Karamanoğlu Mehmetbey University
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Influence of core window height on thermal characteristics of dry-type transformers
No full textElevated temperatures in transformer windings and cores pose a significant risk of damage to power transformers. The objective of this work is to analyze the influence of core window dimensions on the thermal efficiency of power transformers. Analytical approaches are limited in their ability to consider the impact of core window dimensions on the transformer's thermal behavior. Conversely, experimental methods are both expensive and time-consuming. To overcome these constraints, this work assesses and optimizes the temperature distribution in dry-type power transformers using finite element models, specifically examining the impact of the core window. The thermal model treats core and winding losses as sources of heat generation. Four different transformers, with varying heights of the transformer core window, have been modeled to assess the impact of window height on the thermal conditions of the transformers. The simulation findings indicate that variations in core window height have a significant impact on the transformer's thermal properties. By comparing the model's predictions of short-circuit impedance with experimental data, this study demonstrates the model's capability to reliably estimate parameters influenced by core window variations, thereby validating its usefulness. © 2025 The Author(s
Search for nuclear modifications of (formula presented) meson production in (formula presented)-pb collisions at (formula presented)
No full textNuclear medium effects on (Formula presented) meson production are studied using the binary-collision scaled cross section ratio between events of different charged-particle multiplicities from proton-lead collisions. Data, collected by the CMS experiment in 2016 at a nucleon-nucleon center-of-mass energy of (Formula presented), corresponding to an integrated luminosity of (Formula presented), were used. The scaling factors in the ratio are determined using a novel approach based on the (Formula presented) cross sections measured in the same events. The scaled ratio for (Formula presented) is consistent with unity for all event multiplicities, putting stringent constraints on nuclear modification for heavy flavor. © 2025 CERN, for the CMS Collaboration
Novel hyperchaotic system: Implementation to audio encryption
No full textTo overcome the limitations of existing low-dimensional chaotic systems, particularly their vulnerability to degradation, this study introduces a novel family of discrete hyper-chaotic systems, designed using a one-dimensional quadratic map. The dynamic behavior of the systems is analysed using Lyapunov exponents and sample entropy to evaluate their complexity and robustness. The results demonstrate that the proposed systems exhibit higher ergodicity, greater Lyapunov exponents and better randomness compared to existing chaotic systems. Exploiting these systems, a novel fractal K-means audio encryption (FKM-AE) algorithm is proposed, integrating fractal algorithms with the K-means grouping approach. Simulations reveal that the proposed method effectively reduces the correlation of audio messages across adjacent time intervals and robustly resists various attacks, demonstrating its high performance. © 2025 Elsevier Lt
A half-natural origin approach for anticancer and antioxidant activities using sporopollenin and pillar[5]arene macroring
No full textSporopollenin is a natural biomacromolecule which can be found in the outer wall (exine) of spores or pollens that it can be performed with clever designing in a lot of innovative and scientific areas. In this paper, a novel sporopollenin reformed with a recently synthesized pillar[5]arene molecule were elucidated by FT-IR spectroscopy, TGA and SEM techniques. This study is the first report leading to a comprehensive investigation of the biological applications of a functionalized bio-microcapsule including antioxidant and anticancer properties. Two in vitro assays (DPPH and FRAP) were used to determine the antioxidant activities of sporopollenin and functionalized microcapsules. Furthermore, the anticancer activities of these microcapsules were tested on 2 different cancer cell lines (HT-29 and MCF-7), and a fibroblast cell line (L929) by the Alamar blue assay. Among the samples tested in the antioxidant capacity results, especially Sp-P[5] exhibited higher antioxidant capacity and stood out with IC50: 101.98 f 4.32 mu g/mL in DPPH assay and IC50: 87.97 f 3.14 mu g/mL in FRAP assay. Similar to the antioxidant result, Sp-P[5] bio-microcapsule had greater cell inhibition on HT-29 (IC50: 132.31 f 5.38 mu g/mL), MCF-7 (IC50: 107.30 f 8.28 mu g/mL), and L929 (IC50: 255.80 f 4.91 mu g/mL) cell lines than Sp and Sp-APTMS. The analysis results in the study show promise for the development of sporopollenin-based micro- capsules to deliver and enhance the biological activity of compounds with therapeutic potential
