Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(110)
- Güler, Ömer(70)
- Akkurt, Nevzat(69)
- Serdar, Osman(57)
- Yucesan, Melih(55)
- Celik, Erkan(53)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Bulut, Hasan(49)
- Baskonus, Haci Mehmet(48)
- Paksoy, Mehmet Yavuz(46)
- Yildirim, Numan(45)
- Kocabaş, Mehmet(41)
- Yildirim, Nuran Cikcikoglu(41)
- Zengin, Gokhan(40)
- Alataş, Mevlüt(39)
- Ince, Muharrem(38)
- Benzer, Fulya(37)
- Mete, Suleyman(34)
- Aslan, Naim(33)
- Kutlu, Banu(33)
- Yildirim, Ozal(33)
- Topal, Murat(32)
- Tanyol, Mehtap(30)
- Batan, Nevzat(28)
- Özkul, İskender(28)
- Kök, Mediha(27)
- Utku, Anıl(27)
- Can, Erkan(26)
- Danabas, Durali(26)
- Sulaiman, Tukur Abdulkadir(26)
- Ates, Mehmet(25)
- Ezer, Tülay(25)
- Guler, Omer(25)
- Kutluyer, Filiz(25)
- Say, Yakup(25)
- Serin, Faruk(25)
- Erguven, Gokhan Onder(24)
- Onat, Onur(24)
- Cakilcioglu, Ugur(23)
Yayınlar
- MakaleYalnız künye2026Scopus SJRQ1Computational fluid dynamics analysis of battery pack with cooling channel integrated with innovative thermoelectric cooling stations
Yardımcı, Uğurcan; Tuğan, Volkan
In this study, a novel liquid cooled battery thermal management system integrated with a thermoelectric assisted cooling channel has been designed. To prevent battery cells from operating at high temperatures and to ensure a uniform temperature distribution among the cells, multiple thermoelectric stations were placed at various positions along the cooling channel. The performance of four different models created with various temperature combinations, as well as a conventional model without thermoelectrics, was investigated through Computational Fluid Dynamics simulations. In the analyses, five different thermoelectric temperatures (293.15–298.15 K), two different mass flow rates (0.0013 and 0.0018 kg/s), and two different initial temperatures (298.15 and 303.15 K) were examined. The results demonstrated a significant improvement in the performance of the battery thermal management system with the use of the thermoelectric assisted cooling channel. It was determined that lowering the initial temperature from 303.15 K to 298.15 K and increasing the mass flow rate from 0.0013 kg/s to 0.0018 kg/s resulted in better cooling performance and more uniform distribution for the thermoelectric assisted system. Under the conditions of a 0.0013 kg/s mass flow rate and an initial temperature of 303.15 K, the highest reduction in maximum battery temperature, compared to the non-thermoelectric design, was achieved in Model B with 9.207 K. Under the same conditions, the most significant reduction in maximum temperature difference was observed in Model D with 4.758 K. Furthermore, the Root Mean Square Spread analysis results revealed that Model B provided the best performance in terms of temperature distribution.
