Претрага

Упит dcterms_subject_txt:Severity of failure

2698 items

  • 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
    ... results. Good consistency, both in terms of strength and failure Energies 2021, 14, 3710. https://doi.org/10.3390/en14123710 https:/ /www.mdpi.com/journal/energies Energies 2021, 14, 3710 2 of 20 mode, was provided when a comparison of these three types of information was done [1]. Danial Jahed ...
    ... where an analytic method, along with existing data from physical model tests, was applied to acquire results. Good consistency, both in terms of strength and failure Energies 2021, 14, 3710. https://doi.org/10.3390/en14123710 https://www.mdpi.com/journal/energies https://www.mdpi.com/journal/energies ...
    ... vector of the marker m in the current support configuration. → v (t− 1)—the position vector of the marker m in the previous support configuration. → u (t)—the vector of displacement. N—time of monitoring. Figure 2. Change of the marker position over time. In the xz-coordinate plane, the position of the ...

  • An intelligent hybrid system for surface coal mine safety analysis

    Nikola Lilić, Ivan Obradović, Aleksandar Cvjetić (2010)

  • Concepts for Improving Machine Learning Based Landslide Assessment

    Miloš Marjanović, Mileva Samardžić Petrović, Biljana Abolmasov, Uroš Đurić (2019)
    Katastar klizišta, Podložnost, Hazard, Mašinsko učenje, Uzorkovanje, Validacija

  • Uticaj raspadanja na stabilnost kosina u mekoj stenskoj masi

    Anđela Despotov (2024)
    U radu je opisano ponašanje mekih stenskih masa koje su izložene porecesu raspadanja tokom određenog vremenskog perioda. Meke stenske predstavljaju kritične vrste stenskih masa pošto izazivaju različite probleme tokom izvođenja građevinskih radova. Meke stene mogu biti sedimentne stene, raspadnute metamorfne i magmatske stene. Odlikuju se niskim vrednostima čvrstoće, visokom deformabilnošću, visokom plastičnošću, podložne su dezintegraciji i fizičko-hemijskom raspadanju, odnosno ubrzanom dejstvu površinskog raspadanja usled atmosferskih uticaja.Za klasifikaciju mekih stenskih masa koriste se modifikovane verzije već postojećih klasifikacionih sistema. Jedan ...
    meke stenske mase, dezintegracija, klasifikacioni sistemi, Slake durability test
    ... classifications. US Army Corps of Engineers 8. Bjerrum, L., (1967) Progressive failure in slopes in overconsolidated plastic clay and clay shales. Terzaghi Lecture. J Soil Mech Found Div, ASCE 93(5):3-49 9. Botts, M.E., (1998) Effects of Slaking on the Strength of Clay Shales: A Critical State ...
    ... system for tectonicallydisturbed heterogeneous rock masses, such as flysch. Bulletin of Engineering Geology and the Environment 78 24. Patton FD (1966), Multiple modes of shear failure in rock. In: Proceedings of the 1st ISRM Congress, International society for rock mechanics, Lisbon, Portugal, ...
    ... (1975) A new method for the determination of deformability of rock masses. 2nd ISRM Congress, Belgrade 26. Sousa i dr. (1997), Experimental investigation on the influence of temperature on the mechanical properties of reservoir rocks. International Journal of Rock Mechanics and Mining Sciences, Volume ...

  • Modeliranje tehnoloških procesa u rudarstvu u uslovima nedovoljnosti podataka primenom teorije grubih skupova

