Претрага
95 items
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Funkcionisanje i uticaj epikarsta na režim, bilans i kvalitet podzemnih voda istočnog dela karstnog sistema Suve planine
Branislav Z. Petrović (2020)Epikarst je deo karstne izdani koji se nalazi u okviru nadizdanske zone i predstavlja kompleksnu tačku dodira i mešanja nekonsolidovanog materijala sa površine terena, ostataka karbonatnih stena izmenjenih korozivnim delovanjem vode, živog sveta i njihovih ostataka, koja je delimično zasićena podzemnom vodom. Kompletan sud o stepenu razvoja i prisustva epikarsta na nekom krečnjačkom terenu moguće je doneti uz multidisciplinarna i obavezna detaljna hidrogeološka istraživanja. Poligon za sprovedena istraživanja je bio karstni masiv Suve planine, koja u geološkom i geografskom smislu ...epikarst, karstni sistem, podzemne vode, procesi samoprečišćavanja, hidrohemijski i mikrobiološki procesi u podzemnoj vodiBranislav Z. Petrović. Funkcionisanje i uticaj epikarsta na režim, bilans i kvalitet podzemnih voda istočnog dela karstnog sistema Suve planine, Beograd : [B. Petrović], 2020
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GNSS Time Series as a Tool for Seismic Activity Analysis Related to Infrastructure Utilities
Sanja Tucikešić, Ankica Milinković, Branko Božić, Ivana Vasiljević, Mladen Slijepčević . "GNSS Time Series as a Tool for Seismic Activity Analysis Related to Infrastructure Utilities" in Contributions to International Conferences on Engineering Surveying. Springer Proceedings in Earth and Environmental Sciences, Dubrovnik, Croatia, October 22-23, 2020, Springer, Cham (2021). https://doi.org/10.1007/978-3-030-51953-7_21
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Insights into dike nucleation and eruption dynamics from high-resolution seismic imaging of magmatic system at the East Pacific Rise
Milena Marjanović, Suzanne M. Carbotte, Alexandre Stopin, Satish C. Singh, René-Édouard Plessix, Miloš Marjanović, Mladen R. Nedimović, Juan Pablo Canales, Hélène D. Carton, John C. Mutter, Javier Escartín (2023)Milena Marjanović, Suzanne M. Carbotte, Alexandre Stopin, Satish C. Singh, René-Édouard Plessix, Miloš Marjanović, Mladen R. Nedimović, Juan Pablo Canales, Hélène D. Carton, John C. Mutter, Javier Escartín. "Insights into dike nucleation and eruption dynamics from high-resolution seismic imaging of magmatic system at the East Pacific Rise" in Science Advances, American Association for the Advancement of Science (AAAS) (2023). https://doi.org/10.1126/sciadv.adi2698
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Trans-Lithospheric Diapirism as a Possible Mechanism for Ophiolite Emplacement?
Nikola Stanković, Taras Gerya, Vladica Cvetković, Vesna Cvetkov. "Trans-Lithospheric Diapirism as a Possible Mechanism for Ophiolite Emplacement?" in EGU General Assembly 2024, Vienna, 14-19 April 2024, Göttingen : Copernicus GmbH (2024). https://doi.org/10.5194/egusphere-egu24-568
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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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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 ...... Angle (degrees) Plunger Veloctty Plot Maximum Upstroke Polished Rod Velocity (m/s) : ,638 Maximum Downstroke Polished Rod Velocity (m/s) : 651 Maximum Upstroke Plunger Velocity (m/s) : ,662 Maximum Downstroke Plunger Velocity (m/s) : 652 Pl un ge r Ve lo ci ty (m /s ) e 0 O 2 3 4 % 6G ...
... 20 30 20 %0 MO XO Poniton (cm) (Crank Angle (degrees) e [j L Lj [j s s a LJ s š 6.1. Figure Well XX-1 in RodStar 40 VELOCITY PLOTS PR Velociy vs Postton PR Velocity vs Crank Angle- PR Ve lo ci ty (m /s ) e PR Ve lo ci ty (m /s ) e 0 MK 2 % “ M O NM M % 0 '#4”Rn 8 3 ć&s20 ...
