Претрага
503 items
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Синтеза и карактеризација керамике на бази сфена
Jelena R. Pantić (2015-07-10)Механохемијска активација стехиометријске смеше реактаната TiO2, SiO2 и CaCO3 показала се као веома успешна и једноставна метода за добијање сфена (CaTiSiO5). На основу мерења релативних густина свих синтерованих узорака установљено је да максималну густину од 93,9 % имају узорци који су активирани 30 минута и синтеровани на 1200 °С. Микроструктурном анализом, тј. анализом слика синтерованих узорака активираних 30 минута, које су добијене скенирајућом електронском микроскопијом, опажа се бимодална расподела величине зрна, са просечном величином од 3 μm, односно 5 ...сфен, механохемија, Ритвелдова метода, оптичка спектроскопија, микроструктурна анализа, фазна трансфоpмација, чврсти раствори... осциловања решетке и локалног загревања на контактним местима, хемијских реакција, декомпозиције, измене јона, оксидо-редукције, формирања комплекса захваљујући физичким променама које се одигравају у току процеса итд. Од посебног значаја су секундарни ефекти који подразумевају интеракцију ...
... материјала, облика примарних кристалита и честица, јачине међучестичних веза, а у највећој мери од расподеле величине честица, мада нису занемарљиви ни други утицаји као што су количина и врста везива, влажност атмосфере и температура (Messing et al., 1982; German, 1989). Током пресовања, услед ...
... дисторзије TiO6 октаедра услед Јан-Телеровог електронског ефекта другог реда. TiО6 октаедри се не могу описати као правилни, јер шест Ti-О растојања нису ни приближно једнака. Октаедри су искривљени и ширење није подједнако у сва три правца, већ је померено у правцу а-осе. Вредности Ti-О веза варирају у ...Jelena R. Pantić. "Синтеза и карактеризација керамике на бази сфена" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2015-07-10)
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Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine
Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović (2019)Availability is one of the most used terms in maintainability engineering. This concept is used to denote: The quality of service of an engineering system, i.e., machines, weak points’ analysis, asset management, as well as making decisions in the process of life cycle management. Availability is an overall indicator and contains partial indicators that are oriented towards reliability, maintenance, and logistical support. Availability presents a variable value and changes in time and space. Usually, availability is shown as the ...... = 1 to n: Ri = (µR(1), . . . ,µR( j), . . . ,µR(n)); Mi = (µM(1), . . . ,µM( j), . . . ,µM(n)); Si = (µS(1), . . . ,µS( j), . . . ,µS(n)). (9) (ii) The membership functions can form C= n3 combinations among themselves. Each combination Ac represents practically one possible assessment Ai(8). Ac ...
... membership function p and class j = 1 to n: R; = (UR(1), ++ UR(j)s +++ LR(n))i Mi = (Ha(ays «++ MMi) +7 Haan) ” Si = (Us(ajy «+7 Hs(j)r «+7 H8(n))- y (ii) The membership functions can form C = n° combinations among themselves. Each combination Ac represents practically one possible assessment Aj(8). Ac ...
