Претрага

Упит dcterms_subject_txt:stohastički sivi model

817 items

  • Mine ventilation system planning using genetic algorithms

    Nikola Lilić, Ranka Stanković, Ivan Obradović (1997)
    The most common problem in contemporary mining practice related to the planning and analysis of ventilation systems is the optimization of partially regulated air distribution in mine ventilation networks. This paper presents a two step optimization procedure for partly regulated air distribution in mine ventilation networks. The first step is the determination of air distribution in all branches using the well known Hardy-Cross method. In the second step the distribution and parameters of air flow regulators with minimum engaged ...
    coal, lignite, and peat; ventilation systems; coal mining; underground mining; ventilation; mathematical models; design; air flow; optimization; calculation methods

  • Simpson's rule application for experimental determining parameters of rock mass oscillation equation at limestone

    Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Branko Gluščević, Luka Crnogorac (2021)
    By its form, the use of explosives has a destructive character. However, energy of chemical explosives is tamed and perfected in many effects, so that is developed a series of activities which work is unthinkable without the use of explosives. In mining industry, explosives are most commonly used for exploitation in hard rock mass. Thereby, large amounts of explosives can be used, especially for mass blasting. The application of large amounts of explosives gives auspicious techno – economic indicators ...
    working environment, seismic effects of blasting, oscillation velocity, rock mass oscillation equation, Simpson’s rule

  • Pleistocene rhinoceros from Bogovina Cave: the first report of Stephanorhinus hundsheimensis Toula, 1902 (Mammalia, Rhinocerotidae) from Serbia

    Predrag Radović, Miloš Radonjić, Emmanuel Billia (2020)
    Finds of Pleistocene rhinoceros are rare in Serbia, and only one species (the woolly rhinoceros Coelodonta antiquitatis Blumenbach, 1799) has been reported so far. The current paper presents the dental material of an extinct so-called Hundsheim rhinoceros, Stephanorhinus hundsheimensis Toula, 1902 from Bogovina Cave (East ern Serbia). Both the morphological and metric characteristics of the teeth are consis tent with the attribution to S. hundsheimensis. Unfortunately, the rhinoceros material originated from an uncertain geological context, so there is no ...
    rhinoceros, Stephanorhinus hundsheimensis, Serbia
    ... The occlusal surface is smooth and polished (shiny), showing the lingual valley and the postfos- setta, an open medisinus, and a single, quite mas- sive crochet. The protocone, characterised by a pronounced constriction, appears remarkably bul- bous. Unfortunately, the hypocone has been bro- ken off ...
    ... geneza Bogovinske pećine. Zbornik radova Geografskog instituta „Jovan Cvijić“ Beograd, 29:81-103. Pušić, M. and Stevanović, Z. 1994. Hydrodynamic model of Bogovina karst aquifer. Annales Géologiques de la Péninsule Balkanique, 58(2):303-321. Ravazzi, C., Pini, R., and Breda, M. 2009. Reconstructing ...

  • Hydrothermal Synthesized and Alkaline Activated Carbons Prepared from Glucose and Fructose—Detailed Characterization and Testing in Heavy Metals and Methylene Blue Removal

    Sanja Krstić, Milan Kragović, Maja Pagnacco, Vladimir Dodevski, Branka Kaluđerović, Miloš Momčilović, Ivica Ristović, Marija Stojmenović (2018)
    glukoza, fruktoza, аktivni ugalj, hidrotermalni tretman, aktivacija hidroksida, teški metali, metilen plavo
    ... results for MB removal by KOH activated glucose and fructose samples (measured at 664 nm) were then fitted to different kinetic model: pseudo I, pseudo II and Elovich model, which linear forms are given in Equations (1)–(3) [65], respectively: ln qt qe = k1t (1) t qt = 1 k2·q2 e + 1 qe t (2) ...
    ... – – – – – −3 −3 qt = I + kDt1/2 Figure 8. Linear fits of Pseudo II order kinetic model for KOH activated glucose and fructose samples. Table 7. Characteristic parameters of the Pseudo II order kinetic model for MB removal. Kinetic Parameter AC@G–750–N2–1.0–KOH AC@F–750–N2–1.0–KOH qe, exper (mg/g) ...
    ... rate, and to get additional information about binding mechanism of MB on both adsorbents, the intra-particle diffusion model was also applied. The mathematic form of the diffusion model is given in Equation (4) [65]: qt = I + kDt1/2 (4) where qt (mg/g) is adsorbed amount of MB in time t (min), kD (m ...

