Scopus İndeksli Yayınlar Koleksiyonu

Bu koleksiyon için kalıcı URI

Güncel Gönderiler

Listeleniyor 1 - 20 / 2952
  • Öğe
    Use of fractional calculus to avoid divergence in Newton-like solver for solving one-dimensional nonlinear polynomial-based models
    (Elsevier BV, 2025-04) Sania Qureshi; Amanullah Soomro; Ioannis K. Argyros; Krzysztof Gdawiec; Ali Akgül; Marwan Alquran
    There are many different fields of study where nonlinear polynomial-based models arise and need to be solved, making the study of root-finding iterative solvers an important topic of research. Our goal was to use the two most significant fractional differential operators, Caputo and Riemann–Liouville, and an existing time-efficient three-step Newton-like iterative solver to address the growing interest in fractional calculus. The classical solver is preserved alongside a damping term created within it that tends to 1 as the fractional order α approaches 1. The solvers’ local and semi-local convergence are investigated, and the stability trade-off with convergence speed is discussed at length. The suggested fractional-order solvers are tested on a number of nonlinear one-dimensional polynomial-based problems that come up in image processing, mechanical design, and civil engineering, such as beam deflection; and many more.
  • Öğe
    Second order slip micropolar MHD hybrid nanofluid flow over a stretching surface with uniform heat source and activation energy: Numerical computational approach
    (Elsevier BV, 2025-03) Syed Arshad Abas; Hakeem Ullah; Mehreen Fiza; Ali Akgul; Aasim Ullah Jan; Magda Abd El-Rahman; Seham M. Al-Mekhlafi
    Applications: Micropolar fluids are extensively used in lubrication, polymer processing, and heat transfer applications to enhance performance in systems with suspended microstructures. These fluids find applications in industries such as medical, chemical, and microfluidics. Recent advancements have highlighted the potential of hybrid nanofluids in further improving thermal and flow characteristics. Novelty: Motivated by these developments, this study investigates the heat and mass transfer characteristics of a micropolar hybrid nanofluid comprising titanium dioxide (TiO2) and silver (Ag) nanoparticles suspended in water. The analysis focuses on the effects of slip boundary conditions, Joule heating, thermal radiation, heat sources, magnetohydrodynamic (MHD) effects, activation energy, and binary chemical reactions. Methodology: A mathematical model is formulated based on boundary-layer approximations, leading to a system of partial differential equations (PDEs) that describe the flow, thermal, and concentration fields. These PDEs are subsequently transformed into a set of ordinary differential equations (ODEs) using similarity transformations. The resulting higher-order nonlinear ODEs are solved numerically using the bvp4c technique in MATLAB. Findings: The results reveal that the inclusion of slip boundary conditions significantly influences the flow dynamics, reducing skin friction by 4.9 % and 10.4 % with increasing magnetic and material parameters, respectively, but enhancing it with a higher slip factor by 18.88 %. Additionally, an increased volume fraction of nanoparticles elevates the heat transfer rate by 6.3 % while diminishing the Sherwood number by 2.6 %, showcasing the thermal enhancement capabilities of the hybrid nanofluid. This study contributes to the field by providing new insights into the combined effects of Joule heating, activation energy, and chemical reactions on micropolar hybrid nanofluid flow. The result of bvp4c compared with previous literature and found to be closely aligned with published work. The findings have implications for the optimization of thermal management systems and processes in advanced engineering and industrial applications.
  • Öğe
    Nonlinear normalized fractional electroosmotic spacelike fluid model
    (Elsevier BV, 2025-03) Talat Körpinar; Zeliha Körpinar; Ali Akgül; Qasem Al-Mdallal
    In this paper, we present optical recursively fractional SKμ−electroosmotic fractional recursivelySKμ−energy. Also, we have spacelike microfluidicsfractional SKμ− electroosmotic recursively tension energy. Moreover, we construct main Katugampola recursive-normal hyperbolic fractional KFα−tension field in hyperbolic space. Finally, we characterize spacelike radiative recursively fractional SKμ− phase in hyperbolic space.
