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Упит dcterms_creator_txt:Litvinov Yuri A.

1498 items

  • Application of machine learning for diagnosing the operation of a deep well pump in oil production

    Maja Trikić (2024)
    This paper will thoroughly examine how machine learning can improve the diagnosis of deep well pumps by analyzing the role and function of the pumps, dynamograms, sensor technologies, and diagnostic methods.Our analysis will provide insights into modern techniques and approaches for enhancing the performance and reliability of oil production systems, targeting cost reduction and increased operational efficiency.
    deep well pump, dynamograms, machine learning, diagnostics of operating coditions,Random Forest, XGBoost
    ... aaaaa a a aaaaagaaaaoi 29 7. Instance-Based Learning ... naanaaaanaaaaaaaaaaaaaagatoati 29 8. Model-Based Learning ... ana a anaaaaa a aaaaaaaaaakaaaaoi 29 5. SENSORS FOR MONITORING SUBMERSIBLE PUMPS ..........anann.. 30 5.1. Pressure sensor 5.1.1. Operating principle.....aaaaaaaa a aaaaaa ...
    ... Typical rod pump automation includes instrumentation with load cells and position sensors, a pump shut-off control device, a control panel, and a motor drive, and in some cases, a variable-speed drive. Additionally, a radio for receiving and sending information to/from SCADA (Supervisory Control and Data ...
    ... were tested for a single scale. An example of applying CWT with only one scale to a normalized dynamometric chart from a well is shown in Figure 6.6. 00 02 04 06 08 10 0 2 40 [J P 100 Figure 6.6. Application of CWT with only one scale to a normalized dynamometric chart from a well. Equations ...

  • Natural two-dimensional pyrophyllite: Nanoscale lubricant, electrical insulator and easily-machinable material

    Borislav Vasić, Radoš Gajić, Ivana Milošević, Žarko Medić, Marina Blagojev, Marko Opačić, Aleksandar Kremenović, Dejan Lazić (2022)
    Pyrophyllite, with the chemical formula Al2Si4O10(OH)2, is a naturally occurring and abundant van der Waals mineral belonging to the group of phyllosilicates. It is very soft, layered crystal used for sculpting and an excellent electrical and thermal insulator aimed for the operation at high pressure and temperature. Here, for the first time, two-dimensional (2D) pyrophyllite obtained by both mechanical and liquid phase exfoliation is presented and investigated at the nanoscale. The layered structure provides low friction coefficient of around ...
    Atomic force microscopy, Insulating properties, Nanofriction and wear, Natural two dimensional materials, Phyllosilicates, Pyrophyllite

  • A bilingual digital library for academic and entrepreneurial knowledge management

    Ranka Stanković, Cvetana Krstev, Biljana Lazić, Dalibor Vorkapić (2015)
    A generic knowledge management process of organization, storage and retrieval of knowledge can suitably be fitted in a digital library. In the digital and knowledge age digital libraries can be used in knowledge management to handle intellectual assets and support knowledge creation. A multilingual digital library either stores content in more than one language or provides multilingual query access to monolingual content. In Serbia 18 of 308 scientific journals regularly published are bi-lingual, with papers simultaneously being in English ...
    Knowledge management, Digital library, Multilingualism, Language Resources, Terminology
    ... presented as a list of documents matching the metadata query with links to full-text articles in a PDF format, as well as to a TMX aligned text in an HTML format. Figure 5 shows the result of the previous query for the selected language (English), but selection of language “sr” would retrieve a page with ...
    ... Purpose – A generic knowledge management process of organization, storage and retrieval of knowledge can suitably be fitted in a digital library. In the digital and knowledge age digital libraries can be used in knowledge management to handle intellectual assets and support knowledge creation. A multilingual ...
    ... within a user-friendly platform, with the possibility for a very high level of search refinement. Bibliša also supports the analysis of concepts and concept structures, identifying terms assigned to concepts, and establishing relations between terms in English and Serbian, which makes it a valuable ...

