Претрага
171 items
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Status and tendencies under development and application of underground coal gasification-UCG
Podzemna gasifikacija uglja u Svetu poslednjih decenija doživljava znatnu ekspanziju u istraživanju i razvoju zbog uveliko iskorišćenih ležišta uglja i loših ekoloških efekata (pri sagorevanju u TE) na životnu okolinu. Srbija ima znatne rezerve uglja, a kada bi se za PGU koristile samo vanbilansne rezerve i otkopni ostaci bilansnih, jasno je kakvi bi bili ekonomski (a i energetski i ekološki) efekti. U radu su sagledane aktivnosti u Svetu na tom planu, pa smatramo da ima smisla i potrebe za primenu ove ...David Petrović, Lazar Kričak, Stefan Milanović, Jovan Marković, Nikola Simić. "Status and tendencies under development and application of underground coal gasification-UCG" in International Conference “Energy and Ecology Industry EEI2018”, Beograd : Akademija inženjerskih nauka Srbije (AINS) (2018)
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A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)
... 6th isolating layer Second coal bed 7th water - bearing layer Sands of the lower aquifer, good filtration characteristics 8th water - bearing layer Sands of the lower aquifer, poor filtration characteristics An aquifer’s water balance assessment involves the determination of input ...
... medium and hydrodynamic state of aquifer flow, - aquifer regime, which is determined by certain laws, phenomena and distribution of factors, - water balance components, - boundary conditions (inflow into and outflow from the model), and - initial conditions, determined by the piezometric head at a ...
... RISTIĆ-VAKANJAC, V. (2012) Groundwater balance, natural recharge and drainage zones at open pit mine „Polje E“ of Kolubara Coal Basin (Republic of Serbia). In: BAN, M., et al. (eds.) CD Proceedings of the 7th Conference on Sustainable Development of Energy Water and Environmental Systems. Ohrid, Republic ...Jelena Ratković, Dušan Polomčić, Dragoljub Bajić, Bojan Hajdin. "A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)" in Underground Mining Engineering no. 29, Belgrade : University of Belgrade - Faculty of mining and geology (2016): 43-54
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Review: Methodological approaches and research techniques for addressing construction and remediation problems in karst reservoirs
Saša Milanović, Ljiljana Vasić (2021)Saša Milanović, Ljiljana Vasić. "Review: Methodological approaches and research techniques for addressing construction and remediation problems in karst reservoirs" in Hydrogeology Journal, Springer Science and Business Media LLC (2021). https://doi.org/10.1007/s10040-020-02280-1
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Mathematical modeling to define catchment size and real evapotranspiration (case study: Andrića karst spring, Western Serbia)
Marina Čokorilo Ilić, Vesna Ristić Vakanjac, Dušan Polomčić, Dragoljub Bajić, Jelena Ratković, Bojan Hajdin (2018)Water resources in karst are extremely important sources of drinking water supply. The quality of groundwater formed in karst aquifers is generally high and in most cases only chlorination is required. However, from a hydrogeological perspective, these water resources are the least studied. Often only basic information is available on catchment size, groundwater reserves (dynamic and static, if any) and groundwater balance. Detailed hydrogeological investigations and long-term monitoring of karst spring discharges are needed to acquire such information. In ...Marina Čokorilo Ilić, Vesna Ristić Vakanjac, Dušan Polomčić, Dragoljub Bajić, Jelena Ratković, Bojan Hajdin. "Mathematical modeling to define catchment size and real evapotranspiration (case study: Andrića karst spring, Western Serbia)" in National Conference with international participation “Geosciences 2018”, Bulgarian Geological Sciety (2018)
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Strategic Environmental Assessment and the precautionary principle in the spatial planning of wind farms – European experience in Serbia
Spatial determination planning is at an initial and very sensitive step in the development of wind farms. On one hand, it is important to maximize the potential of wind in a particular area, and on the other hand, it is important to achieve environmental protection (including the human population and natural heritage) in the same space at the same time. With this in mind, it is important to balance all the requirements that are relevant for reaching the optimal ...Boško Josimović, Aleksandar Cvjetić, Danilo Furundžić. "Strategic Environmental Assessment and the precautionary principle in the spatial planning of wind farms – European experience in Serbia" in Renewable and Sustainable Energy Reviews, Elsevier BV (2021). https://doi.org/10.1016/j.rser.2020.110459