AtıfScopus7WoS7OpenAlex10
İncele - MakaleAçık Erişim2026Scopus SJRQ1Structural and radiation shielding properties of high-entropy rare-earth oxide-doped borosilicate glass
Güler, Ömer; Yılmaz, Demet; Kanca, Muhammed Sait; Kök, Mediha; Taşgın, Yahya
In this study, the incorporation of a high-entropy rare-earth oxide, (GdLaEuPrDyY)2O3 (RE-HEO), into a borosilicate glass matrix was investigated with the aim of improving radiation shielding performance while preserving the structural integrity of the glass. The RE-HEO was first synthesized by high-energy mechanical alloying and then introduced into the glass system at concentrations ranging from 0 to 8 wt% using a conventional melt-quenching process. The structural and microstructural properties of the prepared samples were examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy combined with energy-dispersive spectroscopy (SEM–EDS). The analyses confirmed that the amorphous nature of the borosilicate glass was maintained and that the rare-earth elements were homogeneously distributed within the matrix. The radiation shielding performance was evaluated experimentally using Am-241, Ba-133, and Ra-226 gamma sources, and supported by theoretical calculations of key parameters including mass attenuation coefficient (MAC), half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), exposure buildup factor (EBF), and fast neutron removal cross-section (ΣR). The results showed that increasing RE-HEO content leads to a noticeable improvement in gamma-ray attenuation. In particular, the sample containing 8 wt% RE-HEO exhibited a MAC value of 0.131 cm2/g and an HVL of 2.03 cm at 356 keV, indicating shielding performance comparable to that of conventional lead-containing glasses. In addition, irradiation tests performed using a Co-60 gamma source revealed that the amorphous structure remains stable after exposure. Overall, the findings suggest that RE-HEO-doped borosilicate glass can be considered a promising lead-free alternative for radiation shielding applications.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ2Radiation shielding performance of CeO2-reinforced ternary nanocomposites based on biodegradable polymers and waste-derived polystyrene
Pekdemir, Mustafa Ersin; Yilmaz, Demet; Selçuk Pekdemir, Sibel; Gülhan, Aleyna; Yalçin Kuzu, Serpil; Altun, Sedanur; Taşgin, Yahya
The development of sustainable polymer-based materials for radiation shielding has attracted increasing interest, particularly for lightweight and flexible applications. In this study, ternary nanocomposites based on poly (hydroxyalkanoate) (PHA), poly (ε-caprolactone) (PCL), and polystyrene (PS) were prepared and reinforced with cerium oxide (CeO2) nanoparticles (5–15 wt%) to enhance radiation shielding performance. Structural characterization confirmed the preservation of polymer chemical structures and the successful incorporation of crystalline CeO2, while SEM observations revealed a relatively homogeneous nanoparticle dispersion within the ternary matrix, particularly at intermediate filler loadings. Thermal analysis demonstrated enhanced thermal stability with increasing CeO2 content, as evidenced by an increase in residual mass from 0.42% for the neat blend to 11.21% for the nanocomposite containing 15 wt% CeO2, along with a shift of degradation onset temperatures toward higher values. Photon shielding performance was experimentally evaluated in the energy range of 13.37–59.54 keV. The incorporation of 15 wt% CeO2 increased the mass attenuation coefficient (MAC) from 1.277 to 12.366 cm2 g−1 at 13.37 keV, corresponding to an approximately ninefold enhancement, while significantly reducing the half-value layer (HVL) and mean free path (MFP). Neutron shielding analysis showed a slight decrease in thermal neutron attenuation due to hydrogen dilution within the polymer matrix, whereas fast neutron attenuation and neutron removal cross sections exhibited only minor variations; the fast neutron removal cross section increased modestly from 0.1014 to 0.1047 cm−1 with 15 wt% CeO2 addition. Overall, the results highlight clear structure–property–performance relationships in CeO2-reinforced PHA/PCL/PS nanocomposites, demonstrating their potential as lightweight radiation shielding materials for low energy protection with improved thermal stability and shielding efficiency.
AtıfScopus2OpenAlex1
İncele - MakaleYalnız künye2026Scopus SJRQ2Comprehensive Characterization of Nano-Eu2O3 Reinforced Borotellurite Glasses: Synthesis, Physical, Structural, and Gamma and Neutron Attenuation Properties
Durmus, Hasan; Kilic, Gökhan; Ilik, E.; Kavaz, Erkan; Güler, Ömer; Birdoğan, Selcuk; Almisned, Ghada; Tekin, Hüseyin Ozan
This study presents a systematic investigation of lithium borotellurite glasses reinforced with nano-Eu2O3, with the aim to enhance the structural stability and radiation shielding performance. Glasses were synthesized with Eu2O3 concentrations from 0 to 10 mol % and characterized through density, X-ray diffraction, and transmission electron microscopy. The results showed that the density increased steadily from 4.030 to 4.734 g/cm3 with the Eu addition, while the molar volume also expanded, indicating that the incorporation of larger Eu3+ ions induced network expansion alongside densification. The X-ray diffraction patterns showed amorphous structures for all the compositions except Eu(n)2, which exhibited local crystallinity, later suppressed at higher Eu levels. The transmission electron microscopy pictures and energy dispersive spectroscopy mapping showed homogeneous nanoparticle distribution without clustering. Gamma-ray attenuation studies demonstrated clear improvements with Eu doping: the linear attenuation coefficient increased from 8.33 cm−1 (Eu(n)0) to 12.42 cm−1 (Eu(n)10) at 81 keV, while the half-value layer values decreased, confirming superior low-energy absorption. Experimental neutron studies revealed ΣR values comparable to standard neutron moderators, with Eu(n)10 showing a favorable balance of gamma and neutron shielding. Limitations include the restricted photon energy window and single neutron source. Future work should extend testing to higher energies, thermal/epithermal neutron ranges, and mechanical and durability assessments. Overall, nano-Eu2O3 reinforcement provides a promising pathway toward multifunctional transparent shielding glasses.
