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Упит dcterms_subject_txt:eksploatacija lignita

315 items

  • P-T analiza uglja RB Kolubara

    Rada Vitomir (2024)
    Rudarski basen Kolubara predstavlja jedno od najvažnijih ležišta lignita u Republici Srbiji i ključni je faktor u snabdevanju zemlje energijom. Kvalitet uglja iz ovog basena direktno utiče na efikasnost termoelektrana i zadovoljenje energetskih potreba. U ovom radu, opisan je značaj tehničke i elementarne analiza uglja kako bi se utvrdili fizičko-hemijski parametri uglja iz Rudarskog basena Kolubara. U drugom delu rada dat je opis P-T analize uglja i njen značaj za ocenu mogućnosti čišćenja uglja. Takođe, dati su i rezultati ...
    Rudarski basen Kolubara, pliva tona analiza, lignit, kvalitet uglja, energetska efikasnost
    ... ključnih horizonata uglja koji su od posebnog značaja za eksploataciju (Kisić i sar., 2013). Kvalitet uglja u basenu Kolubara varira, pri čemu se uglavnom radi o lignitu sa niskim sadržajem sumpora i pepela. Ove karakteristike čine kolubarski lignit pogodnim za upotrebu u termoelektranama, koje su glavni ...
    ... Republici Srbiji, koji se nalazi u zapadnom delu zemlje, u blizini grada Lazarevca. Basen je poznat po rezervama lignita, što ga čini ključnim faktorom u snabdevanju zemlje energijom. Eksploatacija uglja u ovom regionu ima dugu istoriju, koja datira Još iz 19. veka, ali je intenzivni razvoj rudarstva započeo ...
    ... formiranju i distribuciji ugljenih slojeva, kao i u određivanju pristupačnosti ovih resursa za eksploataciju (Đukičin, Đorđević, i Milanković, 2014). Ugljeni slojevi u basenu Kolubara su uglavnom ligniti, koji su nastali akumulacijom biljnog materijala u močvarnim uslovima. Ovi slojevi se karakterišu ...

  • Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine

    Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić (2021)
    The production of lignite in large open-pit mines is mainly performed with continuously operating equipment, where bucket-wheel excavators, bucket-chain excavators, belt conveyors, and spreaders are the basic machines. Smaller machines, usually of discontinuous operating nature, are commonly categorized as auxiliary machines. This paper presents the research related to the analysis of auxiliary machine parameters with the case study for a hydraulic excavator. The purpose of the analysis was to develop a model of rating quality of service of the ...
    Fuzzy theory, hydraulic excavator, selection, quality of service, asset management

  • Application of the Fuzzy theory in the evaluation of operating parameters of auxiliary mechanization on open-cast coal mine, case study: pipelayers

    Stevan Djenadić, Miloš Tanasijević, Filip Miletić, Predrag Jovančić (2022)
    Achieved operating parameters are the main indicator of the work quality and selection of mining machines. The effectiveness of a coal mine is correlated with the availability of basic and auxiliary machines. The main task of auxiliary machines in lignite mines is to achieve optimal working conditions. From an economic point of view, auxiliary machines generate up to 20% of the lignite mines' total costs. These are the primary reasons for analyzing their current work and making decisions in ...
    upotrebni kvalitet, fazi teorija, rudarske mašine

  • Dehydroicetexanes in sediments and crude oils: Possible markers for Cupressoideae

    Hans Peter Nytoft, Geir Kildahl-Andersen, Sofie Lindström, Frode Rise, Achim Bechtel, Danica Mitrović, Nataša Đoković, Dragana Životić, Ksenija A. Stojanović (2019)
    Two previously unidentified dehydroabietane isomers were isolated from Miocene Serbian lignite and Rhaetian (Late Triassic) coaly mudstones from South Sweden and characterized using NMRspectroscopy as cis- and trans-dehydroicetexane. Both have a 9(10?20)-abeo-abietane or icetexane skeleton, consisting of a 6-7-6 tricyclic framework with seven carbons in ring B instead of the usual six in common diterpanes of the abietane-type. Dehydroicetexanes can be detected using GC-MS-MS in m/z 270?146 chromatograms without interference from dehydroabietane or other isomers. Dehydroicetexanes are often abundant ...
    Geochemistry and Petrology

