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128 items
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Development and evaluation of fracture gradient curve model: a case study of south-central Kazakhstan
An accurate fracture gradient value is one of the most important issues in oil and gas well design and drilling. The value of a fracture gradient is a critical parameter for determining the drilling mud weight and selecting the proper depths for setting the casing in the planning process of drilling operations. This paper proposed the new curve model of fracture gradient for the south-central Kazakhstan (central Asia) region based on the analysis of leak-off test and format integrity ...Branimir Stanisavljevic, Vesna Karovic Maricic, Irena Isakov. "Development and evaluation of fracture gradient curve model: a case study of south-central Kazakhstan" in International Journal of Oil, Gas and Coal Technology, Inderscience Publishers (2022). https://doi.org/10.1504/IJOGCT.2023.128042
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Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector
To strengthen the security of supply of the Serbian gas sector, it is necessary to analyze the impact of planned strategic measures. The analysis involves the identification of the most influential threats to the security of natural gas supply and prioritization of the strategic measures for overcoming the consequences of threats. The proposed methodology is based on Fuzzy Analytic Hierarchy Process. The obtained weights for the identified threats and strategic measures are formed according to experts' judgments. The results ...Sigurnost snabdevanja, Donošenje odluka, Snabdevanje prirodnim gasom, Fazi AHP, Energetski indikatoriBoban Pavlović, Dejan Ivezić, Marija Živković. "Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector" in Energy Policy, Elsevier BV (2020). https://doi.org/10.1016/j.enpol.2020.111936
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Compaction of Municipal Solid Waste
Jovana Janković Pantic, Dragoslav Rakić, Tina Đurić, Irena Basarić Ikodinović, Snežana Bogdanović (2022)Regardless of the numerous activities undertaken to reduce municipal solid waste, its annual volumes continue to grow. In Serbia, the most common and the only one form of waste disposal is at municipal landfills with daily compaction and soil covering. Municipal waste compacting is one of the basic components of the disposal process. Well compacted waste takes up less volume and allows much safer storage. In order to better predict the behavior of municipal waste at landfills, it is ...Jovana Janković Pantic, Dragoslav Rakić, Tina Đurić, Irena Basarić Ikodinović, Snežana Bogdanović. "Compaction of Municipal Solid Waste" in ICEG 2022: International Conference on Environmental Geotechnics, World Academy of Science, Engineering and Technology (2022)
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Application of Peleg model on mass transfer kinetics during osmotic dehydratation of pear cubes in sucrose solution
Vesna Pavelkić, Tanja Brdarić, Marija Petrović, Gavrilo Šekularac, Milica Košević, Lato Pezo, Marija Ilić (2015)The applicability of Peleg model was investigated for predicting mass transfer kinetics during the osmotic dehydration (OD) process of pears, at different concentrations (40, 60 and 70%, w/w) and temperatures (20, 35 and 50 °C) of sucrose solution. Increase in sucrose solution concentration resulted in higher water loss (WL) and solid gain (SG) values through the osmotic treatment period. After 360 min of osmotic treatment of pears, WL ranged from 23.71 to 31.68% at 20 °C, from 24.80 to ...Vesna Pavelkić, Tanja Brdarić, Marija Petrović, Gavrilo Šekularac, Milica Košević, Lato Pezo, Marija Ilić. "Application of Peleg model on mass transfer kinetics during osmotic dehydratation of pear cubes in sucrose solution" in Chemical Industry and Chemical Engineering Quarterly (2015). https://doi.org/10.2298/CICEQ141014004P
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Geotechnical effects of municipal solid waste destruction with different compaction methods
Jovana M Janković Pantić, Dragoslav R Rakić, Irena G Basarić Ikodinović, Tina D Đurić, Gordana Hadži-Niković (2022)Disposal of waste in municipal solid waste landfills is the only way of waste disposal in Serbia, with daily compaction and covering with soil material. Due to less space for the construction of new landfills, it is necessary to use their maximum capacity. Well-compacted municipal solid waste takes up less volume and enables safer storage, so it is useful to previously determine the compaction parameters in the laboratory: maximum dry unit weight (γdmax) and optimal water content (wopt). In ...Jovana M Janković Pantić, Dragoslav R Rakić, Irena G Basarić Ikodinović, Tina D Đurić, Gordana Hadži-Niković. "Geotechnical effects of municipal solid waste destruction with different compaction methods" in Доклади на Българската академия на науките Comptes rendus de l’Acad´emie bulgare des Sciences (2022). https://doi.org/10.7546/CRABS.2022.01.13
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Projected changes in air temperature, precipitation and aridity in Serbia in the 21st century
