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Упит dcterms_subject_txt:Well Performance Optimization

292 items

  • A Knowledge-Based Approach to Mine Ventilation Planning in Yugoslav Mining Practice

    Nikola Lilić, Ivan Obradović, Ranka Stanković (2002)
    Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full understanding and use of the obtained results require the involvement of an experienced specialist in the ventilation field. The solution was found in the creation of a hybrid system INVENTS, whose knowledge base represents a formalization of the expert knowledge in the mine ventilation field. In this paper, we ...
    ... complex structure composed from several integrated software packages: ResNet, SimVent and VENTEX (Fig. 3). These packages integrate both well known nu- merical optimization and various artificial intelligence methods, which allow for an M in . R es . E n g . 2 0 0 2 .1 1 :3 6 1 -3 8 2 . D o w ...
    ... I. S. Lowndes and B. Denby, Genetic algorithm optimization of large UK coal mine ventilation network, Proc. 8th US Mine Ventilation Symp., 1998, 625-632. 13. Z. Y. Yang, I. S. Lowndes and B. Denby, Application of genetic algorithms to the optimization of large mine ventilation networks, Trans. Instn ...
    ... and that alternative solutions are needed. To that end, a genetic algorithm was used. Binary sequences for two variables were created for the optimization of the ventilation network by means of a genetic algorithm. The variable representing the pressure of the booster fan varies in wide limits of ...

  • Optimisation of underground mine decline development system using genetic algorithm

    Zoran Gligorić, Aleksandar Ganić, Rade Tokalić, Aleksandar Milutinović (2014)
    ... terminals are: mineral processing facility, surface breakout point and ore body access points. Brazil et al. created a software tool called Decline Optimization Toll (DOT). The heuristic methods used in DOT1 are replaced in the new version of the software tool, DOT2, by a method based on an understanding ...
    ... population, replacing the parent chromosomes in which they were derived from, producing a new generation. This cycle is performed until the optimization criterion is met (Shopova and Vaklieva-Banacheva, 2006). A typical genetic algorithm has the following structure: Optimisation of underground ...
    ... ; Tokalić R.; Milutinović A. REFERENCES 1 ALI, F.A. (2014) A novel hybrid genetic differential evolution algorithm for constrained optimization problems. International Journal of Advanced Computer Science and Applications, 3 (6), pp.6-12. 2 BRAZIL, M. et al. (2003) Optimising Declines ...

  • Uticaj geološke neizvesnosti u razvoju rudarskih projekata

    Petar Marković, Dejan Stevanović, Mirjana Banković (2023)
    Rudarstvo je industrija koja se nosi sa različitim vrstama neizvesnosti i rizika zbog svoje prirode i specifičnosti. Neizvesnost u rudarstvu može poticati iz različitih izvora i uticati na različite aspekte rudarskih projekata. Kao jedan od dominantnih faktora, ističe se geološka neizvesnost. Geološka neizvesnost igra ključnu ulogu u rudarstvu i može značajno uticati na procenu resursa i rezervi, planiranje eksploatacije, ekonomsku isplativost i upravljanje rizicima. Ova neizvesnost se ne može eliminisati, ali se uz primenu adekvatnih standarda i zakona može ...
    ... foreign practice from the aspect of categorization of resources and reserves, as well as the influence of the degree of reliability of the geological characteristics of the deposit on the results of the pit optimization, are shown. The analysis was carried out on an iron ore deposit and is based on ...
    ... Goodfellow R., Dimitrakopoulos R. (2016). Global optimization of open pit mining complexes with uncertainty. Applied Soft Computing , 40, 292-304. [11] Kolonja B., Stevanović D., Pešić-Georgiadis M., Banković M., Kolonja Lj. (2015). Uncertainty in pit optimization. Mining and Enviromental protection. Vrdnik ...
    ... in the ore (grade of iron in the ore). The results were generated in the Whittle software package. Keywords: geological uncertainty, risk, pit optimization, planning 1. Uvod Savremeno rudarstvo izloženo je stalnom trendu pogoršanja uslova poslovanja. Mogućnost ostvarenja ekonomskih i drugih ciljeva ...

