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34 items
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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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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
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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
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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
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A necessary and sufficient condition for an algebraic integer to be a Salem number
Dragan Stankov (2019)We present a necessary and sufficient condition for a root greater than unity of a monic reciprocal polynomial of an even degree at least four, with integer coefficients, to be a Salem number. This condition requires that the minimal polynomial of some power of the algebraic integer has a linear coefficient that is relatively large. We also determine the probability that an arbitrary power of a Salem number, of certain small degrees, satisfies this condition.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. "A necessary and sufficient condition for an algebraic integer to be a Salem number" in Journal de theorie des nombres de Bordeaux (2019). https://doi.org/10.5802/jtnb.1076
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A model for estimation of stress-dependent deformation modulus of rock mass
Slavko Torbica, Veljko Lapčević (2019)Slavko Torbica, Veljko Lapčević. "A model for estimation of stress-dependent deformation modulus of rock mass" in International Journal of Mining and Geo-Engineering (2019). https://doi.org/10.22059/IJMGE.2018.255295.594729
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Correlation of uniaxial compressive strength with the dynamic elastic modulus, p –wave velocity and s –wave velocity of different rock types
Knowing mechanical properties of rocks incorporated with ultrasonic waves velocities investigations provide a secure basis for mine modelling. Uniaxial compressive strength, dynamic elastic modulus and ultrasonic waves velocities are just some of the rock properties that indicate on presence of discontinuities, stratification and fissures of rocks. Determining the relationship of these rock properties testing the rock samples that are corresponding to different rock types extracted from different mineral deposits represents the core of this study. In this paper, we ...Jelena Majstorović, Miloš Gligorić, Suzana Lutovac, Milanka Negovanović, Luka Crnogorac. "Correlation of uniaxial compressive strength with the dynamic elastic modulus, p –wave velocity and s –wave velocity of different rock types" in Underground mining engineering, Рударско - геолошки факултет - Београд (2019)
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Correlation Between Dynamic CBR and Compaction and Bearing Capacity of Pavement Foundation Layers
This paper presents a dynamic California Bearing Ratio (CBRd) device that can be used on a prepared pavement foundation layer to obtain a certain parameter of the tested material in the laboratory and in situ in a direct and fast way. For the selected natural material (gravel), it is shown that the laboratory CBRd can be used to estimate the compaction and bearing capacity, because it correlates well with the parameters of the standard and modifed Proctor compaction tests. ...korelacija parametara, donji slojevi saobraćajnica, laboratorijska i terenska ispitivanja, dinamički kalifornijski indeks nosivosti CBRd... Proctor compaction tests. Comparative tests revealed that there is good correlation between the field CBR, and the deformation modulus, and dynamic deformation modulus values obtained by field tests. Introduction The compaction and bearing capacity of natural materials are the most important ...
... The deformation modulus E,,-E,, was determined using the load-unload-load process according to the DIN 18134: 2012-04 standard [11]. Approximately 1 hour was required to prepare and perform one test. After performing SPLT and collecting the required data, the subgrade reaction modulus (K,) was calculated ...
... (stiffness), that is, the level of compaction of the material, in situ and obtains the dynamic modulus of deformation (E„) [13, 14|. In Serbia, these devices are not widespread because the dynamic modulus is not considered in the quality assessment and quality control of pavement layers. The tests ...Milan Bogdanović, Snežana Bogdanović, Dragoslav Rakić, Irena Basarić Ikodinović. "Correlation Between Dynamic CBR and Compaction and Bearing Capacity of Pavement Foundation Layers" in Soil Mechanics and Foundation Engineering, Springer Science and Business Media LLC (2024). https://doi.org/10.1007/s11204-024-09939-x
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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... experiment, was done according to the standard EN 13286-42 [19]. 2.4.3 The modulus of elasticity The modulus of elasticity represents the relationship between stress and deformation. Physical dimension of the modulus is the stress and is expressed in MPa. The experiment was done according to ...
... 47 C 6 % 209,52 L 6 % 286,90 C 6 % 161,05 3.5.3 The modulus of elasticity After 7 days of the sample storage in the wet chamber, the modulus of elasticity was tested and was in range from 58.000 to 289.000 kPa. The maximum modulus of elasticity is obtained by adding 4 % of the cement as ...
