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Упит dcterms_subject_txt:Materials Chemistry,Inorganic Chemistry,Physical and Theoretical Chemistry

2353 items

  • Simple 2D gravity–density inversion for the modeling of the basin basement: example from the Banat area, Serbia

    Ivana Vasiljević, Snežana Ignjatović, Dragana Đurić (2019)
    We have developed a technique to calculate lateral density distribution of the sedimentary basin basement by combining linear gravity–density inversion and 2D forward modeling. The procedure requires gravity anomaly data, depth-to-basement data and density data for the sediments (density–depth distribution). Gravity efect of density variations in the basement was extracted from the total gravity anomaly by removing the joint efect of the sediments with vertical density variations and homogeneous basement of average density contrast (calculated by 2D modeling). Gravity ...
    funkcije raspodele gustine, lateralna raspodela gustine, karta gustine podloge

  • Development of an integrated model for open-pit-mine discontinuous haulage system optimization

    Miodrag Čelebić, Dragoljub Bajić, Sanja Bajić, Mirjana Banković, Duško Torbica, Aleksej Milošević , Dejan Stevanović (2024)
    equipment selection, mine mechanization, expert judgment, linguistic variables, MCDM, FAHP

  • Numerical Models of Debris Flows with Entrainment Analysis-Case Studies from the Republic of Serbia

    Jelka Krušić , Biljana Abolmasov, Miloš Marjanović (2021)
    The results of material entrainment analysis in RAMMS debris flow software, as well as numerical models of final flow heights for two case studies from the Republic of Serbia are presented. Both of debris flow cases started with initial sliding of huge volume block, prolonging to behave as flowing process. Results of the analysis showed that entrainment material affects final results of transportation model, runout distance, deposition area and volume of debris flow. In both cases entrainment volume is very ...
    tecišta, zadržavanje nanosa, RAMMS, validacija

  • Overwiew of In-Pit Crushing & Conveying Technology in Open Pit Mines

    Ali Nasirinezhad, Dejan Stevanović, Dragan Ignjatović, Petar Marković (2021)
    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 ...
    In Pit Crushing and Conveying, IPCC, open pit mining, haulage, optimization, costs saving

  • Understanding partitioning of deformation in highly arcuate orogenic systems: Inferences from the evolution of the Serbian Carpathians

    Nemanja Krstekanić, Liviu Matenco, Marinko Toljić, Oleg Mandić, Uroš Stojadinović, Ernst Willingshofer (2020)
    orogeneza, oroklini, višesmerna ekstenzija, transkurentna kretanja, Srpski Karpati
    ... calculate and optimise reduced paleostress tensors (Figs. A.1, A.2 and Table A.1 of the Supplementary Appendix) by following a standard inversion approach with confidence criterion (e.g., Angelier, 1994; Angelier and Goguel, 1979; Angelier and Mechler, 1977; Delvaux and Sperner, 2003 and references ...
    ... (Lesić et al. (2019). These rotations and translations were associated with Eocene–early Miocene orogen-parallel extension and ~ 100 km of dextral strike-slip offset along the curved Cerna–Jiu and Timok faults system in the South and Serbian Carpathians, and a gradual transtensive opening of basins ...
    ... Global and Planetary Change 195 (2020) 103361 4 Fig. 2. Tectonic map of the Serbian Carpathians and adjacent areas of the South Carpathians and Balkanides showing the regional fault kinematics (compiled and modified after Basic geological map of former Yugoslavia, scale 1:100.000 and Maţenco, ...

  • Heavy metals in lignite and soil of Kostolac-Kovin coal basin, eastern Serbia - comparative analysis with selected cities in Serbia, region, Europe and world

