Претрага
541 items
-
Fuzzy expert analysis of the severity of mining machinery failure
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 ...Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković. "Fuzzy expert analysis of the severity of mining machinery failure" in Applied Soft Computing, Elsevier BV (2020). https://doi.org/10.1016/j.asoc.2020.106459
-
Properties of fly ash and slag from the power plants
This paper describes the physical, chemical and mineral properties of ash and slag, which were taken from thermal power plants Nikola Tesla A, Nikola Tesla B, Kostolac A and Kostolac B. The knowledge of the mineralogical material composition is important because the type of minerals directly determines the properties of the fly ash and slag and their possible application. Laboratory tests showed that ash and slag samples consist of the following minerals: amorphous materials, quartz, feldspar, mullite, melilite, cristobalite, ...fly ash, slag, physical composition, chemical composition, mineral composition, X-ray diffraction method... SRPS B.H8.359 (1973): Methods of analysis of coal and coke – Determination of chem- ical composition of fuel ash – General requirements. SRPS B.H8.360 (1973): Methods of analysis of coal and coke – Determination of silica (SiO2) in ash from solid fuels. SRPS B.H8.361 (1973): Methods of analysis of coal ...
... SRPS B.H8.362 (1973): Methods of analysis of coal and coke – Determination of ferric oxide (Fe2O3) in ash from solid fuels. SRPS B.H8.363 (1973): Methods of analysis of coal and coke – Determination of tita- nium oxide (TiO2) in ash from solid fuels. SRPS B.H8.364 (1973): Methods of analysis of coal ...
... SRPS B.H8.365 (1973): Methods of analysis of coal and coke – Determination of cal- cium oxide (CaO) in ash from solid fuels. SRPS B.H8.366 (1973): Methods of analysis of coal and coke – Determination of mag- nesium oxide (MgO) in ash from solid fuels. SRPS B.H8.367 (1973): Methods of analysis of coal ...Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić. "Properties of fly ash and slag from the power plants" in Geologia Croatica, Zagreb : Croatian Geological Survey (2016). https://doi.org/10.4154/gc.2016.26
-
Determination of Mechanical Properties of Altered Dacite by Laboratory Methods
This paper presents a methodology for determining the uniaxial and triaxial compressive strength of heterogeneous material composed of dacite (D) and altered dacite (AD). A zone of gradual transition from altered dacite to dacite was observed in the rock mass. The mechanical properties of the rock material in that zone were determined by laboratory tests of composite samples that consisted of rock material discs. However, the functional dependence on the strength parameter alteration of the rock material (UCS, intact ...... determined based on the Marinos and Hoek [9] and Marinos [10] practical methods (Figure 16). The previous conclusion indicates that the application of these practical methods for estimating the σci has certain limitations and that both methods overestimate the values of intact UCS σci. On the other hand, the ...
... Dacite by Laboratory Methods Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Determination of Mechanical Properties of Altered Dacite by Laboratory Methods | Veljko Rupar ...
... the present study significantly correlates to the values determined according to practical methods given by Marinos and Hoek [9], and Marinos [10] (Figure 17). Therefore, applying both of these practical methods for constant mi estimation is justified, so in this way, one can obtain a realistic estimation ...Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović. "Determination of Mechanical Properties of Altered Dacite by Laboratory Methods" in Minerals, MDPI AG (2021). https://doi.org/10.3390/min11080813
-
Annotation of the Serbian ELTeC Collection
