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Упит dcterms_subject_txt:diagnostics of operating coditions,Random Forest

2828 items

  • A Knowledge-Based Approach to Mine Ventilation Planning in Yugoslav Mining Practice

    Nikola Lilić, Ivan Obradović, Ranka Stanković (2002)
    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 ...
    ... analysis of necessary airflow volumes for the ventilation of individual workplace locations, often featuring a very complex geometry. The application of CFD software improves the reliability and quality of the apprehension and verification of air amounts needed for the ventila- tion of workplaces ...
    ... which lead to an unfavorable estimation of the air loss characteristic of the ventilation system state. In addition to that, the value of the airflow loss frequency parameter in the system, which is the ratio of the number of air loss branches and the total number of branches, was 0.28 (5/18). This value ...
    ... the optimization of the ventilation network by means of a genetic algorithm. The variable representing the pressure of the booster fan varies in wide limits of given values from 10 Pa to 600 Pa. The variable related to the location of the fan takes values from a predetermined set of branches where ...

  • Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides

    Lazar Kaluđerović, Zorica Tomić, Rada Đurović-Pejčev, Maja Milošević (2021)
    ... from the environment. The efficiency of the sorption of S-metolachlor by montmorillonite depends on the size of the interlayer space, the type of interchangeable cation, and also on the characteristics of the montmorillonite surface. Disclosure of Interest: None Declared Keywords: ...
    ... CHARACTERIZATION OF NATURAL CLAY FROM BOGOVINA (SERBIA) AND POSSIBLE UTILIZATION IN SORPTION OF THE HERBICIDES Lazar M. Kaluđerović* 1, Zorica P. Tomić1, Rada Đurović-Pejčev2, Maja Milošević3 1Department for Soil Management, Faculty of Agriculture/ University of Belgrade, 2Laboratory of Chemistry, Institute ...
    ... adsorption of S-metolachlor was highest for HDTMA-montmorillonite with 1CEC saturation.  High sorption of examined herbicides on some organically modified montmorillonites creates an opportunity for application of these substrates as potentially useful material for removal of S-metolachlor ...

  • Petrographical and organic geochemical study of the subbituminous coal from the Dubrava field, Aleksinac basin (Serbia)

    Željana Sekulić, Ksenija Stojanović, Achim Bechtel, Reinhard Sachsenhofer, Miomir Petrović, Ivan Kojić, Dragana Životić (2019)
    ... decrease of content of short-chain (С15-Сг0) and increase of long-chain (Cz6-Ca3) homologues. The obtained results suggest lowering of the water table during the formation of the Main coal seam. This change resulted in lesser inundation and deposition of MM associated with smaller input of bacterial ...
    ... ratios (6'3) of individual biomarkers were used to evaluate the origin and depositional environment of OM. The content of vitrinite group macerals increases from top to bottom of the Main coal seam which is associated with a notable decrease of liptinite and mineral matter (MM). Contents of collotelinite ...
    ... Development Office - Belgrade, Makedonska 33, 11000 Belgrade, Serbia 5; University of Belgrade, Innovation Center of the Faculty of Chemistry, Studentski trg 12-16, 11000 Belgrade, Serbia 6; University of Belgrade, Faculty of Mining and Geology, Đušina 7, 11000 Belgrade, Serbia *: Corresponding Author: ...

  • 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)
    ... rodnimuzej.rs Pottery making in Rujište near the Municipality of Ražanj (Central Serbia) is one of the most archaic ways of producing ceramics. “Crepulja” – bread-baking pan, a specific type of pottery, is made of two types of clay that are excavated exclusively at the location called Crepulja’s ...
    ... Sofia  Institute of Mineralogy and Crystallography “Acad. Ivan Kostov”, Bulgarian Academy of Sciences, Sofia  National Museum of Natural History, Bulgarian Academy of Sciences, Sofia  Sofia University “St. Kliment Ohridski”, Sofia  University of Mining and Geology “St. Ivan Rilski”, Sofia ...
    ... vessels meant for thermal processing of food. The technic of making of this bread-baking pans -crepulja- is very simple at first sight – hand-making with the help of several wooden and metal tools (Petrović, 1936; Djordjević, 2021) but it is also the optimal way of making these ceramic vessels. Nothing ...

