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Упит dcterms_creator_txt:Bechtel A.

1302 items

  • Cultural Heritage and Protection of Hand-Wheeled Pottery Manufacture in Western Serbia: Characteristics of Zlakusa Pottery Based on Sem-Eds and Optical Microscopy

    Milošević Maja, Zdravković Alena, Đordjević Biljana, Jelić Ivana (2021)
    ... , 2019). Sample 1 was prepared by the traditional coiling method on a hand rotated wheel, while sample 2 was made with the application of a modern mould technique. A microscopic examination of the thin sections revealed a uniform mineral composition. No significant differences were observed ...
    ... Ground mass is a clay mixture uniformly distributed with larger, mostly rounded pores, consistent with microscopical observations. Sample 2 has a fluid- like structure where both groundmass and pores have a directional appearance, consistent with previous observations, and a slightly higher ...
    ... List of the Intangible Cultural Heritage of Humanity. In technological terms, it is a unique phenomenon that actively coexists with discovery of new techniques and production processes. This brings to a rise in imitations of this pottery manufacture due to its enlarged popularity. The main ...

  • Linearization of Input Signal as a Necessary Tool in Stochastic Modeling of Karst Groundwater

    Veljko Marinović (2021)
    Modelling of karst hydrogeological systems is a very complicated task, bearing in mind that for a deterministic model one should know the internal physical processes of precipitation transformation into discharge, while for a stochastic model nonlinear dynamic systems such as karst should be simulated by linear regression equations. Stochastic models need linearization of input time series due to often large residual in the recession period. This occur because the model is not able to absorb single rain episodes, which ...
    karstne podzemne vode, stohastičko modeliranje, transfer funkcije, pokretni prosek

  • Geoheritage and Mining Heritage in the Promotion of Theme Parks: An Example of the National Park Đerdap (Carpathian-Balkan Thrust-And-Fold Belt, Eastern Serbia)

    Ivana Mojsić Velikić, Dragoman Rabrenović, Danica Srećković-Batoćanin, Darko Spahić (2022)
    The National Park Đerdap (eastern Serbia, vicinity of the Danube River) occupies a segment of the Carpathian-Balkan fold-and-thrust belt and has a significant geoheritage potential, accounting for the impressive natural (geological) and cultural legacy. In addition to the extraordinary orogenic-type landscape or nappe-stacked mountainous configura tion, the region contains evidence of ancient mining activities, uncovered within its immediate neighbourhood. The ancient mining activities date back a few thousand years ago and represent a solid ground for the idea of ...
    Karpatobalkanski pojas nabora i navlaka, Geopark Djerdap, Tematski park "Muzej rudarstva", Konzervacija, Održivi razvoj, Geotopi, Srbija

  • Development Of The Serbian Geological Resources Portal

    Ranka Stanković, Jelena Prodanović, Olivera Kitanović, Velizar Nikolić (2011)
    ... After entering a string of characters (word or part of a word), the user is offered a list of dictionary entries where the given string of characters appears, and by choosing from the list, the user can get a detailed view of the entry. Concluding remarks In this paper, we tried to give a brief presentation ...
    ... resources combined the elements of a geo-portal with classical web applications, presenting the information from diverse sources in a unified way. This paper presents technologies and tools used to develop the portal available at http://geoliss.ekoplan.gov.rs. A geo-portal is a type of web portal used to find ...
    ... development and implementa- tion of GeolISS is managed by a team from the Faculty of Mining and Geology at the University of Belgrade (FMG). Following the development of a geodatabase in ArcSDE and an ArcMap extension for data manage- ment, a web component was added to GeolISS. This web component is ...

  • Early–Middle Jurassic brachiopods from Ponor Mountain, Western Balkan Mountains, Bulgaria; taxonomy, biostratigraphy and occurrence in the context of the early Toarcian Oceanic Anoxic Event

    Barbara V. Radulović, Lubomir S. Metodiev, Neda Motchurova-Dekova, Platon Tchoumatchenco (2023)
    Brachiopods, taxonomy, biostratigraphy, early Toarcian Anoxic Event, Bulgaria

  • 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

  • Refinement of waste phosphogypsum from Prahovo, Serbia: characterization and assessment of application in civil engineering

