Претрага
225 items
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Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites
Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković (2023)To investigate the effect of synthesis procedure and sintering temperature on the functional properties of perovskite/spinel ceramics, BaTiO3/CoFe2O4 composites were prepared by thermal decomposition, coprecipitation, and microemulsion method, and sintered at 1150°C and 1300°C. The phase composition and morphology of as-prepared powders as well as sintered ceramics were thoroughly examined by X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM) coupled with electron dispersive spectroscopy (EDS). The dielectric and ferroelectric measurements were performed in detail. Generally, the ...Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković. "Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites" in Science of Sintering (2023). https://doi.org/10.2298/SOS220512013S
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Mechanosynthesis and structural characterization of nanocrystalline Ce1–Y O2– (x=0.1–0.35) solid solutions
Martin Fabián, Bratislav Antić, Vladimír Girman, Milica Vučinić-Vasić, Aleksandar Kremenović, Shigeru Suzuki, Horst Hahn, Vladimír Šepelák (2015)A series of nanostructuredfluorite-type Ce1–xYxO2–δ (0rxr0.35) solid solutions, prepared via highenergy milling of the CeO2/Y2O3mixtures, are investigated by XRD, HR-TEM, EDS and Raman spectroscopy. For thefirst time, complementary information on both the long-range and short-range structural features of mechanosynthesized Ce1–xYxO2–δ, obtained by Rietveld analysis of XRD data and Raman spectroscopy, is provided. The lattice parameters of the as-prepared solid solutions decrease with increasing yttrium content. Rietveld refinements of the XRD data reveal increase in microstrains in the host ceria ...Martin Fabián, Bratislav Antić, Vladimír Girman, Milica Vučinić-Vasić, Aleksandar Kremenović, Shigeru Suzuki, Horst Hahn, Vladimír Šepelák. "Mechanosynthesis and structural characterization of nanocrystalline Ce1–Y O2– (x=0.1–0.35) solid solutions" in Journal of Solid State Chemistry, Elsevier BV (2015). https://doi.org/10.1016/j.jssc.2015.06.027
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Towards Sustainable Management of Transboundary Hungarian-Serbian Aquifer
Zoran Stevanović, Peter Kozák, Milojko Lazić, Janos Szanyi, Dušan Polomčić, Balazs Kovács, Jozsef Török, Saša Milanović, Bojan Hajdin, Petar Papić (2011)... annual air temperalure of 11'C and rainfall of 575 mm per year. The whole hydrographic network belongs to the river basin of the Biack Sea. It is assumed that about 99% of surface waters are water flows of a transitory nature, while only about 17o comes from rainfall within the region. The major rivers ...
... The well capacity ranges from 5 to 251s i, depending on geology, applied drilling techniclues, construction materials, well development and other factors 17]. In the past, many wel1s were over-pumped and forced beyond their optimal capacities, which caused them to deteriorate c1uic1dy. Therefore, many ...Zoran Stevanović, Peter Kozák, Milojko Lazić, Janos Szanyi, Dušan Polomčić, Balazs Kovács, Jozsef Török, Saša Milanović, Bojan Hajdin, Petar Papić. "Towards Sustainable Management of Transboundary Hungarian-Serbian Aquifer" in Transboundary Water Resources Management - A Multidisciplinary Approach, Weinheim, Germany : Wiley-VCH (2011): 143-149
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Optimising in electrical energy consumption in mining plants
Snežana Aleksandrović, Vesna Damnjanović, Ilija Jeftenić. "Optimising in electrical energy consumption in mining plants" in 17th International Symposium INFOTEH-JAHORINA 2018, Istočno Sarajevo : Elektrotehnički fakultet, Univerzitet u Istočnom Sarajevu (2018)
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Why classical sequence stratigraphy doesn't work in Pannonian basin?
