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Упит dcterms_subject_txt:Physical and Theoretical Chemistry

2339 items

  • Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements

    Filip Miletić, Predrag D. Jovančić, Milos Milovančević, Dragan Ignjatović (2020)
    The capacity of the rotor excavator depends largely on the operation of the subsystem for digging. There is a great contribution to the correct and sharp teeth when the capacity is the highest. In the function of time, the teeth become clogged due to abrasive wear, or changes in their geometric shape. To analyze the bucket wheel drive in depend on wear of the cutting elements in this study adaptive neuro fuzzy inference system (ANFIS) approach was implemented. ANFIS ...
    Pogon rotornog točka, habanje, rezni elementi, ANFIS

  • Split-Desktop software for the analysis of fragment size distribution of blasted rock mass

    Milanka Negovanović, Lazar Kričak, Stefan Milanović, Jovan Marković, Nikola Simić, Snežana Ignjatović (2023)
    Drobljenje stena je najvažniji pokazatelj u proceni efekata miniranja pri proizvodnom miniranju u površinskoj eksploataciji. Stepen drobljenja stena ima veliki uticaj na efikasnost daljih operacija utovara, transporta, drobljenja i mlevenja. Optimalno drobljenje stena pri proizvodnom miniranju utiče na smanjenje ukupnih troškova proizvodnje. Stoga je pouzdana procena veličine drobljenja odminirane stenske mase veoma važno pitanje, ne samo u operacijama miniranja, već i u rudarskoj proizvodnji. Za predviđanje distribucije veličine komada odminirane stenske mase postoje različiti empirijski modeli. KUZ-RAM model omogućava ...
    Split-Desktop softver, drobljenje stena, miniranje, analiza, digitalna obrada fotografija

  • Results of comprehensive monitoring activities on Umka landslide, Belgrade, Serbia

    Biljana Abolmasov, Uroš Đurić (2021)
    klizišta, monitoring
    ... Faculty of Mining and Geology, Serbia, biljana.abolmasov@rgf.bg.ac.rs 2University of Belgrade, Faculty of Civil Engineering, Serbia, udjuric@grf.bg.ac.rs Background The Umka landslide is the deepest and biggest active landslide in the Republic of Serbia and has been investigated and monitored by ...
    ... will be focused on results and experience gained from automated Global Navigation Satellite System (GNSS) monitoring network data, PSInSAR data analysis from Sentinel1 radar satellite images, conventional geodetic monitoring network data and UAV imaging, processing and data analysis in the last six ...
    ... monitoring: automated GNSS monitorong network, geodetic benchmark survey monitoring, UAV imaging with photogrammetric processing and analysis, and PSInSAR data processing and analysis. Common to all implemented monitoring techniques is to measure displacement of the observed points (dx, dy, dz) on the ...

  • Strain partitioning around an indenter during oroclinal bending: kinematics of the Circum-Moesian fault system of the Carpatho-Balkanides

    Nemanja Krstekanić, Liviu Matenco, Uroš Stojadinović, Ernst Willingshofer, Marinko Toljić, Daan Tamminga (2021)
    ... of a foreland-convex orocline, situated in the north and east and a backarc-convexorocline situated in the south and west. The southern orocline of the Carpatho-Balkanides orogenformed during the Cretaceous closure of the Alpine Tethys Ocean and collision of the Dacia mega-unit with the Moesian Platform ...
    ... ing processes, the Carpathianssubduction and Miocene slab retreat in the West and East Carpathians have driven the formationof the backarc-convex oroclinal bending in the south and west. The orocline formed duringclockwise rotation of the Dacia mega-unit and coeval docking against the Moesian indenter ...
    ... South Carpathians and with a large late Oligocene – middleMiocene Circum-Moesian fault system that affected the orogenic system surrounding the MoesianPlatform along its southern, western and northern margins. This fault system is composed ofvarious segments that have different and contrasting types ...

  • Paleomagnetic evidence for post-collisional Miocene clockwise rotation in the Serbian segment of the Vardar Zone and the Danubicum

    Vesna Lesić, Emő Márton, Vesna Cvetkov, Dragana Tomić (2015)

  • New data on Mesozoic Radiolaria of Serbia and Bosnia, and implications for the age and evolution of oceanic volcanic rocks in the Central and Northern Balkans

    Valentina Vishnevskaya, Nevenka Djerić, G.S. Zakariadze (2009)
    Geochemistry and Petrology, Geology

  • Geology of the southern part of the Sava-Vardar zone: new constraints from the Klepa Mts.