  • Öğe
    Thermal radiation effects of ternary hybrid nanofluid flow in the activation energy: Numerical computational approach
    (Elsevier BV, 2025-03) Hakeem Ullah; Syed Arshad Abas; Mehreen Fiza; Aasim Ullah Jan; Ali Akgul; Magda Abd El-Rahman; Seham M. Al-Mekhlafi
    Significance: The remarkable thermal conductivity and heat transfer characteristics of nanofluids make them extremely valuable in thermal engineering and other areas. Due to their increased effectiveness, nanofluids are incredibly useful for improving the efficiency of cooling systems, heating processes, and thermal management applications. Rotating machinery and gas turbine rotators are some industrial applications of hybrid nanofluids as heat transport fluids. Purpose: This study introduces a novel investigation into heat transport phenomena of ternary hybrid, hybrid and nanofluid containing copper, silver and alumina nanoparticles within two stretchy rotating disks maintaining a constant distance. The analysis incorporates the effects of thermal radiation, heat source, joule heating, and Arrhenius activation energy into the equations to stabilize the new composition's flow and thermal properties. Methodology: After utilizing von Karman similarity transformations to renovate the principal equations into the set of nonlinear differential equation systems, the resulting equations were solved using the bvp4c numerical approach with the assistance of MATLAB software. Findings: Graphs are used to explain the results in three different kinds of flows: hybrid fluid (Cu+Al2O3/H2O), nanofluid (Cu/H2O), and ternary hybrid fluid (Cu+Al2O3+Ag/H2O). Additionally, the outcomes of the variable parameters are presented and briefly discussed for different flow profiles. There is encouraging evidence that the numerical code for this study is compatible with previously published work. The skin friction improves 5 % due to the higher values of magnetic and stretching parameter at lower disk. The rate of the heat transfer improved 28 % for ternary nanoparticles as compared to hybrid and single nanofluids. Sherwood's number exhibits both growing and decreasing behaviors for Schmidt and Reynolds’ numbers. All the involved factors enhances the temperature profile. The radiation parameter boost the Nusselt number for ternary hybrid nanofluid up to 6 % and 3.4 % at lower and upper disk as compare to nanofluid.
  • Öğe
    Advanced Soft Computing Techniques for Monthly Streamflow Prediction in Seasonal Rivers
    (MDPI AG, 2025-01-19) Mohammed Achite; Okan Mert Katipoğlu; Veysi Kartal; Metin Sarıgöl; Muhammad Jehanzaib; Enes Gül
    The rising incidence of droughts in specific global regions in recent years, primarily attributed to global warming, has markedly increased the demand for reliable and accurate streamflow estimation. Streamflow estimation is essential for the effective management and utilization of water resources, as well as for the design of hydraulic infrastructure. Furthermore, research on streamflow estimation has gained heightened importance because water is essential not only for the survival of all living organisms but also for determining the quality of life on Earth. In this study, advanced soft computing techniques, including long short-term memory (LSTM), convolutional neural network–recurrent neural network (CNN-RNN), and group method of data handling (GMDH) algorithms, were employed to forecast monthly streamflow time series at two different stations in the Wadi Mina basin. The performance of each technique was evaluated using statistical criteria such as mean square error (MSE), mean bias error (MBE), mean absolute error (MAE), and the correlation coefficient (R). The results of this study demonstrated that the GMDH algorithm produced the most accurate forecasts at the Sidi AEK Djillali station, with metrics of MSE: 0.132, MAE: 0.185, MBE: −0.008, and R: 0.636. Similarly, the CNN-RNN algorithm achieved the best performance at the Kef Mehboula station, with metrics of MSE: 0.298, MAE: 0.335, MBE: −0.018, and R: 0.597.
