Претрага
315 items
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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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Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention
Gas wells, particularly those situated onshore, play a vital role in the global energy sector by supplying a significant portion of natural gas. However, operational challenges, notably gas hydrate formation, pose substantial issues, leading to complications such as flowline blockages and unexpected well shutdowns. Gas hydrates, crystalline structures resembling ice, ...Gas Well, Gas Hydrate Formation, Well Modeling, Well Performance Optimization, Choke Position Adjustments, Methanol InjectionMilica Ješić, Bojan Martinović, Stefan Stančić, Miroslav Crnogorac, Dušan Danilović. "Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention" in Underground Mining Engineering, Beograd : Rudarsko-geološki fakultet (2023)
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Gate Road Support Deformation Forecasting Based on Multivariate Singular Spectrum Analysis and Fuzzy Time Series
Luka Crnogorac, Rade Tokalić, Zoran Gligorić, Aleksandar Milutinović, Suzana Lutovac, Aleksandar Ganić (2021)Underground mining engineers and planners in our country are faced with extremely difficult working conditions and a continuous shortage of money. Production disruptions are frequent and can sometimes last more than a week. During this time, gate road support is additionally exposed to rock stress and the result is its progressive deformation and the loss of functionality of gate roads. In such an environment, it is necessary to develop a low-cost methodology to maintain a gate road support system. ...deformacije podgrade, lasersko skeniranje, višekanalna singularna spektralna analiza, prognoza, klasterisanje fuzzy vremenskih serija... n of real two-dimensional support to an artificial one-dimensional support. The position of the marker m ( → v , t ) , induced by rock stress, changes according to the following vector equation (Figure 2): → v (t) = → v (t− 1) + → u (t), t = 1, 2, . . . , N , (1) where → v (t)—the position vector ...
... or column data of the matrix ∆V. We focus on each column data in order to see how displacement intensity of configuration of the gate road support changes over time. For that purpose, we apply the concept of fuzzy time series with multiple observations [20–22]. A fuzzy set A of ∆VM×N is defined as follows: ...
... or column data of the matrix AV. We focus on each column data in order to see how displacement intensity of configuration of the gate road support changes over time. For that purpose, we apply the concept of fuzzy time series with multiple observations [20-22]. A fuzzy set A of AViyx.n is defined as ...Luka Crnogorac, Rade Tokalić, Zoran Gligorić, Aleksandar Milutinović, Suzana Lutovac, Aleksandar Ganić. "Gate Road Support Deformation Forecasting Based on Multivariate Singular Spectrum Analysis and Fuzzy Time Series" in Energies, MDPI (2021). https://doi.org/https://doi.org/10.3390/en14123710
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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... (reflected on various design aspects); • adaptive capacities—aimed at enabling year-round functioning bearing in mind sea- sonal changes as well as prospective changes (anticipated and unexpected) throughout the facility’s lifespan; • infrastructure independence—aimed at off-grid functionality, especially ...
... reaching a given site’s full capacity. Simple layout and structure of individual modules makes them very flexible, allowing for partial adaptations, changes in use, or even regaining functionality after an extreme catastrophic event and severe material damage. 3.2.2. Sizing and Positioning of Open-Air ...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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Low-temperature phase transition and magnetic properties of K3YbSi2O7
Predrag Dabić, Volker Kahlenberg, Biljana Krüger, Marko Rodić, Sabina Kovač, Jovan Blanuša, Zvonko Jagličić, Ljiljana Karanović, Václav Petříček, Aleksandar Kremenović (2021)alkalni silikati elemenata retkih zemalja, fazni prelazi, magnetne karakteristike, razdvajanje kristalnog polja, silikati lantanica... one silicon and three unique oxygen sites. The structural phase transition is characterized by small shifts of the atomic posi- tions and minor changes in the coordination environments of the potassium ions. The Yb3+ cations are octahedrally coordinated with four oxygen atoms at Yb–O1 distances ...
