Претрага
806 items
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A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers
Effectiveness evaluation is one of the basic components of engineering asset management and maintenance engineering in general. Effectiveness is an overall concept representing a measurement of quality of service level for the analyzed engineering system. This concept contains a series of partial indicators relating to time in operation and time for maintenance activities, as well as functional properties of the system. This article describes the analysis and structuring of partial indicators, as well as the development of a model ...Miloš Tanasijević, Predrag Jovančić, Dejan Ivezić, Uglješa Bugarić, Radiša Đurić. "A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers" in International Journal of Industrial Engineering: Theory, Applications and Practice (2019)
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Validation of vulnerability assessment by means of the Time Dependent, Model: case study from the Slovenian karst catchment
Groundwater vulnerability assessment methods are continuously being developed and existing methods are very often modified to provide better simulation of natural protection conditions and more objective results. Most frequently used methods are based on calculation of predefined parameters influencing water infiltration and underground flow, which can often lead to bias conclusions related to vulnerability evaluations. Some other methods, like the Time Dependent Model (TDM) are based on an approach, where parametrization is obtained at the final stage of the ...Ocena ranjivosti podzemnih voda, karstne podzemne vode, TDM metoda, delineacija sanitarnih zona, Slovenački karstVladimir Živanović, Nataša Ravbar, Igor Jemcov. "Validation of vulnerability assessment by means of the Time Dependent, Model: case study from the Slovenian karst catchment" in Proceedings of IAH2019, the 46th Annual Congress of the International Associaton of Hydrogeologists, Málaga (Spain), September 22-27, 2019, International Association of Hydrogeologists (IAH) (2019)
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Numerical modelling of the roughly simultaneous emplacement of two distinct ophiolite belts
Nikola Stanković, Vesna Cvetkov, Vladica Cvetković. "Numerical modelling of the roughly simultaneous emplacement of two distinct ophiolite belts" in 5th Congress Geologists of the Republic of North Macedonia, Ohrid, 28-29. 10. 2024, Македонско геолошко друштво (2024)
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Correlation of uniaxial compressive strength with the dynamic elastic modulus, p –wave velocity and s –wave velocity of different rock types
Knowing mechanical properties of rocks incorporated with ultrasonic waves velocities investigations provide a secure basis for mine modelling. Uniaxial compressive strength, dynamic elastic modulus and ultrasonic waves velocities are just some of the rock properties that indicate on presence of discontinuities, stratification and fissures of rocks. Determining the relationship of these rock properties testing the rock samples that are corresponding to different rock types extracted from different mineral deposits represents the core of this study. In this paper, we ...Jelena Majstorović, Miloš Gligorić, Suzana Lutovac, Milanka Negovanović, Luka Crnogorac. "Correlation of uniaxial compressive strength with the dynamic elastic modulus, p –wave velocity and s –wave velocity of different rock types" in Underground mining engineering, Рударско - геолошки факултет - Београд (2019)
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Развој модела употребног квалитета помоћне механизације на површинским коповима лигнита
Драгица Јагодић Крунић (2021)Тренутно стање помоћне механизације на површинским коповима лигнита је незадовољавајуће узроковано пре свега старошћу и неблаговременом заменом машима услед чега је расположивост недовољна а трошкови експлоатације и одржавања високи. Тренутно стање и захтеви који се постављају пред ове машине указују на неопходност оптимизације процеса управљања помоћном механизацијом. Одређивање оптималног времена замене и преосталих могућности је најодговорнији управљачки задатак који треба да буде заснован на свеобухватном сагледавању економских, техничких и других узрочно последичних веза. Са економског аспекта гледано треба одржавати ...помоћна механизација, употребни квалитет, ефективност, расположивост, сигурност функционисања, ризик, трошкови животног циклуса, фази логика, Монте Карло метода... системима: • Фактори поузданости; • Теорија фази логике. Модели подршке одлучивању код структуираних проблема Математички модели за подршку одлучивању: • Оптимизација и линеарно програмирање; • Табеле и стабла одлучивања; • Модели редова чекања; • Опште методе решавања проблема претраживањем ...
... коришћен у компанији, где су укључени трошкови електричне енергије, флуида и одржавања. Линеарни и променљиви фактори у моделима су анализирани у погледу расположивости и процене података, посебно са нагласком на одржавању. Концепт трошкова животног циклуса опреме даје смернице за анализу параметара рада ...
