Претрага

Упит dcterms_subject_txt:diagnostics of operating coditions,Random Forest

2837 items

  • Applicability of the risk ranking methodology designed for water reservoirs to tailings storage facilities

    Dragana Nišić, Dinko Knežević, Aleksandar Cvjetić, Neda Nišić, Vladimir Jovanović (2022)
    The risks associated with operating water reservoirs and tailings storage facilities (TSFs) are different because of their different purposes, methods of construction and operation, and characteristics of the materials impounded and their flow behaviour. Regardless of the differences, these two types of structures are often put in the same category when it comes to risk assessment and the application of relevant methodologies, which may result in unrealistic outcomes. In this paper we investigate whether it is possible to apply ...
    procena rizika, akumulacije za vodu, jalovište, TSF, ICOLD, FMEA

  • Development of the Cost-Based Model for Monitoring the Lifetime of the Earth Moving Machines

    Ugljesa Bugarić, Milos Tanasijević, Stevan Djenadić, Dragan Ignjatović, Ivan Janković (2022)
    This paper presents the model for the identification of reference points on the lifetime curve of engineering systems. This curve commonly represents the increase and decline of failure in relation to time. A direct correlation between failure rate and costs is assumed in this paper, therefore, statistical and empirical analysis of costs provided reference points. This approach is used for positioning stages of the engineering system’s lifetime with a minimal number of failures and costs, regardless of whether these ...
    Electrical and Electronic Engineering,Industrial and Manufacturing Engineering, Control and Optimization, Mechanical Engineering, Computer Science (miscellaneous), Control and Systems Engineering

  • Palaeoflora of Kamenica (Pranjani Basin, western Serbia)

    Zorica Lazarević, Ljubica Milovanović, Jelena Milivojević, Ivana Vasiljević (2019)
    Palaeofloras of the Paleogene in Serbia are relatively rare, especially in comparison with floras from Neogene sediments. Most Paleogene phytoas sociations from the territory of Serbia existed in a dry and warm climate. The youngest Paleogene phytoassociation originates from the Pranjani Basin (Western Serbia), locality Kamenica. The age of this palaeoflora is determined as Late Oligocene. This fossil plant assemblage is different from other Paleo gene phytoassociations.The palaeoflora from Kamenica is characterized with leaf imprints larger than in other ...
    макрофлора, млађи олигоцен, Прањански басен, Каменица
    ... while the presence of notophyllous Palaeoflora of Kamenica (Pranjani Basin, western Serbia) Geol. an. Balk. poluos., 2019, 80 (2), 53–63 55 Table 1. Identified taxa from Kamenica locality. leaves are rare. representatives of humid subtropi- cal forest dominated in paleophytocenosis of Ka- menica: G ...
    ... palaeoflora. The other representative of the humid subtropical forest is represented by the Myrica (Plate 5, Figs. 1, 5) and Platanus neptuni (Plate 4, Fig. 10). These plant forms inhabited the banks of the river and the margins of the lake basin. a significant number of samples in this locality belongs ...
    ... научни рад 1 University of Belgrade – Faculty of Mining and Geology, Department of Paleontology, Kamenička 6, 11000 Belgrade, Serbia. E-mails: zorica.lazarevic@rgf.bg.ac.rs; jelena.milivojevic@rgf.bg.ac.rs 2 University of Belgrade – Faculty of Mining and Geology, Department of Geophysics, Đušina 7, 11000 ...

  • Cultural Heritage and Protection of Hand-Wheeled Pottery Manufacture in Western Serbia: Characteristics of Zlakusa Pottery Based on Sem-Eds and Optical Microscopy

    Milošević Maja, Zdravković Alena, Đordjević Biljana, Jelić Ivana (2021)
    ... the application of a modern mould technique. A microscopic examination of the thin sections revealed a uniform mineral composition. No significant differences were observed regarding the inner sections of the pots and their outer rims. Observed pores in sample 1 are of random orientation and ...
    ... higher amount of calcite grains. EDS analysis gives clear differences in the chemistry of the samples. Sample 1 has a higher content of most investigated elements when compared to sample 2, except K and Ca. Amount of K and Ca elements could indicate the presence of a higher amount of illite minerals ...
    ... the obtained knowledge in the preservation of this type of cultural heritage in Serbia. Results and discussion Clay paste is a mixture of raw clays, consisted of kaolinite/halloysite, illite and smectite minerals followed with smaller amounts of quartz, feldspar and iron oxy/hydroxides ...

