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Упит dcterms_subject_txt:Hierarchical cluster analysis

750 items

  • Simulacija isticanja odabranih karstnih vrela pirotske kotline

    Saša Milanović, Branislav Petrović, Vesna Ristić Vakanjac, Ljiljana Vasić, Veljko Marinović, Petar Vojnović (2022)
    Analiza recesije, autokorelaciona i kroskorelaciona analiza vremenskih serija padavina i isticanja podzemnih voda karstnih vrela Krupac i Gradište (Stara planina, JI Srbija) izvršena je radi formiranja stohastičkog autoregresivno-krosregresivnog modela (ARCR) i kratkoročne prognoze dnevnih vrednosti izdašnosti. Usled postojanja heterogenosti i anizotropnosti karstne izdani veoma je komplikovano i zahtevno odrediti prostornu distribuciju podzemnih voda u okviru karstnog hidrogeološkog sistema, te je primenljivost determinističkih modela minimizirana. Stoga je upotreba stohastičkog modela u ovom slučaju svrsishodnija. Autokorelogram izdašnosti vrela Krupac pokazao je ...
    karstno vrelo, recesija, autokorelacija, kroskorelacija, ARCR MA model, JI Srbija

  • Regionalna karakterizacija karstnih podzemnih voda dela centralnog Balkana u funkciji njihovog održivog korišćenja i menadžmenta

    Veljko J. Marinović (2022)
    Karstne podzemne vode koristi oko 700 miliona ljudi na svetu, čime je njihov značaj za svetsko stanovništvo nemerljiv. U sklopu doktorske disertacije vršena su istraživanja i analize karstnih sistema dela centralnog Balkana (Srbije, Crne Gore i Savskog sliva Bosne i Hercegovine), kako bi se evaluirao ovaj dragoceni resurs. Analize su vršene na primerima karstnih sistema vrela Perućac, Seljašnica, Mokra i Mlava (Srbija), Oko Bijele i Rijeka Crnojevića (Crna Gora) i vrelo Bosne (Bosna i Hercegovina), kao i na regionalnom ...
    karstni sistem, podzemna voda, pritisci na kvantitet i kvalitet, menadžment podzemnih vodnih resursa

  • Epidotized sanidine in quartzlatites from Grot

    Danica Srećković-Batoćanin, Suzana Erić, Nikola Novičić, Nikola Pašajlić, Natalija Batoćanin (2023)
    Propilitska alteracija je veoma česta u gornjokredno-tercijarnim vulkanitima Srbije. Kvarclatiti Grota, otkriveni na dubini od oko 550 m u jednoj od istražnih bušotina su holokristalaste porfirske strukture sa fenokristalima sanidina dimenzija i do 1,5 x 2 cm. Optičkim ispitivanjima su u kvarclatitu potvrdjeni i elementi sitaste, pojkilitske i glomeroporfirske strukture. Kao fenokristali prisutni su sanidin, plagioklas, kvarc, biotit i amfiboli. Sekundarni minerali su hlorit, epidot, coisit, Fe-hidroksidi, redak kalcit i ilit. U fenokristalima sanidina se zapažaju „lepeze“ izduženih kristala ...
    Grot, kvarc latiti, sanidin, epidot

  • Hydrothermal Synthesized and Alkaline Activated Carbons Prepared from Glucose and Fructose—Detailed Characterization and Testing in Heavy Metals and Methylene Blue Removal

    Sanja Krstić, Milan Kragović, Maja Pagnacco, Vladimir Dodevski, Branka Kaluđerović, Miloš Momčilović, Ivica Ristović, Marija Stojmenović (2018)
    glukoza, fruktoza, аktivni ugalj, hidrotermalni tretman, aktivacija hidroksida, teški metali, metilen plavo
    ... treatment. After preparation, samples were characterized in details. Different techniques were used: x-ray powder diffraction analysis, Raman spectral analysis, elemental analysis, and determination of textural and morphological properties. Obtained results showed dependence of investigated properties and ...
    ... treatment. After preparation, samples were characterized in details. Different techniques were used: x-ray powder diffraction analysis, Raman spectral analysis, elemental analysis, and determination of textural and morphological properties. Obtained results showed dependence of investigated properties and ...
    ... 3.1.2. Elemental Analysis The contents of organic C, N, O and H in glucose and fructose samples obtained after hydrothermal treatment and activation with different hydroxides were determined by elemental analysis and the results are listed in Table 1. Table 1. Elemental analysis of the glucose and ...

