Претрага

Упит dcterms_subject_txt:Global and Planetary Change

2342 items

  • Surface functional groups and degree of carbonization of selected chars from different processes and feedstock

    Marija Ilić, Franz-Hubert Haegel, Aleksandar Lolić, Zoran Nedić, Tomislav Tosti, Ivana Sredović Ignjatović, Andreas Linden, Nicolai D. Jablonowski, Heinrich Hartmann (2022)
    The knowledge ofthe structural and chemical properties of biochars is decisive for their application as technical products. For this reason, methods for the characterization of biochars that are generally applicable and allow quality control are highly desired. Several methods that have shown potential in other studies were used to investigate two activated carbons and seven biochars from different processes and feedstock. The chars were chosen to cover a wide range of chemical composition and structural properties as a hardness ...
    Biougalj, različiti procesi dobijanja, različite sirovine, površinski aktivne grupe, x-ray, FT-IR,XPS
    ... DJ, Amonette A, Street-Perrott FA, Lehmamn J, Joseph S. Sustainable biocharto mitigate global climate change. Nat Commun. 2010; 1: 1—9. http://dx.doi.org/10.1038/ncomms1053. Brown RC, The role of pyrolysis and gasification in a carbon negative economy. Processes. 2021; 9: 882—898. https://doi.org/10 ...
    ... the peaks above 3000 cm . The largest relative change between the treated and the untreated sample is found in the range between 1200 and 1500 cm"! and attributed to the dissolution of carbonate as will be demonstrated more clearly for the gasification biochars. Gasification biochars. The FT-IR ...
    ... filler in polymers [31,32] and building materials [33,34] or component in other composites [35]. The most discussed application of biochar is their use as a soil amendment leading to improved crop yield [36] and sequestration of a large amount of carbon as a sink in the global carbon cycle due to ...

  • Application of machine learning for diagnosing the operation of a deep well pump in oil production

    Maja Trikić (2024)
    This paper will thoroughly examine how machine learning can improve the diagnosis of deep well pumps by analyzing the role and function of the pumps, dynamograms, sensor technologies, and diagnostic methods.Our analysis will provide insights into modern techniques and approaches for enhancing the performance and reliability of oil production systems, targeting cost reduction and increased operational efficiency.
    deep well pump, dynamograms, machine learning, diagnostics of operating coditions,Random Forest, XGBoost
    ... vibration and temperature data. These descriptors can help detect anomalies that occur at specific frequencies. 2.Wavelet Descriptors: Wavelet Transform allows analysis of signals in both time and frequency domains. Wavelet descriptors are effective for analyzing signals that change over time ...
    ... sensors 2. Piezoresistive sensors- These sensors use variable resistors that change in response to pressure. The resistors are typically made from materials such as silicon crystals. Piezoresistive sensors are highly accurate and are often used in applications that require high precision. 31 k ...
    ... je n = 0,1,2.....N - 1 and a(k) are the Fourier coefficients of the contour. To make the descriptors invariant to rotation, the magnitude |a(R)|is used. However, in the case of dynamomerric charts, rotation invariance is not critical because some types of charts can change after rotation. This is ...

  • Study of the Synergetic Effect of Co-Pyrolysis of Lignite and High-Density Polyethylene Aiming to Improve Utilization of Low-Rank Coal

