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Упит dcterms_subject_txt:fluid production

367 items

  • Novi model za postizanje optimalne proizvodnje na naftnom polju Amal

    Elnori Elmabrouk Ali Elhaddad (2015-04-16)
    Doktorskom disertacijom analizirani su i proučavani problemi proizvodnje nafte iprimenjene metode za njihovo rešavanje na naftnom polju Amal. Ukratko jeprikazana proizvodnje nafte u Libiji, njene karakteristike i rezerve, da bi se videoznačaj ovog naftnog polja.Utvrđeno je da su na naftnom polju Amal ključni problemi koji prate procesproizvodnje taloženje parafina, pojava slojnog peska, neefikasan rad gasliftsistema, neefikasna desalinizacija nafte i ekološki problemi. Proizvodniproblemi, pojedinačno i više njih zajedno, na nekim bušotinama uzrokovali susmanjenje proizvodnje nafte od 40 do 75%. Zbog ...
    nafta, proizvodnja, optimizacija, Amal, Libija
    ... Nouri A., Vaziri H., Chan D., Xiao Y., (2013) Review of Sand Production Prediction Models, Journal of Petroleum Engineering, Volume 2013, Article ID 864981, 16 pages. Rainer H., Lene A., (2013) Influence of wax inhibitor on fluid and deposit properties, Journal of Petroleum Science and Engineering ...
    ... 3.3.1. Postupak pripreme proizvedenog fluida Proces pripreme proizvedenog fluida na naftnom polju Amal koncipiran je tako da omogućava održavanje visokog nivoa proizvodnje. Na slici 3.5 šematski je prikazan postupak pripreme proizvedenog fluida. ...
    ... na osnovu merenih podataka proizvodnje fluida I količine utisnutog gasa. Na slici 5.28. prikazan je izbor korelacije na osnovu merene proizvodnje fluida I količine utisnutog gasa. Na osnovu poklapanja vrednosti utisnutog gasa I izmerene proizvodnje fluida zadovoljavajuće korelacije koje bi mogle ...

  • Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete

    Milan Kragović, Nenad Ristić , Jelena Gulicovski, Andrijana Nedeljković, Snežana Pašalić, Ivica Ristović, Marija Stojmenović (2021)
    sagorevanje lignita, otpadna šljaka, zamena cementa, proizvodnja maltera i betona, fizičko-mehanička i fizičko-hemijska karakterizacija
    ... For that purpose, the optimal conditions for the practical application in mortar and concrete production are defined. Tests related to the use of waste slag as a partial replacement for cement in the production of mortars and concrete are performed in accordance with certain standards, and the detailed ...
    ... construction industry. The different amounts of cement (10%, 15%, 20% and 25%) were replaced with waste slag and silica fumes in mortars and concrete production. Detailed physical–mechanical characterization was performed on the mortar and concrete samples according to standard procedures. Test results ...
    ... predominantly portlandite, quartz, calcite and calcium silicate-oxide. Keywords: lignite combustion; waste slag; cement replacement; mortar and concrete production; physical–mechanical and physical–chemical characterization 1. Introduction Coal is a solid fuel that has been used as a primary fossil fuel for ...

  • 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

  • Characterization and Environmental Evaluation of Recycled Aggregates from Construction and Demolition Waste in Belgrade City Area (Serbia)

    Filip Abramović, Miroslav Popović, Vladimir Simić, Vesna Matović, Radmila Šerović (2024)
    General Materials Science

  • Effectiveness Analysis of Different Bucket-wheel Excavators

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić (2021)
    Coal production in open-pit lignite mines in the Republic of Serbia is performed with continuous work systems. In addition to coal production, the same systems are used for the exploitation of large quantities of overburden. According to the reliability concept, continuous systems are in linear connection. If the failure occurs in one part of the system, that will produce a downtime of the entire system. The initial and most important factor of continuous systems is the bucket-wheel excavator. It ...
    bucket-wheel excavator, open-pit coal mine, mining, multi-criteria decision methods