  • Öğe
    New Approaches in Viticulture: Different Rates of Net Shadow Applications to Yield, Must, Color and Wine Quality
    (MDPI AG, 2025-01-01) Tuba Uzun Bayraktar
    This study was conducted on the Sinceri grape variety in 2023. Three applications (35%, 55% and 75% net shadows) and a control were applied in the experiment. The shading materials were covered over the vines when the grapes were at veraison. The effects of the applied net shadows on the grape yield, color parameters of the berry skin and physicochemical analyses in the must were examined. In addition, some chemical analyses [such as pH, ethyl alcohol (%), volatile acidity (mg/L), reducing sugar (g/L), density and total acidity (g/L)], secondary metabolites, color parameters and sensory analyses were performed in wines produced spontaneously by the microvinification method. In terms of the yield parameters, the 55% net shadow application provided a 61.93% increase in grape yield, 37.83% increase in cluster weight and 35.76% increase in 100-berries weight compared to the control. While the L* value and Hue angle increased, the a* value, b* value and Chroma value decreased as the proportion of shading material increased. In the must, the must yield and total acidity increased while the TSSC, maturity index and density decreased. In terms of the physicochemical wine analysis (ethyl alcohol, density, total phenolic compound and antioxidant amount) and sensory evaluations, the best result was given by 75% net shadow and, in terms of wine color parameters, by 55% net shadow application.
  • Öğe
    Biochar in conjunction with reduced doses of mineral fertilizers increased yield attributes and yield of rice (cv. BRRI dhan29)
    (Pakistan Journal of Botany, 2024-08-30) Md. Rayhanul Hoque; S.M Rahman; S.A. Ruba; J. Ferdous; Kamrunahar K.V.; Md. Rafiqul Islam; Zeki Erden; Muhammad Aamir Iqbal; Walid Soufan; Samer Abo Dawaba; Mohammad Sohidul Islam
    Recently, biochar (BC) applied in optimized quantities has emerged as an effective organic amendment for improving the physico-chemical features of the soil along with boosting the yield attributes of cereals. In the research field of Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur a field experiment was directed to assess the impact of BC implication united with reduced doses of recommended chemical fertilizers (RDF including N, P, K and S) on the growth and yield of rice (cv. BRRI dhan29). It was comprised of five treatments viz. T1= Recommended doses of RDF, T2 = BC 10 t ha-1, T3 = BC 10 t ha-1 + half RDF, T4= Biochar 7.5 t ha-1 + half RDF and T5 = BC 5 t ha-1 + half RDF. The experimental design was the regular arrangement of Randomized Complete Block Design (RCBD) along with four replications. The T1 treatment recorded the maximum plant height (103.00 cm) and the number of tillers hill-1 (26.10) which remained statistically identical to T3. Likewise, T3 out performed rest of regimes by recording the highest values of panicle length (24.89 cm), grains number panicle-1 (195.40), filled grains number panicles-1 (191.10), and 1000-grain weight (25.53 g). Moreover, the same treatment recorded for grain yield (7.82 tha-1) and straw yield (8.76 t ha-1) which was statistically at par to T1 (7.46 and 8.72 t ha-1, respectively). Furthermore, T3 also remained superior as for as biological yield (16.58 t ha-1) of rice was concerned. The outcomes of this trial reveal that BC (10 t ha-1) application have potential to reduce CF dose up to 50% for improving the yield attributes and grain output of rice. (cv. BRRI dhan29).