  • Uporedni prikaz proizvodnje električne energije iz uglja zemalja Evrope sa najvećim udelom: politika i projekcija proizvodnje

    Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić (2022)
    Energetski razvoj zemalja Evrope decenijama je bio baziran na uglju. Instalisana snaga svih energetskih kapaciteta koji su zasnovani na uglju je preko 2000 GW. Ugalj je i dalje od bitnog značaja za dobijanje električne energije u Evropi. I pored toga što postoji veliki potencijal uglja, trend je smanjenja proizvodnje električne energije iz uglja do 2050. godine. Imajući u vidu Zelenu agendu i politiku EU, zemlje Evrope se okreću obnovljivim izvorima energije. Srbija u okviru obnovljvih izvora ima potencijala prevashodno ...
    ugalj, električna energija, 2050. godina, projekcija proizvodnje

  • 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

  • Analiza osnovnih indikatora upotrebnog kvaliteta mašina pomoćne mehanizacije na površinskim kopovima uglja

    Stevan Đenadić, Dragan Ignjatović, Predrag Jovančić, Milena Lekić, Žarko Aleksić, Ivan Janković (2022)
    Izbor optimalnog tipa mašine i adekvatno upravljanje kroz životni vek je kompleksan zadatak. Osnovna pitanja koje se postavljaju prilikom rešavanja ovog zadatka vezana su za stepen zadovoljenja rada mašine i optimalan trenutak zamene iste. U ovom radu je izvršena analiza rada dozera koji su u radu na površinskom kopu lignita RB Kolubara. Analizom je obuhvaćeno 4 različita proizvođača dozera a to su: Caterpillar, Dressta i Shantui i Liebherr. Analiza je izvršena sa aspekta ukupnih troškova koji se stvaraju i ...
    rudarstvo, mehanizacija, upotrebni kvalitet, troškovi, empirijska raspoloživost

  • A Model for Determining Fuzzy Evaluations of Partial Indicators of Availability for High-Capacity Continuous Systems at Coal Open Pits Using a Neuro-Fuzzy Inference System

    Miljan Gomilanović, Miloš Tanasijević, Saša Stepanović, Filip Miletić (2023)
    This paper presents a model for determining fuzzy evaluations of partial indicators of the availability of continuous systems at coal open pits using a neuro-fuzzy inference system. The system itself is a combination of fuzzy logic and artificial neural networks. The system availability is divided into partial indicators. By combining the fuzzy logic and artificial neural networks, a model is obtained that has the ability to learn and uses expert judgment for that learning. This paper deals with the ...
    системи, континуални системи експлоатације (роторни багер-транспортер-дробилично постројење), рударство, расположивост, меко рачунарство, фази логика, ANN, ANFIS

  • The Potential of Biomarkers to Distinguish Lower and Middle Miocene Lignites from the Coal-Mining District of Lusatia

    I. Kojic, J. Kus, D. Zivotic, K. Stojanovic (2021)
    ... one, also Middle Miocene lignite, where PAHs prevail over steroids, being order of magnitude more abundant than in other samples. Among aromatic non-hopanoid terpenoids, 24,25-dinorlupa-1,3,5(10)-triene dominates in all samples, with the exception of Middle Miocene lignite enriched in PAHs, where ...
    ... potential of biomarkers to distinguish Lower and Middle Miocene lignites in relation to sources and depositional environment of organic matter (OM). Lignite samples were collected from the 2nd Miocene Seam Horizon or its equivalent of Piskowitz (Lower Miocene) and Welzow-Süd (Middle Miocene) open-cast ...

