Претрага
823 items
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Model upravljanja investicionim projektima otvaranja površinskih kopova uglja
Cvjetko P. Stojanović (2015-04-27)Brze promene u okruženju pred rukovodioce postavljaju mnogobrojne zahteve,pre svega, one koji se tiču ostvarenja ciljeva u zadatom vremenu i raspoloživimsredstvima što zahteva fleksibilan pristup u organizovanju aktivnosti i efikasnost unjihovom sprovođenju.Upravljanje projektima, bilo koje vrste, suštinski, predstavlja veoma složenproces odlučivanja uslovljen velikim brojem ulaznih faktora. Ti faktori treba daomoguće fokusiranje na prioritete i ciljeve, praćenje realizacije, fleksibilnost uprevazilaženju teškoća, prilagođavanje promenama, te kontrolu nad ostvarenimrezultatima. Ovakav način upravljanja zahteva korišćenje proverenih tehnika i alata tetimski rad angažovanih na ...Cvjetko P. Stojanović. "Model upravljanja investicionim projektima otvaranja površinskih kopova uglja" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2015-04-27)
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Debris-flow Susceptibility Assessment in Flow-R: Ribnica River Case Study
Debris flows are among the most dangerous erosional geohazards due to the fast rate of movement and long runout zones. Even though the initiation can be triggered in mountainous areas, inhabited and with steep slopes, their propagation and deposition can endanger not only buildings and infrastructure in the urbanized areas, but also threaten human lives. As these initiation areas usually represent unattainable terrains with rapid vegetation cover development, field observations and aerial photo analysis become high-demanding tasks. Consequently, medium-to-regional ...Ksenija Micić, Miloš Marjanović, Biljana Abolmasov . "Debris-flow Susceptibility Assessment in Flow-R: Ribnica River Case Study" in Proceeding of the 6th Regional Symposium on Landslides in the Adriatic-Balkan Region, ReSyLAB 2024, University of Belgrade, Faculty of Mining and Geology (2024). https://doi.org/https://doi.org/10.18485/resylab.2024.6
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Risk Evaluation: Brief Review and Innovation Model Based on Fuzzy Logic and MCDM
Stevan Djenadic, Milos Tanasijevic, Predrag Jovancic, Dragan Ignjatovic, Dejan Petrovic, Ugljesa Bugaric (2022)The risk assessment of engineering systems represents an important part of the quality of service and dependability. The existing methods for risk evaluation use crisp sets for rating partial indicators’ proposition and their cumulative products as an overall indicator. In this paper, existing FMEA and FMECA methods have been improved using the fuzzy expert system for calculating the risk priority number. The application of fuzzy logic allows the use of linguistic descriptions for risk analysis. In this way, the ...Stevan Djenadic, Milos Tanasijevic, Predrag Jovancic, Dragan Ignjatovic, Dejan Petrovic, Ugljesa Bugaric. "Risk Evaluation: Brief Review and Innovation Model Based on Fuzzy Logic and MCDM" in Mathematics, MDPI AG (2022). https://doi.org/10.3390/math10050811
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Determining the Availability of Continuous Systems at Open Pits Applying Fuzzy Logic
This work presents a model for determining the availability of continuous systems at open pits by applying fuzzy logic and fuzzy inference systems. The applied model was formed by the synthesis of independent partial indicators of availability. The model is based on an expert system for assessing the availability of continuous mining systems. The availability of the system, as a complex state parameter, is decomposed into the partial indicators, reliability, and convenience of maintenance, and the fuzzy compositions, used ...системи, континуални систем експоатације, површински коп, рударство, расположивост, фази логика, max–min композиција, min–max композицијаMiljan Gomilanović, Miloš Tanasijević, Saša Stepanović. "Determining the Availability of Continuous Systems at Open Pits Applying Fuzzy Logic" in Energies, MDPI AG (2022). https://doi.org/10.3390/en15186786
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Fragmenting of cylindrical rock specimens under explosive load: Comparison between model and laboratory results
Slavko Torbica, Veljko Lapcevic (2016)Slavko Torbica, Veljko Lapcevic. "Fragmenting of cylindrical rock specimens under explosive load: Comparison between model and laboratory results" in Mining and Metallurgy Engineering Bor (2016). https://doi.org/10.5937/mmeb1601103T
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Applying the Fuzzy Inference Model in Maintenance Centered to Safety: Case Study – Bucket Wheel Excavator
Predrag Jovančić, Miloš Tanasijević, Vladimir Milisavljević, Aleksandar Cvjetić, Dejan Ivezić, Uglješa Bugarić (2020)Predrag Jovančić, Miloš Tanasijević, Vladimir Milisavljević, Aleksandar Cvjetić, Dejan Ivezić, Uglješa Bugarić. "Applying the Fuzzy Inference Model in Maintenance Centered to Safety: Case Study – Bucket Wheel Excavator" in Applications and Challenges of Maintenance and Safety Engineering in Industry 4.0 , Pennsylvania : IGI Global (2020). https://doi.org/10.4018/978-1-7998-3904-0
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Development of the hybrid MCDM model for evaluating and selecting bucket wheel excavators for the modernization process