  • Öğe
    Wheat genotypes respond differently under polyethylene glycol (PEG) induced drought stress during germination and early seedling growth stages
    (Pakistan Journal of Botany, 2024-08-01) Mst Masuma Akhter; M.A. Hasan; M.M. Bahadur; M.R. Islam; Muhammad Aamir Iqbal; Walid Soufan; Khandakar Aurib; Tanjila Akhter; Sipan Soysal; Ayman Elsabagh; Elsabagh Heniesh; Mohammad Sohidul Islam
    Water scarcity has emerged as one of a critical environmental constriction that negatively affect wheat growth, development and yield in Bangladesh. Identification of drought tolerant genotypes is crucial at drought sensitive initial stages of plant growth especially germination and seedling growth stages. To cater this issue, 30 wheat genotypes were subjected to polyehelene glycol (PEG 6000) induced drought stress levels of 0,-2.0 and-4.0 Mpa (osmotic stresses) and their response was tested at the germination and seedling growth stages. The experimental set up was Completely Ramdomized Design (CRD) with five replications. The results revealed that the rate of germination (RG) among the genotypes varied significantly with the different water potential levels, and the RG decreased with the advancement of stress. The stress tolerance index (STI) values based on RG were > 0.900 in wheat cultivars of Shatabdi, BARI Gom 25, BAW 1118, BAW 1151, BAW 1161, E 2, E 18, E 30, E 34 and E 38under severe water deficit stress, while the values were < 0.800 in wheat genotypes BARI Gom 26, BARI Gom 27, BARI Gom 28, BAW 1130, BAW 1140, BAW 1143, BAW 1168, E 28 and E 42. The co-efficient of germination (COG) was significantly decreased with increasing water potential stresses (-2 &-4 bars), and the genotypes Sourav, BARI Gom 25, BAW 1118, BAW 1135, BAW 1151, BAW 1157, BAW 1161, BAW 1163, BAW 1170, BAW 1171, E 2, E 18, E 23, E 29, E 34 and E 38showed > 0.980 STI values whereas, BARI Gom 26, BARI Gom 27, E 24, E 28, E 42, BAW 1130, BAW 1140 and BAW 1168 produced < 0.970 STI values under higher water potential. Higher STI values (> 0.920) regarding the germination vigour index (GVI) under higher water stress were observed in BARI Gom 25, E 18, E 23, E 34, E 38, BAW 1118, BAW 1161 and BAW 1170, and very lower STI values (< 0.800) were obtained in the Shatabdi, BARI Gom 26, BARI Gom 27, BAW 1130, BAW 1140, BAW 1168, E 3, E 24, E 28 and E 42 genotypes. The genotypes Shatabdi, BARI Gom 25, E 18, E 38, BAW 1118, BARI Gom 27, E 24, E 34, BAW 1143 and BAW 1170 showed higher STI values (> 0.550) indicating tolerant genotypes and the genotypes Sourav, BARI Gom 26, BARI Gom 28, BAW 1130, BAW 1151, BAW 1168, E 2, E 3, E 28 and E 29demonstrated lower STI values (< 0.450) designating susceptible genotypes. As water deficit stress increased, the shoot weight (g) of wheat genotypes decreased. Notably, genotypes Shatabdi, BARI Gom 25, E 18, E 34, E 38, and BAW 1118 exhibited Stress Tolerance Index (STI) values greater than 0.700. In contrast, genotypes BARI Gom 26, E 2, E 23, E 29, BAW 1130, BAW 1140, BAW 1151, BAW 1157, and BAW 1161 displayed STI values lower than 0.550. The genotypes showing higher and lower STI values denoted water stress tolerant and susceptible genotypes, respectively.
  • Öğe
    Associations between leptin gene polymorphism and some reproductive traits in Holstein-Friesian dairy cattle
    (Journal of the Hellenic Veterinary Medical Society, 2024) Mustafa Kibar; Aytekin İ.
    The aim of this study was to determine the effect of leptin gene polymorphism and other environmental factors on age at first breeding (AFB; day), age at first calving (AFC; day), service period (SP; day), number of inseminations per conception (NIPC; count), gestation period (GP; day) and calving interval (CI; day). For this purpose, whole blood samples were obtained from the Vena coccygea of 212 Holstein-Friesian dairy cattle reared on a private farm in Türkiye. The Sau3AI restriction enzyme with the PCR-RFLP method was used to determine the polymorphism of 422 base pairs (bp) in the intron 2 region of the leptin gene. The frequencies of the A and B alleles and the AA, AB and BB genotypes were determined to be 0.8821 and 0.1179, and 0.764, 0.236 and 0.000, respectively. There were no animals with the BB genotype in the population. The population of Holstein-Friesian was also at the level of Hardy-Weinberg equilibrium with regard to the leptin gene (P>0.05). The study found the highest direct heritability in the GP trait (0.33±0.268), while the lowest was observed in the NIPC trait (0.01±0.118). For the traits SP (P<0.10), NIPC (P<0.05), and CI (P<0.05), higher values were recorded in cattle with genotype AA compared to those with genotype AB. However, no significant association was found between genotypes and AFB, AFC, GP, and estimated breeding values (EBVs). This suggests that the heritability of these traits may not be strongly affected by the genotypes emphasized. As a result, the AB genotype or B allele could be used in selection for SP, NIPC, and CI, but the allele or genotype did not suggest marker-assisted selection (MAS) for AFB, AFC, and GP. Copyright
  • Öğe
    The Effect Lead Stress on the Early-Stage Development of Solanum melongena L. Seedling
    (Springer Nature Switzerland, 2024) M. Zeki Karipçin; Fatih Çiğ; Laman Majidova; Munavvar Safarova
