Претрага

Упит dcterms_subject_txt:Timok Magmatic Complex

534 items

  • Mean-based iterative methods for finding multiple roots in nonlinear chemistry problems

    Dejan Ćebić, Nebojša M. Ralević (2021)
    нелинеарне једначине, поступци засновани на срединама, вишеструки корени,

  • BaTiO3/NixZn1−xFe2O4 (x = 0, 0.5, 1) Composites Synthesized by Thermal Decomposition: Magnetic, Dielectric and Ferroelectric Properties

    Marija Šuljagić, Ivan Petronijević, Miljana M. Mirković, Aleksandar Kremenović, Adis Džunuzović, Vladimir B. Pavlović, Aleksandra Kalezić-Glišović, Ljubica Andjelković (2023)
    To investigate the influence of spinel structure and sintering temperature on the functional properties of BaTiO3/NixZn1−xFe2O4 (x = 0, 0.5, 1), NiFe2O4, ZnFe2O4, and Ni0.5Zn0.5Fe2O4 were in situ prepared by thermal decomposition onto BaTiO3 surface from acetylacetonate precursors. As-prepared powders were additionally sintered at 1150 °C and 1300 °C. X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM) coupled with electron dispersive spectroscopy (EDS) were used for the detailed examination of phase composition and morphology. The magnetic, dielectric, and ...
    ferroelectric, dielectric properties, magnetic properties, titanate/ferrite composites, phase composition
    ... addresses a simple route to prepare a series of a composite o. BaTiOx /NixZni_„Fe>Oua (x = 0, 0.5, 1) via the thermal decomposition of acetylacetonate complex precursors onto BaTiOy surface and processing of obtained structures into dense ceramics. The effect of structural properties and phase composition ...
    ... trap-controlled SCLC mechanism) [80,81], the measured room-temperature leakage current density and its dependence on the static electric field in such complex composites cannot be easily interpreted. However, the presence of the ohmic conduction mechanism was undoubted for all investigated samples, Figure ...

  • Structural dissymmetrization of optically anisotropic Grs64±1Adr36±1Sps2 grandite from Meka Presedla (Kopaonik Mt., Serbia)

    Pavle Tančić, Aleksandar Kremenović, Predrag Vulić (2019)
    In this paper, grandite core with Grs64±1Adr36±1Sps2composition was crystallographically studied. This core represents zone A of the macroscopically visiblefive A–E zones of the optically anisotropic Grs58–64 Adr36–42Sps2 grandite. The applied procedure includes the detailed analysis of the powder diffraction patterns, and the Rietveld refinements of the crystal structures in a series of 18 space groups and two mixtures, which were followed by the comparative analysis of the R-values, site occupancy factors, and the bond lengths and angles. Synthesis of all ...
    grandite, XRPD, crystal structure, structural dissymmetrization

  • Developing Termbases for Expert Terminology under the TBX Standard

    https://dr.rgf.bg.ac.rs/s/repo/item-set/522 (2014)
    ... Definition: Mineral deposits are the geological bodies limited by natural or ar- tificial (industrial) borders. They are formed in the nature, through complex geological and chemical processes. As an integral part of the Earth’s crust, mineral deposits are built out of different minerals, elements and compounds ...
    ... the DELAS format (e.g. N1, N300, A2). An example of a compound term related to mining and geology, which com- prises tree simple words, in the more complex DELAC dictionary is: leziSte(lezi8te.N300:nsiq) mineralnih sirovina,NC_N4X+Comp ✶✽ ❘❛♥❦❛ ❙t❛♥❦♦✈✐➣✱ ■✈❛♥ ❖❜r❛❞♦✈✐➣✱ ❛♥❞ ▼✐❧♦➨ ❯t✈✐➣ ❚❤❡ ✜rst ...
    ... meta-model. Both and are defined by the TBX standard, but the use of the element is giving way to the element which is more complex and richer in information. Namely, besides the element, also features the element, which contains ad- ditional information ...

  • 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
    ... role of carbon utilization in transforming CO2 from a liability into an essential resource. The final section of the master thesis explores the complex domain of carbon storage and transport. The assessment of geological, oceanic, and terrestrial storage. methods underscores the importance of site ...
    ... separation involves multistage operation and streams recycling, which are often perceived as challenges that make this operation difficult and complex. Various porous inorganic membranes typically composed of zeolites, metal-organic frameworks (MOFs), carbon molecular sieves (CMS), ceramics, and ...