Fabrication and optical characterization of V-shaped micro/nano-grooves on indium phosphide surface through double cell electrochemical etching
Get PDFA versatile and simple method of fabricating micro and nano-grooves on the indium phosphide (InP) semiconductor surface using a double-cell electrochemical etching process is presented in this work. The formation mechanism of the groove structures is thoroughly investigated as a function of different etching parameters, including varying acid concentration, current density, and etching time. The surface morphologies and chemical compositions of the grooves are analyzed using a scanning electron microscope (SEM) equipped with an energy dispersive X-ray spectrometer (EDS). It has been observed that electrochemical etching using HCl-based etchants leads to the spontaneous formation of micro and nano-sized grooves on certain side facets of patterned structures, depending on the etching parameters. At high acid concentration, micro-grooves with a lateral length of 980 nm are formed by applying a low current density of 30 mA/cm2 for 6 min. On the other hand, it is revealed that the applied current density needs to be increased to 50 mA/cm2 to obtain a regular grooved InP surface at low acid concentration. Tailoring the etching parameters results in much smaller structures with novel nano-sized features. The impact of morphology on the optical and carrier recombination properties is comprehensively investigated using a steady state photoluminescence (PL) spectrometer and a time-resolved fluorescence lifetime imaging microscope (FLIM). At room temperature, the nano-grooved InP surface exhibits a well-defined, strong emission peak at 920 nm and a carrier recombination lifetime of 6.06 ns. Patterning semiconductor micro/nanostructures with precisely controlled geometries offers a promising opportunity to enhance the performance of optoelectronic devices
Highly efficient photocatalyst based on Zn2-xBaxSnO4 alloying nanoparticles with enhanced photocatalytic activity
No full textIn this study, an effective Zn2-xBaxSnO4 alloying nanoparticles were hydrothermally designed with a series of barium cation as alloying dopant and utilized as a photocatalyst to decompose the rhodamine B which causes harmful effects on humans such as allergic dermatitis, skin irritation, mutation, and cancer. It is noteworthy that the Zn1.988Ba0.012SnO4 alloying-based catalyst exhibited more than 99 % degradation in only 140 min in wastewater than barium-free ternary oxide. Moreover, the reaction rate of Zn1.988Ba0.012SnO4 alloying-based catalyst was enhanced to 0.032 min-1 compared with barium-free ternary oxide (0.0179 min-1). Based on scavenger trapping experiments, hydroxyl radicals are the main reactive oxygen species responsible for photocatalytic activity of Zn1.988Ba0.012SnO4 alloying-based catalyst. Besides, the photocatalytic rate was maintained 94.89 % after 5th cycle. This research not only provides a novel strategy for developing alloying-based catalysts but also unveils their potential in photoelectrochemistry and photocatalysis
İndustry 4.0 and management 4.0: examining the ımpact of environmental, cultural, and technological changes
No full textEnvironmental, cultural, and technological developments, along with Industry 4.0 technologies—one of the most significant topics of recent years—have led to a paradigm shift in management functions and practices. These changes raise questions about the necessity of discussing the emergence of a new revolution in management, referred to as Management 4.0. Accordingly, the purpose of this exploratory sequential mixed-methods study is to examine the impact of environmental, cultural, and technological developments on management functions through Industry 4.0 technologies and to explore the underlying elements of the qualitative findings in depth. To address the research problem, 401 business managers participated in the quantitative phase of the study, while 10 business managers took part in the qualitative phase. The quantitative phase also included scale development. The study discusses the prediction of Management 4.0 and evaluates its feasibility. The findings from the quantitative research indicate that Industry 4.0 technologies play a mediating role between environmental changes and management functions. Meanwhile, the qualitative findings suggest that environmental, cultural, and technological developments are shaping a new cultural environment, necessitating adaptation to a new order. As a result of these changes, employees are expected to take part in decision-making processes. In terms of management functions, key developments include enhanced planning and coordination, the rise of platform-based business models, increased collaboration with competitors, the adoption of a modern management approach, and more frequent monitoring and control. Furthermore, the study reveals that although business managers in Turkey recognize the necessity of adopting Industry 4.0 technologies, their widespread implementation remains limited. This study contributes to the literature by introducing the concept of Management 4.0 and developing the Management 4.0 Foresight Scale. © 2025 by the authors