This paper presents a methodology for evaluating and ranking different bucket wheel excavators (BWE) for determining which machine should enter in the process of revitalization and modernization. Various multicriteria methods are used. Combining them achieves the best effect when choosing BVE for the modernization process. AHP, TOPSIS, VIKOR, and PROMETHEE methods are used. The hybrid models are developed from the multi-criteria decision making (MCDM) methods and they are used to evaluate the basic indicators that characterize the operation of ...Snezana Savkovic, Predrag Jovancic, Stevan Djenadic, Milos Tanasijevic, Filip Miletic. "Development of the hybrid MCDM model for evaluating and selecting bucket wheel excavators for the modernization process" in Expert Systems with Applications, Elsevier BV (2022). https://doi.org/10.1016/j.eswa.2022.117199
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Application of machine learning for diagnosing the operation of a deep well pump in oil production
Maja Trikić (2024)This paper will thoroughly examine how machine learning can improve the diagnosis of deep well pumps by analyzing the role and function of the pumps, dynamograms, sensor technologies, and diagnostic methods.Our analysis will provide insights into modern techniques and approaches for enhancing the performance and reliability of oil production systems, targeting cost reduction and increased operational efficiency.deep well pump, dynamograms, machine learning, diagnostics of operating coditions,Random Forest, XGBoost... - The model stores al] training examples and compares new data to them. It does not create an explicit model but uses examples to make decisions. For example, K-Nearest Neighbors (KNN). 8. Model-Based Learning - The model builds a generalized model based on the training data. This model is used ...
... assess model performance and prevent overfitting. 27 c.Evaluation- Measures accuracy and methodology. Assess the model's accuracy in predicting the correct pump states. Analyze errors and misclassifications to further improve the model. • Model Application a. Prediction - The model is used ...
... and F1-score are used. b.Cross-Validation- A technique for assessing how the model will perform on unseen data, helping to evaluate the model's stability and robustness. • Model Application a.Prediction - The model is used to predict the pump's condition in real-time based on current sensor ...Maja Trikić. Application of machine learning for diagnosing the operation of a deep well pump in oil production, 2024
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Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example
Miloš Marjanović, Biljana Abolmasov, Igor Peshevski, James Reeves, Irena Georgievska. "Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example" in Understanding and Reducing Landslide Disaster Risk, Springer International Publishing (2020). https://doi.org/10.1007/978-3-030-60227-7_29
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Model of the Geomagnetic reference field of the Republic of Serbia
Spomenko J. Mihajlović, Vesna Cvetkov (2024)Spomenko J. Mihajlović, Vesna Cvetkov. "Model of the Geomagnetic reference field of the Republic of Serbia" in 5th Congress Geologists of the Republic of North Macedonia, Ohrid, 28-29. 10. 2024, Македонско геолошко друштво (2024)
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A Model for Determining the Dependability of Continuous Subsystems in Coal Mines Using the Fuzzy Logic Approach
Nikola Stanić, Miljan Gomilanović, Petar Marković, Daniel Krzanović, Aleksandar Doderović, Saša Stepanović (2024)This study presents a unique model for assessing the dependability of continuous parts of combined systems in open-pit mining through the application of fuzzy logic. Continuous sub-systems as part of the combined system of coal exploitation in surface mines have the basic function of ensuring safe operation, high capacity with high reliability, and low costs. These subsystems are usually part of the thermal power plant’s coal supply system and ensure stable fuel supply. The model integrates various independent partial ...fuzzy logic, max-min composition, continuous part of combined system (CCS), open pit, mining, dependabilityNikola Stanić, Miljan Gomilanović, Petar Marković, Daniel Krzanović, Aleksandar Doderović, Saša Stepanović. "A Model for Determining the Dependability of Continuous Subsystems in Coal Mines Using the Fuzzy Logic Approach" in Applied Sciences, Basel, August 2024, MDPI (2024). https://doi.org/https://doi.org/10.3390/app14177947
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Osnaživanje energetske tranzicije u sektoru domaćinstva u Srbiji: integrativni pristup
Boban Pavlović (2023)Glavni cilj istraživanja bio je da se razvije metodološki pristup koji bi podržao proces energetskog planiranja tranzicije u grejanju domaćinstava, uzimajući u obzir specifičnosti ovog sektora. Kako bi se procenili mogući tokovi energetske tranzicije u grejanju domaćinstava i analizirali politički instrumenti za ubrzanje ovog procesa, razvijen je simulacioni model zasnovan na agentima (Agent Based Model – ABM). Simulacioni model je primenjen na slučaju energetske tranzicije u sektoru domaćinstva u Srbiji. Prethodno su kroz istraživanje prikupljeni podaci o grejanju domaćinstava ...energetska tranzicija, energetsko planiranje, energetsko modeliranje, obnovljivi izvori energije, domaćinstva, ponašanje potrošačaBoban Pavlović. "Osnaživanje energetske tranzicije u sektoru domaćinstva u Srbiji: integrativni pristup" in Energija, ekonomija, ekologija (2023)
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Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit
... the values obtained by experimental measurements [6]. Model 1 – Determining the parameters by applying the least square method. The Least Square Method is mainly used to obtain the parameters K and n which represents a common model. Model 2 — Determining the parameters through the application ...
