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Упит dcterms_subject_txt:Well Performance Optimization

299 items

  • 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

  • Model za optimizaciju graničnog saržaja metala u rudi u funkciji dugoročnog planiranja površinskih kopova

    Daniel P. Kržanović (2016-06-14)
    Optimizacija graničnog sadržaja metala u rudi jedan je od osnovnih koraka u planiranju i dizajniranju površinskih kopova i ima za cilj postizanje maksimalne neto sadašnje vrednosti (NPV). Iz tog razloga, optimizacija graničnog sadržaja i danas je predmet mnogih istraživanja u rudarskoj nauci, sa ciljem rešavanja praktičnih problema u eksploataciji ležišta.Dugoročno planiranje eksploatacije na površinskim kopovima podrazumeva sagledavanje svih relevantih parametara i faktora (geologije rudnog ležišta, tehnologije proizvodnog procesa, kapaciteta otkopavanja i prerade, troškova, cena metala, iskorišćenja i dr) kako ...
    površinski kop, dugoročno planiranje, optimizacija graničnog sadržaja, maksimizacija neto sadašnje vrednosti (NPV).
    ... 519.863/.87:553.9 622.271:622.33(043.3) MODEL FOR THE CUT OFF GRADE OPTIMIZATION IN THE FUNCTION OF LONG-TERM PLANNING OF THE OPEN PITS ABSTRACT Optimization the cut off grade of metal in the ore is one of the basic steps in planning and design of the open ...
    ... methods and optimization algorithms, which are used today in the modern software tools, it is possible to manage the production costs and revenues or economy of operation. With the same aim of this doctoral dissertation, the integrated mathematical model has been developed for optimization the cut ...
    ... W.A., Dimitrakopoulos R., 2013, A Heuristic Approach to Stochastic Cutoff Grade Optimization for Open Pit Mining Complexes, Les Cahiers du GERAD G-2013-55, pp 1-12. Asad, M.W.A., 2005a, Cut-off grade optimization algorithm with stockpiling option for open pit mining operations of two economic ...

  • 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 ...

  • Simulation of Hydrogeological Environmental Discharge in Case of Interruption Constant Observations

    Marina Čokorilo Ilić, Dragoljub Bajić, Miroslav Popović (2024)
    Monitoring Network, data, hydrogeological environment, tunnel, simulation

  • Analysis and visualization of geophysical well-logging data from closely spaced boreholes

    Branislav Sretković, Ivana Vasiljević, Dimitry Sidorov - Biryukov (2024)
    Geophysical logging measurements for determining the condition of the rock mass on the dam profile and locating the predisposed directions of water circulation and loss from the reservoir were conducted in four boreholes distributed at a close distance. The survey was carried out in a typical karst terrain, which is an additional challenge for defining the geological model, especially in terms of water retention. That kind of data set provides an excellent opportunity for a new approach to analysis ...
    well-logging in karst, water loss, data correlation, data fusion
    ... visualization of geophysical well-logging data from closely spaced boreholes Branislav Sretković, Ivana Vasiljević, Dimitry Sidorov - Biryukov Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Analysis and visualization of geophysical well-logging data from closely ...
    ... 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 TToceéno u30anue na Geologica Macedonica, N0.6 MAKE OHCKO ...
    ... econosaare Ha PenyOnka CeBepHa MakcJuoHuja Fifth Congress of Geologists of the Republic of North Macedonia ANALYSIS AND VISUALIZATION OF GEOPHYSICAL WELL- LOGGING DATA FROM CLOSELY SPACED BOREHOLES IBranislav Sretković, !'Iyvana Vasiljević, IDimitry Sidorov - Biryukov 1University of Belgrade - Faculty ...

