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Упит dcterms_subject_txt:Probability and Uncertainty

2335 items

  • Spin activity correlations in driven disordered systems

    Đorđe Spasojević, Sonja Radić, Dragutin Jovković, Sanja Janićević (2022)
    Statistics, Probability and Uncertainty, Statistics and Probability, Statistical and Nonlinear Physics

  • The effect of finite driving rate on avalanche distributions

    Sonja Radić, Sanja Janićević, Dragutin Jovković, Đorđe Spasojević (2021)
    Statistics, Probability and Uncertainty,Statistics and Probability,Statistical and Nonlinear Physics

  • Uticaj geološke neizvesnosti u razvoju rudarskih projekata

    Petar Marković, Dejan Stevanović, Mirjana Banković (2023)
    Rudarstvo je industrija koja se nosi sa različitim vrstama neizvesnosti i rizika zbog svoje prirode i specifičnosti. Neizvesnost u rudarstvu može poticati iz različitih izvora i uticati na različite aspekte rudarskih projekata. Kao jedan od dominantnih faktora, ističe se geološka neizvesnost. Geološka neizvesnost igra ključnu ulogu u rudarstvu i može značajno uticati na procenu resursa i rezervi, planiranje eksploatacije, ekonomsku isplativost i upravljanje rizicima. Ova neizvesnost se ne može eliminisati, ali se uz primenu adekvatnih standarda i zakona može ...
    ... its nature and specificity. Uncertainty in mining can come from different sources and affect different aspects of mining projects. Geological uncertainty stands out as one of the dominant factors. Geological uncertainty plays a key role in mining and can significantly affect resource and reserve estimation ...
    ... economic profitability and risk management. This uncertainty cannot be eliminated, but with the application of adequate standards and laws, it can be reduced. Through this paper, the differences in regional and foreign practice from the aspect of categorization of resources and reserves, as well as the ...
    ... s, R., Farrelly, C. T., and Cheuiche Godoy, M. (2002). Moving forward from traditional optimization: Grade uncertainty and risk effects in open-pit design. Transactions of the Institution of Mining and Metallurgy , 3, 82-88. [7] Edwards A.C. (2001). Mineral resource and ore reserve estimation : ...

  • Model of room and pillar production planning in small scale underground mines with metal price and operating cost uncertainty

    Gligorić Zoran, Gligorić Miloš, Dimitrijević Bojan, Grozdanović Ines, Milutinović Aleksandar, Ganić Aleksandar, Gojković Zoran (2018)

  • Uncertainty in open pit optimisation

    Kolonja Božo, Stevanović Dejan, Pešić Georgiadis Milica, Banković Mirjana, Kolonja Ljiljana (2015)

  • Quantification of Uncertainty in Mining Project Related to Metal Price Using Mean Reversion Process and Interval Type-2 Fuzzy Sets Theory

    Gligorić Zoran, Beljić Čedomir, Gluščević Branko (2013)

  • Uncertainty of carbon dioxide emission factor for natural gas

    Živković Marija, Ivezić Dejan, Danilović Dušan, Madžarević Aleksandar (2012)

  • Investigation of quantitative indicators of anisotropy based on longitudinal elastic waves propagation velocities with uncertainty

    Miloš Gligorić, Jelena Majstorović, Suzana Lutovac (2018)
    ... as adverse weather conditions, inaccessible field and inexperience of workers. Due to these problems, sometimes the results of measurements are not so accurate and precise. Presence of vague and imprecise data is the basic indicator of uncertainty. In order to overcome these problems it is necessary ...
    ... anisotropy on the isotropic and anisotropic samples. In order to avoid measurement errors, interval numbers are applied to compute these indicators. Uncertainty of input parameters implies defining a boundaries above these data thereby increasing the flexibility and reliability of the computational ...
    ... WAVES PROPAGATION VELOCITIES WITH UNCERTAINTY Miloš Gligorić1, Jelena Majstorović1, Suzana Lutovac1 Received: May 11, 2018 Accepted: June 15, 2018 Abstract: Almost all of rock masses are more or less anisotropic medium. Foliation, layering, cracking and cleavage are some of the rock attributes ...

  • Application of stochastic models for mine planning and coal quality control

    Dejan Stevanović, Božo Kolonja, Ranka Stanković, Dinko Knežević, Mirjana Banković (2014)
    ... decisions about coal homogenization must deal with uncertainty and variability in coal properties, and with the effect of off-design coal characteristics on power plant performance and cost. According to Shih and Frey [3] sulfur and ash content and heating value are considered as normally distributed ...
    ... (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 as the probability of exceeding the sulfur emission ...
    ... of relevant geological attributes [8, 14]. Fluctua- tions in mining engineering and geochemical attributes of interest are also relevant for mine de- sign and production scheduling. For example, mapping the probability of grades exceeding a limiting threshold within different areas of a deposit can ...