    Dejan Prelević, Ana Mladenović, Violeta Gajić, Milena Dunčić, Blažo Boev (2024)
    Tethys closure, Scaglia Rossa, intracontinental basalts
    ... carbonate rocks arc represented by reddish, locally pinkish, or grey, light grey hemipelagic and pelagic biomicrites with rich planktonic and · benthic · foraminiferal associations. and othcr diverse micro- and macrofossil assemblages (calcareous nannoplankton, calcified radiolarians, palynomorphs ...
    ... which encompasses the Dinaric, Carpathian, and Balkan double-verging Alpine orogenic belt, remains a topic of ongoing debate ({1], [2] and references therein). This orogenic system arose from thc closure of the northern branch of the Neotethys Ocean and subsequent collision-related processes. Key ...
    ... unique opportunity to study the nature and timing of the final closure of the Neotethys Ocean. The Klepa Mountains, situated in the central part of North Macedonia, form a block extending: 5-6 km NNW-SSE and 1-2 km WSW-ENE, reaching a hecight of 1150 m a.s.l. and serving as a prominent landmark in ...

  • Upper Cretaceous scaglia type limestone from Klepa Mts. (North Macedonia) - sedimentology and biostratigraphy

    Violeta Gajić, Milena Dunčić, Ana Mladenović, Dejan Prelević (2024)
    The research area is located in the central part of North Macedonia, in the area of the Klepa Mts. Based on sedimentological, micropaleontological and biostratigraphical investigations of samples from both the east and west side of the Klepa Mts., sedimentary rocks of the Upper Creaceous age are determined. During the latest Cretaceous, this area was dominated by the sedimentation of dominantly carbonate rocks with variable amounts of clastic components. From the tectonic point of view, investigated area belongs to the ...

  • Negative Impact of Backwater Levels of Danube River and its Tributaries to the Groundwater Regime in Meliorated Riverside Areas

    Predrag Pajić, Uroš Urošević, Dušan Polomčić, Milan Dimkić (2016)
    This paper describes updated calculation methodology of Danube backwater impact, occurred as a consequence of “Đerdap I” hydropower plant operation, onto the meliorated riverside areas. This methodology is based on hydrodynamic analysis of groundwater regime (size, duration, level and inflow changes) and quantification of melioration areas impairment which is caused by “Đerdap I” hydropower plant operation. By comparing the groundwater regime elements, obtained by variant hydrodynamic calculation in mathematical models for natural – not backed up and actual – ...
    HPP ''Djerdap 1'', backwater influence, groundwater regime, hydrodynamic analysis, melioration area, drainage system, additional energy engagement

  • Application of Expansive Mortars for the Formation of Artificial Screens During Blasting in Urban Areas

    Milanka Negovanović, Lazar Kričak, Stefan Milanović, Nikola Simić, Jelena Majstorović (2024)
    During construction of buildings in urban areas, sometimes there is a need to blast solid rock mass in the immediate vicinity of the surrounding buildings. In that case, the aim is not only to increase the efficiency of blasting, but also to reduce harmful effects of ground vibration induced by blasting. At the same time, it is very important to protect the buildings located in the safe zone from the blast site as well as remaining rock mass around ...
    expansive mortar, artificial screens, pressure, rock breaking, building foundation

  • A contribution to the knowledge of facial diversity of Badenian sediments in the Belgrade area

    Filip Anđelković, Dejan Radivojević (2018)
    baden, Beograd, facije, facijalna raznovrsnost, sedimenti
    ... erates  (on  Kalemegdan  and  in Rakovica  stream)  and  poorly  cemented  sandstones  and  sands  (type  locality  is  in  Rakovica  stream).  The  conglomerates  contain  numerous  Ostrea  shells  and  represent  a  basal  series.  According to Anđelković M. and Anđelković J., they mark the second ...
    ... composed of Mesozoic  sediments, ophiolites  and ophiolitic mélange, Cretaceous  to Paleogene  flysch  sediments  and  Lower Miocene  continental  sediments.  The  diversified  basin  basement  and  tectonic  processes during the Badenian led to the horizontal and vertical facial changes. Badenian sediments are  ...
    ... „Leitherkalk“  (Gruber,  1988)  or  „Leitha  limestones“)  and  Rakovica  clastic  sedi‐ ments (sands and conglomerates). There are two additonal facies in the Belgrade area, Višnjica clays and  Konjarnik schlier, but they have limited exposure and were inaccessible at the time of field exploration.  Th ...

