Претрага
2747 items
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Ефикасност дистрибуције и коришћења природног гаса у домаћинствима
Dejan Brkić (2010-03-30)Природни гас ће се у будућности све више користити као енергент за подмиривање грејних потреба становништва у српским градовима. Стога је потребно изнаћи најповољнији начин употребе природног гаса. Природни гас се може користити за подмирење грејних потреба становништва на два дијаметрално супростављена начина, и то директно, тако што би се гас директно уводио у зграде путем дистрибутивног система за снабдевање гасом и затим сагоревао у гасном котлу којим је сваки стан опремљен (гасни дистрибутивни систем), или индиректно, тако што ...prirоdni gаs, distribuciја gаsа,grејаnjе, cеvоvоdi, cеvоvоdnе mrеžе,fаktоr trеnjа pri prоtоku fluidа,urbаnizаm... 1971. Hybrid method for the solution of piping networks. Proc. IEE. 113, 1607‐1612. (на енглеском) 145. Hayes, B., 2005. Why w? American Scientist 93 (2), 104‐108. (на енглеском) 146. Herwig, H., Gloss, D., Wenterodt, T. 2008. A new approach to understanding and modelling the influence of wall rou ...
... nalysis. Journal of Hydraulics Division of American Society of Civil Engineers 94, 219–234. (на енглеском) 253. Shan, H., Zhang, Z., Nieuwstadt, F.T.M. 1998. Direct numerical simulation of transition in pipe flow under the influence of wall disturbances. International Journal of Heat and Fluid ...
... ed for calculation of gas distribution networks with loops of conduits. Hardy Cross developed a numerical method for calculating flow and pressure distribution in a looped network. This method also has been widely used in modeling of waterworks with ring‐like structures of conduits in muni ...Dejan Brkić. "Ефикасност дистрибуције и коришћења природног гаса у домаћинствима" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2010-03-30)
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Groundwater resources for drinking water supply in Serbia´s Southeast Pannonian basin
Dušan Polomčić, Bojan Hajdin, Marina Ćuk, Petar Papić, Zoran Stevanović. "Groundwater resources for drinking water supply in Serbia´s Southeast Pannonian basin" in Carpathian Journal of Earth and Environmental Sciences (2014)
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Spatial assessment of the areas sensitive to degradation in the rural area of the municipality Čukarica
Nature and Landscape Conservation, Soil Science, Agronomy and Crop Science, Water Science and TechnologyNatalija Momirović, Ratko Kadović, Veljko Perović, Miloš Marjanović, Aleksandar Baumgertel. "Spatial assessment of the areas sensitive to degradation in the rural area of the municipality Čukarica" in International Soil and Water Conservation Research, Elsevier BV (2019). https://doi.org/10.1016/j.iswcr.2018.12.004
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Smanjenje sleganja plitkih temelja primenom mikrošipova
Slobodan Ćorić, Dragoslav Rakić (2021)Mikrošipovi su šipovi malog prečnika koji se grade tako što se u tlu specijalni postupkom formira bušotina koja se zatim armira i injektira. Njihov prečnik je najčešće 150 – 300 mm, a dužina može da bude i više desetina metara. Mikrošipovi mogu da se grade u svim vrstama tla i mogu da budu vertikalni i kosi. Oni se, stoga, koriste kao zamena za konvencionalne šipove i ankere. Primena mikrošipova u fundiranju predstavlja jedan savremeni način izgradnje i sanacije temelja/objekata. ...Slobodan Ćorić, Dragoslav Rakić. "Smanjenje sleganja plitkih temelja primenom mikrošipova" in Zbornik radova međunarodno naučno-stručnog savetovanja Zemljotresno inženjerstvo i geotehnički aspekti građevinarstva, Vrnjačka banja, 3-5. novembar 2021., Beograd : Savez građevinskih inženjera Srbije (2021)
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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... process of measuring the cross-section of the underground roadways, certain measurement errors can occur (conditioned by the error of the measurement method, instrumental error, personal error by the operator of the instrument, or the error due to the working environment itself), the nature of fuzzy time ...