Dejan Radivojević (2018)... y and structural evolution, Geologica Carpatica, 67, 6, 525–542. ter Borgh, M., Radivojević, D., Matenco, L., 2015. Constraining forcing factors and relative sea‐level fluctuations in semi‐enclosed basins: The Late Neogene demise of Lake Pannon, Basin Research doi: 10.1111/bre.12094. ...Dejan Radivojević. "Why classical sequence stratigraphy doesn't work in Pannonian basin?" in 17th Serbian Geological Congress, Vrnjačka Banja, 17-20 maj 2018, Srpsko geološko društvo (2018)
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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 ...... technical capabilities. Such ап analysis would enable better forecasting ог their operation. Dozer's life оп the open-cast mines is related to numerous factors, where most important ones аге machine's quality, ореганпр conditions, maintenance quality, operating quality, апа others. Empirical data shows ...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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Polyhedral characteristics of the cosalite-type crystal structures
Sabina Kovač, Predrag Dabić, Aleksandar Kremenović, Aleksandar Pačevski, Ljiljana Karanović, Marko V. Rodić, Martina Tribus (2019)Sabina Kovač, Predrag Dabić, Aleksandar Kremenović, Aleksandar Pačevski, Ljiljana Karanović, Marko V. Rodić, Martina Tribus. "Polyhedral characteristics of the cosalite-type crystal structures" in The Canadian Mineralogist, Mineralogical Association of Canada (2019). https://doi.org/10.3749/canmin.1900017
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Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources
Large collections of textual documents represent an example of big data that requires the solution of three basic problems: the representation of documents, the representation of information needs and the matching of the two representations. This paper outlines the introduction of document indexing as a possible solution to document representation. Documents within a large textual database developed for geological projects in the Republic of Serbia for many years were indexed using methods developed within digital humanities: bag-of-words and named ...... software solution, but rather registered in a database and accessible to users. Table 1. A matrix of key words, fields that are searched, and weight factors for query “lignite coal in Tamnava region”. DocId Abstract Appendices Keywords Municipality Title Total 577 4 8 12 24 lignit 8 8 Tamnava 8 4 12 ...
... Databases 7 Query processing on the server side expands the faceted query by creating a matrix of key words, fields that are searched, and weight factors (see Table 1), and then translates this query into SQL (Structured Query Language) form. The query generated in such a way searches the text of the ...
... database that correspond to the selected search facets. Ranking of retrieved documents is performed in descending order of the total sum of weight factors for all fields in which the keywords from the faceted search were found. The keyword matrix and the ranking of retrieved documents for the faceted ...Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović. "Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources" in Trans. Computational Collective Intelligence - Lecture Notes in Computer Science 26, Springer (2017). https://doi.org/10.1007/978-3-319-59268-8_8
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Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining
Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović (2019)... advantage of this method is ease of use, followed by the quality of output data. It relies on the theory of the relative weight determination of the factors in decision-making. It is based on the measurements made by comparing pairs of data, and it depends on the evaluation of experts for defining priority ...
... shows the end collective results. 5. Conclusions The choice of the optimal dozer type and manufacturer is a challenge influenced by multiple factors and criteria. It is necessary to consider all the parameters which influence dozer work in specific conditions when selecting new equipment. The ...
... line shows the end collective results. 5. Conclusions The choice of the optimal dozer type and manufacturer is a challenge influenced by multiple factors and criteria. It is necessary to consider all the parameters which influence dozer work in specific conditions when selecting new equipment. The advantages ...Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović . "Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining" in Energies, MDPI (2019). https://doi.org/https://doi.org/10.3390/en12122245
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Overcoming the Low Oral Bioavailability of Deuterated Pyrazoloquinolinone Ligand DK-I-60-3 by Nanonization: A Knowledge-Based Approach
Jelena R. Mitrović , Branka Divović-Matović, Daniel E. Knutson, Jelena B. Ðoković, Aleksandar Kremenović, Vladimir D. Dobričić, Danijela V. Randjelović, Ivana Pantelić, James M. Cook, Miroslav M. Savić, Snežana D. Savić (2021)Poor water solubility of new chemical entities is considered as one of the main obstacles in drug development, as it usually leads to low bioavailability after administration. To overcome these problems, the selection of the appropriate formulation technology needs to be based on the physicochemical properties of the drug and introduced in the early stages of drug research. One example of the new potential drug substance with poor solubility is DK-I-60-3, deuterated pyrazoloquinolinone, designed for the treatment of various neuropsychiatric ...... following nanocrystal administration. Although results of the nanocrystals’ solubility (Figure 6b) did not promise improved pharmacokinetics, other factors such as permeability enhancement could give rise to better absorption [33]. Moreover, the pH value of the empty and fed Pharmaceutics 2021, 13, ...