  • Asbestos-Based Pottery from Corsica: The First Fiber-Reinforced Ceramic Matrix Composite

    Philippe Colomban, Aleksandar Kremenović (2020)
    Asbestos-containing pottery shards collected in the northeast of Corsica (Cap Corse) and dating from the 19th century, or earlier, have been analyzed by SEM-EDS, XRPD, FTIR and Raman microspectroscopy. Blue (crocidolite) and white (chrysotile) asbestos fiber bundles are observed in cross-sections. Most of the asbestos is partly or totally dehydroxylated, and some transformation to forsterite is observed to occur, indicative of a firing above 800 C. Examination of freshly fractured pieces shows a nonbrittle fracture with fiber pull-out, consistent with ...
    asbestos, CMC, Corsica, fiber, pottery
    ... surfaces and cross-sections were observed with an optical microscope (BX51 Microscope, Olympus Corporation, Tokyo, Japan). Raman microspectroscopic analysis was performed using, two instruments: (i) a high-resolution HR800 LabRam spectrometer (Horiba Scientific Jobin Yvon, Longjumeau, France) coupled ...
    ... Jobin Yvon, Lille, France) spectrometer equipped with YAG 532 nm and He 633 nm lasers and a similarly cooled CCD detector (resolution ~4 cm !). The analysis was carried out with Olympus x10, x50 and x100 ultralong, working distance objectives in order to obtain a characterization of the main phases ...
    ... acceleration voltage of 20 kV. The sample was wrapped with carbon-rich tape with a small window for the area to be studied. Quantitative elemental analysis (oxide) was conducted done using, the ZAF calculation method as implemented in the Iridium Ultra software (IXRF Systems, Austin, TX, USA). The ...

  • Determination of the groundwater-leakage mechanism (binary mixing) in a karstic dam site using thermometry and isotope approach (HPP Visegrad, Bosnia, and Herzegovina)

    Ljiljana Vasić, Saša Milanović, Anita Puskás-Preszner, Laszlo Palcsu (2020)
    Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry, Global and Planetary Change

  • New approach to correlation of hydrocarbon reservoirs in sandstone layers of the "Mokrin" field"

    Saša Ivanišević, Dejan Radivojević (2018)
    геофизички каротаж, депозиционе средине, лежишта угљоводоника, миоцен, пост‐ рифтнo, секвенциона стратиграфија
    ...  the quantitative  interpretation  of well‐log curves and the analysis of geological data from nine wells: KM‐117, 17, 1, 2, 3, 4, 5, 6 and 7  (Figure 1а and 1b). The principles of sequence stratigraphy have been applied in the analysis of geophy‐ sical  and  geological  data, while  the  correlation  ...
    ... ls.   Reconstruction of depositional environments  and correlation of lithostratigraphic units (Figure 1a and 1b) have been executed based on the analysis  of the shape and characteristics of curves of gamma ray  (GR) and specific resistivity  (RT)  logs.   Funnel  shape of  the GR  log points  to  the  ...
    ... ial” correlation, hydrocarbon  reservoirs  of  the  “Mokrin”  field  represent  individual  sandstone  layers.  The  new  approach,  using  the  analysis of geological and geophysical data according to the principles of sequence stratigraphy, with the  focus on definition of depositional environments ...

