Претрага
98 items
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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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Примена ауторегресионих модела за потребе краткорочних прогноза истицања карстних врела
Вељко Мариновић, Весна Ристић Вакањац, Саша Милановић, Љиљана Васић, Бранислав Петровић, Душан Поломчић, Радисав Голубовић (2023)Модел вишеструке линеарне регресије је најчешће примењивани модел за симулације, односно прогнозе одговарајућих случајно променљивих величина. Као најједноставнији модели примењују се ауторегресиони (АР) модели који симулирају истицање карстних врела на основу издашности врела регистрованих претходних дана. АР модели примењени су на примерима Великог врела за шестогодишње периоде осматрања, односно врела Бање и Гостиљског врела за десетогодишње периоде осматрања. Укључивањем више независних величина, коефицијенти корелације безначајно расту, те је препорука да се максимално 3 независне променљиве укључе у симулациони модел. ...Вељко Мариновић, Весна Ристић Вакањац, Саша Милановић, Љиљана Васић, Бранислав Петровић, Душан Поломчић, Радисав Голубовић. "Примена ауторегресионих модела за потребе краткорочних прогноза истицања карстних врела" in 50. симпозијум о операционим истраживањима - SYM-OP-IS 2023, Тара, 18–21. септембар 2023., Београд : Медија центар „Одбрана” (2023)
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Simulation of Hydrogeological Environmental Discharge in Case of Interruption Constant Observations
Marina Čokorilo Ilić, Dragoljub Bajić, Miroslav Popović. "Simulation of Hydrogeological Environmental Discharge in Case of Interruption Constant Observations" in International Scientific Conference - Sinteza 2024, Belgrade, 16. maj 2024, Singidunum University (2024). https://doi.org/10.15308/Sinteza-2024-288-294
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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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Definition of groundwater genesis and circulation conditions of the complex hydrogeological karst system Mlava–Belosavac–Belosavac-2 (eastern Serbia)
Ljiljana Vasić, Saša Milanović, Zoran Stevanović, Laszlo Palcsu. "Definition of groundwater genesis and circulation conditions of the complex hydrogeological karst system Mlava–Belosavac–Belosavac-2 (eastern Serbia)" in Carbonates and Evaporites, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s13146-020-00550-3
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Simulacija isticanja odabranih karstnih vrela pirotske kotline
Saša Milanović, Branislav Petrović, Vesna Ristić Vakanjac, Ljiljana Vasić, Veljko Marinović, Petar Vojnović (2022)Analiza recesije, autokorelaciona i kroskorelaciona analiza vremenskih serija padavina i isticanja podzemnih voda karstnih vrela Krupac i Gradište (Stara planina, JI Srbija) izvršena je radi formiranja stohastičkog autoregresivno-krosregresivnog modela (ARCR) i kratkoročne prognoze dnevnih vrednosti izdašnosti. Usled postojanja heterogenosti i anizotropnosti karstne izdani veoma je komplikovano i zahtevno odrediti prostornu distribuciju podzemnih voda u okviru karstnog hidrogeološkog sistema, te je primenljivost determinističkih modela minimizirana. Stoga je upotreba stohastičkog modela u ovom slučaju svrsishodnija. Autokorelogram izdašnosti vrela Krupac pokazao je ...Saša Milanović, Branislav Petrović, Vesna Ristić Vakanjac, Ljiljana Vasić, Veljko Marinović, Petar Vojnović. "Simulacija isticanja odabranih karstnih vrela pirotske kotline" in Vodoprivreda, Српско друштво за одводњавање и наводњавање, Београд, Академија инжењерских наука Србије (2022)
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Режим изворских вода из кристаластих стена у планинским подручјима на примеру Топлог Дола на Власини (Југоисточна Србија)
Сунчица Гардијан, Владимир Живановић, Сава Магазиновић, Ђорђе Мандић, Саша Стојадиновић. "Режим изворских вода из кристаластих стена у планинским подручјима на примеру Топлог Дола на Власини (Југоисточна Србија)" in Zbornik radova XVI srpskog Simpozijum o hidrogeologiji sa međunarodnim učešćem, Univerzitet u Beograd, Rudarsko-geološki fakultet (2022)
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Convective heat transfer in centrifugal pumps lifted wells: the case of South-Eastern Europe waxy wells
Electric submersible pumps (ESP) are applied in wells where additional energy is needed to ensure discharge of the fluid to the surface through the tubing. At the discharge side of the pump the fluid has bigger velocity, thus the pump induces a forced convection between the fluid and the tubing inner surface. Understanding of convective heat transfer in wellbores and analyses of influential parameters provides a possibility to optimise value of convective heat transfer coefficient in order to avoid ...Bojan Martinovic, Marija Živković, Branko Grubač. "Convective heat transfer in centrifugal pumps lifted wells: the case of South-Eastern Europe waxy wells" in International Journal of Oil, Gas and Coal Technology, Inderscience Publishers (2021). https://doi.org/10.1504/IJOGCT.2021.10043281
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Definition of Circulation Conditions and Groundwater Genesis of the Complex Krupaja Hydrogeological Karst System (Eastern Serbia)
Management, Monitoring, Policy and Law,Renewable Energy, Sustainability and the Environment, Geography, Planning and Development, Building and Construction... at minimum and maximum; right—schematic hydroge- ological profile of the Krupaja Spring. 1—min. discharge 0.16 m?/s; 2—max. discharge > 30 m3/s; 3—schematic cross-section of Krupaja Spring, discharge zone; 4—cross section of the explored karst channels of the Krupaja Springj. As previously mentioned ...
