Претрага
584 items
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Development and Application of Methodology for Quantification of Overbreaks in Hard Rock Tunnel Construction
A methodology for determining overbreaks in hard rock tunnel construction using the drill-and-blast technique is presented in this paper. The methodology was developed for and applied to crystalline medium- to thick-bedded limestone, but it can be used in any jointed hard rock mass. Overbreaks are inevitable in hard rock tunnelling in a low-confinement environment (shallow tunnels up to several hundred meters deep) as a result of wedge failures along unfavourably oriented discontinuities caused by blasting. It is widely accepted ...hard rock, drill-and-blast, geological overbreak, technological overbreak, stability criterion, discontinuity orientation, tunnel constructionZoran Berisavljević, Dragoljub Bajić, Vojkan Jovičić. "Development and Application of Methodology for Quantification of Overbreaks in Hard Rock Tunnel Construction" in Applied Sciences, MDPI (2023). https://doi.org/10.3390/app13031379
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Numerical modeling of Selanac debris flow propagation using SPH code
The Selanac debris flow is a very huge event triggered after extreme rainfall caused by Cyclone Tamara activity in the Republic of Serbia in May 2014. The Selanac case study was already modelling in different programs using Voellmy rheology assumptions like RAMMS software. In this paper research are focusing particularly on the process of debris flowing from initiation zone to main deposition area using Geoflow SPH two-phase model considering frictional rheology law. Main rheological parameters are back-calculated using also ...... with either water or mud. If the shear resistance of the fluid phase can be neglected, the stress tensor in the mixture can be decomposed into a ‘pore pressure’ and an effective stress, and the mechanical behavior of the mixture can be described by a system of differential equations governing the ...
... (Zienkiewicz and Schiomi, 1984) and it can be used with a variety of rheological laws and pore water pressure treatments. Two different meshes will be used, one to describe the terrain topography while the other consist of SPH nodes. Detailed discretization of equations can be found in Pastor et al. (2009) ...
... effect it can be concluded that the simulation model is capable to obtain reasonable results and properly back-calculate the deposition depth and runout distance. However, Selanačka river had a significant influence on process which was not considered in the simulation models. It can be supposed ...Jelka Krušić, Biljana Abolmasov, Miloš Marjanović, Manuel Pastor, Saeid M. Tayyebi . "Numerical modeling of Selanac debris flow propagation using SPH code" in SCG-XIII International Symposium on Landslides. Cartagena, Colombia- February 22-26, 2021, International Society for Soil Mechanics And Geotechnical Engineering (2021)
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Preliminary regional landslide susceptibility assessment using limited data
Igor Peshevski, Milorad Jovanovski, Biljana Abolmasov, Jovan Papic, Uroš Đurić, Miloš Marjanović, Ubydul Haque, Natasha Nedelkovska (2019)In this paper a heuristic approach for preliminary regional landslide susceptibility assessment using limited amount of data is presented. It is called arbitrary polynomial method and takes into account 5 landslide conditioning parameters: lithology, slope inclination, average annual rainfall, land use and maximum expected seismic intensity. According to the method, in the first stage, a gradation is performed for each of the carefully selected conditioning parameters by assigning so called rating points to the grid cells on which the ...... noted once again that, even methods such as those presented in this paper can be used only as a first estima- tion of landslide susceptibility, and one can argue that they are based mostly on engineering judgment. They can however pro- vide indications of the aspects that deserve attention while allow- ...
... map of landslides of a particular region, the validation process can then be conducted. In order to investigate the sensitivity of the basic landslide susceptibility models (TLSR models) obtained, each conditional parameter rating can be additionally weighted by so called sen- sitivity coefficients ...