    Josip Išek, Lazar Kaluđerović, Nikola Vuković, Maja Milošević, Ivana Vukašinović, Zorica Tomić (2020)
    γ-spectrometry, brushite, chukhrovite, phosphogypsum, radionuclides, recrystallization
    ... natural radioactive series for a period of 4 weeks. The activity concentra- tion of radionuclides was determined using a high-purity germa- nium radiation detector of 50% relative efficiency. The detector was calibrated using a secondary reference material with a char- coal matrix in the same 120 ...
    ... Accepted Manuscript online: 28 April 2020; Associate Editor: Asuman Turkmenoglu) Phosphogypsum is a waste product of the phosphoric acid manu- facturing process. It is produced in the form of a fine powder with a large calcium sulfate content. This process produces ~5 tons of phosphogypsum for every ton ...
    ... higher activity concentration of 2%U, was further subjected to the recrystallization process (Fig. 2). A total of 10 g of the sample was mixed with 2 L of distilled water in a beaker. Using a magnetic stirrer, the mixture was stirred for 2 h at ~45%C, allowed to settle for 2 h at the same tempera- ...

  • Flood protection and water utilization of karst poljes: example of Gatačko Polje, Eastern Herzegovina

    Tina Dašić, Ljiljana Vasić (2020)
    Earth-Surface Processes,Geology, Pollution, Soil Science, Water Science and Technology, Environmental Chemistry,Global and Planetary Change

  • Evaluation of the effects of wastewater heat pump integration into district heating systems by simulation

    Dejan Ivezić, Marija Živković, Dimitrije Manić, Aleksandar Madžarević, Boban Pavlović, Dušan Danilović (2023)
    The integration of wastewater heat pumps (using purified water) in district heating systems is analyzed in this paper. The simulation procedure is proposed to analyze the impacts of stochasticity of purified water temperature and flow to heat pump integration and operation. The analysis includes calculation of the daily and seasonal coefficient of performance, as well as fossil fuel savings and CO2 emission reduction due to wastewater heat pump use. The proposed procedure is implemented for the case study in ...
    otpadne vode, toplotna pumpa, daljinsko grejanje, simulacija

  • Upper Miocene depositional environments of the Kikinda-Mokrin High (Serbia)

    Saša Ivanišević, Dejan Radivojević (2018)
    Exploration for oil and gas in mature areas, such as the Pannonian Basin, can benefit from reexamination of old data using more advanced modern workflows that focus on the temporal and spatial aspects of sediment deposition. Specifically, we apply a new environment of deposition model that interprets the Upper Miocene- Pliocene sediments as being deposited in a rapidly filling basin characterized by quick shelf edge progradation from the northwest toward the southeast. Reconstruction of this shelf edge trajectory reveals ...
    naftna geologija, depozicione sredine, formacije, Panonski basen

  • Vulnerability methods in hard rock formation as a basis for groundwater risk assessment – from resource to source

    Vladimir Živanović, Igor Jemcov, Veselin Dragišić (2022)
    Groundwater in a hard rock formation is most endangered at places where a potential source can discharge contaminants that can reach the saturated zone of an aquifer. In these circumstances, an essential tool for groundwater protection is the contamination risk map. This map is based on the integration of two maps: a hazards map, i.e., map of potential sources of contamination and a vulnerability map. The selection of a proper vulnerability method is an important task since the resulting ...
    karta rizika od kontaminacije, ranjivosti podzemnih voda, DRASTIC, EPIK, PI, COP, Nacionalni park Tara

  • Lower Berriasian ammonites from Dedina (Golubac Mountains, eastern Serbia) and their biostratigraphic implication

    Zdenek Vasícek , Dragoman Rabrenović, Petr Skupien, Barbara Radulović (2023)
    Ammonites, Taxonomy, Lower Berriasian, Getic, Northern Tethys, Serbia
    ... |_f|4 Hi LI | |}- -} -_-L}] E B I J EsH|I ||BLJ-| a -B EaE E s |M | LJ |E | J E || || || A / | | j ||> |M | || }A | | || -i I L J Lj - I - - -| | - { | LJ ||_|| |A|}_| |_{L_| |f= | L J i |Epi|s | s | | 5 / % Bie|||s|P|P{E|S| ...
    ... (specimen SA13.2/12). It has a heavily corroded, flatly deformed first quarter of the last whorl and part of the third quarter of the last whorl, with a more favourable preservation of a less corroded outer mould. The unfavourably pre- served opposite side shows a small segment of development ...
    ... transitions rather abruptly into a narrow ventral side. The whorl at the base falls off with a not-very high, but clearly defined, oblique umbilical wall. The body chamber is separated from the phrag- mocone by a distinct constriction. The juvenile sculpture changes at a diameter of approximately 22 ...