Measurement of Multidifferential Cross Sections for Dijet Production in Proton-Proton Collisions at √ s = 13 Te V
Get PDFA measurement of the dijet production cross section is reported based on proton-proton collision data collected in 2016 at √s=13TeV by the CMS experiment at the CERN LHC,corresponding to an integrated luminosity of up to 36.3 fb−1 . Jets are reconstructed with the anti- kT algorithm for distance parameters of R=0.4 and 0.8. Cross sections are measured double-differentially (2D) as a function of the largest absolute rapidity |y|max of the two jets with the highest transverse momenta pT and their invariant mass m1,2 , and triple-differentially (3D) as a function of the rapidity separation y∗ , the total boost yb , and either m1,2 or the average pT
of the two jets. The cross sections are unfolded to correct for detector effects and are compared with fixed-order calculations derived at next-to-next-to-leading order in perturbative quantum chromodynamics. The impact of the measurements on the parton distribution functions and the strong coupling constant at the mass of the
Z boson is investigated, yielding a value of αS(mZ)=0.1179±0.001
Examination of heavy metal concentrations and their interaction with anthropogenic sources in Ermenek Dam Lake (Turquoise Lake)
No full textThis study aims to determine the spatial distribution of heavy metal pollution in Ermenek Dam Lake, water quality assessment and pollution sources. For this purpose, samples were taken 6 times a year from 12 points determined in 2024. Physico-chemical parameters and heavy metals were analyzed in the study. Using the analysis results, indexes such as Water Quality Index and Heavy Metal Pollution Index were calculated. The results show that the lake water complies with TS 266 and WHO standards. The index results indicate that the lake water is at low pollution and risk level and is safe. The distribution and sources of heavy metals were examined using correlation analysis, Principal Component Analysis and Hierarchical Cluster Analysis. Correlation analyses showed that there were significant relationships between pH, temperature, conductivity, dissolved oxygen and TDS and heavy metals. PCA results revealed that Zn was positively correlated with temperature and pH, while Mn and Ni were inversely correlated. The alignment of Pb, Cu and Cd in the same direction showed that these parameters were affected by common sources. HCA results showed that Cr and Fe have similar transport and source properties, while Mn and Ni are affected by different sources. In general, it was determined that heavy metal pollution in lake water was at low levels and local concentrations were present. The study revealed the effects of anthropogenic activities on the lake ecosystem. The findings of the study provide a guiding basis for water quality management in similar hydrological systems
A parallel color image encryption algorithm based on a 2d logistic-rulkov neuron map
No full textImages are widely used in social networks, necessitating efficient and secure transmission, especially in bandwidth-constrained environments. This paper aims to develop a color image encryption algorithm that enhances security while optimizing computational efficiency. A novel parallel color image encryption algorithm based on the 2D Logistic-Rulkov neuron map (2D-LRNM) is proposed. In this approach, the three channels of the color image are first separated. Cross-channel information interaction is introduced to form three new channels, which are then processed in parallel. During the encryption process of each channel, a block-wise parallel encryption mechanism is applied, ensuring simultaneous encryption of each block. This block-wise strategy effectively leverages parallel computing resources and balances the task load. To meet the demand for a large number of keystreams during encryption, the 2D-LRNM is introduced. It combines the simplicity and chaotic properties of the Logistic map with the multi-timescale dynamics and neurodynamic behaviors of the Rulkov map. By overcoming the dimensional limitations inherent in the single Logistic map, this approach extends the system to a two-dimensional framework, significantly increasing the complexity of chaotic behavior and improving its unpredictability. Experimental results demonstrate that the proposed encryption algorithm achieves high security and reduces computation time by approximately 83.3%. © 2014 IEEE