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Упит dcterms_subject_txt:fluid loss control

351 items

  • 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
    ... amount of fluid that each of the observed artificial lift methods can produce, the greater the amount of fluid produced, the fewer the methods can be applied. Based on this value of production is translated into grades. Parameter B3 represents the temperature. Based on the optimal and maximum fluid temperature ...
    ... of the observed artificial lift methods can be applied, the higher the temperature of the fluid, the fewer the methods that can be applied. Parameter B4 represents the density of the fluid. The values of fluid density are translated into grades based on the distribution of oil by density [19]: light—0 ...
    ... decreases in the production fluid. Parameter C2 represents solid particles. With the rise of solid particles in the production fluid, the number of artificial methods that can be used is reduced. Parameter C3 represents GOR. With the increase in the gas factor in the production fluid, the efficiency of ...

  • Хазард од клизишта у Србији у 21. веку

    Biljana Abolmasov (2019)
    клизишта, хазард од клизишта, промене климе
    ... D. F. VanDine (2013). Classification, Description, Caus Effects-Canadian Technical Guidelines and Best Practices related t national initiative for loss reduction, Geological Survey �f Canad 2013. [6] Hungr O., Leroueil S., Picarelli L. (2012). Varnes classification o an update. Proceedings of the ...
    ... D., D. F. VanDine (2013). Classification, Description, Cau Effects-Canadian Technical Guidelines and Best Practices related national initiative for loss reduction, Geological Survey f Cana 2013. Hungr O., Leroueil S., Picarelli L. (2012). Varnes classification an update. Proceedings dintthimdtli onal’ ...

  • Strategic Environmental Assessment and the precautionary principle in the spatial planning of wind farms – European experience in Serbia

    Boško Josimović, Aleksandar Cvjetić, Danilo Furundžić (2021)
    Spatial determination planning is at an initial and very sensitive step in the development of wind farms. On one hand, it is important to maximize the potential of wind in a particular area, and on the other hand, it is important to achieve environmental protection (including the human population and natural heritage) in the same space at the same time. With this in mind, it is important to balance all the requirements that are relevant for reaching the optimal ...
    Obnovljiva energija, Održivost, Životna sredina

  • 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

  • Imputing missing data using grey system theory and the biplot method to forecast groundwater levels and yields

    Jelena Ratković, Dušan Polomčić, Zoran Gligorić, Dragoljub Bajić (2022)
    Groundwater management is one of today’s important tasks. It has become necessary to seek out increasingly reliable methods to conserve groundwater resources. Dependable forecasting of the amounts of groundwater that can be abstracted in a sustainable manner requires longterm monitoring of the groundwater regime (rate of abstraction and groundwater levels). Monitoring of the groundwater source for the town of Bečej, Serbia had been disrupted for multiple years. The objective of the paper is to assess the possibility of reinterpreting ...
    upravljanje podzemnim vodama, izvorište podzemnih voda, prognoziranje

  • Geodynamics of basins above subducted slabs: An integrated modelling study of tectonics, sedimentation, and magmatism in the Timok Magmatic Complex

    Uros Stojadinovic, Marinko Toljic, Branislav Trivic, Radoje Pantovic, Danica Sreckovic-Batocanin, Nemanja Krstekanic, Bojan Kostic, Milos Velojic, Jelena Stefanovic, Nikola Randjelovic, Maja Males (2024)
    Timok Magmatic Complex, Neotethys subduction, basin geodynamics, analogue modelling

  • The influence of Al<sup>3+</sup>ion on porcine pepsin activity<i>in vitro</i>

    Vesna M. Pavelkić, Kristina R. Gopcević, Danijela Z. Krstić, Marija A. Ilić (2008)
    The in vitro effect of Al3þ ions in the concentration range 1.7·1026M–8.7·1023M on pepsin activity at pH 2, via kinetic parameters and its electrophoretic mobility was evaluated. Kinetic study demonstrated the existence of an activation effect of Al3þ at pH 2 on pepsin molecule. Kinetic analysis with respect to concentrations of haemoglobin showed that Al3þ ions increase the maximal velocity (Vmax) and kcat values rather than apparent affinity for substrate (KS) implying the non-competitive nature of activation which indicated ...
    Пепсин, алуминијум, кинетика, активација, електрофоретска мобилност
    ... acidified with 0.0!M HCI, pH2), carried out on Beckman UV 5260 UV-VIS spectrophotometer with an electro-thermaltemperature control cell unit. The temperature control performed with DANA - Digital voltmeter model 4800 with chromel-alumel thermocouples. A quartz cell with a 1 cm path length ...
    ... enzyme-catalyzed measured rate of hydrolysis of denatured haemoglobin (Hb) substrate was used for evaluation of enzyme activity in the absence (control) and presence of Al ions [26]. Pepsin activity was determined in an incubation medium containing: 1mL of pepsin solution (20 ug/mL. in 0.0,M ...
    ... concentrations of metal ions induced increase of enzymatic activity. Values are expressed as the percent of increased activity related to the control, which considered as 100%. Aluminium was found to stimulate the enzyme activity 250 _ APP1(M % of activation »0 | IA ](M) % s | . 0 a 1.7x10 ...