    Bogoljub Vučković, Bojan Dimitrijević (2023)
    The Kostolac-Kovin coal basin with an area of 320 km2, with 5 separate layers of coal and with a total of about 5.7 Bt of geological resources and reserves represents an exceptional potential for coal production in Serbia. The coal resources listed in this way are not fully exploitable, but they represent potential for consideration. In this paper, we deal with the geochemical characteristics of coal seams and perform a comparative analysis of coal affectation on the environment. With ...
    lignite, heavy metals, concentrations
    ... pits of Stari Kostolac and Ćirikovac, after that in the surface mines of Klenovnik and Cirikovac, picture 2) and are not being excavated now; 177 2. Now in the excavation phase are some parts of 1, II and III layers (I and II layers in Kovin by underwater exploitation; II and III layers in the Drmno ...
    ... seams and perform a comparative analysis of coal af}ectation on the environment. P/ith 155 analyzes of HM from coal, 45 from ash, 165 from gravel and 30 from soil, we perform analysis of horizontal and vertical distribution of HM and comparative analysis. B/hat interests us as authors and you as ...
    ... the Velika Morava and Mlava rivers, which flow into the Danube in that area (figure 1 and 2). Itis divided into two parts by the Danube - to the south is the Kostolac Basin, and to the north ofthe Danube is the Kovin Basin (Figure 2). Geological explorations began in 1941 and continues to this day ...

  • Application of the VIKOR Method for Selecting the Purpose of Recultivated Terrain after the End of Coal Mining

    Radmila Gaćina, Sanja Bajić, Bojan Dimitrijević, Tomislav Šubaranović, Čedomir Beljić, Dragoljub Bajić (2024)
    reclamation, coal, sustainable development, multi-criteria decision making, VIKOR method

  • Two approaches to compilation of bilingual multi-word terminology lists from lexical resources

    Branislava Šandrih, Cvetana Krstev, Ranka Stanković (2020)
    In this paper, we present two approaches and the implemented system for bilingual terminology extraction that rely on an aligned bilingual domain corpus, a terminology extractor for a target language, and a tool for chunk alignment. The two approaches differ in the way terminology for the source language is obtained: the first relies on an existing domain terminology lexicon, while the second one uses a term extraction tool. For both approaches, four experiments were performed with two parameters being ...
    Linguistics and Language,Software,Artificial Intelligence,Language and Linguistics

  • Linear-motor plunger pump increases lifting efficiency

    Bojan Martinović, Dušan Đekić, Dušan Danilović, Pavel Isaev (2022)
    plunger, linear, motor, pumps

  • Long-term planning methodology for improving wood biomass utilization

    Vladimir Vukašinović, Dušan Gordić, Marija Živković, Davor Koncalović, Dubravka Živković (2019)
    The insufficiently developed forest management system is often followed by undeveloped forest resources supply chain and insufficient institutional support. These cause inefficient usage of fuel-wood as well as huge amounts of unused forest residues. In order to achieve optimal and long-term sustainable utilisation of biomass, an original methodology based on the interaction of mathematical optimization and backcasting approach has been developed. Mathematical optimization is used for both generation and consideration of techno-economic parameters of the forest biomass supply chain. ...
    Long-term planning methodology, Forest biomass, MINLP, Backcasting

  • A Lexical Approach to Acronyms and their Definitions

    Cvetana Krstev, Duško Vitas, Ranka Stanković (2015)
    In this paper we present a comprehensive approach to acronyms for Natural-Language Processing (NLP) of Serbian texts. The proposed procedure includes extraction of acronyms and their definitions that are usual Multi-Word Units (MWUs), shallow parsing of MWUs that enables MWU lemmatization and production of entries in morphological electronic dictionaries, both for MWU and acronyms, that are provided with grammatical, syntactic, semantic and domain information. This approach enables representation that reflects complex relations between acronyms and their definitions.
    ... texts (57% daily, 8% weekly and 5% monthly newspapers) and 6% of monographs and textbooks (Krstev and Vitas, 2005), which are types of texts that tend to use acronyms and pro- vide definitions. Besides that we used two more samples of newspaper texts (having 600 thousand and 1.200 thousand simple word ...
    ... Electronic Communication and Postal Services’. Moreover, in many cases a relation between an entity and its name and acronym is not one-to-one. The name can change in time and some shortened variants can be in use, translated names can exhibit serious variations in used lexica and syntactic forms, original ...
    ... of Education and Science under grants 47003 and 178003. 6. References Jacobs, K., A. Itai, and S. Wintner, 2014. Acronym Dic- tionary Construction and Disambiguation (abstract). 3rd Parseme General Meeting – Poster Session. Krstev, C., R. Stanković, I. Obradović, D. Vitas, and M. Utvić, 2010 ...

