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Упит dcterms_subject_txt:working environment

453 items

  • Application of machine learning for diagnosing the operation of a deep well pump in oil production

    Maja Trikić (2024)
    This paper will thoroughly examine how machine learning can improve the diagnosis of deep well pumps by analyzing the role and function of the pumps, dynamograms, sensor technologies, and diagnostic methods.Our analysis will provide insights into modern techniques and approaches for enhancing the performance and reliability of oil production systems, targeting cost reduction and increased operational efficiency.
    deep well pump, dynamograms, machine learning, diagnostics of operating coditions,Random Forest, XGBoost
    ... J. Pet. Sci. Eng. 2019 13. Cheng, H.; Yu, H.; Zeng, P.; Osipov, E.; Li, S.; Vyatkin, V. Automatic Recognition of Sucker-Rod Pumping System Working Conditions Using Dynamometer Cards with Transfer Learning and SVM. Sensors 2020. 14. Ren, T.; Kang, X.; Sun, W.; Song, H. Study of dynamometer ...
    ... repair or maintenance. 23 • Monitoring and Updating a.Performance Monitoring - Continuous monitoring of the model's performance in the real environment to ensure it remains accurate and relevant. b.Model Updating - Regularly updating the model with new data to reflect changes in pump operation ...
    ... diagnostic accuracy and reduce data collection and labeling costs. 4. Reinforcement Learning- The model learns through interaction with the environment and receiving rewards or penalties based on its decisions. The goal is to maximize total reward through a series of actions. For example, training ...

  • Fuzzy stohastički model izbora sistema otvaranja podzemnog rudnika

    Saša M. Jovanović (2016-05-16)
    Investiciono okruženje skopčano sa rudarskom industrijom je veoma svojstveno kada seuporedi sa okruženjima koje susrećemo u tipičnim proizvodnim industrijama. Neke odkarakterisitka rudarstva, koje su često naznačene kao jedinstvene su: visok intenzitetinvesticija, dugi predproizvodni periodi, visok rizik i neobnovljivost resursa.Investiranje u sistem otvaranja rudnika predstavlja dobar primer ireverzibilneinvesticije. Takva investicija zahteva pažljivu analizu, jer nakon njene realizacije ona sene može nadoknaditi bez značajnog gubitka vrednosti. Očigledno je da izbor sistemaotvaranja podzemnog rudnika pripada strateškom planiranju...
    otkopavanje; otvaranje; mreže i grafovi; fuzzy skupovi; stohastičkiprocesi; indeks konveksnosti; sistemi podrške odlučivanju
    ... STOCHASTIC MODEL OF UNDERGROUND MINE DEVELOPMENT SYSTEM SELECTION Abstract The investment environment associated with the mining industry is unique when compared with the environment encountered by typical manufacturing industries. Some of the characteristics of mining which are often ...

  • Using Lexical Resources for Irony and Sarcasm Classification

    Miljana Mladenović, Cvetana Krstev, Jelena Mitrović, Ranka Stanković (2017)
    The paper presents a language dependent model for classification of statements into ironic and non-ironic. The model uses various language resources: morphological dictionaries, sentiment lexicon, lexicon of markers and a WordNet based ontology. This approach uses various features: antonymous pairs obtained using the reasoning rules over the Serbian WordNet ontology (R), antonymous pairs in which one member has positive sentiment polarity (PPR), polarity of positive sentiment words (PSP), ordered sequence of sentiment tags (OSA), Part-of-Speech tags of words (POS) ...
    ... considered reliable, and the agreements whose values are α ≥ 0.8 can be considered very reliable. Inter-annotator agreement between two annotators working on annotation of ironic tweets can be con- sidered reliable in our case, as the value we obtained measured at α = 0.759. Verbal irony is a figure ...
    ... 9We used the following software tools in this paper: Developing tool Eclipse Java EE IDE Luna and Apache Jena open source software development environment which allows for reasoning at the level of OWL 2 language by converting OWL rules into the Jena rules format. "[rule5: (?a swn:bee_in_state ?b) ...

  • Application of stochastic models for mine planning and coal quality control

    Dejan Stevanović, Božo Kolonja, Ranka Stanković, Dinko Knežević, Mirjana Banković (2014)
    ... be made is which working benches should be mined. A decision variable (1) represents the i-th working bench and takes on a value of either zero (0) or one (1): X i i th th i if working bench if working bench is not m � 1 0 ined � � � (1) with Xi denoting the i-th working coal bench whose ...
    ... decision to be made is which working benches should be mined. A decision variable (1) represents the i-th working bench and takes on a value of either zero (0) or one (1): x. -{ if i” working bench 1 (1) 0 if i” working bench is not mined with X, denoting the i-th working coal bench whose predicted ...
    ... coals from different working benches within the single mine or even more mines are therefore becoming mandatory not only from an economic standpoint but also from the necessity of meeting emission require- ments. At the surface mine, coal is extracted from various active working benches and then t ...

