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Упит dcterms_creator_txt:Panaitescu C.

775 items

  • Nelinearno dinamičko modelovanje potresa izazvanih promenom naponskog stanja pri izradi horizontalnih podzemnih prostorija

    Srđan D. Kostić (2013-11-04)
    U ovoj disertaciji, cilj istraživanja bio je određivanje dinamičkih svojstava potresaizazvanih promenom naponskog stanja pri izradi horizontalnih podzemnih prostorija.Analiza potresa izvedena je sa dva aspekta – u prvom delu istraživanja izučavane suvremenske serije oscilovanja tla za vreme potresa, a u drugom delu vršena je analizastabilnosti fenomenološkog Baridž-Knopof modela bloka sa oprugom. Vremenske serijeoscilovanja tla proučavane su primenom postupka analize surogat podataka, kao ikorišćenjem metoda analize nelinearnih vremenskih serija (primena teoreme orazvijanju skalarne vremenske serije). Analiza vremenskih serija izvedena je ...
    potres, naponsko stanje, podzemne prostorije, bifurkacije, vremenskaserija, deterministički haos, stohastičnost, perturbacije, vremensko kašnjenje, jačina trenja
    ... jednačine u sistemu (7.8) dobija se da je: 2 2 1 1 2 1 2 1 3( ) 0 c c c c c c U U                (7.10) odakle sledi: 2 2 1 1 1 2 2 1 1 1 2 2 2 1 1 2 1 3 1 3 c c c c c c c c c c U U c c U U                             ...
    ... usvojimo da je k1=k2=k, dobijamo: ( ) ( ) c 1 1 12 1 c 1 c 2 2 21 2 c 2 c 0 U U U t c 0 U U U t                     (7.8) Sabiranjem dve jednačine u sistemu (7.8) dobijamo: 1 1 2 2 1 2 1 2 ( ) 2 c c c c c c U U t                  ...
    ...  (7.11) 140   Zamenjujući (7.11) u (7.9) dobijamo izraz za ravnotežno stanje sistema (7.7): c c e 1 1 2 2 1 c c 1 2 c c e 2 2 1 1 2 c c 2 1 c c2 1 U t 3 3 c c2 1 U t 3 3                                 (7.12) U ovom slučaju, analiza ...

  • Nelinearno dinamičko modelovanje potresa izazvanih promenom naponskog stanja pri izradi horizontalnih podzemnih prostorija

    Srđan D. Kostić (2013-11-04)
    U ovoj disertaciji, cilj istraživanja bio je određivanje dinamičkih svojstava potresaizazvanih promenom naponskog stanja pri izradi horizontalnih podzemnih prostorija.Analiza potresa izvedena je sa dva aspekta – u prvom delu istraživanja izučavane suvremenske serije oscilovanja tla za vreme potresa, a u drugom delu vršena je analizastabilnosti fenomenološkog Baridž-Knopof modela bloka sa oprugom. Vremenske serijeoscilovanja tla proučavane su primenom postupka analize surogat podataka, kao ikorišćenjem metoda analize nelinearnih vremenskih serija (primena teoreme orazvijanju skalarne vremenske serije). Analiza vremenskih serija izvedena je ...
    potres, naponsko stanje, podzemne prostorije, bifurkacije, vremenskaserija, deterministički haos, stohastičnost, perturbacije, vremensko kašnjenje, jačina trenja
    ... jednačine u sistemu (7.8) dobija se da je: 2 2 1 1 2 1 2 1 3( ) 0 c c c c c c U U                (7.10) odakle sledi: 2 2 1 1 1 2 2 1 1 1 2 2 2 1 1 2 1 3 1 3 c c c c c c c c c c U U c c U U                             ...
    ... usvojimo da je k1=k2=k, dobijamo: ( ) ( ) c 1 1 12 1 c 1 c 2 2 21 2 c 2 c 0 U U U t c 0 U U U t                     (7.8) Sabiranjem dve jednačine u sistemu (7.8) dobijamo: 1 1 2 2 1 2 1 2 ( ) 2 c c c c c c U U t                  ...
    ...  (7.11) 140   Zamenjujući (7.11) u (7.9) dobijamo izraz za ravnotežno stanje sistema (7.7): c c e 1 1 2 2 1 c c 1 2 c c e 2 2 1 1 2 c c 2 1 c c2 1 U t 3 3 c c2 1 U t 3 3                                 (7.12) U ovom slučaju, analiza ...

