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Упит dcterms_subject_txt:fragmentation size

323 items

  • Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites

    Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković (2023)
    To investigate the effect of synthesis procedure and sintering temperature on the functional properties of perovskite/spinel ceramics, BaTiO3/CoFe2O4 composites were prepared by thermal decomposition, coprecipitation, and microemulsion method, and sintered at 1150°C and 1300°C. The phase composition and morphology of as-prepared powders as well as sintered ceramics were thoroughly examined by X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM) coupled with electron dispersive spectroscopy (EDS). The dielectric and ferroelectric measurements were performed in detail. Generally, the ...
    Perovskite/spinel ceramics, Multiferroic, Sintering, Influence of synthesis method

  • 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

  • Optimizacija faznog razvoja Površinskog kopa Ciganuša – Škorac u cilju definisanja dugoročne dinamike eksploatcije

    Dejan Stevanović, Petar Marković, Mirjana Banković, Milan Živković (2022)
    Definisanje dugoročne dinamike razvoja rudarskih radova koja je u potpunosti usaglašena sa strateškim ciljevima Investitora, veoma je zahtevan zadatak, koji vrlo često podrazumeva veliki broj ograničenja. Adekvatno definisana dinamika razvoja rudarskih radova treba da obezbedi dugoročne zahteve u pogledu kapaciteta, kvaliteta i raspodele resursa neophodnih za ispunjavanje strateških ciljeva, koji se po pravilu svode na ostvarenje maksimalnog profita. Uspešno definisanje dinamike eksploatacije (posebno kod metaličnih ležišta) u najvećoj meri zavisi od optimizacije faznog razvoja površinskog kopa, odnosno od pravilnog ...
    dinamika razvoja, faze razvoja, optimizacija kopa, strateški ciljevi, Whittle

  • An example of karst catchment delineation for prioritizing the protection of an intact natural area

    Vesna Ristić Vakanjac, Zoran Stevanović, Aleksandra Maran Stevanović, Boris Vakanjac, Marina Čokorilo Ilić (2015)
    Проучавано је карстни извор Перућац као главни дрен подручја планине Таре у западној Србији у циљу процене његовог режима отицања, резерви воде и дефинисања његове сливне површине. Извор се налази у североисточној, унутрашњој зони класичног динарског крша, коју карактерише доминантно проширење висококарстификованих тријаских кречњака, слабо развијена хидрографска мрежа са много понора и густе шуме. Тара је један од пет националних паркова у Србији. Циљ рада је био да се идентификује заштитна зона високог приоритета у оквиру очуваног природног подручја ...
    карстна издан, сливна површина, делинеација, заштита, менаџмент

  • Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention

    Milica Ješić, Bojan Martinović, Stefan Stančić, Miroslav Crnogorac, Dušan Danilović (2023)
    Gas wells, particularly those situated onshore, play a vital role in the global energy sector by supplying a significant portion of natural gas. However, operational challenges, notably gas hydrate formation, pose substantial issues, leading to complications such as flowline blockages and unexpected well shutdowns. Gas hydrates, crystalline structures resembling ice, ...
    Gas Well, Gas Hydrate Formation, Well Modeling, Well Performance Optimization, Choke Position Adjustments, Methanol Injection

  • Atmospheric exposure vs burying: influences on damage intensity of built-in kersantite in the monument of the Small Staircase (Belgrade, Serbia)

    Nevenka Novaković, Predrag Dabić, Vesna Matović (2023)
    Proučavan je efekat „zatrpanog kamena“ na intenzitet procesa degradacije prisutnih na kersantitu koji je ugrađen u spomenik Malo stepenište. Istraživanja su vršena na uzorcima stene iz kamenoloma i na oštećenim kamenim blokovima ugrađenim u spomenik. Dok su neki delovi stepeništa bili pod zemljom 90 godina, većina kamenih elemenata je bila izložena različitim uslovima sredine i antropogenim uticajima. Urađeno je detaljno mapiranje trenutnog stanja spomenika kako bi se istražio uticaj “zatrpavanja” i kompleksne geometrije spomenika na tip propadanja i variranje ...
    Raspadanje, Indeks oštećenja, Zatrpavanje, Fizička svojstva, Kersantit