  • Keyword-Based Search on Bilingual Digital Libraries

    Ranka Stanković, Cvetana Krstev, Duško Vitas, Nikola Vulović, Olivera Kitanović (2017)
    This paper outlines the main features of Biblisha, a tool that offers various possibilities of enhancing queries submitted to large collections of aligned parallel text residing in bilingual digital library. Biblishsa supports keyword queries as an intuitive way of specifying information needs. The keyword queries initiated, in Serbian or English, can be expanded, both semantically, morphologically and in other language, using different supporting monolingual and bilingual resources. Terminological and lexical resources are of various types, such as wordnets, electronic ...

  • An aproach to Implementation of blended learning in a university setting

    Ivan Obradović, Ranka Stanković, Olivera Kitanović, Jelena Prodanović (2011)
    ... visited courses on the FMG Moodle platform from October 1, 2010 to August 1, 2011. The process of creating and populating a course is in general complex and time consuming, which makes course backup extremely important. A “Backup Report” gives an overview showing when each course had been archived ...

  • The Usage of Various Lexical Resources and Tools to Improve the Performance of Web Search Engines

    Krstev Cvetana, Stanković Ranka, Vitas Duško, Obradović Ivan (2008)
    In this paper we present how resources and tools developed within the Human Language Technology Group at the University of Belgrade can be used for tuning queries before submitting them to a web search engine. We argue that the selection of words chosen for a query, which are of paramount importance for the quality of results obtained by the query, can be substantially improved by using various lexical resources, such as morphological dictionaries and wordnets. These dictionaries enable semantic ...
    LR web services, MultiWord Expressions & Collocations, Information Extraction, Information Retrieval
    ... expansion. Figure 1. WS4QE home page The user can choose from several options for query expansion, the wordnet advanced search being the most complex. Figure 2 shows the page for this type of search with the word beli luk in Latin alphabet chosen as the initial search string. As semantic expansion ...

  • Mine surveying works for the purpose of excavating the remaining reserves of bauxite in the deposit of “Podbracan”

    Aleksandar Milutinović, Aleksandar Ganić, Thamer Rayes Diyab, Rade Tokalić, Meri Ganić (2015)
    ... of the open pit. At the �rst stage of the project, the lowest bench, planned to be exited to, is located at the level +420m. This is the longest complex of the designed underground chambers, whose spatial length is d k =743.52m, and total horizontal length is d=739.73m. The total of 54 points ...

  • Debris-flow Susceptibility Assessment in Flow-R: Ribnica River Case Study

    Ksenija Micić, Miloš Marjanović, Biljana Abolmasov (2024)
    Debris flows are among the most dangerous erosional geohazards due to the fast rate of movement and long runout zones. Even though the initiation can be triggered in mountainous areas, inhabited and with steep slopes, their propagation and deposition can endanger not only buildings and infrastructure in the urbanized areas, but also threaten human lives. As these initiation areas usually represent unattainable terrains with rapid vegetation cover development, field observations and aerial photo analysis become high-demanding tasks. Consequently, medium-to-regional ...
    tečenje drobine, Flow-R, procena podložnosti, empirijski model

  • Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2017)
    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 ...
    ... roles) are underlined with a double line, organi- zation names are framed. Determination of weights for terms within the indexes of a document is a complex process and there are numerous models, the most used being: tf based on the term frequency in the document index, idf which A u t h o r P r o ...
    ... Another evaluator remarked that although the initial system performs well for some simple queries, it often gives completely erroneous results for complex ones. If assessed, the ini- tial system would have a mark of 2 and the improved a 6, in comparison to Google Search with a mark of 10. 6 For the initial ...

  • Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine

    Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović (2019)
    Availability is one of the most used terms in maintainability engineering. This concept is used to denote: The quality of service of an engineering system, i.e., machines, weak points’ analysis, asset management, as well as making decisions in the process of life cycle management. Availability is an overall indicator and contains partial indicators that are oriented towards reliability, maintenance, and logistical support. Availability presents a variable value and changes in time and space. Usually, availability is shown as the ...
    raspoloživost, fazi teorija, AHP višekriterijumska analiza, eksperska ocena, buldozer
    ... (4) and (5). To determine availability in this way, an appropriate IT structure for keeping track of time ti is required. In real terms related to complex machine engineering systems, this condition is usually not fulfilled or only partially fulfilled. Another problem is that we cannot infer the availability ...
    ... decisions can be made when there are only two alternative choices in one interaction. This is precisely the basic principle of the AHP method [22]. A complex problem is split into simple factors that are then compared in pairs. Each pair comparison is made using the Saaty scale of relative importance shown ...