  • Influence of paleoenvironmental conditions on distribution and relative abundance of saturated and aromatic hydrocarbons in sediments from the NW part of the Toplica basin, Serbia

    Nikola Burazer, Aleksandra Šajnović, Nebojša Vasić, Milica Kašanin-Grubin, Dragana Životić, João Graciano Mendonça Filho, Predrag Vulić, Branimir Jovančićević (2020)
    Stratigraphy,Economic Geology,Geology,Geophysics,Oceanography

  • Projecting short to medium-term effects of carbon emissions trading on Serbia's GDP

    Boban Pavlović, Nikola Trtica (2024)
    This paper presents an approach to assess the short to medium-term effects of the Emissions Trading System (ETS), an economic and climate policy instrument aimed at reducing greenhouse gas emissions, on GDP from the expenditure side. The analysis focuses on Serbia’s electricity sector, which relies heavily on lignite-based pro duction dominated by state-owned enterprises. The obtained projections suggest that in the short term, the introduction of an ETS may lead to slower GDP growth compared to official forecasts. However, ...
    ETS, BDP - rashodni pristup, cene električne energije
    ... of an ETS on GDP is that the analysis may seem somewhat straightfor- ward, as it focuses mainly on key parameters and assumes that certain variables remain relatively constant according to official projections. This constraint can limit the depth of the analysis and may not capture the full ...
    ... results serve as a solid foundation for a comprehensive analysis. CRediT authorship contribution statement B. Pavlović: Writing – original draft, Visualization, Investigation, Conceptualization. N. Trtica: Methodology, Investigation, Formal analysis. Declaration of competing interest The authors ...
    ... Trading System (ETS), an economic and climate policy instrument aimed at reducing greenhouse gas emissions, on GDP from the expenditure side. The analysis focuses on Serbia's electricity sector, which relies heavily on lignite-based pro- duction dominated by state-owned enterprises. The obtained p ...

  • Microstructural and magnetic properties of electrospun hematite/cuprospinel composites

    Mira Ristić, Aleksandar Kremenović, Michael Reissner, Željka Petrović, Svetozar Musić (2020)
    Phase composition, microstructural and magnetic properties of electrospun hematite/cuprospinel composites were investigated. Samples were synthesized starting with 0 to 10 mol% of copper relative to iron. The round shape of reference electrospun fbres was preserved upon their heating up to 600 °C in air, whereas at 700 °C hollow substructure was additionally formed. In these reference samples the presence of hematite phase was detected by XRPD. A small amount (traces) of Fe3O4 /γ-Fe2O3 was also found, due to the ...
    Electrical and Electronic Engineering, Condensed Matter Physics, Atomic and Molecular Physics and Optics, Electronic, Optical and Magnetic Materials

  • Classification of Terms on a Positive-Negative Feelings Polarity Scale Based on Emoticons

    Mihailo Škorić (2017)
    The goal of this paper is to draw attention to the possibility of using emoticon-riddled text on the web in language-neutral sentiment analysis. It introduces several innovations in the existing framework of research and tests their effectiveness. It also presents a software tool especially made for that purpose, explains how it builds a database with sentimental value of terms and offers the user manual. Finally, it presents a software tool that tests the new database and gives some examples ...
    data mining, information extraction, emotions, text on the web
    ... according to the mood that is expressed in them to help find the necessary information. – Natural language understanding and analysis: understanding of written text and text queries, analysis of moods in the text, processing of digital linguistic resources such as automatic parallelization and automation of ...
    ... ABSTRACT: The goal of this paper is to draw attention to the possibility of using emoticon-riddled text on the web in language- neutral sentiment analysis. It introduces sev- eral innovations in the existing framework of research and tests their effectiveness. It also presents a software tool especially ...
    ... sentimental value of terms and offers the user manual. Finally, it presents a software tool that tests the new database and gives some examples of the analysis of the ob- tained results. KEYWORDS: data mining, information extraction, emotions, text on the web. PAPER SUBMITTED: 24 January 2017 PAPER ACCEPTED: ...

  • Freeze-dried nanocrystal dispersion of novel deuterated pyrazoloquinolinone ligand (DK-I-56-1): Process parameters and lyoprotectant selection through the stability study

