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Упит dcterms_subject_txt:Matematički modeli

801 items

  • Fuzzy stohastički model izbora sistema otvaranja podzemnog rudnika

    Saša M. Jovanović (2016-05-16)
    Investiciono okruženje skopčano sa rudarskom industrijom je veoma svojstveno kada seuporedi sa okruženjima koje susrećemo u tipičnim proizvodnim industrijama. Neke odkarakterisitka rudarstva, koje su često naznačene kao jedinstvene su: visok intenzitetinvesticija, dugi predproizvodni periodi, visok rizik i neobnovljivost resursa.Investiranje u sistem otvaranja rudnika predstavlja dobar primer ireverzibilneinvesticije. Takva investicija zahteva pažljivu analizu, jer nakon njene realizacije ona sene može nadoknaditi bez značajnog gubitka vrednosti. Očigledno je da izbor sistemaotvaranja podzemnog rudnika pripada strateškom planiranju...
    otkopavanje; otvaranje; mreže i grafovi; fuzzy skupovi; stohastičkiprocesi; indeks konveksnosti; sistemi podrške odlučivanju
    ... ograničenje koje se mora uzeti u obzir pri matematičkom opisivanju posmatranog sistema, odnosno sistem se ne može matematički opisati determinističkim modelima. U ovakvim uslovima, matematičko modeliranje sistema zasniva se na proširivanju determinističkog modela uvođenjem slučajnosti. Ove slučajnosti ...
    ... potrebne infrastrukture i troškova transporta rude kao najznačajnih. Ovakav model je bio razvijen u svrhu optimizacije eksploatacije dva podzemna rudnika zlata. Brazil i drugi [6], daju precizan opis matematičkog modela za mrežu niskopa, pri čemu vrše optimizaciju troškova sa stanovišta iznalaženja ...
    ... min. 3.2.2 Osnove Teorije mreža U terminologiji Teorije mreža, mreža je matematički model koji predstavlja skup čvorova i grana koje povezuju parove čvorova [31]. Kompleksna mreža je jedan 38 apstraktni model i može se koristiti za predstavljanje podzemnog rudnika pri različitim nivoima ...

  • Characterization of the eastern Suva Planina Mt. karst aquifer (SE Serbia) by time series analysis and stochastic modelling

    Branislav Petrović, Veljko Marinović, Zoran Stevanović (2023)
    Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • The Dictionary of the Serbian Academy: from the Text to the Lexical Database

    Ranka Stanković, Rada Stijović, Duško Vitas, Cvetana Krstev, Olga Sabo (2018)
    In this paper we discuss the project of digitization of the Dictionary of the Serbo-Croatian Standard and Vernacular Language. Scanning and character recognition were a particular challenge, since various non-standard character set encoding was used in the course of the almost 60-year long production of the dictionary. The first aim of the project was to formalize the micro-structure of the dictionary articles in order to parse the digitized text of and transform it into structured data stored in relational lexical database. This approach ...
    computer lexicography, lexical database, language resources, dictionary, Serbian language
    ... published. For the de- velopment of the lexical database model for the DSA, a similar approach was used as in Stanković et al. (2018) for the Serbian morphological electronic dictionary. The main class, in the core of this dic- tionary model, is LexicalEntry, representing a headword of the dictionary ...
    ... as outlined in Stijović and Stanković (2017). Figure 4: Database model with mapped dictionary article segments. For languages with complex morphology, such as Serbian, information about inflection is very im- portant. In our model we used the class Forms to store the information related to the inflected ...
    ... ontologies (TEI, LMF, Ontolex, LexInfo). A lexical database mod- el was designed in compliance with these structured forms, following mostly the lemon model. Mapping of the lexical entry markers to LexInfo and TEI enabled export of the lexical data to the mentioned formats. A software solution for the ...

