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Упит dcterms_creator_txt:Marija D. Prekajski

984 items

  • Analiza primene višekriterijumskih metoda u optimizaciji izbora hidruličnih bagera na površinskim kopovima uglja

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Filip Miletić, Ivan Janković (2019)
    Hidraulični bageri primenjuju se u različitim oblastima privrede a najzastupljeniji su u građevinarstvu i rudarstvu. Na površinskim kopovima sa kontinualnim sistemima, klasifikuju kao pomoćna mehanizacija a na površinskim kopovima sa diskontinualnim sistemima, kao osnovna mehanizacija. Kako je u oba slučaja njihova primena neizostavna, važno je izvršiti adekvatnu analizu postojećih podataka, u cilju optimizacije izbora tipa hidrauličnog bagera u odnosu na uslove rada datog površinskog kopa. U radu su opisane različite višekriterijumske metode koje su korišćene za analizu hidrauličnih bagera. ...
    višekriterijumske metode, površinski kop uglja, pomoćna mehanizacija, hidraulični bager
    ... shape) 0, ako je 0 ( , ) 1, ako je 0 d P a b d     II Kvazi (U- shape) 0, ako je ( , ) 1, ako je d q P a b d q     III Linearni (V- shape) 0 , ako je ( , ) / , ako je 1 , ako je d q P a b d p q d p d p       IV Nivoski (Level- ...
    ... shape) 0 , ako je ( , ) 1/ 2 , ako je 1 , ako je d q P a b q d p d p       V Linearni sa područjima indiferenci je 0 , ako je ( , ) ( ) / ( ) , ako je 1 , ako je d q P a b d q p q q d p d p         VI Gausov (Gaussian prefferen- ...
    ... (31) 1, 0, ks ks ks ako je c c f ako je c c     1, , 1,2,..., ( 1) m k k s ksd d s n m m      (32) 1, 0, ks ks ks ako je d d g ako je d d     Na osnovu matrice dominacije slaganja i neslaganja, formira se agregatna matrica dominacije ...

  • Clockwise vertical-axis rotation in the West Vardar zone of Serbia: Tectonic implications

    Vesna Lesić, Emo Márton, Violeta Gajić, Dragana Jovanović, Vesna Cvetkov (2018)
    The Vardar-Tethyan mega-suture between the Eurasian and Adria (Gondwana) margins comprises remnants of oceanic lithosphere of Neotethys and distal parts of the adjacent continental margins including unconformable Late Cretaceous sedimentary cover and Cenozoic igneous rocks of post-obduction age. This study provides kinematic constraints for displacements and rotations affecting the Serbian part of the West Vardar and Jadar-Kopaonik units after the closure of the Neotethyan (= Sava) Ocean. The targets of the paleomagnetic research were Late Cretaceous sediments representing an ...
    Paleomagnetism, Clockwise rotation, Dinarides, West Vardar zone
    ... ic d ir ec ti o n s b as ed o n th e re su lt s o f p ri n ci p al co m p o n en t an al y si s (K ir sc h v in k 1 9 8 0 ). K ey : L at . N an d L o n . E : g eo g ra p h ic co o rd in at es (W G S 8 4 ), n /n o : n u m b er o f u se d /c o ll ec te d sa m p le s; D , I (D c , I c ): d ec li ...
    ... sc ep ti b il it y ei th er sc at te re d d ir ec ti o n s o r b ad d em ag n et iz at io n cu rv es . * L ef t o u t fr o m te ct o n ic in te rp re ta ti o n d u e to cl o se n es s to th e d ir ec ti o n o f p re se n t E ar th m ag n et ic fi el d o n th e sa m p li n g ar ea . M ag n et ...
    ... ad in g s fo r th e fi el d o ri en ta ti o n o f th e co re s w er e co rr ec te d u si n g IG R F -1 2 In te rn at io n al G eo m ag n et ic R ef er en ce F ie ld m o d el (T h éb au lt et al . 2 0 1 5 ). T h e ag e d et er m in at io n w as d o n e b y M il en a D u n či ć b as ed o n w ...