    Zoran M. Štirbanović (2015-07-01)
    Rudarstvo, a u okviru njega i priprema mineralnih sirovina, se odlikuje složenošću tehnoloških procesa što je posledica velikog broja uticajnih parametara. Samim tim je potrebno biti veoma obazriv prilikom donošenja odluka u oblasti rudarstva. U cilju što efikasnijeg funkcionisanja procesa, moguće je primeniti različite metode koje služe za pojednostavljenje procesa odlučivanja. Jedna od takvih metoda jeste i teorija grubih skupova. Ona predstavlja relativno novu matematičku teoriju koja je pogodna za razumevanje nepreciznih i nepotpunih podataka kao i za otkrivanje ...
    rudarstvo, priprema mineralnih sirovina, teorija grubih skupova, višekriterijumsko odlučivanje, flotacijsko jalovište, flotacijski kolektor, flotaciona mašina
    ... Denut, The dam breakage of Baia Mare–a pilot study of magnetic screening, Physics and Chemistry of the Earth, Vol.27, 2002, pp. 1371–1376. 82. N. Eriksson, P. Adamek, The tailings pond failure at the Aznalcóllar mine, Spain, Environmental Issues and Management of Waste in Energy and Mineral ...
    ... forecasting the revenues growth rate of the electronic industry, Expert Systems with Applications 37, 2010, pp. 610–617. 22. B. S. Ahna, S. S. Chob, C. Y. Kimc, The integrated methodology of rough set theory and artificial neural network for business failure prediction, Expert Systems with Applications ...
    ... 29. C.-S. Son, Y.-N. Kim, H.-S. Kim, H.-S. Park, M.-S. Kim, Decision-making model for early diagnosis of congestive heart failure using rough set and decision tree approaches, Journal of Biomedical Informatics 45, 2012, pp. 999–1008. 30. Y. S. Chen, Modeling hybrid rough set-based classification ...

  • The influence of Al<sup>3+</sup>ion on porcine pepsin activity<i>in vitro</i>

    Vesna M. Pavelkić, Kristina R. Gopcević, Danijela Z. Krstić, Marija A. Ilić (2008)
    The in vitro effect of Al3þ ions in the concentration range 1.7·1026M–8.7·1023M on pepsin activity at pH 2, via kinetic parameters and its electrophoretic mobility was evaluated. Kinetic study demonstrated the existence of an activation effect of Al3þ at pH 2 on pepsin molecule. Kinetic analysis with respect to concentrations of haemoglobin showed that Al3þ ions increase the maximal velocity (Vmax) and kcat values rather than apparent affinity for substrate (KS) implying the non-competitive nature of activation which indicated ...
    Пепсин, алуминијум, кинетика, активација, електрофоретска мобилност
    ... in patients with renal failure is well documented [16,17]. It has been proposed (with some controversy) as a cofactor in the pathogenesis of Alzheimer"s disease, as well as other neurodegenera– tive pathologies. Accumulated aluminium accelerates process of aggregation of amiloyd beta peptide ...
    ... highest activation of pepsin activity by 191% in the presence of 25 ag AP?/ mL of reaction mixture [25]. As the mechanism of Al'* ions on pepsin activity is not still clear, the objective of this study is to investigate the m oitro influence of different concen- trations of AL'* ions, physiological ...
    ... Activation of pepsin by Al * ions; The intercepts on the abscissa of the primary plot of [Hb]/V against reciprocal of activator concentrations provide the values of Aso used to obtain the plots of 1/Aso against vo/V shown in the inset. B, curve 2) contain characteristic bands of haemo- globin ...

  • Развој модела употребног квалитета помоћне механизације на површинским коповима лигнита