... binder the deviation results are very small, even negligible. Table 15 The modulus of elasticity after 28 days in the wet chamber Sample No. Modulus of elasticity in compression Ec / kPa Sample No. Modulus of elasticity in compression Ec / kPa 0 % 158 000 0 % 158 000 0 % 147 000 ...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
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Control of substructure construction of railways in the Republic of Serbia
Контрола збијености природног тла (у ископу) или збијеног у насипу при изградњи саобраћајница представља један од основних облика контроле квалитета доњег строја. Код изградње брзих саобраћајница (аутопутеви и брза железница) приоритет је постизање високог нивоа контроле извршених радова. У циљу онемогућавања диференцијалног слегања (при изградњи насипа), или промене запремине услед допунског збијања материјала, које неминовно доводе до деформација, потребно је извршити оптимално збијање материјала. У оквиру овог рада приказује се техничка регулатива која регулише контролу збијености при изградњи железничке ...... layer are given. Table 1 shows the required values of the dynamic modulus of deformation Evd together with the required values of the modulus of deformation Ev2. Determining the correlation coefficient between the deformation modulus Ev2 and Evd can be applied in special cases when soil 602 STEPGRAD2022 ...
... compaction and bearing capacity of the earth carcass layers is assessed by the static deformation modulus Ev2, which is determined by the test plate, while the control is performed by the dynamic deformation modulus Evd, which is determined by the light falling load experiment with base plate Ø300 mm. Technical ...
... determination of the dynamic modulus of deformation, Evd is obligatorily performed along with other tests and the stated correlation relations. Due to the fact that it is not standardized in the Regulations for main railways, tests by determining the dynamic modulus of deformation Evd are not even ...Dragan Lukić, Dragoslav Rakić, Irena Basarić Ikodinović. "Control of substructure construction of railways in the Republic of Serbia" in International Conference On Contemporary Theory and Practice in Construction XV, Banja Luka 16-17 jun 2022., University of Banja Luka Faculty of Architecture, Civil Engineering and Geodesy (2022)
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Relation between crustal stress and thickness of earth's crust
Slavko Torbica, Veljko Lapčević (2020)Slavko Torbica, Veljko Lapčević. "Relation between crustal stress and thickness of earth's crust" in Podzemni radovi (2020). https://doi.org/10.5937/podrad1935013T
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Geotechnical conditions of “Debelo brdo” tunnel construction on the highway E-80: Nis-Merdare-Pristina (“Peace Highway”)
The construction of the highway E-80 has begun in Serbia, which will represent the traffic hub of the Western Balkans and will be part of the main regional transport network of Southeast Europe. Its total length through Serbia is 77 km, and one part of the route is designed through a typical plain terrain, while a larger part of the route passes through hilly terrain. The construction of the tunnel “Debelo brdo” is planned partly in an open cut ...Dragoslav Rakić, Irena Basarić Ikodinović, Radojica Lapčević, Dragan Lukić. "Geotechnical conditions of “Debelo brdo” tunnel construction on the highway E-80: Nis-Merdare-Pristina (“Peace Highway”)" in Proceedings of the XVIII ECSMGE 2024 geotechnical engineering challenges to meet current and emerging needs of society, Lisbon, 26-30 August 2024, CRC Press (2024). https://doi.org/10.1201/9781003431749-356
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Rock slope stability analysis under Hoek–Brown failure criterion with different flow rules
The stability analysis of homogeneous rock slope following the Hoek–Brown failure criterion under the hypothesis of different flow rules is performed based on limit equilibrium and finite element methods. The applied failure criterion is the generalized Hoek–Brown that can be introduced as a shear/normal function in analysis applying different flow rules. The results are compared with those obtained by the application of equivalent shear strength parameters of the Mohr–Coulomb criterion, considering that this is still the most widely used ...Kružna klizna površ, Huk-Braunov kriterijum loma, Kriterijum popuštanja, Smičuća/normalna funkcija, Nivo napona, Verovatnoća i parametarska analizaSvetlana Melentijević, Zoran Berisavljević, Dušan Berisavljević, Claudio Olalla Marañón . "Rock slope stability analysis under Hoek–Brown failure criterion with different flow rules" in Bulletin of Engineering Geology and the Environment , Springer (2024). https://doi.org/10.1007/s10064-024-03667-0
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Uporedna analiza stabilnosti završnih kosina površinskog kopa „Veliki Krivelj“
Mihajlo Topalović (2023)Površinski kop „Veliki Krivelj“ nalazi se u blizina grada Bora i u neposrednoj blizini sela Krivelj. Od 2018. godine je u vlasništvu kineske kompanije „Zijin“ koja ima udeo od 63% vlasništva celokupnog RTB-a Bor. Na površinskom kopu obavlja se masovna eksploatacija rude bakra opremom visokog kapaciteta. Za bušenje se koriste bušilice prečnika od 250 do 310 mm, a za utovar minirane rude i jalovine bageri čija je zapremina kašike 15 m3 i 22 m3. Za površinski kop „Veliki Krivelj“ ...Mihajlo Topalović. Uporedna analiza stabilnosti završnih kosina površinskog kopa „Veliki Krivelj“, 2023
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Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit
... ongitudinal elastic waves C, = 6661.00[m/ s] , • velocity of transverse elastic waves C, = 2852.67[m/ s] ; = 62.46[GN/m2], • dynamic elasticity modulus FE„ lin • „dynamic Poisson' ratio //„„ — 0.39|iGN/m2] . 6.2 Method of blasting in the open pit Kovilovača Measurements of seismic shocks in ...
