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Упит dcterms_subject_txt:diagnostics of operating coditions,Random Forest

2844 items

  • The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers

    Dragan Ignjatović, Predrag Jovančić, Stevan Đenadić, Ivan Janković, Ivica Ristović (2019)
    One of the most important prerequisites for the successful operation of the open-cast lignite mine is to carry out all the auxiliary works timely with the necessary quality. The most important and most commonly used auxiliary machines are bulldozers. Engaging time of bulldozers use is in direct relation with the coefficients of the time and capacity utilization of the continuous system for the excavation of coal and tailings, which indicates their importance. More than 100 bulldozers have been hired ...
    open-cast coal mine, auxiliary works, bulldozers, optimization, availability
    ... Analysis showed that profit life (economical life) of dozer CAT D8R operating on open-cast mines of EPS is around 7 years, while optimal operating time from the aspect of availability is 8 years. Considering other types of bulldozers operating on open-cast mines of EPS (TD25M, TD25H, 752 / 754, PD320Y-1, SD32W) ...
    ... years and achieved 25,000 moto-hours (operating hours). Such structure of age and achieved operating hours 15 the reason for having more than twice as much available dozers in relation to operating ones. It should be noted that dozers are generating 45 — 50% of all auxiliary equipment costs. This implies ...
    ... quality, operating quality, апа others. Empirical data shows that dozer's life on open-cast mines is 25-30,000 hours, i.e. around 10 years of operation. However, some data also shows that dozers after 6% year ог operation аге having lesser efficiency which is indicated by reduced number of effective ...

  • Model of room and pillar production planning in small scale underground mines with metal price and operating cost uncertainty

    Gligorić Zoran, Gligorić Miloš, Dimitrijević Bojan, Grozdanović Ines, Milutinović Aleksandar, Ganić Aleksandar, Gojković Zoran (2018)

  • Unvestments in Geological Exploration and Afectation on Mining Operating Cash Costs at Lignite Open Pits Kolubara (Lazarevac), Serbia

    Vuckovic Bogoljub, Dimitrijevic Bojan (2018)

  • The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)

    Marina Čokorilo Ilić, Ana Mladenović, Marina Ćuk, Igor Jemcov (2019)
    Geography, Planning and Development,Aquatic Science,Biochemistry,Water Science and Technology
    ... 603 2 of 10 The water-conveyance tunnel of Hydropower Plant (HPP) Pirot is a good example of extensive monitoring adapted to complex hydrogeologic conditions, regarding the operating conditions of the tunnel and potential hydraulically active zones. 2. Study Area The water-conveyance tunnel of HPP Pirot ...
    ... the drainage point of a deeper hydrogeologic system characterized by hypogenic conditions. Water 2019, 11, 603 3 of 10 Figure 2. Geological map of the study area. 3. Materials and Methods Research activities and the selection of methods depended on the operating regime of the water-conveyance ...
    ... (instant response of observation well PP-3) while the tunnel was online, when both the tunnel and the hydrogeologic environment were under the influence of the pressure of the transported water (Figure 5). In the full operating mode of the HPP (4–5 h/day), at PP-3 the transport of water relieved the ...

  • State and perspective of individual household heating in Serbia: A survey-based study

    Boban Pavlović, Dejan Ivezić, Marija Živković (2021)
    This paper presents the results of the household survey on individual household heating systems in Serbia. The survey was conducted in the period October to December 2020 with the participation of 1100 households with individual household heating systems. The information collected in the questionnaire can be separated into three main parts: basic household data, current heating system characteristics, and households’ perceptions and attitudes. The survey results provide unique and comprehensive information concerning individual household heating systems and the main ...
    Domaćinstva, Individualni sistemi grejanja, Korišćenje energije, Stavovi potrošača, Anketa, Srbija

