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334 items
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Extensive vibrations of the belt conveyer drive electromotor of a bucket wheel excavator as a result of intesified wear-and-tear of its mount support
Vesna Damnjanović, Predrag Jovančić, Snežana Aleksandrović. "Extensive vibrations of the belt conveyer drive electromotor of a bucket wheel excavator as a result of intesified wear-and-tear of its mount support" in Journal of Vibroengineering (2017). https://doi.org/10.21595/jve.2016.17321
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The interaction of organoselenium trans-palladium(II) complexes toward small-biomolecules and CT-DNA
Serija organoselenijum trans-paladijum(II) kompleksa 1 (bis(2-(fenilselanilmetil)oksolan)dihloropaladijum(II)), 2 (bis(2-(fenilselanilmetil)oksan)dihloropaladijum(II)) i 3 (bis(2) ,2-dimetil-3-(fenilselanil)oksan)dihloropaladijum(II)) su korišćeni za ispitivanje reaktivnosti ovog specifičnog tipa kompleksa prema različitim bio-molekulima. Ovaj sistem je od posebnog interesa jer se jako malo zna o supstitucionim reakcijam organoselenijum paladijum(II) kompleksa sa trans konfiguracijom. Zamena koordinovanog hlorida sa serijom malih bio-molekula (l-Met, l-His, l-Cis, GSH i 5′-GMP) proučavana je pod uslovima pseudo-prvog reda kao funkcija koncentracije nukleofila i temperature korišćenjem tehnika zaustavljenog toka. Rezultati za proučavane komplekse ukazuju da ...Vera M. Divac, Aleksandar Mijatović, Marina D. Kostić, Jovana Bogojeski. "The interaction of organoselenium trans-palladium(II) complexes toward small-biomolecules and CT-DNA" in Inorganica Chimica Acta, Elsevier BV (2017). https://doi.org/10.1016/j.ica.2017.07.012
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Fragmenting of cylindrical rock specimens under explosive load: Comparison between model and laboratory results
Slavko Torbica, Veljko Lapcevic (2016)Slavko Torbica, Veljko Lapcevic. "Fragmenting of cylindrical rock specimens under explosive load: Comparison between model and laboratory results" in Mining and Metallurgy Engineering Bor (2016). https://doi.org/10.5937/mmeb1601103T
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Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic
Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković (2020)Artificial lift methods have applications in oil wells where oil production is no longer possible due to natural reservoir energy, so this necessary energy is added by introducing lift methods. In order to achieve optimum production, the selection of an artificial lift method is very important. This paper uses fuzzy logic as a mathematical and conceptual model for selection of the optimal artificial lift method. The outcome or IF-THEN rules, as the central part of the model, is based ...... are displayed in a coordinate system that involves the center of mass (weighted mean of maximum) and the mathematical deviation (Figure 7). Energies 2020, 13, 1758 12 of 15 Energies 2020, 13, x 13 of 15 Figure 7. Center of mass and standard deviation outputs for a new well in relation to the ...
... considerable number of parameters being at the limit values (1 or 10). Figure 7. Center of mass and standard deviation outputs for a new well in relation to the standards for the other methods. Center of mass By calculating the weighted mean of maximum, defuzzification is done and the value of the ...
... The center of mass and standard deviation are calculated for each of the model results. The standards of artificial lift methods were obtained by summing together many wells with good results from applying the appropriate method. For each summed surface, we calculated the center of mass and standard ...Miroslav Crnogorac, Miloš Tanasijević, Dušan Danilović, Vesna Karović Maričić, Branko Leković. "Selection of Artificial Lift Methods: A Brief Review and New Model Based on Fuzzy Logic" in Energies, MDPI AG (2020)
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Application of a Method for Intelligent Multi-Criteria Analysis of the Environmental Impact of Tailing Ponds in Northern Kosovo and Metohija
Gordana Milentijević, Blagoje Nedeljković, Milena Lekić, Zoran Nikić, Ivica Ristović, Jelena Đokić (2016)... to Equation (3): CI = λmax − n n − 1 (3) where λmax is maximum value of the evaluation matrix. The closer λmax is to the number of alternatives (n), the less inconsistency there is. λmax is calculated by Equation (4): λmax = 1 n n ∑ i=1 λi (4) By putting λmax from Equation (3) in Equation (4) ...
