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1270 items
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The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers
One of the most important prerequisites for the successful operation of the open-cast lignite mine is to carry out all the auxiliary works timely with the necessary quality. The most important and most commonly used auxiliary machines are bulldozers. Engaging time of bulldozers use is in direct relation with the coefficients of the time and capacity utilization of the continuous system for the excavation of coal and tailings, which indicates their importance. More than 100 bulldozers have been hired ...... average costs for strong and very strong dozers operating on open- cast lignite mine: e Average costs for strong dozers are 63.75 €/mh; e Average costs for very strong dozers are 95.12 €/mh. 288 Limiting costs based оп these уајџез аге defined for strong dozers at 70 C/mh and for уегу strong dozers ...
... Kolubara basin during ј1751 ten years of operation This diagram (Figure 7) is used for further analysis related to optimal replacement time. Lower limit of availability for dozer replacement is 0.80. This is limit value for linear correlation of time categories — time in operation, time of planned and ...
... and Occupational Safety” (TR 33039), “Developed new methods for diagnosis and examination mechanical structures” (TR 35040) and a part of the project “Research on possibility for AT (Advanced Technology) rockbolting application in mines for the purpose of increasing work safety and production efficiency” ...Dragan Ignjatović, Predrag Jovančić, Stevan Đenadić, Ivan Janković, Ivica Ristović. "The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers" in 7th International Symposium Mining and Environmental Protection, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2019)
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An Experimental Investigation of the Environmental Risk of a Metallurgical Waste Deposit
Jasmina Dedić , Jelena Djokic , Jovana Galjak, Gordana Milentijević, Dragan Lazarevic, Živče Šarkočević, Milena Lekić (2022)The aim of this study is to investigate the environmental risk of long-term metallurgical waste disposal. The investigated site was used for the open storage of lead and zinc waste materials originating from a lead smelter and refinery. Even after remediation was performed, the soil in the close vicinity of the metallurgical waste deposit was heavily loaded with heavy metals and arsenic. The pollutants were bound in various compounds in the form of sulfides, oxides, and chlorides, as well ...Jasmina Dedić , Jelena Djokic , Jovana Galjak, Gordana Milentijević, Dragan Lazarevic, Živče Šarkočević, Milena Lekić. "An Experimental Investigation of the Environmental Risk of a Metallurgical Waste Deposit" in Minerals, MDPI, Basel, Switzerland. (2022). https://doi.org/10.3390/min12060661
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An optimal sixteenth order family of methods for solving nonlinear equations and their basins of attraction
Dejan Ćebić, Nebojša Ralević, Marina Marčeta. "An optimal sixteenth order family of methods for solving nonlinear equations and their basins of attraction" in Mathematical Communications (2020)
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Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example
Miloš Marjanović, Biljana Abolmasov, Igor Peshevski, James Reeves, Irena Georgievska. "Regional Slope Stability Analysis in Landslide Hazard Assessment Context, North Macedonia Example" in Understanding and Reducing Landslide Disaster Risk, Springer International Publishing (2020). https://doi.org/10.1007/978-3-030-60227-7_29
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Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements
The capacity of the rotor excavator depends largely on the operation of the subsystem for digging. There is a great contribution to the correct and sharp teeth when the capacity is the highest. In the function of time, the teeth become clogged due to abrasive wear, or changes in their geometric shape. To analyze the bucket wheel drive in depend on wear of the cutting elements in this study adaptive neuro fuzzy inference system (ANFIS) approach was implemented. ANFIS ...Filip Miletić, Predrag D. Jovančić, Milos Milovančević, Dragan Ignjatović. "Adaptive neuro-fuzzy prediction of operation of the bucket wheel drive based on wear of cutting elements" in Advances in Engineering Software, Elsevier BV (2020). https://doi.org/10.1016/j.advengsoft.2020.102824
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Classification of Terms on a Positive-Negative Feelings Polarity Scale Based on Emoticons
Mihailo Škorić (2017)The goal of this paper is to draw attention to the possibility of using emoticon-riddled text on the web in language-neutral sentiment analysis. It introduces several innovations in the existing framework of research and tests their effectiveness. It also presents a software tool especially made for that purpose, explains how it builds a database with sentimental value of terms and offers the user manual. Finally, it presents a software tool that tests the new database and gives some examples ...... In 2005 a series of experiments with the classification of mood for internet blog posts was published, and it served as the basis for many future studies (Mishne, 2005). These experiments used records of terms that appear in posts for which the authors themselves claimed were written in and reflected ...