  • Application of MCDA in the determination of optimal block size for open-pit modelling and mine planning

    Petar Marković, Dejan Stevanović, Milica Pešić Georgiadis, Mirjana Banković (2021)
    The process of creating a geological block model as the basis for a further detailed design and planning of mining operations is a very responsible task. Errors made during this initial process are transferred to all other phases of the mining project. Certainly, one of the most important decisions for the modelling process is the choice of the appropriate size of the blocks that form the model itself. The determination of the optimal block size is not a simple ...
    dimenzije minibloka, višekriterijumska analiza, AHP, modeliranje ležišta, planiranje na površinskim kopovima

  • Ocena zaštitne funkcije povlatnih slojeva izvorišta Jasik (Opština Batočina) primenom GLA metode

    Rastko Petrović, Igor Jemcov, Dušan Polomčić (2014)
    U cilju utvrđivanja rezervi podzemnih voda i analize uslova zaštite u periodu 2012. i 2013. godine, sprovedena su detaljna hidrogeološka istraživanja na području izvorišta Jasik (opština Batočina). Uspostavljen je sistem monitoringa, čiji je rezultat predstavljao prikupljanje detaljnih hidrogeoloških podataka. Za potrebe analize, izrađen je hidrodinamički model, na osnovu koga je simulirano kretanje podzemnih voda, odnosno, utvrđene zone sanitarne zaštite. Pored navedenog, za potrebe utvrđivanja uslova zaštite podzemnih voda, bilo je neophodno utvrditi podložnost aluvijalne izdani izvorišta Jasik zagađenju. Polazeći ...
    Izvorište Jasik, GLA metoda, zaštita podzemnih voda

  • Spatial assessment of the areas sensitive to degradation in the rural area of the municipality Čukarica

    Natalija Momirović, Ratko Kadović, Veljko Perović, Miloš Marjanović, Aleksandar Baumgertel (2019)
    Nature and Landscape Conservation, Soil Science, Agronomy and Crop Science, Water Science and Technology

  • A WebGIS Decision Support System for Management of Abandoned Mines

    Ranka Stanković, Nikola Vulović, Nikola Lilić, Ivan Obradović, Radule Tošović, Milica Pešić-Georgiadis (2016)
    ... well as the site, for example, a pit, a landfill, workshop or plant. Figure 8 shows part of the conceptual data model. More details about model are available in [15] logical data model of Kanakov. 4.2. Development Environment The relational database management system used was PostgreSQL (The PostgreSQL ...
    ... which depends on the number of factors within the AHP analysis. If CR < 0.1 (10%) the model is consistent. According to Sati a deviation of CR up to 0.3 (30%) is tolerated, but if CR > 0.3 (30%) a correction of the model is necessary. Figure 6 shows the factors taken into account when ranking abandoned ...
    ... with KaNaKov to avoid duplication of resources and to ensure that full synergies are achieved. 4. Materials and Methods 4.1. Geodatabase Model The geodatabase model was developed using Unified Modeling Language (UML) and Computer-Aided Software Engineering (CASE) tool Microsoft Visio (Microsoft Corporation: ...