  • Influence of Post-Synthesis Treatments on the Properties of Brushite/Monetite Powders

    Željko Radovanović, Lidija Radovanović, Aleksandar Kremenović, Đorđe Janaćković, Rada Petrović (2022)
    Dicalcium phosphate (DP) materials, of which brushite and monetite were the most known, have been intensively studied for several decades because of excellent resorptive and osteoconductive properties that can satisfy the requirements needed for various medical applications, such as bone cements, coatings of metallic implants and bone grafts ...

  • Hydrothermal Synthesized and Alkaline Activated Carbons Prepared from Glucose and Fructose—Detailed Characterization and Testing in Heavy Metals and Methylene Blue Removal

    Sanja Krstić, Milan Kragović, Maja Pagnacco, Vladimir Dodevski, Branka Kaluđerović, Miloš Momčilović, Ivica Ristović, Marija Stojmenović (2018)
    glukoza, fruktoza, аktivni ugalj, hidrotermalni tretman, aktivacija hidroksida, teški metali, metilen plavo
    ... of metamaterials and their achievements in wireless power transfer. J. Mater. Chem. C 2018, 6, 2925–2943. [CrossRef] 29. Li, Y.; Zhou, B.; Zheng, G.; Liu, X.; Li, T.; Yan, C.; Cheng, C.; Dai, K.; Liu, C.; Shena, C.; et al. Continuously prepared highly conductive and stretchable SWNTs/MWNTs synergistically ...
    ... G.; Liu, C.; Shen, C.; Yan, X.; Guob, J.; Guo, Z. Organic vapor sensing behaviors of conductive thermoplastic polyurethane-graphene nanocomposites. J. Mater. Chem. C 2016, 4, 4459–4469. [CrossRef] 32. Liu, H.; Dong, M.; Huang, W.; Gao, J.; Dai, K.; Guo, J.; Zheng, G.; Liu, C.; Shen, C.; Guo, Z. ...
    ... J. Mater. Chem. C 2017, 5, 73–83. [CrossRef] 33. Liu, H.; Li, Y.; Dai, K.; Zheng, G.; Liu, C.; Shen, C.; Yan, X.; Guo, J.; Guo, Z. Electrically conductive thermoplastic elastomer nanocomposites at ultralow graphene loading levels for strain sensor applications. J. Mater. Chem. C 2016, 4, 157–166 ...

  • Rock slope stability analysis under Hoek–Brown failure criterion with different flow rules

    Svetlana Melentijević, Zoran Berisavljević, Dušan Berisavljević, Claudio Olalla Marañón (2024)
    The stability analysis of homogeneous rock slope following the Hoek–Brown failure criterion under the hypothesis of different flow rules is performed based on limit equilibrium and finite element methods. The applied failure criterion is the generalized Hoek–Brown that can be introduced as a shear/normal function in analysis applying different flow rules. The results are compared with those obtained by the application of equivalent shear strength parameters of the Mohr–Coulomb criterion, considering that this is still the most widely used ...
    Kružna klizna površ, Huk-Braunov kriterijum loma, Kriterijum popuštanja, Smičuća/normalna funkcija, Nivo napona, Verovatnoća i parametarska analiza

  • Definition of groundwater genesis and circulation conditions of the complex hydrogeological karst system Mlava–Belosavac–Belosavac-2 (eastern Serbia)

    Ljiljana Vasić, Saša Milanović, Zoran Stevanović, Laszlo Palcsu (2020)
    Geochemistry and Petrology

  • Implementation of alternative forecasting hydrodynamic during designing of mines defense system against groundwater on opencast mine field C example

    Polomčić Dušan, Bajić Dragoljub, Ilić Zoran (2014)

  • A hybrid model for forecasting groundwater levels based on fuzzy C-mean clustering and singular spectrum analysis

    Polomčić Dušan, Gligorić Zoran, Bajić Dragoljub, Cvijović Čedomir (2017)

  • Synthesis and characterization of high-pressure and high-temperature sphene (CaTiSiO5)

    Jelena Pantić, Vladimir Urbanovich, Vesna Poharc-Logar, Bojan Jokić, Marija Stojmenović, Aleksandar Kremenović, Branko Matović (2014)
    Sphene (CaTiSiO5), a calcium titanosilicate ceramic has been prepared from a powder mixture of CaCO3, TiO2 and SiO2 using vibro-milling for homogenization and activation of precursors. During the highpressure and high-temperature synthesis (HPS) process at 4 GPa and 1,200 °C, sphene undergoes into phase transition, from room-temperature phase P21/a to high-temperature phase A2/a. Evidence of that structural phase transition is given in this paper using infrared, Raman spectroscopy and X-ray powder diffraction. Rietveld refinement was employed to get the ...
    Sphene, Phase transition, Raman spectroscopy, X-ray diffraction, SEM, IR

