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615 items
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Hydrodynamic analysis of radial collector well ageing at Belgrade well field
The origin and effect of hydraulic resistances on the rate of ageing of radial collector wells are identified through numerical hydrodynamic analysis. The research includes hydrodynamic modeling of one such well with new laterals at Belgrade well field. The performance of the laterals is aggravated by rapid ageing. The change in the hydraulic parameters of the laterals during the first decade of operation is analyzed through simulations of the groundwater regime with realistically specified geometries and hydraulics of the ...Đorđije Božović, Dušan Polomčić, Dragoljub Bajić, Jelena Ratković. "Hydrodynamic analysis of radial collector well ageing at Belgrade well field" in Journal of Hydrology, Elsevier BV (2019). https://doi.org/10.1016/j.jhydrol.2019.124463
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A comparison between ARIMA, LSTM, ARIMA-LSTM and SSA for cross-border rail freight traffic forecasting: the case of Alpine-Western Balkan Rail Freight Corridor
Miloš Milenković, Miloš Gligorić, Nebojša Bojović, Zoran Gligorić. "A comparison between ARIMA, LSTM, ARIMA-LSTM and SSA for cross-border rail freight traffic forecasting: the case of Alpine-Western Balkan Rail Freight Corridor" in Transportation Planning and Technology, Informa UK Limited (2023). https://doi.org/10.1080/03081060.2023.2245389
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INVENTS: A Hybrid Mine Ventilation Planning and Design System
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 ...... design process. In the planning process key relations are defined that have to be taken into account in the mine design phase. The initial step in the mine ventilation planing and design process is the establishment of a basic or initial network and an appropriate database related to this network. The ...
... ventilation network, 2. a block for the analysis of climate conditions in mine chambers, 3. a block for temperature and heat depression analysis in fire incidence conditions, 4. a block for gas distribution analysis in the ventilation network. All blocks are mutually interactively connected and the ...
... flow quantities INVENTS ResNet SimVent VENTEX defining basic network resistance ventilation system estimation ventilation simulation Design CFD Estimates estimation of gas and dust emission and temperature conditions flow process modelling using CFD Data acquis ition ventilation and psy ...Lilić Nikola, Stanković Ranka, Obradović Ivan. "INVENTS: A Hybrid Mine Ventilation Planning and Design System" in Proceedings of International Scientific Conference of FME Session 4: Automation Control and Applied Informatics , Hong Kong : iConcept Press (2013)
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INVENTS: a hybrid system for subsurface ventilation analysis
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 ...... design process. In the planning process key relations are defined that have to be taken into account in the mine design phase. The initial step in the mine ventilation planing and design process is the establishment of a basic or initial network and an appropriate database related to this network. The ...
... ventilation network, 2. a block for the analysis of climate conditions in mine chambers, 3. a block for temperature and heat depression analysis in fire incidence conditions, 4. a block for gas distribution analysis in the ventilation network. All blocks are mutually interactively connected and the ...
... flow quantities INVENTS ResNet SimVent VENTEX defining basic network resistance ventilation system estimation ventilation simulation Design CFD Estimates estimation of gas and dust emission and temperature conditions flow process modelling using CFD Data acquis ition ventilation and psy ...Nikola Lilić, Ranka Stanković, Ivan Obradović. "INVENTS: a hybrid system for subsurface ventilation analysis" in Proc. of International Scientific Conference of FME, September 2000, Ostrava, FME (2000)
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Formative evaluation of e-learning projects with the logical framework approach
... framework envisages a network of nodes offering OER content and a central repository, the BAEKTEL Metadata Portal (BMP), where metadata, providing all important information on the network resources will be stored, thus enabling their centralized search and browse. The initial network consists of six ...
... programs are focused on the consequences (outcomes) instead of results (outputs) [13]. Moreover a project is usually linear in producing effects, while a program, has not linear relations mechanism between outputs and effects [9]. 3. EVALUATION OF AN E-LEARNING PROJECT Although there ...