  • Extensive vibrations of the belt conveyer drive electromotor of a bucket wheel excavator as a result of intesified wear-and-tear of its mount support

    Vesna Damnjanović, Predrag Jovančić, Snežana Aleksandrović (2017)

  • Correlation Between Dynamic CBR and Compaction and Bearing Capacity of Pavement Foundation Layers

    Milan Bogdanović, Snežana Bogdanović, Dragoslav Rakić, Irena Basarić Ikodinović (2024)
    This paper presents a dynamic California Bearing Ratio (CBRd) device that can be used on a prepared pavement foundation layer to obtain a certain parameter of the tested material in the laboratory and in situ in a direct and fast way. For the selected natural material (gravel), it is shown that the laboratory CBRd can be used to estimate the compaction and bearing capacity, because it correlates well with the parameters of the standard and modifed Proctor compaction tests. ...
    korelacija parametara, donji slojevi saobraćajnica, laboratorijska i terenska ispitivanja, dinamički kalifornijski indeks nosivosti CBRd
    ... a % - b 200 - ii D tl/(:· AŠ |=} 180 - 70 //E?] “ (-P-4"| AAJA N B D/_T'Jč, ___160 – A “A Ee . PrO M “ A Š Š D n f Č ĆA A -- o B 140 ; _ [- Ž . A a 50 M ~ : AAA AA n 070 - BI A AAAA %Ž mpon-- D A Z AA _ |j A 0 7 O A ŠA -& W m 1 l 100 _Z A a A |} A 30 80 ii CBRa(%) a E iii ...
    ... performed on a subgrade layer made of natural stone aggregate (gravel). The subgrade layer was constructed above the embankment layer, which consist- ed of natural material (sand) in three layers with a thickness of 0.3 m. Spreading was performed in a layer with a thickness of 0.35 m under a loose condition ...
    ... Email: milan.bogdanovic(Ottpaqi.com. This paper presents a dynamic California Bearing Ratio (CBR,) device that can be usedon a prepared pavement foundation layer to obtain a certain parameter of the tested material in the laboratory and in situ in a direct and fast way. For the selected natural material ...

  • A necessary and sufficient condition for an algebraic integer to be a Salem number

    Dragan Stankov (2019)
    We present a necessary and sufficient condition for a root greater than unity of a monic reciprocal polynomial of an even degree at least four, with integer coefficients, to be a Salem number. This condition requires that the minimal polynomial of some power of the algebraic integer has a linear coefficient that is relatively large. We also determine the probability that an arbitrary power of a Salem number, of certain small degrees, satisfies this condition.
    Algebraic integer, the house of algebraic integer, maximal modulus, reciprocal polynomial, primitive polynomial, Schinzel-Zassenhaus conjecture, Mahler measure, method of least squares, cyclotomic polynomials

  • A Data Driven Approach for Raw Material Terminology

    Olivera Kitanović, Ranka Stanković, Aleksandra Tomašević, Mihailo Škorić, Ivan Babić, Ljiljana Kolonja (2021)
    The research presented in this paper aims at creating a bilingual (sr-en), easily searchable, hypertext, born-digital, corpus-based terminological database of raw material terminology for dictionary production. The approach is based on linking dictionaries related to the raw material domain, both digitally born and printed, into a lexicon structure, aligning terminology from different dictionaries as much as possible. This paper presents the main features of this approach, data used for compilation of the terminological database, the procedure by which it has ...
    sirovine, rudarstvo, terminologija, rečnik, terminološka aplikacija, mobilna aplikacija, digitizacija, leksički podaci, korpusi, otvoreni povezani podaci
    ... in disambiguation. • X-N (6%), 2XN—a noun preceded by a word that does not inflect in the terminological phrase. Usually it is a word that is used only in one or few terminological phrases, a prefix or an adverb derived from an adjective, while the separator can be a hyphen; examples are ‘bto sistem’ ...
    ... examples, and providing a comprehensive picture of the use of terms in various dictionaries, textbooks, professional and scientific literature. A termi- nology system that includes a relational terminology database, a SPARQL endpoint with linguistic linked open data, on the one hand, and a web and mobile a ...
    ... http://vocbench.uniroma2.it (accessed on 12 February 2020). 60. Stellato, A.; Fiorelli, M.; Turbati, A.; Lorenzetti, T.; van Gemert, W.; Dechandon, D.; Laaboudi-Spoiden, C.; Gerencsér, A.; Waniart, A.; Costetchi, E.; et al. VocBench 3—A collaborative Semantic Web editor for ontologies, thesauri and lexicons ...

