Serbian Academy of Sciences and Arts
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The Romanian Orthodox Church in Serbia today: between history and modernity
No full textУ овом раду истражује се савремено стање Румунске православне цркве
у Србији, са посебним освртом на њену улогу у очувању верског и културног идентитета румунске заједнице. Анализирани су историјски контекст, демографски и социо-културолошки контекст, као и утицај цркве на свакодневни живот верника. Истраживање је засновано на полу-структурисаним интервјуима са румунским православним свештеницима, као и на анализи црквене штампе и званичних извора. Рад наглашава изазове попут демографског опадања, језичких баријера и опадања интересовања за цркву и истиче значај цркве у очувању културног и духовног наслеђа
румунске заједнице у савременом српском друштву
On Collective Nouns Ending in -ad in Old Štokavian and Prizren-Timok Dialects
No full textПредмет истраживања су збирне именице на -ад (бурад, телад) у служби множине именица средњег рода с проширењем основе -т- (-ет-) у небалканизираним староштокавским и балканизираним (српским) говорима. На основу одабране дијалектолошке литературе испитује се најпре колико су ове именице познате на поменутом дијалекатском простору, а затим се разматра инвентар њихових наставака у говорима где врше службу множине именица средњег рода. Показало се да су ове збирне именице добро сачуване једино у зетско-сјеничком дијалекту, где су увелико захваћене процесом плурализације (као уосталом и у херцеговачко-крајишком и шумадијско-војвођанском дијалекту), и то у свим падежима, осим номинатива (и акузатива), да се, такође, чувају у ретким смедеревско-вршачким и неким нетипичним косовско-ресавским говорима, док су призренско-тимочкој дијалекатској области оне непознате. Изостанак именица на -ад, дакле, карактеристичан је за широку дијалекатску зону која захвата исток, југ и средишње делове СрбијеThe study deals with collective nouns ending in -ad (e.g. burad, telad), which serve as plural forms of neuter nouns with a stem extension -t- (-et-) in both non-Balkanized Old Štokavian and Balkanised (Serbian) dialects. Based on selected dialectological literature, the study first examines the presence of these nouns in the aforementioned dialectal area and then analyses the inventory of their endings in the dialects where they are used as plural forms of neuter nouns. It has been demonstrated that Old Štokavian dialects lack uniformity in preserving collective nouns ending in -ad, unlike Neoštokavian dialects. That these nouns are widespread only in Ijekavian dialects with older accentuation patterns (Zeta-Sjenica), followed by the rare Smederevo-Vršac and some atypical Kosovo-Resava speeches. They are entirely unknown in the Prizren-Timok dialectal area. The absence of nouns ending in -ad is observed in a broad dialectal zone encompassing the eastern, southern, and central parts of Serbia. Moreover, in the areas where collective nouns ending in -ad are still in use, they have been significantly affected by the process of pluralization, as is the case in the Herzegovinian-Krajina and Šumadija-Vojvodina dialects. However, neither in these areas has this process progressed evenly
Usage of the Whisper Large v3 Sr model for the transcription of Serbian spoken language in Python programming language on the Google Colab platform
No full textУ овом раду представљен je скрипт у програмском језику Пајтон (енг. Python) на платформи Гугл колаб (енг. Google Colab) који користи фино подешени модел за транскрипцију говора на српском језику Whisper Large v3 Sr (https://huggingface.co/Sagicc/whisper-large-v3-sr-cmb), чиме се омогућава бесплатно, квалитетно и једноставно транскрибовање говора на српском језику у текст. Мотивација за креирање овог скрипта проистекла је из недостатка доступних алата који истраживачима пружају једноставно коришћење овог модела без потребе за напредним техничким знањима и значајним рачунарским ресурсима. Овај скрипт омогућује једноставно учитавање аудио-записа, њихову транскрипцију помоћу модела Whisper Large v3 Sr и преузимање транскрипције у текстуалном формату. У раду ће најпре укратко бити описан горенаведени модел који скрипт користи, а затим ће детаљно бити описан начин функционисања самог скрипта, уз упутство за коришћење. Такође, биће представљени проблеми које је било неопходно превазићи за успешну примену овог приступа, као што је потреба за аутоматском сегментацијом звучних записа, одређивање оптималних параметара сегментације и омогућавање подршке за различите формате аудио-материјала. Осим тога, биће представљено неколико приступа везаних за смањивање броја грешака у транскрипцији. На крају, биће приказана евалуација тачности и ефикасности транскрипције, као и статистичка анализа уочених грешака. Сматрамо да овај алат може бити од великог значаја за истраживаче, с обзиром на то да убрзава процес обраде говорних података, омогућава обраду велике количине аудио-материјала у кратком периоду и пружа конзистентан и поновљив метод транскрипције, што је нарочито значајно за научну методологију и поновљивост истраживања везаних за језик. Поред тога, сматрамо да алат може бити користан и другим корисницима, с обзиром на то да омогућава једноставно креирање титлова за видео-садржаје, претварање аудио-бележака у текстуални формат, стварање аутоматски генерисаних транскрипата за особе са оштећеним слухом, као и стварање текстуалних архива аудио-садржаја.This paper presents a Python script on the Google Colab platform, which uses a fine-tuned model for the transcription of speech in Serbian, Whisper Large v3 Sr (https://huggingface.co/Sagicc/whisper-large-v3-sr-cmb), which enables free, high-quality and simple transcription of Serbian speech into text. The motivation for creating this script came from the lack of available tools which would allow researchers to use this model in a straightforward way, without the need for advanced technical knowledge and significant computing resources. This script provides a simple method for uploading audio files, transcribing them using the Whisper Large V3 Sr model, and downloading the transcription of the files in a textual format. Firstly, the paper briefly describes the aforementioned model used by the script, followed by a detailed description of how the script functions, along with a user manual. The paper will also present problems which we needed to overcome in order to successfully implement this approach, such as the need for automatic audio file segmentation, the determination of the optimal segmentation parameters, and the implementation of support for different audio file formats. Furthermore, several approaches related to the reduction in the number of errors in the transcription will be presented. We believe that this tool can be of significant importance to researchers, considering that it speeds up the processing of audio data, enables users to proces vast amounts of audio material in a short period of time, and provides a consistent and repeatable transcription method, which is very significant for the scientific methodology and the repeatability of language-related research. We also believe that the tool can be useful to other users, considering the fact that it enables creating subtitles for video content, converting audio notes into text, creating automatically generated captions for the deaf and hard of hearing, as well creating textual archives of audio content
Cities in energy transition: Local responses to national challenges
No full textGiven that cities are major consumers of energy and significant sources of carbon dioxide emissions, this research aims to explore pathways for their decarbonization. At the same time, recognizing that cities are not isolated energy islands but integral parts of national energy systems, the study investigates how the Energy Sector Development Strategy of the Republic of Serbia up to 2040 with Projections up to 2050 can be effectively scaled and adapted to the local context, using the city of Kragujevac as a case study. Three development scenarios were analyzed: Scenario 1: implementation of National Development Strategy measures that are feasible at the local level: Scenario 2: enhancement of the Strategy by incorporating local potentials not currently addressed in the national framework, and Scenario 3: further development of the district heating system to enable greater integration of renewable energy sources. The research employs a multi-criteria decision analysis (MCDA) approach, involving diverse stakeholders, including citizens, academia, NGOs, and local policymakers. Through surveys, priority criteria for evaluating the proposed measures were identified, enabling a comparative analysis of the scenarios. The results provide valuable insights into local preferences and capacities for energy transition and offer recommendations for improving strategic alignment between national and local energy planning
Non-linear Transport in Microwave Generated Plasma
No full textExcitation of a plasma with microwaves has the advantage that the lifetime of ions and electrons is much longer than the oscillation period. At a frequency of 2.45 GHz the electron density is constant in time, therefore one expects a constant conductivity. A special behavior occurs at low pressures (<50 Pa), where the mean free path is comparable with the amplitude of the free electron motion accelerated in the electric field (\sim 1 \mu \mathrmm). Moreover, for the electric field strength in our microwave driven ICP source (described in [1]) of \sim 10 \textkV/\mathrmm for 50 W input power, it results a ballistic speed due to acceleration of the free electrons of 105-106 m/s, comparable with the thermal speed, assuming an electron temperature of about 1 \texteV(\sim 10000 \mathrmK). In this case the scattering frequency depends on the instantaneous value of the electric field, as suggested in [2]. As consequence the plasma conductivity is modulated in time and harmonics appear. We detected experimentally such harmonics for ICP and CCP sources in identical gas conditions. Some theoretical and experimental contributions on ICP discharges attribute the nonlinearity to Lorentz force effects [3]–[4]. However, the magnetic field (0.5 mT in our condition) would influence at most the transport in the ICP source. Our experiment shows the strongest effect in the CCP source. An alternative interpretation is that the nonlinearity comes from the Debye sheets close to the electrodes (CCP) or to the quartz tube (ICP source). However, the space charge length and the diode-like behavior (eventually responsible for nonlinearity) depends mainly on the electron density, not on the mean free path i.e. not on pressure. Moreover, in the inductive case, the Debye sheet is not involved in transport
Processing, structure and fracture behaviour of VNbTaXWC5 (X=Cr, Mo) high-entropy carbides