- MakaleAçık Erişim2026Scopus SJRQ1Investigation of the structural, thermal and radiation shielding properties of (Er0.2Yb0.2Sm0.2La0.2Eu0.2)2Zr2O7 high entropy oxide reinforced tin matrix composite
Güler, Ömer; Yılmaz, Demet; Kanca, M. Sait; Kök, Mediha; Güler, Seval Hale; Taşgın, Yahya
This study investigates the structural, thermal, and radiation shielding properties of (Er0.2Yb0.2Sm0.2La0.2Eu0.2)2Zr2O7 high entropy oxide (HEO) reinforced tin (Sn) matrix composites. In the first stage of the study, HEO powders were synthesized by grinding at 350 rpm for 30 h using a solid-state method with mechanical alloying assistance, and then calcining at 1100 °C for 8 h. In the second stage, composites were produced by mixing HEO-reinforced Sn matrix materials containing 1%, 5%, and 10% reinforcement, pelleting them under 200 MPa pressure, and then sintering them at 300 °C for 3 h. In the first stage of the study, (Er0.2Yb0.2Sm0.2La0.2Eu0.2)2Zr2O7 HEO powders were synthesized using a mechanical alloying-assisted solid-state route. In the second stage, HEO-reinforced Sn matrix composites containing 1 wt%, 5 wt%, and 10 wt% reinforcement were produced. The phase formation and crystallographic structure of the synthesized powders and composites were characterized using X-ray diffraction. Thermal behavior and phase stability were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The thermal analysis results revealed dehydration and structural stabilization processes at intermediate temperatures, while crystallization of the HEO phase was observed at elevated temperatures. In addition, oxidation behavior of the Sn matrix composites was evaluated, showing that the presence of HEO particles significantly suppresses mass gain during high-temperature oxidation, indicating improved thermal stability. Finally, the radiation shielding performance of the samples was experimentally evaluated within the photon energy range of 59.54–609.2 keV using Am-241, Ba-133, and Ra-226 radioactive sources together with a Ultra-Low Energy Germanium (ULEGe) detector. The results demonstrate that the incorporation of HEO particles leads to minor, energy-dependent variations in the radiation attenuation capability of the tin matrix, influenced by the presence of high atomic number rare-earth elements and modified microstructural characteristics. The gamma radiation protection coefficient (RPC) values indicate strong attenuation in the low photon energy region, decreasing to approximately 16–19% at 609.3 keV. Moreover, the measured neutron equivalent dose rates increase from 0.054 µSv/h for pure Sn to 0.285 µSv/h for the Sn–10%HEO composite, indicating that HEO incorporation modifies the neutron interaction behavior of the Sn matrix composites.
- MakaleAçık Erişim2026Scopus SJRQ2Data-Driven Prediction of Climate Variables in Agricultural Cities of India With Hybrid GA-TCN-LSTM Model
Utku, Anil
Accurate prediction of climate variables is important in reducing the effects of natural disasters and taking preventive measures for agriculture and food security, energy sector, public health, and water resources management. For agricultural production, it is essential for producers to determine strategies for their agricultural activities and to increase agricultural productivity. Issues such as determining planting and harvest times, determining pesticides to be used against agricultural pests, selecting products to be planted, irrigation, and sustainable agriculture are directly related to climate variables. In this study, a GA-TCN-LSTM hybrid prediction model was created to determine climate variables such as relative humidity, temperature, wind speed, and dew point in Bhopal, Indore, Kanpur, Ludhiana, and Patna, which are among the prominent cities of India in terms of agricultural production. The hyper-parameters of the developed model using the temporal convolutional networks (TCN) and long short-term memory (LSTM) were optimized with the genetic algorithm (GA), and the GA-TCN-LSTM hybrid model was created. GA-TCN-LSTM was extensively compared with the base TCN-LSTM, convolutional neural network (CNN), LSTM, TCN, and CNN-LSTM. The compared models were tested using approximately 15 years of hourly, up-to-date, and real-time data of the cities. Experiments showed that GA-TCN-LSTM outperformed the compared models and had above 0.9 R-Squared (R2) for the majority of cities and climate variables.
