University of Niš: Facta Universitatis (E-Journals) / Универзитет у Нишу
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PRILOG DEMISTIFIKACIJI POJMA I PROCESA TRANZICIJE I ULOGE INTERNET GENERACIJE KAO DRUŠTVENOG AKTERA
No full textWe live in the age of parentheses and megatrends (J. Nisbet). Despite the visible signs and “arrows of time” pointing towards the new horizons of the future that has begun, there are still many old and new mystifications about the nature of the changes we are going through globally, regionally and locally. The paper deals with the concept of transition and the role of the Internet generation in the context of the interpretation of various theoretical viewpoints, discourses and perspectives (starting from the neoliberal, through meritocratic-elitist and all the way to the social-democratic ones), with special reference to practice and tendencies in the contemporary Serbian society. In the concluding remarks it is pointed out that despite the tendency to impose only one model of transition and the unipolar development, one should also take into account the existence of different types/models of transition, the multiplicity of social actors, as well as the contradictory nature, status and role of the Internet generation.Živimo u doba parenteze i megatrendova (Dž. Nizbet). Uprkos vidljivim smerokazima i „strelama vremena“ ka novim horizontima budućnosti koja je počela, još uvek je mnogo starih i novih mistifikacija o prirodi promena kroz koje prolazimo kako na globalnom planu tako i regionalnom i lokalnom nivou. U radu se problematizuje pojam tranzicije i uloga internet generacije u kontekstu interpretacije različitih teorijskih stanovišta, diskursa i perspektiva (od neoliberalnog, preko meritokratsko-elitističkog do socijal-demokratskog), sa posebnim osvrtom na praksu i tendencije u savremenom društvu Srbije. U zaključnim razmatranjima ukazuje se: da uprkos tendenciji da se nametne samo jedan model tranzicije i unipolarnog razvoja, na postojanje različitih tipova/modela tranzicije, na mnogolikost društvenih aktera kao i protivrečnu prirodu, status i ulogu internet generacije
EFFECT OF ISOTHERMAL AND ISOCHRONAL AGING ON THE MICROSTRUCTURE AND PRECIPITATE EVOLUTION IN BETA-QUENCHED N36 ZIRCONIUM ALLOY
Full text linkIn this study, the effect of isothermal and isochronal aging is reported to investigate the precipitate evolution and recrystallization of N36 zirconium alloy after β-quenching. Two groups of samples were cut from the as-received sheet of N36 zirconium alloy and subjected to solution treatment and subsequent aging at 580, 640, and 700 °C for 40 and 600 min, respectively. Optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and electron backscattering diffraction (EBSD) were utilized to characterize the microstructure and second-phase particle (SPPs) evolution. Results show that the implemented quenching after solution treatment produces fine interlaced α-plates structure conserved inside prior β grain boundaries with 12 variant directions that follow Burger misorientation characteristics. After aging for a short time, initial α-plates conserve their shape and become softer, and SPPs spread along their boundaries. Recrystallizations are finished for specimens aged at a higher temperature or for a longer time. The recrystallized structure exhibits non-uniform grains and a random SPPs distribution. Despite the differences in morphology, some recrystallization grains retain the orientation feature from the initial α-plates. Hardness declines as temperature and time rise, and no hardness peak is seen. Roughness and wettability rise with increasing ageing temperatures
BEGINNINGS OF THE ESTABLISHMENT OF THE "EDUCATIONAL GROUP" EO (EKPAIDEFTIKÓS OMILOS) AND ITS BASIC OPERATING FRAMEWORK IN GREECE
Full text linkThe announcement refers to the establishment process and the basic components of the operation of the newly established EO (program, purpose, preliminary declaration of establishment). The EO was an Athenian union with philological and literary deviations and a liberal urban character, ideologically positioned in the middle of the road, a union of intellectuals (Bella, 2018). Its activity lasted from 1910 to 1930 and focused on drafting programs for Greek schools, editing and publishing books, pamphlets, and organizing educational work through speech and lectures within and beyond the Club.Initially, it includes the positions and concerns of its founders and later pioneers (Triantafyllidis, Petrokokkinos) regarding its "hasty" establishment. It then references official documents such as the Foundation Draft, the Declaration of Foundation of the EO and a Letter to potential members. Finally, basic information is provided at the beginning and continuation of its operations, as well as its main actions until the split of its members in 1927. In this context, the Administrative Committee of the Group was set up, space was rented for meetings and speeches were given
