Претрага
111 items
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A Fuzzy Expert Model for Availability Evaluation
Each technical system within itself carries the great potential danger of possible occurrence of failure and damages. Mining machines are characteristic by great investment values, costs of unplanned shutdowns, complex working conditions, and environment and workers hazards. Systematic monitoring of the mining machinery is of great importance for the management of the mining companies. Availability is the overall concept of quality of service. Includes information regard to operating state, an idle state, a standby state and shut down. The ...... carries the great potential danger of possible occurrence of failure and damages. Mining machines are characteristic by great investment values, costs of unplanned shutdowns, complex working conditions, and environment and workers hazards. Systematic monitoring of the mining machinery is of great ...
... evidential reasoning. Reliability Engineering and System Safety, 47(2), 103-118, 1995. [9] Ignjatovic, D., Jovancic, P., Optimization of operation and costs of auxiliary mechanization in order to increase the utilization of overburden and coal systems on the open cast mines of Public Enterprise "Elek ...Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić. "A Fuzzy Expert Model for Availability Evaluation" in Proceedings of the 2019 20th International Carpathian Control Conference (ICCC), AGH University of Science and Technology, Kraków - Wieliczka, Poland (2019)
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Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine
Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić (2021)The production of lignite in large open-pit mines is mainly performed with continuously operating equipment, where bucket-wheel excavators, bucket-chain excavators, belt conveyors, and spreaders are the basic machines. Smaller machines, usually of discontinuous operating nature, are commonly categorized as auxiliary machines. This paper presents the research related to the analysis of auxiliary machine parameters with the case study for a hydraulic excavator. The purpose of the analysis was to develop a model of rating quality of service of the ...Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić. "Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine" in SSRN Electronic Journal, Elsevier BV (2021). https://doi.org/10.2139/ssrn.3945617
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Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry
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 revitalizationSteven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti. "Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry" in SSRN Electronic Journal, Elsevier BV (2021). https://doi.org/10.2139/ssrn.3945979
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Application of VIКOR method in the selection of an optimal splution of excavation “Borska Reka” ore deposit
Sanja Bajić, Dragoljub Bajić, Branko Glušćević, Radmila Gaćina. "Application of VIКOR method in the selection of an optimal splution of excavation “Borska Reka” ore deposit" in 9th International Conference Mining and Environmental protection MEP, 24 – 27 May 2023, Sokobanja, Serbia , Belgrade : University of Belgrade-Faculty of mining and geology (2023)
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Indeksi kontrole održavanja i korišćenja rotornog bagera
Razvoj površinske eksploatacije se u velikom stepenu zasniva na svestranoj mehanizaciji rudarskih radova. Kako bi se zadovoljili potrebni kapaciteti, neophodna je primena savremene mehanizacije, velikih kapaciteta i pouzdanosti u radu. Naime, sa stepenom povećanja mehanizovanosti radova smanjuje se broj zaposlenih radnika, povećava produktivnost rada, smanjuju troškovi po jedinici proizvoda, a samim tim i povećava ekonomičnost površinske eksploatacije. Predmet istraživanja su rotorni bageri SRs 1200 koji predstavljaju samohodne mašine kontinuiranog dejstva namenjene za otkopavanje jalovine i korisne supstance na površinskim ...Jovana Mitrović, Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić, Filip Miletić. "Indeksi kontrole održavanja i korišćenja rotornog bagera" in XI Međunarodna konferencija "Ugalj i kritični minerali 2023", CCM 2023, Zlatibor, 11-14. oktobar 2023., Beograd : Jugoslovenski komitet za površinsku eksploataciju (2023)
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Development of integrated fuzzy model for mine management optimization
Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić (2023)... decision making, Introduction. Mine management optimization, and thus the importance of mining. activity planning, stem from the fact that production costs are measured * Corresponding, author. DOT:10.7546/ CRABS.2023.09.12 1413 in enormous amounts of money. This industry hires a large number of ...
... are largely found at large depths, causing; certain mine management problems that need to be examined. On the one hand, this includes excavation costs, extractable ore reserves, and ore depletion during; the course of mining. On the other hand, a safe mining: technology and a healthy work environment ...Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić. "Development of integrated fuzzy model for mine management optimization" in Comptes rendus de l'Académie Bulgare des Sciences (2023)
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Application of stochastic models for mine planning and coal quality control
... plant must include minimizing: (1) the expected (mean) costs of coal blending and (2) the variance of coal blending costs. The cost objective function includes coal purchasing cost, ash disposal cost, sulfur removal cost, and fuel switch- ing costs. Chance constraints include several risk measures, such ...