  • Medical Domain Document Classification via Extraction of Taxonomy Concepts from MeSH Ontology

    Mihailo Škorić, Mauro Dragoni (2019)
    This paper is a result of a task that was presented to attendants of Keyword Search in Big Linked Data summer school, that was organized by Vienna University of Technology, under the Keystone COST action in the summer of 2017. It presents a specific approach to the classification via creation of minimal document surrogates based on the US National medical library’s MeSH ontology, which is derived from the Medical Subject Headings thesaurus. In a series of previously classified medically ...
    document classification, MeSH, ontology, information extraction
    ... [0-9]([.][0-9][0-9][0-9])*)|([0-9]+[.]txt)|([\r\n]+), док се све остало уклања.while everything else is removed. This reduced the file size over 450 times (new size: ∼0.5MB). Upon completion of the transformation, a new file is formed. In it, each new line represents a new document: it begins with the ...
    ... values. The concept names are derived from the rdfs:label, followed by the mesh:treeNumber of the same concept. The returned concepts are sorted by the size of the name from the longest to the shortest, in order for them to be searched in the documents without the risk of longest matches not being recognized ...
    ... the documents from the rest of the unpaired text. To prevent this from working individually for each document, they are merged into one, ∼230MB, in size, with new lines as the border between the documents. Information of importance – doc- ument names ([0-9]+[.]txt), identifiers in them ([A-Z][0-9][0-9]([ ...

  • Single and multi-phase inclusions in garnets from the Lešnica alluvion in the Internal Dinarides, Serbia

    Maja Milošević, Bojan Kostić (2021)
    ... usually incorporate REE (titanite,apatite, and zircon) together with uranium oxide minerals. Other single-phase inclusions are oftenquartz and rutile. Size of inclusion varieties from grain to grain, between 5 and 40 µm, while theirdistribution doesn’t follow any pattern, random distribution. It has been ...

  • Значај петрографске анализе флуидних инклузија

    Стефан Петровић, Милош Велојић (2022)
    У раду је истакнут значај петрографске анализе током истраживања флуидних инклузија и приказане могућности ове методе на примерима неких од карактеристичних петрографских појава из различитих минерала. Петрографска анализа је први корак у испитивању флуидних инклузија. Правилно спроведена, петрографска анализа омогућава одређивање генетске везе флуидних инклузија и минерала домаћина, препознавање карактеристика флуидних инклузија и релевантну интерпретацију података из наредних корака истраживања. Петрографском анализом се дефинишу: а) дистрибуција флуидних инклузија у минералу; б) облик, величина и фазни састав флуидних инклузија; в) групације ...
    петрографија, флуидне инклузије, флуиди, групације

  • Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia

    Bojan Kostić, Pavle Tančić, Natalija Batoćanin (2024)
    geohemija granata, retke zemlje, fluidne inkluzije, skarnovsko ležište Rudnik

  • Evaluation And Perspectives Of Underground Coal Mines In Serbia

    Vladimir Milisavljević, Milena Lekić, Ivica Ristović, Vojin Čokorilo, Aleksandar Cvjetić (2017)
    ... score is given in relation to existing A and B amounts of reserves (criteria C1); • Geological conditions, such as faulting, seam inclination, block size, seam variation, roof and floor conditions, rock pressure and geo-mechanic conditions (criteria C2); • Mining hazards, such as gas, water, dust ...
    ... spontaneous combustion (criteria C3); • Potential for mechanization, such as seam inclination, seam thickness, floor and roof conditions, block size, coal clearance facilities and supply facilities (criteria C4); • Quality of coal and products, such as coal type, sulphur content, ash content, ...