DRONE SELECTION FOR FOREST SURVEILLANCE AND FIRE DETECTION USING INTERVAL VALUED NEUTROSOPHIC EDAS METHOD
Full text linkForest fires are one of the major causes for deforestation resulting in significant economic and environmental losses. The application of drones has been extended to various areas including disaster management. Since drones offer numerous advantages like real-time surveillance, task planning capabilities and autonomy, they are utilized in early detection systems for forest fires. The selection of a drone type for this purpose involves a complex system of multiple factors and conflicting information, for which the use of multi-criteria decision-making (MCDM) methods have been found to be yielding effective results. The aim of this study is to present a decision framework for drone selection problem in the context of forest fire surveillance and detection. This study contributes by (i) pointing out to the gap that the drone selection problem for forest surveillance and fire detection has been sparsely addressed, (ii) presenting an extensive literature review, (iii) extracting the relevant criteria through a literature review and interviews with the experts in field, (iv) assessing the alternatives by the proposed framework based on interval valued neutrosophic evaluation based on distance from average solution (IVN EDAS) method. The proposed framework is demonstrated by a case study consisting of four drone alternatives and 14 criteria. In accordance with the extant literature, the criteria related to the visual capabilities and diagnosis are evaluated as the most crucial features. A sensitivity analysis is carried out to check for the robustness by varying the criteria weights and a comparative analysis is conducted with interval valued neutrosophic technique for preference by similarity to the ideal solution (IVN TOPSIS) and interval valued neutrosophic combinative distance-based assessment (IVN CODAS) methods to validate the veracity of the method
ZAKONODAVNI OKVIR ZA DRUŠTVENE UTICAJE U PROSTORNOM PLANIRANJU RUDARSKIH REGIONA
No full textSpatial planning of development in mining regions is directed by the legislative framework, since mining activities, in addition to positive ones (economic progress), have numerous negative impacts at the local and regional level. Beside environmental degradation, social & community consequences of the planned development in mining regions (involuntary resettlement, company and boom towns, endangered indigenous rights, impoverishment) are very complex and demanding to direct and mitigate.The paper is devoted to analysis of the international legislation regulating social impacts of mining activities, including both hard and soft laws. This is followed with the critical analysis of appropriate national legislation of the Republic of Serbia, including the most relevant strategies and laws. The main aim is to identify existing problems and inconsistencies, as well as to provide proposals for improvements to facilitate more sustainable and socially sound development of mining regions. The resulting indications regarding Serbia reveal: (1) partial and delayed inclusion of international norms and standards, including transposition of the EU legislation; (2) social impacts are briefly mentioned, without elaboration of mitigation measures (declarative approach), (3) several relevant strategies are outdated, or even abolished without proper replacement; and (4) the emphasis is on environmental aspects, while consideration of other social impacts is poor and sporadic. Adoption of a single act to regulate mining-related development would overcome hierarchical and horizontal inconsistency, omissions, and include neglected aspects i.e. social impacts of resource extraction.Prostorno planiranje razvoja u rudarskim regionima je uslovljeno zakonodavnim okvirom, pošto rudarske aktivnosti, osim pozitivnih (ekonomski napredak), imaju brojne negativne uticaje na lokalnom i regionalnom nivou. Pored degradacije životne sredine, posledice planskog razvoja u rudarskim regionima (prinudno raseljavanje, kompanijski gradovi, ugrožavanje prava starosedelaca, osiromašenje) su vrlo kompleksne, a njihovo usmeravanje i ublažavanje je zahtevno.Rad je posvećen analizi međunarodnog zakonodavstva koje reguliše društvene uticaje rudarstva, uključujući „tvrde“ i „meke“ zakone. Nakon toga sledi kritička analiza odgovarajućeg