  • Multihazard Exposure Assessment on the Valjevo City Road Network

    Miloš Marjanović, Biljana Abolmasov, Svetozar Milenković, Uroš Đurić, Jelka Krušić, Mileva Samardžić Petrović (2019)
    Prirodni hazardi, izloženost, klizišta, poplave, bujice, GIS, R

  • Terminology Acquisition and Description Using Lexical Resources and Local Grammars

    Cvetana Krstev, Ranka Stanković, Ivan Obradović, Biljana Lazić (2015)
    Acquisition of new terminology from specific domains and its adequate description within terminological dictionaries is a complex task, especially for languages that are morphologically complex such as Serbian. In this paper we present an approach to solving this task semi-automatically on basis of lexical resources and local grammars developed for Serbian. Special attention is given to automatic inflectional class prediction for simple adjectives and nouns and the use of syntactic graphs for extraction of Multi-Word Unit (MWU) candidates for ...
    ... optics, medicine, physics and mathematics, psy- chology) showed that 97% of multi-words in these sources consist of nouns and adjectives only, and more than 99% consist only of nouns, adjectives, and a preposition. (Justeson & Katz, 1995) Identifying the adjectives and the preposi- tional phrase ...
    ... Acquisition and Description Using Lexical Resources and Local Grammars Cvetana Krstev, Ranka Stanković, Ivan Obradović, Biljana Lazić Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Terminology Acquisition and Description Using Lexical Resources and Local Grammars ...
    ... dictionary of prefixes and the remainder of the lemma is a word in DELAS, then the lemma is the inflectional class of the corresponding DELAS word is assigned to the lemma. 4. For thresholds 80 and less steps 1 and 2 only are repeated. From a sample of domain texts and dictionar- ies we manually ...

  • History of meteorite donations to the Collection of Minerals and Rocks of the University of Belgrade, Faculty of Mining and Geology (Serbia)

    Alena Zdravković, Maja Milošević, Kristina Šarić, Ivana Jelić, Ana Černok (2021)
    ... Čačak in 1919, and Dimitrovgrad in 1947), contributed to further developments of meteorite collections and increased the potential for sample exchanges with foreign museums. Prof. Josif Pančić was a very active and respected scientist across Europe, and with his collaborations and private efforts ...
    ... Mining and Geology (UBFMG) contains 52 meteorites organized in two collections: 36 samples are stored in the Collection of Minerals and Rocks and 16 pieces are kept in the Paleontological Collection. In this paper we describe the collection of meteorites at the Collection of Minerals and Rocks, ...
    ... 202 g and P81 Fe-meteorite 48.8 g), and one obviously non-iron meteorite sample that is still unclassified (11.5 cm long). The significance of preserved meteorite specimens in old university collections such as the Collection of Minerals and Rocks at UBFMG is huge both from historical and scientific ...

  • Projecting short to medium-term effects of carbon emissions trading on Serbia's GDP

    Boban Pavlović, Nikola Trtica (2024)
    This paper presents an approach to assess the short to medium-term effects of the Emissions Trading System (ETS), an economic and climate policy instrument aimed at reducing greenhouse gas emissions, on GDP from the expenditure side. The analysis focuses on Serbia’s electricity sector, which relies heavily on lignite-based pro duction dominated by state-owned enterprises. The obtained projections suggest that in the short term, the introduction of an ETS may lead to slower GDP growth compared to official forecasts. However, ...
    ETS, BDP - rashodni pristup, cene električne energije
    ... background information on the Serbian economy and energy system, methodology, and the design of scenarios. The third section presents the results and discusses the results obtained. Conclusions are summarized in the final section. 2. Materials and methods Understanding the dynamics of key economic ...
    ... to carbon pricing are changes in its ability to produce goods and services, driven by ad- vancements in technology, innovations (Dong and Xiao, 2024) or changes in the availability of resources like machinery, workers, and materials (\WWilliams, 2015). However, during short-term economic fluctuations ...
    ... an ETS and other carbon pricing pol- icies under different conditions, scenarios, and policy frameworks. These studies examine industry competitiveness (Joltreau and Som- merfeld, 2019), employment effects (Chen and Wang, 2023), ETS price dynamics (Li et al.., 2019), trade patterns and spillover ...

