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Упит dcterms_subject_txt:Probability and Uncertainty

2341 items

  • 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

  • A multi-criteria approach for assessing the potential of renewable energy sources for electricity generation: Case Serbia

    Boban Pavlović, Dejan Ivezić, Marija Živković (2021)
    When assessing the potential of renewable energy alternatives for electricity generation, it is necessary to implement a multi-perspective approach that includes economic, technical, environmental, and socio-political criteria. For the evaluation of criteria and alternatives, the Fuzzy Analytical Hierarchy Process (FAHP) method is applied. The obtained weights are formed according to the values of energy indicators and expert judgments. The use of a fuzzy numerical value scale for the assessment of expert judgments and energy indicators provides a more sensitive ...
    Proizvodnja električne energije, Obnovljivi izvori energije, Višekriterijumsko odlučivanje, Srbija
    ... shortage, and uncertainty inherent in decisions made by human beings (Rani et al., 2020). For decomposing the complex objective of the study into a hierarchical structure and for dealing with uncertainty in a decision-making process, FAHP appeared to be a useful tool. FAHP combines the fuzzy theory and the ...
    ... deci- sion analysis (MCDA) is known as an operational assessment and decision-making method appropriate for dealing with complex problems where uncertainty, conflicting criteria, and different interests need to be evaluated from qualitative and quantita- tive aspects (Campos-Guzmán et al., 2019). Various ...
    ... The AHP method structures a problem hierarchically, descending from an objective to criteria, sub-criteria, and alternatives in successive levels (Saaty, 1990). To handle imprecision and uncertainty in the pairwise comparison process, the AHP scale is replaced with fuzzy numbers that represent the linguistic ...

  • Refinement of waste phosphogypsum from Prahovo, Serbia: characterization and assessment of application in civil engineering

    Josip Išek, Lazar Kaluđerović, Nikola Vuković, Maja Milošević, Ivana Vukašinović, Zorica Tomić (2020)
    γ-spectrometry, brushite, chukhrovite, phosphogypsum, radionuclides, recrystallization
    ... radionuclides *U, “Ra, ' Th and 'K have also been reported in other studies (Sahu et al, 2014; Jung et al., 2017). The activity concentration values for natural radionuclides before and after the sealing of the samples' containers were within experimental uncertainty of the measurements, except ...
    ... using SEM-EDS and ICP-OES elemental ana- lyses. Specifically, in the PGIP sample, Al, Si and P calculated as oxides by stoichiometry amount to 1.02 wt.% in SEM-EDS ana- lysis. In addition, 10 trace elements in ICP-OES 5analysis (Table 3) comprise 0.63 wt.%, which gives a low probability of detection ...
    ... measurement uncertainty was ~10%. For uniformity in exposure estimates, the radionuclide concen- trations have been defined in terms of radium equivalent activity (Ra.q) in Bq kg'l. This allows a comparison of the activity con- centrations of materials containing various amounts of ?Ra, 5h and K according ...

  • Development of an integrated model for open-pit-mine discontinuous haulage system optimization

    Miodrag Čelebić, Dragoljub Bajić, Sanja Bajić, Mirjana Banković, Duško Torbica, Aleksej Milošević , Dejan Stevanović (2024)
    equipment selection, mine mechanization, expert judgment, linguistic variables, MCDM, FAHP

  • Fuzzy Model for Risk Assessment of Machinery Failures

    Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković (2020)
    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 ...
    fazi teorija, rizik, otkaz rudarskih mašina
    ... approach that is suitable for the analysis of processes in which uncertainty, ambiguity, subjectivity, and indeterminacy are prevalent. It was developed to treat insufficiently precise phenomena that cannot be modeled solely using probability theory or interval mathematics. Ambiguity, as a term, can be ...
    ... event, a change in circumstances, or a consequence. In this definition, uncertainty includes both events (which may or may not happen) and uncertainty caused by ambiguity or a lack of information. It also includes both negative and positive impacts on objectives. Many definitions of risk exist in common ...
    ... fuzzy Markov chains, and fuzzy Petri nets. Similar analyses have been presented by Liu et al. [22]. Their review showed the potential applicability of fuzzy set theory in addressing uncertainty in safety and reliability engineering. The numerous possibilities for applying fuzzy sets and fuzzy logic theory ...