  • Development of terminological resources for expert knowledge: a case study in mining

    Ljiljana Kolonja, Ranka Stanković, Ivan Obradović, Olivera Kitanović, Aleksandar Cvjetić (2015)

  • Asbestos-Based Pottery from Corsica: The First Fiber-Reinforced Ceramic Matrix Composite

    Philippe Colomban, Aleksandar Kremenović (2020)
    Asbestos-containing pottery shards collected in the northeast of Corsica (Cap Corse) and dating from the 19th century, or earlier, have been analyzed by SEM-EDS, XRPD, FTIR and Raman microspectroscopy. Blue (crocidolite) and white (chrysotile) asbestos fiber bundles are observed in cross-sections. Most of the asbestos is partly or totally dehydroxylated, and some transformation to forsterite is observed to occur, indicative of a firing above 800 C. Examination of freshly fractured pieces shows a nonbrittle fracture with fiber pull-out, consistent with ...
    asbestos, CMC, Corsica, fiber, pottery
    ... HR800 LabRam spectrometer (Horiba Scientific Jobin Yvon, Longjumeau, France) coupled to a BX Olympus microscope with different long and short working distance objectives, equipped with an Ar? ion laser (457 nm) and a Peltier cooled CCD detector (resolution <2 cm!), and (ii) a high-sensitivity LabRam ...
    ... 633 nm lasers and a similarly cooled CCD detector (resolution ~4 cm !). The analysis was carried out with Olympus x10, x50 and x100 ultralong, working distance objectives in order to obtain a characterization of the main phases. More than 20 spectra were collected for each sample with the two i ...
    ... Hulthen, B. On ceramic ware in northern scandinavia during the neolithic, bronze, and early iron Age: A ceramic-ecological study. In Archaeology and Environment Series (e-book), 8th ed.; University of Umea: Umea, Sweden, 1991. Kakoulli, L.; Prikhodko, S.V.; King, A.; Fischer, C. Earliest evidence for ...

  • Hydrochemical changes and groundwater grouping data by multivariate statistical methods within one karst system: recharge–discharge zone (Eastern Serbia case study)

    Ljiljana Vasić, Dragana Živojinović, Vladana Rajaković-Ognjanović (2020)
    Geochemistry and Petrology

  • Hidrotermalne alteracije kao kontrolni faktor mineralizacije u ležištu bakra Borska reka

    Jovana Mirčeta (2024)
    Rudno polje Bor kome pripada rudno telo Borska reka se nalazi u severnom delu Borsko- Srednjegorske zone Karpato-balkanske metalogenetske provincije. Ležište Borska Reka se nalazi u krajnjim severozapadnim delovima rudnog polja Bor. Smešteno je u intenzivno izmenjenim andezitima i njihovim piroklastitima. Relativno je jednostavne građe. Ležište Borska reka genetski pripada grupi hidrotermalnih ležišta, klasi porfirskih ležišta bakra i zlata. Sastavni je deo velikog hidrotermalnog rudonosnog sistema Bor, koji je po uslovima stvaranja i tipovima rudne mineralizacije sličan hidrotermalnom rudonosnom ...
    petrološka analiza, hidrotermalne alteracije, kontrolni faktor, porfirska ležišta
    ... RAW. > Biblioteka. Tabela najčešćih minerala hidrotermalnih izmena je prikazana u nastavku (Slika 10). Hydrothermal Minerals – Epithermal Environment - ~ II | | || | | i —— A d \ i J · J FOO ) V | \ I )] OE. i ž LO d —~ C | \ w \ r N \ _ ~O W:W}.š 1 \ z P a 0 | * V\ M_ ...