  • Uticaj ekstremnih procesa na rizike površinske eksploatacije

    Natalija Pavlović, Tomislav Šubaranović, Dragan Ignjatović (2022)
    Nepredvidivi ekološki negativni slučajni procesi mogu uticati na geo-tehnički sistem pri površinskoj eksploataciji ležišta mineralnih sirovina, što u velikoj meri uvećava rizike i ugrožava realizaciju proizvodnje. Kvantitativna analiza sa proračunom verovatnoća pojava ovakvih ekstremnih događaja i procenom odgovarajućih ekonomskih posledica, posebno u uslovima globalnih klimatskih promena, omogućava definisanje rizika i optimizaciju parametara sistema površinske eksploatacije.

  • Keyword Extraction from Parallel Abstracts of Scientific Publications

    Slobodan Beliga, Olivera Kitanović, Ranka Stanković, Sanda Martinčić-Ipšić (2017)
    ... explore the performance on the shorter texts [8]. The achieved results suggest that SBKE can be applied to shorter documents as well. Since SBKE is grounded in a structural and statistical information incor- porated into the network structure the expected outcome is to achieve better performance on larger ...
    ... represented as a complex network. The constructed parallel corpus of scientific abstracts with annotated keywords allows a better comparison of the performance of the method across languages since we have the con- trolled experimental environment and data. The achieved keyword extrac- tion results measured ...
    ... tools [10]. In other words, more sophisticated keyword extraction methods in the text preprocessing step usually use some heuristics to gain in performance by using semantic or syntactic knowledge. As the source of syntactic knowledge, methods usually use part-of-speech tags (POS) in order to restrict ...

  • Uticaj utiskivanja gas-lift gasa na prenos mase i toplote

    Branko Grubač (2019)
    Nakon uvođenja kontinualnog gas-lifta, primećen je porast proizvodnje tečnog naftnog gasa, TNG, u postrojenju za preradu gasa, kao jednog od finalnih proizvoda dobijenog iz fluida gaso kondenzatnih i rastvorenog gasa iz naftnih bušotina. Pretpostavljeno je da se prisustvom gas-lift gasa uspostavlja drugačija ravnoteža faza u odnosu na slučaj bez gaslifta, te da je gas-lift gas stripovao propan i butane iz tečne u parnu fazu, što je dovelo do povećanja prinosa TNG-a. Napravljen je model bušotine koja radi u kontinualnom gas-liftu ...
    gas-lift, modelovanje bušotine, prenos mase i toplote, taloženje parafina
    ... Dynamic flow performance modeling of a gas-lift valve, Society of petroleum engineers, SPE Latin American and Caribbean Petroleum Engineering Conference, Buenog Aires, str 1-11, (2001) [44] X. Zhao, J. Xu, Numerical simulation of temperature and pressure distribution in producing gas well, World journal ...
    ... Khamehchi, A novel approach to the gas-lift allocation optimization problem, Petroleum Science and Technology, Vol. 29, str 418-427, (2011) [50] E. Componogara, R. Nakashima, Applying dynamic programming to a gas - lift optimization problem, Proceeding of the 2nd Brazilian Conference on research ...
    ... Wellbore heat-transfer modeling and applications, Journal of Petroleum science and engineering, str 179-185, (2012) [41] C. Kabir, A Hasan, Performance of a two-phase gas/liquid flow model in vertical wells, Journal of Petroleum Science and Engineering, Vol. 4, str 273-289, (1990) Doktorska ...

  • Using Query Expansion for Cross-Lingual Mathematical Terminology Extraction

    Velislava Stoykova, Ranka Stanković (2018)

  • Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining

    Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović (2019)
    Analitički hijererhijski proces (AHP), dozeri, eksploatacija uglja, površinski kopovi
    ... REality (ELECTRE) [5], Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) [6], Fuzzy logic (FUZZY) [7], Multiple-criteria Optimization and the Compromise Solution (VIKOR) [8]. In this paper, in order to define optimal evaluating methodology, the AHP method was chosen as the most ...
    ... REality (ELECTRE) [5], Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) [6], Fuzzy logic (FUZZY) [7], Multiple-criteria Optimization and the Compromise Solution (VIKOR) [8]. In this paper, in order to define optimal evaluating methodology, the AHP method was chosen as the most ...
    ... 3.1. Tehnical Parameters (TP) As far as the first criterion is concerned, the technical parameters of the considered equipment characterize the performance of the machine defined by the manufacturers of the equipment. Those were actually parameters which characterized the possibilities of the functioning ...

