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Упит dcterms_subject_txt:Well Performance Optimization

299 items

  • Development of terminological resources for expert knowledge: a case study in mining

    Ljiljana Kolonja, Ranka Stanković, Ivan Obradović, Olivera Kitanović, Aleksandar Cvjetić (2015)

  • Optimizacija dužine strele rotornih bagera u funkciji stabilnosti kosina i efektivnosti rada na površinskim kopovima lignita Srbije

    Branko M. Petrović (2016-07-12)
    Rotorni bageri su mašine koje se u današnje vreme najviše primenjuju uprocesu masovne eksploatacije uglja zahvaljujući, pre svega, nizu tehničkoeksploatacionihprednosti u odnosu na druge vrste bagera. Raznovrsnirudarsko-tehnički zahtevi otkopavanja doprineli su razvoju nekoliko tipova ovihmašina, tako da svaki od njih ima svoje prednosti i nedostatke u odnosu nadrugi tip.Predmet istraživanja u disertaciji odnosi se na izbor optimalnekonstrukcije strele bagera i njene usaglašenosti sa uslovima radne sredine kojiće vladati na površinskim kopovima lignita Srbije, imajući u vidu složene usloveeksploatacije (velika ...
    površinski kop, parametri bloka, kapacitet, rotorni bager, strelabagera, geomehanika, stabilnost kosina, ekonomija
    ... [60.] Tong W. H., Liu G. R..; AN OPTIMIZATION PROCEDURE FOR TRUSS STRUCTURE WITH DISCRETE DESIGN VARIABLES AND DYNAMIC CONSTRAINTS,Computers and Structures, 79, 2(2001) [61.] Tong W.H., Jiang J. S., Liu G. R..; SOLUTION EXISTENCE OF THE OPTIMIZATION PROBLEM OF TRUSS STRUCTURE WITH FREQUENCY ...
    ... strele rotornih bagera u funkciji stabilnosti kosina i efektivnosti rada na površinskim kopovima lignita Srbije;Bucket wheel excavators boom length optimization in function of slopes stability and effectiveness of operation on the Serbian lignite open cast mines Branko M. Petrović Дигитални репозиторијум ...
    ... strele rotornih bagera u funkciji stabilnosti kosina i efektivnosti rada na površinskim kopovima lignita Srbije;Bucket wheel excavators boom length optimization in function of slopes stability and effectiveness of operation on the Serbian lignite open cast mines | Branko M. Petrović | Универзитет у Београду ...

  • Pregled hidrodinamičkih istraživanja bunara sa horizontalnim drenovima numeričkim metodama

    Đorđije Božović, Dušan Polomčić, Dragoljub Bajić (2020)
    U radu je predstavljen pregled odabranih hidrodinamičkih istraživanja realizovanih primenom numeričkih metoda simulacije kretanja podzemnih voda pod uticajem rada bunara sa horizontalnim drenovima. Na osnovu pristupa u matematičkom i hidrauličkom tretiranju, kao i numeričkoj simulaciji bunara sa horizontalnim drenovima na modelima, predstavljeni su najznačajniji aspekti izrade hidrodinamičkih modela ovog kompleksnog tipa vodozahvatnog objekta. Metodologija obuhvata izbor: a) graničnih uslova za simulaciju prirodnih granica, izvora prihranjivanja i dreniranja izdani; b) primenjivanog stepena diskretizacije prostora obuhvaćenog modelom u planu i profilu; ...
    horizontalni bunari, hidraulika bunara, analitički modeli, numerički modeli, hidrodinamičko modeliranje podzemnih voda

  • Models of Determining the Parameters of Rock Mass Oscillation Equation with Experimental and Mass Blastings

    Suzana Lutovac, Branko Gluščević, Rade Tokalić, Jelena Majstorović, Čedomir Beljić (2018)
    ... realized by the Faculty of Mining and Geology in Belgrade. Author Contributions: Suzana Lutovac and Branko Gluščević performed the modelling, optimization and analysis of results. The paper was written by Suzana Lutovac with the support of Rade Tokalić and revised by Čedomir Beljić. Field measurement ...
    ... and felt as shock, i.e., rock mass vibration. Shock or rock mass oscillation can be a consequence of natural processes or human activities (in the performance of mining). Measurements and monitoring of seismic processes can be done in different ways, depending on the cause of the shock [1]. Intensity of ...
    ... characteristics as well as blasting conditions where the explosive amount is given by way of the volume. K is being determined by terrain surveying, Minerals 2018, 8, 70 4 of 18 n—the exponent, conditioned by soil properties and mining conditions and determined by field measurements as well, r—the distance ...

