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Упит dcterms_subject_txt:stochastic modeling

250 items

  • Design of a sucker rod pumping system

    Ana Ponoćko (2024)
    For a long time in the history of oil production, sucker rod pumps have been the first and in many cases the only choice when it comes to mechanical extraction methods. Proper selection of each individual element of the system enables optimization, which entails benefits in the form of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The ...
    sucker rod pump, fluid production, mechanical extraction methods,, Prosper, QROD, RODSTAR
    ... study the effect of prime mover speed variation, stuffing box friction, etc. RODSTAR also allows you to combine sophisticated rod pumping system modeling with inflow performance data for even more powerful capabilities. There are two versions of RODSTAR: deviated and vertical. This manual applies ...

  • Elektromagnetska sprega sistema litosfera-atmosfera-jonosfera

    Aleksandra B. Kolarski (2016-08-25)
    Radio talasi vrlo niskih frekvencija VLF (eng. Very Low Frequency) frekventnog opsega od 3 do 30 kHz, koji se prostiru talasovodom Zemlja-jonosfera (50 -90 km) su, kao što je poznato, efikasni i nezamenljivi u osmatranju pojava u niskoj jonosferi, sa tla...
    prostiranje talasa vrlo niskih frekvencija, talasovod Zemlja-jonosfera, globalno električno kolo, atmosfersko električno pražnjenje, kratkotrajne svetlosne pojave
    ... poremećaja, zabeležene sistemima AbsPAL (Absolute Phase & Amplitude Logger) i AWESOME (Atmospheric Weather Electromagnetic Sistem for Observation Modeling and Education) u Beogradu, iskorišćene su za dijagnostiku niske jonosfere u regularnim i neregularnim solarno-terestričkim uslovima. Rezultati tih ...
    ... HALESIS projet: Hight Altitude Luminous Events Studied by Infrared Spectro-imagery. NASA Astrophysics Data System (ADS). Cummer, S. A. (2000). Modeling electromagnetic propagation in the earth-ionosphere waveguide. IEEE Transactions on Antennas and Propagation, 48(9), pp. 1420–1429. Cummer, S ...
    ... doi:10.1002/jgra.50460, Pasko, V. P. (2003). Electric jets. Nature, 423, pp. 927–929. Pasko, V. P., George, J. J. (2001). Three-dimensional modeling of blue jets and blue starters. EOS Trans. AGU - Fall Meet. Suppl., 82(47). Pasko, V. P., Inan, U. S., Bell, T. F., Reising, S. C. (1998). Mechanism ...

  • Vodosnabdevanje podzemnim vodama u Srbiji-stanje i perspektive

    Dušan Polomčić, Zoran Stevanović, Petar Dokmanović, Petar Papić, Vesna Ristić-Vakanjac, Bojan Hajdin, Saša Milanović, Dragoljub Bajić (2011)
    ... izvorištima opštine Kikinda. Rudarsko-geološki fakultet, Beograd 13. Milanović S., Stevanović Z., Vasić Lj., Ristić V., 2011: Monitoring and physical modeling of karst system as a base for its evaluation and utilization – A case study from eastern Serbia, Proceedings of 9th conference on Limestone hydrogeology ...

  • Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling

    Branislav Petrović, Veljko Marinović, Zoran Stevanović (2023)
    Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • A comparison between ARIMA, LSTM, ARIMA-LSTM and SSA for cross-border rail freight traffic forecasting: the case of Alpine-Western Balkan Rail Freight Corridor

    Miloš Milenković, Miloš Gligorić, Nebojša Bojović, Zoran Gligorić (2023)
    železnica, prekogranični teretni saobraćaj, ARIMA, LSTM, SSA

  • Adsorption and degradation of some psychiatric drugs by sol-gel synthesized titania-based photocatalysts: influence of tungsten and sodium content