  • Faktori uticaja na izbor optimalnog sistema odbrane od podzemnih voda kod površinskih kopova

    Dragoljub Bajić, Dušan Polomčić (2015)
    hydrodynamic model, multi-criteria optimization, openpit mine

  • Mapping and classifying large deformation from digital imagery: application to analogue models of lithosphere deformation

    Taco Broerse, Nemanja Krstekanić, Cor Kasbergen, Ernst Willingshofer (2021)
    kontinentalna tektonika: kompresija, kontinentalna tektonika: ekstenzija, kontinentalna tektonika: transkurentni i transformni rasedi, pukotine, rasedi, zone snažnih deformacija, kinematika deformacija kore i omotača, teorijska mehanika, modelovanje
    ... have designed a model setup such that different regions of the model experience a wide range of different types of deformation: strike-slip faults (simple shear), normal faulting (extension) and thrust faulting (shortening). In the later stages of the model evolution, a part of the model undergoes a clockwise ...
    ... Diff. Stress (Pa) 0 2 1 C om pression S trik e -s lip N V 30° 4.5° clockwise rotation Figure 11. Model set-up: (a) Initial model set-up. All numbers are in centimeters. (b) Model configuration at the end of the experiment. Moving plate kinematics include the first step of 4 cm of translation ...
    ... cross-sections at three different locations. The top two sand layers have been added after finalizing the model to stabilize the model topography; the black dashed line indicates the original model topography. Cross-section a–a’ (top right) shows the main N-S dextral strike-slip zone, with superimposed ...

  • Stochastic simulation and prediction of turbidity dynamics in karst systems. Case study: Mokra karst spring (SE Serbia)

    Veljko Marinović, Branislav Petrović (2021)
    karst spring, stochastic modeling, ARCR model, Serbia

  • Simulation of Migration of Nitrate Contamination in Epikarst Groundwater: A Column Laboratory Method

    Branislav Petrović (2021)
    epikarst, model, nitrate, electrical conductivity

  • Primena fuzzy optimizacije u hidrodinamičkoj analizi

    Dragoljub Bajić, Dušan Polomčić, Jelena Ratković, Predrag Pajić (2018)
    znanje eksperta, optimizacija, trougaoni fuzzy brojevi, upravljanje podzemnim vodama, fuzzy logika, hidrodinamički model

  • Machine Learning and Deep Neural Network-Based Lemmatization and Morphosyntactic Tagging for Serbian

    Ranka Stanković, Branislava Šandrih, Cvetana Krstev, Miloš Utvić, Mihailo Škorić (2020)
    The training of new tagger models for Serbian is primarily motivated by the enhancement of the existing tagset with the grammatical category of a gender. The harmonization of resources that were manually annotated within different projects over a long period of time was an important task, enabled by the development of tools that support partial automation. The supporting tools take into account different taggers and tagsets. This paper focuses on TreeTagger and spaCy taggers, and the annotation schema alignment ...
    Part-of-Speech tagging, lemmatization, corpus, evaluation, Serbian, morphological dictionary
    ... (DNNs) (Huang et al., 2015; Choi, 2016; Akbik et al., 2018). The first operational tagger and lemmatization model for Serbian were produced as a parameter file (TT11) for the TreeTagger model (Schmid, 1999) after a thorough anal- ysis of the state-of-the-art solutions (Popović, 2010), and subsequently ...
    ... two taggers trained on the largest train- ing set (SR-{100}). We used it to train the following tag- gers: 1) SerSpaCy, a spaCy model, and 2) TT19, a Tree- Tagger model. We used T11 as the baseline for evaluation, since it was already tested and evaluated as part of a pre- vious research (Popović ...
    ... final schema in Subsection 3.2. The main fea- tures of the tools used for tagging are described in Subsec- tion 3.3. Evaluation results of spaCy model are compared with the results obtained by the TreeTagger trained on the same dataset, as well as with a previous version of TreeTag- ger for Serbian ...

  • Optimizacija parametara reza rotornog bagera pri otkopavanju materijala sa povećanom čvrstoćom

