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Упит dcterms_subject_txt:numeriki modeli,neuronske mreže

860 items

  • Geotehnički uslovi izgradnje metro stanice „Savski trg“ – beogradski metro linija 1

    Dragoslav Rakić, Nemanja Stanić, Josip Išek, Slavoljub Stojković (2023)
    Ukrštanje linija 1 i 2 beogradskog metroa, planirano je na lokaciji “Savski trg” gde će se izgraditi zajednička metro stanica. Zbog složene konstrukcije objekta i različite dubine dijafragmi, koja na delu metro linije 2 iznosi preko 40 m, planirana je fazna izgradnja. U vezi sa tim u radu je prikazan način definisanja geotehničkog modela, kao i geotehnički proračuni u kojima su analizirani: fazni načini iskopa, filtraciona analiza, uticaj pornih i efektivnih napona na stabilnost dijafragme, horizontalna i vertikalna ...
    beogradski metro, metro stanica, geotehnički model, stabilnost dijafragme, horizontalna pomeranja, vertikalna pomeranja

  • Inženjerskogeološka istraživanja za potrebe izgradnje tunela T1 na putnom pravcu Požega-Kotroman

    Andrija Popović (2024)
    Tokom izrade završnog rada korišćeni su podaci koje sam dobio u saradnji sa firmom „Saobraćajni institut CIP d.o.o.“, kao i ostala odgovarajuća stručna literatura.Osnovni cilj pisanja rada jeste definisanje određenih fizičko mehaničkih parametara i predlog podgrade i načina iskopa tunela na osnovu RMR klasifikacije.
    stenska masa, RMR klasifikacija, tunel, inženjerskogeološka istraživanja
    ... sa povremenom ugradnjom armaturne mreže Sistematsko sidrenje 4 m dužine, na rastojanju 1,5 do 2m u kruni i duž zidova i sa armaturnom mrežom u kruni Sistematsko sidrenje 4 - 5m dužine na rastojanju 1 — 1,5 m u kruni i duž zidova sa armaturnom mrežom Sistematsko sidrenje 5 – 6 m dužine ...
    ... Ugradnja podgradesa iskopom. | u kruni i duž zidova sa Ngr nja podgTi p 150 mm na anošenje armaturnom - stranama i 50 sloja prskanog | betona ” mrežom. Sidrenje izvršitii u | mmna licu odmah nakon miniranja podnožnom svodu Minuti Sati Dani Meseci Godine ı0 30 ı iLU I 235 I020 ı 2445 IO 2345 IO ...
    ... ISKOPA - _ Dovršiti osiguranje iskopa 20m od čela iskopa PREPORUČENI TIP - _ Lokalna sidra u svodu 3 m dužine, na razmaku 2.5 m sa mestimično čeličnom mrežom PODGRADE - Torktretiranje 50 mm u svodu gde je potrebno PREPORUČENO VREME 1 godina za raspon od 10 m STAJANjA BEZ PODGRADE i o i - PREPORUČENI ...

  • A Fuzzy Expert Model for Availability Evaluation

    Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić (2019)
    Each technical system within itself carries the great potential danger of possible occurrence of failure and damages. Mining machines are characteristic by great investment values, costs of unplanned shutdowns, complex working conditions, and environment and workers hazards. Systematic monitoring of the mining machinery is of great importance for the management of the mining companies. Availability is the overall concept of quality of service. Includes information regard to operating state, an idle state, a standby state and shut down. The ...
    raspoloživost, ekspertski sistem, fazi teorija, buldozeri
    ... III. AVAILABILITY ASSESSMENT MODEL Figure 1 shows the conceptual model of the expert system for availability (A) evaluation based on fuzzy interference of reliability (R), maintainability (M) and supportability (S) input data. Input data are introduced to a model based on experts’ opinions. ...
    ... Измењено: 2023-10-14 04:10:15 A Fuzzy Expert Model for Availability Evaluation Dejan Ivezić, Miloš Tanasijević, Predrag Jovančić, Radiša Đurić Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] A Fuzzy Expert Model for Availability Evaluation | Dejan Ivezić, Miloš ...
    ... but requires specific, quite complex IT system. Therefore, in this paper, an expert model, that integrates reliability, maintainability, and supportability in the measure of availability is proposed. This model is based on fuzzy sets theory and it is implemented to three types of bulldozers that ...