... process of measuring the cross-section of the underground roadways, certain measurement errors can occur (conditioned by the error of the measurement method, instrumental error, personal error by the operator of the instrument, or the error due to the working environment itself), the nature of fuzzy time ...
... duration time and costs of reparation with respect to forecasted deforma- tions. Future research will be focused on carrying an in situ measuring of the deformations in an underground mine to quantify the quality of the method. Furthermore, the focus will be on the making of a 3-D model of gate road support ...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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Replica of the “Great Triangle Gold Nugget” Belonging to Belgrade University Collection, Gilded or Not?
... darken by the time it was assumed that the model is gilded. Material and method Chemical composition of the gypsum model surface was carried out in the Laboratory for SEM, Faculty of Mining and Geology, University of Belgrade, using a JEOL JSM-6610LV scanning electron microscope, coupled ...
... f.bg.ac.rs Introduction The Collection of Rocks and Minerals, Faculty of Mining and Geology, the University of Belgrade in Serbia, has been holding over a hundred years the gypsum model of triangular shape that represents the replica of one of the world’s largest native gold nugget weighing ...
... Collection of Rocks and Minerals, is part of old and numerous mineral collection which numbered 1525 samples donated by the St. Petersburg’s State Mining Institute of the empress Catherine II (precursor of Saint Petersburg State University) to the Mineralogical Cabinet of Great School of Belgrade ...Alena Zdravković, Maja Milošević, Ivana Jelić. "Replica of the “Great Triangle Gold Nugget” Belonging to Belgrade University Collection, Gilded or Not?" in 8th Mineral Sciences in the Carpathians Conference, Acta Mineralogica-Petrographica, Miskolc, Hungary, Department of Mineralogy, Geochemistry and Petrology, University of Szeged, Szeged, Hungary (2021)
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Cultural Heritage and Protection of Hand-Wheeled Pottery Manufacture in Western Serbia: Characteristics of Zlakusa Pottery Based on Sem-Eds and Optical Microscopy
... traditional coiling method on a hand rotated wheel, while sample 2 was made with the application of a modern mould technique. A microscopic examination of the thin sections revealed a uniform mineral composition. No significant differences were observed regarding the inner sections of the pots and ...
... higher amount of calcite grains. EDS analysis gives clear differences in the chemistry of the samples. Sample 1 has a higher content of most investigated elements when compared to sample 2, except K and Ca. Amount of K and Ca elements could indicate the presence of a higher amount of illite minerals ...
... the obtained knowledge in the preservation of this type of cultural heritage in Serbia. Results and discussion Clay paste is a mixture of raw clays, consisted of kaolinite/halloysite, illite and smectite minerals followed with smaller amounts of quartz, feldspar and iron oxy/hydroxides ...Milošević Maja, Zdravković Alena, Đordjević Biljana, Jelić Ivana. "Cultural Heritage and Protection of Hand-Wheeled Pottery Manufacture in Western Serbia: Characteristics of Zlakusa Pottery Based on Sem-Eds and Optical Microscopy" in 8th Mineral Sciences in the Carpathians Conference, Acta Mineralogica-Petrographica, Miskolc, Hungary, Department of Mineralogy, Geochemistry and Petrology, University of Szeged, Szeged, Hungary (2021)
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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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Процјена хазарда и ризика од клизишта за различите нивое просторног планирања у Републици Српској, БиХ
Цвјетко С. Сандић (2022)Територија Републике Српске је у посљедних десетак година веома угрожена активирањем нових и реактивирањем старих клизишта. Она својим дјеловањем наносе огромне материјалне штете, па и људске жртве, те је неопходно озбиљније третирање и дјеловање у борби са овим природним хазардом. Чест проблем јесте одговорност, тј. надлежност институција из ове области и недостатак у законској регулативи која готово никако или само површно обрађује област хазарда и ризика од клизишта. Усљед непостојања праксе и усвојених методологија које су у примјени у свијету, циљ ...Цвјетко С. Сандић. Процјена хазарда и ризика од клизишта за различите нивое просторног планирања у Републици Српској, БиХ, Београд : [Ц. Сандић], 2022
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Identification of the Best Available Renewable Energy Source for Electricity Production in Serbia
Around 2/3 of electricity production in Serbia originates from coal-fired thermal power plants. The most significant domestic coal deposits are lignite deposits, a type of low -quality coal that causes negative health, climate and environmental impacts during the combustion. To reduce those negative impacts on domestic electricity production and to promote environmental awareness, the Serbian Energy Sector Development Strategy and the National Action Plan for Use of Renewable Energy Sources indicate the plan for increasing the share of ...Strategija obnovljive energije, Održiva energija, Proizvodnja električne energije, Solarna energija, Biomasa, Hidroenergije, Energija vetra... ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Abstract A r ound 2/3 of electricity production in Serbia ...