    Nina L. Finčur, Maja J. Šćepanović, Mirjana Grujić-Brojčin, Biljana F. Abramović, Jugoslav B. Krstić, Aleksandar Kremenović, Tatjana Srećković, Aleksandar Golubović (2019)
    Mesoporous anatase nanopowders were doped with 0.05−0.5 mol% of W6, in order to obtain more efficient photocatalyst than TiO2 Degussa P25 in the degradation of amitriptyline (AMI) under simulated solar irradiation (SSI). Dominant XRPD peaks were ascribed to anatase phase, with additional peaks which could correspond to brookite, TiO2 bronze and sodium titanate, Na2Ti9O19. The Raman scattering measurements have confirmed anatase as dominant phase, with broad Raman feature at ~270 cm−1 possibly related to Ti–O–Na stretching vibration. All W-doped ...
    Sol-gel synthesis, Doped titania nanopowders, XRPD, Raman spectroscopy, Adsorption and photocatalytic degradation, Psychiatric drugs

  • Structural and geochronological constraints from the Drina-Ivanjica thrust sheet (Western Serbia): implications for the Cretaceous–Paleogene tectonics of the Internal Dinarides

    Kristof Porkoláb, Szilvia Kövér, Zsolt Benkó, Gabor Héja, Melinda Fialowski, Balázs Soós, Nataša Gerzina Spajić, Nevenka Đerić, László Fodor (2019)
    Internal Dinarides, Drina-Ivanjica thrust sheet, Deformation history, K–Ar dating, Obduction, Structural analysis
    ... anali balkanskoga poluostrva, 49, 11—160. Duretz, T., Agard, P., Yamato, P., Ducassou, C., Burov, E. B., & Gerya, T. V. (2016). Thermo-mechanical modeling of the obduction process based on the Oman ophiolite case. Gondwana Research, 32, 1—10. Ercegovac, M. (1975). Microspores of the older Paleozoic ...

  • Modeliranje buke u zoni površinskog kopa Ljubija ležišta Ciganuša - Škorac

    Teodora Kaličanin (2024)
    Svaki neželjeni zvuk u prirodi se može definisati kao buka. Buka svakodnevno utiče na ljude i predstavlja pretnju po ljudsko zdravalje. Zbog toga su nastale mnoge metode za merenje, proračun i saniranje ovog problema.Tema ovog završnog rada master studija je modeliranje buke u zoni površinskog kopa ''Ljubija''. Opisani su pojam buke i zvuka kao osnov za kasnije iznesene podatke, kao i tipovi i različiti izvori buke. Prikazane su metode merenja buke i uređaji koji se u tom procesu koriste. Obrađen ...
    buka, modeliranje, uticaj na čoveka, površinski kop
    ... Pollutant Inventory, Emission Estimation Technique Manual for Mining and Processing of Metallic Minerals, 2012. 17. EPA, Air Quality Dispersion Modeling - Preferred and Recommended Models, 2017 18. ISO 1996-2:2019 - Akustika — Opisivanje, merenje i ocenjivanje buke u životnoj sredini — Deo 2: ...

  • Mikroelementi u uljnim šejlovima Aleksinca i njihov uticaj na životnu sredinu

    Nikoleta Aleksić (2021)
    ... Gourich B., Chafi M., Stiriba Y., Vial Ch., Drogui P., Naja J., (2017). „Electrocoagulation process in water treatment: A review of electrocoagulation modeling approaches“, Desalination 404 [3] Segura S.G., Eibanda M. M. S.G., Vieira de Meloa J., Martínez-Huitlea C. A. (2017). „Electrocoagulation and ...
    ... marine sediment. Environmental Science & Technology 43, 3815–3823. 12. Cho, Y.M., Werner, D., Choi, Y., Luthy, R.G., 2012. Long-term monitoring and modeling of the mass transfer of polychlorinated biphenyls in sediment following pilot-scale in-situ amendment with activated carbon, Journal of Contaminant ...
    ... California, USA. Environmental Toxicology and Chemistry 26, 2143–2150. 18. Choi, Y., Cho, Y.M., Gala, W.R., Luthy, R.G., 2013, Measurement and modeling of activated carbon performance for the sequestration of parent-and alkylated-polycyclic aromatic hydrocarbons in petroleum-impacted sediments. ...