  • Determining the Availability of Continuous Systems at Open Pits Applying Fuzzy Logic

    Miljan Gomilanović, Miloš Tanasijević, Saša Stepanović (2022)
    This work presents a model for determining the availability of continuous systems at open pits by applying fuzzy logic and fuzzy inference systems. The applied model was formed by the synthesis of independent partial indicators of availability. The model is based on an expert system for assessing the availability of continuous mining systems. The availability of the system, as a complex state parameter, is decomposed into the partial indicators, reliability, and convenience of maintenance, and the fuzzy compositions, used ...
    системи, континуални систем експоатације, површински коп, рударство, расположивост, фази логика, max–min композиција, min–max композиција

  • Organoselenium functionalized oxacycles as ligands in some trans-palladium(II) complexes: biological evaluation and interaction with small biomolecules

    I. Raković, D. Ćoćić, O. Milošević-Djordjević, I. Radojević, M. N. Živanović, K. Virijević, J. Pavić, J. Tubić Vukajlović, A. Marković, J. S. Marjanović, M. D. Kostić, P. Čanović, A. Mijatović, V. M. Divac (2023)
    In this article, the biological evaluation and interaction of three selenium-based trans-palladium complexes (Pd–Se1, Pd–Se2, and Pd–Se3) with small biomolecules were performed. The UV–Vis kinetic studies on substitution reaction of synthesized complexes with selected biologically important N- and S-bonding ligands (LCys, GSH, L-Met, 50-GMP, L-His) has emphasized greater affinity of sulphur-based ligands for complex-binding, while the general order of the reactivity was L-Cys > GSH > L-Met > 50-GMP > L-His. The complex reactivity toward small biomolecules is influenced ...
    Materials Chemistry, Physical and Theoretical Chemistry

  • Дефинисање механичких својстава алтерисаног стенског материјала лабораторијским методама

    Вељко М. Рупар (2022)
    Основни циљ овог рада је да представи методологију одређивања механичких својстава хетерогеног стенског масива који изграђују дацит (Д) и алтерисани дацит (АД), где је уочена је зона постепеног преласка од алтерисаног дацита до дацита. Механичка својства стенског масива у тој зони утврђена су на основу лабораторијских испитивања једноосне и троосне чврстоће на притисак стенског материјала композитних узорака. Композитни узорци су се састојали од дискова стенског материјала, при чему је висина дискова h дефинисала различити процентуални удео појединог стенског материјала, ...
    дацит, алтерисани дацит, једноосна чврстоћа на притисак, троосна чврстоћа на притисак, композитни узорци, механика стена, стабилност косина

  • 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

  • Asbestos-Based Pottery from Corsica: The First Fiber-Reinforced Ceramic Matrix Composite

    Philippe Colomban, Aleksandar Kremenović (2020)
    Asbestos-containing pottery shards collected in the northeast of Corsica (Cap Corse) and dating from the 19th century, or earlier, have been analyzed by SEM-EDS, XRPD, FTIR and Raman microspectroscopy. Blue (crocidolite) and white (chrysotile) asbestos fiber bundles are observed in cross-sections. Most of the asbestos is partly or totally dehydroxylated, and some transformation to forsterite is observed to occur, indicative of a firing above 800 C. Examination of freshly fractured pieces shows a nonbrittle fracture with fiber pull-out, consistent with ...
    asbestos, CMC, Corsica, fiber, pottery
    ... 3400 3575 ___ ——— s ___ _— d) |--7" - — 3740 d)) c |-- ——· —— — I r — TTAA K_ s Fi 3670 -i 3220 3400 3555 8, 5 _ -. ——\ b) 3 —— \ <| _ — c) WJE — Y | ___ \ 3) T T T T ı 3000 3250 3500 3750 4000 Wavenumber / cm" Figure 4. FTIR ATR spectra of samples (a-d) (see Figure 1) in the O-H/H»O ...
    ... are found in samples a, b and d, while albite is found only in samples a and b. Crocidolite is found in samples b and d, while tremolite is found in samples b and c. Diopside and orthopyroxene are found in samples b and c, while talc is found in samples c and d. Minor abundant mineral phases noticed ...
    ... [13]. Figures 3 and 4 show representative FTIR ATR spectra collected on powdered fragments of the shards. Spectrum d/ has been recorded on a fiber bundle extracted from sample d. The bands, for instance, the Si-O stretching, and bending, modes at ~960 (1015 and 1080) and 620 cm-! (Figure 3), ...

