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High performance metal-semiconductor-metal visible photodetectors with sulfurization process of CuO and Cu2O thin films
No full textIn this study, thin films of CuO and Cu2O semiconductors were grown on n-type Si (100) and glass substrates by DC magnetron sputtering method in a controlled manner. X-ray Diffraction (XRD) measurements have confirmed that only CuO and Cu2O phases appeared in the respected films. The bandgap values for the CuO and Cu2O thin films are 2.05 and 2.64 eV, respectively, as confirmed by absorption measurements, respectively. When considering photodetector performances, CuO-based thin film has exhibited better responsivity and photosensitivity (Iph/Id) values, with 0.33 A/W and 516 %, respectively. To further improve the photodetector performances, the CuO and Cu2O thin films were sulfurized for 30 min. The sulfurization process has shown that grain boundaries are reduced, and crystal sizes have increased in materials by converting CuO to CuSO4 and Cu2O to Cu2S with minor CuS phases. The bandgaps of the samples have exhibited a reduction, 1.90 eV for CuSO4, and 2.25 eV for Cu2S. Electrical tests on photodetectors have revealed that sulfurized materials have reduced dark current, increased photosensitivity by up to 743 % with larger detectivity for Cu2S sample. Furthermore, improvements in ideality factors and rectification ratios indicate that device performance is significantly improved by sulfurization. In conclusion, the sulfurization process has demonstrated significant improvements in the performance of CuO-based photodetectors by enhancing the responsivity and photosensitivity, making them more efficient for practical applications
BCECNN: an explainable deep ensemble architecture for accurate diagnosis of breast cancer
No full textBackgroundBreast cancer remains one of the leading causes of cancer-related deaths globally, affecting both women and men. This study aims to develop a novel deep learning (DL)-based architecture, the Breast Cancer Ensemble Convolutional Neural Network (BCECNN), to enhance the diagnostic accuracy and interpretability of breast cancer detection systems.MethodsThe BCECNN architecture incorporates two ensemble learning (EL) structures: Triple Ensemble CNN (TECNN) and Quintuple Ensemble CNN (QECNN). These ensemble models integrate the predictions of multiple CNN architectures-AlexNet, VGG16, ResNet-18, EfficientNetB0, and XceptionNet-using a majority voting mechanism. These models were trained using transfer learning (TL) and evaluated on five distinct sub-datasets generated from the Artificial Intelligence Smart Solution Laboratory (AISSLab) dataset, which consists of 266 mammography images labeled and validated by radiologists. To improve transparency and interpretability, Explainable Artificial Intelligence (XAI) techniques, including Gradient-weighted Class Activation Mapping (Grad-CAM) and Local Interpretable Model-Agnostic Explanations (LIME), were applied. Additionally, explainability was assessed through clinical evaluation by an experienced radiologist.ResultsExperimental results demonstrated that the TECNN model-comprising AlexNet, VGG16, and EfficientNetB0-achieved the highest accuracy of 98.75% on the AISSLab-v2 dataset. The integration of XAI methods substantially enhanced the interpretability of the model, enabling clinicians to better understand and validate the model's decision-making process. Clinical evaluation confirmed that the XAI outputs aligned well with expert assessments, underscoring the practical utility of the model in a diagnostic setting.ConclusionThe BCECNN model presents a promising solution for improving both the accuracy and interpretability of breast cancer diagnostic systems. Unlike many previous studies that rely on single architectures or large datasets, BCECNN leverages the strengths of an ensemble of CNN models and performs robustly even with limited data. It integrates advanced XAI techniques-such as Grad-CAM and LIME-to provide visual justifications for model decisions, enhancing clinical interpretability. Moreover, the model was validated using AISSLab dataset, designed to reflect real-world diagnostic challenges. This combination of EL, interpretability, and robust performance on small yet clinically relevant data positions BCECNN as a novel and reliable decision support tool for AI-assisted breast cancer diagnostics
Coating of Ti-6Al-4V sheets with nano-HA-based materials by electrophoretic deposition (EPD) method and investigation of surface properties
Full text linkTitanium alloys, particularly Ti-6Al-4V, are among the most widely used materials in biomedical implant applications due to their superior mechanical strength, corrosion resistance, and compatibility with bone tissue. In this study, Ti-6Al-4V substrates were coated with Hydroxyapatite (HA) and Hydroxyapatite reinforced with 1% Graphene (Gr) using electrophoretic deposition under 40V and 80V. The influence of applied voltage, deposition time, and solution composition on coating morphology, thickness, elemental distribution, and structural properties was systematically evaluated. The most favorable results were obtained at 80V, where homogeneous and adherent coatings were formed. Morphological examinations revealed coating thicknesses ranging from 11.25 mu m to 87.5 mu m. XRD analyses confirmed the presence of Ti alpha, Ti beta, HA, and Gr phases, demonstrating successful composite coating. Surface characterization showed that HA coatings exhibited hydrophilic behavior, while HA-Gr coatings demonstrated super-hydrophilic properties, which are highly advantageous for cellular attachment and osseointegration. Contact angle and roughness measurements further indicated improved biocompatibility of the composite coatings. These findings suggest that HA-Gr coated Ti-6Al-4V alloys possess enhanced surface properties and hold significant potential as advanced biomaterials for implant applications.Afyon Kocatepe University [BAPK 21.MYO.02]; Scientific Research Projects CommissionThis study was supported by Afyon Kocatepe University BAPK 21.MYO.02. Many thanks to the Scientific Research Projects Commission for their support