  • The final closure of the Vardar Ocean: paleomagnetic, AMS and structural results

    Emö Márton, Marinko Toljić, Vesna Lesić, Vesna Cvetkov (2020)
    ... folded during the Upper Cretaceous and Paleogene and the paleomagneticsignals, which exhibit smeared distribution close to the present N, are of post-folding age. TheAMS foliation and bedding planes are sub-parallel, thus the deformation must have been weak.Fold axes and AMS lineations are roughly N-S oriented ...
    ... recently published and new paleomagnetic, AMS results in combination withstructural observations will be presented from Upper Cretaceous sediments and Oligocene–Lower Miocene igneous rocks representing the areas bordering the Sava zone from the westernand eastern sides, respectively and from the upper ...
    ... of the flanking areas and the general NE-SW orientation of thecompressional stress field outside of the zone. Acknowledgement. This work was financially supported by the National Development andInnovation Office of Hungary, project K 128625 and by the Ministry of Education and Science of theRepublic ...

  • Evidence for Badenian marine transgression in Belgrade (Serbia)

    Filip Anđelković, Dejan Radivojević (2019)
    ... Tašmajdan limestones, Višnjica clays and Konjarnik schlier (Anđelković M., 1987; Anđelković, M.&Anđelković, J., 1997; Anđelković F. & Radivojević, 2018). Of these, clastics (conglomerates, sands and sandstones) and limestones (mostly subreefal) have the greatest extent and palaeogeographic significance ...
    ... Mediterranean is the cause for the partial isolation and fall of salinity (Rögl, 1999). REFERENCES Anđelković, M. 1987. Geology of the wider Belgrade area – Geology and geodynamics. Institute for regional geology and palaeontology, Faculty of Mining and Geology, p. 428 (in Serbian) Anđelković, M., Anđelković ...
    ... Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs Evidence for Badenian marine transgression in Belgrade (Serbia) Filip Anđelković1 and Dejan Radivojević1 1University ...

  • A Knowledge-Based Approach to Mine Ventilation Planning in Yugoslav Mining Practice

    Nikola Lilić, Ivan Obradović, Ranka Stanković (2002)
    Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full understanding and use of the obtained results require the involvement of an experienced specialist in the ventilation field. The solution was found in the creation of a hybrid system INVENTS, whose knowledge base represents a formalization of the expert knowledge in the mine ventilation field. In this paper, we ...
    ... structure and user interface. 1. Introduction The methodology of mine ventilation planning and design in contemporary Yugoslav mining theory and practice differs substantially from the traditional approach. Novel approaches take full advantage of the possibilities offered by computer hard- ware and software ...
    ... ward and easy manipulation of input data and control over different components of the problem-solving process. Through the interface the system also offers suggestions and recommendations to the user for the improvement of the overall performance of the mine ventilation system (Figs. 12 and 13). ...
    ... Design and Development (Macmillan Publishing Company, New York, 1994). 3. J. S. Kowalik (ed.), Coupling Symbolic and Numerical Computing in Expert Systems (North-Holland, Amsterdam, 1986). 4. N. Lilic, R. Stanković and I. Obradović, A hybrid system for mine ventilation systems planning and analysis ...

  • Dating of alluvial sediments from borehole at the lower course of the Sava river and indications of the connection between their genesis and climate changes in the Pleistocene

    David Mitrinović, Jelena Zarić, Oliver Anđelković, Gyorgy Sipos, Dušan Polomčić, Milan Dimkić (2019)
    This paper analyses the way in which Pleistocene climate change and glaciations in Dinaric Mountains was reflected in the deposition of alluvial sediments in the Sava river Valley, using a case study of Belgrade Groundwater Source (BGS), the largest and most downstream alluvial water supply source along the Sava river. A stratigraphic analysis of the Quaternary sediments from two boreholes on this site, based on sediment dating, lithological members identification, grain size distribution analysis was performed. Comparison with the ...
    Pleistocene, Alluvial deposits, Climato-lithostratigraphy, Sava river, Belgrade groundwater source, Luminescence

  • Development of the Cost-Based Model for Monitoring the Lifetime of the Earth Moving Machines

    Ugljesa Bugarić, Milos Tanasijević, Stevan Djenadić, Dragan Ignjatović, Ivan Janković (2022)
    This paper presents the model for the identification of reference points on the lifetime curve of engineering systems. This curve commonly represents the increase and decline of failure in relation to time. A direct correlation between failure rate and costs is assumed in this paper, therefore, statistical and empirical analysis of costs provided reference points. This approach is used for positioning stages of the engineering system’s lifetime with a minimal number of failures and costs, regardless of whether these ...
    Electrical and Electronic Engineering,Industrial and Manufacturing Engineering, Control and Optimization, Mechanical Engineering, Computer Science (miscellaneous), Control and Systems Engineering

  • Structural and microstructural study of brookite based TiO2 nanocomposites with carbon black (C)

    Aleksandar Kremenović, Mirjana Grujić-Brojčin, Nataša Tomić, Maja Šćepanović (2022)
    Structural and microstructural properties of TiO2-based nanocomposites with carbon black (C), synthesized by sol-gel-hydrothermal method, have been studied by XRPD and Raman scattering. Detailed size-strain analyses of XRPD and Raman scattering results are presented in order to investigate the influence of C content on brokite and anatase phase formation. The XRPD size-strain analyses have resulted in reliable structure and microstructure results for both anatase and brookite and their relative abundance ratio has been refined by Rietveld method. The brookite ...