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Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example
Miloš Marjanović, Biljana Abolmasov, Igor Peshevski, James Reeves, Irena Georgievska. "Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example" in Understanding and Reducing Landslide Disaster Risk, Springer International Publishing (2020). https://doi.org/10.1007/978-3-030-60227-7_29
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Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans
Karst terrains cover some 30% of the Western Balkans, where rich karst aquifers represent the main source of potable water supply and ensure the development of local economies and tourism. In this “classical karst” region, there are also numerous sites or areas under different forms of protection—from those that are included in the UNESCO World Heritage list to natural monuments and landscapes that are protected by national legislation. In and around them are specific representatives of flora and fauna ...Zoran Stevanović, Aleksandra Maran Stevanović, Želimir Pekaš, Romeo Eftimi, Veljko Marinović. "Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans" in Carbonates and Evaporites, Springer Science and Business Media LLC (2021). https://doi.org/10.1007/s13146-021-00754-1
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Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans
Karst terrains cover some 30% of the Western Balkans, where rich karst aquifers represent the main source of potable water supply and ensure the development of local economies and tourism. In this “classical karst” region, there are also numerous sites or areas under different forms of protection—from those that are included in the UNESCO World Heritage list to natural monuments and landscapes that are protected by national legislation. In and around them are specific representatives of flora and fauna ...Zoran Stevanović, Aleksandra Maran Stevanović, Želimir Pekaš, Romeo Eftimi, Veljko Marinović. "Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans" in Carbonates and Evaporites, Springer Science and Business Media LLC (2022). https://doi.org/10.1007/s13146-021-00754-1
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Analiza uslova formiranja oticaja reke Resave (istočna Srbija)
Vesna Ristić Vakanjac, Marina Mitrašinović, Veljko Marinović, Saša Milanović, Ljiljana Vasić, Branislav Petrović, Petar Vojnović (2023)Reka Resava zbog veličine sliva i količine vode koju daje Velikoj Moravi predstavlja jednu od najznačajnijih njenih desnih pritoka. U okviru njenog sliva jasno se izdvajaju gornji, geomorfološki raznolik deo sliva, koji je uglavnom izgrađen od karbonatnih sedimenata, i donji deo koji pripada Velikomoravskom basenu. Proticaj reke Resave se beleži u profilima Manastir Manasija koji kontroliše gornji deo sliva u iznosu od 358 km2 i Svilajnac, koji se nalazi na oko 3.5 km pre njenog ušća i koji kontroliše ...Vesna Ristić Vakanjac, Marina Mitrašinović, Veljko Marinović, Saša Milanović, Ljiljana Vasić, Branislav Petrović, Petar Vojnović. "Analiza uslova formiranja oticaja reke Resave (istočna Srbija)" in Zbornik radova III Kongresa geologa Bosne i Hercegovine sa međunarodnim učešćem, Neum, 21-23.9.2023. , Ilidža : Udruženje/udruga geologa u Bosni i Hercegovini (2023)
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Numerical modeling of Selanac debris flow propagation using SPH code
The Selanac debris flow is a very huge event triggered after extreme rainfall caused by Cyclone Tamara activity in the Republic of Serbia in May 2014. The Selanac case study was already modelling in different programs using Voellmy rheology assumptions like RAMMS software. In this paper research are focusing particularly on the process of debris flowing from initiation zone to main deposition area using Geoflow SPH two-phase model considering frictional rheology law. Main rheological parameters are back-calculated using also ...... equations are discussed by Pastor et al. (2009) considering: A. balance of mass of the mixture—propagating along the slope and increasing due to bed entrainment—combined to the balance of linear momentum of pore water, B. the balance of linear momentum of the mixture, C. a kinetic relation between ...
... avoided. The SPH model proposed by Pastor et al. (2009), defines propagations of mass as mixture of soil and water particles with calculation of velocity. In addition, calculation of pore water pressures propagation is possible to be obtained using Finite Difference Method coupled with two- phase model ...
