Претрага
323 items
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The alternative to Mahler measure of polynomials in several variables
Dragan Stankov (2024)We introduce the ratio of the number of roots of a polynomial Pd, greater than one in modulus, to its degree d as an alternative to Mahler measure. We investigate some properties of the alternative. We generalise this definition for a polynomial in several variables using Cauchy’s argument principle. If a polynomial in two variables do not vanish on the torus we prove the theorem for the alternative which is analogous to the Boyd-Lawton limit formula for Mahler measure. ...Dragan Stankov. "The alternative to Mahler measure of polynomials in several variables" in The book of abstracts XIV symposium "mathematics and applications” Belgrade, Serbia, December, 6–7, 2024 , Univerzitet u Beogradu, Matematički fakultet (2024)
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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)
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An alternative to Mahler Measure of polynomials
Dragan Stankov (2024)We introduce the ratio of the number of roots of a polynomial Pd, greater than one in modulus, to its degree d as an alternative to Mahler measure. We investigate some properties of the limit ratio. We generalise this definition for a two variable polynomial P(x,y) using the Cauchy’s argument principle. We present an algorithm for calculating the limit ratio and a numerical method for its approximation. We estimated the limit ratio for some families of polynomials. Some examples ...Dragan Stankov. "An alternative to Mahler Measure of polynomials" in The book of abstracts XV serbian mathematical congress, Belgrade, Serbia, june, 19–22, 2024, Univerzitet u Beogradu, Matematički fakultet (2024)
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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 polynomials... plusieurs variables. Certains exemples suggèrent une conjecture pour les polynômes à deux variables qui est analogue à la formule limite de Boyd pour la mesure de Mahler. Funding. Partially supported by Serbian Ministry of Education and Science, Project 174032. Manuscript received 5th December 2019, ...
... Boyd’s limit formula for Mahler measure. Résumé. Nous introduisons une suite P2n de polynômes unitaires réciproques avec des coefficients entiers ayant les coefficients centraux fixes. Nous prouvons que le rapport entre le nombre de racines non unimo- dulaires de P2n et son degré d a une limite lorsque ...
... . This example as well as numerical approximations of LC of many other polynomials in two variables using the formula (2) and the definition (4) suggest us that the Boyd’s limit formula in Theorem 5 is also valid for LC i.e. we propose the following Theorem 6. As m →∞, LC (W (x, xm)) → LC (W (x, ...Dragan Stankov. "The number of unimodular roots of some reciprocal polynomials" in Cmptes rendus mathematique (2020). https://doi.org/10.5802/crmath.28
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Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia
Bojan Kostić, Pavle Tančić, Natalija Batoćanin. "Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia" in Geological Quarterly, septembar 2024, Polish Geological Institute - National Research Institute (PGI-NRI) (2024). https://doi.org/10.7306/gq.1752
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Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia
Bojan Kostić, Pavle Tančić, Natalija Batočanin. "Trace elements and garnet formation in a distal skarn zone: a case study of the Rudnik deposit, Central Serbia" in Geological Quarterly, Polish Geological Institute - National Research Institute (PGI-NRI) (2024). https://doi.org/10.7306/gq.1752
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Quantitative analysis of syllable properties in Croatian, Serbian, Russian, and Ukrainian
Biljana Rujević, Marija Kaplar, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Jan Mačutek (2021)... (2009: 3) suggest 10,000 words as the upper limit of a U n co rr ec te d p ro o fs - J o h n B en ja m in s P u b li sh in g C o m p an y Quantitative analysis of syllable properties 63 homogeneous text. Admittedly, it is an ad hoc limit, but long texts are necessarily mixtures ...
... First, a novel is usually considered to be too long to constitute a homoge- neous text. Popescu et al. (2009: 3) suggest 10,000 words as the upper limit of a 62 Biljana Rujevic et al. 3.4 Menzerath-Altmann law While the results on syllable frequency, syllable length, and their mutual relation could ...