  • Non-Detonating Chemical Mixture for Non-Invasive Methods of Rock Breaking

    Lazar Kričak, Milanka Negovanović, Nikola Simić, Stefan Milanović (2024)
    Within the Innovation developed several different non-detonating chemical mixtures for non-invasive methods of rock breaking. Laboratory and polygon tests gave the satisfactory results and knowledge enough to start the practical experiments in the field. The basis of this innovation is a theoretical assumption that certain chemical mixtures release a large quantity of gases during combustion. If these gases are found in the enclosed space a growing pressure on the walls of the chamber in which combustion takes place will ...
    non-detonating, chemical mixture, rock breaking, borehole pressure

  • Development of A Business Intelligence Tool For Accident Analysis in Mines

    Ljiljana Kolonja, Ranka Stanković, Ivan Obradović, Olivera Kitanović, Uroš Pantelić (2015)
    ... to these assets, where knowledge assets represent the knowledge this organization possesses or needs to acquire in order to improve its performance. Within knowledge processes, knowledge generation comprises of knowledge acquisition, where external knowledge is elicited from the environment to ...
    ... mining) that allows researchers and other users to browse content tagged with subject terms from their taxonomy. Besides improving their performance using ICT, companies within Serbian mining industry are also striving towards advancing collaboration with their business partners’ networks both ...
    ... ICT support is needed not only within intra-business processes, but also within inter- enterprise business processes, in order to secure better performance and interoperability in business networks (Albani & Dietz, 2006). The concepts of enterprise ontology and reusable knowledge assets are essential ...

  • Blasting mats for the protection of people, structures and the environment in proximity to the blast site

    Milanka Negovanović, Lazar Kričak, Stefan Milanović, Jovan Marković, Nikola Simić, Snežana Ignjatović (2023)
    Енергија експлозије која се ослобађа током процеса детонације минских пуњења у бушотинама користи се за дробљење чврсте стенске масе на комаде различитих облика и величина, у зависности од карактеристика стене и оптимизације параметара бушења и минирања. Поред позитивних ефеката минирања, постоје и одређени нежељени ефекти сваког процеса минирања који се могу јавити, а то су: потреси тла, разлетање комада одминираног материјала, ваздушни удари, загушљиви и отровни гасови и прашина. Разлетање комада је неконтролисано избацивање комада одминиране стенске масе и ...
    mecevi za miniranje, pokrivanje, razletanje komada, miniranje

  • Application of geophysical and multispectral imagery data for predictive mapping of a complex geo-tectonic unit: a case study of the East Vardar Ophiolite Zone, North-Macedonia

    Filip Arnaut, Dragana Đurić, Uroš Đurić, Mileva Samardžić-Petrović, Igor Peshevski (2024)
    General Earth and Planetary Sciences
    ... Carranza 2023). The min- eral prospectivity mapping studies conducted in the Philip- pines demonstrated that the RF model exhibited superior performance compared to other models in predicting the presence of gold deposits (Carranza and Laborte 20154a). This was also observed in cases where there ...
    ... method for determin- ing the optimal range of the number of trees (n”T) for an algorithm, is to run a certain (user-defined) number of model performance tests with sequentially increasing n”T, until the Out-of-bag (OOB) error stops decreasing and stabilizes at a near value. The number of trees ...
    ... evaluation metrics and the predictive maps of ophiolites. Figure 6 presents a set of ten evaluation metrics that have been chosen to assess the performance of the model across various training data sets and different numbers of trees in the RF model. Regarding accuracy, the models that employed ...

  • Assessments of effects of implementation of strategic plans for development of Belgrade District heating system

    Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Miodrag Grujić (2020)
    The district heating system (DHS) is one of the key elements of the Belgrade energy system. Overview of the current state and basic characteristics of the DHS are presented in this paper. The focus is on the planned development of DHS and on the analyses of effects of realization of measures and projects defined by strategic documents related to DHS which are adopted by city authorities (Development Strategy of DHS and Strategy of Belgrade Development). Two exploratory scenarios were ...
    Daljinsko grejanje, LEAP, Primarni energetski faktor, Uvozna zavisnost, CO2 emisija