... of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Analysis of a simplified model for determining ...
... ofjers the analysis of the simplified model for defining parameters of the oscillation equation at the Kovilovača open pit, in eastern Serbia. On the basis of calculation on concrete example of mass blasting, it has been stated that the simplified model may be used in order to calculate rock mass ...Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac. "Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit" 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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Fuzzy Model for Risk Assessment of Machinery Failures
The main goal of this research was the development of an algorithm for the implementation of negative risk parameters in a synthesis model for a risk level assessment for a specific machine used in the mining industry. Fuzzy sets and fuzzy logic theory, in combination with statistical methods, were applied to analyze the time picture state of the observed machine. Fuzzy logic is presented through fuzzy proposition and a fuzzy composition module. Using these tools, the symmetric position of the ...... fuzzy inference approach was used in an outcome calculation. The main benefit of the proposed model is being able to use numerical and linguistic data in a risk assessment model. The proposed risk assessment model, using fuzzy logic conclusions and min–max composition, was used on a mobile crushing machine ...
... fuzzy inference approach was used in an outcome calculation. The main benefit of the proposed model is being able to use numerical and linguistic data in a risk assessment model. The proposed risk assessment model, using fuzzy logic conclusions and min-max composition, was used on a mobile crushing machine ...
... incorporated this into a comprehensive model for risk level assessment for a certain machine used in the mining industry. The example of risk assessment model developed in this research is for a mobile crushing machine, the Lokotrack LT 1213S. The developed model presents a new methodological approach ...Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković. "Fuzzy Model for Risk Assessment of Machinery Failures" in Symmetry, MDPI AG (2020). https://doi.org/10.3390/sym12040525
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Hybrid Stochastic-Grey Model to Forecast the Behavior of Metal Price in the Mining Industry
Zoran Gligorić, Miloš Gligorić, Dževdet Halilović, Čedomir Beljić, Katarina Urošević. "Hybrid Stochastic-Grey Model to Forecast the Behavior of Metal Price in the Mining Industry" in Sustainability (2020). https://doi.org/10.3390/su12166533
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Geotehnički uslovi izgradnje nadvožnjaka "Balajnac" na autoputu E-80 deonica: Niš - Merošina
Dragoslav Rakić, Nikola Božović (2024)U sklopu prve deonice autoputa E-80 Niš – Merošina, izgrađen je nadvožnjak u zoni sela Balajnac koji je oslonjen na tri stubna mesta na međusobnom rastojanju od oko 26 m. Svaki stub je fundiran na šipovima i to sa predloženim rasporedom od 2 šipa u grupi na međusobnom rastojanju od 3.6 m. U radu su na osnovu izvršenih geotehničkih istraživanja terena, analizirani rezultati nosivosti vertikalno opterećenog šipa prečnika 1.2 m i dužine šipa od L = 23 m. Analiza ...Dragoslav Rakić, Nikola Božović. "Geotehnički uslovi izgradnje nadvožnjaka "Balajnac" na autoputu E-80 deonica: Niš - Merošina" in Peti Srpski kongres o putevima, Beograd, 30-31.05.2024., Beograd : Srpsko društvo za puteve "Via Vita" (2024)
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Rezultati geoloških istraživanja lignita Kostolačko-kovinskog ugljonosnog basena – geološke i morfostrukturne karakteristike
