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Упит dcterms_subject_txt:Economics and Econometrics

2341 items

  • A Model for Determining the Dependability of Continuous Subsystems in Coal Mines Using the Fuzzy Logic Approach

    Nikola Stanić, Miljan Gomilanović, Petar Marković, Daniel Krzanović, Aleksandar Doderović, Saša Stepanović (2024)
    This study presents a unique model for assessing the dependability of continuous parts of combined systems in open-pit mining through the application of fuzzy logic. Continuous sub-systems as part of the combined system of coal exploitation in surface mines have the basic function of ensuring safe operation, high capacity with high reliability, and low costs. These subsystems are usually part of the thermal power plant’s coal supply system and ensure stable fuel supply. The model integrates various independent partial ...
    fuzzy logic, max-min composition, continuous part of combined system (CCS), open pit, mining, dependability

  • Old or New, We Repair, Adjust and Alter (Texts)

    Cvetana Krstev, Ranka Stanković (2020)
    U ovom radu predstavljamo kako se e-rečnici i kaskade transduktora konačnih stanja implementirani u alatu Unitex mogu koristiti za rešavanje tri problema transformacije teksta: ispravljanje tekstova nakon OCR-a, vraćanje dijakritičkih znakova i prebacivanje između različitih jezičkih varijanti.
    ispravka teksta, OCR greške, restauracija dijakritika , jezičke varijante, elektronski rečnik, transduktori konačnih stanja
    ... confused, for instance letters ‘п’, ‘и’, ‘н’, letters ‘с’ and ‘е’, letters ‘с’ and ‘о’ (but not ‘е’ and ‘о’); – A group of letters can be confused for one letter or another group of letters, e.g. two letters ‘га’ and one letter ‘ш’; two letters ‘шп’ and two letters ‘иш’; – Letters can be confused for digits ...
    ... Latin alphabet that can be accommo- dated by ASCII character set, and affects five letters: š, d, č, ć and ž. As a result, some letters or letter groups become ambiguous: – c – can stand for č and ć (and c); – z – can stand for ž (and z ); 5 The example text is from the novel by Lazar Komarčić ...
    ... paper – s – can stand for š (and s); – dj – can stand for d (and dj ); – dz – can stand for dž (and dz ). When compared with the problem of OCR errors, it can be observed that the repertoire of these “errors”6 as well as their possible corrections is limited and is known in advance. Namely, candidates ...

  • Synergy between the mineral deposit exploration and geothermal resources assessment on the example of "Valjevo" boron and lithium deposit in Serbia

    Nebojša Atanacković, Vladimir Živanović, Ana Vranješ, Sava Magazinović, Marinko Toljić, Ana Arifović, Branislav Potić (2023)
    Exploration of mineral deposits involves a collection of vast data sets on geological characteristics of the area. These data can largely contribute to the assessment of the geothermal potential, which can lead to an increase in the share of geothermal resources in the energy mix of the extractive industry and the local community. On the example of the "Valjevo" B-Li deposit, data on structural settings and previous hydrogeological investigations were combined with the results of resource drilling and geophysical ...
    Geothermal assessment, Mineral deposit exploration, Geothermal potential, Serbia
    ... Mionica and surrounding settlements. Karst groundwater under artesian pressure and elevated temperatures (17–37 "C) are taped with wells drilled below the Miocene cover in the surrounding. settlements of Paštrić, Sanković and Petnica. 3. MATERIALS AND METHODS Considering the available data and the ...
    ... probertite, ulexite, sirlezite, massive borax and Li-bearing smectite and silinaite minerals, deposited in three main zones: Borate zone, Borax zone and Lithium-borate zone. The basin basement in the north part is dominated by lower Triassic clastic and Paleozoic metamorphic sediments, while to the ...
    ... deposit exploration and geothermal resources assessment on the example of "Valjevo" boron and lithium deposit in Serbia | Nebojša Atanacković, Vladimir Živanović, Ana Vranješ, Sava Magazinović, Marinko Toljić, Ana Arifović, Branislav Potić | Proceedings 9th International Conference mining and environmental ...