... specifically made for this experiment. – testing values of the terms from the database by comparing them with human assessments and by using the software testing tool that is specif- ically designed for databases that are the product of the first part of the experiment. 2 Preparation for the database creation ...
... appearance of user interface software for text mining. 3.2 The extraction of values from the document Determiners extraction is performed in two steps. The first part of the extraction consists of picking determiners that will be searched for and the values that they stand for. Determiners and values can be ...Mihailo Škorić. "Classification of Terms on a Positive-Negative Feelings Polarity Scale Based on Emoticons" in Infotheca, Faculty of Philology, University of Belgrade (2017). https://doi.org/10.18485/infotheca.2017.17.1.4
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Dehydroicetexanes in sediments and crude oils: Possible markers for Cupressoideae
Hans Peter Nytoft, Geir Kildahl-Andersen, Sofie Lindström, Frode Rise, Achim Bechtel, Danica Mitrović, Nataša Đoković, Dragana Životić, Ksenija A. Stojanović (2019)Two previously unidentified dehydroabietane isomers were isolated from Miocene Serbian lignite and Rhaetian (Late Triassic) coaly mudstones from South Sweden and characterized using NMRspectroscopy as cis- and trans-dehydroicetexane. Both have a 9(10?20)-abeo-abietane or icetexane skeleton, consisting of a 6-7-6 tricyclic framework with seven carbons in ring B instead of the usual six in common diterpanes of the abietane-type. Dehydroicetexanes can be detected using GC-MS-MS in m/z 270?146 chromatograms without interference from dehydroabietane or other isomers. Dehydroicetexanes are often abundant ...Hans Peter Nytoft, Geir Kildahl-Andersen, Sofie Lindström, Frode Rise, Achim Bechtel, Danica Mitrović, Nataša Đoković, Dragana Životić, Ksenija A. Stojanović. "Dehydroicetexanes in sediments and crude oils: Possible markers for Cupressoideae" in Organic Geochemistry, Elsevier BV (2019). https://doi.org/10.1016/j.orggeochem.2019.01.001
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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 ...... interface forms for the ResNet software package. • VENTEX, the diagnostic expert system for the analysis of ventilation systems are developed for IBM PC and compatible computer systems. The object-oriented approach in system structuring and modeling1 was used as the strategy for defining the model ...
... mathematical model used as 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 ...
... system. The system offers safe data archiving for complex data models as this one, as well as all procedures for data manipulation. The use of SQL as a standard query language for data manipulation secures the openness of the hybrid system INVENTS for a connection with different environments. Figure ...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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VENTEX: An Expert System for Mine Ventilation Systems Analysis
Analiza sistema za ventilaciju je komleksan proces, koji bazira na proračunu brojnih parametara, koji se odnose na: stanje mreže, provetrenost, stabilnost sistema, gubitke vazduha, klimatske uslove, gasno stanje, ugroženost od požara i opasne prašine. Navedeni problemi se uspešno rešavaju paketom SimVent, ali potpuno razumevanje i korišćenje dobijenih rezultata zahteva angažovanje iskusnog specijaliste iz oblasti ventilacije. Rešenje je nađeno u kreiranju ekspertnog sistema VENTEX, čija je baza znanja formalizacija ekspertskog znanja iz oblasti ventilacije rudnika. U radu je prikazana metodologija ...... Измењено: 2023-10-14 04:20:47 VENTEX: An Expert System for Mine Ventilation Systems Analysis Ranka Stanković, Nikola Lilić, Ivan Obradović Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] VENTEX: An Expert System for Mine Ventilation Systems Analysis | Ranka Stanković ...
... ventilation systems analysis is the evaluation of the general ventilation state of the mine. An appropriate and reliable solution for this problem is vital for the safety of the working process in mines with underground exploitation. Contemporary mining theory already operates with a number ...