  • 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
    ... [20], both of which use finite-state technology as initially introduced in [5]. Serbian e-dictionaries of simple forms have reached a considerable size: they have a total of more than 127,000 lemmas [6] generating close to 4.4 million forms. Unitex distri- bution includes a large sample from the Serbian ...
    ... the software tool LeXimir means of appropriate FSTs. Organizing dictionaries in sets of different files is prac- tically motivated. Namely, smaller size files are much easier to manipulate. With LeXimir’s editor for MWUs the user can perform, beside the usual func- tions — add, insert, copy, change ...
    ... 93.42% of correct results (there were no partly correct results). However, when looking at these results, one must also take into account that the size of data sets also varies considerably. Although a comparison with the results obtained in the first evaluation would seem natural, it is not easy to ...

  • Флотабилност халкопирита из полиметаличне руде рудника „Рудник”

    Ђурица Н. Никшић (2022)
    The doctoral dissertation Chalcopyrite flotability from polymetallic "Rudnik" mine ore consists of two parts. The first part is a general part in which the theoretical foundations of the flotation concentration process, the flotation properties of chalcopyrite, the influence of certain flotation reagents and the mechanism of action on the flotation properties of chalcopyrite are presented. This part also describes the process of flotation concentration of polymetallic ore from the "Rudnik" mine. The second part is ...
    Халкопирит, флотацијска концентрација, KAX, NaCN, pH пулпе

  • Concepts for Improving Machine Learning Based Landslide Assessment

    Miloš Marjanović, Mileva Samardžić Petrović, Biljana Abolmasov, Uroš Đurić (2019)
    Katastar klizišta, Podložnost, Hazard, Mašinsko učenje, Uzorkovanje, Validacija

  • Aлтерације перидотита контролисане карактером флуида на примеру харцбургита Рудника - Серпентинизација или талкизација?

    Стефан Петровић, Наталија Батоћанин (2020)
    У раду су приказани резултати испитивања серпентинисаних харцбургита Брђана (43°58'45.1" СГШ, 20°25'12.6" ИГД) и талкизираних харцбургита откривених у интервалу 429-559.8 m у истражној бушотини 330А/18 (44°07'33.2" СГШ, 20°30'28.5" ИГД) на Руднику. Узорци оба локалитета показују карактеристике резидуалних харцбургита из омотача, односно тектонита; лепидобластичне, бластозрнасте, или порфирокластичне структуре и масивне текстуре. Серпентинисани харцбургити и серпентинити Брђана су изграђени од серпентина, ретких реликата оливина и ортопироксена, акцесорног спинела, и веома ретког секундарног магнезита и магнетита. Најдоминантнији састојак (местимично гради и преко ...
    Рудник, Брђани, харцбургити, серпентинити, талк
    ... orthopyroxene are occasional. Relic olivine crystals, in negligible amounts, are beneath 0.1 mm in size. Accessory spinel appears in subhedral, сracked grains of reddish- brown color, up to 1 x 1.2 mm in size. 25 DISCUSSION Serpentinized harzburgites from Brdjani are dominantly ...
    ... be recognized the initial phase of orthopyroxene replacement by talc. Olivine appears in isometric, subhedral to anhedral crystals of different size, maximally about 0.8 x 1.5 mm. Olivine crystals are cracked, penetrated by thin serpentine and magnetite mesh. Rotated grains displaying undulatory ...
    ... of clinopyroxene, diopside/augite (Fig. 7). The latter is low abundant (<5%). Accessory opaque minerals occur in subhedral grains up to 1 x 2 mm in size. Precise determination of identified opaque mineral of cubic symmetry requires further investigations. Serpentinites from Brdjani display massive ...

