Претрага
277 items
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Determining the Impact of Cutting Elements State on the Bucket–Wheel Excavator Vibration and Energy Consumption
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, ...Filip Miletić, Predrag Jovančić, Miloš Milovančević, Miloš Tanasijević, Stevan Đenadić. "Determining the Impact of Cutting Elements State on the Bucket–Wheel Excavator Vibration and Energy Consumption" in Journal of Vibration Engineering & Technologies, Springer (2022). https://doi.org/10.1007/s42417-022-00482-3
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Life Cycle Assessment of Individual Wood Biomass Heating Systems in Households
The use of solid fuels (wood biomass and coal) for heating of households continues to be common practice within European countries. Solid fuel combustion in households contributes more than 46% to total emissions of fine particulate matter. In this study, a life-cycle assessment (LCA) of firewood-based and pellet-based heating systems is performed. These two systems represent two different types of individual wood biomass heating systems. In the case of the firewood-based heating systems, it is analyzed a typical stove ...... ISO 14000 and it deals with the comparative LCA of HSs throughout all stages of HSs’ lifetime. The exact data on the structure of energy use for space heating by the fuel and type of HS are not available in Serbia. For that reason, the inventory data of each phase of the LC process is collected through ...
... Households 431 3.1 Case study details For a detailed LCA study, it is obligatory to consider the operational period of HSs for a specific living space. The operating energy consumption of HSs is calculated by using data from the available Energy Agency of the Republic of Serbia’s (AERS) report on ...
... value) of each fuel. It is assumed that the period of use of the appliances is 20 years. Table 1 shows the estimated annual amount of fuels needed for space heating [18] in the case of firewood and wood pellet HSs for a typical flat [17]. The adopted efficiency data are based on [17] because manufacturers ...Boban Pavlović, Dejan Ivezić, Marija Živković. "Life Cycle Assessment of Individual Wood Biomass Heating Systems in Households" in 5th International Scientific Conference ”Conference on Mechanical Engineering Technologies and Applications” COMETa2020, East Sarajevo, 2020, University of East Sarajevo, Faculty of Mechanical Engineering East Sarajevo (2020)
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Crystallography and Surface Oxidation of Stoichiometric Arsenopyrite from Šumadija-Kopaonik Pb-Zn/Polymetallic Ore District (Serbia)
Ivana Jelić, Aleksandar Pačevski, Aleksandar Kremenović, Aleš Šoster, Andreja Šestan, Janez Zavašnik (2023)The behaviour and stability of arsenopyrite largely depend on its crystal structure, but studies of crystallography and structural defects are scarce. For clarification, we investigated a series of natural arsenopyrite crystals from the polymetallic Pb-Zn-(±Cu,Ag,Au,Sb,Bi,W) Šumadija-Kopaonik ore district (Serbia) by powder X-ray diffraction (XRPD). Among them, samples from the Drenjak gold mineralisation showed near-stoichiometric FeAsS composition and were further investigated by conventional and high-resolution transmission electron microscopy methods. TEM revealed abundant planar crystallographic defects and epitaxial surface oxide layer ...Inorganic Chemistry, Condensed Matter Physics,General Materials Science, General Chemical Engineering, crystal structure, FeAsS, oxidation, TEM, XRPD... arsenopyrite is closely related to the orthorhombic marcasite [10] and tetragonal rutile [9]. Our observations confirm a monoclinic crystal system, space group P2; /c [9]. As observed on the experimental Kikuchi lines image (Figure 4b,c), the whole pattern symmetry is m (Figure 4a,b), and the arsenopyrite ...
... the TEM analysis closely resembles the marcasite prototype structure (Figure 4d). We interpret the occurrence of the forbidden hk0 reflections (space-group absences) observed in the experimental SAED (Figure 4a) to occur due to twinning [10]. Figure 4. (a) SAED pattern indexed for arsenopyrite ...