  • Компарација метода XRF i ICP-MS на узорцима угља и продуктима сагоревања

    Бранко Костић, Ксенија Ераковић, Дејан Прелевић, Сабина Ковач, Драгана Животић (2023)
    геохемија, угаљ, продукти сагоревања, XRF, ICP-MS

  • Towards Semantic Interoperability: Parallel Corpora as Linked Data Incorporating Named Entity Linking

    Ranka Stanković, Milica Ikonić Nešić, Olja Perisic, Mihailo Škorić, Olivera Kitanović (2024)
    U radu se prikazuju rezultati istraživanja vezanih za pripremu paralelnih korpusa, fokusirajući se na transformaciju u RDF grafove koristeći NLP Interchange Format (NIF) za lingvističku anotaciju. Pružamo pregled paralelnog korpusa koji je korišćen u ovom studijskom slučaju, kao i proces označavanja delova govora, lematizacije i prepoznavanja imenovanih entiteta (NER). Zatim opisujemo povezivanje imenovanih entiteta (NEL), konverziju podataka u RDF, i uključivanje NIF anotacija. Proizvedene NIF datoteke su evaluirane kroz istraživanje triplestore-a korišćenjem SPARQL upita. Na kraju, razmatra se povezivanje Linked ...
    paralelni korpusi, povezivanje imenovanih entiteta, prepoznavanje imenovanih entiteta, NER, NEL, povezani podaci, NIF, Vikipodaci

  • Fuzzy optimization in hydrodynamic analysis of groundwater control systems: Case study of the pumping station “Bezdan 1”, Serbia

    Dragoljub Bajić, Dušan Polomčić (2014)
    A groundwater control system was designed to lower the water table and allow the pumping sta-tion “Bezdan 1” to be built. Based on a hydrodynamic analysis that suggested three alternative solutions, mul-ticriteria optimization was applied to select the best alternative. The fuzzy analytic hierarchy process methodwas used, based on triangular fuzzy numbers. An assessment of the various factors that influenced the selec-tion of the best alternative, as well as fuzzy optimization calculations, yielded the “weights” of the alternativesand the ...
    groundwater lowering, groundwater management scenario, fuzzy analytic hierarchy process,expert knowledge, triangular fuzzy numbers, linguistic variables
    ... modeling, in this case to define a groundwater control system for the “Bezdan 1” PS, is a common approach in modern hydrogeology. The hydrogeolog- ical setting was schematized, the input parameters defined and a model based on finite differences con- structed to develop a predictive hydrodynamic analy- ...
    ... which are a suitable verbal means of expressing the knowledge of each individual. Consequently, fuzzy logic is the codi- fication of common sense (GRAHAM 1991; LAI & HWANG 1996). Expert knowledge is used instead of differential equations to describe a system. The know- ledge is conveyed in a natural way ...
    ... knowledge in fuzzy logic is a linguistic variable, with its linguistic values that make up fuzzy sets. Combinations of variables and their values produce linguistic statements (expressions), which constitute a bridge between numerical representation of informa- tion on a computer and human thinking. ...

  • Optimisation of underground mine decline development system using genetic algorithm

    Zoran Gligorić, Aleksandar Ganić, Rade Tokalić, Aleksandar Milutinović (2014)
    ... 750 1000 1250 1500 1750 Ore body A Ore body B Ore body C UMCP SBP Ore body D MPF 40 Gligorić Z.; Ganić A.; Tokalić R.; Milutinović A. REFERENCES 1 ALI, F.A. (2014) A novel hybrid genetic differential ...
    ... access points. Brazil et al. created a software tool called Decline Optimization Toll (DOT). The heuristic methods used in DOT1 are replaced in the new version of the software tool, DOT2, by a method based on an understanding of exact solutions to a constrained 3-dimensional path problem. ...
    ... includes four ore bodies A through D with access points i = 1, 2, 3, 4 respectively. The relevant operational data are shown in Table 1 and Figure 1. 38 Gligorić Z.; Ganić A.; Tokalić R.; Milutinović A. Table ...