... consequence of erratic or slower distribution, depot effect in the body, potential interaction with the brain lipids, or the combination of several factors. The structure of the blood-brain barrier is another piece of the complex puzzle when a drug is intended for brain delivery. Figure 8. Ratio between ...
... [CrossRef] [PubMed] 33. Imono, M.; Uchiyama, H.; Yoshida, S.; Miyazaki, S.; Tamura, N.; Tsutsumimoto, H.; Kadota, K.; Tozuka, Y. The elucidation of key factors for oral absorption enhancement of nanocrystal formulations: In vitro–in vivo correlation of nanocrystals. Eur. J. Pharm. Biopharm. 2020, 146, 84–92 ...Jelena R. Mitrović , Branka Divović-Matović, Daniel E. Knutson, Jelena B. Ðoković, Aleksandar Kremenović, Vladimir D. Dobričić, Danijela V. Randjelović, Ivana Pantelić, James M. Cook, Miroslav M. Savić, Snežana D. Savić. "Overcoming the Low Oral Bioavailability of Deuterated Pyrazoloquinolinone Ligand DK-I-60-3 by Nanonization: A Knowledge-Based Approach" in Pharmaceutics, MDPI, Basel, Switzerland (2021). https://doi.org/10.3390/pharmaceutics13081188
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An Approach to Management Decision Support: The Coal Mine Pljevlja Management Information System
In this paper we describe the approach that has been used in the development of the Management Information System (MIS) in the Coal Mine Pljevlja in Montenegro. The methodology of this approach was based on new information technologies and management techniques which have already been successfully applied in other related fields. Its main goal was to introduce modern management techniques to mining, adapted to specific features of the mining industry, its operations and environment, thus enabling the tactical management ...... Design and planning of these processes in the future needs to be closely integrated into more holistic mining systems, considering all controlling factors and impacts (technical, economic, environmental and social). It is crucial for the mining industry to develop a strategy for information technology ...Božo Kolonja, Ranka Stanković, Filip Vuković, Ivan Obradović. "An Approach to Management Decision Support: The Coal Mine Pljevlja Management Information System" in Proceedings of the Fifteenth International Symposium on Mine Planning and Equipment Selection, Torino, Italy, September 2006, Vol. 1,, Balkema (2006)
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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... the potential to contribute significantly to defining, the genesis of groundwater in karst systems. Groundwater genesis is influenced by various factors such as precipitation Sustainability 2023, 15, 11146. https:/ /doi.org,/10.3390/su151411146 https:/ /www.mdpi.com/journal/sustainability Sust ...
