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Упит dcterms_subject_txt:geoelectrical method

551 items

  • VENTEX: An Expert System for Mine Ventilation Systems Analysis

    Ranka Stanković, Nikola Lilić, Ivan Obradović (1996)
    Analiza sistema za ventilaciju je komleksan proces, koji bazira na proračunu brojnih parametara, koji se odnose na: stanje mreže, provetrenost, stabilnost sistema, gubitke vazduha, klimatske uslove, gasno stanje, ugroženost od požara i opasne prašine. Navedeni problemi se uspešno rešavaju paketom SimVent, ali potpuno razumevanje i korišćenje dobijenih rezultata zahteva angažovanje iskusnog specijaliste iz oblasti ventilacije. Rešenje je nađeno u kreiranju ekspertnog sistema VENTEX, čija je baza znanja formalizacija ekspertskog znanja iz oblasti ventilacije rudnika. U radu je prikazana metodologija ...
    ekspertni sistem, ventilacija

  • 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

  • Geostatički proračuni sanacije klizišta šipovima

    Slobodan Ćorić, Dragoslav Rakić, Dušan Berisavljević (2019)
    U ovom radu su, polazeći od rezultata geotehničkih istraživanja, prikazani geostatički proračuni sanacije klizišta vertikalnim šipovima. Metodologija proračuna je složena, jer podrazumeva interakciju klizišta i stabilizirajućih šipova. Stoga se simultano analiziraju stabilnost klizišta i stabilnost šipova. Prilikom određivanja bočne otpornosti tla oko šipova koristi se metoda Brinč Hansena koja uzima u obzir trodimenzionalne uslove u tlu i može da se primeni u složenim geološkim uslovima koji su česti u Srbiji. Analize stabilnosti klizišta vrše se odgovarajućim metodama granične ravnoteže. ...
    sanacija klizišta, interakcija klizišta i šipa, bočna otpornost šipova, stabilnost klizišta i šipova

  • Analysis of a simplified model for determining rock mass oscillation velocity at the Kovilovača open pit

    Suzana Lutovac, Miloš Gligorić, Jelena Majstorović, Luka Crnogorac (2023)
    ... models, using the values obtained by experimental measurements [6]. Model 1 – Determining the parameters by applying the least square method. The Least Square Method is mainly used to obtain the parameters K and n which represents a common model. Model 2 — Determining the parameters through the ...
    ... velocity equation defines velocity alteration of rock mass oscillation depending on distance, explosive amount, properties of rock material and blasting method. The equation, defined in this way, offers the possibility to determine the seismic effect of blasting towards a structure, whereby the connection ...
    ... elastic waves C, = 2852.67[m/ s] ; = 62.46[GN/m2], • dynamic elasticity modulus FE„ lin • „dynamic Poisson' ratio //„„ — 0.39|iGN/m2] . 6.2 Method of blasting in the open pit Kovilovača Measurements of seismic shocks in the open pit Kovilovača were performed during blasting, conducted for the ...

  • 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

  • Control of substructure construction of railways in the Republic of Serbia

    Dragan Lukić, Dragoslav Rakić, Irena Basarić Ikodinović (2022)
    Контрола збијености природног тла (у ископу) или збијеног у насипу при изградњи саобраћајница представља један од основних облика контроле квалитета доњег строја. Код изградње брзих саобраћајница (аутопутеви и брза железница) приоритет је постизање високог нивоа контроле извршених радова. У циљу онемогућавања диференцијалног слегања (при изградњи насипа), или промене запремине услед допунског збијања материјала, које неминовно доводе до деформација, потребно је извршити оптимално збијање материјала. У оквиру овог рада приказује се техничка регулатива која регулише контролу збијености при изградњи железничке ...
    доњи строј, техничка регулатива, насип, збијеност, контрола
    ... European countries, as follows: In 2006, Instructions 338 were adopted for the control of compaction of the substructure of railway tracks by the dynamic method with a light falling weight (Light Weight Deflectometer) device on the JŽ railway network. In 2012, the Regulations on the design of reconstruction ...
    ... often lead to the degradation of the substructure, which results in the need to repair and reduce the speed. It is an indisputable fact that this test method is used as faster one in the world, but it is carried out with other tests: determination of Dpr, water content, correlation relations Ev2/Ev1, c ...
    ... Ev2 and Evd, determination of degree of unevenness, coefficient of water resistance (for protective layer) . In the Republic of Serbia, this test method is not yet standardized (so the ASTME 2835 standard is used) and can be applied only in correlation with standardized methods. According to the provisions ...

