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277 items
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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 ...... reservoir and well limitations; characteristics of production fluid; and surface infrastructure. All data were technical parameters; economic parameters were not considered [11–14]. Input parameters can be grouped into three groups: I. Characteristics of reservoir, well and fluid (depth, pressure, production ...
... direction and j in a circular direction. Each of the five commonly used methods (GL, ESP, SRP, HP, PCP) defines a specific surface that is standard. The level of overlapping the surface, which represents the result for the new well and some of the standard surfaces, represents the level of applicability ...
... direction and j in a circular direction. Each of the five commonly used methods (GL, ESP, SRP, HP, PCP) defines a specific surface that is standard. The level of overlapping the surface, which represents the result for the new well and some of the standard surfaces, represents the level of applicability ...Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković. "Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic" in Energies, MDPI AG (2020)
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Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete
Milan Kragović, Nenad Ristić , Jelena Gulicovski, Andrijana Nedeljković, Snežana Pašalić, Ivica Ristović, Marija Stojmenović (2021)sagorevanje lignita, otpadna šljaka, zamena cementa, proizvodnja maltera i betona, fizičko-mehanička i fizičko-hemijska karakterizacija... spectrum of the hardened mortar sample, only spectral bands of the main constituents detected by the XRD are visible. The spectral bands of the new functional groups, as well as bands of other constituents, are not visible which may be explained with overlapping spectral bands or what may be an indication that ...
... of the prisms having dimensions 40 mm × 40 mm × 160 mm. Prisms were firstly dried at a temperature of 60 ± 5 ◦C to the constant mass (M0). Then the surface of the prism failure was set on the linear supports in a deep vessel, where water was poured so that the prism was immersed by 5 to 10 mm. Prior to ...
... to a concrete substrate was calculated according to the following formula: fu = F A (4) where F was the failure force at pull-off and A was the surface area of the dolly. 2.3.2. Tests of Physical–mechanical Properties of Concrete Samples Consistency–slump test was performed in accordance with standard ...Milan Kragović, Nenad Ristić , Jelena Gulicovski, Andrijana Nedeljković, Snežana Pašalić, Ivica Ristović, Marija Stojmenović . "Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete" in Minerals, MDPI (2021). https://doi.org/10.3390/min11090925
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Clockwise vertical-axis rotation in the West Vardar zone of Serbia: Tectonic implications
The Vardar-Tethyan mega-suture between the Eurasian and Adria (Gondwana) margins comprises remnants of oceanic lithosphere of Neotethys and distal parts of the adjacent continental margins including unconformable Late Cretaceous sedimentary cover and Cenozoic igneous rocks of post-obduction age. This study provides kinematic constraints for displacements and rotations affecting the Serbian part of the West Vardar and Jadar-Kopaonik units after the closure of the Neotethyan (= Sava) Ocean. The targets of the paleomagnetic research were Late Cretaceous sediments representing an ...... Pécskay 1999; Prelević et al. 2000; Jovanović 2003; Cvetković et al. 2004, 2007, 2013, 2016b; Prelević et al. 2005) they can be divided in three groups (for details see chapter ,,Paleo- magnetic sampling‘‘). The Neogene infill within the research area is represented by fresh water and brackish sediments ...
... and Pécskay 1999; Prelevié et al. 2000; Jovanovié 2003; Cvetkovié et al. 2004, 2007, 2013, 2016b; Prelevicé et al. 2005) they can be divided in three groups (for details see chapter ,,Paleo- magnetic sampling“). The Neogene infill within the research area is represented by fresh water and brackish sediments ...
... thermal (MMTD80, Magnetic Measurements, Aughton, and TSD- 1, Schonstedt Instrument Company, Reston) method. The remaining samples from the respective groups were demagnetized with the more efficient method, and in as Clockwise vertical-axis rotation in the West Vardar zone of Serbia: tectonic implications ...Vesna Lesić, Emo Márton, Violeta Gajić, Dragana Jovanović, Vesna Cvetkov. "Clockwise vertical-axis rotation in the West Vardar zone of Serbia: Tectonic implications" in Swiss Journal of Geosciences, Basel : Springer International Publishing (2018). https://doi.org/10.1007/s00015-018-0321-8
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Application of geophysical and multispectral imagery data for predictive mapping of a complex geo-tectonic unit: a case study of the East Vardar Ophiolite Zone, North-Macedonia
... evaluation metrics for three groups of RF models with vary- ing numbers of trees. The results indicate that the RF model utilizing the completely balanced C dataset, despite hav- ing the least amount of data for model training compared to other input data groups, yields the best overall outcomes ...
