Bulletin of Natural Sciences Research
type: channel
publisher: Faculty of Sciences and Mathematics, University of Priština in Kosovska Mitrovica, Serbia
language: en
publication name: Bulletin of Natural Sciences Research
issn: 2738-0971
copyright: Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
items: PERFORMANCE, ACCURACY, AND PREDICTIVE CHUNK OPTIMIZATION OF PARALLEL SIMPSON AND TRAPEZOIDAL INTEGRATION METHODS
items: MINERALOGICAL COMPOSITION AND PROPERTIES OF PELOID FROM DUČEVAC, SERBIA, TRADITIONALLY APPLIED TO HAIR TREATMENT
items: GEOHERITAGE SITES IN THE TERRITORIAL UNIT “NORTH OF THE AUTONOMOUS PROVINCE OF KOSOVO AND METOHIJA”
items: A MODULAR IOT PLATFORM FOR NEXT-GENERATION SMART HOMES: ARCHITECTURE, REAL-TIME CONTROL, AND EDGE AI READINESS
items: HYBRID BLE–PDR LOCALIZATION SYSTEM FOR SMART RETAIL ENVIRONMENTS
items: BIOACCUMULATION OF HEAVY METALS IN THE ROMAN SNAIL (HELIX POMATIA) IN THE AREA OF KOSOVSKA MITROVICA
items: AN INFORMATION-PHYSICAL PERSPECTIVE ON FADING PROCESS TRANSITIONS BASED ON HIGHER ORDER STATISTICS
items: AN APPLICATION OF RESIDUE NUMBER SYSTEM ARITHMETICS TO SECURE HASH FUNCTIONS DESIGN
items: OPTIMIZATION OF FLUID VOLUME CONTROL IN HEMODIALYSIS USING FEDERATED LEARNING
items: OPTIMIZATION OF TOKENIZATION AND MEMORY MANAGEMENT FOR PROCESSING LARGE TEXTUAL CORPORA IN MULTILINGUAL APPLICATIONS
items: AN IMPROVED CANOPY INTERCEPTION SCHEME INTO BIOGEOCHEMICAL ANALYSIS OF WATER FLUXES IN SUBALPINE CONIFEROUS FOREST (NORTHERN ITALY)
items: SPECIFICITY OF GEOGRAPHICAL CONTENT FOR THE APPLICATION OF DEBATE IN GEOGRAPHY LESSONS
items: EXPLORING THE NEXUS OF TOURISM DEVELOPMENT, COMMUNITY PERCEPTIONS, AND SUSTAINABILITY IN PROTECTED AREAS
items: STRUCTURAL AND ELECTROCHEMICAL PROPERTIES OF SYNTHESIZED NANOSTRUCTURED Ca0.9Er0.1MnO3 BY HYDRAZINE NITRITE PROCEDURE
items: ASSESSMENT OF THE MEDICINAL PROPERTIES AND COMPONENTS OF THE BLEND OF THREE INDIGENOUS ESSENTIAL OILS (Syzygium aromaticum, Monodora myristica, AND Xylopia aethiopica) FROM AFRICA
items: DIGITALIZATION IN THE TOURISM INDUSTRY: IMPACTS ON EMPLOYMENT, JOB SATISFACTION, AND CAREER DEVELOPMENT
items: RADON IN WATER FROM PRIVATE WELLS AND ITS CONTRIBUTION TO INTERNAL EXPOSURE OF POPULATION IN RURAL AREAS AT TOPLICA REGION, SOUTHERN SERBIA
items: APPLICATION OF COMPRESSIVE SENSING TECHNIQUES FOR ADVANCED IMAGE PROCESSING AND DIGITAL IMAGE TRANSMISSION
items: RESTRICTED AND EXTENDED THETA OPERATIONS OF SOFT SETS: NEW RESTRICTED AND EXTENDED SOFT SET OPERATIONS
items: THE RELATIONSHIP BETWEEN GEODIVERSITY AND BIODIVERSITY – A THEORETICAL APPROACH
items: THE INHIBITION OF ACNE PROTEASE BY SOME FLAVONES: DFT, SWISSADMET AND MOLECULAR DOCKING
items: ANALYSIS OF THE SELF-SUFFICIENCY OF WHEAT PRODUCTION IN BOSNIA AND HERZEGOVINA
items: EVALUATING THE INFLUENCE OF TRYPANOSOMIASIS ON MURINE MODEL USING Corchorus olitorius LEAF EXTRACT AS A TRYPANOCIDAL AGENT
items: ASSESSMENT OF HEAVY METALS IN FISH AND SEDIMENTS FROM RIVER MTAKUJA IN THE VICINITY OF A GOLD MINE IN TANZANIA
items: ON THE SECOND ORDER STATISTICS OF THE RATIO OF TWO FISHER-SNEDECOR RANDOM VARIABLES AND ITS APPLICATION TO INTERFERENCE LIMITED COMMUNICATIONS
items: OPTIMIZATION OF THE 2P FIFTH DEGREE CONVOLUTION KERNEL IN THE SPECTRAL DOMAIN
items: DETERMINATION OF POLYPHENOL AND FLAVONOID CONTENT AND ANTIOXIDANT ACTIVITY OF ETHANOLIC, CHLOROFORM AND ETHYL ACETATE EXTRACT OF THE PLANT SPECIES Thymus serpyllum L.
items: RECORDS OF LICHEN SPECIES FROM GENUS ACAROSPORA, NEW FOR SERBIA, SOUTHWEST BALKAN PENINSULA
items: NOMA COOPERATIVE RELAYING SYSTEMS OVER RICIAN-SHADOWED FADING CHANNELS
items: NEW PROOF OF AHLFORS LEMMA ABOUT GREEN STOKES FORMULA FOR DISTRIBUTIONS