... Симулациони модели (Monte Karlo). Софтверска подршка одлучивању се користи као непосредна подршка одлучивању или за развој система за подршку одлучивању. Модели који имају добро развијену софтверску подршку су: • Оптимизациони модели; • Симулациони модели; • Предиктивни модели; • Модели машинског ...Драгица Јагодић Крунић. Развој модела употребног квалитета помоћне механизације на површинским коповима лигнита, Београд : [Д. Јагодић Крунић], 2021
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A tool for identifying the criticality in the disordered systems with metastable dynamics
Svetislav Mijatović, Dragutin Jovković, Sanja Janićević, Stefan Graovac, Đorđe Spasojević. "A tool for identifying the criticality in the disordered systems with metastable dynamics" in Physica A: Statistical Mechanics and its Applications, Elsevier BV (2021). https://doi.org/10.1016/j.physa.2021.125883
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Transition pathways of household heating in Serbia: Analysis based on an agent-based model
To explore pathways of the energy transition of household heating, an agent-based simulation model was developed for the case of the Serbian household sector. The model is focused on individual entities (households) with the objective to explore the effects of policy instruments on energy transition in households with individual heating systems. Empirically collected survey data were used as input for households’ attitudes towards sustainable heating. Simulations showed that the proposed instruments would lead to higher heating efficiency and less ...energetska tranzicija, modeliranje bazirano na agentima, sistemi grejanja, sektor domaćinstva, obnovljivi izvori energije, emisija CO2Boban Pavlović, Dejan Ivezić, Marija Živković. "Transition pathways of household heating in Serbia: Analysis based on an agent-based model" in Renewable and Sustainable Energy Reviews, Elsevier BV (2022). https://doi.org/10.1016/j.rser.2022.112506
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Dvodimenzionalna geometrijska morfometrija prvih gornjih molara hominina sa teritorije Srbije - taksonomska i metodološka analiza
Predrag N. Radović (2022)Primarni cilj ove studije tiče se taksonomske identifikacije fosilnih prvih gornjih molara (M1) hominina pronađenih u Srbiji, primenom metoda dvodimenzionalne (2D) geometrijske morfometrije. U prvoj (metodološkoj) fazi istraživanja ispitana je efikasnost 16 različitih pristupa (geometrijskih modela) u klasifikaciji M1 neandertalaca i anatomski modernog čoveka. Modeli su testirani na dva seta okluzalnih projekcija krunica (n = 34 i n = 64) dobijenih orijentisanjem digitalnih 3D modela u virtuelnom okruženju ili fotografisanjem fizičkih primeraka zuba. Prilikom testiranja primenjena je klasifikacija zasnovana ...2D geometrijska morfometrija, prvi gornji molar (M1), taksonomska identifikacija, neandertalci, anatomski moderni ljudi, Pešturina, Velika Balanica, SrbijaPredrag N. Radović. Dvodimenzionalna geometrijska morfometrija prvih gornjih molara hominina sa teritorije Srbije - taksonomska i metodološka analiza, Beograd : [P. Radović], 2022
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Analogue modelling of strain partitioning along a curved strike-slip fault system during backarc-convex orocline formation: Implications for the Cerna-Timok fault system of the Carpatho-Balkanides
Nemanja Krstekanić, Ernst Willingshofer, Taco Broerse, Liviu Matenco, Marinko Toljić, Uroš Stojadinović (2021)... deformation. 4.1. Reference model: model 1 Model 1 consists of a rigid indenter with rounded corners, while the surrounding, deformable material is entirely brittle (Table 1, Fig. 2a, e). Deformation results only from northward translation of the model layers. Model 1 (Fig. 3) documents the development ...
... (e.g., Kräutner and Krstić, 2003; Schmid et al., 2020). Note that the shear strain rate is Table 1 Model parameters. Model type: b - brittle only, b-v– brittle-viscous. Model number Model type Brittle layer thickness (cm) Viscous layer thickness (cm) Rigid block geometry Engine ...
