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Упит dcterms_subject_txt:Izvozni tornjevi,Jugoslovenski standardi

497 items

  • Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete

    Milan Kragović, Nenad Ristić , Jelena Gulicovski, Andrijana Nedeljković, Snežana Pašalić, Ivica Ristović, Marija Stojmenović (2021)
    sagorevanje lignita, otpadna šljaka, zamena cementa, proizvodnja maltera i betona, fizičko-mehanička i fizičko-hemijska karakterizacija
    ... accordance with standard EN 12350-2 and was determined using the Abrams cone slump method. The density of fresh concrete was determined according to standard EN 12350-6, in a metal, cylindrical vessel with a capacity of 8 dm3. Air content in fresh concrete was determined according to standard EN 12350-7 ...
    ... with the standard EN 1015-3. For the testing, a metal conical mold was used, with a lower base diameter of 100 mm. The mean value of the mortar slump in two orthogonal directions on the flow table represented the test result. The bulk density of fresh mortar was determined according to standard EN 1015-3 ...
    ... The density of hardened concrete (water-saturated) was determined according to standard EN 12390-7 on the samples shaped like cubes with a side length of 150 mm. Flexural strength was determined in accordance with standard EN 12390-5 and testing was conducted on the prisms 400 mm in length, with a square ...

  • Characterization and Environmental Evaluation of Recycled Aggregates from Construction and Demolition Waste in Belgrade City Area (Serbia)

    Filip Abramović, Miroslav Popović, Vladimir Simić, Vesna Matović, Radmila Šerović (2024)
    General Materials Science

  • Coal homogenization stockyard sizing “Tamnava – Zapad” case study

    Božo Kolonja, Dinko Knežević, Ranka Stanković, Dejan Stevanović, Detlef Trummer (2016)
    ... statistical methods - through standard deviation. When quality is assessed based on lower heating value, the acceptable range for a power plant, as the end user, is considered to be ±500 kJ/kg [Ignjatović et al, 2007, Stevanović et al, 2015]. By observing the standard deviation, a diagram can be plotted ...
    ... range of the observed parameter. Figure 1 shows a standard deviation diagram for lignite from the "Tamnava – Zapad" pit [Knežević et al, 2014], where the x-axis shows the number of layers in a pile (package), while the y-axis shows the standard deviation for LHV, and the narrow gray lines show the ...
    ... stacking the requisite number of layers. The number of layers, stacking method, size and number of piles in the stockyard are selected by applying standard deviation as a statistical decision-making method. This paper presents considerations relating to coal stockyard sizing at the "Tamnava - Zapad" ...

  • Određivanje zbijenosti starog komunalnog otpada

    Jovana Janković, Dragoslav Rakić, Irena Basarić Ikodinović, Tina Đurić (2021)
    Bez obzira na savremene tretmane komunalnog otpada u svetu, u Srbiji je i dalje najčešći vid odlaganja na komunalne deponije, pa zbijanje otpada predstavlja jednu od ključnih faza formiranja deponije. Na ovaj način znatno se smanjuje zapremina otpada, ubrzava proces degradacije i produžava radni vek deponije. Zbog toga su geotehničke karakteristike komunalnog otpada prilikom zbijanja, veoma bitne kako u fazi projektovanja tako i u fazi izgradnje deponije i optimizacije prostora. Tu se pre svega misli na maksimalnu suvu zapreminsku ...
    komunalni otpad, deponija, Proktorov opit, optimalna vlažnost, maksimalna suva zapreminska težina

  • Tracking of the temporal dependency of fading of the human footprint temperature contrast

    Stevan Đenadić, Ljubiša Tomić, Vesna Damnjanović, Darko Vasiljević, Danica Pavlović (2021)
    In certain situations, it is extremely important to determine the exact time “someone” entered or crossed the forbidden zone of a military or strategic installation, a red zone of radioactive, chemical, or biological contamination, a bank or similar structure. Standard security measures include ordinary video surveillance using cameras that operate in the visible range of the electromagnetic spectrum, as well commercial thermal imaging cameras [1, 2]. The paper presents the results of experiments that suggest another possible use of ...

  • Application of stochastic models for mine planning and coal quality control

    Dejan Stevanović, Božo Kolonja, Ranka Stanković, Dinko Knežević, Mirjana Banković (2014)
    ... after 100 layers the standard deviation stabilizes. The curves with the fitted (thick), minimum, average and maximum (dashed) standard deviations vs. the number of layers were highlighted. Horizontal axis refers to the number of layers. Vertical axis refers to the standard deviation. An exponential ...
    ... included in this specific pile, and starts building the next pile. Average standard deviations for the organic sulfur from various pile sizes is given in fig. 8. The figure illustrates the results obtained for the intrapile standard deviation for each number of lay- ers tested. Note, the curves were plotted ...
    ... Sulfur content is treated as lognormally distributed random variable. The objec- tives of the model include minimizing the expected sulfur content and standard de- viation in sulfur content. The methodology was illustrated using the case study on Kolubara surface coal mine. Key words: stochastic modelling ...

