanism. The analysis of syn- kinematic reflectors demonstrates that normal faulting migrates in time and space and took place on a wide Miocene time interval (roughly ...
    ... this paper is the southern part of the Pannonian Basin, and more specifically, the parts which have been well-documented and where the formational analysis has been carried out. The concrete areas are: North Banat (Serbia), southeastern parts of Hungary (Great Hungarian Plain), as well as some parts ...
    ... Magyar, I., Horváth, F., Cloething, S., (2016). The link between tectonics and sedimentation in back-arc basins: New genetic constraints from the analysis of the Pannonian Basin. Tectonics. 35, pp.1526-1559 2. Balázs, A., Burov, E., Mațenco, L., Vogt, K., Francois, T., Cloething, S., (2017). Symmetry ...

  • Hydrochemical features and their controlling factors in the Kucaj-Beljanica Massif, Serbia

    Fen Huang, Ljiljana Vasic, Xia Wu, Jianhua Cao, Saša Milanovic (2019)
    Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • Analiza sistema odvodnjavanja površinskog kopa Drmno od podzemnih voda sa severnim savršenim ekranom

    Tomislav Šubaranović, Dušan Polomčić, Vladimir Pavlović (2019)
    Izrada nesavršenog ekrana do drugog sloja uglja na površinskom kopu Drmno, pored zadržavanja postojećih standardnih metoda odvodnjavanja od podzemnih voda linijama bunara, predviđena je poslednje decenije u celokupnoj rudarskoj projektnoj dokumentaciji. Iz objektivnih i subjektivnih razloga njegova realizacija nije ostvarena do danas. U međuvremenu je, uz dodatna geološka istraživanja i promenu dinamike i parametara sistema površinske eksploatacije, došlo do određenih značajnih prostornih promena geoloških i rudarskih uslova u eksploatacionom polju. Ovo je omogućilo preliminarno inoviranje pristupa procesu i konceptu ...
    podzemne vode, odvodnjavanje, bunari, ekran, dinamika, troškovi

  • Complex geophysical survey on solving the problem of water loss in the karst terrain reservoir

    Branislav Sretković, Dejan Vučković (2023)
    Geophysical surveys in karst terrain are always a specific challenge. Each of them requires a careful consideration of the problem, specific conditions on the ground, the selection of adequate methods applicable in that specific and unique karst area. But they should have one thing in common: a complex approach and looking at the problem from wider to narrower, with a gradual narrowing of the investigation area, increasing the spatial precision and resolution of the obtained data. On the example of ...

  • Analiza nosivosti vertikalno opterećenog šipa za potrebe izgradnje petlje „Merošina 1“ na autoputu E-80 deonica: Niš – Merošina

    Dragoslav Rakić, Nikola Božović, Miloš Stevanović, Milan Bogdanović (2023)
    U Srbiji je počela izgradnja autoputa E-80 koji će predstavljati saobraćajno čvorište zapadnog Balkana i biće deo glavne regionalne transportne mreže jugoistočne Evrope. Njegova ukupna dužina kroz Srbiju iznosi 77 km, a prva deonica u dužini od 5.5 km je završena i puštena u saobraćaj krajem jula 2023. god. To je prva od četiri deonice Sektora 1 čija je dužina 32.65 km. U sklopu petlje „Merošina 1“ izgrađen je nadvožnjak koji je oslonjen na devet stubnih mesta na međusobnom ...
    petlja Merošina 1, šip, probno opterećenje šipa, projektni pristup, granična stanja

  • Analiza primene višekriterijumskih metoda u optimizaciji izbora hidruličnih bagera na površinskim kopovima uglja