... ytterbium, one silicon and three unique oxygen sites. The structural phase transition is characterized by small shifts of the atomic posi- tions and minor changes in the coordination environments of the potassium ions. The Yb** cations are octahedrally coordinated with four oxygen atoms at Yb-Ol distances of ...
... therefore, to assume that a slight level reposi- tioning (if any) due to the modest variation of the Yb—O distances, will not introduce notable changes in the magnetic behaviour above 100 K. However, it is also reasonable to assume that, to some (unknown) extent, the parameter values listed in Table ...Predrag Dabić, Volker Kahlenberg, Biljana Krüger, Marko Rodić, Sabina Kovač, Jovan Blanuša, Zvonko Jagličić, Ljiljana Karanović, Václav Petříček, Aleksandar Kremenović. "Low-temperature phase transition and magnetic properties of K3YbSi2O7" in Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials, International Union of Crystallography (IUCr) (2021). https://doi.org/10.1107/S2052520621006077
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Serbian Society of Geomorphologists
Dragana Đurić, Jelena Ćalić (2019)Dragana Đurić, Jelena Ćalić. "Serbian Society of Geomorphologists" in GeomorForum 2019: Landforms related to plains of Serbia and its neighboring area, Conference Programme and Abstracts, Beograd, 10-12. maj 2019, Serbian Society of Geomorphologists (2019)
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Effects of Energy Production and Consumption on Air Pollution in Serbia
Marija Živković (2019)Energy production and combustion, mostly from unregulated or inefficient fuel combustion, are the single most important anthropogenic sources of air pollutant emissions. Energy sector in Serbia is highly fossil fuel intensive: 87.88% of energy consumed in Serbia is related to fossil fuels, while almost 95% of energy sources are combusted. In 2017. energy related carbon dioxide emission in Serbia is was 47.95 million tones. The main source of carbon dioxide emission was coal, responsible for almost 70% of energy ...... level of the country, region etc 4. Nowadays the most of attention of is dedicated to reduction of carbon dioxide emission and mitigation of climate changes 5, while other pollutants receive less attention. Energy production and combustion, mostly from unregulated or inefficient fuel combustion, are the ...Marija Živković. "Effects of Energy Production and Consumption on Air Pollution in Serbia" in Mining and Environmental Protection-MEP 2019, University of Belgrade, Faculty of Mining and Geology (2019)
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Elektromagnetska sprega sistema litosfera-atmosfera-jonosfera
Aleksandra B. Kolarski (2016-08-25)Radio talasi vrlo niskih frekvencija VLF (eng. Very Low Frequency) frekventnog opsega od 3 do 30 kHz, koji se prostiru talasovodom Zemlja-jonosfera (50 -90 km) su, kao što je poznato, efikasni i nezamenljivi u osmatranju pojava u niskoj jonosferi, sa tla...prostiranje talasa vrlo niskih frekvencija, talasovod Zemlja-jonosfera, globalno električno kolo, atmosfersko električno pražnjenje, kratkotrajne svetlosne pojave... . Ionization changes driven by different phenomena resulting from the Sun-Earth interaction can be successfully VLF detected by analyzing the amplitude and phase delay of the propagating signal at different appropriate time scales. In this study we focus on ionization changes that most dominantly ...
... Cummer, S. A., Lyons, W. A. (2004). Lightning charge moment changes in U.S. high plains thunderstorms. Geophys. Res. Lett., 31, doi:10.1029/-2003GL019043. Cummer, S. A., Lyons, W. A. (2005). Implications of impulse charge moment changes in sprite-producing and non-sprite-producing lightning. J ...