AtıfScopus2WoS1OpenAlex2İncele - MakaleAçık Erişim2026Scopus SJRQ2Production and Thermal–Structural Characterization of Nano-Oxide-Doped Paraffin-Based Phase Change Composite Materials for Thermal Storage Applications
Yücel, Halit Lutfi; Özdemir, Osman; Kahraman, Gökhan
Paraffin-based composite phase change materials (PCMs) have been synthesized for thermal energy storage applications to enhance thermal conductivity and stability while maintaining latent heat storage capacity. In this study, RT42 paraffin was modified with inorganic nano-oxides (Al2O3, CuO, SiO2, and ZnO) in the presence of sodium dodecyl sulfate (SDS) as a surfactant. The incorporation of SDS improved nanoparticle dispersion and reduced agglomeration, resulting in enhanced phase-change behavior and improved structural homogeneity. Differential scanning calorimetry (DSC) analysis revealed slight variations in melting and crystallization temperatures, while the ZnO-doped composite retained up to 92% of the latent heat storage capacity of pure RT42. Among all the investigated composites, the Al2O3-doped sample exhibited the highest thermal conductivity and specific heat capacity. Thermogravimetric analysis (TGA) indicated an increase of approximately 15–20°C in the decomposition temperature, demonstrating enhanced thermal stability. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses confirmed the preservation of the crystalline structure and improved microstructural uniformity. The developed SDS-assisted nano-oxide/RT42 composites exhibit significant potential for passive thermal regulation in renewable energy and building applications.
AtıfScopus1WoS1OpenAlex1İncele - MakaleYalnız künye2026Scopus SJRQ2Alloy-to-oxide transformation of a spinel-structured (Fe30Cr30Mn20Ni10V10)3O4 high-entropy alloy-oxide via mechanical alloying: Synthesis, phase stability, multivalent surface states, and radiation attenuation behaviour
Güler, Ömer; Güler, Seval Hale; Özkul, İskender; Baykal, Duygu Sen; Tekin, H.O.; ALMisned, Ghada
A spinel-structured high-entropy alloy-oxide (HEAO) with the nominal composition (Fe30Cr30Mn20Ni10V10)3O4 was synthesized via mechanical alloying followed by thermo-mechanical oxidation X-ray diffraction indicated the formation of a predominantly spinel-type cubic oxide phase after oxidation, with the observed reflections being consistent with the Fd-3m spinel structure, while SEM-EDS mapping showed a homogeneous cation distribution at the examined scale. XPS analysis revealed mixed valence states of Fe2+/Fe3+, Cr3+/Cr4+, Mn3+/Mn4+, Ni2+/Ni3+, and V4+/V5+. Thermodynamic parameters supported phase stability, with ΔSmix = 12.51 J K−1·mol−1 and Ω = 2.68. Gamma-ray attenuation properties were evaluated over 0.015-15 MeV. The linear attenuation coefficient decreased from 193.685 cm−1 at 0.015 MeV to 0.309 cm−1 at 1 MeV and stabilized near 0.137 cm−1 at 15 MeV. Correspondingly, the half value layer increased from 0.004 cm to 5.068 cm across the same energy range. The effective atomic number decreased from 24.58 at 0.015 MeV to approximately 15.37 at 1 MeV, followed by a moderate increase to 17.71 at 15 MeV. Comparative analysis with commercial stainless steel, titanium alloys, nickel-based superalloys, ferro-boron systems, and lightweight entropy alloys demonstrated that the synthesized HEAO exhibits intermediate yet stable attenuation performance, positioning it between low-density Al-based systems and high-density Ni-rich alloys. It can be concluded that the alloy-to-oxide strategy enables the production of a structurally stable spinel HEAO with consistent and competitive gamma-ray attenuation behaviour across a broad photon energy spectrum.