  • Parametri zbijanja komunalnog otpada određeni različitim laboratorijskim metodama

    Jovana M Janković Pantić, Dragoslav R Rakić, Irena G Basarić Ikodinović, Tina D Đurić, Snežana Bogdanović (2021)
    Zbijanje komunalnog otpada predstavlja jednu od osnovnih faza korišćenja komunalne deponije. Zbog toga je kao i kod drugih nasutih građevina, veoma korisno odrediti parametre zbijanja: maksimalnu suvu zapreminsku težinu (dmax) i optimalnu vlažnost (wopt). Dobijeni rezultati mogu da posluže prilikom projektovanja kapaciteta deponije kao i prilikom definisanja obradivosti otpada. U dosadašnjoj praksi najčešći način određivanja parametra zbijanja je standardna metoda (Proktorov opit) koja se koristi u mehanici tla, uz eventualnu redukciju energije zbijanja. Međutim, različiti tretmani komunalnog otpada na ...
    deponija komunalnog otpada, zbijanje, Proktorov opit, malj sa šiljcima
    ... synthetic waste samples with different waste composition (Plandište landfill). The samples werc tested т standard Proctor apparatus at (ће same compaction energy, but with two different hammers: standard flat hammer and hammer with spikes. In this way, it is possible to compare thc results obtained by ...
    ... landfill as well as when defining the workability of waste. In current practice, ће most common method ог determination compaction parameters is by standard method (Proctor compaction test) used јп soil mechanics, with еуепша! reduction of compaction епегру. Although this methodology is accepted in some ...
    ... Laboratorijsko ispitivanje zbijanja komunalnog, otpada, slično је kao i kod ispitivanja zbijenosti tla, gde su uslovi propisani odgovarajućim standardima (SRPS EN 13286-2, ASTM D 1557). Ispitivanjima sc određuje optimalna vlažnost (Wopi) pri kojoj se postiže najveći učinak zbijanja, izražen suvom ...

  • Утицај похабаности резних елемената роторног багера на ниво вибрација погона за копање

    Филип Милетић (2023)
    У докторској дисертацији је анализиран утицај похабаности резних елемената роторног багера на потрошњу електричне енергије и ниво амплитуде вибрација погона за копање. Креиран је модел који у функцији стања резних елемената дефинише зависност разматраних физичких феномена. За развој модела примењене су једначине теорије осцилација и Ватметарска метода [1] којом се одређује потрошња електричне енергије. За верификацију модела извршена су мерења на роторном багеру SRs2000.32/5+VR ангажованом на откопавању откривке на површинском копу Тамнава–Западно поље. Обављено је пет мерења. Резни елементи су ...
    роторни багер, резни елементи, хабање, вибрације, потрошња електричне енергије

  • Efficiency and lifetime of medium voltage transformers

    Snežana Aleksandrović, Vesna Damnjanović (2017)

  • Upravljanje proizvodnjom nafte – novi alat na bazi fazi logike

    Мирослав Црногорац, Душан Даниловић, Лола Томић (2020)
    ... модуларној конструкцији. Вентил је врло робустан и добро опремљен за мобилне апликације. Примери примена укључују: кинематику котурача и торња или управљање ужадима торња, слика 7. Слика 8. Усмерни контролни вентил чине: 2.1 калем; 2.2 неповратни вентил; 2.3.1 вентил за контролу притиска А страна; ...
    ... krhotina stena, dodavanjem bušaćih alatki kako dleto napreduje u dubinu, vađenjem alatki iz bušotine. Postrojenje (slika 1) se u pravilu sastoji od: tornja 16; koturača 15 i 18; dizalice 11; pogonskih motora i prenosnika 12; obrtnog stola 11; isplačnih pumpi 13; isplačne glave 9; ...
    ... Uređaj se postavlja najmanje 30m od bušotine, kako bi se tokom erupcije, moglo nesmetano koristiti. Dodatni upravljački sklop postavlja se ispod tornja uz upravljačke sklopove postrojenja i povezan je s “koomey” uređajem. Na niskim temperaturama potrebno je akumulatore termički izolovati, zagreavati ...

