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Упит dcterms_subject_txt:economical evaluation

354 items

  • Application of the Fuzzy Model in the Evaluation and Selection of Hydraulic Excavators on Open-Pit Lignite Mine

    Stevan Đenadić, Miloš Tanasijević, Vladimir Milisavljević, Dragan Ignjatović, Predrag Jovančić (2021)
    The production of lignite in large open-pit mines is mainly performed with continuously operating equipment, where bucket-wheel excavators, bucket-chain excavators, belt conveyors, and spreaders are the basic machines. Smaller machines, usually of discontinuous operating nature, are commonly categorized as auxiliary machines. This paper presents the research related to the analysis of auxiliary machine parameters with the case study for a hydraulic excavator. The purpose of the analysis was to develop a model of rating quality of service of the ...
    Fuzzy theory, hydraulic excavator, selection, quality of service, asset management

  • Razvoj algoritma fuzzy optimizacije u hidrodinamičkoj analizi za potrebe projektovanja sistema odbrane od podzemnih voda

    Dragoljub Bajić, Dušan Polomčić (2019)
    Sistemi za odbranu od podzemnih voda se koriste za zaštitu hidrotehničkih objekata, priobalja, meliorativnih područja, naselja, rudnika, industrijskih područja, predstavljajući značajne segmente bez kojih bi funkcionalnost ovih objekata i područja bila dovedena u pitanje. Posebno složeni sistemi odbrane od podzemnih voda se karakterišu kod ležišta mineralnih sirovina, imajući u vidu njihovu dinamičnost, koja se ogleda u stalnom širenju ležišta, kao i činjenicu da ova ležišta prodiru duboko u stensku masu različitog strukturnog tipa poroznosti, a time i u podzemne ...
    upravljanje podzemnim vodama, hidrodinamički model, fuzzy logika, trougaoni fuzzy brojevi, znanje eksperta, optimizacija

  • A Model for Determining the Dependability of Continuous Subsystems in Coal Mines Using the Fuzzy Logic Approach

    Nikola Stanić, Miljan Gomilanović, Petar Marković, Daniel Krzanović, Aleksandar Doderović, Saša Stepanović (2024)
    This study presents a unique model for assessing the dependability of continuous parts of combined systems in open-pit mining through the application of fuzzy logic. Continuous sub-systems as part of the combined system of coal exploitation in surface mines have the basic function of ensuring safe operation, high capacity with high reliability, and low costs. These subsystems are usually part of the thermal power plant’s coal supply system and ensure stable fuel supply. The model integrates various independent partial ...
    fuzzy logic, max-min composition, continuous part of combined system (CCS), open pit, mining, dependability

  • Uticaj voda Dunava na formiranje kvaliteta podzemnih voda u zoni Apatina

    Bojan Hajdin, Željko Kljajić, Vesna Ristić-Vakanjac, Milojko Lazić, Marina Čokorilo-Ilić (2018)
    Područje Apatina u proteklom periodu često je pominjano u razvojnim vodoprivrednim strategijama kao potencijalno perspektivna lokacija za izgradnju izvorišta duž obale Dunava, koje bi moglo da ima regionalni značaj. Ovim rešenjem trebao bi se prevazići problem lošeg kvaliteta vode za piće na celom području severne Bačke, tako što bi se kvalitet podzemne vode poboljšao zahvatanjem infiltriranih rečnih voda u priobalju Dunava. Istraživanjima koja je Departman za hidrogeologiju, Rudarsko-geo¬loškog fakulteta vršio tokom poslednjih 13 godina na izvorištima za vodosnabdevanje grada ...
    vodosnabdevanje, osnovni vodonosni kompleks Vojvodine, regionalni vodovodni sistem

  • Development of the hybrid MCDM model for evaluating and selecting bucket wheel excavators for the modernization process

    Snezana Savkovic, Predrag Jovancic, Stevan Djenadic, Milos Tanasijevic, Filip Miletic (2022)
    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 ...
    višekriterijumsko odlučivanje, rotorni bageri, modernizacija, ekspertska analiza