PERFORMANCE, ACCURACY, AND PREDICTIVE CHUNK OPTIMIZATION OF PARALLEL SIMPSON AND TRAPEZOIDAL INTEGRATION METHODS
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description: Parallel numerical integration is a fundamental component of many scientific and engineering applications, yet its performance depends strongly on workload partitioning strategies. In shared-memory environments, the choice of chunk size directly affects load balancing, scheduling overhead, and cache utilization, particularly when adaptive numerical methods are employed. This paper presents an analysis of the performance, accuracy, and scalability of four numerical integration techniques: Simpson’s rule, Adaptive Simpson’s rule, the Trapezoidal rule, and the Adaptive Trapezoidal rule, implemented in a multi-threaded execution model. Execution-time distributions are analyzed across a wide range of chunk sizes and thread counts, revealing substantial performance variability and method-dependent optimal chunk configurations. In addition to performance evaluation, numerical accuracy is assessed to highlight trade-offs between computational efficiency and error reduction. Based on empirical observations, optimal chunk ranges are identified and used to construct a predictive model that estimates near-optimal chunk configurations as a function of the number of threads. The proposed approach enables efficient parameter selection without exhaustive tuning and demonstrates the feasibility of predictive chunk optimization for parallel numerical integration.
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creator: Sanja Đurović
creator: Marko Smilić
creator: Časlav Stefanović
creator: Stefan Panić
creator: Milan Savić
rights: Copyright (c) 2026 Bulletin of Natural Sciences Research
date: 2026-04-21
publication date: 2026-04-21
doi: 10.5937/bnsr16-64069

MINERALOGICAL COMPOSITION AND PROPERTIES OF PELOID FROM DUČEVAC, SERBIA, TRADITIONALLY APPLIED TO HAIR TREATMENT
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description: This study analyzes mineralogical composition and properties of two samples sourced from Dučevac, Serbia, which are traditionally used in hair treatment. This investigation provides the first systematic, multidisciplinary characterization of the specified material, comparing the samples with respect to their mineralogical phases, chemistry, and physicochemical properties. Notably, sample 1.1 is primarily calcite, with a smaller amount of clay minerals (illite, kaolinite, and smectite). In contrast, sample 1.2 showcases a blend of illite and quartz, with small amounts of other clay minerals (smectite, kaolinite, chlorite) and plagioclase. Sample 1.1 has higher amounts of CaO (9.83 wt.%) and Na2O (2.97 wt.%) than sample 1.2; in return, sample 1.2 has higher amounts of Fe2O3 (4.25 wt.%) and MgO (4.61 wt.%). In terms of pH, both samples are moderately acidic, with CEC values ranging from 8 to 9 meq/100g, and SSA measurements between 66 and 75 m²/100g. The color also reflects distinct variations, with sample 1.1 registering at 583 nm and sample 1.2 at 573 nm. All analytical values align with reference peloids found in literature, enhancing our understanding of the samples' characteristics and origins. This highlights the material's geological significance and the importance of preserving traditional practices as part of the region's geoheritage.
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creator: Maja Roksić
creator: Alena Zdravković
creator: Predrag Dabić
creator: Milena Rosić
creator: Nenad Nikolić
creator: Maria Čebela
creator: Dragana Jordanov
rights: Copyright (c) 2026 Bulletin of Natural Sciences Research
date: 2026-03-22
publication date: 2026-03-22
doi: 10.5937/bnsr16-64746

GEOHERITAGE SITES IN THE TERRITORIAL UNIT “NORTH OF THE AUTONOMOUS PROVINCE OF KOSOVO AND METOHIJA”
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description: This paper presents an assessment of geoheritage sites in the territorial unit “North of the Autonomous Province of Kosovo and Metohija”, with the objective of identifying their scientific, educational, landscape–aesthetic, conservation, functional, and tourism values. The assessment of geoheritage sites was carried out using the Geosite Assessment Model (GAM), which enables an integrated, quantitative evaluation. The analysis encompassed five representative geoheritage sites and was based on data obtained from relevant scientific literature and field investigations. The results demonstrate that all analyzed sites exhibit medium to high values for the main indicators, confirming their considerable geoheritage potential. In contrast, the additional values are predominantly moderate, primarily due to insufficient protection measures, limited promotion, and underdeveloped tourism infrastructure. The identified imbalance between the main values and the level of their valorization underscores the need for a systematic and integrated approach to geoheritage management.
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creator: Dragan Petrović
rights: Copyright (c) 2026 Bulletin of Natural Sciences Research
date: 2026-03-22
publication date: 2026-03-22
doi: 10.5937/bnsr16-64387

A MODULAR IOT PLATFORM FOR NEXT-GENERATION SMART HOMES: ARCHITECTURE, REAL-TIME CONTROL, AND EDGE AI READINESS
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description: Rapid technological progress and increasingly pressing needs for energy efficiency, safety, and personalised comfort have driven the development of intelligent systems for residential automation. This paper presents the design and implementation of a modular IoT smart-home system based on a microcontroller architecture with real-time data processing. The developed prototype integrates sensor modules for detecting temperature, humidity, air quality, illuminance, vibration, precipitation, and flame, as well as actuators for automated control of windows, doors, lighting, ventilation, and alarm mechanisms. The system is connected to a mobile application that enables monitoring and interactive control in real time, and users can define scenarios such as “night mode” or “away mode”. Special emphasis in the design is placed on the system’s modularity, its energy optimisation, and the ability to adapt behaviour based on historical data and user habits. The system’s functionality was tested on a physical model and in real conditions, establishing that it reacts within a time window of 1–3 seconds from the moment a change in environmental parameters is detected. The obtained results indicate significant potential for integrating microcontrollers, an IoT platform, and adaptive control algorithms in the domain of smart buildings and future concepts of urban automation. The paper also opens up avenues for further development with integrated machine-learning and artificial-intelligence algorithms aimed at achieving fully autonomous control of the residential environment. This iteration includes a fully functional physical prototype and application, while the predictive AI part is evaluated offline via simulation/emulation based on recorded logs, without on-device inference.
subject: Original Scientific Paper
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creator: Nebojša Andrijević
creator: Zoran Lovreković
creator: Bojan Jovanović
creator: Milica Stojičević
creator: Milica Velkovski
rights: Copyright (c) 2026 Bulletin of Natural Sciences Research
date: 2026-01-22
publication date: 2026-01-22
doi: 10.5937/bnsr16-61990