  • An Approach to Development of Bilingual Lexical Resources

    Stanković Ranka, Obradović Ivan, Trtovac Aleksandra (2012)
    ... tune with Bibliša’s specifics would substantially contribute to its performance. Hence, Biblimir was born. 3.1 The Logical Model The logical model of Biblimir, with its characteristic classes, their attributes, as well as relations among the classes is depicted in Figure 1 in the form of an ...
    ... Sciences. The aim of the new resource, Biblimir, is to help overcome the shortcomings of existing bilingual resources and hence improve the performance of Bibliša. Categories and Subject Descriptors H.3.7 [Information Storage and Retrieval]: Digital Libraries – Collection General Terms ...
    ... As we have already mentioned, the available wordnets and the Dictionary of Librarianship were not sufficiently developed to secure optimal performance of the system. Although it might have seemed that a solution of this problem should be looked for in the refinement of these resources, we opted ...

  • Advancing Sentiment Analysis in Serbian Literature: A Zero and Few-Shot Learning Approach Using the Mistral Model

    Milica Ikonić Nešić, Saša Petalinkar, Mihailo Škorić, Ranka Stanković, Biljana Rujević (2024)
    Ova studija predstavlja analizu sentimenta srpskih starih romana iz perioda 1840-1920, koristeći veliki jezički model (LLM) Mistral za tehniku učenja sa zasnovani na takozvanim "zero" i "few-shot" pokušajima. Glavni pristup uvodi inovacije osmišljavanjem istraživačkih upita (promptova) uključuju tekst sa uputstvom za klasifikaciju bez primera i na osnovu nekoliko primera, omogućavajući jezičkom modelu da klasifikuje osećanja u pozitivne, negativne ili objektivne kategorije. Ova metodologija ima za cilj da pojednostavi analizu osećanja ograničavanjem odgovora, čime se povećava preciznost ...
    zero-shot, few-shot, sentiment, Serbian, Mistral model

  • A business intelligence approach to mine safety management

    Ljiljana Kolonja, Ranka Stanković, Ivan Obradović, Olivera Kitanović, Dejan Stevanović, Marija Radojičić (2016)
    ... gov/niosh-mining) that allows researchers and other users to browse content tagged with subject terms from their taxonomy. Besides improving their performance using ICT, companies within Serbian mining industry are also striving towards advancing collaboration with their business partners’ networks both ...
    ... support is aimed not only at improving intra-business processes, but also at inter-enterprise business processes, in order to secure better performance and interoperability in business networks [11]. The concepts of enterprise ontology and reusable knowledge assets are essential for knowledge ...
    ... Online analytical processing in mine safety 3.1. Methodology for data management Safety management relies on job standards, rules, regulations, performance evaluations, and policies, which are used within the chain of command to secure that employees fulfill their assigned responsibilities satisfactorily ...

  • 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

  • Analiza primene višekriterijumskih metoda u optimizaciji izbora hidruličnih bagera na površinskim kopovima uglja

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Filip Miletić, Ivan Janković (2019)
    Hidraulični bageri primenjuju se u različitim oblastima privrede a najzastupljeniji su u građevinarstvu i rudarstvu. Na površinskim kopovima sa kontinualnim sistemima, klasifikuju kao pomoćna mehanizacija a na površinskim kopovima sa diskontinualnim sistemima, kao osnovna mehanizacija. Kako je u oba slučaja njihova primena neizostavna, važno je izvršiti adekvatnu analizu postojećih podataka, u cilju optimizacije izbora tipa hidrauličnog bagera u odnosu na uslove rada datog površinskog kopa. U radu su opisane različite višekriterijumske metode koje su korišćene za analizu hidrauličnih bagera. ...
    višekriterijumske metode, površinski kop uglja, pomoćna mehanizacija, hidraulični bager
    ... potential of multi-criteria optimization methods that are used in the analysis of hydraulic excavators. Different multi-criteria methods used for the analysis of hydraulic excavators are described. All advantages and disadvantages of these methods are presented, as well as the quality of output ...
    ... Preference by Similarity to Ideal Solution [10], Ching-Lai Hwang  VIKOR - VIseKriterijumska Optimizacija i Kom- promisno Resenje (Multicriteria Optimization and Compromise Solution) [11], S. Opricovic  ELECTRE (I, II, III, IV) - franc. ELimination Et Choix Traduisant la Realité (ELimination and ...
    ... organization method for enrichment evaluation), TOPSIS (Technique for Order of Prefe- rence by Similarity to Ideal Solution), VIKOR (Multi- criteria Optimization and Compromise Solution) i ELECTRE (ELimination and Choice Expressing RE- ality). Navedene višekriterijumske metode pružaju mogućnost upoređivanja ...