... of ratings and sensitivity coefficients. It can be ar- gued that this approach translates the susceptibility analysis into a trial and error exercise, making it highly subjective. However, with careful analysis of all the available data, weightings can be reasonably well selected, which will ultimately ...Igor Peshevski, Milorad Jovanovski, Biljana Abolmasov, Jovan Papic, Uroš Đurić, Miloš Marjanović, Ubydul Haque, Natasha Nedelkovska. "Preliminary regional landslide susceptibility assessment using limited data" in Geologica Croatica , Croatian Geological Society (2019). https://doi.org/10.4154/gc.2019.03
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Threshold-induced correlations in the Random Field Ising Model
... waiting time Tw,0 increases with Vth. �is is shown in the bottom inset of Fig. 2a, where one can see that the relation ∼ δT Vw,0 th is satis�ed with δ ≈ 1.30 ± 0.02. Regarding the shape of distributions D(Tw), one can see that the power law part appears with the increase of threshold, indicating the onset ...
... waiting time T,,o increases with V,,. This is shown in the bottom inset of Fig. 2a, where one can see that the relation T,, . ~ ‘is satisfied with 6~ 1.30 + 0.02. Regarding the shape of distributions D(T,,), one can see that the power law part appears with the increase of threshold, indicating the onset ...
... 0. Essentially the same can be said for discrete signals sampled at discrete moments of time, provided that they are continuously (e.g. linearly) extrapolated to all moments of time throughout the signal duration, like it is done here with the RFIM signals. �e avalanches can be classi�ed into types ...Sanja Janićević, Dragutin Jovković, Lasse Laurson, Đorđe Spasojević. "Threshold-induced correlations in the Random Field Ising Model" in Scientific Reports, Springer Science and Business Media LLC (2018). https://doi.org/10.1038/s41598-018-20759-6
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Electronic Dictionaries - from File System to lemon Based Lexical Database
In this paper we discuss some well-known morphological descriptions used in various projects and applications (most notably MULTEXT-East and Unitex) and illustrate the encountered problems on Serbian. We have spotted four groups of problems: the lack of a value for an existing category, the lack of a category, the interdependence of values and categories lacking some description, and the lack of a support for some types of categories. At the same time, various descriptions often describe exactly the same ...... so that the dictionary of forms containing all nec- essary grammatical information can be generated from it, and subsequently used in various NLP tasks (Courtois and Silberztein, 1990). A dictionary of lemmas can con- tain simple-word lemmas (DELAS) or multi-word lemmas (DELACF), producing, respectively ...
... attribute can belong to a closed set (e.g. +CC2=RS is a two character coun- try code marker assigned, for instance, to geopolitical names), or to an open set (e.g. +Val=Vaughn is as- signed to a surname Von, Serbian transcription of the English surname Vaughn). Semantically, markers can be of various ...
... indicates that the suf- fix -rati can be substituted in the lemma afirmirati by the suffix -sati to produce the lemma afirmisati, which is recorded in e-dictionaries and has an inverse marker +VAR=SatiRati assigned to it. The marker +VAR=H0 indicates that an h can be deleted in the lemma hleb to ...Ranka Stanković, Cvetana Krstev, Biljana Lazić, Mihailo Škorić. "Electronic Dictionaries - from File System to lemon Based Lexical Database" in Proceedings of the 11th International Conference on Language Resources and Evaluation - W23 6th Workshop on Linked Data in Linguistics : Towards Linguistic Data Science (LDL-2018), LREC 2018, Miyazaki, Japan, May 7-12, 2018, European Language Resources Association (ELRA) (2018)
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Analysis Of the Process Of Carbon Capture Utilization And Storage In Underground Reservoirs
John Nyame (2024)The importance of mitigating the effects of global climate change has necessitated an in-depth exploration of innovative strategies to reduce carbon dioxide (CO2) emissions. Among these strategies, Carbon Capture, Utilization, and Storage (CCUS) has emerged as a promising and transformative solution. This master thesis delves into the diverse realm of CCUS processes, aiming to unravel the positives challenges, and opportunities within this dynamic field. The analysis begins with a systematic examination of carbon capture technologies, encompassing post-combustion, pre-combustion, and oxy-fuel combustion ...... removal of the ions from the water phase. The products sodium bicarbonate and ammonium chloride are heavy and, thus, can easily settle to the bottom of the tank. The latter NH4CI can be recycled by thermal operations with calcium oxide or be used as a feedstock for the synthesis of ammonia and chlorine ...