... created using conventional geo- logical mapping methods i.e., surface mapping techniques. The utilization of RF and KNN algorithms presents the potential for predicting ophiolites that may not be noticeable at the terrain surface, specifically those which are situated in the subsurface and that ...
... great significance as it ena- bles an investigation into potential ophiolite sites that were not identified through surface mapping methodologies or are situated beneath the surface. In the context of data analysis in areas with dense vegetation, such as the EVZ region, it is possible that the ...Filip Arnaut, Dragana Đurić, Uroš Đurić, Mileva Samardžić-Petrović, Igor Peshevski. "Application of geophysical and multispectral imagery data for predictive mapping of a complex geo-tectonic unit: a case study of the East Vardar Ophiolite Zone, North-Macedonia" in Earth Science Informatics, Springer Science and Business Media LLC (2024). https://doi.org/10.1007/s12145-024-01243-4
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Reducing environmental impact caused by mining activities in limestone mines
Radmila Gaćina, Bojan Dimitrijević (2022)Mining and its related activities have always resulted in changes in the environment and these changes can vary from one area to another. As a result of mining, several types of changes can be distinguished: destruction of land and existing vegetation, changes in terrain topography, modification in air quality, changes in surface and groundwater quality, as well as change geotechnical conditions of the rock. Environmental impact of mining have been a public concern. There is widespread global interest in mining ...Radmila Gaćina, Bojan Dimitrijević. "Reducing environmental impact caused by mining activities in limestone mines" in Underground mining engineering , Belgrade : University of Belgrade - Faculty of Mining and Geology (2022)
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Influence of mono- and two-component organic modifiers on determination of lipophilicity of tetradentate Schiff bases
Ispitivani su uticaji primene mono- i dvokomponentnih organskih modifikatora na određivanje lipofilnosti 12 tetradentatnih Šifovih baza metodom reverzno-fazne tankoslojne hromatografije. Osnovni cilj je da se proceni tip interakcije između posmatranih jedinjenja i komponenti primenjenih hromatografskih sistema i uspostavi neki obrazac ponašanja kako bi se lakše izabrala kombinacija organskih modifikatora koji će simulirati interakciju u biološkim sistemima na osnovu činjenica da iste osnovne intermolekularne interakcije su odgovorne za ponašanje supstanci i u biološkom i u hromatografskom sistemu. Primenjeni organski modifikator ...Nikola Stevanović, Aleksandar Mijatović, Aleksandar Lolić, Mario Zlatović, Rada Baošić. "Influence of mono- and two-component organic modifiers on determination of lipophilicity of tetradentate Schiff bases" in Chemical Papers, Springer Science and Business Media LLC (2021). https://doi.org/10.1007/s11696-021-01884-5
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Failure Estimation of the Majdanpek Open Pit East Face Based on Inverse Velocity Model
The Majdanpek open pit mine south district is currently active mining prospect of copper ore exploitation in eastern Serbia. Its depth is approaching the termination depth and occurrences of large-scale instabilities and global instability of the final pit slope is possible. These can generate catastrophic mass movement inside an area that encloses a regional road route and the Pek River bed which is channelled along the outer contour of the pit. The displacements that were noted in early 2023, in the ...Miloš Marjanović, Stefan Milanović, Nikola Simić, Lazar Kričak. "Failure Estimation of the Majdanpek Open Pit East Face Based on Inverse Velocity Model" in Regional Symposium on Landslides in the Adriatic-Balkan Region, Belgrade, 15-18th May 2024, University of Belgrade, Faculty of Mining and Geology (2024). https://doi.org/10.18485/resylab.2024.6.ch46
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Knowledge and Rule-Based Diacritic Restoration in Serbian
In this paper we present a procedure for the restoration of diacritics in Serbian texts written using the degraded Latin alphabet. The procedure relies on the comprehensive lexical resources for Serbian: the morphological electronic dictionaries, the Corpus of Contemporary Serbian and local grammars. Dictionaries are used to identify possible candidates for the restoration, while the dataobtainedfromSrpKorandlocalgrammarsassistsinmakingadecisionbetween several candidates in cases of ambiguity. The evaluation results reveal that,dependingonthetext,accuracyrangesfrom95.03%to99.36%,whilethe precision (average 98.93%) is always higher than the recall (average 94.94%).... concept can comprise single words of different parts of speech, including ambiguous ones, and phrases that can be either idiomatic or compositional groups. Large rows of synonyms and term variants are collected to provide better recog- nition of concepts in texts. The concept-based approach seems to ...