Ovaj rad predstavlja takozvano izdanje nivoa 2 kolekcije tekstova SrpELTeC razvijene u okviru aktivnosti Radne grupe 2 – Metode i alati COST akcije CA 16204 (Distant Reading for European Literary History) i njene specifikacije šeme. Izdanje nivoa 2 je nastavak izdanja nivoa 1, koje se koristi kao ulaz za morfosintaksičke i NER anotacije romana. Srpska obrada nivoa-2 je navedena kroz potrebne korake, uključujući metode i alate koji se koriste u tom procesu. Neki statistički podaci iz srpske kolekcije nivoa ...udaljeno čitanje, literarni korpus, tagiranje, prepoznavanje imenovanih entiteta, lematizacija, ELTeCRanka Stanković, Cvetana Krstev, Branislava Šandrih Todorović, Mihailo Škorić. "Annotation of the Serbian ELTeC Collection" in Infotheca, Faculty of Philology, University of Belgrade (2021). https://doi.org/10.18485/infotheca.2021.21.2.3
-
Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja
Ugljevi niskog ranga – ligniti u Republici Srbiji predstavljaju glavnu energetsku sirovinu koja se koristi za proizvodnju električne energije. Rudarstvo u Srbiji doprinosi bruto dodatoj vrednosti sa 1,8% (2020; https://publikacije.stat.gov.rs/). Sagorevanjem ugljeva niskog ranga u termoelektranama generišu se velike količine elektrofilterskog pepela i pepela, koje često predstavljaju jedan od izvora zagađenja životne sredine usled sadržaja toksičnih elemenata. Dalja upotreba produkata sagorevanja zavisi od njihovog sastava i sadržaja toksičnih mikroelemenata. Svakodnevno sagorevanje lignita u termoelektranama uslovljava konstantan monitoring potencijalno toksičnih ...Branko Kostić, Dejan Prelević, Sabina Kovač, Ksenija Eraković, Dragana Životić. "Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
-
Indexing of textual databases based on lexical resources: A case study for Serbian
In this paper we describe an approach to improvement of information retrieval results for large textual databases by pre-indexing documents using bag-of-words and Named Entity Recognition. The approach was applied on a database of geological projects financed by the Republic of Serbia in the last half century. Each document within this database is described by metadata, consisting of several fields such as title, domain, keywords, abstract, geographical location and the like. A bag of words was produced from these ...... is based on the input of keywords, single or multi-word units (MWU), that can be combined into Boolean expressions. In addition to general search which goes through all fields in the relevant tables, the search can also be performed using specific criteria. For example, if the user chooses the criterion ...
... is used for document ranking. The users express their information need by selecting the criteria and enter- ing keywords, where they can add any number of criteria, of the same or different type. The criteria are linked by conjunction and when there are more keywords within one criterion a disjunction ...
... results are ranked on the basis of weight factors assigned to individual fields in the function of search criteria. Given the information available in the database, it is possible to add criteria and fine-tune the ranking output based on the number of occurrences of a keyword or phrase and the sum of ...Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović. "Indexing of textual databases based on lexical resources: A case study for Serbian" in Semantic Keyword-based Search on Structured Data Sources : First COST Action IC1302 International KEYSTONE Conference, IKC 2015, Coimbra, Portugal, September 8-9, 2015. Revised Selected Papers, Springer (2015). https://doi.org/10.1007/978-3-319-27932-9_15
-
Depth estimation of archeological objects using Euler 3D deconvolution of magnetic data
Vesna Cvetkov, Ilija Vasiljević, Mirko Petković. "Depth estimation of archeological objects using Euler 3D deconvolution of magnetic data" in 5. Hrvatski geološki kongres. Abstract Book 5th Croatian Geological Congress, Hrvatski geološki institut (2015)
-
Korelacija magnetnog susceptibiliteta i sadržaja metala u flotacijskom jalovištu