... initiated with the main goal of building an Open Educational Resource (OER) network offering educational materials by higher education (HE) institutions and best practice examples by enterprise experts. The network is conceived as multilingual, which means that resources can be published in ...Roberto Linzalone, Giovani Schiuma, Ivan Obradović, Ranka Stanković. "Formative evaluation of e-learning projects with the logical framework approach" in The Sixth International Conference on e-Learning (eLearning-2015), September 2015, Belgrade, Serbia, Belgrade Metropolitan Univesity (2015)
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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 ...... ventilation network, (ii) a block for the analysis of climate conditions in mine workings, (iii) a block for temperature and heat depression analysis in fire incidence condi- tions, and (iv) a block for gas distribution analysis in the ventilation network, which are interactively connected. SimVent ...
... activity for the design process. In the plan- ning phase, the key relations that have to be taken into account during the design phase are identified. The first activity in the mine ventilation planning and design process is the establishment of a basic or initial ventilation network and an appro- priate ...
... definition of mine venti- lation network based on psychrometric recordings and the use of ResNet, an appro- priate software package. The actual aerodynamic resistance of mine workings are established and consequently, the configuration of the basic network. In this process CFD software can be used in ...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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Optimisation of underground mine decline development system using genetic algorithm
... different decline sections. Access infrastructure designing can be treated as spanning the spatial network which will connect all main terminals (points). In our model we defined spatial network by adequate nonlinear constrained objective function representing the cost of mine development and ore ...
... from each orebody to the surface portal is fixed. A decline development system is modeled as a 3–dimensional or space network interconnecting all main points. Such network must incorporate the navigability constraints caused by the mine trucks and other equipment characteristics. The absolute ...
... case when the deposit is composed of few ore bodies. Underground mine development system is treated as spatial network connecting all main terminals with minimum cost. Such network is defined by adequate objective function. Optimisation model is based on the minimisation of the nonlinear constrained ...Zoran Gligorić, Aleksandar Ganić, Rade Tokalić, Aleksandar Milutinović. "Optimisation of underground mine decline development system using genetic algorithm" in Underground mining engineering, Beograd : Univerzitet u Beogradu – Rudarsko–geološki fakultet (2014)
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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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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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GNSS Time Series as a Tool for Seismic Activity Analysis Related to Infrastructure Utilities
Sanja Tucikešić, Ankica Milinković, Branko Božić, Ivana Vasiljević, Mladen Slijepčević . "GNSS Time Series as a Tool for Seismic Activity Analysis Related to Infrastructure Utilities" in Contributions to International Conferences on Engineering Surveying. Springer Proceedings in Earth and Environmental Sciences, Dubrovnik, Croatia, October 22-23, 2020, Springer, Cham (2021). https://doi.org/10.1007/978-3-030-51953-7_21
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Advantages and challenges in presenting mathematical content using EDX platform
... Online Open Courses (MOOCs). Among MOOCs we can distinguish cMOOCs, which are decentralised, network- based, with non-linear structure, and xMOOCs, where courses are hyper-centralised, content-based, linear, and followed by automated, multiple-choice testing of learners’ understanding of the content ...
... course material, which is in line with the didactic principle of systematization and gradualism in the teaching process. Didactical principle of awareness within the teaching process is represented through the tasks, where activity of users and some kind of interaction between users and platform ...
... for entry exam” is aimed at presenting course materials to help freshmen prepare for entrance exam. In this paper advantages and challenges in the process of creating such a course will be discussed. Special attention will be paid to presenting mathematical content within open educational platforms ...Marija Radojičić, Ivan Obradović, Ranka Stanković, Olivera Kitanović, Roberto Linzalone. "Advantages and challenges in presenting mathematical content using EDX platform" in The Seventh International Conference on e-Learning (eLearning-2016), Belgrade : Metropolitan University (2016)
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Advantages and Disadvantages of a Parallel and Zigzag Method of Acquisition in Walking Mode in Magnetometric Archeological Research
магнетометријска испитивања, цик-цак и паралелна аквизиција у ходајућем моду, линеарне аномалије, археологија... adjacent traverses, it can be concluded that the linear interpolation method leads to the linear anomalies along the direction of acquisition. A decorrugation process using a low-pass moving average fi lter was applied to the data in- terpolated by the linear Kriging method (Figure 8.), in the direction ...
... worn by one operator, linear anomalies were observed in the direction of acquisitions that blur or fl eck other anomolies on the map and can lead to misinter- pretation (Figure 3.a.). To eliminate this anomaly, a low-pass linear moving average decorrugation fi ltering process was applied to the data ...