    Saša D. Bošković (2016-09-09)
    Otkopavanje materijala rotornim bagerom je veoma sloţen fiziĉko-mehaniĉki proces. Pokazatelji efektivnosti tog procesa zavise od velikog broja raznovrsnih ĉinilaca od kojih se posebno mogu istaći: fiziĉko-mehaniĉke karakteristike materijala koji se otkopava, reţim rada bagera i izbor tehnoloških parametara bloka, odreska i reza, geometrije vedrica i zuba itd. Poseban problem se javlja kod otkopavanja materijala povećane ĉvrstoće, što je ĉest sluĉaj na našim površinskim kopovima. Dimenzionisanje specifiĉne sile kopanja bagera prema manjim masama izuzetno ĉvrstog materijala je neracionalno i rešenje ...
    rotorni bager, parametri reza, otpor na kopanje, dinamika bagera, kapacitet, optimizacija, specifična potrošnja energije
    ... .. 117 Slika 5.8. Model strele rotora ............................................................................. 124 Slika 5.9. Model rotora ....................................................................................... 125 Slika 5.10. Raĉunski modeli strele rotora ......... ...
    ... nauĉni doprinos kroz definisanje metodologije, izradu simulacionog modela rada rotornog bagera, izradu modela radnog organa rotornog bagera (strele i rotora) metodom konaĉnih elemenata i terenska merenja koja će verifikovati model rada bagera i dinamiĉko ponašanje pri otkopavanju materijala sa povećanom ...
    ... bagera; 8 - Definisanje metodologije kroz izradu simulacionog modela rada rotornog bagera, izradu modela radnog elementa rotornog bagera (strele i rotora) metodom konaĉnih elemenata i terenska merenja koja će verifikovati model rada bagera i dinamiĉko ponašanje pri otkopavanju materijala sa ...

  • Production information system of the Pljevlja coal mine

    Božo Kolonja, Ranka Stanković, Filip Vuković (2018)

  • Numerical simulation of the Late Jurassic closure of the Vardar Tethys

    Nikola Stanković, Vesna Cvetkov, Vladica Cvetković (2021)
    ... utilizes marker in cellapproach with finite difference discretization of equations on a staggered grid [Gerya et al., 2000;Gerya&Yuen, 2003]. The 2D model consists of two continental plates separated by two oceanic slabs connected at amid-oceanic ridge. Intraoceanic subduction is initiated along the ridge ...
    ... ridge by assigning a weak zonebeneath the ridge. Time-dependent boundary conditions for velocity are imposed on thesimulation in order to model a transient spreading period. The change of sign in plate velocities isfound to be useful for both obtaining obduction / ophiolite emplacement [Duretz et al. ...
    ... two convergent phases separated bya single divergent phase where spreading regime is dominant. Effect of duration and magnitude ofthe second phase on model evolution is also explored. Our so far obtained simulations were able to reproduce the westward obduction and certainextension processes along the active ...

  • 2D Numerical Simulation of Intraoceanic Subduction during the Upper Jurassic Closure of the Vardar Tethys

    Nikola Stanković, Vesna Cvetkov, Vladica Cvetković (2020)
    ... utilizes marker in cellapproach with finite difference discretization of equations on a staggered grid [Gerya et al., 2000;Gerya&Yuen, 2003]. The 2D model consists of two continental plates separated by two oceanic slabs connected at amid-oceanic ridge. Intraoceanic subduction is initiated along the ridge ...
    ... ridge by assigning a weak zonebeneath the ridge. Time-dependent boundary conditions for velocity are imposed on thesimulation in order to model a transient spreading period. The change of sign in plate velocities isfound to be useful for both obtaining obduction / ophiolite emplacement [Duretz et al. ...
    ... two convergent phases separated bya single divergent phase where spreading regime is dominant. Effect of duration and magnitude ofthe second phase on model evolution is also explored. Our so far obtained simulations were able to reproduce the westward obduction and certainextension processes along the active ...

  • Stochastic Prediction of Temporal Variations of Karst Groundwater Regime in Function of Sustainable Management: Case Study Mokra Karst Spring (SE Serbia)

    Veljko Marinović, Branislav Petrović (2021)
    karst groundwater, stochastic model, water quality, early warning system

  • Concept od predictive hydrodynamic calculations: An overview of the case studies from Serbia

    Dušan Polomčić, Dragoljub Bajić, Jelena Ratković, Vesna Ristić Vakanjac, Marina Čokorilo Ilić (2019)
    groundwater management, hydrodynamic model, multiple-criteria decision making, open cast mine, groundwater source.0

  • An oilfield in Libya: A new model to enhance waste water disposal

    Dušan Danilović, Vesna Karović Maričić, Nori Elhaddad, Branko Leković (2016)
    нафта, лежишне воде, припрема

  • Дефинисање археолошких објеката на локалитету Кремените њиве применом Ојлерове 3Д деконволуције на магнетометријске податке