... earlier deformation. 4. The reference model and parametrical study The results are described starting with a detailed analysis of a “reference model” (Model 1, Fig. 3), to which we compare the results of a parametric study (Figs. 4–7) and the best-fit model (Fig. 8). The latter serves to demonstrate ...Nemanja Krstekanić, Ernst Willingshofer, Taco Broerse, Liviu Matenco, Marinko Toljić, Uroš Stojadinović. "Analogue modelling of strain partitioning along a curved strike-slip fault system during backarc-convex orocline formation: Implications for the Cerna-Timok fault system of the Carpatho-Balkanides" in Journal of Structural Geology, Elsevier BV (2021). https://doi.org/10.1016/j.jsg.2021.104386
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Uticaj utiskivanja gas-lift gasa na prenos mase i toplote
Branko Grubač (2019)Nakon uvođenja kontinualnog gas-lifta, primećen je porast proizvodnje tečnog naftnog gasa, TNG, u postrojenju za preradu gasa, kao jednog od finalnih proizvoda dobijenog iz fluida gaso kondenzatnih i rastvorenog gasa iz naftnih bušotina. Pretpostavljeno je da se prisustvom gas-lift gasa uspostavlja drugačija ravnoteža faza u odnosu na slučaj bez gaslifta, te da je gas-lift gas stripovao propan i butane iz tečne u parnu fazu, što je dovelo do povećanja prinosa TNG-a. Napravljen je model bušotine koja radi u kontinualnom gas-liftu ...... Čang (Chung) modeli AEA i Čang modeli baziraju se na modelu Pedersona [92]. Za AEA model, izraz za konstantu fazne ravnoteže komponente i, (Ki) je: 𝑙𝑛 𝐾𝑖 = ∆𝐻𝑖 𝑓𝑅𝑇 (1 − 𝑇𝑇𝑖 𝑓) + ∆𝐶𝑝𝑅 [1 − 𝑇𝑖 𝑓𝑇 + 𝑙𝑛 𝑇𝑖 𝑓𝑇 ] + ∫ 𝑉𝑖𝐿 − 𝑉𝑖 𝑆𝑅𝑇 𝛿𝑃𝑃 0 6.2.39 AEA model je jedini ...
... su implementirani sledeći modeli: - Chung - Pederson - Conoco (Erikson) - AEA Navedeni modeli zahtevaju detaljno poznavanje sastava fluida. Modeli se zasnivaju na izračunavanju konstante fazne ravnoteže između čvrste i tečne faze. 6.2.7 Pederson (Pederson) model taloženja parafina Konstanta ...
... 6.2.6 Matematički modeli za procenu taloženja parafina u programu Aspen HYSYS .................... 74 6.2.7 Pederson (Pederson) model taloženja parafina .................................................................... 74 6.2.8 Konoko (Conoco) – Eriksonov (Erickson) model ................... ...Branko Grubač. Uticaj utiskivanja gas-lift gasa na prenos mase i toplote, Beograd : Rudarsko-geološki fakultet, 2019
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Critical disorder and critical magnetic field of the nonequilibrium athermal random-field Ising model in thin systems
Svetislav Mijatović, Dragutin Jovković, Sanja Janićević, Đorđe Spasojević. "Critical disorder and critical magnetic field of the nonequilibrium athermal random-field Ising model in thin systems" in Physical Review E, American Physical Society (APS) (2019). https://doi.org/10.1103/PhysRevE.100.032113
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Језички модели, шта је то?
Михаило Шкорић (2023)Михаило Шкорић. "Језички модели, шта је то?" in Језик данас, Нови Сад : Матица српска (2023)
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Modeliranje sistema upravljanja zaštitom životne sredine u rudarsko-energetskim kompleksima
Jelena R. Malenović - Nikolić (2016-07-12)Efikasnost funkcionisanja sistema upravljanja zaštitom životne sredine u rudarskoenergetskimkompleksima zavisi od stepena sprovođenja usvojene politike zaštiteživotne sredine i primene preventivnih mera zaštite životne sredine. Nedostatakfinansijskih sredstava za unapređivanje tehnologije eksploatacije, transporta, pripreme iprerade energetskih mineralnih sirovina u našim rudarsko-energetskim kompleksima,negativno utiče na ostvarivanje ciljeva zaštite životne sredine, a posledice radnihaktivnosti rudarsko-energetskih kompleksa dovode do smanjenja nivoa kvalitetavazduha, vode i zemljišta...rudarsko-energetski kompleks, životna sredina, sistem upravljanja,višekriterijumsko odlučivanje, modeliranje... rudarsko‐energetskim kompleksima 17 Model KIŠE je formiran za simulaciju regionalnog zagađenja vazduha, primenom postupaka linearnog programiranja i analize dinamičkih promena različitih strategija smanjenja zagađivanja vazduha [16]. Primenjuje se u svim evropskim zemljama, za praćenje ...
