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Упит dcterms_subject_txt:Behavior and Systematics,Oceanography

2347 items

  • Application of machine learning for diagnosing the operation of a deep well pump in oil production

    Maja Trikić (2024)
    This paper will thoroughly examine how machine learning can improve the diagnosis of deep well pumps by analyzing the role and function of the pumps, dynamograms, sensor technologies, and diagnostic methods.Our analysis will provide insights into modern techniques and approaches for enhancing the performance and reliability of oil production systems, targeting cost reduction and increased operational efficiency.
    deep well pump, dynamograms, machine learning, diagnostics of operating coditions,Random Forest, XGBoost
    ... values for the smooth rod stroke and load, dimensions and characteristics of the downhole pump, the kinematic assembly of the horsehead, and the characteristics of the sucker rods.To develop a mathematical model for a smart transmission system for diagnosing well behavior in deep well pumping, the following ...
    ... weight, and maximum Stresses. 4. A database of basic geometric dimensions of downhole pumps necessary for calculating baseline theoretical dynamograms. 10 All these complex databases are integrated into the knowledge base of the intelligent computing. system for diagnosing well behavior in deep ...
    ... Testing and Refining - Finally, we would test our program and iterate through steps 1 and 2, refining the rules and algorithms until we achieve satisfactory results. 17 This approach can be time-consuming and requires a lot of manual effort, as rules need to be constantly updated and adjusted ...

  • Using technology for knowledge transfer between academia and enterprises

    Ivan Obradović, Ranka Stanković (2014)
    ... thematic content, and entrepreneurial: case studies, best practice examples, expert presentations and software demonstrations. Language resources supporting the multilinguality of the platform, terminology and its search and browse functions are lexical and textual resources and grammars. Impl ...
    ... contributes to improvement and enhancement of relations between the academia and the enterprises and integration of creative research potential with industry and academic institutions. The second objective within our project is to develop and implement guidelines and procedures for quality assurance ...
    ... initiative, where materials are offered openly and freely to educators, students, and self-learners to use and reuse for teaching, learning, and research (Bissell, 2009). The materials are released under an open source license which permits their use, reuse and redistribution with limited or no restrictions ...

  • Differently shaped nanocrystalline (Fe, Y)3O4 and its adsorption efficiency toward inorganic arsenic species

    Biljana P Dojčinović, Boštjan Jančar, Lotfi Bessais, Aleksandar Kremenović, Nataša P Jović-Jovičić, Predrag T Banković, Dalibor M Stanković, Miloš Ognjanović, Bratislav V Antić (2019)
    Herein we report effects of partial substitution of Fe3+ by Y3+ in magnetite (Fe3O4) on morphology and inorganic arsenic species adsorption efficiency of the Fe3−xYxO4 nanoparticles formed. The series of Fe3−xYxO4 (x=0.00, 0.042 and 0.084, labeled as Y00, Y05 and Y10, respectively) was synthesized using co-precipitation followed by microwave-hydrothermal treatment (MW) at 200°C. With increase of yttrium content(xvalue), both the morphological inhomogeneity of the samples and the fraction of spinel nanorods as compared to spinel pseudospherical particles increased. By ...
    microstructure, microwave-hydrothermal synthesis, adsorption, magnetic nanoparticles, arsenic

  • A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)

    Jelena Ratković, Dušan Polomčić, Dragoljub Bajić, Bojan Hajdin (2016)
    ... Belgrade (Fig. 1) and encompasses the area around the middle and lower courses of the Kolubara River and its tributaries: the Tamnava (left) and the Peštan (right). Tamnava – West Field falls within the municipalities of Lajkovac and Ub, near the villages of Kalenić, Mali Borak, Radljevo and Skobalj. To ...
    ... sand and clay); dpr - diluvial/proluvial sediments; am - oxbow sediments (mud and clay); t1 - lower river terrace; Q, Pl - riverine-lacustrine terrace; Pl1 - sand and clay (marly and coaly) There is a triple aquifer system in the extended zone of the study area: upper, intermediate and lower ...
    ... geological and hydrogeological research. In essence, the hydrogeologic model shows the types of rocks, from a hydrogeological perspective, and their geometry. The focus is on aquifers and their spatial relationships. Groundwater levels, directions of groundwater flow, and recharge and discharge zones ...