    Ivan Kojić, Achim Bechtel, Nikoleta Aleksić, Dragana Životić, Snežana Trifunović, Gordana Gajica, Ksenija Stojanović (2021)
    Polimeri i plastika, opšta hemija
    ... increase of short- chain n-alkanes and without a change in the content of mid-chain homologues is noticed (Table 7). Table 7. Values of Σn-alk-1-enes/Σn-alkanes ratio and values of common organic geochemical parameters based on distributions of n-alkanes in lignite EOM and the liquid products obtained in ...
    ... zation, I.K., K.S., and D.Ž.; methodology, I.K., A.B., G.G., N.A., S.T., D.Ž., and K.S.; formal analysis, I.K., A.B., N.A., S.T., and G.G.; investigation, I.K. and K.S.; writing—draft preparation, K.S. and I.K.; writing—review and editing, K.S. and A.B. All authors have read and agreed to the published ...
    ... ics of solid residues and gases obtained by lignite/HDPE co-pyrolysis were also studied and compared to those from pyrolysis of lignite and HDPE alone. Pyrolysis of lignite, HDPE, and their mixture (mass ratio, 1:1) was performed at various temperatures (400, 450, 500, 550, and 600 ◦C). For the char ...

  • The Importance of Detailed Groundwater Monitoring for Underground Structure in Karst (Case Study: HPP Pirot, Southeastern Serbia)

    Marina Čokorilo Ilić, Ana Mladenović, Marina Ćuk, Igor Jemcov (2019)
    Geography, Planning and Development,Aquatic Science,Biochemistry,Water Science and Technology
    ... constructed by standard excavation (first and last parts) and tubing (1/4 and 3/4) with concrete lining (Figure 1). Three observation wells, PP-1, PP-3 and PP-4, were deep-drilled along the tunnel and the screens installed within the tunnel zone. The HPP has a gravity dam and is usually operated 4–5 h/day. Surface ...
    ... the study area. 3. Materials and Methods Research activities and the selection of methods depended on the operating regime of the water-conveyance tunnel. The campaign lasted for 108 days and included the months of September, October and November 2016. Quantitative and qualitative groundwater data were ...
    ... problems, like changes in water quality and quantity, and in groundwater and surface water regimes [2]. These changes occur, not only in the construction phase, but also while the structures are in service. In most cases, the structures cannot be completely isolated and there is constant interaction with ...

  • An aproach to Implementation of blended learning in a university setting

    Ivan Obradović, Ranka Stanković, Olivera Kitanović, Jelena Prodanović (2011)
    ... groups: global reports and reports at the course level. Global reports can be used for a systematic insight in both system parameters of the Moodle platform and data related to user activity. The reports generated at the course level contain data on student activity within the course, and are ...
    ... instruction, and their obligations and responsibilities are undergoing a substantial change. The approach that combines elements of traditional and e-learning paradigms, which is thus hybrid in its nature, offers a great extent of flexibility in applying ICT to learning, and often goes under ...
    ... clients. LITERATURE [1] Devedzic, V., Education and The Semantic Web, International Journal of Artificial Intelligence in Education (IJAIED), Vol.14, No.2, pp.39-65, 2004. [2] Paulsen, M.F., Online Education and Learning Management Systems – Global E-learning in a Scandinavian Perspective, NKI ...

  • A Lexical Approach to Acronyms and their Definitions

    Cvetana Krstev, Duško Vitas, Ranka Stanković (2015)
    In this paper we present a comprehensive approach to acronyms for Natural-Language Processing (NLP) of Serbian texts. The proposed procedure includes extraction of acronyms and their definitions that are usual Multi-Word Units (MWUs), shallow parsing of MWUs that enables MWU lemmatization and production of entries in morphological electronic dictionaries, both for MWU and acronyms, that are provided with grammatical, syntactic, semantic and domain information. This approach enables representation that reflects complex relations between acronyms and their definitions.
    ... Electronic Communication and Postal Services’. Moreover, in many cases a relation between an entity and its name and acronym is not one-to-one. The name can change in time and some shortened variants can be in use, translated names can exhibit serious variations in used lexica and syntactic forms, original ...
    ... texts (57% daily, 8% weekly and 5% monthly newspapers) and 6% of monographs and textbooks (Krstev and Vitas, 2005), which are types of texts that tend to use acronyms and pro- vide definitions. Besides that we used two more samples of newspaper texts (having 600 thousand and 1.200 thousand simple word ...
    ... of Education and Science under grants 47003 and 178003. 6. References Jacobs, K., A. Itai, and S. Wintner, 2014. Acronym Dic- tionary Construction and Disambiguation (abstract). 3rd Parseme General Meeting – Poster Session. Krstev, C., R. Stanković, I. Obradović, D. Vitas, and M. Utvić, 2010 ...

