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Упит dcterms_subject_txt:space group

367 items

  • Design of a sucker rod pumping system

    Ana Ponoćko (2024)
    For a long time in the history of oil production, sucker rod pumps have been the first and in many cases the only choice when it comes to mechanical extraction methods. Proper selection of each individual element of the system enables optimization, which entails benefits in the form of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The ...
    sucker rod pump, fluid production, mechanical extraction methods,, Prosper, QROD, RODSTAR
    ... — Rp- inlet pressure, or the pressure below the pump (bar) — V5l - velocity of liquid flow through the annular space of the anchor reduced to the full cross-section of the annular space of the anchor without gas (m/s) 3.3 Sucker Rods Sucker rods are manufactured from high-quality steel with a ...
    ... standing valve lifts off the standing, valve. At this point, the fluid from the well enters the cylinder through the standing valve and fills the space, causing the plunger to rise. This represents the intake part of the cycle, during which the pressure below the plunger and the discharge pressure ...
    ... these plungers are labeled as: -1, -2, -3, -4, and -5, indicating clearances from 0.001 in to 0.005 in. The amount of fluid leakage through the space (clearance) between the plunger and the cylinder is determined based on experimental data and is expressed in various forms. The general equation ...

  • Tectonic evolution of the Circum-Moesian orocline of the Carpatho-Balkanides: Paleomagnetic constraints

    Emő Márton, Vesna Cvetkov, Miodrag Banješević, Gábor Imre, Aleksandar Pačevski (2024)
    Apuseni-Banat-Timok-Srednogorie belt, danubicum, paleomagnetism, oroclinal bending

  • Projecting short to medium-term effects of carbon emissions trading on Serbia's GDP

    Boban Pavlović, Nikola Trtica (2024)
    This paper presents an approach to assess the short to medium-term effects of the Emissions Trading System (ETS), an economic and climate policy instrument aimed at reducing greenhouse gas emissions, on GDP from the expenditure side. The analysis focuses on Serbia’s electricity sector, which relies heavily on lignite-based pro duction dominated by state-owned enterprises. The obtained projections suggest that in the short term, the introduction of an ETS may lead to slower GDP growth compared to official forecasts. However, ...
    ETS, BDP - rashodni pristup, cene električne energije
    ... European Union, Luxemburg. https://doi.org/10.2760/418422. Bechev, D., 2020. Energy in the western Balkans. Balkans in Europe Policy Advisory Group. https://www.biepag.eu/wp-content/uploads/2023/05/Energy-in-the-Weste rn-Balkans-2.pdf. (Accessed 10 April 2024). Utilities Policy 91 (2024) 101855 ...

  • 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

  • Aнализа и димензионисање примарне и секундарне гасне дистрибутивне мреже ,,Студија случаја Прибој"

    Никола Котлаја (2024)
    У овом раду је приказано идејно решење пројекта гасификације градског насеља, општине Прибој на основу података прикупљених у претходном периоду , од надлежних лица која су са тим упозната и података из сектора широке потрошње које су биле јавно доступни.
    Прибој, природни гас, дистрибуција
    ... Industrijski parkovi d.o.o. Priboj Duo Farma d.o.o. Priboj MHT Products D.O.O. Priboj WOODY WORLD D.O.O. FLEX ACADEMY D.O.O. RAČA Nest Group 011 d.o.o. ADVERTOUT d.o.o. Fap korporacija a.d. Inmold d.o.o. Požega [9] 25 Ta6ena 3.9 – IJompoutba eaca Đ411 xopnopauuje a.0. HaanpaTypa ...