No full textThe improvement of room temperature fracture toughness of brittle transition metal carbides is demanding for the development of next-generation ultra-high temperature ceramics. Experiments have revealed that the increase of effective valence electron concentration (VEC>9) in high-entropy carbides (HECs) promotes the brittle to ductile transition. Recent calculations have predicted the synthesizability of VNbTaXWC5 (X=Cr, Mo) compositions, belonging to the highest deformability HECs with a VEC of 9.4, which are addressed to be investigated in the present work. The compositions were synthesised from both oxide and carbide precursors using carbothermal reduction and spark plasma sintering. Structural characterisation (XRD, SEM and EDS) revealed the formation of single-phase rock salt structures with homogenous distribution of metal elements. The samples were subjected to micro/nanoindentation to determine hardness and elastic modulus. The fracture behaviour of the compositions was studied using three-point bending of Single-Edge V-Notched Beams (SEVNB). The fracture toughness values were found to be similar for both compositions, with values in the range of KIC=2.9-3.4 MPam0.5, depending on the precursor quality and processing routes. These values are in the range of data reported for other HEC compositions measured by indentation methods, which generally overestimate the real fracture toughness
High-entropy ultra-high temperature ceramics
No full textHigh-entropy ultra-high temperature ceramics (HE-UHTC) are an innovative group of materials that have higher hardness than most other materials. Due to high hardness and ultra-high melting temperature, these materials can be used in extreme environments. Transition metals borides, carbides, carbonitrides and their composites are typically used for these purposes. Composites based on dual phase high-entropy carbides/high-entropy borides (HEC/HEB) showed higher hardness than the individual constituents. However, these composites have some challenges related to processing paths. This presentation will focus on synthesis, phase evolution, and microstructure development of HE-UHTC. The effect of transition metal constituents on their mechanical properties will be discussed. For this study, dual phase HEC/HEB composites were synthesized by boro/carbothermal reduction and densified by spark plasma sintering.Varying transition metals influenced their morphology, grain sizes and Vickers hardness. The production of the dual HEC/HEB showed a synergistic hardening effect when the ceramic was optimized, whereby some compositions had higher hardness values than individual high-entropy carbide and high-entropy boride phases containing the same transition metals
From RTA to conventional annealing: Impact on optical losses and metallic character of TiN films
No full textThis study investigates the effects of rapid thermal annealing (RTA) and conventional annealing on the optical and metallic properties of TiN thin films. TiN films were subjected to Au ion implantation, followed by RTA and conventional annealing at 400°C and 500°C for 1 h. Ion implantation led to a decrease in metallicity and optical losses compared to the as-deposited film, with plasma frequency increasing from 6.44 eV to 8.85 eV and Drude broadening from 0.82 eV to 2.43 eV. After RTA, both plasma frequency and Drude broadening were lowered to 4.95 eV and 0.73 eV, respectively, enhancing the metallic character and further minimizing optical losses. Conventional annealing at 400 °C and 500 °C also decreased metallicity but resulted in comparable losses to RTA. However, losses slightly increased at 500 °C due to the growth of Au nanoparticles, which introduced additional scattering mechanisms. These findings demonstrate the importance of thermal treatments in tuning TiN films’ optical and electronic properties, with RTA offering similar results to conventional annealing but with shorter processing times, making it ideal for applications requiring low optical losses and metallic characteristics. © 2025 Elsevier B.V.This is the peer reviewed version of the paper: Novaković, Mirjana, Jugović, Dragana, Popović, Maja, "From RTA to conventional annealing: Impact on optical losses and metallic character of TiN films" in Optical Materials, 160 (2025):116718, [https://doi.org/10.1016/j.optmat.2025.116718
The catalytic effect of cobalt and influence of mechanical milling on hydrogen storage system MgH2 – Co using small milling time
No full textThe addition of cobalt to MgH₂ powder and forming MgH₂ - Co composites was investigated for small milling times. The composite powders were synthesized for 15, 30, and 45 min and characterized by XRD, SEM-EDS, PSD, DSC, and TPD methods. During TPD analysis, a kinetic model for the hydrogen desorption process was also determined. The hydrogen desorption reaction in catalyzed samples is described by the Avrami-Erofeev model with the value of parameter n=4. The Ea (apparent activation energy) for the hydrogen desorption reaction was decreased with the increase in milling time and the addition of transition metal. The uniform distribution of transition metal decreases hydrogen desorption temperature by more than 100 °C compared to the pure MgH₂ and purely milled MgH₂. The quantity ratio of released hydrogen reached the highest value (LT/HT=3.38) for a sample with the highest amount (20 wt.%) of additive and the longest milling time (45 min). LT maxima appear at 310 °C, significantly reducing desorption temperature compared to commercial MgH₂ (480 °C). The short milling times improve desorption properties by lowering the hydrogen desorption temperature enhancing the effect of catalyst. In this approach, mechanosynthesis can be analyzed as two independent processes—grinding and catalytic effects. For the studied milling times, the catalytic influence of Co is dominant in the hydrogen desorption process
