Претрага
260 items
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Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention
Gas wells, particularly those situated onshore, play a vital role in the global energy sector by supplying a significant portion of natural gas. However, operational challenges, notably gas hydrate formation, pose substantial issues, leading to complications such as flowline blockages and unexpected well shutdowns. Gas hydrates, crystalline structures resembling ice, ...Gas Well, Gas Hydrate Formation, Well Modeling, Well Performance Optimization, Choke Position Adjustments, Methanol InjectionMilica Ješić, Bojan Martinović, Stefan Stančić, Miroslav Crnogorac, Dušan Danilović. "Mitigating hydrate formation in onshore gas wells: A case study on optimization techniques and prevention" in Underground Mining Engineering, Beograd : Rudarsko-geološki fakultet (2023)
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Probabilistic analysis of anisotropic rock slope with reinforcement measures
During the construction of E75 highway through Grdelica gorge in Serbia, a major failure occurred in the zone of reinforced rock slope. Excavation was performed in highly anisotropic Paleozoic schist rock formation. The reinforcement consisted of the two rows of micropile wall with pre-stressed anchors. Forces in anchors were monitored with load cells while benchmarks were installed for superficial displacement measurements. The aim of the study is to investigate possible causes of instability considering different probability distributions of the ...Zoran Berisavljević, Dušan Berisavljević, Miloš Marjanović, Svetlana Melentijević. "Probabilistic analysis of anisotropic rock slope with reinforcement measures" in Geomechanics and Engineering (2023). https://doi.org/10.12989/gae.2023.34.3.285
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Gas-lift wells optimization at the oil field "K"
Dušan Danilović, Marija Ilić, Miroslav Crnogorac, Lola Tomić. "Gas-lift wells optimization at the oil field "K"" in Podzemni radovi, University of Belgrade - Faculty of Mining and Geology (2022). https://doi.org/10.5937/podrad2241031D
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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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Automated blasthole drilling in surface mining
Milanka Negovanović, Lazar Kričak (2021)Све већи развој аутоматизације у рударској индустрији утицао је на увођење нових решења у области аутоматизације бушења минских бушотина на површинским коповима. Највећи светски произвођачи опреме за бушење развијају решења аутоматизације која омогућавају рударским компанијама да постигну најбоље резултате у погледу квалитета, продуктивности и оперативних трошкова. Решења из области аутоматизације бушења се крећу од операција даљинског управљања до потпуно аутоматизованог бушења, праћења података у реалном времену и разних специјализованих алата за управљање подацима који повећавају безбедност и продуктивност ...Аутоматизација, бушилица,тачност, бушење,рударство,систем даљинског управљања,безбедност, продуктивностMilanka Negovanović, Lazar Kričak . "Automated blasthole drilling in surface mining" in 8th International Conference Mining And Environmental Protection, Sokobanja, 22 – 25th September 2021 Serbia, University of Belgrade, Faculty of Mining and Geology, Belgrade, Serbia (2021)
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Long-term planning methodology for improving wood biomass utilization
The insufficiently developed forest management system is often followed by undeveloped forest resources supply chain and insufficient institutional support. These cause inefficient usage of fuel-wood as well as huge amounts of unused forest residues. In order to achieve optimal and long-term sustainable utilisation of biomass, an original methodology based on the interaction of mathematical optimization and backcasting approach has been developed. Mathematical optimization is used for both generation and consideration of techno-economic parameters of the forest biomass supply chain. ...Vladimir Vukašinović, Dušan Gordić, Marija Živković, Davor Koncalović, Dubravka Živković. "Long-term planning methodology for improving wood biomass utilization" in Energy, Elsevier BV (2019). https://doi.org/10.1016/j.energy.2019.03.105
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Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept
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 ...Uroš Đurić, Miloš Marjanović, Zoran Radić, Biljana Abolmasov. " Machine learning based landslide assessment of the Belgrade metropolitan area: Pixel resolution effects and a cross-scaling concept" in Engineering Geology , Elsevier (2019). https://doi.org/10.1016/j.enggeo.2019.05.007
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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... mul- ticriteria optimization was applied to select the best alternative. The fuzzy analytic hierarchy process method was 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 ...
... making model for shipping com- pany performance evaluation. Maritime Policy and Ma- nagement, 28 (4): 375–392. CHU, A., KALABA, R. & SPRINGAM, K. 1979. A comparison of two methods for determining the weights of belong- ing to fuzzy sets. Journal of Optimization Theory and Applications, l27: 531–541 ...
