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Упит dcterms_subject_txt:General Engineering

593 items

  • 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 ...

  • Size–strain line-broadening analysis of anatase/brookite (TiO<sub>2</sub>)-based nanocomposites with carbon (C): XRPD and Raman spectroscopic analysis

    Aleksandar Kremenović, Mirjana Grujić-Brojčin, Nataša Tomić, Vladimir Lazović, Danica Bajuk-Bogdanović, Jugoslav Krstić, Maja Šćepanović (2022)
    A size-strain line-broadening analysis of the XRPD patterns and Raman spectra for two anatase/brookite (TiO2)-based nanocomposites with carbon (C) was carried out and the results compared with those of a similar sample free of carbon. The crystal structures and microstructures of anatase and brookite, as well as their relative abundance ratio, have been refined from XRPD data by the Rietveld method (the low amount of carbon is neglected). The XRPD size-strain analysis resulted in reliable structure and microstructure results ...
    Materials Chemistry, Metals and Alloys, Atomic and Molecular Physics, Optics, Electronic, Optical and Magnetic Materials

  • Development and Application of Methodology for Quantification of Overbreaks in Hard Rock Tunnel Construction

    Zoran Berisavljević, Dragoljub Bajić, Vojkan Jovičić (2023)
    A methodology for determining overbreaks in hard rock tunnel construction using the drill-and-blast technique is presented in this paper. The methodology was developed for and applied to crystalline medium- to thick-bedded limestone, but it can be used in any jointed hard rock mass. Overbreaks are inevitable in hard rock tunnelling in a low-confinement environment (shallow tunnels up to several hundred meters deep) as a result of wedge failures along unfavourably oriented discontinuities caused by blasting. It is widely accepted ...
    hard rock, drill-and-blast, geological overbreak, technological overbreak, stability criterion, discontinuity orientation, tunnel construction

  • Strategic Environmental Assessment in the Application of Preventive Protection for Wind Farm Noise—Case Study: Maestrale Ring Wind Farm

    Boško D. Josimović, Aleksandar Cvjetić, Božidar Manić (2021)
    Determining the spatial position of wind turbines is the initial and most important phase in the development of a wind farm project. In this sensitive phase, all potential problems that may arise in the later stages of project development should be prevented by means of spatial and urban planning instruments. This makes it possible to achieve maximum use of the potential of wind in a particular space and, thus, fulfil the technical and economic requirements of the project while ...
    Energija,energetski inženjering i elektroenergetska tehnologija,obnovljivi izvori energije, održivost i životna sredina,električni i elektronski inženjering,kontrola i optimizacija,inženjering
    ... obtained. Bearing in mind that the general approach to impact assessment in the SEA process in methodological terms is predominantly expert, qualitative and subjective, but also flex- ible in relation to various precise models and tools used in environmental engineering and other areas based on scientific ...
    ... infrasound and low frequency noise generated by wind turbines, the main effects of their impact on humans are physical symptoms, health effects in general and affective influence (mood). However, their literature analysis also showed the absence of any results from systematic and comprehensive clinical ...
    ... 1: Calculation of the absorption of sound by the atmosphere; ISO 9613-2:1996 Acoustics—Attenuation of sound during propagation outdoors—Part 2: General method of calculation;In- ternational Organization for Standardization: Geneva, Switzerland, 1993. 60. Farboud, A.; Crunkhorn, R.; Trinidade, A ...