  • Depth estimation of archeological objects using Euler 3D deconvolution of magnetic data

    Vesna Cvetkov, Ilija Vasiljević, Mirko Petković (2015)

  • LRMI markup of OER content within the BAEKTEL project

    Ranka Stanković, Daniela Carlucci, Olivera Kitanović, Nikola Vulović, Bojan Zlatić (2015)
    ... for the BAEKTEL metadata portal is based upon a metadata schema that contains elements taken from standard namespaces with guidelines for metadata creation. In metadata specification, the standard nomenclature was used, enabling learning resources to be described and shared in a common way, ...
    ... Learning Resource Metadata Initiative (LRMI), which makes it easier to publish, discover, and deliver quality educational resources on the web using standard schemas for HTML pages markup in ways recognized by major search providers: Google, Yahoo, Microsoft Bing. LRMI is proposed as an extension to the ...
    ... semantic annotation implementation with examples of resource tagging is given. Section 4 of this paper outlines the key aspects of the LRMI standard for describing educational resources, including metadata schema and implementation of LRMI metadata. In section 5 is given short description and ...

  • Testing the energy value of different types of coal by the method of active thermography

    Stevan Đenadić, Ljubiša Tomić, Vesna Damnjanović, Predrag Jovančić, Dragutin Jovković (2020)
    In this paper, coal thermograms are presented and analyzed in order to determine their energy value. Two types of coal of different categories, brown and lignite, were selected for active thermographic imaging. The tested coal samples were processed before measurement so that they are similar in dimensions and have two plane-parallel smooth surfaces. The test samples were "primarily" heated under the same conditions and the process of their cooling was monitored by a thermal camera. "Then" they were cooled ...
    Infrared imaging, nondestructive testing, active thermography, coal.

  • Geotehnički uslovi izgradnje nadvožnjaka "Balajnac" na autoputu E-80 deonica: Niš - Merošina

    Dragoslav Rakić, Nikola Božović (2024)
    U sklopu prve deonice autoputa E-80 Niš – Merošina, izgrađen je nadvožnjak u zoni sela Balajnac koji je oslonjen na tri stubna mesta na međusobnom rastojanju od oko 26 m. Svaki stub je fundiran na šipovima i to sa predloženim rasporedom od 2 šipa u grupi na međusobnom rastojanju od 3.6 m. U radu su na osnovu izvršenih geotehničkih istraživanja terena, analizirani rezultati nosivosti vertikalno opterećenog šipa prečnika 1.2 m i dužine šipa od L = 23 m. Analiza ...
    nadvožnjak Balajnac, šip, probno opterećenje šipa, projektni pristup, granična stanja

  • Primena digitalne fotogrametrije u rudniku Rudnik

    Nikola Mirković, Luka Crnogorac, Katarina Urošević (2023)
    Digitalna fotogrametrija, lasersko skeniranje i virtuelizacija sve više pronalaze aktivne uloge u rudarstvu, prvenstveno zbog svoje široke mogućnosti primene. Laserskim skeniranjem i fotogrametrijom snimaju se i kreiraju 3D modeli otkopa, jamskih hodnika, površinskih kopova, površinskih objekata (zgrada, spomenika, predmeta), a vrši se skeniranje celih rudnika koji se rekonstruišu u 3D digitalne modele. Fotogrametrija predstavlja proces fotografisanja objekata pomoću fotoaparata i daljom obradom fotografija u različitim softverskim alatima kreiraju se realne kopije 3D modela objekata ili predmeta u digitalnoj formi. Za ...
    digitalna fotogrametrija, prostorna vizuelizacija, rudarski objekti, podzemna eksploatacija

  • A Description of Morphological Features of Serbian: a Revision using Feature System Declaration

    Cvetana Krstev, Ranka Stanković, Vitas Duško (2010)
    In this paper we discuss some well-known morphological descriptions used in various projects and applications (most notably MULTEXT-East and Unitex) and illustrate the encountered problems on Serbian. We have spotted four groups of problems: the lack of a value for an existing category, the lack of a category, the interdependence of values and categories lacking some description, and the lack of a support for some types of categories. At the same time, various descriptions often describe exactly the same ...
    Morphology, Lexicon, lexical database, Standards for LRs
    ... using different approaches. We propose a new morphological description for Serbian following the feature structure representation defined by the ISO standard. In this description we try do incorporate all characteristics of Serbian that need to be specified for various applications. We have developed several ...
    ... Existing Descriptions We will illustrate inadequacies of existing morphological descriptions for Serbian on MULTEXT-East, serving as de facto standard for involved languages for many years. They can be grouped in several categories. (a) The lack of a value for an existing category. This problem ...
    ... reusable for present and future applications. Thus we have developed SprFSD following the feature structure representation defined by the ISO 24610 standard (ISO, 2007). As stated in (Lee & al., 2004) such representation enables specialists from diverse application fields to share detailed expertise ...