Procena metala u rudama, jalovištu i zemljištu se tradicionalno određuje hemijskim metodama kao što su Rengen fluorescentna analiza (XRF), Instrumentalna neutronska aktivaciona analiza (INAA) i Masena spektrometrija induktivno spregnute plazme (ICP-MS). Neke od pomenutih metoda su veoma zahtevne i skupe, te se nametnula potreba ka traženju jeftinijeg alata za brzu procenu prisustva pojedinih metala. Tokom poslednjih nekoliko decenija, mnoge studije su pokazale da su magnetna merenja dovoljno osetljiva da detektuju magnetni signal feromagnetnih materijala, a samim tim i metala ...Filip Abramović, Vesna Cvetkov, Aco Ilić, Dragana Životić. "Korelacija magnetnog susceptibiliteta i sadržaja metala u flotacijskom jalovištu" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
-
Hybrid Model for Optimisation of Waste Dump Design and Site Selection in Open Pit Mining
Aleksandar Doderovic, Svetozar-Milan Doderovic, Sasa Stepanovic, Mirjana Bankovic, Dejan Stevanovic (2023)Waste management is an unavoidable technological operation in the process of raw material extraction. The main characteristic of this technological operation is the handling of large quantities of waste material, which can amount to several hundred million cubic metres. At the same time, this operation must comply with all administrative and environmental standards. Therefore, optimising waste rock management (particularly haulage and dumping) has the potential to significantly improve the overall value of the project. This paper presents a hybrid ...Aleksandar Doderovic, Svetozar-Milan Doderovic, Sasa Stepanovic, Mirjana Bankovic, Dejan Stevanovic. "Hybrid Model for Optimisation of Waste Dump Design and Site Selection in Open Pit Mining" in Minerals, MDPI AG (2023). https://doi.org/10.3390/min13111401
-
Using Lexical Resources for Irony and Sarcasm Classification
The paper presents a language dependent model for classification of statements into ironic and non-ironic. The model uses various language resources: morphological dictionaries, sentiment lexicon, lexicon of markers and a WordNet based ontology. This approach uses various features: antonymous pairs obtained using the reasoning rules over the Serbian WordNet ontology (R), antonymous pairs in which one member has positive sentiment polarity (PPR), polarity of positive sentiment words (PSP), ordered sequence of sentiment tags (OSA), Part-of-Speech tags of words (POS) ...... as a binary classification problem with classes of ironic and non-ironic statements. In the paper [27] comparison of Naive Bayes (NB) and Decision Trees (DT) methods used to classify tweets into ironic and non-ironic, showed that the results achieved by DT method measured by the F1 measure were better ...
... Linguistics (COLING). 1269–1278. [30] Bianka Trevisan, Melanie Neunerdt, Tim Hemig, Eva-Maria Jakobs, and Rudolf Mathar. 2014. Detecting Irony Patterns in Multi-level Annotated Web Comments. In Workshop Proceedings of the 12th KONVENS 2014. 34–41. [31] Aline A Vanin, Larissa A Freitas, Renata Vieira, and Marco ...
... balanced and imbalanced set of tweets, respectively). Findings re- ported in [3] depict binary classification of tweets using Random Forest (RF) and DT methods, where the best result (F1 = 80%) was achieved using the RF method over the corpus of #humor tweets, while authors in [6] used Support Vector Machine ...Miljana Mladenović, Cvetana Krstev, Jelena Mitrović, Ranka Stanković. "Using Lexical Resources for Irony and Sarcasm Classification" in Proceedings of the 8th Balkan Conference in Informatics (BCI '17), New York, NY, USA, : ACM (2017). https://doi.org/
-
Laboratory testing of fly ash
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... surface of ash. International standard ASTM C 311 describes the procedures of chemical and physical methods for characterization of fly ash, and standard ASTM C 618 provides chemical and physical criteria related to classification. Based on the international standard ASTM C 618, chemical conditions that ...
... (2013), pp. 725-739. DOI: 10.2298/JSC120716125I [4] SRPS B.H8.359. Methods of analysis of coal and coke - Determination of chemical composition of fuel ash - General requirements. // Belgrade (1973). [5] SRPS B.H8.360. Methods of analysis of coal and coke - Determination of silica (SiO2) in ash ...