    Драгица Јагодић Крунић (2021)
    Тренутно стање помоћне механизације на површинским коповима лигнита је незадовољавајуће узроковано пре свега старошћу и неблаговременом заменом машима услед чега је расположивост недовољна а трошкови експлоатације и одржавања високи. Тренутно стање и захтеви који се постављају пред ове машине указују на неопходност оптимизације процеса управљања помоћном механизацијом. Одређивање оптималног времена замене и преосталих могућности је најодговорнији управљачки задатак који треба да буде заснован на свеобухватном сагледавању економских, техничких и других узрочно последичних веза. Са економског аспекта гледано треба одржавати ...
    помоћна механизација, употребни квалитет, ефективност, расположивост, сигурност функционисања, ризик, трошкови животног циклуса, фази логика, Монте Карло метода
    ... encompasses the analysis and synthesis of the following indicators: reliability, maintainability, functionality, maintenance support, severity of machine failure (time needed to bring the machine back to its operating condition, the effect of the machine failure on the work environment and its environmental ...
    ... 7-12. [18] Petrovic, D., i dr., Fuzzy Model for Risk Assessment of Machinery Failures, SYMMETRY- BASEL, 2020, vol. 12 br. 4, str. -. [19] Petrovic. D., i dr., Fuzzy expert analysis of the severity of mining machinery failure, APPLIED SOFT COMPUTING, 2020, vol. 94 br., str. -. [20] Dhillon, ...
    ... модел процене ризика може се применити на било који технички систем. Дејан Петровић и др. у раду „Fuzzy expert analysis of the severity of mining machinery failure” [19] дају концепт анализе озбиљности отказа, једног од показатеља ризика. Полазне поставке овог концепта указују на готово свакодневну ...

  • Contribution to the geotechnical classification of municipal waste landfills in Serbia

    Dragoslav Rakić, Irena Basarić, Laslo Čaki, Slobodan Ćorić (2018)
    Management, Monitoring, Policy and Law, Nature and Landscape Conservation, Geochemistry and Petrology, Waste Management and Disposal,Geotechnical Engineering and Engineering Geology,Water Science and Technology,Environmental Chemistry,Environmental Engineering

  • The external aggregation Newton's method for solving nonlinear equations and applications

    Marija Paunović, Dejan Ćebić, Nebojša Ralević (2020)
    Њутнов метод, агрегациона функција, ред конвергенције

  • Laboratory testing of fly ash

    Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić (2016)
    Fly ash is one of the most common waste materials created by burning of coal. It is composed of smaller particles, consisting mainly of aluminosilicate glass, mullite and quartz, which are collected by electrostatic separators (filter) of gaseous products arising from the combustion of coal. This paper presents the pozzolanic properties, mechanical properties, chemical and mineral composition of fly ash obtained in the combustion process in a power plant Nikola Tesla A (PPNT A) with the addition of a ...
    chemical composition, fly ash, mechanical properties, mineral properties, pozzolanic properties, X-ray diffraction
    ... All prepared samples were stored for a while before the failure. The test was performed with three different series of samples: - samples cured in a wet chamber for 7 days, - samples cured in a wet chamber for 28 days, - samples cured in a wet chamber for 112 days. The uniaxila strength is ...
    ... - the modulus of elasticity. The aim of research is to test the possibility of using the fly ash from PPNT A for making elements of road structures (top and bottom layers of the road). 2 Experimental 2.1 Mineral properties of fly ash Mineral properties of samples of fly ash from thermal ...
    ... the addition of a binder hydrated lime and cement. Tests were performed after 7 and 28 days in a humid environment with different amounts of extra binder: - samples without the addition of binders, - a sample with the addition of 2 % of binder, - a sample with the addition of 4 % of binder, - ...

  • Determination of the groundwater-leakage mechanism (binary mixing) in a karstic dam site using thermometry and isotope approach (HPP Visegrad, Bosnia, and Herzegovina)

    Ljiljana Vasić, Saša Milanović, Anita Puskás-Preszner, Laszlo Palcsu (2020)
    Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • Hyperpycnites within the Devonian-Carboniferous flysch of the Carpatho-Balkanides (Kostadinovica, eastern Serbia)