  • Towards Automatic Definition Extraction for Serbian

    Ranka Stanković, Cvetana Krstev, Rada Stijović, Mirjana Gočanin, Mihailo Škorić (2021)
    U radu su prikazani preliminarni rezultati automatske ekstrakcije kandidata za definicije rečnika iz nestrukturiranih tekstova na srpskom jeziku u cilju ubrzanja razvoja rečnika. Definicije u rečniku Srpske akademije nauka i umetnosti (SANU) korišćene su za modelovanje različitih tipova definicija (opisnih, gramatičkih, referentnih i sinonimskih) koje imaju različite sintaksičke i leksičke karakteristike. Korpus istraživanja sastoji se od 61.213 definicija imenica, koje su analizirane korišćenjem morfoloških e-rečnika i lokalnih gramatika implementiranih kao pretvarači konačnih stanja u paketu za obradu korpusa otvorenog ...
    ... definitions are easy to model. The second group consists of “definitions” of some types of proper names, e.g. names of holidays, saints, monasteries, etc. These definitions are similar to the explanations given in encyclopaedias, they are expressed freely, and are difficult to model with local (shallow) ...
    ... language with the aim of accelerating dictionary development. Definitions in the Serbian Academy of Sciences and Arts (SASA) dictionary were used to model different definition types (descriptive, grammatical, reference-based and synonym-based) having different syntactic and lexical features. The research ...
    ... linguistic constructions, for example, noun phrases. A finite state transducer “passes” through the text it analyses to compare a text chunk with the model it represents. In the case of successful recognition, a final state transducer produces some result, which can be a modification of the source text ...

  • Sustainable Modularity Approach to Facilities Development Based on Geothermal Energy Potential

    Nataša Čuković-Ignjatović, Ana Vranješ, Dušan Ignjatović, Dejan Milenić, Olivera Krunić (2021)
    The study presented in this paper assessed the multidisciplinary approach of geothermal potential in the area of the most southeastern part of the Pannonian basin, focused on resources utilization. This study aims to present a method for the cascade use of geothermal energy as a source of thermal energy for space heating and cooling and as a resource for balneological purposes. Two particular sites were selected—one in a natural environment; the other within a small settlement. Geothermal resources come ...
    геотермална енергија, Панонски басен, геотермална каскада, енергетска ефикасност, бањски центри, балнеологија, биоклиматска архитектура, стратегије пасивног дизајнирања, модуларни објекти
    ... for their enclosure to provide extended use throughout the year. Depending on the business model, we can consider this starting model to be not economically demanding and able to serve as a demonstration model to attracting further investment and multiplication in other locations. Author Contributions: ...
    ... they were not further discussed in detail at this stage of the research. Figure 7. Model for modular wellness facilities with optional hospitality and medical facilities. 2.2. Architectural Model—Boundary Conditions and Calculation Methodology Following the principles of modular design, modules ...
    ... formulated architectural model for balneological application based on sustainable and green design strategies, the paper illustrated a possible development concept that could serve as an implementation tool for activation at various locations. The developed architectural model showed good potential both ...

  • Analiza mogućnosti primene tehnologije hvatanja i skladištenja ugljenika (CO2) na objektima Nis-A

