Претрага

Упит dcterms_creator_txt:Predrag Jovancic

282 items

  • Development of the hybrid MCDM model for evaluating and selecting bucket wheel excavators for the modernization process

    Snezana Savkovic, Predrag Jovancic, Stevan Djenadic, Milos Tanasijevic, Filip Miletic (2022)
    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 ...
    višekriterijumsko odlučivanje, rotorni bageri, modernizacija, ekspertska analiza

  • 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 ...
    rizik, inženjerski sistemi, fazi logika, višekriterijumske metode

  • 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 ...
    Fuzzy theory, hydraulic excavator, selection, quality of service, asset management

  • A Fuzzy Expert Model for Availability Evaluation

    Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić (2019)
    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 ...
    raspoloživost, ekspertski sistem, fazi teorija, buldozeri
    ... .bg.ac.rs Radisa Djuric TPPs-OCMs Kostolac Electric Power Industry of Serbia Kostolac, Serbia radisa.duric@te-ko.rs Predrag Jovancic Faculty of Mining and Geology University of Belgrade Belgrade, Serbia predrag.jovancic@rgf.bg.ac.rs Abstract—Each technical system ...
    ... Evaluation Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] A Fuzzy Expert Model for Availability Evaluation | Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić | Proceedings of the ...
    ... and synthesis using fuzzy sets and 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 ...

  • Effectiveness Analysis of Different Bucket-wheel Excavators

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić (2021)
    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 ...
    bucket-wheel excavator, open-pit coal mine, mining, multi-criteria decision methods

  • Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine

    Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović (2019)
    Availability is one of the most used terms in maintainability engineering. This concept is used to denote: The quality of service of an engineering system, i.e., machines, weak points’ analysis, asset management, as well as making decisions in the process of life cycle management. Availability is an overall indicator and contains partial indicators that are oriented towards reliability, maintenance, and logistical support. Availability presents a variable value and changes in time and space. Usually, availability is shown as the ...
    raspoloživost, fazi teorija, AHP višekriterijumska analiza, eksperska ocena, buldozer
    ... 13. Tanasijevic, M.; Ivezic, D.; Jovancic, P.; Catic, D.; Zlatanovic, D. Study of Dependability Evaluation for Multi-hierarchical Systems Based on Max–Min Composition. Qual. Reliab. Eng. Int. 2013, 29, 317–326. [CrossRef] 14. Tanasijevic, M.; Ivezic, D.; Jovancic, P.; Ignjatovic, D.; Bugaric, U. ...
    ... PA, USA, 2000. 29. Djenadic, S.; Jovancic, P.; Ignjatovic, D.; Miletic, F.; Jankovic, I. Analiza primene višekriterijumskih metoda u optimizaciji izbora hidrauličnih bagera na površinskim kopovima. Tehnika 2019, 70, 369–377. [CrossRef] 30. Ignjatovic, D.; Jovancic, P. Optimisation of Operation and ...
    ... fuzzy methodology an introductory overview. Fuzzy Sets Syst. 1996, 83, 113–133. [CrossRef] 10. Miodragovic, R.; Tanasijevic, M.; Mileusnic, Z.; Jovancic, P. Effectiveness assessment of agricultural machinery based on fuzzy sets theory. Expert Syst. Appl. 2012, 39, 8940–8946. [CrossRef] 11. Ebramhimipour ...

  • The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers

    Dragan Ignjatović, Predrag Jovančić, Stevan Đenadić, Ivan Janković, Ivica Ristović (2019)
    One of the most important prerequisites for the successful operation of the open-cast lignite mine is to carry out all the auxiliary works timely with the necessary quality. The most important and most commonly used auxiliary machines are bulldozers. Engaging time of bulldozers use is in direct relation with the coefficients of the time and capacity utilization of the continuous system for the excavation of coal and tailings, which indicates their importance. More than 100 bulldozers have been hired ...
    open-cast coal mine, auxiliary works, bulldozers, optimization, availability
    ... Ignjatović, Predrag Jovančić, Stevan Đenadić, Ivan Janković, Ivica Ristović Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers | Dragan Ignjatović, Predrag Jovančić, Stevan ...
    ... 297-305. Life Cycle Asset Management, Life Cycle Engineering, Inc. Available online: www.LCE.com 6. Jankovic, I.; Djenadic, S.; Ignjatovic, D.; Jovancic, P.; Subaranovic, T.; Ristovic, I. Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining. Energies 2019, 12, 2245. https://doi ...
    ... September 2019, Vrdnik, Serbia THE OPTIMIZATION OF AUXILIARY MACHINERY IN OPEN-CAST LIGNITE MINES: A CASE STUDY OF BULLDOZERS Dragan Ignjatović!, Predrag Jovančić!, Stevan Đenadić!, Ivan Janković?, Ivica Ristović! !- University ог Belgrade – Faculty ог Mining and Geology, Belgrade, SERBIA, dragan ...