  • Resource-based WordNet Augmentation and Enrichment

    Ranka Stanković, Miljana Mladenović, Ivan Obradović, Marko Vitas, Cvetana Krstev (2018)
    In this paper we present an approach to support production of synsets for SerbianWordNet(SerWN)byadjustingPrincetonWordNet(PWN)synsetsusing several bilingual English-Serbian resources. PWN synset definitions were automatically translated and post-edited, if needed, while candidate literals for Serbian synsets were obtained automatically from a list of translational equivalents compiled form bilingual resources. Preliminary results obtained from a setof1248selectedPWNsynsetsshowthattheproducedSerbiansynsetscontain 4024 literals, out of which 2278 were offered by the system we present in this paper, whereas experts added the remaining 1746. Approximately one half of ...
    WordNet, bilingual resources, term alignment, parallel lists
    ... word senses, drawn from other lexicographic resources. The task provided prospective systems with a set of word senses that were not in PWN, where each word sense comprised a lemma, a part of speech, and a defi- nition. The systems were to identify the most plausible point for placing each of the word ...
    ... exception of a little over 1,000 Serbian specific synsets that do not exist in PWN. In our research we used 20,221 aligned synsets (from a previous version of SerWN), coupled with a number of bilingual resources, to speed up the development of SerWN, by selecting and adjusting PWN synsets from a set of ...
    ... TermII]* where TermI represents a word in one language, and TermII a corresponding word in another. A few examples from the en-sr parallel list are: grandmother;baka,baba soft drink;bezalkoholno piće safe,secure;bezbedan,siguran From the en-sr parallel list we produced a simple list of translation pairs ...

  • Frequency and Length of Syllables in Serbian

    Marija Radojičić, Biljana Lazić, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Ján Mačutek, Lívia Leššová (2019)
    Basic analyses of several properties of syllables (the rank-frequency distribution, the distribution of length, and the relation between length and frequency) in Serbian is presented. The syllabification algorithm used combines the maximum onset principle and the sonority hierarchy. Results indicate that syllables behave similarly to words as far as mathematical models are concerned, but values of parameters in models for syllables are quite different from those for words.
    frekvencije slogova, dužina slogova, srpski jezik
    ... rank-frequency distribution for word forms!® (cf. Popescu et al. 2009, pp. 137-138; the highest value of a is 1.6543 for a Hawaiian text, i.e. for a text written in a very analytical language). It can be a consequence of the fact that the inventory of syllables is, at least for Slavic languages, much more ...
    ... is perhaps the best known theoretical framework. A more detailed description can be found in Pulgram (1970). However, this approach requires a comprehensive dictionary that contains practically all words used in a language. Lehfeldt (1971) presented a modification, distinguishing between marginal (rarely ...
    ... distribution for word forms16 (cf. Popescu et al. 2009, pp. 137-138; the highest value of 𝑎 is 1.6543 for a Hawaiian text, i.e. for a text written in a very analytical language). It can be a consequence of the fact that the inventory of syllables is, at least for Slavic languages, much more restricted ...

  • 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

  • Bilingual lexical extraction based on word alignment for improving corpus search

    Jelena Andonovski, Branislava Šandrih, Olivera Kitanović (2019)
    Library and Information Sciences,Computer Science Applications

