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Упит dcterms_subject_txt:Global and Planetary Change

2342 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
    ... facts and heuristics which can be represented by means of rules, frames, semantic networks and other formalisms. Since knowledge is the key factor in problem solution and decision making, the quality and usability of an expert system is basically determined by the accuracy and completeness ...
    ... developed at the Faculty of Mining and Geology of the University of Belgrade (Lilić, Stanković, and Obradović, 1994). This package, which enables the simulation of air flow distribution in a mine, the heat and fire transmission mechanisms, distribution of gas and distribution of respirable mineral ...
    ... KAPPA-PC Object Browser for VENTEX The classes and objects of the modified OOA model shown in /Fig. 1/ were transformed to classes and instances in the KAPPA-PC system. Thus the classes and object from /Fig. 1/ are represented by KAPPA-PC classes and instance as shown in the system’s object browser ...

  • Polyhedral characteristics of the cosalite-type crystal structures

    Sabina Kovač, Predrag Dabić, Aleksandar Kremenović, Aleksandar Pačevski, Ljiljana Karanović, Marko V. Rodić, Martina Tribus (2019)
    kristalna struktura, kozalit, poliedarske karakteristike

  • Using Query Expansion for Cross-Lingual Mathematical Terminology Extraction

    Velislava Stoykova, Ranka Stanković (2018)

  • Development of integrated fuzzy model for mine management optimization

    Miodrag Čelebić, Sanja Bajić, Dragoljub Bajić, Dejan Stevanović, Duško Torbica, Vladimir Malbašić (2023)
    fuzzy logika, višekriterijumsko odlučivanje, ocenjivanje eksperata
    ... Ko – safe and healthy work environment, Ky - extractable ore reserves, and K+ — coefficient of ore de- pletion. The considered mining: technology options, based on the natural setting, included: Ai — block caving, Ao — sublevel caving, A3 — cutting and filling, and Aa – room and pillar mining ...
    ... inherent uncertainties, vagueness, and inaccuracies. As a result, subjective evaluation by engineers and expert experience have become increas- ingly important. Given that the natural language used by miners and geologists is most suited for relaying: knowledge and expressing; opinions, the paper ...
    ... underlying: and overlying, limestones. The underlying limestones are solid homo- geneous rocks, with numerous fractures and a number of fault zones. Expert experience suggested potential problems for certain types of mining. operations. Additionally, also based on experience and the physical and mechanical ...

  • Evaluation And Perspectives Of Underground Coal Mines In Serbia

    Vladimir Milisavljević, Milena Lekić, Ivica Ristović, Vojin Čokorilo, Aleksandar Cvjetić (2017)
    ... roof and floor conditions, rock pressure and geo-mechanic conditions (criteria C2); • Mining hazards, such as gas, water, dust and potential for gas outbursts and spontaneous combustion (criteria C3); • Potential for mechanization, such as seam inclination, seam thickness, floor and roof ...
    ... facilities and supply facilities (criteria C4); • Quality of coal and products, such as coal type, sulphur content, ash content, moisture content, calorific value and amount of fines (criteria C5); • Market and delivery possibilities, such as current markets served, the distance to the market and transport ...
    ... (Soko, Strmosten pit in REMBAS mine, Lubnica and Štavalj) and for closure of those mines without potential (Tadenje and Jarando pits of Ibarski mines, Senjski rudnik pit of REMBAS, Bogovina and Vrška Čuka). This approach leaves Jasenovac mine and Block IV pit of REMBAS mine in between these two ...

  • E-Connecting Balkan Languages

    Cvetana Krstev, Ranka Stanković, Duško Vitas, Svetla Koeva (2009)
    In this paper we present a versatile language processing tool that can be successfully used for many Balkan languages. This tool relies for its work on several sophisticated textual and lexical resources that were developed for most of Balkan languages. These resources are based on several de facto standards in natural language processing.
    Query expansion, e-dictionary, wordnet, proper name, aligned text
    ... etc.) and its derivatives. For instance, if meronymy relation is established between concepts ‘New York’ and ‘United States of America’, then their Serbian Latin equivalents Njujork and Sjedinjene Američke Države, Serbian Cyrillic equivalents Њујорк and Сједињене Америчке Државе, and Bulgarian ...
    ... these tools was until now used only for Serbian, and in bilingual context, for Serbian and English. In this paper we will show that tools WS4LR and WS4QE are truly independent both from Serbian, for which they were initially developed, and from English which seems to be in the background ...
    ... prove the usability of WS4LR and WS4QE for languages other then Serbian and English we used various resources, both textual and lexical. In the following sections we will briefly present these resources, what methodological framework was used for their development, and how they were integrated ...