... Amplitude Logger) receiving system, located at the Institute of Physics, Belgrade (44.85 N; 20.38 E). The effects of induced ionization changes have been observed along different propagation paths, between a selected transmitter and the Belgrade receiver. VLF data from transmitters NAA/24 ...Aleksandra B. Kolarski. "Elektromagnetska sprega sistema litosfera-atmosfera-jonosfera" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2016-08-25)
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Valorization of non-balanced coal reserves in Serbia for underground coal gasification
David Petrović, Lazar Kričak, Milanka Negovanović, Stefan Milanović, Jovan Marković, Nikola Simić, Ljubisav Stamenić (2019)In the name of a better and safer energy future, it is our responsibility to focus our knowledge and activities to save on imported liquid and gas fossil fuels, as well as coal on which energy security of Serbia is based. The rationalization in the use of available energy resources certainly positively affects economy and the environment of a country. This paper indicates motivations for the application of the underground coal gasification process, as well as surface gasification for ...... different physical-chemical conditions and interdependencies, where the concentration of dissolved substances in them is much more diverse and changes according to the specific rules all the time. This is especially the case with the flow of aquifer waters, where the pollution process itself, ...
... concentration of pollutants to the allowed values according to the adopted norms, which are of interest from the perspective of the forecast of changes in the water quality of the aquifer. Measures of preventive character are those that can prevent the possibility of con- tamination of groundwater ...David Petrović, Lazar Kričak, Milanka Negovanović, Stefan Milanović, Jovan Marković, Nikola Simić, Ljubisav Stamenić. "Valorization of non-balanced coal reserves in Serbia for underground coal gasification" in Thermal Science (2019). https://doi.org/10.2298/TSCI190725390P
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Influence of paleoenvironmental conditions on distribution and relative abundance of saturated and aromatic hydrocarbons in sediments from the NW part of the Toplica basin, Serbia
Nikola Burazer, Aleksandra Šajnović, Nebojša Vasić, Milica Kašanin-Grubin, Dragana Životić, João Graciano Mendonça Filho, Predrag Vulić, Branimir Jovančićević (2020)Nikola Burazer, Aleksandra Šajnović, Nebojša Vasić, Milica Kašanin-Grubin, Dragana Životić, João Graciano Mendonça Filho, Predrag Vulić, Branimir Jovančićević. "Influence of paleoenvironmental conditions on distribution and relative abundance of saturated and aromatic hydrocarbons in sediments from the NW part of the Toplica basin, Serbia" in Marine and Petroleum Geology, Elsevier BV (2020). https://doi.org/10.1016/j.marpetgeo.2020.104252
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A Tel Platform Blending Academic And Entrepreneurial Knowledge
... curricula in ever shortening intervals is a solution that is increasingly harder to achieve. Namely, while technology is rapidly developing, changes in academic programs are subject to procedures that are often time-consuming and slow. On the other hand, academic knowledge that graduate ...Ivan Obradović, Ranka Stanković, Jelena Prodanović, Olivera Kitanović. "A Tel Platform Blending Academic And Entrepreneurial Knowledge" in Proceedings of the The Fourth International Conference on e-Learning (eLearning-2013), September 2013, Belgrade, Serbia, Belgrade, Serbia : Belgrade Metropolitan University (2013)
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Flyrock induced by blasting in surface mining
Milanka Negovanović, Lazar Kričak, Snežana Ignjatović, Stefan Milanović, Jovan Marković, Nikola Simić, Rade Šarac (2022)Miniranje predstavlja i dalje najefikasniji i najjeftiniji način eksploatacije velikih količina čvrstih mineralnih sirovina na površinskim kopovima. Energija eksplozije se koristi za fragmentaciju čvrste stenske mase do zahtevane granulacije. Pored pozitivnih efekata miniranja, postoje i određeni neželjeni efekti svakog procesa miniranja koji se mogu javiti, a to su: potresi tla, razletanje komada stene, vazdušni udari, otrovni i zagušljivi gasovi i prašina. Razletanje komada stene je nekontrolisano izbacivanje fragmenata odminirane stenske mase i predstavlja jedan od glavnih izvora materijalne štete ...Milanka Negovanović, Lazar Kričak, Snežana Ignjatović, Stefan Milanović, Jovan Marković, Nikola Simić, Rade Šarac. "Flyrock induced by blasting in surface mining" in Rudarski glasnik, Beograd : Rudarski institut (2022). https://doi.org/10.25075/BM.2022.05
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Stratigraphic implications of the Mio-Pliocene geodynamics in the area of Mt. Avala: new evidence from Torlak Hill and Beli Potok (Belgrade, Serbia)
Mt. Avala is located on the southern margin of the Pannonian basin (SPB), a border zone between the uplifted morphostructures of the Dinarides and Carpathian-Balkanides. Similar to the Pannonian basin, tectonostratigraphic evolution of the Mt. Avala area during the last 23 Ma has is characterized by syn- and post-rifting processes as well as tectonic inversion. Here, we present the results of field investigations of the Miocene‒Pliocene dynamics that led to different spatial positions of the same stratigraphic units (e.g. ...... length (~ 2km) and plotted on a rose diagram (Fig. 17b). The statistical interpretation of the linear features (ori- entation of river valleys, changes of slope angles, and sharp turns of water flows, etc.) as well as the main fault categories separated in the wider area of Mt. Avala (MAROVIĆ & KNEŽEVIĆ ...