  • Hypogene speleogenesis related to porphyry magmatic intrusions and its influence on subsequent karst evolution in the Peruvian high Andes

    Alexander Klimchouk, David Evans, Sasa Milanovic, Cristian Bittencourt, Mauro Sanchez, F. Carlos Aguirre (2022)
    Earth-Surface Processes

  • Univerzitet u Beogradu Rudarsko-geološki fakultet Master rad Modeliranje disperzije prašine u životnoj sredini u fazi proširenja P.K. Veliki Krivelj

    Magdalena Milanović (2024)
    Modeliranje disperzije zagađenja životne sredine predstavlja proces u kom se korišćenjem matematičkih modela vrši simulacija širenja i raspodele zagađenja u životnoj sredini, koje nastaje određenim aktivnostima. Modeliranje nam pomaže da predvidimo zagađenja koja dobijamo planiranim aktivnostima u zemljištu, vodi i/ili atmosferi određene regije, kako bi na vreme preduzeli odgovarajuće preventivne mere kojim se smanjuje ili upotpunosti eminiše uticaj na životnu sredinu i zdravlje ljudi. Glavni zadatak ovog rada je procena uticaja, projekta proširenja kopa Veliki Krivelj, na kvalitet vazduha. Rezultati koji ...
    Modeliranje disperzije zagađenja životne sredine, površinski kop Veliki Krivelj, AERMOD, zagađenje vazduha, disperzija prašine
    ... D., Nišić D., Cvjetić A., Sekulić Z., (2015), Monitoring u životnoj sredini, Rudarsko-geološki fakultet Univerziteta u Beogradu [9] European environment Agency, Air pollution, URL https://www.eca.curopa.cu/en/topics/in-depth/air-pollution [10] N. Lilić, A. Cvjetić, 2005., Zagađenje i zaštita vazduha ...
    ... Krivelj prema severozapadu, Rudarsko-geološki fakultet, Beograd [13] U.S. Environmental Protection Agency, https://www.epa.gov/ [14] European environment Agency, Sources and emissions of alir pollutants in Europe, URL https://www.eea.curopa.ceu/publications/air-quality-in-ecurope-2022/sources-and- ...

  • Енергетска безбедност Европске уније у светлу актуелне енергетске транзиције

    Бобан Павловић, Дејан Ивезић (2021)
    Енергетска стратегија Европске уније, која од 2015. године обухвата и циљеве у области климатских промена, тежи изградњи „енергетске уније” која потрошачима из ЕУ даје сигурну, приступачну, чисту и одрживу енергију. Енергетска политика ЕУ поставља пред себе амбициозне циљеве у погледу коришћења обновљивих извора – учешће од 32% до 2030. године. Овако опсежну и динамичну енергетску транзицију у Европи усложњава хетерогеност националних енергетских система у погледу структуре енергетског микса, нивоа увозне зависности, као и нивоа технолошког, друштвеног и економског ...
    енергетска безбедност, Европска унија, енергетски показатељи, природни гас, обновљиви извори енергије
    ... Београд, 2015. 17. Sovacool, B. K., Brown, M. A., “Competing Dimensions of Energy Security: An International Perspective”, Annual Review of Environment and Resources, 35, 2010, pp. 77–108. 18. Baumann, F., Energy Security as multidimensional concept, Research Group on European Affairs, 2008 ...

  • 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

  • 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 Требишњице
    ... multipurpose and water protection and environment protection in the region of the Eastern Herzegovina and Dubrovnik littoral. Therefore, in the river Trebišnjica catchment the principle of the harmonious relation of the society towards natural environment was born, and according to Stevanović (2011) ...
    ... systematisation and data processing. In order to research statistical connections between dissolved minerals in water and parameters of natural environment, Q-mode and R- mode of Hierarchical cluster analysis, Factor analysis has been used on data of 929 samples. Except the statistical calculations ...
    ... but the impact of the spring in Lastva is unsignificant. Chemical composition of the water in the river Trebišnjica catchment is a result of environment in which is formed, primarily lithological composition, rainfall regime and antropogenic impact. The most prevailing water type is Ca-HCO3, mainly ...

  • Arsenopirit iz rudnih ležišta Šumadijsko-kopaoničke oblasti: paregeneza, sastav i produkti oksidacije