  • Flood protection and water utilization of karst poljes: example of Gatačko Polje, Eastern Herzegovina

    Tina Dašić, Ljiljana Vasić (2020)
    Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry,Global and Planetary Change

  • Optimizacija parametara reza rotornog bagera pri otkopavanju materijala sa povećanom čvrstoćom

    Saša D. Bošković (2016-09-09)
    Otkopavanje materijala rotornim bagerom je veoma sloţen fiziĉko-mehaniĉki proces. Pokazatelji efektivnosti tog procesa zavise od velikog broja raznovrsnih ĉinilaca od kojih se posebno mogu istaći: fiziĉko-mehaniĉke karakteristike materijala koji se otkopava, reţim rada bagera i izbor tehnoloških parametara bloka, odreska i reza, geometrije vedrica i zuba itd. Poseban problem se javlja kod otkopavanja materijala povećane ĉvrstoće, što je ĉest sluĉaj na našim površinskim kopovima. Dimenzionisanje specifiĉne sile kopanja bagera prema manjim masama izuzetno ĉvrstog materijala je neracionalno i rešenje ...
    rotorni bager, parametri reza, otpor na kopanje, dinamika bagera, kapacitet, optimizacija, specifična potrošnja energije
    ... Измењено: 2023-10-14 03:59:19 Optimizacija parametara reza rotornog bagera pri otkopavanju materijala sa povećanom čvrstoćom;Optimization of bucket wheel excavator cutting parameters at mining of materials with increased strength Saša D. Bošković Дигитални репозиторијум Рудар ...
    ... ког факултета Универзитета у Београду [ДР РГФ] Optimizacija parametara reza rotornog bagera pri otkopavanju materijala sa povećanom čvrstoćom;Optimization of bucket wheel excavator cutting parameters at mining of materials with increased strength | Saša D. Bošković | Универзитет у Београду | 2016-09-09 ...
    ... Bеоgrаd, 2016. U N I V E R S I T Y O F B E L G R A D E FACULTY OF MINING AND GEOLOGY Saša D. Bošković OPTIMIZATION OF BUCKET WHEEL EXCAVATOR CUTTING PARAMETERS AT MINING OF MATERIALS WITH INCREASED STRENGTH Doctoral Dissertation ...

  • Application of Gel for Water Shutoff: A Case Study of Kelebija Oil Field

    Irina Zahirovic, Petar Skrobonja, Dušan Danilović (2022)
    This paper focuses on the results of water shutoff operations using DSGA polymer gel in the Kelebija oil field. The methodology of candidate wells selection and the manner of performing the operation will also be included. The Kelebija oil field is characterized by a complex reservoir system with heterogeneous layers of different permeability and dual porosity, which led to the early breakthrough of water. For the last 25 years, average water cut was above 90%. Implementation of water shutoff ...
    intervención de pozos petroleros, reservoir characterization, production control, well logging, downhole intervention, enhanced recovery, complex reservoir, reservoir surveillance, water shut-off, upstream oil & gas

  • 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
    ... small towns in Serbia named after famous Serbian poets and politicians: Aleksa Šantić, Svetozar Miletić, Jaša Tomić. Table 6. Strategy rules performance data for subsets: N (initial DELAC nouns), A (initial DELAC adjectives), CN (additional common nouns), T (additional toponyms) N A CN T 1. Items ...
    ... CIAA. (2009) 237–240 6. Krstev, C., Stanković, R., Vitas, D., Obradović, I.: The Usage of Various Lexical Resources and Tools to Improve the Performance of Web Search Engines. In: 6th LREC, Marrakech, Marocco (2008) 7. Jacquemin, C.: Spotting and Discovering Terms through Natural Language Pro- cessing ...
    ... ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Automatic Construction of a Morphological Dictionary of Multi-Word ...

