Претрага
2351 items
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Approach to operational mine planning: Case study Tamnava West
... problem owing to the variable nature of coal properties (heating value, sulfur, ash), even within the same coal seam. In order to ensure a normal and efficient operation of the power plants fed with coal it is necessary to reduce the variation of the coal and that is done through coal hom ...
... is especially important to have enough of in situ data, and to conduct quality operational planning. The importance of operational planning for coal quality control is stressed by Stevanović et. al. 7. Also due to the complex nature of coal operational planning, usage of specialized commercial ...
... allow less dilution effects and greater recovery of reserves. For the case of Tamnava West minimal minable thickens of coal seam was set to 0,5 m. The final design of benches is done in Minex. Although Minex has module for bench design, due to complex nature of bench geometry for Tamnava ...Dejan Stevanović, Mirjana Banković, Milica Pešić Georgiadis, Ranka Stanković. "Approach to operational mine planning: Case study Tamnava West" in Tehnika, Beograd : Savez inženjera i tehničara Srbije (2014). https://doi.org/10.5937/tehnika1406952S
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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 ...... analysis are usually of a very complex nature. They involve the estimation of numerous interdependent parameters pertaining to the network status, ventilation status, ventilation system stability, air current losses, climate conditions, gas state, fire risk and dangerous dust pollution risk. The ...
... approach bearing in mind the coupled numerical-symbolic nature of the system aimed at solving a hierarchically structured problem. The obtained system structure of the VENTEX system was realized in KAPPA-PC.. References Coad,P., and Yourdon,E., (1991), Object-Oriented Analysis, Second ...
... facts and heuristics which can be represented by means of rules, frames, semantic networks and other formalisms. Since knowledge is the key factor in problem solution and decision making, the quality and usability of an expert system is basically determined by the accuracy and completeness ...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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The Content of Toxic Metals in Agricultural Produce near a Coal Mine: Case Study KCB in Lazarevac, Serbia
Праћење и анализа концентрација токсичних метала (олово и кадмијум) у земљишту и усевима указују на то да пољопривредно земљиште у Србији углавном није загађено, а квалитет земљишта је природно добар. Због тога су таква земљишта погодна за органску пољопривреду. Сви уочени случајеви контаминације токсичним металима су само локалне природе, а резултат су ђубрива и пестицида, комуналног отпада, издувних гасова, оближњих производних објеката, топионица, рудника, јаловишта итд. Локације овог типа морају бити редовно прати и процењује статус земљишта и усева. ...Ana Koprivica, Čedomir Beljić, Boris Vakanjac, Vesna Ristić Vakanjac, Marina Čokorilo Ilić. "The Content of Toxic Metals in Agricultural Produce near a Coal Mine: Case Study KCB in Lazarevac, Serbia" in Minerals, MDPI AG (2018). https://doi.org/10.3390/min8040131
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The influence of alkyl polyglucosides (and highly ethoxylated alcohol boosters) on the phase behavior of a water/toluene/technical alkyl polyethoxylate microemulsion system
Marija Ilic, Franz-Hubert Haegel, Vesna Pavelkic, Dragan Zlatanovic, Snezana Nikolic-Mandic, Aleksandar Lolic, Zoran Nedic (2016)The influence of additives (alkyl polyglucoside, Glucopon 600 CS UP and alcohol ethoxylate C18E100) on the behavior of the water/toluene/Lutensol ON 50 (technical oxoalcohol, i-C10E5) microemulsion system as a function of temperature and composition has been investigated. The phase behavior of the microemulsions was determined by vertical sections through the Gibbs phase prism (fish-like phase diagrams). Alkyl polyglucoside shifts the one phase region to lower temperatures compared with water/toluene/Lutensol ON 50 mixtures. This is contrary to the expectation, considering ...микроемулзија, толуен, алкил полиглукозид, оксоалкохол етоксилат, појачивач ефикасности, „fish“ дијаграми... the extreme hyarophilic nature of the sugar headgroup. The additon of hydrophilic alcoho! ethoxylate (CisEtoo) to the water/toluene/Lutenso! ON 50 system increases the solubiliz- altion capacity of the surfactant, even if the co-surfactant is used in small quan- tities, and shifts the one-phase ...