  • Automatic construction of a morphological dictionary of multi-word units

    Cvetana Krstev, Ranka Stanković, Ivan Obradović, Duško Vitas, Miloš Utvić (2010)
    The development of a comprehensive morphological dictionary of multi-word units for Serbian is a very demanding task, due to the complexity of Serbian morphology. Manual production of such a dictionary proved to be extremely time-consuming. In this paper we present a procedure that automatically produces dictionary lemmas for a given list of multi-word units. To accomplish this task the procedure relies on data in e-dictionaries of Serbian simple words, which are already well developed. We also offer an evaluation ...
    electronic dictionary, Serbian, morphology, inflection, multiwordn units, noun phrases, query expansion
    ... tional class is associated with one inflectional transducer (as described in [9]) that controls the production of all inflected forms. The forms/lemmas ratio in Table 1 shows that a direct production of DELACF dictionary is out of the question for Serbian, though it may seem possible for some other languages ...
    ... look-up used in the module for (automated) production of DELAC entries. To manipulate the strategy in the form of XML documents our tool relies on W3C standard languages XQuery and XSLT supported by .NET. The user interface of the module for automatic production of DELAC lemmas is very friendly. A user ...
    ... comprehensive morphological dictio- nary of multi-word units for Serbian is a very demanding task, due to the complexity of Serbian morphology. Manual production of such a dictio- nary proved to be extremely time-consuming. In this paper we present a procedure that automatically produces dictionary lemmas ...

  • Valorization of non-balanced coal reserves in Serbia for underground coal gasification

    David Petrović, Lazar Kričak, Milanka Negovanović, Stefan Milanović, Jovan Marković, Nikola Simić, Ljubisav Stamenić (2019)
    In the name of a better and safer energy future, it is our responsibility to focus our knowledge and activities to save on imported liquid and gas fossil fuels, as well as coal on which energy security of Serbia is based. The rationalization in the use of available energy resources certainly positively affects economy and the environment of a country. This paper indicates motivations for the application of the underground coal gasification process, as well as surface gasification for ...
    ugalj, gasifikacija, zaštita životne sredine, skladištenje, solarna
    ... various design checks it is sometimes operated with the parameter of the gas production per 1 m thickness of the layer. Calculating per 1 m of the layer thickness, this gas production becomes 1783 mi /h. The obtained gas production, ,, for the coal layer is 70 x 50 x 6, and it corresponds to the initial ...
    ... Reserves in Serbia for ... 4068 THERMAL SCIENCE: Year 2019, Vol. 23, No. 6B, pp. 4067-4081 Electricity CO, separation production and gas processing Injection - Production well well | Oxidizer Synthesis gas Feasible UCG (O,, H,O) (Hx, CH„ CO,, CO) depths: 200 – 2,000 m Target coal seam ...
    ... vertical wells: one injection and one production), the gasification initiator (oxidant and possibly steam) from the compressor station at high temperature would be pumpećd to catalyze gasification reactions and transport the resulting gas mixture through production well. The final quality of gas — syngas ...

  • Utilizing sewage wastewater heat in district heating systems in Serbia: effects on sustainability

    Marija Živković, Dejan Ivezić (2021)
    Transformation of the heating sector is recognized as being essential for ensuring reliable and afordable energy services provided with reduced consumption of energy sources and diminished impact on the environment and less import dependency. The possibility of utilizing energy sources that otherwise would be wasted needs to be considered and treated as a big advantage of district heating systems. Despite many advantages, sewage wastewater heat is still a mostly unused resource at the global level and a totally unused ...
    рекуперација топлоте из отпадних вода, систем даљинског грејања, топлотне пумпе, енергетске уштеде, емисија угљендиоксида, енергетска безбедност, Србија
    ... heat pumps to existing DH systems without jeopardizing the profitability of current production plants. Different-sized DH systems have been simulated to explore how increasing the share of heat pump production influences DH systems. Data on heat pump performance in an Olympic village in Vancouver ...
    ... treated wastewater by heat pumps, in all Serbian cities with DH systems, would result in the production of 6360 TJ of heat. As a consequence of the introduction of more efficient technology in heat production, the primary energy factor will be reduced to 1.467. This value is also highly influenced by ...
    ... recoverable heat energy potential of wastewater is used for evaluation of some effects that could be obtained through its full utilization for heat production in the existing district heating systems. Three groups of indicators are selected for analysis focusing on district heating systems’ energy performance ...