  • Synthesis and characterization of high-pressure and high-temperature sphene (CaTiSiO5)

    Jelena Pantić, Vladimir Urbanovich, Vesna Poharc-Logar, Bojan Jokić, Marija Stojmenović, Aleksandar Kremenović, Branko Matović (2014)
    Sphene (CaTiSiO5), a calcium titanosilicate ceramic has been prepared from a powder mixture of CaCO3, TiO2 and SiO2 using vibro-milling for homogenization and activation of precursors. During the highpressure and high-temperature synthesis (HPS) process at 4 GPa and 1,200 °C, sphene undergoes into phase transition, from room-temperature phase P21/a to high-temperature phase A2/a. Evidence of that structural phase transition is given in this paper using infrared, Raman spectroscopy and X-ray powder diffraction. Rietveld refinement was employed to get the ...
    Sphene, Phase transition, Raman spectroscopy, X-ray diffraction, SEM, IR

  • Mineral and Thermal Waters of Serbia: Multivariate Statistical Approach to Hydrochemical Characterization

    Maja Todorović, Jana Štrbački, Marina Ćuk, Jakov Andrijašević, Jovana Šišović, Petar Papić (2016)
    ... ement concentrations in the groundwater samples were measured using high reso- lution inductively-coupled plasma mass spectrometry (HR ICP–MS). The method to determine gross alpha/beta activities was based on the evapora- tion of 3 L of the water sample under UV lamps and calcining at 550 °C to a con- ...
    ... groundwater samples. In this study, hierarchical cluster analysis (HCA) was applied using Statistica version 6.1. Cluster analysis is a multivariate method which aims to classify a set of observations, e.g. groundwa- ter samples, on the basis of the extent of similarity of their physical and chemical ...
    ... differences in their physical and chemical characteristics. This hierarchical clustering was developed using a combination of the Ward’s linkage method (Ward 1963) and squared Euclidean distance (Massart and Kauf- man 1983), as a measure of similarity between samples. It was concluded that the ...

  • Characterization of biochar surface functional groups

    Marija Ilić, Vesna Pavelkić, Aleksandar Lolić, Branko Leković (2021)
    In this work, biochar originating from paper fibres was examined. Biochar was prepared via pyrolysis method at 550°C. Oxygen-containing functional groups on biochar surface were determined. The surface functional groups of biochar were analysed by Fourier transform infrared spectroscopy. The amount of oxygen-containing functional groups was performed with Boehm titration. The total acidity of biochar was mostly attributed to carboxylic and lactonic groups.
    biochar, surface functional groups, spectroscopy

  • Overcoming the Low Oral Bioavailability of Deuterated Pyrazoloquinolinone Ligand DK-I-60-3 by Nanonization: A Knowledge-Based Approach

    Jelena R. Mitrović , Branka Divović-Matović, Daniel E. Knutson, Jelena B. Ðoković, Aleksandar Kremenović, Vladimir D. Dobričić, Danijela V. Randjelović, Ivana Pantelić, James M. Cook, Miroslav M. Savić, Snežana D. Savić (2021)
    Poor water solubility of new chemical entities is considered as one of the main obstacles in drug development, as it usually leads to low bioavailability after administration. To overcome these problems, the selection of the appropriate formulation technology needs to be based on the physicochemical properties of the drug and introduced in the early stages of drug research. One example of the new potential drug substance with poor solubility is DK-I-60-3, deuterated pyrazoloquinolinone, designed for the treatment of various neuropsychiatric ...
    pyrazoloquinolinones, nanocrystals, wet media milling, fasted/fed bioavailability

  • Indeksi kontrole održavanja i korišćenja rotornog bagera

    Jovana Mitrović, Predrag Jovančić, Dragan Ignjatović, Stevan Đenadić, Filip Miletić (2023)
    Razvoj površinske eksploatacije se u velikom stepenu zasniva na svestranoj mehanizaciji rudarskih radova. Kako bi se zadovoljili potrebni kapaciteti, neophodna je primena savremene mehanizacije, velikih kapaciteta i pouzdanosti u radu. Naime, sa stepenom povećanja mehanizovanosti radova smanjuje se broj zaposlenih radnika, povećava produktivnost rada, smanjuju troškovi po jedinici proizvoda, a samim tim i povećava ekonomičnost površinske eksploatacije. Predmet istraživanja su rotorni bageri SRs 1200 koji predstavljaju samohodne mašine kontinuiranog dejstva namenjene za otkopavanje jalovine i korisne supstance na površinskim ...
    rudarstvo, rotorni bager, indeksi održavanja, indeksi korišćenja, TOPSIS

  • Primena termografije u rudarstvu

    Stevan Đenadić, Vesna Damnjanović, Predrag Jovančić, Dragan Ignjatović, Dragutin Jovković, Filip Miletić (2019)
    Danas, gotovo da nema oblasti u nauci i tehnici u kojoj se Infracrvena termografija ne primenjuje kao metoda za lociranje i praćenje zagrejanih objekata ili tela, beskontaktnu procenu temperature površina, i nedestruktivno ispitivanje materijala. U radu su prikazane mogućnosti i perspektive primene ove metode u oblasti rudarstva.
    infracrvena termografija, rudarstvo, monitoring

