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Упит dcterms_subject_txt:Statistical and Nonlinear Physics

2340 items

  • NMR kinetic studies of the interactions between [Ru(terpy)(bipy)(H2O)]2+ and some sulfur-donor ligands

    Aleksandar Mijatović, Biljana Šmit, Ana Rilak, Biljana Petrović, Dragan Čanović, Živadin D. Bugarčić (2012)
    Reakcije supstitucije monofunkcionalnog [Ru(terpi)(bipi)(H2O)]2+ kompleksa, gde je terpi = 2,2′:6′,2″-terpiridin i bipi = 2,2′-bipiridin, sa biološki relevantnim sumporo donorskim ligandima, kao što su tiourea, l-metionin, l-cistein i glutation, proučavane su u vodenim rastvorima tehnikom 1H i 13C NMR spektroskopije. Sve reakcije su proučavajne na pH 7,4, u prisustvu fosfatnog pufera, da bi se oponašalo fiziološko okruženje tokom procesa supstitucije. Reakcije se izvode na 295 K pod uslovima reakcija drugog reda. Uočeni rezultati pokazuju da brzina supstitucije snažno zavisi ...
    Materials Chemistry,Inorganic Chemistry,Physical and Theoretical Chemistry

  • The influence of alkyl polyglucosides (and highly ethoxylated alcohol boosters) on the phase behavior of a water/toluene/technical alkyl polyethoxylate microemulsion system

    Marija Ilic, Franz-Hubert Haegel, Vesna Pavelkic, Dragan Zlatanovic, Snezana Nikolic-Mandic, Aleksandar Lolic, Zoran Nedic (2016)
    The influence of additives (alkyl polyglucoside, Glucopon 600 CS UP and alcohol ethoxylate C18E100) on the behavior of the water/toluene/Lutensol ON 50 (technical oxoalcohol, i-C10E5) microemulsion system as a function of temperature and composition has been investigated. The phase behavior of the microemulsions was determined by vertical sections through the Gibbs phase prism (fish-like phase diagrams). Alkyl polyglucoside shifts the one phase region to lower temperatures compared with water/toluene/Lutensol ON 50 mixtures. This is contrary to the expectation, considering ...
    микроемулзија, толуен, алкил полиглукозид, оксоалкохол етоксилат, појачивач ефикасности, „fish“ дијаграми
    ... RESULTS AND DISCUSSION The pseudo-binary phase diagrams of micro- emulsion systems were determined at equal mass fractions of water and toluene (a= 0.5) for two non- ionic surfactants, pure linear CxjEs and technical branched i-Cxo5Es (Lutensol ON 50) in order to find the composition and temperature ...
    ... exists consisting of a middle-phase microemulsion in equilibrium with excess phases of oil and water, surrounded by two-phase regions illustrated as 20 and 20 . When a surfactant is mainly dissolved in water and two phases consist of a surfactant-rich water (lower) phase in equilibrium with an excess ...
    ... surfactant needed to solubilize water and oil and is a measure for the efficiency of the surfactant. The corresponding temperature, f, is a measure for the phase inversion temperature (//7). The phase diagrams were recorded by success- ively adding water and oil to the initial water-oil-surf- ...

  • Non-Detonating Chemical Mixture for Non-Invasive Methods of Rock Breaking

    Lazar Kričak, Milanka Negovanović, Nikola Simić, Stefan Milanović (2024)
    Within the Innovation developed several different non-detonating chemical mixtures for non-invasive methods of rock breaking. Laboratory and polygon tests gave the satisfactory results and knowledge enough to start the practical experiments in the field. The basis of this innovation is a theoretical assumption that certain chemical mixtures release a large quantity of gases during combustion. If these gases are found in the enclosed space a growing pressure on the walls of the chamber in which combustion takes place will ...
    non-detonating, chemical mixture, rock breaking, borehole pressure

  • 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

  • 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
    ... Mining and Geology, Đušina 7, 11000 Belgrade, Serbia, e-mail: btrivic@rgf.bg.ac.rs 3 Faculty of Mining and Geology, Đušina 7, 11000 Belgrade, Serbia, e-mail: ranka@rgf.bg.ac.rs 4 Faculty of Mining and Geology, Đušina 7, 11000 Belgrade, Serbia, e-mail: olja@rgf.bg.ac.rs 5 Faculty of Mining and Geology ...
    ... implement field data records and measurements i.e. the basis for classified features, interpretations and models. Any observed property can be expressed as a text, number, picture and geometry (location). Spatial entities are treated as observation localities and mapped/interpreted geologic entities ...
    ... references and persons involved and responsible for data acquisition. Metadata also include essential information’s about project, for which the data are to be collected. For data entry in GeolISS database designed special ArcGIS extension was designed and implemented in MS Visual Studio and ArcObject ...