... ash from solid fuels. // Belgrade (1973). [6] SRPS B.H8.361. Methods of analysis of coal and coke - Determination of barium oxide (BaO) in ash from solid fuels. // Belgrade (1973). [7] SRPS B.H8.362. Methods of analysis of coal and coke - Determination of ferric oxide (Fe2O3) in ash from solid ...Miloš Šešlija, Aleksandra Rosić, Nebojša Radović, Milinko Vasić, Mitar Đogo, Milovan Jotić. "Laboratory testing of fly ash" in Tehnički vijesnik (2016). https://doi.org/10.17559/TV-20150317171035
-
Application of Thermal Imaging in Surface Mining
Milanka Negovanović (2022)Termalno snimanje se sve više koristi u rudarskoj industriji kao jedan od dijagnostičkih alata za praćenje određenih proizvodnih procesa, kao i stanja opreme i mašina. Predstavlja nedestruktivnu i beskontaktnu metodu ispitivanja koja omogućava rano otkrivanje problema, planiranje održavanja sa minimalnim kvarovima, sprečavanje neplaniranih poremećaja, posmatranje materijala u nepristupačnim ili opasnim područjima i poboljšanje bezbednosti i produktivnosti. Termalno snimanje koristi specijalizovane termalne kamere sa unutrašnjim detektorima koji identifikuju veoma male temperaturne varijacije i proizvode sliku tog nevidljivog infracrvenog ili toplotnog ...Termalno snimanje, nedestruktivne metode testiranja, površinska eksploatacija, termalne kamere, rudarske operacijeMilanka Negovanović. "Application of Thermal Imaging in Surface Mining" in 15th International Conference OMC 2022, Zlatibor, 12-15th October 2022, Jugoslovenski komitet za površinsku eksploataciju (2022)
-
Metodologija proračuna sanacije klizišta šipovima
Klizišta u Srbiji, u najvećem broju slučajeva, jako zavise od geoloških uslova u terenu i svako klizište ima svoje specifičnosti koje moraju da se odrede geotehničkim istraživanjima. Stoga su u radu prvo prikazane osnovne karakteristike klizišta u Srbiji, kao i postupci njihovog istraživanja. Zatim su prikazani proračuni sanacije klizišta vertikalnim šipovima. Metodologija proračuna je složena, jer podrazumeva interakciju klizišta i stabilizirajućih šipova. Prilikom određivanja bočne otpornosti tla oko šipova koristi se metoda Brinč Hansena koja uzima u obzir trodimenzionalne ...klizišta, geotehnička istraživanja, bočna nosivost šipova, interakcija klizišta i šipa, analiza stabilnostiSlobodan Ćorić, Dragoslav Rakić, Stanko Ćorić, Dušan Berisavljević. "Metodologija proračuna sanacije klizišta šipovima" in V simpozijum društva za Geotehniku R. Severne Makedonije, ISRM Specialized Conference, Društvo za Geotehniku Severne Makedonije (2022)
-
Assessments of effects of implementation of strategic plans for development of Belgrade District heating system
The district heating system (DHS) is one of the key elements of the Belgrade energy system. Overview of the current state and basic characteristics of the DHS are presented in this paper. The focus is on the planned development of DHS and on the analyses of effects of realization of measures and projects defined by strategic documents related to DHS which are adopted by city authorities (Development Strategy of DHS and Strategy of Belgrade Development). Two exploratory scenarios were ...Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Miodrag Grujić. "Assessments of effects of implementation of strategic plans for development of Belgrade District heating system" in Sustainable Cities and Society, Elsevier BV (2020). https://doi.org/10.1016/j.scs.2020.102304
-
Просторна анализа епикарста у оквиру карстног система источног дела Суве планине
Епикарст представља највиши део стенске масе који је изложен карстификацији, при чему су главне карактеристике епикарста акумулирање подземне воде и стварање услова за формирање концентрисаних токова у подини ове зоне. У досадашњој пракси истраживања епикарста углавном су коришћене индиректне методе: даљинска детекција, анализа хидрограма карстних врела, хидрохемијске и изотопске анализе, па чак и опити трасирања, док је са друге стране јако мали број истраживача изучавао епикарст директним теренским истраживањима. У раду je приказана иновирана методологија истраживања епикарста, која користи ...Бранислав Петровић, Зоран Стевановић, Вељко Мариновић, Снежана Игњатовић. "Просторна анализа епикарста у оквиру карстног система источног дела Суве планине" in XVI српски симпозијум о хидрогеологији са међународним учешћем, Универзитет у Београду, Рударско-геолошки факултет (2022)
-
Analiza uslova formiranja oticaja reke Resave (istočna Srbija)