  • Fragmentation Size Prediction of Blasted Material Using a Specialized Software for Drilling and Blasting

    Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić, Miljan Gomilanović (2024)
    Design and optimizing the drilling and blasting parameters, should fill the requirements for the capacity, fragmentation size, and technical characteristics of loading and transport equipment, and enable a safe work at the open pit. Besides mentioned, it also achieves the minimal impact on the environment of the open pit and decreases the negative effects on the environment, especially in the blast vibration and flyrock. To obtain the best possible blasting effects and consider all the factors, a specialized software is ...
    optimization, O-Pitblast, drilling, blasting, fragmentation size

  • Towards Semantic Interoperability: Parallel Corpora as Linked Data Incorporating Named Entity Linking

    Ranka Stanković, Milica Ikonić Nešić, Olja Perisic, Mihailo Škorić, Olivera Kitanović (2024)
    U radu se prikazuju rezultati istraživanja vezanih za pripremu paralelnih korpusa, fokusirajući se na transformaciju u RDF grafove koristeći NLP Interchange Format (NIF) za lingvističku anotaciju. Pružamo pregled paralelnog korpusa koji je korišćen u ovom studijskom slučaju, kao i proces označavanja delova govora, lematizacije i prepoznavanja imenovanih entiteta (NER). Zatim opisujemo povezivanje imenovanih entiteta (NEL), konverziju podataka u RDF, i uključivanje NIF anotacija. Proizvedene NIF datoteke su evaluirane kroz istraživanje triplestore-a korišćenjem SPARQL upita. Na kraju, razmatra se povezivanje Linked ...
    paralelni korpusi, povezivanje imenovanih entiteta, prepoznavanje imenovanih entiteta, NER, NEL, povezani podaci, NIF, Vikipodaci

  • Composition of organic matter and thermal maturity of Mesozoic and Cenozoic sedimentary rocks in East Herzegovina (External Dinarides, Bosnia and Herzegovina)

    Nikoleta Aleksić, Aleksandar Kostić, Miloš Radonjić (2021)
    This paper presents the first data on the organic matter and thermal maturity of Mesozoic and Cenozoic sedimentary rocks in the East Herzegovina region of the External Dinarides. Representative, organic-rich samples from outcropping sedimentary rocks of different ages in the area (Triassic to Neogene) were selected and analysed. The organic matter was studied by Rock-Eval pyrolysis and under the microscope in reflected non-polarized light and incident blue light. The results obtained show the presence of different types of organic ...
    nafta i gas, Rock-Eval, refleksija vitrinita, maceral, termička zrelost
    ... Middle and Late Jurassic strata are composed of oolithic limestones, reef and lagoonal shallow-water limestones, and dolomites (Natević and Petrović, 1970; Mirković, et al., 1974). Similar rocks of Cretaceous age cover larg- er parts of the study area (Mojićević and Laušević, 1965; Natević and Petrović ...
    ... Middle and Late Jurassic strata are composed of oolithic limestones, reef and lagoonal shallow-water limestones, and dolomites (Natevi¢ and Petrovi¢é, 1970; Mirkovic, et al., 1974). Similar rocks of Cretaceous age cover larg- er parts of the study area (Moji¢evi¢ and LauSevic, 1965; Natevi¢ and Petrovi¢ ...
    ... 1978. Petroleum Formation and Occurrence: A New Approach to Oil and Gas Exploration. Springer-Verlag, Berlin, 538 pp. Van Gijzel, P., 1981. Characterization and identi�cation of kerogen and bitumen and determination of thermal maturation by means of qualitative and quantitative microscopical ...

