Претрага

Упит dcterms_subject_txt:Structural analysis

752 items

  • 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

  • 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
    ... was 55, 70% of the same class dozers working in the Kolubara mining basin. The analysis covered four different machine manufacturers, and to provide the necessary objectivity in the interpretation of the results of the analysis, the prefix Type (T1, T2, T3, T4) will be used instead of the names of the ...
    ... 55, 70% of the same class dozers working in the Kolubara mining basin. The analysis covered four different machine manufacturers, and to provide the necessary objectivity in the interpretation of the results of the analysis, the prefix Type (T1, T2, T3, T4) will be used instead of the names of the ...
    ... sub-criteria. All the previously mentioned (input) data necessary for the analysis, results of the pair-wise comparison and ranking are presented in Tables 4–18. Because of the calculation complexity of the input data for analysis [33], only the final values of the considered alternatives are given in ...

  • 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

  • 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

  • Дефинисање хидрауличког механизма истицања карстних подземних вода применом биваријантне анализе временских серија

    Вељко Мариновић (2022)
    Bivariate analysis was applied within the cross-correlation in time and the gain function as part of the cross-spectral function in the frequency domain, to the time series of precipitation and discharge of the Oko Bijela and Bosna karst springs in the period 2015-2020. Bivariate analysis showed a very fast reaction of the Oko Bijela spring and a reaction delay at the Bosna spring, which indicate a very weak amortization of the input signal within the Oko Bijela system and ...
    карст, подземне воде, механизам истицања, крос-корелација, спектрална анализа

  • 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
    ... process (AHP) ranking method. The model contains structural decomposition of availability as an indicator quality of service of the engineering system, their independent analysis, and ranking, and finally gives the possibility of composition. Structural definitions of each outcome are given in accordance ...
    ... recommendation for the company management is that the activities on maintenance analysis, operation analysis, weak-points analysis, and life cycle analysis adapt to this model, which effectively provides comparative data analysis. The model is easy to use. It can also be used for other systems, with possible ...
    ... point 3, an availability analysis was obtained based on the time state picture. According to this analysis, availability is the highest for bulldozer B2, which is in accordance with the expert analysis presented here. For the purpose of a more precise comparative analysis of the obtained results, ...

  • The Fuzzy–AHP Synthesis Model for Energy Security Assessment of the Serbian Natural Gas Sector

    Aleksandar R. Madžarević, Dejan D. Ivezić, Miloš L. Tanasijević, Marija A. Živković (2020)
    Natural gas is used for the production of almost 20% of total energy today. The natural gas security of the Republic of Serbia is an urgent strategic, political and security issue. Serbia is one of the most vulnerable countries in Southeast Europe, because it only has one supply route. This study is a contribution to efforts to better understand the factors affecting energy security through the implementation of a new methodology based on the fuzzy–AHP synthesis model for measuring ...
    energetska bezbednost, prirodni gas, fazi AHP, AHP višekriterijumska analiza, fazi teorija
    ... different approach of analysis and assessment of energy security; Section 2 explains the rationale and the principles for modeling energy security with the fuzzy–AHP synthesis model for Symmetry 2020, 12, 908 4 of 42 analysis energy security of the gas sector. This section provides analysis of basic steps ...
    ... also through the fact that there are no needs to build storage. Expert analysis—questionnaires The methodology of analysis of energy scenarios is shown in the next subsection. 2.2. Methodology Steps The methodology of the analysis of the energy scenarios consisted of several basic steps in which it ...
    ... manage imprecise criteria and the possibility of integrating the analysis of qualitative and quantitative factors. Symmetry 2020, 12, 908 3 of 42 1.2. Energy Security and Fuzzy Theory Fuzzy theory finds its purpose in the analysis and modeling of complex systems, starting from the idea that complex ...

  • The subthermal potential of karstic groundwater of Kučaj–Beljanica region in Serbia estimated by the multivariate analysis

    Ljiljana Vasić, Dragana Ž. Živojinovic, Vladana Rajaković-Ognjanović, Huang Fen, Cao Jianhua (2021)
    Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • Analysis of Belt Weigher Accuracy Limiting Factors

    Aleksandrović Snežana, Jović Mihajlo (2011)

  • 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
    ... 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 interests us as authors and ...
    ... Измењено: 2023-10-22 19:38:49 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 Дигитални репозиторијум Рударско-геолошког факултета ...
    ... факултета Универзитета у Београду [ДР РГФ] 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 | 9th International Conference Mining and Environmental Protection ...