... interface and a working memory, but also a module for the interface with SimVent numerical routines, the simulation routines themselves, and a data base used by these routines /Fig. 3/. The main purpose of the user interface is to provide means for a successful dialogue, i.e. an exchange of ...Ranka Stanković, Nikola Lilić, Ivan Obradović. "VENTEX: An Expert System for Mine Ventilation Systems Analysis" in YU Info '96 Brezovica, Društvo za informacione sisteme i računarske mreže (1996)
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Polyhedral characteristics of the cosalite-type crystal structures
Sabina Kovač, Predrag Dabić, Aleksandar Kremenović, Aleksandar Pačevski, Ljiljana Karanović, Marko V. Rodić, Martina Tribus (2019)Sabina Kovač, Predrag Dabić, Aleksandar Kremenović, Aleksandar Pačevski, Ljiljana Karanović, Marko V. Rodić, Martina Tribus. "Polyhedral characteristics of the cosalite-type crystal structures" in The Canadian Mineralogist, Mineralogical Association of Canada (2019). https://doi.org/10.3749/canmin.1900017
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Models of Determining the Parameters of Rock Mass Oscillation Equation with Experimental and Mass Blastings
... Minerals 2018, 8, 70 2 of 18 that this is the parameter which best defines danger from shock and damages it may cause. Due to that, adequate standards for the protection from shock are based on data that refer to oscillation velocity [2,3]. As the relation between the rock mass oscillation velocity ...
... . . , vN be the rock mass oscillation velocity values obtained for corresponding reduced distances R1, R2, . . . , RN. Proceeding from the equation for the rock mass oscillation velocity, given by the Equation (1) we can assume, that for pairs (Rm, vm) the following relations are valid: vm = K·Rm −n ...
... blasting conditions and geological characteristics of the rock mass, and it is determined based on trial blasting for a specific work environment. Thus, this paper offers analysis of the method for determination of parameters of the rock mass oscillation equation, which are conditioned by rock mass properties ...Suzana Lutovac, Branko Gluščević, Rade Tokalić, Jelena Majstorović, Čedomir Beljić. "Models of Determining the Parameters of Rock Mass Oscillation Equation with Experimental and Mass Blastings" in Minerals, Basel : MDPI AG, Basel, Switzerland (2018). https://doi.org/10.3390/min8020070
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An Efficient Class of Iterative Root-Finding Methods with Applications
Dejan Ćebić, Nebojša Ralević (2021)Dejan Ćebić, Nebojša Ralević. "An Efficient Class of Iterative Root-Finding Methods with Applications" in 2021 IEEE 19th International Symposium on Intelligent Systems and Informatics (SISY), IEEE (2021). https://doi.org/10.1109/SISY52375.2021.9582495
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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
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Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete
Milan Kragović, Nenad Ristić , Jelena Gulicovski, Andrijana Nedeljković, Snežana Pašalić, Ivica Ristović, Marija Stojmenović (2021)sagorevanje lignita, otpadna šljaka, zamena cementa, proizvodnja maltera i betona, fizičko-mehanička i fizičko-hemijska karakterizacija... carried out. For that purpose, the optimal conditions for the practical application in mortar and concrete production are defined. Tests related to the use of waste slag as a partial replacement for cement in the production of mortars and concrete are performed in accordance with certain standards, and the ...
... determined in accordance with standard EN 1015-10, on the specimens used for testing of mechanical strengths, e.g., on the prisms with dimensions 40 mm × 40 mm × 160 mm. Flexural strength was determined in accordance with standards EN 196-1, EN 1015-11 and was tested on the prisms with dimensions 40 mm ...