... the best route in CO» utilization. Methane, methanol, syngas, and alkanes are some of the compounds that can be produced by utilizing captured CO» as a feedstock [13]. The fuel produced can be used in various sectors, including fuel cells, power plants, and transportation. CO> conversion requires ...
... placement of CO» in underground formations. Potential storage formations can occur in onshore and offshore formations, and each type of geologic formation presents different risks and rewards. CO» accumulation naturally can be found in geological sites round the world, mostly in sedimentary basins ...John Nyame. Analysis Of the Process Of Carbon Capture Utilization And Storage In Underground Reservoirs, 2024
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SASA Dictionary as the Gold Standard for Good Dictionary Examples for Serbian
Ranka Stanković, Branislava Šandrih, Rada Stijović, Cvetana Krstev, Duško Vitas, Aleksandra Marković (2019)У овом раду представљамо модел за избор добрих примера за речник српског језика и развој иницијалних компоненти модела. Метода која се користи заснива се на детаљној анализи различитих лексичких и синтактичких карактеристика у корпусу састављених од примера из пет дигитализованих свезака речника САНУ. Почетни скуп функција био је инспирисан сличним приступом и за друге језике. Дистрибуција карактеристика примера из овог корпуса упоређује се са карактеристиком дистрибуције узорака реченица ексцерпираних из корпуса који садрже различите текстове. Анализа је показала да ...Српски, добри примери из речника, аутоматизација израде речника, издвајање својстава, Машинско учење... examples derived from the SASA dictionary is a dataset of good dictionary examples that can serve various purposes: it can be used to procure examples for the SASA dictionary as well as for new dictionaries, but it can also be used for the development of a machine system for example selection. From ...
... From the analysis of samples of dictionary examples, metrics and example feature distribution can be derived, which can reduce the search space for relevant examples, for example, by setting the upper and lower limits for sentence length, based on the 251 Proceedings of eLex 2019 most common ...
... advisable to use more than one example of the same author. An exception to this rule can be made if there are not enough examples by other authors. Only a few linguistic criteria are mentioned in the Style Guide. They can be paraphrased as follows: 1) each chosen example should show different relations ...Ranka Stanković, Branislava Šandrih, Rada Stijović, Cvetana Krstev, Duško Vitas, Aleksandra Marković. "SASA Dictionary as the Gold Standard for Good Dictionary Examples for Serbian" in Electronic lexicography in the 21st century. Proceedings of the eLex 2019 conference , Lexical Computing CZ, s.r.o. (2019)
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The number of unimodular roots of some reciprocal polynomials
Dragan Stankov (2020)We introduce a sequence P2n of monic reciprocal polynomials with integer coefficients having the central coefficients fixed. We prove that the ratio between number of nonunimodular roots of P2n and its degree d has a limit when d tends to infinity. We present an algorithm for calculation the limit and a numerical method for its approximation. If P2n is the sum of a fixed number of monomials we determine the central coefficients such that the ratio has the minimal limit. ...Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomialsDragan Stankov. "The number of unimodular roots of some reciprocal polynomials" in Cmptes rendus mathematique (2020). https://doi.org/10.5802/crmath.28
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Production information system of the Pljevlja coal mine
Božo Kolonja, Ranka Stanković, Filip Vuković . "Production information system of the Pljevlja coal mine" in Mine Planning and Equipment Selection 2000, Routledge (2018). https://doi.org/10.1201/9780203747124-154
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Mio-Pliocene Geodynamics and its Stratigraphic Consequences in the Area of Avala Mt. (Belgrade, Serbia)
... estimated as 11.4–14.2 cm/kyr for the Taman Konkian. °e duration of the Konkian can be estimated as 0.2–0.25 Myr without taking into account the sedimentation rate for the carbonate layers. Based on the obtained results we can suggest that the change from normal to reversed polar- ity in the lower part ...