  • Influence of DEM resolution on numerical modelling of debris flows in RAMMS - Selanac case study

    Jelka Krušić, Biljana Abolmasov, Mileva Samardžić Petrović (2019)
    Debris flows induced by intensive rainfall represent very hazardous phenomena in many parts of the World. Methods for prediction of runout distance of flow like mass movements are different and depending on the input data, rheology, and available or appropriate numerical solution. However, sometimes it is not easy to obtain pre event and post event high-resolution data in the rural or mountainous area. Thus, the topology of terrain is the most important input parameter for the every real case ...
    tecišta, modeliranje, RAMMS, DEM
    ... 2007; Frank, 2017). As input, three quantities must be specified to perform a numerical calculation: (1) a digital elevation model (DEM), (2) source zone area and (3) model friction parameters. Pre- event DEM resolution characterizes the natural terrain surface geometry and it is therefore the most ...
    ... resolution affected a lot in results about deposition depth, but also on choosing right frictional parameter in rheological model. Method One of well used rheological model is Voellmy method (Voellmy, 1955) firstly used in snow avalanche models, which means that is basically one-phase. It is assumed ...
    ... precision in calculated eroded material, which is quite deep in this case. Input Data RAMMS uses DEM (Digital Elevation Model) as a basic data for defining simple geometry of model. Some researchers suggested 5x5m resolution as an optimal, explaining that even using smaller resolution gave quite similar ...

  • Numerical modeling of Selanac debris flow propagation using SPH code

    Jelka Krušić, Biljana Abolmasov, Miloš Marjanović, Manuel Pastor, Saeid M. Tayyebi (2021)
    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 ...
    debris flow, modelling, SPH code, DEM
    ... and high resolution Digital Terrain Model (DTM), also. Final models show accurate results comparing to the depths in deposition zone, but actual run-out distance of debris flow was longer than the measured run-out distance obtained by the SPH simulation model. Also, simulation results show heights ...
    ... velocity as well as pore water pressure if coupled model is included. Geoflow SPH proposed by Pastor 2009, already has been used on different cases in the world (Pastor et al. 2015, 2009, Cascini et al. 2014, Cuomo et al. 2014).Within the SPH model, it is possible to incorporate numerous rheological ...
    ... SPH model proposed by Pastor et al. (2009), defines propagations of mass as mixture of soil and water particles with calculation of velocity. In addition, calculation of pore water pressures propagation is possible to be obtained using Finite Difference Method coupled with two- phase model. Herein ...

  • Model upravljanja investicionim projektima otvaranja površinskih kopova uglja

    Cvjetko P. Stojanović (2015-04-27)
    Brze promene u okruženju pred rukovodioce postavljaju mnogobrojne zahteve,pre svega, one koji se tiču ostvarenja ciljeva u zadatom vremenu i raspoloživimsredstvima što zahteva fleksibilan pristup u organizovanju aktivnosti i efikasnost unjihovom sprovođenju.Upravljanje projektima, bilo koje vrste, suštinski, predstavlja veoma složenproces odlučivanja uslovljen velikim brojem ulaznih faktora. Ti faktori treba daomoguće fokusiranje na prioritete i ciljeve, praćenje realizacije, fleksibilnost uprevazilaženju teškoća, prilagođavanje promenama, te kontrolu nad ostvarenimrezultatima. Ovakav način upravljanja zahteva korišćenje proverenih tehnika i alata tetimski rad angažovanih na ...
    Projekat, upravljanje, metodologija, površinska eksploatacija, model

  • Electronic Dictionaries - from File System to lemon Based Lexical Database

    Ranka Stanković, Cvetana Krstev, Biljana Lazić, Mihailo Škorić (2018)
    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 ...
    ... e-dictionaries to XML files compliant to LMF model, but further exploitation of these files was not implemented, neither for lexical database development nor for further processing (Stanković et al., 2013). Finally we considered the lemon model (Lexicon Model for Ontologies), which was derived from ...
    ... The main advantage of the lemon model for the research outlined in this paper was its support for linking with other (lexical) data and the possibility to access data by using the standardized SPARQL query language. The model pre- sented is based on the lemon model, but some modifica- tions and ...
    ... presented a new database model, developed upon the lemon model, as well as its application for mi- grating electronic morphological dictionaries from a single- user file system to a multi-user environment based on a re- lational database management system. The new lexical data model implemented as a lexical ...

