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226 items
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Analiza nosivosti vertikalno opterećenog šipa za potrebe izgradnje petlje „Merošina 1“ na autoputu E-80 deonica: Niš – Merošina
U Srbiji je počela izgradnja autoputa E-80 koji će predstavljati saobraćajno čvorište zapadnog Balkana i biće deo glavne regionalne transportne mreže jugoistočne Evrope. Njegova ukupna dužina kroz Srbiju iznosi 77 km, a prva deonica u dužini od 5.5 km je završena i puštena u saobraćaj krajem jula 2023. god. To je prva od četiri deonice Sektora 1 čija je dužina 32.65 km. U sklopu petlje „Merošina 1“ izgrađen je nadvožnjak koji je oslonjen na devet stubnih mesta na međusobnom ...Dragoslav Rakić, Nikola Božović, Miloš Stevanović, Milan Bogdanović. "Analiza nosivosti vertikalno opterećenog šipa za potrebe izgradnje petlje „Merošina 1“ na autoputu E-80 deonica: Niš – Merošina" in Geotehnički aspekti građevinarstva i zemljotresno inženjerstvo – Vrnjačka Banja, 01-03. novembar 2023., Beograd : Savez građevinskih inženjere Srbije (2023)
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Mineralogical Discrimination between Authentic and Recent Imitations of Pottery Manufacture in Zlakusa, Serbia
Maja Milošević, Mihovil Logar, Biljana Đorđević. "Mineralogical Discrimination between Authentic and Recent Imitations of Pottery Manufacture in Zlakusa, Serbia" in Nordic Clay Meeting/3rd Symposium Clays & Ceramics 2021, The Latvian Clay Science Society (2021)
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Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit
... condition: if the radius of charge , and distance from the blasting site to the monitoring point r increase in the same or approximately the same ratio, the rock mass oscillation velocity V remains the same [6]. Here we cite second way of rock mass oscillation velocity equation derivation. If, in ...
... 00[m/ s] , • velocity of transverse elastic waves C, = 2852.67[m/ s] ; = 62.46[GN/m2], • dynamic elasticity modulus FE„ lin • „dynamic Poisson' ratio //„„ — 0.39|iGN/m2] . 6.2 Method of blasting in the open pit Kovilovača Measurements of seismic shocks in the open pit Kovilovača were performed ...Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac. "Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit" in 9th International Conference Mining and Environmental protection MEP, 24 – 27 May 2023, Sokobanja, Serbia, Belgrade : University of Belgrade-Faculty of mining and geology (2023)
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Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry
Self-engineering is a relatively new branch of knowledge that aims to understand how systems could “autonomously” re-configure or repair themselves without the intervention of the operators. A direct field of application is within the maintenance spectrum. Having systems or machines capable of self-detecting or even self-repairing could represent a game-changer, in capital asset fields such as the mining industry in particular. This paper aims to investigate the possible benefits and challenges of self-engineering / self-maintenance concerning mining machines, specifically bucket-wheel ...self-engineering, self-maintenance, maintenance operations, mining industry, bucket-wheel excavator, gearbox revitalization... technical perspective and from a financial perspective. Figure 2 shows a Pareto analysis of the BWE systems ranked by failure frequency/cost ratio. The first group of systems are the bearings in the gearbox. In theory, designed for infinite life without displaying an increasing failure rate; ...
... should thus be replaced following a preventive approach instead of corrective maintenance. Fig. 2. BWE systems ranked by failure frequency/cost ratio The second group of systems are the shafts of the digging gearbox. In general, the shafts are designed in such a way that they will not fail due ...Steven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti. "Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry" in SSRN Electronic Journal, Elsevier BV (2021). https://doi.org/10.2139/ssrn.3945979
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Business Models for Small-scale Biomass Projects Development
Biomass is recognized as the most promising renewable energy source in Serbia. The share of biomass in Serbian final energy consumption is over 10%, but mostly related to traditional use in stoves and ovens. One of the main obstacles for wider implementation of contemporary biomass facilities is the inexperience of consumers and stakeholders in the implementation of “innovative” business models, especially in the cases of small-scale projects. In this paper, three different business models (public utility company, energy cooperative ...Dejan Ivezić, Miodrag Gluščević, Marija Živković. "Business Models for Small-scale Biomass Projects Development" in 19th International Conference on Thermal Science and Engineering of Serbia, Niš : Faculty of Mechanical Engineering (2019)
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Polymorphism and photoluminescence properties of K3ErSi2O7
alkalni silikati elemenata retkih zemalja, silikati lantanoida, polimorfizam, fotoluminescencija, kristalna struktura... composition of a pure single crystal. After crystal polishing, the semiquanti- tative chemical analysis shows a K:Er:Si ratio of 3.05:1.04:1.91 for polymorph 1, and the same ratio for polymorph 2 is 3.01:1.05:1.94, what is in good agreement with the results of the single-crystal X-ray structure analysis ...