HYBRID BLE–PDR LOCALIZATION SYSTEM FOR SMART RETAIL ENVIRONMENTS
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description: Accurate indoor user localization is a key component in the development of cashier-free smart stores, enabling advanced customer experiences, security monitoring, and behavioral flow analysis. This paper presents a hybrid localization approach that combines inertial motion tracking (Pedestrian Dead Reckoning – PDR) with Bluetooth Low Energy (BLE) tag signals. Unlike systems that require dedicated infrastructure, the proposed solution uses existing BLE electronic shelf labels (ESLs) as reference points. Their identification signals are used to correct the PDR drift, thereby reducing the cumulative error typical of purely inertial methods. The mobile application continuously measures the Received Signal Strength Indicator (RSSI) from BLE tags and applies threshold-based position corrections, while the PDR module, based on the Scarlett step-length model, maintains continuous tracking between tags. The system additionally integrates map-based spatial constraints that eliminate physically impossible paths through a particle-filter mechanism. Experimental evaluation in a retail environment demonstrated an average error of 0.4 m for linear movement and 1.3 m for a complex circular trajectory, confirming meter-level localization accuracy without the need for cloud processing. All computations are performed locally on the user’s device, ensuring privacy protection and enabling real-time movement analysis and context-aware retail interaction.
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creator: Nebojša Andrijević
creator: Zoran Lovreković
creator: Bojan Jovanović
creator: Vladan Radivojević
creator: Nenad Živanović
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-12-12
publication date: 2025-12-12
starting page: 86
ending page: 93.
doi: 10.5937/bnsr15-62101

BIOACCUMULATION OF HEAVY METALS IN THE ROMAN SNAIL (HELIX POMATIA) IN THE AREA OF KOSOVSKA MITROVICA
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description: The bioaccumulation of heavy metals in the Roman snail (Helix pomatia Linnaeus, 1758) was investigated in October 2024. Animals were sampled at the location "Gornje Polje," which is situated near the former "Trepča" plant. The snails were collected by hand and then transported to the laboratory. A total of 34 medium-aged snails and 36 older snails were collected. The snails were dissected, and the content of heavy metals determined in the hemolymph, hepatopancreas, kidney and shell. In addition to analyzing the heavy metal content in the snails, an analysis of the heavy metals content in the soil was performed. The soil was collected in a quantity of 1 dm³ using a shovel and transported to the laboratory. The content of seven elements was examined: Arsenic (As), Copper (Cu), Iron (Fe), Cadmium (Cd), Manganese (Mn), Lead (Pb), and Zinc (Zn). The highest level of accumulation is heavy metal observed in the hepatopancreas. Furthermore, other structures exhibit a significantly high level of accumulation. All of this suggests that snails are a highly useful tool for diagnostic purposes in environmental of heavy metal accumulation. The analysis of heavy metal content was performed at the Public Health Institute of Kosovska Mitrovica.
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creator: Željko Bulatović
creator: Tatjana Jakšić
creator: Maja Pavlović
creator: Nikola Bačević
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-09-23
publication date: 2025-09-23
starting page: 1
ending page: 8.
doi: 10.5937/bnsr15-57799

AN INFORMATION-PHYSICAL PERSPECTIVE ON FADING PROCESS TRANSITIONS BASED ON HIGHER ORDER STATISTICS
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description: This paper proposes a novel theoretical framework for analyzing fading channels by introducing the concepts of energetic orbits and entropy barriers. Inspired by atomic physics and thermodynamic analogies, here the signal envelope is modeled as a stochastic process whose transitions between different structural regimes (extrema, inflection points, level crossings) correspond to energy quantization events. Each transition is associated with a local information-energy quantum, defined as a product of amplitude displacement and transition count, normalized by local entropy. Furthermore, the ideas of entropic spin and degeneracy of states have been explored, and the dispersion of level-crossing processes, extremum-crossing process, inflection point-crossing process, saddle point-crossing process (LCR, ECR, ICR, SCR) through an autocorrelation-based energetic formalism has been characterized. This approach enables the construction of a layered energetic map of fading dynamics and offers new insights into the structural behavior of wireless signals under stochastic fluctuations.
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creator: Stefan Panić
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-10-09
publication date: 2025-10-09
starting page: 78
ending page: 85.
doi: 10.5937/bnsr15-59743

AN APPLICATION OF RESIDUE NUMBER SYSTEM ARITHMETICS TO SECURE HASH FUNCTIONS DESIGN
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description: This paper presents a cryptographic hash function based on the Residue Number System (RNS), designed to enhance security and computational efficiency. The function leverages the parallelism and modular properties of RNS to achieve high-speed processing while maintaining strong diffusion and resistance to various cryptanalytic attacks. Experimental results confirm that the proposed function exhibits a pronounced Avalanche effect, ensuring that minor changes in the input result in significant alterations in the hash output. Additionally, statistical analysis using the ENT test demonstrates a high level of entropy and uniform distribution of hash values, reinforcing the function’s unpredictability—an essential characteristic for cryptographic security. The proposed hash function is suitable for applications in digital signatures, data integrity verification, and authentication systems, offering advantages in environments requiring high computational efficiency.
subject: Original Scientific Paper
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creator: Milija Pavlović
creator: Stefan Panić
creator: Boris Damjanović
creator: Negovan Stamenković
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-06-11
publication date: 2025-06-11
starting page: 72
ending page: 77.
doi: 10.5937/bnsr15-58114

OPTIMIZATION OF FLUID VOLUME CONTROL IN HEMODIALYSIS USING FEDERATED LEARNING
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description: Overhydration (OH) represents a significant challenge for hemodialysis patients, significantly affecting the outcomes of their treatment. Accurate prediction and management of overhydration are key to optimizing therapy and improving patients' quality of life. The aim of this paper is to present a federated learning (FL)-based approach designed to predict overhydration in hemodialysis patients, using a dataset comprising different clinical and bioimpedance parameters. Federated learning enables collaborative learning from multiple data sources while preserving the privacy and security of individual patient data. Research results show that federated learning has the potential as an effective tool for predictive modeling in clinical settings. The developed models achieve high performance in overhydration estimation, with metrics confirming their accuracy and reliability. The proposed approach achieved a R² of 0.9999999, a MAE of 0.00018 and an MSE of 0.0031, demonstrating its predictive strength and practical applicability. This study highlights the advantages of federated learning in using distributed data to advance predictive capabilities in healthcare. By overcoming challenges related to privacy and data security, the approach presented in this paper opens up opportunities for more personalized and accurate prognoses, potentially improving decision-making and patient care in hemodialysis.
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creator: Suzana Đorđević
creator: Stefan Ćirković
creator: Danijela Milošević
creator: Milan Gligorijević
creator: Vladimir Mladenović
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-03-02
publication date: 2025-03-02
starting page: 65
ending page: 71.
doi: 10.5937/bnsr15-55563