... same data was gridded using a nonlinear local polynomial method, and it was observed that there was an absence of linear anomalies, which supports the hypothesis that the process of linear interpolation causes anomalies along the travers- es where the acquisition was performed (Figure 10.b.). Archaeology ...Mirko Petković, Vesna Cvetkov, Branislav Sretenović. "Advantages and Disadvantages of a Parallel and Zigzag Method of Acquisition in Walking Mode in Magnetometric Archeological Research" in Arheologija i prirodne nauke (2014)
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Mine ventilation system planning using genetic algorithms
The most common problem in contemporary mining practice related to the planning and analysis of ventilation systems is the optimization of partially regulated air distribution in mine ventilation networks. This paper presents a two step optimization procedure for partly regulated air distribution in mine ventilation networks. The first step is the determination of air distribution in all branches using the well known Hardy-Cross method. In the second step the distribution and parameters of air flow regulators with minimum engaged ...coal, lignite, and peat; ventilation systems; coal mining; underground mining; ventilation; mathematical models; design; air flow; optimization; calculation methodsNikola Lilić, Ranka Stanković, Ivan Obradović. "Mine ventilation system planning using genetic algorithms" in 6. international symposium on mine planning and equipment selection, Ostrava (Czech Republic), 3-6 Sep 1997, A.A. Balkema, Rotterdam (Netherlands) (1997)
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Increasing the Local Road Network Resilience from Natural Hazards in Municipalities in Serbia
Biljana Abolmasov, Miloš Marjanović, Ranka Stanković, Uroš Đurić, Nikola Vulović. "Increasing the Local Road Network Resilience from Natural Hazards in Municipalities in Serbia" in Progress in Landslide Research and Technology, Volume 3, Issue 1, Springer Cham. (2024). https://doi.org/https://doi.org/10.1007/978-3-031-55120-8_22
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An intelligent hybrid system for surface coal mine safety analysis
Nikola Lilić, Ivan Obradović, Aleksandar Cvjetić. "An intelligent hybrid system for surface coal mine safety analysis" in Engineering Applications of Artificial Intelligence (2010)
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Application of Project Management Process on Environmental Management System Improvement in Mining-Energy Complexes
... (450 mg·m2·day), in Drmno (a settlement in the immediate vicinity) emission limit values (ELVs). 3. Project Management Process for Improving Environmental Protection by Applying a Network Planning Technique The management of a mining and energy complex has a duty to promote the environmental protection ...
... patterns are basic conditions for the application of sustainable development principles in the process of improving the environmental protection management system. Figure 8. Illustrative part of the network plan of the branched project structure to improve the environmental protection system in mining ...
... patterns are basic conditions for the application of sustainable development principles in the process of improving the environmental protection management system. Figure 8. Illustrative part of the network plan of the branched project structure to improve the environmental protection system in mining ...Jelena Malenović Nikolić, Dejan Vasović , Ivana Filipović , Stevan Mušicki, Ivica Ristović . "Application of Project Management Process on Environmental Management System Improvement in Mining-Energy Complexes" in Energies (2016). https://doi.org/https://doi.org/10.3390/en9121071
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Gate Road Support Deformation Forecasting Based on Multivariate Singular Spectrum Analysis and Fuzzy Time Series
Luka Crnogorac, Rade Tokalić, Zoran Gligorić, Aleksandar Milutinović, Suzana Lutovac, Aleksandar Ganić (2021)Underground mining engineers and planners in our country are faced with extremely difficult working conditions and a continuous shortage of money. Production disruptions are frequent and can sometimes last more than a week. During this time, gate road support is additionally exposed to rock stress and the result is its progressive deformation and the loss of functionality of gate roads. In such an environment, it is necessary to develop a low-cost methodology to maintain a gate road support system. ...deformacije podgrade, lasersko skeniranje, višekanalna singularna spektralna analiza, prognoza, klasterisanje fuzzy vremenskih serija... types of information was done [1]. Danial Jahed Armaghani et al. [2] applied three-nonlinear forecasting methods, namely a non-linear multiple regression, an artificial neural network, and an adaptive neuro-fuzzy inference system, in order to estimate the uniaxial compressive strength of rock. Grey system ...