... according to the algorithm, Section 2.2.1: (i) Input data are of fuzzy relationship: {urg7-N, UmB1-N, and [sp1-n (9). Energies 2019, 12, 4044 13 of 18 (ii) In this case, it is possible to form: C = 103 = 1000 combinations. The combinations carry the code mark in the general record: jR-jM-jS, for j = 1 ...Stevan Đenadić, Dragan Ignjatović, Miloš Tanasijević, Uglješa Bugarić, Ivan Janković, Tomislav Šubaranović. "Development of the Availability Concept by Using Fuzzy Theory with AHP Correction, a Case Study: Bulldozers in the Open-Pit Lignite Mine" in Energies, MDPI AG (2019). https://doi.org/10.3390/en12214044
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Efekti potencijalnog korišćenja postrojenja za preradu otpadnih voda kao energetskih izvora u sistemima daljinskog grejanja u Srbiji
Системи даљинског грејања постоје у 57 градова и општина у Србији и доминантно користе фосилна горива. У овим урбаним срединама су изграђени, или се планира градња система за пречишћавање отпадних вода. У раду је размотрена (са еколошког и енергетског аспекта) могућност додатног, енергетског коришћења топлоте пречишћене воде у СДГ, применом топлотних пумпи. На примеру Шапца је извршено поређење постојећег СДГ са системом који би применом топлотних пумпи искористио енергетски потенцијал система за пречишћавање отпадних вода. Добијени индикатори су послужили ...... пумпе у систем даљинског грејања. Кључне карактеристике СПОВ-а за избор топлотне пумпе су проток од 159,67 kg/s и температура пречишћене воде која се ни у зимским месецима не спушта испод 11°C. Подаци из Шапца су послужили за анализу могућих ефеката интеграције топлотних пумпи и у друге системе даљинског ...Dejan Ivezić, Marija Živković, Aleksandar Madžarević . "Efekti potencijalnog korišćenja postrojenja za preradu otpadnih voda kao energetskih izvora u sistemima daljinskog grejanja u Srbiji" in Stručno-naučna konferencija TOPS 2019, Poslovno udruženje toplana Srbije (2019)
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Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry
Self-engineering is a relatively new branch of knowledge that aims to understand how systems could “autonomously” re-configure or repair themselves without the intervention of the operators. A direct field of application is within the maintenance spectrum. Having systems or machines capable of self-detecting or even self-repairing could represent a game-changer, in capital asset fields such as the mining industry in particular. This paper aims to investigate the possible benefits and challenges of self-engineering / self-maintenance concerning mining machines, specifically bucket-wheel ...self-engineering, self-maintenance, maintenance operations, mining industry, bucket-wheel excavator, gearbox revitalizationSteven Manders, Milorad Pantelić, Vladimir Milisavljević, Alberto Martinetti. "Self-Engineering: Possibilities for Maintenance Operations in the Mining Machines Industry" in SSRN Electronic Journal, Elsevier BV (2021). https://doi.org/10.2139/ssrn.3945979
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Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit
... can be written in the form: — %* — · R whereby integration, it is obtained: v Av AR — ~-n·| —,,respectively: logv=logR" +logC; j v j R p y: 108 ii Š (6) where C is a constant of integration. Equation (6) can be written in the form: logv=logC·R"; () 4. MODELS FOR DETERMINING PARAMETERS FOR ...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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Upotreba lidar tehnologije i digitalne fotogrametrije primenom iPhone pametnih telefona na primeru rudnika "Rudnik"
Nikola Mirković, Luka Crnogorac, Aleksa Paunović. "Upotreba lidar tehnologije i digitalne fotogrametrije primenom iPhone pametnih telefona na primeru rudnika "Rudnik"" in 15. Simpozijum „Rudarstvo 2024“ Održivi razvoj u rudarstvu i energetici, Vrnjačka banja, 21-24. maj 2024., Beograd : Institut za tehnologiju nuklearnih i drugih mineralnih sirovina (2024)
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Analiza uporednog praćenja temperature površine ohlađenih materijala pri njihovom zagrevanju do ambijentalne temperature