OPTIMIZATION OF TOKENIZATION AND MEMORY MANAGEMENT FOR PROCESSING LARGE TEXTUAL CORPORA IN MULTILINGUAL APPLICATIONS
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description: Optimization of tokenization and memory management in processing large datasets represents a key challenge in the contemporary development of language models. This paper focuses on enhancing the processing of large textual corpora in Serbian using the GPT-2 model, specifically adapted for transfer learning. Tokenization optimization was achieved by adding language-specific tokens for Serbian, while memory management was improved through advanced resource management methods during training. Key findings demonstrate significant memory consumption reduction and training process acceleration, enabling more efficient utilization of available computational resources. This research contributes to the development of language models tailored for the Serbian language and provides a foundation for further studies in the field of natural language processing (NLP). The implications of this work are multifaceted: it facilitates more efficient creation of NLP applications for Serbian-speaking regions, enhances the accuracy and performance of language models, and opens opportunities for applications across various domains, from automated translation to sentiment analysis. This study paves the way for future research focusing on additional optimization of language models, including adaptation for other languages with similar characteristics, as well as exploring new methods for even more efficient memory management during large-scale textual data processing.
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creator: Dejan Dodić
creator: Dušan Regodić
creator: Nikola Milutinović
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-02-06
publication date: 2025-02-06
starting page: 56
ending page: 64.
doi: 10.5937/bnsr15-54993

AN IMPROVED CANOPY INTERCEPTION SCHEME INTO BIOGEOCHEMICAL ANALYSIS OF WATER FLUXES IN SUBALPINE CONIFEROUS FOREST (NORTHERN ITALY)
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description: The delicate ecosystems of the Alps' subalpine forests are crucial to water supplies as well as the local and mesoscale climate regulators. Although earlier research has assessed various aspects of the water balance, there is currently a dearth of studies that directly measure every component of the water budget. Furthermore, little is understood about the frequency and impact of fog as well as how forest layout affects water balance. Using the eddy covariance technique, sap flow sensors, phenocam images, throughfall and stemflow gauges, soil moisture sensors, water discharge measurements, and a fog interception gauge, we carried out a thorough investigation of a subalpine coniferous forest at the Renon site in the Italian Alps. Furthermore, we measured the leaf area and lichen occurrence as possible canopy water storage components. Large amount of precipitation was reflected by the canopy interception in spruce and coniferous forest. Although fog alone had no effect on total water intake, it did result in a tiny but noticeable increase in throughfall during mixed fog and rain precipitation events, however this effect seemed to be less significant than in cloud forests that are tropical or subtropical. At the catchment level, the annual balance (November–October) was almost perfectly closed when all input and output components were taken into account. This paper contributes to the ecological monitoring of the Alpine forests in South Tyrol, Northern Italy.
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creator: Polina Lemenkova
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-07-21
publication date: 2025-07-21
starting page: 48
ending page: 55.
doi: 10.5937/bnsr15-57655

SPECIFICITY OF GEOGRAPHICAL CONTENT FOR THE APPLICATION OF DEBATE IN GEOGRAPHY LESSONS
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description: Modern geography teaching involves a more intensive use of methods designed to encourage students to learn with reason, to think reasonably and to draw independent conclusions. One of the methods that can contribute to achieving the above goals is certainly the use of debate and its increased implementation in geography lessons. Debating is a form of dialogic method that involves a discussion between two teams and the exploration of a given topic through argumentative practice. The paper analyzes the content of geography lessons that can be learned through debating and its application in the classroom from a theoretical and practical perspective. The first part of the paper is devoted to the theoretical foundations of teaching methods, the conceptual definition of debate, the Karl Popper format and the rules that should be applied in classroom practice. The second part of the paper deals with the application of debate in geography lessons using a content analysis with concrete examples from the subject. The results of the paper show the importance of debate for the development of skills that students in Serbia lack, including argumentative reasoning, public speaking, collaboration and research skills.
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creator: Ivana Đorđević
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-04-13
publication date: 2025-04-13
starting page: 42
ending page: 47.
doi: 10.5937/bnsr15-56225

EXPLORING THE NEXUS OF TOURISM DEVELOPMENT, COMMUNITY PERCEPTIONS, AND SUSTAINABILITY IN PROTECTED AREAS
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description: Sustainable tourism integrates economic, social, and environmental aspects of sustainability. This study investigates the local community’s perceptions of tourism development impacts and factors influencing support for sustainable tourism and destination sustainability within Stara Planina Nature Park. Using a Structural Equation Modeling (SEM) approach, using multiple hypothesized relationships across key dimensions, including economic, environmental, social, and infrastructural impacts are examined. The findings highlight the importance of socio-cultural factors in fostering support, while also recognizing the negative impact of environmental and infrastructural concerns. Socio-cultural impacts significantly and positively influenced support for sustainable tourism and destination initiatives, highlighting the role of cultural exchange, tradition preservation, and community identity in garnering local support. These findings align with previous studies, emphasizing the importance of perceived socio-cultural benefits in fostering community backing for tourism development. Effective STD management requires the active involvement of local stakeholders to ensure alignment with local values and environmental goals. Policymakers should focus on enhancing socio-cultural benefits, addressing infrastructural challenges, and effectively communicating economic advantages. Limitations of the study include its cross-sectional design, suggesting the need for longitudinal research to better understand the evolving impact of tourism.
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creator: Sanja Obradović Strålman
creator: Nikola Milentijević
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-02-06
publication date: 2025-02-06
starting page: 34
ending page: 41.
doi: 10.5937/bnsr15-55046