  • 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

  • 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
    ... ‘onion’ and one for the compound as whole which takes care of agreement conditions. These transducers expand the query beli luk into beli luk AND belim lukom AND beli lukovi AND belih lukova AND belima lukovima AND belim lukovima AND bele lukove AND bela luka AND beloga luka AND belog luka ...
    ... language ć, č, š ,ž ,đ, dž, lj and nj, are internally coded as cx, cy, sx, zx, dx, dy, lx and nx, respectively) 222 Figure 2. Semantic expansion of a query The query, now composed of two Latin and two Cyrillic strings was then submitted by WS4QE to Google and, as a result, a total of 92 ...
    ... Faculty of Mining and Geology, Belgrade 3 professor, Faculty of Mathematics, Belgrade, 4 professor, Faculty of Mining and Geology, Belgrade E-mail: cvetana@matf.bg.ac.yu, ranka@rgf.bg.ac.yu, vitas@matf.bg.ac.yu, ivano@rgf.bg.ac.yu Abstract In this paper we present how resources and tools developed ...

  • 2D geoelectrical resistivity tomography application at the former city waste dump "Ada Huja": Eco-geological problem

    Branislav Sretenović, Filip Arnaut, Ivana Vasiljević, Vesna Cvetkov (2019)
    2D inversion, geoelectrical method, Wenner array, ecology, Ada Huja
    ... ranks in the top three causes of repulsive odor just behind methyl-sulfide and ethyl- acetate (Yue et al., 2012). Gases that contribute to global warming cannot be forgotten, they predominantly consist of carbon-dioxide and carbon-monoxide. Alongside methane which makes up 45-60% of the total emitted ...
    ... highly flammable and it is a side effect of every landfill especially the ones that are not regulated by the state (safely secured). Not sanitizing the methane released from a landfill will inevitably lead to its release into the atmosphere. Methane has a 23 times higher global warming index than ...
    ... carbon-dioxide and hydrogen. The last phase is methane production by methanogenic bacteria which either dissolve those acids into methane and carbon-dioxide or reduce carbon-dioxide with hydrogen (Themelis and Ulloa, 2006). Looking at the research done by the Environmental and Energy Study Institute ...

  • New data on the age of an Upper Cretaceous clastic-carbonate succession in Brežđe (Western Serbia)

    Nevenka Đerić, Nataša Gerzina (2014)
    Gornja kreda, radiolarije, Jadar blok, zapadni pojas Vardarske zone, zapadna Srbija
    ... housed at the Faculty of Mining and Geology in Belgrade (registration numbers BR 1/1, BR 1/2 and BR 1/3). 4.SECTION DESCRIPTION AND BIOSTRATIGRAPHY Inthe wider area of Brežđe, MARKOVIĆ & ANĐELKOVIĆ (1953) distinguished Albian-Cenomanian, Cenomanian, Turo- nian and Senonian sediments. According ...
    ... G, 1996). 5. DISCUSSION AND CONCLUSIONS After the Late Jurassic obduction and subsequent erosion in the Dinaridic-Hellenic belt, Cretaceous synorogenic basins were formed and filled with clastic material composed of variable amounts of ophiolitic, terrigenous and carbonate detritus (LUŽA ...
    ... sediments - ggr“gngg mćlange and Miocene dacite Cretaceous sediments - gg:)%()szigc and Triassic Paleozoic granite <= snnistal strike-slip fault == Dextal strike-slip fault —— Pre-Senonian thrust — — Post-Senonian thrust — 7Majorsyncline = Major anticline Figure 2:A simplified and modifted geological ...