... (“fish tail” with the phase sequence @1–%) becomes wider and the efficiency of the surfactant mixture increases slightly. With increasing , the “fish tail! unexpectedly moves downward on the temperature scale despite the hydrophilic nature of the sugar surfactant. The efficiency of the surfactant ...
... RESULTS AND DISCUSSION The pseudo-binary phase diagrams of micro- emulsion systems were determined at equal mass fractions of water and toluene (a= 0.5) for two non- ionic surfactants, pure linear CxjEs and technical branched i-Cxo5Es (Lutensol ON 50) in order to find the composition and temperature ...Marija Ilic, Franz-Hubert Haegel, Vesna Pavelkic, Dragan Zlatanovic, Snezana Nikolic-Mandic, Aleksandar Lolic, Zoran Nedic. "The influence of alkyl polyglucosides (and highly ethoxylated alcohol boosters) on the phase behavior of a water/toluene/technical alkyl polyethoxylate microemulsion system" in Chemical Industry and Chemical Engineering Quarterly, National Library of Serbia (2016). https://doi.org/ 10.2298/CICEQ141105015I
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Frequency and Length of Syllables in Serbian
Marija Radojičić, Biljana Lazić, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Ján Mačutek, Lívia Leššová (2019)Basic analyses of several properties of syllables (the rank-frequency distribution, the distribution of length, and the relation between length and frequency) in Serbian is presented. The syllabification algorithm used combines the maximum onset principle and the sonority hierarchy. Results indicate that syllables behave similarly to words as far as mathematical models are concerned, but values of parameters in models for syllables are quite different from those for words.... Rovenchak, A. (2011). Canonical word forms: Menzerath-Altmann law, phonemic length and syllabic length. In: Kelih, E., Levickij, V., Matskulyak, Y. (eds.), Issues in Quantitative Linguistics 2: 136-147. Lüdenscheid: RAM-Verlag. Frequency and Length of Syllables in Serbian 123 Mačutek, J., Wimmer ...
... 18 This hypothesis (now known as the law of brevity) was first formulated for words by Zipf (1935). 19 Ferrer-i-Cancho & Hernández-Fernández (2013) provide Spearman correlations between word frequency and length (measured in the number of letters) in seven languages. The ...
... (2008). Frequency and Length of Syllables in Serbian 117 3. Language material Serbian is a South Slavic language. It has the official status in Serbia (exclusively) and in Bosnia and Herzegovina (as one of three languages, together with Bosnian and Croatian), and the status of a minority ...Marija Radojičić, Biljana Lazić, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Ján Mačutek, Lívia Leššová. "Frequency and Length of Syllables in Serbian" in Glottometrics (2019)
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Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides
... organic contaminants, such as nonionic pesticides. On the other hand, due to the high solubility, pesticides are mobile and could be detected in groundwater. Changing the surface nature of montmorillonite from hydrophilic to hydrophobic is crucial for enhancing the sorption of pesticides. This change in ...
... 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 Call for contributions Clean water and sanitation & Life on land Linking soil mineralogy to soil properties and functions ...
... Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides Lazar Kaluđerović, Zorica Tomić, Rada Đurović-Pejčev, Maja Milošević Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization ...Lazar Kaluđerović, Zorica Tomić, Rada Đurović-Pejčev, Maja Milošević. "Characterization of Natural Clay from Bogovina (Serbia) and Possible Utilization in Sorption of the Herbicides" in Eurosoil2020, online event 2021, Eurosoil, Frontiers Abstract Book (2021)
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Karst aquifer impact on the formation of surface runoff: case study of the Resava River catchment, Serbia
Marina Mitrašinović, Vesna Ristić Vakanjac, Veljko Marinović, Saša Milanović, Ljiljana Vasić, Dušan Polomčić (2022)The paper compares the flow regimes of the Resava River at the gauging stations of the Manasija Monastery (upper course) and the town of Svilajnac (lower course). The hydrological analysis encompasses a multiyear period of monitoring (1982–2020). The water budget and baseflow index are assessed for the catchment areas monitored by the Svilajnac station (683 km2) and the Manasija Monastery station (358k m2), considering the overall monitoring period and characteristic years. The results indicate that the specific runoff in ...... m) and the northwestern part of the Kučaj Mountains (1284 m). The Resava Gorge was formally desig- nated as a protected area in 1955, as part of the Up- per Resava Regional Nature Park. The area hosts several natural features with the status of naturc monumcnts, including Vintovača (nature preserve) ...
... Manasija Monastery and Qav = 4.35 m#/s at Svilajnac) and 2018 (Qav = 4.06 m?*/s at Manasija Monastery and Qav = 4.65 m?*/s at Svilajnac (Figs. 1a, 1b); • The ycar 1994 with a typical low discharge: Qav = 0.58 m*/s (at the Mansija Monastery) and 0.33 m?*/s (at Svilajnac) (Fig. 1c); and • The year 1999 ...
... Monastery (upper course) and the town of Svilajnac (lower course). The ydrological analysis encompasses a multiyear period of monitoring (1982—2020). The water budget and baseflow index are assessed for the catchment areas monitored by the Svilajnac station (683 km?) and the Manasija Monastery station ...Marina Mitrašinović, Vesna Ristić Vakanjac, Veljko Marinović, Saša Milanović, Ljiljana Vasić, Dušan Polomčić. "Karst aquifer impact on the formation of surface runoff: case study of the Resava River catchment, Serbia" in National Conference with International Participation “GEOSCIENCES 2022”, Sofia : Bulgarian geological society (2022)
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Korelacija magnetnog susceptibiliteta i sadržaja metala u flotacijskom jalovištu
Procena metala u rudama, jalovištu i zemljištu se tradicionalno određuje hemijskim metodama kao što su Rengen fluorescentna analiza (XRF), Instrumentalna neutronska aktivaciona analiza (INAA) i Masena spektrometrija induktivno spregnute plazme (ICP-MS). Neke od pomenutih metoda su veoma zahtevne i skupe, te se nametnula potreba ka traženju jeftinijeg alata za brzu procenu prisustva pojedinih metala. Tokom poslednjih nekoliko decenija, mnoge studije su pokazale da su magnetna merenja dovoljno osetljiva da detektuju magnetni signal feromagnetnih materijala, a samim tim i metala ...Filip Abramović, Vesna Cvetkov, Aco Ilić, Dragana Životić. "Korelacija magnetnog susceptibiliteta i sadržaja metala u flotacijskom jalovištu" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
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Jeleč grad- još nepriznati objekat geonasleđa
Остаци средњовековног града Јелеча на једном од врхова планине Рогозне (1262 m), по неким веровањима представљаju купу угашеног вулкана. Рогозна je позната по појавама скарновске Cu–Au минерализације, а трагови рударске активности и важних путева још од античких времена и даље постоје у непосредној околини. О томе сведочи и османски назив за Рогозну: Gümüş Dağ (Сребрна планина). Време изградње Јелеча је непознато. Постоје индиције да је постојао још у 6. веку, али се помиње први пут средином 12. века. Поуздан податак ...Marija Radisavljević, Danica Srećković Batoćanin, Vladan Vidosavljević, Irena Kajtez. "Jeleč grad- još nepriznati objekat geonasleđa" in Zbornik apstrakata, 212. 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022, Srpsko geološko društvo (2022)
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Hydrogeochemistry of Uranium in the Groundwaters of Serbia
Marina Ćuk, Maja Todorović, Petar Papić, Jovan Kovačević, Zoran Nikić. "Hydrogeochemistry of Uranium in the Groundwaters of Serbia" in Uranium - Past and Future Challenges, Springer International Publishing Switzerland (2015). https://doi.org/10.1007/978-3-319-11059-2_89
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Природни потенцијал минералних вода Србије - Natural potential of mineral waters in Serbia
Оливера Крунић (2021)Оливера Крунић. "Природни потенцијал минералних вода Србије - Natural potential of mineral waters in Serbia" in Рационално коришћење земљишта и вода у Србији - Sustainable Use of Land and Water in Serbia- Serbian Academy of Sciences and Arts; Scientific Conferences Volume CXCVII; Department of Chemical and Biological Sciences, Book 19, Српска академија наука и уметности (2021)
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Carbonate rocks on Rudnik
Ljubić Obradović Darivojka, Vasić Nebojša. "Carbonate rocks on Rudnik" in Third International Conference Harmony of nature and spirituality in stone, Kragujevac:Stone Studio Association (2013): 273-274
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Geology of the southern part of the Sava-Vardar zone: new constraints from the Klepa Mts.