  • Cutting Resistance Laboratory Testing Methodology for Underwater Coal Mining

    Vladimir Čebašek, Veljko Rupar, Stevan Đenadić, Filip Miletić (2021)
    Geology,Geotechnical Engineering and Engineering Geology
    ... I” for underwater coal mining with bucket-wheel type UCW-450 has been in operation for over 20 years. Based on analyzing the bucket-wheel dredger performance, productivity, maintenance costs, and reliability, a rational decision was made: to rehabilitate the most essential parts of the dredge, including ...
    ... ly, a sufficient digging force must be available at the digging wheel [2]. Digging conditions strongly influence the excavator productivity and performance [3]. The digging force, F, has three components (tangential, lateral, and forward thrust) [4–7], perpendicular to each other (Figure 1). The tangential ...
    ... I” for underwater coal mining with bucket-wheel type UCW-450 has been in operation for over 20 years. Based on analyzing the bucket-wheel dredger performance, productivity, maintenance costs, and reliability, a rational decision was made: to rehabilitate the most essential parts of the dredge, including ...

  • Određivanje zbijenosti starog komunalnog otpada

    Jovana Janković, Dragoslav Rakić, Irena Basarić Ikodinović, Tina Đurić (2021)
    Bez obzira na savremene tretmane komunalnog otpada u svetu, u Srbiji je i dalje najčešći vid odlaganja na komunalne deponije, pa zbijanje otpada predstavlja jednu od ključnih faza formiranja deponije. Na ovaj način znatno se smanjuje zapremina otpada, ubrzava proces degradacije i produžava radni vek deponije. Zbog toga su geotehničke karakteristike komunalnog otpada prilikom zbijanja, veoma bitne kako u fazi projektovanja tako i u fazi izgradnje deponije i optimizacije prostora. Tu se pre svega misli na maksimalnu suvu zapreminsku ...
    komunalni otpad, deponija, Proktorov opit, optimalna vlažnost, maksimalna suva zapreminska težina

  • Comprehensive Profiling of Microbiologically Induced CaCO3 Precipitation by Ureolytic Bacillus Isolates from Alkaline Soils

    Olja Šovljanski, Lato Pezo, Jovana Stanojev, Branimir Bajac, Sabina Kovač, Elvira Tóth, Ivan Ristić, Ana Tomić, Aleksandra Ranitović, Dragoljub Cvetković, Siniša Markov (2021)
    MICP process, kinetic study, calcite, vaterite, MALDI-TOF identification, Bacillus licheniformis, Sporosarcina pasteurii
    ... agar, as well as colour changes, were checked after 7 days at 30 ◦C, while inorganic depositing on solid media with calcium ions was observed by light microscope (Zeiss Primo Star Binocular Microscope, Jena, Germany). Based on standard score results, bacterial isolates with the best performance based on ...
    ... ureolytic activity [2]. Therefore, kinetic pathways of ureolytic activity have been used to better understanding the MICP process based on predictions, optimization, and description of the kinetic parameters [10]. Although the kinetic study can vary widely between bacterial species [3], the activity of high ...
    ... Tailor Made Concr. Struct. 2008, 1, 425–430. 27. Omoregie, A.I.; Khoshdelnezamiha, G.; Seniana, N.; Ek Leong Ongb, D.; Nissoma, P.M. Experimental optimization of various cultural conditions on urease activity for isolated Sporosarcina pasteurii strains and evaluation of their biocement potentials. Ecol ...

  • 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