... Sector Development Strategy and the National Action Plan for Use of Ren ewable En ergy Sources in dicate the plan for in creasing the share of r en ewable energy sou r ces (RES) in electricity production. Serbia is obliged to reach 27% of the gross energy final con sumption prov ided from the RES u ...
... 2023-10-14 04:10:32 Identification of the Best Available Renewable Energy Source for Electricity Production in Serbia Boban Pavlović, Dejan Ivezić, Marija Živković Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Identification of the Best Available Renewable Energy ...Boban Pavlović, Dejan Ivezić, Marija Živković. "Identification of the Best Available Renewable Energy Source for Electricity Production in Serbia" in Conference on Sustainable Development of Energy, Water and Environment Systems, Sarajevo, 28.6.-2.7.2020., Faculty of Mechanical Engineering and Naval Architecture, Zagreb (2020)
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Аnaliza mogućnosti povećanja nagiba završne kosine površinskog kopa “Podbraćan”
Vladimir Čebašek, Veljko Rupar (2018)Eksploatacijom boksita iz ležišta "Podbraćan" formiran je površinski kop sa maksimalnom visinom zavšne kosine od 280 m. Redovnom kontrolom stabilnosti trenutnog stanja kosina površinskog kopa utvrđeno je da faktor sigurnosti iznosi Fs = 1.71 – 1.85, a što je ukazalo da postoji mogućnost povećanja nagiba kosine. U radu je prikazan postupak analize mogućnosti povećanja nagiba završne kosine površinskog kopa "Podbraćan".Vladimir Čebašek, Veljko Rupar. "Аnaliza mogućnosti povećanja nagiba završne kosine površinskog kopa “Podbraćan”" in Mining and Geology Today, II international symposium, Belgrade, 04 - 05.12.2018., Rudarski institut, Balkanska akademija nauka, Akademija inženjerskih nauka Srbije (2018). https://doi.org/10.25075/SI.2018.17
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Damage quantification of built stone on Dark Gate (Belgrade, Serbia): sample of damage index application for decay rate evaluation
The Dark Gate is the monument of culture, part of the cultural and historical complex of the Belgrade Fortress. It is constructed of limestone blocks that after 270 years of exposure to environmental conditions and different anthropogenic influences show wide ranges of decay forms. During 2007, detail registration of all built limestone microfacies and weathering forms was done using tools of monument mapping. A correlation scheme ‘‘intensity– damage category’’ was made according to the type, intensity, and distribution of ...... present appearance of the gate anthropogenic factor has undoubted influence. The selected mode of cleaning in the past has surely contributed to the increase loss of stone material from block's surface. Because of that, the state of the gate in 2007 provided an initial level of concern and served ...
... provides assessment of the building as a whole and treats it as a product rather than the sum of its individual parts (Smith and Prikry1 2007; McCabe et al. 2007). In the field of stone conservation, monument mapping method is generally accepted as an essential part of con- dition survey ...
