University of Niš: Facta Universitatis (E-Journals) / Универзитет у Нишу
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ASSESING THE GENERALIZED PROCESS CAPABILITY INDEX Cpyk FOR LOMAX DISTRIBUTION USING DIFFERENT ESTIMATION METHODS AND BOOTSTRAP CONFIDENCE INTERVAL
Full text linkProcess capability index is an important tool to assess the process performance used mostly in industrial areas. Many process capability indices have been proposed in the literature. In this article, we consider different estimation methods to estimate generalized process capability index, Cpyk, introduced by Maiti et al. [32] for the Lomax distribution. Maximum likelihood (ML), least squares (LS), weighted least squares (WLS), Cram´er-von Mises (CVM), Anderson Darling (AD), right-tail Anderson Darling (RAD) and maximum product of spacings (MPS) methods are used during the estimation process. Next, bootstrap confidence intervals, namely, standard bootstrap (SB), percentile bootstrap (PB), and bias-corrected percentile (BCPB) are considered to obtain 95% confidence intervals for the proposed estimators of Cpyk. The performances of proposed estimators are compared via Monte-Carlo simulation study for different parameter settings. Furthermore, we perform a simulation study to compare the coverage probabilities (CP) and average lengths (AL) of bootstrap confidence intervals. Finally, two real data sets are analyzed for an illustrative purposes
FIXED POINT RESULTS IN PARTIAL METRIC SPACES VIA INTEGRAL TYPE CONTRACTION WITH APPLICATION
Full text linkIn this paper, we derive some fixed point results via integral type contractive condition having rational terms in the setting of complete partial metric spaces and provide some consequences of the established results. Also, we give some examples in support of the established results. An application to the Fredholm integral equation is also given. Our results generalize, extend and enrich several previously published well-known fixed point results from the existing literature (see, e.g. [10], [11], [26] and many others)
ACTIVE DISTURBANCE REJECTION CONTROL AND MODEL-FREE CONTROL TUNED VIA FICTITIOUS REFERENCE ITERATIVE TUNING
Full text linkThis paper presents a comparative analysis of two data-driven algorithm combinations: the first-order Active Disturbance Rejection Control-Fictitious Reference Iterative Tuning (ADRC-FRIT) and the first-order Model-Free Control-Fictitious Reference Iterative Tuning (MFC-FRIT). The objective of both data-driven combinations is to ascertain the tunable parameters through the resolution of an optimization problem and to streamline the heuristic procedures involved. The data-driven algorithms are empirically validated through experimental trials utilizing the 3D laboratory equipment in which the x-, y-, and z-axes are controlled
SPONTANEOUS COMBUSTION PROPERTIES OF SUBMERGED COAL UNDERGOING TWO OXIDATION PROCESSES UNDER THE INFLUENCE OF HEATING SPEED
No full textTo investigate the properties of secondary oxidation (SO) and the coal spontaneous combustion (CSC) in submerged coal under varying heating rates, a Programmable Temperature-Controlled (PTC) system was employed. Analysis focused on gas concentrations, oxygen consumption rates (OCR), heat release, apparent activation energy (AAE), and constraint parameters. Results demonstrate that heating rates primarily influence the rapid oxidation stage of coal. Compared to primary oxidation (PO) at identical temperatures, SO exhibits lower oxygen consumption and OCR, but higher CO formation rates, indicating less vigorous and complete coal-oxygen reactions. During PO, AAE reaches its maximum at a heating rate of 0.5°C/min. Both SO and heating rate significantly impact CSC behavior. Their relationship during SO differs slightly from that observed during PO due to rate-dependent effects. Quantitative analysis of AAE and constraint parameters provides a comprehensive explanation of CSC characteristics under varying conditions. Crucially, CO concentration alone proves insufficient for CSC detection. Characteristic temperature points during the slow oxidation phase offer a more reliable indicator