    Miloš Radonjić (2020)
    This study presents new discoveries of vascular plants and the trace fossil Dictyodora liebeana (GEINITZ) from the Devonian–Carboniferous Kučaj-Zvonce flysch of the Carpatho-Balkanides and the implications of this fossil association for its sedimentary setting. The occurrence of the described plant debris in a deep-marine environment indicates the presence of hyperpycnites within the siliciclastic turbidites exposed at the Kostadinovica locality. The sedimentological data and the characteristics of the fossil material support the proposed model in which the sediment was at ...
    Mississippian flora, Dictyodora liebeana (GEINITZ), hyperpycnites, Kučaj-Zvonce flysch, Carpatho-Balkanides
    ... SYVITSKI, 1995). In contrast, remobilization of the sediment by turbidity currents is manifested by brief events (lasting several minutes) that originate on the basin slope due to stability failure of the sediment (MUTTI et al., 2009). The result- ing deposits of both processes reflect their different ...
    ... at an angle of 40 to 50°. Varia- tions of the dip directions of bedding planes and their dip angles are due to the deformed state of the whole unit. Deformational fabrics are composed of a series of cleavages which significantly disrupt the primary sedimentary structures. Development of seve- ral ...
    ... modes of transport was limited by the insufficient quantity of the obtained sedimentological samples. This led to the use of fossils as an in- dicator of hyperpycnal transport. The presented study could be used as a starting point for a more detailed petrological analysis of the provenance of the ...

  • Advancing Sentiment Analysis in Serbian Literature: A Zero and Few-Shot Learning Approach Using the Mistral Model

    Milica Ikonić Nešić, Saša Petalinkar, Mihailo Škorić, Ranka Stanković, Biljana Rujević (2024)
    Ova studija predstavlja analizu sentimenta srpskih starih romana iz perioda 1840-1920, koristeći veliki jezički model (LLM) Mistral za tehniku učenja sa zasnovani na takozvanim "zero" i "few-shot" pokušajima. Glavni pristup uvodi inovacije osmišljavanjem istraživačkih upita (promptova) uključuju tekst sa uputstvom za klasifikaciju bez primera i na osnovu nekoliko primera, omogućavajući jezičkom modelu da klasifikuje osećanja u pozitivne, negativne ili objektivne kategorije. Ova metodologija ima za cilj da pojednostavi analizu osećanja ograničavanjem odgovora, čime se povećava preciznost ...
    zero-shot, few-shot, sentiment, Serbian, Mistral model

  • Rezultati ispitivanja parametara čvrstoće i dinamičkih svojstava mermera i mogućnost njihove korelacije

    Jelena Majstorović-Necković, Vladimir Čebašek, Veljko Rupar (2023)
    Ispitivanja stena kao radne sredine, odnosno materijala sa kojim se gradi, na kome se gradi i u kome se gradi, svojom složenošću zahteva njeno svestrano izučavanje po velikom broju parametara. Zadatak Mehanike stena je da što bolje upozna ponašanje stenske mase i njenu otpornost na dejstvo pritiska, zatezanja i smicanja, kao i dinamičkih svojstava. Poznavanje navedenih parametara i njihova korelacija omogućavaju pouzdaniji izbor parametara za projektovanje danas sve zahtevnijih uslova kako podzemne, tako i površinske eksploatacije. U ovom radu ...
    mermer, jednoosna čvrstoća na pritisak, čvrstoća na istezanje, brzina longitudinalnih elastičnih talasa, korelacija

  • Hronološki pregled razvoja površinske eksploatacije lignita u Srbiji

    Bojan Dimitrijević, Radmila Gaćina, Bogoljub Vučković (2023)
    U ovom preglednom radu dat je istorijski pregled razvoja površinske eksploatacije lignita na teritoriji Srbije, uz kratak osvrt na geološki nastanak i kvalitet i rezerve uglja, kao i mogućnosti korišćenja za dalju upotrebu. Kolubarski, Kostolački i Kovinski ugljeni baseni lignita u Srbiji, ne računajući Kosovsko-Metohijski i Drenički u sastavu AP Kosovo i Metohija po Rezoluciji 1244 UN, su ležišta najrasprostranjenijeg uglja - lignita u Srbiji koji se eksploatiše od druge polovine 20. veka na velikom broju površinskih kopova ...
    površinska eksploatacija ugalja, lignit, Kolubara, Kostolac, Srbija