  • Mineralogical and physicochemical characterization of bentonite clay from Svrljig, Serbia

    Maja Milošević, Bojan Kostić (2022)
    ... spacing value of 15.11 Å at 5.86 (2θ) and less frequent minerals such as quartz, carbonates and feldspars. This mineralogy was confirmed by XRD for oriented, saturated and heated samples. DTA curve, in addi- tion to the typical peaks related to montmorillonite (≈ 140 °C and 600 °C), also contains two smaller ...
    ... 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. 451-03-68/2022-14/200126 ...
    ... Kliment Ohridski” Earth and Man National Museum Scienti�c and Technical Union of Mining, Geology and Metallurgy PLATINUM SPONSOR GOLD SPONSORS ORGANIZERS AND SPONSORS Lead partner Host Institution ...

  • Application of ERT in the study of debris-flow source area: Case study Selanac debris flow

    Dragana Đurić, Jelka Krušić, Biljana Abolmasov (2021)

  • Infotheca (Q25460443) in Wikidata

    Ranka Stanković, Lazar Davidović (2021)
    Vikipodaci su baza znanja Zadužbine Vikimedija koja predstavlja zajednički izvor različitih vrsta podataka koje koriste ne samo drugi Vikipedijini projekti, već sve više i brojne aplikacije semantičkog veba. U ovom radu ćemo prezentovati primer integracije Vikipodataka sa digitalnim bibliotekama i eksternim sistemima, kao i mogućnost ubrzanja pripreme i unosa podataka na primeru radova iz časopisa za digitalnu humanistiku Infoteka.
    semantički veb,otvoreni povezani podaci, vikpodaci,Infoteka, metapodaci časopisa
    ... Šandrih, and Kitanović 2019). For a number of years now, students at the Faculty of Mining and Geology have been undergoing training to enter data into and use the Wikidata11 database, while the In- telligent Systems doctoral course features the subjects Knowledge Represen- tation and Semantic Web ...
    ... the item’s corresponding title and description, so as to remove any ambiguity. An identifier of a data item (QID) can, in addition to being linked to a title and a description, have a number of aliases and statements (claims, expressions) representing its properties and values. A statement is an ordered ...
    ... RDF triples and it is a very important step. Here are some characteristic examples with comments: – Title (P1476), in English and Serbian (both scripts, Cyrillic and Latin, for the sake of search); – Main subject of the creative work (P921), key words, where the existing ones are linked and new ones are ...

  • Classification of Terms on a Positive-Negative Feelings Polarity Scale Based on Emoticons

    Mihailo Škorić (2017)
    The goal of this paper is to draw attention to the possibility of using emoticon-riddled text on the web in language-neutral sentiment analysis. It introduces several innovations in the existing framework of research and tests their effectiveness. It also presents a software tool especially made for that purpose, explains how it builds a database with sentimental value of terms and offers the user manual. Finally, it presents a software tool that tests the new database and gives some examples ...
    data mining, information extraction, emotions, text on the web
    ... will be searched for and the values that they stand for. Determiners and values can be set one by one, or this step can be skipped. In case this step is skipped, the software will automatically load the default determiners and their values (Table 1). All default determiners and their values listed in ...
    ... are replaced with hahaha and haha respectively. If this option is not checked, this step will be skipped and only determin- ers in its default form, which is listed on the advanced mining tab, will be found and processed. The mere extraction involves loading selected terms and their values from advanced ...
    ... will not be executed, and if the value of an expression is not between −1 and 1 the program will report an error and stop the execution. After each of the determiners is replaced with a node whose attribute is its value (Figure 6), XML document becomes well-formed again and is ready for further processing ...