  • The Impact Assessment of NO2 Emission from District Heating Plant on Local Air Quality, the Case of Zemun, Belgrade

    Boban Pavlović, Uroš Pantelić, Marija Živković, Dejan Ivezić (2021)
    The Belgrade district heating system relies on fossil fuels in heat production, where natural gas has the largest share of around 95% and fuel oil with around 4.4%. The Zemun heating plant is completely fueled with fuel oil. Currently, it is the largest plant that is not fueled with natural gas. The objective of this paper is to assess the impact of NO2 from the Zemun heating plant on local air quality by analyzing and comparing the concentration of ...
    NO2, Zagađenje vazduha, Kvalitet vazduh na lokalnom nivou, Model disperzije, AERMOD, Daljinsko grejanje, Beograd

  • Geologic Information System of Serbia

    Branislav Blagojević, Branislav Trivić, Ranka Stanković, Nenad Banjac, Olivera Kitanović (2011)
    Geologic information system of Serbia (GeolISS) represents repository for digital archiving, query, retrieving, analysis and geologic data visualization. The GeolISS is implemented through ESRI ArcGIS technology, and is designed to operate as a personal geodatabase (MS Jet 4.0 Engine) and SDE enterprise geodatabase in MS SQL Server. The objective of GeolISS implementation is integration of existing geologic archives, data from published maps at different scales, newly acquired field data, as well as Web publishing of geologic information. Physical implementation ...
    Geologic information system, Conceptual model, Logical model, Implementation, Geodatabase
    ... BRANISLAV TRIVIĆ2, RANKA STANKOVIĆ3, OLIVERA KITANOVIĆ4 and NENAD BANJAC 5 Abstract Keywords: Geologic information system, Conceptual model, Logical model, Implementation, Geodatabase. Geologic information system of Serbia (GeolISS) represents repository for digital archiving, query, ...
    ... acquired field data, as well as Web publishing of geologic information. Physical implementation of GeolISS has been guided with conceptual and logical model in those specified the basic kinds of geologic entities of interest and how they are described. The attempt has been influenced by NADM-C1 imp ...

  • Agent-based modeling as a support to an expert-based approach: Exploring individual heating systems transition

    Boban Pavlović, Marija Živković, Dejan Ivezić (2022)
    Expert-based energy scenarios are mainly developed following assumptions of experts and, in most cases, a limited number of stakeholders. Such an approach will provide satisfactory results in centrally managed energy sectors where further decisions could be envisaged relatively precisely (electricity production/distribution, district heating systems, etc.). The same approach will provide more uncertain outcomes of future energy structure in the household sector, where decisions related to consumption, selection of energy source, or application of specific technology are made by numerous ...
    Energetska tranzicija, Grejanje domaćinstava, Individualni sistemi grejanja, Energetsko planiranje, Integrisano energetsko planiranje, ABM, LEAP, Srbija

  • AR, CR and ARCR modeling for simulations and analyses of karst groundwater quality parameters

    Vesna Ristić-Vakanjac, Marina Ćokorilo-Ilić, Petar Papić, Dušan Polomčić, Radisav Golubović (2018)
    Although an invisible component of the hydrologic cycle, groundwater generally takes precedence over other water resources in the area of drinking water supply. Among groundwater resources, karst aquifers tend to be rich in sufficiently-accessible amounts of high-quality water. During most of the year, this water requires only disinfection prior to delivery to the end user. However, in many cases extreme rainfall and/or sudden snow melt results in transient turbidity, increase in bacterial count and temporary contamination (e.g. increase in ...
    autocorrelation, cross-correlation, autoregressive model, cross-regressive model, autocross regressive model, nitrates, Banja Spring, Serbia.