... highest level Energies 2016, 9, 935 8 of 18 Every comparison of two elements of the hierarchy (model) is done by using Saaty’s scale, expressed by equation [22]. S = { 1 9 , 1 8 , 1 7 , 1 6 , 1 5 , 1 4 , 1 3 , 1 2 , 1, 2, 3, 4, 5, 6, 7, 8, 9 } (1) The basic results of the AHP method are weight ...
... t vectors W recommended by Saaty include summarizing the comparison results’ matrix rows and normalization of the obtained sums, according to the Equation (2): n ∑ j=1 Wi Wj = Wi ( n ∑ j=1 1 Wj ) i = 1, . . . , n (2) The errors in the process of adding values to the elements in coupling comparison ...Gordana Milentijević, Blagoje Nedeljković, Milena Lekić, Zoran Nikić, Ivica Ristović, Jelena Đokić. "Application of a Method for Intelligent Multi-Criteria Analysis of the Environmental Impact of Tailing Ponds in Northern Kosovo and Metohija" in Energies, MDPI AG (2016). https://doi.org/10.3390/en9110935
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Preparation of Multimedia Document “YU Rock Scene”
SUMMARY: This study will present the preparation process of a multimedia document entitled YU ROCK SCENE in which participants were senior students of undergraduate studies of the Department of Library and Information Science at the University of Belgrade Faculty of Philology during the academic year 2014/2015, as a part of the subject Multimedia Documents. This study gives an overview of the historical development of rock and roll in the territory of the former Yugoslavia, rock scene in Yugoslav republics, ...... about success, as well as to the issues of the generation. Number of rock groups and solo performers was increasing, and the 1970s are considered the most fruitful years, since they brought mass production and great popularity to the rock scene. Bands that were established in the beginning of the 1970s were ...
... directions developed in rock and roll music: country pop rock (com- bination of ethno sound and rock style) and the western, mostly Anglo-American rock. Unlike the world rock scene whose texts were a powerful means of propaganda against wars and class conflicts, original domestic rock texts had visual and ...
... were greatly influenced by the hippy movement, but then branching of rock music into sub-branches began, giving rise to hard rock, progressive rock, art rock, jazz, blues and others. At the end of that decade, punk appeared (under the influence of British and American punk bands such as The Sex Pistols ...Milena Obradović, Aleksandra Arsenijević, Mihailo Škorić. "Preparation of Multimedia Document “YU Rock Scene”" in Infotheca - Journal for Digital Humanities, Faculty of Philology, University of Belgrade (2017). https://doi.org/10.18485/infotheca.2016.16.1_2.6
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The external aggregation Newton's method for solving nonlinear equations and applications
Marija Paunović, Dejan Ćebić, Nebojša Ralević. "The external aggregation Newton's method for solving nonlinear equations and applications" in The University Thought - Publication in Natural Sciences, Centre for Evaluation in Education and Science (CEON/CEES) (2020). https://doi.org/10.5937/univtho10-24982
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A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers
Effectiveness evaluation is one of the basic components of engineering asset management and maintenance engineering in general. Effectiveness is an overall concept representing a measurement of quality of service level for the analyzed engineering system. This concept contains a series of partial indicators relating to time in operation and time for maintenance activities, as well as functional properties of the system. This article describes the analysis and structuring of partial indicators, as well as the development of a model ...Miloš Tanasijević, Predrag Jovančić, Dejan Ivezić, Uglješa Bugarić, Radiša Đurić. "A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers" in International Journal of Industrial Engineering: Theory, Applications and Practice (2019)
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Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining
Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović (2019)... done using Equation (3). CI = (λmax − n) (n − 1) (3) where λmax represents the maximum value of the calculated matrix and is defined using Equation (4) while n is the number of analysed objects. λmax = 1 n n∑ i=1 λi (4) The Consistency Ratio (CR) is defined using the following equation: CR = CI ...