  • Properties of fly ash and slag from the power plants

    Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić (2016)
    This paper describes the physical, chemical and mineral properties of ash and slag, which were taken from thermal power plants Nikola Tesla A, Nikola Tesla B, Kostolac A and Kostolac B. The knowledge of the mineralogical material composition is important because the type of minerals directly determines the properties of the fly ash and slag and their possible application. Laboratory tests showed that ash and slag samples consist of the following minerals: amorphous materials, quartz, feldspar, mullite, melilite, cristobalite, ...
    fly ash, slag, physical composition, chemical composition, mineral composition, X-ray diffraction method
    ... new approach for the classification of coal fly ashes based on their origin, composition, properties, and behavior.– Fuel, 86, 1490–1512. WARD, C. & FRENCH, D. (2005): Relation between Coal and Fly Ash Mineralogy, Based on Quantitative X-Ray Diffraction Methodos. 2005 World of Coal Ash, In- ternational ...
    ... in the combustion process and other parts of non- combustible material. It falls through the latticed stokehole and is rapidly cooled and extinguished in water. The fly ash and slag landfills in Serbia occupy an area of 1639 ha and if they are under constant control and monitoring, significantly ...
    ... the Kostolac basin is also of Upper Miocene (Pontian) age and hosts five coal seams, namely Seam III (the oldest and deepest) and Seams II-a, II, I-a and I. Only coal seams III, II and I are (or have been) explored in the Drmno, Ćirikovac and Klenovnik open pits. The average thickness of coal Seam ...

  • GIS Application Improvement with Multilingual Lexical and Terminological Resources

    Ranka Stanković, Ivan Obradović, Olivera Kitanović (2010)
    ... expands into only 10 combinations of an adjective form and a noun form: kvarcna stena AND kvarcne stene AND kvarcnoj steni AND kvarcnu stenu AND kvarcna steno AND kvarcnom stenom AND kvarcnoj steni AND kvarcnih stena AND kvarcnim stenama AND kvarcnima stenama thus disabling false retrieval ...
    ... geologic multilingual vocabulary and other lexical and terminological resources used. Two basic results are outlined: multilingual map annotation and improvement of queries for the GeolISS geodatabase. Multilingual labelling and annotation of maps for their graphic display and printing have been tested with ...
    ... data records and measurements, the basis for classification, interpretation and modeling of geological features. Spatial entity is treated as observation location and mapped/interpreted geological occurrence, and implemented in the geodatabase geometrically by points, lines and polygons. This ...

  • Optimization and Analysis of Drilling and Blasting Parameters Using O-Pitblast Software

    Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić (2024)
    The development of modern technologies has enabled the application of specialized softwares in the field of mining through various segments and processes, including in works related to drilling and blasting. The application of specialized software for drilling and blasting with the use of modern technologies such as photogrammetry enabled more accurate data from the field for later processing. By processing data and creating a 3D model of the terrain for drilling and blasting works, it can obtain precise data, ...
    optimizacija, 3D model, bušenje, miniranje, O-Pitblast, softver

  • Development of terminological resources for expert knowledge: a case study in mining

    Ljiljana Kolonja, Ranka Stanković, Ivan Obradović, Olivera Kitanović, Aleksandar Cvjetić (2015)

  • Geochemical study of U, Th and REE mineralizations in Jurassic sediments and hydrochemical characterization of groundwaters in Eastern Serbia – Case study: Plavna area

    Jovan Kovačević, Maja Todorović, Marina Ćuk, Petar Papić (2016)
    jurski sedimenti, uran, torijum, elementi retkih zemalja, podzemna voda, istočna Srbija

  • 3D modeling and monitoring of karst system as a base for its evaluation and utilization: a case study from eastern Serbia

    Saša Milanović, Zoran Stevanović, Ljiljana Vasić, Vesna Ristić-Vakanjac (2013)
    Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • Analysis Of the Process Of Carbon Capture Utilization And Storage In Underground Reservoirs