... , with the corresponding, (b) CBED pattern showing Kikuchi lines. (c) Simulated SAED and CBED (threshold 55%, intensity factor 1%, squares are space group absences). (d) Arsenopyrite crystal structure in the same orientation left to right: ball-stick model, coordination tetrahedra model, Fe-tetrahedra ...Ivana Jelić, Aleksandar Pačevski, Aleksandar Kremenović, Aleš Šoster, Andreja Šestan, Janez Zavašnik. "Crystallography and Surface Oxidation of Stoichiometric Arsenopyrite from Šumadija-Kopaonik Pb-Zn/Polymetallic Ore District (Serbia)" in Crystals, MDPI AG (2023). https://doi.org/10.3390/cryst13020278
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Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites
Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković (2023)To investigate the effect of synthesis procedure and sintering temperature on the functional properties of perovskite/spinel ceramics, BaTiO3/CoFe2O4 composites were prepared by thermal decomposition, coprecipitation, and microemulsion method, and sintered at 1150°C and 1300°C. The phase composition and morphology of as-prepared powders as well as sintered ceramics were thoroughly examined by X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM) coupled with electron dispersive spectroscopy (EDS). The dielectric and ferroelectric measurements were performed in detail. Generally, the ...Marija Šuljagić, Aleksandar Kremenović, Ivan Petronijević, Adis Džunuzović, Miljana Mirković, Vladimir Pavlović, Ljubica Anđelković. "Understanding the effect of synthesis and sintering temperature on the functional properties of barium titanate/cobalt ferrite composites" in Science of Sintering (2023). https://doi.org/10.2298/SOS220512013S
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Conversion of land areas after coal mine closure and reclamation
Otkopavanje uglja površinski i podzemno praćeno je degradacijom zemljišta, promenom formiranja predela i izmenom flore i faune. Od velikog značaja je razvoj novih naučno utemeljenih pristupa obnovljanje antropogeno poremećenih predela zasnovanih na formiranju rekultivacionih i rudarskih tehnologija. Apsolutno je neophodno obezbediti sveobuhvatno kvalitetno očuvanje zemljišnih i vodnih resursa i odrediti rekultivisano zemljište za novu namenu. U ovom članku je dat pregled najpopularnijih metoda rekultivacije zemljišta i mogućnosti rekultivacije zemljišta nakon završetka rekultivacije i zatvaranja rudnika uglja.... considering the topographical changes of the green space that would directly affect the degradation of agricultural lands. Predictions of the effects on the environment are very important and present the concern in the sense of the loss of surface area and space for living. The study on the environment has ...
... same time further harmonizing it with the relevant EU legislation [10]. Basic decisions on the national level are sometimes contradictory and leave space for discussion about the energy strategy in Europe. On the one side, the coal phasc-out gathers pace. Most EU countries have announced the national ...Radmila Gaćina, Bojan Dimitrijević, Sanja Bajić. "Conversion of land areas after coal mine closure and reclamation" in 9th International conference mining and environmental protection MEP 23 Proceedings, Sokobanja, 24-27.05.2023., Belgrade : University of Belgrade - Faculty of mining and geology (2023)
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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 ...... secondary technical limitations, such as temperature limitations, operator training, availability of the main source of energy, fluid, surface conditions (space limitations, noise, visibility, safety), and additional limitations at the bottom of the well (high gas-liquid ratio—GLR, scale, sand, corrosion) ...Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković. "Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic" in Energies, MDPI AG (2020)
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Kristalne strukture Cs2HoSi4O10F i Cs2TmSi4O10F
... were determined by single-crystal X-ray diffraction analysis. They represent mutually isostructural compounds which crystallize in the orthorhombic space group Pnma with following unit cell parameters: a = 22.3809 (7), b = 8.8686 (3), c = 11.9827 (4) V = 2378.41 (14) 3, Z = 8 (for Cs2HoSi4O10F compound) ...
... dobijena su dva jedinjenja do tada nepoznatog hemijskog sastava - Cs2HoSi4O10F i Cs2TmSi4O10F, u obliku monokristala. Jedinjenja su sintetisana metodom rasta kristala iz visokotemperaturnog rastvora (Tmax = 1373 K) koriste i REE2O3 (REE = Ho, Tm), SiO2 i CsF kao polazne suptance. Kristalne strukture ...Predrag Dabić, Sabina Kovač, Aleksandar Kremenović. "Kristalne strukture Cs2HoSi4O10F i Cs2TmSi4O10F" in XXVII konferencija Srpskog kristalografskog društva, Kragujevac, 16-17. septembar 2021., Beograd : Srpsko kristalografsko društvo (2021)
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Strategic Environmental Assessment in the Application of Preventive Protection for Wind Farm Noise—Case Study: Maestrale Ring Wind Farm
Determining the spatial position of wind turbines is the initial and most important phase in the development of a wind farm project. In this sensitive phase, all potential problems that may arise in the later stages of project development should be prevented by means of spatial and urban planning instruments. This makes it possible to achieve maximum use of the potential of wind in a particular space and, thus, fulfil the technical and economic requirements of the project while ...Energija,energetski inženjering i elektroenergetska tehnologija,obnovljivi izvori energije, održivost i životna sredina,električni i elektronski inženjering,kontrola i optimizacija,inženjering... while respecting the capac- ity of the space and involving the public in all phases of developing and adopting the SEA. In this context, SEA makes a significant contribution to the decision-making process with regard to the future development of a particular space [15] and it is an important instru- ...