STRUCTURAL AND ELECTROCHEMICAL PROPERTIES OF SYNTHESIZED NANOSTRUCTURED Ca0.9Er0.1MnO3 BY HYDRAZINE NITRITE PROCEDURE
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description: Synthesis, structural, and electrochemical properties of nanostructured powders Ca0.9Er0.1MnO3 with perovskite-type crystal were studied. Nanopowders were prepared by the combustion method using the hydrazine nitrite procedure (HNP), which involves mixing metal nitrate salts (Ca, Mn, Er) in a stoichiometric ratio and varying the quantity of added hydrazine. In this synthetic procedure, the aim is to adjust the amount of hydrazine in order to control the combustion of the reactions, obtain the required amount of fuel energy, but also the amount that will complex the reactants in the mixture. The powders obtained by hydrazine nitrate synthesis were then calcined for 15 minutes at temperatures of 800, 900, and 1000 °C. Characterization of the synthesized and calcined samples was performed using advanced techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and electrochemical measurements. The results clearly indicate that the amount of hydrazine added is crucial in preparing the Ca0.9Er0.1MnO3 sample. This highlights the importance of precise hydrazine dosage in optimizing the synthesis process to enhance the material's properties. Further, the electrochemical properties of the obtained perovskite nanopowders were investigated by cyclic voltammetry (CV) and electrochemical spectroscopic impedance (EIS) on perovskite-modified carbon paste electrodes. Electrochemical measurements showed improved electrochemical properties of perovskite-modified carbon paste electrodes compared to bare carbon paste electrode (CPE). The electrode modified with the material synthesized with the smallest amount of hydrazine presented the best results.
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creator: Tijana B. Vlašković
creator: Milena Rosić
creator: Branka B. Petković
creator: Bojana B. Laban
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-12-25
publication date: 2025-12-25
starting page: 27
ending page: 33.
doi: 10.5937/bnsr15-61823

ASSESSMENT OF THE MEDICINAL PROPERTIES AND COMPONENTS OF THE BLEND OF THREE INDIGENOUS ESSENTIAL OILS (Syzygium aromaticum, Monodora myristica, AND Xylopia aethiopica) FROM AFRICA
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description: The essential oils of Syzygium aromaticum, Monodora myristica, and Xylopia aethiopica have been used widely in Africa for medicinal purposes. This work is aimed at finding out the combined medicinal efficacy of the three essential oils. The crude EOs were extracted by the hydrodistillation method. The chemical components were determined by GC-MS analysis. The phytochemicals, antidiabetic, anti-inflammatory, and antioxidant activities were determined by standard analytical methods. The GC-MS analysis indicated eugenol (75.08%) as the major component in the EO of S. aromaticum, isocaryophyllene (29.36%) in the EO of M. myristica, isospathulenol (8.67%) in the EO of X. aethiopica, and eugenol (34.25%) in the blend of the EOs. The phytochemicals in all the EOs and the blend were at varying values. α-amylase and α-glucosidase inhibition showed that the EO blend with an IC50 value of 1250.69 µg/mL and 1080.56 µg/mL, respectively, had the highest inhibition compared with other EOs. S. aromaticum had the highest activity against the anti-inflammatory indicators. The least inhibitory activity for DPPH was recorded with M. myristica EO. S. aromaticum recorded the highest inhibitory efficacy against ABTS and nitric oxide assays, respectively. The blend recorded the highest inhibitory activity against lipid peroxidation, with an IC50 value of 827.22 µg/mL. The findings demonstrated that the crude EOs and the blend exhibited medicinal activities. However, the EO blend had higher potency.
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creator: Shola Hezekiah Awojide
creator: Abayomi Gideon Adeyemo
creator: Aminat Adebola Adeyemo
creator: Elijah Titilayo Blessing
creator: Adebanjo Jacob Anifowose
creator: Omolara Oladipo-Olalekan
creator: Emmanuel Oluwafemi Adeniyi
creator: Ummuhani Titilayo Abdulazeez
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-11-17
publication date: 2025-11-17
starting page: 9
ending page: 26.
doi: 10.5937/bnsr15-55354

DIGITALIZATION IN THE TOURISM INDUSTRY: IMPACTS ON EMPLOYMENT, JOB SATISFACTION, AND CAREER DEVELOPMENT
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description: Digitalization has significantly transformed the global tourism industry, reshaping workplace structures, job roles, and employee responsibilities. This study examines the impact of digitalization on employees in the Serbian tourism sector, focusing on changes in workplace tasks, challenges and benefits of digital tools, job satisfaction and stress levels, and concerns regarding job security and career development. Using a qualitative research approach, semi-structured interviews were conducted with tourism employees across various sectors, including hotels, travel agencies, airlines, and hospitality services. Findings reveal that while digitalization enhances operational efficiency and reduces administrative burdens, it also introduces new challenges such as increased workload, digital fatigue, and job displacement risks. Automation and AI-driven tools have streamlined processes but reduced personal customer interactions, raising concerns about the loss of human-centered service. Employees expressed mixed feelings about digitalization, with mid-level and senior professionals viewing it as an opportunity for career growth, while entry-level workers feared job redundancy. The study underscores the need for structured digital training, adaptive workforce strategies, and balanced technological integration to support employees during the digital transition. These findings provide valuable insights for businesses and policymakers seeking to optimize digital transformation while ensuring workforce sustainability in the tourism industry.
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creator: Dunja Demirović Bajrami
creator: Marija Bojić
rights: Copyright (c) 2025 Bulletin of Natural Sciences Research
date: 2025-11-28
publication date: 2025-11-28
doi: 10.5937/bnsr16-57764

RADON IN WATER FROM PRIVATE WELLS AND ITS CONTRIBUTION TO INTERNAL EXPOSURE OF POPULATION IN RURAL AREAS AT TOPLICA REGION, SOUTHERN SERBIA
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description: The results presented in this paper are part of the investigating of radon the concentrations from natural sources in the Toplica region. The results refer only to the radon concentrations in water from private captured wells at 12 locations. Radon concentration in water was measured by alpha spectrometry using the RAD 7 – RAD H2O system. The range of radon concentration is from (2.8±1.2) to (76.0±4.0) kBq/m3, and the contribution of radon released from water to the air in the premises was in range (0.8±0.3) to (22.8±1.2) Bq/m3. The annual effective doses of inhaled and ingested radon were determined, the mean values were (114.8±14.8) and (3.2±0.3) μSv/y.
subject: Original Scientific Paper
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creator: Biljana Vučković
creator: Ivana Penjišević
creator: Nataša Todorović
creator: Jovana Nikolov
creator: Dragan Radovanović
creator: Aleksandar Valjarević
rights: Copyright (c) 2024 Bulletin of Natural Sciences Research
date: 2024-07-02
publication date: 2024-07-02
starting page: 60
ending page: 66.
doi: 10.5937/bnsr14-50472