    Ivana N. Jelić (2023)
    Arsenopirit, FeAsS je čest pratilac polimetaličnih orudnjenja Šumadijsko-kopaoničke oblasti. Jedan je od sulfida koji u najvećoj meri koncentriše zlato. Nepoželjan je u rudama jer njegovom oksidacijom na jalovištima može doći do oslobađanja arsena koji spada u elemente toksične za životnu sredinu. U okviru ovog doktorata sistematski su ispitivani arsenopiriti iz različitih stadijuma i tipova orudnjenja rudnih ležišta i mineralizacija Šumadijsko-kopaoničke oblasti (Rudnik, Sastavci, Trepča, Gokčanica – Drenjak i Rujak, Golijska reka i Jurija). Uzorci arsenopirita ispitivani su polarizacionom mikroskopijom ...
    arsenopirit, zlato, skorodit, Šumadijsko-kopaonička oblast, parageneza, zonarnost
    ... scorodite, FeAsOa x 2H»O. American Mineralogist, 70, 838-844. Drahota, P. and Filippi, M. (2009): Secondary arsenic minerals in the environment: A review. Environment International 35, 1243—1255. Fleet M. E., MacLean P. J., Barbier J. (1989): Oscillatory-zoned As-bearing pyrite from strata- bound ...
    ... wastes from abandoned tungsten and tin exploitations. Journal of Hazardous Materials, 186, 590—601. Murphy, T. D. (2015): Bismuth in the supergene environment. A Tesis. The University of Western Sydney. O'Day, P. A. (2006): Chemistry and Mineralogy of Arsenic. Elements, 2, 77-83. Oeser, M., Weyer ...
    ... Roussel C., Nćel, C., Bril, H. (2000): Minerals controlling arsenic and lead solubility in an abandoned gold mine tailings. Science of The Total Environment 263, 209-219. Salzsaueler, K. A., Sidenko, N. V., Sherriff, B. L. (2005): Arsenic mobility in alteration products of sulfide-rich arsenopyri ...

  • Српски језик у дигиталном добу -- The Serbian Language in the Digital Age

    Duško Vitas, Ljubomir Popović, Cvetana Krstev, Ivan Obradović, Gordana Pavlović-Lažetić, Mladen Stanojević (2012)
    Serbian language
    ... 33 земље (стр. 81), који сарађују research centres in 33 European countries (p. 81). са заинтересованим странама из сфера предузетни- META-NET is working with stakeholders from econ- штва, државних институција, привреде, истражи- omy (soware companies, technology providers and вачких организација, ...
    ... domain, and which would partly be adjusted to the spe- cific features of Serbian, was abandoned in 2010 as un- profitable. A certain number of SMEs is working on the enhancement of search services, albeit mainly for for- eign partners and for English. For research purposes, experiments have been per- formed ...
    ... a “behind the scenes” technology that forms a well- demarcated research area, which in practice needs to be embedded into a suitable application environment. Language technology applications often provide significant service functionalities behind the scenes of larger software systems. Text summarisation ...

  • Model za optimizaciju graničnog saržaja metala u rudi u funkciji dugoročnog planiranja površinskih kopova

    Daniel P. Kržanović (2016-06-14)
    Optimizacija graničnog sadržaja metala u rudi jedan je od osnovnih koraka u planiranju i dizajniranju površinskih kopova i ima za cilj postizanje maksimalne neto sadašnje vrednosti (NPV). Iz tog razloga, optimizacija graničnog sadržaja i danas je predmet mnogih istraživanja u rudarskoj nauci, sa ciljem rešavanja praktičnih problema u eksploataciji ležišta.Dugoročno planiranje eksploatacije na površinskim kopovima podrazumeva sagledavanje svih relevantih parametara i faktora (geologije rudnog ležišta, tehnologije proizvodnog procesa, kapaciteta otkopavanja i prerade, troškova, cena metala, iskorišćenja i dr) kako ...
    površinski kop, dugoročno planiranje, optimizacija graničnog sadržaja, maksimizacija neto sadašnje vrednosti (NPV).
    ... algorithm with stockpiling option for open pit mining operations of two economic minerals, International Journal of Mining, Reclamation and Environment, Vol. 19, no. 3, pp. 176–187. Asad, M.W.A., 2005b, Cut-off grade optimization algorithm for open pit mining operations with consideration of ...
    ... the grid search method to determine optimum cutoff grades of multiple metal deposits, International Journal of Surface Mining, Reclamation & Environment, 18 (1), pp. 60-78. Barber J., 2011, 2D and 3D models, Geovia white papers, dostupno na: [http://es.geovia.com/sites/default/files/whitepa ...
    ... l simulation algorithms for modeling orebody uncertainty in open-pit optimization. International Journal of Surface Mining Reclamation and Environment, Vol. 2, No. 4, pp. 173–179. Dimitrakopoulos, R.G., 2007, Evaluating mine plans under uncertainty: can the real options make a difference, Resource ...