... neophodnost primene nuklearne energije i obnovljivih izvora energije. Linearnim funkcijama definiše se odnos troškova energetskog sistema, primene obnovljivih izvora energije i uštede energije u sektorima finalne potrošnje [26]. Model integrisane procene globalnih klimatskih promena MERGE, predviđen ...
... (IFS), model energetskog sistema Evropske unije (model prostih brojeva), model analize ulaza i izlaza (Input – output analiza), Azijsko-pacifički integrisani model (AIM), model za analizu primene Kjoto protokola (DNE 21 +), model integrisane procene globalnih klimatskih promena (MERGE), model analize ...Jelena R. Malenović - Nikolić. "Modeliranje sistema upravljanja zaštitom životne sredine u rudarsko-energetskim kompleksima" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2016-07-12)
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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... Geotehnički model Geotehničkim model predstavlјa osnovu za projektovanje nagiba kosina i sastoji se od četiri sastavna modela: - geološkog modela, - strukturnog modela, - modela stenskog masiva (svojstva stenskog materijala), - hidrogeološkog modela. Prikazani modeli takođe se ...
... Prikaz mrežnog modela ležišta 74 • Konturni model – posebno pogodan za prikazivanje planova koji se rade u dve dimenzije kao i za mrežni model kvaliteta izlaza koji zavisi od gustine same mreže (Slike 4.4.). Slika 4.4. - Konturni model • Žičani model – defineše prostorni ...
... seizmičnosti. 70 Slika 4.1. - Geotehnički model Geološki model Geološki model predstavlјa 3D prikaz geološke građe terena u zoni gde će biti formirane kosine površinskog kopa. Kategorije zastuplјenih materijala u modelu ne zavise samo od litološkog sastava nego i od vrste ...Branko M. Petrović. "Optimizacija dužine strele rotornih bagera u funkciji stabilnosti kosina i efektivnosti rada na površinskim kopovima lignita Srbije" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2016-07-12)
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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 ...... Unlike the conventional model, the final grade can be divided into several outcomes. The synthesis was made using the fuzzy theory and the AHP ranking model. The model is illustrated using the example of the bulldozer. Verification was made by comparing the results of the new model and the conventional ...
... intensity of the same. The model can be used as a simple tool in asset management in the sense of machine comparison and weak point analysis [18]. The model will be illustrated with the example of auxiliary machinery working in EPS (Electric Power Industry of Serbia) mines. The model will be verified by using ...
... synthesis model is represented through the fuzzy inference model where inputs are represented with fuzzificated estimates of partial indicators, and the rules of fuzzy composition are defined through outcomes that are corrected on the basis of ranks. 2.2.1. Fuzzy Inference in the Synthesis Model Availability ...Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović. "Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine" in Energies, MDPI AG (2019). https://doi.org/10.3390/en12214044
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Groundwater management by riverbank filtration and an infiltration channel, the case of Obrenovac, Serbia
Dušan Polomčić, Bojan Hajdin, Zoran Stevanović, Dragoljub Bajić, Katarina Hajdin. "Groundwater management by riverbank filtration and an infiltration channel, the case of Obrenovac, Serbia" in Hydrogeology Journal, Berlin, Heidelberg : Springer, International Association of Hydrogeologists (2013). https://doi.org/10.1007/s10040-013-1025-9
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An intelligent hybrid system for surface coal mine safety analysis
Nikola Lilić, Ivan Obradović, Aleksandar Cvjetić. "An intelligent hybrid system for surface coal mine safety analysis" in Engineering Applications of Artificial Intelligence (2010)
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Serbian NER&Beyond: The Archaic and the Modern Intertwinned
U ovom radu predstavljamo srpski književni korpus koji se razvija pod okriljem COST Akcije „Distant Reading for European Literary History” CA16204. Koristeći ovaj korpus romana napisanih pre više od jednog veka, razvili smo i učinili javno dostupnim Sistem za prepoznavanje imenovanih entiteta (NER) obučen da prepozna 7 različitih tipova imenovanih entiteta, sa konvolucionom neuronskom mrežom (CNN), koja ima F1 rezultat od ≈91% na test skupu podataka. Ovaj model je dalje ocenjen na posebnom skupu podataka za evaluaciju. Završavamo poređenje ...... al Neural Ne- twork (CNN) architecture, having F1 score of ≈91% on the test dataset. This model has been further assessed on a separate eva- luation dataset. We wrap up with compa- rison of the developed model with the exi- sting one, followed by a discussion of pros and cons of the both models. 1 ...
