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Упит dcterms_subject_txt:fluid production

367 items

  • Steel Arch Support Deformations Forecast Model Based on Grey–Stochastic Simulation and Autoregressive Process

    Luka Crnogorac, Suzana Lutovac, Rade Tokalić, Miloš Gligorić, Zoran Gligorić (2023)
    Relatively large deformations of the steel arch support in underground coal mines in the Republic of Serbia present one of the main problems for achieving the planned production of coal. Monitoring of the critical sections of the steel arch support in the underground roadways is necessary to gather quality data for the development of a forecasting model. With a new generation of 3D laser scanners that can be used in potentially explosive environments (ATEX), deformation monitoring is facilitated, while ...
    čelična podgrada, prognoza deformacija, vremenske serije, grey-stohastička simulacija, autoregresija, podzemni rudnik uglja

  • Mineralogical Discrimination between Authentic and Recent Imitations of Pottery Manufacture in Zlakusa, Serbia

    Maja Milošević, Mihovil Logar, Biljana Đorđević (2021)
    ... Humanity. Mass production of utilitarian ceramics and pottery items occurred in the Neolithic, mid 7th millennium BC, in the area of current territory of Serbia. What makes it a unique phenomenon, in technological terms, is the fact that with the discovery of new techniques and production processes ...
    ... oven), stands out. A microscopic examination of the thin sections revealed a uniform mineral composition and porosity. For sample -5- a specific fluid-structure is consistent with the way it was introduced by the application of a mould. The measurements of moisture absorption showed that in this ...
    ... horizontal lines or their absence, smooth surface and the presence of irregularities are the main indicators for assessing differences in the production of vessels. The maximum temperature, heating mode and oxidation atmosphere in the ovens were not the same for all samples. In that aspect sample ...

  • Koncept prediktivnog održavanja 4.0 (PdM) u energetici – konekcija sa budućom primenom Industrije 5.0

    Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić, Miloš Tanasijević, Filip Miletić (2022)
    Četvrtu industrijsku revoluciju - Industrija 4.0 karakteriše upotreba cyber-fizičkih sistema. Da bi se postigla optimalna strategija održavanja (ali i proizvodnje), neophodno je razviti sisteme koji podržavaju napredne inteligentne sisteme održavanja ili tehnologije pametnog održavanja. Iz toga su proizašli postulati Prediktivnog održavanja 4.0 koji definišu veoma blisku budućnost u oblasti održavanja tehničkih sistema. Prediktivno održavanje 4.0 uključuje iskorišćenje snage veštačke inteligencije za stvaranje stalnog uvida u otkrivanje uzroka i anomalija u radu opreme, koje se ne otkrivaju kognitivnim moćima. Drugim ...
    energetika, prediktivno održavanje 4.0, industrija 4.0, industrija 5.0

  • An Experimental Investigation of the Environmental Risk of a Metallurgical Waste Deposit

    Jasmina Dedić , Jelena Djokic , Jovana Galjak, Gordana Milentijević, Dragan Lazarevic, Živče Šarkočević, Milena Lekić (2022)
    The aim of this study is to investigate the environmental risk of long-term metallurgical waste disposal. The investigated site was used for the open storage of lead and zinc waste materials originating from a lead smelter and refinery. Even after remediation was performed, the soil in the close vicinity of the metallurgical waste deposit was heavily loaded with heavy metals and arsenic. The pollutants were bound in various compounds in the form of sulfides, oxides, and chlorides, as well ...
    otpad od proizvodnje olova, remedijacija, rizik po životnu sreinu, BCR sekvencijalna ekstrakcija

  • Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry

    Steven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti (2021)
    Self-engineering is a relatively new branch of knowledge that aims to understand how systems could “autonomously” re-configure or repair themselves without the intervention of the operators. A direct field of application is within the maintenance spectrum. Having systems or machines capable of self-detecting or even self-repairing could represent a game-changer, in capital asset fields such as the mining industry in particular. This paper aims to investigate the possible benefits and challenges of self-engineering / self-maintenance concerning mining machines, specifically bucket-wheel ...
    self-engineering, self-maintenance, maintenance operations, mining industry, bucket-wheel excavator, gearbox revitalization

  • Prioritization of strategic measures for strengthening the security of supply of the Serbian natural gas sector

    Boban Pavlović, Dejan Ivezić, Marija Živković (2020)
    To strengthen the security of supply of the Serbian gas sector, it is necessary to analyze the impact of planned strategic measures. The analysis involves the identification of the most influential threats to the security of natural gas supply and prioritization of the strategic measures for overcoming the consequences of threats. The proposed methodology is based on Fuzzy Analytic Hierarchy Process. The obtained weights for the identified threats and strategic measures are formed according to experts' judgments. The results ...
    Sigurnost snabdevanja, Donošenje odluka, Snabdevanje prirodnim gasom, Fazi AHP, Energetski indikatori