  • Sorpcija herbicida na neorganski i organski modifikovanom prirodnom montmorionitu iz Bogovine

    Lazar M. Kaluđerović (2018-01-17)
    fikasnost prilikom sorpcije S-metolahlora i klomazona od strane neorganskih iorganski modifikovanih montmorionita sa lokaliteta Bogovina odreĎena je metodombach adsorpcije. Uzorci montmorionita su tretirani prvo rastvorom NaCl a zatim irazličitim koncentracijama organskih kompleksa. Adsorpcione izoterme su dobijenetretiranjem uzoraka različitim koncentracijama herbicida. Detaljna mineraloškakarakterizacija uzoraka uraĎena je metodom rendgenske difrakcije. Rezultati interakcijemontmorionita sa organskim kompleksima i herbicidima dobijeni su primenomrendgenskih, optičkih, termičkih i spektroskopskih metoda.Na osnovu rezultata rendgenskih ispitivanja uzoraka, utvrĎeno je prisustvoorganskih kompleksa i herbicida u meĎuslojnom prostoru montmorionita.Montmorioniti modifikovani ...
    adsorpcija, montmorionit, heksadeciltrimetilamonijum bromid,feniltrimetilamonijum hlorid, S-metolahlor, klomazon
    ... that all examined organic complexes and herbicides intercalated into interlayer space of montmorillonite. Montmorillonites modified with HDTMA complex exhibited monolayer, bilayer and pseudotrilayer arrangement of HDTMA+ cations in interlayer space, depending on degree of saturation. It has been ...
    ... are forming the partition phase for the herbicide on the surface of the montmorillonite. On the other hand, montmorillonite modified with PTMA complex exhibited monolayer arrangement of cations on the surface of montmorillonite in such a way that the cations act as pillars in interlayer space ...
    ... adsorbed on the surface of the montmorillonite. Which functional groups were involved in bonding processes between montmorillonite, organic complex and herbicide best describes infrared spectroscopy. High sorption of examined herbicides on some organic modified montmorillonites creates an ...

  • Rezultati ispitivanja parametara čvrstoće i dinamičkih svojstava mermera i mogućnost njihove korelacije

    Jelena Majstorović-Necković, Vladimir Čebašek, Veljko Rupar (2023)
    Ispitivanja stena kao radne sredine, odnosno materijala sa kojim se gradi, na kome se gradi i u kome se gradi, svojom složenošću zahteva njeno svestrano izučavanje po velikom broju parametara. Zadatak Mehanike stena je da što bolje upozna ponašanje stenske mase i njenu otpornost na dejstvo pritiska, zatezanja i smicanja, kao i dinamičkih svojstava. Poznavanje navedenih parametara i njihova korelacija omogućavaju pouzdaniji izbor parametara za projektovanje danas sve zahtevnijih uslova kako podzemne, tako i površinske eksploatacije. U ovom radu ...
    mermer, jednoosna čvrstoća na pritisak, čvrstoća na istezanje, brzina longitudinalnih elastičnih talasa, korelacija

  • Hronološki pregled razvoja površinske eksploatacije lignita u Srbiji

    Bojan Dimitrijević, Radmila Gaćina, Bogoljub Vučković (2023)
    U ovom preglednom radu dat je istorijski pregled razvoja površinske eksploatacije lignita na teritoriji Srbije, uz kratak osvrt na geološki nastanak i kvalitet i rezerve uglja, kao i mogućnosti korišćenja za dalju upotrebu. Kolubarski, Kostolački i Kovinski ugljeni baseni lignita u Srbiji, ne računajući Kosovsko-Metohijski i Drenički u sastavu AP Kosovo i Metohija po Rezoluciji 1244 UN, su ležišta najrasprostranjenijeg uglja - lignita u Srbiji koji se eksploatiše od druge polovine 20. veka na velikom broju površinskih kopova ...
    površinska eksploatacija ugalja, lignit, Kolubara, Kostolac, Srbija

  • Indexing of textual databases based on lexical resources: A case study for Serbian

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2015)
    In this paper we describe an approach to improvement of information retrieval results for large textual databases by pre-indexing documents using bag-of-words and Named Entity Recognition. The approach was applied on a database of geological projects financed by the Republic of Serbia in the last half century. Each document within this database is described by metadata, consisting of several fields such as title, domain, keywords, abstract, geographical location and the like. A bag of words was produced from these ...
    ... which recognized NEs are highlighted: locations in blue, persons in pink, and organizations in light green. Determination of term weights is a complex process and there are numerous models, the most used being: idf based on the term frequency in the document, probabilistic, which includes in addition ...