  • Optimizacija i planiranje površinskih kopova stohastičkim modelima

    Dejan R. Stevanović (2015-05-29)
    Savremeno rudarstvo izloženo je stalnom trendu pogoršanja uslova poslovanja.Mogućnost ostvarenja ekonomskih i drugih ciljeva rudarskog projektakompromitovana je stalnim pogoršanjem kvaliteta ležišta na kojima se vršieksploatacija, kao i značajnoj dozi neizvesnosti povezane sa geološkim,ekonomskim i tehničkim parametrima proizvodnje. U ovako kompleksnimuslovima poslovanja, matematički modeli sposobni da odgovore značajnimizazovima, odnosno ponude optimalna rešenja kojima se garantuje maksimalnoispunjenje projektovanih ciljeva, nameću se kao neophodnost.Trenutni, konvencionalni pristup optimizaciji i planiranju površinskih kopovazasniva se na algoritmima, razvijenim sredinom prošlog veka čije je opšteobeležje deterministički ...
    površinski kop, planiranje, optimizacija, stohastički modeli, kontrola kvaliteta uglja, neizvesnost.
    ... Exploring stochastic optimization in open pit mine design, Department of Mining and Materials Engineering, McGill University, Montreal Coombes J, 2004, Resource Estimation, Snowden Mining Industry Consultants Cowan E.J, Beatson R.K, Ross H.J., Fright W.R, 2003, Practical Implicit Geological Modeling, 5th ...
    ... Fundamentals of geostatistics in five lessons. Short course in geology, vol. 8., American Geophysical Union. Journel A, 1996, Modeling uncertainty and spatial dependence: Stochastic imaging, International Journal of Geographical Information Systems, Vol. 10, str. 517-522. K. Rezaie, M.S. Amalnik, A. Gereie ...
    ... and optimization of open pits, usage of stochastic mathematical models is analyzed in the research that is represented by this dissertation. The aim of the dissertation is to prove the advantages of implementations of stochastic or combined (hybrid) stochastic and deterministic approach over a purely ...

  • Hidrogeohemijska valorizacija esencijalnih mikroelemenata mineralnih voda Srbije

    Jana S. Stojković (2013-09-25)
    Mineralne vode još od davnina privlače pažnju ljudi i to kako u pogledu istraživanja iproučavanja, tako i u pogledu njihovog iskorišćavanja. Naročito je važno poznavanjesadržaja mikroelemenata u njima, jer su to komponente njihovog hemijskog sastavakoje ih odvajaju od tzv. „običnih“ malomineralizovanih voda.U ovom radu proučavani su odabrani esencijalni mikroelementi (fluor, bor, litijum,kalijum, stroncijum i silicijum), u mineralnim vodama Srbije, pri čemu je analiziranopreko 130 uzoraka mineralnih voda iz različitih geoloških sredina, to jest hidrogeološkihrejona. Cilj ovog istraživanja bio je ...
    esencijalni mikroelementi, faktori migracije, zakonomernosti rasprostranjenja, hidrogeohemijski procesi, multivarijantna statistička analiza, mineralne vode Srbije
    ... 10.0), spatial distribution of microelements in mineral waters of Serbia has been studied (software package Esri ArcGIS 9.3), and hydrochemical modeling has been applied on a certain number of mineral water samples (software package USGS PHREEQC 2.18). The use of factor analysis allowed grouping ...
    ... microelements concentrations to the limits recommended by domestic and foreign drinking water regulations and guidelines. Applying hydrochemical modeling on chosen mineral water samples the presence of the most probable ion species of the analyzed microelements has been calculated, closely defining ...