... through large and well-developed karst channels. This model of karst channels, its spatial position and dependence in relation to recharge and discharge, indicates a very complex and well-developed karst system. For the purposes of forming the model, as shown in the following text, a large number ...
... purposes of defining the circulation conditions within the karst aquifer that drains via Krupaja Spring, parts of the model from the recharge to the discharge zone were used (Figure 4D) [19]. I, illl 3D Model of karst channels distribution in Krupaja spring area 3D model of karst conduits watershead ...Ljiljana Vasić, Saša Milanović, Tina Dašić. "Definition of Circulation Conditions and Groundwater Genesis of the Complex Krupaja Hydrogeological Karst System (Eastern Serbia)" in Sustainability, MDPI AG (2023). https://doi.org/10.3390/su151411146
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Evaluation of the effects of wastewater heat pump integration into district heating systems by simulation
Dejan Ivezić, Marija Živković, Dimitrije Manić, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović (2023)The integration of wastewater heat pumps (using purified water) in district heating systems is analyzed in this paper. The simulation procedure is proposed to analyze the impacts of stochasticity of purified water temperature and flow to heat pump integration and operation. The analysis includes calculation of the daily and seasonal coefficient of performance, as well as fossil fuel savings and CO2 emission reduction due to wastewater heat pump use. The proposed procedure is implemented for the case study in ...Dejan Ivezić, Marija Živković, Dimitrije Manić, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović. "Evaluation of the effects of wastewater heat pump integration into district heating systems by simulation" in Thermal Science, National Library of Serbia (2023). https://doi.org/10.2298/TSCI220813168I
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Linearization of Input Signal as a Necessary Tool in Stochastic Modeling of Karst Groundwater
Veljko Marinović (2021)Modelling of karst hydrogeological systems is a very complicated task, bearing in mind that for a deterministic model one should know the internal physical processes of precipitation transformation into discharge, while for a stochastic model nonlinear dynamic systems such as karst should be simulated by linear regression equations. Stochastic models need linearization of input time series due to often large residual in the recession period. This occur because the model is not able to absorb single rain episodes, which ...Veljko Marinović. "Linearization of Input Signal as a Necessary Tool in Stochastic Modeling of Karst Groundwater" in Karst: From Top to Bottom, Belgrade, 6.6.2021., Belgrade : Centre for Karst Hydrogeology (2021)
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An example of karst catchment delineation for prioritizing the protection of an intact natural area
Vesna Ristić Vakanjac, Zoran Stevanović, Aleksandra Maran Stevanović, Boris Vakanjac, Marina Čokorilo Ilić (2015)Проучавано је карстни извор Перућац као главни дрен подручја планине Таре у западној Србији у циљу процене његовог режима отицања, резерви воде и дефинисања његове сливне површине. Извор се налази у североисточној, унутрашњој зони класичног динарског крша, коју карактерише доминантно проширење висококарстификованих тријаских кречњака, слабо развијена хидрографска мрежа са много понора и густе шуме. Тара је један од пет националних паркова у Србији. Циљ рада је био да се идентификује заштитна зона високог приоритета у оквиру очуваног природног подручја ...Vesna Ristić Vakanjac, Zoran Stevanović, Aleksandra Maran Stevanović, Boris Vakanjac, Marina Čokorilo Ilić. "An example of karst catchment delineation for prioritizing the protection of an intact natural area" in Environmental Earth Science (2015). https://doi.org/10.1007/s12665-015-4390-y
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Hydrochemical changes and groundwater grouping data by multivariate statistical methods within one karst system: recharge–discharge zone (Eastern Serbia case study)
Ljiljana Vasić, Dragana Živojinović, Vladana Rajaković-Ognjanović. "Hydrochemical changes and groundwater grouping data by multivariate statistical methods within one karst system: recharge–discharge zone (Eastern Serbia case study)" in Carbonates and Evaporites, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s13146-019-00548-6
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Determining the Groundwater Balance and Radius of Influence Using Hydrodynamic Modeling: the Case Study of the Groundwater Source “Šumice” (Kikinda, Serbia)
A groundwater flow model was developed to simulate groundwater extraction from the public water supply source of the City of Kikinda. The hydrodynamic model includes the municipal groundwater source of Kikinda (Šumice and the Jezero Well), but also an extended area where there are groundwater sources that provide water supply to three factories: (MSK, TM and LŽT - Kikinda). Hydrodynamic modeling, based on the numerical method of finite differences will show the groundwater balance of the sources in the ...... recorded operating hours and discharge rates. The well screens were Journal of Sustainable Development of Energy, Water and Environment Systems Year 2015 Volume 3, Issue 3, pp 217-229 224 specified using as-built dimensions and positions. The discharge rates of the production wells ...