    The effects of plant growth promoting bacteria (PGPB) application on shoot and root lengths, root thickness and root lateral numbers of aubergine (Solanum melongena) seedlings in a lead stress environment were investigated. Also a control group was formed in addition to lead and bacteria conditions. In this study Stenotrophomonas maltophilia (TV14B) was used. Pb [Pb(NO3)2] (control, 50 and 100 ppm) was used for created abiotic stress for this experiment. Random bloks were designed for this research with 3 repetitions. 10 Solanum melongena seeds were used in each replication. While no value was obtained in root lateral measurements, no difference was detected at the level of statistical significance between shoot length values. Statistically significant differences were detected between root length values at the 1% significance level and between root thickness values at the 5% significance level. It was noted that root thickness increased under lead stress conditions, root lengths increased with the first dose of lead application, giving the expected results under stress conditions, but elongation increased less than the control group plants with the second dose of lead application.
  • Öğe
    The Use of Seaweed Fertilizer in Cereal Cultivation
    (Springer Nature Switzerland, 2024) Fatih Çığ; Rojin Özek; M. Zeki Karipçin; Gunel Mammadova; Tarana Gılıcova
    Factors such as environmental pollution, decrease in water resources, excessive use of fertilizers and pesticides negatively affect soil fertility and cause a decrease in the amount of organic matter in the soil. Plants that do not get enough nutrients from the soil are provided with organic fertilizers. Seaweed manure is one of the most commonly used organic fertilizers for this purpose. Studies have shown that seaweed fertilizer facilitates the biodegradation process and increases seedling growth and photosynthetic pigment components. It has been shown to improve productivity, phenolic content (PC), indole acetic acid (IAA) and total soluble sugar (TSS) content under drought conditions. It has also been found to increase germination, plant growth and antioxidant enzyme activity in case of salinity stress. It has been proven by various studies that seaweed fertilizer also increases the leaf ratio and grain protein ratio. In addition to the application of seaweed fertilizer to the soil and leaves, it is also common to use it as a seed coating. With all its features, algae fertilizer provides less chemical fertilizer use. This review was made to examine the importance of using algae fertilizer to meet the nutritional needs of grains and in various stress situations.
  • Öğe
    Comprehensive Evaluation of Changes in Placentomes in the Second and Third Trimesters of Pregnancy in Cross‐Bred Hamdani Sheep
    (Wiley, 2025-01) Banu Kandil; Ali Osman Turgut; Davut Koca; Fatma Isbilir; Muhammed Zahid Atli; Barıs Can Guzel
    Background: A proper placentation is required for establishment and continuity of pregnancy. In sheep, placentomes are unique structures that enable nutrition and gas exchange between the mother and the foetus. Although placentomes are dynamic formations, there is limited knowledge of changes in placentomes during pregnancy. Objective: This study aimed to identify changes in sheep placentomes in the second and third trimesters of pregnancy using both macroscopic and microscopic methods. Methods: This study investigated 14 healthy cross-breed Hamdani sheep placentomes, comprising seven second and seven third trimesters of pregnancy. The histomorphometric analysis included measurements of capillary number and area in cotyledonary and caruncular regions, while morphometric assessments encompassed placentome dimensions such as number, length, width, and depth. Results: Placentomes were oval and circular in shape in the second and third trimesters. In the second trimester, they were observed as concave structures with thick edges, whereas in the third trimester, they were determined as thin-edged structures with a slight depression in the centre. In the third trimester, foetal and maternal tissues became more intertwined with increased branching of foetal villi and maternal crypts. Placental hematomas and erythrocytes in the cytoplasm of trophoblast cells were more prominent in the third trimester. Statistical analysis revealed no difference in placentome number between the second and third trimesters. However, the dimensions (length, width, and depth) of placentomes were greater in the third trimester compared to the second trimester (p < 0.001). Additionally, while there was no difference in the number of cotyledonary versus caruncular capillaries in the second trimester, cotyledonary capillaries outnumbered caruncular capillaries in the third trimester (p < 0.001). Furthermore, both cotyledonary and caruncular capillary areas increased in the third trimester compared to the second trimester, with the caruncular capillary area being consistently higher than the cotyledonary capillary area in both trimesters (p < 0.05). Conclusion: This study underscores the substantial structural and physiological transformations of placentomes in the second and third trimesters of pregnancy in sheep. These adaptations facilitate efficient flow exchange between the foetus and mother, highlighting the dynamic nature of placental development during late gestation.