  • Coal homogenization stockyard sizing “Tamnava – Zapad” case study

    Božo Kolonja, Dinko Knežević, Ranka Stanković, Dejan Stevanović, Detlef Trummer (2016)
    ... and then as the sum of all piles. Standard deviation was used to measure success of operation and the required number of layers at the stockyard, while the selected travel speed of the stacker depends on coal quality, the operating rate of the mining machines and the capacity of the stacker. The selected ...
    ... include an analysis of the stacker's operating capacity. This capacity depends on the operating capacity of the pit, which is quite variable in short intervals (second, minute). In order for the layer sizes to be equal, the stacker has to change travel speed depending on the quantity of coal arriving ...
    ... and maximum number of layers changes. For a pit rate of 3000 t/h, coal can be stacked in 25 to 150 layers. The example in Figure 2 shows the problem when the pit operates at a lower capacity, and in a zone containing coal with a small quality range. To avoid the stacker operating below minimum travel ...

  • Preliminary impact assessment of No2 emission from a heating plant on air pollution: case of Zemun, Serbia

    Boban Pavlović, Uroš Pantelić, Marija Živković, Dejan Ivezić (2023)
    The aim of this paper is to provide a preliminary evaluation of the impact caused by NO2 emissions from a heating plant on the local air quality. To model the spatial distribution of NO2 emissions from the heating plant, the AERMOD model was employed. The evaluation was conducted by analyzing and contrasting the simulated NO2 concentration from the heating plant with the overall NO2 concentration recorded at the nearest monitoring station over the entire heating season. The study focused ...
    AERMOD, квалитет ваздуха, моделирање дисперзије загађења, топлана, NO2 загађење

  • Geomechnical research for the new bucket wheel excavator testing at Open pit “Filijala”

    Vladimir Čebašek, Nebojša Gojković, Veljko Rupar, Miodrag Pribićević (2020)
    Since 1976 cement marl excavation at open-pit mine „Filijala” is carried out by continuous exploitation technology using bucket wheel excavator SH 400 manufactured by Orenstein und Koppel (O & K) company. Due to the bucket wheel excavator time-worn and high operating cost it was necessary to replace it with new one. In order to test the new bucket wheel excavator and prove its capacity a testing zone was defined as test block for excavation, in which the bucket wheel ...
    отпор на копање, лапорац, роторни багер

  • Increasing the Local Road Network Resilience from Natural Hazards in Municipalities in Serbia

    Biljana Abolmasov, Miloš Marjanović, Ranka Stanković, Uroš Đurić, Nikola Vulović (2024)
    lokalni putevi, prirodni hazardi, otpornost na klimatske promene, MaPLoRds

  • Димензионисање камионског транспорта јаловине на површинском копу Угљевик Исток 1

    Наталија Терзић (2024)
    Напредовањем рударења дошло је до потребе за експлоатацијом сложенијих и сиромашнијих лежишта, самим тим и повећањем трошкова.Профитабилна експлоатација лежишта минералних сировина захтева детаљну анализу свих техничко-економских фактора.Два најутицајнија фактора на профитабилност експлоатације руде јесу откопавање и транспорт, због тога је неопходно направити изводљив стратешки план који ће бити у складу са свим ограничењима и омогућити испуњавање свих планираних резултата.Транспорт на површинским коповима одвија се паралелно са осталим процесима експлоатације, стога је неопходно да сви системи буду усаглашени како не ...
    дисконтинуални транспорт, откривка, транспортне трасе, Тalpac, капацитет, камион, багер
    ... 20 Average Cycle Time - min/Cyce 28,68 Fleet Size s Average No. of Bucket Passes 5,00, yulage System Production per Year - tonne/Year 4246115 Discourtted Capital Cost S/tonne O,OD _ Loading Methodology Discounted Operating Cost S/tonne .00 Single sided Discounted Average Cost S/tonne 000 FuliTruck ...
    ... tonne 6.65 Operating Hours per Year OpHr/Year 4,862.00 ·Op.hrs factored by availabilty Average Operating Shifts per Year shifts/Year 748.00 ” Shifts factored by availabilty Average Bucket Cycle Time min 0.50 Production per Operating Hour tonne 418.99 Production per Loader Operating Shift tonne ...
    ... factored by avail. Wait Time per Operating Hour min 17.93 Mvailability % 55.00 Payloadin Template ftonne 57.56 Operating Hours per Year OpHri/Year 2,674.10 Average Payload tonne 58.32 Production per Operating Hour ftonne 190.45 Production per Loader Operating Shift tonne 681 Production per ...