  • A survey of greenhouse gases production in central European lignites

    Anna Pytlak, Anna Szafranek-Nakonieczna, Weronika Goraj, Izabela Śnieżyńska, Aleksandra Krążała, Artur Banach, Ivica Ristović, Mirosław Słowakiewicz, Zofia Stępniewska (2021)
    Lignit, Gasovi sa efektom staklene bašte, Ugljen dioksid, Metan, Azotni oksid
    ... Pytlak, A., Stepniewska, Z., Kuzniar, A., Szafranek-Nakonieczna, A., Wolinska, A., Banach, A., 2014. Potential for aerobic methane oxidation in carboniferous coal measures. Geomicrobiol J. 31, 737–747. https://doi.org/10.1080/01490451.2014.889783. Pytlak, A., Sujak, A., Szafranek-Nakonieczna, A., Grzadziel ...
    ... lignite may re- duce GHG emissions from the aban- doned mines. • Detritic lignites show the potential to serve as a source of coalbed methane. G R A P H I C A L A B S T R A C T a b s t r a c ta r t i c l e i n f o Article history: Received 2 May 2021 Received in revised form 2 August 2021 Accepted ...
    ... C l o m n( n oi tc u d or p 2 ss a m yr d g 1- y a d 1- ) 0 100 200 300 400 500 a) b) Fig. 5. Greenhouse gases (GHG) production rate of CO2 (a) and CH4 (b) in the studied lignites. Mean values ± SD. Sample abbreviations as in Table 1. A. Pytlak, A. Szafranek-Nakonieczna, W. Goraj et al ...

  • A Mathematical Learning Environment Based on Serbian Language Resources

    Radojičić Marija, Obradović Ivan, Stanković Ranka, Utvić Miloć, Kaplar Sebastijan (2018)
    In recent years, in line with ever growing usage of Information technology, the learning environments are changing. The amount of available learning materials in various forms has increased. These new environments demand comprehensive learning systems, which enable management of the learning corpus with special attention paid to relevant lexical resources. In this paper we present the concept of a Mathematical Learning Environment in Serbian (MLES), which is based on a corpus of mathematical materials and various lexical resources, enabling ...
    mathematical content, text processing, mathematical formulae
    ... resources. In this paper we present the concept of a Mathematical Learning Environment in Serbian (MLES), which is based on a corpus of mathematical materials and various lexical resources, enabling semantic search of mathematical content. A specific use of the system is mathematical support in ...
    ... Bearing this in mind, development of a Mathematical Learning Environment in Serbian (MLES) has been initiated. MLES is intended as a learning environment with the main goal of processing mathematical content in Serbian. The environment built around a corpus of mathematical content and provides ...
    ... obtaining a searchable format of these materials is the conversion of source files, given specific Serbian letters. MLES provides a semantic search engine, which allows for processing of various formats of user requests, effective matching and relevance ranking, and features a user friendly ...

  • Laboratory Testing of Nanosilica- Reinforced Silicate and Polyacrylamide Gels

    Irina Zahirovic, Dušan Danilović, Milica Šuput Vranjin, Miloš Tripković (2023)
    drilling fluid formulation, upstream oil and gas, fluid dynamics, fluid loss control, gel

  • The Usage of Various Lexical Resources and Tools to Improve the Performance of Web Search Engines

    Krstev Cvetana, Stanković Ranka, Vitas Duško, Obradović Ivan (2008)
    In this paper we present how resources and tools developed within the Human Language Technology Group at the University of Belgrade can be used for tuning queries before submitting them to a web search engine. We argue that the selection of words chosen for a query, which are of paramount importance for the quality of results obtained by the query, can be substantially improved by using various lexical resources, such as morphological dictionaries and wordnets. These dictionaries enable semantic ...
    LR web services, MultiWord Expressions & Collocations, Information Extraction, Information Retrieval
    ... obtained through a query by using our approach can double and even quadruple in some cases. 1. Introduction When delivering a query to a web search engine the user is typically interested in information available on the web related to a particular topic. The result of this query is a selection ...
    ... the user, when composing a query, might omit some words related to the concept, thus reducing system recall. A simple query expansion by adding the omitted words would seemingly resolve this problem. However, the expansion of the set of words describing a concept in a query, although contributing ...
    ... probably would not even know. This is, however, the simplest conceptual expansion of a query. A more sophisticated would be a web query on Amerindian languages (amerindijanski in Serbian). The user issuing such a query is most probably not looking for the occurrences of the exact term with its ...