... selecting a proper pile size to meet an acceptable level of variability. The optimal size must be defined tak- ing into account capital and operational costs. The key message of stemming from the results in this paper is that the simulation model provides a useful decision support tool to compare opera- ...Dejan Stevanović, Božo Kolonja, Ranka Stanković, Dinko Knežević, Mirjana Banković. "Application of stochastic models for mine planning and coal quality control" in Thermal Science, Belgrade : Vinča Institute of Nuclear Sciences (2014). https://doi.org/10.2298/TSCI130201031S
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Legal framework for recultivation of degraded areas caused by mining exploitation
Radmila Gaćina (2023)Prilikom površinske i podzemne eksploatacije uglja eksploatacioni sistemi oštećuju veće ili manje površine zemljišta. Iskustva pokazuju da su oštećenja zemljišta znatno veća kod površinske eksploatacije, gde je prostora degradiran ne samo u konturi rudnika i okoline, već se promene takođe dešavaju u prirodnom okruženju. U članku su predstavljeni rezultati studije zakonskih okvira rekultivacije u nekim zemljama sveta i u Srbiji. Praktično iskustvo rekultivacije pokazalo je da iskorišćenje i devastacija tokom rudarske aktivnosti predstavljaju opasnost ne samo za pogođena ...... ministry responsible for environmental protection. If liquidation or bankruptcy proceedings are opened against the holder of the exploitation, the costs of rehabilitation and recultivation of the land on which the exploitation was carried out will be covered as a matter of priority from the liquidation ...
... number of problems, especially in the phase of creating and approving project and technical documentation, because it requires more time and higher costs. Consequently, the field of reclamation should be regulated uniformly by the Mining Law, which would avoid unnecessary administration and would ...Radmila Gaćina. "Legal framework for recultivation of degraded areas caused by mining exploitation" in Underground mining engineering, Belgrade : University of Belgrade - Faculty of Mining and Geology (2023). https://doi.org/10.5937/podrad2342027G
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Life Cycle Assessment of Individual Wood Biomass Heating Systems in Households
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 ...... energy consumption of HSs is calculated by using data from the available Energy Agency of the Republic of Serbia’s (AERS) report on the comparative costs of housing heating in the annual report [17]. The AERS’s methodology is based on the analysis of a typical flat of 60 m2 that is heated to 20°C for ...
... ch/site/assets/uploads/2018/05/SYR_AR5_FINAL_full _wcover.pdf (accessed 30 Sep. 2020). [17] AERS, Energy Agency of the Republic of Serbia (2018). Energy costs for heating residential space, AERS, Belgrade. (available only in Serbian)http://aers.rs/g/vesti/file/Dokumenti/grejanje.pdf (accessed 10 Sept. 2020) ...Boban Pavlović, Dejan Ivezić, Marija Živković. "Life Cycle Assessment of Individual Wood Biomass Heating Systems in Households" in 5th International Scientific Conference ”Conference on Mechanical Engineering Technologies and Applications” COMETa2020, East Sarajevo, 2020, University of East Sarajevo, Faculty of Mechanical Engineering East Sarajevo (2020)
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Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements
The capacity of the rotor excavator depends largely on the operation of the subsystem for digging. There is a great contribution to the correct and sharp teeth when the capacity is the highest. In the function of time, the teeth become clogged due to abrasive wear, or changes in their geometric shape. To analyze the bucket wheel drive in depend on wear of the cutting elements in this study adaptive neuro fuzzy inference system (ANFIS) approach was implemented. ANFIS ...Filip Miletić, Predrag D. Jovančić, Milos Milovančević, Dragan Ignjatović. "Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements" in Advances in Engineering Software, Elsevier BV (2020). https://doi.org/10.1016/j.advengsoft.2020.102824
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Cutting Resistance Laboratory Testing Methodology for Underwater Coal Mining
... 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 the bucket wheel and the gearbox. ...
... 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 the bucket wheel and the gearbox. ...