APPLICATION OF COMPRESSIVE SENSING TECHNIQUES FOR ADVANCED IMAGE PROCESSING AND DIGITAL IMAGE TRANSMISSION
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description: The field of compressive sensing (CS) has emerged as a transformative approach in the acquisition and processing of high-dimensional data. This paper presents a comprehensive study on the application of compressive sensing techniques to advanced image processing and digital image transmission. By leveraging the inherent sparsity in natural images, CS allows for significant reductions in the amount of data required for accurate reconstruction, thereby overcoming the limitations imposed by the traditional Shannon-Nyquist sampling theorem. We explore the theoretical foundations of CS, including the principles of sparsity and incoherence, and provide a detailed overview of the Orthogonal Matching Pursuit (OMP) algorithm, a prominent greedy algorithm used for sparse signal recovery. Experimental results demonstrate the efficacy of CS in improving image reconstruction quality, as evidenced by enhancements in peak signal-to-noise ratio (PSNR) and structural similarity index (SSIM). Additionally, we discuss the practical implementation of CS in single-pixel cameras and its potential impact on future imaging technologies. The findings suggest that CS offers a robust framework for efficient image acquisition and processing, making it a valuable tool for various applications in multimedia, medical imaging, and remote sensing.
subject: Original Scientific Paper
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creator: Nenad Stefanović
creator: Boban Sazdić-Jotić
creator: Vladimir Orlić
creator: Vladimir Mladenović
creator: Stefan Ćirković
rights: Copyright (c) 2024 Bulletin of Natural Sciences Research
date: 2024-06-28
publication date: 2024-06-28
starting page: 50
ending page: 59.
doi: 10.5937/bnsr14-51559

RESTRICTED AND EXTENDED THETA OPERATIONS OF SOFT SETS: NEW RESTRICTED AND EXTENDED SOFT SET OPERATIONS
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description: Since its introduction by Molodtsov in 1999, soft set theory has gained widespread recognition as a method for addressing uncertainty-related issues and modeling uncertainty. It has been used to solve several theoretical and practical issues. Since its introduction, the central idea of the theory-soft set operations-has captured the attention of scholars. Numerous limited and expanded businesses have been identified, and their attributes have been scrutinized thus far. We present a detailed analysis of the fundamental algebraic properties of our proposed restricted theta and extended theta operations, which are unique restricted and extended soft set operations. We also investigate these operations’ distributions over various kinds of soft set operations. We demonstrate that, when coupled with other types of soft set operations, the extended theta operation forms numerous significant algebraic structures, such as semirings in the collection of soft sets over the universe, by taking into account the algebraic properties of the extended theta operation and its distribution rules. This theoretical subject is very important from both a theoretical and practical perspective since soft sets' operations form the foundation for numerous applications, including cryptology and decision-making procedures.
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creator: Aslihan Sezgin
creator: Fitnat Nur Aybek
rights: Copyright (c) 2024 Bulletin of Natural Sciences Research
date: 2024-12-24
publication date: 2024-12-24
starting page: 34
ending page: 49.
doi: 10.5937/bnsr14-51091

THE RELATIONSHIP BETWEEN GEODIVERSITY AND BIODIVERSITY – A THEORETICAL APPROACH
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description: The relationship between geodiversity and biodiversity is often considered within geoecological frameworks. Their interaction within real space forms the natural structure of landscapes. Although they are defined as two separate and equivalent systems with different structures, their relationship makes them interdependent, with geospatial distribution being the common point of contact. The term “geodiversity” is relatively recent, defined as the desire to express the opponent of the diversity of the living world – biodiversity. Thus, through a holistic concept, it is possible to observe multiple levels of interaction between geodiversity and biotic resources, revealing their interrelationship. The challenges of researching both geodiversity and biodiversity are characterized by similar shortcomings. Based on the previous researches of different authors, the work aims to define in the best possible way a biotic-abiotic relationship as an essential component in the concept of nature, the sphere of their connection and joint action. However, due to the numerous fields of their interaction, the work only partially defines them, without analyzing each field of interaction, in detail. In addition, the connection of these two concepts also requires interdisciplinary cooperation, the goal of which must be to improve the understanding of biodiversity and geodiversity, and their integration in evaluation, with the common goal of protecting and preserving nature as a whole and its individual parts. To a significant extent, these can be addressed through the application of geoinformatics tools, methods, and techniques, especially Remote Sensing (RS) and Geographic Information Systems (GIS), which offer the possibility of more adequate evaluation and interpretation of results.
subject: Original Scientific Paper
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creator: Marko Ivanović
rights: Copyright (c) 2024 Bulletin of Natural Sciences Research
date: 2024-12-02
publication date: 2024-12-02
starting page: 26
ending page: 33.
doi: 10.5937/bnsr14-54328

THE INHIBITION OF ACNE PROTEASE BY SOME FLAVONES: DFT, SWISSADMET AND MOLECULAR DOCKING
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description: This research sought to find a potent drug for the treatment of acne from six (6) flavones. DFT-B3LYP method was used to determine the molecular descriptors like HOMO, LUMO, Dipole moment, and volume of the ligands and standard drugs. SWISSADMET was employed to ascertain the pharmacokinetic properties of the ligands, and molecular docking was achieved by using PyRx and discovery studiosoft wares. It was observed that the six flavones showed better inhibition against acne main protease than the standard drugs, and from the binding affinity results, 5-hydroxy-2-phenylchromen-4-one best inhibited acne protease. The choice of flavones was based on the fact that they have good antibacterial properties because acne thrives in the presence of bacteria.
subject: Original Scientific Paper
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creator: Dayo Latona
creator: Abiodun Taiwo
creator: Yemisi Asibor
creator: Funke Olarinoye
creator: Banjo Semire
rights: Copyright (c) 2024 Bulletin of Natural Sciences Research
date: 2024-12-02
publication date: 2024-12-02
starting page: 11
ending page: 19.
doi: 10.5937/bnsr14-51980