    Весна Цветков, Илија Васиљевић, Бранислав Сретеновић, Весна Дамњановић (2018)
    ...  Razmatran je model obli‐ ka prizme, konačne debljine, na manjoj i većoj dubini zaleganja, kao  i model na kome je prikazano više  tela na različitim dubinama, koja se nalaze u sredini koja ima različitu vrednost magnetske susceptibilosti  u odnosu na zadata tela. Za formiranje sintetičkih modela korišćene su  ...
    ...  polja sa rastojanjem  od  uzročnika  anomalija.  Za  jednostavne modele  se  tumači  kao  strukturni  indeks  (Thompson,  1982)  i  definiše vrstu mete korišćene u proceduri O3DD (Reid i dr, 1990).  U radu su na sintetičkim modelima testirane Standardna  i Locirana O3DD sa različitim struktur‐ nim ...
    ... to magnetic  inclination, declination and  remanent magnetization  (Bastani & Kero, 2004). A  model of a prism of definite thickness which lies on shallower and deeper depth was considered, as well  as the model on which are shown several bodies at different depths,  in an environment with different  m ...

  • Towards translation of educational resources using GIZA++

    Ivan Obradović, Dalibor Vorkapić, Ranka Stanković, Nikola Vulović, Miladin Kotorčević (2016)
    ... dX.clean 1 80 Language Model Training A language model (LM) is used to ensure fluent output, built with the target language, in our case English. Following script creates lm folder, positions in it and finally execute command that will build an 3-gram language model. mkdir ~/lm cd ~/lm ...
    ... about the text: ~/mosesdecoder/scripts/recaser/train-truecaser.perl \ --model ~/corpus/truecase-model.en --corpus \ ~/corpus/edX.tok.en ~/mosesdecoder/scripts/recaser/train-truecaser.perl \ --model ~/corpus/truecase-model.sr --corpus \ ~/corpus/edX.tok.sr Finally ...
    ... perl \ --model ~/corpus/truecase-model.en \ < ~/corpus/edX.tok.en \ > ~/corpus/edX.true.en 1 http://www.statmt.org/moses/glossary/SMT_glossary.html ~/mosesdecoder/scripts/recaser/truecase.perl \ --model ~/corpus/t ...

  • Part of Speech Tagging for Serbian language using Natural Language Toolkit

    Ranka Stanković, Boro Milovanović (2020)
    Dok se razvijaju složeni algoritmi za NLP (obrada prirodnog jezika), osnovni zadaci kao što je označavanje ostaju veoma važni i još uvek izazovni. NLTK (Natural Language Toolkit) je moćna Python biblioteka za razvoj programa zasnovanih na NLP-u. Pokušavamo da iskoristimo ovu biblioteku za kreiranje PoS (vrsta reči) oznake za savremeni srpski jezik. Jedanaest različitih modela je kreirano korišćenjem NLTK API-ja za označavanje. Najbolji modeli se transformišu sa Brill tagerom da bi se poboljšala tačnost. Obučili smo modele na označenom ...
    obrada prirodnog jezika, mašinsko učenje, neuronske mreže
    ... will be used for comparing different taggers. The simplest model in NLTK is Default tagger which tags every token with one selected PoS category [17]. Because the noun is by far the most represented PoS tag, the accuracy for this model on all tokens will be exactly 21,51%. This is the baseline tagger ...
    ... reasoning. NLTK API makes it possible to create multiple standalone tagger models as well as to combine them. We are going to try and test every model available in the version 3.5 released in March 2020. Having a plethora of different algorithms makes this library a good choice for a research. ...
    ... is picked. At the end of the chain, there is a rule which states that the word is of Noun category – same as for Default tagger. Obviously, this model AII 1.1.2 will perform better than the baseline tagger, but making the right rules demands significant effort. We did not invest much time in ...

  • Towards a Mining Equipment Ontology

    Ranka Stanković, Ivan Obradović, Olivera Kitanović, Ljiljana Kolonja (2012)
    ... equipment. The structure of RudOnto can be described by an UML (Unified Modeling Language) model, as depicted in Figure 2. A brief description of this model follows. The lexicographic superclass within the model is the class Rečnik, implemented as an abstract class. Concepts, which can be either general ...
    ... domain. At the same time an ontology is a data model of the domain and it can be used for drawing inferences on the basis of the information stored in the objects within that domain and the interconnections existing between them. 3 2.2. Model of the RudOnto terminological resource RudOnto ...
    ... relation in the model is implemented by involution, which means that a hyponym can appear only once in the resource hierarchy, with only one hypernym above it. Other semantic relations between concepts are enabled by the RelacijeTermina class, whereas the MultijezičkiLeks class in the UML model is used for ...