... 03:38:48 Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia Dragoljub Bajić, Dušan Polomčić Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Fuzzy optimization in hydrodynamic analysis ...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
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A Model for Determining Fuzzy Evaluations of Partial Indicators of Availability for High-Capacity Continuous Systems at Coal Open Pits Using a Neuro-Fuzzy Inference System
This paper presents a model for determining fuzzy evaluations of partial indicators of the availability of continuous systems at coal open pits using a neuro-fuzzy inference system. The system itself is a combination of fuzzy logic and artificial neural networks. The system availability is divided into partial indicators. By combining the fuzzy logic and artificial neural networks, a model is obtained that has the ability to learn and uses expert judgment for that learning. This paper deals with the ...системи, континуални системи експлоатације (роторни багер-транспортер-дробилично постројење), рударство, расположивост, меко рачунарство, фази логика, ANN, ANFISMiljan Gomilanović, Miloš Tanasijević, Saša Stepanović, Filip Miletić. "A Model for Determining Fuzzy Evaluations of Partial Indicators of Availability for High-Capacity Continuous Systems at Coal Open Pits Using a Neuro-Fuzzy Inference System" in Energies, MDPI AG (2023). https://doi.org/10.3390/en16072958
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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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Application of stochastic models for mine planning and coal quality control
... nature of mineralization and equipment performance is required in short range than medium range planning. Operational planning is concerned with daily or weekly requirements of the mine. Proper operational planning must conform to short term mine plans as well as satisfying many practical details ...
... seam. Due to the fluctuation of the coal quality, mine planning and coal homogenization are in fact an optimization problem under uncertain conditions. To deal with these issues a stochastic optimization model is developed for an illustrative coal homogeniza- tion problem. Mining block grades from an optimized ...
... Alegre, Brasil, vol. 1, 2007. pp. 378-390 [10] Gershon, M. E., Mine Scheduling Optimization with Mixed Integer Programming, AlME Fall Meeting, Honolulu, Hi., Preprint No. 82- 324, 1982 [11] Padberg, M. W., Linear Optimization and Extensions, Springer, N. Y., USA, 1995 [12] De Wet, N., Homogenizing/Blending ...Dejan Stevanović, Božo Kolonja, Ranka Stanković, Dinko Knežević, Mirjana Banković. "Application of stochastic models for mine planning and coal quality control" in Thermal Science, Belgrade : Vinča Institute of Nuclear Sciences (2014). https://doi.org/10.2298/TSCI130201031S
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Concepts for Improving Machine Learning Based Landslide Assessment
Miloš Marjanović, Mileva Samardžić Petrović, Biljana Abolmasov, Uroš Đurić. "Concepts for Improving Machine Learning Based Landslide Assessment" in Natural Hazards GIS-based Spatial Modeling Using Data Mining Techniques, Advances in Natural and Technological Hazards Research, volume 48, Springer Nature Switzerland AG 2019 (2019). https://doi.org/10.1007/978-3-319-73383-8_2
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Coupling of artificial intelligence methods in the development of hybrid intelligent systems
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... concept in complex mine ventilation network analysis. INVENTS is composed of a number of integrated software packages, which couple both well known numerical optimization and various artificial intelligence methods. By introducing heuristics into the knowledge base existing mathematical models are upgraded ...
... propagation algorithm (starting from a random distribution of weights). In the second one the initial values of network weights were a result of an optimization process performed by GA. These algorithms mimic the natural evolution process. Namely, they optimize a “population” through several “generations” ...
... initial weights of the NN were determined by the genetic algorithm on basis of the training set using the minimum of the mean square error as the optimization criterion. It should be stressed that good result can be achieved through a small number of generations processed by GA, because the error is ...Ranka Stanković, Ivan Obradović, Nikola Lilić. "Coupling of artificial intelligence methods in the development of hybrid intelligent systems" in X Kongres Matematičara, Matematički fakultet, Beograd (2001)
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Značaj izvodjenja Proktorovog opita na komunalnom otpadu
Komunalni otpad predstavlja jedan od ključnih problema današnjice. U Srbiji je najčešći vid odlaganja otpada na komunalne deponije i zbog toga je bitno ispravno i sigurno ga skladištiti. Zbijanje komunalnog otpada predstavlja jednu od osnovnih komponenti procesa odlaganja. Kako bi se što bolje predvidelo ponašanje komunalnog otpada neophodno je pre zbijanja na terenu laboratorijski odrediti maksimalnu suvu zapreminsku težinu i optimalnu vlažnost. U dosadašnjoj praksi u svetu za to se koristi standardizovan Proktorov opit. U radu će biti prikazani ...... available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf.bg.ac.rs See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/340660301 THE IMPORTANCE OF PROCTOR TEST PERFORMANCE ON MUNICIPAL SOLID WASTE ...
... Ministarstva prosvete, nauke i tehnološkog razvoja Republike Srbije. LITERATURA: Cox, J. T., Hanson, J., Yesiller, N., Clarin, J. & Noce, D. E.: Optimization of Compaction Procedures and Waste Placement Operations at MSW Landfills, Global Waste Management Symposium, Orlando, Florida. 2014. Hanson, ...