  • Mine ventilation system planning using genetic algorithms

    Nikola Lilić, Ranka Stanković, Ivan Obradović (1997)
    The most common problem in contemporary mining practice related to the planning and analysis of ventilation systems is the optimization of partially regulated air distribution in mine ventilation networks. This paper presents a two step optimization procedure for partly regulated air distribution in mine ventilation networks. The first step is the determination of air distribution in all branches using the well known Hardy-Cross method. In the second step the distribution and parameters of air flow regulators with minimum engaged ...
    coal, lignite, and peat; ventilation systems; coal mining; underground mining; ventilation; mathematical models; design; air flow; optimization; calculation methods

  • 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

  • The Fuzzy–AHP Synthesis Model for Energy Security Assessment of the Serbian Natural Gas Sector

    Aleksandar R. Madžarević, Dejan D. Ivezić, Miloš L. Tanasijević, Marija A. Živković (2020)
    Natural gas is used for the production of almost 20% of total energy today. The natural gas security of the Republic of Serbia is an urgent strategic, political and security issue. Serbia is one of the most vulnerable countries in Southeast Europe, because it only has one supply route. This study is a contribution to efforts to better understand the factors affecting energy security through the implementation of a new methodology based on the fuzzy–AHP synthesis model for measuring ...
    energetska bezbednost, prirodni gas, fazi AHP, AHP višekriterijumska analiza, fazi teorija
    ... provides discussions; and finally Section 7 draws conclusions. 2. The Fuzzy–AHP Synthesis Model for Energy Development Scenarios During the procedure, data collection is performed, which can be statistical (based on calculation, software model result, projections, statistical processing, etc.) or based ...
    ... Author Contributions: Conceptualization, A.R.M. and D.D.I.; methodology, M.L.T. and A.R.M.; supervision, M.A.Ž. and D.D.I.; validation, D.D.I. and M.A.Ž.; formal analysis and writing—original draft A.R.M.; investigation, A.R.M. and M.L.T. All authors have read and agreed to the published version of the manuscript ...
    ... operate with numerical and linguistic data and universality of application. The result of the proposed model shows a quantified assessment of energy security and its trend in the future of the natural gas sector. It indicates an unacceptably low level of present energy security and a gas system very vulnerable ...

  • Softverski alati za korišćenje resursa za srpski jezik

    Ivan Obradović, Ranka Stanković (2008)
    ... dictionaries and aligned texts, can be further refined and used for different purposes, by means of tools specially developed for these tasks. The tools we describe are WS4LR, a software tool that has already been developed and used for solving different tasks within the Group, and a web application ...
    ... encompassed by WS4LR and WS4QE, namely the system of mor- phological dictionaries of Serbian, the Serbian wordnet and aligned texts. 2.1 Morphological dictionaries Morphological dictionaries of simple and compound words for Serbian have been devel- oped within the Group by C. Krstev and D. Vitas for many ...
    ... words (Vitas and Krstev, 2005). 3 WS4LR – a tool for maintenance and integrated use of lexical resources With the growth of the number of resources as well as their volume and content, a need emerged for the development of software tools which would alleviate their maintenance, use and inte- gration ...

  • From post-disaster landslides inventory to open landslides data

    Biljana Abolmasov, Miloš Marjanović, Uroš Đurić, Jelka Krušić (2021)

  • Post Early Miocenevertical-axis clockwise rotation in the West Vardar Zone of Serbia

    Vesna Lesić, Emo Marton, Vesna Cvetkov, Dragana Jovanović (2018)
    ... which can be drawn out from ourresults are that the overall-mean directions and their statistical errors for the Late Cretaceous sedimentlocalities and Oligocene-Earliest Mioceneigneous sites from the Rudnik Mts. area and the Oligocene igneouslocalities/sites from the Kopaonik Mts. area indicate uniform ...
    ... for linear segments which were used for statistical evaluation on locality/site level. The fold/tilt test was carried out on locality (when applicable) and regionallevel. The obtained results show that the remanent magnetization both in the igneous rocks and sediments resides in magnetite. The locality ...
    ... Faculty ofMining and Geology, Department ofGeophysics, Djusina 7, 11000 Belgrade, Serbia The Vardar-Tethyan mega-suture lies between the Eurasian and Gondwana margins. It is composed of remnants of obducted ophiolites and ophiolite mćlange, distal parts of adjacent continental margins and post-obduction ...