  • Heavy metals in lignite and soil of Kostolac-Kovin coal basin, eastern Serbia - comparative analysis with selected cities in Serbia, region, Europe and world

    Bogoljub Vučković, Bojan Dimitrijević (2023)
    The Kostolac-Kovin coal basin with an area of 320 km2, with 5 separate layers of coal and with a total of about 5.7 Bt of geological resources and reserves represents an exceptional potential for coal production in Serbia. The coal resources listed in this way are not fully exploitable, but they represent potential for consideration. In this paper, we deal with the geochemical characteristics of coal seams and perform a comparative analysis of coal affectation on the environment. With ...
    lignite, heavy metals, concentrations
    ... ATBOTTOM: Forest, FRA Murcia, ESP Oslo, NOR Galway, IRL Moscow 3,RU Figure 8. Presentation of the content of Zn, Pb and Cu in the urban and recreational top soil in the cities ofthe Furope; yellow – I, H and II Kostolac coal, black - the most polluted soil Figure 8 shows that the contents of Zn, ...
    ... productive humus layer of the soil that are at the top of the sedimentation sequence of this area. 181 3. COMPARATIVE PRESENTATION OF THE CONTENT OF HM IN THE LIGNITE OF THE BASIN AND SELECTED EXAMPLES - SERBIA, REGION, EUROPE AND THE WORLD For easier understanding of the content of these HM, we performed ...
    ... the geochemical characteristics of coal seams and perform a comparative analysis of coal af}ectation on the environment. P/ith 155 analyzes of HM from coal, 45 from ash, 165 from gravel and 30 from soil, we perform analysis of horizontal and vertical distribution of HM and comparative analysis. B/hat ...

  • Opremanje bušotine X zavojnom pumpom

    Milan Filipović (2024)
    Ovaj rad se bavi osnovnim pojmovima i karakteristikama zavojnih pumpi.Prikazan je sklop zavojnih pumpi i njena prateća oprema. Objašnjen je princip rada zavojnih pumpi kao i uloga svakog mašinskog elementa koji se nalazi u pumpi. Razmotrene su prednosti i nedostaci primene ovih primarnih mehaničkih metoda eksploatacije ugljovodonika. Dat je uvid u inovativna rešenja problematike primene zavojnih pumpi. Na konkretnom primeru bušotine X su prikazani problemi kao i rešenja primene ovih primarnih mehaničkih metoda u praksi. Napravljena je detaljna analiza ...
    zavojne pumpe, oprema, primarne mehaničke metode, ugljovodonici, analiza rada
    ... l University — Faculty of Electrical Engineering and Electrical Equipment, Russia • Lei ZHENG, Xiaodong WU, Ruidong ZHAO, Huachang LI and Mengyun LIU, MOE Key Laboratory of Petroleum Engineering, China University of Petroleum (Beijing), 102249, "Study on Performance of Progressing Cavity Pumps ...
    ... радовима запослених доступним у слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.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 ...
    ... ekscentričnim okretanjem. Na slici 2 je prikazan Još jedan shematski prikaz radnog kola zavojne pumpe. ı Centreline of T~— Rotor ' — —:!d _— 'Centreline of Rotor * y W [entreline of Stator F| |2 = s e Š Rotor contacts :, y- stator here F!ud * O creating a Filled 5 sealed cavity Caviles ...

  • Analiza osnovnih indikatora upotrebnog kvaliteta mašina pomoćne mehanizacije na površinskim kopovima uglja

    Stevan Đenadić, Dragan Ignjatović, Predrag Jovančić, Milena Lekić, Žarko Aleksić, Ivan Janković (2022)
    Izbor optimalnog tipa mašine i adekvatno upravljanje kroz životni vek je kompleksan zadatak. Osnovna pitanja koje se postavljaju prilikom rešavanja ovog zadatka vezana su za stepen zadovoljenja rada mašine i optimalan trenutak zamene iste. U ovom radu je izvršena analiza rada dozera koji su u radu na površinskom kopu lignita RB Kolubara. Analizom je obuhvaćeno 4 različita proizvođača dozera a to su: Caterpillar, Dressta i Shantui i Liebherr. Analiza je izvršena sa aspekta ukupnih troškova koji se stvaraju i ...
    rudarstvo, mehanizacija, upotrebni kvalitet, troškovi, empirijska raspoloživost