  • A hundred years of Milutin Milanković's climate change theory - geological implications

    Dejan Radivojević (2020)
    Миланковићева теорија циклуса објављена пре сто година је најважнија теорија у наукама које проучавају климу и имала је велики утицај на дисциплине које се баве Земљом. Ипак, његов рад је чекао више од педесет година да би добио потврду. Може се рећи да Миланковићев рад највећи утицај на геологију има у изради астрономске временске скале, подршци хипотези континенталног дрифта и палеоклиматологији. Добри резултати примене астрономске временске скале на неогене седименте иницирали су примену ове методе у мезозојским и у последње ...
    циклостратиграфија, астономска временска скала, геолошка временска скала, климатске промене, континентални дрифт
    ... Geol. an. Balk. poluos., 2020, 81 (2), 87–98 91 Fig. 4.Uncertainty in the Phanerozoic international GTS 2004 (GrAdSTEin et al., 2004). A, Standard GTS division, modified; B, Estimated uncertainty (95% level of confidence); C, distribution of U-Pb and 40Ar/39Ar; D, distribution of astronomically forced ...
    ... n rates spatially and temporary varies and depend on palaeoecological and palaeogeographic conditions. Generally, well-rounded and fine-grained sediments reflect calm and slow sed- imentation, while angular coarse-grai ned sediments are mostly related to short palaeotransport and fast sedimentation ...
    ... his brothers died from tuber- culosis at young age and besides his mother jeli - saveta and grandmother, his uncle vasilije Maučević took care of him and sisters. In 1889 he left to his uncle Paja Maučević to osijek where he went to Gymnasium and very soon became the best student even though before ...

  • Препреке декарбонизацији система даљинског грејања у Србији - ставови представника топлана

    Марија Живковић, Дејан Ивезић, Бобан Павловић, Дејан Стојановић (2024)
    Производња топлоте у системима даљинског грејања у Републици Србији тренутно се заснива искључиво на процесима сагоревања, с доминантним уделом природног гаса из увоза. Иако су технологије за коришћење обновљивих и алтернативних извора енергије добро познате, њихова примена у системима даљинског грејања у Републици Србији још увек је занемарљива (око 2%). Како би се убрзао и олакшао процес транзиције ка обновљивим изворима енергије и разумело тренутно стање и перспектива, спроведена је анкета међу представницима топлана Србији. Циљ је био ...
    системи даљинског грејања, препреке, обновљиви извори енергије, Србија

  • Preliminary regional landslide susceptibility assessment using limited data

    Igor Peshevski, Milorad Jovanovski, Biljana Abolmasov, Jovan Papic, Uroš Đurić, Miloš Marjanović, Ubydul Haque, Natasha Nedelkovska (2019)
    In this paper a heuristic approach for preliminary regional landslide susceptibility assessment using limited amount of data is presented. It is called arbitrary polynomial method and takes into account 5 landslide conditioning parameters: lithology, slope inclination, average annual rainfall, land use and maximum expected seismic intensity. According to the method, in the first stage, a gradation is performed for each of the carefully selected conditioning parameters by assigning so called rating points to the grid cells on which the ...
    klizišta, podložnost
    ... validation, and uncertainty quantification in scientific computing.– Compu- ter Methods in Applied Mechanics and Engineering, 200, 25–28, 2131–2144. doi: 10.1016/j.cma.2011.03.016 ROZOS, D., BATHRELLOS, G.D. & SKILLODIMOU, H.D. (2010): Comparison of the implementation of rock engineering system and analytic ...
    ... SAVAGE, W.Z. (2008): Guidelines for landslide susceptibility, hazard and risk zoning for land use planning.– Engineering Geology, 102/3–4, 85–98. doi: 10.1016/j.enggeo. 2008.03.022 FEIZIZADEH, B. & BLASCHKE, T. (2014): An uncertainty and sensitivity analysis approach for GIS-based multicriteria landslide ...
    ... landslides were defined as translational and rotational debris and earth slides and rock falls. Over 60% of the occurrences have been defined as intermediate and deep, and those mostly occurred in debris material overlying hard rock masses or in fluvioglacial and proluvial sediments. The depth of some ...