Detection of Cracks in Cultural Heritage Buildings Using UAV Photogrammetry-Based Digital Twin
No full textNotwithstanding the increasing efforts to conserve and archive historical artifacts, comprehensive documentation employing various technologies remains crucial. Comprehensive documentation will facilitate relaying information about these locations to future generations, ensuring their complete conservation by inspecting their present state. Furthermore, in addition to digital documentation for the conservation of historic buildings, creating an audit that will contribute to future evaluations and interventions is of the utmost importance. As a result, an alternative method is suggested for automatic detection of structural cracks instead of costly on-site inspections. Growing interest has been in developing digital twins (DT) for accurate detection. 3D geometric documentation represents the initial phase in DT development, and diverse instruments and procedures have been designed to support this process. Accurate 3D geometric documentation is achieved by integrating photogrammetry and geodetic methods. The proposed methodology underwent testing on a modern beam structure before being applied to a complex historical structure. The study compared the findings of modern measurement techniques with traditional methods for analyzing automatically detected cracks. The accuracy of modern techniques resulted in a success rate of 78.25%.Afyon Kocatepe University Scientific Research Projects Coordination Unit [23.FEN.BIdot;L.17]This study is part of the PhD thesis of the first author under the supervision of the second author. This study is supported by Afyon Kocatepe University Scientific Research Projects Coordination Unit (Project Number: 23.FEN.B & Idot;L.17)
Life Science Lessons Supported by Virtual Exhibitions: A Mixed-Method Research Study
No full textA virtual exhibition can be defined as an exhibition in which digital content is presented interactively and accessibly over the internet, with content enriched by visuals, texts, videos, and other multimedia tools. Such exhibitions can be created using platforms such as Art Steps, Spatial, or Emaze, with interactive content developed using these applications in the learning and teaching process. In particular, virtual exhibitions can potentially enhance the interactivity and enjoyment of Life Sciences courses. The primary objective of this research is to ascertain the impact of virtual exhibitions on students' attitudes toward the Life Science course and their levels of enjoyment. Additionally, the study seeks to explore students' perceptions of these applications. A mixed-methods research approach was adopted in the study. The study group consists of 15 students from the third grade of a public school. The data collection instruments employed included the Life Science Lesson Attitude Scale, the Life Science Lesson Fun Level Scale, interview forms, and student and researcher diaries. Quantitative data was analyzed using a dependent groups t-test, while qualitative data underwent content analysis. The research findings revealed that the integration of virtual exhibitions in the Life Science course positively impacted students' attitudes towards the course and their levels of enjoyment. The qualitative data analysis indicated that students found the Life Science lessons delivered via virtual exhibitions more interactive an
Sustainable development in Türkiye under the environmental performance index: An assessment in the light of environmental and urban indicators
No full textBu çalışmanın amacı Yale Üniversitesi tarafından yayımlanan Çevresel Performans Endeksi (EPI) kapsamında Türkiye’nin çevresel ve kentsel göstergeler bağlamında sürdürülebilir kalkınma düzeyinin değerlendirilmesidir. Sürdürülebilir kalkınma, ülkelerin sosyal, ekonomik ve çevresel açılardan topyekûn gelişme durumunu kısaca ifade etmektedir. EPI, sürdürülebilir kalkınmanın boyutlarından biri olan çevre üzerinde durmaktadır. Bununla birlikte ilgili endeks alt boyutları bağlamında kentsel göstergeleri de ihtiva etmektedir. Bu bağlamda çalışmada, Çevresel Performans Endeksi (EPI)’nde bulunan ve Birleşmiş Milletler (BM) tarafından belirlenmiş olan sürdürülebilir kalkınma amaçları içerisinde yer alan çevresel ve kentsel boyutlar ve bunlara ilişkin alt boyutlar değerlendirilmektedir. Çalışma doküman analizi yöntemi şeklinde kurgulanmış olup, istatistiki verilerden faydalanılarak yıl bazlı bir karşılaştırma yapılmıştır. Bu bağlamda çalışma kapsamında Türkiye’nin EPI puanının ve dünya ülkeleri içerisindeki sıralamasının negatif