    John Nyame (2024)
    The importance of mitigating the effects of global climate change has necessitated an in-depth exploration of innovative strategies to reduce carbon dioxide (CO2) emissions. Among these strategies, Carbon Capture, Utilization, and Storage (CCUS) has emerged as a promising and transformative solution. This master thesis delves into the diverse realm of CCUS processes, aiming to unravel the positives challenges, and opportunities within this dynamic field. The analysis begins with a systematic examination of carbon capture technologies, encompassing post-combustion, pre-combustion, and oxy-fuel combustion ...
    Carbon Capture, Utilization and Storage
    ... phase behavior, density, and viscosity of CO:> and CO-»- containing mixtures in the design of the pipeline [84]. Carbon dioxide is likely to be transported in its dense phase (phase temperatures usually around 31.1%C and above critical pressures) in pipelines due to pipeline diameter and costs ...
    ... reservoir [66]. Oil displacement is dependent on the phase behavior of CO» and crude oil mixtures that are strongly dependent on reservoir temperature, pressure and crude oil composition. These mechanisms range from oil swelling and viscosity reduction for injection of immiscible fluids (at low ...
    ... to be found suitable and safe to store the 25 Mt CO. Before injection started, the storage formation and expected CO» behavior was studied. The extra installations needed to handle the CO» coming from the capture unit were compressor trains including gas turbine drives, and an injection well. ...

  • ‘Blue-’ and ‘Brown-speckled’ pottery from Qalhât, the Sultanate of Oman (13–16th centuries): Comparison with traditional Omani 19–20 century productions

    Liliana Gianni, Hélène Renel, Aleksandar Kremenović, Philippe Colomban (2020)
    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 ...
    Firing, Glaze, Traditional ceramics, Provenance studies, Augite

  • Development of Open Educational Resources (OER) for Natural Language Processing

    Cvetana Krstev, Biljana Lazić, Ranka Stanković, Giovanni Schiuma, Miladin Kotorčević (2015)
    In this paper we present the development of an online course at the edX BAEKTEL platform named “Lexical Recognition in the Natural Language Processing (NLP)”. It is based on the course of the same name for PhD studies at the University of Belgrade, Faculty of Philology. There are not many courses in Computational Linguistics (CL) on OER platforms, and there is none in Serbian either for CL or NLP. We have developed this course in order to improve this ...
    E-Learning, Open Educational Resources, Computational Linguistics, Lexical Resources, edX
    ... morphology, and syntax. Some of the functions are:  developing and applying electronic dictionaries of simple words and multi-word units;  pattern matching with queries in form of regular expressions and graphs;  text transformations;  processing of monolingual and bilingual texts ...
    ... conditions in terms of cultural and educational needs. [1] Within BAEKTEL (Blending academic and entrepreneurial knowledge in technology enhanced learning) project an open education platform is being developed, for collecting and sharing resources among academic and entrepreneurial institutions ...
    ... 2. COMPUTATIONAL LINGUISTICS AND NATURAL LANGUAGE PROCESSING Computational linguistics (CL) is a theoretical discipline between linguistics and computer science concerned with understanding and modelling the written and spoken language from a computational aspect.[3]Natural ...

  • Terminological and lexical resources used to provide open multilingual educational resources

    Biljana Lazić, Danica Seničić, Aleksandra Tomašević, Bojan Zlatić (2016)
    Open educational resources (OER) within BAEKTEL (Blending Academic and Entrepreneurial Knowledge in Technology enhanced learning) network will be available in different languages, mostly in the languages of Western Balkans, Russian and English. University of Belgrade (UB) hosts a central repository based on: BAEKTEL Metadata Portal (BMP), terminological web application for management, browse and search of terminological resources, web services for linguistic support (query expansion, information retrieval, OER indexing, etc.), annotation of selected resources and OER repository on local edX ...
    otvoreni obrazovni resursi, leksički resursi, obrada prirodnih jezika, terminologija
    ... (NLP) has a two-faceted approach to education where one involves e-learning and computer-assisted learning and instruction and the other consists of NLP tools for analysis and use of language by machines [1]. The usage and application of the research done in the field of the NLP has been present ...
    ... insufficient interaction and feedback. These tools help overcome these hurdles at an advantage for both students and educators. The model of digital education also allows for a modern peer-to-peer education where students educate themselves and each other, exploring, developing and building skills without ...
    ... engineering and statistics, as we go more in-depth, experts from more narrow fields are required. For example, NLP tools for language learning must connect to Second Language Acquisition (SLA) and Foreign Language and Teaching (FLTL) research with insights from Cognitive Psychology and Empirical ...