... prevented by means of spatial and urban planning instruments. This makes it possible to achieve maximum use of the potential of wind in a particular space and, thus, fulfil the technical and economic requirements of the project while re- specting the goals of environmental protection in that same area ...
... Plan of the Maestrale Ring wind farm). Criteria Rank Description Magnitude of Impact Significant −3 Significantly burdens the capacity of the space (increase in noise levels at recep- tors over 4 dB compared to Limit values for the noise indicators (LVNI) Greater −2 Disturbs the environment ...Boško D. Josimović, Aleksandar Cvjetić, Božidar Manić. "Strategic Environmental Assessment in the Application of Preventive Protection for Wind Farm Noise—Case Study: Maestrale Ring Wind Farm" in Energies, MDPI AG (2021). https://doi.org/10.3390/en14196174
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Improvement of geodatabase queries within GeolISS
Ranka Stanković (2008)... can be part of a relational table as a normal column and processes using a multitude of operators. The space required for storage and sharing of vector data is usually much smaller than the space required for raster data. Another advantage of vector data is that they can be easily updated and maintained ...
... vector data model to represent reality. Raster data sets record a value for each point in the area of interest, which may require more storage space than the representation in vector format that stores only the Ranka Stanković 66 necessary data. Vector data can be displayed as vector graphics ...Ranka Stanković. "Improvement of geodatabase queries within GeolISS" in Review of the National Center for Digitization, Beograd : Faculty of Mathematics, Belgrade (2008)
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Rift sequence stratigraphy and its contribution to source rock understanding – Serbian part of Pannonian Basin
Filip Anđelković, Dejan Radivojević (2018)... sional mechanism (Matenco and Radivojević, 2012). The analysis of syn-kinematic reflectors demonstrates that normal faulting migrates in time and space and took place on a wide Miocene time interval (roughly 20–5.5 Ma) (Matenco and Radivojević, 2012). The most prolific source rocks in Serbian part ...Filip Anđelković, Dejan Radivojević. "Rift sequence stratigraphy and its contribution to source rock understanding – Serbian part of Pannonian Basin" in CBGA, Salzburg, Austria, Septembar 10-13, 2018, Bulgarian Academy of Science (2018)
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Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept
Improvements of Machine Learning-based landslide prediction models can be made by optimizing scale, customizing training samples to provide sets with the best examples, feature selection, etc. Herein, a novel approach, named Cross-Scaling, is proposed that includes the mixing of training and testing set resolutions. Hypothetically, training on a coarser resolution dataset and testing the model on a finer resolution should help the algorithm to better generalize ambiguous examples of landslide classes and yield fewer over/underestimations in the model. This ...Uroš Đurić, Miloš Marjanović, Zoran Radić, Biljana Abolmasov. " Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept" in Engineering Geology , Elsevier (2019). https://doi.org/10.1016/j.enggeo.2019.05.007
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Prilog rešavanju problema istraživanja antiklinalnih struktura primenom potencijalnih električnih metoda
