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Упит dcterms_subject_txt:Mechanical Engineering

579 items

  • Fuzzy Model for Risk Assessment of Machinery Failures

    Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković (2020)
    The main goal of this research was the development of an algorithm for the implementation of negative risk parameters in a synthesis model for a risk level assessment for a specific machine used in the mining industry. Fuzzy sets and fuzzy logic theory, in combination with statistical methods, were applied to analyze the time picture state of the observed machine. Fuzzy logic is presented through fuzzy proposition and a fuzzy composition module. Using these tools, the symmetric position of the ...
    fazi teorija, rizik, otkaz rudarskih mašina
    ... Estimation of Mechanical Components of Bucket Wheel Excavator. Ph.D. Thesis, Faculty of Mining and Geology, University of Belgrade, Belgrade, Serbia, 2007. 6. Subašić, P. Fuzzy Logic and Neural Networks; Technical Book: Belgrade, Serbia, 1997; pp. 35–90. 7. Cai, K.Y. System failure engineering and fuzzy ...
    ... based on this high risk. The proposed risk assessment model is useful for any engineering system. Keywords: fuzzy theory; risk; mining machinery failure 1. Introduction Sudden failures of different parts of engineering systems are everyday occurrences in the mining industry, and they often lead to ...
    ... based on this high risk. The proposed risk assessment model is useful for any engineering system. Keywords: fuzzy theory; risk; mining machinery failure 1. Introduction Sudden failures of different parts of engineering systems are everyday occurrences in the mining industry, and they often lead to ...

  • Karst wastewater as a high quality, renewable and within the circular economy water resource

    Jovana Nikolić, Vesna Ristić Vakanjac (2021)
    High quality drinking water in it’s natural state is becoming less and less available to the human population. Based on the expected climate changes, it is considered that this resource will be less in the world but also in our region. Also, the accompanying polluting components that exceed the maximum allowable concentration are increasingly present in the waters. Even after the water treatment, it happens that some components are still in the drinking water, which adversely affects human health. ...
    water resource, groundwater, karst aquifer, water supply, irrigation

  • Application of the principle of circular economy to the thermal groundwater, the example of the municipality of Bogatić

    Marija Jovanović, Vesna Ristić Vakanjac (2021)
    There are about 360 locations of thermal and thermo-mineral waters in Serbia, whose water temperatures range from 14 to 98°C, which ranks Serbia as the richest European country in geothermal energy. The mentioned water resources (thermal and thermomineral waters) are used, mostly, for therapeutic purposes in spas and sports and recreational centers. The main problem that is present is the fact that they are not used in a rational and efficient way. The paper will give examples territorially related ...
    water-food-energy nexus, geothermal resources, groundwater management, sustainability, Bogatić

  • Transformer-Based Composite Language Models for Text Evaluation and Classification

    Mihailo Škorić, Miloš Utvić, Ranka Stanković (2023)
    Parallel natural language processing systems were previously successfully tested on the tasks of part-of-speech tagging and authorship attribution through mini-language modeling, for which they achieved significantly better results than independent methods in the cases of seven European languages. The aim of this paper is to present the advantages of using composite language models in the processing and evaluation of texts written in arbitrary highly inflective and morphology-rich natural language, particularly Serbian. A perplexity-based dataset, the main asset for the ...
    General Mathematics, Engineering (miscellaneous), Computer Science (miscellaneous)

  • Coupling of artificial intelligence methods in the development of hybrid intelligent systems

    Ranka Stanković, Ivan Obradović, Nikola Lilić (2001)
    In this paper we present an approach which couples various artificial intelligence (AI) methods in the solution of complex problems that cannot adequately be solved by a single AI method. We argue that the resulting, hybrid intelligent systems (HIS) can be successfully implemented with the use of available AI software libraries. Different coupling methods are analyzed and a classification of hybrid systems based on the chosen method is given. Two case studies of hybrid systems used in mining engineering ...
    hibridni inteligentni sistemi, spregnuti sistemi, metode veštačke inteligencije, rudarske primene veštačke inteligencije
    ... methods are analyzed and a classification of hybrid systems based on the chosen method is given. Two case studies of hybrid systems used in mining engineering are presented: a system for planing and analysis of mine ventilation, as an example of intercommunicating hybrid systems, and a system for the ...
    ... intelligent systems which couple expert systems, neural networks and genetic algorithms in order to solve some complex problems in the area of mining engineering. In the realization of these systems we have used existing software: the Kappa-PC expert system shell, and the dynamic libraries for neural networks ...
    ... 3. A hybrid system for mine ventilation planing and analysis Ventilation planing and analysis is one of the most complex problems in mining engineering. We approached it by decomposing the global problem into several tasks, each of them solvable by a different method. These methods were then ...