... infiltration of precipitation and surface water, since there is a good hydraulic contact between the aquifer and the river. The aquifer is drained naturally, at times of low river stages when groundwater flow is directed towards rivers, and artificially - through drilled and dug wells. The confined ...
... tool for delineating groundwater protection zones [14]. Particle tracking simulations can be used to determine travel times from recharge to discharge areas along identified flowpaths [15]. Using a standard numerical flow and transport code and a technique based on adjoint theory, and combining ...Dušan Polomčić, Dragoljub Bajić, Jelena Zarić. "Determining the Groundwater Balance and Radius of Influence Using Hydrodynamic Modeling: the Case Study of the Groundwater Source “Šumice” (Kikinda, Serbia)" in Journal of Sustainable Development of Energy, Water and Environment Systems (2015). https://doi.org/10.13044/j.sdewes.2015.03.0017
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An oilfield in Libya: A new model to enhance waste water disposal
Dušan Danilović, Vesna Karović Maričić, Nori Elhaddad, Branko Leković. "An oilfield in Libya: A new model to enhance waste water disposal" in Energy & Environment (2016)
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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 ...... the pump system'"s discharge phase, during which the pressure inside the cylinder remains constant and is equal to the sum of the discharge pressure and the pressure needed to move the fluid through the traveling valve and the interior of the plunger. During the discharge cycle, the plunger moves ...
... the reservoir is called the suction pressure, while the pressure at which the fluid exits the pump is referred to as the discharge pressure. The difference between the discharge pressure and the suction pressure is known as the pumping pressure, which represents the increase in the fluid's potential ...
... pump is achieved through the movement of the piston in the stationary cylinder. Design solutions for the suction and discharge valves—larger suction valve and smaller discharge valve—as well as higher volumetric efficiency in cases where pumping is performed when the dynamic pressure is lower than ...Ana Ponoćko. Design of a sucker rod pumping system, 2024
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A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)
... boundary conditions of the hydrogeologic system included effective infiltration and boundary conditions: river, general head boundary, drainage, specified discharge - drainage wells, specified discharge - “no flow” cells, and flow barrier. Among the so-called initial conditions, which characterize the ...
... and their geometry. The focus is on aquifers and their spatial relationships. Groundwater levels, directions of groundwater flow, and recharge and discharge zones of the hydrogeologic system can also be depicted. Such a hydrogeologic model constitutes the groundwork for the next step - conversion ...
... them. Polomčić et al. (2016) presented a quantitative 2013 groundwater balance of Tamnava - West Field, and also determined aquifer recharge and discharge in the form of model inflow and outflow. Given that there is a groundwater control system in place, the rate of groundwater extraction is greater ...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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CC-PESTO: a novel GIS-based method for assessing the vulnerability of karst groundwater resources to the effects of climate change
The new GIS-based CC-PESTO method is shown to successfully assess and map the vulnerability/resilience of karst aquifers to effects of climate change. Karst aquifers were chosen due to their importance at the global level and widespread utilisation in potable water supply and irrigation, but also because of their hydrogeological complexity. The method was developed to assess the intrinsic vulnerability of aquifers, without considering the direct impact of variable climate factors, but considering the adaptive capacity of aquifers in response ...Zoran Stevanović, Veljko Marinović, Jelena Krstajić. "CC-PESTO: a novel GIS-based method for assessing the vulnerability of karst groundwater resources to the effects of climate change" in Hydrogeology Journal, Springer Science and Business Media LLC (2020). https://doi.org/10.1007/s10040-020-02251-6
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Vulnerability methods in hard rock formation as a basis for groundwater risk assessment – from resource to source
Groundwater in a hard rock formation is most endangered at places where a potential source can discharge contaminants that can reach the saturated zone of an aquifer. In these circumstances, an essential tool for groundwater protection is the contamination risk map. This map is based on the integration of two maps: a hazards map, i.e., map of potential sources of contamination and a vulnerability map. The selection of a proper vulnerability method is an important task since the resulting ...karta rizika od kontaminacije, ranjivosti podzemnih voda, DRASTIC, EPIK, PI, COP, Nacionalni park TaraVladimir Živanović, Igor Jemcov, Veselin Dragišić. "Vulnerability methods in hard rock formation as a basis for groundwater risk assessment – from resource to source" in Geologia Croatica, Croatian Geological Survey (2022). https://doi.org/10.4154/gc.2022.23
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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