  • The Impact Assessment of NO2 Emission from District Heating Plant on Local Air Quality, the Case of Zemun, Belgrade

    Boban Pavlović, Uroš Pantelić, Marija Živković, Dejan Ivezić (2021)
    The Belgrade district heating system relies on fossil fuels in heat production, where natural gas has the largest share of around 95% and fuel oil with around 4.4%. The Zemun heating plant is completely fueled with fuel oil. Currently, it is the largest plant that is not fueled with natural gas. The objective of this paper is to assess the impact of NO2 from the Zemun heating plant on local air quality by analyzing and comparing the concentration of ...
    NO2, Zagađenje vazduha, Kvalitet vazduh na lokalnom nivou, Model disperzije, AERMOD, Daljinsko grejanje, Beograd

  • Spatial distribution of major and trace elements in artificial lakes in Serbia: health risk indices and suitability of water for drinking and irrigation purposes

    Goran Marković, Aleksandar Ž. Kostić, Nebojša Đ. Pantelić, Radojka Maletić, Jana Štrbački, Jovan Cakić, Lazar Kaluđerović, Biljana P. Dojčinović, Angelo Maria Giuffrè, Jelena B. Popović-Djordjević (2023)
    Lakes and reservoirs are the main water resources for household, irrigation, and industrial use. Hence, it is necessary to control water pollution and have reliable information on water quality, which refers to its suitability for a particular purpose. The main objective of this study was to evaluate the suitability of water for drinking and irrigation purposes from ten artificial lakes on the territory of the Republic of Serbia. The physicochemical parameters were determined using standard analytical methods, whereas the ...
    Management, Monitoring, Policy and Law, Pollution, General Environmental Science, General Medicine

  • 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

  • Ефикасност дистрибуције и коришћења природног гаса у домаћинствима

    Dejan Brkić (2010-03-30)
    Природни гас ће се у будућности све више користити као енергент за подмиривање грејних потреба становништва у српским градовима. Стога је потребно изнаћи најповољнији начин употребе природног гаса. Природни гас се може користити за подмирење грејних потреба становништва на два дијаметрално супростављена начина, и то директно, тако што би се гас директно уводио у зграде путем дистрибутивног система за снабдевање гасом и затим сагоревао у гасном котлу којим је сваки стан опремљен (гасни дистрибутивни систем), или индиректно, тако што ...
    prirоdni gаs, distribuciја gаsа,grејаnjе, cеvоvоdi, cеvоvоdnе mrеžе,fаktоr trеnjа pri prоtоku fluidа,urbаnizаm
    ...  Calculating friction loss: Darcy‐Weisbach formula vs. Hazen‐ Williams. www.vikongcorp.com (на енглеском)  188. Mathews, E.H., Kohler, P.A.J. 1995. A numerical optimization procedure for complex pipe  and duct network design. International Journal of Numerical Methods for Heat & Fluid  Flow 5(5),445‐457 ...
    ... frictional factor for  fluid flow in pipelines. Proceedings, Thirty‐Third Workshop on Geothermal Reservoir  Engineering, Stanford University, Stanford, California, January 28‐30, 2008, SGP‐TR‐185.  (на енглеском)  287. von Bernuth, R.D. 1990. Simple and accurate friction loss equation for plastic pipe ...
    ... сти ε (која је својство саме цеви) зависи и од својстава флуида (вискозности и  густине  флуида),  aли  и  од  брзине  протока  флуида.  Поред  тога  у  појединим  режимима  ефективни утицај храпавости може да буде умањен из разлога што флуид формира танак  слој уз сам унутрашњи зид који у неку руку има ...