... expressed by the following equation: nsid = — 3.4 23 FOIRO Rp = CeP3Vsiž — Rp- inlet pressure, or the pressure below the pump (bar) — V5l - velocity of liquid flow through the annular space of the anchor reduced to the full cross-section of the annular space of the anchor without gas (m/s) ...Ana Ponoćko. Design of a sucker rod pumping system, 2024
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The Flow Conditions in the Epikarst Zone of a Karst Aquifer. Case Study: Suva planina Mt., East Serbia
Branislav Petrović (2023)The epikarst as a part of the karst aquifer represents a complex point of contact and mixing of unconsolidated material from the terrain surface, carbonate rocks altered by “corrosive” water, flora and fauna (and remains of), which is partially saturated with groundwater. Significant amounts of (plant accessible) water, and other solutes and particles, can be stored in this zone for extended periods of time. Thus, attenuation or biochemical processes could start in this layer and change quality of infiltrated ...Branislav Petrović. "The Flow Conditions in the Epikarst Zone of a Karst Aquifer. Case Study: Suva planina Mt., East Serbia" in International Scientific Conference "Man and Karst 2022", CIRS - Centro Ibleo di Ricerche Speleo-Idrogeologiche (2023)
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The Flow Conditions in the Epikarst Zone of a Karst Aquifer. Case Study: Suva planina Mt., East Serbia
Branislav Petrović (2022)The epikarst as a part of the karst aquifer represents a complex point of contact and mixing of unconsolidated material from the terrain surface, carbonate rocks altered by “corrosive” water, flora and fauna (and remains of), which is partially saturated with groundwater. Recharge of karst aquifers, usually, occurs via the unsaturated zone which uppermost part could be epikarst zone. Significant amounts of (plant accessible) water, and other solutes and particles, can be stored in this zone for extended periods ...Branislav Petrović. "The Flow Conditions in the Epikarst Zone of a Karst Aquifer. Case Study: Suva planina Mt., East Serbia" in International Scientific Conference - Man and Karst 2022, Custonaci, Italy, 12-16.09.2022, Gruppo Grotte Ragusa - C.I.R.S. (2022)
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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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The influence of Al<sup>3+</sup>ion on porcine pepsin activity<i>in vitro</i>
The in vitro effect of Al3þ ions in the concentration range 1.7·1026M–8.7·1023M on pepsin activity at pH 2, via kinetic parameters and its electrophoretic mobility was evaluated. Kinetic study demonstrated the existence of an activation effect of Al3þ at pH 2 on pepsin molecule. Kinetic analysis with respect to concentrations of haemoglobin showed that Al3þ ions increase the maximal velocity (Vmax) and kcat values rather than apparent affinity for substrate (KS) implying the non-competitive nature of activation which indicated ...... inset. A double reciprocal plot of the velocity s. substrate concentrations at increasing concentrations of Al ions resulted in a family of linear plots intersecting at 1/[Hb] axis (Figure 2). The Lineweaver-Burk plots show that increase of reaction velocity in the presence of ALP?* ions is p ...
... effect of A at pH 2 on pepsin molecule. Kinetic analysis with respect to concentrations of haemoglobin showed that A~ ions increase the maximal velocity (Vmax) and k.a. values rather than apparent affinity for substrate (Ks) implying the non-competitive nature of activation which indicated that aluminium ...
... Estimation of hinetic barameters Kinetic analysis was carried out according to a slightly modified method of Anson [26], by following the initial velocity of the enzymatic reaction in the absence and presence of AU?(1.7-·10 "-8.7·:10 *~M) and increasing concentrations of haemoglobin (0.025— 4·:10 ...Vesna M. Pavelkić, Kristina R. Gopcević, Danijela Z. Krstić, Marija A. Ilić. "The influence of Al3+ion on porcine pepsin activityin vitro" in Journal of Enzyme Inhibition and Medicinal Chemistry, Informa UK Limited (2008). https://doi.org/10.1080/14756360701841095
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Regional rockfall exposure assessment, experience from Serbia