... considering the non-linear parameters of the deformation of the tunnel. Ping Tang [4] forecasted the working face underground pressure by applying a grey system theory and genetic algorithm. Sun Yu et al. [5] proposed a time series prediction model based on a generalized regression neural network to predict the ...
... Outliers are values that are either abnormally high or abnormally low in the sorted dataset. The process of elimination of outliers is performed as follows: d− σd ≤ d ≤ d + σd, (17) Since the process of elimination is completed, a revised average distance value dR is calculated for the remaining values ...Luka Crnogorac, Rade Tokalić, Zoran Gligorić, Aleksandar Milutinović, Suzana Lutovac, Aleksandar Ganić. "Gate Road Support Deformation Forecasting Based on Multivariate Singular Spectrum Analysis and Fuzzy Time Series" in Energies, MDPI (2021). https://doi.org/https://doi.org/10.3390/en14123710
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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... (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” by changing adaptable ...
... flow quantities INVENTS ResNet SimVent VENTEX defining basic network resistance ventilation system estimation ventilation simulation Design CFD Estimates estimation of gas and dust emission and temperature conditions flow process modelling using CFD Data acquisition ventilation and psychrometric ...
... select the initial state for the network in such a way that it is much closer to the global minimum thus avoiding possible local minima problems [4]. We have used two approaches in PollutNet for training the NN. The first was the classical one, in which the network weights were adapted by the back ...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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Control of substructure construction of railways in the Republic of Serbia
Контрола збијености природног тла (у ископу) или збијеног у насипу при изградњи саобраћајница представља један од основних облика контроле квалитета доњег строја. Код изградње брзих саобраћајница (аутопутеви и брза железница) приоритет је постизање високог нивоа контроле извршених радова. У циљу онемогућавања диференцијалног слегања (при изградњи насипа), или промене запремине услед допунског збијања материјала, које неминовно доводе до деформација, потребно је извршити оптимално збијање материјала. У оквиру овог рада приказује се техничка регулатива која регулише контролу збијености при изградњи железничке ...... testing process with a clear procedure that includes compliance with existing regulations. LITERATURE [1] Instructions 338 were adopted for the control of compaction of the substrate of railway tracks by the dynamic method with a device with a light falling weight on the JŽ railway network, Official ...
... greater. In order to speed up the testing process, the authors of this paper propose the following methodology: determine profiles for testing according to the standard and technical conditions (harmonized with the standard) determine in examination process the zone where soil homogeneity is ensured ...
... 10% (Casagrande's criterion). For the intermediate values of the coefficient U, the grain content of fractions smaller than 0.02 mm is determined by linear interpolation [2:38-38]. The material in the transition layer should meet the filter criteria in relation to the underlying layer or to be protected ...Dragan Lukić, Dragoslav Rakić, Irena Basarić Ikodinović. "Control of substructure construction of railways in the Republic of Serbia" in International Conference On Contemporary Theory and Practice in Construction XV, Banja Luka 16-17 jun 2022., University of Banja Luka Faculty of Architecture, Civil Engineering and Geodesy (2022)
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Atmospheric exposure vs burying: influences on damage intensity of built-in kersantite in the monument of the Small Staircase (Belgrade, Serbia)
Proučavan je efekat „zatrpanog kamena“ na intenzitet procesa degradacije prisutnih na kersantitu koji je ugrađen u spomenik Malo stepenište. Istraživanja su vršena na uzorcima stene iz kamenoloma i na oštećenim kamenim blokovima ugrađenim u spomenik. Dok su neki delovi stepeništa bili pod zemljom 90 godina, većina kamenih elemenata je bila izložena različitim uslovima sredine i antropogenim uticajima. Urađeno je detaljno mapiranje trenutnog stanja spomenika kako bi se istražio uticaj “zatrpavanja” i kompleksne geometrije spomenika na tip propadanja i variranje ...Nevenka Novaković, Predrag Dabić, Vesna Matović. "Atmospheric exposure vs burying: influences on damage intensity of built-in kersantite in the monument of the Small Staircase (Belgrade, Serbia)" in Environmental Earth Sciences, Springer Science and Business Media LLC (2023). https://doi.org/10.1007/s12665-023-10794-6