  • Constitutive Model for Analysis of Long-Term Municipal Solid Waste Landfill Settlement

    Irena Basarić Ikodinović, Dragoslav Rakić, Mirjana Vukićević, Sanja Jocković, Jovana Janković Pantić (2022)
    Large long-term settlement occurs at the municipal solid waste landfills over an extended period of time which may lead to breakage of the geomembrane, damage of the cover systems, other protective systems or facilities constructed on top of a landfill. Also, municipal solid waste is an extremely heterogeneous material and its properties vary over location and time within a landfill. These material characteristics require the formulation of a new constitutive model to predict the long-term settlement of municipal solid ...
    constitutive model, finite element analysis, municipal solid waste, settlement

  • Parallel Stylometric Document Embeddings with Deep Learning Based Language Models in Literary Authorship Attribution

    Mihailo Škorić, Ranka Stanković, Milica Ikonić Nešić, Joanna Byszuk, Maciej Eder (2022)
    This paper explores the effectiveness of parallel stylometric document embeddings in solving the authorship attribution task by testing a novel approach on literary texts in 7 different languages, totaling in 7051 unique 10,000-token chunks from 700 PoS and lemma annotated documents. We used these documents to produce four document embedding models using Stylo R package (word-based, lemma-based, PoS-trigrams-based, and PoS-mask-based) and one document embedding model using mBERT for each of the seven languages. We created further derivations of these ...
    General Mathematics, Engineering (miscellaneous), Computer Science (miscellaneous)

  • How active is recent tectonics in the central Balkans: Evidence from the Serbian Carpatho-Balkanides

    Ana Mladenović (2022)
    Since the Late Cretaceous, after closure of the Neotethys ocean, tectonic processes in the central Balkan Peninsula were mainly controlled by the mutual interaction of the Adriatic and the Eurasian plates, and tectonic units in-between. Most of the tectonic structures that have been active during Cenozoic times were inherited from previous tectonic stages under different tectonic regimes. Tectonic activity within the Carpatho-Balkan orogen in eastern Serbia since Miocene is conditioned by the existence of the rigid Moesian promontory east ...

  • Novel cerium and praseodymium doped phosphate tungsten bronzes: Synthesis, characterization, the behavior in the Briggs-Rauscher reaction and photoluminescence properties

    Tijana Maksimović, Pavle Tančić, Jelena Maksimović, Dimitrije Mara, Marija Ilić, Rik Van Deun, Ljubinka Joksović, Maja Pagnacco (2023)
    Due to the interesting and potentially useful properties, phosphate tungsten bronzes are constantly being studied and attract a lot of attention. In the present work, two different metallic elements, belonging to the group of rare-earth metals, cerium and praseodymium, were used as a dopants for phosphate tungsten bronzes. Novel cerium and praseodymium doped phosphate tungsten bronzes were successfully synthesized and further characterized by thermal analyses, Fourier-transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy with energy-dispersive X-ray spectrometer and ...
    Electrical and Electronic Engineering, Atomic and Molecular Physics and Optics, Electronic, Optical and Magnetic Materials, Inorganic Chemistry, Organic Chemistry, Physical and Theoretical Chemistry, Spectroscopy

  • Determining the Availability of Continuous Systems at Open Pits Applying Fuzzy Logic

    Miljan Gomilanović, Miloš Tanasijević, Saša Stepanović (2022)
    This work presents a model for determining the availability of continuous systems at open pits by applying fuzzy logic and fuzzy inference systems. The applied model was formed by the synthesis of independent partial indicators of availability. The model is based on an expert system for assessing the availability of continuous mining systems. The availability of the system, as a complex state parameter, is decomposed into the partial indicators, reliability, and convenience of maintenance, and the fuzzy compositions, used ...
    системи, континуални систем експоатације, површински коп, рударство, расположивост, фази логика, max–min композиција, min–max композиција

  • Compaction of Municipal Solid Waste

    Jovana Janković Pantic, Dragoslav Rakić, Tina Đurić, Irena Basarić Ikodinović, Snežana Bogdanović (2022)
    Regardless of the numerous activities undertaken to reduce municipal solid waste, its annual volumes continue to grow. In Serbia, the most common and the only one form of waste disposal is at municipal landfills with daily compaction and soil covering. Municipal waste compacting is one of the basic components of the disposal process. Well compacted waste takes up less volume and allows much safer storage. In order to better predict the behavior of municipal waste at landfills, it is ...
    compaction, hammer with spikes, landfill, municipal solid waste, proctor compaction test