  • Optimizacija i planiranje površinskih kopova stohastičkim modelima

    Dejan R. Stevanović (2015-05-29)
    Savremeno rudarstvo izloženo je stalnom trendu pogoršanja uslova poslovanja.Mogućnost ostvarenja ekonomskih i drugih ciljeva rudarskog projektakompromitovana je stalnim pogoršanjem kvaliteta ležišta na kojima se vršieksploatacija, kao i značajnoj dozi neizvesnosti povezane sa geološkim,ekonomskim i tehničkim parametrima proizvodnje. U ovako kompleksnimuslovima poslovanja, matematički modeli sposobni da odgovore značajnimizazovima, odnosno ponude optimalna rešenja kojima se garantuje maksimalnoispunjenje projektovanih ciljeva, nameću se kao neophodnost.Trenutni, konvencionalni pristup optimizaciji i planiranju površinskih kopovazasniva se na algoritmima, razvijenim sredinom prošlog veka čije je opšteobeležje deterministički ...
    površinski kop, planiranje, optimizacija, stohastički modeli, kontrola kvaliteta uglja, neizvesnost.
    ... Science and Technology, vol. 10, str. 323–335. Denby, B. and Schofield, D., 1994, Open pit design and scheduling by use of genetic algorithms. Transactions of the Institute of Mining and Metallurgy, Section A), Vol. 103, str.21-26. Dimitrakopoulos R., 2011, Strategic mine planning under uncertainty, stochastic ...
    ... open-pit optimization. International Journal of Surface Mining Reclamation and Environment, Vol. 2, No. 4, str. 173–179. Dominy S. C., Noppe M. A., Annels A. E., 2002, Errors and Uncertainty inMineral Resource and Ore Reserve Estimation: The Importance of Getting it Right.Exploration Mining Geology, vol ...
    ... the Institute of Mining and Metallurgy, (Section A, Mining Industry), vol. 102, str. A95-A104 Dowd, P, A, Pardo-Igúzquiza, E, 2002, The Incorporation of Model Uncertainty in Geostatistical Simulation, Geographical and Environmental Modelling, Vol.6, str. 147-169. Dowd, P. A. and Onur, A. H., 1992, Optimizing ...

  • Synergy between the mineral deposit exploration and geothermal resources assessment on the example of "Valjevo" boron and lithium deposit in Serbia

    Nebojša Atanacković, Vladimir Živanović, Ana Vranješ, Sava Magazinović, Marinko Toljić, Ana Arifović, Branislav Potić (2023)
    Exploration of mineral deposits involves a collection of vast data sets on geological characteristics of the area. These data can largely contribute to the assessment of the geothermal potential, which can lead to an increase in the share of geothermal resources in the energy mix of the extractive industry and the local community. On the example of the "Valjevo" B-Li deposit, data on structural settings and previous hydrogeological investigations were combined with the results of resource drilling and geophysical ...
    Geothermal assessment, Mineral deposit exploration, Geothermal potential, Serbia
    ... emphasis was made on understanding the structural style and depth of the Miocene cover, as well as the spatial distribution of the estimated temperatures in the Triassic reservoir. Still, uncertainty remains about the hydraulic properties and storativity of the limestone aquifer in the basement of ...
    ... Mionica and surrounding settlements. Karst groundwater under artesian pressure and elevated temperatures (17–37 "C) are taped with wells drilled below the Miocene cover in the surrounding. settlements of Paštrić, Sanković and Petnica. 3. MATERIALS AND METHODS Considering the available data and the ...
    ... probertite, ulexite, sirlezite, massive borax and Li-bearing smectite and silinaite minerals, deposited in three main zones: Borate zone, Borax zone and Lithium-borate zone. The basin basement in the north part is dominated by lower Triassic clastic and Paleozoic metamorphic sediments, while to the ...

  • Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry

    Steven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti (2021)
    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 revitalization

  • Optimizacija i planiranje površinskih kopova stohastičkim modelima

    Dejan R. Stevanović (2015-05-29)
    Savremeno rudarstvo izloženo je stalnom trendu pogoršanja uslova poslovanja.Mogućnost ostvarenja ekonomskih i drugih ciljeva rudarskog projektakompromitovana je stalnim pogoršanjem kvaliteta ležišta na kojima se vršieksploatacija, kao i značajnoj dozi neizvesnosti povezane sa geološkim,ekonomskim i tehničkim parametrima proizvodnje. U ovako kompleksnimuslovima poslovanja, matematički modeli sposobni da odgovore značajnimizazovima, odnosno ponude optimalna rešenja kojima se garantuje maksimalnoispunjenje projektovanih ciljeva, nameću se kao neophodnost.Trenutni, konvencionalni pristup optimizaciji i planiranju površinskih kopovazasniva se na algoritmima, razvijenim sredinom prošlog veka čije je opšteobeležje deterministički ...
    površinski kop, planiranje, optimizacija, stohastički modeli, kontrola kvaliteta uglja, neizvesnost.
    ... Science and Technology, vol. 10, str. 323–335. Denby, B. and Schofield, D., 1994, Open pit design and scheduling by use of genetic algorithms. Transactions of the Institute of Mining and Metallurgy, Section A), Vol. 103, str.21-26. Dimitrakopoulos R., 2011, Strategic mine planning under uncertainty, stochastic ...
    ... open-pit optimization. International Journal of Surface Mining Reclamation and Environment, Vol. 2, No. 4, str. 173–179. Dominy S. C., Noppe M. A., Annels A. E., 2002, Errors and Uncertainty inMineral Resource and Ore Reserve Estimation: The Importance of Getting it Right.Exploration Mining Geology, vol ...
    ... the Institute of Mining and Metallurgy, (Section A, Mining Industry), vol. 102, str. A95-A104 Dowd, P, A, Pardo-Igúzquiza, E, 2002, The Incorporation of Model Uncertainty in Geostatistical Simulation, Geographical and Environmental Modelling, Vol.6, str. 147-169. Dowd, P. A. and Onur, A. H., 1992, Optimizing ...

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

    Božo Kolonja, Dinko Knežević, Ranka Stanković, Dejan Stevanović, Detlef Trummer (2016)
    ... does not have to be, while the probability of collisions between stackers and reclaimers is lower than with stockyards arranged in two rows. However, stockyards arranged in two rows enable greater comfort in organizing operations, increasing the number of piles and ensuring larger reserves at the ...
    ... deposit with a simulation of transport- and blending models of mining operation. Beretta, et al (2010) used geostatistical simulation for reducing coal quality attributes variability using properly designed blending piles. These models allow assessing the uncertainty associated with the attributes content ...
    ... can be used to calculate, plan, control and predict the quality of ore being stacked and/or reclaimed with a great degree of accuracy. Robinson (2004) presents mathematical and computer models for the geometry of a stockpile, using both actual grade data and a variogram to describe the input variation ...

  • Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example

    Miloš Marjanović, Biljana Abolmasov, Igor Peshevski, James Reeves, Irena Georgievska (2020)

  • Debris-flow Susceptibility Assessment in Flow-R: Ribnica River Case Study

    Ksenija Micić, Miloš Marjanović, Biljana Abolmasov (2024)
    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 ...
    tečenje drobine, Flow-R, procena podložnosti, empirijski model

  • 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

  • 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
    ... e ambiguity, and cannot be expressed quantitatively, so the model of integration, based on the theory of fuzzy sets, has been developed. Theories of fuzzy logic are specifically used for description and proposition of indicators, i.e., their composition in which prevail uncertainty, indefinitely, ...
    ... able to perform the required function [1], under given conditions and at a specific moment in time, and assuming that the necessary supply is provided (external resources) [2]. Availability may also be expressed as the probability that the system will be ready for use at any (calendar) time, or that ...
    ... be able to perform the required function [1], under given conditions and at a specific moment in time, and assuming that the necessary supply is provided (external resources) [2]. Availability may also be expressed as the probability that the system will be ready for use at any (calendar) time, or that ...