  • Ontološki model upravljanja rizikom u rudarstvu

    Olivera Kitanović (2021)
    Rudarska proizvodnja obuhvata kompleksne tehnološke sisteme, što nameće potrebu za uspostavljanjem i unapređivanjem sistema upravljanja rizikom. Heterogenost i obim podataka neophodnih za upravljanje rizikom zahtevaju sistem koji ih na fleksibilan način integriše i omogućava njihovo optimalno korišćenje. Osnovni cilj ove disertacije je razvoj ontologije za domen rudarstva i na njoj zasnovanog modela za upravljanje rizikom. Njegova realizacija podrazumeva i implementaciju algoritama ekstrakcije informacija za popunjavanje ontologije, kao i odgovarajuće softversko rešenje. Razvoj modela obuhvata i značajno proširenje rudarskog korpusa, kao ...
    rudarstvo, rizik, upravljanje rizikom, procena rizika, ontologija, semantička mreža, ekstrakcija informacija, upravljanje znanjem, računarska lingvistika
    ... methods for evaluation and interpretation of the obtained results. Information technology tools were used for model development: UML for concept modeling, OWL for ontology development, SWRL rules for inference mechanism, query languages CQL for corpus and SPARQL for ontology. The research results ...
    ... (Evert 2005). Tehnikama obrade prirodnog jezika su ekstrahovani kandidati za sadržaj ontologije, pronalaženjem veza između 1 UML (engl. Unified Modeling Language) je standardni jezik za vizuelno prikazivanje objektnog modela 5 imeničkih fraza iz domena rudarstva i njihovih kolokacija. Takođe ...
    ... de Textes Journalistiques.” PhD Thesis, Tours. Galatescu, Alexandra, Adriana Alexandru, Corneliu Zaharia, and Stefan Kovacs. 2010. “Ontology-Based Modeling and Inference for Occupational Risk Prevention.” In SEMAPRO 2010: The Fourth International Conference on Advances in Semantic Processing, 205–12 ...

  • Optimizacija utovarno-transportnih sistema u funkciji planiranja površinskog kopa

    Mirjana V. Banković (2018-07-13)
    Profitabilna eksploatacija sve složenijih ležišta je težak zadatak koji zavisi odtemeljnog procesa analize, planiranja i projektovanja rudnika. Izvodljiv strateškiplan mora da zadovoljava društvena, regulatorna, tehnološka, geometrijska iekonomska ograničenja. Kako bi se postigao osnovni cilj, odnosno profitabilnost iodrživost rudarskog projekta na duži period, neophodno je unapređenjematematičkih modela i informatičke podrške procesima planiranja i optimizacijekoji će omogućiti efikasnu realizaciju ovih ciljeva...
    tehnološki model, integralni model, planiranje, optimizacija,utovarno-transportni sistem, neto sadašnja vrednost projekta
    ... R. M., Knežević, D. N., Banković, M. V., 2014, Application of stochastic models for mine planning and coal quality control. Thermal Science, 18 (4), 1361-1372. Ta, C. H., Kresta, J. V., Forbes, J. F., Marquez, H. J., 2005, A stochastic optimization approach to mine truck allocation. International journal ...
    ... optimising production scheduling for open pit mine design. Mining Technology, 114 (1), 45-54. 202 Ramazan, S., Dimitrakopoulos, R., 2007, Stochastic optimisation of long-term production scheduling for open pit mines with a new integer programming formulation. Orebody Modelling and Strategic Mine ...
    ... Mining Machinery, 8-9 July 1999 Calcuta, India. Shishvan, M., Benndorf, J., 2014, Performance optimization of complex continuous mining system using stochastic simulation. Proceedings of Engineering Optimization 2014, the 4th Internationa Conference on Engineering Optimization, 2014. 273-278. Simonović ...

  • A Data Driven Approach for Raw Material Terminology

    Olivera Kitanović, Ranka Stanković, Aleksandra Tomašević, Mihailo Škorić, Ivan Babić, Ljiljana Kolonja (2021)
    The research presented in this paper aims at creating a bilingual (sr-en), easily searchable, hypertext, born-digital, corpus-based terminological database of raw material terminology for dictionary production. The approach is based on linking dictionaries related to the raw material domain, both digitally born and printed, into a lexicon structure, aligning terminology from different dictionaries as much as possible. This paper presents the main features of this approach, data used for compilation of the terminological database, the procedure by which it has ...
    sirovine, rudarstvo, terminologija, rečnik, terminološka aplikacija, mobilna aplikacija, digitizacija, leksički podaci, korpusi, otvoreni povezani podaci
    ... [57,58]). The Python script prepared in the form of a jupyter notebook was published at github [57]. Current work of the Ontolex group is focused on modeling word embeddings, collocations and similar words and we will add this feature when it becomes stable. An example of ontolex-lemon frequency and attestation ...