  • Assessing Criteria Weights by the Symmetry Point of Criterion (Novel SPC Method) - Application in the Efficiency Evaluation of the Mineral Deposit Multi-Criteria Partitioning Algorithm

    Zoran Gligorić, Miloš Gligorić, Igor Miljanović, Suzana Lutovac, Aleksandar Milutinović (2023)
    Information about the relative importance of each criterion or the weights of criteria can have a significant influence on the ultimate rank of alternatives. Accordingly, assessing the weights of criteria is a very important task in solving multi-criteria decision-making problems. Three methods are commonly used for assessing the weights of criteria: objective, subjective, and integrated methods. In this study, an objective approach is proposed to assess the weights of criteria, called SPC method (Symmetry Point of Criterion). This point ...
    Вишекритеријумско одлучивање, тежине критеријума, тачка симетрије критеријума, налазиште минерала, алгоритам, процена учинка

  • Human factor risk management procedures applied in the case of open pit mine

    Snežana Kirin, Aleksandar Sedmak, Wei Li, Miodrag Brzaković, Igor Miljanović, Ana Petrović, Simon Sedmak (2021)
    Risk management aims to provide a controlled work environment to ensure the safe operation of the high-risk systems. It is a dynamic process which work in a continual state of change. The issue of human factor risk and rules and regulations in open pit mine is a main focus of this paper in order to develop predictive models of behavior of workers in relation to compliance with the procedures and rules. Presented survey was conducted in open pit coal ...
    Upravljanje rizikom, ljudski faktor, bager sa kašikom, metod konačnih elemenata

  • Managing mining project documentation using human language technology

    Aleksandra Tomašević, Ranka Stanković, Miloš Utvić, Ivan Obradović, Božo Kolonja (2018)
    Purpose: This paper aims to develop a system, which would enable efficient management and exploitation of documentation in electronic form, related to mining projects, with information retrieval and information extraction (IE) features, using various language resources and natural language processing. Design/methodology/approach: The system is designed to integrate textual, lexical, semantic and terminological resources, enabling advanced document search and extraction of information. These resources are integrated with a set of Web services and applications, for different user profiles and use-cases. Findings: The ...
    Digital libraries, Information retrieval, Data mining, Human language technologies, Project documentation

  • 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 ...

  • Failure Estimation of the Majdanpek Open Pit East Face Based on Inverse Velocity Model

    Miloš Marjanović, Stefan Milanović, Nikola Simić, Lazar Kričak (2024)
    The Majdanpek open pit mine south district is currently active mining prospect of copper ore exploitation in eastern Serbia. Its depth is approaching the termination depth and occurrences of large-scale instabilities and global instability of the final pit slope is possible. These can generate catastrophic mass movement inside an area that encloses a regional road route and the Pek River bed which is channelled along the outer contour of the pit. The displacements that were noted in early 2023, in the ...
    displacement, survey, inverse velocity, open pit

  • Overview of the hydrogeological investigations of recently discovered world class deposits in Serbia

    Nebojša Atanacković, Vladimir Živanović, Veselin Dragišić, Sava Magazinović (2019)
    Europe industry has growing concerns on availability of the raw materials. To address this challenge, the European Commission has created a list of critical raw materials for the EU, launched EIT Raw Materials initiative, and continuously support research projects (like INTRAW, UNEXMIN etc.) with the aim of reducing the dependency and meeting growing demands. In the last 15 years Serbia is experiencing new bust in geological exploration of mineral deposits. Currently 167 exploration licenses are active, covering approximately 6000 ...
    Groundwater, Raw materials, Lithium, Mining, Field hydrogeology

  • Classifying large strains from digital imagery: application to analogue models of lithosphere deformation

    Taco Broerse, Nemanja Krstekanić, Cor Kasbergen, Ernst Willingshofer (2021)
    ... digital imagery: application to analogue models of lithosphere deformation | Taco Broerse, Nemanja Krstekanić, Cor Kasbergen, Ernst Willingshofer | EGU General Assembly 2021, Vienna, Austria, 19.-30.4.2021. | 2021 | | http://dr.rgf.bg.ac.rs/s/repo/item/0005604 Дигитални репозиторијум Рударско-геолошког факултета ...
    ... publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs EGU21-6046 EGU General Assembly 2021© Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. Classifying large strains from digital ...
    ... (d.b.t.broerse@uu.nl) 2Department of Regional Geology, Faculty of Mining and Geology, University of Belgrade, Belgrade, Serbia 3Faculty of Civil Engineering and Geosciences, Delft University of Technology, Delft, The Netherlands We are interested in reconstructing the time evolution of 2D plane deformation ...