  • Determining the Groundwater Balance and Radius of Influence Using Hydrodynamic Modeling: the Case Study of the Groundwater Source “Šumice” (Kikinda, Serbia)

    Dušan Polomčić, Dragoljub Bajić, Jelena Zarić (2015)
    A groundwater flow model was developed to simulate groundwater extraction from the public water supply source of the City of Kikinda. The hydrodynamic model includes the municipal groundwater source of Kikinda (Šumice and the Jezero Well), but also an extended area where there are groundwater sources that provide water supply to three factories: (MSK, TM and LŽT - Kikinda). Hydrodynamic modeling, based on the numerical method of finite differences will show the groundwater balance of the sources in the ...
    Water supply, Aquifer, Flow, Groundwater regime, Numerical modeling, Particle tracking
    ... Development of Energy, Water and Environment Systems Year 2015 Volume 3, Issue 3, pp 217-229 218 Nowadays, water supply is a highly complex and significant issue in every society. It is of vital importance to control and monitor the operation of each water source. Unfortunately, there ...

  • Uticaj geološke neizvesnosti u razvoju rudarskih projekata

    Petar Marković, Dejan Stevanović, Mirjana Banković (2023)
    Rudarstvo je industrija koja se nosi sa različitim vrstama neizvesnosti i rizika zbog svoje prirode i specifičnosti. Neizvesnost u rudarstvu može poticati iz različitih izvora i uticati na različite aspekte rudarskih projekata. Kao jedan od dominantnih faktora, ističe se geološka neizvesnost. Geološka neizvesnost igra ključnu ulogu u rudarstvu i može značajno uticati na procenu resursa i rezervi, planiranje eksploatacije, ekonomsku isplativost i upravljanje rizicima. Ova neizvesnost se ne može eliminisati, ali se uz primenu adekvatnih standarda i zakona može ...
    ... od 19. oktobra 1979. [17] R. Goodfellow, R. Dimitrakopoulos. (2013). Algorithmic integration of geological uncertainty in pushback designs for complex multi-process open pit mines. Mining Technology , 122 (2), 67-77. [18] Royer PS. (2000). Risk Management: The Undiscovered Dimension of Project ...

  • Some examples of interactions between certain rare earth elements and soil

    Zlatko Nikolovski, Jelena Isailović, Dejan Jeremić, Sabina Kovač, Ilija Brčeski (2021)
    Freundlich adsorption isotherm, sequential extraction, metallic ions, ICP-OES
    ... The suitability of the method presented is reflected in its simplicity, namely the rare earth elements ions can be extracted by this method from a complex matrix. The environment contamination on the occasion of these elements production is evident. Excepting their natural occurrence, the anthropogenic ...

  • Primena digitalne fotogrametrije u rudniku Rudnik

    Nikola Mirković, Luka Crnogorac, Katarina Urošević (2023)
    Digitalna fotogrametrija, lasersko skeniranje i virtuelizacija sve više pronalaze aktivne uloge u rudarstvu, prvenstveno zbog svoje široke mogućnosti primene. Laserskim skeniranjem i fotogrametrijom snimaju se i kreiraju 3D modeli otkopa, jamskih hodnika, površinskih kopova, površinskih objekata (zgrada, spomenika, predmeta), a vrši se skeniranje celih rudnika koji se rekonstruišu u 3D digitalne modele. Fotogrametrija predstavlja proces fotografisanja objekata pomoću fotoaparata i daljom obradom fotografija u različitim softverskim alatima kreiraju se realne kopije 3D modela objekata ili predmeta u digitalnoj formi. Za ...
    digitalna fotogrametrija, prostorna vizuelizacija, rudarski objekti, podzemna eksploatacija
    ... J. A., Pedraza, O., Magnusson, G., Nufiez-Andrćs, M. A., & Franklin, K. (2022). Using Mixed Reality for the Visualization and Dissemination of Complex 3D Models in Geoscience -– Application to the Montserrat Massif (Spain). Geosciences, 12(10), 370 [6] Petar Jovanović (2007) Rudarstvo na tlu Srbije ...