  • Polyhedral characteristics of the cosalite-type crystal structures

    Sabina Kovač, Predrag Dabić, Aleksandar Kremenović, Aleksandar Pačevski, Ljiljana Karanović, Marko V. Rodić, Martina Tribus (2019)
    kristalna struktura, kozalit, poliedarske karakteristike

  • Tektono-termalna evolucija kontakta Dinarida i Karpato-Balkanida u području Jastrepca

    Dalibor Erak (2019)
    Predmet istraživanja doktorske disertacije je tektonska evolucija područja planine Jastrebac u centralnoj Srbiji, gde višefazna tektonska aktivnost od mezozoika do danas komplikuje rekonstrukciju strukturnih odnosa i geološke evolucije ovog prostora. Kompleksna višefazna evolucija planine Jastrebac u Srbiji je demonstrirana kombinovanjem kinematskih podataka prikupljenih na terenu i mikrostrukturnih opservacija sa dodatnim termohronološkim podacima “fission track” i podacima odredbe starosti metodom U-Pb na cirkonima. Gornjokredna ekshumacija bila je praćena gornjokredno-eocenskim navlačenjem i magmatizmom vezanim za kontinentalnu koliziju, pri čemu je akreciona ...
    kinematika, termohronologija, ekstenzioni detačmenti, Dinaridi, Karpato-Balkanidi
    ... International Journal of Earth Sciences 100, 1181-1206. Schefer, S., Egli, D., Missoni, S., Bernoulli, D., Gawlick, H.-J., Jovanović, D., Krystyn, L., Lein, R., Schmid, S.M., Sudar, M., 2010. Triassic sediments in the D. Erak: Tektono-termalna evolucija kontakta Dinarida i Karpato-balkanida u području ...
    ... Matenco, L., Radivojević, D., 2012. On the formation and evolution of the Pannonian Basin: Constraints derived from the structure of the junction area between the Carpathians and Dinarides. Tectonics 31, TC6007, doi: 10.1029/2012tc003206. Meinhold, G., Kostopoulos, D., Frei, D., Himmerkus, F., Reischmann ...
    ... digitalizovana D. Erak: Tektono-termalna evolucija kontakta Dinarida i Karpato-balkanida u području Jastrepca 11 geološka karta šireg područja planine Jastrebac, koja je inovirana na bazi informacija prikupljenih tokom izvedenih terensko-kabinetskih istraživanja (Prilog 1). D. Erak: Tektono-termalna ...

  • Ostvarivanje dobiti pri uvođenju sistema agregatnih zamena na osnovnoj rudarskoj mehanizaciji površinskih kopova EPS

    Predrag Jovančić, Ignjatović Dragan, Đenadić Stevan (2021)
    Jedan od osnovnih zadataka na površinskim kopovima uglja je ostvarivanje zadovoljavajućeg vremenskog i kapacitetnog iskorišćenja kontinualnih sistema. Da bi se to postiglo, neophodno je izvršiti izmene u postojećoj strategiji održavanja. Preduslov je uvođenje agregatne zamene vitalnih delova na rudarskim mašinama. Benefiti su višestruki. Očekivani rezultati ovakvog pristupa su: smanjenje zastoja i povećanje vremena rada; direktne materijalne uštede; bolja organizacija rada; racionalizaciju radioničkih i magacinskih kapaciteta; povećanje vrednosti mašina. Da bi se uvela agregatna zamena neophodne su investicije za nabavku ...
    agregatne zamene, održavanje, mehanizacija, Benefit Cost analiza

  • 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
    ... white rectangle. Cretaceous Research 151 (2023) 105623 Z. Vašiček, D. Rabrenović, P. Skupien et al. STIOJMOU NO|HJHOLUQTIS| snuo/ide|Jeuie|e|}huoy\ —*- snjouip s n u o / g d e y u n d ) 2 u l ) snjejound s n u o / Q d e ) o u n c OjSIJeoqns BiJejeJe5o} — esueuo/(ouq seje2oouanojsqns ...
    ... such 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 ...
    ... qns ___ee- snjejnojossj sojtuejdqnsopnescj —___e- IJouoj s e j u u e J j d q n s o p n o s c e e e — - Jedse '}o SeJeO!SOqJE}/ • uunojojd '} SeJaolJeJ5aN • s n o n u o d ·}o s e j i u p / d q n s o p n e s c ___ __e-– _ – I I uunujuu SeJeoiJeuBeN- 'ds sejiue/u00g ...