  • A tool for identifying the criticality in the disordered systems with metastable dynamics

    Svetislav Mijatović, Dragutin Jovković, Sanja Janićević, Stefan Graovac, Đorđe Spasojević (2021)
    Физика кондензоване материје

  • Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia

    Dragoljub Bajić, Dušan Polomčić (2014)
    A groundwater control system was designed to lower the water table and allow the pumping sta-tion “Bezdan 1” to be built. Based on a hydrodynamic analysis that suggested three alternative solutions, mul-ticriteria optimization was applied to select the best alternative. The fuzzy analytic hierarchy process methodwas used, based on triangular fuzzy numbers. An assessment of the various factors that influenced the selec-tion of the best alternative, as well as fuzzy optimization calculations, yielded the “weights” of the alternativesand the ...
    groundwater lowering, groundwater management scenario, fuzzy analytic hierarchy process,expert knowledge, triangular fuzzy numbers, linguistic variables
    ... source of uncertainty, because of the transfer of both information and knowledge cou- pled with various uncertainty and imprecision (KOSKO 1993). This is the reason why fuzzy logic systems are distinguished, given that their essence is to handle knowledge that can be highly imprecise and expressed verbally ...
    ... ns of variables and their values produce linguistic statements (expressions), which constitute a bridge between numerical representation of informa- tion on a computer and human thinking. ZADEH (1975) introduced the “linguistic (fuzzy) variable”, which is the value of an uncertainty described by a ...
    ... availability under decision maker uncertainty. Environmental Earth Science, 71 (6): 2559–2572. VAN LAARHOVEN, P.J.M. & PEDRCYZ, W. 1983. A fuzzy extension of Saaty’s priority theory. Fuzzy Sets and Sy- stems, 11: 229–241. ZADEH, L.A. 1965. Fuzzy Sets, Information and Control, 8 (3): 338–353. ZADEH, ...

  • A decision support system for mine project selection under uncertainty using fuzzy topsis technique

    Gligorić Zoran, Beljić Čedomir, Gluščević Branko, Jovanović Saša (2013)

  • Integrated energy planning approach for accelerating energy transition of households

    Boban Pavlović, Marija Živković, Dejan Ivezić (2023)
    The success of energy transition planning depends on several influential and variable factors that need to be considered and tracked in modeling to support policymakers. Expert-based energy models are mainly developed following the assumptions of experts and, in most cases, a limited number of stakeholders. This top-down modeling approach will provide satisfactory results in centrally managed energy sectors (electricity generation and distribution, district heating, etc.), where further decisions could be projected relatively precisely. However, the same approach will not ...
    Energetsko planiranje, Integrisano energetsko modeliranje, Energetska tranzicija, Domaćinstva, Individualno grejanje, LEAP

  • Multi-Criteria Fuzzy-Stochastic Diffusion Model of Groundwater Control System Selection

    Dušan Polomčić, Zoran Gligorić, Dragoljub Bajić, Miloš Gligorić, Milanka Negovanović (2019)
    When considering data and parameters in hydrogeology, there are often questions of uncertainty, vagueness, and imprecision in terms of the quantity of spatial distribution. To overcome such problems, certain data may be subjectively expressed in the form of expert judgment, whereby a heuristic approach and the use of fuzzy logic are required. In this way, decision-making criteria relating to an optimal groundwater control system do not always have a numerical value. Groundwater control scenarios (alternatives) are identified through hydrodynamic ...
    expert judgment, linguistic variables, fuzzy dynamic TOPSIS, hydrogeology, groundwater control system, open-cast mine, geometric Brownian motion