yönde seyrettiği saptanmıştır. Bu husus EPI’nın alt boyutları düzeyinde de genel olarak aynı şekildedir. Bu bağlamda sürdürülebilir kalkınmanın çevresel boyutunda ve bu doğrultuda sürdürülebilir kalkınma amaçları içerisinde yer alan iklim eylemi, sudaki yaşam, karasal yaşam, temiz su ve sanitasyon, erişilebilir ve temiz enerji hususlarında sorunlar yaşandığı ifade edilebilecektir. Bu alanlardaki zafiyetin giderilmesi Türkiye’nin sürdürülebilir kalkınma noktasındaki düzeyini daha yukarılara taşıyabilecektir.The aim of this study is to evaluate Türkiye’s sustainable development level in the context of environmental and urban indicators within the scope of the Environmental Performance Index (EPI) published by Yale University. Sustainable development briefly refers to the total development of countries in terms of social, economic and environmental aspects. EPI emphasises the environment as one of the dimensions of sustainable development. However, the relevant index also includes urban indicators in the context of its sub-dimensions. In this context, the study evaluates the environmental and urban dimensions and their sub-dimensions in the Environmental Performance Index (EPI), which are included in the sustainable development goals determined by the UN. The study was designed as a document analysis method and a year-based comparison was made by making use of statistical data. Within the scope of this study, it has been determined that Türkiye’s EPI score and its ranking among the world countries are in the negative direction. This is generally the same at the level of the sub-dimensions of the EPI. In this context, it can be stated that there are problems in the environmental dimension of sustainable development and accordingly in the issues of climate action, aquatic life, terrestrial life, clean water and sanitation, accessible and clean energy, which are included in the sustainable development goals. Elimination of the weaknesses in these areas will be able to raise Türkiye' s level of sustainable development to a higher level
Digital Game Addiction and Peer Interaction: The Role of Parents’ Education Levels
Full text linkThis study investigates the impact of digital game addiction on peer play behaviors and social skills in early childhood, focusing on parents' education levels. Using a sample of 405 participants from Afyonkarahisar, Türkiye, the study employs the Digital Game Addiction Tendency Scale and the Penn Interactive Peer Play Scale (Parent Form). Significant negative correlations were found between the sub-dimensions of disconnection from life and conflict in the Digital Game Addiction Scale and play interaction, indicating that increased digital game addiction tendencies correspond to decreased positive peer play behaviors. No direct correlation was observed between the continuous play and reflection in life dimensions of digital game addiction and peer play interaction. The study emphasizes the importance of balancing digital and peer play experiences for children’s social development. Additionally, it explores how parental education levels influence these dynamics, providing insights and recommendations for families, educators, and policymakers to monitor digital game use and promote balanced play activities. This research adds to the growing literature on digital game addiction and its implications for early childhood development, highlighting the critical role of parental education
The effect of using digital instructional materials on course academic achievement and motivation in the Religious Culture and Moral Knowledge course
Full text linkBu araştırmanın amacı, Din Kültürü ve Ahlak Bilgisi dersinde dijital öğretim materyalleri kullanımının öğrencinin ders başarısına ve ders motivasyonuna etkisinin olup olmadığını, varsa ne düzeyde bir etkisinin olduğunu araştırmaktır. Araştırma karma yöntemle yürütülmüş olup nicel ve nitel verilerin art arda toplandığı açımlayıcı sıralı desen tercih edilmiştir. Çalışma grubu oluşturulurken, araştırmanın yapısına uygun olarak amaçsal örnekleme yöntemi kullanılmıştır. Araştırmanın çalışma grubunu 2023 2024 eğitim öğretim yılında Afyonkarahisar Merkez ilçeye bağlı bir ortaokulun 6. sınıfında öğrenim gören 54 öğrenci oluşturmaktadır. Bu öğrencilerin 27'si deney 27'si ise kontrol grubundadır. Uygulamalar Din Kültürü ve Ahlak Bilgisi dersi 6. sınıf 2. Ünite olan "Namaz" ünitesi üzerinde yapılmıştır. Araştırmanın nicel verileri; araştırmacı tarafından hazırlanan "Namaz Ünitesi Başarı Testi" ve Çelik (2016) tarafından geliştirilen "DKAB Dersi Motivasyon Ölçeği" ile, nitel veriler ise yapılandırılmış gözlem ve deney grubu öğrencileriyle yapılan odak grup görüşmesiyle toplanmıştır. Nicel veriler, veri istatistik programına yüklenerek betimsel analiz, bağımlı ve bağımsız gruplar t-testi, Wilcoxon İşaretli Sıralar (WİS) testi ve etki büyüklüğü testlerinden Cohen d testi uygulanarak analiz edilmiştir. Nitel verilerin analizinde ise içerik analizi yöntemi kullanılmıştır. Araştırma sonucunda; derslerde Web 2.0 araçlarını ve dijital materyalleri kullanmanın akademik başarıya olumlu katkı sağladığı görülmüştür. Aynı şekilde başlangıçta benzer olan motivasyon puanlarının, uygulama sonunda deney grubu lehine farklılaştığı sonucuna ulaşılmıştır. Araştırmanın nitel verileri de nicel verilerini destekler niteliktedir. Görüşme ve gözlem notlarından elde edilen bulgulara göre, öğrencilerin dijital