  • Öğe
    Are the Notions of Leader–Member Exchange and Organisational Citizenship Effective in Enhancing Teachers’ Job Performance in Türkiye? A Moderated Mediation Model
    (MDPI AG, 2025-01-02) Mehmet Sabir Çevik
    This study is correlational and cross-sectional quantitative research that examines the moderating role of working time with the school principal on the effect of leader-member exchange on teachers' job performance through organisational citizenship. Data were collected from 481 teachers in 43 public schools across the western, central, northern, southern, and eastern regions of Türkiye using the convenience sampling method. The Leader-Member Exchange Scale, Organisational Citizenship Scale, and Employee Performance Scale were used as data collection tools. Data were analysed through descriptive analyses, Pearson correlation analysis, and moderator and moderated mediation analyses. The results indicated positive and significant relationships among leader-member exchange, organisational citizenship behaviours, and teachers' job performance. It was found that leader-member exchange indirectly affected teachers' job performance through organisational citizenship, and working time with the school principal served as a moderator in the relationship between leader-member exchange and organisational citizenship. The indirect effect of leader-member exchange on job performance through organisational citizenship was stronger for teachers with shorter working durations with the principal.
  • Öğe
    Effects of topical neutral protamine Hagedorn insulin on corneal wound healing: an experimental study in rabbits
    (Informa UK Limited, 2025-01-22) Başak Kurt; İsa Özaydin; Lokman Balyen; Sevil Atalay Vural; Uğur Aydin; Özgür Özöner
    Corneal injuries are common in human and veterinary ophthalmology. There are many studies which have investigated the treatment of corneal epithelial defects. This study aimed to investigate the effects of Neutral Protamine Hagedorn (NPH) insulin as an ointment for wound healing in experimental corneal defects. First, a superficial keratectomy was performed on 12 rabbits using a corneal trephine. The animals were divided into two groups, Group I (treated, n = 6) and Group II (vehicle control, n = 6). Insulin ointment was applied topically once daily in the treated group, and saline ointment was applied in the same manner in the vehicle control group. Corneal defects were observed and photographed, and changes in wound surface were recorded on days 7, 14, 21, 30, and 60. In both groups, a significant reduction in the wound surface area was noticeable on the 30th day after defect creation. Between the 30th and 60th days, while the changes in the wound surface area in Group II remained limited, the decrease continued rapidly in Group I. At the end of the study, the corneal opacity score observed was lower in Group I than in Group II. In conclusion, we determined that topical NPH insulin may accelerate corneal wound healing after superficial lamellar keratectomy. A new alternative treatment may be developed for treating corneal wounds through continuing studies on this subject.