  • Examination of the possibility of obtaining pyrite concentrate from the flotation tailings of the Lece mine

    Predrag Lazić, Đurica Nikšić, Dejan Stojanović, Tamara Stojanović (2022)
    Рудник Леце је карактеристичан по томе што у флотацијским концентратима олова и цинка као корисну примену има злато и сребро. Практично од отварања рудника и флотације трају истраживања и борба за што боље технолошке показатеље на сва четири платива метала (олово, цинк, злато и сребро) посебно на злату. Овај рад представља допринос тој борби у циљу повећања искоришћења злата. Како је начин појављивања злата веома различит (самородно, са оловом и цинком, са пиритом и кварцом) то је и технолошка ...
    Флотација Леце, концентрат пирита, злато, сребро

  • Determining the Impact of Cutting Elements State on the Bucket–Wheel Excavator Vibration and Energy Consumption

    Filip Miletić, Predrag Jovančić, Miloš Milovančević, Miloš Tanasijević, Stevan Đenadić (2022)
    Background There are two types of specifc sizes’ measurements. The frst is the measurement of energy consumption in a working technological process, and the second is the measurement of vibration, which is displayed over amplitudes of speed. There is an interplay between these two processes. Increasing the power consumption, the value of the vibration speed amplitudes increases. Purpose The process of the determination of machining parameters was based on minimizing the power consumption and vibration of the cutting tool, ...
    merenje, potrošnja energije, vibracije, radni vek reznog elementa

  • Knowledge and Rule-Based Diacritic Restoration in Serbian

    Cvetana Krstev, Ranka Stanković, Duško Vitas (2018)
    In this paper we present a procedure for the restoration of diacritics in Serbian texts written using the degraded Latin alphabet. The procedure relies on the comprehensive lexical resources for Serbian: the morphological electronic dictionaries, the Corpus of Contemporary Serbian and local grammars. Dictionaries are used to identify possible candidates for the restoration, while the dataobtainedfromSrpKorandlocalgrammarsassistsinmakingadecisionbetween several candidates in cases of ambiguity. The evaluation results reveal that,dependingonthetext,accuracyrangesfrom95.03%to99.36%,whilethe precision (average 98.93%) is always higher than the recall (average 94.94%).
    diacritic restoration, morphological dictionary, corpus, word n-grams, local grammars
    ... , Benjamins, V. R., and Fensel, D. (1998). Knowledge engineering: principles and methods. Data & knowledge engineering, 25(1-2):161–197. Veale, T. and Hao, Y. (2008). A context-sensitive framework for lexical ontologies. The Knowledge Engineering Review, 23(1):101–115. Wilks, Y. (2009). Ontotherapy ...
    ... current processing. The quality of disambiguation for RuThes is much lower than for domain-specific thesauri because of the presence of ambiguous general words; • Grouping semantically related concepts into so-called thematic nodes. This provides better deter- mination of concept weights, which are ...
    ... G. (2011). Ontological foundations for conceptual part-whole relations: the case of collectives and their parts. In Advanced Information Systems Engineering, pages 138–153. Springer. Koeva, S. (2010). Bulgarian wordnet–current state, applications and prospects. Bulgarian-American Dialogues, pages 120–132 ...