... concepts, Proceedings of CLIB 2018 98 including musical styles, musical instruments, musicians, musical compositions, musical performances, musical groups and organizations: Adagio or Accordion or ... Jazz music or . . . Musician ... or Opera or . . . or Orchestra or . . . (etc.). Figure 5: The upper ...Cvetana Krstev, Ranka Stanković, Duško Vitas. "Knowledge and Rule-Based Diacritic Restoration in Serbian" in Proceedings of the Third International Conference Computational Linguistics in Bulgaria (CLIB 2018), May 27-29, 2018, Sofia, Bulgaria, Sofia : The Institute for Bulgarian Language Prof. Lyubomir Andreychin, Bulgarian Academy of Sciences (2018): 41-51
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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 ...Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić. "Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine" in SSRN Electronic Journal, Elsevier BV (2021). https://doi.org/10.2139/ssrn.3945617
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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)... daily contact with the machines. The survey questions were directed towards three groups of people: Surveillance technical staff (SS), maintenance staff (MS) and exploitation staff (ES). Each person in the three groups received eight questions in the survey which they were to answer using the grading ...
... The analysis of the undercarriage type (UT) implies that the dozers in question were caterpillar transport system dozers. They were divided into two groups: Dozers with the triangular type and dozers with the flat type. Priority was given to the triangular type (equal to moderate priority on Saaty scale) ...
... best) to evaluate each of the different types of dozers (alternatives). It should be mentioned that the questions were adapted to each of the mentioned groups of surveyed people. The basis for defining the questions was the definition of the proper functioning of the dozer as well as raising the level of ...Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović . "Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining" in Energies, MDPI (2019). https://doi.org/https://doi.org/10.3390/en12122245
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Sustainable Modularity Approach to Facilities Development Based on Geothermal Energy Potential
The study presented in this paper assessed the multidisciplinary approach of geothermal potential in the area of the most southeastern part of the Pannonian basin, focused on resources utilization. This study aims to present a method for the cascade use of geothermal energy as a source of thermal energy for space heating and cooling and as a resource for balneological purposes. Two particular sites were selected—one in a natural environment; the other within a small settlement. Geothermal resources come ...геотермална енергија, Панонски басен, геотермална каскада, енергетска ефикасност, бањски центри, балнеологија, биоклиматска архитектура, стратегије пасивног дизајнирања, модуларни објекти... ◦C • Indoor temperature—summer 26 ◦C • Occupancy—surface per person (all regimes) 30 m2/pers • Metabolic heat emission per person 80 W/pers • Metabolic heat emission per m2 2.7 W/m2 • Dissipated heat from appliances 30 W/m2 • Fresh air flow per surface area 1 (m3/h)/m2 • Fresh air flow per person 30 ...
... placement and interconnection of open-air features with built-up struc- tures was proposed through a holistic design approach, taking into consideration functional demands, passive design principles [32,44], and the advantages of the modular approach as described in the previous section. The design strategies ...