  • Споменица 1991. – 2015. година: 135 година геологије и 70 година рударства на Универзитету у Београду

    главни и одговорни уредник Душан Поломчић (2016)
    Рударско-геолошки факултет
    ... the purpose of failure prevention. Journal of Engineering Failure Analysis, Vol. 18 (4), pp. 1203–1211. MANESKI, Т., JOVANČIĆ, P., IGNJATOVIĆ, D., MILOŠEVIĆ-MITIĆ, V., MANESKI, М., 2012: Condition and behaviour diagnostics of drive groups on belt conveyors. Journal of Engineering Failure Analysis ...
    ... structure diagnostics on bucket wheel excavator, for the purpose of failure prevention. Journal of Engineering Failure Analysis, 18 (4), 1203–1211. MIODRAGOVIĆ R., TANASIJEVIĆ M., MILEUSNIĆ Z., JOVANČIĆ P., 2012: Effectiveness assessment of agricultural machinery based on fuzzy sets theory. Expert Systems ...
    ... diagnostics on bucket wheel excavator, for the purpose of failure prevention, Journal of Engineering failure analysis, 2011. 85. Abolmasov B., Jovanovski M., Ferić P., Mihalić S.: Loesses Due to Histo- rical Earthquakes in The Balkan Region: overview of publicly available data, Geofizika, 2011. 86. ...

  • Natural two-dimensional pyrophyllite: Nanoscale lubricant, electrical insulator and easily-machinable material

    Borislav Vasić, Radoš Gajić, Ivana Milošević, Žarko Medić, Marina Blagojev, Marko Opačić, Aleksandar Kremenović, Dejan Lazić (2022)
    Pyrophyllite, with the chemical formula Al2Si4O10(OH)2, is a naturally occurring and abundant van der Waals mineral belonging to the group of phyllosilicates. It is very soft, layered crystal used for sculpting and an excellent electrical and thermal insulator aimed for the operation at high pressure and temperature. Here, for the first time, two-dimensional (2D) pyrophyllite obtained by both mechanical and liquid phase exfoliation is presented and investigated at the nanoscale. The layered structure provides low friction coefficient of around ...
    Atomic force microscopy, Insulating properties, Nanofriction and wear, Natural two dimensional materials, Phyllosilicates, Pyrophyllite

  • Tehnologija izrade i opremanje magacina eksploziva za potrebe ležišta bakra

    Aleksandar Milojević (2024)
    Nakon radova otvaranja i početka eksploatacije, rudno telo bakra velikih rezervi zahteva i veliku količinu eksploziva da bi se ostvario zacrtan kapacitet. Samim tim, neophodno je izraditi funkcionalan magacin eksploziva koji će biti pristupačan svim horizontima i koji će moći da ispuni celokupni kapacitet svih horizonata. Obzirom da će se u magacinu skladištiti eksploziv, on mora ispunjavati specijalne uslove kako bi skladištenje bilo bezbedno. Neophodno je isprojektovati magacin tako da ispuni sve zahteve po pitanju količine i načina skladištenja eksploziva, ...
    podzemna eksploatacija, ležište bakra, magacin, eksploziv
    ... uniaxial compressive strength = 9.938 MPa– _—ccC= 42 global strength = 23.859 MPa s |D.O0205 40 'deformation modulus = 18951.58 MPa a |0.502. 381 Failure Enivelope Range: _ 3 Application: Tunneh - Š 34 siglmax|6.0705 —]MPa š 32 UnitWeight|0.023 | MN/m3 5 30 TunnelDepih|540 m Fa Moht-Coulomb Fit ...
    ... 13. 34 Dimenzije prostorije su 3x2,8 m, a debljina sloja torkret betona 0,25 m. X R—A —— ii Young's 5 lntact \ Initial Elastic Poisson's Failure Material m m Dilation |Piezo - |MatenalName |CoPor| glememt | Yype_ |MeđuM| Rato |_ Giterom | Tvpe | Compreššive | ipeak) |iresiduam | *(peak) | ...
    ... 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 ...