... 4 2.17 2.16 2.33 2.31 5 2.11 2.09 2.27 2.22 6 2.08 2.07 2.25 2.22 7 2.08 2.11 2.21 2.27 8 2.20 homogeneous text. Admittedly, it is an ad hoc limit, but long texts are necessarily mixtures (of particular chapters, of replicas in dialogues, etc.). Second, the possi- bility that function (1) is not ...Biljana Rujević, Marija Kaplar, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Jan Mačutek. "Quantitative analysis of syllable properties in Croatian, Serbian, Russian, and Ukrainian" in Language and Text: Data, models, information and applications, John Benjamins Publishing Company (2021). https://doi.org/10.1075/cilt.356.04ruj
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Arsenic in Tap Water of Serbia´s South Pannonian Basin and Arsenic Risk Assessment
Petar Papić, Marina Ćuk, Maja Todorović, Jana Stojković, Bojan Hajdin, Nebojša Atanacković, Dušan Polomčić (2012)Petar Papić, Marina Ćuk, Maja Todorović, Jana Stojković, Bojan Hajdin, Nebojša Atanacković, Dušan Polomčić. "Arsenic in Tap Water of Serbia´s South Pannonian Basin and Arsenic Risk Assessment" in Polish Journal of Environmental Studies (2012)
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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
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Slope Stability Analyses Using Limit Equilibrium And Soil Strength Reduction Methods
Berisavlјević Zoran, Berisavlјević Dušan, Čebašek Vladimir, Rakić Dragoslav. "Slope Stability Analyses Using Limit Equilibrium And Soil Strength Reduction Methods" in Građevinar 67 no. 10, Zagreb:HSGI - Croatian Association of Civil Engineers (2015): 975-983
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Sinteza i strukturna karakterizacija nanoprahova opšte formule Ca1-xRExMnO3 (RE=Y| La)
Jelena Zagorac (2011)Jelena Zagorac. Sinteza i strukturna karakterizacija nanoprahova opšte formule Ca1-xRExMnO3 (RE=Y| La), Beograd:Rudarsko-geološki fakultet, 2011
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Soil oscillation law parameter determination with the application of Lagrange’s theorem at “Kovilovača“ open pit
Suzana Lutovac, Nebojša Vidanović, Čedomir Beljić, Zoran Gligorić. "Soil oscillation law parameter determination with the application of Lagrange’s theorem at “Kovilovača“ open pit" in Mining and Metallurgy Engineering Bor, Bor : Mining and Metallurgy Institute Bor (2015). https://doi.org/10.5937/MMEB1503053L
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Arsenic in tape waters of the south Pannonian basin (Serbia) and arsenic risk assessment
Petar Papić, Marina Ćuk, Maja Todorović, Jana Stojković, Bojan Hajdin, Nebojša Atanacković, Dušan Polomčić (2012)Petar Papić, Marina Ćuk, Maja Todorović, Jana Stojković, Bojan Hajdin, Nebojša Atanacković, Dušan Polomčić. "Arsenic in tape waters of the south Pannonian basin (Serbia) and arsenic risk assessment" in Polish Journal of Enivronmental Studies 21 no. 6, Olsztyn, Poland : Polish Journal of Enivronmental Studies (2012): 1783-1790
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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
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Sinteza i karakterizacija nanoprahova u CeO2-Bi2O3 sistemu
Marija D. Prekajski (2014-04-04)Nanoprahovi kristalnih faza iz serije čvrstih rastvora u pseudo-binarnom sistemuCeO2-Bi2O3 sintetisani su primenom jednostavne i ekonomične samopropagirajućemetode na sobnoj temperaturi korišćenjem nitrata metala i natrijum-hidroksida kaopolaznih supstanci. Osim krajnjih članova niza, CeO2 i niskotemperaturne polimorfnemodifikacije α-Bi2O3, sintetisani su i čvrsti rastvori nominalnog sastava Ce1-xBixO2-δ,gde je x = 0,1; 0,2; 0,3; 0,4; 0,5; 0,6; 0,7; 0,8; 0,9. Rezultati proučavanja metodomrendgenske difraktometrije na polikristalnom materijalu i ramanske spektroskopskeanalize pokazali su da su sintetisani prahovi sa nižim sadržajem bizmuta (x = 0,1 ...nanostrukturni materijali, čvrsti rastvori, CeO2, Bi2O3, rendgenskadifraktometrija praha, Ritveldova metoda, mikrostrukrurna analizaMarija D. Prekajski. "Sinteza i karakterizacija nanoprahova u CeO2-Bi2O3 sistemu" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2014-04-04)