Rockfalls are common in hilly and mountainous areas, especially along roads with engineered slopes and cuts. Such is the case for most of the state and local road routes in Central, Serbia, which was the subject in this case study. A road network of 276 km covering roughly 1700 km2 between the cities of Kraljevo, Čačak and Ivanjica is presented. Assessing of such wide areas needs to be conducted from large to site-specific scale, i.e., using GIS spatial tools ...Miloš Marjanović, Biljana Abolmasov, Uroš Đurić, Jelka Krušić, Snežana Bogdanović. "Regional rockfall exposure assessment, experience from Serbia" in 5th Regional symposium on landslides in Adriatic–Balkan Region, 23-26 March 2022, Faculty of Civil Engineering, University of Rijeka and Faculty of Mining, Geology and Petroleum Engineering, University of Zagreb (2022)
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Complex geophysical survey on solving the problem of water loss in the karst terrain reservoir
Branislav Sretković, Dejan Vučković (2023)Geophysical surveys in karst terrain are always a specific challenge. Each of them requires a careful consideration of the problem, specific conditions on the ground, the selection of adequate methods applicable in that specific and unique karst area. But they should have one thing in common: a complex approach and looking at the problem from wider to narrower, with a gradual narrowing of the investigation area, increasing the spatial precision and resolution of the obtained data. On the example of ...Branislav Sretković, Dejan Vučković. "Complex geophysical survey on solving the problem of water loss in the karst terrain reservoir" in 8th Symposium Geoscience 2023, Bucharest, 9-11. November 2023, Bucharest : Editura Cetatea de Scaun (2023)
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Анализа одрона у стенским косинама: савремени приступи
Милош Марјановић (2023)У Србији и региону познате су бројне појаве одрона које су изазвале велике застоје саобраћаја, материјалне штете или чак имале фаталне исходе, па их је потребно непрестано пратити и изучавати. Mодeловањe одрона скопчано је са ниским нивоом поузданости, али савремене технологије омогућавају да сe такви изгледи донекле побољшају. Једна од технологија која чини искорак утом правцу јe LiDAR-ско скенирање, које обезбеђује детаљне топографске подлоге у виду облака тачака високе резолуције и тачности. Поступак анализе одрона може се свести на: ...Милош Марјановић. "Анализа одрона у стенским косинама: савремени приступи" in Записници Српског геолошког друштва, Београд : Српско геолошко друштво (2023)
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Linear-motor plunger pump increases lifting efficiency
Bojan Martinović, Dušan Đekić, Dušan Danilović, Pavel Isaev. "Linear-motor plunger pump increases lifting efficiency" in Oil & Gas Journal (2022)
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Analysis of the Influence of Burden Deviation from the Designed One on the Intensity of the Blast Vibration
Stefan Milanović, Lazar Kričak, Milanka Negovanović, Nikola Simić, Jovan Marković, Nikola Đokić (2023)This paper presents an analysis of the influence of burden deviation from the designed one on the intensity of blasting vibrations through the use of laboratory and field examinations. By definition, the burden represents the shortest distance from the axis of an explosive column charge to the free surface. It should be measured along the entire hole length, although, in practice, it is often measured only on the bench surface as the shortest distance from the axis of the ...Stefan Milanović, Lazar Kričak, Milanka Negovanović, Nikola Simić, Jovan Marković, Nikola Đokić. "Analysis of the Influence of Burden Deviation from the Designed One on the Intensity of the Blast Vibration" in Applied Sciences, MDPI AG (2023). https://doi.org/10.3390/app132312837
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Primena programa UVSZ pri zaštiti od miniranja
Primena energije eksploziva tj. miniranje, predstavlja osnovni način eksploatacije čvrstih mineralnih sirovina u rudarstvu. Miniranjem se postižu vrlo povoljni tehnoekonomski pokazatelji, koje nažalost prate i negativni efekti miniranja. U cilju zaštite životne sredine potrebno je za svaku radnu sredinu odrediti jednačinu oscilovanja stenske mase pri miniranju. Ova jednačina definiše promenu brzine oscilovanja stenske mase u zavisnosti od rastojanja, količine eksploziva, uslova izvođenja miniranja i geoloških karakteristika stenske... In order to protect the environment, it is necessary to determine the rock mass oscillation equation for each working environment during blasting. This equation defines the change of rock mass oscillation velocity depending on distance, explosive amount, conditions of blasting and geological c ...
... y. In order to protect the environment, it is necessary to determine the rock mass oscillation equation for each working environment during blasting. This equation defines the change of rock mass oscillation velocity depending on distance, explosive amount, conditions of blasting and geological char ...