  • 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

  • Human reliability assessment approaches and their use in mining

    Panić Biljana, Vujošević Mirko, Milutinović Aleksandar (2012)

  • Numerical Modeling and Simulation of the Effectiveness of Groundwater Source Protection Management Plans: Riverbank Filtration Case Study in Serbia

    Dušan Polomčić, Dragoljub Bajić, Bojan Hajdin, Dragan Pamučar (2022)
    The paper describes the establishment and testing of an algorithm for developing sustainable management plans associated with groundwater source protection against potential pollutants and discusses the effectiveness of individual systems. The applied methodology pertains to groundwater resource management, particularly those cases that involve riverbank filtration. Namely, groundwater (numerical) modeling is employed to examine the groundwater regime and balance, as well as to create protection systems and illustrate their effectiveness. Particle tracking analysis is used to study pollutants’ travel and ...
    Water Science and Technology,Aquatic Science,Geography, Planning and Development,Biochemistry

  • Integrating landslide magnitude in the susceptibility assessment of the City of Doboj, using machine learning and heuristic approach

    Cvjetko Sandić, Miloš Marjanović, Biljana Abolmasov, Radislav Tošić (2023)
    In this work, landslide assessment of the Doboj City area was modeled by combining machine learning and heuristic tools. The machine learning part was used to map the Morphometric factor. i.e. probability of landslides based on relation between the magnitude of events and morphometric parameters: elevation, distance to streams, slope, profile curvature, and aspect. The Random Forest and Support Vector Machines algorithms were implemented in the learning protocol, which included several strategies: balancing of the training/testing set size, algorithm ...
    podložnost na kliženje, magnituda klizišta, mašinsko učenje, heuristički pristup, Doboj

  • The Usage of Various Lexical Resources and Tools to Improve the Performance of Web Search Engines

    Krstev Cvetana, Stanković Ranka, Vitas Duško, Obradović Ivan (2008)
    In this paper we present how resources and tools developed within the Human Language Technology Group at the University of Belgrade can be used for tuning queries before submitting them to a web search engine. We argue that the selection of words chosen for a query, which are of paramount importance for the quality of results obtained by the query, can be substantially improved by using various lexical resources, such as morphological dictionaries and wordnets. These dictionaries enable semantic ...
    LR web services, MultiWord Expressions & Collocations, Information Extraction, Information Retrieval
    ... 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 The Usage of Various Lexical Resources and Tools to Improve the Performance of Web Search Engines Cvetana Krstev 1 , Ranka Stanković2 , Duško ...
    ... Tools to Improve the Performance of Web Search Engines Krstev Cvetana, Stanković Ranka, Vitas Duško, Obradović Ivan Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] The Usage of Various Lexical Resources and Tools to Improve the Performance of Web Search Engines ...
    ... when searching for strasna nedelja ‘Passion Week’ the unrelated results for strašna nedelja ‘horrible week’ or ‘horrible Sunday’ are obtained as well. 2. Typical problems when retrieving documents using a web search engine 1. In general, when the concept the query relates to is lexicalized ...

  • Određivanje prostorne distribucije vrednosti hidrauličkih parametara izdani: primer površinskog kopa „Radljevo“

    Dragoljub Bajić, Dušan Polomčić, Jelena Ratković, Predrag Pajić (2019)
    Najčešće se kalibracija hidrodinamičkih modela vršila manuelno - „probanjem“ sa različitim vrednostima hidrauličkih parametara i hidrauličkih karakteristika graničnih uslova. Ovakav način rada zahteva veliko znanje i iskustvo eksperta, pri čemu ostaje otvoreno pitanje da li dobijeno rešenje ima optimalan skup parametara. Primenom optimizacione metode, koja se zasniva na Gauss-Marquardt-Levenberg-ovom algoritmu, i PEST softvera, ...
    kalibracija hidrodinamičkog modela, PEST, koeficijent filtracije