  • Simulation of Hydrogeological Environmental Discharge in Case of Interruption Constant Observations

    Marina Čokorilo Ilić, Dragoljub Bajić, Miroslav Popović (2024)
    Monitoring Network, data, hydrogeological environment, tunnel, simulation

  • Towards Automatic Definition Extraction for Serbian

    Ranka Stanković, Cvetana Krstev, Rada Stijović, Mirjana Gočanin, Mihailo Škorić (2021)
    U radu su prikazani preliminarni rezultati automatske ekstrakcije kandidata za definicije rečnika iz nestrukturiranih tekstova na srpskom jeziku u cilju ubrzanja razvoja rečnika. Definicije u rečniku Srpske akademije nauka i umetnosti (SANU) korišćene su za modelovanje različitih tipova definicija (opisnih, gramatičkih, referentnih i sinonimskih) koje imaju različite sintaksičke i leksičke karakteristike. Korpus istraživanja sastoji se od 61.213 definicija imenica, koje su analizirane korišćenjem morfoloških e-rečnika i lokalnih gramatika implementiranih kao pretvarači konačnih stanja u paketu za obradu korpusa otvorenog ...
    ... dictionaries and previous research into Serbian (Krstev et al. 2015). 3 Analysis and Recognition of Definitions in the SASA Dictionary The first step in our research was a thorough analysis of various lexical and syntactic features of definitions in the Serbian Academy of Sciences and Arts (SASA) ...
    ... Krstev 2012). Finite state transducers are visualized by graphs for easier development and use. A local grammar and its corresponding graph that models (and recognizes) definitions of nouns that represent attributes and/or state is given in Figure 1. Below the graph, six definitions are listed that are ...
    ... of 25 primary and secondary school textbook covering the following domains: biology, history, logic, music, computer science, physics and design and technology (technological education). The biology domain is covered by seven textbooks: one for primary school, four for high school, and two for agricultural ...

  • Spatial distribution of major and trace elements in artificial lakes in Serbia: health risk indices and suitability of water for drinking and irrigation purposes

    Goran Marković, Aleksandar Ž. Kostić, Nebojša Đ. Pantelić, Radojka Maletić, Jana Štrbački, Jovan Cakić, Lazar Kaluđerović, Biljana P. Dojčinović, Angelo Maria Giuffrè, Jelena B. Popović-Djordjević (2023)
    Lakes and reservoirs are the main water resources for household, irrigation, and industrial use. Hence, it is necessary to control water pollution and have reliable information on water quality, which refers to its suitability for a particular purpose. The main objective of this study was to evaluate the suitability of water for drinking and irrigation purposes from ten artificial lakes on the territory of the Republic of Serbia. The physicochemical parameters were determined using standard analytical methods, whereas the ...
    Management, Monitoring, Policy and Law, Pollution, General Environmental Science, General Medicine

  • 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
    ... shows mapping between UD_POS and N_POS tags. In most cases it is one-to-one relation but there are some differences between tagsets. N_POS doesn’t differentiate between VERB and AUX, CCONJ and SCONJ, NOUN and PROPN. On the other hand, it separates SENT from PUNCT and PREF from X. The most frequent ...
    ... Krstev, and D. Vitas “Lexical Analysis of Serbian with Conditional Random Fields and Large-Coverage Finite-State Resources”, Proc. 7th Language and Technology Conference (LTC), Poznan, Poland, Nov. 2015 [8] N. Ljubešić, F. Klubička, Ž. Agić, and I. Jazbec, “New inflectional lexicons and training ...
    ... Šandrih, C. Krstev, M. Utvić, and M. Škorić, “Machine Learning and Deep Neural Network-Based Lemmatization and Morphosyntactic Tagging for Serbian,” Proc. International Conference on Language Resources and Evaluation, pp. 3954‑3962, May 2020 [24] A. Akbik, D. Blythe, and R. Vollgraf, “Contextual String ...