  • Flyrock induced by blasting in surface mining

    Milanka Negovanović, Lazar Kričak, Snežana Ignjatović, Stefan Milanović, Jovan Marković, Nikola Simić, Rade Šarac (2022)
    Miniranje predstavlja i dalje najefikasniji i najjeftiniji način eksploatacije velikih količina čvrstih mineralnih sirovina na površinskim kopovima. Energija eksplozije se koristi za fragmentaciju čvrste stenske mase do zahtevane granulacije. Pored pozitivnih efekata miniranja, postoje i određeni neželjeni efekti svakog procesa miniranja koji se mogu javiti, a to su: potresi tla, razletanje komada stene, vazdušni udari, otrovni i zagušljivi gasovi i prašina. Razletanje komada stene je nekontrolisano izbacivanje fragmenata odminirane stenske mase i predstavlja jedan od glavnih izvora materijalne štete ...
    razletanje, bušenje, miniranje, površinska eksploatacija, bezbednost, nesreća

  • Advancing Sentiment Analysis in Serbian Literature: A Zero and Few-Shot Learning Approach Using the Mistral Model

    Milica Ikonić Nešić, Saša Petalinkar, Mihailo Škorić, Ranka Stanković, Biljana Rujević (2024)
    Ova studija predstavlja analizu sentimenta srpskih starih romana iz perioda 1840-1920, koristeći veliki jezički model (LLM) Mistral za tehniku učenja sa zasnovani na takozvanim "zero" i "few-shot" pokušajima. Glavni pristup uvodi inovacije osmišljavanjem istraživačkih upita (promptova) uključuju tekst sa uputstvom za klasifikaciju bez primera i na osnovu nekoliko primera, omogućavajući jezičkom modelu da klasifikuje osećanja u pozitivne, negativne ili objektivne kategorije. Ova metodologija ima za cilj da pojednostavi analizu osećanja ograničavanjem odgovora, čime se povećava preciznost ...
    zero-shot, few-shot, sentiment, Serbian, Mistral model

  • Late and post-collisional tectonic evolution of the Adria-Europe suture in the Vardar Zone

    Emő Márton, Marinko Toljić, Vesna Cvetkov (2022)
    The Vardar Zone is a product of the Triassic-Jurassic opening of the Neotethys, Jurassic obduction, Late Cretaceous/Paleogene consumption of the oceanic crust and continental collision. During the last process, the Eastern Vardar Zone was thrust over the Central and eventually both onto the Western Vardar Zone. The present paleomagnetic and structural study provided new results from the first two zones in the Belgrade area. The younger set of data, together with published ones from the third zone, provide firm ...
    Adria–Europe suture, Vardar Zone, Paleomagnetism, Thrusting, Vertical axis rotation

  • 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 ...

  • The number of unimodular roots of some reciprocal polynomials

    Dragan Stankov (2020)
    We introduce a sequence P2n of monic reciprocal polynomials with integer coefficients having the central coefficients fixed. We prove that the ratio between number of nonunimodular roots of P2n and its degree d has a limit when d tends to infinity. We present an algorithm for calculation the limit and a numerical method for its approximation. If P2n is the sum of a fixed number of monomials we determine the central coefficients such that the ratio has the minimal limit. ...
    Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomials

  • Vebran Web Services for Corpus Query Expansion

    Ranka Stanković, Miloš Utvić (2020)
    U ovom radu se govori o razvoju veb usluga Vebran i njihovoj primeni u poboljšanju pretraživanja korpusa. Veb-servisi Vebran koriste se za konsultovanje spoljnih leksičkih izvora za srpski jezik (uglavnom elektronski morfološki rečnici i srpski Vordnet) i proširivanje korisničkih upita radi dobijanja relevantnijih rezultata iz srpskih korpusa.
    corpus search, web service, Serbian lexical resources, query expansion
    ... University of Belgrade Faculty of Mining and Geology Miloš Utvić milos.utvic@fil.bg.ac.rs University of Belgrade Faculty of Philology Belgrade, Serbia 1 Introduction It is generally known that users typically formulate very short instead of long and complex queries. The lemmatization of corpora ...
    ... processors of OCWB (CQP) and NoSketch Engine (Manatee) in the following way: – user can request that particular term X in a given query should be re- placed with lemmas or word forms of terms which are semantically re- lated to X in some manner (synonyms of X, antonyms of X, meronyms of X, hyponyms of X, hypernyms ...
    ... SrpKor2013 The Corpus of Contemporary Serbian (SrpKor) was established in 2002, at the initiative of Professor Ljubomir Popović, with the aim of enabling researchers to consult the chosen collection of Serbian texts via the Internet (Vitas and Krstev, 2012). The first version of SrpKor, SrpKor2003, has ...