  • Lamprofiri Kolaričke reke (Boranja)

    Luka Jović (2024)
    Lamprofiri su grupa egzotičnih ultrakalijskih stena poznatih po sadrţaju nekompatibilnih elemenata i elemenata retkih zemalja. U našem delu sveta pojavljuju se u okviru ultrakalijskih provincija u Španiji, Italiji, Srbiji, Makedoniji i Turskoj. U Srbiji su zastupljeni ponajviše u zapadnim delovima zemlje, oko opština Ljubovija i Mali Zvornik, ali i u široj okolini Rudnika, Kopaonika i u istočnoj Srbiji. Mnoga ispitivanja sprovedena su u rudnom polju Veliki Majdan u zapadnoj Srbiji sa čije jugoistočne strane protiče Kolarička reka. Ovaj lokalitet ...
    geohemija, lamprofiri, ultrakalijski magmatizam, elementi retkih zemalja, mešanje magmi, mineta, kersantit, flogopit
    ... lamprofiri, ultrakalijski magmatizam, elementi retkih zemalja, mešanje magmi, mineta, kersantit, flogopit; SUMMARY Lamprophyres are an exotic group of ultrapotassic igneous rocks characterized by high concentrations . of incompatible trace elements, including rare earth elements (REEs). In Serbia ...

  • Sinteza i strukturna karakterizacija mikroporoznih arsenata i fosfata

    Sabina Z. Kovač (2015-09-28)
    Predmet rada i istraživanja ove doktorske disertacije su sinteza i strukturnekarakteristike novih kristalnih arsenata i fosfata koji sadrže Mg, K, Ca, Mn, Fe, Co, Ni,Cu, Zn, Sr, Ba i druge katjone. U strukturama arsenata i fosfata, AsO4- i PO4-tetraedrinajčešće se vezuju sa tetraedarski ili oktaedarski koordinisanim katjonima prelaznihmetala formirajući otvorene strukture (slojeve ili 3D mreže) sa širokim opsegomrazličitih topologija. U šupljinama ili porama u obliku povezanih ili nepovezanihkanala, tunela, kaveza i međuslojnog prostora mogu se ugraditi različiti vanmrežni joni(obično ...
    hidrotermalna sinteza, mikroporozna jedinjenja, arsenati, fosfati,rendgenska strukturna analiza
    ... Relativne koordinate strukture aristotipa i struktura DFT-tipa sa odgovarajućim koordinatama izvedenim iz aristotipa. Struktura aristotipa # Space Group ITA number P42/mmc (No.131) 131 # Lattice parameters 7.0750 7.0750 9.0230 90. 90. 90. # Number of independent atoms in the asymmetric ...
    ... Importance, 48, 1‒12. 77. International Tables for Crystallography (2004) Vol. A1: Symmetry relations between space groups (H. Wondratschek and U. Müller, editors). Part 2: Subgroups of the Space Groups. Part 3: Relations of the Wyckoff Positions. Kluwer, Dordrecht. 78. Ito, T., Morimoto, N., Sadanaga ...
    ... of different topologies. In the holes, or pores, which are in the form of a connected or unconnected channels, tunnels, cages and the interlayered space, various non-framework ions (usually alkaline and earth alkaline cations) or molecules (usually small organic molecules) can be incorporated. Therefore ...

  • 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
    ... Beggan, C. D., Alken, P., Aubert, J., Barrois, O., et al. (2015). International Geomagnetic Reference Field: The 12th generation. Earth, Planets and Space. https://doi. org/10.1186/s40623-015-0228-9. Toljić, M., Matenco, L., Ducea, M. N., Stojadinović, U., Milivojević, J., & Ðerić, N. (2012). The ...
    ... Aniso (Bodrás 1990) and ANISOFT 4.2 and 5.1 (Chadima and Jelı́nek 2008; Chadima et al. 2018) based on Jelı́nek (1978, 1981). Test samples from each group were demagnetized in increments with alternating field (AF) (AFD300, Magnon, Dassel and LDA-3A, AGICO) or with the thermal (MMTD80, Magnetic Measurements ...