  • The Potential of Biomarkers to Distinguish Lower and Middle Miocene Lignites from the Coal-Mining District of Lusatia

    I. Kojic, J. Kus, D. Zivotic, K. Stojanovic (2021)
    ... Cupressaceae and Phyllocladaceae, whereas cuparene and dehydroicetexane are specific for Cupressaceae (Nytoft et al., 2019). Slight input of aquatic macrophytes and ferns is also evident. The degrees of aromatization of diterpenoids and non-hopanoid pentacyclic triterpenoids (Stojanović and Životić ...
    ... greater contribution of angiosperms. The contents of C27 and C29 n-alkanes in relation to C31 and C33 homologues imply similar impact of forested and reed-mire vegetation. The presence of tricyclic (abietane, pimarane, isopimarane) and tetracyclic (phyllocladane, bayerane, kaurane) diterpenoids ...
    ... DISTINGUISH LOWER AND MIDDLE MIOCENE LIGNITES FROM THE COAL-MINING DISTRICT OF LUSATIA I. Kojić1, J. Kus2, D. Životić1, K. Stojanović1 1University of Belgrade, Serbia 2Federal Institute for Geosciences and Natural Resources, Germany The organic geochemical study of Lower and Middle Miocene ...

  • Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans

    Zoran Stevanović, Aleksandra Maran Stevanović, Želimir Pekaš, Romeo Eftimi, Veljko Marinović (2021)
    Karst terrains cover some 30% of the Western Balkans, where rich karst aquifers represent the main source of potable water supply and ensure the development of local economies and tourism. In this “classical karst” region, there are also numerous sites or areas under different forms of protection—from those that are included in the UNESCO World Heritage list to natural monuments and landscapes that are protected by national legislation. In and around them are specific representatives of flora and fauna ...
    Karst, Zaštićena područja, Ekosistem, Ranjivost i održivost, Zapadni Balkan

  • Environmental flows and demands for sustainable water use in protected karst areas of the Western Balkans

    Zoran Stevanović, Aleksandra Maran Stevanović, Želimir Pekaš, Romeo Eftimi, Veljko Marinović (2022)
    Karst terrains cover some 30% of the Western Balkans, where rich karst aquifers represent the main source of potable water supply and ensure the development of local economies and tourism. In this “classical karst” region, there are also numerous sites or areas under different forms of protection—from those that are included in the UNESCO World Heritage list to natural monuments and landscapes that are protected by national legislation. In and around them are specific representatives of flora and fauna ...
    Karst, zaštićena područja, ekosistem, ranjivost i održivost, Zapadni Balkan

  • Keyword Extraction from Parallel Abstracts of Scientific Publications

    Slobodan Beliga, Olivera Kitanović, Ranka Stanković, Sanda Martinčić-Ipšić (2017)
    ... NLP tools for Serbian and English (Subsect. 2.2) and 46 S. Beliga et al. used evaluation methodology (Subsect. 2.3). The description of the used parallel dataset for English and Serbian languages is in Sect. 3. Section 4 presents the results, while the concluding remarks and future plans are in Sect ...
    ... node and is then used in the procedure of keyword candidate ranking and extraction [8,9]. The node in/outselectivity and generalized in/out- selectivity values are calculated from a directed weighted network as the average weight distributed on the ingoing/outgoing links of the single node and used in ...
    ... text pre- processing is needed and includes the conversion of the input text to lowercase, the removal of misspelled symbols and lemmatization. In a similar way, we pre- processed the English text: converted to lowercase and stemmed using the Porter stemmer. Stemming and lemmatization are also needed ...

  • FTIR spectroscopic study оf S-мetolachlor сorption оn inorganic and organically modified montmorillonite from Bogovina

    Lazar Kaluđerović, Zorica Tomić, Jelena Bogosavljević, Ljubomir Životić, Maja Milošević (2021)
    ... between montmorilonite and chloroacetanilide herbicide could include coordination bonds between C=O and the exchangeable cation, and/or H bonds between C=O and the hydration water bcecause C=O 333 SERBIAN SOCIETY OF SOIL SCIENCE Soils for Future under Global Challenges and C-N in this compound ...
    ... presence in soil, groundwater and surface water. Numerous methods have been developed in order to reduce herbicide mobility and protect natural water resources. The results presented in this paper show the interaction of herbicide S- metolachlor with inorganic and organically modified montmorillonite ...
    ... quartz, cristobalite and carbonate minerals. Organic montmorillonites were obtained after modification with different concentrations of organic complex (HDTMA and PTMA), whereas inorganic modification was performed with IM NaCI!I solution. The interaction between minerals and herbicide was monitored ...