Boško Milovanović, Sebastian Schubert, Milan Radovanović, Vesna Ristić Vakanjac, Christoph Schneider (2021)In this study, the projected changes of the average monthly and annual air temperatures, precipitation amounts and De Martonne aridity index in Serbia in the 21st century are examined. For that purpose, the spatial distribution of air temperature and precipitation amount is statistically modelled using data of 64 climatologic stations and 421 precipitation stations for the period 1976–2005 using multiple linear regression. The De Martonne aridity index is calculated from the spatially distributed data. In order to obtain regional ...Boško Milovanović, Sebastian Schubert, Milan Radovanović, Vesna Ristić Vakanjac, Christoph Schneider. "Projected changes in air temperature, precipitation and aridity in Serbia in the 21st century" in International Journal of Climatology (2021). https://doi.org/10.1002/joc.7348
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Effectiveness Analysis of Different Bucket-wheel Excavators
Coal production in open-pit lignite mines in the Republic of Serbia is performed with continuous work systems. In addition to coal production, the same systems are used for the exploitation of large quantities of overburden. According to the reliability concept, continuous systems are in linear connection. If the failure occurs in one part of the system, that will produce a downtime of the entire system. The initial and most important factor of continuous systems is the bucket-wheel excavator. It ...Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić. "Effectiveness Analysis of Different Bucket-wheel Excavators" in 8th International Conference Mining and Environmental Protection, Sokobanja, 22-25 September 2021, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2021)
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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 ...... documents are retrieved and ranked upon a user query on basis of this index, using an approximate matching model, such as the vector space model, based on weight coefficients of terms, or the probabilistic model, based on relevance feedback [22]. When language processing methods and techniques are used for ...
... skupština opštine ‘municipality council’) and symbols of chemical elements (e.g. Ca for calcium). For each field searched within a specific facet, a weight factor is assigned. For example, when the facet ‘location’ is used in a query, the weights of corre- sponding metadata fields are: Municipality 8, ...
... the 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 ...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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An Approach to Efficient Processing of Multi-Word Units
Efficient processing of Multi-Word Units in the course of development of morphological MWU dictionaries is not easy to achieve, especially when languages with complex morphological structures are concerned, such as Serbian. Manual development of this type of dictionaries is a tedious and extremely slow process. To alleviate this problem we turned to our multipurpose software tool, dubbed LeXimir, in the production of lemmas for e-dictionaries of multi-word units. In addition to that, we developed a procedure aimed at making ...Cvetana Krstev, Ivan Obradović, Ranka Stanković, Duško Vitas. "An Approach to Efficient Processing of Multi-Word Units" in Computational Linguistics - Applications, Studies in Computational Intelligence 458 no. 458, Berlin Heidelberg : Springer-Verlag (2013): 109-129. https://doi.org/10.1007/978-3-642-34399-5_6
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Modern self-propelled surface drill rigs for drilling small diameter holes in mining and construction operations
Milanka Negovanović, Lazar Kričak (2021)Приликом одређених рударских или грађевинских радова потребно је извршити минирање применом бушотина малог пречника. Раније, бушење бушотина малих пречника се изводило углавном ручним бушилицама или лаким лафетним бушилицама нa одређеним нoсачима. Проблеми у овим случајевима били су капацитет бушења, бушење већих дужина бушотина и посебно безбедност оператера на неприступачним теренима, где је његово присуство било неопходно. Данас постоје модерне самоходне бушилице за бушење минских бушотина малог пречника, које су у потпуности даљински управљане. Радио даљинска контрола омогућава да се ...Бушилице,бушотине малог пречника, бушење, минирање,изградња,минирање негабарита, радио даљинска контролаMilanka Negovanović, Lazar Kričak . "Modern self-propelled surface drill rigs for drilling small diameter holes in mining and construction operations" in 8th International Conference Mining And Environmental Protection, Sokobanja, 22 – 25th September 2021 SERBIA,, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2021)
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Značaj izvodjenja Proktorovog opita na komunalnom otpadu