... estimated as 11.4-14.2 cm/kyr for the Taman Konkian. The duration of the Konkian can be estimated as 0.2-0.25 Myr without taking into account the sedimentation rate for the carbonate layers. Based on the obtained results we can suggest that the change from normal to reversed polar- ity in the lower part ...
... Eastern Paratethys Konkian (MOLOSTOVSKY & CHRAMOV, 1997; GREBENYUK, 2004) relates to the Chron C5AAn/C5Ar.3r boundary. °e duration of the Kon- kian can be estimated as 0.35–0.45 Myr. °is work was ºnancially supported by the RFBR (№17-05-01085, №16-05-01032) and RSF (№17-17-01146). GREBENYUK, L.V. ...Ljupko Rundić, Meri Ganić, Slobodan Knežević, Dejan Radivojević. "Mio-Pliocene Geodynamics and its Stratigraphic Consequences in the Area of Avala Mt. (Belgrade, Serbia)" in 7th International Workshop: Neogene of Central and South-Eastern Europe, Velika, Croatia, maj 2017, Croatian Geological Society (2017)
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Korelacija magnetnog susceptibiliteta i sadržaja metala u flotacijskom jalovištu
Procena metala u rudama, jalovištu i zemljištu se tradicionalno određuje hemijskim metodama kao što su Rengen fluorescentna analiza (XRF), Instrumentalna neutronska aktivaciona analiza (INAA) i Masena spektrometrija induktivno spregnute plazme (ICP-MS). Neke od pomenutih metoda su veoma zahtevne i skupe, te se nametnula potreba ka traženju jeftinijeg alata za brzu procenu prisustva pojedinih metala. Tokom poslednjih nekoliko decenija, mnoge studije su pokazale da su magnetna merenja dovoljno osetljiva da detektuju magnetni signal feromagnetnih materijala, a samim tim i metala ...Filip Abramović, Vesna Cvetkov, Aco Ilić, Dragana Životić. "Korelacija magnetnog susceptibiliteta i sadržaja metala u flotacijskom jalovištu" in 18. Kongres geologa Srbije "Geologija rešava probleme", Divčibare, 01-04 jun 2022., Srpsko geološko društvo (2022)
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Linearization of Input Signal as a Necessary Tool in Stochastic Modeling of Karst Groundwater
Veljko Marinović (2021)Modelling of karst hydrogeological systems is a very complicated task, bearing in mind that for a deterministic model one should know the internal physical processes of precipitation transformation into discharge, while for a stochastic model nonlinear dynamic systems such as karst should be simulated by linear regression equations. Stochastic models need linearization of input time series due to often large residual in the recession period. This occur because the model is not able to absorb single rain episodes, which ...Veljko Marinović. "Linearization of Input Signal as a Necessary Tool in Stochastic Modeling of Karst Groundwater" in Karst: From Top to Bottom, Belgrade, 6.6.2021., Belgrade : Centre for Karst Hydrogeology (2021)
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The impact of temporal variability of groundwater levels on groundwater vulnerability maps in karst terrains – a case example of the Perućac spring catchment area
Groundwater vulnerability maps represent an essential tool for protecting karst groundwater resources. Vulnerability assessment is usually based on spatial evaluation of various parameters that affect the vulnerability degree and regulate the protection role of the unsaturated zone. Most of these parameters, like soil and geology conditions, are constant and do not change during the year or over several years. In contrast, some parameters, such as the groundwater level, depend on the variability of recharge conditions. By considering the variability ...Vladimir Živanović, Igor Jemcov, Nebojša Atanacković. "The impact of temporal variability of groundwater levels on groundwater vulnerability maps in karst terrains – a case example of the Perućac spring catchment area" in 5th IAH CEG conference, Slovenian Committee of International Association of Hydrogeologists - SKIAH (2022)
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Development of the hybrid MCDM model for evaluating and selecting bucket wheel excavators for the modernization process
This paper presents a methodology for evaluating and ranking different bucket wheel excavators (BWE) for determining which machine should enter in the process of revitalization and modernization. Various multicriteria methods are used. Combining them achieves the best effect when choosing BVE for the modernization process. AHP, TOPSIS, VIKOR, and PROMETHEE methods are used. The hybrid models are developed from the multi-criteria decision making (MCDM) methods and they are used to evaluate the basic indicators that characterize the operation of ...Snezana Savkovic, Predrag Jovancic, Stevan Djenadic, Milos Tanasijevic, Filip Miletic. "Development of the hybrid MCDM model for evaluating and selecting bucket wheel excavators for the modernization process" in Expert Systems with Applications, Elsevier BV (2022). https://doi.org/10.1016/j.eswa.2022.117199