  • Ograničenja primene optimizacionih algoritama u slučaju kopova

    Dejan Stevanović, Mirjana Banković, Milica Pešić Georgiadis, Petar Marković, Dejan Ranković (2020)
    Proces optimizacije površinskih kopova, kao sastavni deo strateškog planiranja, veoma je važan sa stanovišta ostvarivanja maksimalnih efekata proizvodnje. To je složen zadatak koji vrlo često podleže vrlo strogim geometrijskim i drugim praktičnim rudarskim ograničenjima. Ova ograničenja u posebno su izražena na površinskim kopovima uglja, te u značajnoj meri mogu povećati stepen neizvesnosti rudarskog projekta, odnosno izazvati neželjena dejstva u pogledu profitabilnosti poslovanja. Iz tog razloga, veoma je važna primena savremenih optimizacionih alata, koji u značajnoj meri mogu olakšati celokupan ...
    ... complex task that is very often subject to very strict geometric and other practical mining restrictions. These limitations are particularly pronounced in open pit coal mines, and can significantly increase the degree of uncertainty of the mining project, or cause side effects in terms of business ...
    ... reason, it is very important to apply modern optimization tools, which can significantly facilitate the entire optimization process, and also reduce business uncertainty. ! Stevanović Dejan, Univerzitet u Beogradu, Rudarsko-geološki fakultet, Beograd ? Banković Mirjana, Univerzitet u Beogradu, R ...
    ... Plants Through Mine Coal Quality Planning and Control. Thermal Science, 22(1B), pp.721-733, 2017 Benndorf J.: Investigating the variability of key coal quality parameters in continuous mining operations when using stockpiles. Advances in Orebody Modelling and Strategic Mine Planning I. AusiMM, 2011 ...

  • 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

  • Long-term planning methodology for improving wood biomass utilization

    Vladimir Vukašinović, Dušan Gordić, Marija Živković, Davor Koncalović, Dubravka Živković (2019)
    The insufficiently developed forest management system is often followed by undeveloped forest resources supply chain and insufficient institutional support. These cause inefficient usage of fuel-wood as well as huge amounts of unused forest residues. In order to achieve optimal and long-term sustainable utilisation of biomass, an original methodology based on the interaction of mathematical optimization and backcasting approach has been developed. Mathematical optimization is used for both generation and consideration of techno-economic parameters of the forest biomass supply chain. ...
    Long-term planning methodology, Forest biomass, MINLP, Backcasting

  • Probabilistic analysis of anisotropic rock slope with reinforcement measures

    Zoran Berisavljević, Dušan Berisavljević, Miloš Marjanović, Svetlana Melentijević (2023)
    During the construction of E75 highway through Grdelica gorge in Serbia, a major failure occurred in the zone of reinforced rock slope. Excavation was performed in highly anisotropic Paleozoic schist rock formation. The reinforcement consisted of the two rows of micropile wall with pre-stressed anchors. Forces in anchors were monitored with load cells while benchmarks were installed for superficial displacement measurements. The aim of the study is to investigate possible causes of instability considering different probability distributions of the ...
    povratna analiza, tehnika optimizacije, verovatnoća loma, anizotropija čvrstoće

  • Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic

    Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković (2020)
    Artificial lift methods have applications in oil wells where oil production is no longer possible due to natural reservoir energy, so this necessary energy is added by introducing lift methods. In order to achieve optimum production, the selection of an artificial lift method is very important. This paper uses fuzzy logic as a mathematical and conceptual model for selection of the optimal artificial lift method. The outcome or IF-THEN rules, as the central part of the model, is based ...
    mehaničke metode, proizvodnja nafte, fazi logika, donošenje odluka, optimizacija
    ... different processes dominated by uncertainty, multidimensionality, subjectivity, and indeterminacy, and can only be displayed expertly. In order to form the optimization model, it is necessary to reduce the indicated parameters to the same form in the analytical sense and to find a synthesis model. 3 ...
    ... within the reference values (Table 2), and a synthesis part, input parameters, reduced into one. It is evident that the model is rife with uncertainty, indeterminacy, multidimensionality, and relativity. The model must have an inference engine. The new mathematical and conceptual model of optimized selection ...
    ... within the reference values (Table 2), and a synthesis part, input parameters, reduced into one. It is evident that the model is rife with uncertainty, indeterminacy, multidimensionality, and relativity. The model must have an inference engine. The new mathematical and conceptual model of optimized selection ...

  • 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
    ... which can absorb partial indicators of the availability, including their uncertainty, diversity, relativity. In this article, an expert’s fuzzy model is presented to analyze and integrate reliability, maintainability, and functionality of three types of bulldozers that operate at the lignite ...
    ... purchase of new machines. II. AVAILABILITY EVALUATION Availability is the probability that an item will be in an operable and committable state at the start of a mission when the mission is called for at a random time and is generally defined as uptime divided by total time (uptime plus downtime) ...
    ... moment, or during a given interval of time, and assuming the necessary supply is provided (external resources). Availability may also be expressed as the probability that the system will be available at any calendar time, that is, it will be able to operate or to get involved. Availability should not ...