  • Optimizacija utovarno-transportnih sistema u funkciji planiranja površinskog kopa

    Mirjana V. BANKOVIĆ (2018)
    tehnološki model, integralni model, planiranje, optimizacija,utovarno-transportni sistem, neto sadašnja vrednost projekta

  • Soil oscillation law parameter determination with the application of Lagrange’s theorem at “Kovilovača“ open pit

    Suzana Lutovac, Nebojša Vidanović, Čedomir Beljić, Zoran Gligorić (2015)
    ... načina tj. modela, koristeći pri tome vrednosti dobijene eksperimen- talnim merenjima. ♦ Određivanje parametara po modelu 1 Za dobijanje parametara (K) i (n) uglav- nom se koristi metoda najmanjih kvadrata, koja predstavlja uobičajeni model 3 . ♦ Određivanje parametara po modelu 2 U zakonu ...
    ... experimental measurements. ♦ Determination of parameters by model 1 The smallest square method is mainly used to obtain the parameters K and n which represents a common model [3]. ♦ Determination of parameters according to model 2 In the rock mass oscillation velocity law given by equation ...
    ... A. Sadovski. Za određivanje parametara u jednačini Sadovskog, pored uobičajenog modela - metode najmanjih kvadrata, prikazan je još jedan model uz primenu Lagranžove teoreme. Pri tom je konstatovano da se oba modela mogu koristiti za izračunavanje brzine oscilovanja stenske mase. Ključne reči: ...

  • Izbor optimalnog sistema bager damper primenom modela simulacije na površinskom kopu rudnika bakra Majdanpek

    Kosta Prstić (1980)
    Površinski kopovi, bager, damper, bakar, Majdanpek

  • Prognoza operativne efikasnosti aktivnog podzemnog rudnika zasnovana na teoriji sivih sistema

    Svetlana M. Štrbac-Savić (2016-06-10)
    Efikasnost predstavlja preduslov za opstanak svake rudarske kompanije, posebno u uslovima izuzetno konkurentnog trţišnog okruţenja kao što je to rudarska industrija. Efikasnost oznaĉava sposobnost kompanije da ispuni svoje kratkoroĉne ili dugoroĉne ciljeve. Operativna efikasnost se definiše kao odnos izmeĊu ulaznih parametara potrebnih za odvijanje proizvodnje i pokazatelja dobijenih proizvodnjom. U kontekstu rudarskog poslovanja, operativna efikasnost se odnosi na vreme potrebno da se mineralno dobro transformiše u novĉana sredstva. Visoka operativna efikasnost se postiţe kada se ostvari prava kombinacija karakteristika ...
    podzemni rudnik, operativna efikasnost, prognoza, teorija sivih sistema, stohastiĉke diferencijalne jednaĉine, simulacija
    ... inţenjerskih primena:  razvoj modela,  definisanje parametara sistema, 10  predikcija Razvoj modela predstavlja opis kako se sistem ponaša, prvo kvalitativno izraţeno uslovima, dogaĊajima, mehanizmima i postupcima koji su ukljuĉeni u model ("konceptualni model") a zatim kvantitativno izraţeno ...
    ... , .k n (3.6) 36 U Teoriji sivih sistema, sivi multiparametarski model (Multi-variable grey model MGM(φ, m)) oznaĉava sivi model u kom je φ red diferencijalne jednaĉine, а m je broj promenljivih u modelu. MGM(φ, m) se definiše na sledeći naĉin [CHANG09]:             ...
    ... deterministiĉkim modelima. U ovakvim uslovima, matematiĉko modeliranje sistema zasniva se na proširivanju deterministiĉkog modela uvoĊenjem sluĉajnosti. Ove sluĉajnosti se opisuju terminima verovatnoće i krajnji ishod je stohastiĉki model sistema. Uopšteni oblik stohastiĉkog modela predstavljen je ...