... mass as a single-phase continuum. The others are considering two phases, solid and liquid, i.e. a granular skeleton with voids filled with either water or mud. If the shear resistance of the fluid phase can be neglected, the stress tensor in the mixture can be decomposed into a ‘pore pressure’ and ...Jelka Krušić, Biljana Abolmasov, Miloš Marjanović, Manuel Pastor, Saeid M. Tayyebi . "Numerical modeling of Selanac debris flow propagation using SPH code" in SCG-XIII International Symposium on Landslides. Cartagena, Colombia- February 22-26, 2021, International Society for Soil Mechanics And Geotechnical Engineering (2021)
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Karst wastewater as a high quality, renewable and within the circular economy water resource
Jovana Nikolić, Vesna Ristić Vakanjac (2021)High quality drinking water in it’s natural state is becoming less and less available to the human population. Based on the expected climate changes, it is considered that this resource will be less in the world but also in our region. Also, the accompanying polluting components that exceed the maximum allowable concentration are increasingly present in the waters. Even after the water treatment, it happens that some components are still in the drinking water, which adversely affects human health. ...Jovana Nikolić, Vesna Ristić Vakanjac. "Karst wastewater as a high quality, renewable and within the circular economy water resource" in Book of proceedings of the 3rd International Scientific Conference on vircular and bioeconomy CIBEK2021, Belgrade, Belgrade : School of Engineering Management (2021)
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Развој модела конструкције просторија отварања рудника са подземном експлоатацијом
Dražana M. Tošić (2016-08-26)Приликом израде подземних просторија у стјенској маси долази до нарушавања природне равнотеже напонских стања стијенског масива који су владали прије израде тих просторија, при чему долази до појаве прертасподјеле напона и његове концентрације у појединим правцима и тачкама, односно долази до појаве пластичних деформација које су праћене ломљењем стијенске масе и кретањима материјала према откопаном простору...модел, метод коначних елемената, просторија отварања, напон, дефеормација стијенског масива, алгоритам функционалних зависностиDražana M. Tošić. "Развој модела конструкције просторија отварања рудника са подземном експлоатацијом" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2016-08-26)
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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 ...... 1500 0500% |Ž 100 85.00 % – 0080bar |E i -50C -1000 o 100 200 300 400 Angle (degree) Peat GearBox Torque 2Nm Counter Balance Moment ? Nm Counter Balance EMect 1,967.8 kg Mehcmeter GRod 3,0,11,6 Pmone: (940) 767-4334 Far |940) 723-7507 E-Malt 4oGechometer com CopyrigPt 1594-2024 ...
... function of the formation volume factor, the oil formation volume factor Bo (m*/m*), and the water formation volume factor Bw (m?/m?): qo+qw 32 n qoBo+qwBw — qo - oil production, (m*/m*) — qw- water production, (m?/m?) If all the gas passes through the pump, the volumetric efficiency increases ...
... The horsehead consists of the following components: • Base with sturdy supports that must withstand at least twice the designed load. 27 • Balance Beam, which is mounted on the supports and designed for maximum expected loads. • Horsehead ("Horse Head"), which is connected to the smooth rod ...Ana Ponoćko. Design of a sucker rod pumping system, 2024
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Regionalna karakterizacija karstnih podzemnih voda dela centralnog Balkana u funkciji njihovog održivog korišćenja i menadžmenta
Veljko J. Marinović (2022)Karstne podzemne vode koristi oko 700 miliona ljudi na svetu, čime je njihov značaj za svetsko stanovništvo nemerljiv. U sklopu doktorske disertacije vršena su istraživanja i analize karstnih sistema dela centralnog Balkana (Srbije, Crne Gore i Savskog sliva Bosne i Hercegovine), kako bi se evaluirao ovaj dragoceni resurs. Analize su vršene na primerima karstnih sistema vrela Perućac, Seljašnica, Mokra i Mlava (Srbija), Oko Bijele i Rijeka Crnojevića (Crna Gora) i vrelo Bosne (Bosna i Hercegovina), kao i na regionalnom ...karstni sistem, podzemna voda, pritisci na kvantitet i kvalitet, menadžment podzemnih vodnih resursaVeljko J. Marinović. Regionalna karakterizacija karstnih podzemnih voda dela centralnog Balkana u funkciji njihovog održivog korišćenja i menadžmenta, Beograd : [V. Marinović], 2022
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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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Availability as a dimension of energy security in the Republic of Serbia
Boban Pavlović, Dejan Ivezić (2016)There is a range of modern approaches and models in literature for the evaluation and determination of energy security, which are based on different parameters and indicators. For most of them, a common characteristic is emphasizing the avail ability of energy, as an important dimension for ensuring energy security. In this paper, concise overview of Serbian energy sectors is given and appropriate energy indicators are defined and determined. Selected indicators provide insight into the main components that characterize availability ...... net imports and total available primary energy consumption (SOS1) within a given year [9]. For the purpose of this paper, data from the Energy Balance for 2014 are used: Pavlović, B., et al.: Availability as a Dimension of Energy Security in the Republic of Serbia THERMAL SCIENCE: Year 2017, Vol ...
... individual contribution of each component to the availability of energy, as a dimension of energy security in Serbia. Based on analysis of the Energy Balance of Serbia, Energy Sector Development Strat- egy of Serbia [9-15] and calculated indicators from this study, the initial pairwise comparison matrix ...