  • Some models for determination of parameters of the soil oscillation law during blasting operations

    Suzana Lutovac, Dragan Medenica, Branko Gluščević, Rade Tokalić, Čedomir Beljić (2018)
    ... explosive amount, and conditions of blasting and geologic characteristics of the soil; all of this being determined on the basis of test blasting for the specific work environment. In the Sadovskii equation two parameters, K and n appear and they are conditioned both by rock mass characteristics and blasting ...
    ... blast site to the monitoring point (m); r0—radius of the explosive charge; and n—exponent, conditioned by soil properties and mining conditions and determined by field measurements as well. The radius of the explosive charge r0 and the amount of explosive Q are related by the equation: Q “ 4 3 ¨ π ¨ r3 ...
    ... reduced distances for models 1, 2 and 3. The survey of reduced distances R, recorded oscillation velocities vr, calculated oscillation velocities vi1, vi2, and vi3, as well as the difference between the recorded and calculated soil oscillation velocities for models 1, 2, and 3, are presented in Table 2. ...

  • Structural characterization of traditional pottery produced from local clay, Rujište (Ražanj, Central Serbia), in an effort to preserve its geoheritage

    Maja Milošević, Biljana Đorđević, Alena Zdravković (2021)
    ... a mixture. As some of the slabs have rolled and rough edges they may be regarded as illite and/or halloysite. Morphology varies from short tubular, spheroidal and elongated tubules, which are the most common. EDS data confirmed hydroxides of illite and iron. Illite minerals deposited from formation ...
    ... Management and Events Ltd., Sofia Printing House: Bulged, Sofia 1505 Editors: Ruslan I. Kostov, Radostina Atanassova ISBN 978-954-92875-6-1 © Earth and Man National Museum, 2021 © Bulgarian Mineralogical Society, 2021 9th International Conference Mineralogy and Museums ...
    ... clay body based on mineralogy and applying the obtained knowledge in the preservation of this type of intangible cultural heritage, inscribed in the National register of ICH and as geoheritage in Serbia as well. The analysis of the phase, mineral composition and structure of the clay body was ...

  • Rift sequence stratigraphy and its contribution to source rock understanding – Serbian part of Pannonian Basin

    Filip Anđelković, Dejan Radivojević (2018)
    ... simple shear exten- sional mechanism (Matenco and Radivojević, 2012). The analysis of syn-kinematic reflectors demonstrates that normal faulting migrates in time and space and took place on a wide Miocene time interval (roughly 20–5.5 Ma) (Matenco and Radivojević, 2012). The most prolific source rocks ...
    ... (Eds). The Carpathians and their foreland: geology and hydrocarbon resources, AAPG Memoir 84, 619–632. Matenco, L. Radivojević, D. 2012. On the formation and evolution of the Pannonian Basin: Constraints derived from the structure of the junction area between the Carpathians and Dinarides. Tectonics ...
    ... rocks in Serbian part of Pannonian Basin are marls and limestones of the Sarmatian and Pannonian (Kostić, 2012). Besides this sequence, source rocks are also to a lesser extent rep- resented by shales of the Badenian and Pre-Badenian Tertiary, while the Lower Pontian shales were found to contain only ...

  • Crystal structure of K3EuSi2O7

    Sabina Kovač, Predrag Dabić, Aleksandar Kremenović (2021)
    alkalni silikati elemenata retkih zemalja, kristalna struktura, sinteza metodom fluksa, rendgenska difrakcija na monokristalu
    ... space group P63/mcm and is isostructural with disilicates K3ErSi2O7 15 and K3YbSi2O7. 22 The crystal structure is comparable to the sorosilicate structure type reported earlier by Vidican and co-authors.13 The crystal structure of the title compound consists of Si2O7 groups and EuO6 polyhedra which ...
    ... code: Eu atoms and polyhedra are grey, Si atoms are dark grey and O atoms are white. Fig. 3. Projection of structure along [120] showing two types of regularly alternating layers, which are parallel to the (001) plane: (I) octahedral layers and (II) sorosilicate layers. K atoms and polyhedra are ...
    ... black, Eu atoms and polyhedra are grey, SiO4 polyhedra are dark grey and O atoms are white. OnLin e Fir st 6 KOVAČ et al. The structure is characterized by two crystallographically distinct six- coordinated sites occupied by Eu1 and Eu2: Eu1O6 is an octahedron (OC-6) and Eu2O6 is a trigonal ...

  • 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- ...