Претрага
358 items
-
Valorization of non-balanced coal reserves in Serbia for underground coal gasification
David Petrović, Lazar Kričak, Milanka Negovanović, Stefan Milanović, Jovan Marković, Nikola Simić, Ljubisav Stamenić (2019)In the name of a better and safer energy future, it is our responsibility to focus our knowledge and activities to save on imported liquid and gas fossil fuels, as well as coal on which energy security of Serbia is based. The rationalization in the use of available energy resources certainly positively affects economy and the environment of a country. This paper indicates motivations for the application of the underground coal gasification process, as well as surface gasification for ...David Petrović, Lazar Kričak, Milanka Negovanović, Stefan Milanović, Jovan Marković, Nikola Simić, Ljubisav Stamenić. "Valorization of non-balanced coal reserves in Serbia for underground coal gasification" in Thermal Science (2019). https://doi.org/10.2298/TSCI190725390P М22
-
Anticipated sulfur dioxide emissions from coal-fired power plants
Aleksandar Madžarevic, Predrag Jovančić, Stevan Đenadić, Filip Miletić, Miodrag Ristović, Miroslav Crnogorac (2024)Southeastern Europe (SEE), which includes Serbia, along with Germany and Poland, is one of the largest producers of solid fuels in Europe. Despite growing environmental concerns, coal, especially lignite, persists and remains the dominant fuel for electricity generation in this region. Concurrently, these power plants emerge as the predominant emitters of pollutants in all the observed states. To conduct a comprehensive analysis, data on major emitters within the European Union were gathered, allowing for a detailed comparison with SEE ...Aleksandar Madžarevic, Predrag Jovančić, Stevan Đenadić, Filip Miletić, Miodrag Ristović, Miroslav Crnogorac. "Anticipated sulfur dioxide emissions from coal-fired power plants" in Thermal Science, National Library of Serbia (2024). https://doi.org/10.2298/TSCI240308167M М23
-
Approximation of the number of roots that do not lie on the unit circle of a self-reciprocal polynomial
Dragan Stankov (2024)We introduce the ratio of the number of roots not equal to 1 in modulus of a reciprocal polynomial Rd(x) to its degree d. For some sequences of reciprocal polynomials we show that the ratio has a limit L when d tends to infinity. Each of these sequences is defined using a two variable polynomial P(x,y) so that Rd(x) = P(x,xn). For P(x,y) we present the theorem for the limit ratio which is analogous to the Boyd-Lawton limit formula ...Dragan Stankov. "Approximation of the number of roots that do not lie on the unit circle of a self-reciprocal polynomial" in The book of abstracts XIV symposium "mathematics and applications” Belgrade, Serbia, December, 6–7, 2024 , Univerzitet u Beogradu, Matematički fakultet (2024) М64
-
Effect of properties of working fluids on the efficiency of a low-temperature Organic Rankine Cycle
Decarbonization of all segments of energy systems, both on the supply and demand side, is one of the main goals of the energy transition. Electricity supply in the future will largely rely on generation from intermittent energy sources: wind and solar. Locally available, non-utilized alternative lowtemperature energy sources as hydro-geothermal wells, and abounded oil and gas wells, have the potential to provide continual energy production over the year. Electricity generation from these energy sources is carried out with working ...Marija Živković, Aleksandar Mijatović, Dejan Ivezić, Boban Pavlović. "Effect of properties of working fluids on the efficiency of a low-temperature Organic Rankine Cycle" in SimTerm Proceedings 2024 - 21st International Conference on Thermal Science and Engineering of Serbia : [proceedings], Niš, 22-25.10.2024., University of Niš, Faculty of Mechanical Engineering, Serbia (2025). https://doi.org/10.5937/SimTerm24159Z М33
-
Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources
Large collections of textual documents represent an example of big data that requires the solution of three basic problems: the representation of documents, the representation of information needs and the matching of the two representations. This paper outlines the introduction of document indexing as a possible solution to document representation. Documents within a large textual database developed for geological projects in the Republic of Serbia for many years were indexed using methods developed within digital humanities: bag-of-words and named ...Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović. "Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources" in Trans. Computational Collective Intelligence - Lecture Notes in Computer Science 26, Springer (2017). https://doi.org/10.1007/978-3-319-59268-8_8 M33