... 003. Superplasticizer was used for the improvement of the consistency of fresh concrete and the same quantity was added to all concrete mixtures. Mix proportions of concrete mixtures for 1 m3 of concrete are given in Table 3. Table 3. Mix proportion of concrete mixtures for 1 m3 of concrete. Component ...Milan Kragović, Nenad Ristić , Jelena Gulicovski, Andrijana Nedeljković, Snežana Pašalić, Ivica Ristović, Marija Stojmenović . "Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete" in Minerals, MDPI (2021). https://doi.org/10.3390/min11090925
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Paleomagnetic evidence for post-collisional Miocene clockwise rotation in the Serbian segment of the Vardar Zone and the Danubicum
Vesna Lesić, Emő Márton, Vesna Cvetkov, Dragana Tomić. "Paleomagnetic evidence for post-collisional Miocene clockwise rotation in the Serbian segment of the Vardar Zone and the Danubicum" in 26th IUGG General Assembly Prague, Czech Republic, International Union of Geodesy and Geophysics (2015)
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Improving efficiency of thermal power plants through mine coal quality planning and control
Главни циљ контроле квалитета угља у рудницима лигнита је снабдевање термоелектрана угљем чији квалитет мора да се креће унутар одређених квалитативних ограничења. Карактеристике угља могу да утичу на ефикасност, поузданост и расположивост како котла тако и јединица за контролу емисије. У овом раду аутори су презентовали интегрисану симулацију рударског процеса као нови приступ у истраживању променљивости калоричне вредности угља приликом експлоатације комплексног лежишта лигнита. Резултати таквог приступа омогућавају драгоцен увид у перформансе континуалног рударског система у смислу контроле променљивости ...Mirjana Banković, Dejan Stevanović, Milica Pešić, Aleksandra Tomašević, Ljiljana Kolonja. "Improving efficiency of thermal power plants through mine coal quality planning and control" in Thermal Science, Vinča Institute of Nuclear Sciences (2018). https://doi.org/10.2298/TSCI170605209B
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Spatial assessment of the areas sensitive to degradation in the rural area of the municipality Čukarica
Nature and Landscape Conservation, Soil Science, Agronomy and Crop Science, Water Science and TechnologyNatalija Momirović, Ratko Kadović, Veljko Perović, Miloš Marjanović, Aleksandar Baumgertel. "Spatial assessment of the areas sensitive to degradation in the rural area of the municipality Čukarica" in International Soil and Water Conservation Research, Elsevier BV (2019). https://doi.org/10.1016/j.iswcr.2018.12.004
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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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The subthermal potential of karstic groundwater of Kučaj–Beljanica region in Serbia estimated by the multivariate analysis
Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary ChangeLjiljana Vasić, Dragana Ž. Živojinovic, Vladana Rajaković-Ognjanović, Huang Fen, Cao Jianhua. "The subthermal potential of karstic groundwater of Kučaj–Beljanica region in Serbia estimated by the multivariate analysis" in Environmental Earth Sciences, Springer Science and Business Media LLC (2021). https://doi.org/10.1007/s12665-021-09392-1
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Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia
Dragoljub Bajić, Dušan Polomčić (2014)A groundwater control system was designed to lower the water table and allow the pumping sta-tion “Bezdan 1” to be built. Based on a hydrodynamic analysis that suggested three alternative solutions, mul-ticriteria optimization was applied to select the best alternative. The fuzzy analytic hierarchy process methodwas used, based on triangular fuzzy numbers. An assessment of the various factors that influenced the selec-tion of the best alternative, as well as fuzzy optimization calculations, yielded the “weights” of the alternativesand the ...groundwater lowering, groundwater management scenario, fuzzy analytic hierarchy process,expert knowledge, triangular fuzzy numbers, linguistic variables... (2003) introduced statistical methods to FAHP, for selecting the criterion that affected the end result (i.e. selection of alternative). Among the FAHP approaches mentioned above, the one devised by CHANG (1996) was used to arrive at the best alterna- tive for the groundwater control system of the “Be- ...
... a groundwater control system for the “Bezdan 1” PS, whose function is to lower the water table to below the design eleva- tion, so that the pumping station can be built. Three alternatives were considered, to ensure protection against groundwater intrusion and provide for unhin- dered construction of ...
... water table of the analyzed alternatives. For each alternative, the characteristics of the groundwater control system: the number of wells and their spatial distribution, and the time need- ed to achieve maximal lowering of the water table below the excavation for the “Bezdan 1” PS, were defined as follows: ...Dragoljub Bajić, Dušan Polomčić. "Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia" in Geološki anali Balkanskoga poluostrva, Belgrade : University of Belgrade - Faculty of mining and geology (2014). https://doi.org/10.2298/GABP1475103B