ANALYSIS OF THE SELF-SUFFICIENCY OF WHEAT PRODUCTION IN BOSNIA AND HERZEGOVINA
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description: Wheat is recognized as a crucial staple food across nearly all countries. Achieving a specific level of self-sufficiency in primary food products is a common objective for nations, aimed at safeguarding domestic production, minimizing dependency on imports, and mitigating disruptions in global and regional supply chains. This study provides an analysis of wheat production and yields in Bosnia and Herzegovina, with the goal of evaluating the self-sufficiency of wheat production. The analysis covers the period from 2010 to 2019. The study places particular emphasis on spatial analysis, including production, yield, and self-sufficiency at the level of local administrative units. The findings indicate that Bosnia and Herzegovina's self-sufficiency in wheat production stands at 54%, with significant variability in production quantities across different local government units. These insights offer a foundation for future research that could delve deeper into the spatial-temporal, economic, and food security dimensions of wheat production.
subject: Original Scientific Paper
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creator: Marko Ivanišević
creator: Tatjana Popov
creator: Dijana Gvozden Sliško
rights: Copyright (c) 2024 Bulletin of Natural Sciences Research
date: 2024-11-17
publication date: 2024-11-17
starting page: 20
ending page: 25.
doi: 10.5937/bnsr14-53257

EVALUATING THE INFLUENCE OF TRYPANOSOMIASIS ON MURINE MODEL USING Corchorus olitorius LEAF EXTRACT AS A TRYPANOCIDAL AGENT
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description: Trypanosomiasis, a parasitic disease caused by trypanosomes, which are flagellate protozoa transmitted through the bite of the tsetse fly, manifests with symptoms including substantial weight loss, anemia, fever, edema, adenitis, dermatitis, and nervous disorders. This research investigated the impact of trypanosomiasis on a murine model while utilizing Corchorus olitorius leaf extract as a potential trypanocidal agent. An acute toxicity analysis was conducted following Lorke’s method, and the antitrypanosomal efficacy was assessed in rats at doses of 100, 200, and 400 mg/kg over three weeks, monitoring changes in parasitemia count, body weight, and hematological parameters. Additionally, lipid profile, electrolyte concentration, and liver and kidney function were evaluated using standard techniques. The extract demonstrated potent antitrypanosomal activity at 400 mg/kg, significantly reducing the parasitemia count to 11.33±4.16 count/mL compared to the positive control at 2.5 mg/kg body weight doses. Furthermore, the 400 mg/kg dose notably increased packed cell volume and body weight in infected rats. Moreover, there were no significant discrepancies in numerous hematological parameters between the infected treated with diminazene aceturate and the extract's 400 mg/kg body weight. This study suggests that Corchorus olitorius extract exhibits significant antitrypanosomal, antilipidemic, and erythropoietic effects, mitigating parasitemia count, lipid levels, and oxidative damage by impeding the biochemical activities of trypanosomes through its active constituents. Thus, Corchorus olitorius extract may offer an alternative therapeutic approach for managing trypanosomal infections.
subject: Original Scientific Paper
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creator: Fatima M. Madaki
creator: Adamu Y. Kabiru
creator: Ogunrombi D. Clinton
creator: Sakariyau A. Waheed
creator: Yunusa O. Ibrahim
rights: Copyright (c) 2024 Bulletin of Natural Sciences Research
date: 2024-11-11
publication date: 2024-11-11
starting page: 1
ending page: 10.
doi: 10.5937/bnsr14-51999

ASSESSMENT OF HEAVY METALS IN FISH AND SEDIMENTS FROM RIVER MTAKUJA IN THE VICINITY OF A GOLD MINE IN TANZANIA
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description: Concentrations of heavy metals namely Cr, Fe, Cu, Zn, As, Cd and Pb in African Sharptooth Catfish (clarias gariepinus) and sediment from river Mtakuja Tanzania were analyzed using the Energy Dispersive X-ray Fluorescence spectrometry technique. 32 samples from fish and sediment were investigated. The results show that the concentration of heavy metals was higher in upstream areas than in the downstream area. The concentration of Fe of 428.5 mg/kg in catfish from the upstream area was about 2 times 243.8 mg/kg obtained from the same fish in the downstream area. Similar cases observed for sediments with Fe concentration of 127626.9 mg/kg from upstream that was about 6 times higher than that of 21460.3 mg/kg from downstream area. The concentration of 44.8 mg/kg for Cu in the upstream area sediment was also about 2 times higher than 23.2 mg/kg in the downstream area sediment, while for as the concentration of 13.2 mg/kg was measured in the upstream, which is which is more than 5 times 2.5 mg/kg measured in downstream. The concentration of Cr in the catfish was 17.6 mg/kg which is higher than the permissible limit values of 0.8 mg/kg set by the European Commission (EC), 0.2 mg/kg set by the Food and Agricultural Organization (FAO) and 0.15 mg/kg the World Health Organization (WHO) limit. Moreover, the concentration of Cd was 3.0 mg/kg, which is above the permissible level of 0.2 mg/kg recommended by the EC and WHO. A positive correlation exists between the Cu, Pb, Fe and Cd concentration found in sediments and fish samples. The results show that the river Mtakuja is polluted by mining waste, domestic and agrochemical activities. This suggest that, there is a need for regular monitoring of heavy metal in river Mtakuja in order to monitor and protect aquatic organisms and health of benefactors of this river.
subject: Original Scientific Paper
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creator: Victor A. Panga
creator: Mwingereza J. Kumwenda
creator: Ismael N. Makundi
rights: Copyright (c) 2023 Bulletin of Natural Sciences Research
date: 2023-12-29
publication date: 2023-12-29
starting page: 10
ending page: 18.
doi: 10.5937/bnsr13-44479

ON THE SECOND ORDER STATISTICS OF THE RATIO OF TWO FISHER-SNEDECOR RANDOM VARIABLES AND ITS APPLICATION TO INTERFERENCE LIMITED COMMUNICATIONS
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description: The paper investigates the higher order statistics of the ratio of two Fisher-Snedecor F (FS-F) random variables (RVs) and its application to wireless communications in the presence of co-channel interference. Namely, the work provides novel expressions for probability density function (PDF), cumulative density function (CDF), level crossing rate (LCR) and average fade duration (AFD) of the ratio of two FS-F RVs. Numerical examples of the analytically derived statistical measures in terms of FS-F multi-path and shadowing parameters are shown and examined. Moreover, the impact of the number of interferes on the considered measures are further presented and examined.
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creator: Časlav Stefanović
creator: Danijel Đošić
creator: Stefan Panić
rights: Copyright (c) 2023 Bulletin of Natural Sciences Research
date: 2023-12-28
publication date: 2023-12-28
starting page: 30
ending page: 34.
doi: 10.5937/bnsr13-44582