-
Improving efficiency of thermal power plants through mine coal quality planning and control
Главни циљ контроле квалитета угља у рудницима лигнита је снабдевање термоелектрана угљем чији квалитет мора да се креће унутар одређених квалитативних ограничења. Карактеристике угља могу да утичу на ефикасност, поузданост и расположивост како котла тако и јединица за контролу емисије. У овом раду аутори су презентовали интегрисану симулацију рударског процеса као нови приступ у истраживању променљивости калоричне вредности угља приликом експлоатације комплексног лежишта лигнита. Резултати таквог приступа омогућавају драгоцен увид у перформансе континуалног рударског система у смислу контроле променљивости ...Mirjana Banković, Dejan Stevanović, Milica Pešić, Aleksandra Tomašević, Ljiljana Kolonja. "Improving efficiency of thermal power plants through mine coal quality planning and control" in Thermal Science, Vinča Institute of Nuclear Sciences (2018). https://doi.org/10.2298/TSCI170605209B М23
-
Valorization of non-balanced coal reserves in Serbia for underground coal gasification
David Petrović, Lazar Kričak, Milanka Negovanović, Stefan Milanović, Jovan Marković, Nikola Simić, Ljubisav Stamenić (2019)In the name of a better and safer energy future, it is our responsibility to focus our knowledge and activities to save on imported liquid and gas fossil fuels, as well as coal on which energy security of Serbia is based. The rationalization in the use of available energy resources certainly positively affects economy and the environment of a country. This paper indicates motivations for the application of the underground coal gasification process, as well as surface gasification for ...David Petrović, Lazar Kričak, Milanka Negovanović, Stefan Milanović, Jovan Marković, Nikola Simić, Ljubisav Stamenić. "Valorization of non-balanced coal reserves in Serbia for underground coal gasification" in Thermal Science, National Library of Serbia (2019). https://doi.org/10.2298/TSCI190725390P М22
-
Novel Methods in Multiple Criteria Decision-Making Process (MCRAT and RAPS)—Application in the Mining Industry
Multiple criteria decision making (MCDM) is a supporting tool which is widely spread in different areas of science and industry. Many researchers have confirmed that MCDM methods can be useful for selecting the best solution in many different problems. In this paper, two novel methods are presented and applied on existing decision-making processes in the mining industry. The first method is multiple criteria ranking by alternative trace (MCRAT) and the second is ranking alternatives by perimeter similarity (RAPS). These ...Katarina Urošević, Zoran Gligorić, Igor MIljanović, Čedomir Beljić, Miloš Gligorić. "Novel Methods in Multiple Criteria Decision-Making Process (MCRAT and RAPS)—Application in the Mining Industry" in Mathematics, MDPI (Basel, Switzerland) (2021). https://doi.org/10.3390/math9161980 М21а
-
Evaluation of the effects of wastewater heat pump integration into district heating systems by simulation
Dejan Ivezić, Marija Živković, Dimitrije Manić, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović (2023)The integration of wastewater heat pumps (using purified water) in district heating systems is analyzed in this paper. The simulation procedure is proposed to analyze the impacts of stochasticity of purified water temperature and flow to heat pump integration and operation. The analysis includes calculation of the daily and seasonal coefficient of performance, as well as fossil fuel savings and CO2 emission reduction due to wastewater heat pump use. The proposed procedure is implemented for the case study in ...Dejan Ivezić, Marija Živković, Dimitrije Manić, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović. "Evaluation of the effects of wastewater heat pump integration into district heating systems by simulation" in Thermal Science, National Library of Serbia (2023). https://doi.org/10.2298/TSCI220813168I М23
-
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, PyrophylliteBorislav Vasić, Radoš Gajić, Ivana Milošević, Žarko Medić, Marina Blagojev, Marko Opačić, Aleksandar Kremenović, Dejan Lazić. "Natural two-dimensional pyrophyllite: Nanoscale lubricant, electrical insulator and easily-machinable material" in Applied Surface Science, Elsevier BV (2022). https://doi.org/10.1016/j.apsusc.2022.155114 М21а
-
The ‘Umka’ landslide