  • Availability as a dimension of energy security in the Republic of Serbia

    Boban Pavlović, Dejan Ivezić (2016)
    There is a range of modern approaches and models in literature for the evaluation and determination of energy security, which are based on different parameters and indicators. For most of them, a common characteristic is emphasizing the avail ability of energy, as an important dimension for ensuring energy security. In this paper, concise overview of Serbian energy sectors is given and appropriate energy indicators are defined and determined. Selected indicators provide insight into the main components that characterize availability ...
    raspoloživost energije, energetski indikatori, energetska bezbednost
    ... process (AHP) methodology is proposed and implemented for analysis of obtained indicators, their interactions and specific importance to availability performance. The proposed procedure for availability indicator determination and their evaluation by AHP is implemented for deter- mination of availability ...
    ... energy resource supply in a sustainable and timely manner with the energy price being at a level that will not adversely affect the eco- nomic performance of the economy. Thus, there are several factors that can influence the energy security [7]: – the availability of reserves, both indigenously ...
    ... aspects is the best way to achieve the objective of improving values of the presented indicators. Each well-weighed investments in education, building of new energy infrastructure and facilities, as well as improvement of existing one, can only bring benefits in terms of security and quality of life ...

  • Development and Evaluation of Three Named Entity Recognition Systems for Serbian - The Case of Personal Names

    Branislava Šandrih, Cvetana Krstev, Ranka Stanković (2019)
    In this paper we present a rule- and lexicon-based system for the recognition of Named Entities (NE) in Serbian news paper texts that was used to prepare a gold standard annotated with personal names. It was further used to prepare training sets for four different levels of annota tion, which were further used to train two Named Entity Recognition (NER) sys tems: Stanford and spaCy. All obtained models, together with a rule- and lexicon based system were evaluated on ...
    NER, Named Entity Recognition Systems, Serbian, Personal Names
    ... OLD test set and in Figure 2 for the DANAS-GOLD test set the mutual relationship be- tween three NER system remains the same. We also compared performance of all three NER systems by each named entity type (Fig- ure 3). Results for all three models distinguishing entity types show that all three systems ...
    ... 2015) there is approximately one feminine name per 7 seven masculine names) and confirmed in our training sets (Table 4). 1066 We compared the performance of SRPNER with its previously reported results. In (Krstev et al., 2005) results for the recognition of personal names were P = 0.97, R = 0.86, F1 ...
    ... ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Proceedings of Recent Advances in Natural Language Processing ...

  • The Fuzzy–AHP Synthesis Model for Energy Security Assessment of the Serbian Natural Gas Sector

    Aleksandar R. Madžarević, Dejan D. Ivezić, Miloš L. Tanasijević, Marija A. Živković (2020)
    Natural gas is used for the production of almost 20% of total energy today. The natural gas security of the Republic of Serbia is an urgent strategic, political and security issue. Serbia is one of the most vulnerable countries in Southeast Europe, because it only has one supply route. This study is a contribution to efforts to better understand the factors affecting energy security through the implementation of a new methodology based on the fuzzy–AHP synthesis model for measuring ...
    energetska bezbednost, prirodni gas, fazi AHP, AHP višekriterijumska analiza, fazi teorija
    ... economic and demographic development as input parameters, to assess supply and demand of energy up until 2050 [35]. ERIS is a multi-regional bottom-up optimization model with technology learning that researches global trends in supply up until 2100 [36]. According to [37] there is also a combination of these ...
    ... review of energy security [29], energy security index developed by the EU Center for Joint Research in Italy [30] and the global energy architecture performance index, proposed by the World Economy forum [31]. Multi-criteria analyses are another tool used to support decision-making [32–34]. These kinds of ...
    ... as the degree of confidence that Mi belongs to that linguistic expression of energy security. The final expression of identified energy security performance is: Mi = {(βi = 1, “very low”), (βi = 2, “low”), (βi = 3, “modern”), (βi = 4, “high”), (βi = 5, “exceptional”)} (21) In another defuzzification ...

  • Дигиталне библиотеке у рударству и геологији са посебним освртом на представљање сиве литературе

    Биљана Лазић, Александра Томашевић, Михаило Шкорић (2019)
    Имајући у виду потребу за проналажењем информација похрањених у различитим облицима документације која се генерише у областима рударства и геологије на Рударско-геолошком факултету Универзитета у Београду, отпочет је процес развоја дигиталне библиотеке ROmeka@RGF, на платформи за приказивање дигиталних колекција - Омека. Значајан део документације представља такозвана сива литература која је претежно заступљена у виду вишетомне документацијe. Први савладани изазов представљало је повезивање различитих вишетомних делова пројектних извештаја у једну целину која би била лако доступна и претражива.
    дигиталне библиотеке, сива литература, Омека, језички ресурси, речници
    ... Gruyter, 2010. 1-9. Krstev, Cvetana, Ranka Stanković, Duško Vitas, Ivan Obradović. “The Usage of Various Lexical Resources and Tools to Improve the Performance of Web Search Engines”. Sixth International Conference on Language Resources and Evaluation (LREC ‘08), Marrakech, Morocco. Nicoletta Calzolari ...
    ... ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs 149 БИБЛИОИНФО MA Биљана Лазић1 Др Александра Томашевић2 ...