... 53–61 Kukela A, Seglins V (2011) Simplified method of assessment of weathering on historical stone monuments: An example of El- Merdani mosque, Cairo, Egypt. J Earth Sci Eng: 8290 Laurenzi Tabasso M (2004) Products and methods for the conserva- tion of stone: problems and trends, In: Kwiatkowski ...Maja Franković, Nevenka Novaković, Vesna Matović. "Damage quantification of built stone on Dark Gate (Belgrade, Serbia): sample of damage index application for decay rate evaluation" in Environmental Earth Sciences, Springer Science and Business Media LLC (2015). https://doi.org/10.1007/s12665-014-3843-z
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The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers
One of the most important prerequisites for the successful operation of the open-cast lignite mine is to carry out all the auxiliary works timely with the necessary quality. The most important and most commonly used auxiliary machines are bulldozers. Engaging time of bulldozers use is in direct relation with the coefficients of the time and capacity utilization of the continuous system for the excavation of coal and tailings, which indicates their importance. More than 100 bulldozers have been hired ...... than this value than should be more of the machines in the fleet of the open cast mine, thus increasing the costs. On the other hand, insufficient number of machines (dozers) will result in reduced execution of auxiliary operations, with influence on efficiency of continuous systems. Below is an example ...
... Cost Capital Cost vW Time of Use Figure 3. The economic life of the machine, based on the minimal cost method (1) Hourly ownership costs and operational costs for dozer could vary significantly. Parameters impacting these costs are: type of job performed, costs of fuel and lubricants, transportation ...
... recommended method for evaluation of hourly ownership and operational costs, including data on auxiliary machines (Caterpillar and Komatsu methods). Integration of this information with operational conditions will enable reliable evaluation. Total costs, i.e. specific cost per moto hour is the sum of following ...Dragan Ignjatović, Predrag Jovančić, Stevan Đenadić, Ivan Janković, Ivica Ristović. "The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers" in 7th International Symposium Mining and Environmental Protection, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2019)
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Mineralogical Discrimination between Authentic and Recent Imitations of Pottery Manufacture in Zlakusa, Serbia
... 380 - 1000 nm range. A standard method was used to determine the water absorption of the investigated shreds of pottery (SRPS ISO 10545-3) reduced to the same dimensions. Based on the obtained results of tested samples of clay pottery, there are a couple of conclusions. Observed difference ...
... University of Latvia Inga Jurgelāne Riga Technical University Jūlija Karasa University of Latvia Solvita Kostjukova Alina Olita Medne Riga Technical University Rūta Ozola-Davidāne University of Latvia Valdis Segliņš University of Latvia Ilze Vircava Latvia University of Life ...
... traditional coiling and hand-wheel manufacture of pottery with raw clay from the local source are characteristic for Zlakusa (western Serbia), which is on the UNESCO Representative List of the Intangible Cultural Heritage of Humanity. Mass production of utilitarian ceramics and pottery items occurred ...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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Advancing Sentiment Analysis in Serbian Literature: A Zero and Few-Shot Learning Approach Using the Mistral Model
Ova studija predstavlja analizu sentimenta srpskih starih romana iz perioda 1840-1920, koristeći veliki jezički model (LLM) Mistral za tehniku učenja sa zasnovani na takozvanim "zero" i "few-shot" pokušajima. Glavni pristup uvodi inovacije osmišljavanjem istraživačkih upita (promptova) uključuju tekst sa uputstvom za klasifikaciju bez primera i na osnovu nekoliko primera, omogućavajući jezičkom modelu da klasifikuje osećanja u pozitivne, negativne ili objektivne kategorije. Ova metodologija ima za cilj da pojednostavi analizu osećanja ograničavanjem odgovora, čime se povećava preciznost ...Milica Ikonić Nešić, Saša Petalinkar, Mihailo Škorić, Ranka Stanković, Biljana Rujević. "Advancing Sentiment Analysis in Serbian Literature: A Zero and Few-Shot Learning Approach Using the Mistral Model" in Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation, Sofia, Bulgaria, 9-10 September 2024, LREC | COLING (2024)
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Mineralogical and physicochemical characterization of bentonite clay from Svrljig, Serbia
Maja Milošević, Bojan Kostić (2022)... granulometry (pipette method), cation exchange capacity (CEC) and specific surface area (SSA) measurements. The sample consists mostly of a fraction <1 μm (56.1%) with a 9.5% <2 μm, representing a total clay content (65.5%). Coarse grain fraction (>20 μm) is present in a total of 10.5%. When the clay ...