Vesna Ristić Vakanjac, Marina Mitrašinović, Veljko Marinović, Saša Milanović, Ljiljana Vasić, Branislav Petrović, Petar Vojnović (2023)Reka Resava zbog veličine sliva i količine vode koju daje Velikoj Moravi predstavlja jednu od najznačajnijih njenih desnih pritoka. U okviru njenog sliva jasno se izdvajaju gornji, geomorfološki raznolik deo sliva, koji je uglavnom izgrađen od karbonatnih sedimenata, i donji deo koji pripada Velikomoravskom basenu. Proticaj reke Resave se beleži u profilima Manastir Manasija koji kontroliše gornji deo sliva u iznosu od 358 km2 i Svilajnac, koji se nalazi na oko 3.5 km pre njenog ušća i koji kontroliše ...Vesna Ristić Vakanjac, Marina Mitrašinović, Veljko Marinović, Saša Milanović, Ljiljana Vasić, Branislav Petrović, Petar Vojnović. "Analiza uslova formiranja oticaja reke Resave (istočna Srbija)" in Zbornik radova III Kongresa geologa Bosne i Hercegovine sa međunarodnim učešćem, Neum, 21-23.9.2023. , Ilidža : Udruženje/udruga geologa u Bosni i Hercegovini (2023)
-
Modeliranje i simulacija energetske tranzicije u sektoru domaćinstava
Boban S. Pavlović (2022)Aktuelnu energetsku tranziciju odlikuje ubrzanje procesa dekarbonizacije energetskih sistema, unapređenje energetske efikasnosti, razvoj čistijih tehnologija baziranih na obnovljivim izvorima energije i održivije korišćenje prirodnih resursa. Da bi se napravio ovako krupan zaokret u postojećim energetskim sistemima, osim promene postojećih tehnologija, potrebno je u planiranje energetske tranzicije uključiti i političke, sociološke, ekonomske i ekološke aspekte, a pre svega obrasce ponašanja i donošenja odluka krajnjih potrošača. Predmet istraživanja u disertaciji je energetska tranzicija sektora domaćinstva, preciznije tranzicija u grejanju domaćinstava, imajući u ...energetika, energetska tranzicija, energetsko planiranje, energetsko modeliranje, obnovljivi izvori energije, domaćinstva, ponašanje potrošačaBoban S. Pavlović. Modeliranje i simulacija energetske tranzicije u sektoru domaćinstava, Beograd : [B. Pavlović], 2022
-
The Newton method for solving nonlinear equations based on aggregation operators
Nebojša M. Ralević, Dejan Ćebić (2019)Nebojša M. Ralević, Dejan Ćebić. "The Newton method for solving nonlinear equations based on aggregation operators" in XLVI International Symposium on Operational Research SYM-OP-IS, Kladovo, 15-18.9.2019, Универзитет у Београду (2019)
-
Advantages and Disadvantages of a Parallel and Zigzag Method of Acquisition in Walking Mode in Magnetometric Archeological Research
магнетометријска испитивања, цик-цак и паралелна аквизиција у ходајућем моду, линеарне аномалије, археологија... basic prerequisite for the application of geophysical methods to be successful. The use of iron-based materials during human history allows for the successful application of magnetometry, which is now one of the leading choices of geophysical methods for archaeologi- cal reconnaissance. Archaeology ...
... Figure 1 After the completion of the fi rst three methods of measurement, the same polygon traverses were reoriented by 90°, i.e. in an east-west direction and the next three measurements were performed in the same way as in the fi rst three methods of mea- suring when the orientation was in a north-south ...
... conducted using the following three methods. As with the fi rst measurement, in this case, the data was sampled in a zigzag fashion. However, contrary to the fi rst method, in this case, the data of each profi le was stored in a separate fi le. The last two methods of measurement were carried out ...Mirko Petković, Vesna Cvetkov, Branislav Sretenović. "Advantages and Disadvantages of a Parallel and Zigzag Method of Acquisition in Walking Mode in Magnetometric Archeological Research" in Arheologija i prirodne nauke (2014)
-
Hydrochemical indicators of groundwater flow in the area of “Čukaru Peki” Cu-Au underground mine in eastern Serbia
The physical and chemical properties of groundwater, together with the groundwater levels regime and rock hydraulic properties, are often used to understand and conceptualize the hydrogeological system. Prediction of the influence of mining works on groundwater, and vice versa, is a challenge due to significantly altered groundwater flow patterns in the raw materials exploitation areas in relation to natural conditions. Therefore, multiple parameters are assessed and monitored before and during exploitation to properly characterize and quantify the system for ...Nebojša Atanacković, Vladimir Živanović, Jana Štrbački, Veselin Dragišić, Ivana Cvejić. "Hydrochemical indicators of groundwater flow in the area of “Čukaru Peki” Cu-Au underground mine in eastern Serbia" in 5th IAH CEG conference, Slovenian Committee of International Association of Hydrogeologists - SKIAH (2022)