  • Konstitutivne zavisnosti komunalnog otpada sa deponija u Srbiji

    Dragoslav Rakić (2013-05-10)
    U disertaciji su prikazani rezultati laboratorijskih ispitivanja uzoraka komunalnogotpada dobijeni u aparatima za direktno smicanje i edometarskim aparatima (jedanedometarski aparat konstruisan je za potrebe ove disertacije). Sva ispitivanja su izvršenana veštački pripremljenim uzorcima, uz uvažavanje preporuka koje se odnose nadimenzije korišćenih aparata i veličinu najvećih frakcija u uzorku (EN 1997-2, ASTM2007-a, 2007-b). Za formiranje uzoraka korišćen je komunalni otpad različite starosti,uzet sa dve deponije u Srbiji (Ade Huje u Beogradu i gradske deponije u Novom Sadu).Interpretacija rezultata dobijenih iz ...
    komunalni otpad, deponija, geotehnička klasifikacija, čvrstoća smicanja,deformabilnost, indeks primarne kompresije, indeks sekundarne kompresije, modelisleganja
    ... (1979), Limit equilibrium for nonlinear failure envelope, Third International Conference on Numerical Methods in Geomechanics, Aachen, 769-777. Maksimović, M. (1989). Nonlinear failure envelope for soils, Journal of Geotechnical Engineering, American Society of Civil Eng., Vol. 115 (4), 581-586. ...
    ... Therzagi shear strength equation) and the nonlinear failure envelope with the logarithmic function and, for the first time for municipal waste, a nonlinear failure envelope was determined with the hyperbolic function. Tests on municipal waste of different age indicated that shear strength is decreasing ...
    ... basis, the functions are recommended in considerations of slope stability and bearing capacity calculations for landfills 10-15 metres high in Serbia. For higher landfills, the hyperbolic failure envelope is recommended. For verification of the compressibility parameters, the relation proposed ...

  • Konstitutivne zavisnosti komunalnog otpada sa deponija u Srbiji

    Dragoslav Rakić (2013-05-10)
    U disertaciji su prikazani rezultati laboratorijskih ispitivanja uzoraka komunalnogotpada dobijeni u aparatima za direktno smicanje i edometarskim aparatima (jedanedometarski aparat konstruisan je za potrebe ove disertacije). Sva ispitivanja su izvršenana veštački pripremljenim uzorcima, uz uvažavanje preporuka koje se odnose nadimenzije korišćenih aparata i veličinu najvećih frakcija u uzorku (EN 1997-2, ASTM2007-a, 2007-b). Za formiranje uzoraka korišćen je komunalni otpad različite starosti,uzet sa dve deponije u Srbiji (Ade Huje u Beogradu i gradske deponije u Novom Sadu).Interpretacija rezultata dobijenih iz ...
    komunalni otpad, deponija, geotehnička klasifikacija, čvrstoća smicanja,deformabilnost, indeks primarne kompresije, indeks sekundarne kompresije, modelisleganja
    ... (1979), Limit equilibrium for nonlinear failure envelope, Third International Conference on Numerical Methods in Geomechanics, Aachen, 769-777. Maksimović, M. (1989). Nonlinear failure envelope for soils, Journal of Geotechnical Engineering, American Society of Civil Eng., Vol. 115 (4), 581-586. ...
    ... Therzagi shear strength equation) and the nonlinear failure envelope with the logarithmic function and, for the first time for municipal waste, a nonlinear failure envelope was determined with the hyperbolic function. Tests on municipal waste of different age indicated that shear strength is decreasing ...
    ... basis, the functions are recommended in considerations of slope stability and bearing capacity calculations for landfills 10-15 metres high in Serbia. For higher landfills, the hyperbolic failure envelope is recommended. For verification of the compressibility parameters, the relation proposed ...