AtıfScopus1OpenAlex1İncele - MakaleYalnız künye2026Scopus SJRQ1Flexural response prediction of C-shaped concrete-filled composite plate shear walls (C-PSW/CF) using response surface methodology
Polat, Erkan
Concrete-filled composite plate shear walls (C-PSW/CF) are an emerging prefabricated structural system that combines high strength, stiffness, and constructability for use in high-rise and seismic applications. Conventional plastic-theory-based flexural models originally developed for planar walls are intended only to estimate peak flexural strength; however, they cannot adequately capture several mechanisms governing the behavior of C-shaped sections, including concrete confinement, plate local buckling, von Mises stress interaction, and shear-lag effects. Moreover, no analytical formulations are currently available for predicting the full monotonic flexural response of such walls. This study develops a surrogate-based modeling framework that integrates high-fidelity finite element (FE) simulations with Response Surface Methodology (RSM) to predict the monotonic flexural response and yield moment capacity of C-shaped C-PSW/CF walls. A validated three-dimensional FE model (FEM) was used to simulate 77 wall configurations generated through a Central Composite Design (CCD) by varying six geometric and material parameters. Second-order RSM equations were derived to estimate moment capacity across drift ratios up to ±4% in both loading directions and to predict yield moments corresponding to the onset of web and flange plate yielding. The developed models show high predictive accuracy (R² > 0.95) and successfully capture nonlinear parameter interactions among section geometry, reinforcement ratio, and steel yield strength. Compared with nonlinear FE simulations, the RSM equations enable rapid prediction of wall capacity using explicit closed-form expressions, providing a computationally efficient tool for performance-based design and parametric evaluation of prefabricated composite wall systems.
AtıfScopus1WoS1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ2Eigenfunction Expansion and Parseval Identity of β-Dirac Operators on the Whole Line
Koşar, Nida Palamut; Koşar, Cem; Akcay, Ozge
In the present work, we investigate a (Formula presented.) -Dirac problem on the whole-line. Our primary objectives are threefold: to demonstrate the existence of a spectral function, to deduce the associated Parseval identity, and to formulate an eigenfunction expansion theorem that characterizes the behavior of the problem under consideration.
- MakaleAçık Erişim2026Scopus SJRQ2Experimental and numerical analysis of ceramic fiber geopolymer concrete under blast effect
Dalğıç, Aras; Yılmazer Polat, Berivan; Savaş, Sedat
This study employs both experimental and numerical methods to investigate the blast resistance of ceramic fiber-reinforced geopolymer concrete (CFGC), a cement-free material often referred to as green concrete due to its environmentally friendly nature compared to Portland cement concrete (PCC). Geopolymer concrete specimens, formulated with ground granulated blast furnace slag, silica fume, and varying proportions of ceramic fibers, were subjected to blast tests using 50, 100, 150, 200, and 250 grams of trinitroglycerin (TNG). A standard PCC specimen was utilized as a control. The results demonstrate that the incorporation of 10% ceramic fibers significantly enhances the blast resistance of the geopolymer concrete, reducing crater diameters by up to 20% compared to conventional PCC. Furthermore, the finite element model developed in ANSYS Workbench exhibits a strong correlation with the experimental data, validating the predictive capability of the numerical simulations. Overall, this research highlights the immense potential of CFGC as a sustainable, highly durable alternative for structures exposed to blast loads.