  • Ground surface subsidence monitoring using sentinel-1 in the “Kostolac” open pit coal mine

    Zoran Gojković, Milan Kilibarda, Ljiljana Brajović, Miloš Marjanović, Aleksandar Milutinović, Aleksandar Ganić (2023)
    Open pit coal mining affects surrounding populated areas, resulting in terrain surface deformation. Surface deformation should be monitored as often as possible to control deformations and prevent potential incidents. This paper analyzes time series deformation estimated from the Sentinel-1 satellite images using the Persistent Scatterer Interferometry method to monitor subsidence rates caused by open pit mining activities. It is possible to measure deformations using classical geodetic methods, but those are rarely used in practice because they are time-consuming and ...
    Sentinel-1 InSAR, слегање, рударствo, интерферометрија, даљинска детекција, Костолац

  • Hydraulic impact of pressure transients from water conveyance tunnel on the complex hydrogeological system: A case study HPP

    Igor Jemcov, Maja Todorović, Aleksandar Jemcov, Marina Ćuk Đurović (2024)
    Tunel pod pritiskom, Unutrašnji pijezometri, Tranzijenti pritiska, Karstna izdan, Pukotinska izdan, Hidraulički odziv
    ... fractured massif: la Linea Tunnel project Colombia. Appl Geochem (2018) C.B. Zhou et ol. Groundwater flow through fractured rocks and seepage control in geotechnical engineering: rheories and practices JRMGE (2023) B.Q. Zhou et aL Assessing the impact of tunnelling on karst groundwater balance ...
    ... fractured massif: la Linea Tunnel project Colombia. Appl Geochem (2018) C.B. Zhou et ol. Groundwater flow through fractured rocks and seepage control in geotechnical engineering: theories and practices JRMGE [2023} B.Q. Zhou et aL Assessing the impact of tunnelling on karst groundwater balance ...

  • Indeksi kontrole održavanja i korišćenja rotornog bagera

    Jovana Mitrović, Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić, Filip Miletić (2023)
    Razvoj površinske eksploatacije se u velikom stepenu zasniva na svestranoj mehanizaciji rudarskih radova. Kako bi se zadovoljili potrebni kapaciteti, neophodna je primena savremene mehanizacije, velikih kapaciteta i pouzdanosti u radu. Naime, sa stepenom povećanja mehanizovanosti radova smanjuje se broj zaposlenih radnika, povećava produktivnost rada, smanjuju troškovi po jedinici proizvoda, a samim tim i povećava ekonomičnost površinske eksploatacije. Predmet istraživanja su rotorni bageri SRs 1200 koji predstavljaju samohodne mašine kontinuiranog dejstva namenjene za otkopavanje jalovine i korisne supstance na površinskim ...
    rudarstvo, rotorni bager, indeksi održavanja, indeksi korišćenja, TOPSIS

  • The Late Devonian contraction along the Precaspian Basin north margin: Transpressional range building in the intracratonic domain

    Novak Novčić, Marinko Toljić (2023)
    The evolution of intraplate sedimentary basins located in the vicinity of an active convergent plate boundary is often controlled by the collisional dynamics of the adjacent orogen. The transfer of compression from the orogen to the platform's interior results in the formation of complex structural geometry and kinematics that often reactivate older crustal faults, focus far-field stresses and control the evolution of associated sedimentary basins. One place where this localisation can be optimally understood is the Precaspian Basin, situated ...
    Intrakratonske deformacije, transpresija, kosa kompresija, krustalni rasedi, intrakratonski transfer stresa, kontrakcioni blokovi

  • Model upravljanja investicionim projektima otvaranja površinskih kopova uglja

    Cvjetko P. Stojanović (2015-04-27)
    Brze promene u okruženju pred rukovodioce postavljaju mnogobrojne zahteve,pre svega, one koji se tiču ostvarenja ciljeva u zadatom vremenu i raspoloživimsredstvima što zahteva fleksibilan pristup u organizovanju aktivnosti i efikasnost unjihovom sprovođenju.Upravljanje projektima, bilo koje vrste, suštinski, predstavlja veoma složenproces odlučivanja uslovljen velikim brojem ulaznih faktora. Ti faktori treba daomoguće fokusiranje na prioritete i ciljeve, praćenje realizacije, fleksibilnost uprevazilaženju teškoća, prilagođavanje promenama, te kontrolu nad ostvarenimrezultatima. Ovakav način upravljanja zahteva korišćenje proverenih tehnika i alata tetimski rad angažovanih na ...
    Projekat, upravljanje, metodologija, površinska eksploatacija, model