  • 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
    ... 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 ...
    ... 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 A Description of Morphological Features of Serbian: a Revision ...
    ... encountered in the previous versions, such as lack of attributes or attribute values, explicit statement of valid combinations of attribute and values. We expect that our description will transform without loss of information in the new version of MULTEXT-East format. 7. References Courtois, B ...

  • New approach to correlation of hydrocarbon reservoirs in sandstone layers of the "Mokrin" field"

    Saša Ivanišević, Dejan Radivojević (2018)
    геофизички каротаж, депозиционе средине, лежишта угљоводоника, миоцен, пост‐ рифтнo, секвенциона стратиграфија
    ... s  of the shape and characteristics of curves of gamma ray  (GR) and specific resistivity  (RT)  logs.   Funnel  shape of  the GR  log points  to  the  reduction  in  the basin water  level and  the  increase  in  the  level of  depositional energy, which leads to the reduction in the content of sha ...
    ... inconsistencies  in the selection of markers  in designation and correla‐ tion of hydrocarbon reservoirs, this approach has  led to  incorrect assessments of oil and gas reserves,  confusion in the interpretation of hydrodynamic measurements and reduced efficiency in the process of  reservoir management. As ...
    ... earch, the new approach to  correlation of oil and gas reservoirs of the “Mokrin” field is presented through the correlation of strati‐ graphic  units  based  on  the  interpretation  of  depositional  environments  executed  according  to  the  principles of sequence stratigraphy.      MATERIAL AN ...

  • Fragmentation Size Prediction of Blasted Material Using a Specialized Software for Drilling and Blasting

    Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić, Miljan Gomilanović (2024)
    Design and optimizing the drilling and blasting parameters, should fill the requirements for the capacity, fragmentation size, and technical characteristics of loading and transport equipment, and enable a safe work at the open pit. Besides mentioned, it also achieves the minimal impact on the environment of the open pit and decreases the negative effects on the environment, especially in the blast vibration and flyrock. To obtain the best possible blasting effects and consider all the factors, a specialized software is ...
    optimization, O-Pitblast, drilling, blasting, fragmentation size

  • Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry

    Steven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti (2021)
    Self-engineering is a relatively new branch of knowledge that aims to understand how systems could “autonomously” re-configure or repair themselves without the intervention of the operators. A direct field of application is within the maintenance spectrum. Having systems or machines capable of self-detecting or even self-repairing could represent a game-changer, in capital asset fields such as the mining industry in particular. This paper aims to investigate the possible benefits and challenges of self-engineering / self-maintenance concerning mining machines, specifically bucket-wheel ...
    self-engineering, self-maintenance, maintenance operations, mining industry, bucket-wheel excavator, gearbox revitalization

  • NMR kinetic studies of the interactions between [Ru(terpy)(bipy)(H2O)]2+ and some sulfur-donor ligands

    Aleksandar Mijatović, Biljana Šmit, Ana Rilak, Biljana Petrović, Dragan Čanović, Živadin D. Bugarčić (2012)
    Reakcije supstitucije monofunkcionalnog [Ru(terpi)(bipi)(H2O)]2+ kompleksa, gde je terpi = 2,2′:6′,2″-terpiridin i bipi = 2,2′-bipiridin, sa biološki relevantnim sumporo donorskim ligandima, kao što su tiourea, l-metionin, l-cistein i glutation, proučavane su u vodenim rastvorima tehnikom 1H i 13C NMR spektroskopije. Sve reakcije su proučavajne na pH 7,4, u prisustvu fosfatnog pufera, da bi se oponašalo fiziološko okruženje tokom procesa supstitucije. Reakcije se izvode na 295 K pod uslovima reakcija drugog reda. Uočeni rezultati pokazuju da brzina supstitucije snažno zavisi ...
    Materials Chemistry,Inorganic Chemistry,Physical and Theoretical Chemistry

  • The Usage of Various Lexical Resources and Tools to Improve the Performance of Web Search Engines