A TOP-DOWN MULTISCALE ANALYSIS FOR DERIVING LOCAL MATERIAL PROPERTIES OF ADDITIVELY MANUFACTURED AL-SI ALLOY
Full text linkA Top-Down approach is proposed for the numerical-experimental determination of local material properties of an additively manufactured AlSi12 alloy possessing clearly expressed hierarchical structure. A thin-walled product was fabricated by wire electron beam additive technology. The alloy multiscale structure is studied experimentally by optical, scanning and transmission electron microscopy. The compression and nanoindentation mechanical tests are carried out. Based on the experimental data, the finite element models of a layered structure at the macrolevel, dendritic and composite cellular structures at the mesolevel, and a composite structure comprising an aluminum matrix and silicon particles at the microlevel are created. The proposed Top-Down analysis assumes sequential macro-meso-micro structure-based numerical simulations to derive the mechanical properties of aluminum in dendrites at the microlevel and aluminum in the eutectic at the submicron level. The stress concentration and the plastic strain localization in dendritic, cellular and composite structures are analyzed. It was found at the mesoscale that the eutectic material experiences more shear stresses than the aluminum dendrites, with the highest stresses being observed in between the closely located dendrites. The volumetrically tensile and pure shear regions, as well as the regions of low elastic strains, are found after 30% compression
NEKI ASPEKTI PREVOĐENJA LITERATURA IZ OBLASTI MUZIKE SA ENGLESKOG NA SRPSKI JEZIK
No full textEnglish is, so to speak, the lingua franca of musicology today. While knowing German, French, Spanish, or other languages is certainly appreciated, especially for scholars from non-English-speaking backgrounds, it has become nearly impossible to pursue a scientific career in this field without a strong command of English. But what about those who are not professionals or experts, yet still wish to explore the history of music, its compositions, and their creators in their own language? They often rely on translations of books, whose content is not always faithful to the original. For instance, an analysis of the book Classical Style – Haydn, Mozart, Beethoven by Charles Rosen (Belgrade, Nolit, 1979), which has been a key text on 18th-century music in Serbia for decades, reveals numerous translation errors. These include formulations with inaccurate or awkward expressions, which sometimes verge on the absurd. Why is it important to translate books from foreign languages into the "local" language? How crucial is it for translators to be familiar with the specialized field the book addresses? Which publishing houses in Serbia are committed to translating publications on music? These are some of the questions this paper aims to address.Engleski je danas – mogli bismo reći – lingua franca muzikologije. Iako je poznavanje nemačkog, francuskog, španskog ili bilo kog drugog jezika dobrodošlo, naročito za istraživače koji dolaze iz zemalja gde se ne govori engleski, bez čvrstog poznavanja engleskog jezika gotovo je nemoguće razviti naučnu karijeru u ovoj oblasti. Ali šta je sa onima koji nisu profesionalci ili eksperti, a ipak žele da čitaju o istoriji muzike, kompozicijama i njihovim autorima na svom jeziku? Oni čitaju prevode knjiga čiji sadržaj nije uvek dosledan originalu. Analiza publikacije Classical Style – Haydn, Mozart, Beethoven Čarlsa Rozena (Beograd, Nolit, 1979), na primer, koja se decenijama koristi kao važna literatura o muzici 18. veka u Srbiji, otkrila je brojne nedostatke u prevodu. Postoje formulacije koje sadrže mnoge netačne ili nezgrapne izraze čije se značenje gotovo graniči sa karikaturom. Ova izjava nije data s namerom da se kritikuje prevod urađen pre pola veka, već da se skrene pažnja na potrebu za većim fokusom na prevođenje literature o muzici u našoj zemlji. Iskustvo pokazuje da se u poslednjim decenijama u Srbiji uglavnom prevode starija izdanja knjiga, zbog isteka autorskih prava i finansijske održivosti takvih projekata. Plaćanje