Ranko Mužijević (1961)Ranko Mužijević. Prilog rešavanju problema istraživanja antiklinalnih struktura primenom potencijalnih električnih metoda, Beograd:Rudarsko Geološki Fakultet, 1961
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Određivanje zbijenosti starog komunalnog otpada
Bez obzira na savremene tretmane komunalnog otpada u svetu, u Srbiji je i dalje najčešći vid odlaganja na komunalne deponije, pa zbijanje otpada predstavlja jednu od ključnih faza formiranja deponije. Na ovaj način znatno se smanjuje zapremina otpada, ubrzava proces degradacije i produžava radni vek deponije. Zbog toga su geotehničke karakteristike komunalnog otpada prilikom zbijanja, veoma bitne kako u fazi projektovanja tako i u fazi izgradnje deponije i optimizacije prostora. Tu se pre svega misli na maksimalnu suvu zapreminsku ...Jovana Janković, Dragoslav Rakić, Irena Basarić Ikodinović, Tina Đurić. "Određivanje zbijenosti starog komunalnog otpada" in Konferencija Otpadne vode, komunalni čvrsti otpad i opasan otpad, 16-18.06.2021., Beograd : Udruženje za tehnologiju vode i sanitarno inženjerstvo (2021)
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Geotehnički efekti razaranja komunalnog otpada različitim postupcima zbijanja
Jovana M. Janković Pantić (2022)Odlaganje otpada na komunalne deponije predstavlja osnovni način zbrinjavanja otpada u Srbiji. Kako bi se prostor za deponovanje materijala racionalno koristio potrebno ga je svakodnevno zbijati sa unapred definisanom količinom vode koja se dodaje. Dobro zbijeni komunalni otpad zauzima manju zapreminu i omogućuje sigurnije skladištenje, pa je korisno prethodno laboratorijski odrediti parametre zbijanja: maksimalnu suvu zapreminsku težinu (dmax) i optimalnu vlažnost (wopt). U Srbiji do sada nisu određivani parametri zbijanja, dok je u svetu primenjivana standardna metoda (Proktorov opit) ...Jovana M. Janković Pantić. Geotehnički efekti razaranja komunalnog otpada različitim postupcima zbijanja, Beograd : [J. Janković Pantić], 2022
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BaTiO3/NixZn1−xFe2O4 (x = 0, 0.5, 1) Composites Synthesized by Thermal Decomposition: Magnetic, Dielectric and Ferroelectric Properties
Marija Šuljagić, Ivan Petronijević, Miljana M. Mirković, Aleksandar Kremenović, Adis Džunuzović, Vladimir B. Pavlović, Aleksandra Kalezić-Glišović, Ljubica Andjelković (2023)To investigate the influence of spinel structure and sintering temperature on the functional properties of BaTiO3/NixZn1−xFe2O4 (x = 0, 0.5, 1), NiFe2O4, ZnFe2O4, and Ni0.5Zn0.5Fe2O4 were in situ prepared by thermal decomposition onto BaTiO3 surface from acetylacetonate precursors. As-prepared powders were additionally sintered at 1150 °C and 1300 °C. X-ray powder diffraction (XRPD) and scanning electron microscopy (SEM) coupled with electron dispersive spectroscopy (EDS) were used for the detailed examination of phase composition and morphology. The magnetic, dielectric, and ...ferroelectric, dielectric properties, magnetic properties, titanate/ferrite composites, phase composition... used to develop magnetoelectric muhltiferroic materials. This is due to its unique dielectric properties in the tetragonal phase with the P4mm space group [30-—33]. In order to design novel multiferroic composites based on barium titanate, ferrites are one of the ideal candidates due to their ...
... barioferrite-like phases were formed. However, spinel and tetragonal BaTiOs phases remain unchanged. The transformation of BaTiOs from P4Amm to P4/mmm space group Was observed at 1300 ?C in all studied cases. Inorganics 2023, 11, 51 3of 19 as-prepared In te ns it y [A rb . un it s] In te ns ...