- MakaleAçık Erişim2026Scopus SJRQ1Natural propolis-based coatings as an effective strategy to control microbial growth and quality losses of kiwifruit during cold storage
Ozturk, Burhan; Gun, Sefa; Erturk, Omer; Aglar, Erdal; Yıldız, Kenan; Ozturk, Ahmet
Background: this study investigated the effects of ethanol-extracted propolis applications on the quality characteristics, microbial growth, and microstructural changes of kiwifruit (Actinidia deliciosa) during cold storage. Four different application groups were created: control, 70% ethanol application (ETH), 3% propolis coating (PRO1), and 6% propolis coating (PRO2). After dip coating, the fruits were stored for 150 days at 0 ± 0.5 °C and 90 ± 5% relative humidity, and analyses were performed on days 0, 30, 60, 90, 120 and 150. During storage, weight loss, respiration rate, fruit firmness, color, soluble solids content (SSC), titratable acidity (TA), vitamin C, total phenolics, total flavonoids, antioxidant activity (DPPH and FRAP assays), individual phenolic compounds, and microbial growth were determined in fruit samples. In addition, microstructural changes on the fruit surface were examined using scanning electron microscopy (SEM), and the elemental surface composition was determined using energy dispersive X-ray spectroscopy (EDX). Results: propolis coating applications maintained the quality characteristics of kiwifruit during storage. In particular, PRO1 and PRO2 reduced weight loss and respiration rate, better preserved fruit firmness, and maintained more stable color parameters. Propolis coatings also contributed to the preservation of ascorbic acid, total phenolic compounds, and total flavonoids, ensuring that antioxidant activity remained at higher levels throughout the storage period. Microbiological analyses showed that propolis coatings markedly reduced total bacterial counts on the kiwifruit surface, indicating their potential to limit microbial contamination during cold storage. SEM images showed that propolis coatings formed a homogeneous film layer on the fruit surface and limited microbial colonization by sealing surface pores. EDX analyses showed treatment-dependent changes in the surface elemental composition of kiwifruit peel, whereas SEM observations confirmed the formation of a continuous propolis-derived surface layer. Conclusions: overall, ethanol-extracted propolis coatings reduced total bacterial counts and quality losses in kiwifruit during cold storage and may serve as an effective natural preservative for extending cold-storage life. This journal is
AtıfScopus1OpenAlex1İncele - MakaleAçık Erişim2026Scopus SJRQ2Bernstein-smoothed estimation and bootstrap inference for the lower-tail Spearman's rho curve
Lyu, Guanjie; Ouimet, Frédéric; Susam, Selim O.
This paper studies a Bernstein-smoothed plug-in estimator for the lower-tail Spearman's rho curve, a rank-based measure of local concordance defined through a normalized copula integral over the lower-left square (Formula presented.). The estimator applies the lower-tail Spearman functional to the empirical Bernstein copula and introduces a degree parameter that controls finite-sample regularization. The contribution is target-specific estimation and inference for the lower-tail Spearman's rho curve rather than a new general-purpose copula estimator. We establish uniform strong consistency on compact intervals away from zero whenever (Formula presented.). Under a target-specific integrated Bernstein-bias condition and (Formula presented.), we derive functional weak convergence with the same first-order Gaussian limit as the empirical copula-based estimator; this degree regime includes (Formula presented.). For inference, we justify a smoothed beta bootstrap based on sampling from the empirical beta copula and construct pointwise confidence intervals from the absolute centred bootstrap root. Monte Carlo experiments for the Farlie–Gumbel–Morgenstern, Gaussian, Clayton, and Frank copulas assess pointwise coverage over the threshold grid and show that Bernstein smoothing generally reduces integrated variance and often lowers mean integrated squared error under weak to moderate dependence. Additional common-sample experiments compare the proposed estimator with the empirical beta and empirical checkerboard Bernstein copula estimators in terms of pointwise error, integrated error, computation time, selected degrees, numerical stability, and pointwise coverage. A sensitivity analysis shows that (Formula presented.) is a simple theoretically admissible default that avoids the most severe oversmoothing. A descriptive application to the Loss–ALAE insurance claims data illustrates how the lower-tail Spearman's rho curve can reveal local dependence features that are not captured by the global Spearman correlation.
- MakaleAçık Erişim2026Scopus SJRQ1The Strategic Use of Instructor Visibility in Educational Videos: An Eye-Tracking Data-Based Study
Türel, Yalın Kılıç; Alpsülün, Mustafa; Yuruk, Süleyman Eren; Aslan, Alper; Kokoç, Mehmet; Polat, Hamza; Öztürk Akca, Cemile; Kurşun, Engin
This study developed an exploratory heuristic decision-support framework for dynamically regulating instructor visibility in instructional videos based on learners’ eye-tracking data. Eye-movement data were collected from 40 university students using a Tobii Pro Fusion while viewing 16 explanatory and procedural instructional videos. Instructor and Learning Content Areas of Interest were analyzed using normalized eye-tracking indicators. Descriptive analyses were complemented by Wilcoxon signed-rank tests, binary logistic regression, and receiver operating characteristic (ROC) analyses. Learners allocated significantly greater visual attention to learning content than to the instructor across both video types. Logistic regression identified instructor attention percentage, visit-related metrics, and blink frequency as significant predictors of visibility decisions. ROC analysis showed that instructor attention percentage provided the highest discriminative performance, with an optimal threshold of approximately 30%. Findings suggest that instructor visibility may be particularly appropriate during introductory, summary, and conceptually demanding segments, providing empirically grounded, attention-aware guidance for adaptive instructional video interfaces.