  • Inhibitory effect of platinum and ruthenium bipyridyl complexes on porcine pancreatic phospholipase A2

    Tina Kamčeva, Jörg Flemmig, Bojana Damnjanović, Jürgen Arnhold, Aleksandar Mijatović, Marijana Petković (2011)
    Fosfolipaza pankreasa A2 (PLA2) igra važnu ulogu u ćelijskoj homeostazi kao iu procesu karcinogeneze. Efekti metalo-lekova koji se koriste kao hemoterapeutici na aktivnost ovog enzima nisu poznati. U ovom radu, interakcija između PLA2 svinjskog pankreasa i dva odabrana kompleksa prelaznih metala — tetrahloro(bipiridin) platine(IV) ([PtCl4(bipi)]) i dihloro (bipiridin) rutenijum(III)hlorida ([RuCl2(bipi)2) ]Cl)—proučavana je. Laserska desorpcija/jonizacija uz pomoć matriksa, vremenska masa spektrometrija (MALDI-TOF MS) i fluorescentna spektroskopija korišćeni su za analizu aktivnosti enzima u odsustvu i prisustvu metalnih kompleksa i za ...
    Metals and Alloys, Biochemistry, Biomaterials, Biophysics, Chemistry (miscellaneous)
    ... W. Duncan, G. Matanovic and A. Cerpa-Poljak, Rapid Commun. Mass Spectrom., 1993, 7, 1090–1094. 43 D. C. Muddiman, A. I. Gusev, A. Proctor, D. M. Hercules, R. Venkataraman and W. Diven, Anal. Chem., 1994, 66, 2362–2368. 44 D. C. Muddiman, A. I. Gusev, K. Stoppeklangner, A. Proctor, D. M. Hercules, P ...
    ... formation of arachidonic acid and derived biomediators, this enzyme displays a critical role in cellular homeostasis due to catalysis of a rate- limiting step. Accordingly, it has been shown that pancreatic PLA2 plays a role in carcinogenesis, immune suppression, stimulation of cell proliferation ...
    ... shown that human pancreatic PLA2 stimulates the growth of a human pancreatic cancer cell line via binding to a specific receptor.9,14 It also stimulates extracellular matrix invasion by normal and cancer cells.15 In addition, this enzyme is a target protein for triggered liposomal drug delivery to ...

  • Geoenvironmental Investigations at a Smelter Location in Bor (Serbia)

    Petar Papić, Zvonimir Milijić, Jana Stojković, Jovana Milosavljević, Maja Todorović, Marina Ćuk, Željko Kamberović (2014)

  • 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
    ... sufficient quantities [11]. Energy security is a parameter whose specificity lies in the influence of many factors, so it is not possible to define a unique methodology to determine [12]. Defining a methodological approach for determining the energy security of a country is possible only if the geopolitical ...
    ... It is also called a pessimistic composition due to the procedure by which it is performed—the presentation of a synthetic grade using a representative partial grade, which is defined as the best possible among the worst expected individual grades [48,49]; • Min–max composition is a fuzzy composition ...
    ... economy of a scenario. It is directly linked to national structures (institutions and human resources) [36], as well as the legal framework that follows relevant issues. The security of supply is a synthesis indicator that can be viewed in a very broad context. It is generally defined using a set of s ...

  • Improving efficiency of thermal power plants through mine coal quality planning and control

    Mirjana Banković, Dejan Stevanović, Milica Pešić, Aleksandra Tomašević, Ljiljana Kolonja (2018)
    Главни циљ контроле квалитета угља у рудницима лигнита је снабдевање термоелектрана угљем чији квалитет мора да се креће унутар одређених квалитативних ограничења. Карактеристике угља могу да утичу на ефикасност, поузданост и расположивост како котла тако и јединица за контролу емисије. У овом раду аутори су презентовали интегрисану симулацију рударског процеса као нови приступ у истраживању променљивости калоричне вредности угља приликом експлоатације комплексног лежишта лигнита. Резултати таквог приступа омогућавају драгоцен увид у перформансе континуалног рударског система у смислу контроле променљивости ...
    mine planning, variability of coal quality, simulation, coal blending