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Filip Miletić, Ivan Janković (2019)
    Hidraulični bageri primenjuju se u različitim oblastima privrede a najzastupljeniji su u građevinarstvu i rudarstvu. Na površinskim kopovima sa kontinualnim sistemima, klasifikuju kao pomoćna mehanizacija a na površinskim kopovima sa diskontinualnim sistemima, kao osnovna mehanizacija. Kako je u oba slučaja njihova primena neizostavna, važno je izvršiti adekvatnu analizu postojećih podataka, u cilju optimizacije izbora tipa hidrauličnog bagera u odnosu na uslove rada datog površinskog kopa. U radu su opisane različite višekriterijumske metode koje su korišćene za analizu hidrauličnih bagera. ...
    višekriterijumske metode, površinski kop uglja, pomoćna mehanizacija, hidraulični bager
    ... adequate analysis of the existing data in order to optimize the choice of the type of hydraulic excavator in relation to the working conditions of a particular open- cast mine. This paper aims to demonstrate the potential of multi-criteria optimization methods that are used in the analysis of hydraulic ...
    ... 5,5 8,4 8,2 Udobnost upravljanja 7,1 9,6 8,5 4. VIŠEKRITERIJUMSKE METODE Višekriterijumska analiza odlučivanja (Multi Criteria Decision Analysis - MCDA) je jedna od naj- značajnijih oblasti operacionih istraživanja koja je veo- ma brzo napredovala u poslednjih 20 godina [7]. Vi- šekriterijumsko ...
    ... Evoluti- onary Algorithms. Procedia Computer Science, 55, pp. 308–317, DOI:10.1016/j.procs.2015.07.054, 2015. [17] Tsaur R. C, Decision risk analysis for an interval TO- PSIS method. Applied Mathematics and Compu- tation 218(8), pp. 4295-4304, doi:10.1016/j.amc.- 2011.10.001, 2011. [18] Hudej ...

  • Towards Automatic Definition Extraction for Serbian

    Ranka Stanković, Cvetana Krstev, Rada Stijović, Mirjana Gočanin, Mihailo Škorić (2021)
    U radu su prikazani preliminarni rezultati automatske ekstrakcije kandidata za definicije rečnika iz nestrukturiranih tekstova na srpskom jeziku u cilju ubrzanja razvoja rečnika. Definicije u rečniku Srpske akademije nauka i umetnosti (SANU) korišćene su za modelovanje različitih tipova definicija (opisnih, gramatičkih, referentnih i sinonimskih) koje imaju različite sintaksičke i leksičke karakteristike. Korpus istraživanja sastoji se od 61.213 definicija imenica, koje su analizirane korišćenjem morfoloških e-rečnika i lokalnih gramatika implementiranih kao pretvarači konačnih stanja u paketu za obradu korpusa otvorenog ...
    ... research, particularly (Barnbrook 2002), analysis of definitions in existing dictionaries and previous research into Serbian (Krstev et al. 2015). 3 Analysis and Recognition of Definitions in the SASA Dictionary The first step in our research was a thorough analysis of various lexical and syntactic features ...
    ... (57%) 24347 (83%) Table 1: The analysis of recognized definitions from the SASA dictionary; the defined word is given in small caps, connected entries are given in bold, while trigger words enabling the connection are given in italic. 4 Corpus Analysis 4.1 Creating a Textbook Corpus For ...
    ... processing suite Unitex. The 21 models developed up to the present moment cover 57% of dictionary definitions, 83% of which were fully recognized. The analysis has shown that many definitions have a structure that can be modelled, as evidenced by the statistics of definitions grouped by type. These models ...

  • Termička zrelost organske supstance i naftno-matični potencijal istočne Hercegovine

    Nikoleta Aleksić (2021)
    Cilj istraživanja, obrade i interpretacije rezultata prikazanih u disertaciji je utvrđivanje termičke zrelosti organske supstance i naftno-matičnog potencijala sedimentnih stena na području istočne Hercegovine, primenom metoda pirolize Rock-Eval, organo-petrografskog proučavanja organske supstance u normalnoj svetlosti i fluorescenciji, koja je pored kvalitativne analize uključila posebno i refleksiju vitrinita. Osim toga, na osnovu organsko-geohemijskih analiza sagledane su karakteristike i poreklo ekstrahovanog bitumena metodom gasne hromatografije - masene spektrometrije, pri čemu su izvršene analize biomarkera kao geohemijskih indikatora. Tokom rada na doktorskoj ...
    organska supstanca, termička zrelost, matične stene, naftni potencijal, refleksija vitrinita, piroliza Rock-Eval, biomarkeri, Karbonatna platforma, istočna Hercegovina

  • Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements

    Filip Miletić, Predrag D. Jovančić, Milos Milovančević, Dragan Ignjatović (2020)
    The capacity of the rotor excavator depends largely on the operation of the subsystem for digging. There is a great contribution to the correct and sharp teeth when the capacity is the highest. In the function of time, the teeth become clogged due to abrasive wear, or changes in their geometric shape. To analyze the bucket wheel drive in depend on wear of the cutting elements in this study adaptive neuro fuzzy inference system (ANFIS) approach was implemented. ANFIS ...
    Pogon rotornog točka, habanje, rezni elementi, ANFIS