  • Öğe
    Comparative analysis of hall current impact on MHD laminar surface tension gradient 3D flow of propylene glycol based tetra hybrid nanofluid with generalized fick's and fourier's perspective
    (Elsevier BV, 2025-03) Munawar Abbas; Shirin Shomurotova; Qasem Al-Mdallal; Ali Akgül; Zuhair Jastaneyah; Hakim AL Garalleh
    Examine the significance of the Cattaneo-Christov flux model on the Marangoni convection 3D flow of tetra hybrid nanofluid combined with Hall current in the present study. When exposed to a fluctuating magnetic flux, it demonstrates electrical conductivity over a stretchy sheet. Using the Cattaneo-Christov double diffusion (CCDD) model, the problem is simulated. In this work, the CCDD model is used to analyze the mass and heat transmission tetra hybrid nanofluid. Basic Fourier's and Fick's laws are generalized by their application. A tetra hybrid nanofluid consisting of Molybdenum disulfide (Mos2), copper (Cu), Silicon dioxide (SiO2) and cobalt ferrite (CoFe2o4), propylene glycol (C3H8O2) as the base fluid is used. This model is essential for precisely predicting the behaviors of heat transfer in nanofluid flows since it takes thermal relaxation time into consideration. Its uses include optimizing heat exchanger performance, enhancing cooling systems in electronics, and better thermal management in microfluidic devices. The basic set of equations is resolved employing the numerical technique (bvp4c). The nanofluid, hybrid, trihybrid, and tetra hybrid nanofluid graphs are all compared. The stretching ratio parameter indicates rising trends in the flow distributions, although the opposite performance is observed for thermal and concentration distributions. Rate of heat and mass transmission improve of tetra hybrid, trihybrid, hybrid nanofluids as increase the values of Marangoni convection.
  • Öğe
    Bullying Among Special Education Students
    (SAGE Publications, 2025-01-21) Halil Aslan; Özgür Erdur-Baker
    The purpose of the study is to examine traditional and cyberbullying among the students with special education needs attending special education schools. Additionally, traditional and cyber victimization among special education students have been examined in terms of gender and grade levels. A sample of the present study consists of 295 students with special education needs (177 gifted, 118 deaf) attending segregated special education schools. The Revised Olweus Bully/Victim Questionnaire, the Revised Cyber Bullying Inventory-II, the Strengths and Difficulties Questionnaire, and a demographic data sheet were employed to collect data. Results of the study indicated that of the total 295 students with special education needs, 28.1% of the students with special education needs were bullies and 39.3% were victims of traditional bullying. Furthermore, 13.5% of the students with special education needs were identified as cyberbullies, and 23.3% of them were found as cybervictims. When gender and grade level were examined in regard to traditional and cyber victimization, significant gender differences were found in 9 and 10 grade levels. Male students with special education needs obtained higher scores for victimization than female students with special education needs. The results of the study were discussed in the light of literature.
  • Öğe
    A novel regional forecastable multiscalar standardized drought index (RFMSDI) for regional drought monitoring and assessment
    (Elsevier BV, 2025-03) Aamina Batool; Veysi Kartal; Zulfiqar Ali; Miklas Scholz; Farman Ali
    Drought is a complex recurrent natural phenomenon. It is the main outcome of climate change. It has long-term impacts on agriculture, human life as well as the environment. Therefore, quantifying drought at the regional level is essential for developing sustainable policies. This study introduced a new drought index for regional drought forecasting called the Regional Forecastable Multiscalar Standardized Drought Index (RFMSDI). The RFMSDI methodology is based on Forecastable Component Analysis (FCA) and K-Component Gaussian Mixture Distribution (K-CGMD). FCA reduce dimension by focus on components that are inherently more predictable. It ensures that reduced data has a built-in ability to predict future trends by selecting the maximized forecastable components. K-CGMD is utilized to model the multimodel time series data. The study application incorporates eight meteorological stations in Türkiye's Elazig province (Baskil, Agin, Elazig, Karakocan, Keban Maden, Palu and Sivrice). The effectiveness of RFMSDI is evaluated by analyzing precipitation data over these meteorological stations of Türkiye. The comparative assessment of the research signifies the superiority of FCA for regional data aggregation. In this research, the comparative assessment of RFMSDI is evaluated against the Standardized Precipitation Index (SPI) by analyzing Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) metrics across different time scales using various machine learning and traditional time series models. The research findings include the following: 1) K-CGMD is a better fitting approach for standardizing RFMSDI and SPI based on reduced BIC values. 2) RFMSDI has superior performance over SPI based on the lower values of RMSE and MAE. 3) Both machine learning and classical methods reveal that RFMSDI outperforms SPI in predicting droughts. 4) SPI shows localized advantages with the ELM training set at 1- and 6-month time scales but RFMSDI offers a more comprehensive and consistent tool for drought prediction, especially when tested on unseen data. In general, the findings endorse the effectiveness of RFMSDI for monitoring drought on a regional level.