  • 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

  • Stratigraphic implications of the Mio-Pliocene geodynamics in the area of Mt. Avala: new evidence from Torlak Hill and Beli Potok (Belgrade, Serbia)

    Ljupko Rundić, Meri Ganić, Slobodan Knežević, Dejan Radivojević, Miloš Radonjić (2019)
    Mt. Avala is located on the southern margin of the Pannonian basin (SPB), a border zone between the uplifted morphostructures of the Dinarides and Carpathian-Balkanides. Similar to the Pannonian basin, tectonostratigraphic evolution of the Mt. Avala area during the last 23 Ma has is characterized by syn- and post-rifting processes as well as tectonic inversion. Here, we present the results of field investigations of the Miocene‒Pliocene dynamics that led to different spatial positions of the same stratigraphic units (e.g. ...
    мио-плиоценска геодинамика, јужни Панонски басен, Авалски и Торлак хорст, Белопоточки трог, Србија
    ... NEUBAUER, T., HARZHAUSER, M., KROH, A., GEORGOPOULOU, E. & MANDIC, O. (2014): Replacement names and nomenclatural comments for problematic species-group names in Europe’s Neogene freshwater Gastropoda. Part 2.‒ Zookeys, 429, 13‒46. doi: 10.3897/zookeys.429.7420 PAVELIĆ, D. & KOVAČIĆ, M. (1999): Lower ...

  • 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

  • A Data Driven Approach for Raw Material Terminology

    Olivera Kitanović, Ranka Stanković, Aleksandra Tomašević, Mihailo Škorić, Ivan Babić, Ljiljana Kolonja (2021)
    The research presented in this paper aims at creating a bilingual (sr-en), easily searchable, hypertext, born-digital, corpus-based terminological database of raw material terminology for dictionary production. The approach is based on linking dictionaries related to the raw material domain, both digitally born and printed, into a lexicon structure, aligning terminology from different dictionaries as much as possible. This paper presents the main features of this approach, data used for compilation of the terminological database, the procedure by which it has ...
    sirovine, rudarstvo, terminologija, rečnik, terminološka aplikacija, mobilna aplikacija, digitizacija, leksički podaci, korpusi, otvoreni povezani podaci
    ... for bilingual aligned sentences. For ranking, we have used a weighted score derived from lexical features (e.g., sentence length, number of all no space chars, digits, weird chars, commas, full stops, punctuation, number of all tokens, average token length, max token length, sentences between 15 and ...
    ... prediction using an attention-based model [75], which scores candidate sememes from synonyms, by combining distances of words in the embedding vector space, and derives an attention-based strategy to dynamically balance two kinds of knowledge from a synonymous word set and word embedding vector. Author ...
    ... the Sketch Engine [57,58]). The Python script prepared in the form of a jupyter notebook was published at github [57]. Current work of the Ontolex group is focused on modeling word embeddings, collocations and similar words and we will add this feature when it becomes stable. An example of ontolex-lemon ...

  • Two approaches to compilation of bilingual multi-word terminology lists from lexical resources

    Branislava Šandrih, Cvetana Krstev, Ranka Stanković (2020)
    In this paper, we present two approaches and the implemented system for bilingual terminology extraction that rely on an aligned bilingual domain corpus, a terminology extractor for a target language, and a tool for chunk alignment. The two approaches differ in the way terminology for the source language is obtained: the first relies on an existing domain terminology lexicon, while the second one uses a term extraction tool. For both approaches, four experiments were performed with two parameters being ...
    Linguistics and Language,Software,Artificial Intelligence,Language and Linguistics

  • Tektonske i litostratigrafske karakteristike šireg područja Grivske (Zapadna Srbija)

    Nikola Otašević (2024)
    U ovom radu predstavljene su osnovne geološke karakteristike šireg područja Grivske. U litostratigrafskom pogledu na ovom prostoru prisutne su paleozojske, mezozojske i kenozojske sedimentne, magmatske i metamorfne stene. Tvorevine karbona su predstavljene semimeta-morfisanim tvorevinama.Tvorevine trijaske starosti su predstavljene slojevitim i masivnim krečnjacima, dok su tvorevine jure predstavljeni produktima ofiolitskog melanža. Takođe, prisutne su i tvorevine senona koje su predstavljene masivnim krečnjacima. U neogenoj sukcesiji dominiraju klastiti miocena, dok su u kvartaru zastupljeni različiti tipovi fluvijalnih, deluvijalnih i deluvijalno-proluvijalnih tvorevina. ...
    Arilje, grivska formacija, Drina-Ivanjica, tektonska evolucija