nacionalnog zakonodavstva Republike Srbije, uključujući najrelevantnije strategije i zakone. Glavni je cilj identifikovati postojeće probleme i nedoslednosti, kao i dati priedloge za poboljšanja kako bi se omogućio održiviji i socijalno prihvatljiviji razvoj rudarskih regiona. Dobijeni rezultati za Srbiju otkrivaju: (1) delomično i odgođeno uključivanje međunarodnih normi i standarda, uključujući transpoziciju zakonodavstva EU; (2) društveni utjecaji se kratko spominju, bez razrade mera za ublažavanje (deklarativni pristup), (3) nekoliko relevantnih strategija je zastarelo ili čak ukinuto bez odgovarajuće zamene; i (4) naglasak je na ekološkim aspektima, dok je razmatranje ostalih društvenih uticaja slabo i sporadično. Donošenjem jedinstvenog akta kojim bi se regulisao razvoj rudarstva prevazišle bi se hijerarhijske i horizontalne nedoslednosti i propusti, te uključili zanemareni aspekti, odnosno društveni uticaji ekstraktivne industrije
PERFORMANCE ANALYSIS OF PSEUDORANDOM ABSOLUTE POSITION ENCODER WITH EMBEDDED SERIAL PSEUDORANDOM/NATURAL CODE CONVERTER
Full text linkPseudorandom absolute position encoders represent an advanced version of the widely used absolute position encoders, particularly suitable for high-resolution angular position measurement. This paper presents a detailed performance analysis of the pseudorandom absolute position encoder with embedded serial pseudorandom/natural code converter, focusing on the maximum operating frequency and the absolute error in angular position measurement. The generalized analysis, applicable to various resolution values, represents a significant contribution of the paper. Determining the maximum operating frequency involves a detailed analysis of propagation delays in the serial code converter circuit. It is demonstrated that encoder resolution profoundly impacts performance, with a dual effect: higher resolution decreases the absolute error but also reduces the maximum operating frequency, necessitating the determination of the most suitable resolution value for each specific application. In addition to its theoretical importance, the generalized analysis aids practical application by facilitating performance calculations and the selection of the most suitable resolution for specific applications. The performance evaluation was conducted for code converters implemented using the widely used 74LVC logic circuits, considering a 6-bit converter as a representative example of converters with a single XOR logic gate in the feedback loop of the shift register, and an 8-bit converter as a representative example of serial converters with three XOR logic gates in the feedback loop. By applying the proposed analysis, the maximum clock frequency was determined to be 29.85 MHz for both resolution values (6 and 8 bits). Simulations in NI Multisim software validate the performed analysis, showing a strong correlation between simulation and theoretical results
DESIGN AND SIMULATION OF AN EFFICIENT SOLAR CELL WITH SB2SE3 AND CDTE AS DOUBLE ABSORBER LAYERS
Full text linkThe present study proposes a solar cell using double absorber layers of Sb2Se3 and CdTe. The design aim is to obtain high efficiency while maintaining or improving other main characteristics of solar cell. The proposed Sb2Se3/CdTe/CdS/ZnO/SnO2 solar cell include additional Sb2Se3 layer compared with its conventional counterpart while their total thickness is equal. The SCAPS simulator software has been applied to investigate the device performance. Firstly, the impacts of applying two absorber layers on the cell's performance and their thickness ratio were studied. Then, the effect of limitations such as band gap energy and the impurity concentration of the Sb2Se3 layer, the work function of the back contact metal, and the operating temperature on the cell performance were investigated. For thickness of 1.3 µm of Sb2Se3 layer and 0.7 µm of CdTe layer, the efficiency of 32.40% was obtained. The short circuit current density is JSC=34.55 mA/cm2, the open circuit voltage Voc = 1.06 V, and the Fill Factor is FF = 86.06%. The obtained efficiency is about 5% higher than the structure where only the layer of CdTe is applied as the absorber. Also, the use of Te which is a limited supply material in environment is reduced in proposed structure. Simulation results demonstrate that a solar cell with higher efficiency and more compatible with environment can be achieved using the proposed two absorber layer
MACHINE LEARNING-DRIVEN STATISTICAL ANALYSIS OF INDIAN RESTAURANTS: INSIGHTS FROM THE ZOMATO DATASET