autorskih prava za aktuelne publikacije često je nerentabilno za tiraže malih zajednica zainteresovanih za muziku. Međutim, starije knjige o muzici nose 'teret' jezika koji je 'star' ili čak ideološki 'teret' u svom sadržaju. U Srbiji postoji vrlo malo izdavačkih kuća koje su fokusirane na izdavanje knjiga o muzici. Kao studije slučaja treba pomenuti Službeni glasnik, koji je državni izdavač, i Studio lirica, koji je privatno finansiran. Ove kuće nedavno su izdale desetine 'muzičkih' knjiga u prevodu, uglavnom starijih datuma. Prevodioci u tim knjigama su stručnjaci koji su pre svega muzički obrazovani, bez obzira na njihovo znanje engleskog jezika. U nekima od njih, čak i u samom naslovu, mogu se primetiti jezičke nejasnoće ili gramatičke greške. Ipak, ovo su vredni koraci ka obezbeđivanju knjiga o muzici u našoj zemlji. Uprkos svim naporima da se knjige o muzici prevedu na srpski, mora se naglasiti da su sadržaji iz nekih oblasti teško prevodivi. To je slučaj sa muzičkom semiotikom, na primer, čija je terminologija izuzetno složena čak i na engleskom, zbog čega je njen prevod gotovo nemoguć. A kada već govorimo o prevodima muzičkih knjiga, nije ništa manje važno izdavanje naučnih dela iz oblasti muzikologije naših stručnjaka na srpskom, a ne na engleskom jeziku. Strogi zahtevi naučne zajednice za citiranošću u međunarodno priznatim naučnim časopisima ponekad smanjuju 'prostor za manevrisanje' istraživačima koji žele da objavljuju na svom jeziku. Promocija nauke na lokalnom jeziku ostvaruje se i kroz njenu produkciju. To su važni aspekti muzikološke aktivnosti koji ne treba da se zanemaruju u kontekstu govora o prevođenju knjiga u oblasti muzike
DIGITALNA TRANSFORMACIJA MUZIČKOG OBRAZOVANJA: POTENCIJALI INTERNET MUZIČKIH STVARI I PAMETNIH MUZIČKIH INSTRUMENATA U SAVREMENOJ NASTAVI
No full textIn the context of accelerated globalization and the Fourth Industrial Revolution, music education is becoming increasingly reliant on digital technologies. This paper presents the concept of the Internet of Musical Things (IoMusT) and the application of smart musical instruments in school teaching through a review of relevant literature. Key technological elements including pressure and motion sensors, wireless connectivity (Wi‑Fi, Bluetooth), cloud and edge computing architectures, and AI‑driven “microlearning” algorithms are described, showing how they collectively enable personalized practice, immediate feedback, and synchronized virtual ensemble performance. A dedicated section explores inclusive IoMusT applications, such as haptic interfaces and robotic gloves that support students with motor or sensory impairments, as well as the integration of brain activity analysis (fNIRS) for monitoring cognitive load. Through data driven analytics and GDPR compliant anonymization protocols, the paper demonstrates reductions in practice time, significant enhancements in social and metacognitive skills, and increased student motivation and autonomy. Identified challenges such as high costs, the need for teacher training, and ethical privacy concerns are addressed through proposed solutions: “instrument-as-a-service” financing models, modular micro‑credential programs for AI-supported teaching, and privacy-by-design practices. Finally, the study offers practical recommendations for the interoperable, ethically grounded, and pedagogically empowering integration of IoMusT technologies into music curricula across all educational levels. This article has been retracted. Link to the retraction https://doi.org/10.22190/FUTLTE251014013EU uslovima ubrzane globalizacije i četvrte industrijske revolucije, muzičko obrazovanje sve više zavisi od digitalnih tehnologija. Ovaj rad objašnjava koncept Interneta muzičkih stvari (IoMusT) i primenu pametnih muzičkih instrumenata u školskoj nastavi kroz pregled relevantne literature. Opisani su ključni tehnološki elementi, senzori za pritisak i pokret, bežične veze (Wi‑Fi, Bluetooth), cloud i edge‑computing arhitekture, te AI algoritmi za “mikroučenje”, koji zajedno omogućavaju personalizovane vežbe, neposredne povratne informacije i sinhronizovano virtuelno