  • Strukture kristala - odabrana poglavlja iz kristalografije i njena multidisciplinarnost

    Ljiljana Karanović (2024)
    Kristalografija

  • Application of geophysical and multispectral imagery data for predictive mapping of a complex geo-tectonic unit: a case study of the East Vardar Ophiolite Zone, North-Macedonia

    Filip Arnaut, Dragana Đurić, Uroš Đurić, Mileva Samardžić-Petrović, Igor Peshevski (2024)
    General Earth and Planetary Sciences
    ... (balanced 64-36%) - Dataset C (balanced 50-50%) Machine learning modelling \ • RF(number of trees 50...250 in 50 increments) - DatasetA Mo de ll in g an d ev al ua ti on - Dataset B - Dataset C • Model evaluation - Unbalanced (A) or balanced (B or C) dataset - Number of trees ...
    ... DatasetA; • DatasetB; • DatasetC with dataset C exhibiting higher values and dataset A exhibiting lower values. The true positive (TP) rate of the ophiolite class indicates that dataset C exhibits the highest rates, while conversely, the dataset C category displays the lowest rates of the true ...
    ... three RF model groups is dataset C, as supported by the analysis of the evaluation metrics. The dataset denoted as C exhibits many ophiolite classifica- tions in the NW sector of the EVZ. However, a noteworthy advantage of a fully balanced dataset is that the RF C models can accurately predict ...

  • Size–strain line-broadening analysis of anatase/brookite (TiO<sub>2</sub>)-based nanocomposites with carbon (C): XRPD and Raman spectroscopic analysis

    Aleksandar Kremenović, Mirjana Grujić-Brojčin, Nataša Tomić, Vladimir Lazović, Danica Bajuk-Bogdanović, Jugoslav Krstić, Maja Šćepanović (2022)
    A size-strain line-broadening analysis of the XRPD patterns and Raman spectra for two anatase/brookite (TiO2)-based nanocomposites with carbon (C) was carried out and the results compared with those of a similar sample free of carbon. The crystal structures and microstructures of anatase and brookite, as well as their relative abundance ratio, have been refined from XRPD data by the Rietveld method (the low amount of carbon is neglected). The XRPD size-strain analysis resulted in reliable structure and microstructure results ...
    Materials Chemistry, Metals and Alloys, Atomic and Molecular Physics, Optics, Electronic, Optical and Magnetic Materials

  • Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic

    Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković (2020)
    Artificial lift methods have applications in oil wells where oil production is no longer possible due to natural reservoir energy, so this necessary energy is added by introducing lift methods. In order to achieve optimum production, the selection of an artificial lift method is very important. This paper uses fuzzy logic as a mathematical and conceptual model for selection of the optimal artificial lift method. The outcome or IF-THEN rules, as the central part of the model, is based ...
    mehaničke metode, proizvodnja nafte, fazi logika, donošenje odluka, optimizacija
    ... B6 in B, and C1 to C5 in C. At the second level of synthesis, A, B and C parameters are synthesized into the M (Figure 4).Energies 2020, 13, x 9 of 15 Figure 4. Hierarchical structure of fuzzy composition. Partial indicators of optimal method of selection, A, B and C, are presented as membership ...
    ... Maximum operating volume (m3/d) 1069 7124 2672 5343 801 Typical operating temperature (°C) 38–177 38–135 38–121 38–121 24–66 Figure 1. The schematic diagram of the fuzzy model. Parameters (B and C) are exact data and are measurable, while (A) parameters can be presented according to the experience ...
    ... 18–5343 53–712 18–1781 0.89–392 Maximum operating volume (m3/d) 1069 7124 2672 5343 801 Typical operating temperature (◦C) 38–177 38–135 38–121 38–121 24–66 Maximum operating temperature (◦C) 288 204 260 204 121 Corrosion handling Good to Excellent Good Excellent Good to excellent Fair Gas handling Fair ...