  • Overwiew of In-Pit Crushing & Conveying Technology in Open Pit Mines

    Ali Nasirinezhad, Dejan Stevanović, Dragan Ignjatović, Petar Marković (2021)
    The conditions under which contemporary surface mining operations is carried out obviously becoming increasingly complex. In such complex conditions, the optimization of haulage systems as the technological phase with the largest share in the total operating costs, is very important from the aspect of achieving profitability of the mining project. In a large number of cases, the application of traditional haulage systems with trucks (as the most dominant type of haulage in open pit mines) does not lead to ...
    In Pit Crushing and Conveying, IPCC, open pit mining, haulage, optimization, costs saving

  • Uticaj ekstremnih procesa na rizike površinske eksploatacije

    Natalija Pavlović, Tomislav Šubaranović, Dragan Ignjatović (2022)
    Nepredvidivi ekološki negativni slučajni procesi mogu uticati na geo-tehnički sistem pri površinskoj eksploataciji ležišta mineralnih sirovina, što u velikoj meri uvećava rizike i ugrožava realizaciju proizvodnje. Kvantitativna analiza sa proračunom verovatnoća pojava ovakvih ekstremnih događaja i procenom odgovarajućih ekonomskih posledica, posebno u uslovima globalnih klimatskih promena, omogućava definisanje rizika i optimizaciju parametara sistema površinske eksploatacije.

  • Classification of Terms on a Positive-Negative Feelings Polarity Scale Based on Emoticons

    Mihailo Škorić (2017)
    The goal of this paper is to draw attention to the possibility of using emoticon-riddled text on the web in language-neutral sentiment analysis. It introduces several innovations in the existing framework of research and tests their effectiveness. It also presents a software tool especially made for that purpose, explains how it builds a database with sentimental value of terms and offers the user manual. Finally, it presents a software tool that tests the new database and gives some examples ...
    data mining, information extraction, emotions, text on the web
    ... with clients. 5.3 Possible deficiencies and improvements – The problem of possible random responses during the survey: Create a system that rejects the member who answered at random, for example, using an introduction of additional questions that requiring specific responses. In that way careless users ...
    ... values are non-random and representative, hich implies that this method of terms classification is pos- sible for any natural language using determiners, but it is still necessary to carry out a systematic evaluation. The algorithms used are still far from perfect, and in there is plenty of room for improvement ...
    ... using any version of the operating system that runs to 64 bit. The interface is user-friendly and entirely in Serbian. The goal in designing this software was that any researcher who speaks Serbian can use it independently, create a new database or use it for a new research. 3 A total of 143 users actually ...

  • Geoenvironmental Investigations at a Smelter Location in Bor (Serbia)

    Petar Papić, Zvonimir Milijić, Jana Stojković, Jovana Milosavljević, Maja Todorović, Marina Ćuk, Željko Kamberović (2014)

  • Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic

    Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković (2020)
    Artificial lift methods have applications in oil wells where oil production is no longer possible due to natural reservoir energy, so this necessary energy is added by introducing lift methods. In order to achieve optimum production, the selection of an artificial lift method is very important. This paper uses fuzzy logic as a mathematical and conceptual model for selection of the optimal artificial lift method. The outcome or IF-THEN rules, as the central part of the model, is based ...
    mehaničke metode, proizvodnja nafte, fazi logika, donošenje odluka, optimizacija
    ... mathematical and conceptual model of optimized selection is descripted in the following text by steps. Table 2. Characteristics and limitations of the application of artificial lifting methods [16]. Operating Parameters SRP ESP HP Gas Lift PCP Typical operating depth (m) 35–3828 348–3480 1740–3480 ...
    ... mathematical and conceptual model of optimized selection is descripted in the following text by steps. Table 2. Characteristics and limitations of the application of artificial lifting methods [16]. Operating Parameters SRP ESP HP Gas Lift PCP Typical operating depth (m) 35–3828 348–3480 1740–3480 ...
    ... the problem of selecting artificial lift methods and considered income, operational and investment costs as criteria. This author considered that the optimal method chosen should achieve the highest production at the lowest operating costs. The paper describes the methods of exploitation of oil with ...

  • Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining

    Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović (2019)
    Analitički hijererhijski proces (AHP), dozeri, eksploatacija uglja, površinski kopovi
    ... Consistency Ratio (CR) is defined using the following equation: CR = CI RI (5) where RI is the Random Consistency Index (Table 3) which depends on the number of analysed objects n. Table 3. The values of the Random Consistency Index (RI) (Saaty, 1991). n 1 2 3 4 5 6 7 8 9 10 RI 0.00 0.00 0.52 0.89 1.11 ...
    ... following equation: CICR= RI (5) where RI is the Random Consistency Index (Table 3) which depends on the number of analysed objects n. In order for the method to be correct one condition must be fulfilled. The result of the calculated value of the Consistency Ratio when it comes to consistency ...
    ... breaking piles, pushing scattered masses into the zone of effect of the bucket-wheel excavator, shaping slopes, cleaning the benches, pulling operating stations or other machines, checking the ground stability, etc. The classification of the auxiliary workings which are done using the dozer in the big ...

  • Linear-motor plunger pump increases lifting efficiency

    Bojan Martinović, Dušan Đekić, Dušan Danilović, Pavel Isaev (2022)
    plunger, linear, motor, pumps

  • Development of an integrated model for open-pit-mine discontinuous haulage system optimization

    Miodrag Čelebić, Dragoljub Bajić, Sanja Bajić, Mirjana Banković, Duško Torbica, Aleksej Milošević , Dejan Stevanović (2024)
    equipment selection, mine mechanization, expert judgment, linguistic variables, MCDM, FAHP

  • Effects of external noise on threshold-induced correlations in ferromagnetic systems

    Dragutin Jovković, Sanja Janićević, Svetislav Mijatović, Lasse Laurson, Đorđe Spasojević (2021)
    Изингов модел, праг детекције, екстерни шум

  • Model inteligentnog sistema adaptivnog upravljanja procesom prerade rude

    Ivana M. Jovanović (2016-01-13)
    U oblasti procesa prerade rude, flotacijska koncentracija predstavlja jednu od najznačajnijih i najčešće primenjivanih metoda separacije korisnih od nekorisnih minerala. Samim tim, veoma je važno osigurati uspešan rad flotacijskog postrojenja kroz dostizanje zadovoljavajućih tehno-ekonomskih pokazatelja. Cilj upravljanja procesom flotacijske koncentracije je upravo optimizacija kvaliteta i iskorišćenja korisne komponente u koncentratu uz maksimizaciju profita. Shodno tome, istraživanja na polju modelovanja i upravljanja ovim procesom zauzimaju značajno mesto u praksi kontolnog inženjenringa.Teorijska istraživanja u okviru doktorske disertacije obuhvatila su analizu položaja ...
    flotacijska koncentracija, modelovanje, upravljanje, inteligentni sistem, soft kompjuting, fazi logika, veštačke neuronske mreže
    ... G.J., 2012. The effect of flotation variables on the recovery of different particle size fractions in the froth and the pulp, International Journal of Mineral Processing, Vol. 106–109, pp. 70–77 231. Raj, K.J., Sathya, S.S, 2013. SVM and Random Forest Classification of Satellite Image with NDVI ...
    ... Gao, D., Zhang, Y.-X., Zhao, Y.-H., 2009. Random forest algorithm for classification of multiwavelength data. Research in Astronomy and Astrophysics 9 (2)pp. 220-226 75. Garcia Zuñiga, H., 1935. The efficiency obtained by flotation is an exponential function of time. Boletín Minero, Sociedad Nacional ...
    ... Optimisation of operating variables of fine coal flotation using a combination of modified flotation parameters and statistical techniques. International Journal of Mineral Processing 68, pp. 109–127 266. Suganyadevi, M.V., Babulal, C.K., 2014. Fast Assessment of Voltage Stability Margin of a Power ...

  • BEYOND 2020 - Geology explorations and open pit activities affectation in reclamation designing in Kolubara Coal Mines (KCM) Serbia, new considerations

    Bojan Dimitrijević, Bogoljub Vučković, Radmila Gaćina (2023)
    Geology explorations in KCM runs from 1936. year up to these days and still ongoing. Results in >7,200 drill holes with ≈600,000 m of core drilling and gave lignite ore resources of > 4,1Bt, which 1,15Bt are excavated since 1986. of XIX up to early years of XXI century. For further mining operations in open pits stay 1,5Bt of lignite. Under waste heaps are ≈80 km2, additional 85 km2 should be filled. All of that masses/areas were, are ...