... Activating of nonel tube was performed using electric detonator. Basic data related to the number of boreholes N, the overall explosive amount Q,,, the maximal exsplosive amount by deceleration interval Q,, overali borehole depth L , and average stemming length L_ are presented in Table 1. Table 1. Review ...Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac. "Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit" in 9th International Conference Mining and Environmental protection MEP, 24 – 27 May 2023, Sokobanja, Serbia, Belgrade : University of Belgrade-Faculty of mining and geology (2023)
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Inženjerskogeološka istraživanja za potrebe izgradnje tunela T1 na putnom pravcu Požega-Kotroman
Andrija Popović (2024)Tokom izrade završnog rada korišćeni su podaci koje sam dobio u saradnji sa firmom „Saobraćajni institut CIP d.o.o.“, kao i ostala odgovarajuća stručna literatura.Osnovni cilj pisanja rada jeste definisanje određenih fizičko mehaničkih parametara i predlog podgrade i načina iskopa tunela na osnovu RMR klasifikacije.... | — Š 3 SAMPLEMARK — | Phisycalpropemies Consistepcylimits Pada o | < | Š| š| šB RR |Dectshear| - UU Water permeabiliy Oedometer compressibility modulus -slandardni | __ | KLASIFIKACIJA -4 i w š š| š 988 Š fest coefficient Š| TLA/Som Ež š iii i —| Classification Fž L Ša i H -4 ž P s|B Hi = = 55 |j ...
... STIŠLJIVOSTI / Proktorovopit| — Š _ SAMPLE MARK Phisycal properties. = ž| EO [-45-] Direct shear UU Water permeability Oedometer compressibility modulus - standardni | KLASIFIKACIJA Š š Consistency limits Particle size distibution | || ŠE Hi L e AAAO Fkv ) Ež š Š 8 i —| Classification Fi L Ša = H ...
... STIŠLJIVOSTI / Proktorovopit| — Š _ SAMPLE MARK Phisycal properties. = ž| EO [-45-] Direct shear UU Water permeability Oedometer compressibility modulus - standardni | KLASIFIKACIJA Š š Consistency limits Particle size distibution | || ŠE Hi L e AAAO Fkv ) Ež š Š 8 i —| Classification Fi L Ša = H ...Andrija Popović. Inženjerskogeološka istraživanja za potrebe izgradnje tunela T1 na putnom pravcu Požega-Kotroman, 2024
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Investigation of quantitative indicators of anisotropy based on longitudinal elastic waves propagation velocities with uncertainty
... use for creating reliable models. Further researches can be related to determine correlation between other mechanical properties such as Young’s modulus, Poisson’s ratio, bulk density and compressive strength in order to create an dynamic model of anisotropy investigation. Acknowledgement This ...Miloš Gligorić, Jelena Majstorović, Suzana Lutovac. "Investigation of quantitative indicators of anisotropy based on longitudinal elastic waves propagation velocities with uncertainty" in Underground Mining Engineering, Belgrade : University of Belgrade - Faculty of Mining and Geology (2018). https://doi.org/10.5937/PodRad1832001G
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Geotehnički aspekti izgradnje visećeg pešačkog mosta u Starom gradu u Užicu
U radu su prikazani rezultati geotehničkih istraživanja za potrebe izgradnje visećeg pešačkog mosta preko klisure reke Đetinje u Užicu. Predviđeno je da most, sistema prednapregnute trake, omogući prelaz pešacima sa desne dolinske strane na stranu Starog grada, koja je opasana strmom liticom (cca. 40 m visine). Za potrebe formiranja geotehničkog modela i strukturnog sklopa krečnjačke stenske mase korišćen je postupak fotogrametrijskog snimanja dronom. Predviđeno je da se zatežuća sila (od oko 30 MN), koju most prenosi na obalni stub, ...fotogrametrija, stabilnost kosina, pukotine, prednapregnuta sidra, test granične nosivosti, paker (Ližonov) test... potrebe izgradnje mosta na starom gradu. Rudarsko-geološki fakultet, Beograd 2 Hoek, E., Diederichs, M.S. (2006) Empirical estimation of rock mass modulus. International Journal of Rock Mechanics and Mining Sciences, 43, 203-215 ttps://doi:10.1016/j.ijrmms.2005.06.005 3 Hoek, E., Carter, T.G., ...Zoran Berisavljević, Miloš Marjanović, Uroš Đurić. "Geotehnički aspekti izgradnje visećeg pešačkog mosta u Starom gradu u Užicu" in Zbornik radova / Međunarodno naučno-stručno savetovanje Geotehnički aspekti građevinarstva i zemljotresno inženjerstvo, Vrnjačka banja, 1-3. novembar 2023., Beograd : Savez građevinskih inženjera Srbije (2023.)