... using Equation (3). max(λ n)CI= (n 1) − − (3) where λmax represents the maximum value of the calculated matrix and is defined using Equation (4) while n is the number of analysed objects. n max i i=1 1λ = λ n (4) The Consistency Ratio (CR) is defined using the following equation: CICR= ...
... value that presents priority vector (W). Calculating the priority vector of each element of the analysis by equation number 1 creates the possibility of forming the mathematical matrix M (by Equation (2)). n n i i j jj= 1 j= 1 W 1W = = W i= 1 , . . . ,n W W (1) Figure ...Ivan Janković, Stevan Đenadić , Dragan Ignjatović , Predrag Jovančić , Tomislav Šubaranović, Ivica Ristović . "Multi-Criteria Approach for Selecting Optimal Dozer Type in Open-Cast Coal Mining" in Energies, MDPI (2019). https://doi.org/https://doi.org/10.3390/en12122245
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Fragmentation Size Prediction of Blasted Material Using a Specialized Software for Drilling and Blasting
Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić, Miljan Gomilanović (2024)Design and optimizing the drilling and blasting parameters, should fill the requirements for the capacity, fragmentation size, and technical characteristics of loading and transport equipment, and enable a safe work at the open pit. Besides mentioned, it also achieves the minimal impact on the environment of the open pit and decreases the negative effects on the environment, especially in the blast vibration and flyrock. To obtain the best possible blasting effects and consider all the factors, a specialized software is ...Stefan Milanović, Nikola Simić, Lazar Kričak, Milanka Negovanović, Nikola Đokić, Miljan Gomilanović. "Fragmentation Size Prediction of Blasted Material Using a Specialized Software for Drilling and Blasting" in The 55th International October Conference on Mining and Metallurgy, Mining and Metallurgy Institute Bor (2024). https://doi.org/10.5937/IOC24077M
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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)
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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
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Развој модела конструкције просторија отварања рудника са подземном експлоатацијом
Dražana M. Tošić (2016-08-26)Приликом израде подземних просторија у стјенској маси долази до нарушавања природне равнотеже напонских стања стијенског масива који су владали прије израде тих просторија, при чему долази до појаве прертасподјеле напона и његове концентрације у појединим правцима и тачкама, односно долази до појаве пластичних деформација које су праћене ломљењем стијенске масе и кретањима материјала према откопаном простору...модел, метод коначних елемената, просторија отварања, напон, дефеормација стијенског масива, алгоритам функционалних зависностиDražana M. Tošić. "Развој модела конструкције просторија отварања рудника са подземном експлоатацијом" in Универзитет у Београду, Универзитет у Београду, Рударско-геолошки факултет (2016-08-26)
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The influence of alkyl polyglucosides (and highly ethoxylated alcohol boosters) on the phase behavior of a water/toluene/technical alkyl polyethoxylate microemulsion system
Marija Ilic, Franz-Hubert Haegel, Vesna Pavelkic, Dragan Zlatanovic, Snezana Nikolic-Mandic, Aleksandar Lolic, Zoran Nedic (2016)The influence of additives (alkyl polyglucoside, Glucopon 600 CS UP and alcohol ethoxylate C18E100) on the behavior of the water/toluene/Lutensol ON 50 (technical oxoalcohol, i-C10E5) microemulsion system as a function of temperature and composition has been investigated. The phase behavior of the microemulsions was determined by vertical sections through the Gibbs phase prism (fish-like phase diagrams). Alkyl polyglucoside shifts the one phase region to lower temperatures compared with water/toluene/Lutensol ON 50 mixtures. This is contrary to the expectation, considering ...микроемулзија, толуен, алкил полиглукозид, оксоалкохол етоксилат, појачивач ефикасности, „fish“ дијаграми... constant oil/water ratio as a function of temperature, 7, and surfactant mass fraction, ž, The phase boundaries resemble the shape of a fish. Typically, temperature- -composition phase diagrams obtained for a 1/1 mass ratio of oil and water show a one-phase microemul- sion at relatively high ...