    Krstev Cvetana, Stanković Ranka, Vitas Duško, Obradović Ivan (2008)
    In this paper we present how resources and tools developed within the Human Language Technology Group at the University of Belgrade can be used for tuning queries before submitting them to a web search engine. We argue that the selection of words chosen for a query, which are of paramount importance for the quality of results obtained by the query, can be substantially improved by using various lexical resources, such as morphological dictionaries and wordnets. These dictionaries enable semantic ...
    LR web services, MultiWord Expressions & Collocations, Information Extraction, Information Retrieval
    ... 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 The Usage of Various Lexical Resources and Tools to Improve the Performance of Web ...
    ... brief description of resources is given, followed by an outline of the web tool which enables their integration. Finally, a set of examples is chosen in order to illustrate the use of the lexical resources and tool in question. Results obtained for these examples show that the number of documents obtained ...
    ... Ranka Stanković2 , Duško Vitas 3 , Ivan Obradović4 1 professor, Faculty of Philology, Belgrade, 2 assistant, Faculty of Mining and Geology, Belgrade 3 professor, Faculty of Mathematics, Belgrade, 4 professor, Faculty of Mining and Geology, Belgrade E-mail: cvetana@matf.bg.ac.yu, ranka@rgf.bg.ac ...

  • 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. ...
    Morfološki rečnici, jezički resursi, Leksimirka
    ... dictionary used for its production consists of automatically generated entries representing all inflectional forms of a DELAS dictionary. It consists of a word form, its lemma, word type designation, semantic mark- ers and a set of grammar categories. Here is an example of one line from a DELAF dictionary: ...
    ... Opportunities for working with dictio- naries of MWUs are also available. The most important one is the automatic generation of the complex DELAC lemmas from a simple list of their basic forms. After years of working on dictionary expansion, the number of lexical records and categories (semantic and ...
    ... Krstev, Cvetana. Processing of Serbian. Automata, Texts and Electronic Dic- tionaries. Faculty of Philology of the University of Belgrade, 2008 Krstev, Cvetana, Ranka Stanković, Duško Vitas and Ivan Obradović. “WS4LR - a Worksation for Lexical Resources”. In Proceedings of the Fifth Interantional Conference ...

  • Substitution reactions of some novel sterically hindered monofunctional Pd(II) complexes

    Aleksandar Mijatović, Jovana Bogojeski, Biljana Petrović, Živadin D. Bugarčić (2011)
    Reakcije supstitucije monofunkcionalnih kompleksa [(TLtBu)PdCl]+ i [Pd(tpdm)Cl]+, gde je TLtBu = 2,6-bis[(1,3-di-terc-butilimidazolin-2-imino)metil]piridin i tpdm = terpiridindimetan, sa nukleofilima kao što su: tiourea, I−, Br−, NO2−, piridin i dimetil-sulfoksid (DMSO) proučavani su u 0,1 M vodenom rastvoru NaClO4 u prisustvu 10 mM NaCl. Reakcije su sprovedene na tri različite temperature (288, 298 i 308 K) korišćenjem tehnike zaustavljenog protoka na različitim temperaturama. Reakcije supstitucije su praćene pod uslovima pseudo prvog reda sa velikim viškom nukleofila. Dobijeni rezultati pokazuju da kompleks ...
    Materials Chemistry, Inorganic Chemistry, Physical and Theoretical Chemistry
    ... other side, the bulkiness of two methyl groups in the molecule of DMSO as well as the bulkiness of the inert tridentate ligands in the structure of the studied complexes could prevent the formation of the metal–ligand bond and slow down the rate of the substitution. The reactivity of pyridine is almost the ...
    ... the complexes with TLtBu ligand due to the bulk- iness of the inert tridentate ligands. Also, the presence of t-Bu groups on the terminal imadazole rings of TLtBu ligand significantly slow down the rate of the substitution. The order of reactivity of used ligands is: thiourea > I� > Br� > NO2 � > pyridine ...
    ... with TL" ligand due to the bulk- Substitution iness of the inert tridentate ligands. Also, the presence of t-Bu groups on the terminal imadazole rings of TL" Kinetics ligand significantly slow down the rate of the substitution. The order of reactivity of used ligands is: Mechanism thiourea > I~ > Br- > ...

  • Tectonic evolution of the Circum-Moesian orocline of the Carpatho-Balkanides: Paleomagnetic constraints

    Emő Márton, Vesna Cvetkov, Miodrag Banješević, Gábor Imre, Aleksandar Pačevski (2024)
    Apuseni-Banat-Timok-Srednogorie belt, danubicum, paleomagnetism, oroclinal bending

  • Depth estimation of archeological objects using Euler 3D deconvolution of magnetic data

    Vesna Cvetkov, Ilija Vasiljević, Mirko Petković (2015)