... a large difference in cutting resistance, which was especially manifested in the drop of bucket-wheel excavator productivity, increased maintenance costs, and lower reliability. According to the previous findings, there was a need to rehabilitate the most essential parts of the dredger, bucket wheel ...Vladimir Čebašek, Veljko Rupar, Stevan Đenadić, Filip Miletić. "Cutting Resistance Laboratory Testing Methodology for Underwater Coal Mining" in Minerals, MDPI AG (2021). https://doi.org/10.3390/min11060564
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A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers
Effectiveness evaluation is one of the basic components of engineering asset management and maintenance engineering in general. Effectiveness is an overall concept representing a measurement of quality of service level for the analyzed engineering system. This concept contains a series of partial indicators relating to time in operation and time for maintenance activities, as well as functional properties of the system. This article describes the analysis and structuring of partial indicators, as well as the development of a model ...Miloš Tanasijević, Predrag Jovančić, Dejan Ivezić, Uglješa Bugarić, Radiša Đurić. "A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers" in International Journal of Industrial Engineering: Theory, Applications and Practice (2019)
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Развој модела употребног квалитета помоћне механизације на површинским коповима лигнита
Драгица Јагодић Крунић (2021)Тренутно стање помоћне механизације на површинским коповима лигнита је незадовољавајуће узроковано пре свега старошћу и неблаговременом заменом машима услед чега је расположивост недовољна а трошкови експлоатације и одржавања високи. Тренутно стање и захтеви који се постављају пред ове машине указују на неопходност оптимизације процеса управљања помоћном механизацијом. Одређивање оптималног времена замене и преосталих могућности је најодговорнији управљачки задатак који треба да буде заснован на свеобухватном сагледавању економских, техничких и других узрочно последичних веза. Са економског аспекта гледано треба одржавати ...помоћна механизација, употребни квалитет, ефективност, расположивост, сигурност функционисања, ризик, трошкови животног циклуса, фази логика, Монте Карло метода... власништва (costs of ownership); Co – оперативни трошкови (operational costs), (Cf+Clo+Cpcm); Cf – трошкови погонске енергије (costs of fuel); Clo – трошкови мазива, уља, филтера итд. (costs of lubricants, oils, filters, etc.); Cpcm – трошкови превентивног и корективног одржавања (costs of preventive ...
... где су дате следеће ознаке за трошкове: Cow – трошкови власништва (costs of ownership), Co – оперативни трошкови (operational costs) , Cop – трошкови руковаоца (operator costs); Ct – укупни трошкови (total costs). Трошкови власништва Власник машине, у овом случају рударска ...
... Cgsp – бруто продајна цена (gross selling price) , Cc – трошкови комисије (commission costs) , Cmr – припремни трошкови (make-ready costs) , Ci – трошкови инфлације током периода власништва (inflation costs) , Crv – преостала вредност (residual value) . Вредност коју треба обновити кроз ...Драгица Јагодић Крунић. Развој модела употребног квалитета помоћне механизације на површинским коповима лигнита, Београд : [Д. Јагодић Крунић], 2021
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Mineral Resources of Serbia: Environmental, Societal and Economic Challenges
... determine real costs of medical treatments of illnesses which may potentially be caused by emerging pollutants. Complimentary Contributor Copy 250 Jelena Milić and Tatjana Šolević Knudsen However, these costs are highly underestimated since the real costs need to calculate the costs of a leave ...
... shall bear the total costs of measures for prevention and reduction of pollution, including the costs of risks for the environment and cost of elimination of damage inflicted on the environment. Principle "user pays" – any person who utilizes natural values shall pay real costs for their utilization ...