  • Business Models for Small-scale Biomass Projects Development

    Dejan Ivezić, Miodrag Gluščević, Marija Živković (2019)
    Biomass is recognized as the most promising renewable energy source in Serbia. The share of biomass in Serbian final energy consumption is over 10%, but mostly related to traditional use in stoves and ovens. One of the main obstacles for wider implementation of contemporary biomass facilities is the inexperience of consumers and stakeholders in the implementation of “innovative” business models, especially in the cases of small-scale projects. In this paper, three different business models (public utility company, energy cooperative ...
    ... 1,120 kW at the boiler fringes. The capacity of the two new biomass boilers is planned with 500 kW and 200 kW (due to load management and cost optimization reasons), whereas the capacity of one of the two existing heavy fuel oil boilers accounts for further 750 kW (for peak load and back-up purposes) ...
    ... individually or jointly in a cooperative or other legal entity, should not have preferential treatment in the public procurement procedure. However, it is well known that transport costs have significant share in the price of biomass, and from that point of view, local biomass producers would be in a better ...
    ... model means association of Kostojevići’s citizens in energy cooperative. Energy cooperative could be an initiator, investor and project implementer, as well as biomass supplier and biomass plant operator. The scheme of functioning of this business model is shown in Figure 1. This concept is widely implemented ...

  • An Approach to Management Decision Support: The Coal Mine Pljevlja Management Information System

    Božo Kolonja, Ranka Stanković, Filip Vuković, Ivan Obradović (2006)
    In this paper we describe the approach that has been used in the development of the Management Information System (MIS) in the Coal Mine Pljevlja in Montenegro. The methodology of this approach was based on new information technologies and management techniques which have already been successfully applied in other related fields. Its main goal was to introduce modern management techniques to mining, adapted to specific features of the mining industry, its operations and environment, thus enabling the tactical management ...
    ... better strategic as well as operative decision making possibilities, cooperation with business partners based on the Web, insight into great possibilities allowed by scenarios of strategic decision making, etc. Speaking of the time needed to make an efficient decision, optimization of the process ...
    ... ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs An Approach to Management Decision Support: The Coal Mine Pljevlja ...
    ... system of information, thus motivating the mining management, especially on the tactical level, to initiate enhancements of production processes, as well as the development of more complex components of management. The first results showed that considerable reduction of transportation costs are possible ...

  • Старење бунара у алувијалним срединама различитог степена оксичности

    Brankica Majkić (2013-09-27)
    Старење бунара настаје као последица процеса корозије и колмирања. Процесекорозије могуће је спречити уградњом филтерских конструкција од материјалаотпорних на корозију. Колмирање може да настане без обзира на врсту материјалаод кога се праве бунарске конструкције, а процесом може бити захваћенаприфилтарска зона па и зона саме водоносне средине. Из тог разлога тезa јеусмеренa на процесе који доводе до колмирања бунара и последицe опадањaкапацитета водозахватних објеката. Полазна хипотеза је да бунари стареразличитом брзином у срединама различитог степена оксичности. Хидрохемијскеи микробиолошке карактеристике подземних ...
    старење бунара, алувијалне издани, степен оксичности средине,колмирање, бунарски талог, локални хидраулички губитак, дозвољене улазнебрзине
    ... and its implications for well and piezometer performance, Impact of Human Activity on Groundwater Dynamics (Proceedings of a symposium held during the Sixth IAHS Scientific Assembly at Maastricht, The Netherlands, July 2001). IAHS Publ. no. 269, 2001. pp 297-230. 153. Houben, G. (2003). Iron oxide ...
    ... to construct the well casing and the process may extend to the immediate vicinity of the well screen and even affect the aquifer itself. For the above reason, focus of the thesis is on the processes that lead to well clogging and the impact of such processes on declining well capacity. The starting ...
    ... doctoral dissertation  WATER WELL AGEING IN ALLUVIAL SEDIMENTS OF DIFFERENT OXIC CONDITIONS SUMMARY Water well ageing is generally a consequence of corrosion and clogging. Corrosion can be prevented by installing well casings made from materials resistant to corrosion ...