  • Correlation Between Dynamic CBR and Compaction and Bearing Capacity of Pavement Foundation Layers

    Milan Bogdanović, Snežana Bogdanović, Dragoslav Rakić, Irena Basarić Ikodinović (2024)
    This paper presents a dynamic California Bearing Ratio (CBRd) device that can be used on a prepared pavement foundation layer to obtain a certain parameter of the tested material in the laboratory and in situ in a direct and fast way. For the selected natural material (gravel), it is shown that the laboratory CBRd can be used to estimate the compaction and bearing capacity, because it correlates well with the parameters of the standard and modifed Proctor compaction tests. ...
    korelacija parametara, donji slojevi saobraćajnica, laboratorijska i terenska ispitivanja, dinamički kalifornijski indeks nosivosti CBRd
    ... BETWEEN DYNAMIC CBR AND COMPACTION AND BEARING CAPACITY OF PAVEMENT FOUNDATION LAYERS UDC 624.158 M. Bogdanović,!* S. Bogdanović,? D. Rakić,? and I. B. ikodinović? !TPA for quality assurance and innovation, Belgrade, Serbia, ?University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia ...
    ... the strength of a material, and depends on factors such as the grain size distribution, shape, and roughness of the grain, water content, and compaction, and can be expressed in the range of 20% < CBR, < 150% [6]. A CBR, test can be performed in the laboratory (CBR,) and in situ (CBR+p) (Fig. 1). ...
    ... Dynamic CBR and Compaction and Bearing Capacity of Pavement Foundation Layers Milan Bogdanović, Snežana Bogdanović, Dragoslav Rakić, Irena Basarić Ikodinović Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Correlation Between Dynamic CBR and Compaction and Bearing ...

  • 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 (2024)
    multi-criteria decision-making, definition of criteria, underground exploitation

  • Determination of Mechanical Properties of Altered Dacite by Laboratory Methods

    Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović (2021)
    This paper presents a methodology for determining the uniaxial and triaxial compressive strength of heterogeneous material composed of dacite (D) and altered dacite (AD). A zone of gradual transition from altered dacite to dacite was observed in the rock mass. The mechanical properties of the rock material in that zone were determined by laboratory tests of composite samples that consisted of rock material discs. However, the functional dependence on the strength parameter alteration of the rock material (UCS, intact ...
    Geology, Geotechnical Engineering, Engineering Geology
    ... Composite Rock Material with respect to Shale Thickness Ratio and Moisture Content. Electron. J. Geotech. Eng. 2008, 13, 1–10. 5. Liu, J.; Wang, E.; Song, D.; Wang, S.; Niu, Y. Effect of rock strength on failure mode and mechanical behavior of composite samples. Arab. J. Geosci. 2014, 8, 4527–4539. ...
    ... stability analysis and detailed design solutions. Author Contributions: Conceptualization, V.R.; methodology, V.R. and V.Č.; validation, V.M., D.S. and N.Ž.; formal analysis, V.R. and V.Č.; investigation, V.R., V.Č., V.M., D.S. and N.Ž.; resources, V.R. and V.Č.; data curation, V.M., D.S. and N.Ž.; writ ...
    ... specimens and discs were then cut, polished, and shaped to the required height and diameter ratio with tolerances according to the American Society for Testing and Materials—ASTM [17] (Figure 3). Due to the previously shown procedure, monolithic rock material (100% D and 100% AD) specimens and discs of ...