... zbijanja na terenu laboratorijski odrediti maksimalnu suvu zapreminsku težinu i optimalnu vlažnost. U u Plandištu. THE IMPORTANCE OF PROCTOR TEST PERFORMANCE ON MUNICIPAL SOLID WASTE ABSTRACT Municipal solid waste management is one of the crucial problems worldwide. In Serbia, the most common forms of ...Jovana Janković, Dragoslav Rakić, Tina Đurić, Irena Basarić Ikodinović, Laslo Čaki. "Značaj izvodjenja Proktorovog opita na komunalnom otpadu" in Zbornik radova osmog naučno-stručnog međunarodnog savetovanja - Geotehnički aspekti građevinarstva, Savez građevinskih inženjera Srbije (2019)
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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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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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Utilizing sewage wastewater heat in district heating systems in Serbia: effects on sustainability
Marija Živković, Dejan Ivezić (2021)Transformation of the heating sector is recognized as being essential for ensuring reliable and afordable energy services provided with reduced consumption of energy sources and diminished impact on the environment and less import dependency. The possibility of utilizing energy sources that otherwise would be wasted needs to be considered and treated as a big advantage of district heating systems. Despite many advantages, sewage wastewater heat is still a mostly unused resource at the global level and a totally unused ...рекуперација топлоте из отпадних вода, систем даљинског грејања, топлотне пумпе, енергетске уштеде, емисија угљендиоксида, енергетска безбедност, Србија... emission reduction of absorption waste heat pumps application for space heating. Mateu-Royo et al. (2020) presented the thermo-economic optimization, focusing on performance of the system and environmental analysis. Koll- mann et al. (2017) proposed a novel method to assess the integration of wastewater ...
... Ivezić 1 3 Key performance indicators For the evaluation, comparison and analysis of the current and possible state of district heating systems, three groups of indicators are selected focusing on energy performance, energy supply, and environmental impact. Energy performance The primary energy ...
... on heat pump performance in an Olympic village in Vancouver are given in Fiore and Genon (2014). Technical data and analyses of effectiveness of a heat pump installa- tion in Vladivostok are discussed in Alekseiko et al. (2014). Spatial and temporal considerations of the performance of M. Živković ...Marija Živković, Dejan Ivezić. "Utilizing sewage wastewater heat in district heating systems in Serbia: effects on sustainability" in Clean Technologies and Environmental Policy, Springer Science and Business Media LLC (2021). https://doi.org/10.1007/s10098-021-02063-6
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A Fuzzy Expert Model for Availability Evaluation
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 ...... dependability and quality of service. Availability performance has a decisive influence on the dependability and the quality of service due to the known fact that the machine must be primarily available for operation in order to obtain performance. The achievement of the satisfactory value of the ...
... Situation analysis Fuzzy composition Probab.theory, Stat.processing Best-fit method Linguistic value Decision model, Asset managment, Optimization, Ranking and Selection Verification AVAILABILITY EVALUATION 2 3 4 5 µ (A) 1.00 0 0.50 poor adequate goodaverage excellent 0.75 0.25 1 ...
... for determination of time state picture. The model could be used for preliminary evaluation and decision making concerning to asset managment, optimization, ranking and selection, especially in the cases when reliable recorded data about machines’ operation do not exist. Without any modification, ...Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić. "A Fuzzy Expert Model for Availability Evaluation" in Proceedings of the 2019 20th International Carpathian Control Conference (ICCC), AGH University of Science and Technology, Kraków - Wieliczka, Poland (2019)
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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 ...... for the Selection of an Artificial Lift Method at the Test Well GL oil well in Salman oil field in Iran has been chosen as a test well. The Salman oil field data are given in Table 4. Selection of mentioned method was done using an optimization model based on a multi-criteria analysis, specifically ...
... multidimensionality, subjectivity and indeterminacy. Optimization criteria were taken into account during model development in order to achieve an optimal selection of artificial lift methods by fuzzy logic application. Optimization criteria are well utilization and service ability. Fuzzy logic has a ...
... the artificial lift methods represents the best solution for a new well. Figure 4. Hierarchical structure of fuzzy composition. Energies 2020, 13, 1758 9 of 15 The goal of this synthesis is to give a solution of optimization model. For example, if A1 is medium, A2 is high, A3 is low, B1 is ...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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An Underground Mine Ore Pass System Optimization via Fuzzy 0–1 Linear Programming with Novel Torricelli–Simpson Ranking Function
rudna sipka, optimizacija, fazi linearno programiranje, trouglasti graf, Toričelijeva tačka, funkcija rangiranjaDževdet Halilović, Miloš Gligorić, Zoran Gligorić, Dragan Pamučar. "An Underground Mine Ore Pass System Optimization via Fuzzy 0–1 Linear Programming with Novel Torricelli–Simpson Ranking Function" in Mathematics (2023). https://doi.org/10.3390/math11132914