... Guidelines and Methodologies, 2005, International Atomic Energy Agency, http://www-pub.iaea.org/MTCD/publications/PDF/Pub1222_web.pdf [9] ***, Energy Balance of the Republic of Serbia in 2014 (in Serbian)., Statistical Office of the Republic of Serbia, http://webrzs.stat.gov.rs/WebSite/repository/docu ...Boban Pavlović, Dejan Ivezić. "Availability as a dimension of energy security in the Republic of Serbia" in Thermal Science, National Library of Serbia (2016). https://doi.org/10.2298/TSCI160923303P
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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... in the load on the smooth rod during a cycle are balanced using various methods, with the depicted equipment utilizing balance via counterweights on the main lever and balance beam. 2.1.2 Subsurface equipment for deep well pumping includes: a) Downhole pump b) Gas anchor c) Tubing anchor ...
... When additional data cannot be collected to balance the dataset, there are methods to adjust the dataset through sampling. There are two basic approaches: 1.Undersampling: In this method, only samples from the majority class are used to achieve a balance with the minority classes. 2.Oversampling: ...
... exceed the maximum load of the smooth rod), and the maximum stroke length of the smooth rod. Key structural components of the horsehead include the balance beam, the connecting rod (cam mechanism), the adjustment rod, counterweights, a gearbox, and a driving electric motor. The length of the adjustment ...Maja Trikić. Application of machine learning for diagnosing the operation of a deep well pump in oil production, 2024
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Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja
Ugljevi niskog ranga – ligniti u Republici Srbiji predstavljaju glavnu energetsku sirovinu koja se koristi za proizvodnju električne energije. Rudarstvo u Srbiji doprinosi bruto dodatoj vrednosti sa 1,8% (2020; https://publikacije.stat.gov.rs/). Sagorevanjem ugljeva niskog ranga u termoelektranama generišu se velike količine elektrofilterskog pepela i pepela, koje često predstavljaju jedan od izvora zagađenja životne sredine usled sadržaja toksičnih elemenata. Dalja upotreba produkata sagorevanja zavisi od njihovog sastava i sadržaja toksičnih mikroelemenata. Svakodnevno sagorevanje lignita u termoelektranama uslovljava konstantan monitoring potencijalno toksičnih ...Branko Kostić, Dejan Prelević, Sabina Kovač, Ksenija Eraković, Dragana Životić. "Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
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A contribution to the understanding of hydrochemical properties of thermomineral water on the L’dži locality (eastern part of North Macedonia)
Hristina Petrova, Katarzyna Wątor, Piotr Rusiniak, Boris Vakanjac, Vesna Ristić Vakanjac, Ewa Kmiecik (2023)Regarding the aspect of mineral, thermo-mineral, and thermal waters, on the territory of the Republic of North Macedonia, there are 65 registered locations, of which 8 are categorized as spas. This includes the Kežovica spa, also known as the Štipska spa. In the vicinity of Kežovica Spa is the thermo-mineral L’Dži spring with mineralization around 1.3 g/L and the water temperature at the time of sampling was 50.1 °C. Spring L’Dži is generated by a fault structure and is ...Hristina Petrova, Katarzyna Wątor, Piotr Rusiniak, Boris Vakanjac, Vesna Ristić Vakanjac, Ewa Kmiecik. "A contribution to the understanding of hydrochemical properties of thermomineral water on the L’dži locality (eastern part of North Macedonia)" in National Conference with International Participation “GEOSCIENCES 2023”, Review of the Bulgarian Geological Society, Sofia : Bulgarian Geological Society (2023)
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Multivariate Statistical Analysis of Hydrochemical and Microbiological Natural Tracers as a Tool for Understanding Karst Hydrodynamics (The Unica Springs, SW Slovenia)
Marina Ćuk Đurović, Metka Petrič, Igor Jemcov, Janez Mulec, Zdenka Mazej Grudnik, Cyril Mayaud, Matej Blatnik, Blaž Kogovšek, Nataša Ravbar (2022)Marina Ćuk Đurović, Metka Petrič, Igor Jemcov, Janez Mulec, Zdenka Mazej Grudnik, Cyril Mayaud, Matej Blatnik, Blaž Kogovšek, Nataša Ravbar. "Multivariate Statistical Analysis of Hydrochemical and Microbiological Natural Tracers as a Tool for Understanding Karst Hydrodynamics (The Unica Springs, SW Slovenia)" in Water Resources Research, American Geophysical Union (AGU) (2022). https://doi.org/10.1029/2021WR031831