  • Стратешко планирање функционалности подземних просторија моделом прогнозе деформација

    Лука Црногорац (2023)
    Релативно велике деформације подградне конструкције у подземним рудницима угља у Републици Србији представљају један од главних проблема за постизање планиране производње угља. Деформације подграде су директна последица статичких и динамичких оптерећења стенске масе и у многоме зависе и од времена трајања изложености подграде утицају подземног притиска. Код ниско механизованог радног процеса долази до повећаног излагања подземних просторија утицају подземног притиска услед дугог производног циклуса који је често пропраћен застојима у раду. Веома често подземне просторије се санирају и по ...
    подземне просторије, подграда, прогноза деформација, стратешко планирање

  • Double traveling valve increases rod-pump efficiency

    Miloš Petrović, Bojan Martinović, Milica Ješić, Miroslav Crnogorac (2023)
    Traditional sucker rod pumps (SRP) use a single traveling valve, but recent double traveling valve innovations have improved SRP performance and efficiency in field applications with double traveling valves installed in pumps with top mechanical seating. The valves sealed better and produced similar fluid volumes compared with the previous single-valve pumps. They also enabled a reduction in pump diameter and optimized usage of surface equipment. Overall, the double travel valve SRPs produced stable production rates and annual production targets.
    дубинска пумпа на клипним шипкама, производња нафте, ефикасност

  • Evaluation of the effects of wastewater heat pump integration into district heating systems by simulation

    Dejan Ivezić, Marija Živković, Dimitrije Manić, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović (2023)
    The integration of wastewater heat pumps (using purified water) in district heating systems is analyzed in this paper. The simulation procedure is proposed to analyze the impacts of stochasticity of purified water temperature and flow to heat pump integration and operation. The analysis includes calculation of the daily and seasonal coefficient of performance, as well as fossil fuel savings and CO2 emission reduction due to wastewater heat pump use. The proposed procedure is implemented for the case study in ...
    otpadne vode, toplotna pumpa, daljinsko grejanje, simulacija

  • Fluid Evolution of the Čukaru Peki Cu-Au Porphyry System (East Serbia) inferred from a fluid inclusion study

    Velojić Miloš, Jelenković Rade, Cvetković Vladica (2020)
    Borska metalogenetska zona, Timočki magmatski kompleks, fluidne inkluzije, porfirska ležišta bakra, masivni sulfidi, slani rastvori, ključanje fluida

  • Convective heat transfer in centrifugal pumps lifted wells: the case of South-Eastern Europe waxy wells

    Bojan Martinovic, Marija Živković, Branko Grubač (2021)
    Electric submersible pumps (ESP) are applied in wells where additional energy is needed to ensure discharge of the fluid to the surface through the tubing. At the discharge side of the pump the fluid has bigger velocity, thus the pump induces a forced convection between the fluid and the tubing inner surface. Understanding of convective heat transfer in wellbores and analyses of influential parameters provides a possibility to optimise value of convective heat transfer coefficient in order to avoid ...
    prenos toplote konvekcijom, ESP pumpa, svojstva fluida, problemi u radu bušotine

  • Geohemijske karakteristike slojnih fluida naftnih, naftno-gasnih ležišta jugoistočnog dela Panonskog basena i korišćenje nekih geohemijskih pokazatelja pri pronalaženju i istraživanju ležišta nafte i gasa

    Miodrag Šarković (1972)
    Slojni fluidi, naftna, gasna ležišta,istraživanje ležišta, Panonski basen

  • ‘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

  • Development of an integrated model for open-pit-mine discontinuous haulage system optimization

    Miodrag Čelebić, Dragoljub Bajić, Sanja Bajić, Mirjana Banković, Duško Torbica, Aleksej Milošević , Dejan Stevanović (2024)
    equipment selection, mine mechanization, expert judgment, linguistic variables, MCDM, FAHP