  • Development of the Cost-Based Model for Monitoring the Lifetime of the Earth Moving Machines

    Ugljesa Bugarić, Milos Tanasijević, Stevan Djenadić, Dragan Ignjatović, Ivan Janković (2022)
    This paper presents the model for the identification of reference points on the lifetime curve of engineering systems. This curve commonly represents the increase and decline of failure in relation to time. A direct correlation between failure rate and costs is assumed in this paper, therefore, statistical and empirical analysis of costs provided reference points. This approach is used for positioning stages of the engineering system’s lifetime with a minimal number of failures and costs, regardless of whether these ...
    Electrical and Electronic Engineering,Industrial and Manufacturing Engineering, Control and Optimization, Mechanical Engineering, Computer Science (miscellaneous), Control and Systems Engineering

  • Оптимизација управљања процесима рекултивације површинских копова угља

    Bojan S. Dimitrijević (2014-05-30)
    Ширење површинске експлоатације минералних сировина а нарочито енергетских ресурсафосилних горива, чине површинске копове угља просторно доминантним објектима великих рударскихбасена како у нас тако и у свету. Експлоатациона активност, прати негативне еколошке утицаје наживотну средину шире околине, што нас обавезује на интегрално планирање, ревитализацију,рекултивацију и уређење нарушеног простора за његово поновно хумано коришћење упостексплоатационом периоду. Постексплоатационо санирање и уређење предела површинских коповаи одлагалишта односно нарушеног простора изазваног рударским радовима и пратећих објеката,представља синтетички мултидисциплинарно-интердисциплинаран веома комплексан вишефазниинжењерски пројектни задатак.У уводном ...
    рекултивација, постексплоатациони предео, површински коп угља,вишеатрибутна анализа, одлучивање, процеси, рекултивационо решење
    ... више мултикритеријумских модела, у зависности према начину укључивања доносиоца одлуке (ДО) у поступак [4, 35, 14]. 1. Модели за одређивање неинфериорних решења 2. Модели са унапред израженим преференцијалом 3. Интерактивни модели 4. Стохастички модели 5. Модели компромисног програмирања ...
    ... односно математички модел. Ако математички модел добро репрезентује проблем, тада ће и решење добијено помоћу модела бити добро решење датог проблема. У инжењерској пракси планирања система користи ce прилаз дискретних модела када ce, уместо израде свеобухватног математичког модела, пројектују варијантна ...
    ... површинских копова као истраживачких полигона изабран је модел PROMETHEE. Без улажења у анализу и оцену вишеатрибутних модела, при избору модела превагу је имало искуство у његовом коришћењу, постигнути резултати и уграђеност у PROMETHEE модел шест генерализованих критеријума за исказивање преференција ...

  • Numerical Models of Debris Flows with Entrainment Analysis-Case Studies from the Republic of Serbia

    Jelka Krušić , Biljana Abolmasov, Miloš Marjanović (2021)
    The results of material entrainment analysis in RAMMS debris flow software, as well as numerical models of final flow heights for two case studies from the Republic of Serbia are presented. Both of debris flow cases started with initial sliding of huge volume block, prolonging to behave as flowing process. Results of the analysis showed that entrainment material affects final results of transportation model, runout distance, deposition area and volume of debris flow. In both cases entrainment volume is very ...
    tecišta, zadržavanje nanosa, RAMMS, validacija

  • Fuzzy expert analysis of the severity of mining machinery failure

    Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković (2020)
    Mining machinery failure is almost an everyday occurrence. Usually the failures bare certain consequences, which require additional financial costs to repair and restore the system to its operational state. The consequences are viewed through negative and damaging effects a failure has on the machine, health and safety of the employees, work environment, and on the environment. The removal of the consequences of the failure requires additional financial investment, which has a negative impact on the company’s business. In order ...
    Severity of failure, Severity of failure assessment, Mining machinery, Fuzzy sets, Fuzzy logic

  • A fuzzy-based decision support model for effectiveness evaluation - a case study of examination of bulldozers

    Miloš Tanasijević, Predrag Jovančić, Dejan Ivezić, Uglješa Bugarić, Radiša Đurić (2019)
    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 ...
    Efikasnost, Fazi zaključivanje, Prikupljanje podataka, Buldozer