Komunalni otpad predstavlja jedan od ključnih problema današnjice. U Srbiji je najčešći vid odlaganja otpada na komunalne deponije i zbog toga je bitno ispravno i sigurno ga skladištiti. Zbijanje komunalnog otpada predstavlja jednu od osnovnih komponenti procesa odlaganja. Kako bi se što bolje predvidelo ponašanje komunalnog otpada neophodno je pre zbijanja na terenu laboratorijski odrediti maksimalnu suvu zapreminsku težinu i optimalnu vlažnost. U dosadašnjoj praksi u svetu za to se koristi standardizovan Proktorov opit. U radu će biti prikazani ...... components of the disposal process. In order to better predict the behaviour of municipal waste, it is necessary to determine the maximum dry unit weight and optimal moisture content before compaction in the terrain, for which Standard Proctor test has been used in the world current practice. This ...Jovana Janković, Dragoslav Rakić, Tina Đurić, Irena Basarić Ikodinović, Laslo Čaki. "Značaj izvodjenja Proktorovog opita na komunalnom otpadu" in Zbornik radova osmog naučno-stručnog međunarodnog savetovanja - Geotehnički aspekti građevinarstva, Savez građevinskih inženjera Srbije (2019)
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Projected changes in air temperature, precipitation and aridity in Serbia in the 21st century
Boško Milovanović, Sebastian Schubert, Milan Radovanović, Vesna Ristić Vakanjac, Christoph Schneider (2021)У овој студији се испитују пројектоване промене средњих месечних и годишњих температура ваздуха, количине падавина и Де Мартоновог индекса аридности у Србији у 21. веку. У ту сврху статистички је моделована просторна дистрибуција температуре ваздуха и количине падавина на основу података 64 климатолошке станице и 421 падавинске станице за период 1976–2005 применом вишеструке линеарне регресије. Де Мартонов индекс аридности се израчунава из просторно распоређених података. Да бисмо добили регионалне просеке и варијабилност, Србију делимо на три поддомена: западну зону ...Boško Milovanović, Sebastian Schubert, Milan Radovanović, Vesna Ristić Vakanjac, Christoph Schneider. "Projected changes in air temperature, precipitation and aridity in Serbia in the 21st century" in International Journal of Climatology, Wiley (2021). https://doi.org/10.1002/joc.7348
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New insights into tectonic relations between the Eastern Vardar Ophiolitic and Serbo-Macedonian units: Inferences from a microtectonic study in central Serbia
Maja Maleš, Nikola Ranđelović, Nemanja Krstekanić, Bojan Kostić, Nikolina Ćirić, Uroš Stojadinović (2023)Источно-вардарски офиолити, Српско-македонска јединица, микротектонска анализа, каснојурска обдукција, пост-обдукционе деформацијеMaja Maleš, Nikola Ranđelović, Nemanja Krstekanić, Bojan Kostić, Nikolina Ćirić, Uroš Stojadinović. "New insights into tectonic relations between the Eastern Vardar Ophiolitic and Serbo-Macedonian units: Inferences from a microtectonic study in central Serbia" in Geološki anali Balkanskoga poluostrva (2023). https://doi.org/10.2298/GABP230130002M
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Geotehnički efekti razaranja komunalnog otpada različitim postupcima zbijanja
Jovana M. Janković Pantić (2022)Odlaganje otpada na komunalne deponije predstavlja osnovni način zbrinjavanja otpada u Srbiji. Kako bi se prostor za deponovanje materijala racionalno koristio potrebno ga je svakodnevno zbijati sa unapred definisanom količinom vode koja se dodaje. Dobro zbijeni komunalni otpad zauzima manju zapreminu i omogućuje sigurnije skladištenje, pa je korisno prethodno laboratorijski odrediti parametre zbijanja: maksimalnu suvu zapreminsku težinu (dmax) i optimalnu vlažnost (wopt). U Srbiji do sada nisu određivani parametri zbijanja, dok je u svetu primenjivana standardna metoda (Proktorov opit) ...Jovana M. Janković Pantić. Geotehnički efekti razaranja komunalnog otpada različitim postupcima zbijanja, Beograd : [J. Janković Pantić], 2022
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Definition of criteria and alternatives for choosing the optimal mining method deposits when applying multi: Criteria optimization, Belgrade, June 2024
Sanja Bajić, Dragoljub Bajić, Branko Gluščević, Radmila Gaćina, Josip Išek. "Definition of criteria and alternatives for choosing the optimal mining method deposits when applying multi: Criteria optimization, Belgrade, June 2024" in Podzemni radovi, Beograd, jun 2024, Centre for Evaluation in Education and Science (CEON/CEES) (2024). https://doi.org/10.5937/podrad2444071B
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Overwiew of In-Pit Crushing & Conveying Technology in Open Pit Mines
The conditions under which contemporary surface mining operations is carried out obviously becoming increasingly complex. In such complex conditions, the optimization of haulage systems as the technological phase with the largest share in the total operating costs, is very important from the aspect of achieving profitability of the mining project. In a large number of cases, the application of traditional haulage systems with trucks (as the most dominant type of haulage in open pit mines) does not lead to ...Ali Nasirinezhad, Dejan Stevanović, Dragan Ignjatović, Petar Marković. "Overwiew of In-Pit Crushing & Conveying Technology in Open Pit Mines" in 8th International Conference MIining And Environmental Protection, Sokobanja, 22-25 September 2021, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2021)
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Replica of the “Great Triangle Gold Nugget” Belonging to Belgrade University Collection, Gilded or Not?