  • Prirodno prečišćavanje i stimulisana bioremedijacija podzemnih voda zagađenih naftnim ugljovodonicima

    Nenad M. Marić (2016-09-26)
    Disertacija se konceptualno sastoji iz dva dela kojima je obuhvaćen pasivan (prirodnoprečišćavanje) i aktivan remedijacioni pristup (stimulisana bioremedijacija) kodpodzemnih voda zagađenih naftnim ugljovodonicima.U prvom delu disertacije prikazani su rezultati osmatranja procesa prirodnogprečišćavanja u podzemnim vodama na lokaciji istorijskog zagađenja kerozinom.Tragovi zagađenja naftnim ugljovodonicima pronađeni su 20 godina nakon prosipanjakerozina. Ovo je stvorilo osnovu za proučavanje efekata dugotrajne izloženostipodzemnih voda procesima biodegradacije u terenskim uslovima. Uočeno je da sesnižene koncentracije elektron akceptora (O2, NO3-, SO42-) i povišene koncentracijemetaboličkih produkata biodegradacije ...
    podzemne vode, naftni ugljovodonici, kerozin, prirodno prečišćavanje,stimulisana bioremedijacija
    ... IM, Eganhouse RP, Siegel DI, Bennett PC (1993) Crude oil in a shallow sand and gravel aquifer-III. Biogeochemical reactions and mass balance modeling in anoxic groundwater. Appl Geochem 8, 569– 586. Nenad M. Marić ...
    ... JP, Chai EY, Colthart JD, Klein CL (1989) Aerobic biodegradation of beznene, toluene and xylene in a sandy aquifer: data analysis and computer modeling. Ground water, vol. 27, no. 6, 267-312. 30. Christensen T, Bjerg P, Banwart S, Jakobsen R, Heron G, Albrechtsen HJ (2000) Characterization of ...

  • Fuzzy Model for Risk Assessment of Machinery Failures

    Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković (2020)
    The main goal of this research was the development of an algorithm for the implementation of negative risk parameters in a synthesis model for a risk level assessment for a specific machine used in the mining industry. Fuzzy sets and fuzzy logic theory, in combination with statistical methods, were applied to analyze the time picture state of the observed machine. Fuzzy logic is presented through fuzzy proposition and a fuzzy composition module. Using these tools, the symmetric position of the ...
    fazi teorija, rizik, otkaz rudarskih mašina
    ... 110, 152–163. [CrossRef] 25. Vamvakas, P.; Tsiropoulou, E.E.; Papavassiliou, S. Dynamic spectrum management in 5G wireless networks: A real-life modeling approach. In Proceedings of the IEEE INFOCOM 2019—IEEE Conference on Computer Communications, Paris, France, 29 April–2 May 2019; pp. 2134–2142. ...

  • Процена ризика од загађивања водних ресурса под утицајем напуштених рударских радова на простору Србије