  • The effect of finite driving rate on avalanche distributions

    Sonja Radić, Sanja Janićević, Dragutin Jovković, Đorđe Spasojević (2021)
    Statistics, Probability and Uncertainty,Statistics and Probability,Statistical and Nonlinear Physics

  • Serbian NER&Beyond: The Archaic and the Modern Intertwinned

    Branislava Šandrih Todorović, Cvetana Krstev, Ranka Stanković, Milica Ikonić Nešić (2021)
    U ovom radu predstavljamo srpski književni korpus koji se razvija pod okriljem COST Akcije „Distant Reading for European Literary History” CA16204. Koristeći ovaj korpus romana napisanih pre više od jednog veka, razvili smo i učinili javno dostupnim Sistem za prepoznavanje imenovanih entiteta (NER) obučen da prepozna 7 različitih tipova imenovanih entiteta, sa konvolucionom neuronskom mrežom (CNN), koja ima F1 rezultat od ≈91% na test skupu podataka. Ovaj model je dalje ocenjen na posebnom skupu podataka za evaluaciju. Završavamo poređenje ...
    ... Collections with NE-annotations, http:// brat.jerteh.rs/index.xhtml#/eltec/ 1255 4.1 Gold Standard: SrpELTeC-gold The SrpNER system for Serbian introduced in Section 2 was used in the first stage of the gold standard preparation (dubbed SrpELTeC- gold) in order to automatically annotate Sr- pELTeC collection ...
    ... recognized as PERS, although a full name is given); or 3) model annotated something that is not present in the gold standard – false positives; 1258 [FN] an entity present in the gold standard was not recognized – false negatives. In the subsections that follow, we analyze the performances of our newly ...
    ... sented in Section 3. Based on the specifically tailored guidelines, different evaluators perfor- med careful checks and corrections, yielding a gold standard (SrpELTeC-gold). This ena- bled us to train a CNN-based NE recognizer, named SrpCNNER, presented in Section 4. Having the gold dataset, prepared as ...

  • Analiza primene višekriterijumskih metoda u optimizaciji izbora hidruličnih bagera na površinskim kopovima uglja

    Stevan Đenadić, Predrag Jovančić, Dragan Ignjatović, Filip Miletić, Ivan Janković (2019)
    Hidraulični bageri primenjuju se u različitim oblastima privrede a najzastupljeniji su u građevinarstvu i rudarstvu. Na površinskim kopovima sa kontinualnim sistemima, klasifikuju kao pomoćna mehanizacija a na površinskim kopovima sa diskontinualnim sistemima, kao osnovna mehanizacija. Kako je u oba slučaja njihova primena neizostavna, važno je izvršiti adekvatnu analizu postojećih podataka, u cilju optimizacije izbora tipa hidrauličnog bagera u odnosu na uslove rada datog površinskog kopa. U radu su opisane različite višekriterijumske metode koje su korišćene za analizu hidrauličnih bagera. ...
    višekriterijumske metode, površinski kop uglja, pomoćna mehanizacija, hidraulični bager
    ... tih mašina. Emisioni standard je parametar koji pokazuje koji je „ekološki standard“ zadovoljen od strane proizvo- đača opreme. Američki (US emission standards, Tier 1 – Tier 4) i Evropski (EU emission, Stage I – Stage IV) su najreferentniji i najprihvatljiviji standardi za ocenji- vanje ekološkog ...
    ... ekološkog uticaja motora sa unutrašnjim sagore- vanjem. Elementi koje Američki standard definiše su: COx, HC, NMHC + NOx, NOx, PM; Evropski standard definiše sadržaj: COx, HC, NOx, PM [5]. Lakoća održavanja i udobnost upravljanja su poka- zatelji koji utiču direktno na ljude koji su u stalnom, svakodnevnom ...
    ... Operativni troškovi Eksploatacioni parametri Prosek moto sati godišnje Tehnička raspoloživost Prosek intervencija Ekološki parametri Emisioni standard Ergonomski parametri Lakoća održavanja Udobnost upravljanja Snaga motora, sila kopanja, maksimalna dubina kopanja i pritisak u hidrosistemu ...

  • Building learning capacity by blending different sources of knowledge

    Ivan Obradović, Ranka Stanković, Olivera Kitanović, Dalibor Vorkapić (2016)
    ... of DC and the IEEE 1484.12.1-2002 Learning Object Metadata (LOM) standard elements (Barker, 2005) is proposed, as a basis for delivering web services for educational resources (Koutsomitropoulos et al., 2010). The LOM Standard groups data elements for describing a learning resource into nine ...
    ... 2008). As the amount of OER reaches a considerable size, it becomes important that each learning resource is well described and tagged in a standard way, and in machine readable form. This makes resources more easily located by search engines, and results returned by are more relevant. Both ...
    ... (Food and Agriculture Organization of the United Nations) Learning Object Resources Metadata Application Profile, which combines DC and LOM Standard, was taken as the basis1. Compliance with DC and LOM standards was chosen in order to enable sharing of BMP metadata with other OER repositories ...