  • 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)
    ... 103283. Nytoft, H.P., Kildahl-Andersen, G., Lindström, S., Rise, F., Bechtel, A., Mitrović, D., Đoković, N., Životić, D., Stojanović, K., 2019. Organic Geochemistry 129, 14–23. Stojanović, K., Životić, D., 2013. International Journal of Coal Geology 107, 3–23. ...
    ... Lusatia I. Kojic, J. Kus, D. Zivotic, K. Stojanovic Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] 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 ...
    ... France THE POTENTIAL OF BIOMARKERS TO 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 ...

  • Application of Peleg model on mass transfer kinetics during osmotic dehydratation of pear cubes in sucrose solution

    Vesna Pavelkić, Tanja Brdarić, Marija Petrović, Gavrilo Šekularac, Milica Košević, Lato Pezo, Marija Ilić (2015)
    The applicability of Peleg model was investigated for predicting mass transfer kinetics during the osmotic dehydration (OD) process of pears, at different concentrations (40, 60 and 70%, w/w) and temperatures (20, 35 and 50 °C) of sucrose solution. Increase in sucrose solution concentration resulted in higher water loss (WL) and solid gain (SG) values through the osmotic treatment period. After 360 min of osmotic treatment of pears, WL ranged from 23.71 to 31.68% at 20 °C, from 24.80 to ...
    осмотска дехидрација, крушкa, кинетика, температурни ефекат, Пелег модел

  • Uniaxial compressive strength test before and after standard fire test on rock mass

    Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović (2022)
    ... Marija Krstićc, Aleksandar Erićd, Radovan Gospavića , Snežana Ilićc , Aleksandar Kijanovićc a Faculty of Civil Engineering, University of Belgrade, Serbia b Faculty of Mining and Geology, University of Belgrade, Serbia c Institute for testing materials IMS, Belgrade, Serbia d Unogradnja ...
    ... test before and after standard fire test on rock mass Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović Дигитални репозиторијум Рударско-геолошког факултета Универзитета ...
    ... test before and after standard fire test on rock mass | Stefan Mitrović, Goran Todorović, Bojan Kostić, Milica Mirković-Marjanović, Nikola Božović, Marija Krstić, Aleksandar Erić, Radovan Gospavić, Snežana Ilić, Aleksandar Kijanović | Fifth symposium of the Macedonian Association for Geotechnics, Ohrid ...

  • The effect of finite driving rate on avalanche distributions

    Sonja Radić, Sanja Janićević, Dragutin Jovković, Đorđe Spasojević (2021)
    Statistics, Probability and Uncertainty,Statistics and Probability,Statistical and Nonlinear Physics

  • Hyperpycnites within the Devonian-Carboniferous flysch of the Carpatho-Balkanides (Kostadinovica, eastern Serbia)

    Miloš Radonjić (2020)
    This study presents new discoveries of vascular plants and the trace fossil Dictyodora liebeana (GEINITZ) from the Devonian–Carboniferous Kučaj-Zvonce flysch of the Carpatho-Balkanides and the implications of this fossil association for its sedimentary setting. The occurrence of the described plant debris in a deep-marine environment indicates the presence of hyperpycnites within the siliciclastic turbidites exposed at the Kostadinovica locality. The sedimentological data and the characteristics of the fossil material support the proposed model in which the sediment was at ...
    Mississippian flora, Dictyodora liebeana (GEINITZ), hyperpycnites, Kučaj-Zvonce flysch, Carpatho-Balkanides
    ... the next 4 m of unit C. 3.4. Unit D (interval: 25.25 to 31.75 m of the column) Unit D begins at 25.25 m from the start of the column and is 6.5 m thick. Turbidite beds composed of medium-grained sandstones and siltstone/mudstones are the dominant members of unit D (Fig. 7a). Their characteristics ...
    ... hummocky-type to unidirectionally inclined lamina- Figure 7. Sedimentary characteristics of unit D. (a) The transition from unit C into unit D. The change is noticeable in the onset of fining-upward sequences (unit D) compared to sandstone/siltstone repetition (unit C). A gradual change of colour also marks ...
    ... onset of unit D is marked by a sharp change in facies association compared to unit C. Aside from the general similari- ties described above, differences within units A and D are most notably the rare occurrence of S3 facies (fine-grained sandstones with climbing ripples) within unit D. In terms of ...