  • Öğe
    JazariInteractiveFloor: A modular Java framework for real-time interactive floor applications
    (Elsevier BV, 2025-02) Musa Ataş; İsa Ataş
    JazariInteractiveFloor presents a modular Java framework built upon Processing library for developing real-time interactive floor applications. The framework implements a component-based architecture consisting of an InputManager for computer vision tasks, BlobDetector for motion tracking, and AnimationManager for interactive visualizations. Using an event-driven design pattern through custom listener interfaces, the framework enables seamless integration between motion detection and animation subsystems. The system's modular architecture allows developers to extend functionality through custom animations while maintaining real-time performance. Our implementation has been rigorously tested in a controlled laboratory environment, demonstrating its practical applicability for various potential applications.
  • Öğe
    Effective and environmentally friendly Co nanocatalyst on sodium borohydride hydrolysis in different solvents
    (Elsevier BV, 2025-01) Erhan Onat; Selma Ekinci; Ömer Şahin; Mehmet Sait İzgi
    This study investigates the development and performance of a cobalt (Co) nanocatalyst supported by carbon quantum dots (CQDs) for hydrogen production via sodium borohydride (NaBH₄) hydrolysis. The CQDs were synthesized using a hydrothermal method from caffeine and subsequently used to support the cobalt catalyst. The structure and properties of the synthesized catalyst were characterized using techniques such as X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and energy dispersive spectroscopy (EDX). The catalytic performance was evaluated in various solvents, with the highest hydrogen production rate observed in ethanol. The optimal conditions for Co@CQDs catalyst synthesis were identified as an 8-h hydrothermal treatment with a 3 mmol metal loading. The catalyst demonstrated excellent reusability, maintaining 100% hydrogen production efficiency after seven cycles. The activation energy for the hydrolysis reaction was found to be lower for catalysts synthesized in ethanol (25.48 kJ mol−1) compared to those synthesized in water (35.57 kJ mol−1), indicating enhanced catalytic activity. Under optimum conditions, the hydrolysis reaction in the presence of Co@CQDs (water) catalyst produced 23753 mL min−1 g−1 of hydrogen, while the hydrolysis reaction in the presence of Co@CQDs (ethanol) catalyst produced 28751 mL min−1 g−1. This study highlights the potential of CQDs-supported Co nanocatalysts for efficient and sustainable hydrogen production.
  • Öğe
    Green-synthesized ZrFeO nanoparticles as efficient cathode materials in PEM fuel cells
    (Elsevier BV, 2025-01) Suna Tarhan; Arzu Ekinci; Orhan Baytar; Abdurrahman Akdag; Ömer Şahin
    This study explores the application of ZrFeO nanoparticles, synthesized from fig leaf extract through a green synthesis method, as cathode materials for PEM fuel cells. The nanoparticles, doped with FeO and varying Zr ratios, were combined with Pt metal and characterized using XRD, SEM, EDX, and TEM to analyze their structural and morphological properties. The particle sizes for FeO and Zr-doped FeO were determined to be 2 nm and 2.5 nm, respectively. The electrochemical active surface areas of the catalysts—Pt-FeO/C and Zr-doped variants (PtFeO/C-1 wt%Zr, PtFeO/C-5 wt%Zr, and PtFeO/C-10 wt%Zr)—were measured as 97, 154, 138, and 119 m2/gPt, respectively, demonstrating a significant enhancement in surface area with the incorporation of Zr at optimal doping levels. Catalyst retention after 250 cycles was 29% for Pt–FeO/C, 60% for 1 wt% Zr-doped Pt–ZrFeO/C, 93% for 5 wt% Zr-doped Pt–ZrFeO, and 71% for 10 wt% Zr-doped Pt–ZrFeO. Performance testing at 70 °C revealed a hierarchy of catalytic activity: Pt–ZrFeO/C > Pt–FeO/C > Pt/C. The findings highlight the potential of green-synthesized ZrFeO nanoparticles as effective support materials for cathode catalysts, offering improved performance in PEM fuel cells while markedly reducing platinum dependency. This innovative approach integrates environmental sustainability with technological progress in fuel cell applications.