Претрага
218 items
-
On the distribution modulo 1 of the sum of powers of a Salem number
Dragan Stankov (2016)It is well known that the sequence of powers of a Salem number θ, modulo 1, is dense in the unit interval, but is not uniformly distributed. Generalizing a result of Dupain, we determine, explicitly, the repartition function of the sequence , where P is a polynomial with integer coefficients and θ is quartic. Also, we consider some examples to illustrate the method of determination.Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomialsDragan Stankov. "On the distribution modulo 1 of the sum of powers of a Salem number" in Comptes rendus Mathematique (2016). https://doi.org/10.1016/j.crma.2016.03.012 М23
-
Definition of criteria and alternatives for choosing the optimal mining method deposits when applying multi: Criteria optimization, Belgrade, June 2024
Sanja Bajić, Dragoljub Bajić, Branko Gluščević, Radmila Gaćina, Josip Išek. "Definition of criteria and alternatives for choosing the optimal mining method deposits when applying multi: Criteria optimization, Belgrade, June 2024" in Podzemni radovi, Beograd, jun 2024, Centre for Evaluation in Education and Science (CEON/CEES) (2024). https://doi.org/10.5937/podrad2444071B М51
-
Imputing missing data using grey system theory and the biplot method to forecast groundwater levels and yields
Groundwater management is one of today’s important tasks. It has become necessary to seek out increasingly reliable methods to conserve groundwater resources. Dependable forecasting of the amounts of groundwater that can be abstracted in a sustainable manner requires longterm monitoring of the groundwater regime (rate of abstraction and groundwater levels). Monitoring of the groundwater source for the town of Bečej, Serbia had been disrupted for multiple years. The objective of the paper is to assess the possibility of reinterpreting ...Jelena Ratković, Dušan Polomčić, Zoran Gligorić, Dragoljub Bajić. "Imputing missing data using grey system theory and the biplot method to forecast groundwater levels and yields" in Geologia Croatica, Hrvatski geološki institut (2022). https://doi.org/10.4154/gc.2022.14 М23
-
Estimating hydraulic parameters for the complex hydrodynamic models
Hydrodynamic models have usually been calibrated manually, by trial-and-error, with different values of hydraulic parameters and hydraulic characteristics of boundary conditions. This method of calibration and estimation of hydraulic parameters requires an extensive knowledge and experience of experts, but whether the resulting solution includes an optimal set of parameters still remains an open question. An optimization method founded upon the Gauss-Marquardt-Levenberg algorithm, along with PEST software based on that algorithm, introduces automation of model calibration with regularization, which substantially ...Dušan Polomčić, Dragoljub Bajić, Jelena Ratković, Bojan Hajdin. "Estimating hydraulic parameters for the complex hydrodynamic models" in Mining and Metallurgy Engineering Bor, Centre for Evaluation in Education and Science (CEON/CEES) (2018). https://doi.org/10.5937/mmeb1704029P М24
-
The Reciprocal Algebraic Integers Having Small House
Dragan Stankov (2021)Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomialsDragan Stankov. "The Reciprocal Algebraic Integers Having Small House" in Experimental Mathematics (2021). https://doi.org/ 10.1080/10586458.2021.1982425 М22
-
Exploring the flipped model in the CLIL geology classroom
Lidija Beko, Marija Đorđević (2024)Lidija Beko, Marija Đorđević . "Exploring the flipped model in the CLIL geology classroom" in Inovacije u nastavi, Centre for Evaluation in Education and Science (CEON/CEES) (2024). https://doi.org/10.5937/inovacije2403090B М23
-
Density maps from gravity inversion as a tool for the basin basement analysis and imaging
Ivana Vasiljević (2023)Previously devised method for density mapping of the Cenozoic basin’s basement is further developed in order to improve the visualization and geological interpretation of the results. The method combines gravity-density inversion with forward modeling and requires gravity anomaly and depth-to-basement data. Although it was primarily designed for application in well-researched basins, such as Pannonian basin, method does not require further constrains. An information on density distribution in the Cenozoic sediments (from density logging or core density measurements) is important ...Ivana Vasiljević. "Density maps from gravity inversion as a tool for the basin basement analysis and imaging" in GEOSCIENCE 2023, Bucharest, Romania, November 9-11, 2023., Bucharest : SGAR - Romanian Society of Applied Geophysics (2023) М32
-
Method validation and geochemical modelling of chromium speciation in natural waters