  • 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
    ... positions. The discharge rates of the production wells of the other groundwater sources in the area were specified based on available technical reports [26], as constant values throughout the period. These included the MSK groundwater source, operating two production wells with a total capacity of 54 ...
    ... 54 l/s; the TM groundwater source, using a single production well with a discharge rate of 35 l/s; and the LŽT - Kikinda groundwater source, which operated two production wells with a total capacity of 50 l/s. Effective infiltration. In the overall groundwater balance, for the reasons stated ...
    ... 4 shows the three-dimensional hydrogeological model of the sectional view of Šumice. The tapped water-bearing horizon is shown in blue, with production well screens shown in green. As previously mentioned, the overlying and underlying strata of this water-bearing horizon are comprised of semi-permable ...

  • Towards a Mining Equipment Ontology

    Ranka Stanković, Ivan Obradović, Olivera Kitanović, Ljiljana Kolonja (2012)
    ... registering of realized an planned production for each day, month and year, as well as for each type of material (coal or overburden) the excavator worked with. The data on the mechanization operation are used for creating reports that show the realized and planned production for a specific period, the realized ...
    ... taxonomy and a thesaurus on the semantic scale, with the final goal of upgrading it into an ontology. One of the intended uses of the RudOnto is for production of appropriate terminological resources in sub-fields of mining engineering, such as, planning and management of exploitation, mine safety or mining ...
    ... they exist, are represented as synonyms. As a general terminological resource for mining engineering RudOnto can be used, among other things, for production of terminological resource in corresponding sub-fields, often in the form of controlled dictionaries, which are consistent collections of terms ...

  • 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
    ... of wall roughness on friction factors for pipe and channel flows.  Journal of Fluid Mechanics 613, 35‐53. (на енглеском)  147. Holmgren, K., Amiri, S. 2007. Internalising external costs of electricity and heat  production in a municipal energy system. Energy Policy 35(10), 5242–5253. (на  енглеском)  ...
    ... on of the effect of surface  roughness and texture on fluid flow‐past, present, and future. International Journal of  Thermal Sciences 45(10), 962‐968. (на енглеском)  275. Ter Brugge, R. 1984. Spatial structure in relation to energy production and consumption.  Tijdschrift voor Economischeen Socia ...
    ... 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 ...

  • BEYOND 2020 - Geology explorations and open pit activities affectation in reclamation designing in Kolubara Coal Mines (KCM) Serbia, new considerations

    Bojan Dimitrijević, Bogoljub Vučković, Radmila Gaćina (2023)
    Geology explorations in KCM runs from 1936. year up to these days and still ongoing. Results in >7,200 drill holes with ≈600,000 m of core drilling and gave lignite ore resources of > 4,1Bt, which 1,15Bt are excavated since 1986. of XIX up to early years of XXI century. For further mining operations in open pits stay 1,5Bt of lignite. Under waste heaps are ≈80 km2, additional 85 km2 should be filled. All of that masses/areas were, are ...

  • Application of stochastic models for mine planning and coal quality control

    Dejan Stevanović, Božo Kolonja, Ranka Stanković, Dinko Knežević, Mirjana Banković (2014)
    ... data variability. Mine production plans, scheduling, and blending strategies require knowledge of the dispersion of relevant geological attributes [8, 14]. Fluctua- tions in mining engineering and geochemical attributes of interest are also relevant for mine de- sign and production scheduling. For example ...
    ... depend on both the quality and quantity of coal mined from each active bench. If it is desired to control the ROM coal quality, the rate of coal production from each active bucket wheel excavator (BWE) should be regulated. The effect of this approach is to blend the coal through the sequence of mining ...
    ... mine. The medium-term planning is concerned with a time span from one to about ten years. It provides information necessary for forecasting future production and cost. There is practical limitation in controlling coal quality during the long and medium-term planning, owing to limited information about ...

  • The application of ArcGIS for assessing the potential of solar energy in urban area: The case of Vranje

    Boban Pavlović, Milica Pešić-Georgiadis (2019)
    In order to determine the solar energy potential for a specified location, it is crucial to consider the latitude, altitude, slope, terrain morphology, atmospheric conditions, etc. Such a complex calculation and mapping of solar energy can be done using the ArcGIS geoprocessing tool, named Area Solar Radiation (ASR). By using the ASR tool, supported with the adequate input data, it is possible to calculate the maximum solar radiation energy (irradiation) for a defined area and for a specified time ...
    Obnovljivi izvori energije, potencijal solarne energije, GIS, mapiranje solarnog potencijala
    ... through photosynthesis. For the purpose of heating and electricity production, the application of solar panels (solar thermal panels for heating: water and PhotoVoltaic (PV) solar panels for electricity 325 production) and the construction of solar thermal power plants is commonly used. ...
    ... biodegradable part of waste (Republic of Serbia, 2013). Total primary energy production from RES in Serbia in 2018 was 2.069 Mtoe (Ministry of Mining and Energy, Republic of Serbia, 2018). In the total domestic production of primary energy from renewable energy sources, the largest share has biomass ...
    ... Climate Change, 9-11 October 2019, Athens - Greece Share in Total Primary Energy Production from Renewables m Biomass m Hydropower m Wind power m Biogas, Solar, Geothermal energy Figure 1: Total production of primary energy from RES in Serbia per energy source (Republic of Serbia, 2018) ...