... of polymorph 1: Er2O3 (Sigma–Aldrich, 99.99%), SiO2 (Merck, p.a.) and KF (Centrohem, 99%). 0.1647 g of a mixture of Er2O3 and SiO2 in a 1:4 molar ratio was measured and then 2 g KF was added. The resulting mixture was homogenized in an agate mortar research papers 2 of 7 Dabić et al. � Polymorphism ...
... of polymorph 1: Er,03 (Sigma-Aldrich, 99.99%), SiO. (Merck, p.a.) and KF (Centrohem, 99%). 0.1647 g of a mixture of Er,O03 and SiO, in a 1:4 molar ratio was measured and then 2 g KF was added. The resulting mixture was homogenized in an agate mortar 2 of 7 Dabié et al. - Polymorphism of K3ErSizO7 Acta ...Predrag Dabić, Marko G. Nikolić, Sabina Kovač, Aleksandar Kremenović. "Polymorphism and photoluminescence properties of K3ErSi2O7" in Acta Crystallographica Section C Structural Chemistry, International Union of Crystallography (IUCr) (2019). https://doi.org/10.1107/S2053229619011926
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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 ...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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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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Mineralogical study of clays from Dobrodo, Serbia, for use in ceramics
... for the plastic limit and workability of soils. Proceedings Institution of Civil Engineers, 162 (3), 175–185. Barnes G.E. (2013a) An apparatus for the determination of the workability and plastic limit of clays. Applied Clay Science, 80–81, 281–290. Barnes G.E. (2013b) The Plastic Limit and Workability ...
... pure kaolinite, but lower CEC values than bentonite clays (>70 mmol 100 g–1). Plasticity and toughness The liquid limit (LL) of the samples varies from 32.4% to 53.6% and the plastic limit (PL) varies from 13.8% to 30.2%. Clays with a plasticity index (PI) <10% are not appropriate for building-related ...
... bodies depends on the Fe oxide content, and the limit of 3 wt.% of Fe2O3 has been found to be the value that sepa- rates light from dark firing bodies (Dondi et al., 2014). Fig. 8. Holtz & Kovacs (1981) diagram of the studied samples. LL = liquid limit; PI = plasticity index. Clay Minerals 375 Summary ...Maja Milošević, Predrag Dabić, Sabina Kovač, Lazar Kaluđerović, Mihovil Logar. "Mineralogical study of clays from Dobrodo, Serbia, for use in ceramics" in Clay Minerals, Mineralogical Society (2019). https://doi.org/10.1180/clm.2019.49
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Hydrothermal Synthesized and Alkaline Activated Carbons Prepared from Glucose and Fructose—Detailed Characterization and Testing in Heavy Metals and Methylene Blue Removal
Sanja Krstić, Milan Kragović, Maja Pagnacco, Vladimir Dodevski, Branka Kaluđerović, Miloš Momčilović, Ivica Ristović, Marija Stojmenović (2018)glukoza, fruktoza, аktivni ugalj, hidrotermalni tretman, aktivacija hidroksida, teški metali, metilen plavoSanja Krstić, Milan Kragović, Maja Pagnacco, Vladimir Dodevski, Branka Kaluđerović, Miloš Momčilović, Ivica Ristović, Marija Stojmenović . "Hydrothermal Synthesized and Alkaline Activated Carbons Prepared from Glucose and Fructose—Detailed Characterization and Testing in Heavy Metals and Methylene Blue Removal" in Minerals, MDPI (2018)
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Concepts for Improving Machine Learning Based Landslide Assessment
... case study MCDA method produced slightly better results than the SVM method. The study of Park et al. (2013) compared the abilities of frequency ratio (FR), analytic hierarchy process (AHP), logistic regression (LR), and artificial neural network (ANN) for LAM for the Inje area (Korea). Their results ...
... cross-correlating attributes against the class label and making a reduced subset of attributes. Several ranking techniques are very popular in LAM: gain ratio, information gain (IG), principal components, etc. All these are based on entropy values, which determines how informative (useful) an attribute is ...