  • 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 ...
    Ceria, Yttrium, Solid solution, Mechanosynthesis, Oxygen vacancy, Nanocrystalline material

  • Geochemical evaluation of dolostone deposits in Montenegro: Implications for potential industrial applications

    Darko Bozovic, Vladimir Simic, Dragan Radulovic, Slobodan Radusinovic, Vesna Matovic, Anja Terzic (2024)
    This study presents a unique model for assessing the dependability of continuous parts of combined systems in open-pit mining through the application of fuzzy logic. Continuous sub-systems as part of the combined system of coal exploitation in surface mines have the basic function of ensuring safe operation, high capacity with high reliability, and low costs. These subsystems are usually part of the thermal power plant’s coal supply system and ensure stable fuel supply. The model integrates various independent partial ...
    примарне сировине, минералогија, физичко-механичка својства, технолошка својства, наука о материјалима

  • Epidotizacija sanidina u kvarclatitima Grota

    Danica Srećković-Batoćanin, Suzana Erić, Nikola Novičić, Nikola Pašajlić, Natalija Batoćanin (2023)
    Propilitska alteracija je veoma česta u gornjokredno-tercijarnim vulkanitima Srbije. Kvarclatiti Grota, otkriveni na dubini od oko 550 m u jednoj od istražnih bušotina su holokristalaste porfirske strukture sa fenokristalima sanidina dimenzija i do 1,5 x 2 cm. Optičkim ispitivanjima su u kvarclatitu potvrdjeni i elementi sitaste, pojkilitske i glomeroporfirske strukture. Kao fenokristali prisutni su sanidin, plagioklas, kvarc, biotit i amfiboli. Sekundarni minerali su hlorit, epidot, coisit, Fe-hidroksidi, redak kalcit i ilit. U fenokristalima sanidina se zapažaju „lepeze“ izduženih kristala ...
    Grot, kvarclatiti, sanidin, epidot

  • Definition of Circulation Conditions and Groundwater Genesis of the Complex Krupaja Hydrogeological Karst System (Eastern Serbia)

    Ljiljana Vasić, Saša Milanović, Tina Dašić (2023)
    Management, Monitoring, Policy and Law,Renewable Energy, Sustainability and the Environment, Geography, Planning and Development, Building and Construction
    ... the way to completely scientific research and research related to solving a specific engineering / geological problem or hydrotechnical problem. Analysis of the geometry of the main karst conduits in the saturated zone, as well as their connection to underground morphological objects located above ...
    ... channels within a karst system [4-7]. An important tool for defining , the velocity of groundwater circulation and mean residence time is isotopic analysis, which is increasingly used, and, in correlation to field research, has the potential to contribute significantly to defining, the genesis of g ...
    ... ArcGIS program was used, along; with some additional software [7]. Linked layers and an associated base were used to create a basis for further analysis of karst aquifers through different model components. By defining, the main directions and orientation of karst conduits (followed by a possible ...

  • Razvoj ARCGIS geobaze površinskog kopa korišćenjem UML CASE alata

    Aleksandra Tomašević, Ljiljana Kolonja, Ivan Obradović, Ranka Stanković, Olivera Kitanović (2012)
    ... monitoring and managing work at open pits. It enables not only visualization, but also analysis of stored data. Data registered in this database are the following: data on geological research, physical-chemical analysis of ore samples, infrastructural objects, natural objects, work environment (pit, levels ...
    ... borehole different analyses are performed (petrographic-mineralogical, physical- mechanical, qualitative, which encompasses technical, elementary analysis, ash analysis and ash fusibility), and lithologic and stratigraphic characteristics are established. Results of this research are modeled by classes: Analiza ...
    ... mine production, and pertain to an important segment that demands visual representation. More precisely, the paper tackles exploration works, sample analysis, infrastructure within the mine and in its environment, excavating and loading equipment, etc. The physical implementation of the OpmGIS geodatabase ...