  • Extraction of Bilingual Terminology Using Graphs, Dictionaries and GIZA++

    Branislava Šandrih, Ranka Stanković (2020)
    U nauci, industriji i mnogim istraživačkim oblastima, terminologija se brzo razvija. Najčešće, jezik koji je „lingua franca“ za većinu ovih oblasti je engleski. Kao posledica toga, za mnoga polja termini domena su koncipirani na engleskom, a kasnije se prevode na druge jezike. U ovom radu predstavljamo pristup za automatsko izdvajanje dvojezične terminologije za englesko-srpski jezički par koji se oslanja na usaglašeni dvojezični korpus domena, ekstraktor terminologije za ciljni jezik i alat za usklađivanje delova. Ispitujemo performanse metode na domenu ...
    ekstrakcija terminologije, validacija terminologije, GIZA++, grafovi, Unitex, klasifikacija teksta
    ... syntactic patterns applying specified op- tions and further processing (lemmatisation, calculation of statistical measures, support for manual evaluation and final evaluation report). For automatic extraction and lemmatisation, the system calls Unitex command-line functions in the background to apply appropriate ...
    ... other MWT extractors were considered for obtaining English MWTs: TextPro3 (Pianta et al., 2008), TermSuite4 (Cram and Daille, 2016) and TermEx2.8.5 Evaluation performed on the list of terms ex- tracted by all four extractors and evaluated as potential MWU terms showed that FlexiTerm outperformed the other ...
    ... applicable only for (LIS-dict) experiments). In order to assess the efficiency of our approach, we have first evaluated all extracted pairs manually. Evaluation results showed that a number of new term pairs were retrieved. When LIS-dict was used as a source of English terminology, 364 English terms from ...

  • Damage quantification of built stone on Dark Gate (Belgrade, Serbia): sample of damage index application for decay rate evaluation

    Maja Franković, Nevenka Novaković, Vesna Matović (2015)
    The Dark Gate is the monument of culture, part of the cultural and historical complex of the Belgrade Fortress. It is constructed of limestone blocks that after 270 years of exposure to environmental conditions and different anthropogenic influences show wide ranges of decay forms. During 2007, detail registration of all built limestone microfacies and weathering forms was done using tools of monument mapping. A correlation scheme ‘‘intensity– damage category’’ was made according to the type, intensity, and distribution of ...
    Krečnjak, mapiranje, Indeks raspadanja, brzina raspadanja, progresija
    ... decay rate evaluation Maja Franković, Nevenka Novaković, Vesna Matović Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Damage quantification of built stone on Dark Gate (Belgrade, Serbia): sample of damage index application for decay rate evaluation | Maja Franković ...
    ... ARTICLE @ CrossMark Damage quantification of built stone on Dark Gate (Belgrade, Serbia): sample of damage index application for decay rate evaluation Maja Franković · Nevenka Novaković · Vesna Matović Received: 16 May 2014/ Accepted: 31 October 2014/ Published online: 4 December 2014 OO ...
    ... and Geochemistry, University of Belgrade, Djusina 7, Belgrade, Serbia e-mail: vesna.matovic('rgf.bg.ac.rs intervention. After 7 years, re-evaluation of these param- eters was done. New data of weathering: mapping and recalculated values of damage indices reflected significant acceleration ...

  • 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
    ... so did capital expendi- ture and operating and maintenance costs. However, it should be noted that in some cases the construction of wells is more economical than the pumping time. Flexibility included the ability of the system to adapt to possible changes to its char- acteristics. Consequently, when the ...
    ... Performan- ce evaluation of international airports in the region of East Asia. Proceedings of the Eastern Asia Society for Transportation Studies, 4: 213–230. CHOU, T.Y. & LIANG, G.S. 2001. Application of a fuzzy multi-criteria decision making model for shipping com- pany performance evaluation. Maritime ...
    ... Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station 109 Table 2. Ultimate evaluation of alternatives. evaluation and fuzzy sets analysis. Water Resource Ma- nagement, 18: 13–33. KOSKO, B. 1993. Fuzzy thinking: The new science of fuzzy logic ...

  • Application of Project Management Process on Environmental Management System Improvement in Mining-Energy Complexes

    Jelena Malenović Nikolić, Dejan Vasović , Ivana Filipović , Stevan Mušicki, Ivica Ristović (2016)
    menadžment, rudrastvo i energetski kompleksi, okruženje, održivi razvoj, mrežno planiranje
    ... areas of land. The previous calculus is grounded on risk management approach, which includes: the model of aspect importance evaluation based on aspect seriousness evaluation, probability of occurrence and quantity, as key elements for defining aspect importance [22]. There are five categories of the ...
    ... areas of land. The previous calculus is grounded on risk management approach, which includes: the model of aspect importance evaluation based on aspect seriousness evaluation, probability of occurrence and quantity, as key elements for defining aspect importance [22]. There are five categories of the ...
    ... impact on human health? A positive answer to any of the questions is graded 1 and a negative 0. Table 4 presents the proposal for defining risk evaluation (R) and determining the importance of proposed environmental aspects (I), according to probability of occurrence, quantity, and seriousness of impact ...