  • Flotability of chalcopyrite from the Rudnik deposit

    Đurica Nikšić, Predrag Lazić, Milena Kostović (2021)
    Директно селективно флотирање олова, бакра и цинка у флотацији рудника „Рудник” датира од 1984. године. Технолошка шема омогућава директно издвајање селективних концентрата у три циклуса. У првом циклусу се издваја минерал олова (галенит), док су минерал бакра (халкопирит) и минерал цинка (марматит) депримирани. У другом циклусу се оток концентрације минерала олова кондиционира и припрема за издвајање минерала бакра. Након кондиционирања, у овом циклусу се издваја минерал бакра. У трећем циклусу се оток концентрације минерала бакра кондиционира и припрема за ...
    Директно селективно флотирање, халкопирит, KAX, NaCN

  • Application of the VIKOR Method for Selecting the Purpose of Recultivated Terrain after the End of Coal Mining

    Radmila Gaćina, Sanja Bajić, Bojan Dimitrijević, Tomislav Šubaranović, Čedomir Beljić, Dragoljub Bajić (2024)
    reclamation, coal, sustainable development, multi-criteria decision making, VIKOR method

  • 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
    ... metalurgija, Savez inžinjera i tehničara Srbije, Beograd, Vol. 71, 2, str 209-214, (2016) [5] L. Lake, Petroleum engineering handbook, Vol. 4, Production operations engineering, Society of petroleum engineers, Texas, str 1-38, (2007) [6] J. Lea, H. Nickens, M Wells, Gas well deliquification, ...
    ... Fundamentals of gas-lift engineering, Well design and troubleshooting, Elsevier, Cambridge, str 81-106, (2016) [8] S. Ayatollahi, M. Narimani, M. Moshfeghian, Intermittent gas-lift in Aghajari oil field, a mathematical study, Journal of Petroleum Science and Engineering, Vol. 42, Issues 2-4, str ...
    ... Equilibrium constants from a modified Redlich-Kwong equation of state, Chemical Engineering Science, Vol. 27, str 1197-1203, (1972) [35] D. Peng, D. Robinson, A new two-constant equation of state, Idustrial & Engineering Chemistry Fundamentals, Vol. 15, str 56-64, (1976) [36] T. Boldizsar, The d ...

  • 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
    ... g the general advantages and disadvantages of each method. By developing technologies in the petroleum production, the limits of the applicability of artificial lift methods are constantly moving, which affects the conditions for their application. The theory of fuzzy sets and, in general, fuzzy ...
    ... on criteria are well utilization and service ability. Fuzzy logic has a great application, used in many engineering disciplines as a decision-making tool. In the field of petroleum engineering it is applied in several areas: Reservoir Porosity Estimation [2,3]; Oil Separation [4]; Hydraulic fracturing ...
    ... Simple Additive Weighting—SAW and VišeKriterijumska Optimizacija i Kompromisno Rešenje—VIKOR), have also been applied. In practice, there is no general model and standard for the selection of artificial lift methods, but each oil company uses an expert system, i.e., programs, or tables with defined ...

  • Fuzzy expert analysis of the severity of mining machinery failure

    Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković (2020)
    Mining machinery failure is almost an everyday occurrence. Usually the failures bare certain consequences, which require additional financial costs to repair and restore the system to its operational state. The consequences are viewed through negative and damaging effects a failure has on the machine, health and safety of the employees, work environment, and on the environment. The removal of the consequences of the failure requires additional financial investment, which has a negative impact on the company’s business. In order ...
    Severity of failure, Severity of failure assessment, Mining machinery, Fuzzy sets, Fuzzy logic

  • Моделирање утицаја одступања линије најмањех отпора од пројектоване на интензитет потреса од минирања

    Стефан Милановић (2024)
    Према дефиницији линија најмањег отпора представља најкраће растојање од центра минског пуњења до слободне површине. Oвим истраживањем представљен је утицај линије најмањег отпора, као и њеног одступања од пројектоване на интезитет потреса услед минирања. Проблем линије најмањег отпора је веома заступљен у пракси, где се занемарује изглед слободне површине, који може бити врло неправилан. Линију најмањег отпора је потребно мерити целом дужином минске бушотине према слободној површини, иако је у пракси случај да се мери најчешће као растојање од ...
    линија најмањег отпора, 3D модел, потреси услед минирања, минирање, слободна површина, метода раздвојених елемената