  • Efekti potencijalnog korišćenja postrojenja za preradu otpadnih voda kao energetskih izvora u sistemima daljinskog grejanja u Srbiji

    Dejan Ivezić, Marija Živković, Aleksandar Madžarević (2019)
    Системи даљинског грејања постоје у 57 градова и општина у Србији и доминантно користе фосилна горива. У овим урбаним срединама су изграђени, или се планира градња система за пречишћавање отпадних вода. У раду је размотрена (са еколошког и енергетског аспекта) могућност додатног, енергетског коришћења топлоте пречишћене воде у СДГ, применом топлотних пумпи. На примеру Шапца је извршено поређење постојећег СДГ са системом који би применом топлотних пумпи искористио енергетски потенцијал система за пречишћавање отпадних вода. Добијени индикатори су послужили ...
    системи даљинског грејањa, постројења за пречишћавање отпадних вода, топлотне пумпе
    ... Greenhouse Gas Inventories, 2006, https://www.ipcc-nggip.iges.or.jp/public/2006gl/ [8] IPCC, Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories, 2001, https://www.ipcc-nggip.iges.or.jp/public/gp/english/ [9] Министарство заштите животне средине Републике Србије ...
    ... https://www.eea.europa.eu/data-and-maps/indicators/energy-efficiency-and-energy-consumption-2/assessment-2 https://www.eea.europa.eu/data-and-maps/indicators/energy-efficiency-and-energy-consumption-2/assessment-2 https://www.ipcc-nggip.iges.or.jp/public/2006gl/ ...
    ... научна конференција ТОПС 2019 [6]Europian Environment Agency,Energy efficiency and energy consumption in the household sector, 2015,https://www.eea.europa.eu/data-and-maps/indicators/energy- efficiency-and-energy-consumption-2/assessment-2 [7] IPCC, 2006 IPCC Guidelines for National Greenhouse ...

  • Determining the Groundwater Balance and Radius of Influence Using Hydrodynamic Modeling: the Case Study of the Groundwater Source “Šumice” (Kikinda, Serbia)

    Dušan Polomčić, Dragoljub Bajić, Jelena Zarić (2015)
    A groundwater flow model was developed to simulate groundwater extraction from the public water supply source of the City of Kikinda. The hydrodynamic model includes the municipal groundwater source of Kikinda (Šumice and the Jezero Well), but also an extended area where there are groundwater sources that provide water supply to three factories: (MSK, TM and LŽT - Kikinda). Hydrodynamic modeling, based on the numerical method of finite differences will show the groundwater balance of the sources in the ...
    Water supply, Aquifer, Flow, Groundwater regime, Numerical modeling, Particle tracking
    ... The 200-day period reflected the travel time to the wells and represented the third and widest sanitary protection zone [13]. Particle tracking can be used for various purposes. The backward particle tracking method with an uncertainty analysis of porosity, applying a Monte Carlo approach, with ...
    ... times from recharge to discharge areas along identified flowpaths [15]. Using a standard numerical flow and transport code and a technique based on adjoint theory, and combining forward-in time and backward-in time transport modeling, it is possible to determine the impact of potential contaminant ...
    ... comprise Pliocene and Quaternary sediments. The base of the Quaternary sediments is made up of shallow lacustrine sediments of the Upper Pliocene. They are built of sandy siltstone, gravelly and sandy siltstone, dark gray siltstone and organogenic silty sands. Carbonaceous interbeds and organic matter ...

  • 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 (2023)