  • Investigating distant effects of the Moesian promontory: Brittle tectonics along the western boundary of the Getic unit (East Serbia)

    Ana Mladenović, Milorad D. Antić, Branislav Trivić, Vladica Cvetković (2019)
    In this study, we report evidence for brittle deformation in a part of the Carpatho–Balkan orogen, which is explained in terms of effects of the rigid Moesian promontory of the European plate on fault kinematics in East Serbia. We focus on the westernmost part of the Getic Unit of the East Serbian Carpatho–Balkanides, i.e. the Gornjak–Ravanica Unit, located between two main thrusts that were repeatedly activated from Early Cretaceous to recent times. We combine a new data set on ...
    Getikum, Mezijska jedinica, Karpato-balkanski orogen, krte deformacije, Gornjačko-ravanička jedinica

  • Differently shaped nanocrystalline (Fe, Y)3O4 and its adsorption efficiency toward inorganic arsenic species

    Biljana P Dojčinović, Boštjan Jančar, Lotfi Bessais, Aleksandar Kremenović, Nataša P Jović-Jovičić, Predrag T Banković, Dalibor M Stanković, Miloš Ognjanović, Bratislav V Antić (2019)
    Herein we report effects of partial substitution of Fe3+ by Y3+ in magnetite (Fe3O4) on morphology and inorganic arsenic species adsorption efficiency of the Fe3−xYxO4 nanoparticles formed. The series of Fe3−xYxO4 (x=0.00, 0.042 and 0.084, labeled as Y00, Y05 and Y10, respectively) was synthesized using co-precipitation followed by microwave-hydrothermal treatment (MW) at 200°C. With increase of yttrium content(xvalue), both the morphological inhomogeneity of the samples and the fraction of spinel nanorods as compared to spinel pseudospherical particles increased. By ...
    microstructure, microwave-hydrothermal synthesis, adsorption, magnetic nanoparticles, arsenic

  • Developing Termbases for Expert Terminology under the TBX Standard

    https://dr.rgf.bg.ac.rs/s/repo/item-set/522 (2014)
    ... publicly available bilingual terminological resource, GeolISSTerm (http:// geoliss.mprrpp.gov.rs/term/), was developed at FMG for the Ministry of the Environment, Mining and Spatial Planning of the Republic of Serbia, in the form of a thesaurus for geological terms. GeolISSTerm now contains more than ✶✹ ...
    ... Processing Society, 2011. Ranka Stankovi¢, Ivan Obradovié, Olivera Kitanovi¢, and Ljiljana Kolonja. Build- ing Terminological Resources in an e-Learning Environment. In D. MiloSevi¢, ed- itor, Proceedings of the Third International Conference on e-Learning, eLearning- 2012, September 2012, Belgrade, Serbia, pages ...

  • Утечњени природни гас (УПГ) – технологија производње и регасификације

    Јована Милетић (2024)
    У овом раду истраживање је обухватило сагледавање карактеристика утечњеног природног гаса као извора енергије и његове улоге у савременој расподели потрошње енергије на глобалном и европском нивоу. Проучени су елементи тржишта утечњеног природног гаса, сектори коришћења, транс-портне руте и количине испорука. Сагледан је пут природног гаса од лежишта до корисника преко утечњавања и транспорта у резервоарима, са посебним акцентом на технологијама производње и регасификације. Објашњено је пречишћавање сировог природног гаса ради уласка у процес утечњавања, процеси утешњавања и настојања ...
    утечњени природни гас, технологија производње и рега- сификације, транспорт, директно коришћење УПГ-а, могућност коришћења УПГ-а у Србији
    ... body (2024). S/afistica! Review of Borld KEnergy. United Kingdom, London. ISSN: 2976-7857 . Trafigura, (2015.), PA717/74 YS TO LNG IMPORTS, 4 working paper for the European Commission.https://www.trafigura.com/media/dejn5ajm/2023_trafigura _ pathways_to Ing_imports.pdf, pristupljeno 7.9.2024 ...
    ... ocTaJIO - 0,% Ha(ra HyKJIcapHa eHeprHja — 34% 13% OOHOBJbHBH H3BOpH 17% rac 24%. Cauka 2.4 – EnepoemckKu u36opu y EY (European Environment 4gency, 2023) 3a onpebunBame MecTa yreupbeHor HpHpojiHor raca y HIOKpMBaMby CHecpreT- cKHX noTpeOa EV, kao H y cyryuajy r100aJtHOr HHBOA, IIOCMaTPa ...
    ... 16. EReprercku OumaHcu, 2022. https://www.stat.gov.rs/media/377439/bilans-prirodnog- gasa-2022.pdf mpuHcrynjbeHo 15.9.2024. 17. European Environment Agency (2023). EU energy mix. Danska, Kopenhagen. https://www.eea.curopa.cu/signals-archived/signals-2022/infographics/cu-energy- mix/view p ...