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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
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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
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Analiza osnovnih indikatora upotrebnog kvaliteta mašina pomoćne mehanizacije na površinskim kopovima uglja
Stevan Đenadić, Dragan Ignjatović, Predrag Jovančić, Milena Lekić, Žarko Aleksić, Ivan Janković (2022)Izbor optimalnog tipa mašine i adekvatno upravljanje kroz životni vek je kompleksan zadatak. Osnovna pitanja koje se postavljaju prilikom rešavanja ovog zadatka vezana su za stepen zadovoljenja rada mašine i optimalan trenutak zamene iste. U ovom radu je izvršena analiza rada dozera koji su u radu na površinskom kopu lignita RB Kolubara. Analizom je obuhvaćeno 4 različita proizvođača dozera a to su: Caterpillar, Dressta i Shantui i Liebherr. Analiza je izvršena sa aspekta ukupnih troškova koji se stvaraju i ...Stevan Đenadić, Dragan Ignjatović, Predrag Jovančić, Milena Lekić, Žarko Aleksić, Ivan Janković . "Analiza osnovnih indikatora upotrebnog kvaliteta mašina pomoćne mehanizacije na površinskim kopovima uglja" in XV međunarodna konferencija o površinskoj eksploataciji OMC 2022, 12-15. oktobar, Zlatibor, Jugoslovenski komitet za površinsku eksploataciju (2022)
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Analiza nosivosti vertikalno opterećenog šipa za potrebe izgradnje petlje „Merošina 1“ na autoputu E-80 deonica: Niš – Merošina
U Srbiji je počela izgradnja autoputa E-80 koji će predstavljati saobraćajno čvorište zapadnog Balkana i biće deo glavne regionalne transportne mreže jugoistočne Evrope. Njegova ukupna dužina kroz Srbiju iznosi 77 km, a prva deonica u dužini od 5.5 km je završena i puštena u saobraćaj krajem jula 2023. god. To je prva od četiri deonice Sektora 1 čija je dužina 32.65 km. U sklopu petlje „Merošina 1“ izgrađen je nadvožnjak koji je oslonjen na devet stubnih mesta na međusobnom ...Dragoslav Rakić, Nikola Božović, Miloš Stevanović, Milan Bogdanović. "Analiza nosivosti vertikalno opterećenog šipa za potrebe izgradnje petlje „Merošina 1“ na autoputu E-80 deonica: Niš – Merošina" in Geotehnički aspekti građevinarstva i zemljotresno inženjerstvo – Vrnjačka Banja, 01-03. novembar 2023., Beograd : Savez građevinskih inženjere Srbije (2023)
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Analiza parametara bušenja i miniranja na površinskom kopu „Čokoće“ - Novi Popovacu softverskom paketu O-Pitblast
Aleksandar Đorđević (2024)Bušenje i miniranje predstavlja prvu fazu u otkopavanju čvrstih mineralnih sirovina, kako u podzemnoj tako i u površinskoj eksploataciji.Bušenjem i miniranjem vrši se njihovo odvajanje iz masiva i drobljenje na komade neophodne krupnoće.Uprkos razvijenoj mehanizaciji, praktično jedini efikasni postupak otkopavanja čvrstih stenskih masiva zasnovan je na primeni eksploziva.Ležište krečnjaka “Čokoće” kao i cementara “Moravacem” nalaze se u Popovcu kod Paraćina u centralnom delu Srbije. Preduzeće datira još iz davne 1928.godine, koje je tada, u improvizovanim pećima, peklo i proizvodilo kreč.Od 2015. ...... vrednosti kopa. Razmatraće se dva slučaja: > slučaj optimalne konture kopa na celom ležištu bez ograničenja u smislu kategorizacije rezervi, tjJ. bez limita granicom rezervi A+B+C1, > optimalna kontura kopa unutar granice C1 rezervi. Konačna moguća kontura kopa krečnjaka Čokoće, određena je ekonomskom ...
... eksploatacione rezerve iznose 86 720 151 t za vek kopa od oko 110 godina, sa godišnjim kapacitetom između 800 000 i 900 000 tona. 19 Uvođenjem limita – granica C1, smanjenje su ukupne rezerve za oko 35% tako da eksploatacione rezerve završne konture kopa iznose oko 56 miliona tona. Slika 3.8 ...
... širina etažne radne etaže Kod rada bagera u otkopu po tehnološkoj šemi datoj na slici 3.5 minimalna širina etažne ravni radne etaže računa se po formuli : Se=e+Z+Ž+Ri+Rk—tg_a (m) gde je: e — širina zaštitne berme, (2 m) z — sigurnosno rastojanje od berme, (1 m) B – širina kamiona Ri – minimalni ...Aleksandar Đorđević. Analiza parametara bušenja i miniranja na površinskom kopu „Čokoće“ - Novi Popovacu softverskom paketu O-Pitblast, 2024