OPTIMIZATION OF THE 2P FIFTH DEGREE CONVOLUTION KERNEL IN THE SPECTRAL DOMAIN
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description: The first part of the paper describes a two-parameter (2P) fifth-order interpolation kernel, r. After that, from the 2P kernel, the kernel components were created. By applying the Fourier transformation to each kernel component, the spectral components of the 2P kernel were obtained. The spectral characteristic of the 2P kernel, H, was created from the spectral components. After that, the algorithm, that optimizes the parameters of the 2P kernel so as to eliminate the ripple of the spectral characteristics, is described. The optimization was performed in such a way that the spectral characteristic developed in the Taylor series, HT. With the condition for the elimination of the members of the Tylor series, which greatly affect the ripple of the spectral characteristic, the optimal kernel parameters (αopt, βopt) were determined. The second part of the paper describes an Experiment, in which the interpolation accuracy of the 2P kernel was tested. Convolution interpolation, with the 2P kernel, was performed over the signals from the Test base. The Test base is created with musical signals. By analyzing the interpolation error, which is represented by the Mean Square Error, MSE, the precision of the interpolation was determined. The results (αopt, βopt, MSEmin) are presented on tables and graphs. Detailed comparative analysis showed higher interpolation precision with the proposed 2P interpolation kernel, compared to the interpolation precision with, 1P interpolation kernel. Finally, the numerical values of the optimal kernel parameters, which are determined by the optimization algorithm proposed in this paper, were experimentally verified.
subject: Original Scientific Paper
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creator: Nataša Savić
creator: Zoran Milivojević
creator: Bojan Prlinčević
rights: Copyright (c) 2023 Bulletin of Natural Sciences Research
date: 2023-12-28
publication date: 2023-12-28
starting page: 19
ending page: 29.
doi: 10.5937/bnsr13-41946

DETERMINATION OF POLYPHENOL AND FLAVONOID CONTENT AND ANTIOXIDANT ACTIVITY OF ETHANOLIC, CHLOROFORM AND ETHYL ACETATE EXTRACT OF THE PLANT SPECIES Thymus serpyllum L.
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description: This research aimed to examine the phytochemical composition, content of polyphenols and flavonoids, and antioxidant capacity of ethanolic, ethyl acetate, and chloroform extract of the plant species Thymus serpyllum L. The extracts were tested for the presence of alkaloids, tannins, saponins, phenolic compounds, flavonoids, steroids, terpenoids, cardiotonic glycosides, and coumarins. The total content of polyphenols was determined spectrophotometrically with the Folin-Ciocalteu reagent, according to Singleton's method, while the total content of flavonoids was determined using the method with aluminum chloride. The highest contents of polyphenols and flavonoids were determined in ethanolic extracts, where the measured values ranged from 111.00 ± 0.26 to 288.00 ± 0.23 mg GAE/g of dry extract for polyphenols, and 65.80 ± 0.19 to 198.22 ± 0.34 mg RE/g dry extract for flavonoids. The antioxidant activity was determined by the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The tested extracts show a good effect on DPPH radical inhibition, with the IC50 values ranging from 35.15 ± 0.33 to 398.27 ± 0.24 μg/ml, and the greatest ability of ethanolic extract to neutralize the DPPH radical. Qualitative phytochemical analysis of the extracts showed a wide spectrum of phytochemicals, where ethanol, as the most polar solvent, extracts almost all tested phytochemicals.
subject: Original Scientific Paper
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creator: Marija Aksić
creator: Biljana Dekić
creator: Suzana Janićević
rights: Copyright (c) 2023 Bulletin of Natural Sciences Research
date: 2023-06-23
publication date: 2023-06-23
starting page: 5
ending page: 9.
doi: 10.5937/bnsr13-44767

RECORDS OF LICHEN SPECIES FROM GENUS ACAROSPORA, NEW FOR SERBIA, SOUTHWEST BALKAN PENINSULA
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description: The lichens: Acarospora impressula, A. nitrophila, A. nodulosa, A. schleicheri, A. sinopica, A. smaragdula and A. umbillicata, collected in North Kosovo are reported as a new species to Serbia, following a recent lichenological survey. Location, herbarium deposits and substrates are given, together with notes on distribution of the reported taxa.
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creator: Gordana Aleksić
creator: Predrag Vasić
creator: Tatjana Jakšić
rights: Copyright (c) 2023 Bulletin of Natural Sciences Research
date: 2023-06-09
publication date: 2023-06-09
starting page: 1
ending page: 4.
doi: 10.5937/bnsr13-42787

NOMA COOPERATIVE RELAYING SYSTEMS OVER RICIAN-SHADOWED FADING CHANNELS
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description: Non-orthogonal multiple Access (NOMA) is an efficient 5G technology that enables network spectral efficiency increase and network access latency. In order to additionally improve the reliability of transmission and increase the achievable rate of NOMA system, combined utilization of NOMA and cooperative relay transmission (CRS) could appear as effective remedy. In this work, we will carry out performance analysis of NOMA based CRS over Rician-Shadowed fading channels. The closed-form expression for the exact average achievable rate is presented in the form of Meijer G functions infinite-series. Numerical results are presented in order to manifest the credibility of the presented method.
subject: Original Scientific Paper
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creator: Stefan R. Panić
creator: Sergei Khotnenok
rights: Copyright (c) 2022 Bulletin of Natural Sciences Research
date: 2022-10-06
publication date: 2022-10-06
starting page: 31
ending page: 35.
doi: 10.5937/bnsr12-40124

NEW PROOF OF AHLFORS LEMMA ABOUT GREEN STOKES FORMULA FOR DISTRIBUTIONS
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description: The paper presents a new proof of Ahlfors lemma about Green Stokes formula for distributions. The proof is performed directly using test functions instead of using convolutions.
subject: Original Scientific Paper
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creator: Ana Savić
rights: Copyright (c) 2022 Bulletin of Natural Sciences Research
date: 2022-12-30
publication date: 2022-12-30
starting page: 25
ending page: 30.
doi: 10.5937/bnsr12-39725