  • Evaluation And Perspectives Of Underground Coal Mines In Serbia

    Vladimir Milisavljević, Milena Lekić, Ivica Ristović, Vojin Čokorilo, Aleksandar Cvjetić (2017)
    ... major coal producers in Europe, with over 38 Mt of coal per year. But most of this production is achieved in lignite open cast mines, which in 2016 produced 37.6 million tonnes [1]. On the other hand, combined production of all underground coal mines in Public Company for Underground Coal Exploitation ...
    ... 3 4 1 2 2 1 Jasenovac 2 2 3 2 3 2 2 Lubnica 4 4 2 3 2 2 2 Štavalj 5 3 3 3 3 1 1 Table 3. Production from PCUCE mines, in period 2010-2015 Year Coal production (t) Vrška Čuka Ibarski rudnici REMBAS Soko Bogovina Jasenovac Lubnica Štavalj JP PEU 2010 7,061 101,200 113 ...
    ... project "Research on possibility for AT (Advanced Technology) rockbolting application in mines for the purpose of increasing work safety and production efficiency" (TR33025). Development of this project is financed by Ministry of Science and Technological Development, Republic of Serbia. ...

  • Application of machine learning for diagnosing the operation of a deep well pump in oil production

    Maja Trikić (2024)
    This paper will thoroughly examine how machine learning can improve the diagnosis of deep well pumps by analyzing the role and function of the pumps, dynamograms, sensor technologies, and diagnostic methods.Our analysis will provide insights into modern techniques and approaches for enhancing the performance and reliability of oil production systems, targeting cost reduction and increased operational efficiency.
    deep well pump, dynamograms, machine learning, diagnostics of operating coditions,Random Forest, XGBoost
    ... weight of the sucker rods immersed in the fluid, the weight of the fluid column in the tubing above the downhole pump, pressure load on the tubing and annular space, the weight of the fluid column in the annulus, and frictional forces arising: from fluid movement through the tubing. Dynamic loads ...
    ... pressure, which is an indicator of the increase in potential energy of the fluid. The efficiency of the pump depends on its ability to convert mechanical energy into the potential energy of the fluid. Free gas in the fluid can negatively affect the pump's efficiency, especially at low pressure and ...
    ... plunger lifts fluid from the annular space between the tubing and rods (see Figure 2.2). At the same time, the suction valve is open, allowing fluid to enter the cylinder through a filter placed at the bottom of the pump. During the downward stroke, the plunger moves through the fluid and fills the ...

  • 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

  • Rule-based Automatic Multi-word Term Extraction and Lemmatization

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Biljana Lazić, Aleksandra Trtovac (2016)
    In this paper we present a rule-based method for multi-word term extraction that relies on extensive lexical resources in the form of electronic dictionaries and finite-state transducers for modelling various syntactic structures of multi-word terms. The same technology is used for lemmatization of extracted multi-word terms, which is unavoidable for highly inflected languages in order to pass extracted data to evaluators and subsequently to terminological e-dictionaries and databases. The approach is illustrated on a corpus of Serbian texts from ...
    term extraction, terminology, multi-word units, lemmatization, finite-state transducers
    ... retained. This form, together with information about its structure is enough for automatic production of the e-dictionary lemma (DELAC), while information provided with the lemma enables subsequent production of all its inflected forms (DELACF). Graph Num Recognized form Frequency Temporary ...
    ... T-Score, LLR, and Keyness). Mean average precision for retrieval of MWU forms ranges from 0.789 to 0.804, while mean average precision of lemma production ranges from 0.956 to 0.960. The evaluation showed that 94% of distinct multi-word forms were evaluated as proper multi-word units, and among them ...
    ... e-dictionaries and grammars developed within the University of Belgrade Human Language Technology Group (Vitas et al., 2012). For our approach, production of lemmas for various forms of MWTs extracted from a corpus is necessary for two main reasons. Firstly, the evaluators need to be supplied ...