We present an in-depth landslide map of the ‘Umka’ landslide near Belgrade, Serbia, at a scale of 1:5000. The map delineates elements at risk, primarily buildings and road infrastructure impacted by the landslide displacements of several cm per year, introduced during frequent reactivation stages. The Main map results from a survey of over 350 buildings and more than 7 km of state and local roads. The acquisition techniques included engineering geological field mapping, building survey, and visual interpretation of ...rizik od klizišta, elementi rizika, kartiranje pomoću drona, ispitivanje objekata, geotehnički monitoringUroš Đurić, Dragana Đurić, Miloš Marjanović, Biljana Abolmasov, Ivana Vasiljević. "The ‘Umka’ landslide" in Journal of Maps, Informa UK Limited (2024). https://doi.org/10.1080/17445647.2024.2418580 М22
-
SrpCNNeL: Serbian Model for Named Entity Linking
Ovaj rad predstavlja razvoj modela za prepoznavanje i povezivanje imenovanih entiteta (NEL) sa bazom znanja Vikipodaci za srpski jezik pod nazivom SrpCNNeL. Model je obučen da prepozna i poveže sedam različitih imenovanih tipova entiteta (osobe, lokacije, organizacije, profesije, događaji, demoni i umetnička dela) na skupu podataka koji sadrži rečenice iz romana, pravnih dokumenata, kao i rečenice generisane iz znanja Vikipodataka baza i Leksimirka leksička baza podataka. Dobijeni model je pokazao dobre performanse, postigavši F1 rezultat od 0,8 na test ...Milica Ikonić Nešić, Saša Petalinkar, Ranka Stanković, Miloš Utvić, Olivera Kitanović. "SrpCNNeL: Serbian Model for Named Entity Linking" in Annals of Computer Science and Information Systems, IEEE (2024). https://doi.org/10.15439/2024F8827 М33
-
Two approaches to compilation of bilingual multi-word terminology lists from lexical resources
In this paper, we present two approaches and the implemented system for bilingual terminology extraction that rely on an aligned bilingual domain corpus, a terminology extractor for a target language, and a tool for chunk alignment. The two approaches differ in the way terminology for the source language is obtained: the first relies on an existing domain terminology lexicon, while the second one uses a term extraction tool. For both approaches, four experiments were performed with two parameters being ...Branislava Šandrih, Cvetana Krstev, Ranka Stanković. "Two approaches to compilation of bilingual multi-word terminology lists from lexical resources" in Natural Language Engineering, Cambridge University Press (CUP) (2020). https://doi.org/10.1017/S1351324919000615 М21
-
Solid state synthesis of extra phase-pure Li4Ti5O12 spinel
Фазно чист спинел Li4Ti5O12 са величином честица мањом од 500 nm добијен је реакцијом у чврстом стању из стехиометријске смеше наноанатаса (ТiО2) и Li2CO3 која је претходно активирана механохемијским поступком. Реакција у чврстом стању у потпуности се завршава за само 4 часа на температури од 800 ºC. Уз помоћ XRPD, SEM и TG/DSC анализе испитане су структурне и микроструктурне карактеристике добијеног спинела, механизам реакције између анатаса и Li2CO3, као и термичка стабилност Li4Ti5O12. Реакција започиње разлагањем Li2CO3 на температурама ...дифракција рендгенских зрака, механизам реакције, термичка стабилност, Li4Ti5O12, спинел, фазно чист узоракIvana Veljković, Dejan Poleti, Ljiljana Karanović, Miodrag Zdujić, Goran Branković. "Solid state synthesis of extra phase-pure Li4Ti5O12 spinel" in Science of Sintering, National Library of Serbia (2011). https://doi.org/10.2298/SOS1103343V М23
-
Challenges in using wastewater heat pumps in district heating systems
Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović, Dimitrije Manić (2022)Decarbonization of district heating systems requires ensuring significant amounts of renewable energy available in the proximity of the district heating network. One of the promising solutions is the utilization of purified water from wastewater treatment plants by heat pumps. However, as a heat source, wastewater treatment plants are characterized by annual variability of the flow and temperature of purified water. The consequence is the variability of recoverable heat potential. In this paper, the effect of variability is analyzed for ...Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović, Dimitrije Manić. "Challenges in using wastewater heat pumps in district heating systems" in 20th International Conference on Thermal Science and Engineering of Serbia, Niš, Serbia, October 18 – 21, 2022, Faculty of Mechanical Engineering in Niš (2022) М33
-
The first record of nautiloids (Cenoceras intermedius) from the early Pliensbachian of Rgotina, (Getic nappe, eastern Serbia)