... execution and operation. The width i of intermediate open-air spaces O may vary in regard to the height of the neighbouring modules M (Figure 7) for functional and privacy requirements. Additional screens may be added for enhanced privacy and additional sun protection of intermediate open spaces. The modest ...Nataša Čuković-Ignjatović, Ana Vranješ, Dušan Ignjatović, Dejan Milenić, Olivera Krunić. "Sustainable Modularity Approach to Facilities Development Based on Geothermal Energy Potential" in Applied Sciences-Basel, МDPI (2021). https://doi.org/10.3390/app11062691
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The effect of finite driving rate on avalanche distributions
Statistics, Probability and Uncertainty,Statistics and Probability,Statistical and Nonlinear PhysicsSonja Radić, Sanja Janićević, Dragutin Jovković, Đorđe Spasojević. "The effect of finite driving rate on avalanche distributions" in Journal of Statistical Mechanics: Theory and Experiment, IOP Publishing (2021). https://doi.org/10.1088/1742-5468/ac1f12
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Intrinsic groundwater vulnerability assessment by multiparameter methods, a case study of Suva Planina Mountain (SE Serbia)
Branislav Petrović (2020)Branislav Petrović. "Intrinsic groundwater vulnerability assessment by multiparameter methods, a case study of Suva Planina Mountain (SE Serbia)" in Environmental Earth Sciences, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s12665-020-8825-8
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Karstification depth and storativity as main factors of karst aquifer regimes: some examples from southern Alpine branches (SE Europe and Middle East)
Zoran Stevanović, Vesna Ristić-Vakanjac, Saša Milanović, Ljiljana Vasić, Branislav Petrović, Marina Čokorilo-Ilić (2015)Zoran Stevanović, Vesna Ristić-Vakanjac, Saša Milanović, Ljiljana Vasić, Branislav Petrović, Marina Čokorilo-Ilić. "Karstification depth and storativity as main factors of karst aquifer regimes: some examples from southern Alpine branches (SE Europe and Middle East)" in Environmental Earth Sciences, Springer Science and Business Media LLC (2015). https://doi.org/10.1007/s12665-015-4046-y
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Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling
Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary ChangeBranislav Petrović, Veljko Marinović, Zoran Stevanović. "Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling" in Environmental Earth Sciences, Springer Science and Business Media LLC (2023). https://doi.org/10.1007/s12665-023-10911-5
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Hydrochemical features and their controlling factors in the Kucaj-Beljanica Massif, Serbia
Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary ChangeFen Huang, Ljiljana Vasic, Xia Wu, Jianhua Cao, Saša Milanovic. "Hydrochemical features and their controlling factors in the Kucaj-Beljanica Massif, Serbia" in Environmental Earth Sciences, Springer Science and Business Media LLC (2019). https://doi.org/10.1007/s12665-019-8452-4
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Determination of the groundwater-leakage mechanism (binary mixing) in a karstic dam site using thermometry and isotope approach (HPP Visegrad, Bosnia, and Herzegovina)
Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary ChangeLjiljana Vasić, Saša Milanović, Anita Puskás-Preszner, Laszlo Palcsu. "Determination of the groundwater-leakage mechanism (binary mixing) in a karstic dam site using thermometry and isotope approach (HPP Visegrad, Bosnia, and Herzegovina)" in Environmental Earth Sciences, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s12665-020-08910-x
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Flood protection and water utilization of karst poljes: example of Gatačko Polje, Eastern Herzegovina
Tina Dašić, Ljiljana Vasić (2020)Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry,Global and Planetary ChangeTina Dašić, Ljiljana Vasić. "Flood protection and water utilization of karst poljes: example of Gatačko Polje, Eastern Herzegovina" in Environmental Earth Sciences, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s12665-020-08987-4
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3D modeling and monitoring of karst system as a base for its evaluation and utilization: a case study from eastern Serbia
Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary ChangeSaša Milanović, Zoran Stevanović, Ljiljana Vasić, Vesna Ristić-Vakanjac. "3D modeling and monitoring of karst system as a base for its evaluation and utilization: a case study from eastern Serbia" in Environmental Earth Sciences, Springer Science and Business Media LLC (2013). https://doi.org/10.1007/s12665-013-2591-9
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Predictive modeling for U and Th concentrations in mineral and thermal waters, Serbia
Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary ChangeMarina Ćuk Đurović, Igor Jemcov, Maja Todorović, Ana Mladenović, Petar Papić, Jana Štrbački. "Predictive modeling for U and Th concentrations in mineral and thermal waters, Serbia" in Environmental Earth Sciences, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s12665-020-09204-y