  • OntoLex Publication Made Easy: A Dataset of Verbal Aspectual Pairs for Bosnian, Croatian and Serbian

    Ranka Stanković, Maxim Ionov, Medina Bajtarević, Lorena Ninčević (2024)
    Ovaj rad predstavlja novi jezički resurs za pretraživanje i istraživanje verbalnih aspektnih parova u BCS (bosanskom, hrvatskom i srpskom), kreiran korišćenjem principa Lingvističkih Povezanih Otvorenih Podataka (LLOD). Pošto ne postoji resurs koji bi pomogao učenicima bosanskog, hrvatskog i srpskog kao stranih jezika da prepoznaju aspekt glagola ili njegove parove, kreirali smo novi resurs koji će korisnicima pružiti informacije o aspektu, kao i link ka aspektnim parovima glagola. Ovaj resurs takođe sadrži spoljne linkove ka monolingvalnim rečnicima, Wordnetu i BabelNetu. ...
    aspekt glagola, lingvistički otvoreni podaci, BCS

  • Грешка инклинације код депозиционе реманетне магнетизације

    Mirko Petković, Vesna Cvetkov (2019)
    ... investigations of the re-deposition process, on mathematical models, showed that there was a change in the inclination of the depositional remanent magnetization, that is, that the inclination value before and after the experiment did not coincide. Laboratory testing on natural sediments confirmed ...
    ... particles, and correct for paleomagnetic inclination shallowing, Physics and Chemistry of the Earth 27, 1273 – 1279. 5. Jackson, M., Banerjee, S., Marvin, J., Lu, R., & Gruber, W., (1991) Detrital remanence, inclination errors, and anhysteretic remanence anisotropy: quantitative model and experimental ...
    ... the aim of defining the spatial and temporal position of the investigated rock complexes. The spatial position of the remanent magnetization vector is determined by the paleo declination and inclination. However, the processes of re-deposition, compaction and cementation of sediments lead to the ...

  • Design of a sucker rod pumping system

    Ana Ponoćko (2024)
    For a long time in the history of oil production, sucker rod pumps have been the first and in many cases the only choice when it comes to mechanical extraction methods. Proper selection of each individual element of the system enables optimization, which entails benefits in the form of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The ...
    sucker rod pump, fluid production, mechanical extraction methods,, Prosper, QROD, RODSTAR
    ... plunger cause large pressure changes. In cases where the fluid is more compressible (a mixture of gas and liquid), a change in volume is needed to decrease or increase the pressure, 1.e., to open and close the valves. This required volume can only be achieved through increased movement within the cylinder ...
    ... the bottom of the cylinder. The relationship between the distance traveled by the plunger and the pressure change caused by the fluid inside the pump depends on the 8 compressibility of the fluid mixture inside the cylinder. If the fluid is nearly incompressible, very small volume changes due ...
    ... of increased efficiency and reduced costs. The first part of the paper presents the underground and surface equipment of the rod pump and describes the operation of the entire system. The second part involves an analysis and calculations using the "RODSTAR", "QRod" and "Prosper" software, which ...