The study focuses on validating reference methods such as ICP-OES and ICP-MS for detecting ultratrace levels of chromium in groundwater, where concentrations are typically very low. Additionally, it verifies a hyphenated technique, IC-ICP-MS, for determining naturally occurring Cr(VI) in tested waters. The validation process involved various chromium analysis variants, including isotopes 52Cr and 53Cr in ICP-MS and IC-ICP-MS techniques, along with specific emission lines in the ICPOES technique. Statistical data processing revealed that the achieved limits of quantification for ...шестовалентни хром, ИЦ-ИЦП-МС, технике са цртицама, геохемијско моделирање, анализа спецификација, валидација методеPiotr Rusiniak, Katarzyna Wątor, Ewa Kmiecik, Vesna Ristić Vakanjac. "Method validation and geochemical modelling of chromium speciation in natural waters" in Scientific Reports, Springer Science and Business Media LLC (2024). https://doi.org/10.1038/s41598-024-77425-3 М21
-
A WordNet Ontology in Improving Searches of Digital Dialect Dictionary
In this paper, we present a method for automatic generation of a digital resource, which connects all indirect synonyms of a dialect term to all indirect synonyms of a corresponding term in the standard language, aiming to improve the search of a digital dialect dictionary. The method uses SWRL rules defined in the Serbian WordNet ontology to identify sets of synonymous words. It also uses e-dictionaries to produce correct lemmas in standard language that users usually employ in searches. ...Miljana Mladenović, Ranka Stanković, Cvetana Krstev. "A WordNet Ontology in Improving Searches of Digital Dialect Dictionary" in New Trends in Databases and Information Systems: ADBIS 2017 Short Papers and Workshops - SW4CH (Semantic Web for Cultural Heritage) 767, Springer International Publishing (2017). https://doi.org/10.1007/978-3-319-67162-8_37 M33
-
The number of unimodular roots of some reciprocal polynomials
Dragan Stankov (2020)We introduce a sequence P2n of monic reciprocal polynomials with integer coefficients having the central coefficients fixed. We prove that the ratio between number of nonunimodular roots of P2n and its degree d has a limit when d tends to infinity. We present an algorithm for calculation the limit and a numerical method for its approximation. If P2n is the sum of a fixed number of monomials we determine the central coefficients such that the ratio has the minimal limit. ...Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomialsDragan Stankov. "The number of unimodular roots of some reciprocal polynomials" in Cmptes rendus mathematique (2020). https://doi.org/10.5802/crmath.28 М23
-
Underground loading-haulage equipment selection with application of topsis method with different weighting methods of criteria
The choice of adequate mining machines is one of the most complex problems in the underground exploitation of mineral raw materials. The weight of such a decision is reflected in the high prices of these machines and the occurrence of even greater costs during their use if their choice was wrongly conceived. There are numerous examples from practice in which such decisions were made solely on the basis of comparing the prices of machines, without considering any of the ...utovarno-transportna mehanizacija, izbor, TOPSIS, entropija, standardna devijacija, težina kriterijumaVladimir Krivošić, Luka Crnogorac, Rade Tokalić. "Underground loading-haulage equipment selection with application of topsis method with different weighting methods of criteria" in Underground mining engineering, University of Belgrade - Faculty of Mining and Geology (2024) М51
-
Research on influence of track stiffness on development of rail squat defects
This paper presents research aiming to establish the relationship between track stiffness and the appearance and development of squat defects on running rails. Uneven incidence of squat defects was observed on the rails of the investigated main transit track in arailway station. Inspection of track support conditions was conducted using an electrometric method. The comparative analysis of the research results indicated a correlation between the incidence of squats and the changes in track support stiffness. The electrometric profiles and ...Milica Mićić, Zdenka Popović, Luka Lazarević, Dejan Vučković, Ljiljana Brajović. "Research on influence of track stiffness on development of rail squat defects" in Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, SAGE Publications (2024). https://doi.org/10.1177/09544097241306463 М23
-
Prirodna ranjivost karstnih izdani srednjetrijaskih krečnjaka u oblasti između reka Bistrice, Uvca i Lima
Branislav Petrović, Veljko Marinović, Zoran Stevanović. "Prirodna ranjivost karstnih izdani srednjetrijaskih krečnjaka u oblasti između reka Bistrice, Uvca i Lima" in 18. Kongres geologa Srbije, Srpsko geološko društvo (2022) М64
-