  • An Approach to Efficient Processing of Multi-Word Units

    Cvetana Krstev, Ivan Obradović, Ranka Stanković, Duško Vitas (2013)
    Efficient processing of Multi-Word Units in the course of development of morphological MWU dictionaries is not easy to achieve, especially when languages with complex morphological structures are concerned, such as Serbian. Manual development of this type of dictionaries is a tedious and extremely slow process. To alleviate this problem we turned to our multipurpose software tool, dubbed LeXimir, in the production of lemmas for e-dictionaries of multi-word units. In addition to that, we developed a procedure aimed at making ...
    Natural Language Processing, Grammatical Category, Lexical Representation, MWU, multi-word unit
    ... Efficient Processing of Multi-Word Units 17 4.4 Procedure Evaluation In order to evaluate the performance of LeXimir’s functionality for automated gen- eration of MWU lemmas we have conducted experiments on two occasions. The first evaluation took place in the first phase of the development of our procedure ...
    ... the results obtained in the first evaluation would seem natural, it is not easy to 18 Cvetana Krstev, Ivan Obradović, Ranka Stanković, and Duško Vitas draw a conclusion whether we have made a substantial improvement in our strategy from the first evaluation cycle, given the relative heterogeneity ...
    ... out that in the case of relatively comparable sets of geographic names from the first evaluation and proper names from the second, a considerable improvement was reached beyond doubt. In the second evaluation we also looked at the relation between the number of MWU components and the results obtained ...

  • 3D modeling and monitoring of karst system as a base for its evaluation and utilization: a case study from eastern Serbia

    Saša Milanović, Zoran Stevanović, Ljiljana Vasić, Vesna Ristić-Vakanjac (2013)
    Earth-Surface Processes, Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • 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
    ... n of energy sources for 21% by introduction of locally available renewable energy sources. Although outcomes of this research do not include economical parameters, they can serve as a support in assessing investments in different technical options. The obtained results can be useful for investors ...
    ... heat can be evaluated. Fig. 1 Methodology for evaluation of effects of full recoverable wastewater heat energy potential utilization in district heating systems with heat pumps M. Živković, D. Ivezić 1 3 Key performance indicators For the evaluation, comparison and analysis of the current and ...
    ... wastewater treatment plants but with district heating systems. An estimation of the recoverable heat energy potential of wastewater is used for evaluation of some effects that could be obtained through its full utilization for heat production in the existing district heating systems. Three groups of ...

  • Improving Document Retrieval in Large Domain Specific Textual Databases Using Lexical Resources

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2017)
    Large collections of textual documents represent an example of big data that requires the solution of three basic problems: the representation of documents, the representation of information needs and the matching of the two representations. This paper outlines the introduction of document indexing as a possible solution to document representation. Documents within a large textual database developed for geological projects in the Republic of Serbia for many years were indexed using methods developed within digital humanities: bag-of-words and named ...
    ... facet. 4 Evaluation The improved system includes an evaluation module, which allows a logged user to evaluate the relevance of retrieved documents after the search has been com- pleted.5 Figure 5 depicts the evaluation panel: when the query and the search Fig. 5. The web panel for evaluation of retrieved ...
    ... Average Precision graph. In this section we will present and describe these graphs. The goal of evaluation was to assess and compare the efficiency of the initial and improved search methods. The evaluation was performed over the entire col- lection of documents and a set of 55 information needs, represented ...
    ... methods. Fig. 12. Average precision for the query “geothermal energy in spas”. Evaluation results presented here are publicly available.6 According to one of the evaluators the initial system only “looks nice” but its evaluation is cumber- some, and the improved system is by all means more precise. Another ...