... variables are the temperature and the following composition variables (pressure is always kept constant) - the mass fraction of oil in the mixture of water and oil: 0 = a {(ma + me) () The mass fraction of surfactant in the mixture of all three components in ternary mixtures: = mcel(ma + ma + mc) ...
... order surfactant, toluene, water to suppress intermediate formation of liquid crystals. The mass fraction of the surfactant (or surfactant/additive) is calculated with Eqs. (2) or (3) and the mass fraction of the additive in the surfactant /additive mixture with Eq. (4). Samples were weighed ...Marija Ilic, Franz-Hubert Haegel, Vesna Pavelkic, Dragan Zlatanovic, Snezana Nikolic-Mandic, Aleksandar Lolic, Zoran Nedic. "The influence of alkyl polyglucosides (and highly ethoxylated alcohol boosters) on the phase behavior of a water/toluene/technical alkyl polyethoxylate microemulsion system" in Chemical Industry and Chemical Engineering Quarterly, National Library of Serbia (2016). https://doi.org/ 10.2298/CICEQ141105015I
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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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Development of an integrated model for open-pit-mine discontinuous haulage system optimization
Miodrag Čelebić, Dragoljub Bajić, Sanja Bajić, Mirjana Banković, Duško Torbica, Aleksej Milošević , Dejan Stevanović (2024)Miodrag Čelebić, Dragoljub Bajić, Sanja Bajić, Mirjana Banković, Duško Torbica, Aleksej Milošević , Dejan Stevanović . "Development of an integrated model for open-pit-mine discontinuous haulage system optimization" in Sustainability, MDPI (2024). https://doi.org/10.3390/su16083156
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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... 2 ieff exp � � Ei kT � P i exp � � Ei kT � ; ði ¼ 0; 1; 2 and 3Þ; ð2Þ where gJ represents the Landé splitting factor. Compared to (1), equation (2) contains two additional elements: Mieff (an ‘effective magnetic number’, assigned to its corresponding Kramer’s doublet) and Ei (the energy ...
... doublet, in the same manner as the magnetic quantum numbers MJ do for the Zeeman splitting of a free ion ground level. In most cases, fitting of the equation (2) to experimental data can be difficult, since it assumes a large number of free parameters to be fitted to a relatively flat curve. Even in the ...
... addition, only those crystal field levels that are significantly populated within the considered temperature interval can be ‘observable’ by using equation (2). Thus, its successful appli- cation is limited by the overall number of crystal field levels (number of parameters), the overall width of the ...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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Application of Peleg model on mass transfer kinetics during osmotic dehydratation of pear cubes in sucrose solution
Vesna Pavelkić, Tanja Brdarić, Marija Petrović, Gavrilo Šekularac, Milica Košević, Lato Pezo, Marija Ilić (2015)The applicability of Peleg model was investigated for predicting mass transfer kinetics during the osmotic dehydration (OD) process of pears, at different concentrations (40, 60 and 70%, w/w) and temperatures (20, 35 and 50 °C) of sucrose solution. Increase in sucrose solution concentration resulted in higher water loss (WL) and solid gain (SG) values through the osmotic treatment period. After 360 min of osmotic treatment of pears, WL ranged from 23.71 to 31.68% at 20 °C, from 24.80 to ...Vesna Pavelkić, Tanja Brdarić, Marija Petrović, Gavrilo Šekularac, Milica Košević, Lato Pezo, Marija Ilić. "Application of Peleg model on mass transfer kinetics during osmotic dehydratation of pear cubes in sucrose solution" in Chemical Industry and Chemical Engineering Quarterly (2015). https://doi.org/10.2298/CICEQ141014004P
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Study of the Synergetic Effect of Co-Pyrolysis of Lignite and High-Density Polyethylene Aiming to Improve Utilization of Low-Rank Coal
Ivan Kojić, Achim Bechtel, Nikoleta Aleksić, Dragana Životić, Snežana Trifunović, Gordana Gajica, Ksenija Stojanović (2021)... value; Qn1 = 38.2 × mass proportion of C + 84.9 × (mass proportion of H − mass proportion of O/8)— 0.62 [53]; Qn2 = 34.1 × mass proportion of C + 121.4 × mass proportion of H − 15.3 × mass proportion of O + 10.5 × mass proportion of S [53]; Qn3 = 33.9 × mass proportion of C + 121.5 × mass proportion of H ...