Testing the energy value of different types of coal by the method of active thermography
In this paper, coal thermograms are presented and analyzed in order to determine their energy value. Two types of coal of different categories, brown and lignite, were selected for active thermographic imaging. The tested coal samples were processed before measurement so that they are similar in dimensions and have two plane-parallel smooth surfaces. The test samples were "primarily" heated under the same conditions and the process of their cooling was monitored by a thermal camera. "Then" they were cooled ...Stevan Đenadić, Ljubiša Tomić, Vesna Damnjanović, Predrag Jovančić, Dragutin Jovković. "Testing the energy value of different types of coal by the method of active thermography" in 9th International Scientific Conference on Defensive Technologies, Belgrade, Serbia, 15-16 October 2020, The Military Technical Institute (2020) М33
-
The number of nonunimodular roots of a reciprocal polynomial
Dragan Stankov (2023)We introduce a sequence Pd of monic reciprocal polynomials with integer coefficients having the central coefficients fixed as well as the peripheral coefficients. We prove that the ratio of the number of nonunimodular roots of Pd to its degree d has a limit L when d tends to infinity. We show that if the coefficients of a polynomial can be arbitrarily large in modulus then L can be arbitrarily close to 0. It seems reasonable to believe that if ...Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomialsDragan Stankov. "The number of nonunimodular roots of a reciprocal polynomial" in Comptes rendus mathematique, Elsevier France Editions Scientifiques et Medicales (2023). https://doi.org/10.5802/crmath.422 М23
-
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 М22
-
Ocena zaštitne funkcije povlatnih slojeva izvorišta Jasik (Opština Batočina) primenom GLA metode
U cilju utvrđivanja rezervi podzemnih voda i analize uslova zaštite u periodu 2012. i 2013. godine, sprovedena su detaljna hidrogeološka istraživanja na području izvorišta Jasik (opština Batočina). Uspostavljen je sistem monitoringa, čiji je rezultat predstavljao prikupljanje detaljnih hidrogeoloških podataka. Za potrebe analize, izrađen je hidrodinamički model, na osnovu koga je simulirano kretanje podzemnih voda, odnosno, utvrđene zone sanitarne zaštite. Pored navedenog, za potrebe utvrđivanja uslova zaštite podzemnih voda, bilo je neophodno utvrditi podložnost aluvijalne izdani izvorišta Jasik zagađenju. Polazeći ...Rastko Petrović, Igor Jemcov, Dušan Polomčić. "Ocena zaštitne funkcije povlatnih slojeva izvorišta Jasik (Opština Batočina) primenom GLA metode" in Vodoprivreda, Srpsko društvo za navodnjavanje i odvodnjavanje (2014) М52
-
2D geoelectrical resistivity tomography application at the former city waste dump "Ada Huja": Eco-geological problem
Branislav Sretenović, Filip Arnaut, Ivana Vasiljević, Vesna Cvetkov. "2D geoelectrical resistivity tomography application at the former city waste dump "Ada Huja": Eco-geological problem" in Podzemni radovi, Centre for Evaluation in Education and Science (CEON/CEES) (2019). https://doi.org/10.5937/PodRad1934059S М51
-
Multiple-Criteria Decision-Making in Mine Development Planning
Sanja Bajić (2023)The Borska Reka ore deposit is an experimental location where developed methodologies have been applied. It is the largest ore body within the Bor mining complex, which has been the subject of numerous studies and analyses for more than three decades. The paper focuses on the application of FAHP and the VIKOR method to address ranking of alternatives and select the optimal mining method by means of fuzzy multicriteria optimization.Sanja Bajić. "Multiple-Criteria Decision-Making in Mine Development Planning" in Proceedings of the 5th International Underground Excavations Symposium, 5-6-7 June 2023, Istanbul, Topkapi : Dinç Ofset Mat. Rek. San. ve Tic. Ltd. Şti. (2023) М33
-
Vulnerability methods in hard rock formation as a basis for groundwater risk assessment – from resource to source
Groundwater in a hard rock formation is most endangered at places where a potential source can discharge contaminants that can reach the saturated zone of an aquifer. In these circumstances, an essential tool for groundwater protection is the contamination risk map. This map is based on the integration of two maps: a hazards map, i.e., map of potential sources of contamination and a vulnerability map. The selection of a proper vulnerability method is an important task since the resulting ...karta rizika od kontaminacije, ranjivosti podzemnih voda, DRASTIC, EPIK, PI, COP, Nacionalni park TaraVladimir Živanović, Igor Jemcov, Veselin Dragišić. "Vulnerability methods in hard rock formation as a basis for groundwater risk assessment – from resource to source" in Geologia Croatica, Croatian Geological Survey (2022). https://doi.org/10.4154/gc.2022.23 М23