... indicating that the studied clay has a high content of montmoril- lonite and a smaller amount of quartz, carbonates, iron oxy/hydroxides and feldspars. Acknowledgements. Ministry of Education and Science, Republic of Serbia, on realization and financing of scientific research work in 2022, contract No. ...
... ion of layer charge of smectites using methylene blue. 2nd International Geosciences Student Conference. Krakow Poland. Milošević, M., Logar, M. 2014. Smectite clays of Serbia and their application in adsorption of organic dyes. EGU General Assembly 16, EGU2014-1882-1. The 22nd Congress of the ...Maja Milošević, Bojan Kostić. "Mineralogical and physicochemical characterization of bentonite clay from Svrljig, Serbia" in Abstracts XXII International Congress of the Carpathian Balkan Geological Association (CBGA), September 7–11, 2022 Plovdiv, Bulgaria, Софиа : Геологически институт „Акад. Страшимир Димитров“ (2022)
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Optimisation of underground mine decline development system using genetic algorithm
... are replaced in the new version of the software tool, DOT2, by a method based on an understanding of exact solutions to a constrained 3-dimensional path problem. Their approach is based on the minimization of the cost of the decline, where the cost is a combination of both development and haulage ...
... hypothesis used in the optimisation model are as follows: - Location of MPF is fixed; - Location of SBP is allowed to vary; - Location of UMCP is allowed to vary; - Locations of the access points are fixed; - The tonnage of ore to be hauled from each orebody to the surface portal is fixed. ...
... equipment characteristics. The absolute value of the decline slope must be less or equal to the maximum value of the slope that can be handled by loaded mine truck in a safe way. Decline optimisation is concerned of determination of locations of SBP and UMCP. A general design optimisation problem ...Zoran Gligorić, Aleksandar Ganić, Rade Tokalić, Aleksandar Milutinović. "Optimisation of underground mine decline development system using genetic algorithm" in Underground mining engineering, Beograd : Univerzitet u Beogradu – Rudarsko–geološki fakultet (2014)
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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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On the distribution modulo 1 of the sum of powers of a Salem number
Dragan Stankov (2016)It is well known that the sequence of powers of a Salem number θ, modulo 1, is dense in the unit interval, but is not uniformly distributed. Generalizing a result of Dupain, we determine, explicitly, the repartition function of the sequence , where P is a polynomial with integer coefficients and θ is quartic. Also, we consider some examples to illustrate the method of determination.Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomialsDragan Stankov. "On the distribution modulo 1 of the sum of powers of a Salem number" in Comptes rendus Mathematique (2016). https://doi.org/10.1016/j.crma.2016.03.012
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Српски језик у дигиталном добу -- The Serbian Language in the Digital Age
Duško Vitas, Ljubomir Popović, Cvetana Krstev, Ivan Obradović, Gordana Pavlović-Lažetić, Mladen Stanojević (2012)... sibility of the automatic annotation of texts based on an annotated corpus, [49] developed during the 1950s and converted to electronic form in the 1990s. Speech synthesis and recognition is being realised at the Faculty of Technical Sciences of the University of Novi Sad through projects of technological ...
... boards of daily newspapers and edito- rial boards of radio and TV stations, as well as language experts and mother tongue enthusiasts are endeavour- ing to contribute to the preservation of the regularity and purity of Serbian in its written and oral usage. 3.4.4 Response to the rising influence of English ...
... organised in some countries for children of Serbian origin. e need for harmonisation of legal systems and terminology with those in the European Union, the influence of Anglo- American culture in the field of entertainment and the media, as well as the effects of globalisation, are con- tributing to ...Duško Vitas, Ljubomir Popović, Cvetana Krstev, Ivan Obradović, Gordana Pavlović-Lažetić, Mladen Stanojević. "Српски језик у дигиталном добу -- The Serbian Language in the Digital Age" in META-NET White Paper Series, G. Rehm, H. Uszkoreit (eds.), Springer (2012)