  • Хазард од клизишта у Србији у 21. веку

    Biljana Abolmasov (2019)
    клизишта, хазард од клизишта, промене климе
    ... current state and pla Landslides 10(1):103�109. [3] Sendai Framework for Disaster Risk Reduction 2015�2030, UNISDR/GE ICLUX EN5000 1 http://edition.www.unisdr.org [4] Cruden D. M.,Varnes D. J. (1996). Landslide types and processes. I Shuster L. R. (Eds). Landslides, investigations and Mitigation ...
    ... Technical Guidelines and Best Practices related t national initiative for loss reduction, Geological Survey �f Canad 2013. [6] Hungr O., Leroueil S., Picarelli L. (2012). Varnes classification o an update. Proceedings of the 11th International and 2nd American Symposium on Landslides and Engineered Slopes ...
    ... Engineering Geology and the Environm [10] Guzzetti F, Carrara A, Cardinalli M, Reichenbach P. (1999). Lan evaluation: a review of current techniques and their application in a m study, Central Italy. Geomorphology 31:181�216. [11] Crozier M. & Glade T. (2005). Landslide hazard and risk:Issues, Approach ...

  • Palaeoflora of Kamenica (Pranjani Basin, western Serbia)

    Zorica Lazarević, Ljubica Milovanović, Jelena Milivojević, Ivana Vasiljević (2019)
    Palaeofloras of the Paleogene in Serbia are relatively rare, especially in comparison with floras from Neogene sediments. Most Paleogene phytoas sociations from the territory of Serbia existed in a dry and warm climate. The youngest Paleogene phytoassociation originates from the Pranjani Basin (Western Serbia), locality Kamenica. The age of this palaeoflora is determined as Late Oligocene. This fossil plant assemblage is different from other Paleo gene phytoassociations.The palaeoflora from Kamenica is characterized with leaf imprints larger than in other ...
    макрофлора, млађи олигоцен, Прањански басен, Каменица
    ... basin (the village of Kamenica) and it consists of well cemented conglomerates and breccias lying directly over the peridotite-serpentine rock. above them is a sequence of alternating sandstones, con- glomerates and marlstones. Well preserved remains of fossil plants and fish have been found in these sediments ...
    ... elements of temperate climate are very rare, and represented only by a few imprints of Betulaceae and ulmaceae. Based on the taxonomical composition of palaeo- phytoassociation and leaf morphology, it has been inferred that the climate was subtropical and humid during the existence of this plant association ...
    ... the layers of the older horizon. This horizon is composed of sandstones and sands with thin layers of conglomerates, dolo - mitic limestones and shales as well as one interca- lation of tuffits. The third horizon consists of marls and shales (ereMIja et al., 1977). The fossil fish Smerdis minutus (BLaINvILLe) ...

  • Identification of the Best Available Renewable Energy Source for Electricity Production in Serbia

    Boban Pavlović, Dejan Ivezić, Marija Živković (2020)
    Around 2/3 of electricity production in Serbia originates from coal-fired thermal power plants. The most significant domestic coal deposits are lignite deposits, a type of low -quality coal that causes negative health, climate and environmental impacts during the combustion. To reduce those negative impacts on domestic electricity production and to promote environmental awareness, the Serbian Energy Sector Development Strategy and the National Action Plan for Use of Renewable Energy Sources indicate the plan for increasing the share of ...
    Strategija obnovljive energije, Održiva energija, Proizvodnja električne energije, Solarna energija, Biomasa, Hidroenergije, Energija vetra
    ... experts' judgments and availa ble literature. The results of th e FAHP reveal that biom ass has the highest rank among the RES to generate electricity and a s su ch can be characterized as a strategic RES. Wind and hydro energy are ranked second and th ird, respectively, and solar is in the last ...
    ... approach th at consists of econom ic, environmental, technical, and socio-political criteria. Further on, the Fu zzy A nalytical Hierarchy Pr ocess (FA HP) m ethod is u sed for a ssessing four renewables (biom ass, hydro, solar and wind) in regard to the defined criteria. The obtained weights for ...
    ... Source for Electricity Production in Serbia | Boban Pavlović, Dejan Ivezić, Marija Živković | Conference on Sustainable Development of Energy, Water and Environment Systems, Sarajevo, 28.6.-2.7.2020. | 2020 | | http://dr.rgf.bg.ac.rs/s/repo/item/0005061 Дигитални репозиторијум Рударско-геолошког факултета ...