  • Two approaches to compilation of bilingual multi-word terminology lists from lexical resources

    Branislava Šandrih, Cvetana Krstev, Ranka Stanković (2020)
    In this paper, we present two approaches and the implemented system for bilingual terminology extraction that rely on an aligned bilingual domain corpus, a terminology extractor for a target language, and a tool for chunk alignment. The two approaches differ in the way terminology for the source language is obtained: the first relies on an existing domain terminology lexicon, while the second one uses a term extraction tool. For both approaches, four experiments were performed with two parameters being ...
    Linguistics and Language,Software,Artificial Intelligence,Language and Linguistics

  • Development of terminological resources for expert knowledge: a case study in mining

    Ljiljana Kolonja, Ranka Stanković, Ivan Obradović, Olivera Kitanović, Aleksandar Cvjetić (2015)

  • Digital Library From A Domain Of Criminalistics As A Foundation For A Forensic Text Analysis

    Dalibor Vorkapić, Aleksandra Tomašević, Miljana Mladenović, Ranka Stanković, Nikola Vulović (2017)
    U ovom radu predstavljen je model koji omogućava prikupljanje, pripremu, opis metapodataka, upravljanje i eksploataciju, uključujući pretragu punog teksta dokumenata iz domena kriminalistike napisanih na srpskom jeziku. Predloženi pristup primenjuje se na veb portalu koji sakuplja različite tekstove nastale iz časopisa Akademije za kriminalistiku i policijske studije, Krivičnog zakona Srbije, konferencija „Tara“ i „Reiss“, kao i iz nekih doktorskih disertacija vezanih za ovu oblast istraživanje. Nakon obrade teksta, korpus koji sadrži preko 5500 stranica običnog teksta, kreiran je i ...
    Omeka, Wordnet, pretraga punog teksta, morfološka i semantička pretraga teksta, proširenje upita
    ... being held in a private location" being written ahead of time. Here are some facts about suicide letters: A suicide note is typically brief, concise and highly propositional with a degree of evasiveness. A credible suicide letter must be making a definite unequivocal proposition in a situational ...
    ... ANALYSIS AS A NEXT STEP IN A STUDY OF FORENSIC TEXTS The semantic network Serbian WordNet (SWN) is a lexico-semantic resource that has been developed based on the idea of the Princeton WordNet (PWN), a mental lexicon that helps scientists working on psycholinguistic projects. SWN is a set of above ...
    ... Library From A Domain Of Criminalistics As A Foundation For A Forensic Text Analysis Dalibor Vorkapić, Aleksandra Tomašević, Miljana Mladenović, Ranka Stanković, Nikola Vulović Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Digital Library From A Domain Of ...

  • Flotability of chalcopyrite from the Rudnik deposit

    Đurica Nikšić, Predrag Lazić, Milena Kostović (2021)
    Директно селективно флотирање олова, бакра и цинка у флотацији рудника „Рудник” датира од 1984. године. Технолошка шема омогућава директно издвајање селективних концентрата у три циклуса. У првом циклусу се издваја минерал олова (галенит), док су минерал бакра (халкопирит) и минерал цинка (марматит) депримирани. У другом циклусу се оток концентрације минерала олова кондиционира и припрема за издвајање минерала бакра. Након кондиционирања, у овом циклусу се издваја минерал бакра. У трећем циклусу се оток концентрације минерала бакра кондиционира и припрема за ...
    Директно селективно флотирање, халкопирит, KAX, NaCN

  • A Model for Determining Fuzzy Evaluations of Partial Indicators of Availability for High-Capacity Continuous Systems at Coal Open Pits Using a Neuro-Fuzzy Inference System

    Miljan Gomilanović, Miloš Tanasijević, Saša Stepanović, Filip Miletić (2023)
    This paper presents a model for determining fuzzy evaluations of partial indicators of the availability of continuous systems at coal open pits using a neuro-fuzzy inference system. The system itself is a combination of fuzzy logic and artificial neural networks. The system availability is divided into partial indicators. By combining the fuzzy logic and artificial neural networks, a model is obtained that has the ability to learn and uses expert judgment for that learning. This paper deals with the ...
    системи, континуални системи експлоатације (роторни багер-транспортер-дробилично постројење), рударство, расположивост, меко рачунарство, фази логика, ANN, ANFIS