    Nebojša B. Atanacković (2018-08-31)
    Велики број напуштених рударских радова и ограничена средства за рекултивацијуи ремедијацију деградираних простора подстакле су развој метода за издвајањеприоритетних локација на које је потребно усмерити даља истраживања. У датомконтексту, у склопу израде дисертације спроведене су научно-истраживачкеактивности које су за предмет имале анализу утицаја значајнијих напуштенихрударских радова на водне ресурсе на простору Србије јужно од Саве и Дунава.Разматрање предметне проблематике извршено је кроз развој и примену семи-квантитативне методологије за анализу ризика од загађивања површинских иподземних вода на регионалној размери. Примењена ...
    анализа ризика, водни ресурси, водна тела, рудничке воде, рударскиотпад, аналитички хијерархијски процеси, кластер анализа, математичка теоријаатрибута, функције припадности, семи-квантитативне методе
    ... Pastorok A.R. et al., eds (2002) Ecological Modeling in Risk Assessment: Chemical Effects on Populations, Ecosystems, and Landscapes. Lewis Publishers 118. Pastorok A.R., Resit Akçakaya H., Regan H., Ferson S. and M. Bartell S. (2003) Role of Ecological Modeling in Risk Assessment. Human and Ecological ...
    ... загађивања водних ресурса модели су најчешће базирани на прорачуну транспорта и концентрације загађујућих супстанци (енгл. fate and transport modeling). Нумерички модели струјања подземних вода и транспорта загађујућих супстанци су нашли велику примену у пракси у области заштите подземних вода ...
    ... Београду, Рударско-геолошки факултет, Београд. 107. Nelson E., Mendoza G., Regetz J., Polasky S., Tallis H., Cameron D. R., ... Shaw M. R. (2009) Modeling multiple ecosystem services, biodiversity conservation, commodity production, and tradeoffs at landscape scales. Frontiers in Ecology and the E ...

  • Kontaktni metamorfizam gornjokrednih sedimentnih stena Rudnika

    Kostić N. Bojan (2021)
    Kontaktni metamorfizam gornjokrednih sedimentnih stena na planini Rudnik ispitivan je na uzorcima iz pet bušotina. Definisano je šest varijeteta krednih stena (protolita) koji čine dve litološke jedinice izgrađene od klastičnog, karbonatnog i klastično-karbonatnog materijala. Vulkanskom aktivnosti na Rudniku formirana su vulkanska tela koja se utiskuju duž slojevitosti sedimentnih stena, a neka ih presecaju u vidu dajkova. Starost ovog vulkanskog događaja određena je na 23.9 miliona godina. Ovaj miocenski vulkanizam doveo je do kontaktno metamorfnih promena sedimentnih stena i obrazovanja skarnova ...
    Rudnik, kontaktni metamorfizam, sedimentne stene, hornfels, skarn, granati, vezuvijan
    ... changes in conditions of contact metamorphism during garnet crystallization. According to pressure-temperature diagram based on thermobarometric modeling the temperature of 430±30° C and pressure up to 800 bars were inferred. During the first stage, i.e. prograde metamorphism formed garnet and pyroxene ...

  • Study of the Synergetic Effect of Co-Pyrolysis of Lignite and High-Density Polyethylene Aiming to Improve Utilization of Low-Rank Coal

    Ivan Kojić, Achim Bechtel, Nikoleta Aleksić, Dragana Životić, Snežana Trifunović, Gordana Gajica, Ksenija Stojanović (2021)
    Polimeri i plastika, opšta hemija
    ... plastics mixtures. Int. J. Hydrogen Energy 2011, 36, 9014–9022. [CrossRef] 40. Kathiravale, S.; Yunus, M.N.M.; Sopian, K.; Samsuddin, A.; Rahman, R. Modeling the heating value of municipal solid waste. Fuel 2003, 82, 1119–1125. [CrossRef] 41. Han, J.; Yao, X.; Zhan, Y.; Oh, S.Y.; Kim, L.H.; Kim, H.J. A ...

  • 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
    ... factors, some of which are measurable and belong to the class of deterministic (static) loads, 11 while the majority of dynamic loads are stochastic in nature and often cannot be precisely quantified. This results in irregular and unpredictable load function shapes, affecting the generation ...
    ... useful information as possible. Applied in: a.Data Visualization - Using methods like Principal Component Analysis (PCA) or t- Distributed Stochastic Neighbor Embedding (t-SNE), you can visualize high- dimensional data in 2D or 3D space. This can help in identifying patterns in the data that ...
    ... used to predict numerical values such as vibration levels or pressure that may indicate the pump's condition. b.Polynomial Regression - Used for modeling complex relationships between variables, which can help in predicting complex patterns in pump behavior. • ModelTraining a.Training - The model ...