... learning techniques. Geoderma 305:314– 327 Choi J, Oh HJ, Lee HJ, Lee C, Lee S (2012) Combining landslide susceptibility maps obtained from frequency ratio, logistic regression, and artificial neural network models using ASTER images and GIS. Eng Geol 124:12–23 Chung CJF, Fabbri AG (2003) Validation of ...Miloš Marjanović, Mileva Samardžić Petrović, Biljana Abolmasov, Uroš Đurić. "Concepts for Improving Machine Learning Based Landslide Assessment" in Natural Hazards GIS-based Spatial Modeling Using Data Mining Techniques, Advances in Natural and Technological Hazards Research, volume 48, Springer Nature Switzerland AG 2019 (2019). https://doi.org/10.1007/978-3-319-73383-8_2
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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 ...... — Rp - production gas-oil ratio (GOR), (m*?/m*) — Rs- gas solubility factor in oil, (m?/m*) — Bg - gas formation volume factor, (m3/m?) As seen in the previous equation, volumetric efficiency is a function of the ratio of free gas to oil, 1.e., the gas-oil ratio (Rp). The higher the Rp, the ...
... performed when the dynamic pressure is lower than the saturation pressure (presence of gas at the pump intake) and the ability to achieve a high ratio of discharge to suction pressure, make these pumps very efficient under any well conditions. [5] Insert pumps can be classified based on their seating ...
... Name Plate Power\ 0.44828 w Water Salinity 6221.83____ppm WorkDone ByPump|9050.19 — |N _E pre== Work Done By Polished Rod| 33699.1 — |N Gas Oil Ratio, 25.8 Sm3/Ssm3 }| — — Top Rod % Of Goodman Diagram, 19.8874 percent [ EGG e Top RodLoadmg 30.7254 | percent IEnner Stroke Rate, Calculate Production ...Ana Ponoćko. Design of a sucker rod pumping system, 2024
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Structural characterization of traditional pottery produced from local clay, Rujište (Ražanj, Central Serbia), in an effort to preserve its geoheritage
Maja Milošević, Biljana Đorđević, Alena Zdravković . "Structural characterization of traditional pottery produced from local clay, Rujište (Ražanj, Central Serbia), in an effort to preserve its geoheritage" in 9th International Conference Mineralogy and Museums, Sofia, Bulgaria, Earth and Man National Museum and Bulgarian Mineralogical Society (2021)
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Characterization and Environmental Evaluation of Recycled Aggregates from Construction and Demolition Waste in Belgrade City Area (Serbia)
Filip Abramović, Miroslav Popović, Vladimir Simić, Vesna Matović, Radmila Šerović. "Characterization and Environmental Evaluation of Recycled Aggregates from Construction and Demolition Waste in Belgrade City Area (Serbia)" in Materials, MDPI AG (2024). https://doi.org/10.3390/ma17040820
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Laboratory Testing of Nanosilica- Reinforced Silicate and Polyacrylamide Gels
Irina Zahirovic, Dušan Danilović, Milica Šuput Vranjin, Miloš Tripković. "Laboratory Testing of Nanosilica- Reinforced Silicate and Polyacrylamide Gels" in SPE Journal (2023)
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Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia
Bojan Kostić, Pavle Tančić, Natalija Batoćanin. "Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia" in Geological Quarterly, septembar 2024, Polish Geological Institute - National Research Institute (PGI-NRI) (2024). https://doi.org/10.7306/gq.1752
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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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Anisotropic grossular–andradite garnets: Evidence of two stage skarn evolution from Rudnik, Central Serbia
This paper presents LA-ICP-MS data for garnets from the Rudnik skarn deposit (Serbia), which range from Grs45–58Adr40–52Alm2–3 in the core and Adr70–97Grs2–29Sps1 in the rim displaying anisotropy and zoning. In spite of wide compositional variations the garnets near the end-member of andradite (Adr > 90) are generally isotropic. Fe-rich rims exhibit LREE depletion and flat HREE pattern with weak negative Eu anomaly, including higher As and W contents. On the other side, the Fe-poorer core shows flat REE pattern ...Bojan Kostić, Danica Srećković-Batoćanin, Petyo Filipov, Pavle Tančić, Kristijan Sokol. "Anisotropic grossular–andradite garnets: Evidence of two stage skarn evolution from Rudnik, Central Serbia" in Geologica Carpathica, Central Library of the Slovak Academy of Sciences (2021). https://doi.org/10.31577/GeolCarp.72.1.2
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Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia
Bojan Kostić, Pavle Tančić, Natalija Batočanin. "Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia" in Geological Quarterly, Polish Geological Institute - National Research Institute (PGI-NRI) (2024). https://doi.org/10.7306/gq.1752
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The influence of Al3+ ion on porcine pepsin activity in vitro
Vesna M. Pavelkić, Kristina R. Gopčević, Danijela Z. Krstić, Marija A. Ilić. "The influence of Al3+ ion on porcine pepsin activity in vitro" in Journal of Enzyme Inhibition and Medicinal Chemistry, Informa UK Limited (2008). https://doi.org/10.1080/14756360701841095