... fluvial phase of relief formation began (MAROVIĆ & KNEŽEVIĆ, 1985). During that time, as the uplift of Torlak Hill progressed, the Zavojnička Reka changes its flow from SE-NW and turns to- wards the E-NE, away from Torlak. This activity led to the for- mation of the new, local structure along which the ...
... MAROVIĆ, M., DJOKOVIĆ, I., KNEŽEVIĆ, S., RUNDIĆ, Lj., MITROVIĆ, S., ŠUMAR, M. & TOLJIĆ, M. (1995): Principal geodynamic stages and paleogeographic changes in southeastern Peripannonian realm of Neogene and Quaternary.‒ Proc. XV Congress C.B.G.A., Geol. Soc. Greece, Athens, sp. publ., 4/1, 69‒73. MAROVIĆ ...Ljupko Rundić, Meri Ganić, Slobodan Knežević, Dejan Radivojević, Miloš Radonjić. "Stratigraphic implications of the Mio-Pliocene geodynamics in the area of Mt. Avala: new evidence from Torlak Hill and Beli Potok (Belgrade, Serbia)" in Geologia Croatica (2019). https://doi.org/10.4154/gc.2019.11
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Nonequilibrium athermal random-field Ising model on hexagonal lattices
Svetislav Mijatović, Dragutin Jovković, Đorđe Spasojević. "Nonequilibrium athermal random-field Ising model on hexagonal lattices" in Physical Review E, American Physical Society (APS) (2021). https://doi.org/10.1103/PhysRevE.103.032147
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A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)
... MEKERK, F.A. (1993) A phased approach to mine dewatering. Mine Water and Environment, 12 (1), pp. 27-33. NIEDBALSKA, K. et al. (2011) Modelling of changes of hydrodynamic conditions in the aquatic environment of the Maczki-Bór sand pit due to the fact of planned closure of mining operations (NE part ...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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Mine ventilation system planning using genetic algorithms
The most common problem in contemporary mining practice related to the planning and analysis of ventilation systems is the optimization of partially regulated air distribution in mine ventilation networks. This paper presents a two step optimization procedure for partly regulated air distribution in mine ventilation networks. The first step is the determination of air distribution in all branches using the well known Hardy-Cross method. In the second step the distribution and parameters of air flow regulators with minimum engaged ...coal, lignite, and peat; ventilation systems; coal mining; underground mining; ventilation; mathematical models; design; air flow; optimization; calculation methodsNikola Lilić, Ranka Stanković, Ivan Obradović. "Mine ventilation system planning using genetic algorithms" in 6. international symposium on mine planning and equipment selection, Ostrava (Czech Republic), 3-6 Sep 1997, A.A. Balkema, Rotterdam (Netherlands) (1997)
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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 ...... be made if the conditions are true. The conclusions may represent logical deductions about the knowledge base or specifications of how it changes over time. Each rule is a relatively independent module, which made it possible to build the reasoning systems gradually, rule by rule. Figure ...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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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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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