  • ‘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

  • Postojeće stanje i budući trendovi u preventivnoj zaštiti podzemnih voda Srbije

    Vladimir Živanović (2022)
    Podzemne vode predstavljaju osnovni, a u mnogim zemljama i jedini resurs za javno vodosnabdevanje stanovništva tako da zaštita podzemnih voda predstavlja bitan preduslov za njihovo dugotrajno i održivo korišćenje. Kako u svetu, tako i u Srbiji, zaštita podzemnih voda se najvećim delom svodi na primenu preventivnih mera zaštite. Kod planiranja zaštite većih prostora sve više se koriste metode za ocenu ranjivosti podzemnih voda. Njihova primena je posebno naglašena u karstnim područjima zato što se tu izdvajaju delovi terena sa ...
    Zaštita podzemnih voda, karte ranjivosti podzemnih voda, karta hazarda, karte rizika od kontaminacije, monitoring podzemnih voda, Srbija

  • Approach to operational mine planning: Case study Tamnava West

    Dejan Stevanović, Mirjana Banković, Milica Pešić Georgiadis, Ranka Stanković (2014)
    ... conditions. This is particularly evident when considering the fact that the deposits on which exploitation is carried out are often, small in size, with poor quality and with complex structure and geometry, often in locations that have unfavorable infrastructure, or in regions with significant ...
    ... provide a better structural model, the technique 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 ...
    ... International Journal of Coal Geology, vol. 80, pp. 145-156 6 Beretta F, Costa J, Koppe J, Souza V, 2009, Reducing coal quality variability with size optimization of blending piles, Fourth World Conference on Sampling & Blending, The Southern African Institute of Mining and Metallurgy 7 ...

  • Crystal structure of K3EuSi2O7

    Sabina Kovač, Predrag Dabić, Aleksandar Kremenović (2021)
    alkalni silikati elemenata retkih zemalja, kristalna struktura, sinteza metodom fluksa, rendgenska difrakcija na monokristalu
    ... Bragg-Brentano geometry and Cu Kα radiation. The diffractometer was operated at 40 kV and 30 mA, while the scan range was from 3 to 60° 2θ, with a step size of 0.02° and time per step of 1.25 s. PDXL 2 software18 was used for the powder diffraction data analysis. Scanning electron microscopy (SEM) was ...
    ... resulting material was manually removed from the crucible, washed with distilled water and dried in air. Bow-tie aggregate colorless crystals up to 300 μm size embedded in a polycrystalline matrix were observed. X-ray structure determination Selected elongated prismatic colorless single crystal was fixed ...
    ... 2σ(F2)] 0.035 V / Å3 1239.05 (8) wR(F2) 0.069 Z 6 S 1.13 Radiation type Mo Kα No. of reflections 528 µ / mm−1 9.39 No. of parameters 40 Crystal size, mm 0.27×0.04×0.04 Δρmax; Δρmin / e Å−3 1.01; - 0.69 Table II. Selected geometric parameters for K3EuSi2O7. Symmetry codes are given in footnotes ...

  • Lower Berriasian ammonites from Dedina (Golubac Mountains, eastern Serbia) and their biostratigraphic implication

    Zdenek Vasícek , Dragoman Rabrenović, Petr Skupien, Barbara Radulović (2023)
    Ammonites, Taxonomy, Lower Berriasian, Getic, Northern Tethys, Serbia
    ... moulds and impressions. Only less than one-third of the specimens could be used for determination and a detailed taxonomic elaboration. As far as size parameters are concerned, specimens with shell diameters in the range of 20-—30 mm and a smaller number that within 30—60 mm completely predominate ...
    ... aptychi are determined at the species level. They are shown in Fig. 6. Identification of the studied material is usually difficult by the juvenile size of the specimens, the accompanied planar deforma- tion or lateral deformation, the unknown shape of the ventral side, Z. Vašiček, D. Rabrenović ...
    ... specimens, the diameter of the shell, D, for which the measurement was made to one-tenth of a mm (or Dmax, indicating the maximum preserved shell size), as well as the height of the whorl (H), width of the umbilicus (U), and the ratios of H/D and U/|D are given in paren- theses. The width of the ...