... Znp,s Fe)Oa samples. Table 1. The phase composition of prepared composites. In parenthesis next to the phase chemical formulae crystal system and space group are presented as well as corresponding, PDF card numbers from the ICDD database. Phase abundances are calculated by the RIR method. Samples ...Marija Šuljagić, Ivan Petronijević, Miljana M. Mirković, Aleksandar Kremenović, Adis Džunuzović, Vladimir B. Pavlović, Aleksandra Kalezić-Glišović, Ljubica Andjelković. "BaTiO3/NixZn1−xFe2O4 (x = 0, 0.5, 1) Composites Synthesized by Thermal Decomposition: Magnetic, Dielectric and Ferroelectric Properties" in Inorganics, MDPI AG (2023). https://doi.org/10.3390/inorganics11020051
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A comparison between ARIMA, LSTM, ARIMA-LSTM and SSA for cross-border rail freight traffic forecasting: the case of Alpine-Western Balkan Rail Freight Corridor
Miloš Milenković, Miloš Gligorić, Nebojša Bojović, Zoran Gligorić. "A comparison between ARIMA, LSTM, ARIMA-LSTM and SSA for cross-border rail freight traffic forecasting: the case of Alpine-Western Balkan Rail Freight Corridor" in Transportation Planning and Technology, Informa UK Limited (2023). https://doi.org/10.1080/03081060.2023.2245389
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Određivanje stabilnosti elemenata u muskovitima hemijskim metodama
Radmila Milojković (1977)Radmila Milojković. Određivanje stabilnosti elemenata u muskovitima hemijskim metodama, Beograd:Rudarsko Geološki Fakultet, 1977
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Poreklo asocijacije Ni, Ag i Sn minerala u polimetaličnom ležištu Rudnik
Rudnomikroskopska, SEM-EDS i LA-ICP-MS ispitivanja rudne mineralizacije iz Pb-Zn-Cu-(Ag) ležišta Rudnik, ukazala su na lokalno prisustvo specifične asocijacije minerala nikla, srebra i kalaja, deponovane u tektonskoj breči, arsenopiritsko-pirotinskim, piritsko-pirotinsko-arsenopiritskim i kvarcno-sulfidnim žicama u harcburgitima. U tektonskoj breči deponovan je polimineralni sulfidni agregat kojeg čine pirotin (50), galenit, sfalerit i halkopirit. Arsenopiritsko-pirotinske žice odlikuje dezintegrisani agregat arsenopirita cementovan sa pirotinom. U piritsko-pirotinsko-arsenopiritskim žicama masivni pirit (50%) prorasta sa arsenopiritom i cementovan je polimineralnim agregatom pirotina, galenita i sfalerita. Minerali nikla, srebra ...Stefan Petrović, Aleksandar Pačevski, Viktor Bertrandson Erlandson, Rade Jelenković. "Poreklo asocijacije Ni, Ag i Sn minerala u polimetaličnom ležištu Rudnik" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
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The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)
... M.R.; Nabipour, M. The effect of step on the hydraulic characteristics of the subcritical free surface flow in conveyance tunnel. Tunn. Undergr. Space Technol. 2012, 28, 212–217. [CrossRef] 7. Hassani, A.N.; Katibeh, H.; Farhadian, H. Numerical analysis of steady-state groundwater inflow into Tabriz ...
... Uromeihy, A.; Sharifzadeh, M. Evaluation of hight lokal groundwater inflow to a rock tunnel by charactization of geological features. Tunn. Undergr. Space Technol. 2011, 26, 364–373. [CrossRef] 9. Chen, Y.F.; Hong, J.M.; Zheng, H.K.; Li, Y.; Hu, R. Evaluation of groundwater leakage into a drainage tunnel ...
... 12. Andjelković, V.; Lazarević, Ž.; Nedović, V.; Stojanović, Z. Application of the pressure grouting in the hydraulic tunnels. Tunn. Undergr. Space Technol. 2013, 37, 165–179. [CrossRef] 13. EN 206-1. European Standardization Committee, Concrete—Part 1: Specification, Performance, Production and ...Marina Čokorilo Ilić, Ana Mladenović, Marina Ćuk, Igor Jemcov. "The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)" in Water, MDPI AG (2019). https://doi.org/10.3390/w11030603
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The correlation of Upper Miocene lithostratigraphic units of the southern part of the Pannonian basin
Filip Anđelković, Dejan Radivojević (2019)... along asymmetric simple shear extensional mechanism. The analysis of syn- kinematic reflectors demonstrates that normal faulting migrates in time and space and took place on a wide Miocene time interval (roughly 20 – 5.5 Ma). The Pannonian Basin System encompasses a number of subdepressions, regions ...
... formacije i člana, a izdvojene su na osnovu litološkog sastava, depozicione sredine, korišćenjem podataka sa terena i iz bušotina, i geofizičkih metoda (reflektivna seizmika i geofizički karotaž). Ovakva korelacija ima veliki značaj za poznavanje kompletnog Sistema Panonskog basena. Pored toga, ...Filip Anđelković, Dejan Radivojević. "The correlation of Upper Miocene lithostratigraphic units of the southern part of the Pannonian basin" in Knjiga sažetaka i radova II Kongresa geologa Bosne i Hercegovine, Laktaši BiH, oktobar 2-4, 2019, Udruženje geologa u Bosni i Hercegovini (2019)