  • Primary crusher site selection in open pit mines - case study in Sungun copper mine

    Ali Nasirinezhad, Dejan Stevanović, Dragan Ignjatović, Mehdi Rahmanpou (2021)
    Facility site selection, (such as Primary or in pit Crusher location) is one of the most important steps in mine de-sign process that has a significant impact on economy of the mining operation. This study covers an attempt to find the optimal location forprimary crusher in order to support the expansion of Sungun copper mine, which is the second largest open pit mine in Iran. Recent exploration drilling has led to a considerable increase in the ore reserve. Therefore, ...
    odabir lokacije, višekriterijumsko odlučivanje, analiza osetljivosti, Sungun rudnik bakra

  • Challenges in using wastewater heat pumps in district heating systems

    Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović, Dimitrije Manić (2022)
    Decarbonization of district heating systems requires ensuring significant amounts of renewable energy available in the proximity of the district heating network. One of the promising solutions is the utilization of purified water from wastewater treatment plants by heat pumps. However, as a heat source, wastewater treatment plants are characterized by annual variability of the flow and temperature of purified water. The consequence is the variability of recoverable heat potential. In this paper, the effect of variability is analyzed for ...
    Toplotna pumpa, Daljinsko grejanje, Postrojenje za prečišćavanje otpadnih voda

  • Negative Impact of Backwater Levels of Danube River and its Tributaries to the Groundwater Regime in Meliorated Riverside Areas

    Predrag Pajić, Uroš Urošević, Dušan Polomčić, Milan Dimkić (2016)
    This paper describes updated calculation methodology of Danube backwater impact, occurred as a consequence of “Đerdap I” hydropower plant operation, onto the meliorated riverside areas. This methodology is based on hydrodynamic analysis of groundwater regime (size, duration, level and inflow changes) and quantification of melioration areas impairment which is caused by “Đerdap I” hydropower plant operation. By comparing the groundwater regime elements, obtained by variant hydrodynamic calculation in mathematical models for natural – not backed up and actual – ...
    HPP ''Djerdap 1'', backwater influence, groundwater regime, hydrodynamic analysis, melioration area, drainage system, additional energy engagement

  • 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

  • Life Cycle Assessment of Individual Wood Biomass Heating Systems in Households

    Boban Pavlović, Dejan Ivezić, Marija Živković (2020)
    The use of solid fuels (wood biomass and coal) for heating of households continues to be common practice within European countries. Solid fuel combustion in households contributes more than 46% to total emissions of fine particulate matter. In this study, a life-cycle assessment (LCA) of firewood-based and pellet-based heating systems is performed. These two systems represent two different types of individual wood biomass heating systems. In the case of the firewood-based heating systems, it is analyzed a typical stove ...
    Grejanje, Analiza životnog ciklusa, Drvna biomasa, Individualni sistemi grejanja
    ... and in the case of pellet-based, a modern wood pellet-based furnace is analyzed. The objective of the LCA study is to assess the environmental performance of heating systems using GWP index, expressed through CO2-eq emissions. According to the results, wood pellet furnace could reduce emissions by ...
    ... wood pellet-based furnace, very popular in the recent period, are analyzed. The main objective of this LCA study is to assess the environmental performance of two HSs based on wood biomass installed in Serbia using the global warming potential (GWP) index. The study also aims to identify the LC phases ...
    ... focused on [11]:  Minimizing harmful effects on the environment caused by its activities,  Achieving continual improvement of its environmental performance. Boban Pavlović, Dejan Ivezić. Marija Živković 430 However, since LCA considers the environmental aspects and the potential impacts of ...

  • State and perspective of individual household heating in Serbia: A survey-based study

    Boban Pavlović, Dejan Ivezić, Marija Živković (2021)
    This paper presents the results of the household survey on individual household heating systems in Serbia. The survey was conducted in the period October to December 2020 with the participation of 1100 households with individual household heating systems. The information collected in the questionnaire can be separated into three main parts: basic household data, current heating system characteristics, and households’ perceptions and attitudes. The survey results provide unique and comprehensive information concerning individual household heating systems and the main ...
    Domaćinstva, Individualni sistemi grejanja, Korišćenje energije, Stavovi potrošača, Anketa, Srbija