  • Automated blasthole drilling in surface mining

    Milanka Negovanović, Lazar Kričak (2021)
    Све већи развој аутоматизације у рударској индустрији утицао је на увођење нових решења у области аутоматизације бушења минских бушотина на површинским коповима. Највећи светски произвођачи опреме за бушење развијају решења аутоматизације која омогућавају рударским компанијама да постигну најбоље резултате у погледу квалитета, продуктивности и оперативних трошкова. Решења из области аутоматизације бушења се крећу од операција даљинског управљања до потпуно аутоматизованог бушења, праћења података у реалном времену и разних специјализованих алата за управљање подацима који повећавају безбедност и продуктивност ...
    Аутоматизација, бушилица,тачност, бушење,рударство,систем даљинског управљања,безбедност, продуктивност

  • Sitni, ali bitni: uloga sitnih sisara, herpetofaune i mekušaca u rekonstrukciji pleistocenskih paleosredina

    Katarina Bogićević, Draženko Nenadić, Dragana Đurić, Mihajlo Jovanović, Aleksandra Savković (2023)
    Fosilni ostaci životinja i biljaka imaju važnu ulogu u rekonstrukciji pleistocenskih paleosredina. U ovom radu opisan je značaj tri grupe životinja: sitnih sisara, herpetofaune I mekušaca. Mada je za rekonstrukciju važan sastav čitave asocijacije, nalasci pojedinih vrsta mogu biti dovoljno indikativni da otkriju tip staništa ili klimatske uslove. Posebnu teškoću pri rekonstrukciji paleosredina u Srbiji predstavlja činjenica da klimatske promene na Balkanskom poluostrvu nisu bile tako oštre kao u srednjoj i zapadnoj Evropi, pa ne postoji drastična razlika u ...
    ... while in warmer periods forest dwellers are more common. Methods of reconstruction: The simplest and at the same time the most frequently used method for habitat type reconstruction is the method of ecological groups. For each species, it is determined in which group of habitats it most often ...
    ... variations, but also data on global climate changes. Based on the remains of molluscs, other significant data useful for the reconstruction of palaecoenvironments can be obtained, such as whether the immediate environment was forest, steppe or open type (wet meadows to steppe), whether these are species ...
    ... Central European model of the sequence of individual species during periods of cooling and warming. In the cave deposits of Serbia of Late Pleistocene age, the herpetological associations arc dominated by species that, according to Bohme's model, appear in the warmer stages of the Quaternary climatic ...

  • 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

  • Production information system of the Pljevlja coal mine

    Božo Kolonja, Ranka Stanković, Filip Vuković (2018)

  • 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

  • Extreme Rainfall Event and Its Aftermath Analysis—IPL 210 Project Progress Report

    Biljana Abolmasov, Mileva Samardžić Petrović, Ranka Stanković, Miloš Marjanović, Jelka Krušić, Uroš Đurić (2021)
    Landslides, Extreme precipitation, Data analysis, IPL project report

  • Improving efficiency of thermal power plants through mine coal quality planning and control

    Mirjana Banković, Dejan Stevanović, Milica Pešić, Aleksandra Tomašević, Ljiljana Kolonja (2018)
    Главни циљ контроле квалитета угља у рудницима лигнита је снабдевање термоелектрана угљем чији квалитет мора да се креће унутар одређених квалитативних ограничења. Карактеристике угља могу да утичу на ефикасност, поузданост и расположивост како котла тако и јединица за контролу емисије. У овом раду аутори су презентовали интегрисану симулацију рударског процеса као нови приступ у истраживању променљивости калоричне вредности угља приликом експлоатације комплексног лежишта лигнита. Резултати таквог приступа омогућавају драгоцен увид у перформансе континуалног рударског система у смислу контроле променљивости ...
    mine planning, variability of coal quality, simulation, coal blending

  • WS4LR - a Worksation for Lexical Resources

    Cvetana Krstev, Ranka Stanković, Duško Vitas, Ivan Obradović (2006)
    Lexical Resources, Wordnet, Serbian
    ... under Windows 2000/XP/2003 operating system with at least 256MB (preferably 512MB) of internal memory. The solution consists of five projects, the main exe ConvertCP project and four .Net libraries of classes, as depicted in Figure 6. Figure 6. Project components of WS4LR solution The user ...
    ... operates on the .NET platform and runs on a personal computer under Windows 2000/XP/2003 operating system with at least 256MB of internal memory. 1 Introduction The Human Language Technology group at the Faculty of Mathematics has been developing various lexical resources over quite a long period ...
    ... and the technological point of view. Although the HLT group made every reasonable effort to keep the ever growing pool of resources as coherent and standardized as possible, a certain level of heterogeneity was inevitable. Hence, due to the growth of the volume of resources as well as their h ...