materyallere karşı olumlu bir tutum sergilediklerini, dijital materyalleri ilgi çekici ve faydalı bulduklarını ve bu materyallerin öğrenilenleri pekiştirmeye katkı sağladığını düşündüklerini söylemek mümkündür. Ayrıca dijital materyaller eksik öğrenmelerin tespitinde ve bütün öğrencilerin aktif olarak derse katılmasında da önemli rol oynamaktadır. Bununla beraber dijital materyallerin kullanıldığı derslerde öğrencilerin yanlış cevap verme kaygısı içerisinde olduğu, arkadaşlarının alay edeceğini düşünerek çekindiği ve süre uzadığında öğrencilerin sıkıldığı gözlemlenmiştir. Bu hususlar da dijital materyal kullanımının sınırlılıkları arasında sayılabilir.The aim of this study is to investigate whether the use of digital instructional materials in the Religious Culture and Moral Knowledge course has an effect on students' academic achievement and course motivation and if so, to determine the extent of this effect. The research was conducted using a mixed-method approach, and an explanatory sequential design, in which quantitative and qualitative data were collected consecutively, was preferred. While forming the study group, a purposive sampling method was used in accordance with the structure of the research. The study group of the research consists of 54 sixth-grade students studying at a middle school in the central district of Afyonkarahisar during the 2023–2024 academic year. Of these students, 27 are in the experimental group and 27 are in the control group. The implementation was carried out on the second unit of the 6th grade Religious Culture and Moral Knowledge course, titled "Prayer." The quantitative data of the research were collected using the "Prayer Unit Achievement Test" prepared by the researcher and the "Religious Culture and Moral Knowledge Course Motivation Scale" developed by Çelik (2016), while the qualitative data were obtained through structured observation and a focus group interview conducted with students in the experimental group. The quantitative data were uploaded to a statistical software program and analyzed using descriptive analysis, dependent and independent groups t-tests, and the Wilcoxon Signed-Rank Test (WSRT) and the Cohen d test for the effect size tests. For the analysis of qualitative data, the content analysis method was used. As a result of the research, it was found that the use of Web 2.0 tools and digital materials in lessons positively contributes to academic achievement. Similarly, it was concluded that motivation scores, which were similar at the beginning, differed in favor of the experimental group at the end of the implementation. The qualitative data of the research also support the quantitative data. According to the findings obtained from the interviews and observation notes, it can be said that students exhibit a positive attitude towards digital materials, find digital materials interesting and useful, and believe that these materials contribute to reinforcing what is learned. Additionally, digital materials play an important role in identifying learning gaps and ensuring that all students actively participate in the lesson. However, it was observed that in lessons where digital materials are used, students experience anxiety about giving wrong answers, hesitate due to fear of being mocked by their peers, and become bored when the duration is prolonged. These issues can be considered among the limitations of using digital materials
Two-Stage EDAS Decision Approach with Probabilistic Hesitant Fuzzy Information
No full textThis paper develops a two-stage decision approach with probabilistic hesitant fuzzy data. Research challenges in earlier models are: (i) the calculation of occurrence probability; (ii) imputation of missing elements; (iii) consideration of attitude and hesitation of experts during weight calculation; (iv) capturing of interdependencies among experts during aggregation; and (v) ranking of alternatives with resemblance to human cognition. Driven by these challenges, a new group decision-making model is proposed with integrate methods for data curation and decision-making. The usefulness and superiority of the model is realized via an illustrative example of a logistic service provider selection
Trust, Professionalism and Empowerment: How School Leaders Shape Instructional Practices
Full text linkThis study investigates the impact of school leadership on changed instructional practices through the mediating roles of trust in administrators, teacher professionalism and psychological empowerment. Data were collected from 925 teachers in T & uuml;rkiye and analysed using structural equation modelling. Results indicate that school leadership significantly enhances changed instructional practices, with effects mediated through trust in administrators, teacher professionalism and psychological empowerment. Additionally, school leadership positively influences teacher professionalism, mediated by trust in administrators and psychological empowerment. These findings underscore the influence of school leadership within a non-Western, centralised education context on instructional practices and professional development among educators. The study highlights the critical role of school leaders in promoting changes in teaching methodologies and cultivating a supportive professional environment. Implications for policy, practice and future research directions are discussed