- MakaleYalnız künye2026Scopus SJRQ1Feeding problems in Turkish children with down syndrome and parental quality of life: A cross-sectional study
Okyar, Ferit; Kemer, Duygu
Background Children with Down syndrome (DS) often have feeding problems, which may negatively affect the quality of life (QoL) of their parents. This study aimed to identify feeding problems in children with DS and to examine the relationship between these feeding problems and parental QoL. Methods This cross-sectional study included 105 parents of children aged 10–18 years with DS in Turkey. Data were collected through face-to-face interviews using the Screening Tool of Feeding Problems (STEP) and the SF-36 Health Survey (SF-36). Results This study indicated that the mean STEP scale scores were below the average level across all frequency × severity subscales. Parents' mean scores on the SF-36 QoL scale were above the reference mean (x̄ = 50.00) for the physical functioning, vitality, mental health, social functioning, pain, and general health perception subscales, whereas scores for the physical role limitation and emotional role limitation subscales were below the reference mean. In this study, a moderate negative correlation was found between STEP subscale scores and parents' mean SF-36 subscale scores ( p ≤ 0.05). Conclusions In this study, a significant negative correlation was found between the STEP subscale scores and the parents' mean SF-36 subscale scores. Implications to practice: Routine feeding assessments using the STEP scale should be conducted for children with DS, and nurse-led parent education programs addressing feeding problems should be implemented.
- MakaleYalnız künye2026Scopus SJRQ2Experimental ınvestigation of hybrid passive cooling strategies for photovoltaic modules using nano-enhanced PCM and graphene-coated finned structures under hot climate conditions
Özdemir, Osman; Yücel, Halit Lutfi; Kahraman, Gökhan
This study experimentally investigates the use of several passive cooling techniques to enhance the electrical performance of photovoltaic (PV) modules under high ambient summer temperatures in Elazığ, Turkey. Throughout the trial period of July, August, and September, a system comprising four photovoltaic panels, one designated as a reference, was developed. The first passive cooling arrangement utilized a paraffin-based phase change material (PCM) RT42HC. In the second configuration, a nano-enhanced PCM (NePCM) composite was employed, prepared by dispersing 1 mass% of Al2O3 nanoparticles into the paraffin matrix and stabilizing them with 3 mass% of sodium dodecyl sulfate (SDS) to ensure homogeneous distribution. The third, hybrid configuration integrated 14 graphene-coated parabolic pin-tipped fins mounted externally onto the aluminum enclosure housing the NePCM composite. Experimental results demonstrated that the implemented passive cooling techniques markedly decreased the panel surface temperature, thereby enhancing electrical power output and photovoltaic efficiency. The hybrid graphene-coated fin-NePCM system demonstrated superior performance, achieving a maximum surface temperature reduction of 12.65 °C, a sustained electrical efficiency increase of 6–13%, and an average daily electrical energy gain of 26.23 Wh day−1 compared to the reference module. These findings demonstrate that the integrated hybrid design is an effective and reliable passive cooling method for sustaining photovoltaic system performance under hot climate conditions.
- MakaleYalnız künye2026Scopus SJRQ1High-temperature, freeze–thaw, and sulfate resistance of mortars incorporating ternary blends of fly ash, chromite, and waste glass
Gülmez, Nihan; Kanellopoulos, Antonios
The demand for sustainable construction materials promotes the use of industrial waste in cement-based systems. This study examines mortars incorporating fly ash (FA) (0%, 7.5%, and 15%), waste glass, and chromite aggregates for mechanical and durability performance. Specimens underwent compressive strength, freeze–thaw, high-temperature, sulfate attack, and ultrasonic pulse velocity tests, while microstructure was characterized by x-ray diffraction, thermogravimetric analysis, and scanning electron microscopy–energy-dispersive spectroscopy. Mortars with 7.5% FA exhibited relatively high compressive strength and improved freeze–thaw resistance. The combined use of chromite and FA improved strength retention at 800°C, reaching 23 MPa with 7.5% FA and 50% chromite. The greatest sulfate resistance occurred in mortars containing 15% FA and 15% waste glass, maintaining compressive strengths of 61 and 70.9 MPa after MgSO4 and Na2SO4 exposure, respectively.