  • Demise of the Wetterstein Carbonate Platform and onset of the Dachstein Carbonate Platform recorded in deep-water successions of the East Bosnian-Durmitor megaunit (Pliješevina, northern Montenegro, Dinarides)

    Milica Mrdak, Eva Wagerer, Milan Sudar, Nevenka Djerić, Martin Đaković, Hans-Jürgen Gawlick (2024)
    Triassic, Carnica event, clay mineralogy, conodont biostratigraphy, Neo-Tethys

  • Mineralogical analysis of a clay body from Zlakusa, Serbia, used in the manufacture of traditional pottery

    Maja Milošević, Biljana Đorđević, Mihovil Logar (2020)
    калцит, сирова глина, традиционална керамика, Злакуса
    ... Belgrade, Serbia Abstract 'The production of pottery in the traditional manner using local raw materials can provide insights into the provenance of ancient artefacts. This study uses mineralogical analysis to evaluate the raw clays and tempers used for pottery production in Zlakusa (western Serbia). ...
    ... of the pottery, temper, filler, clay body and its provenance with relation to a specific production centre can be performed more accurately through investigation of clay materials used in the production of ceramics (Montana et al., 2011). Raw materials such as clays have various industrial and ...
    ... diagram (Winkler, 1954) indicates that the two samples are not suitable raw materials for the production of bricks (Fig. 7b). The industrial prop- erties of the CIBd sample, in terms of brick production, might be enhanced by adjusting the grain size and content of CC added according to the clay ...

  • The Dictionary of the Serbian Academy: from the Text to the Lexical Database

    Ranka Stanković, Rada Stijović, Duško Vitas, Cvetana Krstev, Olga Sabo (2018)
    In this paper we discuss the project of digitization of the Dictionary of the Serbo-Croatian Standard and Vernacular Language. Scanning and character recognition were a particular challenge, since various non-standard character set encoding was used in the course of the almost 60-year long production of the dictionary. The first aim of the project was to formalize the micro-structure of the dictionary articles in order to parse the digitized text of and transform it into structured data stored in relational lexical database. This approach ...
    computer lexicography, lexical database, language resources, dictionary, Serbian language
    ... formats and into a lexical database with the first aim to speed up the linear production process of the dictionary. This work makes it possible to use the lexical base of the dictionary for research purposes and for the production of various derived lexicographic products. 2 Related Work Digital dictionaries ...
    ... character recognition were a particular challenge, since various non-standard character set encoding was used in the course of the almost 60-year long production of the dictionary. The first aim of the project was to formalize the micro-structure of the dictionary articles in order to parse the digitized ...
    ... but in addition to this it contains accented vocals and various Church Slavonic, Latin and Greek characters. It was first suggested that the production of the dictionary should be modernized many years ago (Sabo & Vitas 1989). However, only in recent years were these ideas revitalized, and various ...

  • The State and Perspective of Belgrade District Heating System Development

    Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Fethi Silajdžić, Samra Arnaut, Goran Đelić (2019)
    District heating (DH) system in Belgrade provides energy for heating of more than 21 million m2 in households (app. 50% of all households), public, commercial and industry sectors. Public Utility Company “Beogradske elektrane” is responsible for all segments of the DH system operation. The system is fueled mostly by natural gas. The share of renewables is negligible. The research analyzes effects of implementation of two main projects proposed in the Development Strategy of the PUC - the introduction of ...
    daljinsko grejanje, Beograd, razvoj
    ... payment based on the measured value, etc.) Although obtained results show different levels of reduction in energy consumption and emission, the production of heat energy remains based on combustion processes. Therefore, some other, non-combustible energy sources should be considered in order to ...