  • Properties of fly ash and slag from the power plants

    Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić (2016)
    This paper describes the physical, chemical and mineral properties of ash and slag, which were taken from thermal power plants Nikola Tesla A, Nikola Tesla B, Kostolac A and Kostolac B. The knowledge of the mineralogical material composition is important because the type of minerals directly determines the properties of the fly ash and slag and their possible application. Laboratory tests showed that ash and slag samples consist of the following minerals: amorphous materials, quartz, feldspar, mullite, melilite, cristobalite, ...
    fly ash, slag, physical composition, chemical composition, mineral composition, X-ray diffraction method
    ... al., 2013). Since 1896, about 883.2Mt of lignite in total, has been pro- duced from the Kolubara basin, of which 866.8Mt was form open pit mines and 16.3Mt from underground mines (active until 1974). Annually, the Kolubara basin produces about 30Mt lignite, which amounts to 70% of the total coal ...
    ... coal production in Serbia. According to the Geological Survey of the Kolubara basin, the lignite re- sources and reserves are currently estimated at 2811Mt. Most of the lignite produced (90%) is used for electricity generation in thermal power plants „Nikola Tesla A” (NT A) and „Nikola Tesla B” (NT ...
    ... PPNT A is 4 km from Obrenovac, PPNT B is located 16 km upstream from PPNT A (Fig. 1). Both PPNT use coal from the Kolubara basin. The Kolubara lignite basin is economically one of the most important coal basins in Serbia. It is located about 60km SSW of Belgrade, and covers an area of almost 600km2 ...

  • Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2017)
    Large collections of textual documents represent an example of big data that requires the solution of three basic problems: the representation of documents, the representation of information needs and the matching of the two representations. This paper outlines the introduction of document indexing as a possible solution to document representation. Documents within a large textual database developed for geological projects in the Republic of Serbia for many years were indexed using methods developed within digital humanities: bag-of-words and named ...
    ... This partially solves the problem of rich morphology that is characteristic for Serbian. For instance, scanning with lignit will also retrieve inflected forms lignita, lignitu, lignitom, etc. However, this solution is also a source of many false retrievals, especially when keywords are very short and ...
    ... is generated. For example, if the user is interested in projects that deal with the research of “lignite coal in Tamnava region”, then mineral resource is selected as one facet and the words lignit ‘lignite’ and ugalj ‘coal’ are defined for keyword search, and the system will search for any of these two ...
    ... OR Ub” (two mining sites) in the location facet and “ugalj OR lig- nit” (coal or lignite) keywords in the mineral resource facet. The initial system would identify lignita (as a substring of the genitive form of lignit) and Tamnava as matches (underlined by a thicker single line) but would fail to identify ...

  • Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine

    Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović (2019)
    Availability is one of the most used terms in maintainability engineering. This concept is used to denote: The quality of service of an engineering system, i.e., machines, weak points’ analysis, asset management, as well as making decisions in the process of life cycle management. Availability is an overall indicator and contains partial indicators that are oriented towards reliability, maintenance, and logistical support. Availability presents a variable value and changes in time and space. Usually, availability is shown as the ...
    raspoloživost, fazi teorija, AHP višekriterijumska analiza, eksperska ocena, buldozer
    ... Измењено: 2023-10-14 04:29:43 Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović Дигитални репозиторијум Рудар ...
    ... у Београду [ДР РГФ] Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open- Pit Lignite Mine | Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović | Energies | 2019 | | 10.3390/en12214044 ...
    ... energies Article Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine Stevan Djenadic 1,*, Dragan Ignjatovic 1, Milos Tanasijevic 1, Ugljesa Bugaric 2, Ivan Jankovic 3 and Tomislav Subaranovic 1 1 Faculty of Mining ...