U datom eksperimentalnom radu su termografskim metodama ispitivane termofizičke karakteristike različitih materijala. Za ispitivanja su izabrani mesingani niovčić, ugalj i pelet, jer imaju različita termoizolaciona svojstava i različito stanje površine. Uzorci su najpre hlađeni, a zatim je njihovo zagrevanje na sobnoj temperaturi praćeno termalnom kamerom. U drugom delu eksperimenta, korišćena je impulsna termografija, a zagrevanje površine uzoraka vršeno je svetlosnom pobudom.Stevan Đenadić, Ljubiša Tomić, Vesna Damnjanović, Katarina Nestorović. "Analiza uporednog praćenja temperature površine ohlađenih materijala pri njihovom zagrevanju do ambijentalne temperature" in 65. godišnja konferencija za elektroniku, telekomunikacije, računarstvo, automatiku i nuklearnu tehniku ETRAN 2021, Etno selo Stanišići, Republika Srpska, 8-10. septembar 2021., Društvo za ETRAN Beograd i Akademska misao Beograd (2021)
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Split-Desktop software for the analysis of fragment size distribution of blasted rock mass
Milanka Negovanović, Lazar Kričak, Stefan Milanović, Jovan Marković, Nikola Simić, Snežana Ignjatović (2023)Drobljenje stena je najvažniji pokazatelj u proceni efekata miniranja pri proizvodnom miniranju u površinskoj eksploataciji. Stepen drobljenja stena ima veliki uticaj na efikasnost daljih operacija utovara, transporta, drobljenja i mlevenja. Optimalno drobljenje stena pri proizvodnom miniranju utiče na smanjenje ukupnih troškova proizvodnje. Stoga je pouzdana procena veličine drobljenja odminirane stenske mase veoma važno pitanje, ne samo u operacijama miniranja, već i u rudarskoj proizvodnji. Za predviđanje distribucije veličine komada odminirane stenske mase postoje različiti empirijski modeli. KUZ-RAM model omogućava ...Milanka Negovanović, Lazar Kričak, Stefan Milanović, Jovan Marković, Nikola Simić, Snežana Ignjatović. "Split-Desktop software for the analysis of fragment size distribution of blasted rock mass" in 9th International Conference Mining and environmental protection, Sokobanja, Serbia, 24 – 27. May 2023, Belgrade : University of Belgrade, Faculty of Mining and Geology (2023)
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Low-temperature phase transition and magnetic properties of K3YbSi2O7
Predrag Dabić, Volker Kahlenberg, Biljana Krüger, Marko Rodić, Sabina Kovač, Jovan Blanuša, Zvonko Jagličić, Ljiljana Karanović, Václav Petříček, Aleksandar Kremenović (2021)alkalni silikati elemenata retkih zemalja, fazni prelazi, magnetne karakteristike, razdvajanje kristalnog polja, silikati lantanica... �3 K2—O2 3.3067 (3) �3 Si1—O2 1.6411 (17) O1—Si1—O1iii 110.65 (11) �3 Si1iv—O2—Si1 180.0 O1—Si1—O2 108.27 (11) �3 Symmetry code: (i) x � y, x, �z; (ii) �y, x � y, z; (iii) �x + y + 1, �x + 1, z; (iv) x, y, �z + 1 2. Table 4 Bond valence sums ij (v.u.) for the cations and anions in �-polymorph. K1a ...
... vi 111.0 (3) O2—Si1—O3 105.3 (4) O1v—Si1—O2 110.8 (2) �2 Si1—O3—Si1vii 164.3 (7) O1v—Si1—O3 109.4 (2) �2 Symmetry codes: (i) x + 1 2, y + 1 2, z; (ii) x, �y, �z + 1; (iii) �x, �y, z � 1 2; (iv) � x � 1 2, � y � 1 2, z � 1 2; (v) x � 1 2, �y � 1 2, �z + 1; (vi) �x + 1 2, �y � 1 2, �z + 1; (vii) ...
... —O2—-Sil 180.0 K2—O1 2.742 (4) x4 Yb1—O1 2.212 (4) x4 O1—Sil—O2 108.27 (11) x3 K2—02"% 2.827 (7) x2 Yb1—O2 2.222 (6) x2 Symmetry code: (i) x — y, x, —z; (ii) —y, x — y, z (iii) -x + y +1, —x +1, z O1’—Sil—O1" 111.0 (3) 02—Sil—O3 105.3 (4) (iv) x,y, —z +3. O1’—Sil—O2 110.8 (2) x2 Sil—O3—Sil 164.3 (7) O1’—Sil—O3 ...Predrag Dabić, Volker Kahlenberg, Biljana Krüger, Marko Rodić, Sabina Kovač, Jovan Blanuša, Zvonko Jagličić, Ljiljana Karanović, Václav Petříček, Aleksandar Kremenović. "Low-temperature phase transition and magnetic properties of K3YbSi2O7" in Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials, International Union of Crystallography (IUCr) (2021). https://doi.org/10.1107/S2052520621006077
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Composition of organic matter and thermal maturity of Mesozoic and Cenozoic sedimentary rocks in East Herzegovina (External Dinarides, Bosnia and Herzegovina)
This paper presents the first data on the organic matter and thermal maturity of Mesozoic and Cenozoic sedimentary rocks in the East Herzegovina region of the External Dinarides. Representative, organic-rich samples from outcropping sedimentary rocks of different ages in the area (Triassic to Neogene) were selected and analysed. The organic matter was studied by Rock-Eval pyrolysis and under the microscope in reflected non-polarized light and incident blue light. The results obtained show the presence of different types of organic ...... samples analysed. According to the diagram, the Triassic samples are characterized by type II kerogen, the Jurassic samples by type III kerogen, while the kerogen of the Cretaceous sample corresponds to types I and II. �e organic matter of the Eocene sample analysed contains type III kerogen, as does the ...