ansambl‑sviranje. Poseban deo rada posvećen je inkluzivnim primenama IoMusT‑a, uključujući haptičke interfejse i robotske rukavice za podršku učenicima s motoričkim ili senzornim poteškoćama, kao i integraciji analiza moždane aktivnosti (fNIRS) u praćenje kognitivnog opterećenja. Kroz podacima vođenu analitiku i GDPR kompatibilne smernice za anonimnost podataka, rad ukazuje na skraćenje vremena vežbanja, značajno jačanje socijalnih i metakognitivnih veština, te veću motivaciju i samostalnost učenika. Identifikovani su izazovi, visoki troškovi, potreba za obukom nastavnika i etička pitanja privatnosti, kao i moguća rešenja: modeli finansiranja “instrument kao usluga”, modularni programi mikro‑sertifikata za AI podržano podučavanje i etičke prakse “privatnost po dizajnu”. Na kraju, rad nudi praktične preporuke za interoperabilnu, etički utemeljenu i pedagogijski osnažujuću integraciju IoMusT tehnologija u muzičke kurikulume na svim obrazovnim nivoima
IN RESPECTFUL MEMORY OF PROFESSOR ZORAN JAKŠIĆ
Full text linkZoran Jaksic passed away on January 31, 2025, leaving a deep mark on the scientific community at both the national and international levels.Zoran Jakšić was born on April 14, 1960, in Pančevo, where he completed his primary and secondary education. He graduated from the Faculty of Electrical Engineering, University of Belgrade, Department of Technical Physics. He received his master's and doctorate degrees from the Faculty of Electrical Engineering, University of Belgrade, Department of Physical Electronics.He spent his scientific and research career in Serbia. From 1983 to 1987, he worked in the development department of the "Utva" aircraft factory in Pančevo. In 1987, he moved to the Institute of Chemistry, Technology and Metallurgy, University of Belgrade, where he worked at the Center for Microelectronic Technologies. He was the coordinator for science and deputy head of the Center for Microelectronic Technologies (2011-2018). He significantly contributed to the Center's accreditation as a national Center of Excellence in 2014
SOLITARY AND TRAVELING WAVE SOLUTIONS TO NEMATIC LIQUID CRYSTAL EQUATIONS WITH CUBIC-QUINTIC NONLINEARITY USING THE JACOBI ELLIPTIC FUNCTION EXPANSION METHOD
Full text linkIn this paper, the Jacobi elliptic function (JEF) expansion method is applied to the system of equations governing nematic liquid crystals with a cubic-quintic nonlinearity. Solutions that are first order polynomials of the JEFs for the wave function and second order for the angle function are obtained. The solutions impose constraints on only two parameters and include a wide range of functions. Both solitary and traveling wave solutions are possible, as well as solutions both with and without chirp
CLASSIFICATION OF SPORTS VIDEOS BY COMBINING RESNET50 MODEL AND FINE TUNING
Full text linkThis article represents a classification of sports videos by integrating the ResNet50 model and fine-tuning methods. Broadcasting companies give significant importance to the classification of sports videos. That is a subclass of recognition of human action, which will clarify the context of videos. This work uses a deep neural network-based ResNet50 model with a fine-tuning technique for classifying popular sports types in India into their corresponding classes. This paper considers 14 main sports - badminton, basketball, boxing, cricket, football, hockey, kabaddi, swimming, shooting, table tennis, tennis, volleyball, weight lifting, and wrestling. The dataset is created to focus on sports action-based classification. Fine-tuning is nothing but networking surgery. First, a pre-trained Convolutional Neural Network model will be loaded, and then fine-tuning (network surgery) will be applied. The base model (ResNet50) will be frozen, so it will not be trained via backpropagation. After fine-tuning, the classifier will be ready to correctly classify a sports video into its category. The training accuracy of the proposed classifier is 91.73%, and testing is done on sports videos. The classifier classifies each sports video into its class correctly. A descent confusion matrix has been pertained