  • A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)

    Jelena Ratković, Dušan Polomčić, Dragoljub Bajić, Bojan Hajdin (2016)
    ... Power Industry of Serbia. Since World War II, it has produced more than 580,000,000 tons of coal. Every other kilowatt in Serbia comes from KCB’s lignite (brown coal). A daily extraction rate of as much as 100,000 tons of coal ensures reliable operation of the thermal power plants Nikola Tesla and ...
    ... 2013a; Polomčić et al. 2013b; Polomčić et al. 2014; Šubaranović et al. 2013). KCB’S Tamnava - West Field is the largest and most modern open-cast lignite mine in Serbia. In 2015, its total output was 11,600,000 tons of coal, or about 15.5% more than the annual budget. Among the major recent hyd ...
    ... were determined on the basis of data collected from numerous exploration boreholes, distributed across the study area. According to the “Report on Lignite Reserves at Tamnava - West Field of the Kolubara Coal Basin as on 31 December 2009” (Kitanović, 2010), there were 796 exploration boreholes from ...

  • P-T analiza RMU Bitola – krupne klase

    Nemanja Dobrosavljević (2024)
    Cilj ovog diplomskog rada je bio ispitivanje mogućnosti i tehnologije čišćenjauglja, kao i predstaviti rezultate pliva – tone analize koja ima za cilj ocenu mogućnosti čišćenja uglja - krupnih klasa posmatranog uzorka. Da bi se ispitivanje i analiza mogućnosti čišćenja rovnog uglja u REK Bitola uspešno priveli kraju, moralo se uraditi uzorkovanje reprezentativnog uzorka iz koga se potom izdvaja prvi deo koji služi za određivanje sadržaja vlage. Pored tog dela iz uzorka se izdvaja i drugi njegov deo koji će ...
    ugalj, lignit, Bitola, PT analiza, pliva-tone analiza, čišćenje uglja, suvi ugalj, vlažan ugalj, pepeo, donja toplotna moć, čist ugalj, jalovina, bilans
    ... CO». 24 PLIVA - TONE ANALIZA Eksploatacija uglja iz njegovih ležišta uvek je praćenja pojavom nceke količine jalovine. Važno je napomenuti da Jalovina nije striktno vezana samo za površinsku eksploataciju ugljeva već se pojavljuje i u podzemnoj eksploataciji. Količina jalovine u otkopanom uglju ...
    ... u pitanju stariji ugljevi (kameni ugljevi i antraciti). Postupak se ređe sprovodi kod mrkih, dok se kod mlađih ugljeva, odnosno lignita nikako ne praktikuje. Lignit ima svoju drvenastu građu i izraženo svojstvo upijanja vode te se ne flotira. Na sam postupak flotacijske koncetracije uglja utiče ...
    ... Takođe, u opštem delu je prikazana i namena tj. upotreba ugljeva koji su interesantni za eksploataciju te i tehnologije koji se koriste za čišćenje. Naravno da rad ne bi bio potpun ukoliko ceo okvir eksploatacije uglja ne bi smo posmatrali kroz prizmu ekonomske isplativosti kreirane kroz zahteve tržišta ...

  • Optimizacija dužine strele rotornih bagera u funkciji stabilnosti kosina i efektivnosti rada na površinskim kopovima lignita Srbije