  • Димензионисање система завојних пумпи

    Марија Дивац (2024)
    Овај завршни рад се бави димензионисањем система завојних пумпи (Progressive Cavity Pumps - PCP) које се широко користе у нафтној и гасној индустрији, нарочито за подизање тешких и вискозних флуида. Завојне пумпе су се показале као ефикасно решење у бушотинама са сложеним условима,захваљујући својој способности да транспортују флуиде са високим садржајем чврстих честица и гаса.Рад обухвата анализу кључних параметара као што су вискозност, густина, дубина бушотине и притисак, који су пресудни за избор одговарајуће пумпе.Применом софтверског алата извршена је ...
    завојне пумпе, димензионисање, експлоатација нафте, вискозни флуиди, софтверска симулација, PCP пумпе
    ... – rpaBHranmuoHa KoHcTaHra (9.81 m/s?), 1) — e(-)HKaCHOCT CHCTEMAa. CodQrBepcku anmara 31 mnpopauyH: PumpSizer, CFD camyanuje (Computational Fluid Dynamics) H cnemMjaHMM3OBaHH NIporpaMM 3a HaQTHy HHJIycTpHJy OMoOryhaBajy IIpeH3HO MOJIeJIHpabbe pajia 3aBOJHHX IIyMIIH. OnBH aJlarH KOpHcTe yJHa3He ...
    ... ToMD ID Wall thickness: Roughness " 4 m Y|m Y |mm Y|mm 7 |mm ii 1 |Casing Y Casing 0 809.878 121.3612 9.1694 0.0254 & tEdit'Black Oil' B x FLUID Name: Black Oil Save as template Description: Properties | Viscosity | Calibration | Thermal STOCK TANK PROPERTIES CONTAMINANT MOLE FRACTIONS ...
    ... H raca Kpo3 IeB KaJa Je npucyTHa BoJla. OBa Kopenarnuja y3HMa y 003Hp rycCTHHy, BHCKO3HTCT, IIpHTHCaK H TeMIIepaTyPpy. & Edit Black Oil' B x FLUID Name: - |BlackOil Save as template Description: Properties Viscosity | Calibration | Thermal UNDERSATURATED OIL MIXTURE Correlation: Vasquez ...

  • Eksploatacioni učinci ugljenih sistema na površinskom kopu Tamnava–Zapadno polje

    Marko Lazić, Filip Miletić, Milena Lekić, Veljko Rupar, Željko Petrović, Lazar Žujović (2021)
    U radu su analizirani eksploatacioni učinci ugljenih sistema na površinskom kopu Tamnava–Zapadno polje. Period analize je prvih šest meseci tekuće godine. Analiza je vršena sa aspekta ostvarene proizvodnje, kvaliteta uglja, efektivnog vremena rada, kapacitetnog i vremenskog iskoršćenja i zastoja sistema. Za poređenje podataka različitih parametara koji po svojoj prirodi nisu međusobno uporedivi, u radu su korišćene metode višekriterijumskog odlučivanja.
    proizvodnja uglja, zastoji, metode višekriterijumskog odlučivanja
    ... in the aspect of reached production, coal quality, effective working time, capacity and time utilization and system stoppage using multicriteria decision–making methods. Ključne reči: proizvodnja uglja, zastoji, metode višekriterijumskog odlučivanja Keywords: coal production, stoppage, multicriteria ...

  • Surface functional groups and degree of carbonization of selected chars from different processes and feedstock

    Marija Ilić, Franz-Hubert Haegel, Aleksandar Lolić, Zoran Nedić, Tomislav Tosti, Ivana Sredović Ignjatović, Andreas Linden, Nicolai D. Jablonowski, Heinrich Hartmann (2022)
    The knowledge ofthe structural and chemical properties of biochars is decisive for their application as technical products. For this reason, methods for the characterization of biochars that are generally applicable and allow quality control are highly desired. Several methods that have shown potential in other studies were used to investigate two activated carbons and seven biochars from different processes and feedstock. The chars were chosen to cover a wide range of chemical composition and structural properties as a hardness ...
    Biougalj, različiti procesi dobijanja, različite sirovine, površinski aktivne grupe, x-ray, FT-IR,XPS
    ... bioenergy [8], for the production of a valuable carbonaceous material (biochar) and as a means for carbon sequestration [9,10]. Meanwhile thousands of articles are available on the production, use and modification of biochars as a sustainable carbon source. Two main types of production pro- cesses are ...
    ... wood and bark during bio-oil production. J Colloid Interface Sci., 2007; 310: 57—73. http://dx.doi.org/10.1016/j.jcis.2007.01.020 PMID: 17331527 Tan XF, Liu SB, Liu YG, Gu YL, Zeng GM, Hu XJ, et al. Biochar as potential sustainable precursors for activated carbon production: Multiple applications in ...
    ... gaseous fuels with biochar as a by-product [17], others are optimized for producing designed chars. Biochar is a suitable basic material for the production of activated carbon [18-21]. Some- times it can also favorably substitute activated carbon with no or inexpensive modification due to lower costs ...

  • Belt Weigher Accuracy Limiting Factors

    Aleksandrović Snežana, Jović Mihajlo (2010)