    Isidora Veljanoski (2024)
    U ovom radu opisana je primena CCUS tehnologija u kompaniji NIS i na koji način treba da se optimizuje da bi projekat bio rentabilan.U prvom i drugom poglavlju opisani su energetski trendovi i tranzicije, razvojni mehanizmi za regulisanje emisije gasova staklene baste i o ugljen-dioksidu kao hemijskom jedinjenju i šta je to CCUS.U trećem, četvrtom i petom poglavlju je detaljnije opisano izdvajanje, hvatanje, transport i skladištenje ugljen-dioksida.Šesto poglavlje i sedmo poglavlje obuhvataju rešenja za razvoj i realizaciju CCUS projekata ...
    energetski trendovi, ugljen-dioksid, CCUS, izdvajanje, hvatanje, transport i skladištenje CO2, ležište, ekonomija projekta
    ... se direktno utiskuje u bušotinu. [21 45 8.1 Ekonomija potencijalnog projekta Ekonomski model je alat koji se koristi za razumevanje i predviđanje ponašanje ekonomskih elemenata. Ekonomski modeli predstavljaju pojednostavljene verzije stvarnog ekonomskog sistema, koristeći pretpostavke ı ...
    ... procese i interakcije. Ekonomski modeli pomažu u predviđanju efekata ekonomskih odluka, testiranju različitih scenarija, analiziranju tržišnih dinamika i donošenju informisanih odluka u vezi s ekonomskom politikom ili poslovnim strategijama. Ekonomski modeli su neophodni za donošenje informisanih ...
    ... zavise od tačnosti pretpostavki koje su ugrađene u model. KPI (Key Performance Indicators) su kvantitativne karakteristike koje se koriste za merenje uspeha kompanije, projekta ili sektora u odnosu na postavljene ciljeve. U kontekstu ekonomskog modela, KPI omogućava praćenje konkretnih rezultata ...

  • Mafic alkaline metasomatism in the lithosphere underneath East Serbia: Evidence from the study of xenoliths and the host alkali basalts

    Cvetković Vladica, Downes Hilary, Höck Volker, Prelević Dejan, Lazarov Marina (2010)
    Effects of mafic alkaline metasomatism have been investigated by a combined study of the East Serbian mantle xenoliths and their host alkaline rocks. Fertile xenoliths and tiny mineral assemblages found in depleted xenoliths have been investigated. Fertile lithologies are represented by clinopyroxene (cpx)-rich lherzolite and spinel (sp)-rich olivine websterite containing Ti–Al-rich Cr-augite, Fe-rich olivine, Fe–Al-rich orthopyroxene and Al-rich spinel. Depleted xenoliths, which are the predominant lithology in the suite of East Serbian xenoliths, are harzburgite, cpx-poor lherzolite and rare ...

  • Razvoj algoritma fuzzy optimizacije u hidrodinamičkoj analizi za potrebe projektovanja sistema odbrane od podzemnih voda

    Dragoljub Bajić, Dušan Polomčić (2019)
    Sistemi za odbranu od podzemnih voda se koriste za zaštitu hidrotehničkih objekata, priobalja, meliorativnih područja, naselja, rudnika, industrijskih područja, predstavljajući značajne segmente bez kojih bi funkcionalnost ovih objekata i područja bila dovedena u pitanje. Posebno složeni sistemi odbrane od podzemnih voda se karakterišu kod ležišta mineralnih sirovina, imajući u vidu njihovu dinamičnost, koja se ogleda u stalnom širenju ležišta, kao i činjenicu da ova ležišta prodiru duboko u stensku masu različitog strukturnog tipa poroznosti, a time i u podzemne ...
    upravljanje podzemnim vodama, hidrodinamički model, fuzzy logika, trougaoni fuzzy brojevi, znanje eksperta, optimizacija

  • Human factor risk management procedures applied in the case of open pit mine

    Snežana Kirin, Aleksandar Sedmak, Wei Li, Miodrag Brzaković, Igor Miljanović, Ana Petrović, Simon Sedmak (2021)
    Risk management aims to provide a controlled work environment to ensure the safe operation of the high-risk systems. It is a dynamic process which work in a continual state of change. The issue of human factor risk and rules and regulations in open pit mine is a main focus of this paper in order to develop predictive models of behavior of workers in relation to compliance with the procedures and rules. Presented survey was conducted in open pit coal ...
    Upravljanje rizikom, ljudski faktor, bager sa kašikom, metod konačnih elemenata

  • 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
    ... тога што нам омогућава анализу климатских промена из про - шлости Миланковићева теорија служи и као ос - нова за прављење прогнозних климатских модела. Ови модели омогућавају боље разу мевање разлога настанка климатских промена као и значаја и количине утицаја чо века на њих. Миланковић представља савршен ...
    ... validate his continental drift hypothesis. The factors that cause climate changes enable insight to the geological past, but also the possibility to model the climate conditions which await us in the future. Climate change prediction allowed people, as only being aware of its influence, to act preventively ...
    ... до климатских промена омогућили су поглед у геолошку прошлост, али и моделовање климатских услова који нас чекају у будућности. Прављење прогнозних модела климатских промена омогућава људима, као јединим бићима свесним свог утицаја на њих, да делују превентивно и предузму све мере у циљу смањења емисије ...