  • Approach to operational mine planning: Case study Tamnava West

    Dejan Stevanović, Mirjana Banković, Milica Pešić Georgiadis, Ranka Stanković (2014)
    ... many analysis of the technical and economic parameters and detailed planning of all possible scenarios of production. Due to availability of the coal resources and their price stability, coal is and will retain its important role in power generation in Europe and worldwide 1. In Serbia, coal ...
    ... integrated geology and mine planning solutions. It is comprehensive tool specialized for coal and other stratified deposits, such as phosphate, zinc, bauxite, iron ore, and platinum. Minex covers almost every part of geological modeling and mine planning process. It provides a fast and powerful set ...
    ... within Minex called the "Splitting" and "Father and Son" concept was applied and the gridding mesh size was set at 25 m x 25 m to cover all boreholes. An exceptionally large scan distance of 35,000m was selected for seam General Purpose interpolation, and for assay data Inverse Distance, power ...

  • Design of a sucker rod pumping system

    Ana Ponoćko (2024)
    For a long time in the history of oil production, sucker rod pumps have been the first and in many cases the only choice when it comes to mechanical extraction methods. Proper selection of each individual element of the system enables optimization, which entails benefits in the form of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The ...
    sucker rod pump, fluid production, mechanical extraction methods,, Prosper, QROD, RODSTAR
    ... valve. The dimensions and configuration of the internal diameter of the valve body should ensure adequate clearance and fluid flow with minimal pressure drop. The API specification pertains only to the dimensions and not to the materials of the component. The ball and seating nipple constitute ...
    ... equipment and reducing maintenance time. The option to choose different materials for the moving and stationary parts of the pump, along with a variety of design solutions, makes this type of pump adaptable to different exploitation conditions. Compared to tubing pumps, the piston and cylinder ...
    ... of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The second part involves an analysis and calculations using the "RODSTAR", "QRod" and "Prosper" software, which ...

  • SASA Dictionary as the Gold Standard for Good Dictionary Examples for Serbian

    Ranka Stanković, Branislava Šandrih, Rada Stijović, Cvetana Krstev, Duško Vitas, Aleksandra Marković (2019)
    У овом раду представљамо модел за избор добрих примера за речник српског језика и развој иницијалних компоненти модела. Метода која се користи заснива се на детаљној анализи различитих лексичких и синтактичких карактеристика у корпусу састављених од примера из пет дигитализованих свезака речника САНУ. Почетни скуп функција био је инспирисан сличним приступом и за друге језике. Дистрибуција карактеристика примера из овог корпуса упоређује се са карактеристиком дистрибуције узорака реченица ексцерпираних из корпуса који садрже различите текстове. Анализа је показала да ...
    Српски, добри примери из речника, аутоматизација израде речника, издвајање својстава, Машинско учење
    ... various lexical and syntactic features of the gold standard examples, classified them and compared the results with the control corpus (both gold and control corpus are presented in Section 4). The initial set of features was inspired by Kilgarriff et al. (2008) and Kosem (2017), and guided by rec ...
    ... ) in the sentence; and since examples should help the understanding of the definition, they must be easy to understand – which means that their syntactic structure should be simple and their lexis not too difficult and uncommon. Informativeness, typicality with naturalness, and intelligibility are ...
    ... while 5% had an insertion but were not shortened and 2% had both insertions and shortenings. The number of editorial examples was relatively small, and we have not used these in our test set. 2.3.5 What should a good example contain? As Atkins and Rundell (2008) point out, there is plenty of evidence ...

  • Extensive vibrations of the belt conveyer drive electromotor of a bucket wheel excavator as a result of intesified wear-and-tear of its mount support

    Vesna Damnjanović, Predrag Jovančić, Snežana Aleksandrović (2017)

  • The state and perspective of the natural gas sector in Serbia

    Dejan Ivezić, Marija Živković, Dušan Danilović, Aleksandar Madžarević, Miloš Tanasijević (2016)
    The strategy of long-term energy development of Serbia identifies an increase of share of natural gas in final energy consumption as one of the main aims. Serbia has signed a strategic agreement with the Russian Federation on cooperation in the oil and gas sector, within which the project South Stream pipeline is planned to be realized. In addition, the Republic of Serbia has signed the Treaty that establishes the Energy Community and accepted the obligation to implement the Energy ...
    Consumption, natural gas, scenarios of development