  • Simple 2D Gravity-density inversion for modeling of the sedimentary basin basement

    Ivana Vasiljević, Snežana Ignjatović, Dragana Đurić, (2019)

  • Building Terminological Resources in an e-Learning Environment

    Ranka Stanković, Ivan Obradović, Olivera Kitanović, Ljiljana Kolonja (2012)
    ... experimental phase we developed yet another glossary of statistical terms within the subject Informatics 2. When this glossary is concerned, we found it more practical to proceeded in a somewhat different manner, placing both the Serbian and English equivalents within the same entry. An example of ...
    ... from RudOnto is used for labeling and annotation of cartographic content both in Serbian and English. Such annotation is enabled by the existing relations between Serbian and English translational equivalents, and by the strict relation between the dictionary and the content of the database. Some ...
    ... process, and it is included in the blended learning approach at the Faculty of Mining and Geology through an export of its subsets to the Moodle e-learning environment. This paper gives an outline of RudOnto, details about Moodle implementation on the Faculty of Mining and Geology, and describes ...

  • Analysis and visualization of geophysical well-logging data from closely spaced boreholes

    Branislav Sretković, Ivana Vasiljević, Dimitry Sidorov - Biryukov (2024)
    Geophysical logging measurements for determining the condition of the rock mass on the dam profile and locating the predisposed directions of water circulation and loss from the reservoir were conducted in four boreholes distributed at a close distance. The survey was carried out in a typical karst terrain, which is an additional challenge for defining the geological model, especially in terms of water retention. That kind of data set provides an excellent opportunity for a new approach to analysis ...
    well-logging in karst, water loss, data correlation, data fusion
    ... opportunity for a new approach to analysis and visualization that differs from the standard logging data processing. Numerical interpolation and correlation of data from various logging measurements (short-normal and long-normal resistivity, spontaneous potential and gamma ray logging), proved to be a ...
    ... s of karst in terms of surface and underground water circulation, as well as stability and hazard assessment for large objects such as dams (Sretković and Vučković, 2020). 'The use of geophysical characterization of karst systems can provide an economical and non-invasive alternative _ for ...
    ... for a new approach to analysis and visualization that differs from the standard logging data · processing. Numerical interpolation and correlation of data from various logging: measurements (short-normal and long-normal rresistivity, | spontaneous potential and gamma ray logging), proved to ...

  • Data from the Digital Repository of the Faculty of Mining and Geology in eScience (eNauka)

    Biljana Rujević, Mihailo Škorić (2024)
    The paper describes linking the Digital Repository of the University of Belgrade, Faculty of Mining and Geology, with the eScience system in terms of transferring metadata about the results of researchers' scientific work. The steps taken to ensure a smooth harvesting of metadata are outlined. Additionally, a presentation of additional improvements to the OAI system is provided, aiming to contribute to the automatic linking of authors with their results in the eScience system.
    репозиторијуми, еНаука, метаподаци, Рударско-геолошки факултет

  • Valorization of non-balanced coal reserves in Serbia for underground coal gasification

    David Petrović, Lazar Kričak, Milanka Negovanović, Stefan Milanović, Jovan Marković, Nikola Simić, Ljubisav Stamenić (2019)
    In the name of a better and safer energy future, it is our responsibility to focus our knowledge and activities to save on imported liquid and gas fossil fuels, as well as coal on which energy security of Serbia is based. The rationalization in the use of available energy resources certainly positively affects economy and the environment of a country. This paper indicates motivations for the application of the underground coal gasification process, as well as surface gasification for ...
    ugalj, gasifikacija, zaštita životne sredine, skladištenje, solarna
    ... activated, and the coke burns the surrounding coal and forms the reaction zone. Exothermic reactions (at f > 600 "C) are predominantly occurring in UCG process, and the resulting gas mixture can contain 8-20% CO», 5-20% CO, 10-20% H», and 2-5% CHoa. Ifthe gas mixture contains too much CO., and possibly ...
    ... from the gas mixture of UCG, and its possible storage carbon capture and storage, depends on the technological development of the separation and storage of CO [3]. Syngas can be used to produce a number of usable products, such as electricity, liquid fuels and chemical raw materials. The com ...
    ... bar and — capacity up to 4000 mš of gas/h. And for the gas parameters are: — quantity of produced gas up to 100000 mž of gas/h, — gas pressure 0.2 bar, and — gas temperature 200-400 *C. Air, Oxygen, Steam CO,CO, H„ CH, |- —— Oxidation zone. —— j- Reduction zone +| -- Drying and Pyrolysis ...