... spatial model data, (C)—3D model of the conduit system of the Beljanica karst aquifer, (D)—Krupaja karst system spatial model detail. All of the factors mentioned above explain the possible groundwater genesis and circulation conditions. However, the genesis of the channel remains unknown, as well ...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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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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GIS Application Improvement with Multilingual Lexical and Terminological Resources
... the latter being very important in highly inflective languages, such as Serbian. 1. Introduction Internationalization is one of the major factors currently influencing the application of geographic information systems (GIS) throughout the world. The research described in this paper is based ...Ranka Stanković, Ivan Obradović, Olivera Kitanović. "GIS Application Improvement with Multilingual Lexical and Terminological Resources" in Proceedings of the 5th International Conference on Language Resources and Evaluation, LREC 2010, Valetta, Malta, May 2010, Valetta, Malta : European Language Resources Association (2010)
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Formative evaluation of e-learning projects with the logical framework approach
... outputs, specific objectives (results), global goals (impacts); c. identification of "conditions" or "assumptions and risks" or "external factors" whose presence is indispensable for the realization of the causal chain. Figure 1: LFM's structure [24] Once filled the LFM, the project ...Roberto Linzalone, Giovani Schiuma, Ivan Obradović, Ranka Stanković. "Formative evaluation of e-learning projects with the logical framework approach" in The Sixth International Conference on e-Learning (eLearning-2015), September 2015, Belgrade, Serbia, Belgrade Metropolitan Univesity (2015)
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Development of integrated fuzzy model for mine management optimization
Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić (2023)... engineering. Decision making. requires the best possible knowledge about all the influencing, parameters of the ore deposit. In addition to natural factors, decisions about the mining: technology to be applied depend on technoeconomic aspects, ensuring of a safe and healthy work environment, and the ...Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić. "Development of integrated fuzzy model for mine management optimization" in Comptes rendus de l'Académie Bulgare des Sciences (2023)
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Conversion of land areas after coal mine closure and reclamation
Otkopavanje uglja površinski i podzemno praćeno je degradacijom zemljišta, promenom formiranja predela i izmenom flore i faune. Od velikog značaja je razvoj novih naučno utemeljenih pristupa obnovljanje antropogeno poremećenih predela zasnovanih na formiranju rekultivacionih i rudarskih tehnologija. Apsolutno je neophodno obezbediti sveobuhvatno kvalitetno očuvanje zemljišnih i vodnih resursa i odrediti rekultivisano zemljište za novu namenu. U ovom članku je dat pregled najpopularnijih metoda rekultivacije zemljišta i mogućnosti rekultivacije zemljišta nakon završetka rekultivacije i zatvaranja rudnika uglja.... the coal industry in the future, which requires more resources and effort. Further significant progress in the reclamation is related to several factors: • basic research, application of the sands, which would be the reclamation friendly and neutral for the natural environment, application of the ...Radmila Gaćina, Bojan Dimitrijević, Sanja Bajić. "Conversion of land areas after coal mine closure and reclamation" in 9th International conference mining and environmental protection MEP 23 Proceedings, Sokobanja, 24-27.05.2023., Belgrade : University of Belgrade - Faculty of mining and geology (2023)
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Hidrogeohemijska valorizacija esencijalnih mikroelemenata mineralnih voda Srbije
Jana S. Stojković (2013-09-25)Mineralne vode još od davnina privlače pažnju ljudi i to kako u pogledu istraživanja iproučavanja, tako i u pogledu njihovog iskorišćavanja. Naročito je važno poznavanjesadržaja mikroelemenata u njima, jer su to komponente njihovog hemijskog sastavakoje ih odvajaju od tzv. „običnih“ malomineralizovanih voda.U ovom radu proučavani su odabrani esencijalni mikroelementi (fluor, bor, litijum,kalijum, stroncijum i silicijum), u mineralnim vodama Srbije, pri čemu je analiziranopreko 130 uzoraka mineralnih voda iz različitih geoloških sredina, to jest hidrogeološkihrejona. Cilj ovog istraživanja bio je ...esencijalni mikroelementi, faktori migracije, zakonomernosti rasprostranjenja, hidrogeohemijski procesi, multivarijantna statistička analiza, mineralne vode Srbije... of 14 chemical parameters measured on 110 mineral water samples from Serbia, three factors were extracted, which explain 67.4 % of the total variance in the analyzed dataset. The interpretation of obtained factors has Jana S. Stojković Doktorska disertacija vii indicated several hydrog ...
... . By systematizing the results of this research the following conclusions have been drawn: The joined effect of all three extracted factors results in appearance of higher concentration of all analyzed microelements. This is the case in thermal carbonated mineral waters appearing in ...
... The assumption about paragenesis of the considered microelements has been confirmed by this fact. The domination of each of the extracted factors has been caused by the position of the important geological structures on the Serbian territory. The first factor is dominant at mineral water ...Jana S. Stojković. "Hidrogeohemijska valorizacija esencijalnih mikroelemenata mineralnih voda Srbije" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2013-09-25)
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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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A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)
... the porous medium and hydrodynamic state of aquifer flow, - aquifer regime, which is determined by certain laws, phenomena and distribution of factors, - water balance components, - boundary conditions (inflow into and outflow from the model), and - initial conditions, determined by the piezometric ...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