  • Structural characterization of traditional pottery produced from local clay, Rujište (Ražanj, Central Serbia), in an effort to preserve its geoheritage

    Maja Milošević, Biljana Đorđević, Alena Zdravković (2021)
    ... preservation of this type of intangible cultural heritage, inscribed in the National register of ICH and as geoheritage in Serbia as well. The analysis of the phase, mineral composition and structure of the clay body was performed by optical microscopy on cross-sections perpendicular to the vessel ...
    ... which is intimately mixed with clay of the illite type with a very smaller amount of detrital quartz and feldspar (Krstić et al., 1980). In the analysis of the thin sections made of the sample, the basic mass is observed, which represents a sintered fine-grained aggregate and binds large, often ...
    ... hydroxides are mostly present in the form of solid spheres sometimes of regular shape. The main focus of this investigation was the mineralogical analysis of the clay body used in the manufacture of traditional pottery, bread-baking pan called crepulja, prepared with raw local clays from Ražanj area ...

  • A Model for Determining the Dependability of Continuous Subsystems in Coal Mines Using the Fuzzy Logic Approach

    Nikola Stanić, Miljan Gomilanović, Petar Marković, Daniel Krzanović, Aleksandar Doderović, Saša Stepanović (2024)
    This study presents a unique model for assessing the dependability of continuous parts of combined systems in open-pit mining through the application of fuzzy logic. Continuous sub-systems as part of the combined system of coal exploitation in surface mines have the basic function of ensuring safe operation, high capacity with high reliability, and low costs. These subsystems are usually part of the thermal power plant’s coal supply system and ensure stable fuel supply. The model integrates various independent partial ...
    fuzzy logic, max-min composition, continuous part of combined system (CCS), open pit, mining, dependability

  • Rule-based Automatic Multi-word Term Extraction and Lemmatization

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Biljana Lazić, Aleksandra Trtovac (2016)
    In this paper we present a rule-based method for multi-word term extraction that relies on extensive lexical resources in the form of electronic dictionaries and finite-state transducers for modelling various syntactic structures of multi-word terms. The same technology is used for lemmatization of extracted multi-word terms, which is unavoidable for highly inflected languages in order to pass extracted data to evaluators and subsequently to terminological e-dictionaries and databases. The approach is illustrated on a corpus of Serbian texts from ...
    term extraction, terminology, multi-word units, lemmatization, finite-state transducers
    ... place with very little human intervention, starting from the tokenization and lexical analysis of a raw text up to production of dictionary entries. The system relies Unitex routines for text analysis and FST application, while one of the many functionalities of LeXimir is used to produce ...
    ... entity names (organization names and similar named entities found in a corpus of legislative acts) by using rules generated on the basis of corpora analysis. For tackling the problem of MWT extraction and lemmatization from Serbian texts we have chosen a rule-based approach, which relies on a system ...
    ... development. Unitex E-dictionaries Rule based term extraction and lemmatization Corpora Domain specific 1. Tokenization and lexical analysis Local grammars 5. DELAC dictionary production 2. Rule based MWU term extraction and normalization 3. Rule based lemma correction and ...

  • Determining the Groundwater Balance and Radius of Influence Using Hydrodynamic Modeling: the Case Study of the Groundwater Source “Šumice” (Kikinda, Serbia)

    Dušan Polomčić, Dragoljub Bajić, Jelena Zarić (2015)
    A groundwater flow model was developed to simulate groundwater extraction from the public water supply source of the City of Kikinda. The hydrodynamic model includes the municipal groundwater source of Kikinda (Šumice and the Jezero Well), but also an extended area where there are groundwater sources that provide water supply to three factories: (MSK, TM and LŽT - Kikinda). Hydrodynamic modeling, based on the numerical method of finite differences will show the groundwater balance of the sources in the ...
    Water supply, Aquifer, Flow, Groundwater regime, Numerical modeling, Particle tracking
    ... existing sources that have been in service for years, but also when it comes to opening new sources. The best research approach includes hydrodynamic analysis in the early stages of planning and sound monitoring in all stages. Many authors have recently focused on this subject from different perspectives: ...
    ... widest sanitary protection zone [13]. Particle tracking can be used for various purposes. The backward particle tracking method with an uncertainty analysis of porosity, applying a Monte Carlo approach, with Geographic Information System (GIS) support, is a useful tool for delineating groundwater ...
    ... the influence of any hydraulic contact with sandy water-bearing strata that overlie the tapped horizon is avoided, because of both insufficient analysis andartificially-created groundwater renewal difficulties, which certainly affect groundwater source performance. The layer contours were geometrized ...