  • Analysis of the exhaust emissions inventory from auxiliary mining machines

    Stevan Đenadić, Aleksandar Mirković, Jovana Mitrović, Filip Miletić, Predrag Jovančić, Dragan Ignjatović (2023)
    Open-pit coal mines are equipped with a large number of mining machines and vehicles with diesel engines. Due to common daily operation of these machines and vehicles large amounts of exhaust gases which contain numerous pollutants are emitted into the atmosphere. The demand to reduce air pollution induced the activities in developed countries to map and calculate all gases emitted by industries to formulate and select adequate preventive activities. In collaboration with machine manufacturers, emission standards for off-road machines ...
    emissions, mining, auxiliary machines

  • Effectiveness Analysis of Different Bucket-wheel Excavators

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Miloš Tanasijević, Filip Miletić (2021)
    Coal production in open-pit lignite mines in the Republic of Serbia is performed with continuous work systems. In addition to coal production, the same systems are used for the exploitation of large quantities of overburden. According to the reliability concept, continuous systems are in linear connection. If the failure occurs in one part of the system, that will produce a downtime of the entire system. The initial and most important factor of continuous systems is the bucket-wheel excavator. It ...
    bucket-wheel excavator, open-pit coal mine, mining, multi-criteria decision methods

  • The optimization of auxiliary machinery in open-cast lignite mines: a case study of bulldozers

    Dragan Ignjatović, Predrag Jovančić, Stevan Đenadić, Ivan Janković, Ivica Ristović (2019)
    One of the most important prerequisites for the successful operation of the open-cast lignite mine is to carry out all the auxiliary works timely with the necessary quality. The most important and most commonly used auxiliary machines are bulldozers. Engaging time of bulldozers use is in direct relation with the coefficients of the time and capacity utilization of the continuous system for the excavation of coal and tailings, which indicates their importance. More than 100 bulldozers have been hired ...
    open-cast coal mine, auxiliary works, bulldozers, optimization, availability
    ... selection, including savings and improvements, can be achieved by these activities: In-time replacement of auxiliary machines and vehicles; Usage of proven and quality machines with implemented unification as much as possible; Improvement of maintenance system; Implement modern and improved technologies ...
    ... reduce the operational and maintenance costs, increase the volume of auxiliary works and create conditions for maximal utilization of Excavator — Conveyor — Stacker and Excavator — Conveyor — Crusher systems. In another word, these activities will increase time utilization and production rate utilization ...
    ... Efficiency and Occupational Safety” (TR 33039), “Developed new methods for diagnosis and examination mechanical structures” (TR 35040) and a part of the project “Research on possibility for AT (Advanced Technology) rockbolting application in mines for the purpose of increasing work safety and production ...

  • Fluid inclusion systematics in the Okoška gora polymetallic deposit

    Aleš Šoster, Miloš Velojić, Barbara Potočnik Krajnc, Matej Dolenec (2021)
    ... conditions. In addition, the S2 and Q2 inclusions follow the growth zonesofthe crystals, indicating the simultaneouscrystal growth and fluid nclusion entrapement. Conversely, thc itregular, needle-like, and ameboid inclusions ofQ1 and S1 occur in linear, subparallel structures and have a higher proportion ...
    ... whereas the gangueis primarily quartz, sericite and adularia. The predominantminera! style is stockwork breccia with open-space veins and abundantdruse-lined cavities fill terminated crystals of gangue and ore minerals. Ore disseminations are minor and. restricted to pyrite. Ore minerals have not been ...
    ... resort (Mihael Ravnjak, verbal comm.). The timing and genetic conditi Okoška Gora deposit have bcen hotly debated (Droveniket al., 1980 and references t with metamorphosed and intrusion-related hydrothermal models proposed. Berce argued for a hydrothermalorigin ofthe deposit associated with emplacement of ...