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Отварање и припрема лежишта за примену коморно-стубних метода откопавања
Никола Станишић (2024)Циљ мастер рада је да кроз теоријски преглед и практични пример, прикаже процес отварања и припреме лежишта за примену коморно-стубне методе окопавања. Предмет рада је мало лежиште олово-цинкане руде, а од варијација коморно-стубних метода откопавања, изабрана је коморно-стубна метода етажног откопавања са откопавањем одoздо на доле. Рад се бави темама одабира и описа начина отварања и припреме лежишта, методама откопавања, технологијом израде просторија и откопавања лежишта, организацијом рада и проценом трошкова и економичности експлоатације.... MO)KE Ce 3aKJbyuuTH a he rpocTopuje ca npobano THII-II oru craOugimHe. Initial Element | Unit Weight Loading (MN/m3) Elastic Type Young's Modulus (MPa} Failure Criterion Material Type Tensile Strength (MPa)} Dilation Angle (deg) |riction Angle| Friction Angle. (peak) (deg) ...
... Sserength Facscr tension z > s 4 4. š unbounded shear rension Initial Element Loading Unit Weight | Elastic (MN/m3} Type Youngs Modulus (MPa) Type Tensile Strength (MPa} Dilation Angle (deg) de lr deg| es FieldStress and BodyForce 0.0267 Isotropic 6258L8 plastic 554 [ ...
... rpaHHIec JIOMa, MO)Ke Ce 3aKJbyuuTH a he npocTopuje ca npobano THII-II O craOunHe. Initial Element | Unit Weight | _Flastic (MN/m3} Type Young's Modulus (MPa) Failure Criterion Material Type Tensile' Strength (MPa) Dilation Angle \deg} |riction Angle| lpeak) (des) ||re: Fielo Stress ...Никола Станишић . Отварање и припрема лежишта за примену коморно-стубних метода откопавања, 2024
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Geofizičko reflektivno sondiranje kao test integriteta betonskog šipa
Jovo Jakišić (2024)Temelj predstavlja izuzetno bitan element svakog građevinskog objekta. Zbog toga je neophodno poštovati odgovarajuće standarde, u projektovanju i izvođenju temeljne konstrukcije.Šipovi predstavljaju jedan od načina dubokog fundiranja tj. temeljenja. Za svaki izvedeni šip pojedinačno neophodno je izvesti kontrolu kvaliteta. Postoji više postupaka kojima je mogućeizvršiti kontrolu kvaliteta, a jedan od njih je test integriteta šipa malom silom, koji je prikazan u ovom radu.Ovaj postupak se izvodi seizmometrijskom metodom, postupkom refleksije, koji je definisan međunarodnim standardom ASTM D5882.Podaci koji su prikazani ...... POVRŠ'NAŠ 0 gi08 10.00 m m/5 Slika 1. Prikaz generisanog signala (ASTM D5882) | Reference za ASTM Standard su: - C 469 Test Method for Static Modulus of Elasticity and Poisson's Ratio of Concrete in Compression - D1I98 Methods of Static Tests of Timbers in Structural Sizes - D653 Terminology ...Jovo Jakišić. Geofizičko reflektivno sondiranje kao test integriteta betonskog šipa, 2024