  • 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
    ... economic, exploitation and survey parameters are the four most important criteria considered in the analysis [9–12]. In order to define the evaluation model, it is necessary to analyse the working machines from different manufacturers but of the same class and under the approximately same conditions. In ...
    ... economic, exploitation and survey parameters are the four most important criteria considered in the analysis [9–12]. In order to define the evaluation model, it is necessary to analyse the working machines from different manufacturers but of the same class and under the approximately same conditions. In ...
    ... contains the alternative choices which are analysed according to the defined criteria and sub-criteria. The number of criteria and sub-criteria in the model is unlimited. On the basis of the defined criteria and sub-criteria the dependency between them and the qualities of the considered alternatives is ...

  • 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

  • Determining the Impact of Cutting Elements State on the Bucket–Wheel Excavator Vibration and Energy Consumption

    Filip Miletić, Predrag Jovančić, Miloš Milovančević, Miloš Tanasijević, Stevan Đenadić (2022)
    Background There are two types of specifc sizes’ measurements. The frst is the measurement of energy consumption in a working technological process, and the second is the measurement of vibration, which is displayed over amplitudes of speed. There is an interplay between these two processes. Increasing the power consumption, the value of the vibration speed amplitudes increases. Purpose The process of the determination of machining parameters was based on minimizing the power consumption and vibration of the cutting tool, ...
    merenje, potrošnja energije, vibracije, radni vek reznog elementa

  • Complex geophysical survey on solving the problem of water loss in the karst terrain reservoir

    Branislav Sretković, Dejan Vučković (2023)
    Geophysical surveys in karst terrain are always a specific challenge. Each of them requires a careful consideration of the problem, specific conditions on the ground, the selection of adequate methods applicable in that specific and unique karst area. But they should have one thing in common: a complex approach and looking at the problem from wider to narrower, with a gradual narrowing of the investigation area, increasing the spatial precision and resolution of the obtained data. On the example of ...

  • Coupling of artificial intelligence methods in the development of hybrid intelligent systems

    Ranka Stanković, Ivan Obradović, Nikola Lilić (2001)
    In this paper we present an approach which couples various artificial intelligence (AI) methods in the solution of complex problems that cannot adequately be solved by a single AI method. We argue that the resulting, hybrid intelligent systems (HIS) can be successfully implemented with the use of available AI software libraries. Different coupling methods are analyzed and a classification of hybrid systems based on the chosen method is given. Two case studies of hybrid systems used in mining engineering ...
    hibridni inteligentni sistemi, spregnuti sistemi, metode veštačke inteligencije, rudarske primene veštačke inteligencije
    ... module for the analysis of gas distribution in the ventilation system. In view of the complexity of the INVENTS system’s global model data structure, which had to model all relevant parameters of complex mine ventilation networks, the design and realization of database was executed in the MSAccess ...
    ... system for analysis of area airpollution load GIS PollutNet AIRPRES Expert system for air pol lution analysis Data model NM-GA prediction Characterization of ECO domain CFD model - Meteorology - Airpollution - Topology Monitoring Fig. 3 Structure of a hybrid system for analysis of area ...
    ... a software package that enables mine ventilation simulation in underground exploitation of ore deposits. The global structure of the mathematical model for ventilation simulation in mine ventilation networks, transformed into the SimVent software package is composed of the following modules: 1) ...