    Jelena R. Mitrović, Maja Bjelošević Žiberna, Aleksandar Vukadinović, Daniel E. Knutson, Dishary Sharmin, Aleksandar Kremenović, Pegi Ahlin Grabnar, Odon Planinšek, Dominique Lunter, James M. Cook, Miroslav M. Savić, Snežana D. Savić (2023)
    Recently, nanocrystal dispersions have been considered as a promising formulation strategy to improve the bioavailability of the deuterated pyrazoloquinolinone ligand DK-I-56-1 (7‑methoxy-2-(4‑methoxy-d3-phenyl)-2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one). In the current study, the freeze-drying process (formulation and process parameters) was investigated to improve the storage stability of the previously developed formulation. Different combinations of lyoprotectant (sucrose or trehalose) and bulking agent (mannitol) were varied while formulations were freeze-dried under two conditions (primary drying at -10 or -45 °C). The obtained lyophilizates were characterized in terms ...
    Pharmaceutical Science
    ... mean + standard deviation. Statistical analysis included Student t-test (for two sets of results) or one-way ANOVA (for three sets of results) with Tukey HSD as a post hoc test. P values < 0.05 were considered as statistically significant. Statistical analysis was done using IBM SPSS Statistics ...
    ... extend shelf-life more than threefold compared to the liquid state formulation published in Mitrović et al. (2020). 3.3. Physical state analysis Analysis of the physical state of the freeze-dried formulations included differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD) ...
    ... et al., 2014). Informa- tion about hydrogen bonding can be inferred from analysis of the po- sition and width of the OH-stretching band in the FT-IR spectrum (Sritham and Gunasekaran, 2017). In this study, the analysis included the interpretation of the transmission spectra of bulk excipients ...

  • Long-term rockslope monitoring and rockfall prediction

    Miloš Marjanović, Biljana Abolmasov, Marko Pejić, Jelka Krušić (2021)

  • Prezentacija projekta "Zaštita ležišta mineralnih sirovina kao osnova sigurnog snabdevanja mineralnim sirovinama u Evropi (safemin4europe)

    Vladimir Simić, Rade Jelenković, Dragana Životić, Zoran Miladinović, Stefan Petrović, Marija Petrović (2022)
    Harmonični ekonomski razvoj svake zemlje u velikoj meri zavisi od dostupnosti sirovina, naročito mineralnih sirovina. Obezbeđivanje njihove dovoljne količine na tržištu (ponude) je od vitalnog značaja za funkcionisanje različitih industrijskih grana koje proizvode različitu robu i opremu neophodnu za ispunjavanje životnih potreba stanovništva kao i za efikasnu poljoprivredu. Mineralne sirovine su neophodne za podršku ekonomskim aktivnostima na lokalnom, regionalnom, nacionalnom i međunarodnom nivou. Ovo su, istorijski, prve sirovine koje su počele da se koriste iz domaćih izvora, i u ...
    ležišta mineralnih sirovina, valorizacija, zaštićena područja, socijalni aspekti

  • Komparacija metoda XRF i ICP-MS na uzorcima uglja i produkata sagorevanja

    Branko Kostić, Dejan Prelević, Sabina Kovač, Ksenija Eraković, Dragana Životić (2022)
    Ugljevi niskog ranga – ligniti u Republici Srbiji predstavljaju glavnu energetsku sirovinu koja se koristi za proizvodnju električne energije. Rudarstvo u Srbiji doprinosi bruto dodatoj vrednosti sa 1,8% (2020; https://publikacije.stat.gov.rs/). Sagorevanjem ugljeva niskog ranga u termoelektranama generišu se velike količine elektrofilterskog pepela i pepela, koje često predstavljaju jedan od izvora zagađenja životne sredine usled sadržaja toksičnih elemenata. Dalja upotreba produkata sagorevanja zavisi od njihovog sastava i sadržaja toksičnih mikroelemenata. Svakodnevno sagorevanje lignita u termoelektranama uslovljava konstantan monitoring potencijalno toksičnih ...
    ugalj, produkti sagorevanja, XRF, ICP-MS

  • Geotehnički efekti razaranja komunalnog otpada različitim postupcima zbijanja

    Jovana M. Janković Pantić (2022)
    Odlaganje otpada na komunalne deponije predstavlja osnovni način zbrinjavanja otpada u Srbiji. Kako bi se prostor za deponovanje materijala racionalno koristio potrebno ga je svakodnevno zbijati sa unapred definisanom količinom vode koja se dodaje. Dobro zbijeni komunalni otpad zauzima manju zapreminu i omogućuje sigurnije skladištenje, pa je korisno prethodno laboratorijski odrediti parametre zbijanja: maksimalnu suvu zapreminsku težinu (dmax) i optimalnu vlažnost (wopt). U Srbiji do sada nisu određivani parametri zbijanja, dok je u svetu primenjivana standardna metoda (Proktorov opit) ...
    komunalna deponija, zbijanje, Proktorov opit, malj sa šiljcima, koeficijent razaranja