... unique opportunity to study the nature and timing of the final closure of the Neotethys Ocean. The Klepa Mountains, situated in the central part of North Macedonia, form a block extending: 5-6 km NNW-SSE and 1-2 km WSW-ENE, reaching a hecight of 1150 m a.s.l. and serving as a prominent landmark ...
... carbonate rocks arc represented by reddish, locally pinkish, or grey, light grey hemipelagic and pelagic biomicrites with rich planktonic and · benthic · foraminiferal associations. and othcr diverse micro- and macrofossil assemblages (calcareous nannoplankton, calcified radiolarians, palynomorphs ...
... which encompasses the Dinaric, Carpathian, and Balkan double-verging Alpine orogenic belt, remains a topic of ongoing debate ({1], [2] and references therein). This orogenic system arose from thc closure of the northern branch of the Neotethys Ocean and subsequent collision-related processes. Key ...Dejan Prelević, Ana Mladenović, Violeta Gajić, Milena Dunčić, Blažo Boev. "Geology of the southern part of the Sava-Vardar zone: new constraints from the Klepa Mts." in Fifth Congress of Geologists of the Republic of North Macedonia, Macedonian Geological Society (2024)
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Haevy minerals in alluvium the river Nera
Vasić Nebojša, Krunić Rajko, Košćal Milan. "Haevy minerals in alluvium the river Nera" in Third International Conference Harmony of nature and spirituality in stone, Kragujevac:Stone Studio Association (2013): 223-234
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Development of a petrographic classification system for organic particles affected by self-heating in coal waste. (An ICCP Classification System, Self-heating Working Group – Commission III)
M. Misz-Kennan, J. Kus, D. Flores, C. Avila, Z. Büçkün, N. Choudhury, K. Christanis, J.P. Joubert, S. Kalaitzidis, A.I. Karayigit, M. Malecha, M. Marques, P. Martizzi, J.M.K. O'Keefe, W. Pickel, G. Predeanu, S. Pusz, J. Ribeiro, S. Rodrigues, A.K. Singh, I. Suárez-Ruiz, I. Sýkorová, N.J. Wagner, D. Životić (2020)Self-heating of coal waste is a major problem in the leading coal-producing and consuming countries, independent of the recent or past coal exploitation history. The phenomenon of self-heating is dependent on many factors such as the properties of organic matter (maceral composition and rank), moisture and pyrite content, climate effects, and storage conditions (shape of the dump or compaction of the coal waste). Once deposited, coal waste undergoes oxidation, which can lead to self- heating with the overall temperatures ...M. Misz-Kennan, J. Kus, D. Flores, C. Avila, Z. Büçkün, N. Choudhury, K. Christanis, J.P. Joubert, S. Kalaitzidis, A.I. Karayigit, M. Malecha, M. Marques, P. Martizzi, J.M.K. O'Keefe, W. Pickel, G. Predeanu, S. Pusz, J. Ribeiro, S. Rodrigues, A.K. Singh, I. Suárez-Ruiz, I. Sýkorová, N.J. Wagner, D. Životić. "Development of a petrographic classification system for organic particles affected by self-heating in coal waste. (An ICCP Classification System, Self-heating Working Group – Commission III)" in International Journal of Coal Geology, Elsevier BV (2020). https://doi.org/10.1016/j.coal.2020.103411
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Formative evaluation of e-learning projects with the logical framework approach
... the E-Learning sector, as many others. In general, and as a first approximation, evaluate means to give, recognize, a value in formal, clear and methodologically rigorous way, to a subject (evaluand) [2]. The evaluation as a process nature, being the set of activities related useful for expressing ...