  • 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

  • Evaluation of the effects of wastewater heat pump integration into district heating systems by simulation

    Dejan Ivezić, Marija Živković, Dimitrije Manić, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović (2023)
    The integration of wastewater heat pumps (using purified water) in district heating systems is analyzed in this paper. The simulation procedure is proposed to analyze the impacts of stochasticity of purified water temperature and flow to heat pump integration and operation. The analysis includes calculation of the daily and seasonal coefficient of performance, as well as fossil fuel savings and CO2 emission reduction due to wastewater heat pump use. The proposed procedure is implemented for the case study in ...
    otpadne vode, toplotna pumpa, daljinsko grejanje, simulacija

  • Characterization and Environmental Evaluation of Recycled Aggregates from Construction and Demolition Waste in Belgrade City Area (Serbia)

    Filip Abramović, Miroslav Popović, Vladimir Simić, Vesna Matović, Radmila Šerović (2024)
    General Materials Science

  • Keyword-Based Search on Bilingual Digital Libraries

    Ranka Stanković, Cvetana Krstev, Duško Vitas, Nikola Vulović, Olivera Kitanović (2017)
    This paper outlines the main features of Biblisha, a tool that offers various possibilities of enhancing queries submitted to large collections of aligned parallel text residing in bilingual digital library. Biblishsa supports keyword queries as an intuitive way of specifying information needs. The keyword queries initiated, in Serbian or English, can be expanded, both semantically, morphologically and in other language, using different supporting monolingual and bilingual resources. Terminological and lexical resources are of various types, such as wordnets, electronic ...

  • INVENTS: A Hybrid Mine Ventilation Planning and Design System

    Lilić Nikola, Stanković Ranka, Obradović Ivan (2013)
    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 ...
    hybrid systems, mine ventilation, expert systems
    ... maintenance, in order to secure the highest possible level of system use and effectiveness. The final phase in the outlined design process is state evaluation and modification. All parameters of mine ventilation obtained by monitoring have to be compared with designed parameters and when differences are ...
    ... upgrading existing mathematical models with knowledge acquired through engineering practice. Implementation and maintenance System monitoringDesign Evaluation and modification Data acquisition System planing Fig. 1. Component diagram of the novel design concept The outlined system (Figure 3) permits ...
    ... object-oriented approach implemented as a system of frames offers a suitable formalism for the proposed decomposition of the ventilation state evaluation problem, since they both posses a hierarchical structure. The outlined features of the knowledge base alleviate both the coordination of knowledge ...

  • INVENTS: a hybrid system for subsurface ventilation analysis

    Nikola Lilić, Ranka Stanković, Ivan Obradović (2000)
    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 ...
    ... maintenance, in order to secure the highest possible level of system use and effectiveness. The final phase in the outlined design process is state evaluation and modification. All parameters of mine ventilation obtained by monitoring have to be compared with designed parameters and when differences are ...
    ... upgrading existing mathematical models with knowledge acquired through engineering practice. Implementation and maintenance System monitoringDesign Evaluation and modification Data acquisition System planing Fig. 1. Component diagram of the novel design concept The outlined system (Figure 3) permits ...
    ... object-oriented approach implemented as a system of frames offers a suitable formalism for the proposed decomposition of the ventilation state evaluation problem, since they both posses a hierarchical structure. The outlined features of the knowledge base alleviate both the coordination of knowledge ...

  • Terminology Acquisition and Description Using Lexical Resources and Local Grammars

    Cvetana Krstev, Ranka Stanković, Ivan Obradović, Biljana Lazić (2015)
    Acquisition of new terminology from specific domains and its adequate description within terminological dictionaries is a complex task, especially for languages that are morphologically complex such as Serbian. In this paper we present an approach to solving this task semi-automatically on basis of lexical resources and local grammars developed for Serbian. Special attention is given to automatic inflectional class prediction for simple adjectives and nouns and the use of syntactic graphs for extraction of Multi-Word Unit (MWU) candidates for ...
    ... with ranking of results; 4.2. Removing MWUs already in e- dictionaries and those with rank under the specified threshold; 4.3. Linguistic evaluation of grammatical cor- rectness of remaining MWUs; 4.4. Assessment of domain relevance of each MWU by comparing its frequency in the domain text ...
    ... plural and singular forms, then both forms of lemmas will be offered. Production of correct MWU lemmas is a pre- requisite for the successful evaluation. Moreover, entries for morphological e-dictionary of MWUs can be produced only from correct MWU lem- mas. Finally, as a byproduct of the whole ...
    ... MWU inflectional classes for newly retrieved MWUs are obtained – they are derived directly from local grammars used for their extraction. 4.3 Evaluation of performance of MWU extraction In order to evaluate our approach, we applied it to a collection of 74 papers in Serbian from the journal ...