... Oscillations of the particles of rock mass at terrain are felt as shock. Based on application of this equation, we are able to predict the oscillation velocity for each subsequent blasting in a given working environment. On that way, shocks from blasting, in a seismic sense, are brought under control ...Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac, Rade Tokalić. "Primena programa UVSZ pri zaštiti od miniranja" in XIII skup privrednika i naučnika SPIN’21, Industrija 4.0 – mogu nosti, izazovi i rešenja za digitalnu transformaciju privrede, Univerzitet u Beogradu, Fakultet organizacionih nauka (2021)
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Fragmentation Size Prediction of Blasted Material Using a Specialized Software for Drilling and Blasting
Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić, Miljan Gomilanović (2024)Design and optimizing the drilling and blasting parameters, should fill the requirements for the capacity, fragmentation size, and technical characteristics of loading and transport equipment, and enable a safe work at the open pit. Besides mentioned, it also achieves the minimal impact on the environment of the open pit and decreases the negative effects on the environment, especially in the blast vibration and flyrock. To obtain the best possible blasting effects and consider all the factors, a specialized software is ...Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić, Miljan Gomilanović. "Fragmentation Size Prediction of Blasted Material Using a Specialized Software for Drilling and Blasting" in The 55th International October Conference on Mining and Metallurgy, Mining and Metallurgy Institute Bor (2024). https://doi.org/10.5937/IOC24077M
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Моделирање утицаја одступања линије најмањех отпора од пројектоване на интензитет потреса од минирања
Стефан Милановић (2024)Према дефиницији линија најмањег отпора представља најкраће растојање од центра минског пуњења до слободне површине. Oвим истраживањем представљен је утицај линије најмањег отпора, као и њеног одступања од пројектоване на интезитет потреса услед минирања. Проблем линије најмањег отпора је веома заступљен у пракси, где се занемарује изглед слободне површине, који може бити врло неправилан. Линију најмањег отпора је потребно мерити целом дужином минске бушотине према слободној површини, иако је у пракси случај да се мери најчешће као растојање од ...линија најмањег отпора, 3D модел, потреси услед минирања, минирање, слободна површина, метода раздвојених елеменатаСтефан Милановић. Моделирање утицаја одступања линије најмањех отпора од пројектоване на интензитет потреса од минирања, Београд : [С. Милановић], 2024
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Debris-flow Susceptibility Assessment in Flow-R: Ribnica River Case Study
Debris flows are among the most dangerous erosional geohazards due to the fast rate of movement and long runout zones. Even though the initiation can be triggered in mountainous areas, inhabited and with steep slopes, their propagation and deposition can endanger not only buildings and infrastructure in the urbanized areas, but also threaten human lives. As these initiation areas usually represent unattainable terrains with rapid vegetation cover development, field observations and aerial photo analysis become high-demanding tasks. Consequently, medium-to-regional ...Ksenija Micić, Miloš Marjanović, Biljana Abolmasov . "Debris-flow Susceptibility Assessment in Flow-R: Ribnica River Case Study" in Proceeding of the 6th Regional Symposium on Landslides in the Adriatic-Balkan Region, ReSyLAB 2024, University of Belgrade, Faculty of Mining and Geology (2024). https://doi.org/https://doi.org/10.18485/resylab.2024.6
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Influence of DEM resolution on numerical modelling of debris flows in RAMMS - Selanac case study
Debris flows induced by intensive rainfall represent very hazardous phenomena in many parts of the World. Methods for prediction of runout distance of flow like mass movements are different and depending on the input data, rheology, and available or appropriate numerical solution. However, sometimes it is not easy to obtain pre event and post event high-resolution data in the rural or mountainous area. Thus, the topology of terrain is the most important input parameter for the every real case ...... Institute for Snow and Avalanche Research (SLF, Davos). The mass balance equation incorporates the field variables flow height H (x, y,t) and flow velocity U (x, y,t) and is given by: 𝑄(𝑥, 𝑦, 𝑡) ˙ = 𝜕𝑡𝐻 + 𝜕𝑥 (𝐻 𝑈𝑥 ) + 𝜕𝑦 (𝐻 𝑈𝑦 ) (1) where Q(x, y,t) ˙ describes the mass ...
... dry-Coulomb term (friction coefficient / scaling with the normal stress and the viscous or turbulent friction (coefficient/ depending on the flow velocity U (Christen et al.,2010a, 2012; Bartelt et al., 2013): 𝑆𝑓 = μ𝜌𝑔𝐻 cos 𝜑 + 𝜌𝑔𝑢2𝜉 (4) where ρ is the mass density, g is the gravitational ...Jelka Krušić, Biljana Abolmasov, Mileva Samardžić Petrović. "Influence of DEM resolution on numerical modelling of debris flows in RAMMS - Selanac case study" in 4th Regional Symposium on Landslides in the Adriatic Balkan Region, 23-25 October 2019, Sarajevo, Bosnia and Herzegovina, Geotechnical Society of Bosnia and Herzegovina (2019). https://doi.org/ 10.35123/ReSyLAB_2019