    Branko M. Petrović (2016-07-12)
    Rotorni bageri su mašine koje se u današnje vreme najviše primenjuju uprocesu masovne eksploatacije uglja zahvaljujući, pre svega, nizu tehničkoeksploatacionihprednosti u odnosu na druge vrste bagera. Raznovrsnirudarsko-tehnički zahtevi otkopavanja doprineli su razvoju nekoliko tipova ovihmašina, tako da svaki od njih ima svoje prednosti i nedostatke u odnosu nadrugi tip.Predmet istraživanja u disertaciji odnosi se na izbor optimalnekonstrukcije strele bagera i njene usaglašenosti sa uslovima radne sredine kojiće vladati na površinskim kopovima lignita Srbije, imajući u vidu složene usloveeksploatacije (velika ...
    površinski kop, parametri bloka, kapacitet, rotorni bager, strelabagera, geomehanika, stabilnost kosina, ekonomija
    ... BAGERA U FUNKCIJI STABILNOSTI KOSINA I EFEKTIVNOSTI RADA NA POVRŠINSKIM KOPOVIMA LIGNITA SRBIJE Rezime Rotorni bageri su mašine koje se u današnje vreme najviše primenjuju u procesu masovne eksploatacije uglja zahvaljujući, pre svega, nizu tehničko- eksploatacionih prednosti u odnosu ...
    ... konstrukcije strele bagera i njene usaglašenosti sa uslovima radne sredine koji će vladati na površinskim kopovima lignita Srbije, imajući u vidu složene uslove eksploatacije (velika dubina sinklinalnog zaleganja uglja, neophodnost selektivnog rada, prisutnost nepovoljnih materijala sa stanovišta ...
    ... uslove radne sredine koji će u narednom periodu vladati na našim površinskim kopovima lignita (P.K. RADLJEVO, P.K. POLJE E, P.K. POLJE F, P.K. DRMNO i dr.) imajući, pre svega, u vidu složene uslove eksploatacije kao što su velika dubina sinklinalnog zaleganja, neophodnost selektivnog rada, nepovoljni ...

  • Indexing of textual databases based on lexical resources: A case study for Serbian

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2015)
    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 ...
    ... characterizes Serbian, as a language belonging to the South-Slavic Language family. For instance, scanning with lignit ‘lignite’ will also retrieve inflected forms lignita, lignitu, lignitom, etc. Search results are ranked on the basis of weight factors assigned to individual fields in the function of ...
    ... logging; Naftagas 9 geofizički karotaž ; Naftagas NIS 0.118 0.113 0.004 geophysical logging; Naftagas NIS 10 ugalj lignit ; Kostolac Požarevac 0.285 0.732 -0.447 coal lignite; Kostolac Požarevac MAP 0.440 0.395 0.045 Improvement 11.49% The evaluation revealed that some NEs referring to the same ...

  • Effectiveness Analysis of Different Bucket-wheel Excavators

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić (2021)
    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 ...
    bucket-wheel excavator, open-pit coal mine, mining, multi-criteria decision methods

  • Assessments of effects of implementation of strategic plans for development of Belgrade District heating system

    Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Miodrag Grujić (2020)
    The district heating system (DHS) is one of the key elements of the Belgrade energy system. Overview of the current state and basic characteristics of the DHS are presented in this paper. The focus is on the planned development of DHS and on the analyses of effects of realization of measures and projects defined by strategic documents related to DHS which are adopted by city authorities (Development Strategy of DHS and Strategy of Belgrade Development). Two exploratory scenarios were ...
    Daljinsko grejanje, LEAP, Primarni energetski faktor, Uvozna zavisnost, CO2 emisija

  • Rezultati ispitivanja parametara čvrstoće i dinamičkih svojstava mermera i mogućnost njihove korelacije

    Jelena Majstorović-Necković, Vladimir Čebašek, Veljko Rupar (2023)
    Ispitivanja stena kao radne sredine, odnosno materijala sa kojim se gradi, na kome se gradi i u kome se gradi, svojom složenošću zahteva njeno svestrano izučavanje po velikom broju parametara. Zadatak Mehanike stena je da što bolje upozna ponašanje stenske mase i njenu otpornost na dejstvo pritiska, zatezanja i smicanja, kao i dinamičkih svojstava. Poznavanje navedenih parametara i njihova korelacija omogućavaju pouzdaniji izbor parametara za projektovanje danas sve zahtevnijih uslova kako podzemne, tako i površinske eksploatacije. U ovom radu ...
    mermer, jednoosna čvrstoća na pritisak, čvrstoća na istezanje, brzina longitudinalnih elastičnih talasa, korelacija

  • Predlog metodologije za merenje performansi procesa

    Kukrika Milan, Dimitrijević Bojan (2012)