  • Climate change and their imapct on karst groundwater

    Milan Đelić, Vesna Ristić Vakanjac (2021)
    In the last 30 years, there have been progressively more dry and rainy years, a reduced presence or even absence of snow cover, an increase in air temperature, large-scale fires, intensified glacier melting, and the like. Climate change certainly has an effect on all areas of economic activity, but its largest impact is on water resources and existing ecosystems. One of the most important water resources is groundwater, on account of which more than 70% of the population of ...
    climate change, aquifers, groundwater regime, vulnerability, karst

  • Developing Students’ Mining and Geology Vocabulary Through Flashcards and L1 in the CLIL Classroom

    Lidija Beko, Ivan Obradović, Ranka Stanković (2015)
    ... Ljiljana Kolonja. 2012. Towards a Mining Equipment Ontology. Paper presented at the 12th International Conference Research and Development in Mechanical Industry RaDMI, September in Vrnjačka Banja, Serbia. M31; ISBN: 978-86-6075-036-7 Stanković Ranka, Ivan Obradović, Olivera Kitanović and Ljiljana ...
    ... Conference on Teaching English for Specific Purposes and New Language Learning Technologies, May, 22-24, 2015, Niš, Serbia, Faculty of Electronic Engineering, University of Niš | 2015 | | http://dr.rgf.bg.ac.rs/s/repo/item/0001754 Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду ...
    ... Repository is available at: www.dr.rgf.bg.ac.rs The Second International Conference on Teaching English for Specific Purposes Faculty of Electronic Engineering University of Niš, Serbia May, 22nd to 24th, 2015. Developing students’ mining and geology vocabulary through flashcards and L1 in the CLIL ...

  • A Fuzzy Expert Model for Availability Evaluation

    Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić (2019)
    Each technical system within itself carries the great potential danger of possible occurrence of failure and damages. Mining machines are characteristic by great investment values, costs of unplanned shutdowns, complex working conditions, and environment and workers hazards. Systematic monitoring of the mining machinery is of great importance for the management of the mining companies. Availability is the overall concept of quality of service. Includes information regard to operating state, an idle state, a standby state and shut down. The ...
    raspoloživost, ekspertski sistem, fazi teorija, buldozeri
    ... the working environment. Availability is an integral and important component of life cycle management for numerous engineering systems. This is quite a familiar term in engineering communication. This article described an expert’s system for availability evaluation and model for availability calculation ...
    ... be implemented to other engineering systems or products. REFERENCES [1] Tanasijević M., Ivezić D., Jovančić P., Ćatić D., Zlatanović D., Study of Dependability Evaluation for Multi-hierarchical Systems Based on Max–Min Composition, Quality and Reliability Engineering International, 29(3), 317-326 ...
    ... fuzzy sets to safety and reliability engineering, International Journal of Approximate Reasoning, Vol. 100, Pages 29-55, 2018. [8] Wang, J., Yang, J.B., Sen, P. Safety analyses and synthesis using fuzzy sets and evidential reasoning. Reliability Engineering and System Safety, 47(2), 103-118, 1995 ...

  • Geotechnical Conditions for Construction of Savski Trg Metro Station as a Part of the Belgrade Metro Line One

    Nemanja Stanic, Dragoslav Rakic, Josip Isek, Slavoljub Simic (2024)
    In order to solve serious traffic congestion in Belgrade, a number of studies regarding the Belgrade Metro construction have been carried out since 1973. However, only in 2019, the routes of the future metro lines 1 and 2 were de-fined as a part of the General Metro Construction Project. The lines are de-signed to intersect at the location of Sava Square, where an interchange met-ro station will be built. It represents a complex geotechnical structure consist-ing of three different ...
    metro station, geotechnical modelling, displacements

  • Results of comprehensive monitoring activities on Umka landslide, Belgrade, Serbia

    Biljana Abolmasov, Uroš Đurić (2021)
    klizišta, monitoring
    ... SAROGLOU N. DEPOUNTIS G. PAPATHANASSIOU 3% EUROPEAN REGIONAL CONFERENCE OF THE INTERNATIONAL ASSOCIATION FOR ENGINEERING GEOLOGY & THE ENVIRONMENT Leading to Innovative Engineering Geology Practices VOLUME 1 Extended Abstracts Proceedings Organised by the National Group of Greece of IAEG ...
    ... Đurić2 1University of Belgrade, Faculty of Mining and Geology, Serbia, biljana.abolmasov@rgf.bg.ac.rs 2University of Belgrade, Faculty of Civil Engineering, Serbia, udjuric@grf.bg.ac.rs Background The Umka landslide is the deepest and biggest active landslide in the Republic of Serbia and has ...