  • Part of Speech Tagging for Serbian language using Natural Language Toolkit

    Ranka Stanković, Boro Milovanović (2020)
    Dok se razvijaju složeni algoritmi za NLP (obrada prirodnog jezika), osnovni zadaci kao što je označavanje ostaju veoma važni i još uvek izazovni. NLTK (Natural Language Toolkit) je moćna Python biblioteka za razvoj programa zasnovanih na NLP-u. Pokušavamo da iskoristimo ovu biblioteku za kreiranje PoS (vrsta reči) oznake za savremeni srpski jezik. Jedanaest različitih modela je kreirano korišćenjem NLTK API-ja za označavanje. Najbolji modeli se transformišu sa Brill tagerom da bi se poboljšala tačnost. Obučili smo modele na označenom ...
    obrada prirodnog jezika, mašinsko učenje, neuronske mreže
    ... [6]. Later attempts relied on CRF (Conditional Random Fields) [7-8] which is among supported technologies by NLTK and will be used for training one of the taggers. Introducing the dataset and the tagset will be done in the Section 2. The creation of multiple taggers is presented in Section 3. The ...
    ... Fig. 2. Dependence of the Lookup tagger accuracy on the number of the stored tags Aside embedded sequential tagger models available in the nltk.tag.sequential package, there are custom made models available in separate subpackages. CRF tagger is based on Conditional Random Fields [18]. HMM tagger ...
    ... vol. 12 no. 2 pp 36a-47a, Dec. 2011 [7] M. Constant, C. Krstev, and D. Vitas “Lexical Analysis of Serbian with Conditional Random Fields and Large-Coverage Finite-State Resources”, Proc. 7th Language and Technology Conference (LTC), Poznan, Poland, Nov. 2015 [8] N. Ljubešić, F. Klubička, Ž. Agić ...

  • Maceralni sastav i rang uglja Ibarskog basena

    Željana Novković, Nevena Andrić -Tomašević, Vladimir Simić, Dragana Životić (2022)
    Donjemiocenski ugljonosni Ibarski basen se nalazi u južnoj Srbiji. Intramontanski ektenzivni basen, izdužen u pravcu severozapad-jugoistok ispunjen je slatkovodnim sedimentima koji su formirani kao deo Dinarskog neogenog jezerskog sistema. Paleoreljef basena izgrađen je od paleozojskih amfibolskih škriljaca, sericit-hloritskih škriljaca, krečnjaka, mermera i metabazičnih stena, mezozojskih peščara, laporca, laporovitih krečnjaka, krečnjaka, dolomita, ofiolita i oligo-/miocenskih magmatskih stena. Tercijarne magmatske stene izgrađene su od oligocenskih dacito-andezita i neogenih kvarctlatita/riodacita i piroklastičnih stena. Miocenski sedimenti izgrađeni su od aluvijalnih breča, konglomerata, peščara, ...
    ugalj, macerali, refleksija vitrinita, Ibarski basen

  • An oilfield in Libya: A new model to enhance waste water disposal

    Dušan Danilović, Vesna Karović Maričić, Nori Elhaddad, Branko Leković (2016)
    нафта, лежишне воде, припрема

  • Productivity improvement with use of beam gas compressor: pilot test in Southeastern Europe mature field

    Bojan Martinović, Dušan Danilović, Branko Grubač, Robert Fadiga (2022)
    Most of the wells in the oilfield Turija are operating with sucker rod pumps, where casing pressure at around 15 bar, and with marginal production rates. The high value of casing pressure indicates high pressure on the face of the formation and depends directly on well productivity. In addition, with increasing value of the casing pressure gas column in the annulus is moving the dynamic fluid level near pump intake and more gas is entering the pump, it results ...
    beam gas compressor, BGC, increase productivity, sucker rod pump, SRP, mature field, artificial lift, production optimisation