... H − 12.7 × mass proportion of O + 9.3 × mass proportion of S [53]; Qn4 = 33.4 × mass proportion of C + 117.7 × mass proportion of H − 15.6 × mass proportion of O [54]; Qn5 = 33.8 × mass proportion of C + 122.3 × (mass proportion of H − mass proportion of O/8) + 9.4 × mass proportion of S [55]; Qg—gross ...
... Qg—gross calorific value; Qg6 = 33 × mass proportion of C + 120 × mass proportion of H − 16 × mass proportion of O [41]; Qn7 = 35.2 × mass pro- portion of C + 116.2 × mass proportion of H + 6.3 x mass proportion of N + 10.5 x mass proportion of S − 11.1 × mass proportion of O [40,56]; Qg8 = 971 + 323.6 × %C ...Ivan Kojić, Achim Bechtel, Nikoleta Aleksić, Dragana Životić, Snežana Trifunović, Gordana Gajica, Ksenija Stojanović. "Study of the Synergetic Effect of Co-Pyrolysis of Lignite and High-Density Polyethylene Aiming to Improve Utilization of Low-Rank Coal" in Polymers, MDPI AG (2021). https://doi.org/10.3390/polym13050759
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Phase relations and physical indicators of municipal waste from old landfills in Serbia
Due to certain similarities of municipal waste and soil, usually for the determination of basic parameters of physical state, laboratory and field tests which are common in geotechnical investigations are used. It is often to construct an apparatus for special purpose to perform some specific laboratory and field tests. Therefore, different values of indicators of municipal waste physical state can be found in the literature. The basic reasons should be found in different definitions and methods that researchers use ...municipal waste, moisture content, unit weight, specific gravity, grain size distribution, porosityGeneral Computer Science... change in relation to the depth of taken sample. The first phase means heating at a temperature of 55"% to constant mass. In this stage, loss of mass compared to a constant mass is defined as moisture (W). Thereafter, samples are heated to a temperature of 105%C and again masses of separately ...
... of 440% until material reaches constant mass. This method is in accordance with ASTM D2974-87 standard, according to which the content of organic matter (OS) is defined as a relation of mass of lost material smaller than 20 mm and remaining mass of material after heating, at a temperature ...
... to the following expressions: |. O ı_M H[l Ah (1—"0)F n=m An—n„—To Q) 1_Z H() w=w, — 4 G) m where: mx, mya — initial dry mass and mass of drained water Žuo, }a — Initial dry unit weight and dry unit weight in degradation stage no, n — initial porosity and porosity in a certain ...Dragoslav R Rakić, Irena G Basarić Ikodinović, Jovana M Janković, Tina D Đurić. "Phase relations and physical indicators of municipal waste from old landfills in Serbia" in Japanese Geotechnical Society Special Publication, The Japanese Geotechnical Society (2021). https://doi.org/10.3208/jgssp.v09.cpeg016