Bogoljub Vučković, Biljana Radovanović, Vesna Matić, Lidija Glamočanin, Bogdan Radić, Ksenija Eraković, Dragana Životić (2022)Geološka istraživanja Kostolačkog basena i ležišta Kovin vrše se više od 80 godina, dok eksploatacija traje više od 100 godina. Tokom dugog perioda rudarskih aktivnosti na površini od oko 320 km2, izbušeno je preko 3.200 bušotina i više od 265.000 m jezgra. Nova saznanja o geološkim karakteristikama, morfologiji i kvalitetu ugljenih slojeva nameću neophodnost reinterpretacije i izrade jedinstvenog 3D modela Kostolačko-kovinskog basena. Primenom savremenih softverskih paketa olakšano je povezivanje ugljenih slojeva sa posebnim osvrtom na morfologiju i kvalitet slojeva i ...Bogoljub Vučković, Biljana Radovanović, Vesna Matić, Lidija Glamočanin, Bogdan Radić, Ksenija Eraković, Dragana Životić. "Rezultati geoloških istraživanja lignita Kostolačko-kovinskog ugljonosnog basena – geološke i morfostrukturne karakteristike" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
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Steel Arch Support Deformations Forecast Model Based on Grey–Stochastic Simulation and Autoregressive Process
Relatively large deformations of the steel arch support in underground coal mines in the Republic of Serbia present one of the main problems for achieving the planned production of coal. Monitoring of the critical sections of the steel arch support in the underground roadways is necessary to gather quality data for the development of a forecasting model. With a new generation of 3D laser scanners that can be used in potentially explosive environments (ATEX), deformation monitoring is facilitated, while ...čelična podgrada, prognoza deformacija, vremenske serije, grey-stohastička simulacija, autoregresija, podzemni rudnik ugljaLuka Crnogorac, Suzana Lutovac, Rade Tokalić, Miloš Gligorić, Zoran Gligorić. "Steel Arch Support Deformations Forecast Model Based on Grey–Stochastic Simulation and Autoregressive Process" in Applied Sciences, MDPI AG (2023). https://doi.org/10.3390/app13074559
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Geotehnički uslovi izgradnje metro stanice „Savski trg“ – beogradski metro linija 1
Ukrštanje linija 1 i 2 beogradskog metroa, planirano je na lokaciji “Savski trg” gde će se izgraditi zajednička metro stanica. Zbog složene konstrukcije objekta i različite dubine dijafragmi, koja na delu metro linije 2 iznosi preko 40 m, planirana je fazna izgradnja. U vezi sa tim u radu je prikazan način definisanja geotehničkog modela, kao i geotehnički proračuni u kojima su analizirani: fazni načini iskopa, filtraciona analiza, uticaj pornih i efektivnih napona na stabilnost dijafragme, horizontalna i vertikalna ...beogradski metro, metro stanica, geotehnički model, stabilnost dijafragme, horizontalna pomeranja, vertikalna pomeranjaDragoslav Rakić, Nemanja Stanić, Josip Išek, Slavoljub Stojković. "Geotehnički uslovi izgradnje metro stanice „Savski trg“ – beogradski metro linija 1" in Geotehnički aspekti građevinarstva i zemljotresno inženjerstvo – Vrnjačka Banja, 01-03. novembar 2023., Beograd : Savez građevinskih inženjere Srbije (2023)
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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).... European financial option). Analitička rešivost Black Scholes jednačine jedan je od razloga za veliku primenu ovog modela. Sledeće pretpostavke su od suštinskog značaja za primenu Black -Scholes modela: Proces utvrđivanja cena je kontinualan i nema skokova cena sredstava. Cene akcija ne mogu ...
... kao što su: ležišta uglja, boksita, glina, peska ili fosfata. 3D modeli (slika 3.7) izrađuju se kod ležišta većih dimenzija koja imaju izražene sve tri dimenzije. Rudna tela se mogu predstaviti blokovima, pa otuda i naziv blok model ležišta. Veličinu i lokaciju blokova je moguće predstaviti prostorom ...
... ispravno ukoliko je povećanje prihoda veće od povećanja troškova, odnosno ako je smanjenje troškova 51 veće od smanjenja prihoda. Ovo izgleda očigledno, međutim, njegova primena nije uvek očigledna, a korišćenje prosečnih troškova kao osnovnog modela za donošenje odluke može dovesti do greške ...Daniel P. Kržanović. "Model za optimizaciju graničnog saržaja metala u rudi u funkciji dugoročnog planiranja površinskih kopova" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2016-06-14)