... mining engineer M. Melnikoff, conservator of the Mining Institute Museum in St. Petersburg, contains details of its location of finding, the weight of the natural nugget (Archive of the Collection of Rocks and Minerals), but with no information of the number of the replica made, and the type ...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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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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Surface functional groups and degree of carbonization of selected chars from different processes and feedstock
Marija Ilić, Franz-Hubert Haegel, Aleksandar Lolić, Zoran Nedić, Tomislav Tosti, Ivana Sredović Ignjatović, Andreas Linden, Nicolai D. Jablonowski, Heinrich Hartmann (2022)The knowledge ofthe structural and chemical properties of biochars is decisive for their application as technical products. For this reason, methods for the characterization of biochars that are generally applicable and allow quality control are highly desired. Several methods that have shown potential in other studies were used to investigate two activated carbons and seven biochars from different processes and feedstock. The chars were chosen to cover a wide range of chemical composition and structural properties as a hardness ...Biougalj, različiti procesi dobijanja, različite sirovine, površinski aktivne grupe, x-ray, FT-IR,XPS... November 17, 2022 8/38 PLOS ONE Surface functional groups and degree of carbonization of selected chars "Table 2. Composition of chars in weight per weight %. Chars Xo/ % Xa/ % XN/ % No/ % Xs % ACI 85.4+0.38 0.96+0.03 0.63+0.05 6.9+0.1 0.719+0.01 AC2 77.1+0.53 3.51+0.04 <04 17.8+0.8 <0.01 ...
... and H were performed on a Vario EL cube (Elementar Analysensysteme GmbH, Langenselbold, Germany). All chars were dried at 106 "C until constant weight. Oxygen was determined with a LECO TCH600 (LECO, St. Joseph, MI, USA). The ash content was determined in a muffle furnace at 815 + 15 "C. Three samples ...
... leachates. A sample of 0.500 g of HCI-treated char was shaken with 25 ml of0.05 mol1! NaOH for 24 h to extract organic components of low molecular weight. The solid was separated from the solution by filtration using 0.45 um nitrocellulose fil- ters. The absorbance at 250 nm (A250) was measured as ...Marija Ilić, Franz-Hubert Haegel, Aleksandar Lolić, Zoran Nedić, Tomislav Tosti, Ivana Sredović Ignjatović, Andreas Linden, Nicolai D. Jablonowski, Heinrich Hartmann. "Surface functional groups and degree of carbonization of selected chars from different processes and feedstock" in PLOS ONE (2022). https://doi.org/10.1371/journal.pone.0277365
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Knowledge and Rule-Based Diacritic Restoration in Serbian
In this paper we present a procedure for the restoration of diacritics in Serbian texts written using the degraded Latin alphabet. The procedure relies on the comprehensive lexical resources for Serbian: the morphological electronic dictionaries, the Corpus of Contemporary Serbian and local grammars. Dictionaries are used to identify possible candidates for the restoration, while the dataobtainedfromSrpKorandlocalgrammarsassistsinmakingadecisionbetween several candidates in cases of ambiguity. The evaluation results reveal that,dependingonthetext,accuracyrangesfrom95.03%to99.36%,whilethe precision (average 98.93%) is always higher than the recall (average 94.94%).... ”population aging” was explicitly mentioned only once in the text, and it could obtain a too low frequency-based weight, but with the support of the main topic node ”demographic situation”, its weight is considerably higher; • Calculation of category weights in dependence of concepts included into the rules ...
... 271,297 3www.labinform.ru/pub/ruthes/index.htm Proceedings of CLIB 2018 95 4. Specific Features of RuThes Structure The main unit of RuThes is a concept as a unit of thought regardless of words expressing it. A concept has a unique, unambiguous name. Concept names are similar to descriptors in ...
... Forming the conceptual index of the document. Conceptual index of a document consist of con- cepts found in the document and their assigned weights. The weight of a concept accounts for the 4(https://www.rbc.ru/economics/17/11/2017/5a0eb1d39a79470f724250b4 Proceedings of CLIB 2018 99 significance of ...Cvetana Krstev, Ranka Stanković, Duško Vitas. "Knowledge and Rule-Based Diacritic Restoration in Serbian" in Proceedings of the Third International Conference Computational Linguistics in Bulgaria (CLIB 2018), May 27-29, 2018, Sofia, Bulgaria, Sofia : The Institute for Bulgarian Language Prof. Lyubomir Andreychin, Bulgarian Academy of Sciences (2018): 41-51