  • Influence of Initial Treatment on the Survival and Recurrence in Patients With Differentiated Thyroid Microcarcinoma

    Jasna Mihailović, Ljubomir Stefanović, Ranka Stanković (2013)
    ... (P = 0.0001, P = 0.0005, and P = 0.02, respectively). Sex, histopathological type of the tumor, metastases at presentation, initial treatment, performance of radioactive ther- apy, and risk categories had no influence on survival (P = 0.8, P = 0.6, P = 0.1, P = 0.4, P = 0.5, and P = 0.1, respectively) ...
    ... 0001, P = 0.0005, and P = 0.02, respectively). Sex, histopathological type of the tumor, metastases at presentation, type of the initial treatment, performance of radioactive therapy, and risk categories had no influence on sur- vival (P = 0.8, P = 0.6, P = 0.1, P = 0.4, P = 0.5, and P = 0.1, respectively) ...
    ... ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Influence of Initial Treatment on the Survival and Recurrence ...

  • Mineral Resources of Serbia: Environmental, Societal and Economic Challenges

    Vladimir Simić, Rade Jelenković, Dragana Životić (2019)
    ... 2014) Estimation of the performance of homogeneous and heterogeneous Ba(OH)-or biodiesel production Ba(OH)> as solution and solid Sunflower oil Methanol to oil molar ratio 6:1, catalyst to oil ratio 5-10 wt%, 60% (Kostić et al. 2018) Kinetic modelling and optimization of transesterification ...
    ... protein source in formulated rations for cattle, sheep and goats as well as chickens and pigs. Feeding trials with both swine and poultry have shown that triticale can replace corn in diets with little effect on animal performance. A second area of interest for triticale is use of the straw for ...
    ... (Stamenković et al. Optimization by response surface methodology and kinetic | KOH Hempseed oil Methanol to oil molar ratio 6.5:1, 2015) modelling of transesterification and characterization of the optimal catalyst to oil ratio 1.2 wt%, 43"C produced biodiesel (Rajković et al. Optimization by response ...

  • Energetska efikasnost elektromotora na površinskim kopovima

    Snežana Aleksandrović, Ilija Jeftenić (2023)

  • A multi-criteria approach for assessing the potential of renewable energy sources for electricity generation: Case Serbia

    Boban Pavlović, Dejan Ivezić, Marija Živković (2021)
    When assessing the potential of renewable energy alternatives for electricity generation, it is necessary to implement a multi-perspective approach that includes economic, technical, environmental, and socio-political criteria. For the evaluation of criteria and alternatives, the Fuzzy Analytical Hierarchy Process (FAHP) method is applied. The obtained weights are formed according to the values of energy indicators and expert judgments. The use of a fuzzy numerical value scale for the assessment of expert judgments and energy indicators provides a more sensitive ...
    Proizvodnja električne energije, Obnovljivi izvori energije, Višekriterijumsko odlučivanje, Srbija
    ... used as an indicator (Table 5). In this context, the technical potential is defined as achievable energy generation from RES for the given system performance, topographic, en- vironmental, and land-use constraints (NRE, 2020). Additional characteristics of RES facility operation such as efficiency, flexi- ...
    ... 20Acquiring%20the%20Status%20of%20PPP%20SG%208-13.pdf. IPCC (Intergovernmental Panel on Climate Change), 2014. Anex III, technology- specific cost and performance parameters, cambridge. available at: https: //www.ipcc.ch/site/assets/uploads/2018/02/ipcc_wg3_ar5_annex-iii.pdf. AEBIOM (European Biomass Association) ...
    ... potential, geospatial data science. available at: https://www.nrel.gov/gis/re- potential.html. Energy Community, 2020. Serbia’s 2020 implementation performance and key energy sector benchmark data. available at: https://www.energy- community.org/dam/jcr:486fedf4-ed5f-4e3f-b995-5d5829b471f1/EnC_ IR2020_Serbia ...

  • 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
    ... GDP growth or total employment. Instead, they observed zero to modest positive effects, suggesting that carbon taxes may not delay economic performance while contributing to emissions reductions. Wu and Gong (2021) estimate the impact on China's GDP by analyzing different allocation modes in ...
    ... paper aims to expand academic debate in understanding the potential impacts of environmental policies (particularly climate change) on economic performance, among which the ETS is unques- tionably included. The impact of introducing the ETS was methodo- logically applied through an approach for assessing ...
    ... Dechezlepretre, A., Nachtigall, D., Venmans, F., 2023. The joint impact of the European Union emissions trading system on carbon emissions and economic performance. J. Environ. Econ. Manag. 118, 102758. https://doi.org/10.1016/j. jeem.2022.102758. Dong, Z., Xiao, Y., 2024. Carbon emissions trading policy ...