  • Permanent GNSS monitoring of landslide Umka

    Mileva Samardžić Petrović, Jovan Popović, Uroš Đurić, Biljana Abolmasov, Marko Pejić, Miloš Marjanović (2020)
    Клизиште Умка је једно од највећих насељених активних клизишта у Србији. Активност клизишта Умка се прати већ више од 85 година, различитим геотехничким и геодетским техникама. Од 2010. године, активност kлизишта се континуирано прати у реалном времену аутоматизованим перманентним системом за праћење базираним на Глобалним навигационим сателитским системима (ГНСС). Поред тога, од 2018. године активност клизишта се додатно прати кинематичким ГНСС одређивањем положаја скупа карактеристичних тачака као и применом UAV фотограметрије. Главни циљ овог рада је приказ резултата опажања три ...
    клизиште, перманентно праћење, ГНСС
    ... Samardžić-Petrović, mimas@grf.bg.ac.rs, Faculty of Civil Engineering, University of Belgrade Jovan Popović, popovic@grf.bg.ac.rs, Faculty of Civil Engineering, University of Belgrade Uroš Đurić, udjuric@grf.bg.ac.rs, Faculty of Civil Engineering, University of Belgrade Biljana Abolmasov, biljana ...
    ... biljana.abolmasov@rgf.bg.ac.rs, Faculty of Mining and Geology, University of Belgrade Marko Pejić, mpejic@grf.bg.ac.rs, Faculty of Civil Engineering, University of Belgrade Miloš Marjanović, milos.marjanovic@rgf.bg.ac.rs, Faculty of Mining and Geology, University of Belgrade PERMANENT GNSS MONITORING ...
    ... technology for data processing in real time, a wide range of different types of complex monitoring automated systems found its use in various engineering disciplines. The Global Navigation Satellite System (GNSS) based monitoring system is one of the widely used systems, used in order to assess ...

  • Хазард од клизишта у Србији у 21. веку

    Biljana Abolmasov (2019)
    клизишта, хазард од клизишта, промене климе
    ... scales. Engineering Geology 102: 164 177. Corominas J., van Westen, Frattini P., Cascini L., Malet JP., Foto Van Den Eechaut M., Mavrouli O., Agliardi F., Pitikalis K., Winte Ferlisi S., Tofani V., Hervas J., Smith JT. (2014). Recommendations analysis of landslide risk. Bulleting of Engineering Geology ...
    ... Natural Hazards 3. UNESCO Press, Paris. 63 pp. [9] Aleotti P., Chowdhury R. (1999). Landslide hazard assessment:summar new perspectives. Bulletin of Engineering Geology and the Environm [10] Guzzetti F, Carrara A, Cardinalli M, Reichenbach P. (1999). Lan evaluation: a review of current techniques and their ...
    ... Natural Hazards 3. UNESCO Press, Paris. 63 pp. Aleotti P., Chowdhury R. (1999). Landslide hazard assessment: summa new perspectives. Bulletin of Engineering Geology and the Environ Guzzetti F, Carrara A, Cardinalli M, Reichenbach P. (1999). Lal evaluation: a review of current techniques and their applicatior ...

  • 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 ...
    raspoloživost, fazi teorija, AHP višekriterijumska analiza, eksperska ocena, buldozer
    ... Serbia; dragan.ignjatovic@rgf.bg.ac.rs (D.I.); milos.tanasijevic@rgf.bg.ac.rs (M.T.); tomislav.subaranovic@rgf.bg.ac.rs (T.S.) 2 Faculty of Mechanical Engineering, University of Belgrade, 11000 Belgrade, Serbia; ubugaric@mas.bg.ac.rs 3 Ministry of Mining and Energy, 11000 Belgrade, Serbia; ivan.jankovic@mre ...
    ... Serbia; dragan.ignjatovic@rgf.bg.ac.rs (D.1.); milos.tanasijevic@rgf.bg.ac.rs (M.T.); tomislav.subaranovic@rgf.bg.ac.rs (T.S.) Faculty of Mechanical Engineering, University of Belgrade, 11000 Belgrade, Serbia; ubugaric@mas.bg.ac.rs Ministry of Mining and Energy, 11000 Belgrade, Serbia; ivan.jankovic@mre ...
    ... 24 October 2019 ���������� ������� Abstract: 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 ...

  • Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept

    Uroš Đurić, Miloš Marjanović, Zoran Radić, Biljana Abolmasov (2019)
    Improvements of Machine Learning-based landslide prediction models can be made by optimizing scale, customizing training samples to provide sets with the best examples, feature selection, etc. Herein, a novel approach, named Cross-Scaling, is proposed that includes the mixing of training and testing set resolutions. Hypothetically, training on a coarser resolution dataset and testing the model on a finer resolution should help the algorithm to better generalize ambiguous examples of landslide classes and yield fewer over/underestimations in the model. This ...
    klizišta, podložnost, mašinsko učenje