  • GIS analysis of dissipation time of landscape in the Devil's city (Serbia)

    Valjarević A., Srećković- Batoćanin Danica, Živković D., Perić, M. (2015)

  • Gate Road Support Deformation Forecasting Based on Multivariate Singular Spectrum Analysis and Fuzzy Time Series

    Luka Crnogorac, Rade Tokalić, Zoran Gligorić, Aleksandar Milutinović, Suzana Lutovac, Aleksandar Ganić (2021)
    Underground mining engineers and planners in our country are faced with extremely difficult working conditions and a continuous shortage of money. Production disruptions are frequent and can sometimes last more than a week. During this time, gate road support is additionally exposed to rock stress and the result is its progressive deformation and the loss of functionality of gate roads. In such an environment, it is necessary to develop a low-cost methodology to maintain a gate road support system. ...
    deformacije podgrade, lasersko skeniranje, višekanalna singularna spektralna analiza, prognoza, klasterisanje fuzzy vremenskih serija
    ... Spectrum Analysis. Phys. D 2010, 239, 1958–1967. [CrossRef] 13. Hassani, H.; Zhigljavsky, A. Singular Spectrum Analysis: Methodology and Application to Economics Data. J. Syst. Sci. Complex. 2009, 22, 372–394. [CrossRef] 14. Hassani, H.; Mahmoudvand, R. Multivariate Singular Spectrum Analysis: A General ...
    ... support deformation monitoring, while the second phase is related to data analysis. To record support deformations over a defined time horizon we use laser scanning technology together with multivariate singular spectrum analysis to conduct data processing and forecasting. Fuzzy time series is applied ...
    ... support deformation monitoring, while the second phase is related to data analysis. To record support deformations over a defined time horizon we use laser scanning technology together with multivariate singular spectrum analysis to conduct data processing and forecasting. Fuzzy time series is applied ...

  • Formative evaluation of e-learning projects with the logical framework approach

    Roberto Linzalone, Giovani Schiuma, Ivan Obradović, Ranka Stanković (2015)
    ... model is to make clearer the system and allows for more explicit analysis of the project through analysis of the components of the system, which is the promise of a ‘‘white box’’ approach. Furthermore, this type of analysis of the inner components and the logic of the system can enable needed ...
    ... benefits it addresses. In order to represent and analyze the mechanisms of the system, and allow an explicit, even prospective analysis, through the analysis of the individual components of the project [22][23], it is necessary to capture the ‘‘transformation processes that turn interventions ...
    ... innovative project, the technology platform is implemented on an experimental basis, and is not relevant the analysis of training needs and the courses to be activated, rather the analysis of the experience of learning of users (students and workers). 5. CONCLUSIONS Kahan and Goodstadt ...

  • Analiza hidrauličke veze između reke Save i podzemnih voda na izvorištu za vodosnabdevanje Obrenovca

    Dragoljub Bajić, Bojan Hajdin, Dušan Polomčić, Vesna Ristić Vakanjac (2022)
    Na izvorištu „Vić bare“ formiranom u aluvijonu Save za vodosnabdevanje Obrenovca u poslednje dve decenije izvedeno je više detaljnih hidrogeoloških istraživanja u cilju utvrđivanja rezervi podzemnih voda i izdvajanja zona sanintarne zaštite. Monitoring podzemnih voda u celoj zoni izvorišta, za potrebe izrade hidrodinamičkog modela, omogućio je i hidrauličku analizu odnosa površinskih voda reke Save i podzemnih voda na izvorištu sa kojeg se trenutno zahvata do 310 l/s vode. U radu su prikazani rezultati korelacione analize, odnosno ispitivanja na ...
    aluvijon, korelaciona analiza, koeficijent determinacije, režim podzemnih voda

  • Hydrodynamic analysis of radial collector well ageing at Belgrade well field

    Đorđije Božović, Dušan Polomčić, Dragoljub Bajić, Jelena Ratković (2019)
    The origin and effect of hydraulic resistances on the rate of ageing of radial collector wells are identified through numerical hydrodynamic analysis. The research includes hydrodynamic modeling of one such well with new laterals at Belgrade well field. The performance of the laterals is aggravated by rapid ageing. The change in the hydraulic parameters of the laterals during the first decade of operation is analyzed through simulations of the groundwater regime with realistically specified geometries and hydraulics of the ...
    Colmation, Incrustation, Groundwater modeling, MODFLOW–USG, Connected Linear Network Process

  • XRD and SEM analysis of urinary stones

    Miljević Miljana, Rosić Aleksandra (2010)

  • Phase and demographic statistical analysis of urinary stones

    Miljević Miljana, Rosić Aleksandra (2011)

  • Time series analysis of Saraw spring - SE of Sulaimaniya (Iraqi Kurdistan region)

    Ali S.S., Stevanović Zoran (2010)

  • Ore Microscopy Analysis Methods In Mineral Concentration Processis.

    Tomanec Rudolf, Lazić Predrag, Gaćina R, Bajić S. (2013)

  • Analysis of thermo-electrical characteristics of mining cables

    Aleksandrović Snežana, Damnjanović Vesna (2015)