  • Using Lexical Resources for Irony and Sarcasm Classification

    Miljana Mladenović, Cvetana Krstev, Jelena Mitrović, Ranka Stanković (2017)
    The paper presents a language dependent model for classification of statements into ironic and non-ironic. The model uses various language resources: morphological dictionaries, sentiment lexicon, lexicon of markers and a WordNet based ontology. This approach uses various features: antonymous pairs obtained using the reasoning rules over the Serbian WordNet ontology (R), antonymous pairs in which one member has positive sentiment polarity (PPR), polarity of positive sentiment words (PSP), ordered sequence of sentiment tags (OSA), Part-of-Speech tags of words (POS) ...
    ... ?b) (?b near_antonym: ?c) -> (?a swn:irony ?c)]" "[rule2: (?a swn:similar_to ?b) (?b near_antonym: ?c) -> (?a swn:irony ?c)]" "[rule3: (?a swn:also_see ?b) (?b near_antonym: ?c) -> (?a swn:irony ?c)]" "[rule4: (?a swn:verb_group ?b) (?b near_antonym: ?c) -> (?a swn:irony ?c)]" 8Total number of synsets ...
    ... to ?c) (?c near_antonym:?d)->(?a swn:irony ?d)]" "[rule31: (?a swn:synonym ?b)(?b swn:also_see ?c) (?c near_antonym:?d)->(?a swn:irony ?d)]" "[rule41: (?a swn:synonym ?b)(?b swn:verb_group ?c) (?c near_antonym:?d)->(?a swn:irony ?d)]" "[rule51: (?a swn:synonym ?b)(?b swn:bee_in_state ?c) (?c near_antonym: ...
    ... converting OWL rules into the Jena rules format. "[rule5: (?a swn:bee_in_state ?b) (?b near_antonym: ?c) -> (?a swn:irony ?c)]" "[rule6: (?a swn:hyponym ?b) (?b near_antonym: ?c) -> (?a swn:irony ?c)]" If we look at the rules from the set {rule2, . . . , rule6}, it can be noticed that each rule can ...

  • Multi - Attribute Technological Modeling of Coal Deposits Based on the Fuzzy TOPSIS and C - mean Clustering Algorithms

    Gligorić Miloš, Gligorić Zoran, Beljić Čedomir, Torbica Slavko, Štrbac-Savić Svetlana, Nedeljković Jasmina (2016)

  • 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
    ... µS(n)). (9) (ii) The membership functions can form C= n3 combinations among themselves. Each combination Ac represents practically one possible assessment Ai(8). Ac = [ µR( j=1, ..., n),µM( j=1, ..., n),µS( j=1, ..., n) ] , (10) for each c = 1 to C. (iii) If only values that satisfy the condition ...
    ... where O ≤ C). Each outcome has the corresponding values (iv) and (v) that further identify it for the estimate. (iv) Below, for each combination c that satisfies the condition of the outcome, the Jc value is calculated and rounded as an integer, in the following way: Jc = [( wRi · j(µR)c ) + ( ...
    ... the results are shown in Tables 4 and 5. Table 4. Results of questionnaire for new machines. Analyst B1-N B2-N B3-N ‘A’ ‘B’ ‘C’ ‘D’ ‘E’ ‘A’ ‘B’ ‘C’ ‘D’ ‘E’ ‘A’ ‘B’ ‘C’ ‘D’ ‘E’ 1. R 0.7 0.3 0.8 0.2 0.6 0.4 M 0.4 0.6 0.7 0.3 0.5 0.5 S 0.3 0.7 0.6 0.4 0.6 0.4 2. R 0.6 0.4 0.6 0.4 0.3 0.7 M 0.6 0 ...

  • Curcumin nanonization using an alternative small-scale production unit: selection of proper stabilizer applying basic physicochemical consideration and biological activity assessment of nanocrystals

    Ines Nikolić, Jelena Antić-Stanković, Dragana Božić, Danijela Ranđelović, Bojan Marković, Dominique Jasmin Lunter, Aleksandar Kremenović, Miroslav Savić, Snežana Savić (2020)
    As the number of poorly soluble drugs is increasing, nanocrystals have become very interesting due to wide range of application possibilities. Curcumin was used as a model active ingredient in this work. Even though it has many proven positive effects, due to its physicochemical issues, its possibilities have not been fully exploited. The goal of this work was to select optimal conditions for a top-down method for curcumin nanosuspension production, and to perform their comprehensive characterization applying complementary methodologies: ...
    nanocrystal, curcumin, top-down method, wetball milling

  • Geotermalni potencijal pliocensko-kvartarnih sedimenata na teritoriji opštine Zemun