  • Evidence for Ladinian (Middle Triassic) platform progradation in the Gyulakeszi area, Tapolca Basin, Western Hungary: Microfacies Analysis and Biostratigraphy

    Zsolt Robert Nagy, Nevenka Đerić, Sándor Kovács, Anna Oravecz-Scheffer, Felicitász Velledits, Olga Piros, Gabor Csillag (2014)
    anizik, ladin, karbonati, litostratigrafija, biostratigrafija, konodonti, radiolarije, dijageneza
    ... carbonate platform and basin develop- ment. Soc. Econ. Paleont. Miney. Spec. Pub., 44: 3-13. Brack P., Rieber H., Nicora A. & Mundil R. (2005) – The Global boundary Stratotype Section and Point (GSSP) of the Ladinian Stage (Middle Triassic) at Ba- golino (Southern Alps, Northern Italy) and its impli- ...
    ... (Hungary) based on sedimentological and paleoecological studies|. Bwdl Hung. Geol. Soc, 127(1-2): 145-177 [in Hungarian with English abstract]. Voros A., Budai T., Haas J., Kovd4cs S., Kozur H. & Palfy J. (2003) – GSSP (Global Boundary Stratotype Section and Point). Proposal for the base of Ladinian ...
    ... during the Cwriona and rapid progradation during Gre- dleyi and Arcbelaus zones. Vartations in the rate of sub- sidence were interpreted as the driving force wbhile marked increase in carbonate production is suggested to be another important parameter behind the change from aggradation to ...

  • Tectonic evolution of the Circum-Moesian orocline of the Carpatho-Balkanides: Paleomagnetic constraints

    Emő Márton, Vesna Cvetkov, Miodrag Banješević, Gábor Imre, Aleksandar Pačevski (2024)
    Apuseni-Banat-Timok-Srednogorie belt, danubicum, paleomagnetism, oroclinal bending

  • A tool for identifying the criticality in the disordered systems with metastable dynamics

    Svetislav Mijatović, Dragutin Jovković, Sanja Janićević, Stefan Graovac, Đorđe Spasojević (2021)
    Физика кондензоване материје

  • Petrofizička svojstva krečnjaka postamenta spomenika „Pobednik” na Beogradskoj tvrđavi

    Dijana Trajković (2024)
    Spomenik „Pobednik” je podignut 1928. godine na Gornjem gradu Beogradske tvrđave. Spomenik je predstavljen bronzanom muškom figurom sa orlom u desnoj ruci i spuštenim mačem u levoj ruci i delo je vajara Ivana Meštrovića, dok je postament delo arhitekte Petra Bajalovića. Postament je u vidu dorskog stuba sa kanelurama na visokoj kubičnoj bazi i izgrađen je od krečnjaka o čijem poreklu ne postoje zvanični literaturni podaci, ali u korelaciji sa ostalim objektima Beogradske tvrđave, pretpostavlja se da je za ...
    spomenik „Pobednik”, krečnjak, petrofizička svojstva, kompatibilnost
    ... Milivojević, J., Đerić, N., 2013. The evolution ofa key segment in the Europe-Adria collision: the Fruska Gora of northern Serbia. Global and Planetary Change 103, str. 39-62. Vanušić, D., 2008. Podizanje spomenika pobede na Terazijama, Nasleđe IX, Beograd, str. 193-210. Vučetić — Mladenović ...
    ... figure with an eagle in his right hand and a lowered sword in his left and is it work of sculptor Ivan Meštrović while the pedestal is the work of architect Petar Bajalović. The pedestal was designed in the formo f a Doric column with chapels on a high cubic base and was built of limestone, the origin ...
    ... слободном приступу. - Претрага репозиторијума доступна је на www.dr.rgf.bg.ac.rs The Digital repository of The University of Belgrade Faculty of Mining and Geology archives faculty publications available in open access, as well as the employees' publications. - The Repository is available at: www.dr.rgf ...