  • Assessments of effects of implementation of strategic plans for development of Belgrade District heating system

    Dejan Ivezić, Marija Živković, Aleksandar Madžarević, Miodrag Grujić (2020)
    The district heating system (DHS) is one of the key elements of the Belgrade energy system. Overview of the current state and basic characteristics of the DHS are presented in this paper. The focus is on the planned development of DHS and on the analyses of effects of realization of measures and projects defined by strategic documents related to DHS which are adopted by city authorities (Development Strategy of DHS and Strategy of Belgrade Development). Two exploratory scenarios were ...
    Daljinsko grejanje, LEAP, Primarni energetski faktor, Uvozna zavisnost, CO2 emisija

  • Determination of Mechanical Properties of Altered Dacite by Laboratory Methods

    Veljko Rupar, Vladimir Čebašek, Vladimir Milisavljević, Dejan Stevanović, Nikola Živanović (2021)
    This paper presents a methodology for determining the uniaxial and triaxial compressive strength of heterogeneous material composed of dacite (D) and altered dacite (AD). A zone of gradual transition from altered dacite to dacite was observed in the rock mass. The mechanical properties of the rock material in that zone were determined by laboratory tests of composite samples that consisted of rock material discs. However, the functional dependence on the strength parameter alteration of the rock material (UCS, intact ...
    Geology, Geotechnical Engineering, Engineering Geology
    ... for different participation of AD. Minerals 2021, 11, 813 12 of 19 Also, the analysis included relationships between shear and normal stresses that were constructed based on the Mohr circles of stress. This analysis determined the envelopes for all analyzed participation of altered dacite, which ...
    ... strength σci on the participation of altered dacite (AD%) based on the analysis of laboratory test results is shown in Figure 13. An exponential and linear function Minerals 2021, 11, 813 13 of 19 approximates the analysis results shown in the diagram (Figure 13), and the dependence σci TX—AD% ...
    ... assessing rock mass input parameters necessary for geotechnical stability analysis and detailed design solutions. Author Contributions: Conceptualization, V.R.; methodology, V.R. and V.Č.; validation, V.M., D.S. and N.Ž.; formal analysis, V.R. and V.Č.; investigation, V.R., V.Č., V.M., D.S. and N.Ž.; resources ...

  • The external aggregation Newton's method for solving nonlinear equations and applications

    Marija Paunović, Dejan Ćebić, Nebojša Ralević (2020)
    Њутнов метод, агрегациона функција, ред конвергенције

  • Fuzzy Model for Risk Assessment of Machinery Failures

    Dejan V. Petrović, Miloš Tanasijević, Saša Stojadinović, Jelena Ivaz, Pavle Stojković (2020)
    The main goal of this research was the development of an algorithm for the implementation of negative risk parameters in a synthesis model for a risk level assessment for a specific machine used in the mining industry. Fuzzy sets and fuzzy logic theory, in combination with statistical methods, were applied to analyze the time picture state of the observed machine. Fuzzy logic is presented through fuzzy proposition and a fuzzy composition module. Using these tools, the symmetric position of the ...
    fazi teorija, rizik, otkaz rudarskih mašina
    ... based on fuzzy logic conclusion and min–max composition. The main advantage of the developed model is that it evaluates the risk levels of higher hierarchical structures based on an elemental risk assessment. The presented model can be generally used for other machines as well. The rest of the paper ...
    ... possibility of acting in order to prevent or minimize the consequences of a failure. The second step is to determine the level of risk for higher hierarchical structures on the basis of risk level assessment for the elements (components). In order to analyze the risk indicators for component failure ...
    ... specific fuzzy set (minor, low, moderate, high, or very high), happens through defuzzification. The process of defuzzification can be applied to all hierarchical levels of an engineering system, depending on the assessment requirements. 3.1. Fuzzy Proposition Fuzzy proposition is a process of defining ...