    Matija Zorić (2024)
    Grad Beograd se nalazi na području koje je izuzetno bogato podzemnim vodama i hidrogeotermalnim resursima. Najveće količine podzemnih voda akumulirane su u okviru aluvijalnih peskovito-šljunkovitih sedimenata i krečnjaka tortonsko-sarmatske starosti. Opština Zemun ima najveći geotermalni potencijal od svih Beogradskih opština, čak 57.7% od ukupnog potencijala celog grada Beograda. Master rad je fokusiran na istraživanju i analizi poznatih tehničkih sistema, kao i termotehničkih sistema koji su u upotrebi na teritoriji opštine Zemun. Tehnički sistemi se odnose na istražno-eksploatacione bunare koji nemaju ...
    geotermalna energija, kvartarni sedimenti, pliocenski sedimenti, teritorija opštine Zemun
    ... godišnja temperatura vazduha u Zemunu iznosi 12.5 "C, dok se prosečne temperature vazduha i padavine u Zemunu mopgu videti na slici 4. 40 "C 100 mm _—__–~ – – 30"%C 30"C ~ ~ 30 "C 75 mm 20 *C 10 *C 50 mm O?C 25 mm -10 "C -20 *C omm | Padavine — Prosečni dnevni maksimum — · ...
    ... resurse niske entalpije (temperatura fluida ispod 100 "C), zbog čega Je došlo do detaljnije podele ovih resursa (Milenić, Vranješ 2015): • sub(hidro)geotermalna energija ( < 30 *C ) • (hidro)geotermalna energija u užem smislu ( 30 "C - 100 ?*C ) Hidrogeotermalna energija se pri nižim temperaturama ...
    ... _ _ _ _ __ _B A/ \E IĆ } |_ _ _ _ _ _ _ _ _ B : G C E C| L ı a —— — Po lj op ri vr ed ni fa k. A a u — — Ba ta jn ic a 1 |_ __ __ __ __ __ Kl :F ic iu a{ {e -y % | _ _ _ _ _ _ _ _ _ _ B : F \ c C i u { e : k ) z ı a — — Ba nk a bi lj ni h ...

  • Bilingual lexical extraction based on word alignment for improving corpus search

    Jelena Andonovski, Branislava Šandrih, Olivera Kitanović (2019)
    Library and Information Sciences,Computer Science Applications

  • Analiza primenjenih metoda za transport parafinske nafte

    Dunja Milojević (2024)
    Sadržaj parafina u nafti ima dominantan uticaj na svojstva parafinskih nafti. Taloženje parafina, odnosno taloženje čvrstih čestica parafinskog voska, predstavlja ozbiljan globalni problem tokom proizvodnje i transporta sirove nafte. Samo taloženje voska zavisi od termodinamičkih faktora, poput temperature, pritiska i sastava nafte. Transport nafte cevovodima je uobičajeni proces transporta u naftnoj industriji. Kada prilikom cevovodnog transporta parafinske sirove nafte, dođe do prekida protoka i hlađenja nafte ispod temperature stinjavanja, parafini će kristalisati, pri čemu će doći do, geliranja celokupne transportovane ...
    nafta, parafinski vosak, taloženje, transport, naftovod
    ... bar ı ambijentalna temperatura 15 "C), alkani sa manje od 5 atoma ugljenika se nalaze u gasovitom stanju ( metan -– CHx, etan - C,He . propan - CaHg , butan - C,MHyo ), alkani sa 5 do 15 atoma ugljenika se nalaze u tečnom stanju ( pentan -CsHy> ; penta-dekan C,5sHy>), a alkani koji imaju preko ...
    ... Najniža temperatura na dubini ukopavanja naftovoda je 18%C. Neobrađena nafta ima na 18%C prividni viskozitet 0,60 Pas, dok obrađena nafte ima prividni viskozitet 0,1 Pas. Nafta se u postupku obrade zagreva do 90-95"C i hladi brzinom 0,6 "C/min, do temperature od 189C. (Prstojević, Cevovodni transport ...
    ... alkan koji je pri normalnim uslovima u čvrstom stanju je n- heksa-dekan (C,,Hya- tačka topljenja 18%C ). (Prstojević, Priprema nafte, gasa i ležišnih voda, 2012) Većina parafina pronađenih u naftama nalazi se u rasponu od C,yg — Ces (Stubsjgen, 2013, str. 19) Tačka ključanja parafinskih ugljovodonika ...