... results/benefits, due to: intangible nature of the results (learning and knowledge), difficulty of quantifying them in economic, social, cultural terms, heterogeneity of the various benefits delivered. All these criticalities of the EPs requires a higher and better attention to the design phase of ...
... 2. EVALUATION OF PROGRAM AND PROJECTS The scientific debate on the evaluation of projects becomes more and more interesting in light of the large economic investments in projects and programs, and the difficulty of assessing the genuine and effective economic and social returns. This issue ...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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Structures of the Struganik limestone
Gajić Violeta, Vasić Nebojša (2011)Gajić Violeta, Vasić Nebojša. "Structures of the Struganik limestone" in Proceedings / 1th International Conference Harmony of Nature and Spirituality in Stone, 17-18 March 2011, Kragujevac, Kragujevac:Stone Studio Association (2011): 63-75
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Traces of ancient mining in the territory of Serbia
Đoković Ilija, Ilić Aco, Milovanović Dragan. "Traces of ancient mining in the territory of Serbia" in 3rd International Conference Harmony of nature and spirituality in stone, Kragujevac:Stone Studio Association (2013): 283-290
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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. ...... KOVACS et al., 2015 and references therein). Based on these relief data as well as the observed Topčiderska Reka and Zavojnička Reka river flows that are obviously struc- turally controlled (see Figs. 1, 17 and 21), it is reasonable to ar- gue that drainage system and landscape evolution during Pon- ...
... ly, it can be divided into two parts: a composite hilly landscape consisting of the Torlak Hill (310 m) and Mt. Avala (511 m) and surrounding low hilly area (200–250 m) that are both dissected by the NNW–SSE striking Topčiderska Reka and Zavojnička Reka valleys (Fig. 16). These valleys represent ...
... deposits. The Torlak Hill (horst) is composed of Cretaceous and Middle Miocene Badenian and Sarmatian sedi- ments. Our research has generally confirmed the view of the afore- mentioned authors, but new insights have emerged on the nature and characteristics of the Beli Potok trough. Namely, on the left ...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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‘Blue-’ and ‘Brown-speckled’ pottery from Qalhât, the Sultanate of Oman (13–16th centuries): Comparison with traditional Omani 19–20 century productions
Representative ‘Blue speckled’ (13–16th centuries) and ‘Brown speckled’ (13–21st century) wares recovered from the excavations in Qalhât or collected around Bahlâ city (Sultanate of Oman) were characterized by XRPD, SEM-EDS, Raman/optical microspectroscopy, and thermal expansion. Minerals present in the body (quartz, augite and albite as major phases, calcite, dolomite, rutile, anatase, phosphate, hematite and magnetite as minor phases) were identified by XRPD and/or Raman spectroscopy. SEM-EDXS microanalysis was performed on the glazes in order to compare their composition, especially ...Liliana Gianni, Hélène Renel, Aleksandar Kremenović, Philippe Colomban. "‘Blue-’ and ‘Brown-speckled’ pottery from Qalhât, the Sultanate of Oman (13–16th centuries): Comparison with traditional Omani 19–20 century productions" in Boletín de la Sociedad Española de Cerámica y Vidrio, Elsevier BV (2020). https://doi.org/10.1016/j.bsecv.2020.06.005