  • Model upravljanja investicionim projektima otvaranja površinskih kopova uglja

    Cvjetko P. Stojanović (2015-04-27)
    Brze promene u okruženju pred rukovodioce postavljaju mnogobrojne zahteve,pre svega, one koji se tiču ostvarenja ciljeva u zadatom vremenu i raspoloživimsredstvima što zahteva fleksibilan pristup u organizovanju aktivnosti i efikasnost unjihovom sprovođenju.Upravljanje projektima, bilo koje vrste, suštinski, predstavlja veoma složenproces odlučivanja uslovljen velikim brojem ulaznih faktora. Ti faktori treba daomoguće fokusiranje na prioritete i ciljeve, praćenje realizacije, fleksibilnost uprevazilaženju teškoća, prilagođavanje promenama, te kontrolu nad ostvarenimrezultatima. Ovakav način upravljanja zahteva korišćenje proverenih tehnika i alata tetimski rad angažovanih na ...
    Projekat, upravljanje, metodologija, površinska eksploatacija, model

  • Fizičko-hemijsko raspadanje krečnjaka ugrađenih u objekte Beogradske tvrđave i mogućnost konsolidacije

    Maja Z. Franković (2022)
    Beogradska tvrđava, spomenik kulture od izuzetnog značaja za Republiku Srbiju, izgrađena je od krečnjaka badenske starosti. Njihova litološka heterogenost, u sadejstvu sa uticajima okruženja, rezultira visokim intenzitetima raspadanja. Korelacijom intrinzičnih sa ekstrinzičnim faktorima, definisani su fizičko-hemijski procesi raspadanja ugrađenih mikrofacija krečnjaka. Aplikacijom neorganskih konsolidanata na karbonatnoj bazi (nano-kreča i Ca-acetoacetata) i alkoksisilana, te korelacijom fizičko-mehaničkih svojstava pre i nakon tretmana, ispitana je efektivnost u pogledu zaustavljanja dekohezije krečnjaka. Određivanjem petroloških, tehničkih svojstava i mapiranjem formi raspadanja Mračne kapije kao ...
    krečnjaci, forme i intenziteti degradacije, fizičko-hemijsko raspadanje, konsolidacija, nano-kreč, Ca-acetoacetat, alkoksisilani, Mračna kapija

  • A Tel Platform Blending Academic And Entrepreneurial Knowledge

    Ivan Obradović, Ranka Stanković, Jelena Prodanović, Olivera Kitanović (2013)
    ... graduate students working for enterprises. BAEKTEL encompasses tools, learning content and implementation resources. It also features a backend control panel offering to university teachers the possibility to track the progress of their students, and to supervisors of graduate students who started ...
    ... of best practice design principles and licensing tools aimed at facilitating open publishing of materials. BAEKTEL also features a backend control panel offering the possibility within the academic environment for university teachers to track the progress of their students while using the ...
    ... experience for the students through implementation of software based virtual laboratories (VL) for engineering disciplines. BAEKTEL backend control panel also provides life-long learning opportunities for graduate students who started to work in companies. Their supervisors, the same as ...

  • Some examples of interactions between certain rare earth elements and soil

    Zlatko Nikolovski, Jelena Isailović, Dejan Jeremić, Sabina Kovač, Ilija Brčeski (2021)
    Freundlich adsorption isotherm, sequential extraction, metallic ions, ICP-OES
    ... bottles at rotational shaker with 100 mL of 1 mol L-1 ammonia-acetate solution each. The pH value of obtained suspensions amounted to about 7. The control test was formed of 100 mL extraction agent. Extraction at rotational shaker lasted for two hours. Upon extraction the samples were left to age for ...
    ... to the initial bottles. Phase III: to each soil from Phase II, 50 mL of 0.4 mol L-1 oxalic acid and 0.4 mol L-1 ammonia oxalate was added. The control test was made up of the extraction solutions. At rotational shaker the extraction lasted for nine hours, following which the suspensions were left ...
    ... glass with suspension from Phase III, 10 mL of 30 % hydrogen peroxide was added, which was acidified by concentrated nitric acid up to pH 2. The control test was represented only by the acid solution of hydrogen peroxide. The glasses were covered by watch glass and were heated for two hours at water ...