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A Twitter Corpus and Lexicon for Abusive Speech Detection in Serbian
Uvredljivi govor na društvenim medijima, uključujući psovke, pogrdni govor i govor mržnje, dostigao je nivo pandemije. Sistem koji bi bio u stanju da detektuje takve tekstove mogao bi da pomogne da internet i društveni mediji postanu bolji virtuelni prostor sa više poštovanja. Istraživanja i komercijalna primena u ovoj oblasti do sada su bili fokusirani uglavnom na engleski jezik. Ovaj rad predstavlja rad na izgradnji AbCoSER-a, prvog korpusa uvredljivog govora na srpskom jeziku. Korpus se sastoji od 6.436 ručno označenih ...... classification can be done in several steps. Traditional machine learning can also be used at every step, which in the case of a smaller number of class examples gives better results than deep learning [31]. Another advantage is a simpler structure of the annotation decision tree, which can contribute to ...
... collect examples of online hate speech in all languages that can be used as trigger words for hate speech detection ([46, 41, 14, 13]). However, detecting hate speech by simply filtering by keywords is not a satisfactory solution, as interpretation can be influenced by the domain of the conversation, the context ...
... prepared the guidelines for annotators in the same format (shown in Figure 2). One can see from the decision tree that a tweet marked as abusive has to be tested for each subcategory, since, as mentioned earlier, one tweet can belong to one or more subcategories. Annotators had a tab in their annotation interface ...Danka Jokić, Ranka Stanković, Cvetana Krstev, Branislava Šandrih. "A Twitter Corpus and Lexicon for Abusive Speech Detection in Serbian" in 3rd Conference on Language, Data and Knowledge (LDK 2021), MDPI AG (2021). https://doi.org/10.4230/OASIcs.LDK.2021.13
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Development of Open Educational Resources (OER) for Natural Language Processing
In this paper we present the development of an online course at the edX BAEKTEL platform named “Lexical Recognition in the Natural Language Processing (NLP)”. It is based on the course of the same name for PhD studies at the University of Belgrade, Faculty of Philology. There are not many courses in Computational Linguistics (CL) on OER platforms, and there is none in Serbian either for CL or NLP. We have developed this course in order to improve this ...... more. For text processing simple string operations can be used, but underlying e- dictionaries enable much more sophisticated approaches. Besides simple regular expressions, graphs that represent the visualization of finite state automata (FSA) can be used for complex queries. Moreover, finite state ...
... output) can be used for text transformation. The concept of e-dictionaries and software that enables their effective use was developed at LADL (Laboratoire d' Automatique Documentaire et Linguistique), under the direction of its director, Maurice Gross. [12] With Unitex, user can develop ...
... (CL) on OER platforms, and there is none in Serbian either for CL or NLP. We have developed this course in order to improve this situation as it can prove useful both for linguists working in corpus linguistics and computer scientists developing NLP applications. The participant will become familiar ...Cvetana Krstev, Biljana Lazić, Ranka Stanković, Giovanni Schiuma, Miladin Kotorčević. "Development of Open Educational Resources (OER) for Natural Language Processing" in The Sixth International Conference on e-Learning (eLearning-2015), September 2015, Belgrade, Serbia, Belgrade : Belgrade Metropolitan Univesity (2015)
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Pre-failure deformation monitoring as rockfall prediction tool
... should be, and data are usually scarce. Modeling and simulation is another tool that can be used to estimate some of the rockfall parameters and compensate for the lack of specific data [1]. Suspicious rock faces can be monitored for longer periods, using multiple monitoring systems (primarily Terrestrial ...