  • 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
    ... 2. Polomčić, D., Bajić, D., Ristić-Vakanjac, V., Čokorilo, M., Drašković, D., Špadijer, S., Hydrodynamic Characteristics of the Water Supply Source „Peštan“ (Lazarevac, Serbia), Vodoprivreda, 261-263, Serbian Irrigation and Drainage Society, Belgrade, pp 55-68, 2013. 3. Đurić, D., Lukić, V., ...
    ... Technology Ltd., Sofia, Bulgaria, pp 599-606, 2011, http://dx.doi.org/10.5593/sgem2011/s02.136 7. Polomčić, D., Stevanović, Z., Dokmanović, P., Ristić-Vakanjac, V., Hajdin, D., Milanović, S., Bajić, D., Optimization of Groundwater Supply in Serbia, Proceedings of http://dx.doi.org/10.1007/s10040-013-1025-9 ...
    ... Pušić, M., Vidović, D., Đurić, D., Boreli-Zdravković, Đ., Pollution Transport analysis in defining the Sanitary Protection Zones of Groundwater Sources in Alluvial Areas, Vodoprivreda, 264-266, Serbian Irrigation and Drainage Society, Belgrade, pp 203-218, 2013. 12. Pollock, D. W., User's Guide ...

  • Osnovi hidrogeologije

    Petar Dokmanović (2021)
    hidrogeologija, atmosferska voda, površinske vode, podzemne vode, vodni bilans, poroznost stena
    ... odnosno, δ18O, za teški kiseonik-18, preko sledećih odnosa: ( )    −       δ = ⋅       1 1 uzorka vsmow 1 vsmow D D H H D ‰ 1000 D H (16.4.6.1) ( )     −       δ = ⋅       18 18 16 16 18 ...
    ... radova i odvodnjavanja poljoprivrednog zemljišta. 10 O s n o v i h i d r o g e o l o g i j e I DEO U V O D 11 O s n o v i h i d r o g e o l o g i j e 1.POJAM, PREDMET IZUČAVANJA I PRAKTIČNI ZNAČAJ HIDR ...
    ... poroznosti vrši se na osnovu gustine čvrstih čestica i gustine stena: n s d s = −ρ ρ ρ (6.7.2) 51 O s n o v i h i d r o g e o l o g i j e odnosno (iskazano u procentima): n 1 100%d s = − ⋅       ρ ρ (6.7 ...

  • Development of integrated fuzzy model for mine management optimization

    Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić (2023)
    fuzzy logika, višekriterijumsko odlučivanje, ocenjivanje eksperata
    ... triangular fuzzy number, the fuzzy synthetic extent is calculated using; the following; equation: m i n m -1 m m m 1 1 1 S -Ž MLe|.2.MA, |Ž,D-> 552 d|| _—R — L — j=1 i=1 j=1 jel jcl je1 Mdj XOsj M i=l i=l i=1 Step 3. The degree of possibility of two triangular fuzzy numbers is deter- mined ...
    ... its application to pproximate reasoning,, Information sciences, 8, 199—249. Š| CHANG D. Y. (1996) Applications of the extent analysis method on fuzzy AHP, Rur. J. Oper. Res., 95, 649 655. “} ZnU K., Y. JING, D. CHANG (1999) A discussion on extent analysis method and applications of fuzzy AHP, Eur ...
    ... Fuzzy Logic in Data Mining Process. In: Bai Y., Zhuang H., Wang D. (eds), Advanced Fuzzy Logic Technologies in Industrial Ap- ications, Advances in Industrial Control, London, Springer, DOT: 10.1007,978-1- 84628-469-4 _17. BAJIĆ S., D. BAJIĆ, B. GLUŠČEVIĆ, V. RISTIĆ VAKANJAC (2020) Application of ...

  • Хазард од клизишта у Србији у 21. веку

    Biljana Abolmasov (2019)
    клизишта, хазард од клизишта, промене климе
    ... n.www.unisdr.org [4] Cruden D. M.,Varnes D. J. (1996). Landslide types and processes. I Shuster L. R. (Eds). Landslides, investigations and Mitigation. S Transportation Research Board, National Research Council, Nation Press, Washington D.C. 36�75. [5] Cruden D., D. F. VanDine (2013). Classification ...
    ... http://edition.www.unisdr.org Cruden D. M.,Varnes D. J. (1996). Landslide types and processes. Shuster L. R. (Eds). Landslides, investigations and Mitigation. | Transportation Research Board, National Research Council, Natior Press, Washington D.C. 36 75. Cruden D., D. F. VanDine (2013). Classification ...
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