  • Indexing of textual databases based on lexical resources: A case study for Serbian

    Ranka Stanković, Cvetana Krstev, Ivan Obradović, Olivera Kitanović (2015)
    In this paper we describe an approach to improvement of information retrieval results for large textual databases by pre-indexing documents using bag-of-words and Named Entity Recognition. The approach was applied on a database of geological projects financed by the Republic of Serbia in the last half century. Each document within this database is described by metadata, consisting of several fields such as title, domain, keywords, abstract, geographical location and the like. A bag of words was produced from these ...
    ... Krstev, C.: Developing and Maintaining a WordNet: Procedures and Tools. In: Orav, H., Felbaum, C., Vossen, P. (eds.) Proceedings of the Seventh Global Wordnet Conference, GWC 2014. pp. 55–62. Tartu, Estonia (2014) 13. Nadeau, D., Sekine, S.: A Survey of Named Entity Recognition and Classification. In: ...
    ... precision in the intersection Fig. 2. Precision-recall curve for the first query (zlato OR Au) AND (Bor OR Borski okrug): left, retrieval wihout index; right, retrieval with index. point k, and ∆(k) is the change in recall from items k − 1 to k. The results show that for 4 queries AP was higher in the old ...
    ... of geologic data, and provide a modern and effective in- formation basis for carrying out all activities related to planning, design and decision-making in the field of geology. Within the project a web portal3 was established that allows quick and easy access to geological data and information in the ...

  • Frequency and Length of Syllables in Serbian

    Marija Radojičić, Biljana Lazić, Sebastijan Kaplar, Ranka Stanković, Ivan Obradović, Ján Mačutek, Lívia Leššová (2019)
    Basic analyses of several properties of syllables (the rank-frequency distribution, the distribution of length, and the relation between length and frequency) in Serbian is presented. The syllabification algorithm used combines the maximum onset principle and the sonority hierarchy. Results indicate that syllables behave similarly to words as far as mathematical models are concerned, but values of parameters in models for syllables are quite different from those for words.
    frekvencije slogova, dužina slogova, srpski jezik
    ... g. Lower and Upper Sorbian among Slavic languages). In addition, the rules derived from Pulgram’s approach can change relatively quickly, as lexicon is one of the more dynamic language features. Therefore, we follow another approach, namely, a combination of the maximum onset principle and the sonority ...
    ... (2008). Frequency and Length of Syllables in Serbian 117 3. Language material Serbian is a South Slavic language. It has the official status in Serbia (exclusively) and in Bosnia and Herzegovina (as one of three languages, together with Bosnian and Croatian), and the status of a minority ...
    ... distinguishing between marginal (rarely occurring and considered to be exceptions) and non-marginal (found with a high frequency) consonant clusters at beginnings and ends of words; only those which are not marginal are allowed to form syllable onsets and codas. If one follows his modification, a large ...

  • Adsorption and degradation of some psychiatric drugs by sol-gel synthesized titania-based photocatalysts: influence of tungsten and sodium content

    Nina L. Finčur, Maja J. Šćepanović, Mirjana Grujić-Brojčin, Biljana F. Abramović, Jugoslav B. Krstić, Aleksandar Kremenović, Tatjana Srećković, Aleksandar Golubović (2019)
    Mesoporous anatase nanopowders were doped with 0.05−0.5 mol% of W6, in order to obtain more efficient photocatalyst than TiO2 Degussa P25 in the degradation of amitriptyline (AMI) under simulated solar irradiation (SSI). Dominant XRPD peaks were ascribed to anatase phase, with additional peaks which could correspond to brookite, TiO2 bronze and sodium titanate, Na2Ti9O19. The Raman scattering measurements have confirmed anatase as dominant phase, with broad Raman feature at ~270 cm−1 possibly related to Ti–O–Na stretching vibration. All W-doped ...
    Sol-gel synthesis, Doped titania nanopowders, XRPD, Raman spectroscopy, Adsorption and photocatalytic degradation, Psychiatric drugs

  • 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
    ... 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 different compaction procedures, and cffect of ће wastc composition on compaction conditions is determined. Кеу words: municipal ...
    ... of сотраспоп characteristics of fresh and degraded municipal solid waste, Wastc Disposal & Sustainable Energy, 2020. Hanson J.L., Yesiller М., Von Stockhausen S.A., Wong W. W.: Сотраспоп Characteristics of Municipal Solid Waste, Journal ог Geotechnical and Geocnvironmcental Engincering, Vol. 136 ...
    ... ltoh T., Тоећаја 1., Kawano Y., Kameda M., Fukvi S., Koelsch F., and Yonai, У : Mechanical Properties of Minicipal Waste Deposits апа Ground Improvement, Proceedings of the Sixteenth International Coference on Soil Mechanich and Geotechnical Enginering, Volume 4, Millpress Science Publishers, Rotterdam ...