  • 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
    ... Article Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining Ivan Jankovic 1, Stevan Djenadic 2, Dragan Ignjatovic 2, Predrag Jovancic 2, Tomislav Subaranovic 2 and Ivica Ristovic 2,* 1 Ministry of Mining and Energy, 11000 Belgrade, Serbia; ivan.jankovic@mre.gov.rs 2 Faculty ...
    ... Article Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining Ivan Jankovic 1, Stevan Djenadic 7, Dragan Ignjatovic *, Predrag Jovancic 2, Tomislav Subaranovic 2 and Ivica Ristovic *’* 1 2 Ministry of Mining and Energy, 11000 Belgrade, Serbia; ivan.jankovic@mre.gov.rs Faculty ...
    ... Mining and Geology, University of Belgrade, 11000 Belgrade, Serbia; stevan.djenadic@rgf.bg.ac.rs (S.D.); dragan.ignjatovic@rgf.bg.ac.rs (D.I.); predrag jovancic@rgf.bg.ac.rs (PJ.); tomislav.subaranovic@ref.bg.ac.rs (T.S.) Correspondence: ivica.ristovic@rgf.bg.ac.rs; Tel.: +381-11-3241-121 check for Received: ...

  • Indeksi kontrole održavanja i korišćenja rotornog bagera

    Jovana Mitrović, Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić, Filip Miletić (2023)
    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 ...
    rudarstvo, rotorni bager, indeksi održavanja, indeksi korišćenja, TOPSIS

  • Determining the Availability of Continuous Systems at Open Pits Applying Fuzzy Logic

    Miljan Gomilanović, Miloš Tanasijević, Saša Stepanović (2022)
    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 композиција

  • Izbor rotornih bagera za proces revitalizacije: primer rotornih bagera SRs 1200 u rudarskom basenu Kolubara

    Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić, Filip Miletić, Goran Todorović, Dragan Novaković (2020)
    Revitalizacija je proces ili skup tehničkih zahvata na mašini kojim se vrši zamena svih dotrajalih ili oštećenih delova metalne konstrukcije. Sastavni deo procesa revitalizacije je i modernizacija zastarele elektro-mašinske opreme. Principi revitalizacije sasvim sigurno nisu sadržani u okviru redovnog godišnjeg ili dnevnog održavanja. Oni predstavljaju održavanje onih veličina koje su značajne za mašinu kao celinu (u ovom slučaju rotorni bager). U ovom radu su analizirani rotorni bageri oznake SRs 1200. Na površinskim kopovima rudarskog basena Kolubara takvih bagera ima ...
    Rotorni bageri, revitalizacija, SRs1200

  • Ostvarivanje dobiti pri uvođenju sistema agregatnih zamena na osnovnoj rudarskoj mehanizaciji površinskih kopova EPS

    Predrag Jovančić, Ignjatović Dragan, Đenadić Stevan (2021)
    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 ...
    agregatne zamene, održavanje, mehanizacija, Benefit Cost analiza

  • Priprema ruda antimona

    Lazić Predrag (2014)

  • Priprema ruda olova i cinka

    Lazić Predrag (2014)

  • Postrojenja za pripremu ruda metala i uglja

    Lazić Predrag (2014)

  • [Без наслова]

    Lazić Predrag (2012)

  • Opravdanost i domen primene zasipavanja otkopanog prostora pri podzemnoj eksploataciji ležišta uglja

    Predrag Dimovski (1992)
    Podzemna eksploatacija, zasipavanje, ugalj

  • Ispitivanje uslova rada čekićne drobilice na efekte drobljenja i habanje drobećih površina pri usitnjavanju krečnjaka

    Predrag Lalić (1991)
    Čekićna drobilica, drobljenje, habanje, usitnjavanje krečnjaka

  • Utvrđivanje korelacije između fizičko-mehaničkih svojstava mermera i efekta drobljenja

    Predrag Lazić (1994)
    Mermer, efekti drobljenja

  • Uticaj uspora HE Đerdap I na pojavu šteta usled visokih nivoa podzemnih voda na području Velikoselskog rita

    Predrag Pajić (2012)
    HE Đerdap I, uticaj uspora, Velikoselski rit.