... places (LOC), events (EVENT) and organizations (ORG).8 4 SrpCNNER Model for Serbian In this section we first explain how we have turned the SrpELTeC corpus into a dataset for NER. Afterwards, we describe the training of the NER model SrpCNNER, followed by a detailed evaluation. Web users can naviga- ...
... naviga- te to http://ner.jerteh.rs/ in order to apply the SrpCNNER model directly on input text. The model can also be applied to a custom- size collection of text files using the previously mentioned NER&Beyond web platform. story), https://zenodo.org/communities/eltec 7 SrpELTeC, https://distantreading ...Branislava Šandrih Todorović, Cvetana Krstev, Ranka Stanković, Milica Ikonić Nešić. "Serbian NER&Beyond: The Archaic and the Modern Intertwinned" in Proceedings of the Conference Recent Advances in Natural Language Processing - Deep Learning for Natural Language Processing Methods and Applications, INCOMA Ltd. Shoumen, BULGARIA (2021). https://doi.org/10.26615/978-954-452-072-4_141
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VENTEX: An Expert System for Mine Ventilation Systems Analysis
Analiza sistema za ventilaciju je komleksan proces, koji bazira na proračunu brojnih parametara, koji se odnose na: stanje mreže, provetrenost, stabilnost sistema, gubitke vazduha, klimatske uslove, gasno stanje, ugroženost od požara i opasne prašine. Navedeni problemi se uspešno rešavaju paketom SimVent, ali potpuno razumevanje i korišćenje dobijenih rezultata zahteva angažovanje iskusnog specijaliste iz oblasti ventilacije. Rešenje je nađeno u kreiranju ekspertnog sistema VENTEX, čija je baza znanja formalizacija ekspertskog znanja iz oblasti ventilacije rudnika. U radu je prikazana metodologija ...... in OOA model Figure 1. Modified Coad-Yourdon object The strategy for evaluation of the general ventilation state of the mine is formally represented using a modification of the Coad- Yourdon object-oriented analysis (OOA) model (Coad and Yourdon, 1991). In the classical model every real ...
... knowledge, this model was modified by including a new (fourth) element, featuring the production (IF-THEN) rules related to an object in the model /Fig. 1/. Thus both the procedural and declarative knowledge related to a class object could be represented. Such a modified OOA model was the used ...
... can be either classes or instances within classes. The relationships among the objects in a model can be represented by linking them together into a hierarchical structure. Thus the modified OOA model based on the strategy for evaluation of the general ventilation state of the mine could be ...Ranka Stanković, Nikola Lilić, Ivan Obradović. "VENTEX: An Expert System for Mine Ventilation Systems Analysis" in YU Info '96 Brezovica, Društvo za informacione sisteme i računarske mreže (1996)
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Tectono-lithostratigraphic model of the Northern Banat Miocene sediments (Pannonian Basin, Serbia)
Dejan Radivojević, Ljupko Rundić (2017)... 04:22:03 Tectono-lithostratigraphic model of the Northern Banat Miocene sediments (Pannonian Basin, Serbia) Dejan Radivojević, Ljupko Rundić Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Tectono-lithostratigraphic model of the Northern Banat Miocene sediments ...
... is available at: www.dr.rgf.bg.ac.rs 53 7th International Workshop | Neogene of Central and South-Eastern Europe TECTONO-LITHOSTRATIGRAPHIC MODEL OF THE NORTHERN BANAT MIOCENE SEDIMENTS (PANNONIAN BASIN, SERBIA) Dejan Radivojević* & Ljupko Rundić University of Belgrade, Faculty of Mining ...
... MAGYAR et al., 2013). °e database consisted of numerous seismic data, both 2D and 3D, and exploration wells data allowed building of subsurface model of explored area. Special emphasis was placed on the Miocene sediments which are the most valuable part of sedimentary cover due to its economic ...Dejan Radivojević, Ljupko Rundić. "Tectono-lithostratigraphic model of the Northern Banat Miocene sediments (Pannonian Basin, Serbia)" in 7th International Workshop: Neogene of Central and South-Eastern Europe, Velika, Croatia, maj 2017, Croatian Geological Society (2017)