Cenoceras intermedius (J. Sowerby) is one of the most widespread species among the Early Jurassic nautiloid fauna and its geological range still controversial up to the present day. The specimen of Cenoceras intermedius from the sandy bioclastic limestones of Rgotina (Getic nappe of eastern Serbia), is a large half conch representing the phragmocone. Viewing our findings in light of previous results suggests the main morphological changes occurred during the ontogenetic evolution. The coiling starts with a round-square whorl section, ...Cephalopoda, Cenoceras intermedius, ontogenetic changes, geological range, northwestern Neo-Tethys, PliensbachianPaul Țibuleac, Barbara V. Radulović, Marinko Toljić. "The first record of nautiloids (Cenoceras intermedius) from the early Pliensbachian of Rgotina, (Getic nappe, eastern Serbia)" in Historical Biology, Informa UK Limited (2020). https://doi.org/10.1080/08912963.2020.1821003 М21
-
Strategic Environmental Assessment and the precautionary principle in the spatial planning of wind farms – European experience in Serbia
Spatial determination planning is at an initial and very sensitive step in the development of wind farms. On one hand, it is important to maximize the potential of wind in a particular area, and on the other hand, it is important to achieve environmental protection (including the human population and natural heritage) in the same space at the same time. With this in mind, it is important to balance all the requirements that are relevant for reaching the optimal ...Boško Josimović, Aleksandar Cvjetić, Danilo Furundžić. "Strategic Environmental Assessment and the precautionary principle in the spatial planning of wind farms – European experience in Serbia" in Renewable and Sustainable Energy Reviews, Elsevier BV (2021). https://doi.org/10.1016/j.rser.2020.110459 М21а
-
Чији је пример? Анализа лексичких обележја на примерима Речника САНУ
У овом раду поставља се питање: да ли се може утврдити ко је аутор неког текста уколико се анализирају искључиво његова лексичка обележја? Како бисмо покушали да добијемо одговор на ово питање, посматрали смо примере у оквиру речничког чланка појединачне лексеме Речника САНУ, који су забележени у пет томова (и то: I, II, XVIII, XIX и XX). Сваки пример је преузет из неког извора на шта упућују скраћенице, наведене у заградама. Од преко 5.000 понуђених извора, определили смо се ...Бранислава Б. Шандрих, Ранка М. Станковић, Мирјана С. Гочанин. "Чији је пример? Анализа лексичких обележја на примерима Речника САНУ" in Српски језик и његови ресурси, Међународни славистички центар, Филолошки факултет, Универзитет у Београду (2019). https://doi.org/10.18485/msc.2019.48.3.ch13 М51
-
Curcumin nanonization using an alternative small-scale production unit: selection of proper stabilizer applying basic physicochemical consideration and biological activity assessment of nanocrystals
Ines Nikolić, Jelena Antić-Stanković, Dragana Božić, Danijela Ranđelović, Bojan Marković, Dominique Jasmin Lunter, Aleksandar Kremenović, Miroslav Savić, Snežana Savić (2020)As the number of poorly soluble drugs is increasing, nanocrystals have become very interesting due to wide range of application possibilities. Curcumin was used as a model active ingredient in this work. Even though it has many proven positive effects, due to its physicochemical issues, its possibilities have not been fully exploited. The goal of this work was to select optimal conditions for a top-down method for curcumin nanosuspension production, and to perform their comprehensive characterization applying complementary methodologies: ...Ines Nikolić, Jelena Antić-Stanković, Dragana Božić, Danijela Ranđelović, Bojan Marković, Dominique Jasmin Lunter, Aleksandar Kremenović, Miroslav Savić, Snežana Savić. "Curcumin nanonization using an alternative small-scale production unit: selection of proper stabilizer applying basic physicochemical consideration and biological activity assessment of nanocrystals" in Review on advanced materials science, Walter de Gruyter GmbH (2020). https://doi.org/10.1515/rams-2020-0043 М22
-
Topic Modeling of the SrpELTeC Corpus: A Comparison of NMF, LDA, and BERTopic
Modeliranje tema je efikasan način da se dobije uvid u velike količine podataka. Neki od najčešće korišćenih metoda za modeliranje tema su Latentna Dirihleova alokacija (LDA) i faktorizacija nenegativne matrice (NMF). Međutim, sa porastom modela samopažnje i unapred obučenih jezičkih modela, pojavili su se novi načini za ekstrakcju tema. BERTopic predstavlja novi pristup modeliranju tema. U ovom radu smo uporedili performanse LDA, NMF i BERTopic na književnim tekstovima na srpskom, merenjem koherentnosti tema i raznovrsnosti tema, kao i kvalitativnom ...Teodora Mihajlov, Milica Ikonić Nešić, Ranka Stanković, Olivera Kitanović. "Topic Modeling of the SrpELTeC Corpus: A Comparison of NMF, LDA, and BERTopic" in Annals of Computer Science and Information Systems, IEEE (2024). https://doi.org/10.15439/2024F1593 М33