Full text linkAdvances in technology and web applications, such as Zomato, have significantly transformed the restaurant industry by catering to diverse culinary preferences and offering a wide variety of food options to customers. This platform stores a vast amount of data that can be analyzed for valuable insights. The paper examines dining habits and restaurant performance through exploratory data analysis (EDA) and machine learning (ML) algorithms, helping customers find the best restaurants based on cost, ratings, location, food quality, and service. The study applies several ML models, including Linear Regression (LR), Decision Tree (DT), Random Forest (RF), Gradient Boosting (GB), XGBoost, K-Nearest Neighbors (KNN), and LASSO to the Zomato dataset. The results are evaluated using metrics such as accuracy, mean absolute error (MAE), model fit time, and model prediction time. Among these models, DT and RF show the highest predictive accuracy, with RF achieving 97.86% and outperforming other algorithms. These findings provide restaurant owners with valuable insights to enhance customer satisfaction, optimize pricing, and improve service quality. The study also demonstrates the important role of ML in the restaurant industry and suggests future opportunities for integrating real-time data, deep learning models, and sentiment analysis to offer even more precise predictions and insights
UNCERTAINTY OF THE RENEWABLE ENERGY ACCESSING THE DISTRIBUTION SYSTEM FOR OPTIMAL VOLTAGE ENHANCEMENT AND MINIMIZATION OF LOSSES USING GORILLA TROOP OPTIMIZATION
Full text linkIn recent decades, wind turbines (WT) and solar panels (PV) have been integrated into electrical power systems, particularly within power distribution networks. Given the rising energy demands and the variability of renewable energy sources, the design, operation, and control of power networks have become increasingly challenging. This research focuses on the reduction of technical losses and the enhancement of voltage levels within distribution systems by harnessing the capabilities of solid-state transformers (SST) to provide dual-reactive power support. It assesses the impact of load demands and the integration of distributed generation (DG) units, such as PV and WT, while incorporating SST into the distribution system. The study employs the K-medoid algorithm in a data-driven approach to analyze load demand, solar irradiance, and wind speed. Six test cases are formulated to evaluate the synergistic effects of combining SST with DG technologies, including wind turbines, PV arrays, and batteries. A gorilla troop optimization (GTO) algorithm is employed to determine the optimal placement and sizing of SST, WT, PV, and BES to optimize voltage levels and minimize energy losses in radial power distribution networks. To validate the results, all six cases are compared against IEEE 33 bus data from radial distribution systems, demonstrating the superior performance of the GTO approach in all cases. This study achieved a significant improvement in the voltage profile compared to the current configuration. Active power losses were cut by 82.36% thanks to the optimization of SSTs with dual reactive power support and variable DG, as opposed to the existing distribution system. Reactive power losses were also reduced by 86.36%, and the voltage profile saw a marked enhancement, rising from 0.92 p.u. to 1.0 p.u., demonstrating a substantial improvement. Reactive power usage decreased by 71.19%. The study presents a novel solution for long-standing problems related to high distribution system losses and low voltage levels by integrating SSTs with DG systems
IMPROVING EXTRACTIVE TEXT SUMMARIZATION VIA EFFICIENT COATI ALGORITHM FOR SINGLE DOCUMENT
Full text linkIn the digital era, the rapid expansion of online information demands efficient automated text summarization techniques to extract key insights from large documents. This study introduces a novel single-document extractive summarization approach that utilizes Term Frequency-Inverse Topic Frequency (TF-ITF) for feature extraction and the Coati Optimization Algorithm (COA) for optimal sentence selection. COA enhances summarization performance by balancing precision and recall through an adaptive fitness function, improving the quality of extracted summaries. The proposed model is evaluated on DUC 2002, 2003, and 2005 datasets using ROUGE, BLEU, precision, recall, and F1-score metrics. Comparative analysis against state-of-the-art optimization algorithms, including PSO, CSO, GWO, BCO, QABC, MCSO, and GLO, demonstrates that COA outperforms existing techniques, achieving higher recall and F1 scores while maintaining competitive precision. These findings establish COA as an effective optimization technique for enhancing automated text summarization