... diagram, the Triassic samples are characterized by type II kerogen, the Jurassic samples by type III kerogen, while the kerogen of the Cretaceous sample corresponds to types I and IJ. The organic matter of the Eocene sample analysed contains type II kerogen, as does the Miocene coal sample from Gacko. ...Nikoleta Aleksić, Aleksandar Kostić, Miloš Radonjić. "Composition of organic matter and thermal maturity of Mesozoic and Cenozoic sedimentary rocks in East Herzegovina (External Dinarides, Bosnia and Herzegovina)" in Annales Societatis Geologorum Poloniae (2021). https://doi.org/10.14241/asgp.2021.16
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Bridging Computational Lexicography and Corpus Linguistics: A Query Extension for OntoLex-FrAC
OntoLex, dominantni standard zajednice za mašinski čitljive leksičke resurse u kontekstu RDF-a, Linked Data i tehnologija Semantičkog veba, trenutno se proširuje sa posebnim modulom za Frekvencije, Primere i Informacije zasnovane na Korpusu (OntoLex-FrAC). Predlažemo novi komponent za OntoLex-FrAC, koji se bavi inkorporacijom korpusnih upita za (a) povezivanje rečnika sa korpusnim mašinama, (b) omogućavanje RDF baziranih web servisa da dinamički razmenjuju korpusne upite i podatke odgovora, i (c) korišćenje konvencionalnih upitačkih jezika za formalizaciju unutrašnje strukture kolokacija, skica reči i ...standardizacija, digitalna leksikografija, OntoLex, upiti korpusa, povezani podaci, Lingvistički povezani otvoreni podaciChristian Chiarcos, Ranka Stanković, Maxim Ionov, Gilles Sérasset. "Bridging Computational Lexicography and Corpus Linguistics: A Query Extension for OntoLex-FrAC" in Proceedings of the 2024 Joint International Conference on Computational Linguistics, Language Resources and Evaluation (LREC-COLING 2024), Turin, 20-25 May 2024, LREC (2024)
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A tool for identifying the criticality in the disordered systems with metastable dynamics
Svetislav Mijatović, Dragutin Jovković, Sanja Janićević, Stefan Graovac, Đorđe Spasojević. "A tool for identifying the criticality in the disordered systems with metastable dynamics" in Physica A: Statistical Mechanics and its Applications, Elsevier BV (2021). https://doi.org/10.1016/j.physa.2021.125883
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Flyrock induced by blasting in surface mining
Milanka Negovanović, Lazar Kričak, Snežana Ignjatović, Stefan Milanović, Jovan Marković, Nikola Simić, Rade Šarac (2022)Miniranje predstavlja i dalje najefikasniji i najjeftiniji način eksploatacije velikih količina čvrstih mineralnih sirovina na površinskim kopovima. Energija eksplozije se koristi za fragmentaciju čvrste stenske mase do zahtevane granulacije. Pored pozitivnih efekata miniranja, postoje i određeni neželjeni efekti svakog procesa miniranja koji se mogu javiti, a to su: potresi tla, razletanje komada stene, vazdušni udari, otrovni i zagušljivi gasovi i prašina. Razletanje komada stene je nekontrolisano izbacivanje fragmenata odminirane stenske mase i predstavlja jedan od glavnih izvora materijalne štete ...Milanka Negovanović, Lazar Kričak, Snežana Ignjatović, Stefan Milanović, Jovan Marković, Nikola Simić, Rade Šarac. "Flyrock induced by blasting in surface mining" in Rudarski glasnik, Beograd : Rudarski institut (2022). https://doi.org/10.25075/BM.2022.05
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Application of Expansive Mortars for the Formation of Artificial Screens During Blasting in Urban Areas
During construction of buildings in urban areas, sometimes there is a need to blast solid rock mass in the immediate vicinity of the surrounding buildings. In that case, the aim is not only to increase the efficiency of blasting, but also to reduce harmful effects of ground vibration induced by blasting. At the same time, it is very important to protect the buildings located in the safe zone from the blast site as well as remaining rock mass around ...Milanka Negovanović, Lazar Kričak, Stefan Milanović, Nikola Simić, Jelena Majstorović. "Application of Expansive Mortars for the Formation of Artificial Screens During Blasting in Urban Areas" in 31st International Conference Ecological Truth & Environmental Research-EcoTER'24, Sokobanja, 18-21. jun 2024, Bor : Tehnički fakultet u Boru (2024)