  • Geotechnical Conditions for Construction of Savski Trg Metro Station as a Part of the Belgrade Metro Line One

    Nemanja Stanić, Dragoslav Rakić, Josip Isek, Slavoljub Simić (2024)
    In order to solve serious traffic congestion in Belgrade, a number of studies regarding the Belgrade Metro construction have been carried out since 1973. However, only in 2019, the routes of the future metro lines 1 and 2 were defined as a part of the General Metro Construction Project. The lines are designed to intersect at the location of Sava Square, where an interchange metro station will be built. It represents a complex geotechnical structure consisting of three different ...
    metro station, geotechnical modelling, displacements

  • Trans-Lithospheric Diapirism as a Possible Mechanism for Ophiolite Emplacement?

    Nikola Stanković, Taras Gerya, Vladica Cvetković, Vesna Cvetkov (2024)

  • Synthesis, characterization and photocatalytic examination of Co0.9Ho0.1MoO4 nanopowders

    Milena Rosić, Maja Milošević, Maria Čebela, Vladimir Dodevski, Vesna Lojpur, Radomir Ljupković, Aleksandra Zarubica (2023)
    ... electron microscopy (FESEM), and nitrogen adsorption method. The photocatalytic activity of acquired Cop.Hop , MoO, nanopowders was estimated by the photocatalytic degradation of crystal violet in aqueous solution. A simple and effective . method for controlling: the composition and morphology of ...

  • Numerical modelling of the roughly simultaneous emplacement of two distinct ophiolite belts

    Nikola Stanković, Vesna Cvetkov, Vladica Cvetković (2024)

  • Cytotoxic activity of tetradentate Schiff Base Copper(II) complexes

    Nevenka Gligorijević, Aleksandar Mijatović, Sandra Aranđelović, Rada Baošić (2021)
    Istraživanje kompleksa bakra kao potencijalnih antikancerogenih agenasa nudi ohrabrujuće perspektive u odnosu na komplekse platine (II) računajući na smanjenu toksičnost, novi mehanizam delovanja, različit spektar aktivnosti i perspektivu neunakrsne rezistencije. Kompleksi Šifovih baza bakra(II) koji sadrže tetradentatne ligande acac2en tipa (acac2en (1); tfacac2en (3), acactfacacen (4), acacphacacen (6)) pokazali su važnu antioksidativnu aktivnost, visok potencijal za interakciju sa HSA i DNK, u prethodnim studijama. Zbog toga je bilo interesantno ispitati i uporediti potencijal antikancerogene aktivnosti in vitro, u odnosu ...
    Bakar(II) kompleksi, citotoksičnost, ćelijski ciklus
    ... breast adenocarcinoma MCF-7, colon adenocarcinoma LS-174 and normal fibroblast cells-MRC-5 and examined effect on cell cycle progression. Material and method: Time and dose dependent cytotoxicity was determined for 48 and 72 h continual treatment, using MTT assay. Further potential of investigated copper ...
    ... adenocarcinoma MCF-7, colon adenocarcinoma LS-174 and normal fibroblast cells-MRC-5 and examined effect on cell cycle progression. Material and method: Time and dose dependent cytotoxicity was determined for 48 and 72 h continual treatment, using MTT assay. Further potential of investigated copper ...

  • Temperature induced evolution of nanostructured Ni0.9Zn0.1O

    Kremenović Aleksandar, Antić Bratislav, Vučinić-Vasić Milica, Colomban Philippe, Jovalekić Čedomir, Bibić Nataša, Kahlenberg Volker, Leoni Matteo (2010)
    The crystal structure and microstructure of as-prepared and annealed Ni0.9Zn0.1O were refined at room temperature in both the Fm (3) over barm and R (3) over barm space groups. It is shown that below the Neel point (458 K), where magnetic ordering triggers the presence of a trigonal strain, the common usage of a higher-symmetry non-admissible space group for crystal structure and microstructure analysis via the Rietveld method may result in both an incorrect structure description and incorrect microstructure ...

  • 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

  • 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
    ... – These use sound waves to measure flow. There are two main methods: a.Doppler method - Measures changes in the frequency of the sound wave caused by the movement of particles in the fluid. b.Transit-time method - Measures the time it takes for the sound wave to travel between two sensors, which ...
    ... dataset through sampling. There are two basic approaches: 1.Undersampling: In this method, only samples from the majority class are used to achieve a balance with the minority classes. 2.Oversampling: This method adds copies of examples from the minority class to achieve balance between classes ...
    ... examples from the minority classes to achieve a more balanced data distribution. Additionally, there is a method for generating synthetic samples to reduce class imbalance. One popular method is SMOTE (Synthetic Minority ' Over-sampling Technique), which creates synthetic samples from the minority ...