- MakaleYalnız künye2026Scopus SJRQ1Evaluation of rainbow trout response to the optimal anesthetic concentration of citronella oil (Cymbopogon nardus) predicted by artificial neural network
Minaz, Mert; Félix, Luís M.; Er, Akif; Köse, Özay; Ak, Kübra; Alparslan, Cem; Serdar, Osman; Aydın, Baki; Kurtul, Irmak; Hoseini, Seyyed Morteza
Anesthesia practices in aquaculture are important for preventing potential stress in fish. For this purpose, interest in natural anesthetic agents as substitute for currently used synthetic anesthetics has increased. In this context, the present study demonstrated the anesthetic efficacy of citronella oil (Cymbopogon nardus) in rainbow trout (Oncorhynchus mykiss) individuals. Based on an artificial neural network (ANN) model derived from preliminary studies, the optimal anesthetic concentration for rainbow trout individuals was estimated as 90 μL L−1. Validation of the concentration predicted by ANN revealed no time-dependent hematological or histological effects on fish to citronella oil. Furthermore, biochemical tests revealed that the partial post-anesthesia increase in ALT and AST values was transient and negligible in light of histological findings. Although oxidative stress was observed during the acute period, the enzymatic activity of SOD and CAT effectively reduced the oxidative damage, demonstrating their role in protecting the fish from oxidative stress. The antioxidant activity observed was temporary, returning to baseline levels without any accompanying tissue damage at the tested concentration. Behavioral monitoring further indicated a swift reduction in motor activity followed by a smooth recovery process, with no evident signs of stress or avoidance behaviour. Overall, these results position citronella oil as a promising natural anesthetic for rainbow trout under the studied parameters. That said, further studies involving various solvents, temperature ranges, and fish species are necessary to comprehensively establish its efficacy and safety.
AtıfScopus4İncele - MakaleAçık Erişim2026Scopus SJRQ1Pomological and Biochemical Characterization of Autochthonous Grape Varieties Grown in Türkiye
Karasu, Yakup; Dogan, Adnan; Aykut, Semih; Ozturk, Burhan; Aglar, Erdal
Grapevine (Vitis vinifera L.) is an important fruit crop with considerable morphological and biochemical diversity, and autochthonous genotypes represent valuable genetic resources for breeding and conservation programs. Many local varieties remain underexplored in terms of pomological and antioxidant traits. Eighteen indigenous grape genotypes collected from Muş province (Eastern Anatolia, Türkiye) were evaluated using morphological and biochemical parameters, including berry traits, phenolic composition, vitamin C, and antioxidant activity. Multivariate analyses including PCA, HCA, and Pearson correlation were performed to classify genotypes and determine trait relationships. The first two PCA components explained 51.9% of the total variation. Antioxidant-related traits mainly contributed to PC1, whereas berry size and anthocyanin content influenced PC2. HCA grouped the genotypes into distinct clusters according to antioxidant capacity and pomological characteristics. Correlation analysis showed significant positive relationships among antioxidant-related parameters. Berry size traits were positively correlated with each other, but negatively associated with seed number and skin thickness. The combined use of pomological, biochemical, and multivariate analyses proved useful for genotype classification. The identification of antioxidant-rich genotypes may support future breeding and conservation studies. The results highlight the importance of indigenous grape germplasm for sustainable viticulture.
- DüzeltmeYayıncıda açık erişim2026Scopus SJRQ1Correction: Comprehensive Biological and Chemical Evaluation of Two Seseli Species (S. gummiferum and S. transcaucasicum) (Antioxidants, (2021), 10, 10, (1510), 10.3390/antiox10101510)
Zengin, Gokhan; Stojković, Dejan; Mahomoodally, Mohamad Fawzi; Jugreet, Bibi Sharmeen; Paksoy, Mehmet Yavuz; Ivanov, Marija; Gašić, Uroš; Gallo, Monica; Montesano, Domenico
In the original publication [1], there was a mistake in Figure 1 as published. The figure, as published, did not include the appropriate statistical information. We have revised the figure accordingly, and the corrected version of “Figure 1” is presented below. The authors state that the scientific conclusions are unaffected. This correction was approved by the Academic Editor. The original publication has also been updated.