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Hypogene speleogenesis related to porphyry magmatic intrusions and its influence on subsequent karst evolution in the Peruvian high Andes
Alexander Klimchouk, David Evans, Sasa Milanovic, Cristian Bittencourt, Mauro Sanchez, F. Carlos Aguirre (2022)Alexander Klimchouk, David Evans, Sasa Milanovic, Cristian Bittencourt, Mauro Sanchez, F. Carlos Aguirre. "Hypogene speleogenesis related to porphyry magmatic intrusions and its influence on subsequent karst evolution in the Peruvian high Andes" in Geomorphology, Elsevier BV (2022). https://doi.org/10.1016/j.geomorph.2022.108488
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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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A Knowledge-Based Approach to Mine Ventilation Planning in Yugoslav Mining Practice
Ventilation system analysis is a complex process based on the calculation and analysis of numerous parameters. These problems can be successfully solved by the SimVent numerical package, but a full understanding and use of the obtained results require the involvement of an experienced specialist in the ventilation field. The solution was found in the creation of a hybrid system INVENTS, whose knowledge base represents a formalization of the expert knowledge in the mine ventilation field. In this paper, we ...... the basis for SimVent is composed of the following: (i) a block for the analysis of air flow and pressure distribution in the ventilation network, (ii) a block for the analysis of climate conditions in mine workings, (iii) a block for temperature and heat depression analysis in fire incidence condi- ...
... 10. R. V. Ramani, K. V. K. Prasad and M. Swaminathan, Implementation of KBS for mine ventilation planning and design, XXII Int. Symp. APCOM, Berlin II (1990) 329–352. 11. E. Rich, Artificial Intelligence (McGraw-Hill, New York, 1983). 12. Z. Y. Yang, I. S. Lowndes and B. Denby, Genetic algorithm o ...Nikola Lilić, Ivan Obradović, Ranka Stanković. "A Knowledge-Based Approach to Mine Ventilation Planning in Yugoslav Mining Practice" in Mineral Resources Engineering 11 no. 4, Imperial College Press (2002): 361-382. https://doi.org/10.1142/S0950609802001014
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Callovian (Middle Jurassic) Sphriganaria (Brachiopoda) from the Jordan Valley (Middle East)
Howard R. Feldman, Barbara V. Radulović, Fayez Ahmad. "Callovian (Middle Jurassic) Sphriganaria (Brachiopoda) from the Jordan Valley (Middle East)" in Historical Biology (2023). https://doi.org/10.1080/08912963.2022.2122823
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Bilingual lexical extraction based on word alignment for improving corpus search
Jelena Andonovski, Branislava Šandrih, Olivera Kitanović. "Bilingual lexical extraction based on word alignment for improving corpus search" in The Electronic Library, Emerald (2019). https://doi.org/10.1108/EL-03-2019-0056
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A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)
... hidrogeološki parametri 1. INTRODUCTION Kolubara Coal Basin (KCB) is the strongest link of the Electric Power Industry of Serbia. Since World War II, it has produced more than 580,000,000 tons of coal. Every other kilowatt in Serbia comes from KCB’s lignite (brown coal). A daily extraction rate of ...Jelena Ratković, Dušan Polomčić, Dragoljub Bajić, Bojan Hajdin. "A hydrogeological model of the open-cast mine Tamnava - West Field (Kolubara Coal Basin, Serbia)" in Underground Mining Engineering no. 29, Belgrade : University of Belgrade - Faculty of mining and geology (2016): 43-54