  • Fuzzy Model for Risk Assessment of Machinery Failures

    Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković (2020)
    The main goal of this research was the development of an algorithm for the implementation of negative risk parameters in a synthesis model for a risk level assessment for a specific machine used in the mining industry. Fuzzy sets and fuzzy logic theory, in combination with statistical methods, were applied to analyze the time picture state of the observed machine. Fuzzy logic is presented through fuzzy proposition and a fuzzy composition module. Using these tools, the symmetric position of the ...
    fazi teorija, rizik, otkaz rudarskih mašina
    ... theory proposed by Kahneman and Tversky [23] which is applied to model decision makers’ behavior under risk [24,25]. With this method the outcomes group around the S curve. The model that we are proposing analyzes all of the risky situations, while PT observes only individual cases. PT is applicable ...

  • Application of Project Management Process on Environmental Management System Improvement in Mining-Energy Complexes

    Jelena Malenović Nikolić, Dejan Vasović , Ivana Filipović , Stevan Mušicki, Ivica Ristović (2016)
    menadžment, rudrastvo i energetski kompleksi, okruženje, održivi razvoj, mrežno planiranje
    ... the purpose of organizing data in the field of the environment of Canada, and it eventually began to be used in the practice of OECD, in the working group for the state of the environment [10]. The PSR model is a concept by which anthropogenic activities generate environmental pressures that result in ...

  • Alpine thermal events in the central Serbo-Macedonian Massif (southeastern Serbia)

    Milorad D. Antić, Alexandre Kounov, Branislav Trivić, Andreas Wetzel, Irena Peytcheva, Albrecht von Quadt (2015)
    General Earth and Planetary Sciences

  • Uporedna analiza stabilnosti završnih kosina površinskog kopa „Veliki Krivelj“

    Mihajlo Topalović (2023)
    Površinski kop „Veliki Krivelj“ nalazi se u blizina grada Bora i u neposrednoj blizini sela Krivelj. Od 2018. godine je u vlasništvu kineske kompanije „Zijin“ koja ima udeo od 63% vlasništva celokupnog RTB-a Bor. Na površinskom kopu obavlja se masovna eksploatacija rude bakra opremom visokog kapaciteta. Za bušenje se koriste bušilice prečnika od 250 do 310 mm, a za utovar minirane rude i jalovine bageri čija je zapremina kašike 15 m3 i 22 m3. Za površinski kop „Veliki Krivelj“ ...
    stabilnost kosina, metoda konačnih elemenata, površinski kop, Veliki Krivelj, završna kosina

  • Синтеза, структурне и магнетне особине Ca1-xGdxMnO3 нанопрахова

    Milena Rosić (2014-12-05)
    У оквиру ове докторске тезе, испитиване су оптималне методе за добијањенанопраха – калцијум манганског оксида допираног јонима гадолинијума. Циљистраживања је испитивање одговарајућих прекурсора који су подесни да седобију чисти нано прахови манганита са перовскитском структуром, као имонофазни чврсти раствори са перовскитском структуром. Као подесан методкоришћена је модификована глицин нитратна метода, а од прекурсора нитрати иацетати одговарајућих метала. Модификација глицин нитратне методе се односина делимичну замену нитрата ацетатима, чиме је ублажена бурност реакције.Испитан је различити однос прекурсора, који дају наночестичне ...
    Наноструктурни материјали, Оксиди, Термална анализа,Рендгенструктурна анализа, Магнетна мерења.
    ... diffraction tehnique and Rietveld refinement. Monophase composition of all samples was revealed using XRPD diffraction and Rietveld refinement, Pnma space group but this, that all perovskitephases are deformed as a result of doping with Gd 3+ . Unit cell parameters analysis showed that the increase of ...
    ... ceramics: History and Technology, Journal of the American Ceramic Society, Volume 82, Issue (4), pp. 797-818. Howard, C. J., Stokes, H. T. (1998): Group-Theoretical Analysis of Octahedral Tilting in Perovskites. Acta Cryst. B54, 782-789. Hwang, C.C., Wu, T.Y. (2004): Combustion synthesis of nano ...