  • Alpine thermal events in the central Serbo-Macedonian Massif (southeastern Serbia)

    Milorad D. Antić, Alexandre Kounov, Branislav Trivić, Andreas Wetzel, Irena Peytcheva, Albrecht von Quadt (2015)
    General Earth and Planetary Sciences

  • Age and microfacies of oceanic Upper Triassic radiolarite components from the Middle Jurassic ophiolitic mélange in the Zlatibor Mountains (Inner Dinarides, Serbia) and their provenance

    Hans-Juergen Gawlick, Nevenka Đerić, Sigrid Missoni, Nikita Bragin, Milan Sudar, Divna Jovanović (2017)
    Neo-Tethys, trench-like basins, synorogenic deposition, evolving thrust belt, Triassic palaeogeography
    ... 2009: New data on Mesozoic Radiolaria of Serbia and Bosnia, and implications for the age and cvolution of oceanic volcanic rocks in the Central and Northern Balkans. Lifhos 108, I—4, 72—105. Zuffa G.G. 1980: Hybrid arenites: thcir composition and classifi- cation. J. Sediment. Petrol. 50, 21—29 ...
    ... Sudar et al. 2013). Coarse-grained turbi- dites and mass transport deposits beside fine-grained radio- laritic-argillaceous sediments and turbidites consisting:of ophiolitic sand and radiolarites (Fig. 3) are the dominant sedi- mentary rocks and occur in fissures of the underlying. carbo- nate ...
    ... the basis of Kober (1914) concerning the genesis and emplacement of the ophiolites and related radiolaritic-ophiolitic trench fills. Ages after Cohcen et al. (2013, updated). Late Triassic shelf configuration of the Eastern and Southern Alps and the Western Carpathians modified after Gawlick et al ...

  • Life Cycle Assessment of Individual Wood Biomass Heating Systems in Households

    Boban Pavlović, Dejan Ivezić, Marija Živković (2020)
    The use of solid fuels (wood biomass and coal) for heating of households continues to be common practice within European countries. Solid fuel combustion in households contributes more than 46% to total emissions of fine particulate matter. In this study, a life-cycle assessment (LCA) of firewood-based and pellet-based heating systems is performed. These two systems represent two different types of individual wood biomass heating systems. In the case of the firewood-based heating systems, it is analyzed a typical stove ...
    Grejanje, Analiza životnog ciklusa, Drvna biomasa, Individualni sistemi grejanja
    ... heating systems in EU countries, based on efficiency and fuel cost, Renewable and Sustainable Energy Reviews, pp. 687-699. [3] WHO, World Health Organization. (2015). Residential heating with wood and coal: health impacts and policy options in Europe and North America, WHO Regional Office for Europe, ...
    ... negative impact on the environment and climate change, and at the same time, it ensures the financial benefits through savings and conservation of natural resources. This research showed that the implementation of LCA for assessing heating systems is an efficient and relatively simple method for obtaining ...
    ... Faculty of Mining and Geology, Belgrade, Serbia, marija.zivkovic@rgf.bg.ac.rs Life Cycle Assessment of Individual wood Biomass Heating Systems in Households 429 Solid heating fuels consist primarily of wood and coal but can also include forestry and agricultural residues and even municipal solid ...

  • Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry

    Steven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti (2021)
    Self-engineering is a relatively new branch of knowledge that aims to understand how systems could “autonomously” re-configure or repair themselves without the intervention of the operators. A direct field of application is within the maintenance spectrum. Having systems or machines capable of self-detecting or even self-repairing could represent a game-changer, in capital asset fields such as the mining industry in particular. This paper aims to investigate the possible benefits and challenges of self-engineering / self-maintenance concerning mining machines, specifically bucket-wheel ...
    self-engineering, self-maintenance, maintenance operations, mining industry, bucket-wheel excavator, gearbox revitalization

  • Failure Estimation of the Majdanpek Open Pit East Face Based on Inverse Velocity Model

    Miloš Marjanović, Stefan Milanović, Nikola Simić, Lazar Kričak (2024)
    The Majdanpek open pit mine south district is currently active mining prospect of copper ore exploitation in eastern Serbia. Its depth is approaching the termination depth and occurrences of large-scale instabilities and global instability of the final pit slope is possible. These can generate catastrophic mass movement inside an area that encloses a regional road route and the Pek River bed which is channelled along the outer contour of the pit. The displacements that were noted in early 2023, in the ...
    displacement, survey, inverse velocity, open pit

  • The Nooj System as Module within an Integrated Language Processing Environment

    Ranka Stanković, Duško Vitas, Cvetana Krstev (2008)
    NooJ, electronic dictionary, lexical resources
    ... Mathematics, University of Belgrade, and is aimed at manipulating heterogeneous lexical resources developed in the course of many years and within different projects. The tool handles morphological dictionaries, wordnets, aligned texts and transducers and has already proved very useful for various ...
    ... years, and it is understandable that they have been conceived within different projects and frameworks, both from the conceptual and the technological perspective. Despite that the HLT group made every reasonable effort to keep the constantly growing pool of resources as coherent and standardized ...
    ... their presentation and usage This software tool is developed in C# and operates on the .NET platform. An important feature of WS4LR is its flexibility expressed both by the possibility of setting environment parameters and by the possibility of invoking command-line routines and using external Perl ...

  • An Approach to Development of Bilingual Lexical Resources

    Stanković Ranka, Obradović Ivan, Trtovac Aleksandra (2012)
    ... lexical resources, we had at our disposal Serbian morphological e-dictionaries [Krstev, 2008], Serbian and English wordnets (SrpWN and EWN), and a bilingual Serbian-English Dictionary of Library and Information Science technology (further referred to as Dictionary of Librarianship) [Kovačević et ...
    ... the system of rules for compound inflection, finite automata and transducers, represent the basis for morphological expansion of queries. As for semantic and bilingual expansion, the system relies on Serbian and English wordnets and the bilingual dictionary of Librarianship. The user formulates ...
    ... exist in the database and if not, enters the missing terms in the database and generates the new synset. The next step, establishing a relation between a synset and its counterpart in another language, is simply realized by selecting the pair of synsets to be related, and then clicking on the ...

  • An Approach to Efficient Processing of Multi-Word Units

    Cvetana Krstev, Ivan Obradović, Ranka Stanković, Duško Vitas (2013)
    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 ...
    Natural Language Processing, Grammatical Category, Lexical Representation, MWU, multi-word unit
    ... are petokrak.A6 and zvezda.N600, and for Farenhajtov stepen they are Farenhajtov.A1 and stepen.N5. 5. What are the values of grammatical features of constituent forms used in the MWU lemma? For the first example they are aefs1g and fs1q, while for the second they are akms1g and ms1q. A fully manual ...
    ... that it enables inflection of simple words, MWUs and free phrases supplied as key- words to Google. The tool relies on Serbian e-dictionaries, inflection transducers for simple words and MWUs, and uses Unitex and Multiflex modules for inflection and dictionary look-up. As for the free phrases that ...
    ... the natural order of an adjective and a noun in a MWU. However, these MWUs, together with a few more allow a reverse order as well — zvezda petokraka and stepen Farenhajtov. Both MWUs can be used in plural form. In Serbian, adjectives and nouns inflect in number and case, while adjective forms also ...