... Estimated biodiesel production costs in Serbia in 2016 (KUR/L biodiesel) Parameter Type of raw material Soybean Sunflower Oilseed rape Feedstock costs 1.51 0.55 0.78 Amount (kg/L biodiesel) (a) 4.92 2.21 2.46 Price (EKUR/kg) (b) 0.31 0.25 0.32 Total processing costs 0.43 0.25 0.26 Cost of processing ...Vladimir Simić, Rade Jelenković, Dragana Životić. "Mineral Resources of Serbia: Environmental, Societal and Economic Challenges" in Serbia: Current Issues and Challenges in the Areas of Natural Resources, Agriculture and Environment,, Nova Science Publishers, Inc. (2019)
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Effectiveness Analysis of Different Bucket-wheel Excavators
Coal production in open-pit lignite mines in the Republic of Serbia is performed with continuous work systems. In addition to coal production, the same systems are used for the exploitation of large quantities of overburden. According to the reliability concept, continuous systems are in linear connection. If the failure occurs in one part of the system, that will produce a downtime of the entire system. The initial and most important factor of continuous systems is the bucket-wheel excavator. It ...Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić. "Effectiveness Analysis of Different Bucket-wheel Excavators" in 8th International Conference Mining and Environmental Protection, Sokobanja, 22-25 September 2021, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2021)
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Ostvarivanje dobiti pri uvođenju sistema agregatnih zamena na osnovnoj rudarskoj mehanizaciji površinskih kopova EPS
Jedan od osnovnih zadataka na površinskim kopovima uglja je ostvarivanje zadovoljavajućeg vremenskog i kapacitetnog iskorišćenja kontinualnih sistema. Da bi se to postiglo, neophodno je izvršiti izmene u postojećoj strategiji održavanja. Preduslov je uvođenje agregatne zamene vitalnih delova na rudarskim mašinama. Benefiti su višestruki. Očekivani rezultati ovakvog pristupa su: smanjenje zastoja i povećanje vremena rada; direktne materijalne uštede; bolja organizacija rada; racionalizaciju radioničkih i magacinskih kapaciteta; povećanje vrednosti mašina. Da bi se uvela agregatna zamena neophodne su investicije za nabavku ...Predrag Jovančić, Ignjatović Dragan, Đenadić Stevan. "Ostvarivanje dobiti pri uvođenju sistema agregatnih zamena na osnovnoj rudarskoj mehanizaciji površinskih kopova EPS" in X Međunarodna konferencija UGALJ, Zlatibor, Srbija, 13-16. Oktobar 2021., Jugoslovenski komitet za površinsku eksploataciju (2021)
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Integrative GHG Assessment in Oil and Gas Industry
Reducing greenhouse gas emissions is one of the main targets of national strategies in European countries. As a main contributor to emissions, the energy sector is recognized as the most promising to apply measures and actions aimed to decrease GHG emissions. The Oil and Gas industry as a significant contributor to global greenhouse gas emissions is facing a growing need for estimating, mitigating, and reducing the impact of their operations on the atmosphere to stay competitive in a newly ...... as the most complex, requires a detailed GHG emissions model or measurements at facility level. Due to high information requirements and increased costs this approach is rarely chosen. Input data for inventorying emissions from stationary combustion processes are: • Fuel consumption, i.c., data on ...
... emissions at the sourcc location. This approach provides high accuracy on fugitive emissions but requires specialized cquipment and imposes additional costs. • Emission Factors: The cemission factors represent thc empirically derived value of GHG 3released to the atmosphere related to activity levels ...Aleksandar Mirković, Marija Živković, Stevan Đenadić, Darja Lubarda, Chinedu Anyanwa. "Integrative GHG Assessment in Oil and Gas Industry" in Energija, ekonomija, ekologija (2023). https://doi.org/10.46793/EEE23-1.51M
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Underground loading-haulage equipment selection with application of topsis method with different weighting methods of criteria
The choice of adequate mining machines is one of the most complex problems in the underground exploitation of mineral raw materials. The weight of such a decision is reflected in the high prices of these machines and the occurrence of even greater costs during their use if their choice was wrongly conceived. There are numerous examples from practice in which such decisions were made solely on the basis of comparing the prices of machines, without considering any of the ...utovarno-transportna mehanizacija, izbor, TOPSIS, entropija, standardna devijacija, težina kriterijumaVladimir Krivošić, Luka Crnogorac, Rade Tokalić. "Underground loading-haulage equipment selection with application of topsis method with different weighting methods of criteria" in Underground mining engineering, University of Belgrade - Faculty of Mining and Geology (2024)
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Efficiency and lifetime of medium voltage transformers
Snežana Aleksandrović, Vesna Damnjanović. "Efficiency and lifetime of medium voltage transformers" in XVI International Scientific – Professional Symposium, INFOTEH, Jahorina, 22. mart - 24. mart 2017., Istočno Sarajevo : Elektrotehnički fakultet, Univerzitet u Istočnom Sarajevu (2017)
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Fuzzy expert analysis of the severity of mining machinery failure
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 ...Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković. "Fuzzy expert analysis of the severity of mining machinery failure" in Applied Soft Computing, Elsevier BV (2020). https://doi.org/10.1016/j.asoc.2020.106459