... research is that TLS successfully captures cm displacements and can be used to anticipate the future events. In addition, mm displacements, are more oscillating in respect to temperature and other atmospheric agents, meaning that TLS can be fully used to monitor significant events. Using all these ...
... all exhibited displacements can be observed in X axis, instead of using total vectors. Thus, the threshold displacement is not the total vector but its X component, which is more practical for systematic application of the approach. If applied systematically, it can provide excellent information ...Miloš Marjanović, Biljana Abolmasov, Zoran Berisavljević, Marko Pejić, Petko Vranić. "Pre-failure deformation monitoring as rockfall prediction tool" in IOP Conference Series: Earth and Environmental Science, IOP Publishing (2021). https://doi.org/10.1088/1755-1315/833/1/012197
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Conversion of land areas after coal mine closure and reclamation
Otkopavanje uglja površinski i podzemno praćeno je degradacijom zemljišta, promenom formiranja predela i izmenom flore i faune. Od velikog značaja je razvoj novih naučno utemeljenih pristupa obnovljanje antropogeno poremećenih predela zasnovanih na formiranju rekultivacionih i rudarskih tehnologija. Apsolutno je neophodno obezbediti sveobuhvatno kvalitetno očuvanje zemljišnih i vodnih resursa i odrediti rekultivisano zemljište za novu namenu. U ovom članku je dat pregled najpopularnijih metoda rekultivacije zemljišta i mogućnosti rekultivacije zemljišta nakon završetka rekultivacije i zatvaranja rudnika uglja.... the surface mine. 254 Table 1 shows comparison of the methods that can be applied to select the purpose of the terrain after reclamation, their feature, advantages and disadvantages. Table 1. Comparison of methods which can be used for choosing a recultivation solution Method Feature Advantage ...
... The development characteristics of rehabilitated vegetation at different land reclamation stages are significantly different, and these differences can be used to identify the key stages of land reclamation [3]. Land reclamation plays a vital role in the ecological improvement and economic development ...
... assessing: and mapping the environmental data concerning coal mining activities is still missing in contrast to the sociO-economic concern. The same can be applied to the quality land reclamation and follow-up use of reclaimed land. Even though there is considerable progress in recultivation practices ...Radmila Gaćina, Bojan Dimitrijević, Sanja Bajić. "Conversion of land areas after coal mine closure and reclamation" in 9th International conference mining and environmental protection MEP 23 Proceedings, Sokobanja, 24-27.05.2023., Belgrade : University of Belgrade - Faculty of mining and geology (2023)
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Quantitative analysis of syllable properties in Croatian, Serbian, Russian, and Ukrainian
Biljana Rujević, Marija Kaplar, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Jan Mačutek (2021)Biljana Rujević, Marija Kaplar, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Jan Mačutek. "Quantitative analysis of syllable properties in Croatian, Serbian, Russian, and Ukrainian" in Language and Text: Data, models, information and applications, John Benjamins Publishing Company (2021). https://doi.org/10.1075/cilt.356.04ruj
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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... global minimum. This shortcoming of back propagation NN can be eliminated by coupling it with another AI method such as the genetic algorithms (GA). Namely, GA may be very helpful in approaching the global minimum, where the neural network can take over and proceed until it reaches the minimum itself ...
... is randomly selected, and therefore can be far from the global minimum. Having this in mind we decided to couple the NN with GA in PollutNet to overcome this possible shortcoming, which makes PollutNet itself a function-replacing hybrid system. Namely, GA can be used to select the initial state for ...
... 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 ...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)