  • Definition of groundwater genesis and circulation conditions of the complex hydrogeological karst system Mlava–Belosavac–Belosavac-2 (eastern Serbia)

    Ljiljana Vasić, Saša Milanović, Zoran Stevanović, Laszlo Palcsu (2020)
    Geochemistry and Petrology

  • Terminology Acquisition and Description Using Lexical Resources and Local Grammars

    Cvetana Krstev, Ranka Stanković, Ivan Obradović, Biljana Lazić (2015)
    Acquisition of new terminology from specific domains and its adequate description within terminological dictionaries is a complex task, especially for languages that are morphologically complex such as Serbian. In this paper we present an approach to solving this task semi-automatically on basis of lexical resources and local grammars developed for Serbian. Special attention is given to automatic inflectional class prediction for simple adjectives and nouns and the use of syntactic graphs for extraction of Multi-Word Unit (MWU) candidates for ...
    ... Table 1: Excerption from dataset with ending. (m: masculine gender; f: feminine gender; m/f: nouns change gender in their inflectional paradigm) Analysis of the relation between word end- ings and inflectional FST classes shows that the prediction of inflectional class by the abovemen- tioned s ...
    ... optics, medicine, physics and mathematics, psy- chology) showed that 97% of multi-words in these sources consist of nouns and adjectives only, and more than 99% consist only of nouns, adjectives, and a preposition. (Justeson & Katz, 1995) Identifying the adjectives and the preposi- tional phrase ...
    ... Acquisition and Description Using Lexical Resources and Local Grammars Cvetana Krstev, Ranka Stanković, Ivan Obradović, Biljana Lazić Дигитални репозиторијум Рударско-геолошког факултета Универзитета у Београду [ДР РГФ] Terminology Acquisition and Description Using Lexical Resources and Local Grammars ...

  • Development and Evaluation of Three Named Entity Recognition Systems for Serbian - The Case of Personal Names

    Branislava Šandrih, Cvetana Krstev, Ranka Stanković (2019)
    In this paper we present a rule- and lexicon-based system for the recognition of Named Entities (NE) in Serbian news paper texts that was used to prepare a gold standard annotated with personal names. It was further used to prepare training sets for four different levels of annota tion, which were further used to train two Named Entity Recognition (NER) sys tems: Stanford and spaCy. All obtained models, together with a rule- and lexicon based system were evaluated on ...
    NER, Named Entity Recognition Systems, Serbian, Personal Names
    ... steps can be omitted and can change order; however, it performs best when used in predefined way since in each step the disambiguation of some names is performed. SRPNER presented in (Krstev et al., 2014) rec- ognizes 11 classes of NEs: dates (moments and periods), time (moments and periods), money ex- ...
    ... are three categories of NER systems: 1) The rule-based (RB) (Krupka and Hausman, 1998; Friburger and Maurel, 2004); 2) the Ma- chine Learning (ML) based (Finkel and Manning, 2009; Singh et al., 2010); and 3) hybrid meth- ods (Jansche and Abney, 2002). The ML-based methods can often be “black boxes”, in ...
    ... appli- cation that enables NER across many languages and domains),1 OpenNLP (rule-based and statisti- cal NER),2 spaCy (Honnibal and Montani, 2017) (module written in Python, used for advanced NLP)3 and many others. For Serbian, thus far a rule-based and lexicon-based NER system was developed – SRPNER (Krstev ...